bluuebunny/crossref_metadata_2025 huggingface dataset:
Ontogeny of joint mechanics in squirrel monkeys (Saimiri boliviensis): functional implications for mammalian limb growth and locomotor development
Authors: Young Jesse W.
Published: May 2009

Juvenile animals must often compete against adults for common resources,keep pace during group travel and evade common predators, despite reduced body size and an immature musculoskeletal system. Previous morphometric studies of a diverse array of mammals, including jack rabbits, cats and capuchin monkeys,have identified growth-related changes in anatomy, such as negative allometry of limb muscle mechanical advantage, which should theoretically permit young mammals to overcome such ontogenetic limits on performance. However, it is important to evaluate the potential impact of such `compensatory' growth trajectories within the context of developmental changes in locomotor behavior. I used standard kinematic and kinetic techniques to investigate the ontogenetic scaling of joint postures, substrate reaction forces, joint load arm lengths and external joint moments in an ontogenetic sample of squirrel monkeys (Saimiri boliviensis). Results indicated that young squirrel monkeys were frequently able to limit forelimb and hind limb joint loading via a combination of changes in limb posture and limb force distribution,potentially compensating for limited muscularity at younger ages. These results complement previous morphometric studies and suggest that immature mammals may utilize a combination of behavioral and anatomical mechanisms to mitigate ontogenetic limits on locomotor performance. However, ontogenetic changes in joint posture, not limb length per se, explained most of the variation in load arm lengths and joint loading in growing squirrel monkeys, indicating the importance of incorporating both anatomical and performance measures when studying the ontogeny of limb joint mechanics.
Pulsed jet dynamics of squid hatchlings at intermediate Reynolds numbers
Authors: Bartol Ian K. , Krueger Paul S. , Stewart William J. , Thompson Joseph T.
Published: May 2009

Squid paralarvae (hatchlings) rely predominantly on a pulsed jet for locomotion, distinguishing them from the majority of aquatic locomotors at low/intermediate Reynolds numbers (Re), which employ oscillatory/undulatory modes of propulsion. Although squid paralarvae may delineate the lower size limit of biological jet propulsion, surprisingly little is known about the hydrodynamics and propulsive efficiency of paralarval jetting within the intermediate Re realm. To better understand paralarval jet dynamics, we used digital particle image velocimetry(DPIV) and high-speed video to measure bulk vortex properties (e.g. circulation, impulse, kinetic energy) and other jet features [e.g. average and peak jet velocity along the jet centerline (Uj and Ujmax, respectively), jet angle, jet length based on the vorticity and velocity extents (Lω and LV, respectively), jet diameter based on the distance between vorticity peaks (Dω), maximum funnel diameter (DF), average and maximum swimming speed(U and Umax, respectively)] in free-swimming Doryteuthis pealeii paralarvae (1.8 mm dorsal mantle length)(Resquid=25–90). Squid paralarvae spent the majority of their time station holding in the water column, relying predominantly on a frequent, high-volume, vertically directed jet. During station holding,paralarvae produced a range of jet structures from spherical vortex rings(Lω/Dω=2.1, LV/DF=13.6) to more elongated vortex ring structures with no distinguishable pinch-off(Lω/Dω=4.6, LV/DF=36.0). To swim faster,paralarvae increased pulse duration and Lω/Dω, leading to higher impulse but kept jet velocity relatively constant. Paralarvae produced jets with low slip, i.e. ratio of jet velocity to swimming velocity(Uj/U or Ujmax/Umax), and exhibited propulsive efficiency [ηpd=74.9±8.83% (±s.d.) for deconvolved data] comparable with oscillatory/undulatory swimmers. As slip decreased with speed, propulsive efficiency increased. The detection of high propulsive efficiency in paralarvae is significant because it contradicts many studies that predict low propulsive efficiency at intermediate Re for inertial forms of locomotion.
Cloning and functional expression of the first eukaryotic Na+–tryptophan symporter, AgNAT6
Authors: Meleshkevitch Ella A. , Robinson Marvin , Popova Lyudmila B. , Miller Melissa M. , Harvey William R. , Boudko Dmitri Y.
Published: May 2009

The nutrient amino acid transporter (NAT) subfamily of the neurotransmitter sodium symporter family (NSS, also known as the solute carrier family 6, SLC6)represents transport mechanisms with putative synergistic roles in the absorption of essential and conditionally essential neutral amino acids. It includes a large paralogous expansion of insect-specific genes, with seven genes from the genome of the malaria mosquito, Anopheles gambiae. One of the An. gambiae NATs, AgNAT8, was cloned, functionally expressed and characterized in X. laevis oocytes as a cation-coupled symporter of aromatic amino acids, preferably l-phenylalanine, l-tyrosine and l-DOPA. To explore an evolutionary trend of NAT-SLC6 phenotypes, we have cloned and characterized AgNAT6, which represents a counterpart of AgNAT8 descending from a recent gene duplication(53.1% pairwise sequence identity). In contrast to AgNAT8, which preferably mediates the absorption of phenol-branched substrates, AgNAT6 mediates the absorption of indole-branched substrates with highest apparent affinity to tryptophan (K0.5Trp=1.3 μmol l–1vs K0.5Phe=430 μmol l–1) and [2 or 1 Na+ or K+]:[aromatic substrate] stoichiometry. AgNAT6 is highly transcribed in absorptive and secretory regions of the alimentary canal and specific neuronal structures,including the neuropile of ventral ganglia and sensory afferents. The alignment of AgNATs and LeuTAa, a bacterial NAT with a resolved 3D structure, reveals three amino acid differences in the substrate-binding pocket that may be responsible for the indole- vs phenol-branch selectivity of AgNAT6 vs AgNAT8. The identification of transporters with a narrow selectivity for essential amino acids suggests that basal expansions in the SLC6 family involved duplication and retention of NATs,improving the absorption and distribution of under-represented essential amino acids and related metabolites. The identified physiological and expression profiles suggest unique roles of AgNAT6 in the active absorption of indole-branched substrates that are used in the synthesis of the neurotransmitter serotonin as well as the key circadian hormone and potent free-radical scavenger melatonin.
Desert ants do not rely on sky compass information for the perception of inclined path segments
Authors: Heß Doreen , Koch Julja , Ronacher Bernhard
Published: May 2009

