We report the first measurement of absolute hadronic branching fractions of Λ_{c}^{+} baryon at the Λ_{c}^{+}Λover ¯_{c}^{-} production threshold, in the 30 years since the Λ_{c}^{+} discovery. In ...total, 12 Cabibbo-favored Λ_{c}^{+} hadronic decay modes are analyzed with a double-tag technique, based on a sample of 567 pb^{-1} of e^{+}e^{-} collisions at sqrts=4.599 GeV recorded with the BESIII detector. A global least-squares fitter is utilized to improve the measured precision. Among the measurements for twelve Λ_{c}^{+} decay modes, the branching fraction for Λ_{c}^{+}→pK^{-}π^{+} is determined to be (5.84±0.27±0.23)%, where the first uncertainty is statistical and the second is systematic. In addition, the measurements of the branching fractions of the other 11 Cabibbo-favored hadronic decay modes are significantly improved.
Severe acute respiratory syndrome (SARS) is a new infectious disease with a global impact. Understanding its pathogenesis and developing specific diagnostic methods for its early diagnosis are ...crucial for the effective management and control of this disease. By using proteomic technology, truncated forms of α1‐antitrypsin (TF‐α1‐AT) were found to increase significantly and consistently in sera of SARS patients compared to control subjects. The result showed a sensitivity of 100% for SARS patients and a specificity of 92.8% for controls. Furthermore, the levels of these proteins significantly correlated with certain clinico‐pathological parameters. The dramatic increase in TF‐α1‐AT may be the result of degradation of α1‐AT. As α1‐AT plays an important role in the protection of lung function, its degradation may be an important factor in the pathogenesis of SARS. These findings indicate that increased TF‐α1‐AT may be therapeutically relevant, and may also be a useful biological marker for the diagnosis of SARS.
Haze has been severely affecting the densely populated areas in China
recently. While many of the efforts have been devoted to investigating the
impact of local anthropogenic emission, limited ...attention has been paid to
the contribution from long-range transport. In this study, we apply
simulations from six participating models supplied through the Task Force on
Hemispheric Transport of Air Pollution phase 2 (HTAP2) exercise to
investigate the long-range transport impact of Europe (EUR) and
Russia–Belarus–Ukraine (RBU) on the surface air quality in eastern Asia
(EAS), with special focus on their contributions during the haze episodes in
China. The impact of 20 % anthropogenic emission perturbation from the
source region is extrapolated by a factor of 5 to estimate the full impact.
We find that the full impacts from EUR and RBU are 0.99 µg m−3
(3.1 %) and 1.32 µg m−3 (4.1 %) during haze episodes,
while the annual averaged full impacts are only 0.35 µg m−3
(1.7 %) and 0.53 µg m−3 (2.6 %). By estimating the aerosol
response within and above the planetary boundary layer (PBL), we find that
long-range transport from EUR within the PBL contributes to 22–38 % of the
total column density of aerosol response in EAS. Comparison with the HTAP
phase 1 (HTAP1) assessment reveals that from 2000 to 2010, the long-range
transport from Europe to eastern Asia has decreased significantly by a factor
of 2–10 for surface aerosol mass concentration due to the simultaneous
emission reduction in source regions and emission increase in the receptor
region. We also find the long-range transport from the Europe and RBU regions
increases the number of haze events in China by 0.15 % and 0.11 %, and
the North China Plain and southeastern China has 1–3 extra haze days (<3 %). This study is the first investigation into the contribution of
long-range transport to haze in China with multi-model experiments.
