bluuebunny/crossref_metadata_2025 huggingface dataset:
Klare Sicht im Blut durch Beleuchtung mit Infrarot‐Lasern
Authors: Rattunde Marcel , Krisch Ingo
Published: February 2011

Ein wichtiges Instrument in der modernen Medizin sind minimal‐invasive, endoskopische Verfahren, auch unter dem Schlagwort Schlüsselloch‐Medizin bekannt. Bei diesen sind im Gegensatz zu herkömmlichen chirurgischen Eingriffen keine großen Schnitte nötig sind, da miniaturisierte medizinische Instrumente Verwendung finden, die bereits durch sehr kleine Öffnungen in den Körper eingeführt werden können. Da der Operateur in diesem Fall keine direkte Sicht auf den zu operierenden Bereich hat, wird gleichzeitig ein Video‐Endoskop eingeführt, dessen Live‐Bilder auf einem Bildschirm beobachtet werden können und anhand derer die Operation oder Untersuchung gesteuert wird. Diese minimalinvasiven Verfahren sind heutzutage Standard bei einer Vielzahl von Eingriffen (z. B. in der Bauchhöhle), können jedoch in blutgefüllter Umgebung (z. B. im Herz oder Blutgefäßen) nicht angewendet werden, da bisherige endoskopische Systeme kein klares Bild durch Blut hindurch liefern können.
Der Solarisation auf der Spur
Authors: Zoheidi Mohammad , Heinze Alexander , Rosenow Ralitsa , Huth Andreas
Published: February 2011

Infolge der zunehmenden Anforderungen in der UV‐Technik werden Übertragungssysteme benötigt, welche die hohe Energie der UV‐Photonen nahezu verlustfrei transportieren sollen. Im UV‐Wellenlängenbereich, speziell 190 nm <λ < 240 nm, zeigen die herkömmlichen Quarzglasfasern der optischen Übertragungssysteme eine Degradation der Transmission, welche als Solarisation bezeichnet wird und u.U. bis zur völligen „Erblindung”︁ des Systems führen.
Noise in Laser Technology
Authors: Paschotta Rüdiger
Published: February 2011

Here, we discuss noise of pulsed lasers, which is in various respects different from that of continuous‐wave lasers. The first part of this series treated noise of the intensity and phase of continuous‐wave lasers. Pulsed lasers (e. g. Q‐switched lasers) are different in some respects, both concerning the mathematical description and physical features. In some important application areas such as laser material processing, noise properties may be of limited interest, although even in that area there can be impacts e. g. of pulse energy fluctuations on the processing quality. Other pulsed laser systems are used for example for LIDAR, where noise properties can be quite essential. Beam pointing fluctuations, as can occur in both continuous‐wave and pulsed lasers, will be discussed in the next part of this series. Mode‐locked lasers are not considered in this article; they do emit pulses, but on a much shorter time scale, and the involved physics are partly quite different.
Der Europäische Bildverarbeitungsmarkt im Überblick
Authors: Breyer Andreas
Published: February 2011

Die industrielle Bildverarbeitung in Europa ist in den vergangenen Jahren stetig gewachsen. Die jährliche EMVA‐Studie „European Vision Technology Market Statistics”︁ zeigt, dass trotz erster Zeichen des globalen konjunkturellen Abschwungs 2008 ein weiteres Rekordjahr für die Branche war. Insbesondere Vision Sensoren und Software waren gefragt.
Optical Coherence Tomography
Authors: Kaschke Michael , Meyer Scott , Everett Matthew , Grahl Marc
Published: February 2011

OCT technology has revolutionized ophthalmology. Cross‐sectional scans of the eye and quantitative analysis are now critical for the diagnosis and monitoring of many ocular diseases. The adoption of OCT took time, however. In retrospect, ophthalmic OCT evolved through a series of “5‐year” steps from invention to adoption and proliferation. Success came through close collaboration between researchers in academia, clinical users, and industry. The full potential of OCT in medical applications has yet to be achieved: there are opportunities for both further advances in ophthalmic imaging and adoption in new fields of medicine.
Flow Cytometry: OPSL Technology Meets Critical Needs
Authors: Schulze Matthias , Lepert Arnaud
Published: February 2011

Flow cytometry is a widely used tool for counting and/or sorting cells in both clinical and research medical applications, as well as animal husbandry and testing of genetically modified organisms. One important cytometry trend is the use of more laser wavelengths in order to simultaneously and optimally excite a higher number of fluorescent labels. This, in turn, allows counting or sorting on the basis of a larger number of parameters in a single instrument, which reduces overall measurement time and cost.
Micro‐Optics: From High‐End to Mass‐Market
Authors: Voelkel Reinhard
Published: February 2011

Photonics is said to be the most important key technology in the 21st century, some even call the 21st century the “photon century”. It might be a bit too early to name a whole century after it, but indeed, photon‐based technology has much impact on our everyday life at the beginning of the new century. Chip manufacturing, lighting, health care and life‐sciences, space, defense, and the transport and automotive sector rely on photon‐based technology. Photonics is also supposed to offer novel solutions where today's conventional technologies reach their limits in terms of velocity, capacity and accuracy.
„Aspheric Freedoms”︁ of Glass
Authors: Kunz Andreas F.
Published: February 2011

