bluuebunny/crossref_metadata_2025 huggingface dataset:
Screening for acetylcholinesterase inhibitory activity in plant extracts from Argentina
Authors: Carpinella María C. , Andrione Diego G. , Ruiz Gustavo , Palacios Sara M.
Published: July 2009

Plants are a potential source of bioactive compounds and offer a promising strategy for the treatment of neurological disorders such as Alzheimer's disease.

The inhibitory effect of 73 native and naturalized plants collected from the central region of Argentina on acetylcholinesterase (AChE) was tested using microplate and TLC assays after solvent fractionation of complete ethanol extracts obtained from the plants.

Organic fractions obtained from extracts ofAchyrocline tomentosa(Asteraceae),Eupatorium viscidum(Asteraceae),Ruprechtia apetala(Polygonaceae)Trichocline reptans(Asteraceae) andZanthoxylum coco(Rutaceae) presented strong inhibition of AChE (higher than 80%) at 1 mg/mL, withR. apetalaandT. reptansbeing the most potent, showing complete inhibition of the enzyme. Their IC50values were 0.0779 and 0.1118 mg/mL, respectively. Aqueous fractions did not show any inhibitory activity on the enzyme. These results suggest that the most effective extracts deserve further investigation with the aim of obtaining new molecules for the treatment of neurodegenerative disorders. Copyright © 2009 John Wiley & Sons, Ltd.
Screening of Kit inhibitors: suppression of Kit signaling and melanogenesis by emodin
Authors: Lee Seong Jin , Jeong Daeyoung , Park Woo‐Kyu , Kong Jae Yang , Choi Gildon , Kim Hojeong , Kang Sangjin , Cho Heeyeong
Published: July 2009

In search of novel antipigmentation agents, a set of 3,840 compounds with natural‐like synthetic or natural origin were screened against Kit (stem cell factor receptor). Emodin from the seed of Cassia tora and baicalin from Scutellariae radix showed potent inhibitory effects (IC50 = 4.9 and 9.0 mm, respectively) on the phosphorylation of Kit. Emodin also blocked other receptor tyrosine kinase activities, such as epithelial growth factor receptor (EGFR), vascular endothelial growth factor receptor 2 (VEGFR‐2), fibroblast growth factor receptor 1 (FGFR‐1), platelet‐derived growth factor receptor b (PDGFR‐b). In contrast to emodin, aloe‐emodin did not inhibit Kit activity at all. Emodin also blocked the cellular kinase activities of Kit and its down‐stream p44/42 mitogen activated protein kinase (MAPK) in MO7e cells and human primary melanocytes. Emodin strongly suppressed the melanin synthesis triggered by stem cell factor (SCF) treatment. Also, emodin showed almost no toxicity up to 10 mm on cultured melanocytes as reported previously by other researchers. The results indicate that emodin is a good candidate for the development of antipigmentation agents since it can radically block the differentiation and proliferation of pigment cells by reducing Kit signaling. Copyright © 2009 John Wiley & Sons, Ltd.
Ice and water content of stratiform mixed‐phase cloud
Authors: Vidaurre German , Hallett John
Published: July 2009

Spatial characterization and probability distribution of particles in stratiform mixed‐phase clouds in the temperature range 5 to −45 °C were investigated based on 81 hours of flight on the NCAR C‐130 during the Alliance Icing Research Study II. Cloud particles were video‐recorded impacting on the optical window of a cloudscope, and Liquid Water Content (LWC) and Ice Water Content (IWC) derived from measurements of the power to evaporate particles of different size, shape and density collected by the T probe constant temperature sensors. Data were recorded at 1 Hz for a resolution of 130 m. Transitions between liquid, glaciated and mixed‐phase regions were sharp; frequent supercooled liquid regions lasted less than 2 seconds (<260 m), while less frequent mixed‐phase and glaciated regions persisted between 2 and 300 seconds (0.26 to 39 km) along the aircraft track. LWC, IWC and Total Water Content (TWC) were measured in concentrations up to 1.25, 0.45 and 1.25 g m−3 with an uncertainty of ∼0.02 g m−3. The IWC/TWC ratio showed two maxima at mostly liquid (<0.1) and mostly ice (>0.9); mixed‐phase corresponded to about 40% of the measurements. The large T probe showed mixed‐phase clouds with ice fraction less than half at temperatures below −20 °C, while the small T probe measured higher ice proportion, suggesting that ice was present in the form of preferentially collected small particles. At high temperatures (>−15 °C) ice and water were measured in concentrations up to 0.2 and 0.6 g m−3 respectively; at temperatures below −20 °C they were both measured in concentrations up to 0.3 g m−3. Copyright © 2009 Royal Meteorological Society
The characteristics of Hessian singular vectors using an advanced data assimilation scheme
Authors: Lawrence A. R. , Leutbecher M. , Palmer T. N.
Published: July 2009

Initial condition uncertainty is a significant source of forecast error in numerical weather prediction. Singular vectors of the tangent linear propagator can identify directions in phase‐space where initial errors are likely to make the largest contribution to forecast‐error variance. The physical characteristics of these singular vectors depend on the choice of initial‐time metric used to represent analysis‐error covariances: the total‐energy norm serves as a proxy to the analysis‐error covariance matrix, whereas the Hessian of the cost function of a 4D‐Var assimilation scheme represents a more sophisticated estimate of the analysis‐error covariances, consistent with observation and background‐error covariances used in the 4D‐Var scheme.

