4,635 research outputs found

    Radio meteorology at jpl goldstone pioneer station, july 14, 1965 final report

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    Macroscopic refractive index structure of troposphere and local microscopic refractive index variations - radio meteorolog

    ADRIC: Adverse Drug Reactions In Children - a programme of research using mixed methods

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    Aims To comprehensively investigate the incidence, nature and risk factors of adverse drug reactions (ADRs) in a hospital-based population of children, with rigorous assessment of causality, severity and avoidability, and to assess the consequent impact on children and families. We aimed to improve the assessment of ADRs by development of new tools to assess causality and avoidability, and to minimise the impact on families by developing better strategies for communication. Review methods Two prospective observational studies, each over 1 year, were conducted to assess ADRs in children associated with admission to hospital, and those occurring in children who were in hospital for longer than 48 hours. We conducted a comprehensive systematic review of ADRs in children. We used the findings from these studies to develop and validate tools to assess causality and avoidability of ADRs, and conducted interviews with parents and children who had experienced ADRs, using these findings to develop a leaflet for parents to inform a communication strategy about ADRs. Results The estimated incidence of ADRs detected in children on admission to hospital was 2.9% [95% confidence interval (CI) 2.5% to 3.3%]. Of the reactions, 22.1% (95% CI 17% to 28%) were either definitely or possibly avoidable. Prescriptions originating in the community accounted for 44 out of 249 (17.7%) of ADRs, the remainder originating from hospital. A total of 120 out of 249 (48.2%) reactions resulted from treatment for malignancies. Off-label and/or unlicensed (OLUL) medicines were more likely to be implicated in an ADR than authorised medicines [relative risk (RR) 1.67, 95% CI 1.38 to 2.02; p  48 hours, the overall incidence of definite and probable ADRs based on all admissions was 15.9% (95% CI 15.0 to 16.8). Opiate analgesic drugs and drugs used in general anaesthesia (GA) accounted for > 50% of all drugs implicated in ADRs. The odds ratio of an OLUL drug being implicated in an ADR compared with an authorised drug was 2.25 (95% CI 1.95 to 2.59; p < 0.001). Risk factors identified were exposure to a GA, age, oncology treatment and number of medicines. The systematic review estimated that the incidence rates for ADRs causing hospital admission ranged from 0.4% to 10.3% of all children [pooled estimate of 2.9% (95% CI 2.6% to 3.1%)] and from 0.6% to 16.8% of all children exposed to a drug during hospital stay. New tools to assess causality and avoidability of ADRs have been developed and validated. Many parents described being dissatisfied with clinician communication about ADRs, whereas parents of children with cancer emphasised confidence in clinician management of ADRs and the way clinicians communicated about medicines. The accounts of children and young people largely reflected parents’ accounts. Clinicians described using all of the features of communication that parents wanted to see, but made active decisions about when and what to communicate to families about suspected ADRs, which meant that communication may not always match families’ needs and expectations. We developed a leaflet to assist clinicians in communicating ADRs to parents. Conclusion The Adverse Drug Reactions In Children (ADRIC) programme has provided the most comprehensive assessment, to date, of the size and nature of ADRs in children presenting to, and cared for in, hospital, and the outputs that have resulted will improve the management and understanding of ADRs in children and adults within the NHS. Recommendations for future research: assess the values that parents and children place on the use of different medicines and the risks that they will find acceptable within these contexts; focusing on high-risk drugs identified in ADRIC, determine the optimum drug dose for children through the development of a gold standard practice for the extrapolation of adult drug doses, alongside targeted pharmacokinetic/pharmacodynamic studies; assess the research and clinical applications of the Liverpool Causality Assessment Tool and the Liverpool Avoidability Assessment Tool; evaluate, in more detail, morbidities associated with anaesthesia and surgery in children, including follow-up in the community and in the home setting and an assessment of the most appropriate treatment regimens to prevent pain, vomiting and other postoperative complications; further evaluate strategies for communication with families, children and young people about ADRs; and quantify ADRs in other settings, for example critical care and neonatology

    Sistema Bragantino: modelo de agricultura em bases sustentáveis no Pará.

