Spatiotemporal chaos induces extreme events in an extended microcavity laser

Extreme events such as rogue wave in optics and fluids are often associated with the merging dynamics of coherent structures. We present experimental and numerical results on the physics of extreme events appearance in a spatially extended semiconductor microcavity laser with intracavity saturable absorber. This system can display deterministic irregular dynamics only thanks to spatial coupling through diffraction of light. We have identified parameter regions where extreme events are encountered and established the origin of this dynamics in the emergence of deterministic spatiotemporal chaos, through the correspondence between the proportion of extreme events and the dimension of the strange attractor

Are estimates of socioeconomic inequalities in chronic disease artefactually narrowed by self-reported measures of prevalence in low-income and middle-income countries? Findings from the WHO-SAGE survey

Background: The use of self-reported measures of chronic disease may substantially underestimate prevalence in low-income and middle-income country settings, especially in groups with lower socioeconomic status (SES). We sought to determine whether socioeconomic inequalities in the prevalence of non-communicable chronic diseases (NCDs) differ if estimated by using symptom-based or criterion-based measures compared with self-reported physician diagnoses. Methods: Using population-representative data sets of the WHO Study of Global Ageing and Adult Health (SAGE), 2007–2010 (n=42 464), we calculated wealth-related and education-related concentration indices of self-reported diagnoses and symptom-based measures of angina, hypertension, asthma/chronic lung disease, visual impairment and depression in three ‘low-income and lower middle-income countries’—China, Ghana and India—and three ‘upper-middle-income countries’—Mexico, Russia and South Africa. Results: SES gradients in NCD prevalence tended to be positive for self-reported diagnoses compared with symptom-based/criterion-based measures. In China, Ghana and India, SES gradients were positive for hypertension, angina, visual impairment and depression when using self-reported diagnoses, but were attenuated or became negative when using symptom-based/criterion-based measures. In Mexico, Russia and South Africa, this distinction was not observed consistently. For example, concentration index of self-reported versus symptom-based angina were: in China: 0.07 vs −0.11, Ghana: 0.04 vs −0.21, India: 0.02 vs −0.16, Mexico: 0.19 vs −0.22, Russia: −0.01 vs −0.02 and South Africa: 0.37 vs 0.02. Conclusions: Socioeconomic inequalities in NCD prevalence tend to be artefactually positive when using self-report compared with symptom-based or criterion-based diagnostic criteria, with greater bias occurring in low-income countries. Using standardised, symptom-based measures would provide more valid estimates of NCD inequalities

Extraction and characterization of chitin and chitosan from crustacean by-products: Biological and physicochemical properties

Chitin has been extracted from two Tunisian crustacean species. The obtained chitin was transformed into the more useful soluble chitosan. These products were characterized by their biological activity as antimicrobial and antifungal properties. The tested bacterial strains were Escherichia coli American Type Cell Culture (ATCC) 25922, Pseudomonas aeruginosa ATCC 27950 and Staphylococcus aureus ATCC 25923. Four fungi strains were also tested Candida glabrata, Candida albicans, Candidaparapsilensis and Candida kreusei. Squilla chitosan showed a minimum inhibitory concentration (MIC) against the different fungi exceptionally for C. kreusei. Their antioxidant activity was investigated with 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and inhibition of linoleic acid peroxidation. Parapenaeus longirostris Chitosan showed the highest radical scavenging properties. Chitin and chitosan produced were also characterized with Fourier Transform Infrared Spectroscopy (FTIR).Key words: Antibacterial, antifungal, antioxidant, chitin, chitosan, crustacean

