bluuebunny/crossref_metadata_2025 huggingface dataset:
Tandem Ionization Mass Spectrometry of Biomolecules
Authors: Zubarev R.A. , Nielsen M.L. , Budnik B.A.
Published: December 2007

The novel mass spectrometric technique tandem ionization mass spectrometry (TIMS) employs irradiation of gas-phase even-electron molecular ions of both polarities with >10 eV electrons. This leads to the production of radical molecular cations and anions of large biomolecules. The parent even-electron ions are produced by laser desorption, matrix-assisted laser desorption/ionization (UV and IR) or electrospray ionization and trapped in the cell of a Fourier transform mass spectrometer before irradiation with electrons. For multiply-charged polypeptide cations (up to 16+ for cytochrome c) and di-anions, TIMS produced radical [M + nH]( n + 1)+• cations and previously unreported [M − 2H]−• anions, respectively. Subsequent collisional activation of these species, in contrast to their even electron counterparts, gave only small neutral losses (mainly CO2) regardless of the ionic charge, polarity or lability. This process was rationalized through intramolecular hydrogen atom transfer in cations. Measurements of the threshold energies for electron ejection has now been extended to the protonated porphyrin C76H94N4 [ IE(MH+) = 12.8 ± 0.3 eV] and to multiply-charged polypeptide cations and anions. Serendipitously, it was found that, in the absence of electrons, [M + nH]( n + 1)+• polypeptide cations can also be formed in energetic collisions during the ion isolation process in Fourier transform mass spectrometry.
Ascorbic Acid Assessment in Human Dermis by a Microdialysis Technique Associated with Gas Chromatography-Mass Spectrometry
Authors: Leveque Nathalie , Mary Sophie , Humbert Philippe , Makki Safwat , Muret Patrice , Kantelip Jean-Pierre
Published: December 2007

Ascorbic acid (AA) plays a significant role in preventing photobiological damage in human skin which could lead to cutaneous disorders such as premature aging or skin cancer. The aim of this work was to assess AA concentrations in human dermis by a microdialysis technique associated with gas chromatography-mass spectrometry (GC-MS). Due to the non-volatility of AA, it was necessary to derivatize this acid. Three methods, one methylation and two silylations, were validated and compared to determine the most sensitive. To validate the methods, calibration curves were plotted from AA concentrations ranging from 34 to 500 nmol mL−1. The calibration curves were linear with a good correlation coefficient ( r ≥ 0.99). Repeatability and reproducibility were significant with a coefficient of variation of less than 10%. The accuracy of the techniques was meaningful as the bias was low (ranging from −5.6 to 5.0%). According to our results, silylation was the most sensitive method to assess AA. Thus, this method was performed to determine AA concentrations in microdialysates. In order to study AA in human dermis, a microdialysis method was used to sample AA and the GC-MS technique used to assess this acid in the microdialysates. Microdialysis can only partially collect AA from human dermis. An ex vivo recovery of AA was 30 ± 2% ( n = 7). The average concentration of AA in microdialysates was 250 ± 66 nmol mL−1 (Mean ± SD, n = 5). In view of the AA recovery, AA concentrations in human skin ranged from 759 to 891 nmol mL−1.
Rydberg Electron-Capture Mass Spectrometry of 1,2,3,4 Tetrachlorodibenzo-p-Dioxin
Authors: Carette M. , Zerega Y. , Perrier P. , Andre J. , March R.E.
Published: December 2007

A negative-ion creation technique by Rydberg electron capture (REC) is used to ionise 1,2,3,4 tetrachlorodibenzo- p-dioxin (1,2,3,4-TCDD). Negative ions are mass-analysed by a commercial quadrupole mass spectrometer and also by a home-made mass spectrometer using a quadrupole ion trap. From spectra of 1,2,3,4-TCDD a comparison between the REC ionisation technique and two other soft ionisation techniques, electron capture chemical ionisation (ECCI) and the electron monochromator (EM), are discussed.
Formation of Non-Specific Protein Cluster Ions in Matrix-Assisted Laser Desorption/Ionization: Abundances and Dynamical Aspects
Authors: Livadaris Vincent , Blais Jean-Claude , Tabet Jean-Claude
Published: December 2007

