bluuebunny/crossref_metadata_2025 huggingface dataset:
Academic Procrastination in Two Settings: Motivation Correlates, Behavioral Patterns, and Negative Impact of Procrastination in Canada and Singapore
Authors: Klassen Robert M. , Ang Rebecca P. , Chong Wan Har , Krawchuk Lindsey L. , Huan Vivien S. , Wong Isabella Y.F. , Yeo Lay See
Published: May 2009

Two studies are reported examining academic procrastination and motivation in 1,145 university students from Canada and Singapore. In Study 1, relationships between procrastination and motivation variables were found to be similar across contexts, with self‐efficacy for self‐regulated learning most strongly associated with procrastination in both contexts. In Study 2, patterns of procrastinating behavior and the negative impact of procrastination were examined and compared in Canadian and Singaporean undergraduates. Participants in both contexts reported writing to be the academic task most prone to procrastination. More Singaporeans than Canadians were classified as negative procrastinators (i.e. rated procrastination as a negative influence on academic functioning). In both contexts, negative procrastinators spent more time procrastinating than neutral procrastinators and displayed lower self‐efficacy for self‐regulated learning.

On décrit deux recherches portant sur la motivation et la procrastination universitaire (tendance à remettre au lendemain) de 1145 étudiants du Canada et de Singapour. Dans la première étude, les relations entre la motivation et la procrastination sont apparues être analogues dans les deux pays, la variable la plus fortement associéà la procrastination étant l'auto‐efficience pour l'apprentissage autorégulé. Dans la deuxième étude, les schémas comportementaux de procrastination et son impact négatif ont été analysés et comparés chez les étudiants de 1° cycle canadiens et singapouriens. Les sujets des deux pays ont mentionné la rédaction comme étant la tâche universitaire la plus soumise à la procrastination. Davantage de Singapouriens que de Canadiens été classés en procrastinateurs négatifs (c'est‐à‐dire que la procrastination est considérée comme étant un handicap pour les études). Dans les deux cas, les procrastinateurs négatifs gaspillaient plus de temps que les procrastinateurs neutres et manifestaient une moindre auto‐efficience pour l'apprentissage autorégulé.
The experience of puberty in adolescent boys: an Iranian perspective
Authors: Ahmadi F. , Anoosheh M. , Vaismoradi M. , Safdari M.‐T.
Published: May 2009

Background:  The process of puberty is a normal physiological event for adolescents. Studies show that there is not enough knowledge about boys' puberty experiences. In spite of physiological similarities of puberty characteristics in different societies, social, cultural and religious factors have an important influence on puberty process.

Aim:  To begin to explore the experiences of adolescents and parents about puberty within the Iranian cultural context.

Methods:  Qualitative research was adopted using thematic analysis of semi‐structured interviews carried out with 16 adolescent boys (13–17 years old) and 12 parents. All studies were transcribed verbatim and analysed.

Findings:  The analysis of the transcripts showed four main themes including shame and embarrassment, anxiety, transition, puberty orientation and management.

Conclusion:  Development of knowledge about puberty issues is important; additionally meeting health and educational needs of this transient period is one of the main priorities of the healthcare system and society. Knowledge of puberty is important for nurses and counsellors who work with adolescents for planning primary prevention programmes related to sexual health education and adolescent mental health.

Limitations:  Boy's embarrassment about describing puberty changes was a hindrance to their full engagement in the interviews; therefore in some situations the interviews were not as deep as was wished. This limitation is related to the subject itself, not the method used for data gathering.
Turkish nurses' perspectives on a programme to reduce burnout
Authors: Günüşen N.P. , Üstün B.
Published: May 2009

Background:  Burnout is a serious problem among nurses. Programmes to prevent and reduce burnout have been described, but nurses report that they have difficulty attending such programmes and the dropout rate is substantial.

Aim:  To investigate the perspectives of nurses on burnout and the barriers and facilitators affecting attendance at a burnout reduction programme offered in their institution.

Methods:  A qualitative study using semi‐structured interviews was conducted with 18 nurses who had volunteered to attend a burnout intervention programme at a University Hospital in Izmir, Turkey. Six of the nurses had not attended any sessions, six attended four or less of the seven and six attended all sessions. Data were analysed using thematic analysis.

Results:  Nurses attributed burnout to their heavy workload and a lack of recognition for their work. Most stated that they need work‐directed rather than person‐directed interventions to reduce stress and burnout. Attendance at the intervention programme was impeded by such issues as a perceived lack of institution support and the possibility of being seen by other nurses as unable to cope with stress.

