bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth in elevated CO2 enhances temperature response of photosynthesis in wheat
Authors: Alonso Aitor , Pérez Pilar , Martínez‐Carrasco Rafael
Published: October 2008

The temperature dependence of C3 photosynthesis may be altered by the growth environment. The effects of long‐term growth in elevated CO2 on photosynthesis temperature response have been investigated in wheat (Triticum aestivum L.) grown in controlled chambers with 370 or 700 μmol mol−1 CO2 from sowing through to anthesis. Gas exchange was measured in flag leaves at ear emergence, and the parameters of a biochemical photosynthesis model were determined along with their temperature responses. Elevated CO2 slightly decreased the CO2 compensation point and increased the rate of respiration in the light and ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco) Vcmax, although the latter effect was reversed at 15°C. With elevated CO2, Jmax decreased in the 15–25°C temperature range and increased at 30 and 35°C. The temperature response (activation energy) of Vcmax and Jmax increased with growth in elevated CO2. CO2 enrichment decreased the ribulose 1,5‐bisphosphate (RuBP)‐limited photosynthesis rates at lower temperatures and increased Rubisco‐ and RuBP‐limited rates at higher temperatures. The results show that the photosynthesis temperature response is enhanced by growth in elevated CO2. We conclude that if temperature acclimation and factors such as nutrients or water availability do not modify or negate this enhancement, the effects of future increases in air CO2 on photosynthetic electron transport and Rubisco kinetics may improve the photosynthetic response of wheat to global warming.
Micafungin alone or in combination with other systemic antifungal therapies in hematopoietic stem cell transplant recipients with invasive aspergillosis
Authors: Kontoyiannis D.P. , Ratanatharathorn V. , Young J.‐A. , Raymond J. , Laverdière M. , Denning D.W. , Patterson T.F. , Facklam D. , Kovanda L. , Arnold L. , Lau W. , Buell D. , Marr K.A.
Published: October 2008

Abstract: We describe herein 98 hematopoietic stem cell transplant (HSCT) recipients with invasive aspergillosis (IA) (refractory in 83) who received micafungin either alone (8 patients) or in combination with other licensed antifungal therapies (OLAT) (90 patients). Of the 8 monotherapy patients, 4 were failing OLAT, received de novo micafungin, or were intolerant to prior OLAT (2 patients each). Of the 90 patients treated with combination, 7 had de novo IA and 83 had refractory infection. Most patients (81) had pulmonary IA, 42 (43%) had graft‐versus‐host disease (GVHD), and 26 (27%) were neutropenic (absolute neutrophil count <500 cells/mm3) at onset of treatment. Successful response was seen in 25/98 (26%); an additional 12 patients achieved stable disease. Response was seen in 2/9 (22%) in de novo treatment, 21/87 (24%) in refractory patients, and 2/2 (100%) in toxicity failure patients. Additionally, response was seen in 22 of the 90 (24%) patients treated with combination therapy, and in 3 of 8 (38%) patients who were treated with micafungin alone. No significant differences in responses were found based on type of HSCT, GVHD status, site of IA, or Aspergillus species, and no significant toxicity was seen. Micafungin was well tolerated, even at high doses, and is a reasonable option for treatment of IA in this high‐risk patient population.
Strongyloides stercoralis hyperinfection syndrome after liver transplantation: case report and literature review
Authors: Vilela E.G. , Clemente W.T. , Mira R.R.L. , Torres H.O.G. , Veloso L.F. , Fonseca L.P. , De Carvalho e Fonseca L.R. , Franca M.d.C. , Lima A.S.
Published: October 2008

Abstract: Strongyloides stercoralis is an intestinal nematode that causes human infections and whose life cycle has special features, including autoinfection. Strongyloides infection may be asymptomatic for years, owing to a low parasite load. During immunosuppressive therapy, however, if cellular immunity is depressed, autoinfection can occur at a higher rate, resulting in hyperinfection syndrome. In this specific circumstance, it can become a fatal illness. We describe a case of hyperinfection syndrome in a liver transplant recipient and also review the literature.
Mycobacterium chelonae necrotizing pneumonia after allogeneic hematopoietic stem cell transplant: report of clinical response to treatment with tigecycline
Authors: Peres E. , Khaled Y. , Krijanovski O.I. , Mineishi S. , Levine J.E. , Kaul D.R. , Riddell J.
Published: October 2008

Abstract: We present a case of progressive Mycobacterium chelonae ssp. chelonae necrotizing pneumonia after hematopoietic stem cell transplantation (HSCT) in the presence of chronic graft‐versus‐host disease. The patient failed to respond to standard combination therapy with multiple agents and developed resistance to most drugs over the course of treatment. Tigecycline, a new glycylcycline antimicrobial agent with in vitro activity against M. chelonae, was then used with a clinical response to treatment. To our knowledge, this is the first reported case demonstrating tigecycline to have a degree of clinical effectiveness to treat refractory pulmonary infection with M. chelonae in an HSCT recipient.
Effect of Arbuscular Mycorrhization on the Accumulation of Hydroxycinnamic Acid Derivatives in Date Palm Seedlings Challenged with Fusarium oxysporum f. sp. albedinis
Authors: Jaiti Fatima , Kassami Mouna , Meddich Abdelillah , El Hadrami Ismail
Published: October 2008

