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Chronic human immunodeficiency virus (HIV) infection not only causes a gradual loss of CD4+ T cells but also leads to a disturbance of the T cell receptor (TCR) repertoire. In people living with HIV (PLWH), monitoring TCR repertoire is challenged by the inconsistency of complementarity determining region 3 (CDR3) and limited cell numbers in clinical samples. Thus, a quantitative method is necessary for monitoring the TCR repertoire in PLWH. We characterized the TCR V-J pairing profile of naïve and memory CD4+ T cells in healthy donors, HIV-infected antiretroviral therapy (ART)-naïve patients and long-term (over 5 years) ART-experienced patients by performing TCR sequencing. We developed a V-J index with 18 parameters which were subdivided into five categories (expression coverage, cumulative percentage of the top tenth percentile, diversity, intra-individual similarity and inter-individual similarity). In ART-naïve patients, 14 of the 18 parameters were significantly altered. Long-term ART recovered ten parameters. The four unrecovered parameters were related to inter-individual similarity. Therefore, these findings indicate that long-term ART could only partially recover TCR V-J pairs and introduce newly impacted V-J pairs. Moreover, these results provide new insights into the V-J pairing of the TCR and into the disturbance of TCR repertoire in HIV infection. Electronic Supplementary Material Supplementary material is available for this article at 10.1007/s11427-020-1718-2 and is accessible for authorized users.

Origin of replication (ori in theta-replicating plasmids or dso in rolling circle replicating plasmids) initiates plasmid replication in a broad range of bacteria. These two kinds of plasmids were both identified in Streptococcus, a genus composed of both human commensal bacteria and pathogens with the ability to cause severe community-acquired infections, including meningitides, septicemia, and respiratory tract diseases. Given the important roles of Streptococcus in the exchange of genetic elements with other symbiotic microbes, the genotypes and phenotypes of both Streptococcus spp. and other symbiotic species could be changed during colonization of the host. Therefore, an improved plasmid system is required to study the functional, complicated, and changeable genomes of Streptococcus. In this study, a dual-replicon shuttle vector system named pDRE was constructed to achieve heterologous gene expression. The vector system contained theta replicon for Escherichia coli. The origin of rolling circle replicon was synthesized according to pMV158 in Gram-positive bacteria. By measuring the products of inserted genes at multiple cloning sites, the ability of this vector system in the replication and expression of heterologous genes was assessed in four Streptococcus and three other Gram-positive bacteria: Bacillus subtilis, Lactococcus lactis, and Staphylococcus aureus. The results showed that the newly constructed vector could simultaneously replicate and express heterologous genes in a broad range of Gram-positive and Gram-negative bacteria, thus providing a potentially powerful genetic tool for further functional analysis.

We report the design, analysis, fabrication, and measurement of a quad-band microwave metamaterial absorber that exhibits four distinct high absorption peaks at specific resonance frequencies. The proposed structure consists of a metallic hexagonal patch layer on top of a dielectric substrate with a metallic film as bottom layer. The simulation and experimental results show that the absorber presents four distinctive perfect (>90%) absorption peaks up to incidence angle of 40° for both transverse electric and transverse magnetic modes. The results prove that this kind of quad-band absorber has good performance over a wide incidence angle range and is polarization insensitive. Moreover, the experimental and numerical simulation results are essentially in agreement.

The relationship between obstructive sleep apnea (OSA) and chronic rhinosinusitis (CRS) still remains unclear. This retrospective cohort study aimed to investigate the relationship between OSA and subsequent CRS using a population-based dataset. The study used data from the Taiwan Longitudinal Health Insurance Database 2005. We selected 971 patients with OSA for the study cohort and 4855 patients without OSA for the comparison cohort. Each patient was tracked for 5 years to determine those who were subsequently diagnosed with CRS. Stratified Cox proportional hazard regression analyses were performed to examine the association of OSA with subsequent CRS. The results revealed that 161 (2.76%) of the total sampled patients were subsequently diagnosed with CRS. Subsequent incidences of CRS were found in 64 (6.59%) patients with OSA and 97 (2.00%) patients without OSA. The adjusted hazard ratio (HR) of subsequent CRS for patients with OSA was 3.18 (95% confidence interval: 2.27~4.45) compared to those without OSA. Furthermore, the HR for CRS was similar for subjects with OSA for both genders (with an adjusted HR of 3.44 for males and 2.63 for females). We concluded that patients with OSA had a higher risk of subsequent CRS compared to patients without OSA regardless of sex.

