bluuebunny/crossref_metadata_2025 huggingface dataset:
RP‐HPLC determination of phenylalkanoids and monoterpenoids in Rhodiola rosea and identification by LC‐ESI‐TOF
Authors: Avula Bharathi , Wang Yan‐Hong , Ali Zulfiqar , Smillie Troy J. , Filion Vicky , Cuerrier Alain , Arnason John T. , Khan Ikhlas A.
Published: April 2009

An HPLC method permitting the simultaneous determination of fourteen analytes (phenylalkanoids and monoterpenoids) from the roots of Rhodiola rosea was developed. A separation was achieved within 35 min using C18 column material and a water–acetonitrile mobile phase, both containing a 0.05% phosphoric acid gradient system and a temperature of 53°C. The method was validated for linearity, repeatability, limits of detection and limits of quantification. The limits of detection and limits of quantification of 14 phenylalkanoids and monoterpenoids were found to be 0.20–1.0 and 0.5–3.5 µg/mL, respectively. The wavelengths used for quantification of phenylalkanoids and monoterpenoids with a diode array detector were 205, 220 and 251 nm. The method was used to analyze the roots of two species of Rhodiola and commercial extracts of R. rosea and provides preliminary evidence of phytochemical differences between North American and Eurasian populations of R. rosea. LC–mass spectrometry coupled with electrospray ionization (ESI) interface method is described for the identification of phenylalkanoids and monoterpenoids in various Rhodiola samples. This method involved the use of the [M + H]+, [M + NH4]+ and [M + Na]+ ions in the positive ion mode with extractive ion monitoring (EIM). Copyright © 2009 John Wiley & Sons, Ltd.
Rumination, goal linking, daily hassles and life events in major depression
Authors: McIntosh Emily , Gillanders David , Rodgers Sheelagh
Published: April 2009

Background: Rumination in response to stressful events and depressed mood leads to harmful outcomes. In addition to intra‐psychic processes, depression is also associated with daily hassles and major life events. Self‐regulatory beliefs such as goal linking could mediate the link between life events, daily hassles, rumination and major depression. Method: The relationships between depressed mood, rumination, goal linking, life events and daily hassles were investigated in a between‐groups design. Standardized questionnaire measures of these constructs were used to compare depressed participants with a group of people experiencing psychological distress, but not major depression, and a never‐depressed group. Results: Participants with major depression experienced similar numbers of life events as the other groups, though the impact of these was greater for the depressed group than either the psychological distress group or the healthy controls. Depressed participants also experienced greater daily hassles than either of the other two groups. Depressed participants were also higher in goal linking and rumination. Regression analysis demonstrated that neither life events nor goal linking predict rumination or depressed mood. Rumination appears to moderate the relationship between daily hassles and depressed mood. Discussion: Theoretical and clinical implications are discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Basic Processes in Complex (Dusty) Plasmas: Charging, Interactions, and Ion Drag Force
Authors: Khrapak S. , Morfill G.
Published: April 2009

Recent developments in the theoretical investigations of complex (dusty) plasmas – low temperature plasmas containing charged microparticles – are reviewed. The focus is mostly on important basic problems of plasmaparticle interactions, including particle charging, electric potential distribution around the particle, interparticle interactions, and the ion drag force. In particular, the importance of plasma‐neutral collisions (especially ionneutral) is emphasized (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stereoselective Chemoenzymatic Synthesis of Enantiopure 1‐(Heteroaryl)ethanamines by Lipase‐Catalysed Kinetic Resolutions
Authors: Alatorre‐Santamaría Sergio , Gotor‐Fernández Vicente , Gotor Vicente
Published: April 2009

The efficient chemical synthesis and enzymatic kinetic resolution of a family of 1‐(heteroaryl)ethanamines have been performed with lipases responsible for the preparation of nitrogenated compounds in high optical purity. Thus, Candida antarctica lipase type B has been identified as an excellent biocatalyst for the stereoselective production of the corresponding enantiomerically enriched (R)‐acetamides and (S)‐amines. A similar effect of the heteroatom in the cyclic ring has been observed in terms of reactivity and enantioselectivity, with benzoxazole, benzothiazole and benzimidazole derivatives being obtained with excellent enantiopurities after one day of reaction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
An implicit method for the Navier–Stokes equations on overlapping block‐structured grids
Authors: Ahusborde E. , Glockner S.
Published: April 2009

This paper deals with a method first introduced by Romé et al. in two articles. The authors reported that their method was suitable to run the Navier–Stokes equations efficiently on non‐matching and overlapping block‐structured meshes. However, there was a problem of mass conservation and a discontinuity of pressure through the interfaces in some cases. In the present paper, an improvement of the method based on a pressure correction scheme is proposed. With this improvement, the pressure is continuous through the interfaces and the incompressibility constraint is ensured over the whole domain. Several numerical tests were carried out to assess the proposed method. Copyright © 2009 John Wiley & Sons, Ltd.
Real‐time measurement of H/D exchange in a microdialysis Raman quartz cell
Authors: Carmona Pedro , Molina Marina
Published: April 2009

