849 research outputs found

    The influence of sighing respirations on infant lung function measured using multiple breath washout gas mixing techniques

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    There is substantial interest in studying lung function in infants, to better understand the early life origins of chronic lung diseases such as asthma. Multiple breath washout (MBW) is a technique for measuring lung function that has been adapted for use in infants. Respiratory sighs occur frequently in young infants during natural sleep, and in accordance with current MBW guidelines, result in exclusion of data from a substantial proportion of testing cycles. We assessed how sighs during MBW influenced the measurements obtained using data from 767 tests conducted on 246 infants (50% male; mean age 43 days) as part of a large cohort study. Sighs occurred in 119 (15%) tests. Sighs during the main part of the wash‐in phase (before the last 5 breaths) were not associated with differences in standard MBW measurements compared with tests without sighs. In contrast, sighs that occurred during the washout were associated with a small but discernible increase in magnitude and variability. For example, the mean lung clearance index increased by 0.36 (95% CI: 0.11–0.62) and variance increased by a multiplicative factor of 2 (95% CI: 1.6–2.5). The results suggest it is reasonable to include MBW data from testing cycles where a sigh occurs during the wash‐in phase, but not during washout, of MBW. By recovering data that would otherwise have been excluded, we estimate a boost of about 10% to the final number of acceptable tests and 6% to the number of individuals successfully tested

    Molecular basis of human carbonic anhydrase II deficiency.

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    Effect of egg turning and incubation time on carbonic anhydrase gene expression in the blastoderm of the Japanese quail (Coturnix c. japonica)

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    (1) The gene expression of carbonic anhydrase, a key enzyme for the production sub-embryonic fluid (SEF), was assessed in turned and unturned eggs of the Japanese quail. The plasma membrane-associated isoforms CA IV, CAIX, CA XII, CA XIV, and the cytoplasmic isoform CA II, were investigated in the extra-embryonic tissue of the blastoderm and in embryonic blood. (2) Eggs were incubated at 37.6C, c. 60% R.H., and turned hourly (90 ) or left unturned. From 48 to 96 hours of incubation mRNA was extracted from blastoderm tissue, reverse-transcribed to cDNA and quantified by real-time qPCR using gene-specific primers. Blood collected at 96h was processed identically. (3) Blastoderm CAIV gene expression increased with the period of incubation only in turned eggs, with maxima at 84 and 96h of incubation. Only very low levels were found in blood. (4) Blastoderm CA II gene expression was greatest at 48 and 54h of incubation, subsequently declining to much lower levels and una ected by turning. Blood CA II gene expression was about 25-fold greater than that in the blastoderm. (5) The expression of CA IX in the blastoderm was the highest of all isoforms, yet unaffected by turning. CA XII did not amplify and CA XIV was present at unquantifiable low levels. (6) It is concluded that solely gene expression for CA IV is sensitive to egg turning, and that increased CA IV gene expression could account for the additional SEF mass found at 84-96h of incubation. in embryos of turned eggs

    Respiratory impedance in healthy unsedated South African infants: Effects of maternal smoking

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    Background and objective: Non-invasive techniques for measuring lung mechanics in infants are needed for a better understanding of lung growth and function, and to study the effects of prenatal factors on subsequent lung growth in healthy infants. The forced oscillation technique requires minimal cooperation from the individual but has rarely been used in infants. The study aims to assess the use of the forced oscillation technique to measure the influence of antenatal exposures on respiratory mechanics in unsedated infants enrolled in a birth cohort study in Cape Town, South Africa. Methods: Healthy term infants were studied at 6–10 weeks of age using the forced oscillation technique. Respiratory impedance was measured in the frequency range 8–48 Hz via a face mask during natural sleep. Respiratory system resistance, compliance and inertance were calculated from the impedance spectra. Results: Of 177 infants tested, successful measurements were obtained in 164 (93%). Median (25–75%) values for resistance, compliance and inertance were 50.2 (39.5–60.6) cmH2O.s.L−1, 0.78 (0.61–0.99) mL.cmH2O−1 and 0.062 (0.050–0.086) cmH2O.s2.L−1, respectively. As a group, male infants had 16% higher resistance (P = 0.006) and 18% lower compliance (P  = 0.02) than females. Infants whose mothers smoked during pregnancy had a 19% lower compliance than infants not exposed to tobacco smoke during pregnancy (P = 0.005). Neither maternal HIV infection nor ethnicity had a significant effect on respiratory mechanics. Conclusions: The forced oscillation technique is sensitive enough to demonstrate the effects of tobacco smoke exposure and sex in respiratory mechanics in healthy infants. This technique will facilitate assessing perinatal influences of lung function in infancy

    Computer-controlled apparatus for automated development of continuous flow methods

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    An automated apparatus to assist in the development of analytical continuous flow methods is described. The system is capable of controlling and monitoring a variety of pumps, valves, and detectors through an IBM PC-AT compatible computer. System components consist of two types of peristaltic pumps (including a multiple pump unit), syringe pumps, electrically and pneumatically actuated valves, and an assortment of spectrophotometric and electrochemical detectors. Details of the interface circuitry are given where appropriate. To demonstrate the utility of the system, an automatically generated response surface is presented for the flow injection determination of iron(II) by its reaction with 1,10-phenanthroline