The effect of root colonization with arbuscular mycorrhizal fungi on the content of phenolic compounds was determined in date palm seedlings challenged with Fusarium oxysporum f. sp. albedinis (Foa), the pathogen causing the bayoud disease. The examination of phenolic compounds revealed no qualitative difference between arbuscular mycorrhized plants and non‐mycorrhized ones. However, after Foa infection, the accumulation of non‐constitutive hydroxycinnamic acid derivatives, such as the sinapic derivative I2, known to play a crucial role in resistance of date palm to Foa was more pronounced in mycorrhized seedlings. No accumulation of these compounds was detected in mycorrhized seedlings not challenged with Foa. The potential immunization of date palm seedlings with mycorrhizal fungi is discussed.
CHANGES IN PLATELET SIZE AND SPLEEN VOLUME IN RESPONSE TO SELECTIVE AND NON‐SELECTIVE β‐ADRENOCEPTOR BLOCKADE IN HYPERTENSIVE PATIENTS
Authors: Bakovic Darija , Pivac Nediljko , Eterovic Davor , Palada Ivan , Valic Zoran , Paukovic‐Sekulic Branka , Dujic Zeljko
Published: October 2008

The spleen contains approximately one‐third of all the body's platelets. These platelets are relatively larger and haemostatically more active than platelets in the systemic circulation and can be released into the systemic circulation by stimulation of α‐adrenoceptors or inhibition of β‐adrenoceptors. In the present study, we evaluated the effects of selective (bisoprol) and non‐selective (carvedilol) beta‐blockers agents on mean platelet volume (MPV) and spleen size in hypertensive patients at rest and after exercise.

Blood pressure, heart rate, platelet count, MPV and spleen volume were measured in 18 newly diagnosed hypertensive patients, as well as in nine healthy control subjects, subjected to treadmill exercise test at their first visit and, for the hypertensive group, after 15 and 30 days of treatment with the selective β1‐adrenoceptor antagonist bisoprolol 5 mg/day (n = 9) or the non‐selective α1‐, β1‐ and β2‐adrenoceptor antagonist carvedilol 25 mg/day (n = 9).

Increases in resting MPV values with concomitant decreases in spleen volume were found after 15 and 30 days treatment with either bisoprolol or carvedilol. The pronounced decrease in splenic volume after exercise and the increased MPV and platelet counts seen at first visit were halved after 15 and 30 days of treatment with either drug.

We conclude that in hypertensive patients treated with either selective or non‐selective beta‐blockers, the spleen contracts and MPV increases, which may increase the risk of atherothrombosis.
CONTROL OF MUSCLE RYANODINE RECEPTOR CALCIUM RELEASE CHANNELS BY PROTEINS IN THE SARCOPLASMIC RETICULUM LUMEN
Authors: Beard Nicole A , Wei Lan , Dulhunty Angela F
Published: October 2008

Many biological processes that are governed by intracellular calcium signals rely on intracellular stores, which provide a reliable, controlled release of calcium into the cytoplasm. Calcium release through the ryanodine receptor (RyR), the main ion channel in the sarcoplasmic reticulum (the calcium store in muscle) is the key determinant of muscle force.

Calsequestrin, the main calcium buffer in the sarcoplasmic reticulum, provides a pool of calcium for release through the RyR and acts as a luminal calcium sensor for the channel via its interactions with triadin and junctin. Until recently, how calsequestrin communicated the store Ca2+ load to the RyR remained unknown.

Calsequestrin 1 (skeletal calsequestrin) has been shown to both inhibit and activate the skeletal RyR1, dependent on whether it's bound to the RyR1 directly or indirectly via anchoring proteins.

The phosphorylation status of calsequestrin 1 is deemed important: it influences the Ca2+ binding capacity of calsequestrin, the way in which calsequestrin 1 regulates the RyR1 and how calsequestrin 1 interacts with the key anchoring protein junctin.

In skeletal muscle, junctin plays a more critical role than triadin in the mechanism that controls Ca2+ release from the sarcoplasmic reticulum.

The close relationship between altered expression and dysfunction of calsequestrin in several skeletal and cardiac disorders highlights the critical role that calsequestrin plays in maintaining Ca2+ homeostasis and regulation of muscle contraction.
STORE‐OPERATED Ca2+ CHANNELS AND MICRODOMAINS OF Ca2+ IN LIVER CELLS
Authors: Barritt Greg J , Litjens Tom L , Castro Joel , Aromataris Edoardo , Rychkov Grigori Y
Published: October 2008

Oscillatory increases in the cytoplasmic Ca2+ concentration ([Ca2+]cyt) play essential roles in the hormonal regulation of liver cells. Increases in [Ca2+]cyt require Ca2+ release from the endoplasmic reticulum (ER) and Ca2+ entry across the plasma membrane.

Store‐operated Ca2+ channels (SOCs), activated by a decrease in Ca2+ in the ER lumen, are responsible for maintaining adequate ER Ca2+. Experiments using patch‐clamp recording and the fluorescent Ca2+ reporter fura‐2 indicate there is only one type of SOC in rat liver cells. These SOCs have a high selectivity for Ca2+ and properties essentially indistinguishable from those of Ca2+ release‐activated Ca2+ (CRAC) channels.

Although Orai1, a CRAC channel pore protein, and stromal interaction molecule 1 (STIM1), a CRAC channel Ca2+ sensor, are components of liver cell SOCs, the mechanism of activation of SOCs, and in particular the role of subregions of the ER, are not well understood.