Conclusion:  Researchers planning burnout intervention programmes should consider ways of increasing cooperation between the administration and the staff that facilitate attendance at such programmes. A holistic approach involving work‐directed and person‐directed interventions is recommended.
Institutional Reforms and Investor Reactions to CSR Announcements: Evidence from an Emerging Economy
Authors: Arya Bindu , Zhang Gaiyan
Published: May 2009

abstract

This study contributes to the limited established empirical research on the impact and relevance of corporate social responsibility (CSR) in the capital markets of emerging economies. We conducted an event study to demonstrate how the timing of CSR announcements by firms that have aligned their strategies to newly instituted social regulations in South Africa influenced stock prices. Using a unique dataset of publicly listed South African enterprises that undertook CSR initiatives during the ten year period from 1996 to 2005, we found that investor reactions to CSR announcements concluded during the late phase of institutional reforms are viewed positively by investors. Furthermore, CSR announcements of substantive monetary value result in significantly higher shareholder returns.
Stimulating Strategically Aligned Behaviour Among Employees
Authors: Van Riel Cees B. M. , Berens Guido , Dijkstra Majorie
Published: May 2009

abstract

Strategically aligned behaviour (SAB), i.e. employee action that is consistent with the company's strategy, is of vital importance to companies. This study provides insights into the way managers could promote such behaviour among employees (who can be managers as well) by stimulating employee motivation, by informing employees, and by stimulating the development of their capabilities. The results of surveys conducted in three organizations suggest that, first, perceived efforts by management aimed at motivating and informing employees (both managers and non‐managers), and at developing their capabilities, each are related to SAB. Second, among the perceived efforts to stimulate motivation among employees, providing a rationale for the strategy and an open communication climate have a stronger relationship with SAB than participation in decision making and supportiveness. Third, the perceptions of the different types of managerial effort are related to each other. For this reason, the efforts have direct as well as indirect relationships to SAB. Fourth, each of the perceived efforts seems to be complementary to the others, in the sense that the relationship of one type of effort to SAB is stronger when other types of effort are perceived to be higher.
Regrets in the East and West: Role of intrapersonal versus interpersonal norms
Authors: Hur Taekyun , Roese Neal J. , Namkoong Jae‐Eun
Published: May 2009

Regrets are stronger following atypical than following normal behaviour. No studies have tested this effect for both intrapersonal normality (consistency within a person) and interpersonal normality (consistency between people) simultaneously. The present research examined whether the impact of violating the two kinds of normality on regret varies across cultures, using a manipulation of mutability crossed with that of norm violation. Among Korean participants (but not Americans) the impacts of mutability on regret were stronger when the intrapersonal rather than the interpersonal norm was violated, which was interpreted in terms of the greater collectivist emphasis in Korea than in the USA.
Union Organizing as a Mobilizing Strategy: The Impact of Social Identity and Transformational Leadership on the Collectivism of Union Members
Authors: Cregan Christina , Bartram Timothy , Stanton Pauline
Published: May 2009

This article investigates the effect of union organizing as a mobilizing strategy on the collectivism of union members. We examine the impact of a worker's social identification with fellow members and the transformational leadership qualities of the local union representative. We employ regression analysis with tests of mediation to analyse the survey responses of c. 1,000 rank and file members of a major professional union, collected in July 2004 during a mobilization campaign. Social identification and transformational leadership were associated with members' union loyalty and willingness to work for the union. Social identification acted as a mediating variable in both cases.
Court Finance and Court Responses to Judicial Reforms: A Tale of Two Chinese Courts
Authors: HE XIN
Published: May 2009

This research studies the responses of two lower‐level courts, one in rural and the other in urban China, to recent judicial reforms focusing on strengthening institutional building and professionalism. It finds that the court‐funding structure under which the courts heavily rely on the local government for expenses, together with the unbalanced development of local economy, remarkably affects the two courts' behavioral pattern in different ways. The rural court, for the sake of litigation fees, tries to attract potential litigants to file certain lawsuits, even though it cannot effectively handle them. The efforts toward institutional building and professionalism only aggravate the already difficult situation. The urban court's institutional quality seems to have increased in the reform process, thanks to sufficient resources from the developed and diversified local economy. But it has also become more formalized and bureaucratic, as it tries to exclude difficult and problematic disputes from getting into the court. In illustrating the complexity of transitional China's judicial reform process generated by both the unbalanced economic development and the bureaucratization of the judiciary, this article suggests that the enhancement of institutional quality, which many argue is key to economic development, may itself be contingent upon the success of economic development.
Automatic tuning of L2‐SVM parameters employing the extended Kalman filter
Authors: Mu Tingting , Nandi Asoke K.
Published: May 2009

Abstract: We show that tuning of multiple parameters for a 2‐norm support vector machine (L2‐SVM) could be viewed as an identification problem of a nonlinear dynamic system. Benefiting from the reachable smooth nonlinearity of an L2‐SVM, we propose to employ the extended Kalman filter to tune the kernel and regularization parameters automatically for the L2‐SVM. The proposed method is validated using three public benchmark data sets and compared with the gradient descent approach as well as the genetic algorithm in measures of classification accuracy and computing time. Experimental results demonstrate the effectiveness of the proposed method in higher classification accuracies, faster training speed and less sensitivity to the initial settings.
Estimating the uniaxial compressive strength of some clay‐bearing rocks selected from Turkey by nonlinear multivariable regression and rule‐based fuzzy models
Authors: Gokceoglu C. , Sonmez H. , Zorlu K.
Published: May 2009

