bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationship between leaf characteristics, tree sizes and species distribution along a slope in a warm temperate forest
Authors: Hanba Yuko T. , Noma Naohiko , Umeki Kiyoshi
Published: March 2003

The relationships between some leaf characteristics, tree size and species distribution were investigated for evergreen tree species along a slope in a warm temperate forest in Japan. Tree species were classified into three groups based on their dominance on the slope: ‘ridge species’ that were aggregated in an uppersite, ‘valley species’ that were aggregated in a lowersite, and ‘uniform species’ that were distributed almost uniformly. The ridge species had a more positive leaf carbon isotope ratio than the valley species, which suggests that the ridge species have larger water use efficiency than the valley species. This may give some advantage to the ridge species over the valley species in the uppersite where water availability would be limited. However, the ridge species had smaller leaf nitrogen content on a mass basis and larger leaf mass per area than the valley species, which suggests that the ridge species had a smaller mass‐based leaf photosynthetic capacity than the valley species. This may be disadvantageous to ridge species in the lowersite, because smaller leaf photosynthetic capacities cause lower leaf carbon gain and thus lower growth than the valley species. These differences in leaf characteristics between the ridge and the valley species were affected by microenvironments, and were also partly affected by the difference in species specific responses to microenvironments on the slope.
Symbiosis of a termite and a sclerotium‐forming fungus: Sclerotia mimic termite eggs
Authors: Matsuura K. , Tanaka C. , Nishida T.
Published: March 2003

Brown balls, of a similar size but different shape to termite eggs, were found frequently in the piles of eggs of the subterranean termite Reticulitermes speratus. rDNA analysis identified the ball as the sclerotia of the fungus, Fibularhizoctonia sp. nov, which is phylogenetically closest to decay fungi, Athelia spp. Laboratory observation showed that the workers gathered the eggs and the sclerotia indiscriminately, even if they were widely scattered in a Petri dish, and piled them up in a specific place for egg care. We compared the morphology of the eggs with that of sclerotia of Fibularhizoctonia spp. and Athelia spp. in relation to egg carrying behaviour, and found that the workers could only carry the Fibularhizoctonia spp. sclerotia whose diameters were similar to the short diameter of the eggs. We also conducted a bioassay using termite eggs and dummy eggs (glass beads and sea sand) of two diameter‐classes, coated with or without the egg‐derived chemicals. The workers recognized the eggs based on a combination of the size, shape, and chemical cues. All the results suggested that the sclerotia mimic the eggs both morphologically and chemically. Finally, we found that the workers suppressed germination of sclerotia, and termite egg survival increased in the presence of sclerotia only if they were tended by the workers. If the workers were removed experimentally, the sclerotia germinated and grew by exploiting termite eggs. These results suggest that the sclerotia protect termite eggs from putative pathogens.
Initial nitrogen content and topographic moisture effects on the decomposition of pine needles
Authors: Enoki Tsutomu , Kawaguchi Hideyuki
Published: March 2003

The effects of litter quality and site characteristics on the decomposition process were investigated using a litterbag method. Pine needle litters with differing nitrogen concentrations (0.8, 0.6 and 0.4%) were placed on the upper and lower slopes of aPinus thunbergiiParl. plantation. After both 3 and 6 months, the mass of decomposing litter with the lower nitrogen concentration was larger than the litter with higher nitrogen concentrations. After 9 months, there were no significant differences in the litter mass remaining, regardless of the initial nitrogen concentration. Moisture content in the litter was always higher on the lower slope, although the mass of litter was smaller. Nitrogen concentration of the decomposing litter increased linearly with accumulated mass loss. The increase in nitrogen concentration of decomposing litter was greater on the lower slope, but this increase did not differ between initial nitrogen concentrations. The nitrogen release from the decomposing litter with higher initial nitrogen concentration was larger than the release from litter bags with lower nitrogen concentrations. This result suggests that there may be positive feedback between soil nutrient availability, litter quality and nutrient release from decomposing litter at the intraspecific level.
Leaf litter decomposition of canopy trees, bamboo and moss in a montane moist evergreen broad‐leaved forest on Ailao Mountain, Yunnan, south‐west China
Authors: Liu Wenyao , Fox John E. D. , Xu Zaifu
Published: March 2003

