bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Surgical Research Society of Australasia
Authors: Hall John C. , Ludbrook John 
Published: March 2003

Background:  The Surgical Research Society of Australasia (SRS) was established in 1961. The main intent was to promote surgical research, especially by young surgeons. The 50th Scientific Meetingof the SRS is due to be held in 2002.Methods:  Selected information was extracted from the programme books for the scientific meetings of the SRS, while historical material was retrieved from the Records and Archives Unit of the Royal Australasian College of Surgeons.Results:  There have been 48 scientific meetings of the SRS between1962 and 2000 inclusive, which have included the presentation of 1627 free papers. Forty‐one percent of the presenters (325/784)have done so on more than one occasion. The content of the presentations reflects the changing nature of surgical research during the last several decades.Conclusions:  The SRS has achieved its original intent of promoting surgical research.
Utility of white cell count and ultrasound in the diagnosis of acute appendicitis
Authors: Fergusson James A. E. , Hitos Kerry , Simpson Erroll 
Published: March 2003

Background:  Despite considerable advances in imaging, the diagnosis of acute appendicitis remains a clinical one. Nonetheless, knowledge of the characteristics of commonly used investigations for appendicitis may aid surgical decision‐making.Methods:  The pathology, full blood counts and ultrasounds of 1013 patients who underwent appendicectomy were reviewed and subjected to statistical analysis in order to determine diagnostic characteristics of various white cell count and ultrasound results.Results:  Total white cell count was found to be higher among patients with complicated appendicitis than those with simple appendicitis or normal appendices. Ultrasound was found to be less accurate than white cell count and neutrophil count in the diag­nosis of acute appendicitis by estimation of area under the receiver operator characteristic curve.Conclusion:  Knowledge of the meaning of various white cell count values may be invaluable in clinical decision‐making with regard to the diagnosis of acute appendicitis. Ultrasound is of limited utility in the diagnosis of appendicitis and should only be used in selected clinical situations.
Ductal carcinoma in situ of the breast in Singapore: Recent trends and clinical implications
Authors: Tan Kong‐Bing , Lee Hui‐Yin , Putti Thomas Choudary 
Published: March 2003

Background:  Breast ductal carcinoma in‐situ (DCIS) is increasingly being diagnosed as a result of screening mammography and better pathological recognition. With this and the rising breast cancer incidence in Singapore, DCIS is poised to become a bigger part of surgical practice. Principles of screening, diagnosis and management of DCIS have also been rapidly evolving. Against this background, a clinicopathological audit of recent cases of DCIS in our centre was performed.Methods:  Thirty‐eight cases of DCIS diagnosed in the period 1997−2000 were retrospectively analysed. Histological examination and immunohistochemical studies for oestrogen and progesterone receptor expression were performed.Results:  In the present study, DCIS was most common in the group of patients who were <50 years (58%) as compared to an American series’ where the corresponding group were ≥60 years (36%). Compared to a previous local study a decade ago, the present series showed that: (i) DCIS constituted a higher proportion of all breast cancers (6.4% vs 3.7%); (ii) a larger proportion of patients had disease detected by mammography (47% vs 10%); (iii) conservative breast excision was the only definitive surgery in 39% of cases (vs approximately 30%); and (iv) the mean size of lesions is smaller (13.5 mm vs 24.4 mm). Histologically, 26% of tumours were high grade, 71% had necrosis while 32% were oestrogen receptor (ER) and progesterone receptor (PR) negative. High grade tumours were associated with the presence of necrosis (P = 0.018), ER negativity (P = 0.015) and PR negativity (P = 0.001).Conclusions:  This study reveals interesting trends of DCIS in Singapore. The sizeable proportion of hormone receptor‐negative tumours may have implications for the hormonal adjuvant therapy of DCIS.
Optional sump: Novel use of triple lumen closed drainage system
Authors: Flanagan Sean , Logan David , Joseph Mark G. 
Published: March 2003