Abstract: Although the use of predictive models in rock engineering and engineering geology is an important issue, some simple and multivariate regression techniques traditionally employed in these areas have recently been challenged by the use of fuzzy inference systems and artificial neural networks. The purpose of this study was to construct some predictive models to estimate the uniaxial compressive strength of some clay‐bearing rocks, depending on examination of their slake durability indices and clay contents. For this purpose, the simple and nonlinear multivariable regression techniques and the Mamdani fuzzy algorithm are compared in terms of their accuracy. To increase the accuracy of the Mamdani fuzzy inference system, the weighted if–then rules are extracted. To compare the predictive performances of the models, the statistical performance indices (root mean square error and variance account for) are calculated and the results are discussed. The indices reveal that the fuzzy inference system has a slightly higher prediction capacity than the regression models. The basic reason for the higher performance of the fuzzy inference system is the flexibility of the fuzzy approach.
Tenofovir disoproxil fumarate in pregnancy and prevention of mother‐to‐child transmission of HIV‐1: is it time to move on from zidovudine?
Authors: Foster C , Lyall H , Olmscheid B , Pearce G , Zhang S , Gibb DM
Published: May 2009

Objectives
Zidovudine (ZDV) has been the cornerstone of antiretroviral (ARV) therapy for pregnant women infected with HIV‐1 in the prevention of mother‐to‐child transmission (MTCT) and remains the only licensed ARV for use in pregnancy. We explored the current and future roles of tenofovir disoproxil fumarate (TDF) in the prevention of MTCT of HIV‐1.

Methods
We reviewed the published literature by conducting database searches of in vitro, animal and clinical studies, reported in journals and at conferences, using the search terms Tenofovir/gs4331/viread, pregnant/pregnancy, lactate, lactation, natal, reproduce/reproduction, placenta/placental, malformation, and teratogenicity/teratogenic.

Results
In a macaque model, perinatal exposure to very high dose tenofovir resulted in bone toxicity in some offspring. However, perinatal use of TDF, both single dose and as part of highly active antiretroviral therapy in women, has been well tolerated in the short term by mothers and their infants. Further, the addition of single‐dose TDF to single‐dose nevirapine (SD‐NVP) during delivery following maternal ZDV use during pregnancy significantly reduces the frequency of nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance.

Conclusions
The addition of TDF to SD‐NVP reduces NNRTI resistance. The role of TDF in this setting and during pregnancy for reducing rates of MTCT requires investigation. While short‐term toxicity data are encouraging, long‐term follow‐up of exposed mothers and infants is required.
Perception of stroke in Croatia – knowledge of stroke signs and risk factors amongst neurological outpatients
Authors: Vuković V. , Mikula I. , Kesić M. J. , Bedeković M. R. , Morović S. , Lovrenčić‐Huzjan A. , Demarin V.
Published: May 2009

Background and purpose:  The aim of this hospital‐based survey was to determine baseline stroke knowledge in Croatian population attending the outpatient services at the Department of Neurology.

Methods:  A multiple choice questionnaire was designed, divided into three sections: (i) demographic data, (ii) knowledge of stroke risk factors and stroke signs and (iii) actions the patients would undertake if confronted with risk of stroke and information resources regarding health.

Results:  The analysis included 720 respondents (54.9% women). The respondents most frequently indicated stroke symptoms as following: speech disorder 82%, paresthesiae on one side of the body 71%, weakness of arm or leg 55%, unsteady gait 55%, malaise 53%, monocular loss of vision 44%. The risk factors most frequently identified were hypertension 64%, stress 61%, smoking 59%, elevated lipids 53%, obesity 52%, coagulation disorder 47%, alcoholism 45%, low‐physical activity 42%, elderly age 39%, cardiac diseases 38%, weather changes 34%, drugs 33% and diabetes 32%. If confronted with stroke signs 37% of respondents would consult the general practitioner and 31% would call 911 or go to a neurologist. Amongst patients with a risk factor, only diabetics were aware that their risk factor might cause stroke (P < 0.001). Respondents with lowest education had the least knowledge regarding stroke signs (P < 0.01).

Discussion:  The results of this study indicate that respondents showed a fair knowledge about stroke signs and risk factors for stroke. The results of our study will help to create and plan programmes for improvement of public health in Croatia.
Measurements of gas permeability and diffusivity of tight reservoir rocks: different approaches and their applications
Authors: CUI X. , BUSTIN A. M. M. , BUSTIN R. M.
Published: May 2009

Permeability and diffusivity are critical parameters of tight reservoir rocks that determine their viability for commercial development. Current methods for measuring permeability and/or diffusivity may lead to erroneous results when applied to very tight rocks including gas shales, coal, and tight gas sands, as well as rocks considered as seals for nuclear waste repositories and strata for geological sequestration of CO2. The use of He as routinely applied to measure porosity, permeability, and diffusivity may result in non‐systematic errors because of the molecular sieving effect of the fine pore structure to larger molecules such as reservoir gases. Utilizing gases with larger adsorption potentials than He, such as N2, and including all reservoir gases to measure porosity or permeability of rocks with high surface area is a viable alternative, but requires correcting for adsorption in the analyses. This study expands several approaches to measure permeability and diffusivity with considerations for gas adsorption, which has not been explicitly considered in previous studies. We present new models that explicitly correct for adsorption during pulse‐decay measurements of core under reservoir conditions, as well as on crushed samples used to approximate permeability or diffusivity. We also present a method to determine permeability or diffusivity from on‐site drill‐core desorption test data as carried out to determine gas in place in coals or gas shales. Our new approach utilizes late‐time data from experimental pressure‐decay tests, which we show to be more reliable and theoretically (and practically) accurate than the early‐time approach commonly used to estimate gas‐transport properties.
Heterogeneous expression of suppressor of cytokine signalling 2 (SOCS‐2) in liver tissue
Authors: Zellmer Sebastian , Sickinger Stephan , Schmidt‐Heck Wolfgang , Guthke Reinhard , Gebhardt Rolf
Published: May 2009

