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Interacting invariants for Floquet phases of fermions in two dimensions
We construct a many-body quantized invariant that sharply distinguishes among two-dimensional nonequilibrium driven phases of interacting fermions. This is an interacting generalization of a band-structure Floquet quasienergy winding number and describes chiral pumping of quantum information along the edge. In particular, our invariant sharply distinguishes between a trivial and anomalous Floquet Anderson insulator in the interacting, many-body localized setting. It also applies more generally to models where only fermion parity is conserved, where it differentiates between trivial models and ones that pump Kitaev Majorana chains to the boundary, such as ones recently introduced in the context of emergent fermions arising from eigenstate Z2 topological order. We evaluate our invariant for the edge of such a system with eigenstate Z2 topological order, and show that it is necessarily nonzero when the Floquet unitary exchanges electric and magnetic excitations, proving a connection between bulk anyonic symmetry and edge chirality that was recently conjectured
Antibiogram and plasmid profiling of carbapenemase and extended spectrum Beta-lactamase (ESBL) producing Escherichia coli and Klebsiella pneumoniae in Abeokuta, South western, Nigeria
Background: The increased reports of ESBL dissemination from various centres in south western, Nigeria and the recent emergence of carbapenem resistant bacteria prompted the conception of this study.Objectives: To demonstrate the relationship between high molecular weight plasmids and the expression of antibiotic multi-resistance including ESBL and carbapenemase.Methods: We investigated 97 isolates of selected organisms consisting of 67 E. coli and 30 Klebseilla spp for the presence of plasmids expressing ESBL including carbapenem-hydrolysing enzymes. Beta-lactamase was determined using acidometric method, while ESBL and carbapenemase activity was determined using the double-disk diffusion test as well as the Modified Hodge test (MHT). Plasmid profiles of ESBL and carbapenemase positive isolates were determined according to standard protocols.Results: An ESBL prevalence rate of 21.6% and carbapenem- resistance rate of 9.3% was recorded. Antibiotic susceptibility profile of ESBL isolates showed 100.0% resistance against Amoxicillin, Cotrimoxazole and Erythromycin. Moderate susceptibility was recorded against the Quinolone class of antibiotics; Meropenem remained the most active antibiotic against ESBL isolates with 62.5% against E. coli and 60% against K. pneumoniae. The plasmid profiles of our study isolates ranged from 11.8kbp to 35.5kbp. Conclusion: Due to the relationship between high molecular weight plasmids and multi-drug resistance, we hereby recommend regular molecular surveillance of this form in our study setting.Keywords: Carbapenem-resistance, ESBL isolates, Plasmid profile, AbeokutaAfrican Health Sciences 2013; 13(4): 1091 - 109
Circulating Plasmodium falciparum and HIV 1/2 as Co-infections among Blood Donors in Ibadan, Southwestern Nigeria
ABSTRACT: Blood serves as a vehicle for transmission of blood-borne pathogens including hemoparasities. In Nigeria, screening of blood for blood-borne pathogens does not fulfill the standard protocols and screening for malaria parasites is not practiced. Determination of the prevalence of circulating Plasmodium falciparum and HIV as co-infections in a population in general, and blood-donors in particular will certainly help in reviewing the screening procedures and making health policy decisions. In view of the problem of transfusional malaria, the prevalence of malaria Plasmodium in consenting blood donors was assessed. Whole blood was used for the diagnosis of P. falciparum malaria using Malaria P. falciparum Rapid Test Device. The screening for HIV antibodies was carried out using Chembio HIV-1/2 Stat-Pak ® and Abbott Determine HIV-1/2 ® test. All tests were done according to the manufacturers' specifications. Overall prevalence rate of asymptomatic P. falciparum malaria was 17.5% (n=35) and HIV as co-infection was 22.9% (n=8), while the remaining 27(77.1%) had no HIV. The study showed no significant difference between malaria infection either for age groups (17.8% vs 16.6%, P>0.05) or sexes (16.6% vs 22.6%, P >0.05). However, it showed a significantly higher prevalence of HIV as co-infection among blood donors within ages less than 40 years than their counterparts in age groups 40 years and above (29.6% vs. 0.0%; P = 0.001). It also showed a significantly higher prevalence of HIV as co-infection among female donors than males (42.9% vs. 17.9%; P = 0.001). This study however confirmed the presence of P. falciparum malaria infection and HIV as co-infection among blood donors in Ibadan, Nigeria. This could be attributed to lack of adequate accommodation and poor sanitary conditions in the area under study. General surveillance and public health education to stop the spread of the infection among blood donors in Ibadan and indeed the whole society is advocated
