bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evolution in the management of facial nerve schwannoma
Authors: Wilkinson Eric P. , Hoa Michael , Slattery William H. , Fayad Jose N. , Friedman Rick A. , Schwartz Marc S. , Brackmann Derald E. 
Published: September 2011

AbstractObjective:To design a treatment algorithm based on experience with facial nerve schwannomas (FNS) over a 30‐year period.Study Design:Retrospective chart review.Method:Seventy‐nine patients with facial nerve schwannomas seen from 1979 through 2009 at a tertiary referral private otologic practice were categorized by treatment modality. Interventions included surgical resection with grafting, bony decompression, observation, or stereotactic radiation. Outcome measures included House‐Brackmann facial nerve grade before and after intervention as well as change in facial nerve grade, tumor size, involved segments of nerve, time to intervention.Results:Thirty‐seven patients (46.8%) ultimately underwent surgical excision with grafting or primary anastomosis, 21 (26.6%) underwent bony decompression alone, 15 (19.0%) were managed with observation only, and 6 (7.6%) had stereotactic radiation. Through 1995, 85% of cases had surgical resection and none had observation only. Of the 52 patients seen after 1995, 27% had surgical resection and grafting, 33% had bony decompression, 29% were managed with observation alone, and 11% had radiotherapy. Facial nerve grade was maintained or improved over the follow‐up period (mean time = 3.9 years) in 78.9% of the decompression group and 100% of the observation and radiation groups compared to 54.8% of the resection group (P ≤ .012).Conclusions:Surgical resection and grafting, once widely accepted and practiced, has in many cases given way to observation, bony decompression, or stereotactic radiation. A wide armamentarium of options is available to the neurotologist treating facial nerve schwannomas with the ability to preserve facial function for a longer period of time.
Injection of human mesenchymal stem cells improves healing of vocal folds after scar excision—A xenograft analysis
Authors: Svensson Bengt , Nagubothu Srinivasa R. , Cedervall Jessica , Chan Roger W. , Le Blanc Katrina , Kimura Miwako , Ährlund‐Richter Lars , Tolf Anna , Hertegård Stellan 
Published: September 2011

AbstractObjectives:Using a xenograft model the aim was to analyze if injection of human mesenchymal stem cells (hMSC) into the rabbit vocal fold (VF), after excision of an established scar, can improve the functional healing of the VF.Study Design:Prospective design with an experimental xenograft model.Methods:The VFs of 12 New Zealand rabbits were injured by a bilateral localized resection. After 9 weeks the scar after the resection was excised and hMSC were injected into the VFs. After another 10 weeks 10 VFs were dissected and stained for histology. Lamina propria thickness and relative content of collagen type I were measured. Viscoelasticity of 14 VFs at phonatory frequencies was quantified by a simple‐shear rheometer. The hMSC survival was determined using a human DNA specific reference probe, that is, FISH analysis.Results:The viscoelastic measurements, that is, dynamic viscosity and elastic shear modulus for the hMSC‐treated VFs, were found to be similar to those of normal controls and were significantly lower than those of untreated controls (P < .05). A significant reduction in lamina propria thickness was also shown for the hMSC treated VFs compared with the untreated VFs (P < .05). This histologic finding corresponded with the viscoelastic results. No hMSC survived 10 weeks after the injection.Conclusions:Human mesenchymal stem cells injected into the rabbit VF following the excision of a chronic scar, were found to enhance the functional healing of the VF with reduced lamina propria thickness and restored viscoelastic shear properties.
ORL emergencies boot camp: Using simulation to onboard residents
Authors: Malekzadeh Sonya , Malloy Kelly M. , Chu Eugenia E. , Tompkins Jared , Battista Alexis , Deutsch Ellen S. 
Published: September 2011