We present here a novel quartz cell for monitoring H/D exchange in biomolecules using Raman spectroscopy. This cell is combined with a syringe to pump heavy water through a hollow microdialysis fibre, which is inserted into the cell. The deuterium efflux into the sample has been studied as a function of the molecular weight cut‐off of the microdialysis fibre and compared with other microcell systems comprising conventional glass capillaries. The fastest D2O efflux that we have obtained (kd = 0.38 ± 0.008 min−1) permits to measure exchange rates of 2.5 min−1 or less. Application of this cell to deuterium exchange in glyceraldehyde‐3‐phosphate dehydrogenase reveals a class of H‐atoms highly resistant to deuteration, which is consistent with a previous infrared study on this protein. Copyright © 2009 John Wiley & Sons, Ltd.
Electrochemical and in situ SERS spectroelectrochemical investigations of 4‐methyl‐4H‐1, 2, 4‐triazole‐3‐thiol monolayers at a silver electrode
Authors: Sun Yiping , Song Wei , Zhu Xuan , Zhang Rui , Pang Qiuyi , Zhang Zongrang , Yang Haifeng
Published: April 2009

Electrochemically anticorrosive behavior of 4‐methyl‐4H‐1, 2, 4‐triazole‐3‐thiol (MTTL) self‐assembled monolayers (SAMs) on the silver electrode was studied by means of electrochemical impedance spectroscopy (EIS) and polarization measurements. The promising inhibition effect of the MTTL for silver had been affirmed. Results of surface‐enhanced Raman scattering (SERS) experiments indicated that the MTTL molecule in a tilted orientation was self‐assembled on the silver surface through S6 and N2 atoms to form monolayers. An in situ electrochemical SERS experiment implied the changes of adsorption fashion of MTTL momolayers on the silver surface with the potential shifted to more negative direction. Copyright © 2009 John Wiley & Sons, Ltd.
Fibroblast growth factor 18 gives growth and directional cues to airway cartilage
Authors: Elluru Ravindhra G. , Thompson Felisa , Reece Alisa
Published: April 2009

Objectives/Hypothesis:

The majority of congenital airway anomalies arise from deficits in the respiratory tract cartilage, emphasizing the importance of this cartilage to the form and function of the upper airway. The primary objective of this study was to characterize molecular mechanisms that regulate rate and direction of chondrocyte growth in the larynx and trachea. Our hypothesis for this study was that fibroblast growth factor 18 (FGF18) provides proliferative and directional cues to the developing laryngeal and tracheal cartilage in the mouse by up‐regulating the cartilage‐specifying gene, Sox9.

Study Design:

Molecular genetic and histological analyses of gene expression and cartilage growth in a mouse model.

Methods:

Controlled mating of wild‐type FVB/N (Friend Virus B‐type/NIH mouse) mice and FGF18 overexpressing mice were carried out, and embryos ranging from embryonic (E) day 10.5 to E18.5 were obtained. The respiratory tract, including the larynx, trachea, and lung, was removed through meticulous dissection, and subjected to whole‐mount in situ hybridization with RNA probes, or was sectioned and subjected to immunohistochemistry. Respiratory tracts from FVB/N mice were grown in culture in the presence of exogenous FGF18 or known inhibitors of the FGF pathway, and then subjected to quantitative reverse transcriptase polymerase chain reaction to measure the expression of cartilage‐specific genes.

Results:

The upper respiratory tract begins as a simple out‐pouching from the ventral foregut endoderm at E10.5. The chondrocytes that form the cartilaginous structures of the upper respiratory tract are located at the junction of the respiratory tract out‐pouching and the ventral foregut endoderm. This population of chondrocytes then undergoes directional proliferation to eventually assume the mature three‐dimensional configuration of the upper respiratory tract cartilaginous framework. Immunohistochemical localization of extracellular signal‐regulated kinases, a known modulator of FGF signaling, demonstrated the presence of this enzyme at the periphery of growing cartilage. Explants of larynx‐trachea‐lung grown in culture with exogenous FGF18 demonstrated hyperplastic growth and directed growth towards the FGF18 source. Finally, both FGF18 overexpressing tracheas and tracheas cultured with exogenous FGF18 demonstrated increased expression of the cartilage‐specifying gene, Sox9.

Conclusions:

FGF18 provided both directional and proliferative cues to chondrocytes in the developing upper respiratory tract. FGF18 exerted this effect on developing chondrocytes by up‐regulating Sox9 expression. Laryngoscope, 2009
Transoral trans‐stomal microdebrider excision of tracheal papillomatosis
Authors: Thorne Marc C. , Zur Karen B.
Published: April 2009

Objectives:

To describe a technique for surgical removal of recurrent respiratory papilloma in the distal trachea in patients with an indwelling tracheostomy tube.

Methods:

A transoral trans‐stomal technique for removal of distal tracheal papilloma using a modified ventilating bronchoscope setup and a microdebrider with a rotatable Skimmer blade (XOMED Products, Jacksonville, Florida, USA).

Results:

Surgical removal of papillomas in the distal trachea is a challenging procedure, involving potentially competing demands for visualization, instrumentation, and ventilation. Previously described methods for management of these challenging cases provide limited ability to deliver continuous oxygenation and ventilation during the procedure. The transoral trans‐stomal technique overcomes these limitations in patients who have an existing tracheostomy.