Imaging Electronic Correlations in Twisted Bilayer Graphene near the Magic Angle
Twisted bilayer graphene with a twist angle of around 1.1{\deg} features a
pair of isolated flat electronic bands and forms a strongly correlated
electronic platform. Here, we use scanning tunneling microscopy to probe local
properties of highly tunable twisted bilayer graphene devices and show that the
flat bands strongly deform when aligned with the Fermi level. At half filling
of the bands, we observe the development of gaps originating from correlated
insulating states. Near charge neutrality, we find a previously unidentified
correlated regime featuring a substantially enhanced flat band splitting that
we describe within a microscopic model predicting a strong tendency towards
nematic ordering. Our results provide insights into symmetry breaking
correlation effects and highlight the importance of electronic interactions for
all filling factors in twisted bilayer graphene.Comment: Main text 9 pages, 4 figures; Supplementary Information 25 page
Significance of Aurora B overexpression in hepatocellular carcinoma. Aurora B Overexpression in HCC
<p>Abstract</p> <p>Background</p> <p>To investigate the significance of Aurora B expression in hepatocellular carcinoma (HCC).</p> <p>Methods</p> <p>The <it>Aurora B </it>and <it>Aurora A </it>mRNA level was measured in 160 HCCs and the paired nontumorous liver tissues by reverse transcription-polymerase chain reaction. Mutations of the <it>p53 </it>and <it>β-catenin </it>genes were analyzed in 134 and 150 tumors, respectively, by direct sequencing of exon 2 to exon 11 of <it>p53 </it>and exon 3 of <it>β-catenin</it>. Anticancer effects of AZD1152-HQPA, an Aurora B kinase selective inhibitor, were examined in Huh-7 and Hep3B cell lines.</p> <p>Results</p> <p><it>Aurora B </it>was overexpressed in 98 (61%) of 160 HCCs and in all 7 HCC cell lines examined. The overexpression of <it>Aurora B </it>was associated with <it>Aurora A </it>overexpression (<it>P </it>= 0.0003) and <it>p53 </it>mutation (<it>P </it>= 0.002) and was inversely associated with <it>β</it>-<it>catenin </it>mutation (<it>P </it>= 0.002). <it>Aurora B </it>overexpression correlated with worse clinicopathologic characteristics. Multivariate analysis confirmed that <it>Aurora B </it>overexpression was an independent poor prognostic factor, despite its interaction with Aurora A overexpression and mutations of <it>p53 </it>and <it>β</it>-<it>catenin</it>. In Huh-7 and Hep3B cells, AZD1152-HQPA induced proliferation blockade, histone H3 (Ser10) dephosphorylation, cell cycle disturbance, and apoptosis.</p> <p>Conclusion</p> <p><it>Aurora B </it>overexpression is an independent molecular marker predicting tumor invasiveness and poor prognosis of HCC. Aurora B kinase selective inhibitors are potential therapeutic agents for HCC treatment.</p
Hypnosis as a treatment of chronic widespread pain in general practice: A randomized controlled pilot trial
<p>Abstract</p> <p>Background</p> <p>Hypnosis treatment in general practice is a rather new concept. This pilot study was performed to evaluate the effect of a standardized hypnosis treatment used in general practice for patients with chronic widespread pain (CWP).</p> <p>Methods</p> <p>The study was designed as a randomized control group-controlled study. Sixteen patients were randomized into a treatment group or a control group, each constituting eight patients. Seven patients in the treatment group completed the schedule. After the control period, five of the patients in the control group also received treatment, making a total of 12 patients having completed the treatment sessions. The intervention group went through a standardized hypnosis treatment with ten consecutive therapeutic sessions once a week, each lasting for about 30 minutes, focusing on ego-strengthening, relaxation, releasing muscular tension and increasing self-efficacy. A questionnaire was developed in order to calibrate the symptoms before and after the 10 weeks period, and the results were interpolated into a scale from 0 to 100, increasing numbers representing increasing suffering. Data were analyzed by means of T-tests.