原特提斯的消減極性:西昆侖128公里巖體的啟示

The Yirba (128 km) pluton is an early Paleozoic dioritic intrusion of western Kunlun orogenic belt, northwest China as an important element when reconstructing the evolution history of this belt. Due to the scarcity of field data and methodological difference in studying this pluton, however, no consensus for its age, source and tectonic setting has been adopted. In this paper, we present new geochronological and geochemical data for the Yirba pluton, aiming to better understand its age, source, and hence the early Paleozoic tectonic evolutionary history of western Kunlun. U-Pb data by single grain zircon analyses suggest that the Yirba pluton was emplaced 471 ± 5 Ma ago and contains ca. 490 Ma zircon grains inherited from source, or captured in the magma chamber. The pluton is enriched in Al 2 O 3 (15.7% ∼ 18.4%), Sr (470 ∼ 864 μg/g) and other LILEs (large ion lithosphile elements), but relatively depleted in HFSE (high field strength elements and HREE), with LREE-enriched patterns and low to medium europium anomalies (δEu = ∼ 0.7), showing typical characteristics of I-type, volcanic arc granitoids. Although its relatively high Al 2 O 3, Sr and low MgO contents make it resemble adakite, its relatively high Yb (1.92 ∼ 2.88 μg/g), Y (19.4 ∼ 34.0 μg/g) contents, low Sr/Y (24.2 ∼ 37.0) , Zr/Sm (7.3 ∼ 21) and relatively high initial Sr isotope ratios (0.7075 ∼ 0.7091) do not support a subducting slab origin. Its Nd model ages (1.06 ∼ 1.35 Ga) indicate a juvenile source, while its O isotope compositions (+5.7‰ ∼ + 7.4‰) and Sr-O isotope relationship preclude significant involvement of sialic materials. The major, trace, REE and Nd-Sr-O isotope compositions strongly suggest that the Yirba pluton was formed by partial melting of mafic lower crust in a southward growing, active continental margin environment. The existence of volcanic arc granitoids in the south margin of the North Kunlun terrane suggests that the subduction polarity of the Proto-Tethys was northward.128公里巖體是西昆侖造山帶中一個早古生代的花崗閃長巖體,長期以來一直是研究西昆侖構造演化的重要參考依據。然而由于區域地質資料的不足和研究手段的不同,對該巖體的形成年代、源區性質以及構造背景等方面還存在著不同的認識。本文試圖通過地質年代學和地球化學方面的研究,明確128公里巖體的成巖時代和構造背景,進而制約西昆侖的早古生代構造演化。單顆粒鋯石的U-Pb定年結果表明128公里巖體形成于471±5 Ma并含有可能形成于早期巖漿房或繼承自源區的490 Ma左右的鋯石。128公里巖體富Al_2O_3(15.7％～18.4％),Sr(470～864μg/g)和大離子親石元素但相對虧損 高場強元素,相對富集輕稀土且具有低到中等的負銪異常(δEu=～0.7),顯示出典型的Ⅰ型弧花崗巖特征。盡管其富集Al_2O_3、Sr、相對低的MgO含量和Y/Yb比值使其非常類似于埃達克巖,但其相對高的Yb(1.92～2.88μg/g)、Y(19.4～34.0μg/g)含量,低的Sr/Y(24.2～37.0)和Zr/Sm(7.3～21)比值以及相對高的初始Sr同位素組成(0.7075～0.7091)排除了消減板塊在石榴石穩定區發生部分熔融的可能性。低的氧同位素组成( + 5.7％～7.4％) 以及Sr-O 同位素关系表明该岩体并非形成于地慢来源的岩泉与变质围岩间的同化混染。高的稀土含量、明显的稀土分馏以及相对高的Sr 同位素组成表明12 8 公里岩体不大可能形成于受陆源物质影响较小的大洋岛弧, 而更可能形成于活动大陆边缘环境中基性地壳物质的部分熔融。北昆仑地体的南缘存在火山弧型花岗岩的事实表明, 原特提斯的消减方向应当是向北的。published_or_final_versio

Ethnic differences in susceptibilities to A(H1N1) flu: An epidemic parameter indicating a weak viral virulence

The current A(H1N1) flu has showed sub-population dependent susceptibility and fatality as early as April and May of 2009 in its first wave of spreading. After the pandemic outbreak spreads globally for more than seven months, the subpopulation dependence of this flu, including ethnicity, age and genderselectivity, has been recognized by several research groups. This paper attempts to discussed how to identify ethnic selectivity from the released data by WHO relevant to this ongoing flu, review some recently published papers describing the presence of ethnic differences in susceptibilities to the H1N1flu virus and further raised an argument that ethnic differences in  susceptibilities to a virus might be a piece of evidence reflecting a weak virulence of that specific virus

Disparities and risks of sexually transmissible infections among men who have sex with men in China: a meta-analysis and data synthesis.