Conclusions:

This technique allows for precise removal of papilloma in the distal trachea, while providing for excellent visualization and continuous oxygenation and ventilation of the patient. Laryngoscope, 2009
Combined approach technique for the management of large salivary stones
Authors: Walvekar Rohan R. , Bomeli Steven R. , Carrau Ricardo L. , Schaitkin Barry
Published: April 2009

Objectives/Hypothesis:

To review our experience with the combined approach, which includes an internal (endoscopic) and open approach for the management of large salivary stones.

Study design:

Retrospective.

Methods:

Clinical data was reviewed on patients who underwent combined approach for large salivary stones from July 2005 to August 2008 under an institutional review board approved protocol.

Results:

Of 106 patients who underwent sialendoscopy, 19 patients (18%) had 20 combined procedures. Thirteen patients (68%) were women and six men (32%) with a mean age of 52 years (range, 15–69 years). Operative times were shorter for submandibular stones (mean, 90 minutes) as compared to parotid stones (mean, 133 minutes). Stone removal was successful in 90% (18/20) with no major complications and minor complications in four patients (20%).

Conclusions:

The combined procedure allows complete removal of large or impacted sialoliths without the need for removal of the entire gland with acceptable complication rates. We also recommend consenting patients for this approach when a difficult endoscopic removal is anticipated. Laryngoscope, 2009
Revision endoscopic sinus surgery in children
Authors: Ramadan Hassan H.
Published: April 2009

Objectives/Hypothesis:

Revision endoscopic sinus surgery (ESS) in children is uncommon. Causes of failure, however, are not very well delineated. The purpose of this study was to evaluate surgical causes of failure in children after ESS.

Study Design:

A retrospective review of children who had ESS at a tertiary children's referral center between 1993 and 2005 for chronic rhinosinusitis.

Methods:

ESS was performed on 243 children. Children with cystic fibrosis, immune deficiency/suppression, and ciliary abnormalities were excluded because the reasons of failure in those children are well known. Data were available on 176 children with at least one year of follow‐up.

Results:

Twenty‐three (13%) children required revision. The most common finding was adhesions in 57%, followed by maxillary sinus ostium stenosis or missed maxillary sinus ostium in 52% of the cases. In 39% of the cases, there was recurrent disease in the sinuses that were operated on initially. Interestingly, however, we found that in 26% surgery was needed because of disease that was present in nonoperated sinuses during the primary ESS. A deviated septum and a mucocele were the cause of failure in 17% and 13% of the patients, respectively. Presence of asthma and younger age contributed to the failure in some of these children.

Conclusions:

Adhesions and a scarred, narrow maxillary sinus ostium were the most common cause of failure in children after ESS. Steps taken during surgery may be required to help reduce the need for revision in particular for younger asthmatic children. Laryngoscope, 2009
Traumatic stapes fracture with rotation and subluxation into the vestibule and pneumolabyrinth
Authors: Ederies Ash , Yuen Heng‐Wai , Chen Joseph M. , Aviv Richard I. , Symons Sean P.
Published: April 2009

A 41‐year‐old man presented after forceful penetrating ear injury. He had incapacitating vestibular symptoms. Computed tomography revealed pneumolabyrinth with a fractured stapes that was >90° rotated and subluxed into the vestibule, such that the crura and capitulum could be seen in the vestibule. Surgical repair reversed the vestibular symptoms, but there was persistent hearing loss. Stapes fractures are unusual and rarely associated with subluxation into the vestibule. When this does occur, there is usually simple footplate depression. This case demonstrates a rare stapes fracture with pneumolabyrinth and >90 degrees stapes rotation, then subluxation into the vestibule. Laryngoscope, 2009
The enigmatic trigeminal caroticodural fold
Authors: Pensak Myles L. , Kerr Robert G. , Leung Randal , Keller Jeffrey T.
Published: April 2009

Objectives/Hypothesis:

We describe our cadaveric dissections and clinical findings that address anterior and ventral limitations imposed by the trigeminal nerve. Particularly, we identify the trigeminal caroticodural fold, the vestment of dura that traverses the space between the nerve and the internal carotid artery. We address the effect of mobilization of this fold to optimize access in Kawase's space when approaching the clivus and posterior fossa.

Methods:

Histological study and cadaveric dissections were performed to examine this regional anatomy. Our clinical series (2002 to 2007) includes 30 patients who underwent anterior petrosectomy as part of more complex approaches for lesions of the skull base.

Results:

Histological and dissection specimens showed a dense fibrous confluence lateral to the trigeminal ganglion and portions of the trigeminal nerve that we called the trigeminal caroticodural fold. This fold was prominent in 18 patients, ill‐defined in six, and absent in six patients. Incision of the trigeminal caroticodural fold permitted between 1 mm and 3 mm of additional exposure for drilling in Kawase's space without direct trauma to V3.