This study examines and compares the structure of singular vectors computed with the European Centre for Medium‐Range Weather Forecasts (ECMWF) Integrated Forecasting System using these two types of initial metrics. Unlike earlier studies that use background errors derived from lagged forecast differences (the NMC method), the background‐error covariance matrix in the Hessian metric is based on statistics from an ensemble of 4D‐Vars using perturbed observations, which produces tighter correlations of background‐error statistics than in previous formulations. In light of these new background‐error statistics, this article re‐examines the properties of Hessian singular vectors (and their relationship to total‐energy singular vectors) using cases from different periods between 2003 and 2005. Energy profiles and wavenumber spectra reveal that the total‐energy singular vectors are similar to Hessian singular vectors that use all observation types in the operational 4D‐Var assimilation. This is in contrast to the structure of Hessian singular vectors without observations. Increasing the observation density tends to reduce the spatial scale of the Hessian singular vectors. Copyright © 2009 Royal Meteorological Society
Vom Entwurf zur Umsetzung der Stahlkonstruktionen für das Bauwerk Neue Mitte Lehen in Salzburg
Authors: Olipitz Michael , Holzleithner Regina
Published: July 2009

Der neu errichtete, multifunktionale Kommunalbau Neue Mitte Lehen ist ein Gebäudekomplex mit Signalwirkung für die gesamte Stadt Salzburg und trägt wesentlich zur Belebung dieses Stadtteiles bei. Die Gebäudeform mit den weit auskragenden Gebäudeteilen Bibliotheksgeschoss und Panoramabar erfordert den Einsatz hochtechnologischer Werkstoffe, wie sie der Baustoff Stahl bestens erfüllen kann. Der Entwicklungsprozess vom Entwurfsgedanken bis zur Umsetzung erfordert ein Planungsteam, das die Herausforderungen besonders in der Phase der Umsetzung bewältigen kann. Im folgenden Aufsatz sind die Aspekte der Stahlkonstruktion vom Entwurf bis zur Montage beschrieben. Immer wo die Gewerke des Beton‐ und Stahlbaus abgestimmt aufeinander arbeiten, ist auf die Schnittstellenproblematik zu achten. Bei diesem Bauvorhaben wurde diese Aufgabe durch die Beteiligten vorbildlich gelöst.

From the design up to the realization of the steel constructions for the building Neue Mitte Lehen in Salzburg.

Salzburg's newest landmark, the recently completed public building Neue Mitte Lehen, accounts with its utilizations for public life within the quarter. The form with its cantilevering parts makes the use of demanding materials like steel necessary. The design process from first sketches to construction requires a team that masters the challenges especially during the building process. The following text describes aspects of the steel construction from design to erection. Special attendance must be paid to the coordination of the crafts of concrete and steel construction. However this task was perfectly solved within this building project.
Netzgenerierung von Netzwerkbogenbrücken
Authors: Schanack Frank , Brunn Benjamin
Published: July 2009

Nachdem der Netzwerkbogen über Jahrzehnte nahezu unbeachtet blieb, bildet er heute einen immer beliebteren Bestandteil des Brückenbaurepertoires. Seine statischen Vorteile überzeugen mehr und mehr Brückenbauverwaltungen, so dass in aller Welt zahlreiche neue Netzwerkbogenbrücken entstehen. Umso interessanter werden Hinweise für einen einfachen, raschen und nahezu optimalen Vorentwurf, gerade für “Einsteiger” auf dem Gebiet. Die größte Schwierigkeit beim Entwurf ist die Hängeranordnung, die durch Variablen wie Anzahl der Hängersets, Anzahl der Hänger pro Set sowie Neigungswinkel und Position jedes Hängers beschrieben wird. Anstatt der sehr aufwendigen Bestimmung von Lage und Neigung jedes einzelnen Hängers empfiehlt sich die Verwendung von Generierungsvorschriften für den Entwurf des gesamten Hängernetzes. Die gängigsten Generierungsverfahren Rautennetz, konstante Winkeländerung, konstanter Abstand sowie radiale Hängeranordnung werden erläutert und beurteilt. Letztendlich kristallisiert sich die radiale Hängeranordnung als eine Methode heraus, die auf sehr einfache und schnelle Art und Weise zu einer statisch sehr vorteilhaften Hängeranordnung führt.

Generation of network arch hanger arrangements.

After the network arch remained almost completely unnoticed for decades, it now constitutes an increasingly popular element of today's bridge construction repertory. Its structural advantages convince more and more bridge authorities, so that numerous new network arches are built all over the world. This circumstance calls for straight‐forward and quick ways to nearly optimal preliminary designs, especially for engineers who are new to this type of bridge. The biggest design challenge is the hanger arrangement that depends on the number of hanger sets, number of hangers per set as well as the hanger slope and hanger position. Instead of determining the geometry of each hanger individually, it is recommended to use general generation methods. The most common generation methods rhombus net, constant angle change, constant distance as well as the radial arrangement are discussed and evaluated. Ultimately, the radial arrangement turns out to be a very easy and fast method to obtain structurally very advantageous hanger arrangements.
Die Erhöhung des Nutzerkomforts von Fußgängerbrücken mit Massendämpfern am Beispiel des August‐Wilhelm‐Stegs in Oranienburg
Authors: Kuhlmann Wolfram , Butz Christiane
Published: July 2009

Aufgrund ihrer schlanken Bauweise gelten viele Fußgängerbrücken bei personeninduzierten Belastungen als schwingungsanfällig. Die eventuelle Ausstattung einer Brücke mit zusätzlichen Dämpfungsmaßnahmen sollte bereits in der Planungsphase berücksichtigt werden, damit bei Gewissheit, dass Maßnahmen notwendig sind, die Fertigstellung und Eröffnung der Brücke nicht verzögert wird.

Im vorliegenden Beitrag wird am Beispiel des August‐Wilhelm‐Stegs in Oranienburg das Vorgehen zwischen Erkennen einer möglichen Schwingungsanfälligkeit, Prüfung der Erforderlichkeit schwingungsdämpfender Maßnahmen, Auslegung und Einbau sowie Überprüfung der Wirksamkeit erläutert. Dabei werden insbesondere die praktischen Aspekte bei der Auslegung der Massendämpfer erläutert.