Motivation: Estimation of misclassification error has received increasing attention in clinical diagnosis and bioinformatics studies, especially in small sample studies with microarray data. Current ...error estimation methods are not satisfactory because they either have large variability (such as leave-one-out cross-validation) or large bias (such as resubstitution and leave-one-out bootstrap). While small sample size remains one of the key features of costly clinical investigations or of microarray studies that have limited resources in funding, time and tissue materials, accurate and easy-to-implement error estimation methods for small samples are desirable and will be beneficial. Results: A bootstrap cross-validation method is studied. It achieves accurate error estimation through a simple procedure with bootstrap resampling and only costs computer CPU time. Simulation studies and applications to microarray data demonstrate that it performs consistently better than its competitors. This method possesses several attractive properties: (1) it is implemented through a simple procedure; (2) it performs well for small samples with sample size, as small as 16; (3) it is not restricted to any particular classification rules and thus applies to many parametric or non-parametric methods. Contact: wfu@stat.tamu.edu
Through a hydrothermal reaction route, zinc tungstate (ZnWO4) crystals with various morphologies and particle sizes were synthesised using sodium tungstate and zinc acetate as the raw materials. ...Eu3+-doped ZnWO4 was also obtained from hydrothermal systems and the photoluminescent properties of the products were investigated. Significant energy transfer from WO4(2-) groups to Eu3+ ions was observed. 16 refs.
Ovarian carcinoma anti-idiotypic antibody 6B11 was murine derived; we previously have cloned 6B11 single-chain Fv antibody (6B11ScFv) and constructed the 6B11ScFv/human granulocyte-macrophage colony ...stimulating factor (GM-CSF) fusion protein (designated as 6B11GM) to enhance the immunogenecity of the single-chain Ab(2). Because of the difference in species specificity between human GM-CSF and murine GM-CSF, there is no immune competent animal model on which the effect and metabolism of 6B11GM as a vaccine could be observed. In this study, 6B11mGM fusion gene was constructed by the fusing murine GM-CSF cDNA gene with 6B11ScFv. The fusion gene was cloned and expressed. The product of this gene is a fusion protein. It could specifically interact with the primary anti-ovarian carcinoma monoclonal antibody (COC166-9) and rat anti-mouse GM-CSF monoclonal antibody, respectively, and stimulate the growth of NFS-60 cells (a murine GM-CSF-dependent cell line). The specific anti-tumor immune response could be induced in BALB/c mice after immunized with anti-idiotypic fusion protein instead of ovarian carcinoma antigen without carrier proteins and adjuvant. Ab(3) could be detected in the sera of immunized mice with 6B11mGM by enzyme-linked immunoadsorbent assay test. Moreover, the fusion protein stimulated proliferation of CD4+ T cell from the spleen of BALB/c mice and proliferation of CD8+ T cell to a lesser degree. Therefore, 6B11mGM probably induces both humoral and cellular immunity against ovarian carcinoma in vivo.
Using a low background data sample of 9.7×10^{5} J/ψ→γη^{'}, η^{'}→γπ^{+}π^{-} events, which are 2 orders of magnitude larger than those from the previous experiments, recorded with the BESIII ...detector at BEPCII, the decay dynamics of η^{'}→γπ^{+}π^{-} are studied with both model-dependent and model-independent approaches. The contributions of ω and the ρ(770)-ω interference are observed for the first time in the decays η^{'}→γπ^{+}π^{-} in both approaches. Additionally, a contribution from the box anomaly or the ρ(1450) resonance is required in the model-dependent approach, while the process specific part of the decay amplitude is determined in the model-independent approach.