Intact non-covalent biological complexes resulting from interactions in solutions have been observed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF-MS). However, their analysis is hampered by the presence of non-specific, non-covalent complexes (clusters) produced under MALDI conditions. A study of the influence of laser energy and ion extraction conditions allows information to be obtained on (i) the collision regime in the plume and (ii) ion stability, through the abundances and time-of-flight ( ttof) deviations of bovine insulin clusters using a sinapinic acid matrix. In the linear mode, it is shown that (i) the neutral contribution to quasi-molecular peaks is below 10% and (ii) for related cluster species, the ttof difference between neutrals and ions is less than 10 ns. Although the abundance of cluster ions increases relatively to the abundance of the monomeric ions with laser energy, heavier cluster ions are unfavored at higher laser energy. On the other hand, the abundance of clusters is, to a first approximation, independent of the electric field in the first acceleration region (750–32,500 V cm−1) and of the extraction delay (up to 4000 ns). Gaussian-like distribution profiles are observed, whatever the acceleration field, for all cluster ion signals. This is in good agreement with the natural isotopic distribution. There is no significant difference between monomeric and cluster ion initial velocities (420 m s−1 ± 18 m s−1). Our results suggest a single origin for bovine insulin cluster ions that are observed by using a sinapinic acid matrix. The clusters should be formed promptly after the laser pulse (< 10 ns), in the selvedge of the surface. Smaller cluster ions could be formed by consecutive fragmentations of higher mass molecular clusters occurring after plume formation and before a significant ion acceleration.
Identification of Bound Alcohols in Soil Humic Acids by Gas Chromatography-Mass Spectrometry
Authors: Berthier Gersende , Dou Sen , Peakman Torren , Lichtfouse Eric
Published: December 2007

Humic acids are complex, partly macromolecular, yellow-brownish substances occurring in soils, waters and sediments. In order to shed some light on their molecular structure, crop humic acids were cleaved by alkaline hydrolysis (KOH). The products were fractionated by thin layer chromatography to give mono-alcohols which were analysed as acetate derivatives by gas chromatography coupled to mass spectrometry. Linear alcohols, sterols, stanols and plant-derived triterpenoid alcohols were identified by co-injection of pure standards and by comparison with literature data. These findings imply that alcohols could have been incorporated into the humic matrix by esterification with carboxylic acids. Furthermore, the presence of stanols as hydrogenated counterparts of sterols suggests that a process of hydrogenation is operating in soils.
Gas Chromatography-Mass Spectrometry Study of Polycyclic Aromatic Hydrocarbons in Grass and Milk from Urban and Rural Farms
Authors: Grova Nathalie , Laurent Claire , Feidt Cyril , Rychen Guido , Laurent François , Lichtfouse Eric
Published: December 2007

Polycyclic aromatic hydrocarbon (PAH) levels were studied in grass and milk sampled at two farms, one located in a non-contaminated, rural area, and another located in a urban area close to PAH sources such as highways, busy roads, fuel-powered trains and a steel plant. PAH concentration were measured by gas chromatography coupled to mass spectrometry (GC-MS) using internal deuterated standards. In grasses, unexpectedly, although the sum of PAH concentrations was only slightly higher at the urban farm (83.1 ± 16.1 ng g−1) than the rural farm (51.8 ± 10.6 ng g−1), this difference was not observed for all PAH members. This absence of a striking difference of PAH levels between urban and rural grasses suggests that atmospheric PAH sources, for example, vehicle exhausts and chimney fumes, could be rapidly diluted by winds. In milk, PAH concentrations were not significantly different at urban and rural farms.
Duty Cycle Improvement for a Quadrupole—Time-of-Flight Mass Spectrometer and its Use for Precursor Ion Scans
Authors: Chernushevich Igor V.
Published: December 2007

Normally, quadrupole–time-of-flight (QqTOF) instruments benefit from a simultaneous recording of all masses, and their sensitivity is higher than that of a triple quadrupole when a full scan is recorded. This is not the case when only a single type of ion has to be monitored, as in precursor ion scanning or multiple-reaction monitoring (MRM) mode. This is because ion losses in TOF are higher than in a quadrupole. A significant part of these losses is due to the low duty cycle of an orthogonal TOF instrument, typically 5 to 30%. Trapping ions in the collision cell and then gating them out in short bursts synchronized with TOF extraction can restore the duty cycle at the expense of mass range. The mechanism of ion trapping, gating and bunching is studied under various conditions. By varying trapping and gating parameters, different modes of operation are achievable: from a 100% duty cycle restoration for a narrow mass range to <50% duty cycle for a wider mass range. The former mode is best for a single-fragment precursor ion scan, whereas the latter is better when a full product-ion spectrum needs to be recorded, or when a multiple-fragment precursor ion scan is performed. Several examples of precursor ion scans obtained with peptides and lipids are demonstrated. Sensitivity improvements range from ×15 for the immonium fragment ion ( m/z 86) to ×5 for simultaneous recording of lipid fragments with m/z = 184 and 264.
High-Resolution Electrospray Ionization Orthogonal-Injection Time-of-Flight Mass Spectrometer
Authors: Dodonov A.F. , Kozlovski V.I. , Soulimenkov I.V. , Raznikov V.V. , Loboda A.V. , Zhen Zhou , Horwath T. , Wollnik H.
Published: December 2007

A concept of an “ideal” orthogonal-injection time-of-flight (O-TOF) mass spectrometer is proposed and a new high-resolution O-TOF mass spectrometer with an electrospray ion source and a molecule-ion reactor is described. The instrument design was optimized for high resolution and sensitivity using the concept of an ideal O-TOF mass spectrometer. A mass resolving power of about 20,000 (full width at half maximum) and a mass measurement accuracy in the 10 ppm range is demonstrated.
Ideal Space Focusing in a Time-of-Flight Mass Spectrometer: An Optimization Using an Analytical Approach
Authors: Doroshenko Vladimir M.
Published: December 2007

