1,954 research outputs found
Prospective five-year subsidence analysis of a cementless fully hydroxyapatite-coated femoral hip arthroplasty component
Early subsidence >1.5 mm is considered to be a predictive factor for later aseptic loosening of the femoral component following total hip arthroplasty (THA). The aim of this study was to assess five-year subsidence rates of the cementless hydroxyapatite-coated twinSys stem (Mathys Ltd., Bettlach, Switzerland).This prospective single-surgeon series examined consecutive patients receiving a twinSys stem at Maria Middelares Hospital, Belgium. Patients aged >85 years or unable to come to follow-up were excluded. Subsidence was assessed using Ein Bild Roentgen Analyse--Femoral Component Analysis (EBRA-FCA). Additional clinical and radiographic assessments were performed. Follow-ups were prospectively scheduled at two, five, 12, 24, and 60 months.In total, 218 THA (211 patients) were included. At five years, mean subsidence was 0.66 mm (95% CI: 0.43-0.90). Of the 211 patients, 95.2% had an excellent or good Harris Hip Score. There were few radiological changes. Kaplan-Meier analysis indicated five-year stem survival to be 98.4% (95% CI: 97.6-100%).Subsidence levels of the twinSys femoral stem throughout the five years of follow-up were substantially lower than the 1.5 mm level predictive of aseptic loosening. This was reflected in the high five-year survival rate
X-band noise temperature effects of rain on DSN antenna feedhorns
Simulated rain tests were carried out to determine the noise temperature contribution of liquid water adhering to the aperture cover material on both a standard DSN X-band feedhorn and on an S/X-band common aperture feedhorn. It was found that for the particular common aperture feedhorn tested, system noise temperature increases were much greater when the plastic horn cover material was old and weathered than when it was new. The age and condition of the aperture cover material is believed to be a major factor in the amount of degradation experienced by a telecommunications system during rain events
AutoParallel: A Python module for automatic parallelization and distributed execution of affine loop nests
The last improvements in programming languages, programming models, and
frameworks have focused on abstracting the users from many programming issues.
Among others, recent programming frameworks include simpler syntax, automatic
memory management and garbage collection, which simplifies code re-usage
through library packages, and easily configurable tools for deployment. For
instance, Python has risen to the top of the list of the programming languages
due to the simplicity of its syntax, while still achieving a good performance
even being an interpreted language. Moreover, the community has helped to
develop a large number of libraries and modules, tuning them to obtain great
performance.
However, there is still room for improvement when preventing users from
dealing directly with distributed and parallel computing issues. This paper
proposes and evaluates AutoParallel, a Python module to automatically find an
appropriate task-based parallelization of affine loop nests to execute them in
parallel in a distributed computing infrastructure. This parallelization can
also include the building of data blocks to increase task granularity in order
to achieve a good execution performance. Moreover, AutoParallel is based on
sequential programming and only contains a small annotation in the form of a
Python decorator so that anyone with little programming skills can scale up an
application to hundreds of cores.Comment: Accepted to the 8th Workshop on Python for High-Performance and
Scientific Computing (PyHPC 2018
Modulational instability, wave breaking and formation of large scale dipoles in the atmosphere
In the present Letter we use the Direct Numerical Simulation (DNS) of the
Navier-Stokes equation for a two-phase flow (water and air) to study the
dynamics of the modulational instability of free surface waves and its
contribution to the interaction between ocean and atmosphere. If the steepness
of the initial wave is large enough, we observe a wave breaking and the
formation of large scale dipole structures in the air. Because of the multiple
steepening and breaking of the waves under unstable wave packets, a train of
dipoles is released and propagate in the atmosphere at a height comparable with
the wave length. The amount of energy dissipated by the breaker in water and
air is considered and, contrary to expectations, we observe that the energy
dissipation in air is larger than the one in the water. Possible consequences
on the wave modelling and on the exchange of aerosols and gases between air and
water are discussed
Evolutionary adaptations of ruminants and their potential relevance for modern production systems
Comparative physiology applies methods established in domestic animal science to a wider variety of species. This can lead to improved insight into evolutionary adaptations of domestic animals, by putting domestic species into a broader context. Examples include the variety of responses to seasonally fluctuating environments, different adaptations to heat and drought, and in particular adaptations to herbivory and various herbivore niches. Herbivores generally face the challenge that a high food intake compromises digestive efficiency (by reducing ingesta retention time and time available for selective feeding and for food comminution), and a variety of digestive strategies have evolved in response. Ruminants are very successful herbivores. They benefit from potential advantages of a forestomach without being constrained in their food intake as much as other foregut fermenters, because of their peculiar reticuloruminal sorting mechanism that retains food requiring further digestion but clears the forestomach of already digested material; the same mechanism also optimises food