Background: Retinopathy of prematurity (ROP) is a vision-threatening disease in premature infants. Serum adiponectin (APN) concentrations positively correlate with postnatal growth and gestational ...age, important risk factors for ROP development. Dietary ω-3 (n–3) long-chain polyunsaturated fatty acids (ω-3 LCPUFAs) suppress ROP and oxygen-induced retinopathy (OIR) in a mouse model of human ROP, but the mechanism is not fully understood. Objective: We examined the role of APN in ROP development and whether circulating APN concentrations are increased by dietary ω-3 LCPUFAs to mediate the protective effect in ROP. Design: Serum APN concentrations were correlated with ROP development and serum ω-3 LCPUFA concentrations in preterm infants. Mouse OIR was then used to determine whether ω-3 LCPUFA supplementation increases serum APN concentrations, which then suppress retinopathy. Results: We found that in preterm infants, low serum APN concentrations positively correlate with ROP, and serum APN concentrations positively correlate with serum ω-3 LCPUFA concentrations. In mouse OIR, serum total APN and bioactive high-molecular-weight APN concentrations are increased by ω-3 LCPUFA feed. White adipose tissue, where APN is produced and assembled in the endoplasmic reticulum, is the major source of serum APN. In mouse OIR, adipose endoplasmic reticulum stress is increased, and APN production is suppressed. ω-3 LCPUFA feed in mice increases APN production by reducing adipose endoplasmic reticulum stress markers. Dietary ω-3 LCPUFA suppression of neovascularization is reduced from 70% to 10% with APN deficiency. APN receptors localize in the retina, particularly to pathologic neovessels. Conclusion: Our findings suggest that increasing APN by ω-3 LCPUFA supplementation in total parental nutrition for preterm infants may suppress ROP.
Undecylprodigiosin (UP) is a bacterial bioactive metabolite produced by
Streptomyces and
Serratia. In this study, we explored the anticancer effect of UP. Human breast carcinoma cell lines BT-20, ...MCF-7, MDA-MB-231 and T47D and one nonmalignant human breast epithelial cell line, MCF-10A, were tested in this study. We found that UP exerted a potent cytotoxicity against all breast carcinoma cell lines in a dose- and time-dependent manner. In contrast, UP showed limited toxicity to MCF-10A cells, indicating UP's cytotoxic effect is selective for malignant cells. UP's cytotoxic effect was due to apoptosis, as confirmed by positive TUNEL signals, annexin V-binding, caspase 9 activation and PARP cleavage. Notably, UP-induced apoptosis was blocked by the pan-caspase inhibitor z-VAD.fmk, further indicating the involvement of caspase activity. Moreover, UP caused a marked decrease of the levels of antiapoptotic BCL-X
L, Survivin and XIAP while enhancing the levels of proapoptotic BIK, BIM, MCL-1S and NOXA, consequently favoring induction of apoptosis. Additionally, we found that cells with functional p53 (MCF-7, T47D) or mutant p53 (BT-20, MDA-MB-231) were both susceptible to UP's cytotoxicity. Importantly, UP was able to induce apoptosis in MCF-7 cells with p53 knockdown by RNA interference, confirming the dispensability of p53 in UP-induced apoptosis. Overall, our results establish that UP induces p53-independent apoptosis in breast carcinoma cells with no marked toxicity to nonmalignant cells, raising the possibility of its use as a new chemotherapeutic drug for breast cancer irrespective of p53 status.
Corona cooling was detected previously from stacking a series of short type I bursts that occurred during the low/hard state of an atoll outburst. Type I bursts are hence regarded as sharp probes ...used to better our understanding of the basic properties of the corona. The first Chinese X-ray satellite, Insight-HXMT, has a large detection area at hard X-rays that provides a unique opportunity to move further in this research field. We report the first detection of corona cooling by Insight-HXMT from a single short type I burst appearing during the flare of 4U 1636-536. This type I X-ray burst has a duration of ∼13 s and hard X-ray shortage is detected with a significance of 6.2 in 40-70 keV. A cross-correlation analysis between the light curves of the soft and hard X-ray band shows that the corona shortage lags the burst emission by 1.6 1.2 s. These results are consistent with those derived previously from stacking a large amount of bursts detected by RXTE/PCA within a series of flares of 4U 1636-536. Moreover, the broad bandwidth of Insight-HXMT also allows, for the first time, one to infer the burst influence upon the continuum spectrum via performing the spectral fitting of the burst, which points to the finding that hard X-ray shortage appears at around 40 keV in the continuum spectrum. These results suggest that the evolution of the corona, along with the outburst/flare of NS XRB, may be traced via analyzing a series of embedded type I bursts using Insight-HXMT.
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