bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mixed‐mode fatigue crack growth of thin aluminium panels with single‐side repair using experimental and numerical methods
Authors: HOSSEINI‐TOUDESHKY H. , MOHAMMADI B. , BAKHSHANDEH S. 
Published: June 2007

ABSTRACTIn this paper, experimental and numerical fatigue crack growth of thin aluminium panels containing a central inclined crack of 45° with single‐side glass/epoxy composite patch are performed. Effects of patch lay‐up configuration on the restarting crack growth (crack re‐initiation) life and crack growth rate of the repaired panels are investigated. The obtained experimental results are compared with those predicted using finite element analysis based on both mid‐plane and unpatched surface fracture parameters. In the finite elements analyses, it is assumed that the crack‐front remains perpendicular to the panel's surfaces during its propagation. It is shown that the finite element crack re‐initiation and propagation lives predictions using the unpatched surface results are too conservative. However, the finite element mid‐plane results lead to a non‐conservative life prediction. It is experimentally shown that, the most effective patch lay‐up configurations to retard the crack growth of the repaired panels is [−45/+45]2; however, the most life extension including the crack propagation cycles belongs to the patch lay‐up of [904]. It is also shown that using the asymmetric patch lay‐up configuration similar to [902/02] with a proper bonding process may lead to a very slow crack growth rate, even slower than the patch lay‐up of [904].
Fatigue crack growth of filled rubber under constant and variable amplitude loading conditions
Authors: HARBOUR RYAN J. , FATEMI ALI , MARS WILL V. 
Published: June 2007

ABSTRACTService conditions experienced by rubber components often involve cyclic loads which are more complex than a constant amplitude loading history. Consequently, a model is needed for relating the results of constant amplitude characterization of fatigue behaviour to the effects of variable amplitude loading signals. The issue is explored here via fatigue crack growth experiments on pure shear specimens conducted in order to evaluate the applicability of a linear crack growth model equivalent to Miner's linear damage rule. This model equates the crack growth rate for a variable amplitude signal to the sum of the constant amplitude crack growth rates associated with each individual cycle. The variable amplitude signals were selected to show the effects of R‐ratio (ratio of minimum to maximum energy release rate), load level, load sequence, and dwell periods on crack growth rates. In order to distinguish the effects of strain crystallization on crack growth behaviour, two filled rubber compounds were included: one that strain crystallizes, natural rubber, and one that does not, styrene‐butadiene rubber. The linear crack growth model was found to be applicable in most cases, but a dwell effect was observed that is not accounted for by the model.
Fatigue strength of a typical ship structural detail: tests and calculation methods
Authors: RIZZO C. M. , TEDESCHI R. A. 
Published: June 2007

ABSTRACTIn previous years, several large‐scale specimens have been fatigue tested in the Ship Structures laboratory of the Dipartimento di Ingegneria Navale e Tecnologie Marine (DINAV) of the University of Genova (Italy). They represent the crossing of a T‐shaped beam into deep web plates, simulating either a primary supporting member or bulkhead plating. Each specimen is characterized by two joints, both watertight but with different geometry.The purpose of this paper is to review all the available test results using calculation methods for fatigue strength of welded structural details, namely: nominal stress approach, local stress approaches and the fracture mechanics approach.Test results allow SN curves to be drawn which can be used for these and similar details, quite common in shipbuilding. Moreover, calibration of stress concentration factors and coefficients in the various fatigue life calculation methods is possible using the experimental data.
Coding of movement‐ and force‐related information in primate primary motor cortex: a computational approach
Authors: Guigon Emmanuel , Baraduc Pierre , Desmurget Michel 
Published: June 2007

