bluuebunny/crossref_metadata_2025_split huggingface dataset:
Causes of mortality in the Mute swan Cygnus olor on the River Thames
Authors: Birkhead Mike 
Published: August 2009

Over the last 20 years there has been an unprecedented decline of the Mute swan on the River Thames. Between August 1979 and October 1981 a systematic attempt was made to collect as many swan corpses as possible. Of 94 swan corpses examined at post‐mortem 57% died from lead poisoning due to ingestion of anglers' weights. Birds dying from lead poisoning had significantly higher liver and kidney lead levels. Kidney proved to be the most useful indicator tissue, the median lead level in birds with lead weights in their gizzard was 908 μg/g DM compared to 8 μg/g DM in birds without weights. More immature birds die from lead poisoning than other factors and significantly more corpses were found between the months of July‐October.Ultra‐structure examinations revealed electron dense intra‐nuclear inclusions in the cells of proximal convulated tubules of the kidney and X‐ray analysis confirmed that these structures consisted of lead.
The influence of temperature on the life cycle and occurrence of three species of lake‐dwelling leeches (Annelida: Hirudinea)
Authors: Young J. O. , Ironmonger J. W. 
Published: August 2009

The influence of constant temperatures on the growth, maturation and reproduction of field‐collected and F, generation Helobdella stagnalis, Glossiphonia complanata and Erpobdella octoculata was investigated. Leech material from a lowland, productive lake and from an upland, unproductive lake was cultured at each of the temperatures: l·5,5·5,8, 10·5, 13,16, 19 and 23°C. Field‐collected and F1 generation H. stagnalis and E. octoculata matured and produced eggs and young over the range 10·5–23°C, whereas the range for egg production was 8–23°C for field‐collected G. complanata, F, generation leeches failing to mature at any temperature due to an additional limiting factor being involved.Optimal temperatures for cocoon/egg production were observed for E. octoculata, but egg production was similar at all temperatures for G. complanata and H. stagnalis. In contrast, the viability of eggs was greater at certain temperatures for the last two species but was similar at all temperatures for E. octoculata. Differences in egg production between field‐collected and F, generation leeches are discussed. Rising temperatures accelerated rates of egg hatching, and of growth and maturation of leeches. The observed differences in survival of leeches at the various temperatures are discussed. Ecotypic adaptation to temperature within the small geographical area of Britain may not occur. It is concluded that though temperature may be a contributory factor determining distribution and abundance in British lakes, other causative factors, such as the occurrence and abundance of food organisms, are more likely to be implicated.
Morphology of the Hooded crow Corvus corone cornix in relation to age, sex and latitude
Authors: Slagsvold T. 
Published: August 2009

The morphological variation of the Hooded crow at Trondheim, Norway, was studied, based on a sample of 734 birds collected during a six year period. Mouth colour, plumage colour, skull thickness and feather length were found to be characters which could readily be used to separate juveniles from adults. Females aged 15–19 months had a thinner skull roof than older female birds. Low coefficients of variation were found for the lengths of the third primary and of the tail feathers. A discriminant analysis showed that of the various body dimensions studied bill height and bill length distinguished the sexes most precisely. A high degree of sexual dimorphism was also found to exist in body weight and in the thickness of the skull roof.Those body structures which develop at about the same stage during the juvenile growth period were associated with the same principal component, viz. the lengths of bony structures, parts that develop early on in life, were intercorrelated (wing bones, tarsus, bill basis and the width of foramen magnum). The lengths of the primaries and of tail feathers were also intercorrelated, structures which develop late.The mean body weight of the Hooded crow population studied in Norway was intermediate between that of the Hooded crow in Germany and of the Carrion and Hooded crows in England and Scotland. No such differences were found in wing length. Norwegian Hooded crows have shorter tails than German ones, but their bills are much larger, in particular for the females. Therefore, the degree of sexual dimorphism in bill size seems to be reduced at high latitudes.
Reproduction of the Australian freshwater turtle Emydura krefftii (Chelonia: Chelidae)
Authors: Georges Arthur 
Published: August 2009

