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Hares
Kinds of Hares Selected AbstractsHyaluronan and its receptors in mucoepidermoid carcinomaHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 2 2006Richard O. Wein MD Abstract Background. Hyaluronan (HA) is a prominent extracellular matrix component undergoing continuous production and degradation. Increased HA levels have been described in a variety of tumors. The objective of this study was to examine the staining patterns of HA and two of its associated receptors (CD44 and HARE) in relation to the metastatic potential of mucoepidermoid carcinoma (MC). Immunohistochemical staining of preserved surgical specimens was used. Methods. Tissues from 12 patients with a histologic diagnosis of salivary MC (10 parotid, one submandibular gland, one minor salivary gland) were studied. Half (six of 12) of the patients had regional metastases. Tumor, normal salivary tissue, and regional lymph nodes were stained for HA, CD44, and HARE expression. Specimens were graded for staining intensity and a percent of the specimen stained. Results. Normal salivary tissue did not demonstrate epithelial cell surface HA expression, whereas HA was expressed on tumor cells and in regional lymph nodes containing metastases. These differences were both significant using Student's t test (p < .00002, and p < .0022, respectively). Tumors with positive nodes tended to have greater cell surface HA. Decreased expression or downregulation of HARE was also noted in involved lymph nodes. No differences in CD44 expression were seen between primary specimens and lymph nodes. The observed staining patterns for CD44 and HARE were not reflective of the metastatic potential of the primary MC. Conclusions. Increased HA expression was seen on mucoepidermoid carcinoma cells compared with adjacent normal salivary gland epithelium. This observation may assist in explaining the development of regional metastasis in these tumors. We did not identify specific HA, CD44, or HARE staining patterns in primary lesions that were predictive of regional metastases. © 2005 Wiley Periodicals, Inc. Head Neck27: XXX,XXX, 2005 [source] A Two-country Comparison of Public Sector Performance Reporting: The Tortoise and Hare?FINANCIAL ACCOUNTABILITY & MANAGEMENT, Issue 3 2001Mark Christensen Recent Australian and Japanese second tier public sector performance measurement changes are compared and contrasted. The case analyses are presented within a theoretical structure derived from Hood's depiction of NPM which predicts an increased emphasis on explicit performance reporting. Significant differences and similarities are identified in terms of performance reporting effort and output; motivation for changed performance reporting; role of central agencies; and degree of resultant accountability discharge. NPM is a useful analytical framework and is enhanced by Luder's Contingency Model, epistemic community influence and governance. The explanatory factors identified reinforce views that NPM is a term best used solely in the context of the governmental traditions of each relevant public sector. [source] Mothering in Public: A Meta-Synthesis of Homeless Women With Children Living in SheltersJOURNAL FOR SPECIALISTS IN PEDIATRIC NURSING, Issue 4 2003MPHArticle first published online: 24 AUG 200, Mikki Meadows-Oliver MSN ISSUES AND PURPOSE The purpose of this paper is to synthesize the current qualitative literature on homeless women with children living in shelters. METHODS Eighteen qualitative studies on homeless women with children living in shelters were included in the synthesis. The meta-synthesis was conducted using the meta-ethnographic approach of Noblit and Hare (1988). RESULTS Six reciprocal translations (themes) of homeless mothers caring for their children in shelters emerged: On becoming homeless, protective mothering, loss, stressed and depressed, survival strategies, and strategies for resolution. PRACTICE IMPLICATIONS The results may be used by healthcare workers as a framework for developing intervention strategies directed toward helping mothers find new solutions to dealing with shelter living and innovative ways to resolve their homelessness. [source] The Golden Rule and the Potentiality Principle: Future Persons and Contingent InterestsJOURNAL OF APPLIED PHILOSOPHY, Issue 1 2004Kai M. A. Chan abstract,Duties to future persons are central to numerous key ethical issues including contraception, abortion, genetic selection, treatment of the environment, and population control. Nevertheless, we still seem to be lacking Parfit's ,Theory X', a general theory of beneficence whose appropriateness extends to future generations. Starting from the Golden Rule (TGR), R. M. Hare purportedly derived counterintuitive duties to potential people and ,the potentiality principle'. However, I argue that Hare's derivation involves a hidden and unjustifiable extension from TGR, and show how the most plausible form of TGR is compatible with multiple contradictory principles for the treatment of future persons. I appeal to our own preferences to argue that one extension of TGR follows the spirit of TGR, while the other is deeply implausible. Using the plausible extension, I derive a Contingent Interests Principle (CIP) that offers much promise as Parfit's elusive Theory X. In contrast to Hare's interpretation of TGR, this application provides solid justification for rejecting the potentiality principle. [source] Obituary: Richard Mervyn HareJOURNAL OF APPLIED PHILOSOPHY, Issue 3 2002James Griffin No abstract is available for this article. [source] Effects of moisture, nitrogen, grass competition and simulated browsing on the survival and growth of Acacia karroo seedlingsAFRICAN JOURNAL OF ECOLOGY, Issue 4 2009Keletso Mopipi Abstract The effects of irrigation, nitrogen