AbstractCoordinated movements result from descending commands transmitted by central motor systems to the muscles. Although the resulting effect of the commands has the dimension of a muscular force, it is unclear whether the information transmitted by the commands concerns movement kinematics (e.g. position, velocity) or movement dynamics (e.g. force, torque). To address this issue, we used an optimal control model of movement production that calculates inputs to motoneurons that are appropriate to drive an articulated limb toward a goal. The model quantitatively accounted for kinematic, kinetic and muscular properties of planar, shoulder/elbow arm‐reaching movements of monkeys, and reproduced detailed features of neuronal correlates of these movements in primate motor cortex. The model also reproduced qualitative spatio‐temporal characteristics of movement‐ and force‐related single neuron discharges in non‐planar reaching and isometric force production tasks. The results suggest that the nervous system of the primate controls movements through a muscle‐based controller that could be located in the motor cortex.
Dexmedetomidine for pediatric MRI sedation: a review of a series of cases
Authors: HEARD CHRISTOPHER M.B. , JOSHI PRASHANT , JOHNSON KRISTIN 
Published: June 2007

SummaryBackground:  The aim of this review was to determine whether dexmedetomidine alone provided satisfactory conditions for children undergoing magnetice resonance imaging (MRI).Methods:  A retrospective review of 21 patients was undertaken, (age range: 1–8 years, weight 10–27 kg) who received dexmedetomidine to provide deep sedation for an MRI procedure.Results:  In the initial eight patients who received dexmedetomidine (bolus 0.5–1.5 mg·kg−1 and infusion rate 1–1.5 mg·kg−1·h−1) by itself, movement occurred in five of them, even when the maximum suggested dose was used (1 μg·kg−1·h−1). Midazolam (0.1 mg·kg−1) i.v. was given as an adjunct to the following 13 patients (dexemdetomidine doses were lower: bolus 1 mg·kg−1, infusion 0.5–1 mg·kg−1·h−1). Only one patient moved within this group. The mean time to discharge postprocedure was 90 min. There were no differences with respect to recovery or discharge times between those who did or did not receive midazolam. No cardiac or respiratory complications were noted.Conclusions:  The use of dexmedetomidine for MRI sedation by itself was more unpredictable than anticipated from the published case reports of its use.
How well do pediatric anesthesiologists agree when assigning ASA physical status classifications to their patients?1
Authors: BURGOYNE LAURA L. , SMELTZER MATTHEW P. , PEREIRAS LILIA A. , NORRIS ANGELA L. , ARMENDI ALBERTO J. DE 
Published: June 2007

SummaryBackground:  The scope and application of the American Society of Anesthesiologists Physical Status (ASA PS) classification has been called into question and interobserver consistency even by specialist anesthesiologists has been described as only fair. Our purpose was to evaluate the consistency of the application of the ASA PS amongst a group of pediatric anesthesiologists.Methods:  We randomly selected 400 names from the active list of specialist members of the Society for Pediatric Anesthesia. Respondents were asked to rate 10 hypothetical pediatric patients and answer four demographic questions.Results:  We received 267 surveys, yielding a response rate of 66.8% and the highest number of responses in any study of this nature. The spread of answers was wide across almost all cases. Only one case had a response spread of only two classifications, with the remaining cases having three or more different ASA PS classifications chosen. The most variability was found for a hypothetical patient with severe trauma, who received five different ASA PS classifications. The Modified Kappa Statistic was 0.5, suggesting moderate agreement. No significant difference between the private and academic anesthesiologists was found (P = 0.26).Conclusions:  We present the largest evaluation of interobserver consistency in ASA PS in pediatric patients by pediatric anesthesiologists. We conclude that agreement between anesthesiologists is only moderate and suggest standardizing assessment, so that it reflects the patient status at the time of anesthesia, including any acute medical or surgical conditions.
A comparison of control results for the alien invasive woodwasp, Sirex noctilio, in the southern hemisphere
Authors: Hurley Brett P. , Slippers Bernard , Wingfield Michael J. 
Published: June 2007