Recent experiments have used the transient receptor potential vanilloid 1 (TRPV1) non‐selective cation channel, ectopically expressed in liver cells, and a choleretic bile acid to deplete Ca2+ from different ER subregions. The results of these studies have provided evidence that only a small component of the ER is required for STIM1 redistribution and the activation of SOCs.

It is concluded that different Ca2+ microdomains in the ER and cytoplasmic space are important in both the activation of SOCs and in the signalling actions of Ca2+ in liver cells. Future experiments will investigate the nature of these microdomains further.
A native dasyurid predator (common planigale, Planigale maculata) rapidly learns to avoid a toxic invader
Authors: WEBB JONATHAN K. , BROWN GREGORY P. , CHILD TRAVIS , GREENLEES MATTHEW J. , PHILLIPS BENJAMIN L. , SHINE RICHARD
Published: October 2008

Abstract  Interactions between invasive species and native fauna afford a unique opportunity to examine interspecific encounters as they first occur, without the complications introduced by coevolution. In northern Australia, the continuing invasion of the highly toxic cane toad Bufo marinus poses a threat to many frog‐eating predators. Can predators learn to distinguish the novel toxic prey item from native prey (and thus, avoid being poisoned), or are longer‐term genetically based changes to attack behaviour needed before predators can coexist with toads? To predict the short‐term impact of cane toads on native predators, we need to know the proportion of individuals that will attack toads, the proportion surviving the encounter, and whether surviving predators learn to avoid toads. We quantified these traits in a dasyurid (common planigale, Planigale maculata) that inhabits tropical floodplains across northern Australia. Although 90% of naïve planigales attacked cane toads, 83% of these animals survived because they either rejected the toad unharmed, or killed and consumed the prey snout‐first (thereby avoiding the toxin‐laden parotoid glands). Most planigales showed one‐trial learning and subsequently refused to attack cane toads for long time periods (up to 28 days). Toad‐exposed planigales also avoided native frogs for up to 9 days, thereby providing an immediate benefit to native anurans. However, the predators gradually learnt to use chemical cues to discriminate between frogs and toads. Collectively, our results suggest that generalist predators can learn to distinguish and avoid novel toxic prey very rapidly – and hence, that small dasyurid predators can rapidly adapt to the cane toad invasion. Indeed, it may be feasible to teach especially vulnerable predators to avoid cane toads before the toads invade, by deploying low‐toxicity baits that stimulate taste‐aversion learning.
Fire resilience of ant assemblages in long‐unburnt savanna of northern Australia
Authors: PARR CATHERINE L. , ANDERSEN ALAN N.
Published: October 2008

Abstract  Tropical savannas and rainforests contrast in their flammability and the fire resilience of their associated species. While savanna species generally exhibit high resilience to burning, there is much debate about the fire resilience of forest‐associated species, and the persistence of forest patches in a flammable savanna matrix. Where fire has been excluded, savanna tends on a trajectory towards forest, with an increase in forest‐associated plants and animal species. This study tested the idea that given the high proportion of forest‐associated taxa in long‐unburnt savanna, the fauna of these areas would be expected to exhibit less resilience to fire than the fauna in frequently burnt savannas. The study investigated the immediate and short‐term effects on ant assemblages of re‐introducing fire into long‐unburnt savanna in northern Australia. The ant fauna exhibited high resistance to fires, with no significant short‐term change in mean abundance or species richness; instead, seasonality had a far stronger influence on overall ant activity. Fire caused dramatic declines in dominance of the patchily distributed forest‐associated species Oecophylla smaragdina and Papyrius sp., but had no effect on overall dominance by open savanna species of Iridomyrmex. Dominance by Iridomyrmex pallidus declined, but this was compensated for by increases in I. reburrus, while two other species of Iridomyrmex showed no change. This indicates a high level of functional redundancy among dominant species of Iridomyrmex, which universally dominate open savanna communities, but not of dominant forest‐associated species. Overall, our findings demonstrate a high degree of fire‐resilience of the long‐unburnt savanna ant fauna. Despite the occurrence of forest‐associated species, the high proportion of savanna species persisting in this habitat means that long‐unburnt savanna retains the general response characteristics of frequently burnt savanna.
Population ecology of the velvet gecko, Oedura lesueurii in south eastern Australia: Implications for the persistence of an endangered snake
Authors: WEBB JONATHAN K. , PIKE DAVID A. , SHINE RICHARD
Published: October 2008

