3,322 research outputs found

    The Single-Photon Router

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    We have embedded an artificial atom, a superconducting "transmon" qubit, in an open transmission line and investigated the strong scattering of incident microwave photons (6\sim6 GHz). When an input coherent state, with an average photon number N1N\ll1 is on resonance with the artificial atom, we observe extinction of up to 90% in the forward propagating field. We use two-tone spectroscopy to study scattering from excited states and we observe electromagnetically induced transparency (EIT). We then use EIT to make a single-photon router, where we can control to what output port an incoming signal is delivered. The maximum on-off ratio is around 90% with a rise and fall time on the order of nanoseconds, consistent with theoretical expectations. The router can easily be extended to have multiple output ports and it can be viewed as a rudimentary quantum node, an important step towards building quantum information networks.Comment: 5 pages, 3 figure

    Plasmodium Falciparum-Induced Kidney and Liver Dysfunction in Malaria Patients in Freetown, Sierra Leone

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    This study was undertaken to investigate the effect of Plasmodium falciparum infection on kidney and liver function parameters in malaria patients in Freetown, Sierra Leone. Blood samples taken from 64 malaria patients and 64 non-malaria volunteers at Abanita and Blue Shield Hospitals, Freetown Sierra Leone between January to April, 2009 were examined. Changes in serum biochemical parameters were analysed using normal range values as baseline. Serum bilirubin, alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) concentrations were significantly elevated in falciparum malaria patients compared to their non-malaria counterparts which is an indication of defective liver function. Most of patients with falciparum malaria also have significantly high serum concentrations of urea, creatinine, sodium and potassium showing alteration in kidney function. This study suggests that malaria parasites could be responsible for derangement of kidney and liver functions in patients and could therefore contribute to organ damage in affected individuals if not treated. Keywords: Kidney function, Liver function, Malaria, Plasmodium falciparu

    Frugivorous bird species diversity in relation to the diversity of fruit tree species in reserved and designated green areas in the federal capital territory, Nigeria

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    The diversity of frugivorous bird species in relation to tree species diversity was investigated in Designated and Reserved Green Areas of Abuja, Nigeria. The study estimated, investigated and examined trees species and avian frugivore in terms of their diversity. Point-Centered Quarter Method (PCQM) was used for vegetation analysis while random walk and focal observation was used for bird frugivore identification and enumeration. data was collected from six locations coinciding with the local administrative areas within the Federal Capital Territory. These were, the Abuja Municipal Area Council (AMAC), Abaji, Bwari, Gwagwalada, Kuje and Kwali. AMAC is designated as urban while the remaining five sites are designated as sub-urban. The highest number of fruit tree species was encountered in AMAC (30), followed by Abaji (29) while 27, 25, 19 and 11 fruit tree species were encountered in Kwali, Bwari Gwagwalada and Kuje respectively. The similarity or otherwise dissimilarity in fruit tree species composition between each pair of the enumerated sites showed Gwagwalada and Kuje as the most similar, and the similarity or otherwise dissimilarity in frugivorous bird species composition between each pair of the enumerated showed higher species similarity between the AMAC and each of the other sites, and between each pair of the sites than that of the fruit trees in the respective sites. Highest number of frugivore bird species was encountered in Kwali (41), followed by Bwari (39) and AMAC (38) while 35, 34 and 21 species were encountered in Gwagwalada, Kuje and Abaji respectively. The alpha (within-site) diversity of frugivore bird species at different sites using Simpson and Shannon-Wiener diversity indices showed that Gwagwalada is the most diverse of all the sites, followed by Kuje and Kwali respectively. The diversity indices of frugivores and fruit-trees were correlated, a weak relationship was observed (r= - 0.2323 and r = - 0.1626), and Null hypothesis was accepted. Also, ANOVA was carried out to test for significance between the sites and the tree physical structure parameters. The result showed no significant difference between the sites (Fcal=0.236603 and F Crit =2.901295), and the null hypotheses was accepted. Again, there was significant differences between the tree physical structure parameters (Fcal=20.58803 and F Crit =3.287382), the null hypothesis was rejected. It was therefore concluded that these reserved areas need more protection to enhance both the beta and alpha diversities in order to support more interactions.Keywords: Frugivores, Fruit trees, Diversity, Interaction, Green Areas, Urban ecosystem

