111 research outputs found
Clutch size in Kittiwakes (Rissa tridactyla) on Lundy
Kittiwake (Rissa tridactyla) numbers on Lundy have been in decline for many decades. This decline is monitored using occupied nest counts and productivity data. More recently we have begun collecting data on clutch size at one colony on Lundy. Clutch size is a direct response by a bird to prevailing conditions. Therefore, clutch size data is potentially revealing in terms of what it tells us about Kittiwake response to factors such as food availability and predation risk, in a way that occupied nest counts and productivity data is not. Calculating clutch size is not straightforward for a colonial cliff nesting bird. In this paper we present a pilot study that has calculated clutch size, and then use that data to assess differences in clutch size across the colony with reference to possible differences in predation risk as a function of colony structure. We discuss the limitations of this pilot and also key aspects of the broader ecology, which we believe should also be monitored in order to better understand the plight of this seabird
Adult Kittiwake expelling chick from nesting ledge
On 17th June 2021, we witnessed an adult Kittiwake Rissa tridactyla expel a chick from its nesting ledge. The chick fell to its death. We made the observation during our annual monitoring of this species on Lundy. A scan of the colony at 12.13 hrs detected unusual movement in a two-chick nest. One chick, which we designated as the beta chick given its smaller size, was unusually positioned outside the nest away from the alpha chick and the adult, which both remained in the nest. We estimate that the beta chick was about 1–2 days old. The site was such that the floor of the ledge extended well behind the nest to a slightly overhanging back wall, and the chick was scrabbling against this back wall. At 12.25 hrs, in a rapid sequence of movements lasting only seconds, the beta chick turned and moved back in the direction of the nest. As it approached, it came between the adult and a side wall and was then grasped in the adult’s beak and expelled in an upward arc, falling into the sea below. No interactions between the alpha and beta were observed
Effects of canine-assisted intervention on the mental health of higher education students: a systematic review
The aim of this systematic review was to evaluate existing literature exploring the effects of canine assisted intervention (CAI) on the mental health of Higher Education (HE) students. A literature search was performed on 14th January 2021 for studies that investigated the effects of CAI on HE students. Thirty three papers (6093 participants) encompassing 37 studies were included in this review. Study design varied in research objective, intervention type, timing, procedure, and measures. The Effective Public Health Practice Project Quality Assessment Tool found studies ranged in quality from moderate (n=7) to weak (n=30). The review identified CAI has a positive effect on levels of anxiety and stress in HE students. Key limitations of the studies include confounding influences during the intervention as well as a lack of control groups and standardized measures. Furthermore, intervention and procedures ranged substantially in design and application making direct comparisons difficult. The authors conclude two main outcomes from the review. Firstly, CAI improves mental health in HE students, in particular anxiety and stress. Secondly, CAI has a social benefit, encouraging communication and a shared experience. However, a number of methodological limitations of the studies are identified and reviewed. To conclude, this systematic review reveals strong support for the use of CAI in HE students as a form of therapy
Dynamic processes happening during the evaporation of films of fusible materials
Optical waveguides on glass substrates are a promising area in their application in simple and cheap optoelectronic devices. As shown in [1], the highest refractive index is achieved during the formation of waveguides by oxidized film diffusion. However, realization of a number of electro-optical effects is restrained by probabilistic repeatability of wave guiding layers which holds down the development of optoelectronics [1-3]. This happens due to the fact that film formation in gas exchange mode isn't explored enough. One of the reasons of probabilistic repeatability of local thickness and film composition is dynamic processes which happen during the material evaporation. The regularities of evaporation, which were earlier found by Knudsen, Langmuir and other scientists for point sources, fail when it comes to the line where one material escape into another state. Most materials, which have three states - solid, liquid, gaseous - at ambient pressure heating, in vacuum, lose their liquid state partly or completely. Moreover, the film distribution over the substrate is quite unclear because of the poor study of molecular vapor flow and substrate interaction
Day-4 Myeloid Dendritic Cells Pulsed with Whole Tumor Lysate Are Highly Immunogenic and Elicit Potent Anti-Tumor Responses
