Estrous cycle-dependent changes of Fas expression in the bovine corpus luteum: influence of keratin 8/18 intermediate filaments and cytokines

Background Fas expression and Fas-induced apoptosis are mechanisms attributed to the selective destruction of cells of the corpus luteum (CL) during luteal regression. In certain cell-types, sensitivity to these death-inducing mechanisms is due to the loss or cleavage of keratin-containing intermediate filaments. Specifically, keratin 8/18 (K8/K18) filaments are hypothesized to influence cell death in part by regulating Fas expression at the cell surface. Methods Here, Fas expression on bovine luteal cells was quantified by flow cytometry during the early (Day 5, postovulation) and late stages (Days 16–18, postovulation) of CL function, and the relationship between Fas expression, K8/K18 filament expression and cytokine-induced cell death in vitro was evaluated. Results Both total and cell surface expression of Fas on luteal cells was greater for early versus late stage bovine CL (89% vs. 44% of cells for total Fas; 65% vs.18% of cells for cell surface Fas; respectively, P0.05, n=4 CL/stage), despite evidence these conditions increased Fas expression on HepG2 cells (P0.05) or stage of CL (P\u3e0.05, n= 4 CL/stage) on this outcome. Conclusion In conclusion, we rejected our null hypothesis that the cell surface expression of Fas does not differ between luteal cells of early and late stage CL. The results also did not support the idea that K8/K18 filaments influence the expression of Fas on the surface of bovine luteal cells. Potential downstream effects of these filaments on death signaling, however, remain a possibility. Importantly, the elevated expression of Fas observed on cells of early stage bovine CL compared to late stage bovine CL raises a provocative question concerning the physiological role(s) of Fas in the corpus luteum, particularly during early luteal development

Ice-melt rates during volcanic eruptions within water-drained, low pressure subglacial cavities

Subglacial volcanism generates proximal and distal hazards including large-scale flooding and increased levels of explosivity. Direct observation of subglacial volcanic processes is infeasible; therefore, we model heat transfer mechanisms during subglacial eruptions under conditions where cavities have become depressurized by connection to the atmosphere.We consider basaltic eruptions in a water-drained, low-pressure subglacial cavity, including the case when an eruption jet develops. Such drained cavities may develop on sloping terrain, where ice may be relatively shallow and where gravity drainage of meltwater will be promoted. We quantify, for the first time, the heat fluxes to the ice cavity surface that result from steam condensation during free convection at atmospheric pressure and from direct and indirect radiative heat transfer from an eruption jet. Our calculations indicate that the direct radiative heat flux from a lava fountain (a “dry” end-member eruption jet) to ice is c. 25 kW m-2 and is a minor component. The dominant heat transfer mechanism involves free convection of steam within the cavity; we estimate the resulting condensation heat flux to be c. 250 kW m-2. Absorption of radiation froma lava fountain by steamenhances convection, but the increase in condensing heat flux is modest at c. 25 kW m-2. Overall, heat fluxes to the ice cavity surface are likely to be no greater than c. 300 kW m-2. These are comparable with heat fluxes obtained by single phase convection of water in a subglacial cavity but much less than those obtained by two-phase convection

Exploring the ‘middle ground’ between state and market: the example of China

Studies of housing systems lying in the ‘middle ground’ between state and market are subject to three important shortcomings. First, the widely used Esping-Andersen (EA) approach assesses only a subset of the key housing outcomes and may be less helpful for describing changes in housing policy regimes. Second, there is too much emphasis on tenure transitions, and an assumed close correspondence between tenure labels and effective system functioning may not be valid. Third, due attention has not been given to the spatial dimensions in which housing systems operate, in particular when housing policies have a significant devolved or localised emphasis. Updating EA’s framework, we suggest a preliminary list of housing system indicators in order to capture the nature of the housing systems being developed and devolved. We verified the applicability of this indicator system with the case of China. This illustrates clearly the need for a more nuanced and systematic basis for categorising differences and changes in welfare and housing policies

Windows into Non-Euclidean Spaces

Two microlens arrays that are separated by the sum of their focal lengths form arrays of micro-telescopes. Parallel light rays that pass through corresponding lenses remain parallel, but the direction of the transmitted light rays is different. This remains true if corresponding lenses do not share an optical axis (i.e. if the two microlens arrays are shifted with respect to each other). The arrays described above are examples of generalized confocal lenslet arrays, and the light-ray-direction change in these devices is well understood [Oxburgh et al., Opt. Commun. 313, 119 (2014)]. Here we show that such micro-telescope arrays change light-ray direction like the interface between spaces with different metrics. To physicists, the concept of metrics is perhaps most familiar from General Relativity (where it is applied to spacetime, not only space, like it is here) and Transformation Optics [Pendry et al., Science 312, 1780 (2006)], where different materials are treated like spaces with different optical metrics. We illustrate the similarities between micro-telescope arrays and metric interfaces with raytracing simulations. Our results suggest the possibility of realising transformation-optics devices with micro-telescope arrays, which we investigate elsewhere