comminution. Wild ruminants vary widely in the degree to which their rumen contents ‘stratify', with little stratification in ‘moose-type' ruminants (which are mostly restricted to a browse niche) and a high degree of stratification into gas, particle and fluid layers in ‘cattle-type' ruminants (which are more flexible as intermediate feeders and grazers). Yet all ruminants uniformly achieve efficient selective particle retention, suggesting that functions other than particle retention played an important role in the evolution of stratification-enhancing adaptations. One interesting emerging hypothesis is that the high fluid turnover observed in ‘cattle-type' ruminants - which is a prerequisite for stratification - is an adaptation that not only leads to a shift of the sorting mechanism from the reticulum to the whole reticulo-rumen, but also optimises the harvest of microbial protein from the forestomach. Although potential benefits of this adaptation have not been quantified, the evidence for convergent evolution toward stratification suggests that they must be substantial. In modern production systems, the main way in which humans influence the efficiency of energy uptake is by manipulating diet quality. Selective breeding for conversion efficiency has resulted in notable differences between wild and domestic animals. With increased knowledge on the relevance of individual factors, that is fluid throughput through the reticulo-rumen, more specific selection parameters for breeding could be defined to increase productivity of domestic ruminants by continuing certain evolutionary trajectorie
Desynchronization of pathological low-frequency brain activity by the hypnotic drug zolpidem.
Reports of the beneficial effects of the hypnotic imidazopyridine, zolpidem, described in persistent vegetative state^1, 2^ have been replicated recently in brain-injured and cognitively impaired patients^3-7^. Previous single photon emission computed tomography (SPECT) studies have suggested that sub-sedative doses of zolpidem increased regional cerebral perfusion in affected areas^5, 8^, implying enhanced neuronal metabolic activity; which has led to speculation that zolpidem 'reawakens' functionally dormant cortex. However, a neuronal mechanism by which this hypnotic drug affords benefits to brain injured patients has yet to be demonstrated. Here, we report the action of sub-sedative doses of zolpidem on neuronal network oscillatory activity in human brain, measured using pharmaco-magnetoencephalography (pharmaco-MEG). Study participant JP suffered a stroke in 1996, causing major damage to the left hemisphere that impaired aspects of both motor and cognitive function. Pharmaco-MEG analyses revealed robust and persistent pathological theta (4-10Hz) and beta (15-30Hz) oscillations within the lesion penumbra and surrounding cortex. Administration of zolpidem (5mg) reduced the power of pathological theta and beta oscillations in all regions of the lesioned hemisphere. This desynchronizing effect correlated well with zolpidem uptake (occurring approximately 40 minutes after acute administration) and was coincident with marked improvements in cognitive and motor function. Control experiments revealed no effect of placebo, while a structurally unrelated hypnotic, zopiclone, administered at a comparable dose (3.5mg) elicited widespread increases in cortical oscillatory power in the beta (15-30Hz) band without functional improvement. These results suggest that in JP, specific motor and cognitive impairments are related to increased low-frequency oscillatory neuronal network activity. Zolpidem is unique amongst hypnotic drugs in its ability to desynchronize such pathological low-frequency activity, thereby restoring cognitive function
"Metharmo" is setting the standards - joint european research project develops standards for determining methane emissions from anaerobic digestion plants
Particle size distribution in commercial pig compound feeds in Switzerland: survey and methodological considerations
Abstracts: English - Deutsch - Français - Italiano
English
Particle size distribution in commercial pig compound feeds in Switzerland: survey and methodological considerations
The grinding intensity of pig feed is considered one potential predisposing factor for gastric ulcers, and a variety of particle size recommendations have been published for pig feeds. We subjected 51 different commercial compound feeds for pigs (38 meals, 13 pellets/granulates) to dry and/or wet sieve analysis. The amount of particles passing the finest sieve (or being soluble) was estimated by the difference to the total dry matter weighed prior to sieving. Mean particle size was calculated based on the weighted average of the material retained on the sieves (MPSsieves), and additionally with accounting for this lost material (MPStotal). Dry sieve analysis of the meals yielded MPSsieves of 0,58–2,90 mm and MPStotal of 0,58–2,89 mm; only 0,02 to 2,71 % of the dry matter passed all sieves. Wet sieve analysis of all meals and pellets yielded similar MPSsieves of 0,63–1,66 mm, but dramatically lower MPStotal of 0,26–1,04 mm; between 35 and 66 % of the dry matter was not retained on the sieves. Pellets had smaller MPS, and a higher proportion of particles passing all sieves than meals. Depending on the reference used, a maximum of 26 % of meals conformed to recommendations for pig feed particle size. None of the pelleted feeds met these criteria, irrespective of the source consulted for the recommendation. Wet sieving should be considered the standard analysis, because in dry sieving, very fine particles adhering to larger particles may not be registered separately but contribute erroneously to larger particle weight. In addition, the MPS calculation should account for material lost through the finest sieve. Reasons why Swiss pig feed does not meet particle size recommendations should be further investigated.