Suppressor of cytokine signalling 2 (SOCS‐2), a dual effector of growth hormone signalling, was found to be heterogeneously expressed in murine liver parenchyma. Data from Affymetrix gene arrays, confirmed by quantitative RT‐PCR using preparations of periportal and pericentral hepatocyte subpopulations as well as immunohistochemical detection, showed a preferential expression of SOCS‐2 in pericentral hepatocytes. Stimulation of cultured periportal and pericentral hepatocyte subpopulations by different concentrations of growth hormone for 1 h resulted at 100 ng mL−1in a 1.6‐fold and 4.3‐fold increase of SOCS‐2 mRNA, respectively. Likewise, insulin‐like growth factor‐1, another physiological target of growth hormone, was stimulated preferentially in pericentral hepatocytes. As growth hormone receptor was found to be homogeneously expressed in mouse liver parenchyma, our data indicate that growth hormone signalling downstream of growth hormone receptor is more sensitive and/or effective in pericentral than in periportal hepatocytes. Presumably, the heterogeneous distribution of SOCS‐2 may contribute to the pericentral preference of growth hormone action via differential feedback.
Water and sodium fluxes and lactational energetics in suckling pups of Weddell seals (Leptonychotes weddellii)
Authors: Tedman R. , Green B.
Published: May 2009

Estimates of the water and sodium fluxes of unrestrained Weddell seal pups were derived from the turnover of tritiated water and 22sodium chloride throughout the nursing period. Milk intake was calculated from water influx. There was a strong correlation between daily body weight gain in pups (x̄= 1·98 ± 0·44 kg/d) and daily weight loss by dams (x̄= 4·55±1·24 kg/d; r= 0·85, p <0·001). The maximum weight loss recorded was 249 kg over 38 days. This considerable drain on the dams' energy reserves amounts to a loss of almost 60 % of the female's body weight after parturition. Mean total body water of pups decreased from 72·5 % at birth to 48·6 % at day 40 of lactation.

Total milk consumption was positively correlated with body weight gain by pups (r= 0·87, p < 0.001), with daily milk intake ranging from 2·76 to 5·46 1/day (x̄= 3.54 ± 0·87 1/d). The pups gained 0·51 ± 0·08 kg body weight for each litre of milk consumed, and the efficiency of conversion of milk energy to stored energy was 52·1 ± 7·7 %.

Sodium influx rates averaged 2±24 · 0±41 mmol/kg. day. Approximately 70% of sodium intake was derived from milk, with the remainder coming from the ingestion of small amounts of sea water.

The high energy content of the milk (20·8 MJ/kg) and reduced milk yield (relative to body weight) means that pups can consume sufficient energy for rapid growth with comparatively brief nursing periods and short lactational duration. The relatively longer duration of lactation in the Weddell seal, during which the dams and pups engage in extensive swimming activities, has resulted in: (a) reduced daily energy intake by pups, and (b) increased percentage weight loss by dams compared to other phocids.
The feeding ecology of mink (Mustela vison) in coastal habitat
Authors: Dunstone N. , Birks J. D. S.
Published: May 2009

The diet of a coast‐living population of mink was investigated from the scats collected over a three‐year period, and compared with information on the availability of principal prey species. Lagomorphs were the single most important prey, and predation upon them matched the abundance of rabbits as determined by monthly counts. Aquatic foraging was particularly important, with rockpool‐inhabiting fish accounting for 29–1% occurrence of food items. Fish predation was more pronounced during winter months when lagomorph prey was less available. Crustacean prey, particularly the shore crab, Carcinus maenas, occurred frequently in the diet. Seabirds figured regularly in the diet; these were either taken as carrion from the strand‐line or through predation on breeding colonies during the summer months.
Sperm‐storage glands in a passerine: the zebra finch Poephila guttata (Estrildidae)
Authors: Birkhead T. R.
Published: May 2009

Sperm‐storage glands in the zebra finch are described; the first passerine for which such information is available. Sperm‐storage glands occurred only in paired females, and were located in folds throughout the vagina and on the vaginal side of the utcro‐vaginal region. Mean dimensions of the glands were: internal diameter 17·5 μm and length 254 μm; these values are similar to those found for two other (much larger) bird species. The need for passerines to possess sperm‐storage glands is discussed.
Paracloacal glands of Alligator mississippiensis: A histological and histochemical study
Authors: Weldon Paul J. , Sampson H. Wayne
Published: May 2009