Litter decomposition and nutrient release of selected dominant synusiae in an old‐growth, evergreen, broad‐leaved mossy forest on Ailao Mountain, Yunnan, south‐west China, were studied over a 22‐month period. The species studied were three dominant tall tree species,Lithocarpus xylocarpusMarkg.,Lithocarpus chintungensisHsu et Qian andCastanopsis wattiiA. Camus; one dominant understory species (the bambooSinarundinaria nitidaNakai); and a mixture of dominant mosses (includingHomaliodendron scalpellifoliumFleisch,Symphyodon perrottettiMont.,Herberta longifolissaSteph. andBazzania albicansHorik.). Fast initial litter decomposition was followed by lower rates. Decomposition rates of canopy species and bamboo leaf litter appear to be controlled by the initial concentration of lignin, nitrogen (N) and phosphorus (P) more than by morphological features of the leaves. The decay rate of moss litter was less correlated with nutrient composition and lignin concentration in initial mass. The order of decomposition rates wasCastanopsis wattii>L.xylocarpus>L. chintungensis>bamboo>moss. The decomposition rate constants (k) of the leaf litter for the canopy speciesL. xylocarpus, L. chintungensisandCastanopsis wattiiwere 0.62, 0.50 and 0.64, respectively, and 0.40 and 0.22 for bamboo and moss, respectively. Turnover time (1/k) for the three canopy species was 1.61 years, 2.0 years and 1.55 years, respectively, and 2.50 years and 4.55 years for bamboo and moss, respectively. The N and P concentration in the decomposing leaf litter increased in the first 6 months and then decreased over the remaining period. There was a relatively rapid initial loss of potassium (K), followed by a slight increase. Each of calcium (Ca) and magnesium (Mg) decreased with time whereas iron (Fe) and manganese (Mn) increased with time to some extent. Nutrient release from decomposing leaf litter was in the order of K > Mg > Ca > N > P > Mn > Fe, except for bamboo (Sinarundinaria nitida) K > Ca > P > N > Mg > Mn > Fe.
Effects of nutrients and arbuscular mycorrhizal colonization on the growth ofSalix gracilistylaseedlings in a nutrient‐poor fluvial bar
Authors: Sasaki Akiko , Fujiyoshi Masaaki , Shidara Sohsuke , Nakatsubo Takayuki
Published: March 2003

A field survey and a pot culture experiment were conducted to examine the effects of nutrients (N and P) and arbuscular mycorrhizal (AM) fungi on the growth ofSalix gracilistyla, a pioneer plant in riparian habitats. The plants growing in the field were colonized by AM and/or ectomycorrhizal fungi. However, the direct effect of AM colonization on seedling growth was not detected in the pot culture experiment. In contrast, N application significantly promoted plant growth, suggesting that the growth ofS. gracilistylaseedlings is largely limited by the availability of N in the field.
Morphology and growth of deciduous and evergreen broad‐leaved saplings under different light conditions in a Chinese beech forest with dense bamboo undergrowth
Authors: Cao Kun‐Fang
Published: March 2003

This study compared the morphological and growth adjustment of saplings from three shade‐ tolerant canopy species (Castanopsis lamontii, Lithocarpus hancei and Fagus lucida; Fagaceae) under different light conditions in a Chinese beech forest with dense bamboo undergrowth. Only F. lucida is deciduous, and it had the most flexible morphology. In shade, F. lucida had flat or bent topshoots and horizontal branches to maximize light interception, while in conditions of high light intensity, it formed vertical topshoots to promote growth in terms of height, and upright branches to mitigate excessive sun exposure on the leaves. In contrast to F. lucida (beech), the evergreen species always had vertical topshoots regardless of light conditions. In shady conditions, the evergreens had greater annual growth rates in terms of both height and diameter than the beech, and between the evergreens, the species bearing plagiotropic branches grew faster in diameter than the species bearing orthotropic branches. The evergreen trees had thicker leaves and thicker stems compared to the beech. It was concluded that the evergreen saplings have advantages over beech saplings in terms of current growth in the forest understorey; whereas, morphological and growth flexibility in the beech aids in its persistence in the understorey.
Value of fallow farmlands as summer habitats for waterbirds in a Japanese rural area
Authors: Fujioka Masahiro , Jr James W. Armacost , Yoshida Hoshiko , Maeda Taku
Published: March 2003

Flooded rice fields, which occupy half of the total agricultural land in Japan, are known to be foraging habitats for waterbirds. We investigated the use of various fallow fields by birds in midsummer, when rice fields are generally full of grown rice plants and are of little use for foraging waterbirds. We distinguished four types of fallow fields based on the ground cover and vegetation: (i) tall‐grass fields; (ii) wet short‐grass fields; (iii) dry fields; and (iv) flooded open fields. In August 1998 we counted birds four times in 19 survey plots of fallow fields and in seven plots of rice fields in Ibaraki Prefecture, Japan, where 82% of the farmlands are devoted to rice production. We observed 590 individual birds of 22 species, of which 15 species were waterbirds, mostly herons and shorebirds. Flooded open fields supported the largest number of species and the highest bird density, while rice fields supported the fewest. Within flooded open fields, herons preferred open‐water areas, while shorebirds used bare ground most often. Wet short‐grass fields looked similar to flooded open fields, except for the amount of short grass, but supported far fewer birds than flooded open fields. The number of birds in dry fields was comparable to that in flooded open fields, but most of the birds were ground‐foraging passerines. Our limited dataset suggests that fallow fields can serve as valuable supplemental habitats for waterbirds during summer, if they are appropriately managed to preserve flooded open fields and smaller areas of other habitats.
Organic chemical and nutrient dynamics in decomposing beech leaf litter in relation to fungal ingrowth and succession during 3‐year decomposition processes in a cool temperate deciduous forest in Japan
Authors: Osono Takashi , Takeda Hiroshi
Published: March 2003

