133 research outputs found

    Oysters and catfish: resource exploitation at Rollins Shell Ring, Ft. George Island, Florida

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    Detailed faunal analyses were conducted on two major subsistence resources, oysters and marine catfish, at Rollins Shell Ring, a Late Archaic (5000 – 3000 B.P.) site on the northeast coast of Florida. The focus of this investigation was on resource exploitation, and, specifically, whether there was evidence that oysters from this site were over-exploited. Three units from previous excavations at the site were selected for analysis, and represent the span of occupation recorded for this site. Measurements were obtained from oysters to determine habitat, and, along with shell height, were compared across time for any changes in the pattern of exploitation that would indicate over-exploitation. Marine catfish otoliths were used to provide seasonal data for oyster harvesting, as well as information on fish ages and harvesting of this resource. My analysis revealed that the majority of oysters used in the construction of the main shell ring, ringlets, and other structures at this site were harvested from the same habitat. While there were differences in oyster habitat exploitation and shell height between samples, the difference was attributed to the variability of oyster habitats exploited and shell height in the earliest sample of the analysis, Test Unit 10, and in the latest sample, Test Unit 2; there was less variability noted in oyster habitat and shell height for the middle activity period recorded at the site, Test Unit 12c. Further results indicated a seasonal preference for exploitation of both oyster and marine catfish in warm water temperatures, and that oyster resources did not appear to be under stress during the period of activity recorded for the site. These data suggest that it is unlikely that over-exploitation of oysters played a role in permanent site abandonment

    Julie-la-terreur se meurt

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    Traitement simultané des nitrates et du méthane des sites d'enfouissement à l'aide de bactéries méthanotrophes par biofiltration

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    Au QuĂ©bec, l'enfouissement est la technique la plus rĂ©pandue pour l'Ă©limination des matiĂšres rĂ©siduelles. Bien qu'elle soit simple et Ă©conomique, elle entraĂźne diffĂ©rentes problĂ©matiques, dont la production de lixiviats, des liquides trĂšs chargĂ©s en contaminants, et de gaz d'enfouissement contribuant Ă  l'Ă©mission de gaz Ă  effet de serre. Chez Investissement QuĂ©bec - CRIQ (IQ-CRIQ), la biofiltration mĂ©thanotrophe a Ă©tĂ© Ă©tudiĂ©e dans les derniĂšres annĂ©es pour le traitement combinĂ© de ces deux sources de polluants. Si cette technologie a montrĂ© une bonne capacitĂ© Ă  traiter le mĂ©thane (CH₄) prĂ©sent dans les gaz d'enfouissement, tout en assimilant de l'azote des lixiviats, la capacitĂ© du systĂšme biologique Ă  rĂ©sister aux fluctuations saisonniĂšres de tempĂ©rature peut ĂȘtre questionnĂ©e. L'objectif principal est donc de vĂ©rifier si le caractĂšre exothermique de la rĂ©action d'oxydation du CH₄ par les bactĂ©ries mĂ©thanotrophes permet de maintenir l'activitĂ© biologique au sein du biofiltre et donc la capacitĂ© Ă©puratoire du CH₄ et de l'azote nitrate (NO₃-) des lixiviats en pĂ©riode hivernale. Pour ce faire, un montage expĂ©rimental comprenant quatre biofiltres avec un garnissage organique a Ă©tĂ© alimentĂ© avec des lixiviats prĂ©traitĂ©s provenant d'un site d'enfouissement et un mĂ©lange synthĂ©tique de gaz composĂ© de gaz naturel et d'air. Des isolants en urĂ©thane et une chambre rĂ©frigĂ©rĂ©e ont Ă©tĂ© utilisĂ©s afin de reproduire les conditions hivernales sur le terrain d'un biofiltre enfoui, soit une tempĂ©rature avoisinant les 4 °C. En ce sens, la tempĂ©rature d'alimentation liquide a aussi Ă©tĂ© diminuĂ©e Ă  4 °C pour deux des quatre biofiltres. L'effet d'une charge en CH₄ plus importante sur le traitement a aussi Ă©tĂ© explorĂ©. Durant les expĂ©rimentations qui se sont Ă©tendues sur environ 300 jours, les gaz (CH₄, CO₂, N₂O entre autres) et les liquides (NO₃-, NO₂-, NH₄+, pH entre autres) ont Ă©tĂ© analysĂ©s deux Ă  trois fois par semaine et la tempĂ©rature interne des rĂ©acteurs a Ă©tĂ© suivie en continu Ă  l'aide de capteurs. Les expĂ©rimentations ont permis de montrer que le maintien du traitement Ă©tait possible mĂȘme avec une baisse de la tempĂ©rature du liquide d'alimentation : une capacitĂ© d'Ă©limination de 98 Ă  112 gCH₄/mÂł/j et de 2,6 Ă  3,2 gN-NO₃-/mÂł/j a Ă©tĂ© observĂ©e pour le biofiltre Ă  tempĂ©rature ambiante (environ 21 °C) alimentĂ© avec un lixiviat Ă  4 °C alors qu'elle a Ă©tĂ© de 113 gCH₄/mÂł/j et de 4,4 gN-NO₃-/mÂł/j pour le biofiltre tĂ©moin (tempĂ©rature ambiante et d'alimentation liquide Ă  environ 21 °C). Cependant, le biofiltre alimentĂ© avec des lixiviats Ă  4 °C et placĂ© dans un environnement avec une tempĂ©rature ambiante Ă  4 °C a vu ses capacitĂ©s Ă  traiter le CH₄ et le NO₃- devenir nulles lors du changement drastique de tempĂ©rature. Finalement, le biofiltre alimentĂ© avec une concentration plus Ă©levĂ©e en CH₄ n'a pas Ă©tĂ© en mesure de traiter davantage de contaminants, ce qui laisse croire qu'il pourrait y avoir un dĂ©balancement entre le CH₄, les NO₃- et les autres nutriments essentiels ou encore la prĂ©sence d'inhibiteurs au sein du biofiltre. Une difficultĂ© des gaz Ă  pĂ©nĂ©trer le biofilm a aussi pu limiter la capacitĂ© d'oxydation et donc l'enlĂšvement des NO₃-. Bien que des incertitudes persistent, les rĂ©sultats obtenus montrent bien un potentiel de maintien des capacitĂ©s Ă©puratoires par les mĂ©thanotrophes en pĂ©riode froide d'opĂ©ration