The histology of the paracloacal ‘musk’ glands of adult American alligators (Alligator mississippiensis) is described. The gland is a single secretory sac with a single duct and a central lumen partially occluded by a central, cylindrical conglomerate of cells and secretion product. The capsule of the gland consists of an outer layer of smooth muscle and an inner layer of connective tissue containing collagen and elastin fibres. Septa carrying blood vessels radiate from the connective tissue layer of the capsule to the border of the central conglomerate. Parenchymal cells containing lipid droplets enlarge from the periphery to the centre of the gland. Secretions formed by degeneration of cells in the central cylinder are concentrated near the secretory duct. Histochemical tests indicate lipids but not mucopolysaccharides in the glandular exudate.
Extra‐pair paternity in the shag, Phalacrocorax aristotelis as determined by DNA fingerprinting
Authors: Graves J. , Hay R. T. , Scallan M. , Rowe S.
Published: May 2009

The frequency of chicks resulting from extra‐pair copulation in the shag, Phalacrocorax aristotelis, was measured by DNA fingerprinting. DNA fingerprints were taken from both sexes of 15 pairs and their chicks (28) in a subcolony on the Isle of May, UK. It was found that 18% of the chicks had extra‐pair paternity, and one chick (3.5%) was not the offspring of either member of the pair, implying either a polygynous male whose second female was fertilized by another male or adoption. Although no observations of courtship and copulation were made in the same season, observations in a previous year on the same colony of shags showed that 14.1% of the copulations by males were not with the female with whom that male reared young. The similarities and differences are discussed between these results on the level of extra‐pair copulations and of extra‐pair paternity and those of other studies where both observations of extra‐pair copulations and various measures of the degree of extra‐pair paternity have been made.
Relationships among allozyme heterozygosity, morphology and lipid levels in house sparrows during winter
Authors: Fleischer R. C. , Murphy M. T.
Published: May 2009

House sparrows (Passer domesticus) were collected during cold (43 individuals) and warm (31 individuals) periods in February 1982 from farms near Lawrence, Kansas. Fat scores (from flank, rump and furcula) and body mass were measured from the carcasses, which were then reduced to skeletons. Heterozygosity was determined by electrophoresis of three polymorphic allozymes. Pectoral lipid content was determined by petroleum ether extraction. Principal component (PC) analysis was conducted on 14 skeletal measurements. Summed fat score, body mass and pectoral lipid content served as dependent variables in three multiple regressions. Sex, period (cold versus warm), number of heterozygous loci (0–3), and scores of PCI, PC2 and PC3 were independent variables. Each of the dependent variables was also included as an independent variable in regressions in which they were not the dependent variable. Pectoral lipid content was significantly related only to the number of heterozygous loci (R2= 0.18,P= 0.008). Summed fat score differed between sexes and periods (P= 0.012 and 0.001, respectively) when body mass was included in the regression (P< 0 001). Body mass was related to summed fat score as above, and also to body size (PCI,P< 0.0001) and period (P= 0.014). Females exhibited a positive regression between body size and summed fat score (P= 0.007). Body size (PCI) was greater for both sexes in the sample from the warm period (P= 0.022), suggesting that selection for increased body size may have occurred. Increased metabolic efficiency of heterozygous enzymes or individuals is suggested as an explanation for the observed relationship between heterozygosity and intramuscular lipid level.
High ultrasonic and tremulation signals in neotropical katydids (Orthoptera: Tettigoniidae)
Authors: Morris G. K. , Mason A. C. , Wall P. , Belwood J. J.
Published: May 2009

Myopophyllum speciosum is a pseudophylline katydid (Tettigoniidae) from the neotropics that generates unusually high ultrasonic frequencies as the dominant carrier in its calling song. Male calls average only 148 ms duration and are given at long intervals: 8.7 s. Pairing is completed with vibrational signals, generated at closer range by body oscillation (tremulation). Two distinctive vibrational motor patterns, short and long, are produced by both sexes. Physical parameters of the sound and vibratory signals of this species are described. The relatively high‐Q carrier frequency (mean = 81 kHz) varies between males over a range of 20 kHz but does not predict a singer's body size. Short tremulations are much more intense than long as measured by acceleration. Descriptions of the songs of three other pseudophylline species with unusually high principal carriers (65–105 kHz) are also presented.

Eavesdropping by predatory bats offers the most plausible selective explanation for the features of M. speciosum's signal system. This hypothesis is supported by the species' sexually dimorphic defensive spination: males, the sound‐signalling sex, have metafemoral spines of greater size and distinctive orientation. Evidence for eavesdropping and for alternative hypotheses is assessed. Other neotropical tettigoniids in rainforest understorey also employ elaborate vibratory signals (species of Choeroparnops, Schedocentrus, Docidocercus, Copiphora) and some show a trend to reduce or even to eliminate their use of airborne sound. Some rainforest tettigoniids may have replaced acoustic with vibrational signalling as a response to bat eavesdropping.
Post‐prandial urine loss and its relation to ecology in brown long‐eared (Plecotus auritus) and Daubenton's (Myotis daubentoni) bats (Chiroptera: Vespertilionidae)
Authors: Webb P. I. , Speakman J. R. , Racey P. A.
Published: May 2009