On their foraging excursions, desert ants (Cataglyphis fortis)navigate by means of path integration, exhibiting high precision even in undulating terrain. To avoid errors in their home vector the ants must measure the slopes of ascents and descents in their itinerary. This information is necessary to convert the distances actually walked on the slopes into the ground distance, which is the crucial parameter for vector navigation. However, it is as yet unknown how Cataglyphis perceives the slopes of inclines. We asked whether the ants gauge slopes by means of the changes in the sky's polarization pattern or the sun's position imposed by the unusual head posture when walking on inclines. During training on a ramp, we manipulated the sky compass cues available for the ants. If both sky compass cues, polarization pattern and sun position, were excluded during ramp training, the ants behaved in subsequent tests as if they had never encountered a slope. However, the presence of either of the two compass cues was sufficient for the ants to memorize the sloped path segment. In a third experiment, the supposed polarization cue was excluded by covering the training and test channels with a linear polarization filter. In these tests the ants clearly showed that they had perceived and memorized an ascent also without a change in the polarization pattern. Hence, changes in polarization perception can be ruled out as the crucial cue for gauging slopes, and we conclude that slopes are monitored by a, still unknown, proprioceptive mechanism.
Increased locomotor activity and metabolism ofAedes aegyptiinfected with a life-shortening strain ofWolbachia pipientis
Authors: Evans Oliver , Caragata Eric P. , McMeniman Conor J. , Woolfit Megan , Green David C. , Williams Craig R. , Franklin Craig E. , O'Neill Scott L. , McGraw Elizabeth A.
Published: May 2009

A virulent strain of the obligate intracellular bacterium Wolbachia pipientis that shortens insect lifespan has recently been transinfected into the primary mosquito vector of dengue virus, Aedes aegypti L. The microbe's ability to shorten lifespan and spread through host populations under the action of cytoplasmic incompatibility means it has the potential to be used as a biocontrol agent to reduce dengue virus transmission. Wolbachia is present in many host tissues and may have local effects on diverse biological processes. In other insects, Wolbachiainfections have been shown to alter locomotor activity and response time to food cues. In mosquitoes, locomotor performance relates to the location of mates, human hosts, resting sites and oviposition sites. We have therefore examined the effect of the virulent, life-shortening Wolbachia strain wMelPop on the locomotion of Ae. aegypti as they age and as the pathogenicity of the infection increases. In parallel experiments we also examined CO2 production as a proxy for metabolic rate, to investigate a potential mechanistic explanation for any changes in locomotion. Contrary to expectation, we found that the infection increased activity and metabolic rate and that these effects were relatively consistent over the insect's lifespan. The results do not fit a standard model of bacterial pathogenesis in insects, and instead may reveal additional physiological changes induced by infection, such as either increased hunger or defects in the nervous system.
Testing and modelling of soft connective tissues of joints: A review
Authors: Masouros S D , Parker K H , Hill A M , Amis A A , Bull A M J
Published: May 2009

There is wealth of data from experimental and numerical methods of analysing and modelling soft connective tissues of joints. In recent years, the advances in computational and technological capabilities allowed for several aspects of the function and mechanical behaviour of soft connective tissues of joints to be explored. However, the nature of soft tissue poses a great challenge in characterizing its material behaviour in a repeatable and physiologically or clinically relevant manner. This review article attempts to present, critique, and suggest experimental and numerical methods that are associated with the function and mechanical response of soft connective tissues of joints.
A small displacement torsor model for tolerance analysis in a workpiece-fixture assembly
Authors: Asante J N
Published: May 2009

Workpiece geometric error, locator geometric error, and clamping error are factors that influence workpiece setup in workpiece fixturing. These errors accumulate and propagate during fixturing. They may be the reason for a machined feature being out of tolerance after machining. This paper presents a methodology for modelling and analysing the combined effect of these errors on a machined feature. Deviation of a machined feature due to the combined errors is expressed in terms of the small displacement torsor parameters. Given a tolerance on the machined feature, constraints are specified for that feature to establish a relationship between the tolerance zone of the feature and the torsor parameters. These constraints provide boundaries within which the machined feature must lie. This is used for tolerance analysis of the machined feature. A case study example was used to illustrate the approach. An experimental system was also set up to verify the analytical model. The results show that this approach offers an effective means for fixturing tolerance analysis.
Analytical solution of a two-dimensional stagnation flow in the vicinity of a shrinking sheet by means of the homotopy analysis method
Authors: Kimiaeifar A , Bagheri G H , Rahimpour M , Mehrabian M A
Published: May 2009