fertilization, grass competition and clipping were investigated for one growing season at the research farm of the University of Fort Hare in the Eastern Cape Province of South Africa. The aim of the experiment was to assess the short-term performance of Acacia karroo seedlings under different environmental conditions and the implications of such factors on the long-term recruitment of plant species in savanna rangelands. There were no significant treatment effects on the survival of A. karroo seedlings. Using stem length and basal diameter as growth parameters, it was observed that irrigation enhanced both variables, while nitrogen fertilization did not have any significant effects. Clipping, grass competition and their interaction greatly suppressed the growth of the seedlings. Clipping increased the mean stem length when they were irrigated and fertilized. Control and fertilized plants had the highest stem length in the absence of grass competition, while grass competition combined with clipping resulted in the lowest stem length in both irrigated and nonirrigated plants. It was concluded that in the presence of grass competition, controlled browsing could be a viable solution to the problem of bush encroachment in savanna rangelands. Résumé Les effets de l'irrigation, d'une fertilisation à l'azote, de la compétition avec l'herbe et de la taille ont étéétudiés pendant une saison de croissance dans la ferme expérimentale de l'Université de Fort Hare, dans la Province du Cap oriental, en Afrique du Sud. Le but de l'expérience était d'évaluer les performances à court terme de jeunes plants d'Acacia karroo dans différentes conditions expérimentales, et les implications de ces facteurs sur le recrutement à long terme d'espèces végétales dans des pâturages de savane. Il n'y a pas eu d'effet significatif des traitements sur la survie des plants d'A. karroo. En utilisant la longueur des troncs et le diamètre de la base comme indicateurs de croissance, on a observé que l'irrigation augmentait les deux variables, alors que la fertilisation à l'azote n'avait aucun effet significatif. La taille, la compétition avec l'herbe et leur interaction supprimait fortement la croissance des jeunes plants. La taille augmentait la longueur moyenne des troncs lorsqu'ils étaient irrigués et fertilisés. Les plants témoins et les plants fertilisés avaient les troncs les plus longs en absence de toute compétition avec des herbes, alors que cette dernière, combinée avec la taille, aboutissait à la longueur la plus petite des troncs, chez les plants irrigués ou non. On en a conclu qu'en cas de compétition avec des herbes, un pâturage contrôlé pourrait être une solution viable au problème de l'envahissement des broussailles dans les pâturages de savane. [source] Examining psychopathic tendencies in adolescence from the perspective of personality theoryAGGRESSIVE BEHAVIOR, Issue 5 2009Naomi Sadeh Abstract This study sought to clarify the personality correlates of psychopathic tendencies in adolescents using the Antisocial Process Screening Device [APSD; Frick and Hare, 2001] and a youth adapted version of the Multidimensional Personality Questionnaire [Patrick et al., 2009, unpublished]. A combination of self- and parent-reports on the APSD (n=229) revealed that the three-facet model of psychopathic tendencies in youth was characterized by a similar constellation of personality traits as the psychopathic construct in adulthood [e.g., Hall, Benning and Patrick, 2004]. Specifically, low anxiety and trait aggression characterized the APSD Callous/Unemotional dimension, social dominance and trait aggression characterized the APSD Narcissism dimension, and disinhibition and low harm avoidance characterized the APSD Impulsivity dimension. The results add credence to the hypothesis that personality relationships to psychopathic tendencies emerge from an early age [Lynam, 2002] and dimensions of psychopathy in youth are associated with distinct personality profiles. Aggr. Behav. 35:399,407, 2009. © 2009 Wiley-Liss, Inc. [source] A METAETHICAL OPTION FOR THEISTSJOURNAL OF RELIGIOUS ETHICS, Issue 1 2006Kyle Swan ABSTRACT John Hare has proposed "prescriptive realism" in an attempt to stake out a middle-ground position in the twentieth century Anglo-American debates concerning metaethics between substantive moral realists and antirealist-expressivists. The account is supposed to preserve both the normativity and objectivity of moral judgments. Hare defends a version of divine command theory. The proposal succeeds in establishing the middle-ground position Hare intended. However, I argue that prescriptive realism can be strengthened in an interesting way. [source] The use of willingness-to-pay approaches in mammal conservationMAMMAL REVIEW, Issue 2 2001Piran C. L. White ABSTRACT With limited monetary resources available for nature conservation, policy-makers need to be able to prioritize conservation objectives. This has traditionally been done using qualitative ecological criteria. However, since declines in species and habitats are largely the result of socio-economic and political forces, human preferences and values should also be taken into account. An environmental economics technique, contingent valuation, provides one way of doing this by quantifying public willingness-to-pay towards specific conservation objectives. In this paper, the use of this approach for quantifying public preferences towards the UK Biodiversity Action Plans for four different British mammal species is considered. The species included are the Red Squirrel Sciurus vulgaris, the Brown Hare Lepus europaeus, the Otter Lutra lutra and the Water Vole Arvicola terrestris. Willingness-to-pay for conservation was increased by the inclusion of the Otter among the species, membership of an environmental organization and awareness of the general