Urine loss, over the first 12 hours after feeding, was positively and linearly dependent on food consumption in water‐denied, brown long‐eared bats (Plecotus auritus) and also in water‐denied and water‐provided, Daubenton's bats (Myotis daubentoni). The slope of the relationship (food‐dependent urine loss) (363 μ 1 g dry mass food−1, S.D.=±70, n=19) was not significantly different between the two species but predicted urine loss at zero food consumption (food‐independent urine loss) was significantly lower in P. auritus (0.048 μl.min−1, S.D. =±0.015, n= 12) than in M. duubentoni (0.217 μl min−1 S.D. =±0.040, n = 7). The same results were apparent if the data for M. daubentoni were restricted to water‐deprived animals only. Of total urine loss, 46% occurred in the first hour after feeding in M. daubentoni compared with only 20% in P. auritus. We suggest that the differences between the two species in the pattern of postprandial urine loss reflect their relative association with open water when foraging and roosting in the wild. In the course of the water‐denied experiment, M. duubentoni lost 15% of pre‐fed body mass and showed signs of severe dehydration, while P. auritus only lost 6% and did not. However, urine loss only accounted for 8–10% of body mass loss. A water budget model for wild P. auritus in the summer was developed and suggested that if bats did not drink, approximately 19% of water loss would be attributable to faecal water loss, 18–20% to urine loss, and 59–62% of intake would be available to support evaporation and reproductive losses.
Photoperiod control of birth timing in the harbour seal (Phoca vitulina)
Authors: Temte Jonathan L.
Published: May 2009

The harbour seal (Phoca vitulina) has delayed implantation, precise annual birth timing, and significant latitudinal variation in birth timing. The birth timing patterns of four distinct groups of seals, including colonies ofP. v. vitulinaand colonies and captive individuals of P.v. richardsi, were examined using population‐based photoperiod analysis to assess the role of photoperiod in setting annual birth timing. This analysis simultaneously determined the time, relative to birth, at which photoperiod response was likely to occur and the critical photoperiod.

Despite marked differences in birth timing patterns, a high level of agreement was found among groups for the timing of photoperiod response. The two subspecies, however, demonstrated significantly divergent critical photoperiods. Eastern Atlantic harbour seals were exposed to a common critical photoperiod of 11.7 h/day on the 268th pre‐partum day. Wild Pacific harbour seals were exposed to 14.3 h/day on the 283rd pre‐partum day. These times corresponded to the estimated occurrence of blastocyst implantation.

Using the above information, three small captive populations were subjected to artificially prolonged photoperiods during the period of embryonic diapause to test whether subsequent birth timing could be delayed. Technical difficulties invalidated results at two sites. At the third and largest colony, the mean pupping date of six individuals was significantly delayed by 10.7days.

The precision and latitudinal variation of annual birth timing in the harbour seal are due to a response to photoperiod which occurs immediately prior to blastocyst implantation. The critical photoperiod, however, is divergent among subspecies and, thus, has probably evolved allowing seasonal adaptation. Similar environmental signalling has been described for California sea lions and northern fur seals and represents the likely timing mechanism for most pinniped species.
Light and electron microscopical investigations on shell pores (caeca) of fissurellid limpets (Mollusca: Archaeogastropoda)
Authors: Reindl S. , Haszprunar G.
Published: May 2009

The organic content (caecum) of the shell pores of five species of fissurellid (key‐hole) limpets was investigated by means of light and electron microscopy. Fissurellid caeca are unbranched, polycellular extensions of the mantle epithelium, which penetrate the whole shell and contact the periostracum via organic fibres called ‘brush’. They are built up by two cell‐types, which enclose a central lumen, and are formed concurrently with the shell itself. Because of fundamental structural and developmental differences, the superficially similar shell pores of bivalves (caeca) and polyplacophorans (aesthetes) are considered as analogous rather than homologous organs. Similarities are found with brachiopod caeca, probably owing to similar functions.
Dental morphology and diet in anuran amphibians from south India
Authors: Das I. , Coe M.
Published: May 2009

The morphology of the jaw and palatine surfaces of eight species of metamorphosed anuran amphibians (Microhyla ornata, M. rubra, Uperodon systoma, Tomopterna rolandae, Polypedates maculatus, Rana cyanophlycris, R. crassaandR. hexadactyla) from a locality in south India, were examined by scanning electron microscopy. A relationship was observed between dentition (or its absence) and diet. In large prey feeders, there is a strong tendency towards the development of large secondary (or even tertiary) cusps, while myrmecophagous and termitophagous species lack teeth.