A study of the reproduction of Krefft's river tortoise, Emydura krefftii, was conducted in the perched dune lakes of Fraser Island, Queensland. Mature male specimens exhibit a postnuptial pattern of spermatogenesis typical of temperate‐zone turtles elsewhere, with a peak in spermatogenic activity in autumn and a cessation of activity during the breeding season in spring and early summer. The spermatogenic cycle is paralleled by seasonal variation in testicular weight (standardized for body size) and in the diameter of the seminiferous tubules. Sperm are abundant in the epididymal canals throughout the year. Mating was observed in autumn, late winter and spring.Females have a cyclic reproductive pattern, with distinct phases of follicular enlargement, ovulation and oviducal period, and quiescence. Yolk begins to accumulate in the ovaries in late summer, and the accumulation continues unabated through the winter, presumably by the transfer of material from fat stores to the ovaries. Ovulations occur from late winter to mid‐summer. Atresia of follicles that fail to ovulate was demonstrated histologically. Emydura krefftii lay up to three clutches of hard‐shelled ellipsoid eggs per season. Each clutch contains between four and 10 eggs; the number is strongly correlated with maternal body size. Reproductive potential ranges from 12 eggs per annum for a female that has recently matured (carapace length c. 150 mm), to 30 eggs per annum for a full‐sized female (length c. 250 mm). Selected life‐history traits of Emydura krefftii are discussed in the context of findings for other populations of the species and for other species of freshwater turtle.
Spring dispersal and agonistic behaviour of the Red‐legged partridge (Alectoris rufa)
Authors: Green R. E. 
Published: August 2009

Spring behaviour, dispersal and population changes were studied in two populations of individually marked Red‐legged partridges.Young males took up home ranges close to their natal site but young females dispersed away. The incidence of agonistic behaviour between males, the extent of the spring decline in population density and the distance dispersed by males between the winter and breeding ranges were less in an area with more abundant nesting cover.Half the neighbours of a typical male came from the same winter social group. These groups were based on family parties. Males from the same winter group showed less frequent agonistic behaviour to each other and had more overlapped home ranges than those from different groups.
The annual cycle of the testis of the elephant seal (Mirounga leonina) at Macquarie Island
Authors: Griffiths D. J. 
Published: August 2009

The testis of the Southern elephant seal demonstrates seasonal changes in weight, with highest values early in the breeding season (September‐November) and lowest values in mid‐winter (May‐June). Weight changes originate in the seminiferous tubules, there being little variation in the interstitial tissue.Spermatogenesis begins in August, one month before the breeding season, and stops in November. Testicular testosterone concentration is significantly elevated in the months July‐September. Plasma testosterone concentration is high only in September, the first month of breeding.
Aspects of the reproductive endocrinology of the female Giant panda (Ailuropoda metanoleaca) in captivity with special reference to the detection of ovulation and pregnancy
Authors: Hodges J. K. , Bevan D. J. , Celma M. , Hearn J. P. , Jones D. M. , Kleiman D. G. , Knight J. A. , Moore H. D. M. 
Published: August 2009

The metabolism and pattern of excretion of urinary steroids during oestrus and pregnancy in the Giant panda is described. Three female pandas from the London, Washington and Madrid Zoos were studied over different periods between March 1980 and September 1982.High pressure liquid chromatography and sequential enzyme hydrolysis indicated that oestrone glucuronide was the most abundant urinary oestrogen metabolite during oestrus. Levels of conjugated oestrone in late pregnancy, however, were low and similar to those of conjugated oestradiol‐17βThere was a rapid increase in the excretion of conjugated oestrone to reach maximum levels during late pro‐oestrus; oestrus occurred when levels of conjugated oestrone were declining. The measurement of oestrone‐3‐glucuronide by direct, non‐extraction assay provides a rapid and reliable method for detecting oestrus and ovulation in the Giant panda.Artificial insemination of the London and Madrid pandas was performed in 1981 and 1982, respectively. The Madrid panda gave birth to twin cubs after a gestation period of 159 days. Levels of urinary oestrone conjugate remained low throughout pregnancy. There was no increase in the excretion of pregnanediol‐3α‐glucuronide (assumed to be an urinary metabolite of progesterone) until approximately day 120 when a rapid, five‐fold increase in levels occurred. The levels of pregnanediol‐3α‐glucuronide remained elevated for approximately three weeks after which there was a gradual decline beginning two‐and‐α‐half weeks before parturition. Measurement of pregnanediol‐3α‐glucuronide enables the detection of pregnancy after three to four months and should also be useful in predicting parturition. A delay of implantation during pregnancy in the Giant panda is suggested.There was no consistent elevation in pregnanedioI‐3α‐glucuronide excretion in the five months after artificial insemination of the London panda, despite a marked increase in circulating progesterone of ovarian origin. Pregnancy could not be confirmed from external examination of the uterus at laparotomy; histological examination of biopsy material revealed advanced endometrial hyperplasia.
Hindlimb muscle activity during locomotion in the rat (Rattus norvegicus) (Rodentia: Muridae)
Authors: Nicolopoulos‐Stournaras S. , Iles J. F. 
Published: August 2009