Conclusions:

Our study highlights the existence of a dural tethering of the trigeminal nerve and ganglion relevant to surgical exposure of Kawase's space. The regional dural anatomy that contributes to the trigeminal caroticodural fold is complex with subtle variances. We suggest that identification of this fold and its sharp dissection allows mobilization of the trigeminal ganglion and nerve without violation of V3, and ultimately can improve the transpetrosal access to the upper clivus and posterior fossa via this corridor. Laryngoscope, 2009
Malakoplakia of the frontal and ethmoid sinuses mimicking a mucocele
Authors: Soler Zachary M. , Sauer David , Smith Timothy L.
Published: April 2009

Malakoplakia is a rare, chronic inflammatory condition characterized by defective macrophage function. The majority of cases involve the genitourinary tract, but isolated cases have been reported from other organ systems including one prior report involving the maxillary sinus. We present a case of malakoplakia expanding the frontal and ethmoid sinuses mimicking a mucocele at presentation. The diagnosis was made at the time of surgery based on the histopathologic finding of von Hasemann cells and Michaelis‐Guttmann bodies. Sinus‐specific clinical aspects will be discussed including diagnostic and treatment considerations. Laryngoscope, 2009
T‐cell lymphoproliferative disorder following mycophenolate treatment for myasthenia gravis
Authors: Dubal Dena B. , Mueller Sabine , Ruben Beth S. , Engstrom John W. , Josephson S. Andrew
Published: April 2009

Immunosuppressive therapies are critical in the management of numerous conditions including myasthenia gravis. Mycophenolate mofetil is a widely used, oral immunosuppressive agent that is considered to have few adverse effects compared with similar drugs. We report the case of a patient who developed T‐cell lymphoproliferative lesions following long‐term treatment with mycophenolate mofetil and prednisone for myasthenia gravis. The lesions resolved following cessation of the treatment. This case highlights a serious complication of a commonly used drug. Muscle Nerve, 2009
Appointments to boards and committees via lottery, a pathway to fairness and diversity
Authors: Carson Lyn , Lubensky Ron
Published: April 2009

Public appointments for committees or boards can be controversial due to cronyism or pandering to demands of noisy or powerful interest groups. One relatively unexplored method for selecting committee or board members is random selection which has advantages beyond interrupting cronyism. This paper canvasses the strengths and weaknesses of an unusual selection method and makes a case for the use of a lottery as a robust process that will lend legitimacy and credibility to committee or board governance.

Copyright © 2009 John Wiley & Sons, Ltd.
Quantitative signal detection using spontaneous ADR reporting
Authors: Bate A. , Evans S. J. W.
Published: April 2009

Quantitative methods are increasingly used to analyse spontaneous reports. We describe the core concepts behind the most common methods, the proportional reporting ratio (PRR), reporting odds ratio (ROR), information component (IC) and empirical Bayes geometric mean (EBGM). We discuss the role of Bayesian shrinkage in screening spontaneous reports, the importance of changes over time in screening the properties of the measures. Additionally we discuss three major areas of controversy and ongoing research: stratification, method evaluation and implementation. Finally we give some suggestions as to where emerging research is likely to lead. Copyright © 2009 John Wiley & Sons, Ltd.
Drug‐induced torsades de pointes: data mining of the public version of the FDA Adverse Event Reporting System (AERS)
Authors: Poluzzi Elisabetta , Raschi Emanuel , Moretti Ugo , De Ponti Fabrizio
Published: April 2009

Aims

To investigate spontaneous reports of TdP present in the public version of the FDA Adverse Event Reporting System (AERS) in the light of what is already known on their TdP‐liability.

Methods

Reports of TdP from January 2004 through December 2007 were retrieved from the public version of the AERS database. All reports were selected from REACTION files and the relevant suspected and/or interacting drugs were identified from DRUG files. Qualitative analysis was performed by the case/non‐case method. Cases were represented by TdP reports, whereas non‐cases were all reports of adverse drug reactions other than TdP. Quantitative analysis was assessed by calculating the crude and adjusted reporting odds ratio (ROR), as a measure of disproportionality, with the 95% confidence interval.

Results

Reports of TdP were 1665 over a 4‐year period, involving 376 active substances. Thirty‐five drugs with at least 10 reports were identified: amiodarone and methadone were associated with the highest number of cases (113 and 83 respectively) and most of the other reports were ascribable to antibacterials, antidepressants and antipsychotics; remarkable differences in number of cases and ROR were present among agents within each therapeutic class. A disproportionate reporting was also observed for other compounds such as donepezil, famotidine and mitoxantrone.

Conclusions

Large spontaneous reporting databases represent an important source for signal detection of rare adverse drug reactions (ADR), such as TdP. The number of reports associated to donepezil, famotidine and mitoxantrone could be considered unexpected on the basis of current evidence and needs further investigations on their true TdP‐liability. Copyright © 2009 John Wiley & Sons, Ltd.
Characterization of molecular markers indicative of cervical cancer progression
Authors: Arnouk Hilal , Merkley Mark A. , Podolsky Robert H. , Stöppler Hubert , Santos Carlos , Álvarez Manuel , Mariategui Julio , Ferris Daron , Lee Jeffrey R. , Dynan William S.
Published: April 2009

Cervical cancer originates with human papillomavirus (HPV) infection and progresses via histologically defined premalignant stages. Here we compare normal cervical epithelium and patient‐matched high‐grade squamous intraepithelial lesions (HSIL) with cervical carcinoma tissue from the same patient population (n = 10 per group). Specimens were analyzed by combined laser capture microdissection and 2‐D DIGE. Significant expression changes were seen with 53 spots resulting in identification of 23 unique proteins at the molecular level. These include eight that uniquely distinguish normal epithelium and HSIL and four that uniquely distinguish HSIL and carcinoma. In addition, one protein, cornulin, distinguishes all three states. Other identified proteins included differentiation markers, oncogene DJ‐1, serpins, stress and interferon‐responsive proteins, detoxifying enzymes, and serum transporters. A literature review, performed for all identified proteins, allowed most changes to be assigned to one of three causes: direct or indirect HPV oncoprotein interactions, growth selection during latency, or interactions in the lesion microenvironment. Selected findings were confirmed by immunohistochemistry using either frozen sections from the same cohort or formalin fixed paraffin embedded samples from a tissue microarray. Novel markers described here have potential applications for increasing the predictive value of current screening methods.
Preparation and Characterization of Energetic Nanocomposites of Organic Gel – Inorganic Oxidizers
Authors: Cudziło Stanisław , Kiciński Wojciech
Published: April 2009