BACKGROUND: Sexually transmitted infections (STIs), including Hepatitis B and C virus, are emerging public health risks in China, especially among men who have sex with men (MSM). This study aims to assess the magnitude and risks of STIs among Chinese MSM. METHODS: Chinese and English peer-reviewed articles were searched in five electronic databases from January 2000 to February 2013. Pooled prevalence estimates for each STI infection were calculated using meta-analysis. Infection risks of STIs in MSM, HIV-positive MSM and male sex workers (MSW) were obtained. This review followed the PRISMA guidelines and was registered in PROSPERO. RESULTS: Eighty-eight articles (11 in English and 77 in Chinese) investigating 35,203 MSM in 28 provinces were included in this review. The prevalence levels of STIs among MSM were 6.3% (95% CI: 3.5-11.0%) for chlamydia, 1.5% (0.7-2.9%) for genital wart, 1.9% (1.3-2.7%) for gonorrhoea, 8.9% (7.8-10.2%) for hepatitis B (HBV), 1.2% (1.0-1.6%) for hepatitis C (HCV), 66.3% (57.4-74.1%) for human papillomavirus (HPV), 10.6% (6.2-17.6%) for herpes simplex virus (HSV-2) and 4.3% (3.2-5.8%) for Ureaplasma urealyticum. HIV-positive MSM have consistently higher odds of all these infections than the broader MSM population. As a subgroup of MSM, MSW were 2.5 (1.4-4.7), 5.7 (2.7-12.3), and 2.2 (1.4-3.7) times more likely to be infected with chlamydia, gonorrhoea and HCV than the broader MSM population, respectively. CONCLUSION: Prevalence levels of STIs among MSW were significantly higher than the broader MSM population. Co-infection of HIV and STIs were prevalent among Chinese MSM. Integration of HIV and STIs healthcare and surveillance systems is essential in providing effective HIV/STIs preventive measures and treatments. TRIAL REGISTRATION: PROSPERO NO: CRD42013003721

Determination of the number of J/ψ events with J/ψ → inclusive decays

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Higher-order multipole amplitude measurement in ψ ′→γχ c2

Using 106×106 ψ ′ events collected with the BESIII detector at the BEPCII storage ring, the higher-order multipole amplitudes in the radiative transition ψ ′→γχ c2→γπ +π -/γK +K - are measured. A fit to the χ c2 production and decay angular distributions yields M2=0.046±0. 010±0.013 and E3=0.015±0.008±0.018, where the first errors are statistical and the second systematic. Here M2 denotes the normalized magnetic quadrupole amplitude and E3 the normalized electric octupole amplitude. This measurement shows evidence for the existence of the M2 signal with 4.4σ statistical significance and is consistent with the charm quark having no anomalous magnetic moment. © 2011 American Physical Society.published_or_final_versio

Two-photon widths of the χ c0,2 states and helicity analysis for χ c2→γγ

Based on a data sample of 106×106 ψ ′ events collected with the BESIII detector, the decays ψ ′→γχ c0,2, χ c0,2→γγ are studied to determine the two-photon widths of the χ c0,2 states. The two-photon decay branching fractions are determined to be B(χ c0→γγ)=(2. 24±0.19±0.12±0.08)×10 -4 and B(χ c2→γγ)=(3.21±0.18±0. 17±0.13)×10 -4. From these, the two-photon widths are determined to be Γ γγ(χ c0)=(2. 33±0.20±0.13±0.17)keV, Γ γγ(χ c2)=(0.63±0.04±0. 04±0.04)keV, and R=Γ γγ(χ c2)/ Γ γγ(χ c0)=0.271±0. 029±0.013±0.027, where the uncertainties are statistical, systematic, and those from the PDG B(ψ ′→γχ c0,2) and Γ(χ c0,2) errors, respectively. The ratio of the two-photon widths for helicity λ=0 and helicity λ=2 components in the decay χ c2→γγ is measured for the first time to be f 0/2=Γγγλ= 0(χ c2)/Γγγλ=2(χ c2)=0. 00±0.02±0.02. © 2012 American Physical Society.published_or_final_versio

Bilateral downregulation of Nav1.8 in dorsal root ganglia of rats with bone cancer pain induced by inoculation with Walker 256 breast tumor cells