An exact, analytical solution for an electric field in a nonlinear acceleration region of an ion source for the cases of linear and reflectron time-of-flight (TOF) mass spectrometers has been found to achieve universal temporal focusing of ions having an initial space distribution. The general solutions are valid for an arbitrary electric field distribution in the drift region (from the ion source to an ion detector) of a linear TOF mass spectrometer, and in the upstream (from the ion source to the reflectron) and downstream (from the reflectron to an ion detector) regions of a reflectron TOF instrument. This may include, for example, electrostatic lenses commonly used after an ion source for angular focusing of ions onto the detector to increase the instrument sensitivity and additional acceleration of ions before their detection. Using analytical expressions obtained for an arbitrary case, convenient working formulae are derived for the widely used single- and dual-stage ion extraction schemes in the cases of linear and reflectron TOF mass spectrometers. The formulae are used in optimizing the TOF mass spectrometer design by decreasing the curvature of the nonlinear acceleration potential in the ion source. The relationship has been shown between the conditions for an ideal space focusing using an optimized curved extraction field and a finite-order space-focusing using a linear extraction field in an ion source. The results obtained are especially useful for designing miniature TOF mass spectrometers or instruments with large volume ion sources.
A Novel Non-Linear Ion Mirror with Only Three Elements
Authors: Zhang Jun , Enke Christie G.
Published: December 2007

A novel tubular ion mirror has been designed for reflectron time-of-flight mass spectrometry (TOF-MS). This design consists of only three cylindrical elements. With this mirror, an electric field is achieved that is non-linear along the mirror axis and has improved off-axis homogeneity compared with conventional simple geometry ion mirrors. The practical operation of this mirror is simpler than that of conventional diaphragm ion mirrors. Design parameters, including the relative lengths and voltages of the three elements, can be determined empirically. Once the mirror depth dimensions have been implemented, the voltages of the middle and rear elements are the only adjustable parameters. The electric field achieved by the mirror deviates only slightly from a linear mirror with constant field strength. The second-order deviation curve reveals two regions of curvature; all ions are turned around in the second curvature region. A plot of arrival time vs ion kinetic energy has a flattened “S” shape. The aspects of this shape are affected by the voltages of the middle and rear elements. SIMION 7 simulation demonstrates that this new non-linear ion mirror can perform second-order kinetic energy correction for large kinetic energy variation (33%) and substantial beam dimensions. Both the ion kinetic energy variation and the mirror element voltages affect the mass resolution obtained with the mirror. Ion trajectory simulations with a 10 mm diameter beam from a standard, two-field source predict that baseline resolution can be 16,000, 7600 and 1200 for 15%, 26% and 33% kinetic energy variations, respectively.
A Quadratic-Field Reflectron Time-of-Flight Mass Spectrometer Incorporating Intermediate Temporal Focusing
Authors: Colburn Alex W. , Giannakopulos A.E. , Derrick Peter J. , von Raumer Markus
Published: December 2007

A time-of-flight mass spectrometer, using a two-electrode cone-plus-hyperboloid geometry to produce a quadratic reflecting field, has been designed, constructed and tested. The included angle of the cone was 90°. Matrix-assisted laser desorption/ionisation and direct laser desorption/ionisation were the methods used to produce ions. Physical constraints imposed by the geometry of the ion mirror were overcome by the use of ion-bunching to form an intermediate temporal focus. Experimental and ion-optical simulation results are presented, showing the large energy-bandwidth of the quadratic-field reflectron and the effectiveness of ion-bunching as a method of producing a temporal focus at the entrance to the ion mirror.
Scatter Search for the Point-Matching Problem in 3D Image Registration
Authors: Cordón Oscar , Damas Sergio , Santamaría Jose , Martí Rafael
Published: December 2007

Scatter search is a population-based method that has recently been shown to yield promising outcomes for solving combinatorial and nonlinear optimization problems. Based on formulations originally proposed in the 1960s for combining decision rules and problem constraints, such as the surrogate constraint method, scatter search uses strategies for combining solution vectors that have proved effective in a variety of problem settings.