    Occurrence of Pospiviroid in potato, tomato and some ornamental plants in Turkey

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    In order to investigate the Pospiviroid in potato, tomato and some ornamental plants in Turkey, a survey study was carried out from 2006 to 2009. During this survey study, a total of 1766 samples (1047potato samples, 258 tomato leaves and 461 ornamental plants) were tested by reverse transcriptionpolymerase chain reaction (RT-PCR) and, the samples found to be positive in RT-PCR were also checked in return polyacrylamide gel electrophoresis (R-PAGE). Of these samples, potato tubers were collected from markets, leaf samples from potato fields (Erzurum), tomato samples from field (Tokat, Amasya, Balýkesir and Bursa) and greenhouses (Antalya and Mula), leaves and vines of ornamental plants from greenhouses (Yalova) and florists (Erzurum) and recreation areas (Ankara, zmir and Trabzon). In the result of RT-PCR test, PSTVd was detected in 6 out of 891 potato tubers and CSVd in 2out of 154 chrysanthemums. On the other side, tomato, citrus and most ornamental plants belonging to different families were found to be free from pospiviroid. This is the first report of CSVd in Turkey

    Transcranial Direct-Current Stimulation May Improve Discourse Production in Healthy Older Adults

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    Background: The use of transcranial direct-current stimulation (tDCS) for therapeutic and neurorehabilitation purposes has become increasingly popular in recent years. Previous research has found that anodal tDCS may enhance naming ability and verbal fluency in healthy participants. However, the effect of tDCS on more functional, higher level language skills such as discourse production has yet to be understood. Aims: The present study aimed to investigate in healthy, older adults (a) the effect of anodal tDCS on discourse production vs. sham stimulation and (b) optimal electrode placement for tDCS to target language improvement at the discourse level. / Methods: Fourteen healthy, older right-handed participants took part in this sham controlled, repeated measures pilot study. Each participant experienced three different experimental conditions; anodal tDCS on the left inferior frontal gyrus (IFG), anodal tDCS on the right IFG and sham stimulation while performing a story telling task. Significant changes in language performance before and after each condition were examined in three discourse production tasks: recount, procedural and narrative. / Results: Left and right IFG conditions showed a greater number of significant within-group improvements (p < 0.05) in discourse production compared to sham with 6/12 for left IFG, 4/12 for right IFG and 2/12 for sham. There were no significant differences noted between tDCS conditions. No relationship was noted between language performance and physical activity, age, or gender. / Conclusions: This study suggests that anodal tDCS may significantly improve discourse production in healthy, older adults. In line with previous tDCS language studies, the left IFG is highlighted as an optimal stimulation site for the modulation of language in healthy speakers. The findings support further exploration of tDCS as a rehabilitative tool for higher-level language skills in persons with aphasia

    Socio-ecological survey of parks and gardens in the federal capital territory, Abuja Nigeria