AbstractObjectives/Hypothesis:Incoming otolaryngology residents are expected to triage and manage airway, bleeding, and other emergencies with little prior experience. Simulation‐based education has become increasingly important as it provides tools to develop psychomotor skills and judgment early in residency, using realistic experiences while eliminating patient risk. We hypothesize that a Boot Camp course emphasizing basic otolaryngology management will increase participants' confidence and be perceived as useful in developing their knowledge, technical skills, self‐confidence, and improving clinical performance, both immediately and 6 months following the course.Study Design:Survey.Methods:A 1‐day Boot Camp was developed consisting of six technical skills stations (mask ventilation, intubation, flexible laryngoscopy, microlaryngoscopy/bronchoscopy, epistaxis control, and cricothyroidotomy); a session involving telephone inquiry triage, and two complex airway scenarios addressing medical management and emphasizing team leadership. Residents completed questionnaires before, immediately, and 6 months following course completion.Results:Thirty residents enrolled, 27 participated in the course, and 24 completed all three surveys. Previous experiences and confidence levels were variable; 26 of 30 (87%) identified emergency airway management as a concern before attending the course. A Fisher's exact test demonstrated improved confidence (P < .05) for every skill. An overwhelming majority of participants agreed or strongly agreed the intervention was useful in developing their knowledge, technical skills, self‐confidence, and improving clinical performance.Conclusions:An intensive, simulation‐based Boot Camp addressing airway, bleeding, and other otolaryngology emergencies was successful in improving junior otolaryngology residents' confidence and was perceived as useful in developing knowledge, technical skills, self‐confidence, and improving clinical performance.
Augmented image guidance improves skull base navigation and reduces task workload in trainees: A preclinical trial
Authors: Dixon Benjamin J. , Daly Michael J. , Chan Harley , Vescan Allan , Witterick Ian J. , Irish Jonathan C. 
Published: September 2011

AbstractObjectives/Hypothesis:Our group has developed an augmented image guidance system that incorporates intraoperative cone‐beam computed tomography (CBCT), virtual or augmented displays, and image registration. We assessed the potential benefits of augmented endoscopy derived from this system for use during skull base navigation. Specifically, we wished to evaluate target localization accuracy and the effect on task workload and confidence.Study Design:Prospective, sequential, paired preclinical trial.Methods:A single cadaver head underwent computed tomography, and critical structures were contoured. The specimen was reimaged after endoscopic dissection and deformable registration allowed contours to be displayed on postablation CBCT imaging. A real‐time virtual view including anatomical contours was provided parallel to the real endoscopic image. Twelve subjects were asked to endoscopically localize seven skull base landmarks in a conventional manner. The same exercise was then performed with augmented endoscopy. Precise three‐dimensional (3D) localization was recorded with a tracked probe. The NASA task load index was completed after each exercise. A short questionnaire was also administered.Results:The real‐time augmented image guidance system aided localization in 85% of responses and increased confidence in 97%. There was a significant reduction in mental demand, effort, and frustration when the technology was employed, with an increase in perceived performance (P < .05). Three dimensional navigational precision was improved for all landmarks.Conclusions:Real‐time augmented image‐guided surgery increases accuracy and confidence in trainee surgeons and decreases task workload during skull base navigation. This technology shows great promise in assisting in skull base surgery even for experienced surgeons.
Conscious change leadership: Achieving breakthrough results
Authors: Anderson Dean , Anderson Linda Ackerman 
Published: September 2011

AbstractTo drive organizational change that is “wildly successful,” leaders should look beyond change management and project management, the authors say. They explain why “conscious change leadership” is the answer. They guide readers to understanding change within three focus areas: content, people, and process. Furthermore, there are three types of change facing today's leaders: developmental, transitional, and transformational. Strategies are presented for how to consciously navigate transformational change. This is important, because “your success will be in direct correlation to your level of awareness and worldview.”
Toxicology and risk assessment of acrolein in food
Authors: Abraham Klaus , Andres Susanne , Palavinskas Richard , Berg Katharina , Appel Klaus E. , Lampen Alfonso 
Published: September 2011

AbstractAcrolein is an α,β‐unsaturated aldehyde formed by thermal treatment of animal and vegetable fats, carbohydrates and amino acids. In addition it is generated endogenously. As an electrophile, acrolein forms adducts with gluthathione and other cellular components and is therefore cytotoxic. Mutagenicity was shown in some in vitro tests. Acrolein forms different DNA adducts in vivo, but mutagenic and cancerogenous effects have not been demonstrated for oral exposure. In subchronic oral studies, local lesions were detected in the stomach of rats. Systemic effects have not been reported from basic studies. A WHO working group established a tolerable oral acrolein intake of 7.5 μg/kg body weight/day. Acrolein exposure via food cannot be assessed due to analytical difficulties and the lack of reliable content measurements. Human biomonitoring of an acrolein urinary metabolite allows rough estimates of acrolein exposure in the range of a few μg/kg body weight/day. High exposure could be ten times higher after the consumption of certain foods. Although the estimation of the dietary acrolein exposure is associated with uncertainties, it is concluded that a health risk seems to be unlikely.
Interaction of hydrated protons with octyl‐phenyl‐N,N‐diisobutylcarbamoylmethyl phosphine oxide (CMPO): NMR and theoretical study
Authors: Kříž Jaroslav , Dybal Jiří , Makrlík Emanuel , Vaňura Petr 
Published: September 2011