Two types of polymeric sols, resorcinol‐formaldehyde (RF) and resorcinol‐furfural (RFur), were mixed in a water‐containing medium with aqueous solutions of inorganic salts: NH4ClO4, Mg(ClO4)2, and NH4NO3. After gelation and an ambient pressure drying, hybrid nanocomposites with properties of energetic materials were obtained. It was stated that salt concentration and addition of a second solvent (e.g., methanol or N,N‐dimethylformamide) to the mixture of reagents have crucial meaning for gel formation. In the case when only water was used, the mixture of organic sol/inorganic salt did not transfer from sol to gel, and precipitates were formed. Conventional drying of wet gelled composites leads to rigid material called xerogels. The RF xerogels are red and RFur xerogels are black. Typically, xerogels are transparent at low salt concentration (below 30%). The microstructure, morphology, and some other properties of chosen composites were studied by means of HR SEM, AFM, XRD, DTA/TG, and N2 adsorption isotherm techniques. SEM observation revealed that sizes of the oxidizer particles vary from less than 100 nm to ca. 1000 nm. XRD analyses also confirmed the presence of nanometer‐sized crystals of oxidizers in some formulations. The specific surface area of polymeric matrix/oxidizer composites was found to be in the range from 0.002 to 0.3 m2 g−1. After removing the salt from the composites (by extraction with boiling water), the specific surface area grows even up to 210 m2 g−1. TG/DTA analyses showed that the tested composites decompose as typical energetic materials. If pre‐heated and exposed to flame, some of them (especially RF/Mg(ClO4)2  composites) undergo violent deflagration with loud sound and flash effect.
Ein prototypisches Kunststoff‐Faltwerk mit neuartiger Fügetechnologie
Authors: Engelsmann Stephan , Spalding Valerie
Published: April 2009

Ein prototypisches Kunststoff‐Faltwerk ist von der Klasse für Konstruktives Entwerfen und Tragwerkslehre der Staatlichen Akademie der Bildenden Künste Stuttgart entwickelt und in Eigenarbeit realisiert worden. Ein hochleistungsfähiges Tragwerkskonzept mit komplexer Geometrie, ein innovativer und hochwertiger Werkstoff und eine neu entwickelte Fügetechnologie sind die besonderen Kennzeichen des spektakulären Experimentalbaus. Der Beitrag beschreibt die Objektplanung, die Tragwerksplanung sowie die Herstellung und Montage des Kunststoff‐Faltwerks.
Nanoresolution interface studies in thin films by synchrotron x‐ray diffraction and by using x‐ray waveguide structure
Authors: Erdélyi Z. , Cserháti C. , Csik A. , Daróczi L. , Langer G. A. , Balogh Z. , Varga M. , Beke D. L. , Zizak I. , Erko A.
Published: April 2009

In the last years we performed several measurements with synchrotron radiation of several facilities to reveal interesting interface phenomena on the nanoscale. We used both x‐ray diffraction1, 2 (XRD) and spectrometry techniques. In this paper, we briefly summarize the results obtained from diffraction measurements, which lead us to our recent grazing incidence x‐ray fluorescence analysis (GIXRF) and extended x‐ray absorption fine structure (EXAFS) experiments.

We show how a combination of experimental methods of GIXRF analysis and EXAFS spectroscopy in fluorescence detection with x‐ray standing waves (XSW) technique was applied for the depth profiling of a‐Si/Co/a‐Si layers with nanometer resolution to monitor the growth of CoSi intermetallic phase. The investigated layers were placed into the waveguide structure formed by two Ta films to increase sensitivity and accuracy of the measurements. Copyright © 2009 John Wiley & Sons, Ltd.
Capturing the magic: Assessing the quality of youth mentoring relationships
Authors: Deutsch Nancy L. , Spencer Renée
Published: April 2009

Mentoring programs pose some special challenges for quality assessment because they operate at two levels: that of the dyadic relationship and that of the program. Fully assessing the quality of youth mentoring relationships requires understanding the characteristics and processes of individual relationships, which are the point of service for mentoring. Yet we also must consider the program components that support their development. A number of factors have been indicated to contribute to quality mentoring relationships, including frequency and consistency of contact, feelings of connection between mentor and protégé, and the mentor's approach. Program features linked with quality relationships include mentor screening and training and expectations for frequency of contact. Assessing the quality of the relationship directly requires measuring both the mentor's and protégé's perceptions of important dimensions of the relationship, such as goals, engagement, and closeness. Single‐point‐in‐time surveys or interviews, using both validated measures and open‐ended questions, may be used as tools for assessing individual relationships at the conclusion of programs. Short surveys, logs, and observations may be useful for periodic or ongoing assessment of quality for support and intervention purposes. Focus groups and surveys of mentors may also provide useful information for assessing program components needed to support the development and maintenance of high quality relationships. The benefits and drawbacks of each of these methods for assessing relational quality are discussed. Mentoring programs are provided with references for specific tools that may be used to assess relational quality.
The quest for quality: Recent developments and future directions for the out‐of‐school‐time field
Authors: Yohalem Nicole , Granger Robert C. , Pittman Karen J.
Published: April 2009