Traditionally, the cost‐conscious optical designer tended to avoid using aspheres, but today he finds himself deliberately incorporating them in products manufactured in medium to large numbers. This is thanks to the advent of precision glass moulding, which has allowed the cost‐effective manufacture of aspheric glass lenses.
Leuchtende Zukunft für effiziente weiße OLEDs
Authors: Leo Karl , Lüssem Björn , Polte Anette , Reineke Sebastian
Published: February 2011

Tagsüber transparente und nachts leuchtende Fensterscheiben, leuchtende Tapeten oder Fliesen, durchsichtige Displays? Organische Leuchtdioden eröffnen viele faszinierende und neue Anwendungsfelder. Erste Produkte wie Fernseher, mp3‐Player oder Handy nutzen bereits ein Display aus organischenLeuchtdioden und profitieren von der hohen Energieeffizienz und dem überragenden Kontrast der OLEDs. Allerdings spielen die organischen Leuchtdioden ihre ganze Stärke hinsichtlich ihres geringen Energiebedarfs bei einem anderen Anwendungsfeld aus: der Beleuchtungstechnik.
STED‐Mikroskopie
Authors: Sieber Jochen J. , Schué Anja
Published: February 2011

Die ultra‐hochauflösende Lichtmikroskopie hat den Lebenswissenschaften zu einem beachtlichen Sprung in ihrer Entwicklung verholfen. Noch vor wenigen Jahren war es für Biologen und Mediziner undenkbar, Strukturen kleiner als 100 nm aufzulösen oder gar dynamische Prozesse in lebenden Zellen zu beobachten. Die STED‐Mikroskopie (STimulated Emission Depletion) ermöglicht der biomedizinischen Forschung heute neue Einblicke in die Welt jenseits der Beugungsgrenze. Auch wenn die Ultra‐Hochauflösung auf komplexer optischer Technologie beruht, sind kommerziell erhältliche STED‐Systeme ebenso leicht zu bedienen wie konventionelle, weit verbreitete Konfokalmikroskope. Dieser Artikel erläutert die Entwicklung der STED‐Mikroskopie von der Idee bis zur neuesten Gerätegeneration für Lebendzelluntersuchungen.
Strukturierte Beleuchtung in der Hochauflösungsmikroskopie
Authors: Weisshart Klaus , Novikau Yauheni , Krampert Gerhard , Kempe Michael
Published: February 2011

Wer als Zellbiologe hätte sich nicht schon immer gewünscht, mit seinem Lichtmikroskop feinste Details in der Zelle aufzulösen? Denn die Struktur einer biologischen Einheit sagt viel über ihre Funktionsweise und Dynamik aus. Den Strich durch die Rechnung macht nicht die biologische Probe selbst, sondern ein physikalisches Gesetz, welches Ernst Abbe bereits 1873 formulierte [1]. Es besagt, dass die Auflösung eines Weitfeld Lichtmikroskops durch die Beugung fundamental begrenzt ist. Es gibt aber mittlerweile erfolgreiche Ansätze, das Mikroskop und die mikroskopische Abbildung so zu modifizieren, dass eine Auflösung jenseits des Abbeschen Gesetzes möglich wird. Eines dieser Verfahren ist die strukturierte Beleuchtungsmikroskopie (SIM; engl. „Structured Illumination Microscopy”︁).
Wellenleitermodulatoren für neue Einsatzgebiete
Authors: Ruske Jens‐Peter
Published: February 2011

Integriert‐optische Modulatoren werden vielfach in der optischen Telekommunikation eingesetzt. Durch Modifikation der Herstellungs‐ und Aufbautechnik kann nun auch eine schnelle Modulation von Licht hoher Leistung im Nahinfraroten, die Verarbeitung ultrakurzer Pulse und die Modulation von sichtbarem Licht erfolgen. Das eröffnet neue Anwendungen in den Bereichen Lasermaterialbearbeitung, Photo‐ und Displaytechnik sowie in der Messtechnik.
EMVA 1288 Standard for Machine Vision
Authors: Jähne Bernd
Published: February 2011

Choosing the suitable camera for a given machine vision application often proves to be a challenging task. The data sheets provided by the manufacturers are difficult to compare. Frequently, vital pieces of information are not available and the user is forced to conduct a costly comparative test which still may fail to deliver all relevant camera parameters. This is where the EMVA 1288 Standard comes in. It creates transparency by defining reliable and exact measurement procedures as well as data presentation guidelines. Version 3 of the standard has been released officially in March 2010. The standard has meanwhile gained international attention and its procedures have been verified by an international field test including labs from all over the world.
Noise in Laser Technology
Authors: Paschotta Rüdiger
Published: February 2011

This part discusses fluctuations of the beam pointing direction, or more generally of the position of the laser modes.
Out of the Economic Slowdown
Authors: Diepenbrock Stefan , Ladwig Birgit
Published: February 2011

Without doubt, photonics is one of the key industries of the future for the German economy. This is despite the fact that the importance of photonics is not widely acknowledged by the general public. Irrespective of this, photonics products can be found in nearly all spheres of life and the photonics industry remains highly innovative, experiences above average growth rates and employs more than 110,000 people. The photonics industry lacks public recognition because its technologies are spread across a wide spectrum of discrete industries. Whether it is a tiny component or more complex machinery, photonic technologies are traditionally apportioned to the corresponding areas of application. Without photonics, however, there would be no semiconductor production, no solar energy harvesting, no digital cameras and no flat screen TVs.
Research & Technology: Optic & Photonic 2/2010
Authors: Scharf Rainer
Published: February 2011

