How Placenta Promotes the Successful Reproduction in High-Altitude Populations: A Transcriptome Comparison between Adaptation and Acclimatization.

As the best adapted high altitude population, Tibetans feature a relatively high offspring survival rate. Genome-wide studies have identified hundreds of candidate SNPs related to high altitude adaptation of Tibetans, although most of them have unknown functional relevance. To explore the mechanisms behind successful reproduction at high altitudes, we compared the placental transcriptomes of Tibetans, sea level Hans (SLHan), and Han immigrants (ImHan). Among the three populations, placentas from ImHan showed a hyperactive gene expression pattern. Their increased activation demonstrates a hypoxic stress response similar to sea level individuals experiencing hypoxic conditions. Unlike ImHan, Tibetan placentas were characterized by the significant up-regulation of placenta-specific genes, and the activation of autophagy and the tricarboxylic acid (TCA) cycle. Certain conserved hypoxia response functions, including the antioxidant system and angiogenesis, were activated in both ImHan and Tibetans, but mediated by different genes. The coherence of specific transcriptome features linked to possible genetic contribution was observed in Tibetans. Furthermore, we identified a novel Tibetan-specific EPAS1 isoform with a partial deletion at exon six, which may be involved in the adaption to hypoxia through the EPAS1-centred gene network in the placenta. Overall, our results show that the placenta grants successful pregnancies in Tibetans by strengthening the natural functions of the placenta itself. On the other hand, the placenta of ImHan was in an inhabiting time-dependent acclimatization process representing a common hypoxic stress response pattern.

High-efficiency mode-locked erbium-doped ZBLAN fiber laser around 2.8 µm by directly depositing Bi2S3 particles onto a cavity mirror.

Mid-infrared (MIR) pulsed lasers near a 3 µm waveband show great potential for the high absorption of water molecules and many important gas molecules. A passively Q-switched mode-locked (QSML) E r 3+-doped fluoride fiber laser with a low laser threshold and high slope efficiency around a 2.8 µm waveband is reported. The improvement is achieved by depositing bismuth sulfide (B i 2 S 3) particles onto the cavity mirror directly as a saturable absorber and using the cleaved end of the fluoride fiber as output directly. -QSML pulses begin to appear with the pump power of 280 mW. The repetition rate of the QSML pulses reaches a maximum of 33.59 kHz with the pump power of 540 mW. When the pump power is further increased, the output of the fiber laser switches from the QSML to the continuous-wave mode-locked operation with the repetition rate of 28.64 MHz and the slope efficiency of 12.2%. The results indicate that B i 2 S 3 is a promising modulator for the pulsed lasers near a 3 µm waveband, which paves the way for further development of various applications in MIR wavebands, including material processing, MIR frequency combs, and modern healthcare.

Simulation and analysis of supercontinuum generation in the waveband up to 25 µm.

The ultra-wideband supercontinuum generation (SCG) in a Te-based chalcogenide (ChG) photonic crystal fiber (PCF) is simulated in the mid-infrared (MIR) waveband. The PCF core and cladding materials are Ge20As20Se15Te45 and Ge20As20Se17Te43, respectively. The supercontinuum (SC) broadening affected by the core diameter and fiber absorption is considered. The selected PCFs at different pumping wavelengths can demonstrate the generation of ultra-wideband MIR supercontinuum according to the simulated results. We consider SC broadening with and without fiber absorption. A SC range from 3 to 25 µm is demonstrated by simulation in a PCF with a core diameter of 8 µm and a pump wavelength of 6 µm considering the fiber absorption. With the increase of the peak power and the pulse width and the decrease of the core diameter, the degree of coherence gradually degraded. To the best of our knowledge, this is the first demonstration of the possibility of SCG up to the waveband of 25 µm in fiber. Our results highlight the potential of a novel Te-based chalcogenide multi-material PCF for SCG. We also provide a way to generate the SCs to longer wavebands than 20 µm in fiber, especially up to the far-infrared waveband.

Comparison of Different Linewidth Measuring Methods for Narrow Linewidth Laser.

We experimentally demonstrate a fiber laser with different linewidths based on self-injection locking (SIL) and the stimulated Brillouin scattering effect. Based on the homemade fiber laser, the error origin, resolution, and applicable range of delayed self-heterodyne interferometry (DSHI), self-correlation envelope linewidth detection (SCELD) and Voigt fitting are investigated numerically and experimentally. The selection of the linewidth measuring method should meet the following conclusions: an approximately Lorentzian self-heterodyne spectrum without the pedestal and high-intensity sinusoidal jitter is a prerequisite for DSHI; the SCELD needs a suitable length of delay fiber for eliminating flicker noise and dark noise of the electrical spectrum analyzer; a non-Lorentzian self-heterodyne spectrum without a pedestal is an indispensable element for Voigt fitting. According to the experimental results, the laser Lorentzian linewidth of SIL changes from 1.7 kHz to 587 Hz under different injection powers. When the Brillouin erbium fiber laser is utilized, the Lorentzian linewidth is measured to be 60 ± 5 Hz.

Changes of Mycobacterium tuberculosis specific antigen-stimulated CD27-CD38+IFN-γ+CD4+ T cells before and after anti-tuberculosis treatment.

BACKGROUND: The aim of the study was to investigate whether the expression of CD27-CD38+ in interferon (IFN)-γ+CD4+ T cells stimulated by the specific antigen early secreted antigenic target-6 (ESAT-6)/culture filter protein-10 (CFP-10) could be a potential new therapeutic evaluation indicator for anti-tuberculosis (TB) treatment. METHODS: Newly diagnosed active pulmonary TB patients, latent TB infection (LTBI) and healthy controls were enrolled from January 2021 to December 2021. PTB patients were treated by standard anti-TB regimen 2HREZ/4HR (2 months of isoniazid (H), rifampin (R), ethambutol (E), and pyrazinamide (Z) followed by 4 months of isoniazid (H) and rifampin (R)). The difference of CD27-CD38+ expression in IFN-γ+CD4+ T cells before treatment, 2 months after treatment, and 6 months after treatment were compared. RESULTS: Total 45 PTB patients, 38 LTBI cases and 43 healthy controls were enrolled. The expression of CD27-CD38+ decreased significantly after anti-TB treatment and was comparable with that in LTBI and healthy controls when the 6-month anti-TB treatment course was completed. The decline rate of CD27-CD38+ between 6 months after treatment and baseline was positively correlated with erythrocyte sedimentation rate (r = 0.766, P < 0.0001), C-reactive protein (r = 0.560, P = 0.003) and chest computerized tomography severity score (r = 0.632, P = 0.0005). The area under receiver operator characteristic curve of CD27-CD38+ in distinguish pulmonary TB patients before and after treatment was 0.779. CONCLUSION: The expression of CD27-CD38+ in ESAT-6/CFP-10 stimulated IFN-γ+CD4+T cells can well reflect the changes of the disease before and after anti-TB treatment, which is expected to be a potential new therapeutic evaluation index. Clinical Registry number chiCTR1800019966.