The pulmonary artery catheter: in medio virtus

OBJECTIVE: To clarify the role of the pulmonary artery catheter in the intensive care unit. DATA SOURCES: Recent and relevant literature from MEDLINE and authors' personal databases. STUDY SELECTION: Studies on pulmonary artery catheter use and use of other monitoring devices in critically ill patients. DATA EXTRACTION: Based largely on clinical experience and assessment of the relevant published literature and in response to recent articles attacking the pulmonary artery catheter, we propose that the pulmonary artery catheter is still a valuable tool for the hemodynamic monitoring of patients with complex disease processes in whom the information obtained from the pulmonary artery catheter may influence management. We suggest that there is a need to revisit the basics of hemodynamic management and reassess the way in which the pulmonary artery catheter is used, applying three key principles: correct measurement, correct data interpretation, and correct application. CONCLUSION: The pulmonary artery catheter is still a valuable tool for hemodynamic monitoring when used in selected patients and by physicians adequately trained to correctly interpret and apply the data provided.

Neutron capture on Pt isotopes in iron meteorites and the Hf–W chronology of core formation in planetesimals

The short-lived 182Hf–182W isotope system can provide powerful constraints on the timescales of planetary core formation, but its application to iron meteorites is hampered by neutron capture reactions on W isotopes resulting from exposure to galactic cosmic rays. Here we show that Pt isotopes in magmatic iron meteorites are also affected by capture of (epi)thermal neutrons and that the Pt isotope variations are correlated with variations in 182W/184W. This makes Pt isotopes a sensitive neutron dosimeter for correcting cosmic ray-induced W isotope shifts. The pre-exposure 182W/184W derived from the Pt–W isotope correlations of the IID, IVA and IVB iron meteorites are higher than most previous estimates and are more radiogenic than the initial 182W/184W of Ca–Al-rich inclusions (CAI). The Hf–W model ages for core formation range from +1.6±1.0 million years (Ma; for the IVA irons) to +2.7±1.3 Ma after CAI formation (for the IID irons), indicating that there was a time gap of at least ∼1 Ma between CAI formation and metal segregation in the parent bodies of some iron meteorites. From the Hf–W ages a time limit of <1.5–2 Ma after CAI formation can be inferred for the accretion of the IID, IVA and IVB iron meteorite parent bodies, consistent with earlier conclusions that the accretion of differentiated planetesimals predated that of most chondrite parent bodies.

The abundance and isotopic composition of Cd in iron meteorites

Cadmium is a highly volatile element and its abundance in meteorites may help better understand volatility-controlled processes in the solar nebula and on meteorite parent bodies. The large thermal neutron capture cross section of 113Cd suggests that Cd isotopes might be well suited to quantify neutron fluences in extraterrestrial materials. The aims of this study were (1) to evaluate the range and magnitude of Cd concentrations in magmatic iron meteorites, and (2) to assess the potential of Cd isotopes as a neutron dosimeter for iron meteorites. Our new Cd concentration data determined by isotope dilution demonstrate that Cd concentrations in iron meteorites are significantly lower than in some previous studies. In contrast to large systematic variations in the concentration of moderately volatile elements like Ga and Ge, there is neither systematic variation in Cd concentration amongst troilites, nor amongst metal phases of different iron meteorite groups. Instead, Cd is strongly depleted in all iron meteorite groups, implying that the parent bodies accreted well above the condensation temperature of Cd (i.e., ≈650 K) and thus incorporated only minimal amounts of highly volatile elements. No Cd isotope anomalies were found, whereas Pt and W isotope anomalies for the same iron meteorite samples indicate a significant fluence of epithermal and higher energetic neutrons. This observation demonstrates that owing to the high Fe concentrations in iron meteorites, neutron capture mainly occurs at epithermal and higher energies. The combined Cd-Pt-W isotope results from this study thus demonstrate that the relative magnitude of neutron capture-induced isotope anomalies is strongly affected by the chemical composition of the irradiated material. The resulting low fluence of thermal neutrons in iron meteorites and their very low Cd concentrations make Cd isotopes unsuitable as a neutron dosimeter for iron meteorites.

