bluuebunny/crossref_metadata_2025_split huggingface dataset:
Terrestrial activity, movements and spatial ecology of an Australian freshwater turtle, Chelodina longicollis, in a temporally dynamic wetland system
Authors: ROE JOHN H. , GEORGES ARTHUR 
Published: August 2010

AbstractAnimal movements, use of space, activity patterns and habitat use are in part determined by proximal factors such as the landscapes they occupy, seasonal or environmental cues and individual attributes such as sex and body size. Using radio‐telemetry and a drift fence, we examined the contribution of these factors to variation in movements, use of space and terrestrial activity in a freshwater turtle, Chelodina longicollis (Testudines: Chelidae), in south‐east Australia. Movements and use of space depended strongly on landscape attributes, while sex and body size were less important. Movements and use of space also varied seasonally and were partly correlated with rainfall. The high overall vagility of turtles, irrespective of sex and adult body size (13.8 ± 2.8 ha (±SE) home range, 2608 ± 305 m total distance moved, 757 ± 76 m range length), probably reflects a common need to be mobile in a landscape characterized by fluctuating resources in temporary wetlands. Use of temporary wetlands also drives C. longicollis into terrestrial habitats for movements between wetlands and extended refuge. Timing of inter‐wetland movements was associated with rainfall, but most notably for immature individuals and for those moving towards temporary wetlands. Movements of adults, evacuation of the drying wetland and periods of extended refuge (i.e. aestivation) were less dependent upon rainfall if at all. We conclude that movements about and use of the landscape by C. longicollis are under the strong influence of several interacting factors such as patch configuration, seasonal and environmental cues, and in part, body size. We argue that such behaviours are also ultimately under selection from the costs and benefits of these behaviours in the context of fluctuating resources.
Innovation and dynamism
Authors: Kornai János 
Published: August 2010

AbstractLiterature on post‐socialist transformation usually deals with the political, economic and social sides of it, although there have also been important changes in the field of technical advance in the last twenty years. One of capitalism's main virtues is the strong incentive it gives to dynamism, enterprise and the innovation process. Every revolutionary new product (for civilian use) has been brought about by the capitalist system. The socialist system was capable at most of developing new military products. The article analyzes how far the radical difference can be explained by the innate tendencies and basic attributes of the two systems. Our daily lives have been transformed by these new products (for instance, the sphere of information and communications by the computer, the mobile phone and the internet). While many people see all these as favourable changes, fewer discern the causal relation between the capitalist system and rapid technical progress. Yet the usual syllabus of microeconomics does not enlighten students on this important virtue of capitalism, neither it is not adequately emphasized in the statements of leading politicians.
The food and feeding ecology of Adélie penguins (Pygoscelis adeliae) and Chinstrap penguins (P. antarctica) at Signy Island, South Orkney Islands
Authors: Lishman G. S. 
Published: August 2010

Adélie Pygoscelis adeliae and Chinstrap P. antarctica penguins are important consumers of Southern Ocean marine resources. The stomach contents of adult penguins at Signy Island, South Orkney Islands, were analysed quantitatively throughout the chick‐rearing period. They consisted almost exclusively of Antarctic krill Euphausia superba, Adélies eating 35–63% by number and 23–28% by weight of juvenile krill and Chinstraps 72–87% by number and 90–95% by weight of mature krill, as well as small amounts offish and amphipods. Interspecific dietary differences may partly be attributable to Adélies starting breeding one month before Chinstraps but, as they persist when both are simultaneously rearing chicks, the two species may also forage in somewhat different areas.Krill data from net hauls indicate a substantial overlap in the size of krill taken by scientific, and probably also commercial, operations and by Adélie and Chinstrap penguins.Chicks were fed c. 300 g of food 0–5‐0‐8 times per day, Chinstrap chicks without a sibling being fed most frequently. Chicks of both species were most often fed in the late afternoon, and from estimates of swimming speed and feeding frequency adults may feed quite extensively at night.
Larval development and metamorphosis in the marine pulmonate Amphibola crenata (Mollusca: Pulmonata)
Authors: Little C. , Stirling Penny , Pilkington Margaret , Pilkington J. 
Published: August 2010