Abstract  Ecological specialization, such as major dependence upon a single‐prey species, can render a predator taxon vulnerable to extinction. In such cases, understanding the population dynamics of that prey type is important for conserving the predator that relies upon it. In eastern Australia, the endangered broad‐headed snake Hoplocephalus bungaroides feeds largely on velvet geckos (Oedura lesueurii). We studied growth, longevity and reproduction in a population of velvet geckos in Morton National Park in south‐eastern Australia. We marked 458 individual geckos over a 3‐year period (1992–1995) and made yearly visits to field sites from 1995–2006 to recapture marked individuals. Female geckos grew larger than males, and produced their first clutch at age 4 years. Males can mature at 2 years, but male–male combat for females probably forces males to delay reproduction until age 3 years. Females lay a single clutch of two eggs in communal nests in November, and up to 22 females deposited eggs in a single nest. Egg hatching success was high (100%), and juveniles had high survival (76%) during their first 6 months of life. Velvet geckos are long‐lived, and the mean age of marked animals recaptured after 1995 was 6.1 years (males) and 8.4 years (females). Older females (7.5–9.5 years) were all gravid when last recaptured. Like other temperate‐climate gekkonids, O. lesueurii has a ‘slow’ life history, and population viability could be threatened by any factors that increase egg or adult mortality. Two such factors – the removal of ‘bush rocks’ for urban gardens, and the overgrowth of rock outcrops by vegetation – could render small gecko populations vulnerable to extinction. In turn, the reliance of predatory broad‐headed snakes on this slow‐growing lizard species may increase its vulnerability to extinction.
Variegated desert vegetation: Covariation of edaphic and fire variables provides a framework for understanding mulga‐spinifex coexistence
Authors: NANO CATHERINE E. M. , CLARKE PETER J.
Published: October 2008

Abstract  Mulga (Acacia aneura Mimosaceae) and spinifex (Triodia spp. Poaceae) habitats together characterize a large part of arid central Australia. Often very abrupt boundaries form between these two habitats, giving rise to a mosaic pattern of contrasting shrub‐grass alterations across the landscape. Reasons for such patterning remain poorly understood though current niche‐based views relate species' distributions to spatial resource gradients or to fire effects. Field survey work was conducted on central Australian mountain ranges to further quantify floristic, regeneration traits, and structural patterning across mulga‐spinifex transitions and to test resource‐ and disturbance‐models that explain these patterns. Compositional analysis demonstrated variability in transition type – in certain cases boundaries denoted true floristic discontinuity and in others, somewhat more of a structural shift. Moreover, it was shown that minimal between‐habitat floristic overlap coincided with the occurrence of distinct edaphic changes, while greater compositional commonality occurred when soil gradients were more diffuse. This indicated that floristic patterning cannot be ascribed to any one single process. In the case of strong soil gradients, between‐habitat segregation most likely resulted from resource‐based niche differentiation; for weaker gradients, fire‐frequency assumed greatest importance. Disturbance theory most readily accounted for the distribution of woody species' post‐fire regeneration traits across habitat boundaries. The results also suggested that biotic factors –viz competition, facilitation and animal‐mediated dispersal – may be of additional consequence for mulga‐spinifex coexistence. Overall, the study served to emphasize the importance of multi‐factor explanation for within‐ and between‐habitat patterning in these mosaics. It also highlighted the need for experimentation to facilitate distinction between cause and correlation.
Is decline in high altitude eucalypt forests related to rainforest understorey development and altered soil bacteria following the long absence of fire?
Authors: HARVEST T. , DAVIDSON N. J. , CLOSE D. C.
Published: October 2008

Abstract  The objective of this study was to identify attributes of the understorey vegetation, soil root biomass, soil chemistry and microbial community that may be associated with tree decline in high altitude eucalypt forests in Tasmania. The sites studied were in healthy eucalypt forest, forest in decline and forest containing dead eucalypts dominated by rainforest, in north‐east (Eucalyptus delegatensis forest) and in north‐west (Eucalyptus coccifera forest) Tasmania. In both regions bare ground, rock and shrubby species were associated with healthy sites whereas decline sites were associated with moss and a tall understorey with a high percentage cover of rainforest species. Healthy sites had low root biomass in the top 10 cm of the soil profile relative to decline and rainforest sites. Seedlings of high altitude species were grown in rainforest soil (0.314% N and 0.060% P) and healthy eucalypt soil (0.253% N and 0.018% P). The four eucalypt species studied had similar root to shoot ratio in the two soils, but the rainforest species, Nothofagus cunninghamii and Leptospermum lanigerum, had higher root to shoot ratio in the healthy eucalypt than in the rainforest soil. We produced three soil filtrates: (i) fungi and bacteria present; (ii) bacteria only present and; and (iii) sterile, from healthy, decline and rainforest sites in north‐east and in north‐west Tasmania and used linseed as a germination bioassay. Filtrates from the north‐east decline and rainforest sites induced a significantly greater dysplastic germination response than healthy sites in (i) and (ii) filtrates, but this was not found in filtrates from sites in the north‐west. We conclude that while the development of a rainforest understorey and elevated soil root biomass in the long absence of fire is generally associated with high altitude eucalypt decline, altered bacterial and/or chemical attributes of soil are not always associated with high altitude eucalypt decline.
Effects of leaf emergence on leaf lifespan are independent of life form and successional status
Authors: DUNGAN ROGER J. , NAVAS MARIE‐LAURE , DUNCAN RICHARD P. , GARNIER ERIC
Published: October 2008

Abstract  The longevity of a leaf is related to the benefit that the plant is able to derive from it. This benefit varies among seasons and as more leaves emerge, such that leaf lifespan can be limited by canopy position rather than physiological age. Using interval‐censored failure time analysis, we investigate leaf lifespan for 34 Mediterranean species in a previously published dataset involving species with different life forms and functional strategies. Failure time regression models were used to determine leaf lifespan, and to investigate how these effects varied among species. Median lifespan estimated for each species with two methods differed by less than 10% on average, but varied from 0.02–19.5% depending on the shape of the underlying failure time distribution. Within shoots, later‐emerging leaves had shorter lifespans for species with longer periods of leaf emergence, and the reverse was true for species with short emergence. Having accounted for the within‐shoot effect, leaves emerging in spring had shorter lifespans, particularly herbaceous species, whereas the reverse was true woody species. These effects were consistent among life forms and successional stages, and consistent with theories of within‐shoot translocation of resources following self‐shading.
Phenological patterns of neotropical lotic chironomids: Is emergence constrained by environmental factors?
Authors: SIQUEIRA TADEU , DE OLIVEIRA ROQUE FABIO , TRIVINHO‐STRIXINO SUSANA
Published: October 2008