Decomposition processes of beech leaf litter were studied over a 3‐year period in a cool temperate deciduous forest in Japan. Organic chemical and nutrient dynamics, fungal biomass and succession were followed on upper (Moder) and lower (Mull) of a forest slope. Litter decomposition rates were similar between the sites. Nutrient dynamics of the decomposing litter was categorized into two types: weight changes in nitrogen and phosphorus showed two phases, the immobilization (0–21 months) and the mobilization phase (21–35 months), while those in potassium, calcium and magnesium showed only the mobilization phase. The rate of loss of organic chemical constituents was lignin < holocellulose < soluble carbohydrate < polyphenol in order. The changes in lignocellulose index (LCI), the ratio of holocellulose in lignin and holocellulose, were significantly correlated to the changes in nitrogen and phosphorus concentrations during the decomposition. During the immobilization phase, increase in total fungal biomass contributed to the immobilization of nitrogen and phosphorus. The percentage of clamp‐bearing fungal biomass (biomass of the Basidiomycota) to total fungal biomass increased as the decomposition proceeded and was significantly correlated to LCI. Two species in the xylariaceous Ascomycota were dominantly isolated by the surface sterilization method from decomposing litter collected in the 11th month. The organic chemical, nitrogen and phosphorus dynamics during the decomposition were suggested to be related to the ingrowth, substrate utilization and succession of the Xylariaceae and the Basidiomycota. Twenty‐one species in the other Ascomycota and the Zygomycota isolated by the washing method were classified into three groups based on their occurrence patterns: primary saprophytes, litter inhabitants and secondary sugar fungi. These species showed different responses to LCI and soluble carbohydrate concentration of the litter between the groups.
Foraging and breeding performance of Japanese cormorants in relation to prey type
Authors: Kato Akiko , Watanuki Yutaka , Naito Yasuhiko
Published: March 2003

Seabirds are high trophic predators in marine ecosystems and are sensitive to change in food supply and thus seabirds can be used as monitors of the marine environment. In order to study the foraging responses of Japanese cormorants Phalacrocorax filamentosus breeding at Teuri Island, Hokkaido to changes in fish availability, the diet was assessed from the regurgitations of parents and chicks, and diving behavior was measured by using time‐depth recorders. Breeding performance (brood size, chick growth, breeding success) was monitored using conventional methods to study their breeding responses. Japanese cormorants changed the diet and foraging behavior over four summers. The birds fed mainly on epipelagic schooling fish when they were available and on demersal fish when pelagic fish availability was low. They tended to dive deeper and longer in a year when they fed mainly on demersal fish than the other years, reflecting the change in the depth distribution of prey fish. Chick growth rate did not differ among years, but fledging success was lower in the years of demersal fish as their meal delivery rate was low. When epipelagic schooling fish were considered scare, parents maintained chick growth by reducing brood size. High variability and unpredictability in pelagic fish abundance are key factors affecting the foraging and breeding performance of Japanese cormorants, which could potentially be used to monitor fish resources.
Templates of food–habitat resources for the organization of soil animals in temperate and tropical forests
Authors: Takeda Hiroshi , Abe Takuya
Published: March 2003

The functioning and structure of terrestrial ecosystems are shaped and maintained by plant–decomposer interactions. The food and habitat of animal populations are biogenic and are mainly of plant origin (plant litter) in terrestrial ecosystems. Primary resources of the food‐habitat template for the organization of soil animals are provided by the primary production of plants, and are then modified through decomposition processes by microbial populations. In the microbial decomposition system, the efficiency of carbon utilization by microbial decomposers characterizes the decomposition processes between tropical and temperate forest ecosystems. Tropical forests show poor development of soil reservoir systems because of the high efficiency of lignin decomposition by microbial populations. The decomposition processes of leaf litter are described briefly for the understanding of organization of soil animal communities in tropical and temperate forests. A comparison of decomposition processes shows qualitative differences in decomposition between temperate and tropical forests. The composition of functional groups of soil animals is well explained by the decomposition processes in both forests.
Nutritional diagnosis of phytoplankton in Lake Baikal
Authors: Genkai‐Kato Motomi , Sekino Tatsuki , Yoshida Takehito , Miyasaka Hitoshi , Khodzher Tamara V. , Belykh Olga A. , Melnik Natalia G. , Kawabata Zen’ichiro , Higashi Masahiko , Nakanishi Masami
Published: March 2003

To diagnose the nutritional status of phytoplankton in Lake Baikal, surveys for the determination of concentrations of particulate carbon (PC), nitrogen (PN) and phosphorus (PP) and their ratios were conducted at six stations in March, June, August and October 1999. The concentrations of PC and PN were lower than, and those of PP were similar to, those in another mesotrophic lake except at the station near the mouth of the largest input river, Selenga River, of Lake Baikal. The PC : PN : PP ratio was 102 : 13 : 1, considerably close to the Redfield ratio. The ratio was constant against spatiotemporal changes. These indicate that phytoplankton in Lake Baikal were exposed to no deficiency in nitrogen nor phosphorus. From a viewpoint of the nutritional status of phytoplankton, Lake Baikal might be viewed as an ocean rather than as a lake.
Copepoda – Cladocera – Tunicata: The role of three major mesozooplankton groups in pelagic food webs
Authors: Sommer Ulrich , Stibor Herwig
Published: March 2003