The development of the free‐swimming veliger of Amphibola is followed from hatching to settlement, and the larval structures compared with those of post‐metamorphic juveniles and adult snails. Observations of living specimens and light‐microscope sections were combined with scanning electron microscopy to build up a composite picture of veliger structure.Four stages in the development of veligers are recognized, each being characterized by the appearance of organ systems such as the mantle cavity, larval heart, adult heart and kidney, and larval pallial gland. At or after metamorphosis, the larval systems (heart, kidney and pallial gland) disappear, and the developing adult organs move to the positions characteristic of adult snails.Organogenesis in Amphibola veligers is compared with that of prosobranch and opisthobranch larvae, and with that of pulmonate larvae with direct development. The closest similarity is seen to be with opisthobranch veligers.
Influences of weather on reproductive function in male Song sparrows, Melospiza melodia
Authors: Wingfield John C. 
Published: August 2010

The avian reproductive cycle is integrated and timed by a variety of environmental factors that include day length, availability of food, nest sites, presence of a mate, etc. However, reproduction can be delayed or disrupted by inclement weather and, until recently, the endocrine responses of avian species to storms were entirely unknown. This communication describes changes in endocrine state in free‐living male Song sparrows, Melospiza melodia, during gonadal recrudescence after a severe winter, and in response to storms in early spring and summer. Both the severe winter weather and an early spring snow storm delayed testicular development, and depressed circulating levels of testosterone. The sparrows did not appear to be stressed, however, since body mass and fat deposits were higher than in birds sampled during the previous spring after a less severe winter.A second storm occurred in late May and early June when Song sparrows were feeding young. Curiously, plasma levels of testosterone were not affected, but the sparrows did appear to be stressed since there was a significant decline in body mass, and a marked increase in circulating levels of corticosterone. These data suggest that the effects of inclement weather on reproductive function can vary in relation to the stage in the reproductive cycle when the storm strikes, and that the endocrine mechanisms underlying acclimatization to severe meteorological conditions are also different.
Energy requirements of a Great white pelican (Pelecanus onocrotalus) population and its impact on fish stocks
Authors: Guillet A. , Furness R. W. 
Published: August 2010

The Great white pelican Pelecanus onocrotalus is a major predator of some freshwater fish stocks in much of Africa. Detailed population time‐activity budgets allowed us to estimate that the south‐western Cape Province population consumed 184 tonnes offish annually. Of this, 69% was required for adult existence, 17% for chicks and 14% for flight. Per capita consumption averaged 840 g per day, or 8–8% of body weight; very much less than the figure of 17–6% used in some energy budget calculations. Our integrative bioenergetics approach lends some support for the use of 10% of body weight as the amount of food consumed per day by large piscivorous birds for initial estimates of their impact on stocks.Predation by Great white pelicans may account for some 10–25% offish production, a shortage of reliable data on fish production in African freshwater ecosystems makes a more precise estimate impossible. Food supplies and shoreline length may both be important factors for pelican populations.
Relative brain size and ecology in birds
Authors: Bennett P. M. , Harvey P. H. 
Published: August 2010

We test the hypothesis that the relative sizes of the different parts of the brain (brain stem, optic lobes, cerebellum and cerebral hemispheres), measured after body size effects have been removed, are associated with differences in behaviour and ecology across bird species.The results demonstrate that behavioural and ecological correlates of relative brain size are not independent of each other. When the effects of variation in other categories are accounted for, the strongest single effect is due to relatively large brain sizes being associated with altricial development. It is unlikely that this effect is due to the confounding influence of taxonomic associations.Overall, the results do not provide support for the idea that differences in measures of environmental complexity select for differences in relative brain size.
Microhabitat choice and high temperature tolerance in the land snail Theba pisana (Mollusca: Gastropoda)
Authors: Cowie Robert H. 
Published: August 2010