Understanding how to assess and improve what happens within out‐of‐school‐time (OST) programs is a critical challenge facing the field. This article explores key developments related to the issue of quality in the OST field during the past several years and then looks ahead at opportunities for future progress. From a practice perspective, one of the most notable recent developments is the proliferation of intentional, systemic efforts to improve program quality. From a policy perspective, discussions related to quality within the OST field reflect broader trends within human services and education toward increased accountability. In addition to holding systems accountable for producing client outcomes, there is an emerging trend toward holding systems and programs accountable for what it is they do with clients. Funders are increasingly focused on quality, and many now express specific expectations related to quality assessment for grantees. On the research side, there is increased interest among social science researchers to better understand OST settings, including a push to develop and refine point‐of‐service measures that can help researchers capture data on the specific practices that drive youth outcomes.
These promising developments position the field to evolve in some important ways in the coming years. In particular, there is an opportunity to refine and expand approaches to quality improvement using lessons from practice and research. From a policy perspective, quality can become further embedded in the accountability movement in ways that support program improvement by focusing attention on and directing resources toward the point of service.
Hydride Formation in the Intermetallic Compounds CePd3 and CeRh3
Authors: Kohlmann Holger , Müller Frank , Stöwe Klaus , Zalga Arturas , Beck Horst P.
Published: April 2009

The intermetallic compounds CePd3 and CeRh3 were hydrogenated at hydrogen pressures up to 24 MPa and temperatures up to 540 K, and investigated by X‐ray and neutron powder diffraction and X‐ray photoelectron spectroscopy (XPS). Both compounds retain their AuCu3 type arrangement upon hydrogen uptake. The cubic lattice parameters increase from 412.5(1) and 402.57(2) pm in CePd3 and CeRh3, respectively, to 413.5(1) and 406.27(3) pm in the corresponding hydrides. In contrast to the rhodium compound CePd3Hx forms only under high pressure and room temperature and releases hydrogen quickly in air. From neutron powder diffraction on CeRh3D0.84 deuterium atoms were found to occupy 84.4(8) % of octahedral interstices formed solely by rhodium atoms, [Rh6], in a statistical fashion, resulting in a deficient cubic anti‐perovskite type structure (space group $Pm{\bar 3}m$ (No. 221), a = 407.248(7) pm at T = 299(2) K). Rhodium‐deuterium (203.62(1) pm) and cerium‐deuterium distances (352.69(1) pm) are consistent with typical interatomic distances in other hydrides. XPS measurements reveal mixed valency in CePd3.
A Complex Cesiumchloride: Cs5[AgCl2][CoCl4]Cl2
Authors: Fastje Oliver , Möller Angela
Published: April 2009

Cs5[AgCl2][CoCl4]Cl2 has been obtained as blue single crystals and the crystal structure has been determined from X‐ray diffraction data [I4/mcm, Z = 4, a = 919.15(8) pm, c = 2375.9(3) pm]. The characteristic structural features are isolated complex chlorido‐anions, [AgCl2]– and [CoCl4]2–, as well as non‐coordinating Cl– in this cesium‐rich compound. The title compound has been further studied by spectroscopic methods in the infrared and UV/Vis region and a description of the electronic structure for the chromophore, [CoCl4]2–, within the angular‐overlap‐model (AOM) is given.
The role of Allee effects in gypsy moth,Lymantria dispar(L.), invasions
Authors: Tobin Patrick C. , Robinet Christelle , Johnson Derek M. , Whitmire Stefanie L. , Bjørnstad Ottar N. , Liebhold Andrew M.
Published: April 2009

Allee effects have been applied historically in efforts to understand the low‐density population dynamics of rare and endangered species. Many biological invasions likewise experience the phenomenon of decreasing population growth rates at low population densities because most founding populations of introduced nonnative species occur at low densities. In range expansion of established species, the initial colonizers of habitat beyond the organism's current range are usually at low density, and thus could be subject to Allee dynamics. There has been consistent empirical and theoretical evidence demonstrating, and in some cases quantifying, the role of Allee dynamics in the gypsy moth,Lymantria dispar(L.), invasion of North America. In this review, we examine the potential causes of the Allee effect in the gypsy moth and highlight the importance of mate‐finding failure as a primary mechanism behind an Allee effect, while the degree to which generalist predators induce an Allee effect remains unclear. We then explore the role of Allee effects in the establishment and spread dynamics of the gypsy moth system, which conceptually could serve as a model system for understanding how Allee effects manifest themselves in the dynamics of biological invasions.
Evidence for a warmer period during the 12th and 13th centuries AD from chironomid assemblages in Southampton Island, Nunavut, Canada
Authors: Rolland Nicolas , Larocque Isabelle , Francus Pierre , Pienitz Reinhard , Laperrière Laurence
Published: April 2009