Abstract1 Sirex noctilio has resulted in one of the most damaging biological invasions of pine forestry in the southern hemisphere.2 An intensive, integrated control programme has been developed for this pest and is generally considered very successful. However, a critical comparison of S. noctilio infestations and control efforts throughout the southern hemisphere reveals that control has not been uniformly effective. Of particular concern is the apparently unexplained variability in establishment and success of biological control agents, including various parasitic wasps and the parasitic nematode Deladenus siricidicola.3 An overlooked aspect in the establishment of the biological control interventions for S. noctilio is the potential influence of genetic bottlenecks on the ability of the agents to adapt to different environments and different populations of S. noctilio.4 Despite established biological control agents, stress in forests caused by silvicultural practices or the environment will predispose trees to heavy infestation. Unfortunately, improved silvicultural practices are not always economically feasible and environmental changes are often unavoidable.5 Sirex noctilio continues to pose a serious threat to pine forestry in many areas. Despite extensive earlier research into a single integrated control for S. noctilio, it is important to recognize that such a strategy will probably require significant local adaptation in new areas of infestation and over time.
Raman‐FISH: combining stable‐isotope Raman spectroscopy and fluorescence in situ hybridization for the single cell analysis of identity and function
Authors: Huang Wei E. , Stoecker Kilian , Griffiths Robert , Newbold Lyndsay , Daims Holger , Whiteley Andrew S. , Wagner Michael 
Published: June 2007

SummaryWe have coupled fluorescence in situ hybridization (FISH) with Raman microscopy for simultaneous cultivation‐independent identification and determination of 13C incorporation into microbial cells. Highly resolved Raman confocal spectra were generated for individual cells which were grown in minimal medium where the ratio of 13C to 12C content of the sole carbon source was incrementally varied. Cells which were 13C‐labelled through anabolic incorporation of the isotope exhibited key red‐shifted spectral peaks, the calculated ‘red shift ratio’ (RSR) being highly correlated with the 13C‐content of the cells. Subsequently, Raman instrumentation and FISH protocols were optimized to allow combined epifluorescence and Raman imaging of Fluos, Cy3 and Cy5‐labelled microbial populations at the single cell level. Cellular 13C‐content determinations exhibited good congruence between fresh cells and FISH hybridized cells indicating that spectral peaks, including phenylalanine resonance, which were used to determine 13C‐labelling, were preserved during fixation and hybridization. In order to demonstrate the suitability of this technology for structure–function analyses in complex microbial communities, Raman‐FISH was deployed to show the importance of Pseudomonas populations during naphthalene degradation in groundwater microcosms. Raman‐FISH extends and complements current technologies such as FISH‐microautoradiography and stable isotope probing in that it can be applied at the resolution of single cells in complex communities, is quantitative if suitable calibrations are performed, can be used with stable isotopes and has analysis times of typically 1 min per cell.
Intra‐operative pathological diagnosis of chronic ulcerative colitis in the two stage ileal pouch anal anastomosis
Authors: Ravishankar H. R. , Armstrong G. R. , Scott N. A. 
Published: June 2007

AbstractObjective  The definitive diagnostic biopsy for chronic ulcerative colitis (CUC) is the colon itself. Simultaneous colectomy and ileal pouch anal anastomosis (IPAA) means that the colon only becomes available for pathological assessment intra‐operatively. We examined the role of intra‐operative pathological assessment including frozen section in distinguishing between CUC and Crohn's colitis, inpatients undergoing simultaneous colectomy and IPAA.Method  Prospective study of 13 patients undergoing simultaneous colectomy and IPAA between Jan 1992 and April 1999. Resected colon was sent for pathological assessment intra‐operatively in all 13 patients. Comparison was made between final histology and frozen section. Patient outcome and pouch function was recorded prospectively.Results  Thirteen patients, M:F 5:8, mean age 41 years (range 20–56). Intra‐operative pathological assessment including frozen section diagnosed CUC in nine patients, Crohn's disease in two patients and indeterminate colitis in two patients. The two Crohn's patients had subtotal colectomy and ileostomy. The nine CUC patients and two indeterminate colitis patients underwent IPAA. There was complete agreement between intra‐operative assessment including frozen section and the final histopathology. At a median follow up of 31 months (8–58 months) all pouches were intact with good function. There has been no evidence of Crohn's disease on subsequent pouchoscopy and pouch biopsy.Conclusions  Pathological assessment, including frozen section of the colon, intra‐operatively is a useful adjunct to surgical decision making in those patients undergoing simultaneous colectomy and IPAA.
Microsatellite instability and MLH1 hypermethylation – incidence and significance in colorectal polyps in young patients
Authors: Koh D. C. , Luchtefeld M. A. , Kim D. G. , Attal H. , Monroe T. , Ingersoll K. 
Published: June 2007