Copepods, cladocerans and tunicates form major groups of herbivorous mesozooplankton. The former two are found in fresh and marine waters, while the latter are restricted to marine systems. In the present review, we compile existing ecophysiological knowledge about between‐group differences in metabolic and reproductive rates, feeding selectivity and elemental composition. From this, we derive predictions about their impact on the lower trophic levels (phytoplankton and microbial food web) and predictions about their prevalence under different ecological conditions (e.g. nutrient richness, Si : N ratio, phytoplankton size structure and top‐down control).
Impacts of dugong foraging on benthic animal communities in a Thailand seagrass bed
Authors: Nakaoka Masahiro , Mukai Hiroshi , Chunhabundit Suraphol
Published: March 2003

We studied the community structure and abundance of benthic animals in intertidal seagrass beds in Thailand, where dugongs (Dugong dugon) feed on the seagrass Halophila ovalis. Our objective was to examine whether the benthic community was affected by the foraging activity of the dugongs, which can cause disturbance to the sediment. We collected a total of 4156 benthic animals from three study sites and classified them into 77 different taxa. A lucinid bivalve, Pillucina sp., was the most abundant taxa (approximately 80% of individuals). Taxa richness of the benthic animals was higher in intact H. ovalis vegetation compared to dugong trails at all sites. In general, the densities of five functional groups (classified by position on/in the sediment and motility) and five dominant taxa were higher in intact seagrass vegetation compared to dugong trails, although the magnitude of this difference varied among functional groups and taxa. Densities were at least threefold higher in the seagrass vegetation than in the dugong trails for epifauna and shallow infauna, but were at most twofold higher for deep infauna. Taxa richness and abundance of the benthic animals in the dugong trails were similar between the day following, and 7–9 days after, the creation of the trails. Thus, delayed and/or indirect effects of dugong herbivory on benthic communities were not detected in this study. These findings demonstrate that the foraging activity of dugongs in seagrass can have considerable impacts on the abundance and diversity of benthic organisms, although this effect varies among benthic animals with different lifestyles.
Anuran‐dependent predation by the giant water bug, Lethocerus deyrollei (Hemiptera: Belostomatidae), in rice fields of Japan
Authors: Hirai Toshiaki , Hidaka Kazumasa
Published: March 2003

We examined the seasonal dietary patterns of the endangered giant water bug, Lethocerus deyrollei, in rice fields located at Sayo, Hyogo Prefecture, central Japan. The results showed that L. deyrollei underwent a shift in its major food item from breeding adults of Hyla japonica in spring (May and June) to newly metamorphosed juveniles of Rana nigromaculata in summer (July to September). Dietary shifts were shown to correspond with a seasonal fluctuation in the availability of anurans in the rice fields. Although adults of R. nigromaculata were relatively abundant throughout the active season they were infrequently exploited by L. deyrollei, possibly because of the difficulty in handling these large‐sized frogs. Therefore, seasonal partitioning of the rice‐field habitat by small‐sized frogs, adult H. japonica and juvenile R. nigromaculata, would enable L. deyrollei to forage in the rice fields during the extensive active period. From these results, we suggest that the conservation of frog populations is very important for the preservation of this endangered insect and for the maintenance of biodiversity within these rice‐field ecosystems.
Seasonal changes in parotid and rumen papillary development in Mongolian gazelle (Procapra gutturosa Pallas)
Authors: JIANG ZHAOWEN , TAKATSUKI SEIKI , WANG WEN , LI JUNSHENG , JIN KUN , GAO ZHONGXIN
Published: March 2003

The Mongolian gazelle (Procapra gutturosa Pallas) lives in the Mongolian Plateau, where conditions are dry and cold from late autumn to early spring. The climate results in apparent seasonal changes in the nutrition of forage plants on the plateau. The morphology of the gazelle's rumen papillae and the weight of their salivary glands also reflect these changes. The relative weight of the parotids to body mass (0.8–1.3 g kg−1 and 1.8–2.7 g kg−0.75) and the surface enlargement factor (SEF) of the internal rumen wall (8.5–12.0) fell within the range of mixed (intermediate) feeders. Although previous studies in a great number of ruminants have shown that parotid mass and SEF are positively related to feed quality, we found that relative parotid mass to body mass increased in winter, the dry and cold season, during the poorest dietary conditions. The surface enlargement factor increased from autumn to winter and spring, during the poorest and best seasons in feed quality, respectively. It is possible that an increase in parotid mass is related to water shortage from both feed and habitat in winter. An increase in parotid mass, suggesting an increase in saliva production, could meet the liquid needs of the gazelles during feeding and rumination in poor and dry forage seasons. The development of rumen papilla and the consequent increase in SEF in poor food seasons should result in the effective absorption of nutrients by Mongolian gazelles.
Augmentation of the assassin bug Pristhesancus plagipennis (Walker) (Hemiptera: Reduviidae) as a biological control agent for Helicoverpa spp. in cotton
Authors: Grundy Paul R , Maelzer Derek A
Published: March 2003