Abstract  In this paper we analyzed the emergence phenology of a highly diverse chironomid assemblage to test for association between emergence and some environmental variables and for the presence of synchrony in emergence. We used a time series of 48 weekly samples from a tropical low order forested stream (south‐eastern Brazil) to describe how this assemblage varied in an intra‐annual scale. An eigenvector‐based filtering approach was adapted to create temporal variables that could be used in our multiple regression analyses, trying to overcome the problems of temporal autocorrelation. Emergence of the Chironomidae, two subfamilies, concordant species, and of dominant species was not related to rainfall, temperature, moon phase or photoperiod. Taxonomic composition and species richness did not change across time. The number of emerging individuals of the subfamily Orthocladiinae was significantly related to temperature and to temporal filters. The inclusion of the temporal filters into the analyses almost eliminated autocorrelation in the regression residuals. We detected interspecific synchrony in a group of species, but an absence of trends and periodicity in chironomid emergence, which was not related to environmental variables. This suggests that unknown factors, differing from those known to control emergence in temperate regions, operate in the tropics. The erratic behaviour of the analyzed series raises the question of whether chaotic dynamics may generate this variability.
Thirsty sea snakes forsake refuge during rainfall
Authors: BONNET XAVIER , BRISCHOUX FRANÇOIS
Published: October 2008

Abstract  Vertebrates living in dry or salty habitats spend significant amounts of time and energy maintaining their hydro‐mineral balance; any opportunity to drink fresh water should reduce such expenses. However, to find fresh water, individuals are generally forced to leave the safe and buffered conditions that prevail in their refuges. Therefore, they must face harsh environmental conditions and increased predation risks. We examined this trade‐off in the field, using a very large dataset gathered on amphibious sea snakes that confront periodic droughts. The study was carried out on different islets in the lagoon of New Caledonia. As expected, sea kraits remain concealed most of the time under rocks or within burrows during dry weather. They select precise time windows to move rapidly between the sea and the land, thereby minimizing the time spent in the open. Rainfall triggered massive disruptions of this rhythm: many snakes quickly forsook their shelter to drink in the open, and remained almost motionless until satiety. Interestingly, they adopted specific and unusual postures to drink. They perched on the top of rocks that were benefiting from running and less salty water during downpours. They also drank the droplets attached to vegetation during drizzle.
MILITARY STATIC LINE PARACHUTE INJURIES IN AN AUSTRALIAN COMMANDO BATTALION
Authors: Hughes Craig D. , Weinrauch Patrick C. L.
Published: October 2008

Background:  The objective of this study was to define the casualty rates and anatomical distribution of injuries associated with military static line parachute (MSLP) descents conducted by an Australian Army Commando Battalion. This study was conducted to identify the strategies to reduce the injury burden related to MSLP activities.

Method:  A retrospective audit of injuries resulting from MSLP descents conducted by 4th Battalion Royal Australian Regiment (4 RAR) over a 13‐month period.

Results:  A total of 554 MSLP descents over the time period were reviewed. The overall casualty rate was 5.1%. For MSLP descents onto land drop zones, the incidence of injury requiring hospital admission was 2.6%. Paratrooper bodyweight was associated with increased risk of injury (P = 0.04) and hospital admission (P = 0.003), particularly when conducting descents onto land drop zones. MSLP descents conducted onto land were associated with a higher incidence of casualties when compared with those conducted into water drop zones (P = 0.001).

Conclusion:  During the period from February 2004 until February 2005, 4 RAR (Commando) experienced higher casualty rates during MSLP descents than expected when compared with the published report. Strategies to decrease the casualty rate of MSLP descents onto land drop zones may include more extensive ground training, increased frequency of MSLP descents, use of ankle braces and the development of purpose built drop zones. Consideration should be given to establishing a maximum bodyweight threshold for the conduct of MSLP activities or acquiring parachutes with decreased descent velocity for larger paratroopers.
AUSTRALIAN AND NEW ZEALAND STUDY COMPARING LAPAROSCOPIC AND OPEN SURGERIES FOR COLON CANCER IN ADULTS: ORGANIZATION AND CONDUCT†
Authors: Allardyce Randall A. , Bagshaw Philip F. , Frampton Christopher M. , Frizelle Francis A. , Hewett Peter J. , Rieger Nicholas A. , Smith Shona , Solomon Michael J. , Stevenson Andrew R. L.
Published: October 2008