Keywords: Diet, ulcer, stomach health, prevention, grinding
Deutsch
Partikelgrösse in kommerziellen Schweinefuttermischungen in der Schweiz: Erhebung und methodische Überlegungen
Das Ausmass der Zerkleinerung von Schweinefutter wird als ein möglicher prädisponierender Faktor für Magengeschwüre angesehen. Für Schweinefutter wurden verschiedene Empfehlungen zur Partikelgrösse veröffentlicht. Wir haben 51 verschiedene handelsübliche Mischfuttermittel für Schweine (38 Mehle, 13 Pellets/Granulate) einer Trocken – und/oder Nass-Siebanalyse unterzogen. Die Menge an Partikeln, die das feinste Sieb passierten (oder löslich waren), wurde durch die Differenz zu der vor dem Sieben gewogenen Gesamttrockenmasse abgeschätzt. Die mittlere Partikelgrösse wurde basierend auf Mittelwert des Gewichtes von dem im Sieb zurückgehaltenen Materials (MPSsieves) unter Berücksichtigung dieses verlorenen Materials (MPStotal) berechnet. Die Trocken-Siebanalyse der Mischungen ergab MPSSiebe von 0,58–2,90 mm und MPStotal von 0,58–2,89 mm; nur 0,02 bis 2,71 % der Trockenmasse passierten alle Siebe. Die Nass-Siebanalyse aller Mehle und Pellets ergab ähnliche MPSSiebe von 0,63–1,66 mm, aber signifikant niedrigere MPStotal von 0,26–1,04 mm; zwischen 35 und 66 % der Trockenmasse wurden nicht auf den Sieben zurückgehalten. Pellets hatten im Vergleich zu den Fütterungsmehlen eine kleinere MPS und einen höheren Anteil an Partikeln, die alle Siebe passierten. Je nach verwendeter Referenz entsprachen maximal 26 % der Fütterungsmehle den Empfehlungen für die Partikelgrösse von Schweinefutter. Unabhängig der konsultierten Referenzliteratur erfüllte keine der pelletierten Futtermittel diese Kriterien. Die Nass-Siebung sollte als Standardanalyse angesehen werden, da bei der Trocken-Siebung sehr feine Partikel, die an grösseren Partikeln anhaften, möglicherweise nicht separat erfasst werden, sondern fälschlicherweise zu einem grösseren Partikelgewicht beitragen. Zusätzlich sollte die MPS-Berechnung den Materialverlust durch das feinste Sieb berücksichtigen. Weiter Untersuchungen sollten die Gründe abklären, warum Schweizer Schweinefutter die Empfehlungen zur Partikelgrösse nicht erfüllen.