Laufbahnen von ehemaligen Schweizer Nachwuchs-Elite-Athleten unter dem Aspekt des Erfolgs

Die vorliegende Dissertation verfolgt das Ziel, zu untersuchen, wie sich ehemalige Schweizer Nachwuchs-Elite-Athleten unter dem Aspekt des sportlichen Erfolgs entwickelt haben und wie sich ihre heutige Lebenssituation präsentiert. Zudem will die Arbeit ergründen, inwiefern der sportliche Erfolg durch ausgewählte institutionelle, sportwissenschaftliche und individuelle Parameter vorhergesagt werden kann. Zu diesem Zweck wurden alle deutschsprachigen Nachwuchs-Elite-Athleten untersucht (N = 221), welche im Jahre 1999 Inhaber einer Swiss Olympic Talent-Card waren. Die Prädiktoren stammen teilweise aus einer ersten schriftlichen Befragung, welche 1999 durchgeführt wurde (Rücklauf: 79%). Die Daten für die Beschreibung der Laufbahn sowie der heutigen Situation wurden im Sommer 2011 durch eine weitere schriftliche Befragung erhoben (Rücklauf: 48%). Die Daten wurden mit deskriptiven, inferenzstatistischen, cluster- sowie regressionsanalytischen Verfahren ausgewertet. Die Resultate zeichnen insgesamt ein positives Bild. Trotz verschiedener Hürden im Nachwuchsalter schafften die meisten befragten Athleten den Sprung in die Elite-Stufe. Knapp ein Drittel von ihnen konnte dabei grosse Erfolge (Medaillengewinn) an bedeutenden internationalen Wettkämpfen erringen. Die bereits zurückgetretenen Athleten scheinen das Laufbahnende grösstenteils gut bewältigt zu haben, was wohl damit zusammenhängt, dass die Mehrheit von ihnen freiwillig zurückgetretenen ist und konkrete Pläne für die nachsportliche Laufbahn hatte. Insgesamt deuten die Ergebnisse darauf hin, dass sich ein Engagement im Leistungssport nicht negativ auf die Entwicklung in anderen Lebensbereichen auszuwirken scheint. So zeigte sich, dass sich die heutige Situation der ehemaligen Nachwuchs-Elite-Athleten in gesundheitlicher, psychologischer, sozialer, beruflicher und finanzieller Hinsicht durchwegs positiv präsentiert – in gesundheitlicher, beruflicher und finanzieller Hinsicht sogar besser als jene von gleichaltrigen Vergleichspersonen der Schweizer Bevölkerung. Bei der Vorhersage des sportlichen Erfolgs zeigte sich, dass Athleten aus weniger geförderten und weniger bedeutenden Sportarten später insgesamt erfolgreicher sind an bedeutenden internationalen Wettkämpfen. Darüber hinaus erwies sich die mentale Stärke als langfristiger Erfolgsfaktor. Die Ergebnisse erweitern das bestehende Wissen über Laufbahnen von Leistungssportlern sowie über Determinanten von sportlichem Erfolg generell, besonders aber hinsichtlich des Schweizer Sportsystems. Athleten und ihr Umfeld erhalten dadurch einen vertieften Einblick in die Chancen und Risiken eines Engagements im Leistungssport. Swiss Olympic und die Verbände gewinnen ein besseres Verständnis darüber, wie sich Nachwuchs-Elite-Athleten in ihrer sportlichen Entwicklung noch besser unterstützen lassen. Bund, Kantone und Gemeinden können anhand der Ergebnisse besser abschätzen, inwiefern sich die Förderung des Spitzensports durch öffentliche Gelder rechtfertigen lässt.

Use of early corticosteroid therapy on ICU admission in patients affected by severe pandemic (H1N1)v influenza A infection.