and species-specific threats facing British mammals. It was reduced by the presence of the Brown Hare among the species being considered. These findings for British mammals are compared with other willingness-to-pay studies for mammal conservation worldwide. Willingness-to-pay tends to be greater for marine mammals than terrestrial ones, and recreational users of species (tourists or hunters) are generally more willing than residents to pay towards species conservation. The choice of technique for eliciting willingness-to-pay from respondents is also shown to be highly significant. Willingness-to-pay values for British mammals derived from contingent valuation are sensitive to the species included rather than merely symbolic. This indicates that, with care, such measures can be used as a reliable means of quantifying public preferences for conservation, and therefore contributing to the decision-making process. However, irrespective of the internal consistency of contingent valuation, the validity of the approach, especially for use in nature conservation, is disputed. Willingness-to-pay is likely to reflect many interrelated factors such as ethical and moral values, knowledge and tradition, and monetary values may not be an adequate representation of these broader considerations. Willingness-to-pay approaches should therefore be used in addition to, rather than in place of, expert judgements and more deliberative approaches towards policy decision-making for conservation. [source] Advancing E-Government at the Grassroots: Tortoise or Hare?PUBLIC ADMINISTRATION REVIEW, Issue 1 2005Donald F. Morris American grassroots governments have rushed to join the e-government revolution. Although there is a growing body of e-government literature, little of it is empirical. Using data from two nationwide surveys, we conduct a longitudinal examination of local government adoption of e-government, Web site sophistication, the perceived impacts of e-government, and barriers to the adoption and sophistication of e-government. We also discuss correlates of e-government adoption and sophistication with selected institutional factors. We find that e-government adoption at the grassroots is progressing rapidly (if measured solely by deployment of Web sites). However, the movement toward integrated and transactional e-government is progressing much more slowly. Continuing research, particularly longitudinal study, is needed to monitor the evolution of e-government among U.S. local governments, especially to keep pace with the practice and to ascertain the actual impacts of e-government. [source] Position and Histological Structure of the Testes in the Brown Hare (Lepus europaeus) during Seasonal Regression and RecrudescenceANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2000B. Simeunovi The position and histological structure of the testes of 33 brown hares (Lepus europaeus) were studied from July to December. From July to September, the testes were located in the scrotum; in October and November, in some animals, the testes were positioned more or less in the inguinal canal towards the abdominal cavity, and in December none of the investigated animals had testes located in the scrotum. Testes were weighed and a quantitative analysis of tissue components was performed: the diameter of the seminiferous tubules, the depth of the seminiferous epithelium, the thickness of the tunica albuginea, the thickness of the peritubular tissue and the relative proportion of seminiferous tubules were determined. The tunica albuginea and peritubular tissue were thickest in September, October and at the beginning of November. In the same months the testis weight was low, and the diameter of the seminiferous tubules, the depth of the seminiferous epithelium and the relative proportion of seminiferous tubules in the testis tissue were significantly lower than in other months. We did not find any correlation between testicular regression or testis weight reduction and the change in the position of the testes. During recrudescence of spermatogenesis in November and December the testes were located in the inguinal canal. [source] Sir William Mackenzie: sympathetic ophthalmia and glaucoma before ophthalmoscopyANZ JOURNAL OF SURGERY, Issue 12 2009Geoffrey Serpell Abstract One of the practitioners of probably the oldest surgical specialty, ophthalmic, was the eminent Scottish ophthalmologist, Sir William Mackenzie. Educated in Edinburgh, he moved to Glasgow, and described and named sympathetic ophthalmia before the time of the ophthalmoscope, well defining his powers of observation and deduction. Founding the Glasgow Eye Infirmary, his ,Practical Treatise on Diseases of the Eye' appeared in English in four editions (1850,1884) and in French and German. In this also appears the first full and clear account of glaucoma. Both he and the illustrator of his book, Wharton Jones, moved to Glasgow because of rather indefinite connections with Robert Knox, the anatomist, who was allegedly helped by the bodysnatchers, Burke and Hare. Mackenzie and his book were highly regarded before the revolutionary ophthalmoscope. He was knighted and appointed Surgeon Oculist to the Queen in Scotland. [source] Psychopathy in adolescent female offenders: an item response theory analysis of the psychopathy checklist: youth versionBEHAVIORAL SCIENCES & THE LAW, Issue 1 2006Crystal L. Schrum M.A. The present study examined the applicability of the PCL:YV items to a sample of detained adolescent girls. Item response theory (IRT) was used to analyze test and item functioning of the PCL:YV. Examination of IRT trace lines indicated that the items most discriminating of the underlying construct of psychopathy included "callousness and a lack of empathy", "conning and manipulation", and "a grandiose sense of self-worth". Results