Third‐instar nymphs of the Australian assassin bug, Pristhesancus plagipennis
(Walker), were released into cotton plots at two release densities and two crop growth
stages to test their biological control potential. Release rates of 2 and 5 nymphs
per metre row resulted in field populations of 0.51 and 1.38 nymphs per metre row,
respectively, indicating that over 70% of nymphs died or emigrated within
two weeks of release. Effective release rates of 1.38 nymphs per metre row reduced
the number of Helicoverpa spp. larvae in the plots for a 7‐week period. Crop
yields were significantly greater in the plots to which P. plagipennis nymphs
were released, with the effective release rate of 1.38 nymphs per metre row providing
equivalent yields as insecticide treated plots. The data suggest that P. plagipennis
has the capacity to reduce Helicoverpa spp. larvae densities in cotton crops when augmented through inundative release.
Emergency medicine: Where to from here? The College
Authors: Baggoley Christopher J
Published: March 2003

This paper describes two group presentations of intoxicated patients to the Emergency Department of Gold Coast Hospital in October 1996 and July 1997 respectively. A total of 14 patients received treatment. The clinical features, investigation findings and clinical course of each patient are outlined. A discussion is undertaken of the literature surrounding the emergence of gamma hydroxybutyrate (GHB) as a drug of abuse, and of the major issues involved in the emergency department management of such patients.
An introduction to statistics, significance testing and the P value
Authors: Chu Kevin
Published: March 2003

Abstract

P values come from statistical tests used for testing the null hypothesis (Ho) which states that there is no difference between treatment outcomes. If the P value is less than 0.05 there is a less than 5% probability that the difference is due to chance if the Ho is true. Given this low chance, the Ho is rejected and the alternate hypothesis (Ha) that there is a difference between treatment outcomes is accepted. In hypothesis testing, there is a risk of wrongly rejecting a true Ho (α error) and wrongly not rejecting a false Ho (β error). The t‐ and Chi‐squared tests are the two most commonly used statistical tests for clinical hypothesis testing. Statistical significance derived from such tests, needs to be clinically significant for the finding to be relevant. P values need to be interpreted with the knowledge of several statistical concepts including sample size, multiple comparisons and the validity of the study.
Adding value to the patient experience in emergency medicine: What features of the emergency department visit are most important to patients?
Authors: Holden David , Smart David
Published: March 2003

Abstract

Objectives: To identify the features of the emergency department visit most important to patients, and to compare emergency staff ranking of the same features.

Setting: The Royal Hobart Hospital, Tasmania is a 520‐bed public hospital with an annual department of emergency medicine census of 33 000.

Methods: Five hundred and fifty‐five emergency patients, and 60 emergency department medical and nursing staff were surveyed, asking each to rank 10 features of the emergency department visit in order of importance to patients. Analysis was by Chi‐squared test and Mann –Whitney U‐test to compare survey responses between the patient and staff populations.

Results: Response rates were 36% for patients and 78% for staff. Patients ranked waiting time as most important, followed by symptom relief, a caring and concerned attitude from staff and diagnosis of the presenting complaint. Staff identified the same four factors as important but ranked waiting time fourth. Waiting times during the survey week were within Australian College for Emergency Medicine performance benchmarks of 84% of the emergency department census.

Conclusions: This survey identified a mismatch between patient concerns and emergency staff perceptions, particularly with regard to waiting times. The results justify the use of waiting times as a performance indicator for emergency medicine.
The Auckland acute referral process: A survey
Authors: Peak Stephen , Maclaren Hamish
Published: March 2003

Objectives: To assess current Auckland general practitioners’ workload regarding acute referrals, perceived problems with the referral process and possible alternative methods of referral.

Methods: Data were collected by a postal questionnaire survey of 200 central Auckland general practitioners.

Results: A total of 150 responses (75%) were received. General practitioners saw, on average, 120 patients per week (range 10–300) and 1.7 patients per general practitioner per week were sent, as acute referrals, to hospital. Ninety‐two per cent of acute general practitioner referrals were preceded by a telephone call to a hospital registrar. The most common problem relating to the telephone call was the length of time the general practitioner spent waiting to speak to the registrar. The call was regarded by many general practitioners as stressful and difficult. In 19% of referrals the general practitioner felt that the patient’s diagnosis was unclear and that further investigations were needed to determine it. Ninety‐three per cent of general practitioners regarded an accompanying letter of referral as essential. Forty‐eight per cent considered a telephone call to be essential, and 60% believed the call gave added value to the referral letter. Seventy‐two per cent of the general practitioners preferred that the acutely ill patients they refer be seen by an in‐patient specialty first, rather than by emergency department medical staff.

Conclusions: While the general level of general practitioner satisfaction with the current acute referral process in Auckland is not high, there is no consensus among general practitioners about how the process could be improved.
Emergency departments have a role in the prevention of suicide
Authors: Salter Andrée , Pielage Paul
Published: March 2003

Objectives : The aims of the study were to determine whether emergency departments in Tasmania were managing patients at risk of suicide adequately, and to identify factors that may help to prevent suicide in patients who present to an emergency department.

Method
: Retrospective review of case notes of patients who had presented to Tasmanian public hospitals and were on a Coroner's list as having committed suicide in Tasmania 1995–1997 (
n = 196).

Results : This descriptive analysis of a population showed 58.7% had presented to an emergency department. Psychiatric problems were common. On the last emergency department presentation prior to death, 36.5% were admitted, with 95% of these having an admission for drug and alcohol or psychiatric problems.