We present a scatter-search implementation designed to find high-quality solutions for the 3D image-registration problem, which has many practical applications. This problem arises in computer vision applications when finding a correspondence or transformation between two computer images obtained under different conditions. Our implementation goes beyond a simple exercise on applying scatter search, by incorporating innovative mechanisms to combine and improve solutions and to create a balance between intensification and diversification in the reference set. Furthermore, heuristic information taken from a preprocessing of the images is incorporated into the algorithm to improve its performance. Our computational experimentation tackling two different medical registration applications establishes the effectiveness of scatter search in relation to different approaches usually applied to solving the problem. We have considered both simulated magnetic resonance images and real-world computerized tomography images as data sets. To measure the robustness of our proposal, the image data sets are intentionally selected for addressing registration environments with the presence of noise, anatomical lesions, and occlusions between images.
Intrusion-Detection Policies for IT Security Breaches
Authors: Ogut Hulisi , Cavusoglu Huseyin , Raghunathan Srinivasan
Published: December 2007

Intrusion-detection systems (IDSs) form an important component of IT security architectures, but the low proportion of hackers in the user population severely limits the usefulness of IDSs. Thus, even when the IDS is good, an intrusion signal may not imply that the user is more likely to be a hacker than a normal user. Ignoring the low base rate for the proportion of hackers results in acting on every intrusion signal, which is costly because of the high rate of false alarms. This problem is known as the base-rate fallacy in IDSs. On the other hand, ignoring intrusion signals renders IDSs useless. We propose and analyze waiting-time policies, which specify a response to signals from IDSs. We formulate the problem as a stochastic dynamic programming model and derive the optimal waiting time before acting upon an intrusion signal. Because the optimal policy is difficult to implement in many situations, we also derive and theoretically analyze a myopic policy. Our simulations suggest that the behavior of the myopic policy is qualitatively similar to that of the optimal policy. Further, the myopic policy performs better than other policies often used in practice, such as the Bayes policy and m-strike policies. The myopic policy can be implemented easily in a decision support system that supplements an IDS to mitigate the base-rate fallacy and to improve the value of the IDS.
Risk in Revenue Management and Dynamic Pricing
Authors: Levin Yuri , McGill Jeff , Nediak Mikhail
Published: December 2007

We present a new model for optimal dynamic pricing of perishable services or products that incorporates a simple risk measure permitting control of the probability that total revenues fall below a minimum acceptable level. The formulation assumes that sales must occur within a finite time period, that there is a finite—possibly large—set of available prices, and that demand follows a price-dependent, nonhomogeneous Poisson process. This model is particularly appropriate for applications in which attainment of a revenue target is an important consideration for managers; for example, in event management, in seasonal clearance of high-value items, or for business subunits operating under performance targets. We formulate the model as a continuous-time optimal control problem, obtain optimality conditions, explore structural properties of the solution, and report numerical results on problems of realistic size.
Arrival Rate Approximation by Nonnegative Cubic Splines
Authors: Alizadeh Farid , Eckstein Jonathan , Noyan Nilay , Rudolf Gábor
Published: December 2007

We describe an optimization method to approximate the arrival-rate function of a nonhomogeneous Poisson process based on observed arrival data. We estimate the function by cubic splines, using an optimization model based on the maximum-likelihood principle. A critical feature of the model is that the splines are constrained to be nonnegative everywhere. We enforce these constraints by using a characterization of nonnegative polynomials by positive semidefinite matrices. We also describe versions of our model that allow for periodic arrival-rate functions and input data of limited time precision. We formulate the estimation problem as a convex nonlinear program, and solve it with standard nonlinear optimization packages. We present numerical results using both an actual record of e-mail arrivals over a period of 60 weeks, and artificially generated data sets. We also present a cross-validation procedure for determining an appropriate number of spline knots to model a set of arrival observations.
Optimal recovery in problems of solving linear integral equations with a priori information
Authors: Bayev A. V. , Yagola A. G.
Published: December 2007

The article is devoted to a Lagrange principle application to a problem of optimal recovery of a linear functional value on a solution of a linear integral equation. Problems of solving Fredholm integral equations of the first and second kind and the Abel integral equation are considered. A priori information on a solution is included in a statement of problems. The algorithms of optimal recovery of linear functionals on solutions are described.
Unique continuation for hyperbolic equations with memory
Authors: Bukhgeim A. L. , Dyatlov G. V. , Uhlmann G.
Published: December 2007

We prove the unique continuation property for the hyperbolic integro-differential equation
Research Participants' Perceptions of the Certificate of Confidentiality's Assurances and Limitations
Authors: Catania Joseph A. , Wolf Leslie E. , Wertleib Stacey , Lo Bernard , Henne Jeff
Published: December 2007

The certificate of confidentiality (COC) provides additional protections to personal and sensitive research data. COC guarantees are not absolute and investigators are obligated to inform potential participants of COC limitations. The present study utilized qualitative and partnership methodology to examine participants' (N = 24) perceptions of COC assurances and limitations in the context of a hypothetical study on depression. Although some participants were comforted by COC assurances, a majority of participants had confidentiality/privacy concerns specifically with COC passages concerning federal audits and legal reporting requirements. As one respondent noted, “Why is it that you guys don't have to turn the records over to the court unless I say so … but you have to give them over to the government?… I don't know about what is goin‘ on.” Our findings underscore the need for larger quantitative investigations to examine the negative and positive impact of COCs on research participation and response bias.
Fetal oncology
Authors: Jakobovits Ákos
Published: December 2007