Adults of the land snail Theba pisana near the species’northern limit (Tenby. South Wales) spend the daytime inactive attached to stems of tall vegetation, avoiding higher temperatures near the ground, while juveniles remain low down. This may be related to the lesser ability of juveniles to withstand desiccation for long periods, and/or to their requiremcnts for an easily accessible source of suitable food during growth. In the field and laboratory, adults (at least) respond to light and wind direction, avoiding the hottest and most exposed sides of stems on which they rest.The upper lethal temperature of snails from S. Wales lies between 42 and 46 °C, depending on exposure time. Juveniles are more tolerant than adults, probably because of their greater ability to use evaporative cooling for short periods. Spanish T. pisana are more tolerant (upper lethal limit 46–50 °C) than Tenhy snails; this difference may have a genetic basis. Aestivating Spanish snails are more tolerant than active ones.Climbing and orientation are essential for both adults and juvenilcs in the Mediterranean habitats where Theba pisana evolved, since ground temperatures can exceed the lethal limit. It is less important at the northern edge of the range, but is still retained by the adults.
Brain size, development and metabolism in birds and mammals
Authors: Bennett Peter M. , Harvey Paul H. 
Published: August 2010

Recent hypotheses that variation in brain size among birds and mammals result from differences in metabolic allocation during ontogeny are tested.Indices of embryonic and post‐embryonic brain growth are defined. Precocial birds and mammals have high embryonic brain growth indices which are compensated for by low post‐embryonic indices (with the exception of Homo supiens). In contrast, altricial birds and mammals have low embryonic and high post‐embryonic indices. Altricial birds have relatively small brains at hatching and develop relatively large brains as adults, but among mammals there is no equivalent correlation between variation in adult relative brain sizes and state of neonatal development.Compensatory brain development in both birds and mammals is associated with compensatory parental metabolic allocation. In comparison with altricial development, precocial development is characterized by higher levels of brain growth and parental metabolic allocation prior to hatching or birth and lower levels subsequently. Differences between degrees of postnatal investment by the parents in the young of precocial birds versus precocial mammals may result in the different patterns of adult brain size associated with precociality versus altriciality in the two groups.The allometric exponent scaling brain on body size differs among taxonomic levels in birds. The exponent is higher for some parts of the brain than others, irrespective of taxonomic level. Unlike mammals, the exponents for birds do not show a general increase with taxonomic level. These pattcrns call into question recent interpretations of the allometric exponent in birds. and the reason for changes in exponent with taxonomic level.
Gonadal cycles and levels of luteinizing hormone in wild Spur‐winged geese, Plectropterus gambensis
Authors: Halse S. A. 
Published: August 2010

The gonadal cycles of wild Spur‐winged geese at Barberspan, South Africa, were examined histologically. Changes in 13 testicular parameters and penis weight and 12 ovarian and oviducal parameters were quantified. Concentrations of luteinizing hormone (LH) in the plasma were measured in both sexes. It was found that, in terms of their histology, the gonadal cycles of Spur‐winged geese fit conventional avian patterns. The occurrence of follicular atresia in the ovary is discussed.In males, the testes of juvenile birds (< 1 yr. old) begin developing at least a month later than those of adults; in juvenile females the ovary often does not develop at all. However, in both sexes, LH levels in juveniles appear to rise simultaneously with those in adults and to reach similar values.It seems likely that LH release and gonadal recrudescence in Spur‐winged geese are under the dual control of photoperiod and some rain‐associated factor(s). However, additional cues are required to stimulate the final stages of ovarian development in females. These are probably suitable water depth, suitable nesting cover, rainfall per se and having a mate.
Effects of size, sex, temperature and condition on activity metabolism and defence behaviour of the viperine snake, Natrix maura
Authors: Hailety A. , Davies P. M. C. 
Published: August 2010