Conclusions : The majority of patients seen prior to death with suicide risk were correctly identified by emergency department staff and appropriately referred. Single‐vehicle motor vehicle accident victims and patients who present on multiple occasions with psychiatric or drug and alcohol problems are at risk.
The case for prehospital thrombolysis in acute myocardial infarction
Authors: Cooke Matthew
Published: March 2003

Thrombolysis is of proven benefit in improving survival after acute myocardial infarction. The benefit decreases with time after the onset of pain; the first 2 h appear to be important. Reduction of thrombolysis times must be undertaken as a whole‐systems approach. Delays in the patient contacting assistance services are unavoidable, but once contact is made the system should ensure attendance of a qualified person within 8 min. In‐hospital delays should be decreased, aiming for a door‐to‐needle time of less than 30 min. Prehospital electrocardiographs are accurate and can help reduce in‐hospital delays. Some trials have shown that prehospital administration of thrombolysis can lead to reduced thrombolysis times. Angioplasty with or without stenting for those with contraindications to thrombolysis and as a rescue procedure needs to be considered in deciding the destination of AMI patients. More evidence is needed to support this aspect of care. Prehospital thrombolysis has an important role to play, especially when time to hospital may be prolonged.
Mild snake envenomation
Authors: Fatovich Daniel M , Hitchcock Thomas , White Julian
Published: March 2003

Snake bite envenomation typically requires treatment with effective first aid and antivenom. There is a spectrum of envenomation seen, which includes mild envenomation, but this has not been reported previously. We report two cases of mild envenomation and describe the changes in laboratory coagulation values. The patients had a benign clinical course without receiving antivenom. We strongly recommend that if clinicians are considering not treating any envenomated patients with antivenom, they do so only on expert advice.
Hospital and emergency department crowding in the United States
Authors: Schafermeyer Robert W , Asplin Brent R
Published: March 2003

Every emergency physician in the United States and, for that matter, in many countries around the world recognizes that the demand for timely access to quality emergency care is one that patients highly value. Unfortunately, hospitals in the USA have become stretched beyond capacity, resulting in overloaded emergency departments, diverted ambulances, and greater risks for patients and providers. Some of the causes and consequences of emergency department crowding are unique to the USA health care system, while others are common to countries throughout the world. The goals for this paper are to provide a brief overview of hospital and emergency department crowding in the USA, to identify commonly cited causes of the problem, and to outline future directions in the search for solutions. A large number of hospitals, inpatient beds, and emergency departments have closed during the past 10 years in the USA. In 1992 there were around 6000 hospitals with emergency departments and there are now less than 4000. While hospitals scrambled to decrease an excess supply of inpatient beds, the demand for emergency department care steadily rose. Between 1992 and 2000, the annual number of emergency department visits in the USA increased from 89.8 to 108 million. While some areas of the USA have been affected more seriously than others (particularly the coasts), almost every state has reported problems with boarding of inpatients in the emergency department. Inpatient boarding is the most frequently cited reason for emergency department crowding within the emergency medicine community. United States hospitals are also struggling with a shortage of health care professionals, particularly registered nurses. There are several policy issues that must be addressed to alleviate hospital and emergency department crowding over the long term. We list these as ‘long‐term’ goals simply because policy changes, in the USA, are often incremental and rarely occur quickly. In order to achieve any of these changes in policy over the long term, advocates for reform must aggressively pursue them today.
Unusual multiple endocrine neoplasia
Authors: Artioukh Dmitri , Al‐Jafari Mohammad , Wake Phillip
Published: March 2003

An unusual case of multiple endocrine neoplasia (MEN) is reported. A 64‐year old male was found on investigation to have neoplastic lesions involving thyroid, parathyroid, pituitary and adrenal glands. The adrenal neoplasm shared features of a biochemically silent phaeochromocytoma and an oestrogen‐secreting cortical tumour. This association in the same neoplastic mass has not previously been described in conjunction with MEN syndrome.

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Does appendix position affect the clinical outcome of acute appendicitis?
Authors: Chan Wai‐To , Cheng Naomi Hau‐Yin , Cheng Kwan‐Chui , Cheung Kitty Kit‐Ting , Cheung Mam‐Hung , Ho Karin Kar‐Huen , Huen Lok‐Lam , Lee Janet Fung‐Yee , Leung Ka‐Lau
Published: March 2003

Objective: To elucidate if the course of acute appendicitis is influenced by the variable positions of the appendix. The appendix positions were divided into two groups: (i) the anterior group, which included the anterior, the pelvic and the paracaecal positions; and (ii) the posterior group, which included the retrocaecal and retroileal positions.

Method: The hospital records of 161 patients who underwent appendectomy for acute appendicitis from January 2000 to June 2001 at Prince of Wales Hospital were reviewed retrospectively.

Results: Clinicians’ delay in reaching the diagnosis was longer in the posterior group (9.9 h vs 5.8 h; P=0.043). However, complicated appendicitis (gangrenous changes, perforation or abscess formation) was not associated with the appendix location (P = 0.078). The median operating time for laparoscopic appendectomies lasted longer in the posterior group (77.5 min vs 60 min; P = 0.02). These patients also had a longer hospital stay (6 days vs 4 days; P = 0.049). No difference was observed among patients who underwent open surgery.