</p> <p>Results</p> <p>The treatment group improved from their symptoms, (change from 62.5 to 55.4), while the control group deteriorated, (change from 37.2 to 45.1), (p = 0,045). The 12 patients who completed the treatment showed a mean improvement from 51.5 to 41.6. (p = 0,046). One year later the corresponding result was 41.3, indicating a persisting improvement.</p> <p>Conclusion</p> <p>The study indicates that hypnosis treatment may have a positive effect on pain and quality of life for patients with chronic muscular pain. Considering the limited number of patients, more studies should be conducted to confirm the results.</p> <p>Trial Registration</p> <p>The study was registered in ClinicalTrials.gov and released 27.08.07 Reg nr NCT00521807 Approval Number: 05032001.</p
Radiation chemistry of solid-state carbohydrates using EMR
We review our research of the past decade towards identification of radiation-induced radicals in solid state sugars and sugar phosphates. Detailed models of the radical structures are obtained by combining EPR and ENDOR experiments with DFT calculations of g and proton HF tensors, with agreement in their anisotropy serving as most important criterion. Symmetry-related and Schonland ambiguities, which may hamper such identification, are reviewed. Thermally induced transformations of initial radiation damage into more stable radicals can also be monitored in the EPR (and ENDOR) experiments and in principle provide information on stable radical formation mechanisms. Thermal annealing experi-ments reveal, however, that radical recombination and/or diamagnetic radiation damage is also quite important. Analysis strategies are illustrated with research on sucrose. Results on dipotassium glucose-1-phosphate and trehalose dihydrate, fructose and sorbose are also briefly discussed. Our study demonstrates that radiation damage is strongly regio-selective and that certain general principles govern the stable radical formation
Neuromuscular training to enhance sensorimotor and functional deficits in subjects with chronic ankle instability: A systematic review and best evidence synthesis
<p>Abstract</p> <p>Objective</p> <p>To summarise the available evidence for the efficacy of neuromuscular training in enhancing sensorimotor and functional deficits in subjects with chronic ankle instability (CAI).</p> <p>Design</p> <p>Systematic review with best evidence synthesis.</p> <p>Data Sources</p> <p>An electronic search was conducted through December 2009, limited to studies published in the English language, using the Pubmed, CINAHL, Embase, and SPORTDiscus databases. Reference screening of all included articles was also undertaken.</p> <p>Methods</p> <p>Studies were selected if the design was a RCT, quasi RCT, or a CCT; the patients were adolescents or adults with confirmed CAI; and one of the treatment options consisted of a neuromuscular training programme. The primary investigator independently assessed the risk of study bias and extracted relevant data. Due to clinical heterogeneity, data was analysed using a best-evidence synthesis.</p> <p>Results</p> <p>Fourteen studies were included in the review. Meta-analysis with statistical pooling of data was not possible, as the studies were considered too heterogeneous. Instead a best evidence synthesis was undertaken. There is limited to moderate evidence to support improvements in dynamic postural stability, and patient perceived functional stability through neuromuscular training in subjects with CAI. There is limited evidence of effectiveness for neuromuscular training for improving static postural stability, active and passive joint position sense (JPS), isometric strength, muscle onset latencies, shank/rearfoot coupling, and a reduction in injury recurrence rates. There is limited evidence of no effectiveness for improvements in muscle fatigue following neuromuscular intervention.</p> <p>Conclusion</p> <p>There is limited to moderate evidence of effectiveness in favour of neuromuscular training for various measures of static and dynamic postural stability, active and passive JPS, isometric strength, muscle onset latencies, shank/rearfoot coupling and injury recurrence rates. Strong evidence of effectiveness was lacking for all outcome measures. All but one of the studies included in the review were deemed to have a high risk of bias, and most studies were lacking sufficient power. Therefore, in future we recommend conducting higher quality RCTs using appropriate outcomes to assess for the effectiveness of neuromuscular training in overcoming sensorimotor deficits in subjects with CAI.</p
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