A szerző áttekinti a magzatokban előforduló jó- és rosszindulatú daganatokat. A gyermek- és felnőttkori daganatok szinte minden alakja előfordul méhen belül a magzatokban, illetve világrajövetel után az újszülöttekben. A diagnózis létfontosságú eszköze a szonográfia és a mágneses rezonanciás vizsgálati módszer. Ez a két eljárás nagy előrelépés a kórismézés terén. A kezelések még kísérleti fázisban vannak, és csak néhány központi intézetben végeznek ilyen beavatkozásokat. A választás a műtéti beavatkozás kockázat-haszon arányától függ.
Ruptured cirrhotic nodulus treated with collagen patch
Authors: Papp Zoltán , Czakó Tamás
Published: December 2007

A szerzők közleményükben egy 53 éves, krónikus alkoholista betegük esetét ismertetik, akit akut has diagnózisával, rossz általános állapotban vettek fel. A képalkotó eljárások az ascites mellett vért is jeleztek a hasüregben, ezért a beteg keringésének rendezése után urgens műtétet végeztek, melynek során a máj mindkét lebenyére terjedő durva göbös cirrhosist találtak. A jobb májlebeny rekeszi felszínéhez közel egy női ökölnyi nagyságú cirrhoticus göb spontán rupturáját észlelték, spriccelő artériás vérzéssel, melyet Tacho-Comb-szövetragasztóval láttak el. Betegük gyógyult.
Detection of Toxoplasma gondii-like oocysts in cat feces and estimates of the environmental oocyst burden
Authors: Dabritz Haydee A. , Miller Melissa A. , Atwill E. Robert , Gardner Ian A. , Leutenegger Christian M. , Melli Ann C. , Conrad Patricia A.
Published: December 2007

Objective—To estimate the analytic sensitivity of microscopic detection of Toxoplasma gondii oocysts and the environmental loading of T gondii oocysts on the basis of prevalence of shedding by owned and unowned cats.

Design—Cross-sectional survey.

Sample Population—326 fecal samples from cats.

Procedures—Fecal samples were collected from cat shelters, veterinary clinics, cat-owning households, and outdoor locations and tested via ZnSO4 fecal flotation.

Results—Only 3 (0.9%) samples of feces from 326 cats in the Morro Bay area of California contained T gondii–like oocysts. On the basis of the estimated tonnage of cat feces deposited outdoors in this area, the annual burden in the environment was estimated to be 94 to 4,671 oocysts/m2 (9 to 434 oocysts/ft2).

Conclusions and Clinical Relevance—Despite the low prevalence and short duration of T gondii oocyst shedding by cats detected in the present and former surveys, the sheer numbers of oocysts shed by cats during initial infection could lead to substantial environmental contamination. Veterinarians may wish to make cat owners aware of the potential threats to human and wildlife health posed by cats permitted to defecate outdoors.
Risk factors for excessive tibial plateau angle in large-breed dogs with cranial cruciate ligament disease
Authors: Duerr Felix M. , Duncan Colleen G. , Savicky Roman S. , Park Richard D. , Egger Erick L. , Palmer Ross H.
Published: December 2007

Objective—To identify risk factors for development of excessive tibial plateau angle (TPA) in large-breed dogs with cranial cruciate ligament disease (CCLD).

Design—Case-control study.

Animals—58 dogs with excessive TPAs (ie, TPA ≥ 35°; case dogs) and 58 dogs with normal TPAs (ie, TPA ≤ 30°; control dogs).

Procedures—Medical records and radiographs were reviewed and owners were interviewed to identify potential risk factors for excessive TPA.

Results—Case dogs were 3 times (95% confidence interval, 1.2 to 8.0) as likely to have been neutered before 6 months of age as were control dogs. Case dogs with TPA ≥ 35° in both limbs were 13.6 times (95% confidence interval, 2.72 to 68.1) as likely to have been neutered before 6 months of age as were control dogs with TPA ≤ 30° in both limbs. Case dogs were significantly younger at the onset of hind limb lameness than were control dogs.

Conclusions and Clinical Relevance—Results suggested that early neutering was a significant risk factor for development of excessive TPA in large-breed dogs with CCLD. Further research into the effects of early neutering on TPA and the pathophysiology of CCLD is warranted.
A field study of the effects of a monovalent Leptospira borgpetersenii serovar Hardjo strain hardjobovis vaccine administered with oxytetracycline on reproductive performance in beef cattle
Authors: Kasimanickam Ramanathan , Whittier William D. , Collins Jonathan C. , Currin John F. , Inman Bom , Hall John B. , Pelzer Kevin D.
Published: December 2007

Objective—To determine whether vaccination with a monovalent Leptospira borgpetersenii serovar Hardjo strain hardjobovis vaccine coupled with parenteral long-acting oxytetracycline treatment would improve the reproductive performance of beef cows.

Design—Randomized controlled field trial.

Animals—1,446 Angus-cross beef cows in 8 locations.