In this article, stagnation flow in the vicinity of a shrinking sheet is studied. A similarity transformation is employed to reduce the Navier—Stokes equations to a set of non-linear ordinary differential equations. These equations are then solved analytically by means of the homotopy analysis method (HAM). The results obtained were shown to compare well with the numerical results available in the literature for the same problem. Close agreement between the two sets of results indicates the accuracy of the HAM. The method can predict the flow field in all vertical distances from the sheet, and is also able to control the convergence of the solution. The numerical solution of the similarity equations is also developed and the results are in good agreement with the analytical results based on the HAM.
Three-dimensional particle simulation of the plume of a pulsed plasma thruster
Authors: Qian Z , Du Z , Wang P
Published: May 2009

The plume characteristics of a pulsed plasma thruster (PPT) are considered necessary in the evaluation of plume/spacecraft interactions. In this article, the rarefied plasma plume of a laboratory PPT is characterized. First, a three-dimensional (3D) physical model with boundary conditions is presented. Then, the particle-in-cell and direct simulation Monte-Carlo hybrid methods are employed to study the flow field. The profiles of the plasma density and potential and their variations versus time are analysed. Also, the computational results are compared with experiment data as well as with results from existing two-dimensional (2D) simulations. The comparisons show that the computational model can predict the electron density of plume in both parallel and perpendicular planes. It is also shown that the 3D predictions are more accurate than those of the 2D model. Analysis of the plume backflow indicates that less than one thousandth of the mass that is released from the solid propellant enters the backflow region at the end of a pulse period.
Synchronized attitude and translational motion control for spacecraft formation flying
Authors: Shan J
Published: May 2009

This article presents an adaptive synchronization control strategy for six-degree of freedom spacecraft formation flying based on the cross-coupling concept. The proposed strategy allows the spacecraft track the desired attitude and position trajectories, while simultaneously guarantees the synchronized motion among all spacecraft in formation. The generic synchronization error concept enables the design of a suitable synchronization strategy to obtain a desired synchronization performance. Simulation results of multiple spacecraft formation flying are conducted to verify the effectiveness of the proposed controller.
Analytical and experimental investigation of frequency of oscillation modes in combustion chambers of gas turbines
Authors: Akbari N , Seraj Mehdizadeh N , Ebrahimi R
Published: May 2009

Premixed combustion is widely used for simulation of combustion chambers of gas turbines, utilized for low NO x emission applications. However, this category of gas turbines is susceptible to combustion instability. Combustion instability has already been studied for industrial burners, ram jets, and pulse jets. But, with regard to modern gas turbines, there are limited works that are performed recently. Therefore, the main aim of this investigation is focused on thermo-acoustic instability modes in gas turbine combustion chambers. Both analytical and experimental methods are applied for this study. For this purpose, an experimental combustion chamber is designed and fabricated and various experiments are planned and performed in order to achieve the behaviour of combustion chamber during stable and unstable conditions. Moreover, an analytical method is applied and a computer code is written and elaborated for this purpose. Instability frequencies are derived experimentally and analytically and the results are compared with each other. Accordingly, good agreements are observed between the results. In addition, histograms, spectral diagrams, and wave forms of thermo-acoustic instability are achieved experimentally.
Primary stability in reversed-anatomy glenoid components
Authors: Hopkins A R , Hansen U N
Published: May 2009

Reversed-anatomy shoulder replacement is advocated for patients with poor rotator cuff condition, for whom an anatomical reconstruction would provide little or no stability. Modern generations of this concept appear to be performing well in the short-term to midterm clinical follow-up. These designs are almost always non-cemented, requiring a high degree of primary stability to encourage bone on-growth and so to establish long-term fixation. Six different inverse-anatomy glenoid implants, currently on the market and encompassing a broad range of geometrical differences, were compared on the basis of their ability to impart primary stability through the minimization of interface micromotions. Fixing screws were only included in the supero-inferior direction in appropriate implants and were always inclined at the steepest available angle possible during surgery (up to a maximum of 30°). The extent of predicted bony on-growth was, of course, highly dependent on the threshold for interface micromotion. In some instances an additional 30 per cent of the interface was predicted to promote bone on-growth when the threshold was raised from 20 μm to 50 μm. With maximum thresholds of micromotion for bone on-growth set to 30 μm, the Zimmer Anatomical device was found to be the most stable of the series of the six designs tested herein, achieving an additional 3 per cent (by surface area) of bone on-growth above the closest peer product (Biomet Verso). When this threshold was raised to 50 μm, the Biomet Verso design was most stable (3 per cent above the second-most stable design, the Zimmer Anatomical). Peak micromotions were not a good indicator of the predicted area of bone on-growth and could lead to some misinterpretation of the implant's overall performance. All but one of the implants tested herein provided primary stability sufficient to resist motions in excess of 150 μm at the interface.
Characterization of lubricants for metal forming by means of an oscillating tribo-test-rig
Authors: Monetti C , Ilo S , Lebersorger T
Published: May 2009

Cold metal forming is a versatile and very efficient technology in the manufacture of metal components. In cold metal forming processes high pressure is generated at the tool-workpiece interface, so that good lubrication is required to reduce wear. This improves tool life and the quality of products. The lubricants used in the forming processes usually contain appropriate basis oils with anti-wear (AW) and extreme pressure (EP) additives.