    St. John\u27s Wort inhibits adipocyte differentiation and induces insulin resistance in adipocytes

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    Adipocytes are insulin sensitive cells that play a major role in energy homeostasis. Obesity is the primary disease of fat cells and a major risk factor for the development of Type II diabetes, cardiovascular disease, and metabolic syndrome. Obesity and its related disorders result in dysregulation of the mechanisms that control adipocyte gene expression and function. To identify potential novel therapeutic modulators of adipocytes, we screened 425 botanical extracts for their ability to modulate adipogenesis and insulin sensitivity. We observed that less than 2% of the extracts had substantial effects on adipocyte differentiation of 3T3-L1 cells. Two of the botanical extracts that inhibited adipogenesis were extracts from St. John\u27s Wort (SJW). Our studies revealed that leaf and flower, but not root, extracts isolated from SJW inhibited adipogenesis as judged by examining PPARγ and adiponectin levels. We also examined the effects of these SJW extracts on insulin sensitivity in mature 3T3-L1 adipocytes. Both leaf and flower extracts isolated from SJW substantially inhibited insulin sensitive glucose uptake. The specificity of the observed effects was demonstrated by showing that treatment with SJW flower extract resulted in a time and dose dependent inhibition of insulin stimulated glucose uptake. SJW is commonly used in the treatment of depression. However, our studies have revealed that SJW may have a negative impact on adipocyte related diseases by limiting differentiation of preadipocytes and significantly inducing insulin resistance in mature fat cells. © 2009 Elsevier Inc. All rights reserved

    Impact of nutritional labelling on 10-d energy intake, appetite perceptions and attitudes towards food