This study presents the Late-Holocene evolution of a northern Southampton Island (Nunavut, Canada) lake, using fossil chironomids supported by sedimentological evidences (XRF, grain size and CNS). All proxies revealed a relatively stable environment during the last millennium with short-lived events driving changes in the entire lake ecosystem. The chironomid-based paleotemperatures revealed variations of significant amplitude coincident with changes in the sediment density and chemical composition of the core. Higher temperature intervals were generally correlated to lower sediment density with higher chironomid concentration and diversity. Higher temperatures were recorded from cal yr AD 1160 to AD 1360, which may correspond to the Medieval Warm Period. Between cal yr AD 1360 and AD 1700, lower temperatures were probably related to a Little Ice Age event. This study presents new information on the timing of known climatic events which will refine our knowledge of the paleoclimate and climatic models of the Foxe Basin region. It also provides a new framework for the evolution of such freshwater ecosystems under the “Anthropocene” and underlines the importance of including sedimentological proxies when interpreting chironomid remains as this combined approach provides an extended overview of the past hydrological and geochemical changes and their impacts on lake biota.
Risikofaktoren der koronaren Herzkrankheit
Authors: Hof Danielle , von Eckardstein Arnold
Published: April 2009

Die durch Atherosklerose verursachte Koronare Herzkrankheit (KHK) ist die häufigste Todesursache in den Industrienationen, sodass ihre Prävention eine wichtige medizinische Aufgabe ist. Klassische Risikofaktoren, wie z.B. Alter, Rauchen und Cholesterinspiegel erlauben vor allem durch Anwendung von Algorithmen oder Scores das Risiko für ein kardiovaskuläres Ereignis bei asymptomatischen Patienten in den nächsten zehn Jahren abzuschätzen. Allerdings sind die gegenwärtigen Methoden vor allem in Bezug auf ihre prognostische Sensitivität und positive prädiktive Wertigkeit eingeschränkt. Deswegen werden neue Risikofaktoren und Biomarker gesucht, um die Risikostratifizierung zu verbessern. Diese Übersicht beschreibt die Risikostratifizierung der KHK und einige wichtige neue Biomarker.
Atmospheric forcing of the Beaufort Sea ice gyre: Surface pressure climatology and sea ice motion
Authors: Asplin Matthew G. , Lukovich Jennifer V. , Barber David G.
Published: April 2009

The Beaufort Gyre (BG) typically rotates anticyclonically and exerts an important control on Arctic Sea ice dynamics. Previous studies have shown reversals in the BG to rotate cyclonically during summer months and, in recent decades, throughout the annual cycle. In this investigation, we explore the synoptic climatology of atmospheric forcing and its relationship to sea ice motion and BG reversals. A catalog of daily synoptic weather types is generated for the Beaufort Sea Region covering the period 1979 to 2006 using NCEP/NCAR reanalysis mean sea level pressure data, principle components, and k‐means cluster analyses. Mean synoptic type frequency, persistence, and duration values are calculated for each synoptic type and contrasted between the summer and winter seasons. Daily synoptic types are linked to changes in sea ice vorticity by using correlation analysis on lagged sea ice vorticity data. Lag correlations are found between synoptic types and sea ice vorticity smoothed over a 12‐week running mean and show that cyclonic types, which promote southerly or easterly atmospheric circulation over the southern Beaufort Sea, commonly precede summer reversals. Furthermore, significant seasonal within‐type variability in sea ice vorticity is detected within the synoptic types illustrating the importance of seasonal variability on these processes.
Enhanced pre‐monsoon warming over the Himalayan‐Gangetic region from 1979 to 2007
Authors: Gautam R. , Hsu N. C. , Lau K.‐M. , Tsay S.‐C. , Kafatos M.
Published: April 2009

Fundamental to the onset of the Indian Summer Monsoon is the land‐sea thermal gradient from the Indian Ocean to the Himalayas‐Tibetan Plateau (HTP). The timing of the onset is strongly controlled by the meridional tropospheric temperature gradient due to the rapid pre‐monsoon heating of the HTP compared to the relatively cooler Indian Ocean. Analysis of tropospheric temperatures from the longest available record of microwave satellite measurements reveals widespread warming over the Himalayan‐Gangetic region and consequent strengthening of the land‐sea thermal gradient. This trend is most pronounced in the pre‐monsoon season, resulting in a warming of 2.7°C in the 29‐year record (1979–2007), when this region is strongly influenced by dust aerosols at elevated altitudes. The enhanced tropospheric warming is accompanied by increased atmospheric loading of absorbing aerosols, particularly vertically extended dust aerosols, raising the possibility that aerosol solar heating has amplified the seasonal warming and in turn strengthened the land‐sea gradient.
Neuroinflammation Extends Brain Tissue at Risk to Vital Peri-Infarct Tissue: A Double Tracer [11C]PK11195- and [18F]FDG-PET Study
Authors: Schroeter Michael , Dennin Maria A , Walberer Maureen , Backes Heiko , Neumaier Bernd , Fink Gereon R , Graf Rudolf
Published: April 2009