Characteristics of age-friendly bus information

Bus information is an important element to consider when developing and implementing age-friendly bus systems. Little is known regarding the bus information needs and preferences of older people. This study aims to illuminate characteristics of age-friendly bus information. Participant observations with stimulated recall interviews (n=40) were used to identify older peoples' (age 60 and over) perspectives on bus information. The data were analyzed using qualitative content analysis. A printed information location checklist also was conducted. Categorical analysis identified that older people used a variety of information sources including printed information, telephone, Internet, bus drivers, word of mouth, and experience. Positive and negative characteristics of each source were identified. Older people also required a range of levels of information complexity. Popular locations for sourcing printed information included post offices, news agents, tourist information centers, and libraries. Transport providers and policy makers should consider the needs and preferences of older people when providing bus information. Effective information provision requires a range of media, covering a broad spectrum of information complexity and through a variety of locations

Time-bin to Polarization Conversion of Ultrafast Photonic Qubits

The encoding of quantum information in photonic time-bin qubits is apt for long distance quantum communication schemes. In practice, due to technical constraints such as detector response time, or the speed with which co-polarized time-bins can be switched, other encodings, e.g. polarization, are often preferred for operations like state detection. Here, we present the conversion of qubits between polarization and time-bin encodings using a method that is based on an ultrafast optical Kerr shutter and attain efficiencies of 97% and an average fidelity of 0.827+/-0.003 with shutter speeds near 1 ps. Our demonstration delineates an essential requirement for the development of hybrid and high-rate optical quantum networks

An Assessment of the Needs of Georgian Secondary Agricultural Educators

This purpose of this study was to determine the perception of secondary educators involved in Future Farmers of Georgia (FFG) schools throughout the country of Georgia concerning their needs for furthering the existing framework of agricultural education. The researchers used a modified focus group method to meet the aformentioned purpose of this study. The population for this study consisted of the high school agricultural education teachers and their administrators who were participating in the FFG Program (n=14). Qualitative data collected from the probe (first round) was used to generate a series of 46 statements. In the second round participants were asked to rank the 46 statements using a five point Likert-type scale. Due to events in the Former Republic of Georgia, the third round could not be conducted. Therefore, the researchers concluded that the round two data would be used to meet the purpose and objectives of this study. Participants strongly agreed that the FFG program strengthens leadership skills among their students and students have become more involved in practical/labor activities. They also agreed that gaining knowledge and skills from the FFG program will improve the future development of agricultural education in the country. Participants also strongly agreed that improvement of schools’ materials, technology, and development are necessary to improve the FFG program. Participants were either neutral or agreed with the following statements: due to the FFG program, academic performance has been increased among students; and students have greater academic success in history and geography

What makes continuing education effective : perspectives of community pharmacists

Objective To explore how different aspects of the professional environment for Australian community pharmacists are perceived to be influencing the effectiveness of continuing education models in improving practice.Setting Australian community pharmacy.Methods A convenience sample of practising community pharmacists (n = 15) was recruited using the \u27snowballing\u27 technique to participate in one of four focus group teleconferences. Each focus group examined continuing education experiences from different professional perspectives and training needs (recent graduates, experienced practitioners, specialist practitioners and rural/remote practitioners).Key findings Facilitation of professional development by accreditation bodies, and new challenges resulting from the introduction of cognitive services were seen to promote a favourable environment for continuing education engagement. Complex continuing education delivery models combined with high costs and excessive workloads made it more difficult to engage with continuing education systems or try to apply knowledge to the workplace.Conclusion Results support findings from previous research that practice development requires a multifaceted approach with continuing education as just one component. Affordable and integrated models of continuing education are required in order to optimise efficacy for participants.<br /

Ice-melt rates by steam condensation during explosive subglacial eruptions

Subglacial volcanism melts cavities in the overlying ice. These cavities may be flooded with meltwater or they may be fully or partially drained. We quantify, for the first time, heat transfer rates by condensation of steam on the walls and roof of a fully or partially drained subglacial eruption cavity. Our calculations indicate that heat fluxes of up to 1 MW m−2 may be obtained when the bulk vapor in the cavity is in free convection. This is considerably smaller than heat fluxes inferred from ice penetration rates in recent subglacial eruptions. Forcing of the convection by momentum transfer from an eruption jet may allow heat fluxes of up to 2 MW m−2, consistent with values inferred for the Gjálp 1996 subglacial eruption. Vapor-dominated cavities in which vapor-liquid equilibrium is maintained have thermal dynamic responses that are an order of magnitude faster than the equivalent flooded cavities