This article describes the initiation and implementation of the multicentre Australia and New Zealand prospective randomized controlled clinical study comparing laparoscopic and conventional open surgical treatments of right‐sided and left‐sided potentially curable colon cancer (Australasian Laparoscopic Colon Cancer Study). Six hundred and one adult patients were admitted with a clinical diagnosis of a single adenocarcinoma based on a physical examination and colonoscopy, barium enema or computed tomography scan and randomly allocated to either laparoscopic or open surgery. The primary aim of the study is to compare 5‐year mortality and tumour recurrence rates between the two groups. Secondary aims include comparisons of safety (intraoperative and early postoperative complications, wound site recurrence, postoperative recovery and 30‐day mortality), quality of life, in‐hospital costs and short‐term mortality and tumour recurrence. The data for 592 patients have been collected. There are currently 3141 person years of follow up. In all 370 patients have been assessed at 5 years. This study shows that large cooperative Australia–New Zealand surgical trials can and should be carried out to address significant clinical issues. When possible, coherence with similar, concurrent international trial protocols ensures broader analyses and applicability of results. It is important to recognize that special attention to sustained funding, surgeon credentialing, clinical protocol standardization, data management, publication policy and the protection of study credibility is required from the outset. The Australasian Laparoscopic Colon Cancer Study will achieve its aims with 5‐year assessments of all entered patients in March 2010.
ASERNIP‐S: INTERNATIONAL TREND SETTING
Authors: Maddern Guy , Boult Margaret , Ahern Eleanor , Babidge Wendy
Published: October 2008

The Australian Safety and Efficacy Register of New Interventional Procedures – Surgical (ASERNIP‐S) came into being 10 years ago to provide health technology assessments specifically tailored towards new surgical techniques and technologies. It was and remains the only organisation in the world to focus on this area of research. Most funding has been provided by the Australian Government Department of Health, and assessments have helped inform the introduction of new surgical techniques into Australia. ASERNIP‐S is a project of the Royal Australasian College of Surgeons. The ASERNIP‐S program employs a diverse range of methods including systematic reviews, technology overviews, assessments of new and emerging surgical technologies identified by horizon scanning, and audit. Support and guidance for the program is provided by Fellows of the Royal Australasian College of Surgeons. ASERNIP‐S works closely with consumers to produce health technology assessments and audits, as well as consumer information to keep patients fully informed of research. Since its inception, the ASERNIP‐S program has developed a strong international profile through the production of over 60 reports on evidence‐based surgery, surgical technologies and audit. The work undertaken by ASERNIP‐S has evolved from assessments of the safety and efficacy of procedures to include guidance on policies and surgical training programs. ASERNIP‐S needs to secure funding so that it can continue to play an integral role in the improvement of quality of care both in Australia and internationally.
FEASIBILITY STUDY OF DAY CASE THYROIDECTOMY
Authors: Teoh Anthony Y. B. , Tang Y. C. , Leong H. T.
Published: October 2008

Introduction:  The aim of this retrospective study was to assess the feasibility and outcome of day case thyroidectomy in an ambulatory surgery centre in Hong Kong.

Methods:  Patients with day case thyroidectomy carried out between July 2005 and December 2006 were retrospectively reviewed. Day surgery was offered to patients satisfying the selection criteria for day case and having from benign unilobular thyroid disease.

Results:  Fifty patients had hemithyroidectomy carried out during the study period. There were 6 men and 44 women and the mean (standard deviation SD) age was 45.6 years (7.4 years). All patients were American Society for Anesthesiologists grade I (76%) or II (34%). The mean (SD) operative time was 79.5 min (17 min). Twelve patients had episodes of postoperative nausea and vomiting. The mean (SD) analgesic requirement was 0.7 tablets (0.5 tablets) of combination acetaminophen and phenyltoloxamine citrate before discharge. The mean (SD) time to discharge was 7.5 h (0.7 h). The overall discharge rate was 98% and the complication rate was 8%. One patient was observed overnight because of postoperative haematoma. One patient had recurrent laryngeal nerve injury. There were no unplanned readmissions postoperatively. Three patients had unsuspected thyroid malignancy on histopathology.

Conclusion:  This study showed the feasibility and safety of day case thyroidectomy. The setting was not associated with any increase in morbidity or mortality and has the potential in reducing hospital costs.
PATIENT KNOWLEDGE OF THE RISKS OF POST‐SPLENECTOMY SEPSIS
Authors: Wilkes Anna , Wills Vanessa , Smith Stephen
Published: October 2008

Background:  Splenectomy is associated with a lifelong increase in the risk of sepsis. The aim of this study was to determine the level of knowledge of patients who have undergone splenectomy within an Australian area health service.

Methods:  Adults undergoing a splenectomy between 1994 and 2004 within the Hunter Area Health Service were invited to participate in the study. Consenting participants were contacted by telephone and a standardized questionnaire completed.

Results:  More than 50% of participants displayed a good active knowledge of the risk of infection post‐splenectomy and an understanding of the role of vaccinations in reducing the risk of infection. Few participants (11.3%) had standby antibiotics readily available. Knowledge of travel precautions and risk of sepsis following animal bites was poor.

Conclusion:  Although most participants displayed a good knowledge of infection risk post‐splenectomy, deficiencies in knowledge were identified. We propose the development of a splenectomy protocol and patient briefing to improve patient education.
COMPARISON OF VOLUME DISPLACEMENT VERSUS CIRCUMFERENTIAL ARM MEASUREMENTS FOR LYMPHOEDEMA: IMPLICATIONS FOR THE SNAC TRIAL
Authors: Tewari Nilajana , Gill Peter G. , Bochner Melissa A. , Kollias James
Published: October 2008

Background:  The Royal Australasian College of Surgeons Sentinel Node versus Axillary Clearance trial is a randomized controlled trial comparing sentinel node biopsy with axillary clearance in breast cancer patients. Primary study end‐points include arm volume differences with time, which may indicate the development of lymphoedema. The RACS SNAC trial uses circumferential arm measurements in the estimation of arm volume. This study aimed to assess the accuracy of circumferential volume estimation in comparison with water displacement.