Procedures—Cows were given 2 doses, 4 weeks apart, of vaccine (treatment; n = 741) or placebo (control; 705). Cows in the treatment group were also given a single dose of a longacting oxytetracycline formulation (20 mg/kg [9.1 mg/lb], SC) at the time of booster vaccination. Estrus synchronization was performed, followed by fixed-time artificial insemination; bulls were introduced 14 days after insemination. Serum and urine samples were obtained on a random subset of cows (n = 194) for detection of serologic titers and leptospiruria, and locations were categorized as positive or negative for leptospirosis on the basis of detection of leptospiruric cows.

Results—No differences in pregnancy and calving rates between treatment and control groups were detected. Pregnancy rate following artificial insemination was lower among cows in locations positive for leptospirosis than among cows in locations negative for leptospirosis; however, overall pregnancy rate, calving rate following artificial insemination, and overall calving rate did not differ between groups when cows were grouped on the basis of location leptospirosis status.

Conclusions and Clinical Relevance—Results suggested that under the conditions of the present study, administration of a monovalent Leptospira vaccine in conjunction with systemic administration of oxytetracycline did not significantly improve reproductive performance of beef cows.
An outbreak of dictyocaulosis in lactating cows on a dairy farm
Authors: Wapenaar Wendela , Barkema Herman W. , Eysker Maarten , O'Handley Ryan M.
Published: December 2007

Case Description—The owner of a herd of 74 Holstein-Friesian cattle reported decreased milk production, weight loss, and coughing among lactating cows. Owner-initiated antimicrobial treatment was unsuccessful; 1 lactating cow died, and 50% of the lactating cows had clinical signs of respiratory distress, such as tachypnea and coughing.

Clinical Findings—On the basis of history, physical examination findings, and fecal examination results, affected animals were determined to have Dictyocaulus viviparus (lungworm) infestation. The disease history suggested that the herd contained cows with subclinical patent lungworm infestations; after introduction of susceptible heifers, the pastures had become heavily infested with D viviparus and clinical problems subsequently developed in both newly introduced and resident cows.

Treatment and Outcome—Affected and unaffected heifers and adult cows were treated with a pour-on formulation of eprinomectin (0.5 mg/kg [0.23 mg/lb]). One animal died, but 2 weeks after treatment, clinical signs among affected cattle were markedly improved. Ten weeks after treatment, milk production improved from 23 kg/cow/d (51 lb/cow/d) to 28 kg/cow/d (62 lb/cow/d).

Clinical Relevance—The outbreak provides additional evidence that dictyocaulosis is becoming more common among adult dairy cattle, rather than almost exclusively affecting young stock. This may be attributable to anthelmintic use and management practices on dairy farms. Combined with anecdotal reports of an increase in the incidence of dictyocaulosis among adult cattle in North America, D viviparus infestation should be included as a differential diagnosis for decreased milk production, weight loss, and coughing among adult dairy cattle.
Gliadel Wafers in the Treatment of Malignant Glioma: A Systematic Review
Authors: Perry James , Chambers A. , Spithoff K. , Laperriere N. ,   on behalf of the Neuro-Oncology Disease Site Group§ of Cancer Care Ontario’s Program in Evidence-Based Care
Published: December 2007

Question: What is the safety and efficacy of interstitial chemotherapy with carmustine-loaded polymers (Gliadel wafers: MGI Pharma, Bloomington, MN, U.S.A.) in the treatment of newly diagnosed or recurrent malignant glioma (that is, glioblastoma multiforme, anaplastic astrocytoma, anaplastic oligoastrocytoma, and anaplastic oligodendroglioma)? Perspectives: Malignant glioma is the most common type of primary brain tumour in adults. In general, efficacy of systemic therapy in this patient population has been disappointing, and novel treatment approaches are needed. Because several randomized controlled trials (rcts) investigating the safety and efficacy of Gliadel are available, the Neuro-oncology Disease Site Group of Cancer Care Ontario’s Program in Evidence-Based Care decided that a systematic review of the evidence was necessary. Outcomes: The outcomes of interest for this review were overall survival, adverse events, and quality of life. Methodology: Systematic searches of the medline, embase, and Cochrane Library databases were conducted for relevant evidence. Fully-published reports of rcts comparing treatment with Gliadel wafers to placebo or alternative treatment were selected for inclusion. Prospective cohort studies were also included. Results: Two rcts that compared Gliadel to placebo in patients with newly diagnosed malignant glioma were obtained. Both rcts reported a significant survival benefit for patients who received Gliadel as compared with patients in the control group. One rct and one prospective cohort study were obtained that examined the role of Gliadel in patients with recurrent malignant glioma. The rct demonstrated a significant survival benefit for Gliadel only after adjustment for prognostic factors, and the prospective cohort study reported no survival benefit for Gliadel as compared with a historical control group. All three rcts reported similar rates of adverse events in the treatment and control groups. The most frequently reported adverse events were convulsions, confusion, brain edema, infection, hemiparesis, aphasia, and visual field defects. Conclusions: Gliadel is an option for selected patients with newly diagnosed malignant glioma where a near gross total resection is possible. No evidence is available comparing Gliadel with systemic therapy, and a decision to combine Gliadel with systemic therapy should be made for patients individually. The patient population that would benefit from Gliadel (age, histology, and performance status) is unclear; further investigation is needed. Gliadel is also an option for patients with surgically resectable recurrent malignant glioma.
Anatomy for biomedical engineers
Authors: Carmichael Stephen W. , Robb Richard A.
Published: December 2007