AbstractInteraction of octyl‐phenyl‐N,N‐diisobutylcarbamoylmethylphosphine oxide (CMPO, the ‘classical’ rare metal extraction agent) with fully ionized hydrated protons (HP) was studied in acetonitrile‐d3 using 1H, 13C, 31P NMR, PFG NMR and magnetic relaxation. The experimental results were confronted with high‐precision ab initio DFT calculations. Relative chemical shifts of NMR signals of CMPO (0.01 mol/L) under the presence of HP in the molar ratio β = 0–2.0 mol/mol show binding between CMPO and HP. Self‐diffusion measurements using 1H PFG NMR demonstrate that larger complexes with higher content of CMPO are generally formed at β < 0.75. Analyzing the collective dependence of 13C and 31P NMR chemical shifts on β by the use of program LETAGROP, we obtained very good fitting for the assumed coexistence of two complexes (CMPO)2·HP (C2) and CMPO.HP (C1). The logarithms of the respective stabilization constants log Ki were found to be 7.518 (C2) and 4.581 (C1). The system dynamics was studied by measuring the transverse 1H NMR relaxation using CPMG sequence with varying delays tp between the π pulses in the mixtures with β = 0.4–0.8. The following exchange correlation times were obtained: τ10 = 2.35 × 10−5, τ20 = 0.82 × 10−4, τ21 = 0.45 × 10−3s. The DFT calculations support the conclusion that the complexes C1 and C2 are the main species in the mixtures of CMPO with HP. They also agree with the NMR and FTIR observation that the main site to which H3O+ is bound is the PO group, whereas the amide group does not form a strong bond with the ion when excess water molecules are present. Copyright © 2011 John Wiley & Sons, Ltd.
Formyl migration product of chanoclavine‐I aldehyde in the presence of the old yellow enzyme FgaOx3 from Aspergillus fumigatus: a NMR structure elucidation
Authors: Xie Xiulan , Wallwey Christiane , Matuschek Marco , Steinbach Klaus , Li Shu‐Ming 
Published: September 2011

AbstractA previous study showed that together with the festuclavine synthase FgaFS, the old yellow enzyme FgaOx3 from Aspergillus fumigatus catalyzed the conversion of chanoclavine‐I aldehyde to festuclavine in the biosynthesis of ergot alkaloids. In the absence of FgaFS, a mixture containing two compounds with a ratio of 7:3 was detected in the enzyme assay of FgaOx3. NMR experiments including (DQF)‐COSY, HSQC, HMBC and NOESY identified their structures as E/Z isomers of N‐methyl‐N‐[(5R,10R)‐10‐(2‐oxo‐propyl)‐2,4,5,10‐tetrahydrobenzo[cd]indol‐5‐yl]formamide and proved the migration of the formyl group at C‐8 in chanoclavine I‐aldehyde to N‐6 in the identified products. Copyright © 2011 John Wiley & Sons, Ltd.
Family involvement in small, local nongovernmental organizations
Authors: Jakimow Tanya 
Published: September 2011

AbstractThe involvement of family members in nongovernmental organizations (NGOs) has been largely overlooked in the literature on the nonprofit and voluntary sector. This study draws on the family business literature to explore the main features of family involvement and the implications for organizational survival and effectiveness. It shows that the family is an important research variable. Exploring the NGO sector in India, the article demonstrates that family involvement can significantly influence the management of human and material resources, governance, and decision making. Although there are several advantages to family involvement, a large overlap of family and organization can threaten credibility and legitimacy. Family‐based NGOs must stress their value orientation to counter negative perceptions.
Patients' experiences of seeking health care for lower urinary tract symptoms
Authors: Welch Lisa C. , Taubenberger Simone , Tennstedt Sharon L. 
Published: September 2011