In order to examine how wear occurs during cold metal forming, the SRV (Schwingung Reibung Verschleiss) reciprocating-sliding tribometer equipped with a cylinder-on-disc line- contact testing system was adapted and used to characterize lubricant behaviour. Friction coefficient and wear rate were determined under progressively increasing load conditions. The final worn volumes of the flat and the cylinder were evaluated by using optical microscopy methods. The measurement system was validated by replicate tests using some commercially available forming lubricants as reference in a load range of 100-1000 N.

The oscillating tribo-test-rig can be used to characterize lubricants for cold metal forming processes by testing the combined effects of different additive systems and their interaction with contacting materials.
Circulating Methylated SEPT9 DNA in Plasma Is a Biomarker for Colorectal Cancer
Authors: deVos Theo , Tetzner Reimo , Model Fabian , Weiss Gunter , Schuster Matthias , Distler Jürgen , Steiger Kathryn V , Grützmann Robert , Pilarsky Christian , Habermann Jens K , Fleshner Phillip R , Oubre Benton M , Day Robert , Sledziewski Andrew Z , Lofton-Day Catherine
Published: May 2009

Background: The presence of aberrantly methylated SEPT9 DNA in plasma is highly correlated with the occurrence of colorectal cancer. We report the development of a new SEPT9 biomarker assay and its validation in case–control studies. The development of such a minimally invasive blood-based test may help to reduce the current gap in screening coverage.

Methods: A new SEPT9 DNA methylation assay was developed for plasma. The assay comprised plasma DNA extraction, bisulfite conversion of DNA, purification of bisulfite-converted DNA, quantification of converted DNA by real-time PCR, and measurement of SEPT9 methylation by real-time PCR. Performance of the SEPT9 assay was established in a study of 97 cases with verified colorectal cancer and 172 healthy controls as verified by colonoscopy. Performance based on predetermined algorithms was validated in an independent blinded study with 90 cases and 155 controls.

Results: The SEPT9 assay workflow yielded 1.9 μg/L (CI 1.3–3.0) circulating plasma DNA following bisulfite conversion, a recovery of 45%–50% of genomic DNA, similar to yields in previous studies. The SEPT9 assay successfully identified 72% of cancers at a specificity of 93% in the training study and 68% of cancers at a specificity of 89% in the testing study.

Conclusions: Circulating methylated SEPT9 DNA, as measured in the new mSEPT9 assay, is a valuable biomarker for minimally invasive detection of colorectal cancer. The new assay is amenable to automation and standardized use in the clinical laboratory.
Identification and Prevention of Genotyping Errors Caused by G-Quadruplex– and i-Motif–Like Sequences
Authors: Wenzel Jürgen J , Rossmann Heidi , Fottner Christian , Neuwirth Stefan , Neukirch Carolin , Lohse Peter , Bickmann Julia K , Minnemann Timo , Musholt Thomas J , Schneider-Rätzke Brigitte , Weber Matthias M , Lackner Karl J
Published: May 2009

Background: Reliable PCR amplification of DNA fragments is the prerequisite for most genetic assays. We investigated the impact of G-quadruplex– or i-motif–like sequences on the reliability of PCR-based genetic analyses.

Methods: We found the sequence context of a common intronic polymorphism in the MEN1 gene (multiple endocrine neoplasia I) to be the cause of systematic genotyping errors by inducing preferential amplification of one allelic variant [allele dropout (ADO)]. Bioinformatic analyses and pyrosequencing-based allele quantification enabled the identification of the underlying DNA structures.

Results: We showed that G-quadruplex– or i-motif–like sequences can reproducibly cause ADO. In these cases, amplification efficiency strongly depends on the PCR enzyme and buffer conditions, the magnesium concentration in particular. In a randomly chosen subset of candidate single-nucleotide polymorphisms (SNPs) defined by properties deduced from 2 originally identified ADO cases, we confirmed preferential PCR amplification in up to 50% of the SNPs. We subsequently identified G-quadruplex and i-motifs harboring a SNP that alters the typical motif as the cause of this phenomenon, and a genomewide search based on the respective motifs predicted 0.5% of all SNPs listed by dbSNP and Online Mendelian Inheritance in Man to be potentially affected.

Conclusions: Undetected, the described phenomenon produces systematic errors in genetic analyses that may lead to misdiagnoses in clinical settings. PCR products should be checked for G-quadruplex and i-motifs to avoid the formation of ADO-causing secondary structures. Truly affected assays can then be identified by a simple experimental procedure, which simultaneously provides the solution to the problem. .
Energy Policy: Concepts, Actors, Instruments and Recent Developments
Authors: Prontera Andrea
Published: May 2009

The article analyses the specific features of energy policy-making, by exploring the relevant dimensions of the matters and the interdependence between energy policy and other sectors. A recognition of the evolution of energy policy  and of the policy change which occurred in recent years  is provided, as a starting point for applying the tools of policy studies to the analysis of energy policy-making. Two different types are then identified: the external policy-making concerning security matters; and the internal policy-making concerning organizational and market-related issues. It will be seen that each type of policy-making is characterized by a particular policy sub-system with its own actors, instruments, arenas and dynamics.
Effect of remifentanil hydrochloride administered via constant rate infusion on the minimum alveolar concentration of isoflurane in cats
Authors: Ferreira Tatiana H. , Aguiar Antonio J. A. , Valverde Alexander , Neto Francisco J. Teixeira , Steagall Paulo V. M. , Soares João H. N.
Published: May 2009

Objective—To evaluate the effects of increasing doses of remifentanil hydrochloride administered via constant rate infusion (CRI) on the minimum alveolar concentration (MAC) of isoflurane in cats.