INTRODUCTION Early use of corticosteroids in patients affected by pandemic (H1N1)v influenza A infection, although relatively common, remains controversial. METHODS Prospective, observational, multicenter study from 23 June 2009 through 11 February 2010, reported in the European Society of Intensive Care Medicine (ESICM) H1N1 registry. RESULTS Two hundred twenty patients admitted to an intensive care unit (ICU) with completed outcome data were analyzed. Invasive mechanical ventilation was used in 155 (70.5%). Sixty-seven (30.5%) of the patients died in ICU and 75 (34.1%) whilst in hospital. One hundred twenty-six (57.3%) patients received corticosteroid therapy on admission to ICU. Patients who received corticosteroids were significantly older and were more likely to have coexisting asthma, chronic obstructive pulmonary disease (COPD), and chronic steroid use. These patients receiving corticosteroids had increased likelihood of developing hospital-acquired pneumonia (HAP) [26.2% versus 13.8%, p < 0.05; odds ratio (OR) 2.2, confidence interval (CI) 1.1-4.5]. Patients who received corticosteroids had significantly higher ICU mortality than patients who did not (46.0% versus 18.1%, p < 0.01; OR 3.8, CI 2.1-7.2). Cox regression analysis adjusted for severity and potential confounding factors identified that early use of corticosteroids was not significantly associated with mortality [hazard ratio (HR) 1.3, 95% CI 0.7-2.4, p = 0.4] but was still associated with an increased rate of HAP (OR 2.2, 95% CI 1.0-4.8, p < 0.05). When only patients developing acute respiratory distress syndrome (ARDS) were analyzed, similar results were observed. CONCLUSIONS Early use of corticosteroids in patients affected by pandemic (H1N1)v influenza A infection did not result in better outcomes and was associated with increased risk of superinfections.

Einfluss des Trampolinsprungtuchs und der Sprunghöhe auf die Vertikalbeschleunigung an der Brustwirbelsäule

Die 2011 für das Trampolinturnen eingeführte, instrumentierte Bewertung der Sprunghöhe hatte die Entwicklung wurfstärkerer Sprungtücher und damit eine Zunahme der Sprunghöhen zur Folge. Inwieweit dabei die Beanspruchung des Bewegungsapparates gestiegen ist, wird durch vergleichende biomechanische Analysen verschiedener Sprünge von Athlet/innen des deutschen Nationalkaders auf dem alten 6x4- und dem neuen 4x4 -Sprungtuch untersucht. Erste Analysen zeigten, dass sich die Zunahme der Sprunghöhe auf dem 4x4-Tuch notwendigerweise in einem größeren Kraftstoß begründet, dieser aber nicht durch eine längere Tuchkontaktzeit, sondern durch eine höhere Kraft zustande kommt (Kredel, Eisele, Schweizer, Kuhn & Riehle, 2014). In der Folge soll nun der Einfluss dieser Kraftzunahme auf Bewegungsparameter und Beanspruchung untersucht werden. Kinematische Merkmale von Körper- und Wirbelsäulensegmenten wurden mit einem Vicon-T40s-System aufgezeichnet, während die Bodenreaktionskraftverläufe mit vier Kis t-ler-Kraftmessplatten erfasst wurden. Eine individualisierte, inversdynamische Modellierung der Tuchkontaktphasen soll Aufschluss über die Beanspruchungsunterschiede relevanter Gelenksstrukturen (Sprung-, Knie-, Hüftgelenk, LWS, BWS) geben. Zur Modellvalidierung dient die mittels Beschleunigungssensor erfasste Brustwirbelsäulenkinematik, deren Ausprägung in Bezug zur Sprunghöhe Gegenstand des aktuellen Untersuchungsteils war. Analysen von 102 Standsprüngen zeigen Zusammenhänge zwischen der Sprunghöhe und sowohl der mittleren (4x4: r(44)=.90, p<.001; 6x4: r(54)=.83, p<.001), als auch der maximalen (4x4: r(44)=.65, p<.001; 6x4: r(54)=.80, p<.001) Vertikalbeschleunigung der Brus twirbelsäule während des Tuchkontakts. Sind die Beschleunigungswerte – und damit die Belastungen – im mittleren Sprunghöhenbereich in ähnlichen Größenordnungen, ist festzuhalten, dass die durch das 4x4-Tuch erreichbaren größeren Sprunghöhen nicht nur einen weiteren Anstieg der mittleren, sondern auch eine weitere Erhöhung der maximalen Vertikalbeschleunigung zur Folge haben (Maximum 4x4: 151.4 m/s2 vs. 6x4: 139.6 m/s2) und somit die Maximalbelastung der Athlet/innen zunimmt. Aktuell wird dieser Befund bei den komplexeren Sprungvarianten verifiziert und die Gelenksbeansp.ruchung modelliert