AbstractObjective  Microsatellite instability (MSI) is observed in most hereditary nonpolyposis colorectal cancer‐related colorectal cancers (CRC). The original Bethesda criteria recommends MSI testing in patients ≤40 years diagnosed with adenomas. We aimed to determine the incidence of MSI and the presence of hypermethylation of the promoter site of the MLH1 gene in these polyps.Method  Patients aged ≤40 years diagnosed with colonic polyps removed endoscopically from 1998 to 2003 were identified and their charts reviewed. DNA extractions were performed and tested for MSI at the Bethesda Consensus recommended loci. Samples were characterized by immunohistochemical staining of the four mismatch repair (MMR) proteins. MLH1 hypermethylation was assessed using a real‐time methylation‐specific polymerase chain reaction (PCR). The appropriate statistical analyses were applied.Results  23 patients with 38 polyps were analysed. Eight patients had a positive family history colorectal polyp, 11 a family history of CRC. No significant correlation between a family history of colorectal polyps or cancer and polyp location was found. About 53% of the polyps were tubulo‐adenomas and 27% tubulovillous adenomas. Immunohistochemistry (IHC) staining revealed appropriate expression of the MMR proteins in all samples. None of the polyps exhibited MSI. MLH1 ‘A’ hypermethylation was present in 16% of the polyps. No hypermethylation was observed at region ‘C’. A positive family history of colorectal polyps and cancer were associated with a higher incidence of MLH1 ‘A’ hypermethylation. There was no determinable correlation between the clinico‐pathological features of the polyp with MLH1 hypermethylation.Conclusion  MLH1 HM was found in approximately 16% of polyps found in young patients and represents one of the epigenetic changes that may result in the subsequent progression to carcinoma along an accelerated sequence. The yield of MSI testing in these patients is low and is not recommended.
A small rise in CEA is sensitive for recurrence after surgery for colorectal cancer
Authors: Irvine T. , Scott M. , Clark C. I. 
Published: June 2007

AbstractObjective  Rise in carcinoembryonic antigen (CEA) above normal limits can indicate recurrent colorectal cancer. The aim of this study was to evaluate whether a small rise in CEA, even within normal limits was a sensitive indicator of recurrence.Method  150 patients aged 22–87 years were followed up for a mean of 27 months after colorectal surgery with CEA 3 and 6 monthly computerized tomography. We analysed whether a rise in CEA > 1 ng/ml correlated with recurrence of metastases.Results  Forty‐six of 139 patients in final analysis had recurrent disease. A rise in CEA > 1 had a predictive value of 74% for recurrence or metastases (sensitivity 80%, specificity 86%). These findings were similar whether or not the CEA was normal preoperatively.Conclusion  If CEA is measured after surgery for colorectal cancer, a rise of >1 in the patient's postoperative value is predictive for recurrence or metastases with an overall sensitivity of 80% and specificity of 86%. Previous studies have recognized the role of large rises in CEA in predicting recurrence but this study shows that small changes in CEA may be significant even if these levels would be traditionally within ‘normal’ limits.
Can a failed ileal pouch anal anastomosis be left in situ?
Authors: Bengtsson J. , Börjesson L. , Willén R. , Öresland T. , Hultén L. 
Published: June 2007