There is a perceived need for anatomy instruction for graduate students enrolled in a biomedical engineering program. This appeared especially important for students interested in and using medical images. These students typically did not have a strong background in biology. The authors arranged for students to dissect regions of the body that were of particular interest to them. Following completion of all the dissections, the students presented what they had learned to the entire class in the anatomy laboratory. This course has fulfilled an important need for our students. Anat Sci Ed 1:90–91, 2008. © 2007 American Association of Anatomists.
CAVEman: Standardized anatomical context for biomedical data mapping
Authors: Turinsky Andrei L. , Fanea Elena , Trinh Quang , Wat Stephen , Hallgrímsson Benedikt , Dong Xiaoli , Shu Xueling , Stromer Julie N. , Hill Jonathan W. , Edwards Carol , Grosenick Brenda , Yajima Masumi , Sensen Christoph W.
Published: December 2007

The authors have created a software system called the CAVEman, for the visual integration and exploration of heterogeneous anatomical and biomedical data. The CAVEman can be applied for both education and research tasks. The main component of the system is a three‐dimensional digital atlas of the adult male human anatomy, structured according to the nomenclature ofTerminologia Anatomica. The underlying data‐indexing mechanism uses standard ontologies to map a range of biomedical data types onto the atlas. The CAVEman system is now used to visualize genetic processes in the context of the human anatomy and to facilitate visual exploration of the data. Through the use of Java™ software, the atlas‐based system is portable to virtually any computer environment, including personal computers and workstations. Existing Java tools for biomedical data analysis have been incorporated into the system. The affordability of virtual‐reality installations has increased dramatically over the last several years. This creates new opportunities for educational scenarios that model important processes in a patient's body, including gene expression patterns, metabolic activity, the effects of interventions such as drug treatments, and eventually surgical simulations. Anat Sci Ed 1:10–18, 2008. © 2007 American Association of Anatomists.
Coupled physical and digital cadaver dissection followed by a visual test protocol provides insights into the nature of anatomical knowledge and its evaluation
Authors: Hisley Kenneth C. , Anderson Larry D. , Smith Stacy E. , Kavic Stephen M. , Tracy J. Kathleen
Published: December 2007

This research effort compared and contrasted two conceptually different methods for the exploration of human anatomy in the first‐year dissection laboratory by accomplished students: “physical” dissection using an embalmed cadaver and “digital” dissection using three‐dimensional volume modeling of whole‐body CT and MRI image sets acquired using the same cadaver. The goal was to understand the relative contributions each method makes toward student acquisition of intuitive sense of practical anatomical knowledge gained during “hands‐on” structural exploration tasks. The main instruments for measuring anatomical knowledge under this conceptual model were questions generated using a classification system designed to assess both visual presentation manner and the corresponding response information required. Students were randomly divided into groups based on exploration method (physical or digital dissection) and then anatomical region. The physical dissectors proceeded with their direct methods, whereas the digital dissectors generated and manipulated indirect 3D digital models. After 6 weeks, corresponding student anatomical assignment teams compared their results using photography and animated digital visualizations. Finally, to see whether each method provided unique advantages, a visual test protocol of new visualizations based on the classification schema was administered. Results indicated that all students, regardless of gender, dissection method, and anatomical region dissected performed significantly better on questions presented as rotating models requiring spatial ordering or viewpoint determination responses in contrast to requests for specific lexical feature identifications. Additional results provided evidence of trends showing significant differences in gender and dissection method scores. These trends will be explored with further trials with larger populations. Anat Sci Ed 1:27–40, 2008. © 2007 American Association of Anatomists.
Evaluation of small‐group teaching in human gross anatomy in a Caribbean medical school
Authors: Chan Lap Ki , Ganguly Pallab K.
Published: December 2007

Although there are a number of medical schools in the Caribbean islands, very few reports have come out so far in the literature regarding the efficacy of small‐group teaching in them. The introduction of small‐group teaching in the gross anatomy laboratory one and a half years ago at St. Matthew's University (SMU) on Grand Cayman appears to have had a significant positive impact on the academic achievement of students in anatomy. This study surveyed the responses of the students to the small‐group learning method in gross anatomy at SMU using a structured questionnaire. The results show that our students prefer this small‐group learning method over a completely self‐directed method in the gross anatomy lab because the study materials were carefully chosen and the study objectives were demonstrated by the resource person. However, teacher‐centered teaching was deliberately avoided by fostering problem‐solving skills in the anatomy lab sessions. Another aim of the small‐group teaching at SMU was to develop the interpersonal and communication skills of the students, which are important in their later education and career. Anat Sci Ed 1:19–22, 2008. © 2007 American Association of Anatomists.
Question‐driven segmentation of lecture speech text: Towards intelligent e‐learning systems
Authors: Lin Ming , Zhang Zhu
Published: December 2007

