Diurnal and nocturnal temperatures for Atlantic salmon postsmolts (Salmo salar L.) during their early marine life

Data storage tags (DSTs) were applied to Atlantic salmon (Salmo salar L.) smolts during their seaward migration in the spring of 2002 at a fish counting fence on Campbellton River, Newfoundland. Our objectives were to discover whether or not salmon smolts could carry DSTs and survive, whether or not useful data on thermal habitat could be obtained and interpreted, and whether or not salmon smolts moved vertically in the water column. Data were downloaded from 15 of the recovered tags and revealed the hourly water temperatures experienced by the fish for periods of 3 to 71 days. The data on the DSTs were analyzed for temperature patterns in relation to migration behavior and diurnal movement of the fish. While in the sea, the DSTs recorded night temperatures of 12.5°C, which were higher than day temperatures of 11.6°C; the record from moored recorders, however, indicated that sea temperatures actually declined at night. It is hypothesized that posts-molts avoid avian predators during daylight hours by positioning themselves deeper in the water column and that they were pursuing prey during the deeper vertical descents or ascents noted during the periods of more rapid changes in temperature

Competition between co-occurring invasive and native consumers switches between habitats

1.The introduction of a non‐native species frequently has adverse direct effects on native species. The underlying mechanisms, however, often remain unclear, in particular where native and invasive species are taxonomically similar. 2.We found evidence of direct competitive interactions between a globally distributed invasive species (the Pacific oyster, Magallana gigas) and its native counterpart (the European oyster, Ostrea edulis). We also discovered that the competitive outcome differed between different habitat types and orientation by identifying context‐dependent responses driven by environmental conditions and stress (i.e. intertidal compared to subtidal habitats; and vertical versus horizontal substratum). This is particularly important because the European oyster is threatened, or in decline, throughout most of its range and restoration efforts are underway in many regions. 3.We combined experimental manipulations and stable isotope analysis (SIA) to identify the direct effects of competition and the mechanisms by which the invasive and native species compete. We identified negative effects of the invasive species on the native oyster but these were limited to the subtidal habitat (lower stress environment) and determined by substratum orientation (habitat structure). Crucially, we found that effects of the invasive species on the native species were not always negative and under certain conditions (e.g. on vertical substrata) were positive. Shifts in isotopic niches of both species when co‐occurring, alongside mixing models, indicate that exploitative competition for food is most likely to underpin niche partitioning between both species. 4.We have identified different foraging strategies under different contexts and our findings highlight the importance of exploitative competition as a driving mechanism behind the co‐occurrence of two seemingly functionally similar consumers. The combination of experimental manipulations with SIA is a powerful tool and we illustrate how this approach should be incorporated, into multiple environmental contexts at appropriate scales, to more accurately predict impacts of the spread of invasive species on native communities

Small Mammal Community Associations and Habitat Use at Pea Ridge National Military Park, Benton County, Arkansas

Juniperus virginiana L. (Eastern Red Cedar) is a fire-intolerant tree species that has been invading and altering grassland ecosystems throughout the American Great Plains and Midwest. To see how Eastern Red Cedar encroachment affects small mammal communities, we surveyed small mammals using mark-recapture methods in Eastern Red Cedar forest and 5 other habitats common to the Ozark region. Additionally, we compared the microhabitat use of presumed juniper obligate Peromyscus attwateri J.A. Allen (Texas Mouse) and its conspecific P. leucopus Rafinesque (White-Footed Mouse). We ran over 7000 trap-nights and found that the small mammal species composition in Eastern Red Cedar was comparable to local mixed oak forests but lower than warm-season grasslands and oldfields. We encountered no small mammal species endemic to Eastern Red Cedar forest. Texas Mice were using Eastern Red Cedar sites more than oak and used areas with high vertical structure while White-Footed Mice showed a slightly increased use of areas with high litter ground cover

Purification, immunogenicity and protective potency of the F1 antigen from <i>Yersinia pestis</i>