AbstractA gap between experiencing symptoms and receiving effective treatment persists for people with lower urinary tract symptoms (LUTS), even for those who seek health care. In order to better understand how patients experience treatment seeking for LUTS, we interviewed a racially diverse sample of 90 men and women with a range of LUTS about their experiences seeking care. Thematic analysis revealed that patients often disclosed urinary symptoms first to primary care providers during a general examination or a visit for another health problem. Patients seek provider assistance typically when symptoms have intensified or are causing worry, and a desire for treatment trumps potential embarrassment; among women patients, feeling comfortable with a provider also is important for disclosing LUTS. © 2011 Wiley Periodicals, Inc. Res Nurs Health 34:496–507, 2011
Determination of the amino acid sequence requirements for catalysis by the highly proficient orotidine monophosphate decarboxylase
Authors: Yuan Ji , Cardenas Ana Maria , Gilbert Hiram F. , Palzkill Timothy 
Published: September 2011

AbstractOrotidine 5′‐monophosphate decarboxylase (ODCase) catalyzes the decarboxylation of orotidine 5′‐monophosphate to uridine 5′‐monophosphate during pyrimidine nucleotide biosynthesis. This enzyme is one of the most proficient known, exhibiting a rate enhancement of over 17 orders of magnitude over the uncatalyzed rate. An interesting question is whether the high proficiency of ODCase is associated with a highly optimized sequence of active site residues. This question was addressed by randomizing 24 residue positions in and around the active site of the E. coli ODCase (pyrF) by site‐directed mutagenesis. The libraries of mutants were selected for function from a multicopy plasmid or by single‐copy replacement at the pyrF locus on the E. coli chromosome. Stringent sequence requirements for function were found for the mutants expressed from the chromosomal pyrF locus. Six positions were not tolerant of substitutions and several others accepted very limited substitutions. In contrast, all positions could be substituted to some extent when the library mutants were expressed from a multicopy plasmid. For the conserved quartet of charged residues Lys44‐Asp71‐Lys73‐Asp76, a cysteine substitution was found to provide function at positions 71 and 76. A lower pKa for both cysteine mutants supports a mechanism whereby the thiolate group of cysteine substitutes for the negatively charged aspartate side chain. The partial function mutants such as D71C and D76C exhibit reduced catalytic efficiency relative to wild type but nevertheless provide a rate enhancement of 15 orders of magnitude over the uncatalyzed rate indicating the catalytic proficiency of the enzyme is robust and tolerant of mutation.
A structural study of Hypocrea jecorina Cel5A
Authors: Lee Toni M. , Farrow Mary F. , Arnold Frances H. , Mayo Stephen L. 
Published: September 2011

AbstractInterest in generating lignocellulosic biofuels through enzymatic hydrolysis continues to rise as nonrenewable fossil fuels are depleted. The high cost of producing cellulases, hydrolytic enzymes that cleave cellulose into fermentable sugars, currently hinders economically viable biofuel production. Here, we report the crystal structure of a prevalent endoglucanase in the biofuels industry, Cel5A from the filamentous fungus Hypocrea jecorina. The structure reveals a general fold resembling that of the closest homolog with a high‐resolution structure, Cel5A from Thermoascus aurantiacus. Consistent with previously described endoglucanase structures, the H. jecorina Cel5A active site contains a primarily hydrophobic substrate binding groove and a series of hydrogen bond networks surrounding two catalytic glutamates. The reported structure, however, demonstrates stark differences between side‐chain identity, loop regions, and the number of disulfides. Such structural information may aid efforts to improve the stability of this protein for industrial use while maintaining enzymatic activity through revealing nonessential and immutable regions.
HLA‐DP2 binding prediction by molecular dynamics simulations
Authors: Doytchinova Irini , Petkov Peicho , Dimitrov Ivan , Atanasova Mariyana , Flower Darren R. 
Published: September 2011