A rapid and efficient ion-exchange chromatography for Lu–Hf, Sm–Nd, and Rb–Sr geochronology and the routine isotope analysis of sub-ng amounts of Hf by MC-ICP-MS

The development and improvement of MC-ICP-MS instruments have fueled the growth of Lu–Hf geochronology over the last two decades, but some limitations remain. Here, we present improvements in chemical separation and mass spectrometry that allow accurate and precise measurements of 176Hf/177Hf and 176Lu/177Hf in high-Lu/Hf samples (e.g., garnet and apatite), as well as for samples containing sub-nanogram quantities of Hf. When such samples are spiked, correcting for the isobaric interference of 176Lu on 176Hf is not always possible if the separation of Lu and Hf is insufficient. To improve the purification of Hf, the high field strength elements (HFSE, including Hf) are first separated from the rare earth elements (REE, including Lu) on a first-stage cation column modified after Patchett and Tatsumoto (Contrib. Mineral. Petrol., 1980, 75, 263–267). Hafnium is further purified on an Ln-Spec column adapted from the procedures of Münker et al. (Geochem., Geophys., Geosyst., 2001, DOI: 10.1029/2001gc000183) and Wimpenny et al. (Anal. Chem., 2013, 85, 11258–11264) typically resulting in Lu/Hf < 0.0001, Zr/Hf < 1, and Ti/Hf < 0.1. In addition, Sm–Nd and Rb–Sr separations can easily be added to the described two-stage ion-exchange procedure for Lu–Hf. The isotopic compositions are measured on a Thermo Scientific Neptune Plus MC-ICP-MS equipped with three 1012 Ω resistors. Multiple 176Hf/177Hf measurements of international reference rocks yield a precision of 5–20 ppm for solutions containing 40 ppb of Hf, and 50–180 ppm for 1 ppb solutions (=0.5 ng sample Hf 0.5 in ml). The routine analysis of sub-ng amounts of Hf will facilitate Lu–Hf dating of low-concentration samples.

Vorstellung deß Wunderbahren Schutzes und Vorsehung Gottes über seine Kinder

Knabe übersteht Sprung aus einem Fenster unverletzt

Abb.9. Mittlerer Energieaufwand einer Feldheuschrecke je Absprung gegen Gewicht des Einzeltieres