Animals—6 healthy adult cats.

Procedures—For each cat, 2 experiments were performed (2-week interval). On each study day, anesthesia was induced and maintained with isoflurane; a catheter was placed in a cephalic vein for the administration of lactated Ringer's solution or remifentanil CRIs, and a catheter was placed in the jugular vein for collection of blood samples for blood gas analyses. On the first study day, individual basal MAC (MACBasal) was determined for each cat. On the second study day, 3 remifentanil CRIs (0.25, 0.5, and 1.0 μg/kg/min) were administered (in ascending order); for each infusion, at least 30 minutes elapsed before determination of MAC (designated as MACR0.25, MACR0.5, and MACR1.0, respectively). A 15-minute washout period was allowed between CRIs. A control MAC (MACControl) was determined after the last remifentanil infusion.

Results—Mean ± SD MACBasal and MACControl values at sea level did not differ significantly (1.66 ± 0.08% and 1.52 ± 0.21%, respectively). The MAC values determined for each remifentanil CRI did not differ significantly. However, MACR0.25, MACR0.5, and MACR1.0 were significantly decreased, compared with MACBasal, by 23.4 ± 7.9%, 29.8 ± 8.3%, and 26.0 ± 9.4%, respectively.

Conclusions and Clinical Relevance—The 3 doses of remifentanil administered via CRI resulted in a similar degree of isoflurane MAC reduction in adult cats, indicating that a ceiling effect was achieved following administration of the lowest dose.
Assessment of cytologic evaluation of preputial epithelial cells as a diagnostic test for detection of adrenocortical disease in castrated ferrets
Authors: Protain Holly J. , Kutzler Michelle A. , Valentine Beth A.
Published: May 2009

Objective—To determine whether results of cytologic evaluation of preputial epithelial cells correspond to results of a serum endocrine hormone assay and clinical signs associated with adrenocortical disease in castrated ferrets.

Animals—13 clinically normal ferrets and 8 ferrets with signs of adrenocortical disease.

Procedures—Blood and preputial lavage samples were collected from each ferret. Serum samples were submitted to the University of Tennessee Veterinary Diagnostic Laboratory for performance of an endocrine hormone assay. Differential epithelial cell counts were performed on preputial lavage samples to determine the percentage of cornified cells. Results of cytologic evaluation were compared with results of the endocrine hormone assay and clinical status of ferrets.

Results—The percentage of cornified preputial epithelial cells was not significantly correlated with serum 17B-estradiol or androstenedione concentration but was significantly correlated with serum 17-hydroxyprogesterone concentration (r = 0.60). The percentage of cornified preputial epithelial cells was higher in ferrets with clinical signs of adrenocortical disease (mean ± SD, 71.3 ± 16.9%) than in clinically normal ferrets (55.5 ± 19.0%).

Conclusions and Clinical Relevance—Cornification of preputial epithelial cells was correlated with an increase in serum 17-hydroxyprogesterone concentration as well as clinical signs of adrenocortical disease in castrated ferrets. Additional investigation is needed to elucidate the mechanism of preputial epithelial cell cornification in castrated ferrets.
Comparison of three treatment regimens for sheep and goats with caseous lymphadenitis
Authors: Washburn Kevin E. , Bissett Wesley T. , Fajt Virginia R. , Libal Melissa C. , Fosgate Geoffrey T. , Miga Joseph A. , Rockey Kristine M.
Published: May 2009

Objective—To compare the effectiveness of 3 treatment regimens for small ruminants with caseous lymphadenitis.

Design—Randomized clinical trial.

Animals—44 client-owned sheep and goats.

Procedures—Aspirates were obtained from 48 lesions of 44 enrolled animals and submitted for bacterial culture. Animals were randomly assigned to 1 of 3 treatment groups. Treatment for group A (n = 15 lesions) consisted of opening, draining, and flushing the lesions and SC administration of procaine penicillin G. Treatment for group B (n = 15 lesions) consisted of closed-system lavage and intralesional administration of tulathromycin. Treatment for group C (n = 18 lesions) consisted of closed-system lavage and SC administration of tulathromycin. All animals were reexamined approximately 1 month after treatment, unless treatment failure was detected prior to that time.

Results—43 animals with lesions had positive results (Corynebacterium pseudotuberculosis) for bacterial culture. Proportions of lesions that had resolution of infection by 1 month after treatment did not differ significantly among the treatment groups (group A, 13/14 [92.9%]; 95% confidence interval [CI], 69.5% to 99.6%; group B, 10/12 [83.3%]; 95% CI, 54.9% to 97.1%; and group C, 14/17 [82.4%]; 95% CI, 59.1% to 95.3%).