In the largely folivorous adults ofRana hexadactyla, secondary cusps are reduced to faint ridges and the tooth is cylindro‐conical (as opposed to the recurved teeth with apices oriented lingually or distally in the insectivorous species). Although the phylogenetic relationships within members of the community are largely unknown, the oral armature is reflective of diet, and may represent adaptive suites.
Erect tube growth in Rhabdopleura compacta (Hemichordata: Pterobranchia) from off Start Point, Devon
Authors: Rigby Susan
Published: May 2009

Patterns of tube construction in the upright tubes of Rhabdopleura compacta are described. Tube building is seen to be a highly regular process, with growth extending over more than one season. Participation in the building of any one tube can involve multiple generations of zooids. Spatial awareness in a zooid adding new material to a pre‐existing tube can be demonstrated. This shows that the construction of the tube is strictly determined, either by environmental or genetic mechanisms, rather than being a function of developing zooid morphology, as previously suggested, or random processes.
Food choice and food competition among the three major primate species of French Guiana
Authors: Guillotin M. , Dubost G. , Sabatier D.
Published: May 2009

The three most important primates of French Guiana are frugivorous species, but to different degrees. Ateles paniscus is almost exclusively frugivorous, Alouatta seniculus frugivorous‐folivorous, and Cehus apellu partially insectivorous; thus, the overall specific diet spectra arc well separated. During the season when fruit production is minimal, fruit intake by all species is also minimal which results in the greatest diversities in diet and the lowest diet overlaps. Real competition for the common main food category, i.e. fruits, only occurs during the most favourable period. Nevertheless, some fruit characteristics (e.g. size…) separate the monkey species from each other in fruit choice and make the interspecific competition of little importance.
Behavioural time budget of breeding king penguins (Aptenodytes patagonica)
Authors: Challet E. , Bost C.‐A. , Handrich Y. , Gendner J.‐P. , Maho Y. Le
Published: May 2009

As do so many other seabirds, penguins fast when ashore for breeding. For penguins in dense colonies, territory defence seems to imply conflicting energetic requirements because of its assumed high energy cost, when the birds need to limit energy expenditure to cope with their fast. In this context, behavioural time budget over 24 h was investigated during breeding in the king penguin, Aptenodytes putugonicu, by using a remote‐controlled videocamera. The comparison of day‐night activity was performed in relation to breeding status (incubation vs. brooding) and duration of fasting (beginning vs. end of incubation shift). Five categories of behaviours were quantified: territoly defence, comfort, resting, sleeping and chick‐feeding. Breeding king penguins remain active by day as well as by night. Between incubation and brooding we found a three‐fold increase in the energy consuming temtory defence, together with a drastic decrease in that posture which corresponds to deep sleep, is. when most energy is saved. These increases in aggressiveness and vigilance may be related to protection of the newly hatched chick. Between the onset and the end of an incubation shift, the time spent in sleep increases three‐fold, whereas territory defence remains unchanged. These data for penguins under natural conditions accord with previous studies on captive birds which have shown that an increasing proportion of sleep during the course of fasting may contribute to energy saving. On the other hand, both resting (which is the main component of penguins’time budget; about 65%) and comfort (about 16% of time) show no change either between incubation and brooding or during the course of fasting.
Prey selection and foraging constraints in common poorwills (Phalaenoptilus nuttallii: Aves: Caprimulgidae)
Authors: Bayne E. M. , Brigham R. M.
Published: May 2009

Predators that hunt by sight should be constrained by light levels. This problem should be especially acute in aerial predators such as common poorwills (Phalaenoptilus nuttallii: Caprimulgidae), which capture small insects at night. The purpose of our study was to test the hypothesis that poorwills are constrained to catching larger insect taxa due to limitations of visual orientation under low light. We assessed diet by analysing poorwill faecal samples collected at nest and roost sites in the Cypress Hills of Saskatchewan where prey density is relatively low. Coleopterans (44% and 39% in 1991 and 1992, respectively) and lepidopterans (46% and 55%) dominated the diet, yet these two insect orders were rare in light‐suction trap (22% lepidopterans and 1% coleopterans) and sticky trap samples (11% lepidopterans and 2% coleopterans). Based on measurements of femur length, all consumed coleopterans were > 5 mm long, even though 57% of those available were < 5 mm. Our results suggest that poorwills are constrained to taking prey above a certain size, but above this threshold, particular prey types and larger sizes may be selected. Selection for coleopterans may reflect the need to acquire polyunsaturated fat to facilitate the use of torpor.
Do lambs affect feeding habitat use by lactating female mouflons in spring in areas free of predators?
Authors: Bon R. , Joachim J. , Maublanc M. L.
Published: May 2009

The purpose of this study was to see if mouflon (Ovis gmelini) females with lambs have feeding habitats similar to other sex‐age classes in spring, in an area without large natural predators. Parous ewes restricted themselves to rocky and poor nutritive habitats but lambed within their winter home range. Once in matriarchal groups, females with lambs ≥ three days old fed more on rocky areas and stayed closer to safe terrain than did other mouflons which more frequently used slope tops, patches containing herbs, and pastures around a little village. Segregation between the two categories of mouflons was reduced when lambs were several weeks old during the peak growing season. Seclusion of parous females may be explained by potential predation by foxes on neonates, an asocial tendency, the need to form mother‐young bonds and the necessity for the young to develop locomotor skills. Rocky areas may also provide favourable microclimatic conditions. Two non‐exclusive hypotheses may account for the tendency of lactating females to remain near ‘escape’ terrain. First, the anti‐predator strategy could be driven in the absence of predators because of phylogenetic inertia. Secondly, the anti‐predator strategy may be learned during the autumn hunting season and exhibited during the lambing season even without predation.
Post‐natal growth, mother‐infant interactions and development of vocalizations in the vespertilionid bat Plecotus auritus
Authors: de Fanis E. , Jones G.
Published: May 2009