Dielectric Gratings Come into Focus

Steering the Beam of a Microlaser

Miniaturized 3D Worlds

Video‐rate STeD
Photonic Crystal Fiber
Authors: Hansen Kim , Imam Husain
Published: February 2011

Reducing the complexity of opticalsystems emphasizes the need to increase the number of optical functions in as few modules as possible, making the system more compact and simple to operate. Optical functions such as light generation, frequency conversion, amplification, broadband transmission, wavelength filtering and interfacing to the outside environment typically needed separate, individual optical components to be chained together to comprise a system. However, with the advent of Photonic Crystal Fiber, many of these functions can be combined into multifunctional modules paving the way for simpler, turn‐key systems.
Creating Complex Coatings
Authors: MacMillan Iain , Weinacht Martin
Published: February 2011

The fabrication of high precision optical coatings has historically used evaporative deposition because of high costs and low production volumes associated with sputtering techniques. However, improvements in substrate handling and sputtering production have made sputtering more efficient.

Improved handling techniques, such as load‐locked vacuum chambers, have greatly reduced coating chamber downtime. Likewise dual magnetron and advanced plasma reactive sputtering coating platforms have markedly increased filter throughput allowing the fabrication of highly complex coatings with several hundred layers designed to meet the requirements of today's cutting edge applications such as biotech and analytical instrumentation, fluorescence microscopy and advanced spectroscopy.
Laser‐Based Particle Acceleration
Authors: Kaluza Malte Christoph
Published: February 2011

Using state‐of‐the‐art high‐power laser systems, we are able to routinely generate extreme energy densities and focused light intensities in a controlled laboratory environment. During the interaction of these laser pulses with matter a plasma is generated that can both sustain and support huge electric fields. These can be used as a novel type of accelerator structure for electrons and ions having properties favorable for a large number of future applications.
Blickrichtungsbestimmung in Echtzeit
Authors: Husar Peter , Klefenz Frank
Published: February 2011

Das Bestimmen der Blickrichtung eines Auges ist für die Bildverarbeitung eine große Herausforderung. Gängige ‚Eye Tracker’︁ benötigen in der Regel eine aufwändige Kalibrationsprozedur. Ein echtzeitfähiges, kalibrationsfreies System mit Bildraten von über 1000 fps wurde nun von Forschern des FraunhoferInstituts für Digitale Medientechnologie (IDMT) entwickelt.
Bildverarbeitung in der Medizin
Authors: Roman Jean‐Philippe
Published: February 2011

„Medical Imaging”︁ ist in der Medizin kein neues Thema. Man versteht darunter meist komplexe Technologien, die einen nicht‐invasiven Einblick in den Körper ermöglichen. Was mit den Röntgenstrahlen begann, ist inzwischen mit CT, MRT, Ultraschall usw. zur Radiologie, einer vollwertigen ärztlichen Fachdisziplin, geworden. Die Fähigkeit, den Körper ganz oder teilweise durchleuchten zu können, ist mit vielen Fortschritten der modernen Medizin verbunden und eine wertvolle Ergänzung der äußerlichen Untersuchung durch den Arzt geworden. Zusätzlich zu den klassischen Radiologie‐Technologien hält auch die Bildverarbeitung mit Digitalkameras Einzug in immer mehr medizinische Applikationen.
Beleuchtung ist das A und O!
Authors: Perrot Sophie
Published: February 2011

Die Bedeutung der geeigneten Beleuchtung für ein Bildverarbeitungs‐System wird häufig unterschätzt. Dabei ist die Auswahl der richtigen Lichtquelle ausschlaggebend für die Qualität der Bildaufnahme und kann die anschließende Bildauswertung stark vereinfachen. Dieses Tutorial gibt einige Hilfestellungen, die passende Beleuchtung zur jeweiligen Aufgabe zu finden.
Highest intensities, shortest pulses
Authors: Tajima Toshiki , Habs Dietrich , Mourou Gérard A.
Published: February 2011

The Extreme Light Infrastructure (ELI) [1] will be the first research infrastructure dedicated to the fundamental study of laser‐matter interaction in the ultra‐relativistic regime. It provides the link between high‐field science and ultrafast science. It further offers a few gigantic steps towards connecting optics, high‐energy physics, nuclear physics, medicine and nuclear engineering, only to name a few.
Light for treating skin diseases
Authors: Seme Bernd , Marke Swen , Meyer Andreas , Streit Ingolf
Published: February 2011

Narrowband UVB radiation centered at about 308 nm is widely used in dermatology for the treatment of common skin disorders like psoriasis. Light sources used for this kind of phototherapy are excimer lasers and dielectric barrier discharge (DBD) lamps. Electrodeless exciplex lamps are a new approach to obtain a simple, long‐living and environment‐friendly UVB device that every dermatologist can afford. A first demonstration device has been built within a joint research project. In a clinical test with 20 patients it could be demonstrated that the new lamp is well‐suited for hospital use and capable of easing psoriasis significantly.
More Moore & more quality
Authors: Bonerz Jens
Published: February 2011

The complexity of integrated circuits doubles at a remarkable speed — each 18 to 24 months, according to industry insiders. In 1965, Gordon Moore discovered this effect for the first time. Until today, pursuing Moore's Law poses a significant challenge for many industrial sectors because higher complexity in products means more complexity with regard to quality assurance during production as well. Optical surface inspection and metrology solutions have proven to be the right choice when it comes to enabling product innovations within short development cycles.
New and/or improved aspects of fetal surgery
Authors: Luks François I.
Published: February 2011

