50 research outputs found

    Tailoring Single and Multiphoton Probabilities of a Single Photon On-Demand Source

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    As typically implemented, single photon sources cannot be made to produce single photons with high probability, while simultaneously suppressing the probability of yielding two or more photons. Because of this, single photon sources cannot really produce single photons on demand. We describe a multiplexed system that allows the probabilities of producing one and more photons to be adjusted independently, enabling a much better approximation of a source of single photons on demand.Comment: 4 pages, LaTex, 2 figures, twocolumn and RevTex Style for PR

    An intranasal vaccine durably protects against SARS-CoV-2 variants in mice

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    SARS-CoV-2 variants that attenuate antibody neutralization could jeopardize vaccine efficacy. We recently reported the protective activity of an intranasally administered spike protein-based chimpanzee adenovirus-vectored vaccine (ChAd-SARS-CoV-2-S) in animals, which has advanced to human trials. Here, we assessed its durability, dose response, and cross-protective activity in mice. A single intranasal dose of ChAd-SARS-CoV-2-S induced durably high neutralizing and Fc effector antibody responses in serum and S-specific IgG and IgA secreting long-lived plasma cells in the bone marrow. Protection against a historical SARS-CoV-2 strain was observed across a 100-fold vaccine dose range and over a 200-day period. At 6 weeks or 9 months after vaccination, serum antibodies neutralized SARS-CoV-2 strains with B.1.351, B.1.1.28, and B.1.617.1 spike proteins and conferred almost complete protection in the upper and lower respiratory tracts after challenge with variant viruses. Thus, in mice, intranasal immunization with ChAd-SARS-CoV-2-S provides durable protection against historical and emerging SARS-CoV-2 strains

    Improved protocols of secure quantum communication using W states

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    Recently, Hwang et al. [Eur. Phys. J. D. 61, 785 (2011)] and Yuan et al. [Int. J. Theo. Phys. 50, 2403 (2011)] have proposed two efficient protocols of secure quantum communication using 3-qubit and 4-qubit symmetric W state respectively. These two dense coding based protocols are generalized and their efficiencies are considerably improved. Simple bounds on the qubit efficiency of deterministic secure quantum communication (DSQC) and quantum secure direct communication (QSDC) protocols are obtained and it is shown that dense coding is not essential for designing of maximally efficient DSQC and QSDC protocols. This fact is used to design maximally efficient protocols of DSQC and QSDC using 3-qubit and 4-qubit W states.Comment: 8 page

    Pooled analysis of prospective cohort studies on height, weight, and breast cancer risk

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    The association between anthropometric indices and the risk of breast cancer was analyzed using pooled data from seven prospective cohort studies. Together, these cohorts comprise 337,819 women and 4,385 incident invasive breast cancer cases. In multivariate analyses controlling for reproductive, dietary, and other risk factors, the pooled relative risk (RR) of breast cancer per height increment of 5 cm was 1.02 (95% confidence interval (Cl): 0.96, 1.10) in premenopausal women and 1.07 (95% Cl: 1.03, 1.12) in postmenopausal women. Body mass index (BMI) showed significant inverse and positive associations with breast cancer among pre- and postmenopausal women, respectively; these associations were nonlinear. Compared with premenopausal women with a BMI of less than 21 kg/m2, women with a BMI exceeding 31 kg/m2 had an RR of 0.54 (95% Cl: 0.34, 0.85). In postmenopausal women, the RRs did not increase further when BMI exceeded 28 kg/m2; the RR for these women was 1.26 (95% Cl: 1.09, 1.46). The authors found little evidence for interaction with other breast cancer risk factors. Their data indicate that height is an independent risk factor for postmenopausal breast cancer; in premenopausal women, this relation is less clear. The association between BMI and breast cancer varies by menopausal status. Weight control may reduce the risk among postmenopausal women

    Intake of fruits and vegetables and risk of breast cancer: a pooled analysis of cohort studies.

