446 research outputs found

    Ultrasonographic (US) findings of digestive system in children with cystic fibrosis

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    Evidence of reduced surface electron-phonon scattering in the conduction band of Bi_{2}Se_{3} by non-equilibrium ARPES

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    The nature of the Dirac quasiparticles in topological insulators calls for a direct investigation of the electron-phonon scattering at the \emph{surface}. By comparing time-resolved ARPES measurements of the TI Bi_{2}Se_{3} with different probing depths we show that the relaxation dynamics of the electronic temperature of the conduction band is much slower at the surface than in the bulk. This observation suggests that surface phonons are less effective in cooling the electron gas in the conduction band.Comment: 5 pages, 3 figure

    A multi-scalar perspective on health and urban housing: an umbrella review

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    With more than half the world’s population living in cities, understanding how the built environment impacts human health at different urban scales is crucial. To be able to shape cities for health, an understanding is needed of planetary health impacts, which encompass the human health impacts of human-caused disruptions on the Earth’s natural ecosystems. This umbrella review maps health evidence across the spatial scales of the built environment (building; neighbourhood; and wider system, including city, regional and planetary levels), with a specific focus on urban housing. Systematic reviews published in English between January 2011 and December 2020 were searched across 20 databases, with 1176 articles identified and 124 articles screened for inclusion. Findings suggests that most evidence reports on health determinants at the neighbourhood level, such as greenspace, physical and socio-economic conditions, transport infrastructure and access to local services. Physical health outcomes are also primarily reported, with an emerging interest in mental health outcomes. There is little evidence on planetary health outcomes and significant gaps in the research literature are identified. Based on these findings, three potential directions are identified for future research

    Mapping the Evolution of Optically-Generated Rotational Wavepackets in a Room Temperature Ensemble of D2_2

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    A coherent superposition of rotational states in D2_2 has been excited by nonresonant ultrafast (12 femtosecond) intense (2 ×\times 1014^{14} Wcm2^{-2}) 800 nm laser pulses leading to impulsive dynamic alignment. Field-free evolution of this rotational wavepacket has been mapped to high temporal resolution by a time-delayed pulse, initiating rapid double ionization, which is highly sensitive to the angle of orientation of the molecular axis with respect to the polarization direction, θ\theta. The detailed fractional revivals of the neutral D2_2 wavepacket as a function of θ\theta and evolution time have been observed and modelled theoretically.Comment: 4 pages, 3 figures. Accepted for publication in Phys. Rev. A. Full reference to follow.

    The Ubiquitin Binding Domain ZnF UBP Recognizes the C-Terminal Diglycine Motif of Unanchored Ubiquitin

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    SummaryUbiquitin binding proteins regulate the stability, function, and/or localization of ubiquitinated proteins. Here we report the crystal structures of the zinc-finger ubiquitin binding domain (ZnF UBP) from the deubiquitinating enzyme isopeptidase T (IsoT, or USP5) alone and in complex with ubiquitin. Unlike other ubiquitin binding domains, this domain contains a deep binding pocket where the C-terminal diglycine motif of ubiquitin is inserted, thus explaining the specificity of IsoT for an unmodified C terminus on the proximal subunit of polyubiquitin. Mutations in the domain demonstrate that it is required for optimal catalytic activation of IsoT. This domain is present in several other protein families, and the ZnF UBP domain from an E3 ligase also requires the C terminus of ubiquitin for binding. These data suggest that binding the ubiquitin C terminus may be necessary for the function of other proteins

    INFECTION WITH PASTEURELLA SPP. IN A NEW ZEALAND RABBIT COLONY

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    ABSTRACT The purpose of the research was to establish the etiology and to fight against the acute respiratory syndrome to New Zealand rabbits, of all ages to which the morbidity and mortality were high, from a farm with intensive breeding. Clinical 760 rabbits were examined, adults, young and new born raised in wire net cages in a closed stable, without draught. The necropsy examination was performed in laboratory on 57 dead rabbits with acute respiratory and also cultivations from trachea, lung, liver and spinal marrow were carried out. We used the bacterioscopic technique, cultivation on usual and selective media for Pasteurella, Mycoplasma and Streptococcus for isolation and identification of the micro-organisms present in the respiratory tract. Out of the 57 examined samples, 28 ones were positive and identified as Pasteurella spp., of which 21 were isolated from trachea, lung and liver and 7 from spinal marrow. Seventeen samples of the 28 examined ones contained both Pasteurella spp. and Mycoplasma spp. and 11 samples Pasteurella spp. and Streptococcus spp. also isolated and identified in trachea and lung. The antibiogram test used bio-discs with penicillin, amoxicillin, gentamicin, spectinomicin, oxytetracycline, erythromycin, enrofloxacin and cefaclor. The rabbits were divided into two groups: the first group was treated with enrofloxacin for 5 days, and the second group was treated with oxytetracycline for 5 days, both administered in drinking water. One day after the beginning of the treatment the rabbits got better and the mortality stopped after the fourth day of treatment

    Possible observation of parametrically amplified coherent phasons in K0.3MoO3 using time-resolved extreme-ultraviolet ARPES

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    We use time- and angle-resolved photoemission spectroscopy (tr-ARPES) in the Extreme Ultraviolet (EUV) to measure the time- and momentum-dependent electronic structure of photo-excited K0.3MoO3. Prompt depletion of the Charge Density Wave (CDW) condensate launches coherent oscillations of the amplitude mode, observed as a 1.7-THz-frequency modulation of the bonding band position. In contrast, the anti-bonding band oscillates at about half this frequency. We attribute these oscillations to coherent excitation of phasons via parametric amplification of phase fluctuations.Comment: 4 figure

    Urinary Malondialdehyde (MDA) Concentrations in the General Population-A Systematic Literature Review and Meta-Analysis.

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    Oxidative stress has been associated with various inflammation-related human diseases. It is defined as an imbalance between the production and elimination of reactive oxygen species (ROS). ROS can oxidize proteins, lipids, and DNA, and some of these oxidized products are excreted in urine, such as malondialdehyde (MDA), which is considered a biomarker for oxidative damage of lipids. To interpret changes of this biomarker as a measure of oxidative species overproduction in humans, a background range for urinary MDA concentration in the general population is needed. We sought to establish urinary MDA concentration ranges for healthy adult populations based on reported values in the available scientific literature. We conducted a systematic review and meta-analysis using the standardized protocol registered in PROSPERO (CRD42020146623). EMBASE, PubMed, Web of Science, and Cochrane library databases were searched from journal inception up to October 2020. We included 35 studies (divided into 47 subgroups for the quantitative analysis). Only studies that measured creatinine-corrected urinary MDA with high-performance liquid chromatography (HPLC) with mass spectrometry (MS), fluorescence detection, or UV photometry were included. The geometric mean (GM) of urinary MDA concentration was 0.10 mg/g creatinine and 95% percentile confidence interval (CI) 0.07-0.12. Age, geographical location but not sex, and smoking status had a significant effect on urinary MDA concentrations. There was a significant increasing trend of urinary MDA concentrations with age. These urinary MDA values should be considered preliminary, as they are based on mostly moderate to some low-quality evidence studies. Although urinary MDA can reliably reflect excessive oxidative stress in a population, the influence of physiological parameters that affect its meaning needs to be addressed as well as harmonizing the chemical analytical methods
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