from the analyses also demonstrated that the items least discriminating in this sample, or least useful for identifying psychopathy, included "poor anger control", "shallow affect", or engaging in a "serious violation of conditional release". Consistent with previous research (Cooke & Michie, 1997; Hare, 2003), interpersonal and affective components of psychopathy provided more information than behavioral features. Moreover, although previous research has also found affective features to provide the most information in past studies, it was interpersonal features of psychopathy in this case, followed by affective features, that provided greater levels of information. Implications of these results are discussed. Copyright © 2006 John Wiley & Sons, Ltd. [source] Psychopathic traits in adolescent offenders: an evaluation of criminal history, clinical, and psychosocial correlates,BEHAVIORAL SCIENCES & THE LAW, Issue 1 2004Mary Ann Campbell Ph.D. Although a large body of research has established the relevance of psychopathy to adult offenders, its relevance to adolescent offenders is far less clear. The current study evaluated the clinical, psychosocial and criminal correlates of psychopathic traits in a sample of 226 male and female incarcerated adolescent offenders. According to an 18-item version of the Psychopathy Checklist,Youth Version (PCL-YV; Forth, Kosson, & Hare, 2003), only 9.4% exhibited a high level of psychopathic traits (PCL-YV,25). Consistent with past research, higher PCL-YV scores were positively associated with self-reported delinquency and aggressive behavior and were unrelated to emotional difficulties. Although higher PCL-YV scores were associated with the experience of physical abuse, the only psychosocial factor to predict PCL-YV scores was a history of non-parental living arrangements (e.g. foster care). In terms of criminality, a violent/versatile criminal history was positively associated with psychopathic traits. However, PCL-YV scores were unrelated to participants' official criminal records for total, non-violent, violent, and technical violation convictions. In conclusion, the data partially support the construct validity of psychopathy with adolescent offenders, but some inconsistencies with prior adult and adolescent psychopathy research were evident. These issues are discussed. Copyright © 2004 John Wiley & Sons, Ltd. [source] The sensitive hare: sublethal effects of predator stress on reproduction in snowshoe haresJOURNAL OF ANIMAL ECOLOGY, Issue 6 2009Michael J. Sheriff Summary 1.,Prey responses to high predation risk can be morphological or behavioural and ultimately come at the cost of survival, growth, body condition, or reproduction. These sub-lethal predator effects have been shown to be mediated by physiological stress. We tested the hypothesis that elevated glucocorticoid concentrations directly cause a decline in reproduction in individual free-ranging female snowshoe hares, Lepus americanus. We measured the cortisol concentration from each dam (using a faecal analysis enzyme immunoassay) and her reproductive output (litter size, offspring birth mass, offspring right hind foot (RHF) length) 30 h after birth. 2.,In a natural monitoring study, we monitored hares during the first and second litter from the population peak (2006) to the second year of the decline (2008). We found that faecal cortisol metabolite (FCM) concentration in dams decreased 52% from the first to the second litter. From the first to the second litter, litter size increased 122%, offspring body mass increased 130%, and offspring RHF length increased 112%. Dam FCM concentrations were inversely related to litter size (r2 = 0·19), to offspring birth mass (r2 = 0·32), and to offspring RHF length (r2 = 0·64). 3.,In an experimental manipulation, we assigned wild-caught, pregnant hares to a control and a stressed group and held them in pens. Hares in the stressed group were exposed to a dog 1,2 min every other day before parturition to simulate high predation risk. At parturition, unsuccessful-stressed dams (those that failed to give birth to live young) and stressed dams had 837% and 214%, respectively, higher FCM concentrations than control dams. Of those females that gave birth, litter size was similar between control and stressed dams. However, offspring from stressed dams were 37% lighter and 16% smaller than offspring from control dams. Increasing FCM concentration in dams caused the decline of offspring body mass (r2 = 0·57) and RHF (r2 = 0·52). 4.,This is the first study in a free-ranging population of mammals to show that elevated, predator-induced, glucocorticoid concentrations in individual dams caused a decline in their reproductive output measured both by number and quality of offspring. Thus, we provide evidence that any stressor, not just predation, which increases glucocorticoid concentrations will result in a decrease in reproductive output. [source] Overwinter mass loss of snowshoe hares in the Yukon: starvation, stress, adaptation or artefact?JOURNAL OF ANIMAL ECOLOGY, Issue 1 2006KAREN E. HODGES Summary 1Overwinter mass loss can reduce energetic requirements in mammals (Dehnel's phenomenon). Alternatively, mass loss can result from food limitation or high predation risk. 2We use data from fertilizer, food-supplementation and predator-exclusion experiments in the Yukon during a population cycle from 1986 to 1996 to test the causes of overwinter mass loss by snowshoe hares (Lepus americanus). In all years, some hares on control sites gained mass overwinter. During the increase phase the majority gained mass, but in all other phases the majority lost mass. 3Snowshoe hares weighing < 1000 g in autumn always gained mass overwinter, as did the majority that weighed 1000,1400 g. Hares weighing > 1800 g in autumn usually lost mass. 4Snowshoe hares on the predator-exclosure + food site gained mass overwinter in all years. Hares on the food-supplementation sites lost mass during the decline but gained mass in all other phases. Fertilization had little effect on mass dynamics. 