Conclusion: Appendices in the ‘hidden’ position did not translate into a higher incidence of complicated appendicitis or postoperative complications except for the slightly longer hospital stay in patients treated by laparoscopy. Therefore, we concluded that the location of appendices does not affect the clinical course of appendicitis in the locality studied.
The effect of water content on the 193 nm excimer laser ablation
Authors: Feltham Mark H , Stapleton Fiona
Published: March 2003

Background: Water content of the corneal stroma may influence
excimer laser ablation and may therefore affect residual refractive
error following laser in situ keratomileusis. This study reports associations between water content of hydrogel materials and laser ablation depth.

Methods: Hydrated (n = 4)
and dehydrated (n = 4) hydrogel buttons of 38%, 45%, 55% and 69% water content were ablated with the Nidek EC‐5000 ArF 193 nm excimer laser, set to deliver a ‐6.00 DS curvature. Central curvature, optical quality and water content were measured before and after ablation. Hydrated buttons were rehydrated postablation and prior to measurement, to eliminate the effect of water removal during the procedure. The ablation depth per pulse was calculated.

Results: The average ablation rate for fully hydrated
buttons was 0.51 ± 0.17 µm.
The ablation rate for hydrated mat­erials (dry component
ablation) reduced with increasing water content (P < 0.001). Dry hydrogel materials (0% water content) had an average ablation rate of 0.23 ± 0.06 µm per pulse.

Conclusions: For a constant laser energy output, lower water
content materials ablated to a greater extent than higher water
content materials. This model provides a simple way to assess the
effect of water content and dehydration on myopic laser in situ keratomileusis.
Quantitative analysis of apoptosis in retinoblastoma
Authors: Tatlipinar Sinan , Söylemezoglu Figen , Kiratli Hayyam , Bilgiç Sevgül
Published: March 2003

Purpose: The rate of apoptosis in retinoblastoma (Rb) and the factors that may influence this rate, such as therapy prior to surgery, amount of necrosis in tumour tissue, differentiation and laterality of the tumour, were investigated.

Methods: Thirty‐one specimens (25 enucleation, six exenteration) with Rb were studied. Prior to final surgery, three patients received systemic chemotherapy, one intravitreal chemotherapy, one transpupillary thermotherapy, one external beam radiotherapy and one high‐dose oral methylprednisolone therapy. The apoptotic index (AI,%) was calculated by counting at least 1000 cells under light microscopy (× 100) using TUNEL (terminal deoxynu­cleotidyl transferase‐mediated dUTP nick‐end labelling) method.

Results: The mean AI was 2.75 ± 1.2. No statistically significant association was observed between rate of apoptosis and the presurgical treatment, extent of necrosis, tumour differentiation and laterality.

Conclusion: Apoptosis is an important mechanism of cell death, and may be a limiting factor for tumour progression. In this study, the rate of apoptosis was not affected by any of the studied parameters.
Delivery of photocoagulation treatment for diabetic retinopathy at a large Australian ophthalmic hospital: comparisons with national clinical practice guidelines
Authors: Bamroongsuk Parapun , Yi Qing , Harper C Alex , McCarty Daniel J
Published: March 2003

Objective: To determine if the delivery of photocoagulation for diabetic retinopathy at a large Australian ophthalmic hospital conforms with Australian National Health and Medical Research Council clinical practice guidelines.

Methods: A retrospective medical record review was conducted of all patients who had initial laser treatment for diabetic retinopathy at the Royal Victorian Eye and Ear Hospital from January 1997 to December 1998.

Results: The study included 322 eyes from 203 patients. The mean age was 65.8 years (range 18−89 years) and the mean duration of diabetes was 14.7 years (range 1−40 years). Panretinal photocoagulation (PRP) alone was performed in 37 eyes over a mean number of 2.6 sessions. The median waiting time for these procedures was 14 days (range 0−146 days) and the median follow‐up time was 7.1 weeks (range 1−25 weeks). Focal treatment was performed (without PRP) in 238 eyes and 55.5% of these cases required repeat focal treatment for persistent clinically significant macular oedema. Median waiting time for focal treatment was 20 days (range 0−302 days) and the median follow‐up time after treatment was 12.1 weeks (range 1.7−42.0 weeks). Focal and PRP treatment was used in 47 eyes that had maculopathy concurrently with proliferative retinopathy. Focal treatment was applied before (or at the same session as) the PRP wherever possible.