Conclusions and Clinical Relevance—Acceptable alternatives to opening, draining, and flushing of lesions may exist for treatment of sheep and goats with caseous lymphadenitis. Use of tulathromycin and penicillin in this study constituted extralabel drug use, which would require extended withholding times before milk or meat of treated sheep and goats can be sold for human consumption.
Looking Forward in Records of Young Adults who were Convicted of Homicide or Assault as Youth: Risks for Reoffending
Authors: Zagar Robert John , Grove William M. , Busch Kenneth G. , Hughes John Russell , Arbit Jack
Published: May 2009

To assess risks of violent offending in young adults, 425 Delinquent Assaulters ( M age = 14.1 yr., SD= 1.7; 77 girls, 348 boys) were matched with 425 Nonviolent Delinquents. Analysis of data from court, school, and medical records used Shao's bootstrapped logistic regressions. Predictors of Assaulter status were poorer executive function ( OR = 0.97) and prior court contacts for violent offenses ( OR = 3.5e+ 23; AUC=.97; 95% CI = .82−.99). Looking in records backward 4 years ( M = 4.1, SD = 2.6) and forward 10 years to mean age 24.5 yr. ( SD = 2.1), adults were classified as Homicidal (8%, n = 69); Delinquent Assaulters Later Adult Assaulters (10%, n = 86); Delinquent Assaulters Later Noncriminals (32%, n = 270); Nonviolent Delinquents Later Nonviolent Criminals (10%, n = 87); and Nonviolent Delinquents Later Noncriminals (40%, n = 338). The Homicidal group ( n = 69) was compared to matched Control and Nonviolent Delinquent groups ( n = 69) using logistic regression. Predictors of Homicidal versus Control were poorer executive function and alcohol or substance abuse ( AUC=.97; 95%CI =.93−.99). Predictors of Homicidal versus Nonviolent Delinquents were unemployment, poorer executive function, and prior court contacts ( AUC=.98; 95%CI=.95−.99).
Looking forward in Records of Young Adults Convicted of Sexual Homicide, Rape, or Molestation as Youth: Risks for Reoffending
Authors: Busch Kenneth G. , Grove William M. , Arbit Jack , Zagar Robert John , Hughes John Russell , Bussell Robert E. , Bartikowski Boris
Published: May 2009

To assess the risks predicting reoffense, 223 Rapists ( M age = 14.2 yr., SD = 1.5; 25 girls, 198 boys) were matched with 223 Nonviolent Delinquents; risks were analyzed using logistic regression. The one predictor was prior court contacts ( OR = 1.55e+12; AUC = .99, 95%CI = .98−.99). 223 Molesters were similarly matched with 223 Nonviolent Delinquents; this comparison yielded three predictors: previous court contacts ( OR = 4.55e+23), poorer executive function ( OR = 2.01), and lower social maturity ( OR = .97; AUC = .98, 95% CI = .97−.99). Records for all cases (now M age = 24.2 yr., SD = 1.4) were reviewed forward 10 years and youth were classified into groups: Sexual Homicidal (1%, n = 7), Delinquent Rapists Later Adult Rapists (11%, n = 73), Delinquent Rapists (21%, n = 144), Delinquent Molesters Later Adult Molesters (10%, n = 69), Delinquent Molesters (23%, n = 153), Nonviolent Delinquent Later Nonviolent Adult Criminals (7%, n = 45), and Nonviolent Delinquents (27%, n = 178). Comparison of Sexual Homicidal cases ( n = 7) with their matched Controls ( n = 7) yielded one predictor, poorer executive function ( AUC = .89, 95 % CI = .71−.93). When Sexual Homicidal cases were matched with Nonviolent Delinquents, predictors were low social maturity and prior court contacts ( AUC = .81, 95%CI= .64−.93).
Summary of Studies of Abused Infants and Children Later Homicidal, and Homicidal, Assaulting later Homicidal, and Sexual Homicidal Youth and Adults
Authors: Zagar Robert John , Busch Kenneth G. , Grove William M. , Hughes John Russell
Published: May 2009

To study the risks of abuse, violence, and homicide, 5 studies of groups at risk for violence are summarized. 192 Abused Infants, 181 Abused Children, 127 Homicidal Youth, 425 Assaulters, 223 Rapists, and 223 Molesters were randomly selected and tracked in court, probation, medical, and school records, then compared with carefully matched groups of Controls and (in older groups) Nonviolent Delinquents. In adolescence or adulthood, these groups were classified into Later Homicidal ( N = 234), Later Violent or Nonviolent Delinquent, and Later Nondelinquent subgroups for more detailed comparisons. Shao's bootstrapped logistic regressions were applied to identify risks for commission of homicide. Significant predictors for all homicidal cases in these samples were number of court contacts, poorer executive function, lower social maturity, alcohol abuse, and weapon possession. Predictors for the 373 Abused cases (Infants and Children) were court contacts, injury, burn, poisoning, fetal substance exposure, and parental alcohol abuse. Predictors for the 871 Violent Delinquent cases (Assaulters, Rapists, Molesters) were court contacts, poorer executive function, and lower social maturity. Accuracies of prediction from the regressions ranged from 81% for homicidal sex offenders to 87 to 99% for other homicidal groups.
Comparing Early and Late Twentieth-Century Boston and Chicago Male Juvenile Offenders: What Changed?
Authors: Zagar Robert John , Hughes John Russell , Busch Kenneth G. , Arbit Jack
Published: May 2009