Open fetal surgery through a wide hysterotomy is no longer a real option for prenatal intervention, but a minimally invasive approach has emerged as treatment for a small number of indications. Endoscopic ablation of placental vessels is the preferred treatment for severe twin‐to‐twin transfusion syndrome and it may be the only chance to salvage the most severe forms of congenital diaphragmatic hernia. Several other indications are currently under review and may become justified in the future, provided that diagnostic accuracy and patient selection become more accurate. Before invasive fetal intervention becomes widely accepted, however, we need to better define outcome. It is no longer acceptable to express results in terms of survival at birth. Survival at discharge and long‐term morbidity must be considered as well. Copyright © 2011 John Wiley & Sons, Ltd.
Parents' perspectives on the unforeseen finding of a fetal sex chromosomal aneuploidy
Authors: Pieters J. J. P. M. , Kooper A. J. A. , Eggink A. J. , Verhaak C. M. , Otten B. J. , Braat D. D. M. , Smits A. P. T. , van Leeuwen E.
Published: February 2011

Objective

To investigate the parental perspectives of being confronted with an unforeseen fetal sex chromosomal aneuploidy (SCA), in light of the fact that this accidental finding is avoidable by rapid aneuploidy detection (RAD).

Methods

Exploratory qualitative interview study. We conducted 16 semi‐structured interviews with parents who decided to continue pregnancy after the unforeseen finding of a fetal SCA.

Results

The communication of the unforeseen finding of SCA; the informed decision‐making process concerning the pregnancy follow‐up and the child and its future were the extracted themes. Parents were not prepared to accidental findings in routine prenatal diagnostics. All started an unguided search on the Internet. It is not at all clear whether parents have preference for an RAD test with X and Y probes Parents were satisfied with the post‐test professional information they received to make an informed decision, whereas after birth questions still remained to be answered.

Conclusion

Parents' perspectives may serve as major contributors to research on the question whether or not the X and Y probes should be standard included for purposes of RAD. The fact that RAD has the possibility to avoid accidental findings of SCAs, brings up the question whether any benefits outweigh the potential harms. Copyright © 2011 John Wiley & Sons, Ltd.
Introduction of a counselling service for patients with type 1 diabetes: better glycaemic control and reduced anxiety
Authors: Masding MG , Ashley K , Klejdys S
Published: February 2011

Self‐management of type 1 diabetes (T1DM) can be undermined by anxiety about life events; consequently, we introduced a counselling service for people with T1DM (using Person Centred Integrative Counselling) to address their concerns and anxieties about their condition, and this involved a six‐week course of 50‐minute sessions with a qualified and experienced counsellor. We have evaluated the counselling service, looking for benefits for the participants.

We undertook a retrospective analysis of data obtained for people referred to the service between June 2007 and June 2010, pre‐ and post‐attendance at the course of counselling. Outcomes were HbA1c as a measure of glycaemic control, and scores from the Clinical Outcomes in Routine Evaluation (CORE) questionnaire (a measure of feelings of anxiety and risk) to assess the effectiveness of the counselling.

Of 79 people referred, 62 completed the course. There was no difference between those who did or did not complete in terms of demographic data, pre‐counselling HbA1c or pre‐counselling CORE score. Of those who completed the course, there were reductions in HbA1c (pre‐counselling [median (range)] 9.5% [6.2, 17.8], post‐counselling 9.3% [5.9, 11.4]; p=0.007) and CORE score (pre‐counselling [mean ± SD] 1.60±0.71, post‐counselling 0.89±0.57; p<0.001).

Completion of a course of counselling sessions was associated with improvements in glycaemic control and reduction in anxiety and risk about T1DM. This may be an effective intervention in helping patients with T1DM to self‐manage their condition. Copyright © 2011 John Wiley & Sons.
Type II polyglandular autoimmune syndrome: an unusual presentation
Authors: Phillips SM , Butt MI , Robinson AM
Published: February 2011

A previously fit and well 35‐year‐old man presented to the acute medical take with a three‐week history of general malaise; he complained of polyuria, polydipsia, weight loss, abdominal pain and vomiting. He was diagnosed with type 1 diabetes (capillary blood glucose 20.7mmol/L) but was not ketoacidotic (pH 7.43) and was commenced on intravenous fluids and an intravenous insulin infusion. After four hours of appropriate fluid resuscitation and normalisation of blood glucose, the patient had deteriorated becoming tachycardic and hypotensive. At this time the patient was reassessed and a short synacthen test with a baseline ACTH was carried out. Hydrocortisone was administered to the patient immediately after the short synacthen test. Addison's disease was confirmed (cortisol 0 minutes: 315nmol/L, 30 minutes: 337nmol/L, ACTH 627ng/L).