The increasing comfort of footbridges with mass dampers is exemplary shown with the August‐Wilhelm‐Steg in Oranienburg, Germany.

Many footbridges are susceptible to pedestrian induced vibrations due to their slender design. Hence, an equipment with additional damping devices on demand should be considered already in the preliminary design phase to avoid unnecessary delays of the erection and opening, if the damping devices are required.

In this article the procedure of identifying a potential vibration susceptibility, checking the necessity of damping devices, design and installation as well as checking the working efficiency of them are explained using the example of the August‐Wilhelm‐Steg in Oranienburg. Particular emphasis is laid on the practical aspects when designing tuned mass dampers.
Ein elasto‐plastisches Materialmodell zur realistischen Berechnung der Verformungen mechanisch überhöhter Stahl‐ und Verbundträger
Authors: Böhme Frank , Nelke Harald , Lange Jörg
Published: July 2009

Zur anteiligen Kompensation der Verformungen von Stahl‐ und Verbundträgern werden diese häufig überhöht eingebaut. Wird die Überhöhung durch eine mechanische Beanspruchung (Boxen) aufgebracht, so besitzt der Stahlträger bereits im Einbauzustand plastische Dehnungen. Wie von Grages in [3] gezeigt, führt dies bei der Rückbelastung zu einer Abnahme der Steifigkeit. Dieses Phänomen ist auch als Bauschinger‐Effekt [2] bekannt und kann bei praktischen Verformungsberechnungen zu einer Unterschätzung der tatsächlich auftretenden Deformationen führen. In dem aktuellen Aufsatz wird ein ratenunabhängiges elasto‐plastisches Materialmodell mit linearer und nichtlinearer isotroper sowie nichtlinearer kinematischer Verfestigung vorgestellt, welches eine realistische Abschätzung der Verformungen erlaubt. Das gezeigte Materialmodell ist durch die geringe Anzahl an Eingangsparametern sehr einfach anwendbar. Eine gezielte Anpassung der einzelnen Parameter wird in anschaulicher Form dargestellt. Die Qualität des Modells wird anhand der Nachrechnung von in [3] durchgeführten Versuchen überprüft.

An elasto‐plastic material model for realistic calculation of the deformations of mechanical cambered steel‐ and composite girders.

Steel and composite girders are often cambered before they are embedded into structures to compensate deflections. In case of a mechanical pre‐deformation via a hydraulic press the steel girder contains plastic strains before assembly. As shown by Grages [3] this leads to a reduction of stiffness and strength during reverse loading. This phenomenon is also known as the Bauschinger‐Effect [2] and may lead to an underestimation of the real deformation during a structural analysis. In this paper a rate‐independent elastoplastic material model with linear and nonlinear isotropic as well as nonlinear kinematic hardening is introduced which allows a realistic estimation of deformations. The material model presented can be easily applied due to its low number of parameters. A straightforward algorithm to adjust the single parameters is described. The quality of the model is verified by a recalculation of experimental data from [3].
Physicochemical Properties of Non‐thermally Cross‐linked Corn Starch with Phosphorus Oxychloride using Ultra High Pressure (UHP)
Authors: Hwang Duck‐Ki , Kim Byung‐Yong , Baik Moo‐Yeol
Published: July 2009

Corn starch (20%, w/w) was non‐thermally and conventionally cross‐linked with phosphorus oxychloride (POCl3; 0.01, 0.05, or 0.1%, based on dry weight of starch) at 400 MPa for 5, 15 and 30 min and at 45°C for 2 h, respectively. Swelling power and solubility of both non‐thermally and conventionally cross‐linked corn starches were relatively lower than those of native corn starch. The pressure holding time did not affect the solubility and swelling power of non‐thermally cross‐linked corn starches. X‐ray diffraction patterns and relative crystallinity were not significantly altered by both conventional and non‐thermal cross‐linking. DSC thermal characteristics of both non‐thermally and conventionally cross‐linked corn starches were not significantly changed indicating that the double helical structure of amylopectin was not influenced by both conventional and non‐thermal cross‐linking reactions. Both non‐thermal and conventional cross‐linking greatly affected the Rapid Visco Analyser (RVA) pasting properties, such as increase in pasting temperature and decrease in peak viscosity compared to native starch. This result suggests that in case of cross‐linking using POCl3, both non‐thermal and conventional methods result in similar physicochemical properties and non‐thermal cross‐linking with POCl3 can reduce the reaction time from 2 h to 15 min. This work shows the potential and possibility of non‐thermal starch modification and provides the basic and scientific information on the physicochemical properties of non‐thermally cross‐linked corn starches with phosphorus oxychloride using UHP.
Determination of Optimum Conditions for Enzymatic Debranching of Cassava Starch and Synthesis of Resistant Starch Type III using Central Composite Rotatable Design
Authors: Mutungi Christopher , Onyango Calvin , Jaros Doris , Henle Thomas , Rohm Harald
Published: July 2009

