Wood-ash recycling affects forest soil and tree fine-root chemistry and reverses soil acidification

Wood ash was applied to a forest ecosystem with the aim to recycle nutrients taken from the forest and to mitigate the negative effects of intensive harvesting. After two years, the application of 8,000 kg ha−1 of wood ash increased soil exchangeable Ca and Mg. Similarly, an increase in Ca and Mg in the Norway spruce fine roots was recorded, leading to significant linear correlations between soil and root Ca and soil and root Mg. In contrast to these macronutrients, the micronutrients Fe and Zn and the toxic element Al decreased in the soil exchangeable fraction with the addition of wood ash, but not in the fine roots. Only Mn decreased in soil and in fine roots leading to a significant linear correlation between soil and root Mn. In soil, as well as in fine roots, strong positive correlations were found between the elements Ca and Mg and between Fe and Al. This indicates that the uptake of Mg resembles that of Ca and that of Al that of Fe. With the wood ash application, the pH increased from 3.2 to 4.8, the base saturation from 30% to 86%, the molar basic cations/Al ratio (BC/Al) of the soil solution from 1.5 to 5.5, and the molar Ca/Al ratio of the fine roots from 1.3 to 3.7. Overall, all below-ground indicators of soil acidification responded positively to the wood ash application within two years. Nitrate concentrations increased only slightly in the soil solution at a soil depth of 75-80 cm, and no signs of increased heavy metal concentrations in the soils or in the fine roots were apparent. This suggests that the recycling of wood ash could be an integral part of sustainable forest management because it closes the nutrient cycle and reverses soil acidificatio

Osteosynthese distaler Radiusfrakturen mit der AO/ASIF Titan-Pi-Platte

Zusammenfassung: Die AO/ASIF Titan-Pi-Platte wurde entwickelt, um eine optimale Versorgung distaler, intraartikulärer und instabiler Radiusfrakturen zu gewährleisten. Dies soll durch eine optimale Anpassung an die Anatomie sowie durch Winkelstabilität und flachem Design erfolgen. Ziel der vorliegenden retrospektiven Fallkontrollstudie war es, die objektiven und subjektiven Resultate anhand einer konsekutiven Reihe von 61Patienten mindestens 12Monate (12-29Monate) postoperativ mittels Befragung, klinischer Untersuchung und konventioneller radiologischer Bildgebung zu erheben. Nach Klassifikation der AO handelte es sich um 3A2-, 23A3-, 1B1-, 12C1- und 22C2-Frakturen. Die Resultate zeigen insgesamt ein gutes bis sehr gutes Resultat bezüglich des subjektiven Befindens. Die Messungen des Bewegungsumfangs ergaben durchschnittlich über 80% im Vergleich zur Gegenseite. Die klinische Prüfung der Extensorensehnen ergab keine Rupturen und 18% Irritationen. Das Kollektiv mit Osteosynthesematerialentfernung zeigte einen signifikant größeren Bewegungsumfang der Extension und Ulnarabduktion, eine höhere Kraft sowie nur 3,8% Sehnenirritationen. Mit der Pi-Platte lassen sich gute subjektive und objektive Resultate erreichen. Aufgrund der signifikant besseren Beweglichkeit und höheren Kraft sowie der geringeren Rate an Sehnenirritationen nach Entfernung der Platte sollte die Indikation zur Osteosynthesematerialentfernung großzügig gestellt werde

Seniorenläufer werden schneller und gewinnen Ultramarathons

Quintessenz • Seniorensportler (Läufer über 35 Jahre) dominieren Ultramarathons, also Läufe, die länger sind als die klassische Marathondistanz von 42,195 km. • Aus physiologischer Sicht wird mit ca. 35 Jahren der Leistungszenit im Langstrecken-Laufsport überschritten. • Das Alter der Spitzenleistung im Ultralaufen steigt mit zunehmender Distanz und/oder der Dauer eines Ultramarathons. • Lebenslanger Ausdauersport vermindert die altersbedingte Abnahme der maximalen Sauerstoffaufnahme um ca. 50%. • Eine Abnahme der Muskelmasse ist kein unabwendbares Schicksal, denn regelmässiges Training lässt den altersbedingten jährlichen Abbau auf bis zu 0,5% schrumpfen

Treatment of the Open Abdomen with the Commercially Available Vacuum-Assisted Closure System in Patients with Abdominal Sepsis: Low Primary Closure Rate