Schlüsselwörter: Diät, Magengeschwür, Magengesundheit, Vorbeugung, Zerkleinerung
Français
Taille des particules dans les aliments composés commerciaux pour porcs en Suisse: enquête et considérations méthodologiques
L’intensité de broyage des aliments pour porcs est considérée comme un facteur potentiel de prédisposition aux ulcères gastriques et diverses recommandations sur la taille des particules ont été publiées pour les aliments pour porcs. Nous avons soumis 51 différents aliments composés commerciaux pour porcs (38 farines, 13 pellets/granulés) à une analyse par tamisage à sec et/ou humide. La quantité de particules passant le tamis le plus fin (ou étant solubles) a été estimée par la différence avec la matière sèche totale pesée avant le tamisage. La taille moyenne des particules a été calculée sur la base des moyennes pondérées du matériel retenu sur les tamis (MPSsieves) en tenant compte en plus du matériel perdu (MPStotal). L’analyse des mélanges par tamisage à sec a donné des MPSsieves de 0,58–2,90 mm et des MPStotal de 0,58–2,89 mm ; seule 0,02 à 2,71 % de la matière sèche a passé tous les tamis. L’analyse par tamisage humide de toutes les farines et des granulés a donné des MPSsieves similaires de 0,63–1,66 mm, mais des MPStotal nettement inférieurs de 0,26–1,04 mm ; entre 35 et 66 % de la matière sèche n’a pas été retenue sur les tamis. Les granulés présentaient des MPS plus faibles et une proportion plus élevée de particules passant par tous les tamis que les farines. Selon la référence utilisée, un maximum de 26 % des farines étaient conformes aux recommandations relatives à la taille des particules des aliments pour porcs. Aucun des aliments granulés ne répondait à ces critères, quelle que soit la source consultée pour la recommandation. Le tamisage humide devrait être considéré comme l’analyse standard car, dans le tamisage sec, les particules très fines adhérant à des particules plus grosses peuvent ne pas être enregistrées séparément mais contribuer de manière erronée au poids des particules plus grosses. En outre, le calcul du MPS devrait tenir compte de la matière perdue par le tamis le plus fin. Les raisons pour lesquelles les aliments pour porcs suisses ne répondent pas aux recommandations sur la taille des particules devraient être étudiées plus en détail.
Mots-clés: Régime alimentaire, ulcère gastrique, santé gastrique, prévention, broyage
Italiano
Dimensioni granulometriche nelle miscele commerciali di mangimi per suini in Svizzera: indagine e considerazioni metodologiche
Il grado di sminuzzamento dei mangimi per suini è considerato un possibile fattore predisponente alle ulcere gastriche e sono state pubblicate diverse raccomandazioni sulla dimensione dei granuli per i mangimi dei suini. Abbiamo sottoposto 51 diverse miscele di mangimi commerciali per suini (38 farine, 13 pellet/granuli) all’analisi del setaccio a secco e/o a umido. La quantità di particelle che hanno superato il setaccio più fine (o che erano solubili) è stata stimata dalla differenza rispetto alla sostanza secca totale pesata prima della setacciatura. La dimensione media delle particelle (DMP) è stata calcolata in base al peso medio del materiale trattenuto nel setaccio (DMPsetacci) tenendo conto del materiale perso (DMPtotale). L’analisi dei setacci a secco delle miscele ha mostrato una DMPsetacci di 0,58-2,90 mm e una DMPtotale di 0,58–2,89 mm; solo lo 0,02–2,71 % della sostanza secca ha superato tutti i setacci. L’analisi al setaccio umido di tutte le farine e dei pellet ha mostrato una DMPsetacci analoghi di 0,63-1,66 mm, ma con una DMPtotale significativamente inferiore di 0,26–1,04 mm; tra il 35 e il 66 % della sostanza secca non è stata trattenuta dai setacci. I pellet presentavano una DMP inferiore e una percentuale maggiore di particelle che passavano tutti i setacci rispetto alle farine. A seconda del riferimento utilizzato, un massimo del 26 % delle farine soddisfaceva le raccomandazioni sulla dimensione delle particelle nei mangimi per suini. Mentre, indipendentemente dalla letteratura di riferimento consultata, nessuno dei mangimi a pellet soddisfaceva le raccomandazioni. La setacciatura a umido deve essere considerata l’analisi standard, poiché la setacciatura a secco potrebbe non rilevare separatamente le particelle molto fini che aderiscono a quelle più grandi, ma che contribuiscono erroneamente a un peso maggiore delle particelle. Inoltre, il calcolo della DMP deve tenere conto della perdita di materiale attraverso il setaccio più fine. Ulteriori indagini dovrebbero chiarire le ragioni per cui i mangimi per suini svizzeri non soddisfano le raccomandazioni sulle dimensioni delle particelle.
Parole chiavi: dieta, ulcera, salute dello stomaco, prevenzione, macinazion
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