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141.
ABSTRACT

Working memory (WM) plays a critical role in the execution of a wide variety of cognitive tasks and predicts academic success. This study was designed to compare the impact of the presence of a dog or a person, and physical contact with them, on the performance of a WM task. It also exam- ined whether the impact differed for two dogs, and whether these factors im- pacted arousal during the WM task. College students (n=31, aged 18–23 years) performed a WM task in five counterbalanced conditions; dog-touch, dog-no-touch, person-touch, person-no-touch, and alone. Participants were randomly assigned to one of two dogs; Miniature Poodle (n=16) or Border Collie (n=15). The WM task involved replicating increasingly complicated se- quences of colored lights by touching them on an iPad®. Linear mixed model analyses revealed there was a significant interaction between collaborator and touch (p=0.05); best WM scores occurred without touch with either the per- son or the dog present, and worst WM scores occurred when the participant was touching a dog. Analyzing WM test during the dog conditions, touch (p=0.027) and dog breed (p=0.042) contributed independently to it; task completion was worse when the poodle was present and better without touch. Physiological measures [heart rate (HR) and heart rate variability] during the ex- periment indicated that the WM task was physiologically arousing (p<0.001) compared with listening, and HR was higher when touching a person than a dog during the task (p<0.046). These results are consistent with facilitation of performance by the presence of an observer. If there is a beneficial effect on cognition from a dog, physical contact with the dog might not be a necessary component. Aspects of the dog (e.g., breed) are also likely factors in WM task performance. This study highlights the importance of situational characteristics in studies evaluating the impact of companion animals.  相似文献   
142.
《Ostrich》2013,84(3):271-272
The Berlese funnel method, and its variations, is commonly used for the extraction of arthropods from various substrates such as nest material. However, little is known about its effectivity in extracting ectoparasites from penguin nests. This study aimed to assess the efficacy of a modified Berlese funnel method in extracting ectoparasites from African Penguin Spheniscus demersus nests and to determine differences in extraction capacity across parasite taxa and life stages. African Penguin nests (n = 278) were sampled at five penguin colonies along the south-west coast of South Africa in 2017. Nest samples were subjected to a modified Berlese funnel method with naphthalene as a repellent. Thereafter, all remaining ectoparasites were removed by hand sorting. Ectoparasite abundance was positively correlated between the two extraction methods (Spearman’s r = 0.73–0.89). Compared to total counts, flea (combined life stages and larvae) and total ectoparasite abundance and prevalence were significantly lower with the modified Berlese funnel method. In addition, adult flea and tick prevalence (but not abundance) was significantly lower with the modified Berlese funnel method compared with total counts. The modified Berlese funnel method fails as a quantitative method and can only provide a crude indication of the incidence of ectoparasites in penguin nests.  相似文献   
143.
Giardia lamblia is recognized as one of the most prevalent parasites in dogs. The present study aimed to establish a loop-mediated isothermal amplification (LAMP) assay for rapid and specific detection of G. lamblia from dogs. The fecal samples were collected and prepared for microscopic analysis, and then the genomic DNA was extracted directly from purified cysts. The concentration of DNA samples of G. lamblia were diluted by 10-fold serially ranging from 10-1 to 10-5 ng/µl for LAMP and PCR assays. The LAMP assay allows the amplification to be finished within 60 min under isothermal conditions of 63℃ by employing 6 oligonucleotide primers designed based on G. lamblia elongation factor 1 alpha (EF1α) gene sequence. Our tests showed that the specific amplification products were obtained only with G. lamblia, while no amplification products were detected with DNA of other related protozoans. Sensitivity evaluation indicated that the LAMP assay was sensitive 10 times more than PCR. It is concluded that LAMP is a rapid, highly sensitive and specific DNA amplification technique for detection of G. lamblia, which has implications for effective control and prevention of giardiasis.  相似文献   
144.
This study describes the first record of Bourgelatia diducta (Nematoda: Chabertiidae) from wild boars in the Republic of Korea (=South Korea). Gastrointestinal tracts of 87 Korean wild boars (Sus scrofa coreanus) hunted in mountains in the south-western part of South Korea between 2009 and 2012 were examined for their visceral helminths. B. diducta, as identified by morphological characteristics of the head and tail, were recovered from the large intestine of 47 (54%) wild boars. The average length of adult female worms was 11.3±0.87 mm and the thickest part of the body measured 0.54±0.04 mm in maximum width, while those of males were 9.8±0.72 and 0.45±0.03 mm, respectively. The characteristic J-shaped type II ovejector was observed in females, and the type II dorsal ray with 2 rami on each side of the median fissure was uniquely seen in males. The buccal capsule was small, relatively thin-walled, cylindrical, very short, and ring-shaped. The externodorsal ray arose from a common stem with the dorsal ray. The cervical groove was absent. The anterior extremity was equipped with 20-22 external corona radiata, 4 cephalic papillae and 2 lateral amphids around the mouth. The eggs were 66.0×38.9 µm in average size. By the present study, B. diducta (Nematoda: Chabertiidae) is recorded for the first time in South Korea. Additionally, morphological characteristics and identification keys provided in the present study will be helpful in the faunistic or taxonomic studies for strongylid nematodes related.  相似文献   
145.