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    Context: Some epidemiologic studies suggest that elevated fruit and vegetable consumption is associated with a reduced risk of breast cancer. However, most have been case-control studies in which recall and selection bias may influence the results. Additionally, publication bias may have influenced the literature on associations for specific fruit and vegetable subgroups. Objective: To examine the association between breast cancer and total and specific fruit and vegetable group intakes using standardized exposure definitions. Data Sources/Study Selection: Eight prospective studies that had at least 200 incident breast cancer cases, assessed usual dietary intake, and completed a validation study of the diet assessment method or a closely related instrument were included in these analyses. Data Extraction: Using the primary data from each of the studies, we calculated study-specific relative risks (RRs) that were combined using a random-effects model. Data Synthesis: The studies included 7377 incident invasive breast cancer cases occurring among 351825 women whose diet was analyzed at baseline. For comparisons of the highest vs lowest quartiles of intake, weak, nonsignificant associations were observed for total fruits (pooled multivariate RR, 0.93; 95% confidence interval [CI], 0.86-1.00; P for trend = .08), total vegetables (RR, 0.96; 95% CI, 0.89-1.04; P for trend = .54), and total fruits and vegetables (RR, 0.93; 95% CI, 0.86-1.00; P for trend = .12). No additional benefit was apparent in comparisons of the highest and lowest deciles of intake. No associations were observed for green leafy vegetables, 8 botanical groups, and 17 specific fruits and vegetables. Conclusion: These results suggest that fruit and vegetable consumption during adulthood is not significantly associated with reduced breast cancer risk

    The influence of lesion volume, perilesion resection volume, and completeness of resection on seizure outcome after resective epilepsy surgery for cortical dysplasia in children.

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    OBJECT Focal cortical dysplasia (FCD) is one of the most common causes of intractable epilepsy leading to surgery in children. The predictors of seizure freedom after surgical management for FCD are still unclear. The objective of this study was to perform a volumetric analysis of factors shown on the preresection and postresection brain MRI scans of patients who had undergone resective epilepsy surgery for cortical dysplasia and to determine the influence of these factors on seizure outcome. METHODS The authors reviewed the medical records and brain images of 43 consecutive patients with focal MRI-documented abnormalities and a pathological diagnosis of FCD who had undergone surgical treatment for refractory epilepsy. Preoperative lesion volume and postoperative resection volume were calculated by manual segmentation using OsiriX PRO software. RESULTS Forty-three patients underwent first-time surgery for resection of an FCD. The age range of these patients at the time of surgery ranged from 2 months to 21.8 years (mean age 7.3 years). The median duration of follow-up was 20 months. The mean age at onset was 31.6 months (range 1 day to 168 months). Complete resection of the area of an FCD, as adjudged from the postoperative brain MR images, was significantly associated with seizure control (p = 0.0005). The odds of having good seizure control among those who underwent complete resection were about 6 times higher than those among the patients who did not undergo complete resection. Seizure control was not significantly associated with lesion volume (p = 0.46) or perilesion resection volume (p = 0.86). CONCLUSIONS The completeness of FCD resection in children is a significant predictor of seizure freedom. Neither lesion volume nor the further resection of perilesional tissue is predictive of seizure freedom.</jats:sec

    A novel approach to separation of waste printed circuit boards using dimethyl sulfoxide

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    Waste printed circuit boards are complex heterogeneous mixture consisting of organic material, metal and glass fiber, therefore, it is quite difficult for the recovery of valuable materials from waste printed circuit boards. In this study, waste printed circuit boards without electronic components (known as bare boards) are submerged into dimethyl sulfoxide solvent at 170 A degrees C using refluxing process. Metallographic microscope shows that waste printed circuit boards produce the delamination after treated with dimethyl sulfoxide solvent for 15 min. When waste printed circuit boards are treated with dimethyl sulfoxide solvent for 30 min, the separation of waste printed circuit boards is complete to obtain metals and glass fibers. Moreover, the used dimethyl sulfoxide solvent is vaporized by the rotary decompression which obtains regenerative dimethyl sulfoxide and solid residues. Comparing two Fourier transform infrared spectroscopies, it is found that the regenerative dimethyl sulfoxide is the same as original dimethyl sulfoxide. Thermal analyses combined with Fourier transform infrared spectroscopy show that the solid residues are bromine epoxy resins. These findings suggest that this innovative technology offers an environmental friendly process with no pollution and high efficiency for separating valuable materials from waste printed circuit boards.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000313075200019&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Environmental SciencesSCI(E)EI5ARTICLE1175-1801
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