Electromyographic studies of mammalian locomotion have concentrated on cursorial species. Since these may not be typical of mammals in general, the present study has been made on the relatively non‐cursorial rat.Electromyography has been performed on 20 muscles or muscle groups of the hind‐limb in decerebrate rats, moving at from one to eight steps per second. All muscles were active in discrete bursts, with fixed phase relations in the step cycle. They can be categorized as flexors–active just before and during swing, extensors/adductors–active just before and during stance, muscles controlling the foot, and some double joint muscles. The latter, represented by semitendinosus and rectus femoris, tend to be active twice in each step cycle. There is a distinct reciprocity in the activities of these two muscles. The duration of the extensor/adductor activity decreases with increase of stepping speed.The pattern of muscle activity during the step cycle is very similar in both cursorial species and the rat. This suggests that central nervous mechanisms controlling the timing of single limb motor output in mammals may be very conservative.
The functional anatomy of the foregut of Porcetlana platychetes and a comparison with Galathea squamifera and Upogebia deltaura (Crustacea: Decapoda)
Authors: Ngoc‐Ho Nguyen 
Published: August 2009

Muscles, ossicles and internal structures of the foregut of Porcellana platycheles are described and figured. The function of the foregut is deduced from the distribution of food particle size within its chambers. The trough of the cardio‐pyloric valve is considered to be the main site of digestion and the supra‐ampullary valve to have an active role in the formation of the ventral cap of faecal pellets.The structures and function of the foregut of Galathea squamifera are similar to those of P. platycheles. Certain differences found in the foregut of Upogebia deltaura may be related to the small size of food particles ingested and the absence of a ventral cap from faecal pellets may be due to the supra‐ampullary valve having no action on surrounding particles.
Pollen‐feeding in thrips (Insecta: Thysanoptera)
Authors: Kirk W. D. J. 
Published: August 2009

Eight species of thrips in three families fed readily on individual grains of pollen. Feeding behaviour is described. Thrips fed on the contents of the grains, but left the pollen wall. In Thrips fuscipennis Halid., the feeding time per grain increased in direct proportion to grain volume up to a grain volume of about 60,000 μm'. but then began to level off. Large grains and tetrads were usually abandoned before all the contents were removed. Mean feeding times ranged from 3 s to 120 s per grain.Thrips appeared to have alternate periods of feeding and non‐feeding. Drops of fluid were sometimes deposited from the end of the abdomen after non‐feeding periods. Large amounts of pollen can be consumed; one thrips fed on more than 100 pollen grains in less than 15 min. Pollen‐feeding appears to be widespread among flower thrips. The implications for pollination ecology are discussed.
Site selection and attachment duration of Anodonta woodiana (Bivalvia: Unionacea) glochidia on fish hosts
Authors: Dudgeon D. , Morton B. 
Published: August 2009

The relationship between parasitic glochidia of Anodonia woodiana (Unionidae: Anodonti‐nae) and potential fish hosts was investigated in the laboratory. Intensity of parasitism was highest on the exotic fish Gambusia affinis, lower on the native species Puntius semijascio‐latus and Metzia takakii, and least on Rhodeus sinensis. Glochidia generally attached at fin margins, particularly the pectorals and caudal. In Gambusia affinis, the incidence of glochidia on the pectorals was higher than would be expected on the basis of ratios between fin margin lengths. Apparently, the role of the pectoral fins in locomotion makes them more liable to glochidial contact, thereby increasing their susceptibility to attachment.The duration of glochidial attachment was shortened as temperatures increased. Mean values ranged from 14‐4 days at 15°C to 6 days at 27°C. At 33°C glochidia rapidly detached and metamorphosis was unsuccessful. Significantly, water temperatures in A. woodiana habitats in Hong Kong rarely exceed 30°C.
The functional morphology of Sinonovacula constricta with a discussion on the taxonomic status of the Novaculininae (Bivalvia).
Authors: Morton Brian 
Published: August 2009