To investigate changes in characteristics of delinquents over time, randomly selected contemporary delinquents (Zagar, et al., 1980–1988; n = 2,031) were compared with 3 historical Chicago and Boston samples (Healy & Bonner, 1909–1915, n = 2,000; Healy & Bonner, 1917–1923, n = 2,000; Glueck & Glueck, 1917–1922, n = 1,000). All underwent physical, psychiatric, psychological, school, and social examinations. Contemporary delinquents had more assault, burglary, homicide, alcohol and substance abuse, gang membership, head injury, overdose, and single parents. Historical delinquent samples had more thieves and families with both biological parents. Historical delinquent mean IQ was 5 points below standardization average; modern delinquents were 22 points lower. Contemporary offenders were a greater portion of the county public school-aged population. Current more sensitive and specific examinations account for increases in observed overdoses and head injuries in the 1980s sample. Other demographic differences between contemporary and 3 historical delinquent samples were robust. Findings are discussed with respect to a need for early actuarial assessment and empirical treatment of the costliest delinquents: the dropouts, alcoholics, addicts, career delinquents-criminals, and homicide-prone youth.
Looking Forward in Records of Youth Abused as Infants: Risks for Homicidal, Violent, and Delinquent Offenses
Authors: Zagar Robert John , Grove William M. , Busch Kenneth G. , Hughes John Russell , Arbit Jack
Published: May 2009

To study risks for abuse and later homicidal behavior, 192 abused infants ( M age = 3.12 yr., SD = 1.48; 82 girls, 110 boys) and 192 controls were matched on demographics and examined; data discriminating abused and later homicidal cases were analyzed with Shao's bootstrapped logistic regression. Predictors of Abused status were injury, burn, poisoning, fetal substance exposure ( OR = 2.47), later parental or youth court contacts ( OR = 1.86e+12), and parental alcohol abuse (OR = .54; AUC = .99; 95% CI= .96−.99). Youth tracked through records 12 years (to M age = 12.17 yr., SD =1.89) were classified into Abused Later Homicidal (11%, n = 21), Abused Later Violent (14%, n = 27), Abused Later Delinquent (31%, n = 60), Abused Later Nondeliquent ( n = 44), and Control groups ( n = 192). Data were analyzed similarly. When the Abused Later Homicidal was contrasted with the Control group, predictors of homicide were three or more home/school moves ( OR = .78), illnesses ( OR = .90), and later court contacts ( OR= 1.75e+07; AUC=.99; 95% CI=.90−.98). When the Abused Later Homicidal was compared with the Abused Later Nondelinquent group, predictors of homicide were poorer executive function ( OR = 2.29) and later court contacts ( OR = 7.78e+06; AUC=.94; 95% CI= .90−.98).
Incidence of deep venous thrombosis after subarachnoid hemorrhage
Authors: Ray Wilson Z. , Strom Russel G. , Blackburn Spiros L. , Ashley William W. , Sicard Gregorio A. , Rich Keith M.
Published: May 2009

Object

The aim of this study was to determine the efficacy of venous ultrasonography in screening for deep venous thrombosis (DVT) after subarachnoid hemorrhage (SAH). A large cohort of patients who had suffered SAH was evaluated with the primary end points of ascertaining the incidence of asymptomatic DVT with venous Doppler ultrasonography screening and of identifying risk factors for the development of DVT and subsequent pulmonary embolism.

Methods

Data from patients with aneurysmal SAH who had been admitted to the neurosurgical intensive care unit (ICU) between December 2002 and October 2006 were retrospectively evaluated. Patients who had undergone surgical or endovascular treatment of an aneurysm following SAH and survived ≥ 15 days were included in the study.

Results

The overall incidence of DVT among the entire study cohort was 18%. A subgroup analysis identified all patients, with or without symptoms for DVT, who had undergone venous Doppler ultrasonography screening. The incidence of asymptomatic DVT was 24%. Univariate analysis of all patients revealed a significant correlation between the risk of DVT and Hunt and Hess grade (r = 0.38, p < 0.0001), Fisher grade (r = 0.31, p < 0.0001), total hospital stay (r = 0.49, p < 0.0001), and number of days in the ICU (r = 0.48, p < 0.0001). Multivariate analysis demonstrated that the total hospital stay and number of days in the ICU were significant predictors of DVT in all patients (p < 0.0001 and p < 0.0002, respectively). In the subgroup of screened patients, Hunt and Hess grade, total hospital stay, and number of days in the ICU were significant predictors of DVT. Although screened patients were more likely to have DVT (χ2 = 6.0976, p < 0.02), there was no significant difference in the incidence of DVT or pulmonary embolism between patients who did and those who did not undergo routine lower-extremity Doppler ultrasonography screening.

Conclusions

Routine compressive venous Doppler ultrasonography is an efficient, noninvasive means of identifying DVT as a screening modality in both symptomatic and asymptomatic patients following aneurysmal SAH. The ability to confirm or deny the presence of DVT in this patient population allows one to better identify the indications for chemoprophylaxis. Prophylaxis for venous thromboembolism in neurosurgical patients is common. Emerging literature and anecdotal experience have exposed risks of complications with prophylactic anticoagulation protocols. The identification of patients at high risk—for example, those with asymptomatic DVT—will allow physicians to better assess the role of prophylactic anticoagulation.
Graft selection in cerebral revascularization
Authors: Baaj Ali A. , Agazzi Siviero , van Loveren Harry
Published: May 2009

Cerebral revascularization constitutes an important treatment modality in the management of complex aneurysms, carotid occlusion, tumor, and moyamoya disease. Graft selection is a critical step in the planning of revascularization surgery, and depends on an understanding of graft and regional hemodynamics, accessibility, and patency rates. The goal of this review is to highlight some of these properties.
Management of anterior inferior cerebellar artery aneurysms: an illustrative case and review of literature
Authors: Bambakidis Nicholas C. , Manjila Sunil , Dashti Shervin , Tarr Robert , Megerian Cliff A.
Published: May 2009