GaMnN thin films were fabricated by using pulsed laser deposition followed by annealing. In our experiments, the impact of the background nitrogen pressure on the crystal quality, morphology and the ferromagnetism of the GaMnN thin films were studied systematically. It is found that the samples deposited at 0.75 Pa have the best crystal quality. All the annealed samples showed ferromagnetic behavior, and the Curie temperature was estimated up to 340 K. We found the magnetization of our samples changes depending on the concentration of Mn3+ ions, and the origin of the room temperature ferromagnetism of our samples can be explained by bound magnetic polaron theory. The nitrogen vacancies may cause the ferromagnetism to be weakened.

ZnMgO thin films have been deposited on Si(111) substrates by pulsed laser deposition (PLD) technique at growth temperature from 300 to 700°C in nitrogen ambient of 1.0 Pa. The effects of growth temperature on structural and optical properties of deposited ZnMgO thin films have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared absorption (IR) spectra and photoluminescence (PL) spectra. The results of XRD and SEM analyses show that the film fabricated at 400°C possesses good crystallinity with hexagonal wurtzite structure and surface morphology. The Mg has been incorporated into ZnO in the form of substitutional Zn. The IR spectra reveal the typical absorption peaks of ZnMgO. The band-gap values have been obtained from 2.96 to 4.23 eV with increasing growth temperature. The PL spectra show that the highest UV emission is obtained at growth temperature of 600°C, and the obvious blue-shift is observed. This may be assigned as the change of the band-gap due to the increasing incorporation of Mg2+ ions with the increasing growth temperature.

Investigation of the EtOH extract of Artemisia argyi leaves led to the isolation of six compounds (1-6). These structures were identified using spectroscopic methods, of which compound 1, (+)-artemisarin, is a new norneolignan, and 2-6 were isolated from this plant for the first time.

Linear porphyrin-thiophene copolymers were synthesized by linking 5, 15-positions of porphyrin with tetrathiophene or bithiophene moieties for preparing conducting polymer. 2,8,12,18-tetraethyl-3,7,13,17-tetramethyl-5, 15-dithienylporphyrin4a (45.1%), 5, 15-di-bithienyl- 2,8,12,18-tetraethyl-3, 7, 13, 17-tetramethylporphyrin4b (61. 2%) and their metal complexes were also reported in high yields (>90%) as the monomers. 5, 15-di-bithienylporphyrin and its metal complexes could be polymerized by oxidation using FeCl3 as oxidant. However, 5,15-dithienylporphyrin and its metal complexes can not be polymerized by same reaction. Their polymers were synthesized by electrochemical oxidation on the gold-plate electrode. The structures of copolymers were identified by elemental analysis and IR spectra. And the conductivity of poly 5,15-di-bithienylporphyrin was measured to reach over 1.0× 10−6S/cm.

Western Yunnan is located at the boundary of collision or underthrusting zone of Eurasian plate and is influenced by many times tectonic movements. With very complex geological environment and tectonic background, it is one of the seismically active areas. In the paper, the teleseismic records were selected from 16 national, local and mobile stations, including 4 very-wide-band mobile stations of PASSCAL. And nearly 2 000 receiver functions were extracted. Two measuring lines are 650 km and 450 km, respectively and across some major tectonic units in Western Yunnan. It is indicated that Nujiang might be a seam characterized by underthrusting. The western and eastern boundaries of Sichuan-Yunnan rhombus block, i.e., Honghe and Xiaojiang faults, might be an erection seam or collision belt. Panxi tectonic zone still has the characteristics of continental rift valley, that is, the surface is hollow and the upper mantle is upwarping. The tectonic situation in Western Yunnan is of certain regulation with the interlacing distribution of orogenic zone and seam. The crustal thickness decreases gradually from the north to the south and the S wave velocity is globally lower here.

Tengchong volcanic area is located near the impinging and underthrust margin of India and Eurasia plates. The volcanic activity is closely related to the tectonic environment. The deep structure characteristics are inferred from the receiver function inversion with the teleseismic records in the paper. The results show that the low velocity zone is influenced by the NE-trending Dayingjiang fault. The S-wave low velocity structure occurs obviously in the southern part of the fault, but unobviously in its northern part. There are low velocity zones in the shallow position, which coincides with the seismicity. It also demonstrates that the low velocity zone is directly related to the thermal activity in the volcanic area. Therefore, we consider that the volcano may be alive again.

The Wudalianchi volcano is a modern volcano erupted since the Holocene. Its frequent occurrence of the small earthquake is considered to be indicator of active dormancy volcano. The S wave velocity structure is inferred from the receiver function for the crust and upper mantle of the Wudalianchi volcano area. The results show that the low velocity structure of S wave is widely distributed underneath the volcano area and part of the low-velocity-zone located at shallow depth in the Wudalianchi volcano area. The low velocity structure is related to the seismicity. The Moho interface is not clear underneath the volcano area, which may be regard to be an necessary condition for the lava upwelling. Therefore, we infer that the Wudalianchi volcano has the deep structural condition for the volcano activity and may be alive again.