187 research outputs found

    Vibrational States of Glassy and Crystalline Orthotherphenyl

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    Low-frequency vibrations of glassy and crystalline orthoterphenyl are studied by means of neutron scattering. Phonon dispersions are measured along the main axes of a single crystal, and the corresponding longitudinal and transversal sound velocities are obtained. For glassy and polycrystalline samples, a density of vibrational states is determined and cross-checked against other dynamic observables. In the crystal, low-lying zone-boundary modes lead to an excess over the Debye density of states. In the glass, the boson peak is located at even lower frequencies. With increasing temperature, both glass and crystal show anharmonicity.Comment: 7 pages of LaTeX (svjour), 2 tables, 10 figures accepted in Eur. Phys. J.

    GAMBARAN HISTOLOGI DAGING AYAM KAMPUNG (Gallus domesticus) YANG DIBERIKAN EKSTRAK DAUN BELIMBING WULUH (Averrhoa bilimbi)

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    Star fruit leaf (Averrhoa bilimbi) in this study were extracted making use of the maceration method and the solvent was absolute ethanol. This study aims to see the effect on free-range chicken meat due to the administration of wuluh starfruit leaf extract. Histological description of the meat was taken from the chest muscle (M. pectoralis) and thigh muscle (M. femoralis) which had previously been treated with starfruit leaf extract. The analysis was carried out descriptively by looking at the histology of free-range chicken meat and compared with the normal picture. The results indicated there is no effect between the administration of starfruit leaf extract on the histology of native chicken meat. It can be seen that the muscle structure is normal, there are no dimensions and shape-changing of the muscle fibers and connective tissue. Conclusions can be drawn that the antibacterial ability of starfruit leaf, shows no effect on the chest and thigh muscles structure of native chickens

    Keragaman Endoparasit Gastrointestinal dan Profil Darah pada Ayam Kampung (Gallus Domesticus)

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    Penelitian ini bertujuan untuk mengetahui keragaman jenis endoparasit gastrointestinal dan pengaruhnya terhadap profil darah ayam kampung yang meliputi jumlah eritrosit, kadar hemoglobin, Packed cell volume, dan jumlah total leukosit. Pengambilan sampel feses dan darah ayam kampung dilapangan sedangkan pemeriksaan dan identifkasi endoparasit pada feses ayam kampung serta pemeriksaan darah di laboratorium Kesehatan Hewan Program Studi Kesehatan Hewan Politani Kupang. Peubah yang diamati adalah morfologi atau ciri-ciri endoparasit dan gambaran darah terutama jumlah eritrosit, kadar hemoglobin, Packed cell volume, dan jumlah total leukosit Seluruh sampel yang terkumpul diidentifikasi menggunakan mikroskop dibantu dengan panduan kunci identifikasi dan didokumentasikan menggunakan kamera digital, dan data gambaran darah yang diperoleh akan disesuakan dengan gambaran darah normal kemudian semua data yang diperoleh, diolah secara deskriptif. Penelitian ini akan dilaksanakan didaerah Kecamatan Amarasi Kabupaten Kupang. Dari pemeriksaan ditemukan telur cacing Ascaridia galli untuk semua sampel feses dan pemeriksaan darah menunjukkan bahwa jumlah eritrosit 3.782 X 10^6/”L, kadar hemoglobin 12.16  g/L, PCV 43.18%, dan jumlah total leukosit 112.5 X 10^3/”L

    Study of the pd→3HeK+K−pd\to ^3\textrm{He} K^+K^- and pd→3Heϕpd\to ^3\textrm{He} \phi reactions close to threshold

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    Two--kaon production in proton--deuteron collisions has been studied at three energies close to threshold using a calibrated magnetic spectrograph to measure the final 3^3He and a vertex detector to measure the K+K−K^+K^- pair. Differential and total cross sections are presented for the production of ϕ\phi--mesons, decaying through ϕ→K+K−\phi\to K^+K^-, as well as for prompt K+K−K^+K^- production. The prompt production seems to follow phase space in both its differential distributions and in its energy dependence. The amplitude for the pd→3pd\to ^3{He}ϕ \phi reaction varies little for excess energies below 22 MeV and the value is consistent with that obtained from a threshold measurement. The angular distribution of the K+K−K^+K^- decay pair shows that near threshold the ϕ\phi--mesons are dominantly produced with polarization m=0m=0 along the initial proton direction. No conclusive evidence for f0(980)f_0(980) production is found in the data.Comment: 13 figure