Cassava starch was debranched by treatment with isoamylase and pullulanase and the yield of resistant starch type III (RS III) optimized with respect to starch solids concentration (7.5‐15%, w/v), incubation time (8‐24 h) and enzyme concentration using central composite rotatable design. Higher concentrations of pullulanase (10‐35 U/g starch) compared to isoamylase (30–90 mU/g starch) were required to give a similar degree of starch hydrolysis within the experimental domain. A clear debranching end‐point was identifiable by following the reducing value, blue value and β‐hydrolysis limit of cassava starches debranched using isoamylase. It was difficult to define a debranching endpoint of pullulanase treatment by these parameters due to contaminating α‐D‐(1→4) activity. The yield of RS III was significantly higher in isoamylolysates and increased steadily with increasing degree of hydrolysis to peak at 57.3%. Purification of the debranched material further increased the RS III yield to 64.1%. Prolonged (24 h) hydrolysis of cassava starch with high concentration of pullulanase (35 U/g) gave lower RS III contents in the purified (34.2%) and unpurified (36.2%) hydrolysates compared to 49.5 and 62.4%, respectively, at moderate pullulanase concentration (22.5 U/g) and incubation time (16 h).
Resistant Starch Content and Structural Changes in Maize (Zea mays) Tortillas During Storage
Authors: García‐Rosas Marina , Bello‐Pérez Arturo , Yee‐Madeira Hernani , Ramos Gonzalo , Flores‐Morales Areli , Mora‐Escobedo Rosalva
Published: July 2009

Storage of maize products such as tortillas may cause starch retrogradation and lead to resistant starch (RS) formation. This study was carried out to determine if storage of maize tortillas under refrigerated conditions enhanced RS content and/or modified RS structure. Improved Costeño variety maize grain was nixtamalized and processed into tortillas which were stored for five and ten days at 5°C. Total resistant starch (TRS) and retrograded resistant starch (RRS or RS3) contents were determined on raw and nixtamalized maize grain and tortillas stored for zero, five and ten days. Differential scanning calorimetry (DSC), X‐ray diffraction (XRD) and near‐infrared (NIR) spectroscopy were use to evaluate structural changes in retrograded resistant starch isolated from each sample type. Total starch content was 67 ± 1.5% for all samples, TRS ranged from 3.3% in the raw grain at 7.2% in tortillas stored for ten days, while RRS starch content ranged from 0% in the raw grain to 3.2% in tortillas stored for ten days. DSC showed endothermic transitions corresponding to amylopectin and amylose retrogradation, at 31.9 and 139.7°C in RRS from tortillas stored for five days, and at 47.9 and 146°C in RRS from tortillas stored for ten days. These values agreed with the higher total RS content recorded after prolonged storage. XRD revealed a starch crystallinity of 13.7% in tortillas stored for five days and 15.3% in those stored for ten days. NIR spectroscopy analysis showed evidence of structural changes in polymeric order that were more pronounced in RRS of tortillas stored for ten days, due to increase in crystalline region.
Adding a single CA 125 measurement to ultrasound imaging performed by an experienced examiner does not improve preoperative discrimination between benign and malignant adnexal masses
Authors: Valentin L. , Jurkovic D. , Van Calster B. , Testa A. , Van Holsbeke C. , Bourne T. , Vergote I. , Van Huffel S. , Timmerman D.
Published: July 2009

Objectives

To determine whether CA 125 measurement is superior to ultrasound imaging performed by an experienced examiner for discriminating between benign and malignant adnexal lesions, and to determine whether adding CA 125 to ultrasound examination improves diagnostic performance.

Methods

This is a prospective multicenter study (International Ovarian Tumor Analysis (IOTA) study) conducted in nine European ultrasound centers in university hospitals. Of 1149 patients with an adnexal mass examined in the IOTA study, 83 were excluded. Of the remaining 1066 patients, 809 had CA 125 results available and were included. The patients underwent preoperative serum CA 125 measurements and transvaginal ultrasound examination by an experienced ultrasound examiner blinded to CA 125 values. The examiner classified each mass as certainly or probably benign, difficult to classify, or probably or certainly malignant. The outcome measure was the sensitivity and specificity with regard to malignancy of CA 125, ultrasound imaging and their combined use, the ‘gold standard’ being the histological diagnosis of the adnexal mass removed surgically within 120 days after the ultrasound examination.

Results

There were 242 (30%) malignancies. For 534 tumors judged to be certainly benign or certainly malignant by the ultrasound examiner the sensitivity and specificity of ultrasound examination and CA 125 (≥35 U/mL indicating malignancy) were 97% vs. 86% (95% CI of difference, 4.7–17.2) and 99% vs. 79% (95% CI of difference, 15.7–24.2); for 209 tumors judged probably benign or probably malignant, sensitivity and specificity were 81% vs. 57% (95% CI of difference, 12.3–36.0) and 91% vs. 74% (95% CI of difference, 8.5–25.7); for 66 tumors that were difficult to classify, sensitivity and specificity were 57% vs. 39% (95% CI of difference, −9.7 to 41.1) and 74% vs. 67% (95% CI of difference, −14.6 to 27.7). Diagnostic performance deteriorated when CA 125 was used as a second‐stage test after ultrasound examination.

Conclusions

Specialist ultrasound examination is superior to CA 125 for preoperative discrimination between benign and malignant adnexal masses, irrespective of the diagnostic confidence of the ultrasound examiner; adding CA 125 to ultrasound does not improve diagnostic performance. Our results indicate that greater investment in education and training in gynecological ultrasound imaging would be of value. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
A comparison of smart rotor control approaches using trailing edge flaps and individual pitch control
Authors: Lackner Matthew A. , van Kuik Gijs
Published: July 2009

Modern wind turbines are steadily increasing in size, with recent models boasting rotor diameters greater than 120 m. Wind turbines are subjected to significant and rapid fluctuating loads, which arise from a variety of sources including turbulence, tower shadow, wind shear and yawed flow. Reducing the loads experienced by the rotor blades can lower the cost of energy of wind turbines. ‘Smart rotor control’ concepts have emerged as a solution to reduce fatigue loads on wind turbines. In this approach, aerodynamic load control devices are distributed along the span of the blade, and through a combination of sensing, control and actuation, these devices dynamically control the blade loads.