Further investigations during that admission also identified primary hypothyroidism (TSH 48.5mU/L, free T4 19.2pmol/L) but no other endocrinopathies. For the first time in the literature this is a case report of a young man presenting with type 1 diabetes, Addison's disease and primary hypothyroidism simultaneously. Copyright © 2011 John Wiley & Sons.
Information giving and receiving in hematological malignancy consultations
Authors: Alexander Stewart C. , Sullivan Amy M. , Back Anthony L. , Tulsky James A. , Goldman Roberta E. , Block Susan D. , Stewart Susan K. , Wilson‐Genderson Maureen , Lee Stephanie J.
Published: February 2011

Purpose: Little is known about communication with patients suffering from hematologic malignancies, many of whom are seen by subspecialists in consultation at tertiary‐care centers. These subspecialized consultations might provide the best examples of optimal physician–patient communication behaviors, given that these consultations tend to be lengthy, to occur between individuals who have not met before and may have no intention of an ongoing relationship, and which have a goal of providing treatment recommendations. The aim of this paper is to describe and quantify the content of the subspecialty consultation in regards to exchanging information and identify patient and provider characteristics associated with discussion elements.

Methods: Audio‐recorded consultations between 236 patients and 40 hematologists were coded for recommended communication practices. Multilevel models for dichotomous outcomes were created to test associations between patient, physician and consultation characteristics and key discussion elements.

Results: Discussions about the purpose of the visit and patient's knowledge about their disease were common. Other elements such as patient's preference for his/her role in decision‐making, preferences for information, or understanding of presented information were less common. Treatment recommendations were provided in 97% of the consultations and unambiguous presentations of prognosis occurred in 81% of the consultations. Unambiguous presentations of prognosis were associated with non‐White patient race, lower educational status, greater number of questions asked, and specific physician provider.

Conclusion: Although some communication behaviors occur in most consultations, others are much less common and could help tailor the amount and type of information discussed. Approximately half of the patients are told unambiguous prognostic estimates for mortality or cure. Copyright © 2011 John Wiley & Sons, Ltd.
Desirability function combining metabolic stability and functionality of peptides
Authors: Van Dorpe Sylvia , Adriaens Antita , Vermeire Simon , Polis Ingeborgh , Peremans Kathelijne , Spiegeleer Bart De
Published: February 2011

The evaluation of peptides as potential therapeutic or diagnostic agents requires the consideration of several criteria that are targeted around two axes: functionality and metabolic stability. Most often, a compromise has to be made between these mutually opposing characteristics.

In this study, Derringer's desirability function, a multi‐criteria decision‐making method, was applied to determine the best peptide for opioid studies in a single figure‐of‐merit.

The penetration of the blood–brain barrier (BBB) determines the biological functionality of neuropeptides in the brain target tissue, and consists of an influx and an efflux component. The metabolic stability in the two concerned tissues, i.e. plasma and brain, are taken into consideration as well. The overall selection of the peptide drug candidate having the highest BBB‐drugability is difficult due to these conflicting responses as well as the different scalings of the four biological parameters under consideration.

The highest desirability, representing the best BBB‐drugability, was observed for dermorphin. This peptide is thus the most promising drug candidate from the set of eight opioid peptides that were investigated. The least desirable candidate, with the worst BBB influx and/or metabolic stability, was found to be CTAP. Validation of the desirability function by in vivo medical imaging showed that dermorphin and DAMGO penetrate the BBB, whereas EM‐1 and TAPP did not. These results are thus consistent with those obtained with the desirability evaluation.

To conclude, the multi‐criteria decision method was proven to be useful in biomedical research, where a selection of the best candidate based on opposing characteristics is often required. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
Light emission and floating gate memory characteristics of germanium nanocrystals
Authors: Das Samaresh , Manna Santanu , Singha Rajkumar , Anopchenko Aleksei , Daldosso Nicola , Pavesi Lorenzo , Dhar Achintya , Ray Samit Kumar
Published: February 2011

We report Ge nanocrystals (NCs) based dual functional light emitting and metal insulator semiconductor (MIS) flash memory devices, fabricated by rf sputtering. Transmission electron micrographs revealed the formation of spherically shaped Ge NCs. We have observed broad electroluminescence (EL) around 760 nm, which is attributed to electron–hole recombination in quantum confined Ge NCs. The dependence of integrated EL intensity on drive currents has also been studied. An anti‐clockwise hysteresis behaviour is observed in capacitance–voltage measurements of MIS devices for different sweep voltages, indicating net electron trapping in NC based floating gates.
Radar climatology of the COPS region
Authors: Weckwerth Tammy M. , Wilson James W. , Hagen Martin , Emerson Tracy J. , Pinto James O. , Rife Daran L. , Grebe Leslie
Published: February 2011

A climatology of convection initiation (CI) and convective enhancements (CE) has been developed using radar reflectivity data in southwestern Germany and eastern France over the period of May–August of 2000–2006 and 2008. The study region included the Vosges Mountains of France, the Rhine Valley which straddles France and Germany, the Black Forest Mountains and the Swabian Mountains of Germany. Convection occurred frequently during the summer months throughout the study region. The CI density (number of initiations per square km) illustrates preferential formation in the mountain regions while the CE events spanned both mountains and valleys nearly equally. There is a strong mid‐day peak of the CI events suggesting that diurnal heating is critical for CI in the region. The very strong thunderstorms (>46 dBZ) first occurred in the mountains and ∼2 h later in the Rhine Valley.