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    O sistema de agricultura utilizado no nordeste do Pará sempre foi o de derruba-e-queima que já dizimou a floresta primária antes existente. A atividade agrícola é exercida, por pequenos produtores com culturas anuais, sem calcário e fertilizantes, esgotando os nutrientes dos solos. Neste trabalho, o Sistema Bragantino foi testado para substituir o atual modelo utilizado, sendo instaladas nove UD's na região. Foram usados o milho, a mandioca e feijão-caupi, em rotação e consórcio. A adubação de fundação aumentou o P, Ca e Mg e diminuiu o Al e sua saturação no solo. As produtividades de milho e mandioca aumentaram e do caupi se manteve próximo da média regional. O rendimento médio da mandioca nas UD's foi 226,7% maior que a produtividade média do Estado do Pará. O Sistema Bragantino apresenta ainda outras vantagens, tais como: restaura a fertilidade do solo e possibilita o uso de áreas degradadas; elimina o uso do fogo e contribui para a preservação ambiental; permite o cultivo de até três culturas/ano, na mesma área, diminuindo os risco da atividade agrícola; aumenta a produtividade das culturas; aumenta a renda e melhora a qualidade de vida no campo; diminui os risco de erosão e de assoreamento dos cursos d?água, dentre outras

    Sistema Bragantino: agricultura sustentável para a Amazônia.

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    Caracterização da região e dos sistemas de produção em uso. Sistema Bragantino. Considerações sobre as alternativas de rotação e consórcios. Etapas do trabalho. Sugestões de adubação e calagem para as culturas. Coeficientes técnicos.bitstream/item/25752/1/Doc218.pdfDisponível também on-line. 2ª impressão: 2009

    Binomial coefficients, Catalan numbers and Lucas quotients

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    Let pp be an odd prime and let a,ma,m be integers with a>0a>0 and m≢0(modp)m \not\equiv0\pmod p. In this paper we determine k=0pa1(2kk+d)/mk\sum_{k=0}^{p^a-1}\binom{2k}{k+d}/m^k mod p2p^2 for d=0,1d=0,1; for example, k=0pa1(2kk)mk(m24mpa)+(m24mpa1)up(m24mp)(modp2),\sum_{k=0}^{p^a-1}\frac{\binom{2k}k}{m^k}\equiv\left(\frac{m^2-4m}{p^a}\right)+\left(\frac{m^2-4m}{p^{a-1}}\right)u_{p-(\frac{m^2-4m}{p})}\pmod{p^2}, where ()(-) is the Jacobi symbol, and {un}n0\{u_n\}_{n\geqslant0} is the Lucas sequence given by u0=0u_0=0, u1=1u_1=1 and un+1=(m2)unun1u_{n+1}=(m-2)u_n-u_{n-1} for n=1,2,3,n=1,2,3,\ldots. As an application, we determine 0<k<pa,kr(modp1)Ck\sum_{0<k<p^a,\, k\equiv r\pmod{p-1}}C_k modulo p2p^2 for any integer rr, where CkC_k denotes the Catalan number (2kk)/(k+1)\binom{2k}k/(k+1). We also pose some related conjectures.Comment: 24 pages. Correct few typo

    Two-Level Atom in an Optical Parametric Oscillator: Spectra of Transmitted and Fluorescent Fields in the Weak Driving Field Limit

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    We consider the interaction of a two-level atom inside an optical parametric oscillator. In the weak driving field limit, we essentially have an atom-cavity system driven by the occasional pair of correlated photons, or weakly squeezed light. We find that we may have holes, or dips, in the spectrum of the fluorescent and transmitted light. This occurs even in the strong-coupling limit when we find holes in the vacuum-Rabi doublet. Also, spectra with a sub-natural linewidth may occur. These effects disappear for larger driving fields, unlike the spectral narrowing obtained in resonance fluorescence in a squeezed vacuum; here it is important that the squeezing parameter NN tends to zero so that the system interacts with only one correlated pair of photons at a time. We show that a previous explanation for spectral narrowing and spectral holes for incoherent scattering is not applicable in the present case, and propose a new explanation. We attribute these anomalous effects to quantum interference in the two-photon scattering of the system.Comment: 10 pages, 17 figures, submitted to Phys Rev

    Utilizing Online Social Network and Location-Based Data to Recommend Products and Categories in Online Marketplaces

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    Recent research has unveiled the importance of online social networks for improving the quality of recommender systems and encouraged the research community to investigate better ways of exploiting the social information for recommendations. To contribute to this sparse field of research, in this paper we exploit users' interactions along three data sources (marketplace, social network and location-based) to assess their performance in a barely studied domain: recommending products and domains of interests (i.e., product categories) to people in an online marketplace environment. To that end we defined sets of content- and network-based user similarity features for each data source and studied them isolated using an user-based Collaborative Filtering (CF) approach and in combination via a hybrid recommender algorithm, to assess which one provides the best recommendation performance. Interestingly, in our experiments conducted on a rich dataset collected from SecondLife, a popular online virtual world, we found that recommenders relying on user similarity features obtained from the social network data clearly yielded the best results in terms of accuracy in case of predicting products, whereas the features obtained from the marketplace and location-based data sources also obtained very good results in case of predicting categories. This finding indicates that all three types of data sources are important and should be taken into account depending on the level of specialization of the recommendation task.Comment: 20 pages book chapte
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