This research investigates the load reduction capabilities of smart rotor control devices, namely trailing edge flaps (TEFs), in the operation of a 5 MW wind turbine. A feedback control approach is implemented for load reduction, which utilizes a multiblade coordinate transformation. Single input–single output control techniques are employed to determine the appropriate response of the TEFs based on the blade loads. The use of TEFs and this control approach is shown to effectively reduce the fatigue loads on the blades, relative to a baseline controller. The load reduction potential is also compared to an alternative individual pitch control (IPC) approach, in the time and frequency domain. The effects on the pitch and power systems are briefly evaluated, and the limitations of the analysis are assessed. Finally, a combined approach that uses both TEFs and IPC is evaluated. Copyright © 2009 John Wiley & Sons, Ltd.
Insulin‐resistant hyperglycaemia complicating neonatal onset of methylmalonic and propionic acidaemias
Authors: Filippi L. , Gozzini E. , Cavicchi C. , Morrone A. , Fiorini P. , Donzelli G. , Malvagia S. , la Marca G.
Published: July 2009

Background: Insulin‐resistant hyperglycaemia may occasionally complicate the clinical course of organic acidaemias. Study Design: Clinical observation. Results: Two term infants, one suffering from acute early‐onset methylmalonic acidaemia, the other suffering from acute early‐onset propionic acidaemia, presented acutely with dehydration, ketoacidosis, and hyperammonaemia. Urinary organic acid, plasma amino acids, and blood and plasma acylcarnitine analysis allowed the diagnosis of methylmalonic and propionic acidaemias. The detection of the novel c.481G>A (p.Gly161Arg) and the known c.655A>T (p.Asn219Tyr) MUT gene mutations identified the first patient as affected by methylmalonic acidaemia mut type. The high increase of propionylcarnitine after carnitine administration in both patients suggested a greatly elevated metabolic intoxication. Both newborns showed insulin‐resistant hyperglycaemia. Patient 1 died, but patient 2, after a strong reduction of glucose administration, survived. To our knowledge, this is the only patient with this complication who survived. Conclusion: Insulin‐resistant hyperglycaemia complicating neonatal onset of methylmalonic and propionic acidaemias is probably a marker of a serious disease. One patient with this complication survived after a strong reduction of glucose administration. Even if this is probably only a partial intervention, we hypothesize that in this situation a reduction of glucose administration can reduce almost the risk of persistent hyperglycaemia. Further studies are required to confirm our hypothesis.
Impact of altitudinal gradients on energetics and efficiencies of N2‐fixation in alder–cardamom agroforestry systems of the eastern Himalayas
Authors: Sharma G. , Sharma R. , Sharma E.
Published: July 2009

The impact of altitudinal gradients on the performance of alder–cardamom agroforestry systems was analyzed on nitrogenase activity, N2‐fixation efficiency, and stand energetics and efficiencies in the eastern Himalayas. Acetylene reduction (AR activity) measurements showed that nitrogenase activity considerably increased with advancing altitudes from 500 to 800 m to a peak at 900–1,200 m. AR activity was fairly high, between 1,300 and 1,700 m, and sharply decreased in the stands between 1,800 and 2,100 m. AR activity increased in the growing season and peaked in the rainy season. This significantly coincided with cardamom flowering during the onset of growing season to full fruiting stage at peak activity period. AR activity was dependent on soil temperature and moisture and showed a positive relationship. Nodule moisture was also a limiting factor for AR activity and showed a positive correlation. Diurnal changes showed a marked variation with highest AR activity between 8 and 12 h. The performance of commercial cardamom crop is dependent on the associated shade trees. Yield potential significantly coincided with the rate of N2‐fixation both at age chronosequence and altitudinal gradients. The management comprises growing large number of alder until 10 years and thinning, and gap filling of cardamom up to 20 years. Such maintenance caused non‐equilibrium conditions that favored systems efficiency and excellent production until 20 years. System efficiency sharply declined at low rates of N2‐fixation, AR activity, root nodule production, and agronomic yield due to the influence of stand age and altitudinal gradients. Agroforestry stands at 900–1,700 m were more energy cost‐effective due to the lower energy required for per‐kg N‐fixation with high N supply (115–155 kg ha−1) confirming functionally efficient than those stands at extreme higher and lower altitudinal ranges. Therefore, replantation of alder and cardamom and phase wise agroforestry rotation after 20 years could be an ecologically and economically sustainable management practice.
Agreement between Initial Classification and Subsequent Reclassification of Fractures of the Distal Radius in a Prospective Cohort Study
Authors: van Leerdam Roderick H. , Souer J. Sebastiaan , Lindenhovius Anneluuk L. C. , Ring David C.
Published: July 2009

We tested the hypothesis that the original surgeon-investigator classification of a fracture of the distal radius in a prospective cohort study would have moderate agreement with the final classification by the team performing final analysis of the data. The initial post-injury radiographs of 621 patients with distal radius fractures from a multicenter international prospective cohort study were classified according to the Comprehensive Classification of Fractures, first by the treating surgeon-investigator and then by a research team analyzing the data. Correspondence between original and revised classification was evaluated using the Kappa statistic at the type, group and subgroup levels. The agreement between initial and revised classifications decreased from Type (moderate; Ktype=0.60), to Group (moderate; Kgroup=0.41), to Subgroup (fair; Ksubgroup= 0.33) classifications (all p<0.05). There was only moderate agreement in the classification of fractures of the distal radius between surgeon-investigators and final evaluators in a prospective multicenter cohort study. Such variations might influence interpretation and comparability of the data. The lack of a reference standard for classification complicates efforts to lessen variability and improve consensus.
How does imagery in interactive consumption lead to false memory? A reconstructive memory perspective
Authors: Lakshmanan Arun , Krishnan H. Shanker
Published: July 2009