Yersinia pestis, an organism endemic in much of the world, is the causative agent of pneumonic and bubonic plague. The disease is severe with a high mortality rate. Most plague vaccines are formalised whole cells, which give limited and short-lived immunity. An acellular vaccine could prove to be more effective than using killed whole cells, without the associated side effects. The 17.5kDa F1 antigen of Y. pestis has been shown to be immunogenic and protective in mice (Simpson et at., 1990) and therefore it might be a suitable component of an acellular vaccine. In this study, the conditions for the production and purification of Fl from culture of Y. pestis were examined with a view to increasing the yield of F1 antigen. The optimal conditions were to grow Y. pestis MRE 1447 in a chemically defined medium at pH7.4 for 48h at 37°C and these conditions were transferred to a 25-litre fermenter for the larger-scale production of F1 antigen. Typically, 40mg of F1 antigen of ≥90% purity was obtained from 1L of culture supernatant. The purified F1 was characterised using biochemical, structural and immunological methods to confirm the integrity of the purified antigen. Immunological methods using anti-F1 monoclonal and polyclonal antibody identified the purified antigen as F1. Structural studies on the glycosylation of the protein showed that no post-translational glycosylation of the protein could be detected by the methods used in this study. The caf1 sequence was successfully cloned into Escherichia coli to produce a recombinant F1 antigen. This recombinant antigen proved to be both immunogenic and protective but yields of recombinant protein were consistently low. Purified culture-derived native F1 and a recombinant V antigen (produced at CBD, DERA) were used to assess controlled-release vaccine delivery systems in poly(lactideco-glycolide) PLG micro spheres and liposomes. Recombinant V was used in addition to F1 to assess a combination subunit vaccine with F1 given alone as an acellular vaccine. F1 antigen encapsulated in PLG microspheres induced high serum antibody titres when injected i.p. in mice; mucosal IgA was also detected. Mice immunised with Fl in Alhydrogel or PLG micro spheres were protected against sub-cutaneous challenge with Y. pestis. F1 antigen surface-labeled onto liposome vesicles stimulated high serum titres in Balb/c mice; a mucosal response was also induced and mice were protected against subcutaneous challenge with up to 1 x 105 organisms. This strongly indicated that immunising with F1 formulated in PLG micro spheres and liposomes induced a potent immune response and that protection was achieved after only one dose. However, increased protection was observed when a combination vaccine of F1 and rV was administered in PLG microspheres, liposomes or Alhydrogel given in multiple doses. The efficacy of different delivery routes against sub-cutaneous Y. pestis challenge was also investigated. Administration by the i.p. route gave consistent protection against subcutaneous plague challenge. The i.n. route also proved effective for both PLG microspheres and liposomes when multiple doses were used. Oral delivery failed to give adequate protection against sub-cutaneous infection, even after multiple doses

Masculinity, Social Support and Sense of Community : The Mens Group Experience

Recently, there has been increased attention in understanding factors that influence men\u27s health and wellbeing. This paper examines men\u27s wellbeing and the male crisis\u27 in Western Society. A brief historical overview is outlined to illustrate how social change has impacted on male gender roles. Men\u27s role in society is discussed in relation to their response to feminism, and gender identity and the concept of masculinity as a social construction is outlined. Factors such as changing gender roles and subsequent role confusion are addressed in connection with men\u27s health. This paper will then examine men\u27s social support systems, with a focus on men\u27s groups. The role and purpose of these groups is discussed as an alternative form of social support for men. It is suggested that men\u27s support groups may be understood as a relational community with a common group narrative. For example, a community narrative shapes the social identities of members, and the exchange of personal stories facilitates personal change. Hence, previous research on psychological sense of community (PSC) and narrative theory are reviewed to illustrate how individual identity is embedded in the community context, and is facilitated by community and personal narratives. The process of identity transformation is discussed as an outcome from involvement in men\u27s groups. Finally, qualitative research is discussed and future directions in research are outlined

CONSTITUTIONAL LAW-INTERSTATE PRIVILEGES AND IMMUNITIES-STATE\u27S PROPRIETARY INTEREST IN ITS NATURAL RESOURCES

Plaintiffs, non-residents of South Carolina, brought action to enjoin enforcement of the South Carolina statutes regulating fishing within the three mile maritime belt. The statutes imposed an annual license fee on boats engaged in shrimp fishing of $25.00, if owned by residents, and of$2500.00, if owned by non-residents; it exacted a tax of 1/8 cent per pound on green shrimp taken or canned, shucked or shipped for market, and it required all licensed boats to unload, pack and properly stamp their catch in South Carolina before shipment to another state. Plaintiffs who fish within and beyond the three-mile limit contended that the statutes were void on the ground, among others, that they make an arbitrary discrimination between residents and non-residents in violation of the privileges and immunities clause, Article IV, section 2 of the United States Constitution, and that they impose a burden on interstate commerce in violation of sections 8 and 10 of Article 1. Held, injunction denied and case dismissed. The South Carolina statutes do not go beyond the power of a state to regulate the taking of fish or animals ferae naturae, the ownership of which is in the state for the benefit of its inhabitants. Toomer v. Witsell, (D.C. S.C. 1947) 73 F. Supp. 371

COVID-19 Health Evidence Summary No.45

This is a weekly summary of the daily COVID-19 health evidence summary (HES) which are based on 3 hours of desk-based research each day. The summary is not intended to be a comprehensive summary of available evidence on COVID-19 but aims to make original documents easily accessible to decision makers which, if relevant to them, they should go to before making decisions. This summary covers publications on Clinical characteristics and management; Epidemiology and modelling ; Infection Prevention and Control; Testing; Therapeutics; Vaccines; Indirect impact of COVID-19; Comments, Editorials, Opinions, Blogs, News; Guidelines, Statements & Tools; Dashboards & Trackers; C19 Resource Hubs; and Online learning & events