During the summer of 2007, the Convective and Orographically‐induced Precipitation Study (COPS) field campaign was conducted with the objective of obtaining improved understanding of convective processes and short‐term quantitative precipitation forecasting in low‐mountain regions. Comparisons were made between the radar climatology results and the COPS summer. The COPS summer exhibited preferential CI density in the mountainous regions but not as pronounced as the climatology. The COPS summer had a similar diurnal peak of CI events as climatology but the ratio of daytime to nighttime CI (1.7), or amplitude of the diurnal cycle, was less than that of climatology (3.0). While both the 8‐year climatology and COPS summer were dominated by daytime, locally‐forced CI occurrences, the broad distribution of daytime CI events and increase in nighttime events observed during COPS indicate a more active synoptic pattern in 2007. Copyright © 2011 Royal Meteorological Society
Application of the stochastic resonance algorithm to the simultaneous quantitative determination of multiple weak peaks of ultra‐performance liquid chromatography coupled to time‐of‐flight mass spectrometry
Authors: Deng Haishan , Shang Erxin , Xiang Bingren , Xie Shaofei , Tang Yuping , Duan Jin‐ao , Zhan Ying , Chi Yumei , Tan Defei
Published: February 2011

The stochastic resonance algorithm (SRA) has been developed as a potential tool for amplifying and determining weak chromatographic peaks in recent years. However, the conventional SRA cannot be applied directly to ultra‐performance liquid chromatography/time‐of‐flight mass spectrometry (UPLC/TOFMS). The obstacle lies in the fact that the narrow peaks generated by UPLC contain high‐frequency components which fall beyond the restrictions of the theory of stochastic resonance. Although there already exists an algorithm that allows a high‐frequency weak signal to be detected, the sampling frequency of TOFMS is not fast enough to meet the requirement of the algorithm. Another problem is the depression of the weak peak of the compound with low concentration or weak detection response, which prevents the simultaneous determination of multi‐component UPLC/TOFMS peaks. In order to lower the frequencies of the peaks, an interpolation and re‐scaling frequency stochastic resonance (IRSR) is proposed, which re‐scales the peak frequencies via linear interpolating sample points numerically. The re‐scaled UPLC/TOFMS peaks could then be amplified significantly. By introducing an external energy field upon the UPLC/TOFMS signals, the method of energy gain was developed to simultaneously amplify and determine weak peaks from multi‐components. Subsequently, a multi‐component stochastic resonance algorithm was constructed for the simultaneous quantitative determination of multiple weak UPLC/TOFMS peaks based on the two methods. The optimization of parameters was discussed in detail with simulated data sets, and the applicability of the algorithm was evaluated by quantitative analysis of three alkaloids in human plasma using UPLC/TOFMS. The new algorithm behaved well in the improvement of signal‐to‐noise (S/N) compared to several normally used peak enhancement methods, including the Savitzky‐Golay filter, Whittaker‐Eilers smoother and matched filtration. Copyright © 2011 John Wiley & Sons, Ltd.
Chemical ionization by [NO]+ and subsequent collision‐induced dissociation for the selective on‐line detection of monoterpenes and linalool
Authors: Rimetz‐Planchon Juliette , Dhooghe Frederik , Schoon Niels , Vanhaecke Frank , Amelynck Crist
Published: February 2011

Existing on‐line Chemical Ionization Mass Spectrometry (CIMS) techniques for quantification of atmospheric trace gases, such as Biogenic Volatile Organic Compounds (BVOCs), suffer from difficulty in discriminating between isomeric (and more generally isobaric) compounds. Selective detection of these compounds, however, is important because they can affect atmospheric chemistry in different ways, depending on their chemical structure. In this work, Flowing Afterglow Tandem Mass Spectrometry (FATMS) was used to investigate the feasibility of the selective detection of a series of monoterpenes, an oxygenated monoterpene (linalool) and a sesquiterpene (β‐caryophyllene). Ions at m/z 137 from [H3O]+ chemical ionization of α‐pinene, linalool and β‐caryophyllene have been subjected to Collision‐Induced Dissociation (CID) with Ar in the collision cell of a tandem mass spectrometer at center‐of‐mass energies ranging between 0 and 8 eV. Similar fragmentation patterns were obtained, demonstrating that this method is not suited for the selective detection of these compounds. However, CID of the ions at m/z 136 produced via [NO]+ chemical ionization of a series of monoterpenes has revealed promising results. Some tracer‐product ions for individual compounds or groups of compounds were found, which can be considered as a step forward towards selective on‐line monitoring of BVOCs with CIMS techniques. Copyright © 2011 John Wiley & Sons, Ltd.
Efficient cell culture systems for hepatitis E virus strains in feces and circulating blood
Authors: Okamoto Hiroaki
Published: February 2011

Attempts have been made to propagate hepatitis E virus (HEV) in primary hepatocyte culture and various other cultured cells. However, the replication ability of HEV recovered from culture media remains extremely low. Recently, efficient culture systems have been established in PLC/PRF/5 (hepatocellular carcinoma) and A549 (lung cancer) cell lines for HEV strains of genotypes 3 and 4 in our laboratory. They originated in fecal extracts from patients containing HEV RNA in extremely high‐titers (107 copies/ml), and named the JE03‐1760F (genotype 3) and HE‐JF5/15F (genotype 4) strains, respectively. HEV RNA in culture supernatants reached 108 copies/ml in titer, and were transmitted successively through many passages. An infectious HEV cDNA clone (pJE03‐1760F/wt) was constructed that has replication activity comparable to that of the wild‐type JE03‐1760F in feces. The ORF3 protein is indispensable for shedding HEV particles from cells in the reverse genetics system. HEV recovered from culture media, as well as circulating HEV, possess ORF3 proteins on the surface and are covered with cellular membranes, and therefore, ORF2 epitopes are buried in these particles. In contrast, HEV excreted into feces are naked nucleocapsids without a lipid layer or surface expression of the ORF3 protein. HEV in sera of patients with acute hepatitis E can infect and replicate in PLC/PRF/5 and A549 cells, with efficiency comparable to the circulating HEV RNA levels. High‐efficiency cell culture systems for infectious viruses, thus developed, are expected to open up a new era and resolve many mysteries in the epidemiology, molecular biology, and treatment of HEV. Copyright © 2011 John Wiley & Sons, Ltd.
THE RELATIONSHIP BETWEEN FINE SEDIMENT AND MACROPHYTES IN RIVERS
Authors: Jones J.I. , Collins A.L. , Naden P.S. , Sear D.A.
Published: February 2011