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    The purpose of this study was to investigate the impact of nutritional labelling on energy intake, appetite perceptions and attitudes towards food. During a 10-d period, seventy normal-weight (BMI<25 kg/m2) and seventy-one obese women (BMI= 30 kg/m2) were given three meals per d under ad libitum conditions. Participants were randomly assigned to one of three experimental labelling groups in which the only difference was the label posted on lunch meal entrĂ©e: (1) low-fat label, (2) energy label (energy content of the entrĂ©e and average daily needs) and (3) no label (control). Average energy intake was calculated by weighing all foods before v. after daily consumption. Hunger and fullness perceptions were rated on visual analogue scales immediately before and after each meal. Satiety efficiency was assessed through the calculation of the satiety quotient (SQ). The appreciation and perceived healthiness of the lunch entrĂ©es were rated on eight-point Likert scales. There was no difference in energy intake, SQ and attitudes towards food between the three labelling groups. Fasting hunger perception was higher in the low-fat label group compared with the two others groups (P =0·0037). No interactions between labelling groups and BMI categories were observed. In conclusion, although labelling does not seem to influence energy intake, a low-fat label may increase women’s fasting hunger perceptions compared with an energy label or no label

    A New Methodology for Quantification of Alternatively Spliced Exons Reveals a Highly Tissue-Specific Expression Pattern of WNK1 Isoforms

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    Mutations in the WNK1 gene, encoding a serine-threonine kinase of the WNK (With No lysine (K)) family, have been implicated in two rare human diseases, Familial Hyperkalemic Hypertension (FHHt) and Hereditary Sensory and Autonomic Neuropathy type 2 (HSAN2). Alternative promoters give rise to a ubiquitous isoform, L-WNK1, and a kidney-specific isoform, KS-WNK1. Several other isoforms are generated through alternative splicing of exons 9, 11 and 12 but their precise tissue distribution is not known. Two additional exons, 8b and HSN2, involved in HSAN2, are thought to be specifically expressed in the nervous system. The purpose of this study was to establish an exhaustive description of all WNK1 isoforms and to quantify their relative level of expression in a panel of human and mouse tissues and in mouse nephron segments. For the latter purpose, we developed a new methodology allowing the determination of the proportions of the different isoforms generated by alternative splicing. Our results evidenced a striking tissue-specific distribution of the different isoforms and the unexpected presence of exon HSN2 in many tissues other than the nervous system. We also found exon 26 to be alternatively spliced in human and identified two new exons, 26a and 26b, within intron 26, specifically expressed in nervous tissues both in humans and mice. WNK1 should therefore no longer be designated as a 28- but as a 32-exon gene, with 8 of them - 8b, HSN2, 9, 11, 12, 26, 26a and 26b - alternatively spliced in a tissue-specific manner. These tissue-specific isoforms must be considered when studying the different roles of this ubiquitous kinase

    How Tightly Linked Are Pericopsis elata (Fabaceae) Patches to Anthropogenic Disturbances in Southeastern Cameroon?

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    peer reviewedWhile most past studies have emphasized the relationships between specific forest stands and edaphic factors, recent observations in Central African moist forests suggested that an increase of slash-and-burn agriculture since 3000–2000 BP (Before Present) could be the main driver of the persistence of light-demanding tree species. In order to examine anthropogenic factors in the persistence of such populations, our study focused on Pericopsis elata, an endangered clustered timber species. We used a multidisciplinary approach comprised of botanical, anthracological and archaeobotanical investigations to compare P. elata patches with surrounding stands of mixed forest vegetation (“out-zones”). Charcoal samples were found in both zones, but were significantly more abundant in the soils of patches. Eleven groups of taxa were identified from the charcoals, most of them also present in the current vegetation. Potsherds were detected only inside P. elata patches and at different soil depths, suggesting a long human presence from at least 2150 to 195 BP, as revealed by our charcoal radiocarbon dating. We conclude that current P. elata patches most likely result from shifting cultivation that occurred ca. two centuries ago. The implications of our findings for the dynamics and management of light-demanding tree species are discussed

    UNBOUND

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    UNBOUND showcases the graduating class from the fashion design school at Fanshawe College. We are pleased to present Unbound 2017! Our 11th Unbound theme embraces the concept of Craft and Machine , a blend of couturier techniques with technology. Unbound describes the creative spirit and achievements of our eighteen emerging Canadian fashion designers. Unbound 2017 is a professional collaboration between Fanshawe College, community and professionals in the fashion industry. As you turn the pages, admire their accomplishments - the results of three years of passion, hard work, and dedication.https://first.fanshawec.ca/famd_design_fashiondesign_unbound/1004/thumbnail.jp
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