Background:  The debate over the use of drains in abdominal surgery is controversial. Selective drainage using a closed system is the method employed by most surgeons. There are, however, specific circumstances where different forms of drainage are required.Methods:  One hundred and sixty‐seven patients undergoing a mix of complex upper gastrointestinal surgery and colorectal surgery received an Axiom sump drain at the time of surgery. All side air vents were spigoted and the main lumina connected to a urine bag, with the option to convert to irrigation/suction as required.Results:  Two patients required conversion to irrigation/suction, because of ongoing egress of fluid. In both cases drainage ceased without surgical intervention. The remaining cases resolved with no complications related to the drain.Conclusion:  The technique described allows the use of a large bore, soft, gravity‐driven drain in cases where wound drainage is necessary. The closure of the ventilation ports maintains the advantage of a closed drainage system, yet allows for the conversion to a true sump system as required. This obviates the need for further drainage procedures.
Transanal endoscopic microsurgery: The first 50 cases
Authors: Farmer K. Chip , Wale Roger , Winnett Jason , Cunningham Ian , Grossberg Peter , Polglase Adrian 
Published: March 2003

Background:  Transanal endoscopic microsurgery is a form of minimally invasive rectal surgery first used at Cabrini Hospital in April 1997. This paper presents a prospective analysis of the first 50 cases with a median follow up of 33 months (range 20−48 months).Methods:  Prospective data was obtained from all cases between April 1997 and June 2000.Results:  Forty‐nine patients (30 men and 19 women) underwent 50 procedures. Thirty‐six had benign lesions and 14 malignant. The mean distance of the lower edge of the lesion from the anal verge was 8.7 cm. Three cases were converted to traditional transanal or transabdominal operations. Full‐thickness excision was performed on 26 patients and the rectal wound was closed in 13 cases. The mean duration of transanal endoscopic microsurgery was 67 min (range 20−175), with a mean blood loss of 24 mL (0−300). The mean diameter and area of the fixed specimen was 3.7 cm (1.5−9.8) and 11.4 cm2 (0.8−18.9), respectively. Complications included postoperative fever (3), urinary retention (1) and per rectum bleeding (1). There was one death. The mean length of stay was 4 days. Histology confirmed complete excision in 39 (78%) cases and there have been two instances of local recurrence of adenoma (5%).Conclusions:  Transanal endoscopic microsurgery is an effective, safe and cost‐beneficial procedure for local excision of selected lesions in the middle and upper thirds of the rectum.
Manufacturing and ultimate mechanical performance of carbon fibre‐reinforced epoxy composite suspension push‐rods for a Formula 1 racing car
Authors: Gilchrist M.D. , Curley L. 
Published: March 2003

ABSTRACTThe contemporary Formula 1 racing car makes extensive use of advanced composite materials in its construction. The design, manufacture and ultimate performance under compression of composite suspension push‐rods, that typically could be used in a Grand Prix racing car, are described in this present paper. An aerofoil cross‐section has been used based on different lay‐ups of carbon/epoxy composite. One push‐rod was manufactured using a uniform layup of unidirectional and woven cross‐ply prepreg, whilst a further three push‐rods were manufactured with a tapered layup of unidirectional and woven cross‐ply prepreg. Failure mechanisms including fibre microbuckling, fibre kinking and fibre fracture were observed, whilst comparisons have been made between the experimentally observed failure strains and those that were predicted using simple buckling theory. The ultimate compressive strength of the structural component was significantly less than that of the carbon/epoxy composite.
Fatigue striation formation in an Fe–3%Si alloy—effects of crystallographic orientation and neighbouring grains
Authors: Shimojo  , Uchida  , Turuoka  , Higo  
Published: March 2003

ABSTRACTIn order to know the criterion of fatigue striation formation, fatigue fracture surfaces and crack paths were investigated in Fe–3%Si single and bicrystals having various crystallographic orientations. On single crystals, striations were formed when the loading direction was close to a 〈110〉 direction. In this direction, the crack grew perpendicular to the loading direction. When the loading direction was near a 〈111〉 direction and the crack grew along an inclined plane, no striations were observed. Even in this orientation, when the crack grew perpendicular by necessity using bicrystals, striations were observed. This suggests that striations are not formed on a special crystallographic plane, but are formed when the fatigue crack plane is perpendicular to the loading direction regardless of crystallographic orientation.
Fatigue behaviour and life prediction of fibre reinforced metal laminates under constant and variable amplitude loading
Authors: WU X. R. , GUO Y. J. 
Published: March 2003