5Snowshoe hares were more likely to lose mass during winters with low survival rates. Snowshoe hares on the predator-exclosure treatments were more likely to gain mass than were hares on control sites. 6Overwinter mass loss was correlated with maximum snow depth. At equivalent snow depths, hares on food-supplemented areas lost 98 g (± 14·6 SE) less on average than hares on the controls and predator-exclosure treatment. 7Bone-marrow fat was related to body mass and cause of death. Small hares had the lowest marrow fat. Hares killed by humans had higher marrow fat than those killed by predators; hares that simply died had the lowest marrow fat. Hares on food-supplemented sites had the highest kidney and marrow fat. 8Overwinter-mass loss for snowshoe hares is explained interactively by winter conditions, food supply, predation risk and autumn mass. Some snowshoe hares lost mass overwinter in all years and on all treatments, suggesting that reducing body mass may facilitate survival, especially in cases where foraging costs are high energetically or increase predation risk. [source] The rise and fall of the mountain hare (Lepus timidus) during Pleistocene glaciations: expansion and retreat with hybridization in the Iberian PeninsulaMOLECULAR ECOLOGY, Issue 3 2007J. MELO-FERREIRA Abstract The climatic fluctuations during glaciations have affected differently arctic and temperate species. In the northern hemisphere, cooling periods induced the expansion of many arctic species to the south, while temperate species were forced to retract in southern refugia. Consequently, in some areas the alternation of these species set the conditions for competition and eventually hybridization. Hares in the Iberian Peninsula appear to illustrate this phenomenon. Populations of Iberian hare (Lepus granatensis), brown hare (Lepus europaeus) and broom hare (Lepus castroviejoi) in Northern Iberia harbour mitochondrial haplotypes from the mountain hare (Lepus timidus), a mainly boreal and arctic species presently absent from the peninsula. To understand the history of this past introgression we analysed sequence variation and geographical distribution of mitochondrial control region and cytochrome b haplotypes of L. timidus origin found in 378 specimens of these four species. Among 124 L. timidus from the Northern Palaearctic and the Alps we found substantial nucleotide diversity (2.3%) but little differentiation between populations. Based on the mismatch distribution of the L. timidus sequences, this could result from an expansion at a time of temperature decrease favourable to this arctic species. The nucleotide diversity of L. timidus mtDNA found in Iberian L. granatensis, L. europaeus and L. castroviejoi (183, 70 and 1 specimens, respectively) was of the same order as that in L. timidus over its range (1.9%), suggesting repeated introgression of multiple lineages. The structure of the coalescent of L. granatensis sequences indicates that hybridization with L. timidus was followed by expansion of the introgressed haplotypes, as expected during a replacement with competition, and occurred when temperatures started to rise, favouring the temperate species. Whether a similar scenario explains the introgression into Iberian L. europaeus remains unclear but it is possible that it hybridized with already introgressed L. granatensis. [source] Habitat-dependent foraging in a classic predator,prey system: a fable from snowshoe haresOIKOS, Issue 2 2005Douglas W. Morris Current research contrasting prey habitat use has documented, with virtual unanimity, habitat differences in predation risk. Relatively few studies have considered, either in theory or in practice, simultaneous patterns in prey density. Linear predator,prey models predict that prey habitat preferences should switch toward the safer habitat with increasing prey and predator densities. The density-dependent preference can be revealed by regression of prey density in safe habitat versus that in the riskier one (the isodar). But at this scale, the predation risk can be revealed only with simultaneous estimates of the number of predators, or with their experimental removal. Theories of optimal foraging demonstrate that we can measure predation risk by giving-up densities of resource in foraging patches. The foraging theory cannot yet predict the expected pattern as predator and prey populations covary. Both problems are solved by measuring isodars and giving-up densities in the same predator,prey system. I applied the two approaches to the classic predator,prey dynamics of snowshoe hares in northwestern Ontario, Canada. Hares occupied regenerating cutovers and adjacent mature-forest habitat equally, and in a manner consistent with density-dependent habitat selection. Independent measures of predation risk based on experimental, as well as natural, giving-up densities agreed generally with the equal preference between habitats revealed by the isodar. There was no apparent difference in predation risk between habitats despite obvious differences in physical structure. Complementary studies contrasting a pair of habitats with more extreme differences confirmed that hares do alter their giving-up densities when one habitat is clearly superior to another. The results are thereby consistent with theories of adaptive behaviour. But the results also demonstrate, when evaluating differences in habitat, that it is crucial to let the organisms we study define their own habitat preference. [source] Ultrastructural and histochemical study of the salivary glands of Aplysia depilans (Mollusca, Opisthobranchia)ACTA