Background: Abdominal Vacuum-Assisted Closure (V.A.C.) systems for treatment of open abdomens have been predominantly used for trauma patients with a high primary fascial closure rate. Use of the V.A.C. technique in abdominal sepsis is less well established. Methods: All patients with abdominal sepsis and treatment with the abdominal V.A.C. system between 2004 and 2007 were prospectively assessed. End points were fascial closure, V.A.C.-related morbidity, and quality of life score (SF-36) at follow-up. Results: Thirty patients with abdominal sepsis were included in the study. Primary fascial closure was feasible in 10, partial closure in 4, and no closure in 16 patients. Median number of V.A.C. changes was 3 (range, 1-10). Nine patients died. V.A.C.-related morbidity was as follows: two fistulas, three fascial edge necroses, one skin blister, and four prolapses of small bowel between the fascia and foam. Univariate analysis showed no variables influencing primary closure rate or V.A.C.-related morbidity. Mortality was significantly influenced by age (P<0.001), respiratory failure (P=0.01), and pneumonia (P=0.03). At follow-up, V.A.C. patients scored lower in the physical health scores and similar in the mental health scores compared with the normal population. Conclusions: Treatment of the open abdomen in patients with abdominal sepsis with the abdominal V.A.C. system is safe with good long-term quality of life. Primary closure rate in these patients is substantially lower than in trauma patients. Stepwise closure of the fascia during V.A.C. changes should be attempted to avoid additional lateral retraction of fascial edges. V.A.C.-related complications may be avoided with careful surgical techniqu

Holographic Superconductors with Lifshitz Scaling

Black holes in asymptotically Lifshitz spacetime provide a window onto finite temperature effects in strongly coupled Lifshitz models. We add a Maxwell gauge field and charged matter to a recently proposed gravity dual of 2+1 dimensional Lifshitz theory. This gives rise to charged black holes with scalar hair, which correspond to the superconducting phase of holographic superconductors with z > 1 Lifshitz scaling. Along the way we analyze the global geometry of static, asymptotically Lifshitz black holes at arbitrary critical exponent z > 1. In all known exact solutions there is a null curvature singularity in the black hole region, and, by a general argument, the same applies to generic Lifshitz black holes.Comment: 23 pages, 4 figures; v2: added references; v3: matches published versio

Quantifying cup overhang after total hip arthroplasty: standardized measurement using reformatted computed tomography and association of overhang distance with iliopsoas impingement

OBJECTIVES Currently, there is no standardized measurement method for evaluating cup overhang (CO) in patients undergoing total hip arthroplasty (THA). We propose a novel, standardized method of measuring overhang distance in patients following primary total hip arthroplasty (THA) on computed tomography (CT) images after multiplanar reformation and compare it to a previously proposed measurement method on sagittal CT images. MATERIALS AND METHODS This retrospective study included patients who underwent primary THA with an anterior approach. Patients with cup overhang (CO) and iliopsoas impingement (IPI) were identified by clinical and imaging data. Uncorrected overhang distance (OD$_{u}$) was evaluated on orthogonal sagittal CT images while corrected overhang distance (OD$_{c}$) was evaluated on reformatted sagittal CT images corrected for pelvic rotation and aligned with the plane of the cup face. RESULTS Out of 220 patients with THA, 23 patients (10.4%) with CO and 16 patients (7.3%) with IPI were identified. CO was significantly associated to IPI (p < 0.001). The inter- and intrareader agreement was almost perfect for OD$_{c}$ (κ = 0.822, κ = 0.850), whereas it was fair and moderate for OD$_{u}$ (κ = 0.391, κ = 0.455), respectively. The discriminative ability of OD$_{c}$ was excellent (area under the curve (AUC) = 0.909 (95% confidence interval (CI) 0.784-1.000)) in the receiver operating characteristic analysis. Conversely, AUC for OD$_{u}$ was poor, measuring 0.677 (95% CI 0.433-0.921). CONCLUSION We implemented a novel measurement method for CT images reformatted at the plane of the cup face to assess overhang distance in patients with CO following THA. CLINICAL RELEVANCE STATEMENT While further validation is necessary, the proposed method is characterized by its high reproducibility and might be used to predict the occurrence of iliopsoas impingement in patients with cup overhang following total hip arthroplasty. KEY POINTS • A novel, standardized method of measuring cup overhang distance in patients following primary total hip arthroplasty on CT images is proposed. • Cup overhang was associated to iliopsoas impingement. The proposed method was reproducible and showed excellent prediction of iliopsoas impingement in patients with cup overhang. • This method can be implemented in clinical practice when assessing CT images of patients with cup overhang for iliopsoas impingement

The evolution of pebble size and shape in space and time

We propose a mathematical model which suggests that the two main geological observations about shingle beaches, i.e. the emergence of predominant pebble size ratios and strong segregation by size are interrelated. Our model is a based on a system of ODEs called the box equations, describing the evolution of pebble ratios. We derive these ODEs as a heuristic approximation of Bloore's PDE describing collisional abrasion. While representing a radical simplification of the latter, our system admits the inclusion of additional terms related to frictional abrasion. We show that nontrivial attractors (corresponding to predominant pebble size ratios) only exist in the presence of friction. By interpreting our equations as a Markov process, we illustrate by direct simulation that these attractors may only stabilized by the ongoing segregation process.Comment: 22 pages, 8 figure