Consumers are often exposed to information that may contradict their consumption experience, leading to “false memory” for aspects of the consumption. We develop a theory suggesting why false memory may be heightened due to imagery processing. We subject this theory to a rigorous test in three experiments. We find that post‐consumption imagery makes it more difficult to discern between consumption and misleading information thereby boosting false recall. Yet, imagery that is more consumption‐based helps reduce consumers' susceptibility to false memory. Consistent with this notion, we explicate the role that attention plays at different stages of consumption in affecting false memory.
Entscheidungsunterstützung durch wissenschaftliche Evidenz
Authors: Koch Klaus , Sawicki Peter T.
Published: July 2009

Einleitung

Die Wahrnehmung, was mit wissenschaftlicher Evidenz gemeint ist, hat sich in den letzten Jahren deutlich verändert. Der Wechsel der Perspektive ist eng mit dem Begriff evidenzbasierte Medizin verbunden. Gemeint ist damit eine medizinische Betreuung von Patienten, die sich nicht alleine auf Meinungen und Übereinkünfte stützt, sondern wissenschaftliche Nachweise einbezieht, die mit möglichst zuverlässigen Methoden erhoben wurden. In diesem Zusammenhang ist eine bewusste Beschränkung auf „Nützliches“ zwar eine Kernnotwendigkeit eines solidarischen Gesundheitswesens, sie muss aber sorgfältig (und rechtssicher) begründet sein, da sie massive Auswirkungen auf wirtschaftliche Interessen und Märkte haben kann.
CORPORATE RESPONSIBILITY AND JUDGMENT AGGREGATION
Authors: Hindriks Frank
Published: July 2009

Paradoxical results concerning judgment aggregation have recently been invoked to defend the thesis that a corporate agent can be morally responsible for a decision without any of its individual members bearing such responsibility. I contend that the arguments offered for this irreducibility thesis are inconclusive. They do not pay enough attention to how we evaluate individual moral responsibility, in particular not to the role that a flawed assessment of the normative reasons that bear on the issue to be decided on play in this context. I go on to propose a method for distributing corporate responsibility to individual members within the judgment aggregation framework.
Chevalley's theorem in class Cr
Authors: Barbançon Gérard P.
Published: July 2009

Let W be a finite reflection group acting orthogonally on ℝn, P be the Chevalley polynomial mapping determined by an integrity basis of the algebra of W-invariant polynomials, and h be the highest degree of the coordinate polynomials in P. Let r be a positive integer and [r/h] be the integer part of r/h. There exists a linear mapping $\mathcal{C}^r(\mathbb{R}^n)^W\ni f\mapsto F\in\mathcal{C}^{[r/h]}(\mathbb{R}^n)$ such that f = F ∘ P, which is continuous for the natural Fréchet topologies. A general counter-example shows that this result is the best possible. The proof uses techniques of division by linear forms and a study of compensation phenomena. An extension to P−1(ℝn) of invariant formally holomorphic regular fields is needed.
The Littlewood—Paley—Rubio de Francia property of a Banach space for the case of equal intervals
Authors: Hytönen T. P. , Torrea J. L. , Yakubovich D. V.
Published: July 2009

Let X be a Banach space. It is proved that an analogue of the Rubio de Francia square function estimate for partial sums of the Fourier series of X-valued functions holds true for all disjoint collections of subintervals of the set of integers of equal length and for all exponents p ≥ 2 if and only if the space X is a UMD space of type 2. The same criterion is obtained for the case of subintervals of the real line and Fourier integrals instead of Fourier series.
Weak-type inequalities and convergence of the ergodic averages in variable Lebesgue spaces with weights
Authors: Cañestro M. Isabel Aguilar , Salvador Pedro Ortega
Published: July 2009

We characterize the weighted weak-type inequalities with variable exponents for the maximal operator associated with an ergodic, invertible, measure-preserving transformation and prove the almost everywhere convergence of the ergodic averages for all functions in a variable Lebesgue space with a weight verifying a suitable condition.
Infinite-order laminates in a model in crystal plasticity
Authors: Albin Nathan , Conti Sergio , Dolzmann Georg
Published: July 2009

We consider a geometrically nonlinear model for crystal plasticity in two dimensions, with two active slip systems and rigid elasticity. We prove that the rank-1 convex envelope of the condensed energy density is obtained by infinite-order laminates, and express it explicitly via the 2F1 hypergeometric function. We also determine the polyconvex envelope, leading to upper and lower bounds on the quasiconvex envelope. The two bounds differ by less than 2%.
Classes of infinite semipositone systems
Authors: Lee Eun Kyoung , Shivaji R. , Ye Jinglong
Published: July 2009

We analyse the positive solutions to classes of p-Laplacian systems with Dirichlet boundary conditions, in particular, when the reaction terms tend to −∞ at the origin and satisfy a combined sublinear condition at ∞. We use the method of sub- and supersolutions to establish our results.
Existence of multi-bump standing waves with a critical frequency for nonlinear Schrödinger equations with potentials vanishing at infinity
Authors: Kwon Ohsang
Published: July 2009

For a singularly perturbed nonlinear elliptic equation ε2Δu − V(x)u + up = 0, x ∈ ℝN, there are solutions concentrating around critical points of V with different energy scales with respect to small ε > 0. We combine the solutions when $\smash{\liminf_{|x|\to\infty}|x|^2V(x)}>0$.
The M-matrix inverse problem for the Sturm—Liouville equation on graphs
Authors: Currie Sonja , Watson Bruce A.
Published: July 2009