Conclusions: The study indicates that the application of photocoagulation and follow up for diabetic retinopathy at this tertiary referral institution conforms closely with Australian clinical practice guidelines.
Potential for biofilms as biological indicators in Australian riverine systems
Authors: Burns Adrienne , Ryder Darren S.
Published: March 2003

Summary Biological indicators have been widely used in Australian riverine systems to assess the effectiveness of past and current management. The short generation time, sessile nature, responsiveness to environmental conditions and the availability of sound, quantitative methodologies make biofilms suitable as a monitoring tool in these systems. This paper describes biofilm structure, function and development through the processes of succession and disturbance. Biofilms are assemblages of algae, fungi and microorganisms which cover rocks, wood and sediments in aquatic systems. A review of biofilm collection and processing techniques using relevant Australian and international studies reveals a large literature on many structural and functional biofilm attributes. Studies using structural attributes such as biomass and diversity to examine water quality impacts and invertebrate grazers dominate the Australian literature. More recently, studies have used functional biofilm attributes such as metabolism and foodweb interactions. Monitoring programs that combine structural and functional biofilm attributes will allow the best assessment of impacts in riverine systems. Biofilm functional parameters provide an integrated, long‐term measure of ecosystem function, with structural attributes such as biomass and diversity allowing historical comparisons with previously recorded datasets. Monitoring programs such as these with a well‐founded scientific base and defined management outcomes will expand our knowledge of river function and contribute to the restoration of Australian river systems.
Vitreal macrophages express vascular endothelial growth factor in oxygen‐induced retinopathy
Authors: Naug H L , Browning J , Gole G A , Gobé G
Published: March 2003

Purpose: The possibility of vitreal macrophages playing an angiogenic role in oxygen‐induced retinopathy (OIR) was investigated. Oxygen‐induced retinopathy was produced in newborn animals with the purpose of modeling the proliferative phase of human retinopathy of prematurity (ROP).

Materials and Methods: To produce OIR in neonatal mice, litters at postnatal day 7 were placed in 80–90% oxygen for a period of 5 days and then returned to room air. Pups were killed on days 7, 12, 15, 17 and 20 over the postnatal period and were perfusion‐fixed using a saline wash‐out, followed by 4% paraformaldehyde and then India Ink. Eyes were enucleated and either whole‐mounted, or snap‐frozen and cryosectioned. Immunostaining procedures were used to visualize macrophages and vascular endothelial growth factor (VEGF) protein. The primary antibodies used were anti‐F4/80 and antimouse VEGF, respectively. Vitreal macrophages closely associated with the vitreo–retinal interface (within 25 μm of the inner limiting membrane) were counted. In situ hybridization procedures were used to analyse for the presence of VEGF mRNA transcript in vitreal macrophages.

Results: Macrophage numbers were found to significantly increase (P < 0.05) in eyes from oxygen‐treated animals compared with those from age‐matched controls. A close spatial relationship was observed between macrophages and vitreal neovascular sprouts. In addition, vitreal macrophages were also found to transcribe and express VEGF in the oxygen‐treated animals during the vasoproliferative phase.

Conclusions: Our results raise the possibility that vitreal macrophages play a role in the pathogenesis of OIR and by inference, ROP.
Visual function tests, eye disease and symptoms of visual disability: a population‐based assessment
Authors: Ivers Rebecca Q , Mitchell Paul , Cumming Robert G
Published: March 2003

Purpose: To examine associations between eye disease and tests of visual function with self‐reported visual disability.

Methods: The Blue Mountains Eye Study is a cross‐sectional census‐based survey of eye disease in two postcode areas in the Blue Mountains, west of Sydney, Australia. Of 4433 eligible residents, 3654 (82.4%) participated. Subjects had a detailed eye examination, including tests of visual acuity, contrast sensitivity, disability glare and visual field. Lens and retinal photographs were taken and graded according to standardized protocols for presence of cataract, early and late age‐related maculopathy, glaucoma, diabetic retinopathy, retinal vein occlusion and other eye diseases. An interviewer‐administered questionnaire included questions about perception of visual disability.

Results: Scores on all tests of visual function significantly decreased with age (P < 0.0001). This decrease persisted for all tests except disability glare after excluding subjects with identifiable eye disease. The presence of one or more eye diseases was significantly associated with all (self‐reported) measures of visual disability (trouble driving at night, difficulty recognizing a friend across the street, reading a newspaper or recognizing detail on television); mixed cataract (cortical and nuclear, or posterior subcapsular and nuclear) was associated with trouble driving at night and difficulty recognizing a friend across the street. A 10‐letter (two‐line) decrease in best corrected or presenting visual acuity was significantly associated with all self‐reported measures of visual disability, as was a two‐step decrease in contrast sensitivity. A five‐point increase in points missing in the visual field was weakly but significantly associated with all self‐reported measures of visual disability except trouble driving at night.

Conclusions: Visual function declines with age. Impaired visual function was strongly, and eye disease relatively weakly associated with reports of visual disability.
Diplopia from peribulbar ropivicaine
Authors: Wells Anthony P , Maslin Keith
Published: March 2003

Purpose: To report a previously undescribed side‐effect of ropivicaine (Naropin) used in peribulbar anaesthesia.

Methods: We report nine cases identified prospectively with symptomatic diplopia, predominantly vertical, following Ropivicaine use for peribulbar anaesthesia in routine cataract surgery. These nine cases occurred in a 10‐week period from a total of 77 patients given 7 mL peribulbar ropivicaine (10 mg/mL) with 750 units hyalase prior to cataract extraction by a single surgical team.

Results: None of the cases had preoperative ocular motility disturbances and none had superior rectus traction sutures. All diplopia resolved in less than 30 h.

Conclusions: Ropivicaine may have a prolonged motor block resulting in diplopia of up to 30 h duration after peribulbar anaesthesia.