The interplay between erosion and deposition are fundamental characteristics of river basins. These processes result in the delivery, retention and conveyance of sediment through river systems. Although the delivery of sediment to rivers is a natural phenomenon, in recent years there has been increasing concern about the enhancement of sediment loadings as a result of anthropogenic activities. The presence of macrophytes in river channels tends to increase the retention of fine sediment leading to changes in bed composition. However, a complex relationship exists between macrophytes and fine sediment: macrophytes affect the conveyance of fine sediment and are, in turn, affected by the sediment loading. This review deals with these two reciprocal effects and, in particular, summarizes the available evidence base on the impact of fine sediment on macrophytes. Increased inputs of fine sediment appear to have both direct and indirect impacts on the macrophyte community, altering light availability, and the structure and quality of the river bed. The nature of these impacts depends largely on the rate of deposition and the nature of the material deposited. Changes in macrophyte community composition may ensue where the depositing material is more nutrient rich than the natural river bed. Many of the changes in macrophyte flora that occur with increased fine sediment inputs are likely to closely parallel those that occur with increased dissolved nutrient availability. If attempts to manage nutrient inputs to rivers are to achieve their goals, it is critical that fine sediment‐associated nutrient dynamics and transfers are considered. Copyright © 2011 John Wiley & Sons, Ltd.
SEDIMENT TRANSPORT AND FLOW DYNAMICS AROUND A RESTORED POOL IN A FISH HABITAT REHABILITATION PROJECT: FIELD AND 3D NUMERICAL MODELLING EXPERIMENTS
Authors: Biron P. M. , Carver R. B. , Carré D. M.
Published: February 2011

Few studies have examined sediment transport patterns around in‐stream structures used to enhance fish habitat despite the importance of this variable in the successful design of stream restoration schemes. The objective of this study is to examine interactions between the (excavated) pool morphology, flow and sediment transport in a restored reach of the Nicolet River (Quebec, Canada). Bedload transport was investigated using passive integrated transponder (PIT) tagged particles that were followed from positions upstream of a pair of current deflectors which were designed to maintain the excavated pool downstream. Three‐dimensional numerical simulations of the flow field at various flow stages (with emerged or submerged deflectors) were used to relate near‐bed velocity and bed shear stress to transport patterns and to assess the impact of varying the pool location and geometry on the flow field and water surface profiles. Results show that from 2005 to 2008, of the 117 pit‐tagged particles that fell in the pool, only 27 are known to have exited. None of the 30 largest rocks entering the pool escaped. Bed shear stress values simulated at high and peak flow (slightly above bankfull level) are not sufficient to move the largest rocks in the pool exit zone. Simulations also reveal a complex water surface topography when flow is above the height of deflectors, with negative water surface slope in the pool zone. When modifying the pool geometry so that the deepest zones are close to the apex of the in‐stream structures instead of in the centre of the channel, both water surface slope and near‐bed velocity patterns are greatly modified. Understanding the interactions between excavated pools, bedload and 3D velocity patterns around in‐stream structures is essential for long‐term success of fish habitat restoration projects, and using 3D models to test various designs of artificial pools is a promising approach. Copyright © 2011 John Wiley & Sons, Ltd.
PBTE as a research vehicle: A way out of the forest
Authors: Bruce Matthew H. , Bernard Miller H.
Published: February 2011

The move into Performance‐Based Teacher Education has been precipitous. Rather than a one‐shot move into what passes for a full PBTE format, a gradual phasing‐in operation concurrent with suitable research seems desirable. Without the research information, PBTE may become another bandwagon passing across the educational scene without making any discernible change in teacher education.

Some consistent view of the overall educational enterprise and of the teaching act, relating these to PBTE, is an absolute necessity. The PBTE move provides a useful research vehicle regardless of any verdict reached on its efficacy as a teacher education format.