Methods:  Eighty‐seven women attending the breast clinic at the Women’s Health Centre, Royal Adelaide Hospital, were assessed by volumetric and circumferential arm measurements. Correlations between volume estimations and measurements were made, taking into account the width of measuring tape and body mass index.

Results:  There was a highly significant correlation between circumferential and volumetric arm measurements (Pearson’s correlation coefficient = 0.92, P < 0.0001), especially when using the narrow measuring tape. Correlation was best in the overweight BMI group (Pearson’s correlation coefficient = 0.94. P < 0.0001) and worst in the obese group (Pearson’s correlation coefficient = 0.79, P < 0.0001) but all relationships were statistically significant.

Conclusion:  Using a narrow tape, circumferential arm measurement is an appropriate method for assessing arm volume in the SNAC trial.
LAPAROSCOPIC ePTFE MESH REPAIR OF INCISIONAL AND VENTRAL HERNIAS
Authors: Gananadha Sivakumar , Samra Jaswinder S. , Smith Garett S. , Smith Ross C. , Leibman Steven , Hugh Thomas J.
Published: October 2008

Incisional hernia is a relatively frequent complication of abdominal surgery. The use of mesh to repair incisional and ventral hernias results in lower recurrence rates compared with primary suture techniques. The laparoscopic approach may be associated with lower postoperative morbidity compared with open procedures. Long‐term recurrence rates after laparoscopic ventral and incisional hernias are not well defined. A prospective study of the initial experience of a standardized technique of laparoscopic incisional and ventral hernia repair carried out in a tertiary referral hospital was undertaken between January 2003 and February 2007. Laparoscopic hernia repair was attempted in 71 patients and was successful in 68 (conversion rate 4%). The mean age of the patients identified was 63.1 years (39 men and 31 women). Multiple hernial defects were identified in 38 patients (56%), and the mean overall size of the fascial defects was 166 cm2. The mean mesh size used was 403 cm2. The mean operative time was 121 minutes. There were six (9%) major complications in this series, but there were no deaths. Hernia recurrence was noted in four patients (6%) at a mean follow up of 20 months. Our preliminary experience indicates that laparoscopic incisional and ventral hernia repair is technically feasible and has acceptable postoperative morbidity and low early recurrence rates.
Structural health monitoring using electro‐mechanical impedance sensors
Authors: PARK S. , YUN C.‐B. , INMAN D. J.
Published: October 2008

This paper reports recent achievements of novel structural health monitoring (SHM) techniques for damage diagnosis for critical members of civil, mechanical and aerospace structures using electro‐mechanical impedance sensors. The basic concept of this technique is to use simultaneously both high‐frequency structural excitations and responses employing piezoelectric sensors to monitor the local area of a structure for changes in structural impedance that would indicate imminent damage. In this paper, several principal software and hardware issues on these topics are described. A new impedance model is proposed that incorporates the effects of sensor and bonding defects for sensor self‐diagnosis. Temperature effects‐free impedance‐based damage detection algorithm using effective frequency shifts based on cross‐correlation coefficients is presented. In a sense of tailoring wireless sensing technology to the impedance methods, an active sensor node incorporating a miniaturized impedance sensing device, an on‐board microcontroller, and a radio frequency (RF) telemetry is introduced. A data compression algorithm is embedded into the on‐board chip of the active sensor node to enhance its local data processing‐capability. Finally, this paper concludes with a discussion of further studies and future applications.
Analytical study of piezoelectric paint sensor for acoustic emission‐based fracture monitoring
Authors: LI X. , ZHANG Y.
Published: October 2008

Analytical study of piezoelectric paint, which provides insight about its key material behaviour in ultrasonic sensing, is the focus of this paper. Piezoelectric paint is a composite piezoelectric material that comprises tiny piezoelectric particles randomly dispersed within a polymer matrix phase. Acoustic emission (AE) technique has been used for non‐destructive evaluation (NDE) such as fracture monitoring in metal, concrete and composite structures. The feasibility of using piezoelectric paint for AE sensing has been demonstrated. In the context of piezoelectric paint‐based AE sensor, models for the key material properties of piezoelectric paint are reviewed first. The effect of piezoelectric ceramic volume fraction on paint sensor response is examined. A coupled field finite element model was established to carry out the electro‐mechanical analysis of piezoelectric paint sensor subjected to AE excitation. The simulation model for piezoelectric paint sensor is calibrated with experimental data. While more extensive research needs to be done to characterize piezoelectric paint sensor for fracture monitoring, such an analytical study proves to be very useful to the optimization of piezoelectric paint formulation and sensor geometry for AE sensor.
Damage detection in an aluminium plate using outlier analysis
Authors: CHETWYND D. , RONGONG J. A. , PIERCE S. G. , WORDEN K.
Published: October 2008