AbstractObjective  Failure after ileal pouch‐anal anastomosis (IPAA) is reported with a frequency of 10–20%. The failed IPAA can be excised or defunctioned. Indications for excision and further management of an indefinitely diverted pouch are poorly described. The aim of the present investigation was to investigate pouch‐related problems and the histopathological pattern of the pouch mucosa in this group of patients.Method  In a cohort of 620 patients having IPAA with a median follow‐up of 14 years, 56 patients with failure were identified. The patients with defunctioned pouches were assessed with regard to pouch‐related problems and endoscopy with biopsies was performed. Biopsies were stained with haematoxylin‐eosin, PAS for neutral mucins and Alcian blue/high iron diamine for sialomucins/sulphomucins. Morphological changes were grouped into three types modified according to Veress and assessed for dysplasia.Results  Twenty‐two patients with an indefinitely diverted pouch were found. The follow‐up time after surgery for failure was 10 years. Thirteen patients completed the follow‐up. Except for two patients with pelvic/perineal pain, there were no clinical problems. The majority of patients displayed mild to moderate macroscopic signs of inflammation. Morphologically, findings ranged from a preserved mucosal pattern to intense inflammatory reaction. No case of dysplasia or carcinoma was found.Conclusion  Most patients with an indefinitely diverted pouch had no complaints regarding the pouch. There was no case of dysplasia. Indefinite diversion may be preferable to pouch excision, especially given the associated morbidity.
Ultrastructure of spermatozoa of scolecophidian snakes (Lepidosauria, Squamata)
Authors: Tavares‐Bastos L. , Cunha L. D. , Colli G. R. , Báo S. N. 
Published: June 2007

AbstractWe provide a detailed description of the sperm ultrastructure of three species of scolecophidian snakes, Leptotyphlops koppesi (Leptotyphlopidae), Typhlops reticulatus (Typhlopidae) and Liotyphlops beui (Anomalepididae), and make comparisons with the spermatozoa of Ramphotyphlops waitii (Typhlopidae) (Harding et al. 1995). All the species studied bear synapomorphies of Squamata and Serpentes. Among scolecophidian snakes, we identified eight polymorphic characters. Previous analyses of molecular and somatic morphological data provide equivocal solutions to the relationships among Anomalepididae, Leptotyphlopidae and Typhlopidae. A close relationship between Anomalepididae and Typhlopidae is corroborated by two characters of sperm ultrastructure, presence of an electron‐dense structure inside the proximal centriole and rounded mitochondria in transverse sections of T. reticulatus, Li. beui and R. waitii, whereas the absence of the ridge on the acrosome surface of Le. koppesi and T. reticulatus support a closer relationship between Typhlopidae and Leptotyphlopidae. The differences observed in sperm ultrastructure within Typhlopidae suggest the existence of snake intrafamilial polymorphism. The sperm characters of blindsnakes contain significant phylogenetic information and may provide important data for snake phylogenetic reconstructions.
Autopodial skeleton evolution in side‐necked turtles (Pleurodira)
Authors: Sánchez‐Villagra Marcelo R. , Winkler Jasmin D. , Wurst Linda 
Published: June 2007

AbstractCarpal and tarsal anatomy was documented based on the observation of dry skeletons of adult specimens representing 25 species in 15 genera and on data taken from the literature. In addition, histological sections and cleared and double‐stained autopodia of recently hatched and juvenile specimens representing seven chelid and pelomedusoid species were studied. There is much more morphological diversity in the manus than in the pes. Variation in autopodial skeletons includes: the astragalus and calcaneum are either separated or fused; fusion of distal carpals 3–4−5 or just 4–5; number of centralia in the carpus; and presence/absence of a pisiform and of an accessory radial element. The widespread and probably basal phalangeal formula for Pleurodira is 2.3.3.3.3. Deviations arePelomedusa subrufa, exhibiting a reduction to 2.2.2.2.2,Pelusiosspp. with one phalanx less in digit I and for one species in digit V as well, andAcanthochelys pallidipectoriswith an additional phalanx in the fourth finger. Six discrete characters itemizing some of the morphological variation observed were plotted on a composite pleurodire phylogeny, revealing not only homoplastic patterns but also the utility of some characters in supporting the monophyly of several clades. The pisiform is the last carpal element to ossify inChelus fimbriatus.We hypothesize that the so‐called fifth hooked metatarsal represents the fusion of distal tarsal 5 with metatarsal V. The accessory radial element that was occasionally present in the turtles examined may represent an atavism of the otherwise lost radiale of turtles.