The activity metabolism (aerobic and anaerobic), performance (burst speed and endurance) and defence behaviour (static or active) of the snake Natrix maura were investigated in relation to size, sex, temperature and fasting. Conditions which reduced performance (low temperature, fasting) promoted the use of static defensive behaviour. Aerobic scope for activity decreased with increasing size, but this was compensated for by increased capacity for anaerobic metabolism. Burst speed (as lengths time‐1) was slightly lower in large snakes; endurance was much lower in small snakes. Increased use of static defence by small snakes is related to their predators, which are likely to take occasional snakes in a diet of worms; a balled, still snake may not provide a stimulus for feeding. Large snakes have predators which feed on vertebrates and may recognize them as food in any position, and so they are better off trying to escape.Aerobic scope was not maximal at the mean selected body temperature (25 °C), but increased right up to near lethal temperatures (> 35 °C). Anaerobic metabolism (lactate production) was less temperature‐sensitive, and accounted for about 80 and 50% of the energy produced during 30 and 5 min of maximal activity, respectively. Resting and active oxygen consumption were weight‐dependent, VO2∝ W0·75, the same exponent as that of interspecific comparisons. This exponent was independent of temperature and acclimation state. Acclimation to a variable or constant temperature regime had no effect on maximal oxygen consumption, but there was a significant effect on resting metabolic rate, possibly attributable to energy conservation when inactive. There were no differences in activity metabolism, performance or defence behaviour between similar‐sized snakes of different sexes.
The wing musculature of the Weka (Gallirallus australis), a flightless rail endemic to New Zealand
Authors: McGowan C. 
Published: August 2010

The pectoral musculature of the Weka, a flightless New Zealand rail, is almost identical with that of a volant relative, the American coot, even to details of the propatagial complex. Similar observations have been made for other flightless carinates, including ducks and cormorants (Lowe 1928a, 1934, 1935). Ratites, in contrast, have far fewer wing muscles than carinates, and lack a propatagium (Lowe, 1928b; McGowan, 1982). The fact that the loss of flight in carinates is accompanied by such little change in the pectoral musculature, while that of ratites is so radically different, weakens the hypothesis that ratites evolved from carinates through the loss of flight.An assessment of the relationship between muscles and their bony attachment areas shows how little myological information can be deduced from the surface features of bones. Thus, not even the vaguest of muscle reconstructions could have been attempted by studying the pectoral skeleton of the Weka, and similar findings have been made elsewhere (McGowan, 1979, 1982). This raises serious doubts on the validity of reconstructing the musculature of extinct vertebrates, a matter of much interest to palaeontologists.
The population dynamics and life history tactics of Pisidium clarkeanum and P. annandalei (Bivalvia: Pisidiidae) sympatric in Hong Kong
Authors: Morton Brian 
Published: August 2010

This study is of sympatric species of Pisidium inhabiting an artificially managed flooded vegetable furrow in the New Territories of Hong Kong. It extended over 16 months during 1983–84.Because of Hong Kong's subtropical climate, the habitat is strongly seasonally influenced with regard to temperature, and is flushed by summer rains. Normally, such a habitat would be ephemeral, drying in winter; flushed in summer. The water is acidic, soft and would typically be slow‐moving and nutrient deficient, but because of agricultural practices it is periodically culturally eutrophicated.The pisidiids inhabiting the furrow show life history tactics which favour the habitation of a normally ephemeral subtropical habitat. Three birth periods occur each year, typically in winter, spring and in either summer (P. clarkeanum) or autumn (P. annandalei). Each generation is largely the product of the previous one. Pisidium clarkeanum attains a maximum shell length of 7.0 mm, sexual maturity at 2.5 mm and shelled larvae are present in the ctenidia at 3.5 mm. Average larval brood size is 9.49. Pisidium clarkeanum is generally univoltine and semelparous, though there is the probability that some individuals may produce one litter, continue to grow and contibute to the succeeding generation. These individuals are thus iteroparous and bivoltine. Pisidium annandalei, on the other hand, is a small species, with a recorded maximum shell length of 4.0 mm. It is born at 0.8 mm shell length and attains sexual maturity at 1.5 mm. Larvae are brooded from a parental length of 2.0 mm, average brood size being 7.17. Pisidium annandalei is typically univoltine and strongly semelparous, with the possibility only (as compared with the probability of this occurring in P. clarkeanum) of one or two individuals of the winter and spring recruits only surviving to be iteroparous and bivoltine. Autumn recruits are always univoltine as the following winter results in total adult mortality.The life history tactics of these two pisidiids are therefore similar and represent adaptations to ephemeral habitats in subtropical and tropical Asia. Hong Kong's other freshwater bivalves are discussed: all are occupants either of other ephemeral lotie or more predictable lentic and lotie systems and show adaptations appropriate to these habitats.
Associations of zooplankton in six crater lakes in Arizona, Mexico and New Mexico
Authors: Green J. 
Published: August 2010