Untersuchungen über das Sprungvermögen der Feldheuschreckangattung Stenobothru (277 Individuen) ergaben: 1. Die Sprungbahnen stellen exakte ballistische Kurven dar, Körperbewegungen während des Sprunges haben auf ihre Form keinen wesentlichen Einfluß. Die Verkürzung der Wurfparabel durch den Luftwiderstand beträgt 20%, der mittlere Absprungwinkel 54°. 2. Die Sprungweite eines Weibchen vom mittleren Gewicht 0,22 g beträgt bei etwa 20° im Mittel 0,6 m, mit einem Maximum von 1,2 m. Durch einen Absprungwinkel nahe 45° erzielen die Tiere auf ebener Fläche optimale Sprungweite. 3. Einem solchen Standardsprung entspricht ein physikalischer Energieaufwand von rund 10**4 erg, mit nicht erheblicher empirischer Fehlerbreite. Unter Rücksicht auf den Nutzeffekt dürfte die von einem Tier je Sprung aufgewendete Energie etwas mehr als das 3fache dieses Betrages ausmachen. Als Absprungkraft errechnet sich je Sprung rund 4000 dyn. 4. Im groben verhalten sich große und kleine Vertreter der untersuchten Arten isometrisch, obgleich die großen ausschließlich Weibchen, die kleinen ausschließlich Männchen sind. 5. Die maximale Lokomotionsgeschwindigkeit, gemessen an der ersten Fünfsprungserie, ist bei kleinen und großen Tieren innerhalb der Fehlerbreite absolut gleich, ja bei den kleineren Vertretern sogar (mindestens teilweise vermutlich aus sekundären Gründen) etwas größer. Entsprechendes gilt für eine mittlere Lokomotionsgeschwindigkeit. Überschlagsmäßig würde dauerndes Springen vom Standpunkt der O2-Bilanz keine außergewöhnliche Belastung bedeuten. Die beobachteten Ermüdungserscheinungen beruhen offenbar auf der zu langsamen Mobilisierung gespeicherter Energien. 6. Bei allen guten Springern des Tierreichs (Floh-Känguruh ) scheint größenordnungsmäßig die Sprungleistung massenproportional zu sein.

Wheel-Rail Contact Forces in High-Speed Simply Supported Bridges at Resonance

The response of high-speed bridges at resonance, particularly under flexural vibrations, constitutes a subject of research for many scientists and engineers at the moment. The topic is of great interest because, as a matter of fact, such kind of behaviour is not unlikely to happen due to the elevated operating speeds of modern rains, which in many cases are equal to or even exceed 300 km/h ( [1,2]). The present paper addresses the subject of the evolution of the wheel-rail contact forces during resonance situations in simply supported bridges. Based on a dimensionless formulation of the equations of motion presented in [4], very similar to the one introduced by Klasztorny and Langer in [3], a parametric study is conducted and the contact forces in realistic situations analysed in detail. The effects of rail and wheel irregularities are not included in the model. The bridge is idealised as an Euler-Bernoulli beam, while the train is simulated by a system consisting of rigid bodies, springs and dampers. The situations such that a severe reduction of the contact force could take place are identified and compared with typical situations in actual bridges. To this end, the simply supported bridge is excited at resonace by means of a theoretical train consisting of 15 equidistant axles. The mechanical characteristics of all axles (unsprung mass, semi-sprung mass, and primary suspension system) are identical. This theoretical train permits the identification of the key parameters having an influence on the wheel-rail contact forces. In addition, a real case of a 17.5 m bridges traversed by the Eurostar train is analysed and checked against the theoretical results. The influence of three fundamental parameters is investigated in great detail: a) the ratio of the fundamental frequency of the bridge and natural frequency of the primary suspension of the vehicle; b) the ratio of the total mass of the bridge and the semi-sprung mass of the vehicle and c) the ratio between the length of the bridge and the characteristic distance between consecutive axles. The main conclusions derived from the investigation are: The wheel-rail contact forces undergo oscillations during the passage of the axles over the bridge. During resonance, these oscillations are more severe for the rear wheels than for the front ones. If denotes the span of a simply supported bridge, and the characteristic distance between consecutive groups of loads, the lower the value of , the greater the oscillations of the contact forces at resonance. For or greater, no likelihood of loss of wheel-rail contact has been detected. The ratio between the frequency of the primary suspension of the vehicle and the fundamental frequency of the bridge is denoted by (frequency ratio), and the ratio of the semi-sprung mass of the vehicle (mass of the bogie) and the total mass of the bridge is denoted by (mass ratio). For any given frequency ratio, the greater the mass ratio, the greater the oscillations of the contact forces at resonance. The oscillations of the contact forces at resonance, and therefore the likelihood of loss of wheel-rail contact, present a minimum for approximately between 0.5 and 1. For lower or higher values of the frequency ratio the oscillations of the contact forces increase. Neglecting the possible effects of torsional vibrations, the metal or composite bridges with a low linear mass have been found to be the ones where the contact forces may suffer the most severe oscillations. If single-track, simply supported, composite or metal bridges were used in high-speed lines, and damping ratios below 1% were expected, the minimum contact forces at resonance could drop to dangerous values. Nevertheless, this kind of structures is very unusual in modern high-speed railway lines.