We consider an inverse spectral problem for Sturm–Liouville boundary-value problems on a graph with formally self-adjoint boundary conditions at the nodes, where the given information is the M-matrix. Based on the authors' previous results, using Green's function, we prove that the poles of the M-matrix are at the eigenvalues of the associated boundary-value problem and are simple, located on the real axis, and that the residue at a pole is a negative semi-definite matrix with rank equal to the multiplicity of the eigenvalue. We define the so-called norming constants and relate them to the spectral measure and the M-matrix. This enables us to recover, from the M-matrix, the boundary conditions and the potential, up to a unitary equivalence for co-normal boundary conditions.
Sharp upper and lower bounds for the gamma function
Authors: Alzer Horst
Published: July 2009

We prove that for all x > 0, we have

with the best possible constants α = 0 and $\beta=\tfrac{1}{1620}$.
/u/ fronting and /t/ aspiration in Māori and New Zealand English
Authors: Maclagan Margaret , Watson Catherine I. , Harlow Ray , King Jeanette , Keegan Peter
Published: July 2009

This article examines the relationship between the frontness of /u/ and the aspiration of /t/ in both Māori and New Zealand English (NZE). In both languages, these processes can be observed since the earliest recordings dating from the latter part of the nineteenth century. We report analyses of these developments for three groups of male speakers of Māori spanning the twentieth century. We compare the Māori analyses with analyses of related features of the speakers' English and of the English of monolingual contemporaries. The occurrence of these processes in Māori cannot be seen simply as interference from NZE as the Māori-speaking population became increasingly bilingual. We conclude that it was the arrival of English with its contrast between aspirated and unaspirated plosives, rather than direct borrowing, that was the trigger for the fronting of the hitherto stable back Māori /u/ vowel together with increased aspiration of /t/ before both /i/ and /u/.
Modeling language change: An evaluation of Trudgill's theory of the emergence of New Zealand English
Authors: Baxter Gareth J. , Blythe Richard A. , Croft William , McKane Alan J.
Published: July 2009

Trudgill (2004) proposed that the emergence of New Zealand English, and of isolated new dialects generally, is purely deterministic. It can be explained solely in terms of the frequency of occurrence of particular variants and the frequency of interactions between different speakers in the society. Trudgill's theory is closely related to usage-based models of language, in which frequency plays a role in the representation of linguistic knowledge and in language change. Trudgill's theory also corresponds to a neutral evolution model of language change. We use a mathematical model based on Croft's usage-based evolutionary framework for language change (Baxter, Blythe, Croft, & McKane, 2006), and investigate whether Trudgill's theory is a plausible model of the emergence of new dialects. The results of our modeling indicate that determinism cannot be a sufficient mechanism for the emergence of a new dialect. Our approach illustrates the utility of mathematical modeling of theories and of empirical data for the study of language change.
Ethische Probleme in der klinischen Praxis der evidenzbasierten Medizin
Authors: Rogler  , Fröhlich
Published: July 2009

Ethische Konsequenzen der evidenzbasierten Medizin (EBM) sind bisher selten diskutiert und untersucht. Wird EBM – wie ursprünglich intendiert – als Versuch verstanden, Patienten individuell unter Berücksichtigung der persönlichen Wünsche und des situativen Kontextes auf der Basis der besten zur Verfügung stehenden Einsichten und Kenntnisse zu behandeln, so entspricht dieser Ansatz unmittelbar einem akzeptierten ärztlichen Ethos und scheint daher auch nicht weiter diskussionswürdig zu sein. Zwischen dem theoretischen Konzept und dem praktischen Gebrauch bzw. auch Missbrauch dieses Ansatzes existieren jedoch gravierende Unterschiede, die einer Betrachtung würdig sind. Denn gerade im praktischen Einsatz der EBM ergeben sich eine Reihe ethischer Probleme: EBM wird zunehmend zum Instrument der Ressourcenallokation. Auf der Basis klinischer Untersuchungen für streng definierte Patientengruppen wird der allgemeine Zugang zu medizinischer Versorgung reguliert und limitiert. Die Berufung auf eine externe Evidenz kann zudem in unmittelbarem Widerspruch zum Patientenwillen sein und zu Konflikten bei Therapieentscheidungen führen. Wenn nicht mehr der individuelle Patientenwille im Mittelpunkt der Therapieentscheidungen steht, sondern ein «Gemeinwohl» (also z.B. ein «wirtschaftliches Gesundheitssystem»), wird das Vertrauensverhältnis zwischen Patient und Arzt untergraben. Der utilitaristische und mehr im anglikanischen Gedankengut verbreitete Ansatz des «Primats des Allgemeinwohls» wird durch die aktuelle Interpretation und Anwendung der EBM favorisiert, was im Widerspruch zum Bild des Arztes als Anwalt des individuellen Patienten steht. Dieses Bild des Verhältnisses von Arzt und Patient ist jedoch die Basis des ärztlichen Ethos im mitteleuropäischen Raum.
18-jährige Frau mit zufällig entdecktem Ovarialtumor
Authors: Kunz  , Bannwart  , Gerber  , Dombi
Published: July 2009

Das massive Ödem des Ovars (massive ovarian edema, MOE) ist eine seltene, benigne Erkrankung junger Frauen. Weil präoperativ differentialdiagnostisch meist ein maligner Tumor im Vordergrund steht, besteht das Risiko, dass diese Patientinnen überbehandelt werden. Bei der beschriebenen 18-jährigen Patientin wurde aufgrund präoperativer Daten die klinische Verdachtsdiagnose PCO-Syndrom (Syndrom der polyzystischen Ovarien) gestellt. Im MRI wurde das vergrösserte Ovar als muzinöser Tumor interpretiert. Bei der Laparotomie zeigte sich ein glattwandiger, opalfarbener Ovarialtumor mit Adnextorsion. Die histopathologische Untersuchung des Adnexektomiepräparates ergab die Diagnose eines MOE. Keilexzision, Schnellschnitthistologie, Derotation und Suspension des Ovars wären therapeutisch ausreichend gewesen. Die Übertherapie lässt sich vermeiden, wenn bei jungen Frauen mit vergrössertem Ovar das MOE in die Differentialdiagnose miteinbezogen wird und die charakteristischen Sonographie-, MRI- und Makroskopiebefunde bekannt sind.
Kopfschmerzen und Wortfindungsstörungen bei einem immunsupprimierten Patienten
Authors: Tschudin  , Laifer  , Orasch  , Nüesch
Published: July 2009