Sinonovacula constricta is representative of two genera of deep burrowing bivalves hitherto placed in the Novaculininae of the Tellinacea. This species, widely cultured in China, has not previously been critically examined. Aspects of its anatomy show that it should more properly be placed in the Solenacea. The presently accepted classification of this superfamily suggests that it should be placed close to Pharella in the Cultellidae but it is clear that the group requires more detailed re‐examination.Sinonovacula is somewhat posteriorly elongate with long separate siphons. The anterior pedal gape acts as a valve to the piston‐like foot enabling rapid reburrowing to occur. Sensory tentacles around the pedal gape respond to mechanical disturbance and water can be squirted from the gape to, presumably, flush away the source of irritation. Modifications of this kind are rare in the Bivalvia.The anatomy of Sinonovacula is described and related to its life style as a suspension feeder in soft intertidal muds. The ciliary currents of the mantle cavity are powerful, the labial palps in particular being large as compared with the relatively small ctenidia. The stomach is adapted for dealing with large amounts of food, though the sorting areas are not extensive; principal sorting is clearly the function of the labial palps. The style sac and mid‐gut are separate (unlike the conjoined style sac and mid gut of the Tellinacea), and ensure separation of the style from the sediment loaded mid gut.In many ways Sinonovacula foreshadows the highly modified true razor shells and conditions in these bivalves can be accounted for by further posterior elongation of a bivalve essentially similar to Sinonovacula.
Tumor necrosis factor‐alpha inhibits Schwann cell proliferation by up‐regulating Src‐suppressed protein kinase C substrate expression
Authors: Tao Tao , Ji Yuhong , Cheng Chun , Yang Huiguang , Liu Haiou , Sun Linlin , Qin Yongwei , Yang Junling , Wang Huiming , Shen Aiguo 
Published: August 2009

AbstractSrc‐suppressed protein kinase C substrate (SSeCKS) is a protein kinase C substrate protein, which plays an important role in mitogenic regulatory activity. In the early stage of nerve injury, expression of SSeCKS in the PNS increases, mainly in Schwann cells (SCs). However, the exact function of SSeCKS in the regulation of SC proliferation remains unclear. In this study, we found that tumor necrosis factor‐alpha (TNF‐α) induced both SSeCKS α isoform expression and SC growth arrest in a dose‐dependent manner. By knocking down SSeCKS α isoform expression, TNF‐α‐induced growth arrest in SCs was partially rescued. Concurrently, the expression of cyclin D1 was reduced and the activity of extracellular signal‐regulated kinase 1/2 was decreased. A luciferase activity assay showed that cyclin D1 expression was regulated by SSeCKS at the transcription level. In addition, the cell fragments assay and immunofluorescence revealed that TNF‐α prevented the translocation of cyclin D1 into the nucleus, while knocking down SSeCKS α isoform expression prompted cyclin D1 redistribution to the nucleus. In summary, our data indicate that SSeCKS may play a critical role in TNF‐α‐induced SC growth arrest through inhibition of cyclin D1 expression thus preventing its nuclear translocation.
Induction of Nrf2 and xCT are involved in the action of the neuroprotective antibiotic ceftriaxonein vitro
Authors: Lewerenz Jan , Albrecht Philipp , Tien Mai‐Ly Tran , Henke Nadine , Karumbayaram Saravanan , Kornblum Harley I. , Wiedau‐Pazos Martina , Schubert Dave , Maher Pamela , Methner Axel 
Published: August 2009