ABSTRACT Fatigue crack growth of fibre reinforced metal laminates (FRMLs) under constant and variable amplitude loading was studied through analysis and experiments. The distribution of the bridging stress along the crackline in centre‐cracked tension (CCT) specimen of FRMLs was modelled numerically, and the main factors affecting the bridging stress were identified. A test method for determining the delamination growth rates in a modified double cracked lap shear (DCLS) specimen was presented. Two models, one being fatigue‐mechanism‐based and the other phenomenological, were developed for predicting the fatigue life under constant amplitude loading. The fatigue behaviour, including crack growth and delamination growth, of glass fibre reinforced aluminium laminates (GLARE) under constant amplitude loading following a single overload was investigated experimentally, and the mechanisms for the effect of a single overload on the crack growth rates and the delamination growth rates were identified. An equivalent closure model for predicting crack‐growth in FRMLs under variable amplitude loading and spectrum loading was presented. All the models presented in this paper were verified by applying to GLARE under constant amplitude loading and Mini‐transport aircraft wing structures (TWIST) load sequence. The predicted crack growth rates are in good agreement with test results.
Failure analysis of gas turbine last stage bucket made of Udimet 500 superalloy
Authors: Mazur Z. , Kubiak J. , Mariño‐Lopez C. 
Published: March 2003

ABSTRACT This study presents the failure analysis of the 37.5 MW gas turbine third stage buckets made of Udimet 500 (U‐500) superalloy. The buckets experienced repetitive integral tip shroud fractures assisted by a low temperature (type II) hot corrosion. A detailed analysis of all elements which had an influence on the failure initiation was carried out, namely: the commensurate loss of a load bearing cross‐sectional area of the bucket tip shroud by the conversion of metal to the corrosion product (scale) and related increase in stress; the influence of the tip shroud microstructure, e.g. a presence of equiaxed and columnar grains, their distribution and orientation; evidence of the transgranular fracture initiation and intergranular creep mechanism fracture propagation. Finally, the most probable mechanism for bucket damage, conclusions and recommendations to prevent failures of the buckets are presented.
Effect on fatigue crack growth of interactions between overloads
Authors: POMMIER S. , DE FREITAS M. 
Published: March 2003

ABSTRACT Various types of interactions between overloads were studied in a 0.38% C low carbon steel. The retarding effect due to consecutive overloads is found to increase with the number of overloads, until it reaches a maximum. Similarly, it is found that a critical distance between overloads ensures the highest retarding effect, while shorter or longer spacing are less efficient for retarding crack growth. These effects are successfully explained using FEM calculations of the effective stress intensity factor. The kinematic hardening of the alloy, which is very efficient in ferritic–pearlitic steels, is shown to be mostly responsible for those effects. Taking into account the amplitude of kinematic hardening allows qualitative explanation of the observed effects. The order of application of the cycles during variable amplitude fatigue is thus important and should be taken into account for predicting fatigue lives.
Fatigue of clamped connections with application to a stem‐handlebar assembly for off‐road bicycles
Authors: McKENNA S. P. , HILL M. R. , HULL M. L. 
Published: March 2003

ABSTRACTThe objectives of this study were: (i) to determine the stresses as a result of assembly and the stress concentration of a clamped connection, (ii) to demonstrate the importance of the effects of assembly in fatigue life predictions and (iii) to verify the accuracy of fatigue life predictions by measuring fatigue life experimentally. A stem‐handlebar assembly used in off‐road bicycles was chosen for the study because it is a critical assembly for which structural reliability must be insured to prevent serious injury. Assembly stresses in the handlebar exceeded 200 MPa and stress concentration because of the attached stem increased the applied stress by 40%. A stress‐life prediction indicated that assembly effects would reduce predicted fatigue life of the handlebar by a factor of approximately 20. The measured fatigue lifetime of the handlebar was longer than that predicted by using the stress‐life approach, but was much shorter than that predicted when assembly effects were ignored. Therefore, assembly effects have a significant effect on fatigue life predictions and should be included in lifetime assessments for clamped mechanical assemblies.
Fretting fatigue crack initiation mechanism in Ti–6Al–4V
Authors: NAMJOSHI S. A. , MALL S. , JAIN V. K. , JIN O. 
Published: March 2003