Versuche mit Bier'scher Stauungshyperämie in der Tierheilkunde.

Inaug.-diss.--Leipzig, 1913.

Beiträge zur spezifischen Diagnostik, Prophylaxis und Therapie des infektiösen Abortus der Rinder ...

Lebenslauf.

Of mermaids and spirit men

A late afternoon and two elderly people sit on an old, steel, wire-sprung camp stretcher bed. They sit back-to-back, engaging in commentary on the vehicles and people that pass them by. One of them, the old man, says suddenly, 'Me! I'm number one singer myself!' Without hesitation the old woman says, simply and bluntly, 'Bullshit!' For the next half an hour the dialogue between the two never varies though the utterances increase both in auditory levels and passion. To the outside observer the dialogue seems simple and nonsensical. However in the world of Yanyuwa music, composition and performance these two people - in their old age in the early 1980s - are unique. The old man Jerry Brown Ngarnawakajarra and the old woman Elma Brown a-Bunubunu are the last two people in Yanyuwa society to have had revealed to them what in this article we will call 'dream state' songs.

Manipulating avocado fruit ripening with 1-methylcyclopropene

Previous investigations with 1-methylcyclopropene (1-MCP) on avocado (Persea americana Mill.) fruit have focussed mainly on improving storage life by reducing the severity of disorders causing discolouration of the flesh. Development of 1-MCP and ethylene treatments, which also help control the time to reach the eating ripe stage, may confer additional practical benefits. In this context, the current study investigated the potential of 1-MCP to accurately manipulate ripening of non-stored 'Hass' avocado fruit by treatment before or after ethylene and at different times during ripening. To investigate this, 500 nL L-1 1-MCP was applied within 1 day after harvest, followed by ethylene 0-14 days after 1-MCP. In addition, fruit were treated with ethylene, then 1-MCP 0-8 days after ethylene. Treatment of fruit with 500 nL L-1 1-MCP for 18 h at 20 degreesC provided the maximum effect by increasing the days from harvest to ripe (DTR) from 8 (with no 1-MCP) to 20. Fruit treated with 500 nL L-1 1-MCP for 18 h at 20 degreesC remained insensitive to 100 muL L-1 ethylene applied between 0 and 14 days after 1-MCP for 24 h at 20 degreesC. Ripening of fruit exposed to 100 muL L-1 ethylene for 24 h at 20 degreesC could be delayed by up to 3.3 days by applying 500 nL L-1 1-MCP for 18 h at 20 degreesC up to 2 days after ethylene treatment. However, once the fruit started to soften (sprung) there was little effect of 1-MCP on DTR, compared with no 1-MCP. 1-MCP treatment was associated with increased severity of body rots (caused mainly by Colletotrichum spp.) and stem-end rots (caused mainly by Dothiorella spp.), which was likely due to the increased DTR in these treatments. Significant differences in disease severity were found between orchards (replications), with replicates with low disease severity being less affected by 1-MCP treatment. These results indicate that 1-MCP can delay ripening, but careful sourcing of fruit is required to reduce the risk of diseases in ripe fruit. There is some capacity to delay ripening using 1-MCP after ethylene. There is little potential to control ripening using ethylene after treatment with 500 nL L-1 1-1-MCP, but lower concentrations may be more effective. (C) 2004 Elsevier B.V. All rights reserved.