Osteite frontale post-sinusitique: Etude rétrospective à propos de 31 cas

Objective : Post-sinusitic frontal osteitis is defined as an extension of frontal sinus infection to the adjacent bony structures. It is an emergency that should rapidly be diagnosed and treated. The aim of this study is to analyze epidemiologic, clinical and paraclinical features, and to review different therapeutic modalities of this disease.Materials and methods : We carry a retrospective study about 31 patients diagnosed and treated between 1996 and 2010. All patients underwent complete ENT and neurological examination, biological investigations, sino-nasal and cerebral CT scan. Antibiotherapy was administrated intravenously. Surgical drainage of the frontal sinus was performed eitherby trephination, by osteoplastic flap confection, or by Lemoyne drain placement. Endonasal drainage consisted of middle meatotomy with anterior ethmoidectomy. Frontal sinus cranialisation was performed with coronal approach. Evolution was assessed on clinical, biological and radiological criteria.Results : Mean age was 24,4 years (8-62 years) and sex-ratio 4,16. Frontal headache (10 cases) and intracranial hypertension signs (8 cases) were the most frequent functional symptoms. Frontal tumefaction was noted in 9 patients, associated in 5 cases with orbital tumefaction of the internal eye angle. Rhinological signs were essentially purulent rhinorrhea(9 cases) and nasal obstruction (5 cases). Nasal endoscopy showed purulent secretions at themiddlemeatus in 12 cases. CT scan revealed a typical aspect of frontal osteitis with bony lysis. A sub-periostal abscess was associated in 7 patients. Intracranial extension was noted in 15 cases and orbital extension in 7 cases. Bacteriological examination was positivein 8 cases. Most frequent bacteria were streptococcus and staphylococcus aureus (3 cases each). Antibiotic therapy was initially administrated in all cases. Concerning initial surgical treatment, 9 patients underwent frontaldrainage and 2 others orbital drainage. On the other hand, 4 patients underwent only sub-periostal abscess drainage. This one was associated with cranialisation in another case. For patients having endocranial complications, empyema drainage was realized in 14 cases, associed in 6 of them with cranialisation. Cerebral abscess drainage was performedin one other patient. Clinical and radiological evolution was favourable in 24 patients (77,4%). The seven other patients were reoperated because of persistence or aggravation of clinical symptoms. Later evolution was favourable.Conclusion : Post-sinusitic frontal osteitis a rare and serious affection. Diagnosis, based on clinical and radiological features, should be early made. Adequate treatment have to be instituted to prevent life-threatening complications.Keywords : osteitis, frontal sinus, sinusitis, computed tomography, drainage, cranialisatio

Utilization of a deoxynucleoside diphosphate substrate by HIV reverse transcriptase

Background: Deoxynucleoside triphosphates (dNTPs) are the normal substrates for DNA sysnthesis is catalyzed by polymerases such as HIV-1 reverse transcriptase (RT). However, substantial amounts of deoxynucleoside diphosphates (dNDPs) are also present in the cell. Use of dNDPs in HIV-1 DNA sysnthesis could have significant implications for the efficacy of nucleoside RT inhibitors such as AZT which are first line therapeutics fro treatment of HIV infection. Our earlier work on HIV-1 reverse transcriptase (RT) suggested that the interaction between the γ phosphate of the incoming dNTP and RT residue K65 in the active site is not essential for dNTP insertion, implying that this polymerase may be able to insert dNPs in addition to dNTPs. Methodology/Principal Findings: We examined the ability of recombinant wild type (wt) and mutant RTs with substitutions at residue K65 to utilize a dNDP substrate in primer extension reactions. We found that wild type HIV-1 RT indeed catalyzes incorporation of dNDP substrates whereas RT with mutations of residue K645 were unable to catalyze this reaction. Wild type HIV-1 RT also catalyzed the reverse reaction, inorganic phosphate-dependent phosphorolysis. Nucleotide-mediated phosphorolytic removal of chain-terminating 3′-terminal nucleoside inhibitors such as AZT forms the basis of HIV-1 resistance to such drugs, and this removal is enhanced by thymidine analog mutations (TAMs). We found that both wt and TAM-containing RTs were able to catalyze Pi-mediated phosphorolysis of 3′-terminal AZT at physiological levels of Pi with an efficacy similar to that for ATP-dependent AZT-excision. Conclusion: We have identified two new catalytic function of HIV-1 RT, the use of dNDPs as substrates for DNA synthesis, and the use of Pi as substrate for phosphorolytic removal of primer 3′-terminal nucleotides. The ability to insert dNDPs has been documented for only one other DNA polymerase The RB69 DNA polymerase and the reverse reaction employing inorganic phosphate has not been documented for any DNA polymerase. Importantly, our results show that Pi-mediated phosphorolysis can contribute to AZT resistance and indicates that factors that influence HIV resistance to AZT are more complex than previously appreciated. © 2008 Garforth et al