ABSTRACTFretting fatigue crack initiation in titanium alloy, Ti−6Al−4V, was investigated experimentally and analytically by using finite element analysis (FEA). Various types of fretting pads were used in order to determine the effects of contact geometries. Crack initiation location and crack angle orientation along the contact surface were determined by using microscopy. Finite element analysis was used in order to obtain stress state for the experimental conditions used during fretting fatigue tests. These were then used in order to investigate several critical plane based multiaxial fatigue parameters. These parameters were evaluated based on their ability to predict crack initiation location, crack orientation angle along the contact surface and the number of cycles to fretting fatigue crack initiation independent of geometry of fretting pad. These predictions were compared with their experimental counterparts in order to characterize the role of normal and shear stresses on fretting fatigue crack initiation. From these comparisons, fretting fatigue crack initiation mechanism in the tested titanium alloy appears to be governed by shear stress on the critical plane. However, normal stress on the critical plane also seems to play a role in fretting fatigue life. At present, the individual contributions/importance of shear and normal stresses in the crack initiation appears to be unclear; however, it is clear that any critical plane describing fretting fatigue crack initiation behaviour independent of geometry needs to include components of both shear and normal stresses.
Micro‐fungi and invertebrate herbivores on birch trees: fungal mediated plant–herbivore interactions or responses to host quality?
Authors: Ahlholm Jouni , Helander Marjo , Elamo Pirjo , Saloniemi Irma , Neuvonen Seppo , Hanhimäki Sinikka , Saikkonen Kari 
Published: March 2003

AbstractWe studied interactions between microfungi and herbivores sharing a host tree. In a series of experiments and field observations over a 3‐year period, we compared phenotypic and genetic correlations of fungal frequencies and performance of invertebrate herbivores growing on mature half‐sib progenies of mountain birches (Betula pubescens ssp. czerepanovii) in two environments, a forested river valley and an adjacent higher‐elevation mountain birch woodland. We found little support for direct relation between fungal frequencies and performance of herbivore species. Instead, genetic correlations, particularly between autumnal moth (Epirrita autumnata) and rust fungus (Melampsoridium betulinum), suggest that herbivore performance may be caused by (1) genetic differences in plant quality for fungi and herbivores, or (2) genetic differences in responses to environmental conditions.
Temperature checks the Red Queen? Resistance and virulence in a fluctuating environment
Authors: Blanford Simon , Thomas Matthew B. , Pugh Clare , Pell Judy K. 
Published: March 2003

AbstractNumerous studies have revealed genetic variation in resistance and susceptibility in host–parasite interactions and therefore the potential for frequency‐dependent selection (Red Queen dynamics). Few studies, if any, have considered the abiotic environment as a mediating factor in these interactions. Using the pea aphid, Acyrthosiphon pisum, and its fungal pathogen, Erynia neoaphidis, as a model host–parasite system, we demonstrate how temperature can mediate the expression of genotypic variation for susceptibility and virulence. Whilst previous studies have revealed among‐clone variation in aphid resistance to this pathogen, we show that resistance rankings derived from assessments at one temperature, are not conserved across differing temperature regimes. We suggest that variation in environmental temperature, through its nonlinear impact on parasite virulence and host defence, may contribute to the general lack of evidence for frequency‐dependent selection in field systems.
How accurate are population models? Lessons from landscape‐scale tests in a fragmented system
Authors: Lindenmayer D. B. , Possingham H. P. , Lacy R. C. , McCarthy M. A. , Pope M. L. 
Published: March 2003

