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Ground-penetrating radar (GPR) detects a tunnel with relatively low-frequency electromagnetic waves, which can result in poorly characterized reinforced steel bar (rebar) hyperbolas and make it challenging to recognize rebar. Thus, the rebar is located by using attenuation and reflection coefficients, and the hyperbolic feature of the rebar is reconstructed for recognition. Due to differences in the electromagnetic properties of rebar and other media in the second lining, the position of rebar in the one-dimensional time wave diagram (A-scan) is determined by using the attenuation and reflection coefficients. The rebar is recognized at the peak point in the A-scan. This peak point is in the opposite phase of the incident wave. The amplitude of these peaks is smaller than the peaks of the adjacent points. Then, these negative peak points are reconstructed on the two-dimensional scanning data (B-scan). Finally, the rebar is recognized by using the hyperbolic feature of the rebar. The method is applied in the Husa Tunnel in Yunnan Province, China. Moreover, in the mileage section YK81+506–YK81+542 of the Husa Tunnel, the hyperbolic feature of the reconstructed rebar is evident, and the rebar appears in the region of 5–7 ns in the B-scan. [ABSTRACT FROM AUTHOR]

The Yangla copper deposit, with Cu reserves of 1.2 Mt, is located between a series of thrust faults in the Jinshajiang-Lancangjiang-Nujiang region, Yunnan, China, and has been mined since 2007. Fluid inclusion trapping conditions ranged from 1.32 to 2.10 kbar at 373-409 °C. Laser Raman spectroscopy confirms that the vapour phase in these inclusions consists of CO, CH, N and HO. The gas phases in the inclusions are HO and CO, with minor amounts of N, O, CO, CH, CH, CH, and CH. Within the liquid phase, the main cations are Ca and Na while the main anions are SO and Cl. The oxygen and hydrogen isotope compositions of the ore-forming fluids (−3.05‰ ≤ δO ≤ 2.5‰; −100‰ ≤ δD ≤ −120‰) indicate that they were derived from magma and evolved by mixing with local meteoric water. The δS values of sulfides range from −4.20‰ to 1.85‰(average on −0.85‰), supporting a magmatic origin. Five molybdenite samples taken from the copper deposit yield a well-constrained Re-Os isochron age of 232.8 ± 2.4 Ma. Given that the Yangla granodiorite formed between 235.6 ± 1.2 Ma and 234.1 ± 1.2 Ma, the Cu metallogenesis is slightly younger than the crystallization age of the parent magma. A tectonic model that combines hydrothermal fluid flow and isotope compositions is proposed to explain the formation of the Yangla copper deposit. At first, westward subduction of the Jinshajiang Oceanic Plate in the Early Permian resulted in the development of a series of thrust faults. This was accompanied by fractional melting beneath the overriding plate, triggering magma ascent and extensive volcanism. The thrust faults, which were then placed under tension during a change in tectonic mode from compression to extension in the Late Triassic, formed favorable pathways for the magmatic ore-forming fluids. These fluids precipitated copper-sulfides to form the Yangla deposit. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To survey the prevalence and risk factors of HSV-2 among Chinese and Vietnamese female sex workers (FSW) in the border county of Hekou, Yunnan Province, China. Methods: A cross-sectional survey was conducted on demographics, sexual behavior, medical history, and drug use among FSWs. Laboratory samples were obtained to test for HSV-2 and other STIs such as HIV, Syphilis, Trichomonas vaginalis, Neisseria gonorrhoeae, Chlamydia trachomatis, Bacterial vaginosis, and Yeast infections. Cervicitis and genital warts were also diagnosed. Results: Of the 345 FSWs who participated in this study, 112 (32.5%) were ethnic Chinese and 233 (67.5) were Vietnamese. Among FSWs in Hekou, the prevalence rates were 58.3% for HSV-2, 5.5% for HIV, and 4.1% for bacterial vaginosis (BV). Age <21 (OR: 0.5; 95% CI: 0.3, 0.8), duration of commercial sex work ≤3 months (OR: 0.5; 95% CI: 0.3, 0.8), oral and vaginal sex with the last client (as opposed to only vaginal sex) (OR: 1.6; 95% CI: 1.0, 2.7), HIV (OR: 11.4; 95% CI: 1.5, 87.2), and bacterial vaginosis (BV) (OR: 5.6; 95% CI: 1.2, 26.9) were significantly correlated with HSV-2 infection. Conclusion: Multivariate analysis showed that several factors were significantly correlated with the high prevalence of HSV-2 in FSWs in the border area between China and Vietnam. Further studies and interventions are needed for HSV-2 epidemiology in the border area. [Copyright &y& Elsevier]

Abstract: The Yangla copper deposit, situated in the middle section of Jinshajiang tectonic belt between Zhongza–Zhongdian block and Changdu–Simao block, is a representative and giant copper deposit that has been discovered in Jinshajiang–Lancangjiang–Nujiang region in recent years. There are coupled relationships between Yangla granodiorite and copper mineralization in the Yangla copper deposit. Five molybdenite samples yielded a well-constrained 187Re-187Os isochron age of 233.3±3Ma, the metallogenesis is therefore slightly younger than the crystallization age of the granodiorite. S, Pb isotopic compositions of the Yangla copper deposit indicate that the ore-forming materials were derived from the mixture of upper crust and mantle, also with the magmatic contributions. In the late Early Permian, the Jinshajiang Oceanic plate was subducted to the west, resulting in the formation of a series of gently dipping thrust faults in the Jinshajiang tectonic belt, meanwhile, accompanied magmatic activities. In the early Late Triassic, which was a time of transition from collision-related compression to extension in the Jinshajiang tectonic belt, the thrust faults were tensional; it would have been a favorable environment for forming ore fluids. The ascending magma provided a channel for the ore-forming fluid from the mantle wedge. After the magma arrived at the base of the early-stage Yangla granodiorite, the platy granodiorite at the base of the body would have shielded the late-stage magma from the fluid. The magma would have cooled slowly, and some of the ore-forming fluid in the magma would have entered the gently dipping thrust faults near the Yangla granodiorite, resulting in mineralization. [Copyright &y& Elsevier]