    Lung Function Is Associated with Arterial Stiffness in Children

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    BACKGROUND: In older adults, an independent association exists between impaired lung function and cardiovascular disease. This interaction might be related to the effects of aging and/or smoking. In order to explore possible childhood antecedents to this association, we hypothesized that decreased lung function and vascular stiffness might be related, in early life. OBJECTIVE: To determine the relationship between lung function and carotid augmentation index (AIx), a measure of vascular stiffness, in 8-year old children. METHODS: Data on brachial blood pressure, lung function (FEV(1), FVC, FEV(1)/FVC, obtained by spirometry) and carotid AIx75 (AIx standardised to an arbitrary heart rate of 75 beats per minute, obtained by applanation tonometry) was available in 249 community-based 8-year old children. These healthy children had been subjects in a randomised controlled trial of two interventions (omega-3 fatty acid supplementation and house-dust mite avoidance) to prevent asthma. Smoking in pregnancy and childhood environmental tobacco smoke (ETS) exposure was prospectively collected by questionnaire. The association between lung function and carotid AIx75 was assessed in multivariate models that included sex, height, smoking status during pregnancy, ETS exposure and randomisation groups (house dust mite avoidance and dietary intervention) as covariates. RESULTS: In the fully adjusted models, Carotid AIx75 was independently associated with FEV1 (standardised ÎČ = -0.17,b = -6.72, partial R(2) = .02, p = 0.03), FVC (standardised ÎČ = -0.29, b = -9.31, partial R(2) = 0.04, p<0.001) and FEV1/FVC (standardised ÎČ = .13, b = 18.4, partial R(2) = 0.02, p = 0.04). CONCLUSION: Lower lung volumes are associated with increased vascular stiffness at an early age. The interaction between lung function and vascular stiffness may thus represent more than just age-related alterations in both the pulmonary and vascular systems

    Experimental study of the pd(d p) → 3 He ππ reactions close to threshold

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    New experimental data on the pd → 3 He π+π− reaction obtained with the COSY-MOMO detector below the three-pion threshold are presented. The reaction was also studied in inverse kinematics with a deuteron beam and the higher counting rates achieved were especially important at low excess energies. The comparison of these data with inclusive pd → 3 He X0 rates allowed estimates also to be made of π0π0 production. The results confirm our earlier findings that, close to threshold, there is no enhancement at low excitation energies in the π+π− system, where the data seem largely suppressed compared with phase space. Possible explanations for this behavior, such as strong p waves in the π+π− system or the influence of two-step processes, are explored

    Land–atmosphere interactions in sub-polar and alpine climates in the CORDEX Flagship Pilot Study Land Use and Climate Across Scales (LUCAS) models – Part 2: The role of changing vegetation

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    Land cover in sub-polar and alpine regions of northern and eastern Europe have already begun changing due to natural and anthropogenic changes such as afforestation. This will impact the regional climate and hydrology upon which societies in these regions are highly reliant. This study aims to identify the impacts of afforestation/reforestation (hereafter afforestation) on snow and the snow-albedo effect and highlight potential improvements for future model development. The study uses an ensemble of nine regional climate models for two different idealised experiments covering a 30-year period; one experiment replaces most land cover in Europe with forest, while the other experiment replaces all forested areas with grass. The ensemble consists of nine regional climate models composed of different combinations of five regional atmospheric models and six land surface models. Results show that afforestation reduces the snow-albedo sensitivity index and enhances snowmelt. While the direction of change is robustly modelled, there is still uncertainty in the magnitude of change. The greatest differences between models emerge in the snowmelt season. One regional climate model uses different land surface models which shows consistent changes between the three simulations during the accumulation period but differs in the snowmelt season. Together these results point to the need for further model development in representing both grass–snow and forest–snow interactions during the snowmelt season. Pathways to accomplishing this include (1) a more sophisticated representation of forest structure, (2) kilometre-scale simulations, and (3) more observational studies on vegetation–snow interactions in northern Europe

    Distinguishing Asthma Phenotypes Using Machine Learning Approaches.

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    Asthma is not a single disease, but an umbrella term for a number of distinct diseases, each of which are caused by a distinct underlying pathophysiological mechanism. These discrete disease entities are often labelled as asthma endotypes. The discovery of different asthma subtypes has moved from subjective approaches in which putative phenotypes are assigned by experts to data-driven ones which incorporate machine learning. This review focuses on the methodological developments of one such machine learning technique-latent class analysis-and how it has contributed to distinguishing asthma and wheezing subtypes in childhood. It also gives a clinical perspective, presenting the findings of studies from the past 5 years that used this approach. The identification of true asthma endotypes may be a crucial step towards understanding their distinct pathophysiological mechanisms, which could ultimately lead to more precise prevention strategies, identification of novel therapeutic targets and the development of effective personalized therapies
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