AbstractMajor histocompatibility complex (MHC) II proteins bind peptide fragments derived from pathogen antigens and present them at the cell surface for recognition by T cells. MHC proteins are divided into Class I and Class II. Human MHC Class II alleles are grouped into three loci: HLA‐DP, HLA‐DQ, and HLA‐DR. They are involved in many autoimmune diseases. In contrast to HLA‐DR and HLA‐DQ proteins, the X‐ray structure of the HLA‐DP2 protein has been solved quite recently. In this study, we have used structure‐based molecular dynamics simulation to derive a tool for rapid and accurate virtual screening for the prediction of HLA‐DP2‐peptide binding. A combinatorial library of 247 peptides was built using the “single amino acid substitution” approach and docked into the HLA‐DP2 binding site. The complexes were simulated for 1 ns and the short range interaction energies (Lennard–Jones and Coulumb) were used as binding scores after normalization. The normalized values were collected into quantitative matrices (QMs) and their predictive abilities were validated on a large external test set. The validation shows that the best performing QM consisted of Lennard–Jones energies normalized over all positions for anchor residues only plus cross terms between anchor‐residues.
Temperature dependence of inner tube growth from ferrocene‐filled single‐walled carbon nanotubes
Authors: Liu Xianjie , Kuzmany Hans , Saito Takeshi , Pichler Thomas 
Published: September 2011

AbstractThe growth of inner tubes from ferrocene‐filled single‐walled carbon nanotubes was studied with Raman spectroscopy. Special attention was paid to inner tubes formation based on the annealing temperature and the outer tube diameter. Besides the presence of inner tubes radial breathing mode, a new Raman feature appears around 1250 cm−1, which is always related to the appearance of the inner tube. The thermal stability of the inner tube strongly depends on the outer tube diameter. The inner tube formed inside outer tube with 1 nm diameter is destructed at 1000 °C, but it can survive more than 1300 °C with outer tube diameter of about 1.6 nm. Furthermore, the splitting of G line and the shift of 2D line were discussed regarding to the appearance of inner tubes.
Contamination of silicon by iron at temperatures below 800 °C
Authors: Murphy J. D. , Falster R. J. 
Published: September 2011

AbstractIron‐related defects are deleterious in silicon‐based integrated circuits and photovoltaics, ruining devices and acting as strong recombination centres. Unless great care is taken, iron contamination will result from high temperature processing and so it is essential to understand the degree to which this can occur. Iron solubility data above ∼800 °C have been summarised by Istratov et al. (Appl. Phys. A 69, 13 (1999)), but many processes are performed at lower temperatures for which solubility data are scarce. We have studied iron contamination below ∼800 °C. Iron concentrations in intention‐ ally contaminated air‐annealed Czochralski silicon samples were determined from the change in minority carrier lifetime due to photodissociation of FeB pairs measured by quasi‐steady‐state photoconductance. In the ∼600 to 800 °C temperature range the iron concentration was found to vary according to $ 1.3 \times 10^{21} \; {\rm exp} \;\left (‐ { {1.8\;{\rm eV} } \over {kT} } \right)\;{\rm cm}^{‐3}. It is therefore the case that significantly more iron can dissolve in silicon at these temperatures than extrapolation of higher temperature data suggests, with the enhancement being by a factor of >20 at 600 °C. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A decoupled exponential random graph model for prediction of structure and attributes in temporal social networks
Authors: Ouzienko Vladimir , Guo Yuhong , Obradovic Zoran 
Published: September 2011

AbstractThe analysis of social networks often assumes time invariant scenario, while in practice actor attributes and links in such networks often evolve over time and are inextricably dependent on each other. In this article, we propose a new method to predict actor attributes and links in temporal networks. Our approach takes into account the attributes corresponding to the participating actors together with topological and structural changes of the network over time. This is achieved by building two conditional predictors to jointly infer links and actor attributes. The proposed prediction method was significantly more accurate than alternatives when evaluated on synthetic data sets and two well‐studied real‐life temporal social networks. In addition, the new algorithm is computationally more efficient than a related alternative scaling up linearly with the number of temporal observations and quadratically with the number of actors considered. © 2011 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 4: 470–486, 2011
A statistical model of signal–noise in scanning electron microscopy
Authors: Timischl F. , Date M. , Nemoto S. 
Published: September 2011

AbstractA statistical model describing signal‐noise generation and development along the signal formation process in a standard scanning electron microscope (SEM) using an Everhart–Thornley secondary electron detector is derived. Noise in the detector signal is modeled to originate from a cascade of five signal conversion stages. Based on the derived model, general conclusions are drawn concerning the total signal‐to‐noise ratio (SNR) at each stage, and the influence of each stage on the total SNR of the detector signal. The model is furthermore applied to a real‐world SEM, and verified by experimental data. SCANNING 34: 137–144, 2012. © 2011 Wiley Periodicals, Inc.