Focal cerebral ischemia elicits strong inflammatory responses involving activation of resident microglia and recruitment of monocytes/macrophages. These cells express peripheral benzodiazepine receptors (PBRs) and can be visualized by positron emission tomography (PET) using [11C]PK11195 that selectively binds to PBRs. Earlier research suggests that transient ischemia in rats induces increased [11C]PK11195 binding within the infarct core. In this study, we investigated the expression of PBRs during permanent ischemia in rats. Permanent cerebral ischemia was induced by injection of macrospheres into the middle cerebral artery. Multimodal imaging 7 days after ischemia comprised (1) magnetic resonance imaging that assessed the extent of infarcts; (2) [18F]-2-fluoro-2-deoxy-d-glucose ([18F]FDG)-PET characterizing cerebral glucose transport and metabolism; and (3) [11C]PK11195-PET detecting neuroinflammation. Immunohistochemistry verified ischemic damage and neuroinflammatory processes. Contrasting with earlier data for transient ischemia, no [11C]PK11195 binding was found in the infarct core. Rather, permanent ischemia caused increased [11C]PK11195 binding in the normoperfused peri-infarct zone (mean standard uptake value (SUV): 1.93 ± 0.49), colocalizing with a 60% increase in the [18F]FDG metabolic rate constant with accumulated activated microglia and macrophages. These results suggest that after permanent focal ischemia, neuroinflammation occurring in the normoperfused peri-infarct zone goes along with increased energy demand, therefore extending the tissue at risk to areas adjacent to the infarct.
Building and Applying a Human Cognition Model for Visual Analytics
Authors: Green Tera Marie , Ribarsky William , Fisher Brian
Published: April 2009

It is well known that visual analytics addresses the difficulty of evaluating and processing large quantities of information. Less often discussed are the increasingly complex analytic and reasoning processes that must be applied in order to accomplish that goal. Success of the visual analytics approach will require us to develop new visualization models that predict how computational processes might facilitate human insight and guide the flow of human reasoning. In this paper, we seek to advance visualization methods by proposing a framework for human ‘higher cognition’ that extends more familiar perceptual models. Based on this approach, we suggest guidelines for the development of visual interfaces that better integrate complementary capabilities of humans and computers. Although many of these recommendations are novel, some can be found in existing visual analytics applications. In the latter case, much of the value of our contribution lies in the deeper rationale that the model provides for those principles. Lastly, we assess these visual analytics guidelines through the evaluation of several visualization examples.
Magnetic properties of plutonium and Pu compounds
Authors: Havela Ladislav , Shick Alexander , Gouder Thomas
Published: April 2009

Occurrence of magnetic order on the basis of plutonium can be captured by LDA+U calculations. Systematic investigation of diverse Pu compounds reveals that the 5f occupancy plays a key role. If the 5f states are populated by more than approximately 5.3 electrons, the Pu magnetism vanishes. For comparison with valence-band photoemission spectra, the Hubbard I method was used. It shows consistently higher 5f5 final-state multiplet originating from the 5f6 admixture in the ground state for those compounds which are nonmagnetic. The 5f occupancy can reach 5.6–5.7 for Pu monochalcogenides.
Competing failure mechanisms in thin films: Application to layer transfer
Authors: Ponson L. , Diest K. , Atwater H. A. , Ravichandran G. , Bhattacharya K.
Published: April 2009

We investigate the origin of transverse cracks often observed in thin films obtained by the layer transfer technique. During this process, two crystals bonded to each other containing a weak plane produced by ion implantation are heated to let a thin layer of one of the material on the other. The level of stress imposed on the film during the heating phase due to the mismatch of thermal expansion coefficients of the substrate and the film is shown to be the dominent factor in determining the quality of the transferred layer. In particular, it is shown that if the film is submitted to a tensile stress, the microcracks produced by ion implantation are not stable and deviate from the plane of implantation making the layer transfer process impossible. However, if the compressive stress exceeds a threshold value, after layer transfer, the film can buckle and delaminate, leading to transverse cracks induced by bending. As a result, we show that the imposed stress σm—or equivalently the heating temperature—must be within the range −σc<σm<0 to produce an intact thin film where σc depends on the interfacial fracture energy and the size of defects at the interface between film and substrate.
Sediment resuspension and erosion by vortex rings
Authors: Munro R. J. , Bethke N. , Dalziel S. B.
Published: April 2009

Particle resuspension and erosion induced by a vortex ring interacting with a sediment layer was investigated experimentally using flow visualization (particle image velocimetry), high-speed video, and a recently developed light attenuation method for measuring displacements in bed level. Near-spherical sediment particles were used throughout with relative densities of 1.2–7 and diameters (d) ranging between 90 and 1600 μm. Attention was focused on initially smooth, horizontal bedforms with the vortex ring aligned to approach the bed vertically. Interaction characteristics were investigated in terms of the dimensionless Shields parameter, defined using the vortex-ring propagation speed. The critical conditions for resuspension (whereby particles are only just resuspended) were determined as a function of particle Reynolds number (based on the particle settling velocity and d). The effects of viscous damping were found to be significant for d/δ<15, where δ denotes the viscous sublayer thickness. Measurements of bed deformation were obtained during the interaction period, for a range of impact conditions. The (azimuthal) mean crater profile is shown to be generally self-similar during the interaction period, except for the most energetic impacts and larger sediment types. Loss of similarity occurs when the local bed slope approaches the repose limit, leading to collapse. Erosion, deposition, and resuspension volumes are analyzed as a function interaction time, impact condition, and sediment size.