Recently, lecture videos have been widely used in e‐learning systems. Envisioning intelligent e‐learning systems, this article addresses the challenge of information seeking in lecture videos by retrieving relevant video segments based on user queries, throughdynamic segmentationoflecture speech text. In the proposed approach, shallow parsing such as part of‐speech tagging and noun phrase chunking are used to parse both questions and Automated Speech Recognition (ASR) transcripts. A sliding‐window algorithm is proposed to identify the start and ending boundaries of returned segments. Phonetic and partial matching is utilized to correct the errors from automated speech recognition and noun phrase chunking. Furthermore, extra knowledge such as lecture slides is used to facilitate the ASR transcript error correction. The approach also makes use of proximity to approximate the deep parsing and structure match between question and sentences in ASR transcripts. The experimental results showed that both phonetic and partial matching improved the segmentation performance, slides‐based ASR transcript correction improves information coverage, and proximity is also effective in improving the overall performance.
Information retrieval on Turkish texts
Authors: Can Fazli , Kocberber Seyit , Balcik Erman , Kaynak Cihan , Ocalan H. Cagdas , Vursavas Onur M.
Published: December 2007

In this study, we investigate information retrieval (IR) on Turkish texts using a large‐scale test collection that contains 408,305 documents and 72 ad hoc queries. We examine the effects of several stemming options and query‐document matching functions on retrieval performance. We show that a simple word truncation approach, a word truncation approach that uses language‐dependent corpus statistics, and an elaborate lemmatizer‐based stemmer provide similar retrieval effectiveness in Turkish IR. We investigate the effects of a range of search conditions on the retrieval performance; these include scalability issues, query and document length effects, and the use of stopword list in indexing.
Bibliometric statistical properties of the 100 largest European research universities: Prevalent scaling rules in the science system
Authors: Raan Anthony F.J. van
Published: December 2007

The statistical properties of bibliometric indicators related to research performance, field citation density, and journal impact were studied for the 100 largest European research universities. A size‐dependent cumulative advantage was found for the impact of universities in terms of total number of citations. In the author's previous work, a similar scaling rule was found at the level of research groups. Therefore, this scaling rule is conjectured to be a prevalent property of the science system. The lower performance universities have a larger size‐dependent cumulative advantage for receiving citations than top performance universities. For the lower performance universities, the fraction of noncited publications decreases considerably with size. Generally, the higher the average journal impact of the publications of a university, the lower the number of noncited publications. The average research performance was found not to dilute with size. Evidently, large universities, particularly top performance universities are characterized by being “big and beautiful.” They succeed in keeping a high performance over a broad range of activities. This most probably is an indication of their overall attractive scientific and intellectual power. It was also found that particularly for the lower performance universities, the field citation density provides a strong cumulative advantage in citations per publication. The relation between number of citations and field citation density found in this study can be considered as a second basic scaling rule of the science system. Top performance universities publish in journals with significantly higher journal impact as compared to the lower performance universities. A significant decrease of the fraction of self‐citations with increasing research performance, average field citation density, and average journal impact was found.
Inferences on the Common Mean of Several Log‐Normal Populations: The Generalized Variable Approach
Authors: Tian Lili , Wu Jianrong
Published: December 2007

This paper proposes a novel approach for the confidence interval estimation and hypothesis testing of the common mean of several log‐normal populations using the concept of generalized variable. Simulation studies demonstrate that the proposed approach can provide confidence intervals with satisfying coverage probabilities and can perform hypothesis testing with satisfying type‐I error control even at small sample sizes. Overall, it is superior to the large sample approach. The proposed method is illustrated using two examples. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pile foundation design using Microsoft Excel
Authors: Canakci Hanifi
Published: December 2007

This article presents a program called Pile‐D developed for the teaching of pile foundation design to undergraduate level geotechnical engineering students. The program performs drained and undrained analysis for frictional resistance of the pile in clay, and uses critical depth approach for the analysis of the pile in sand. © 2007 Wiley Periodicals, Inc. Comput Appl Eng Educ 15: 355–366, 2007; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20206
Adjunct faculty and the continuing quest for quality
Authors: Green Donald W.
Published: December 2007

This chapter addresses the use of adjunct faculty in community colleges. It examines issues of finding, hiring, orienting, evaluating, and developing adjuncts and stresses critical areas of ensuring quality and maintaining institutional standards.
Part‐time faculty in California: Successes, challenges, and future issues
Authors: Yoshioka Robert B.
Published: December 2007

This chapter highlights some issues that are being addressed, discussed, and analyzed by part‐time faculty in the California Community College system.