The geographical distribution, population structure and pollination ecology are key aspects in the conservation and management of rare orchids. Here, we address these aspects and the main threats affecting the endangered Cuban orchid Broughtonia cubensis. This rewardless orchid is self‐compatible, but pollinator dependent. However, seed production can be negatively affected by insect‐mediated selfing. Three species of small bee (genera Ceratina and Lasioglossum) act as pollinators. As in the case of other nectarless orchids, we detected two species of plant producing large amounts of nectar in the area, the floral morphology of which closely resembles that of B. cubensis. The simultaneous flowering of these species could positively affect the reproductive success of B. cubensis. Nonetheless, the fitness of this orchid in natural conditions is low, possibly related to strong pollen limitation. To the problems arising from reduced fitness is added the fact that its historical distribution range has been greatly reduced in recent years. Throughout this study, we have detected dramatic reductions in the population sizes, in some cases as a result of human plundering, but also as a consequence of hurricanes. Based on the results of this study, we propose some guidelines to manage and conserve this orchid. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 345–357.  相似文献   
146.
In this ethnobotanical study, the authors provide the first quantitative analysis of the use of wild edible plants in Estonia, describing the domains and assessing the food importance of different species. The information was collected using free‐listing written questionnaires and concerned plants used by the respondents in their childhood. As part of a major study, this article covers the responses of professionals with some botanical education at vocational or university level, to ensure the greatest possible reliability without using voucher specimens. Fifty‐eight respondents provided information on the use of 137 plant taxa, corresponding to approximately 6% of the native and naturalized vascular plants of Estonia. According to use frequency, the most typical wild food plant of Estonia is a fruit, eaten raw as a snack. The results clearly signal that the majority of famine and food shortage plants had already been forgotten by the end of the 20th century, but new plants have been introduced as green vegetables for making salads. Despite changes in the nomenclature of the plants, the use of wild food plants in Estonia was still thriving at the turn of the 20th century, covering many domains already forgotten in urbanized modern Europe. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 239–253.  相似文献   
147.
Early research on black racial identity development cautioned that close relationships with whites signalled an alienation from blackness and a subconscious acceptance that ‘white is right’. These assumptions mirrored popular media and political discourse suggesting that romantic relationships outside of one's racial group reflect a devalued or inauthentic racial self. More recent scholarly research presents a mixed picture about the role of interracial intimacy on black racial identities. Using in-depth qualitative narratives with forty-two interracially partnered African Americans, this article explores whether interracial intimacy recasts the meaning or intensity of black racial identities. Findings affirm that black racial identities are heterogeneous – some partners experienced blackness as a central, fundamental identity while others possessed ambivalent attachments to blackness. Across these experiences, however, adult interracial intimacy had at most an incremental influence on racial identity. Interracial contact during adolescence was far more influential because it allowed blacks to develop dimensions of white cultural identity.  相似文献   
148.
An investigation of population structure and ecology of the African buffalo (Syncerus caffer Sparrman, 1779) was carried out in the Chebera Churchura National Park, Ethiopia during the wet and dry seasons of 2005–2006. Sample counts of African buffaloes were carried out in an area of 1,215 km2. The estimated population of buffalo was 2,617 individuals. Males comprised 35.0%, while females 52.8% of the population. The remaining 12% of the population was young of both sexes and of all ages of unknown sex. It was difficult to categorize the young into male and female in the field, as their primary sexual characteristics were not easily visible. Male to female sex ratio was 1.00 : 1.51. Age structure was dominated by adults, which constituted 72.06% of the total population. Subadults comprised 22.02%, and young accounted for 5.9% of the population. Larger herds of up to 27 individuals were observed during the wet season and smaller herds of eight individuals during the dry season. The mean herd size during wet and dry seasons was 24.81 and 7.77, respectively. The African buffaloes were distributed in four habitat types such as grasslands, woodlands, montane forests and riverine habitat in the study area. They were observed more in the riverine vegetation types during the dry season. Relative abundance of food resources, green vegetation cover and water availability in the area were the major factors governing their distribution in the present study area. They spent a greater proportion of the time in feeding and resting/ruminating activities. On the average, 49.7% of the daytime was spent in feeding, and 38.75% of the day on resting (lying down and standing). Morning and the late afternoon activity peaks were more pronounced during the dry season than the wet season.  相似文献   
149.
By describing the everyday lives of African migrant mothers and their children in Morocco, this paper highlights how migration and ‘immobility’ in so-called ‘transit countries’ are gendering and gendered experiences. Relying on migrants' narratives, the paper demonstrates how migrants' transitions to motherhood create both specific and gendered spaces for agency and particular and gendered constraints upon agency that shape women migrants' mobility dynamics in space and time.  相似文献   
150.
This paper contextualizes racial and ethnic identities in shaping African women’s work lives in the USA. While the literature on black immigrant groups has posited that ethnic identities are often deployed to shield black immigrants from racism, my findings indicate that for a group of African women, their racial and ethnic identities are viewed as potential sources of discrimination. As black immigrant women from middle-class backgrounds in their home countries, they also articulate experiences with racism and downward social and occupational mobility. Accounting for how race and ethnicity intersect in the lives of black immigrant groups can nuance our understanding of racial identities and highlight diversity in experiences among national and regional groups. Focusing on particular health-care settings further suggests the importance of professional contexts in shaping the identity formations of recent black immigrants.  相似文献   
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