“Day-7” myeloid DCs are commonly used in the clinic. However, there is a strong need to develop DCs faster that have the same potent immunostimulatory capacity as “Day-7” myeloid DCs and at the same time minimizing time, labor and cost of DC preparations. Although “2 days” DCs can elicit peptide-specific responses, they have not been demonstrated to engulf, process and present complex whole tumor lysates, which could be more convenient and personalized source of tumor antigens than defined peptides. In this preclinical study, we evaluated the T-cell stimulatory capacity of Day-2, Day-4, and Day-7 cultured monocyte-derived DCs loaded with SKOV3 cell whole lysate prepared by freeze-thaw or by UVB-irradiation followed by freeze-thaw, and matured with lipopolysaccharide (LPS) and interferon (IFN)-gamma. DCs were evaluated for antigen uptake, and following maturation with LPS and IFN-gamma, DCs were assessed for expression of CD80, CD40, CD86, ICAM-1 and CCR7, production of IL-12p70 and IP-10, and induction of tumor-specific T-cell responses. Day-4 and Day-7 DCs exhibited similar phagocytic abilities, which were superior to Day-2 DCs. Mature Day-7 DCs expressed the highest CD40 and ICAM-1, but mature Day-4 DCs produced the most IL-12p70 and IP-10. Importantly, Day-4 and Day-7 DCs derived from ovarian cancer patients stimulated equally strongly tumor-specific T-cell responses. This is the first study demonstrating the highly immunogenic and strong T-cell stimulatory properties of Day-4 myeloid DCs, and provided important preclinical data for rapid development of potent whole tumor lysate-loaded DC vaccines that are applicable to many tumor types
Comparison of peptide-major histocompatibility complex tetramers and dextramers for the identification of antigen-specific T cells
Fluorochrome-conjugated peptide–major histocompatibility complex (pMHC) multimers are widely used for flow cytometric visualization of antigen-specific T cells. The most common multimers, streptavidin–biotin-based ‘tetramers’, can be manufactured readily in the laboratory. Unfortunately, there are large differences between the threshold of T cell receptor (TCR) affinity required to capture pMHC tetramers from solution and that which is required for T cell activation. This disparity means that tetramers sometimes fail to stain antigen-specific T cells within a sample, an issue that is particularly problematic when staining tumour-specific, autoimmune or MHC class II-restricted T cells, which often display TCRs of low affinity for pMHC. Here, we compared optimized staining with tetramers and dextramers (dextran-based multimers), with the latter carrying greater numbers of both pMHC and fluorochrome per molecule. Most notably, we find that: (i) dextramers stain more brightly than tetramers; (ii) dextramers outperform tetramers when TCR–pMHC affinity is low; (iii) dextramers outperform tetramers with pMHC class II reagents where there is an absence of co-receptor stabilization; and (iv) dextramer sensitivity is enhanced further by specific protein kinase inhibition. Dextramers are compatible with current state-of-the-art flow cytometry platforms and will probably find particular utility in the fields of autoimmunity and cancer immunology
An autologous dendritic cell vaccine polarizes a Th-1 response which is tumoricidal to patient-derived breast cancer cells.
Breast cancer remains one of the leading causes of cancer-associated death worldwide. Conventional treatment is associated with substantial toxicity and suboptimal efficacy. We, therefore, developed and evaluated the in vitro efficacy of an autologous dendritic cell (DC) vaccine to treat breast cancer. We recruited 12 female patients with stage 1, 2, or 3 breast cancer and matured their DCs with autologous tumour-specific lysate, a toll-like receptor (TLR)-3 and 7/8 agonist, and an interferon-containing cocktail. The efficacy of the vaccine was evaluated by its ability to elicit a cytotoxic T-lymphocyte response to autologous breast cancer cells in vitro. Matured DCs (≥ 60% upregulation of CD80, CD86, CD83, and CCR7) produced high levels of the Th1 effector cytokine, IL12-p70 (1.2 ng/ml; p < 0.0001), compared to DCs pulsed with tumour lysate, or matured with an interferon-containing cocktail alone. We further showed that matured DCs enhance antigen-specific CD8 + T-cell responses to HER-2 (4.5%; p < 0.005) and MUC-1 (19%; p < 0.05) tetramers. The mature DCs could elicit a robust and dose-dependent antigen-specific cytotoxic T-lymphocyte response (65%) which was tumoricidal to autologous breast cancer cells in vitro compared to T-lymphocytes that were primed with autologous lysate loaded-DCs (p < 0.005). Lastly, we showed that the mature DCs post-cryopreservation maintained high viability, maintained their mature phenotype, and remained free of endotoxins or mycoplasma. We have developed a DC vaccine that is cytotoxic to autologous breast cancer cells in vitro. The tools and technology generated here will now be applied to a phase I/IIa clinical trial
Neue trifokale IOL-Plattform mit unterschiedlicher Lichtverteilung: Ergebnisse zur postoperativen Zufriedenheit
Neue trifokale IOL-Plattform mit unterschiedlicher Lichtverteilung: Ergebnisse zum postoperativen Sehbereich
Obesity and loneliness. Findings from a longitudinal population‐based study in the second half of life in Germany
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