    Severity and persistence of asthma and mental health: a birth cohort study

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    Background. The goal of the current study was to investigate asthma and mental health among youth in the community, and to consider the role of asthma severity and persistence in this link

    Cutoff for the Ising model on the lattice

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    Introduced in 1963, Glauber dynamics is one of the most practiced and extensively studied methods for sampling the Ising model on lattices. It is well known that at high temperatures, the time it takes this chain to mix in L1L^1 on a system of size nn is O(log⁥n)O(\log n). Whether in this regime there is cutoff, i.e. a sharp transition in the L1L^1-convergence to equilibrium, is a fundamental open problem: If so, as conjectured by Peres, it would imply that mixing occurs abruptly at (c+o(1))log⁥n(c+o(1))\log n for some fixed c>0c>0, thus providing a rigorous stopping rule for this MCMC sampler. However, obtaining the precise asymptotics of the mixing and proving cutoff can be extremely challenging even for fairly simple Markov chains. Already for the one-dimensional Ising model, showing cutoff is a longstanding open problem. We settle the above by establishing cutoff and its location at the high temperature regime of the Ising model on the lattice with periodic boundary conditions. Our results hold for any dimension and at any temperature where there is strong spatial mixing: For Z2\Z^2 this carries all the way to the critical temperature. Specifically, for fixed d≄1d\geq 1, the continuous-time Glauber dynamics for the Ising model on (Z/nZ)d(\Z/n\Z)^d with periodic boundary conditions has cutoff at (d/2λ∞)log⁥n(d/2\lambda_\infty)\log n, where λ∞\lambda_\infty is the spectral gap of the dynamics on the infinite-volume lattice. To our knowledge, this is the first time where cutoff is shown for a Markov chain where even understanding its stationary distribution is limited. The proof hinges on a new technique for translating L1L^1 to L2L^2 mixing which enables the application of log-Sobolev inequalities. The technique is general and carries to other monotone and anti-monotone spin-systems.Comment: 34 pages, 3 figure

    Children's environmental health: an under-recognised area in paediatric health care

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    The knowledge that the environment in which we live, grow and play, can have negative or positive impacts on our health and development is not new. However the recognition that adverse environments can significantly and specifically affect the growth and development of a child from early intrauterine life through to adolescence, as well as impact their health later in adulthood, is relatively recent and has not fully reached health care providers involved in paediatric care

    LAPORAN INDIVIDU KEGIATAN PENGALAMAN LAPANGAN (PPL) PERIODE 18 JULI s.d 15 SEPTEMBER 2016 SMA NEGERI 2 BANGUNTAPAN

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    Praktik Pengalaman Lapangan (PPL) merupakan suatu wadah untuk menerapkan/mengaplikasikan ilmu yang selama ini telah dipelajari dalam bidang keahlian maupun ilmu keguruan yang berkaitan dengan peserta didik dalam proses belajar mengajar. Praktik pengalaman lapangan atau praktik mengajar ini mulai dilaksanakan pada tanggal 18 Juli s.d. 15 September 2016 berlokasi di SMA N 2 Banguntapan. Dalam praktik mengajar mahasiswa terlebih dahulu melaksanakan persiapan pembelajaran, yaitu membuat perencanaan pembelajaran dimulai dengan membuat rencana pelaksanaan pembelajaran sampai dengan evaluasi yang dilaksanakan. Kemudian melakukan koordinasi dan konsultasi kepada guru pembimbing di sekolah tersebut. Dalam bimbingan PPL, mahasiswa (penulis) mendapatkan kesempatan untuk melaksanakan pembelajaran di kelas X IPS 1 dan X IPS 2. Kurikulum yang digunakan adalah Kurikulum 2013 (K13). Begitu pula dengan penulisan Rencana Pelaksanaan Pembelajarannya (RPP), penggunaan metode pembelajaran yang diterapkan adalah dengan metode Problem Based Learning dan Cooperative Learning. Sedangkan media yang digunakan adalah White Board, LCD, spidol, lembar kerja dan mengadakan tugas individu untuk mengetahui sejauh mana kemampuan siswa dalam memahami materi yang telah disampaikan. Pada tahap pelaksanaan, mahasiswa mengajar sebanyak 6 kali dengan alokasi masingmasing 3 jam pelajaran setiap pertemuan. Program kegiatan PPL dapat terlaksana dengan baik dan lancar berkat adanya bimbingan dan arahan dari guru pembimbing dan dosen pembimbing selama praktik mengajar serta peran aktif peserta didik selama berlangsungnya KBM. Selain itu terlaksananya program PPL ini tidak terlepas dari dukungan dan bantuan dari pihak sekolah yang telah memberikan keluasan kesempatan kepada para mahasiswa PPL untuk mengembangkan potensi yang dimilikinya
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