Current funding of educational research on a scale appropriate to the kinds of questions needing study appears limited. This suggests that a viable approach to researching both those vital questions connecting what teachers do and acceptable goals for pupils and PBTE as a vehicle must employ existing program components such as microteaching. This also suggests similar research designs be employed in many places if the summation of results is to provide useful information.
A formal separation method of protocols to eliminate parallel attacks in virtual organization
Authors: Zhao Hui , Li Mingchu , Fan Xinxin
Published: February 2011

The purpose of this paper is to introduce a technique to eliminate parallel attacks to protocol in virtual organization (VO) through enforcing dynamic authorization policies. Grid realizes coordinated resource sharing across multiple management domains. VO is defined as a key concept for operation and management of grid services. Due to the fact that VO focuses on dynamic, cross‐organizational sharing relationships, one of the central challenges in the construction of scalable VO is that protocol specified by VO may have process of parallel running. To solve this problem, we present a formal definition of non‐honest participants' malicious coordination operations which are necessary for parallel attack counterexample in VO. Based on that, we present the two‐level dynamic authorization policy deploying scheme in VO for eliminating parallel attacks. Copyright © 2011 John Wiley & Sons, Ltd.
Bayesian hierarchical modeling for a non‐randomized, longitudinal fall prevention trial with spatially correlated observations
Authors: Murphy T. E. , Allore H. G. , Leo‐Summers L. , Carlin B. P.
Published: February 2011

Because randomization of participants is often not feasible in community‐based health interventions, non‐randomized designs are commonly employed. Non‐randomized designs may have experimental units that are spatial in nature, such as zip codes that are characterized by aggregate statistics from sources like the U.S. census and the Centers for Medicare and Medicaid Services. A perennial concern with non‐randomized designs is that even after careful balancing of influential covariates, bias may arise from unmeasured factors. In addition to facilitating the analysis of interventional designs based on spatial units, Bayesian hierarchical modeling can quantify unmeasured variability with spatially correlated residual terms. Graphical analysis of these spatial residuals demonstrates whether variability from unmeasured covariates is likely to bias the estimates of interventional effect.

The Connecticut Collaboration for Fall Prevention is the first large‐scale longitudinal trial of a community‐wide healthcare intervention designed to prevent injurious falls in older adults. Over a two‐year evaluation phase, this trial demonstrated a rate of fall‐related utilization at hospitals and emergency departments by persons 70 years and older in the intervention area that was 11 per cent less than that of the usual care area, and a 9 per cent lower rate of utilization from serious injuries. We describe the Bayesian hierarchical analysis of this non‐randomized intervention with emphasis on its spatial and longitudinal characteristics. We also compare several models, using posterior predictive simulations and maps of spatial residuals. Copyright © 2011 John Wiley & Sons, Ltd.
Supramolecular Polymers: Rigid Dimers Formed through Strong Interdigitated H‐Bonds Yield Compact 1D Supramolecular Helical Polymers (Small 3/2011)
Authors: Ciesielski Artur , Stefankiewicz Artur R. , Hanke Felix , Persson Mats , Lehn Jean‐Marie , Samorì Paolo
Published: February 2011

Hierarchical self‐assembly of small abiotic molecular modules interacting through noncovalent forces is increasingly being used to generate functional structures and materials for electronic, catalytic, and biomedical applications. The greatest control over the geometry in H‐bond supramolecular architectures, especially in H‐bonded supramolecular polymers, can be achieved by using conformationally rigid molecular modules undergoing self‐assembly through strong H‐bonds. Their binding strength depends on the multiplicity of the H‐bonds, the nature of donor/acceptor pairs and their secondary attractive/repulsive interactions. Here a functionalized molecular module is described, which is capable of self‐associating through self‐complementary H‐bonding patterns comprising four strong and two medium‐strength H‐bonds to form dimers. The self‐association of these phenylpyrimidine‐based dimers through directional H‐bonding between two lateral pyridin‐2(1H)‐one units of neighboring molecules allows the formation of highly compact 1D supramolecular polymers by self‐assembly on graphite. A concentration‐dependent study by scanning tunneling microscopy at the solid–liquid interface, corroborated by dispersion‐corrected density functional studies, reveals the controlled generation of either linear supramolecular 2D arrays, or long helical supramolecular polymers with a high shape persistence.
Assigning change requests to software developers
Authors: Kagdi Huzefa , Gethers Malcom , Poshyvanyk Denys , Hammad Maen
Published: February 2011

The paper presents an approach to recommend a ranked list of expert developers to assist in the implementation of software change requests (e.g., bug reports and feature requests). An Information Retrieval (IR)‐based concept location technique is first used to locate source code entities, e.g., files and classes, relevant to a given textual description of a change request. The previous commits from version control repositories of these entities are then mined for expert developers. The role of the IR method in selectively reducing the mining space is different from previous approaches that textually index past change requests and/or commits. The approach is evaluated on change requests from three open‐source systems:ArgoUML,Eclipse, andKOffice, across a range of accuracy criteria. The results show that the overall accuracies of the correctly recommended developers are between 47 and 96% for bug reports, and between 43 and 60% for feature requests. Moreover, comparison results with two other recommendation alternatives show that the presented approach outperforms them with a substantial margin. Project leads or developers can use this approach in maintenance tasks immediately after the receipt of a change request in a free‐form text. Copyright © 2011 John Wiley & Sons, Ltd.
Beyond words: Visual metaphors that can demonstrate comprehension of KM as a paradoxical activity system
Authors: McKenzie Jane , van Winkelen Christine
Published: February 2011

Following criticism that, in business and management, metaphor is largely verbal and primarily used to convey similarity, this paper explores how visual metaphors can communicate the anomalous and the paradoxical aspects of KM more concisely than words, whilst simultaneously presenting more tacit associations to stimulate creative thinking. It considers a series of 30 assessed posters that aimed to re‐present six basic KM paradoxes through imagery that captures both the analogous and the anomalous. We found six categories of radial metaphors able to convey paradoxical complexity in a concise way. This has implications for organizations thinking about how to engage people with both the familiar and the strange. Copyright © 2011 John Wiley & Sons, Ltd.