306 research outputs found

    Experimental high-intensity three-photon entangled source

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    We experimentally realize a high-intensity three-photon Greenberger-Horne-Zeilinger (GHZ) entanglement source directly following the proposal by Rarity and Tapster [J. G. Rarity and P. R. Tapster, Phys. Rev. A 59, R35 (1999)]. The threefold coincidence rate can be more than 200 Hz with a fidelity of 0.811, and the intensity can be further improved with moderate fidelity degradation. The GHZ entanglement is characterized by testing the Bell-Mermin inequality and using an entanglement witness operator. To optimize the polarization-entangled source, we theoretically analyze the relationship between the mean photon number of the single-photon source and the probability of parametric down-conversion.Comment: 4 pages, 4 figure

    ‘Zhengmei’: A new early-ripening table grape

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    Long-Term Nucleos(t)ide Analogues Therapy for Adults With Chronic Hepatitis B reduces the Risk of Long-Term Complications: a meta-analysis

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    <p>Abstract</p> <p>Background</p> <p>The effect of antiviral therapy in chronic hepatitis B (CHB) on reducing the risk of long-term complications (LTCs) remains unclear so far. To study whether long-term nucleos(t)ide analogues therapy can reduce the risk of long-term complications.</p> <p>Methods</p> <p>We searched MEDLINE, EMBASE, OVID, the Cochrane Central Register of Controlled Trials. Relative risks (RRs) of long-term complications with or without treatment were studied. Also subgroup analyses including the status of drug-resistance, HBeAg and pre-existing compensated cirrhosis were done using relative risks of long-term complications either with or without treatment or among nucleos(t)ide analogues treatment groups.</p> <p>Results</p> <p>Six eligible studies (3644 patients in all) were included. Data showed the incidence of long-term complications in treatment groups was induced by 74%(RR:0.26, 95% CI: 0.15-0.47) compared with no treatment. Whether drug-resistant happened or not during the long-term therapy, the incidence of long-term complications was still significantly induced respectively by 45%(RR: 0.55,95%CI:0.40-0.76) and 78% (RR:0.22, 95%CI: 0.13-0.36). For both different status of HBeAg and pre-existing compensated cirrhosis, there was significant lower incidence of long-term complications in treatment groups compared with no treatment, too. Moreover, among the NA treatment groups, patients with drug-resistance had 2.64 times (RR:2.64, 95%CI: 1.58-4.41) higher chance of developing to long-term complications, and patients with pre-existing compensated cirrhosis also had 3.07 times (RR:3.07, 95%CI: 1.04-9.11) higher chance of developing to long-term complications.</p> <p>Conclusions</p> <p>Long-term nucleos(t)ide analogue therapy for adults with CHB prevents or delays the development of long-term complications including decompensated cirrhosis, CHB-related death or CHB-related HCC in patients with CHB. The patients who need take antiviral drugs should receive the antiviral therapy as soon as possible.</p

    Research progress on influence of PM2.5 on allergic rhinitis

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    Allergic rhinitis (AR) is one of the main chronic inflammatory diseases that pose a global threat. Its symptoms persist for a long time, recur, and seriously affect the physical and mental health of the patients. Existing research has shown that the occurrence and development of AR are related to genetic and environmental factors. In recent years, the harm of air pollution to human health has received increasing attention, and fine particulate matter (PM2.5) is the main harmful component of air pollutants. Its small particle size makes it easy to absorb various harmful substances, enter the respiratory tract, damage the nasal mucosa, and participate in the occurrence and development process of AR. At present, a large number of epidemiological studies have confirmed that PM2.5 is positively related to the incidence rate and severity of symptoms of AR, but its exact mechanism is still unclear. Therefore, studying the mechanism of PM2.5 exposure on AR damage is expected to provide new clues for exploring the pathogenesis and deterioration of AR. This article reviewed the epidemiological studies and toxicological mechanisms of PM2.5 exposure and AR in recent years; discussed the potential biological mechanisms of PM2.5 induced AR occurrence and development, including nasal mucositis damage, oxidative stress, and immune damage. Furthermore, a new research direction was proposed, which suggested that neuroimmune disorders and bacterial imbalance may be involved in the progression of AR and play a certain role in the toxic effects induced by PM2.5. We aim to provide ideas and a theoretical basis for developing effective measures to prevent and treat AR

    Burst expansion, distribution and diversification of MITEs in the silkworm genome

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    <p>Abstract</p> <p>Background</p> <p>Miniature inverted-repeat transposable elements (MITEs) are widespread in plants and animals. Although silkworm (<it>Bombyx mori</it>) has a large amount of and a variety of transposable elements, the genome-wide information of the silkworm MITEs is unknown.</p> <p>Results</p> <p>We used structure-based and homology approaches to search for MITEs in the silkworm genome. We identified 17 MITE families with a total of 5785 members, accounting for ~0.4% of the genome. 7 of 17 MITE families are completely novel based on the nucleotide composition of target site duplication (TSD) and/or terminal inverted repeats (TIR). Silkworm MITEs were widely and nonrandom distributed in the genome. One family named BmMITE-2 might experience a recent burst expansion. Network and diversity analyses for each family revealed different diversification patterns of the silkworm MITEs, reflecting the signatures of genome-shocks that silkworm experienced. Most silkworm MITEs preferentially inserted into or near genes and BmMITE-11 that encodes a germline-restricted small RNA might silence its the closest genes in silkworm ovary through a small RNA pathway.</p> <p>Conclusions</p> <p>Silkworm harbors 17 MITE families. The silkworm MITEs preferred to reside in or near genes and one MITE might be involved in gene silence. Our results emphasize the exceptional role of MITEs in transcriptional regulation of genes and have general implications to understand interaction between MITEs and their host genome.</p
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