This work presents a damage detection study of a curved aluminium panel using the statistical technique of outlier analysis, where the structure was investigated using ultrasonic Lamb waves. These waves were generated by large custom‐made piezoceramic patches and were sensed by smaller piezoceramic sensors surrounding each patch. The patches were mounted using the viscoelastic material Araldite 2027 and damage was added to the plate in the form of drilled holes and saw cuts increasing in length. Outlier analysis was successfully able to distinguish between the damaged and undamaged cases with a very high classification rate of over 99%, and was also able to approximate the direction from the actuator patch in which the damage lay.
Comparative study of nonlinear acoustic and Lamb wave techniques for fatigue crack detection in metallic structures
Authors: RYLES M. , NGAU F. H. , MCDONALD I. , STASZEWSKI W. J.
Published: October 2008

The paper deals with fatigue crack detection in metallic structures. A simple fatigue experiment is performed to initiate and propagate a crack in an aluminium plate. The plate is instrumented with two low‐profile piezoceramic transducers and one low‐profile piezoceramic stack actuator. Nonlinear acoustics and Lamb waves are used for crack detection. The former utilizes the high‐frequency acoustical wave and low‐frequency modal excitation for damage detection. Modulations sidebands around the acoustical spectral component are used to detect the crack. The latter produces Lamb wave responses that are de‐correlated due to the presence of the crack. Both effects are due to growing fatigue crack. Two simple signal parameters, namely the intensity of modulation and the normalized cross‐correlation coefficient are used as damage indicators. The study demonstrates similar sensitivity of both methods to small fatigue cracks.
Continuous fatigue crack monitoring without baseline data
Authors: KIM S. B. , SOHN H.
Published: October 2008

In order to overcome the susceptibility of conventional non‐destructive testing (NDT) techniques to operational and environmental variations, a new damage detection technique that does not require direct comparison with baseline data was previously developed by the authors for detecting a crack in a plate structure. This reference‐free technique employs two pairs of collocated lead zirconate titanate transducers (PZTs) placed on both sides of the plate to generate and measure Lamb waves. Then, the existence of mode conversion due to the crack is identified from the Lamb wave signals instantly measured by PZTs. In this study, the effectiveness of the proposed technique is tested using a steel girder specimen. A cyclic loading is applied to the girder resulting in fatigue cracks, and the proposed technique detects the appearance of fatigue damage solely based on the measured Lamb waves at the present stage. Experimental results are presented to demonstrate the applicability of the proposed technique to fatigue crack monitoring, and issues related to PZT installation are discussed.
A parametric study on fatigue strength of spot‐weld joints
Authors: ERTAS AHMET H. , SONMEZ FAZIL O.
Published: October 2008

Fastening elements usually lead to high stress concentrations; fatigue failure thus becomes the most critical failure mode for a fastening element itself or the region around it under fluctuating stresses. A designer should seek the ways of increasing fatigue strength of a joint to ensure the safety of the whole structure.

Resistance spot welding is the most preferred method to join metal sheets. The design variables for spot‐weld joints affecting their strengths are basically sheet thickness, spot‐weld nugget diameter, number of spot welds and the joint type as exemplified in tensile shear (TS), modified tensile shear (MTS), coach peel (CP) and modified coach peel (MCP) specimens.

In this study, the effects of these parameters on the fatigue life of spot‐weld joints have been investigated. For this purpose, one of the most reliable fatigue assessment models, Coffin–Manson approach, was used. In order to accurately determine the stress and strain states, a nonlinear finite element analysis was carried out taking into account plastic deformations, residual stresses developed after unloading and contacting surfaces. The results provide designers with some guidelines to foresee the impact of design changes on fatigue strength of spot‐weld joints.
Characterizing and predicting species distributions across environments and scales: Argentine ant occurrences in the eye of the beholder
Authors: Menke S. B. , Holway D. A. , Fisher R. N. , Jetz W.
Published: October 2008

Aim  Species distribution models (SDMs) or, more specifically, ecological niche models (ENMs) are a useful and rapidly proliferating tool in ecology and global change biology. ENMs attempt to capture associations between a species and its environment and are often used to draw biological inferences, to predict potential occurrences in unoccupied regions and to forecast future distributions under environmental change. The accuracy of ENMs, however, hinges critically on the quality of occurrence data. ENMs often use haphazardly collected data rather than data collected across the full spectrum of existing environmental conditions. Moreover, it remains unclear how processes affecting ENM predictions operate at different spatial scales. The scale (i.e. grain size) of analysis may be dictated more by the sampling regime than by biologically meaningful processes. The aim of our study is to jointly quantify how issues relating to region and scale affect ENM predictions using an economically important and ecologically damaging invasive species, the Argentine ant (Linepithema humile).

Location  California, USA.

Methods  We analysed the relationship between sampling sufficiency, regional differences in environmental parameter space and cell size of analysis and resampling environmental layers using two independently collected sets of presence/absence data. Differences in variable importance were determined using model averaging and logistic regression. Model accuracy was measured with area under the curve (AUC) and Cohen's kappa.

Results  We first demonstrate that insufficient sampling of environmental parameter space can cause large errors in predicted distributions and biological interpretation. Models performed best when they were parametrized with data that sufficiently sampled environmental parameter space. Second, we show that altering the spatial grain of analysis changes the relative importance of different environmental variables. These changes apparently result from how environmental constraints and the sampling distributions of environmental variables change with spatial grain.

Conclusions  These findings have clear relevance for biological inference. Taken together, our results illustrate potentially general limitations for ENMs, especially when such models are used to predict species occurrences in novel environments. We offer basic methodological and conceptual guidelines for appropriate sampling and scale matching.