Female brown long‐eared bats Plecotus auritus nurse their own young selectively. Choice experiments suggested that females recognized infants by using both olfactory and acoustic cues. Infant isolation calls (i‐calls) showed individual variation, and vocal signatures allowed the females to recognize and suckle their own pup. As the pups grew, the i‐calls increased in frequency and decreased in duration, and the i‐calls appeared to change into orientation cries. Mothers were able to recognize recent calls of their own babies in preference to older calls. Echolocation sounds were distinguishable statistically between lactating females, and the behaviour of the babies during choice experiments suggested that in this species a mutual acoustic recognition occurs. The growth and development of wing shape in P. auritus are described.
Influence of oviposition date and temperature upon embryonic development in Somatochlora alpestris and S. arctica (Odonata: Corduliidae)
Authors: Sternberg Klaus
Published: May 2009

In two bog‐dwelling dragonflies, Somatochlora alpestris and S. arctica, the influence of oviposition date and temperature upon duration of embryonic development was studied. Egg diapause was facultative. With advancing season, the proportion of diapause eggs increases from 0 to 37% in S. alpestris and from 0 to 18% in S. arctica. Eggs needed at least 17 to 38 days for development. Hatching curves were temperature‐independent in nearly all experiments but developmental rate increased at higher ambient temperature. In S. arctica, responses of developmental rate to temperature differed in eggs laid on different dates. In S. alpestris, duration of egg development decreased as season progressed. The duration of egg development of non‐diapause eggs and proportion of diapause eggs in S. alpestris and possibly in S. arctica may also both be a function of female age at the time of oviposition. The ecological significance of the different development patterns is discussed.
Relative warp analysis of skull shape across the hybrid zone of the house mouse (Mus musculus) in Denmark.
Authors: Auffray J.‐C. , Alibert P. , Latieule C. , Dod B.
Published: May 2009

The changes in skull shape that occur in the hybrid zone between the two European subspecies of the house mouse (Mus musculus musculusandM. m. domesticus) were studied by relative warp analyses. Landmarks observed on the ventral view of the skulls of 269 mice sampled in 18 localities in Denmark were analysed. Each population was also characterized by a hybrid index estimated from allozymic data. Although no clear pattern of within‐population variability of shape could be established across the hybrid zone, the shape changes among the 18 populations were found to be correlated with the allozymic introgression but not with geographical location. Finally, the cline obtained for skull shape seems to be steeper than that corresponding to the average allozyme hybrid index which suggests that skull development could be slightly perturbed in hybrids.
Sexually dimorphic head sizes and reproductive success in the sleepy lizardTiliqua rugosa
Authors: Bull C. Michael , Pamula Yvonne
Published: May 2009

In 1993, 458 males and 346 females of the largve Australian skink,Tiliqua rugosa, were captured in a study area near Mt. Mary, South Australia. Females were significantly longer than males, although there was broad overlap in snout‐vent length measures. Males had significantly longer and broader heads than females of equivalent snout‐vent length. In the spring some, but not all, lizards formed monogamous pairs. Pairing was used as an indirect indicator of reproductive success. When all adult males were considered there was no significant difference in head size between those found paired or unpaired. However, among small adults, paired males had signficantly broader heads than unpaired males. This supports the hypothesis that head size is under sexual selection. Individuals with wider heads could be more successful in male‐male combat where jaws are the major offensive weapon. Younger, smaller males with a wise head could gain mates at an earlier age. Females showed a different pattern. In all females, and most strongly amongst larger size classes, paired females had significantly larger heads than unpaired females. An explanation is that larger heads somehow reduce the chance that a female will skip a year of reproduction, although the mechanism is not clear.
Reproductive biology of female striped dolphin (Stenella coeruleoalba) from the western Mediterranean
Authors: Calzada N. , Aguilar A. , Sørensen T. B. , Lockyer C.
Published: May 2009

Data on age and length at sexual maturity, calving interval, lactation period, and ovulation and pregnancy rates were analysed from 84 female striped dolphin collected during the Mediterranean morbillivirus epizootic. Age was determined by counting growth layer groups in tooth dentine, and reproductive status was determined by the macroscopic examination of the ovaries and the uterus. Age at sexual maturity (ASM) was estimated using two different methods; giving average estimates of 12 and 12.3 years. The average length at sexual maturity was 187 cm and the calving interval was four years. The annual pregnancy rate (APR) was calculated using two different criteria. In the first, only females that were pregnant at the time of death, as evidenced by the presence of a foetus, were incorporated in the calculations. This method gave an estimate of 8.9% as the apparent pregnancy rate of the dolphins killed by the epizootic. The second method incorporated in the calculations females that were pregnant at the time of death and females that had young corpus albicans in the ovaries and a distended uterus. This method is considered to reflect the true pregnancy rate of the population and gave an estimate of 25%. Estimates of ovulation rate (0.401) and lactation period (16 months) were considered to be potentially affected by the disease and, therefore, biased. These estimates reflect a peculiar situation of the diseased dolphins but are useful for comparative purposes. Estimates of ASM and APR, parameters which are not likely to be affected by the disease, differed markedly from those of other Stenella populations and could indicate a density‐dependent response, possibly reflecting food limitations.