ZOOLOGICA, Issue 3 2001Alexandre Lobo-da-Cunha Abstract The digestive system of the sea hare, Aplysia depilans, includes a pair of ribbon-shaped salivary glands. A central duct and a large blood vessel run close to each other along the length of these glands and both are surrounded by a layer of muscle cells. Three cell types form the glandular epithelium: granular cells, vacuolated cells and mucocytes. The granular cells possess cilia and spherical secretion granules, located primarily in the apical region. The granules of immature cells have a low electron density and are mainly formed by neutral polysaccharides with small amounts of proteins. The granules of mature cells are larger, have a high electron density and are mainly formed by proteins with lower amounts of neutral polysaccharides. Transition stages between immature and mature granular cells are observed. The vacuolated cells are large and frequently pyramidal in shape, but after the application of histochemical techniques almost all vacuoles remain uncoloured. The numerous vacuoles contain flocculent material in a clear background and the mitochondria possess large crystalline structures in the matrix. A pyramidal shape is also typical of the mucocytes, which are filled with vesicles containing granular masses surrounded by a network of secretion material. These large cells are strongly stained by Alcian blue, revealing the presence of acidic mucopolysaccharides. This is the first ultrastructural study of the salivary glands in opisthobranch gastropods. [source] Carnivores and their prey in the Wezmeh Cave (Kermanshah, Iran): a Late Pleistocene refuge in the ZagrosINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 6 2009M. Mashkour Abstract Wezmeh Cave is located on the northeastern edge of the Islamabad plain, a high intermontane valley in the western-central Zagros. In 1999 a disturbed but large faunal assemblage was recovered from this site. The abundant and extremely diverse faunal spectra present at Wezmeh Cave has highlighted the importance of this assemblage. Carnivore remains constitute the bulk of the assemblage; red fox (Vulpes vulpes) has the highest number of identified specimens followed by spotted hyena (Crocuta crocuta), brown bear (Ursus arctos), wolf (Canis lupus), felids (lion, leopard, lynx/caracal and wildcat), mustelids (badger, polecat, marten) and viverrids (mongoose). Artiodactyls (bovid, cervid, suid), equids, rhinoceros (Dicerorhinus sp.) and small animals (Cape hare, porcupine, tortoise, snake, birds) are also present. According to U-series dating, the site was occupied from around 70 ka BP through to sub-recent periods by carnivores. Amongst this rich assemblage, a human fossil tooth was also found and dated by non-invasive spectrometry gamma dating to 20,25 ka BP. A preliminary zooarchaeological and taphonomic study shows that Wezmeh Cave was used by multiple carnivore species, a unique phenomenon in the Zagros Mountains in particular and southwest Asia in general. Copyright © 2008 John Wiley & Sons, Ltd. [source] Functional anatomy and muscle moment arms of the pelvic limb of an elite sprinting athlete: the racing greyhound (Canis familiaris)JOURNAL OF ANATOMY, Issue 4 2008S. B. Williams Abstract We provide quantitative anatomical data on the muscle,tendon architecture and geometry of the pelvic limb of an elite sprint athlete, the racing greyhound. Specifically, muscle masses, muscle lengths, fascicle lengths, pennation angles and muscle moment arms were measured. Maximum isometric force and power of muscles, the maximum muscle torque at joints and tendon stress and strain were estimated. We compare data with that published for a generalized breed of canid, and other cursorial mammals such as the horse and hare. The pelvic limb of the racing greyhound had a relatively large volume of hip extensor muscle, which is likely to be required for power production. Per unit body mass, some pelvic limb muscles were relatively larger than those in less specialized canines, and many hip extensor muscles had longer fascicle lengths. It was estimated that substantial extensor moments could be created about the tarsus and hip of the greyhound allowing high power output and potential for rapid acceleration. The racing greyhound hence possesses substantial specializations for enhanced sprint performance. [source] Differentiating Human Bone from Animal Bone: A Review of Histological MethodsJOURNAL OF FORENSIC SCIENCES, Issue 2 2007Maria L. Hillier M.Sc. ABSTRACT: This review brings together a complex and extensive literature to address the question of whether it is possible to distinguish human from nonhuman bone using the histological appearance of cortical bone. The mammalian species included are rat, hare, badger, racoon dog, cat, dog, pig, cow, goat, sheep, deer, horse, water buffalo, bear, nonhuman primates, and human and are therefore not exhaustive, but cover those mammals that may contribute to a North American or Eurasian forensic assemblage. The review has demonstrated that differentiation of human from certain nonhuman species is possible, including small mammals exhibiting Haversian bone tissue and large mammals exhibiting plexiform bone tissue. Pig, cow, goat, sheep, horse, and water buffalo exhibit both plexiform and Haversian bone tissue and where only Haversian bone tissue exists in bone fragments, differentiation of these species from humans is not possible. Other primate Haversian bone tissue is also not distinguishable from humans. Where differentiation using Haversian bone tissue is undertaken, both the general microstructural appearance and measurements of histological structures should be applied. Haversian system diameter and Haversian canal diameter are the most optimal and diagnostic measurements to use. Haversian system density may be usefully applied to provide