Aneurysms of the anterior inferior cerebellar artery (AICA) are relatively rare among intracranial aneurysms. They can occur in 1 of 3 regions of the AICA: 1) craniocaudal (high or low riding), 2) mediolateral-premeatal (proximal), and 3) meatal-postmeatal (distal). The management strategies for treatment differ according to the location and configuration of the aneurysm. The existing body of neurosurgical literature contains articles published on aneurysms arising from the AICA near the basilar artery (BA), intracanalicular/meatal aneurysms, and distal AICA. Several therapeutic options exist, encompassing microsurgical and endovascular techniques. The authors describe a case of treatment involving a large BA-AICA aneurysm approached via exposure of the presigmoid dura using a retromastoid suboccipital craniectomy and partial petrosectomy. Treatment of these lesions requires detailed knowledge of the anatomy, and an anatomical overview of the AICA with its arterial loops and significant branches is presented, including a discussion of the internal auditory (labyrinthine) artery, recurrent perforating arteries, subarcuate artery, and cerebellosubarcuate artery. The authors discuss the various surgical approaches (retromastoid, far lateral, subtemporal, and transclival) with appropriate illustrations, citing the advantages and disadvantages in accessing these AICA lesions in relation to these approaches. The complications of these different surgical techniques and possible clinical effects of parent artery occlusion during AICA surgery are highlighted.
Introduction: Vascular Neurosurgery
Authors: Eddleman Christopher S. , Batjer H. Hunt , Lavine Sean
Published: May 2009

This issue of Neurosurgical Focus comes at an exciting and perhaps transformational time for those neuroscientists and clinicians involved in the study and treatment of complex cerebrovascular disease. Our diagnostic and therapeutic practices have seen dramatic advances. Imaging capabilities, both anatomical and functional, have improved at a dramatic rate and include neuronavigation modalities for intraoperative guidance, the application of new MR imaging sequences to cerebrovascular disease, and fluorescence angiography to aid in intraoperative decision making.
Fenestrated aneurysm clips in the surgical management of anterior communicating artery aneurysms: operative techniques and strategy
Authors: Zada Gabriel , Christian Eisha , Liu Charles Y. , Giannotta Steven L.
Published: May 2009

Object

Aneurysms of the anterior communicating artery (ACoA) can be a considerable challenge to treat surgically based on variations in the anatomy and morphological features of the ACoA complex. The fenestrated aneurysm clip can be a simple and practical tool in the operative management of ACoA aneurysms. The goal in this study was to characterize the particular surgical situations in which the use of a fenestrated clip facilitates the clip ligation of ACoA aneurysms.

Methods

The authors present their operative strategy and techniques for the use of fenestrated clips in the treatment of ACoA aneurysms.

Results

One hundred ninety-nine patients underwent surgical clipping of an ACoA aneurysm at the authors' institution between the years 1991 and 2008. Of these patients, fenestrated aneurysm clips were used in 20 cases (10%). The following structures were enclosed in the clip aperture: ipsilateral A2 artery, 12 patients (60%); ipsilateral A1 artery, 4 patients (20%); ipsilateral A1 artery plus recurrent artery of Heubner, 1 patient (5%); ACoA, 1 patient (5%); frontopolar artery, 1 patient (5%); and no structures, 1 patient (5%). Aneurysms approached from the left side more frequently required fenestrated clips than did right-sided aneurysms (80 vs 20%, p = 0.0073). In all cases, patency of the A2 vessels was confirmed on postoperative angiography. In 2 patients, small remnant aneurysm necks were identified on postoperative angiography.

Conclusions

The use of fenestrated aneurysm clips can minimize tedious and potentially dangerous dissection of adherent branch vessels, while maintaining the integrity of structures placed within the clip aperture. The ACoA aneurysms pointing in a superior direction are more likely to require clip fenestration around the A2 vessel, whereas those pointing in an inferior direction are more likely to require clip fenestration around the A1 vessel. The parallel approximation of the fenestrated clip blades makes them especially useful in the treatment of large or giant aneurysms.
Delayed stenosis as a consequence of angioplasty for subarachnoid hemorrhage–induced vasospasm
Authors: Merchant Akeel , Drazin Doniel , Dalfino John , Yamamoto Junichi , Boulos Alan S.
Published: May 2009

The authors report a case of restenosis in the bilateral internal carotid arteries (ICAs) following angioplasty for cerebral vasospasm. This 53-year-old woman suffering subarachnoid hemorrhage due to a ruptured posterior communicating artery aneurysm had severe vasospasm and underwent angioplasty of the left and right ICAs and middle cerebral arteries. Two months later, a follow-up CT angiogram revealed bilateral ICA stenoses.

Transluminal angioplasty leads to long-term connective tissue damage in the medial and adventitial layers from the disruption of the arrangement of collagen fibers due to stretching and tearing, resulting in loss of transmission of contractile forces. Furthermore, following endothelial cell denudation and stretching and rupture of internal elastic lamina from angioplasty, reendothelialization of the intimal layer composed of smooth muscle cells may also explain the contractile properties of restenosis. Other factors such as macrophage-induced inflammation and reactive oxygen species accumulation may also contribute to restenosis. This is the second reported case of restenosis following angioplasty to treat vasospasm, although restenosis is a known complication of angioplasty for treatment of atherosclerosis. In addition, this is the first case of restenosis in the bilateral ICAs following angioplasty for vasospasm. This report presents an illustrative case study and reviews the pathophysiology of angioplasty and restenosis.