<p>Abstract</p> <p>Background</p> <p>Rapid and effective treatment of cancer-induced bone pain remains a clinical challenge and patients with bone metastasis are more likely to experience severe pain. The voltage-gated sodium channel Nav1.8 plays a critical role in many aspects of nociceptor function. Therefore, we characterized a rat model of cancer pain and investigated the potential role of Nav1.8.</p> <p>Methods</p> <p>Adult female Wistar rats were used for the study. Cancer pain was induced by inoculation of Walker 256 breast carcinosarcoma cells into the tibia. After surgery, mechanical and thermal hyperalgesia and ambulation scores were evaluated to identify pain-related behavior. We used real-time RT-PCR to determine Nav1.8 mRNA expression in bilateral L4/L5 dorsal root ganglia (DRG) at 16-19 days after surgery. Western blotting and immunofluorescence were used to compare the expression and distribution of Nav1.8 in L4/L5 DRG between tumor-bearing and sham rats. Antisense oligodeoxynucleotides (ODNs) against Nav1.8 were administered intrathecally at 14-16 days after surgery to knock down Nav1.8 protein expression and changes in pain-related behavior were observed.</p> <p>Results</p> <p>Tumor-bearing rats exhibited mechanical hyperalgesia and ambulatory-evoked pain from day 7 after inoculation of Walker 256 cells. In the advanced stage of cancer pain (days 16-19 after surgery), normalized Nav1.8 mRNA levels assessed by real-time RT-PCR were significantly lower in ipsilateral L4/L5 DRG of tumor-bearing rats compared with the sham group. Western-blot showed that the total expression of Nav1.8 protein significantly decreased bilaterally in DRG of tumor-bearing rats. Furthermore, as revealed by immunofluorescence, only the expression of Nav1.8 protein in small neurons down regulated significantly in bilateral DRG of cancer pain rats. After administration of antisense ODNs against Nav1.8, Nav1.8 protein expression decreased significantly and tumor-bearing rats showed alleviated mechanical hyperalgesia and ambulatory-evoked pain.</p> <p>Conclusions</p> <p>These findings suggest that Nav1.8 plays a role in the development and maintenance of bone cancer pain.</p

COVID-19 vaccine-readiness for anti-CD20-depleting therapy in autoimmune diseases

Although most autoimmune diseases are considered to be CD4 T cell- or antibody-mediated, many respond to CD20-depleting antibodies that have limited influence on CD4 and plasma cells. This includes rituximab, oblinutuzumab and ofatumumab that are used in cancer, rheumatoid arthritis and off-label in a large number of other autoimmunities and ocrelizumab in multiple sclerosis. Recently, the COVID-19 pandemic created concerns about immunosuppression in autoimmunity, leading to cessation or a delay in immunotherapy treatments. However, based on the known and emerging biology of autoimmunity and COVID-19, it was hypothesised that while B cell depletion should not necessarily expose people to severe SARS-CoV-2-related issues, it may inhibit protective immunity following infection and vaccination. As such, drug-induced B cell subset inhibition, that controls at least some autoimmunities, would not influence innate and CD8 T cell responses, which are central to SARS-CoV-2 elimination, nor the hypercoagulation and innate inflammation causing severe morbidity. This is supported clinically, as the majority of SARS-CoV-2-infected, CD20-depleted people with autoimmunity have recovered. However, protective neutralizing antibody and vaccination responses are predicted to be blunted until naive B cells repopulate, based on B cell repopulation kinetics and vaccination responses, from published rituximab and unpublished ocrelizumab (NCT00676715, NCT02545868) trial data, shown here. This suggests that it may be possible to undertake dose interruption to maintain inflammatory disease control, while allowing effective vaccination against SARS-CoV-29, if and when an effective vaccine is available

High Prevalence and Genetic Diversity of HCV among HIV-1 Infected People from Various High-Risk Groups in China

BACKGROUND: Co-infection with HIV-1 and HCV is a significant global public health problem and a major consideration for anti-HIV-1 treatment. HCV infection among HIV-1 positive people who are eligible for the newly launched nationwide anti-HIV-1 treatment program in China has not been well characterized. METHODOLOGY: A nationwide survey of HIV-1 positive injection drug uses (IDU), former paid blood donors (FBD), and sexually transmitted cases from multiple provinces including the four most affected provinces in China was conducted. HCV prevalence and genetic diversity were determined. We found that IDU and FBD have extremely high rates of HCV infection (97% and 93%, respectively). Surprisingly, people who acquired HIV-1 through sexual contact also had a higher rate of HCV infection (20%) than the general population. HIV-1 subtype and HCV genotypes were amazingly similar among FBD from multiple provinces stretching from Central to Northeast China. However, although patterns of overland trafficking of heroin and distinct HIV-1 subtypes could be detected among IDU, HCV genotypes of IDU were more diverse and exhibited significant regional differences. CONCLUSION: Emerging HIV-1 and HCV co-infection and possible sexual transmission of HCV in China require urgent prevention measures and should be taken into consideration in the nationwide antiretroviral treatment program