Research for food and health in Europe: themes, needs and proposals

Background Diet, in addition to tobacco, alcohol and physical exercise, is a major factor contributing to chronic diseases in Europe. There is a pressing need for multidisciplinary research to promote healthier food choices and better diets. Food and Health Research in Europe (FAHRE) is a collaborative project commissioned by the European Union. Among its tasks is the description of national research systems for food and health and, in work reported here, the identification of strengths and gaps in the European research base. Methods A typology of nine research themes was developed, spanning food, society, health and research structures. Experts were selected through the FAHRE partners, with balance for individual characteristics, and reported using a standardised template. Results Countries usually commission research on food, and on health, separately: few countries have combined research strategies or programmes. Food and health are also strongly independent fields within the European Commission's research programmes. Research programmes have supported food and bio-technology, food safety, epidemiological research, and nutritional surveillance; but there has been less research into personal behaviour and very little on environmental influences on food choices - in the retail and marketing industries, policy, and regulation. The research is mainly sited within universities and research institutes: there is relatively little published research contribution from industry. Discussion National food policies, based on epidemiological evidence and endorsed by the World Health Organisation, recommend major changes in food intake to meet the challenge of chronic diseases. Biomedical and biotechnology research, in areas such as 'nutrio-genomics', 'individualised' diets, 'functional' foods and 'nutri-pharmaceuticals' appear likely to yield less health benefit, and less return on public investment, than research on population-level interventions to influence dietary patterns: for example policies to reduce population consumption of trans fats, saturated fats, salt and energy density. Research should now address how macro-diets, rather than micro-nutritional content, can be improved for beneficial impacts on health, and should evaluate the impact of market changes and policy interventions, including regulation, to improve public health. Conclusions European and national research on food and health should have social as well as commercial benefits. Strategies and policies should be developed between ministries of health and national research funding agencies. Collaboration between member states in the European Union can yield better innovation and greater competitive advantage

Multi-resolution anisotropy studies of ultrahigh-energy cosmic rays detected at the Pierre Auger Observatory

We report a multi-resolution search for anisotropies in the arrival directions of cosmic rays detected at the Pierre Auger Observatory with local zenith angles up to $80^\circ$ and energies in excess of 4 EeV ($4 \times 10^{18}$ eV). This search is conducted by measuring the angular power spectrum and performing a needlet wavelet analysis in two independent energy ranges. Both analyses are complementary since the angular power spectrum achieves a better performance in identifying large-scale patterns while the needlet wavelet analysis, considering the parameters used in this work, presents a higher efficiency in detecting smaller-scale anisotropies, potentially providing directional information on any observed anisotropies. No deviation from isotropy is observed on any angular scale in the energy range between 4 and 8 EeV. Above 8 EeV, an indication for a dipole moment is captured; while no other deviation from isotropy is observed for moments beyond the dipole one. The corresponding $p$-values obtained after accounting for searches blindly performed at several angular scales, are $1.3 \times 10^{-5}$ in the case of the angular power spectrum, and $2.5 \times 10^{-3}$ in the case of the needlet analysis. While these results are consistent with previous reports making use of the same data set, they provide extensions of the previous works through the thorough scans of the angular scales.Comment: Published version. Added journal reference and DOI. Added Report Numbe

Ultrahigh-energy neutrino follow-up of Gravitational Wave events GW150914 and GW151226 with the Pierre Auger Observatory

On September 14, 2015 the Advanced LIGO detectors observed their first gravitational-wave (GW) transient GW150914. This was followed by a second GW event observed on December 26, 2015. Both events were inferred to have arisen from the merger of black holes in binary systems. Such a system may emit neutrinos if there are magnetic fields and disk debris remaining from the formation of the two black holes. With the surface detector array of the Pierre Auger Observatory we can search for neutrinos with energy above 100 PeV from point-like sources across the sky with equatorial declination from about -65 deg. to +60 deg., and in particular from a fraction of the 90% confidence-level (CL) inferred positions in the sky of GW150914 and GW151226. A targeted search for highly-inclined extensive air showers, produced either by interactions of downward-going neutrinos of all flavors in the atmosphere or by the decays of tau leptons originating from tau-neutrino interactions in the Earth's crust (Earth-skimming neutrinos), yielded no candidates in the Auger data collected within $\pm 500$ s around or 1 day after the coordinated universal time (UTC) of GW150914 and GW151226, as well as in the same search periods relative to the UTC time of the GW candidate event LVT151012. From the non-observation we constrain the amount of energy radiated in ultrahigh-energy neutrinos from such remarkable events.Comment: Published version. Added journal reference and DOI. Added Report Numbe