AbstractIn amyotrophic lateral sclerosis, down‐regulation of the astrocyte‐specific glutamate excitatory amino acid transporter 2 is hypothesized to increase extracellular glutamate, thereby leading to excitotoxic motor neuron death. The antibiotic ceftriaxone was recently reported to induce excitatory amino acid transporter 2 and to prolong the survival of mutant superoxide dismutase 1 transgenic mice. Here we show that ceftriaxone also protects fibroblasts and the hippocampal cell line HT22, which are not sensitive to excitotoxicity, against oxidative glutamate toxicity, where extracellular glutamate blocks cystine import via the glutamate/cystine‐antiporter system xc−. Lack of intracellular cystine leads to glutathione depletion and cell death because of oxidative stress. Ceftriaxone increased system xc−and glutathione levels independently of its effect on excitatory amino acid transporters by induction of the transcription factor Nrf2 (nuclear factor erythroid 2‐related factor 2), a known inducer of system xc−, and the specific xc−subunit xCT. No significant effect was apparent in fibroblasts deficient in Nrf2 or xCT. Similar ceftriaxone‐stimulated changes in Nrf2, system xc−, and glutathione were observed in rat cortical and spinal astrocytes. In addition, ceftriaxone induced xCT mRNA expression in stem cell‐derived human motor neurons. We conclude that ceftriaxone‐mediated neuroprotection might relate more strongly to activation of the antioxidant defense system including Nrf2 and system xc−than to excitatory amino acid transporter induction.
Caffeine consumption attenuates neurochemical modifications in the hippocampus of streptozotocin‐induced diabetic rats
Authors: Duarte João M. N. , Carvalho Rui A. , Cunha Rodrigo A. , Gruetter Rolf 
Published: August 2009

AbstractType 1 diabetes can affect hippocampal function triggering cognitive impairment through unknown mechanisms. Caffeine consumption prevents hippocampal degeneration and memory dysfunction upon different insults and is also known to affect peripheral glucose metabolism. Thus we now characterized glucose transport and the neurochemical profile in the hippocampus of streptozotocin‐induced diabetic rats usingin vivo1H NMR spectroscopy and tested the effect of caffeine consumption thereupon. We found that hippocampal glucose content and transport were unaltered in diabetic rats, irrespective of caffeine consumption. However diabetic rats displayed alterations in their hippocampal neurochemical profile, which were normalized upon restoration of normoglycaemia, with the exception ofmyo‐inositol that remained increased (36 ± 5%,p < 0.01 compared to controls) likely reflecting osmolarity deregulation. Compared to controls, caffeine‐consuming diabetic rats displayed increased hippocampal levels ofmyo‐inositol (15 ± 5%,p < 0.05) and taurine (23 ± 4%,p < 0.01), supporting the ability of caffeine to control osmoregulation. Compared to controls, the hippocampus of diabetic rats displayed a reduced density of synaptic proteins syntaxin, synaptophysin and synaptosome‐associated protein of 25 kDa (in average 18 ± 1%,p < 0.05) as well increased glial fibrillary acidic protein (20 ± 5%,p < 0.05), suggesting synaptic degeneration and astrogliosis, which were prevented by caffeine consumption. In conclusion, neurochemical alterations in the hippocampus of diabetic rats are not related to defects of glucose transport but likely reflect osmoregulatory adaptations caused by hyperglycemia. Furthermore, caffeine consumption affected this neurochemical adaptation to high glucose levels, which may contribute to its potential neuroprotective effects, namely preventing synaptic degeneration and astrogliosis.
The role of fruit traits of bird‐dispersed plants in invasiveness and weed risk assessment
Authors: Gosper Carl R. , Vivian‐Smith Gabrielle 
Published: August 2009

AbstractAim  Birds play a major role in the dispersal of seeds of many fleshy‐fruited invasive plants. The fruits that birds choose to consume are influenced by fruit traits. However, little is known of how the traits of invasive plant fruits contribute to invasiveness or to their use by frugivores. We aim to gain a greater understanding of these relationships to improve invasive plant management.Location  South‐east Queensland, Australia.Methods  We measure a variety of fruit morphology, pulp nutrient and phenology traits of a suite of bird‐dispersed alien plants. Frugivore richness of these aliens was derived from the literature. Using regressions and multivariate methods, we investigate relationships between fruit traits, frugivore richness and invasiveness.Results  Plant invasiveness was negatively correlated to fruit size, and all highly invasive species had quite similar fruit morphology [smaller fruits, seeds of intermediate size and few (< 10) seeds per fruit]. Lower pulp water was the only pulp nutrient trait associated with invasiveness. There were strong positive relationships between the diversity of bird frugivores and plant invasiveness, and in the diversity of bird frugivores in the study region and another part of the plants’ alien range.Main conclusions  Our results suggest that weed risk assessments (WRA) and predictions of invasive success for bird‐dispersed plants can be improved. Scoring criteria for WRA regarding fruit size would need to be system‐specific, depending on the fruit‐processing capabilities of local frugivores. Frugivore richness could be quantified in the plant’s natural range, its invasive range elsewhere, or predictions made based on functionally similar fruits.