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    Opinions of Abuja residents and potential recreational parks and gardens users were sought using structured questionnaires in order to document their socio-ecological knowledge. Three hundred (300) respondents were randomly selected from each of the Area Councils and questioned on the following socio-ecological issues: satisfaction with parks in the FCT, satisfaction with recreational facilities in the FCT, major activities in city parks and the recreational facilities, activities respondents want to see in parks, assessment on the amount of greening, security in parks, reasons for not using parks, willingness to pay for re-vegetation, participation in parks community services and awareness of publications by department of parks. The results showed that majority of the respondents (79%) and (70%) were not satisfied with the number of Parks in the FCT and Recreational Facilities in the FCT respectively. Also, on the major kinds of activity people would like to in City Parks and Recreational Facilities, selling of drinks (bar operation) was the highest (26%). On the facilities which respondents want to see in Parks highest number of respondents 31% would like Community centers. The amount of Greening was also assessed, majority of the respondents (83%) were not satisfied with the amount of greening in the FCT. On the Provision of Security in the Parks, majority of the respondents (84.3%) were not satisfied. Furthermore, reasons why some people may not like to use the parks were investigated, and three major reasons advanced were rowdy atmosphere, religious consideration and family background. Highest number of respondents 40.7% observed that rowdy atmosphere hindered them from patronizing the parks. On the willingness of people to pay for re-vegetation, 52% of the respondents were willing to pay for revegetation in the Council Areas. Again, participation in Parks Community Services was high, and concerning the Awareness of Publications by Department of Parks, 81% respondents were aware of the publications by department of parks in the Council Areas. These parks and green areas are the ecological units with indicators that need urgent policies for their maintenance and sustenance for both ecological and socio-ecological benefits.Keywords: Urban ecosystem, Natural ecosystem, Green Area, Recreational Parks, Gardens, Ecolog

    Giant Cross Kerr Effect for Propagating Microwaves Induced by an Artificial Atom

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    We have investigated the cross Kerr phase shift of propagating microwave fields strongly coupled to an artificial atom. The artificial atom is a superconducting transmon qubit in an open transmission line. We demonstrate average phase shifts of 11 degrees per photon between two coherent microwave fields both at the single-photon level. At high control power, we observe phase shifts up to 30 degrees. Our results provide an important step towards quantum gates with propagating photons in the microwave regime.Comment: 5 pages, 4 figure

    Assessment of healthcare delivery in the early management of bacterial meningitis in UK young infants: an observational study.

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    OBJECTIVE: To define early presenting features of bacterial meningitis in young infants in England and to review the adequacy of individual case management as compared with relevant national guidelines and an expert panel review. DESIGN: Retrospective medical case note review and parental recall using standardised questionnaires. SETTING: England and Wales. PARTICIPANTS: Infants aged <90 days with bacterial meningitis diagnosed between July 2010 and July 2013. RESULTS: Of the 97 cases recruited across England and Wales, 66 (68%) were admitted from home and 31 (32%) were in hospital prior to disease onset. Almost all symptoms reported by parents appeared at the onset of the illness, with very few new symptoms appearing subsequently. Overall, 20/66 (30%) infants were assessed to have received inappropriate prehospital management. The median time from onset of first symptoms to first help was 5 hours (IQR: 2-12) and from triage to receipt of first antibiotic dose was 2.0 hours (IQR: 1.0-3.3), significantly shorter in infants with fever or seizures at presentation compared with those without (1.7 (IQR: 1.0-3.0) vs 4.2 (IQR: 1.8-6.3) hours, p=0.02). Overall, 26 (39%) infants had a poor outcome in terms of death or neurological complication; seizures at presentation was the only significant independent risk factor (OR, 7.9; 95% CI 2.3 to 207.0). For cases in hospital already, the median time from onset to first dose of antibiotics was 2.6 (IQR: 1.3-9.8) hours, and 12/31 (39%) of infants had serious neurological sequelae at hospital discharge. Hearing test was not performed in 23% and when performed delayed by ≥4 weeks in 41%. CONCLUSIONS: In young infants, the non-specific features associated with bacterial meningitis appear to show no progression from onset to admission, whereas there were small but significant differences in the proportion of infants with more specific symptoms at hospital admission compared with at the onset of the illness, highlighting the difficulties in early recognition by parents and healthcare professionals alike. A substantial proportion of infants received inappropriate prehospital and posthospital management. We propose a targeted campaign for education and harmonisation of practice with evidence-based management algorithms
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