Zooplankton associations in six crater lakes have been compared by means of indices of similarity and diversity, and by k‐dominance curves. The lakes covered a wide range of salinities and vegetational characteristics.The total number of species identified were: Protozoa, 34; Rotifera, 48; Gastrotricha, 7; Crustacea, 24; and Chaoborus larvae, 2; giving an overall total of 115. The numbers of zooplankton species in each lake varied from 68, in a richly vegetated fresh crater lake in Arizona, to one in a highly saline lake in New Mexico.Testate rhizopods and gastrotrichs were not found in the more saline lakes. A comparison of the rotifer associations with those of crater lakes in other parts of the world shows that there is a general tendency for a reduction in the total number of species when the conductivity rises above 400 μS cm−1 20°C, and when the conductivity reaches 10,000 μS cm−1 20°C the number of rotifer species is usually reduced to two. The two species found at high salinities show some variation in different parts of the world, but generally include species of Brachionus and Hexarthra.There is a general tendency for the number of rotifer species in a crater lake to increase with increasing vegetation, at least up to the stage where there is a dense, zoned vegetation, and before a complete mosaic of vegetation covers the lake.
Activation of a nuclear factor of activated T‐lymphocyte‐3 (NFAT3) by oxidative stress in carboplatin‐mediated renal apoptosis
Authors: Lin Heng , Sue Yuh‐Mou , Chou Ying , Cheng Ching‐Feng , Chang Chih‐Cheng , Li Hsiao‐Fen , Chen Chien‐Chang , Juan Shu‐Hui 
Published: August 2010

BACKGROUND AND PURPOSEAlthough carboplatin is currently used as a therapeutic drug for ovarian, breast, and non‐small cell lung cancers, it has serious side effects including renal and cardiac toxicity. Herein, we examined the effect of carboplatin on murine renal tubular cell (RTC) apoptosis bothin vivoandin vitroand the underlying molecular mechanisms associated with its activation of the nuclear factor of activated T‐lymphocytes‐3 (NFAT3).EXPERIMENTAL APPROACHMechanisms of carboplatin‐mediated renal apoptosis were examined using NFAT‐reporter transgenic mice and RTCs with NFAT3 overexpression or knockdown.KEY RESULTSWe demonstrated that carboplatin initiated an intrinsic apoptotic pathway of activating caspase‐3 and ‐9, accompanied by a decrease in the ratio of Bcl‐XL/Bax and a significant increase in Bcl‐XS. Carboplatin increased NFAT activation in NFAT‐luciferase reporter transgenic mice, RTCs and cells exogenously overexpressing NFAT3 that exacerbated cell death. Furthermore, the addition of either N‐acetylcysteine (NAC, an antioxidant) or NFAT inhibitors, including FK‐506 (tacrolimus), cyclosporin A (CsA, a calcineurin inhibitor), and BAPTA‐AM (a calcium chelator) successfully reversed carboplatin‐mediated cell apoptosis, which was further confirmed using siNFAT3. Additionally, NAC blocked NFAT3 activation by inhibition of NADPH oxidase activation, and ERK/JNK and PKC pathways, resulting in a decrease in cell apoptosis; the therapeutic effect of NAC was verifiedin vivo.CONCLUSION AND IMPLICATIONSThe results presented herein show that carboplatin‐mediated reactive oxygen species might signal calcineurin and NFAT3 activation in RTCs, whereas NAC and NFAT inhibitors reversed carboplatin‐mediated RTC apoptosis, suggesting that oxidative stress‐mediated NFAT3 activation is essential for carboplatin‐mediated RTC apoptosis.