an upper and lower limit for humans. [source] Is the large size of the pinna of the ear of the European hare (Lepus europaeus) due to its role in thermoregulation or in anterior capital shock absorption?JOURNAL OF MORPHOLOGY, Issue 6 2010Philip Stott Abstract Large pinnae are characteristic of the Leporids, and the pinna is known to have a thermoregulatory role. Another role has been hypothesized for the pinna of Lepus spp., as a part of a suspensory system for the greater portion of the head, absorbing shock that might otherwise interfere with vision during high-speed locomotion. We compared the lengths of the pinnae of adult European hares Lepus europaeus from the source population in the cooler climate of England with those of the introduced population in the warmer climate of Australia, and we compared the lengths of the pinnae of hares that had grown in cooler weather with those that had grown in warmer weather. There were no significant differences between each of the comparisons, indicating that the size of the pinna is not determined by thermoregulatory requirements at rest. We compared the growth in length of the pinnae and the legs with growth in body mass, and growth in the mass of the pinnae with the masses of the head and the eyeballs, and found support for the suspension hypothesis. We suggest that the rapid growth of the pinna is because visual acuity is a function of absolute eye size, not relative eye size, yet juvenile hares are subject to the same predator pressure as adult hares, and equally need to maximize visual acuity while running at high speeds in dim light. We believe that the large size of the pinna is determined by its role in anterior capital suspension, not in thermoregulation. J. Morphol., 2010. © 2010 Wiley-Liss, Inc. [source] Natal dispersal of European hare in FranceJOURNAL OF ZOOLOGY, Issue 4 2007Y. Bray Abstract Dispersal is a fundamental process with wide-ranging evolutionary and management consequences. To date, natal dispersal has never been described for the polygynous-promiscuous European hare Lepus europaeus. Using telemetry, we investigated the natal dispersal pattern in two zones that differed in hunting pressure and hare density. We quantified both the natal dispersal rates and distances using 84 juvenile hares. We tested for the influence of several factors (age, sex, density and period of the year) on these two variables. Overall, the mean dispersal rate was 43% and the median natal dispersal distances were 209 m for philopatric hares and 1615 m for dispersers. The maximum distance moved was 17.35 km. Natal dispersal rates were higher in the hunting zone with less density for both males and females, but males dispersed more frequently than females in the two zones although females moved over longer distances. Natal dispersal occurred preferentially between 4 and 6 months of age. This very fine description of the natal dispersal pattern allowed us to make inferences about both the evolutionary and proximate causes of natal dispersal. We also advocate that more attention should be paid to dispersal in studies on hare dynamics and on the conception of hare management, because dispersal seems to be more common than previously thought. [source] The distribution of mountain hares Lepus timidus in Europe: a challenge from brown hares L. europaeus?MAMMAL REVIEW, Issue 1 2003CARL-GUSTAF THULIN ABSTRACT 1.,Throughout the most recent glacial period (Weichsel), the mountain hare Lepus timidus had a continuous distribution in the tundra habitat south of the ice-rim. When the ice retreated, mountain hares colonized deglaciated land, and spread over northern Europe. 2.,Since the Weichsel, the mountain hare's distribution in Europe has been gradually reduced and at present comprises Ireland and the Scottish Highlands, high altitudes in the Alps, isolated forests in eastern Poland, most of Fennoscandia and from the Baltic countries eastwards through Russia. Declines during the last century have been observed in Sweden and Russia. 3.,This review defines and evaluates causes for this gradual reduction and fragmentation of the mountain hare's distribution, with special focus on interactions with brown hares Lepus europaeus. The relative importance of diseases, predation, cultivation and interactions with other herbivores than brown hares are discussed. 4.,A plausible cause of the possible permanent disappearance of mountain hares in Europe appears to be exclusion by interspecific competition and hybridization with, and/or epidemic diseases mediated by, the congeneric brown hare. [source] The rise and fall of the mountain hare (Lepus timidus) during Pleistocene glaciations: expansion and retreat with hybridization in the Iberian PeninsulaMOLECULAR ECOLOGY, Issue 3 2007J. MELO-FERREIRA Abstract The climatic fluctuations during glaciations have affected differently arctic and temperate species. In the northern hemisphere, cooling periods induced the expansion of many arctic species to the south, while temperate species were forced to retract in southern refugia. Consequently, in some areas the alternation of these species set the conditions for competition and eventually hybridization. Hares in the Iberian Peninsula appear to illustrate this phenomenon. Populations of Iberian hare (Lepus granatensis), brown hare (Lepus europaeus) and broom hare (Lepus castroviejoi) in Northern Iberia harbour mitochondrial haplotypes from the mountain hare (Lepus timidus), a mainly boreal and arctic species presently absent from the peninsula. To understand the history of this past introgression we analysed sequence variation and geographical distribution of mitochondrial control region and cytochrome b haplotypes of L. timidus origin found in 378 specimens of these four species. Among 124 L. timidus from the Northern Palaearctic and the Alps we found