AbstractThere is a growing debate about the ability of Population Viability Analysis (PVA) to predict the risk of extinction. Previously, the debate has focused largely on models where spatial variation and species movement are ignored. We present a synthesis of the key results for an array of different species for which detailed tests of the accuracy of PVA models were completed. These models included spatial variation in habitat quality and the movement of individuals across a landscape. The models were good approximations for some species, but poor for others. Predictive ability was limited by complex processes typically overlooked in spatial population models, these being interactions between landscape structure and life history attributes. Accuracy of models could not be determined a priori, although model tests indicated how they might be improved. Importantly, model predictions were poor for some species that are among the best‐studied vertebrates in Australia. This indicated that although the availability of good life history data is a key part of PVA other factors also influence model accuracy. We were also able to draw broad conclusions about the sorts of populations and life history characteristics where model predictions are likely to be less accurate. Predictions of extinction risk are often essential for real‐world population management. Therefore, we believe that although PVA has been shown to be less than perfect, it remains a useful tool particularly in the absence of alternative approaches. Hence, tests of PVA models should be motivated by the cycle of testing and improvement.
Hungry bacteria – definition and properties of a nutritional state
Authors: Ferenci Thomas 
Published: March 2003

SummaryBacteria are sometimes neither starving nor under nutrient‐excess conditions. When growing with suboptimal levels of nutrients, hungry bacteria express appropriate cellular responses. This review discusses approaches to defining the hunger response in both molecular and growth kinetic terms. The gene expression changes unique to hunger conditions are described, using Escherichia coli as the primary example. Metabolite changes with hunger and starvation and the differing role of the stationary phase regulator RpoS also lead to the hypothesis proposed in this review that bacteria undertake distinct approaches to hunger and starvation. Indeed, an understanding of the difference between hunger and starvation and the incompatibility between hunger and starvation responses explains some of the paradoxical mutational adaptations, such as rpoS inactivation, found in natural populations.
Antibiotic resistance in bacteria from magpies (Pica pica) and rabbits (Oryctolagus cuniculus) from west Wales
Authors: Livermore David M. , Warner Marina , Hall Lucinda M. C. , Enne Virve I. , Projan Stephen J. , Dunman Paul M. , Wooster Sarah L. , Harrison Graham 
Published: March 2003

SummaryThe prevalence of antibiotic‐resistant bacteria in wild animal and bird populations is largely unknown, with little consistency among the few published reports. We therefore examined intestinal bacteria from magpies (Pica pica) and rabbits (Oryctolagus cuniculus) collected in rural west Wales. Escherichia coli isolates resistant to multiple antibiotics were grown from eight of 20 magpies trapped in spring, 1999 and one of 17 in spring, 2000; the most prevalent resistance trait among these isolates was to tetracycline, but resistances to ampicillin, chloramphenicol, kanamycin, sulphonamide, tetracycline and trimethoprim were also found. Tetracycline‐resistant Enterococcus spp. were found in one of 20 magpies in 1999 and three of 17 in 2000. Only one resistant E. coli isolate was detected among gut bacteria from 13 rabbits, and this strain was resistant only to tetracycline. Differences in the prevalence of resistance between bacteria from rabbits and magpies may reflect differences in diet: rabbits graze field edges, whereas magpies are omnivorous and opportunistic. The resistance genes found in E. coli isolates from magpies mostly corresponded to those common among human isolates, but those conferring tetracycline resistance were unique.
Prevalence and microdiversity of Alteromonas macleodii‐like microorganisms in different oceanic regions
Authors: García‐Martínez Jesús , Acinas Silvia G. , Massana Ramon , Rodríguez‐Valera Francisco 
Published: March 2003

SummaryThe presence, prevalence and variability of microorganisms related to the species Alteromonas macleodii, a well known culturable γ‐Proteobacterium, has been studied in different seawater samples from diverse geographical locations, in both the Northern and Southern hemispheres, and tested with two molecular techniques (rRNA hybridization and gene cloning and sequencing). Results show that A. macleodii‐like microorganisms are present in high proportions in North Atlantic and, especially, Mediterranean waters, being higher at deep samples and particle‐associated fractions, in agreement with previous findings. In contrast, Southern samples (all from very cold areas near Antarctica) presented no significant hybridization signals. The analysis of the ribosomal ITS (16S‐23S internal transcribed spacers) revealed that A. macleodii‐like microorganisms from Mediterranean, North Atlantic, Caribbean and Red Sea waters differed in both size and sequence, mostly depending on their geographical origin, with Mediterranean and North Atlantic clones clustering into two main groups whereas Caribbean and Red Sea clones appeared separated.