Wir berichten über einen 81-jährigen, immunsupprimierten Patienten, welcher sich mit neu aufgetretenen Kopfschmerzen und Wortfindungsstörungen notfallmässig vorstellte. In der MRI-Untersuchung des Neurokraniums zeigte sich eine Raumforderung temporal links mit randständiger Kontrastmittelaufnahme – am ehesten einem Abszess entsprechend. Im weiteren Verlauf konnte in den Blutkulturen Listeria monocytogenes nachgewiesen werden, die Diagnose eines Hirnabszesses verursacht durch Listerien wurde gestellt. Aufgrund der Lokalisation konnte dieser nicht operativ saniert werden, sodass eine protrahierte antibiotische Therapie über 4.5 Monate durchgeführt wurde, nach welcher bildmorphologisch keine Abszesshöhle mehr nachweisbar war. Listeriosen kommen meist bei immunsupprimierten Patienten, älteren Menschen, Neugeborenen und Schwangeren vor. Neben Bakteriämien ohne Fokus ist die ZNS-Invasion mit Meningitis, Meningoenzephalitis oder seltener (5–10%) auch Hirnabszessen, die wichtigste Manifestation.
Rain‐induced turbulence and air‐sea gas transfer
Authors: Zappa Christopher J. , Ho David T. , McGillis Wade R. , Banner Michael L. , Dacey John W. H. , Bliven Larry F. , Ma Barry , Nystuen Jeff
Published: July 2009

Results from a rain and gas exchange experiment (Bio2 RainX III) at the Biosphere 2 Center demonstrate that turbulence controls the enhancement of the air‐sea gas transfer rate (or velocity) k during rainfall, even though profiles of the turbulent dissipation rate are strongly influenced by near‐surface stratification. The gas transfer rate scales with for a range of rain rates with broad drop size distributions. The hydrodynamic measurements elucidate the mechanisms responsible for the rain‐enhanced k results using SF6 tracer evasion and active controlled flux technique. High‐resolution k and turbulence results highlight the causal relationship between rainfall, turbulence, stratification, and air‐sea gas exchange. Profiles of ɛ beneath the air‐sea interface during rainfall, measured for the first time during a gas exchange experiment, yielded discrete values as high as 10−2 W kg−1. Stratification modifies and traps the turbulence near the surface, affecting the enhancement of the transfer velocity and also diminishing the vertical mixing of mass transported to the air‐water interface. Although the kinetic energy flux is an integral measure of the turbulent input to the system during rain events, ɛ is the most robust response to all the modifications and transformations to the turbulent state that follows. The Craig‐Banner turbulence model, modified for rain instead of breaking wave turbulence, successfully predicts the near‐surface dissipation profile at the onset of the rain event before stratification plays a dominant role. This result is important for predictive modeling of k as it allows inferring the surface value of ɛ fundamental to gas transfer.
Recent changes in the Greenland–Scotland overflow‐derived water transport inferred from hydrographic observations in the southern Irminger Sea
Authors: Sarafanov Artem , Falina Anastasia , Mercier Herlé , Lherminier Pascale , Sokov Alexey
Published: July 2009

Recent decadal changes (1955–2007) in the baroclinic transport (TBC) of the Deep Western Boundary Current (DWBC) carrying the Greenland–Scotland overflow‐derived waters along the East Greenland slope are quantified from a set of hydrographic sections in vicinity of Cape Farewell. The updated historical record of TBC shows clear decadal variability (±2–2.5 Sv) with the transport minima in the 1950s and mid‐1990s, maximum in the early 1980s and moderate‐to‐high transport in the 2000s. Since the mid‐1990s, the DWBC TBC has increased by ∼2 Sv (significant at the 99.9% level), which constitute ∼20% of the mean absolute transport (9.0 Sv) as obtained from three cruises in 2002–2006. The DWBC TBC anomalies negatively correlate (R = –0.80) with thickness anomalies of the Labrador Sea Water (LSW) at its origin implying a close association, albeit not necessarily causative, between the DWBC transport east of Greenland and the LSW production.
Energy relaxation in collisions of hydrogen and deuterium with oxygen atoms
Authors: Zhang P. , Kharchenko V. , Jamieson M. J. , Dalgarno A.
Published: July 2009

Collision energy transfer processes between hydrogen, deuterium, and oxygen atoms in the upper atmospheres of the terrestrial planets are studied. A new set of interaction potentials has been constructed using an accurate ab initio method. Full orientation‐dependent scattering cross sections have been obtained quantum mechanically and have been incorporated into the construction of the linear Boltzmann kinetic equation describing the energy relaxation process. The isotope and temperature dependence of the energy relaxation parameters have been analyzed. Distributions of the secondary energetic recoil atoms have been computed and the fractions of hot atoms capable of escaping from the atmospheres of the terrestrial planets have been determined. For applications to atmospheric physics and astrophysics, we have computed effective hard sphere cross sections for O + H and O + D collisions that closely reproduce the energy relaxation kinetics obtained from the linear Boltzmann equation. These effective cross sections, which are functions of the laboratory frame collisional energy and the temperature of the bath gas, may be used in simulations of the thermalization of hot O, H, and D atoms and their escape from planets.