substantial nucleotide diversity (2.3%) but little differentiation between populations. Based on the mismatch distribution of the L. timidus sequences, this could result from an expansion at a time of temperature decrease favourable to this arctic species. The nucleotide diversity of L. timidus mtDNA found in Iberian L. granatensis, L. europaeus and L. castroviejoi (183, 70 and 1 specimens, respectively) was of the same order as that in L. timidus over its range (1.9%), suggesting repeated introgression of multiple lineages. The structure of the coalescent of L. granatensis sequences indicates that hybridization with L. timidus was followed by expansion of the introgressed haplotypes, as expected during a replacement with competition, and occurred when temperatures started to rise, favouring the temperate species. Whether a similar scenario explains the introgression into Iberian L. europaeus remains unclear but it is possible that it hybridized with already introgressed L. granatensis. [source] Isolation and characterization of six polymorphic microsatellite loci in South African hares (Lepus saxatilis F. Cuvier, 1823 and Lepus capensis Linnaeus, 1758)MOLECULAR ECOLOGY RESOURCES, Issue 4 2002U. Kryger Abstract We have developed six novel, polymorphic microsatellite markers for the scrub hare, Lepus saxatilis. These markers have been tested for 150 scrub hares and 67 Cape hares from different localities across southern Africa. All six loci amplified consistently well and most were highly polymorphic. Four loci amplified consistently in five different leporid genera. The microsatellites presented here will be useful for phylogeographical studies in the scrub hare and other leporidae. [source] Winter browsing on Alaska feltleaf willow twigs improves leaf nutritional value for snowshoe hares in summerOIKOS, Issue 1 2003John P. Bryant In boreal forests, browsing by mammals on winter-dormant twigs increases leaf nitrogen, leaf greenness, and leaf size. This suggests browsing reduces competition among meristems for mineral nutrients, and in particular, competition for nitrogen. Winter browsing also reduces the shoot carbohydrate reserves used by leaves to produce condensed tannin. These effects of winter browsing are predicted to improve the nutritional value of leaves for mammals because they increase the mass of digestible nitrogen in leaves. This hypothesis was tested using Alaska feltleaf willow and the snowshoe hare as the experimental system. Six in vivo indicators of leaf nutritional quality were used to compare leaves from winter-browsed plants with leaves from unbrowsed plants. The indicators used were dry matter intake, nitrogen intake, condensed tannin intake, dry matter digestibility, apparent digestibility of nitrogen and nitrogen retention. The results obtained were in agreement with the above hypothesis. In early summer, at the time snowshoe hares and other northern herbivores reproduce, hares fed leaves from browsed plants consumed more nitrogen, digested more of the nitrogen they consumed, and retained more of the nitrogen they digested than did hares fed leaves from unbrowsed plants. The high nitrogen content and low tannin content of leaves from browsed plants may explain this browsing caused increase in leaf nutritional value. How these positive effects of winter browsing on snowshoe hare nutrition at the time of reproduction might affect hare population dynamics are briefly discussed. [source] The Fourteenth-Century Verse Novella Dis ist von dem Heselin: Eroticism, Social Discourse, and Ethical CriticismORBIS LITERARUM, Issue 4 2005Albrecht Classen Late-medieval German literature offers many highly intriguing examples of erotic narratives structured and motivated in the manner of the fabliaux and novelle. One of these maeren, Dis ist von dem Heselin, composed sometime around 1300, presents an account of a tryst between a naive peasant maid and a young knight who barters a hare for her love. The narrative lives from the charming contrast between this young woman's ignorance of the true meaning of the word minne, or ,courtly love,' and the moral decline of the nobility. Whereas she freely and openly grants her love to the knight and later tells everything to her mother, who severely punishes her for her seeming stupidity, the knight's noble fiancée proves to be highly cynical and morally untrustworthy. Mocking the peasant maid during the wedding celebration and emphasizing her own intelligent behavior in hiding her numerous sexual contacts with the family's chaplain, she deeply shocks her fiancé, who then quickly changes the marriage arrangements and takes the peasant maid as his wife. The maid triumphs over the noble lady because of her simplicity, trustworthiness, and true love for the knight. Her moral infraction is easily forgiven because of her ignorance and naiveté, whereas her highly respected competitor for the knight's hand loses because she knows nothing of true love and morality. [source] Capture,Recapture Estimation Using Finite Mixtures of Arbitrary DimensionBIOMETRICS, Issue 2 2010Richard Arnold Summary Reversible jump Markov chain Monte Carlo (RJMCMC) methods are used to fit Bayesian capture,recapture models incorporating heterogeneity in individuals and samples. Heterogeneity in capture probabilities comes from finite mixtures and/or fixed sample effects allowing for interactions. Estimation by RJMCMC allows automatic model selection and/or model averaging. Priors on the parameters stabilize the estimates and produce realistic credible intervals for population size for overparameterized models, in contrast to likelihood-based methods. To demonstrate the approach we analyze the standard Snowshoe hare and Cottontail rabbit data sets from ecology, a reliability testing data set. [source] | ||||||||||||||||||||||||||||||||||||||||||||||