265 research outputs found

    Proteases and caspase-like activity in the yeast Saccharomyces cerevisiae.

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    addresses: Biosciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK.types: Journal Article; Research Support, Non-U.S. Gov't; ReviewAuthor's post-print versionThe final version of record is available at http://www.biochemsoctrans.org/bst/039/bst0391502.htmΒ© The Authors Journal compilation Β© 2011 Biochemical SocietyA variety of proteases have been implicated in yeast PCD (programmed cell death) including the metacaspase Mca1 and the separase Esp1, the HtrA-like serine protease Nma111, the cathepsin-like serine carboxypeptideases and a range of vacuolar proteases. Proteasomal activity is also shown to have an important role in determining cell fate, with both pro- and anti-apoptotic roles. Caspase 3-, 6- and 8-like activities are detected upon stimulation of yeast PCD, but not all of this activity is associated with Mca1, implicating other proteases with caspase-like activity in the yeast cell death response. Global proteolytic events that accompany PCD are discussed alongside a consideration of the conservation of the death-related degradome (both at the level of substrate choice and cleavage site). The importance of both gain-of-function changes in the degradome as well as loss-of-function changes are highlighted. Better understanding of both death-related proteases and their substrates may facilitate the design of future antifungal drugs or the manipulation of industrial yeasts for commercial exploitation

    Error propagation in the rocket grenade experiment

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    Error propagation in rocket-grenade experimen

    Measurements of the structure and circulation of the stratosphere and mesosphere, 1971-2

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    Complete data from a total of 43 meteorological rocket soundings of the stratosphere and mesosphere conducted from Barrow, Alaska; Churchill, Canada; Wallops Island Va.; and Kourou, French Guiana are presented. These data consist of temperature, pressure, density, and wind profiles from 35 acoustic grenade soundings that cover the 30 to 90 km altitude range, and temperature, pressure, and density profiles from 8 pitot probe soundings that cover the 25 to 120 km altitude range. Errors for each of the 35 acoustic grenade soundings are also included

    Discovery of new 19.9-GHz methanol masers in star-forming regions

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    We have used the NASA Tidbinbilla 70-m antenna to search for emission from the 21-30 E (19.9-GHz) transition of methanol. The search was targeted towards 22 star formation regions that exhibit maser emission in the 107.0-GHz 31-40 A+ methanol transition, and in the 6.6-GHz 51-60 A+ transition characteristic of class II methanol maser sources. A total of seven sources were detected in the 21-30 E transition, six of these being new detections. Many of the new detections are weak (≳0.5 Jy), however, they appear to be weak masers rather than thermal or quasi-thermal emission. We find a strong correlation between sources that exhibit 19.9-GHz methanol masers and those that both have the class II methanol masers projected against radio continuum emission and have associated 6035-MHz OH masers. This suggests that the 19.9-GHz methanol masers arise in very specific physical conditions, probably associated with a particular evolutionary phase. In the model of Cragg, Sobolev & Godfrey these observations are consistent with gas temperatures of 50 K, dust temperatures of 150-200 K and gas densities of 106.5-107.5 cm-3

    β€˜Our Breadcrumb Trail through the Woods’: Reflections on the Use of a Secret Facebook Group as a Strategy for Surviving and Thriving on the Doctoral Journey

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    This article explores the value of attending to the emotional side of the doctoral journey by focusing on the use of a β€˜secret’ Facebook group amongst a cohort of EdD (Professional Doctorate in Education) students at one English university. Presented as a piece of action research in which the participants created an intervention to address a perceived problem and then reflected on its effectiveness, it is co-authored by the cohort of six students and their tutor. The stresses and loneliness of the doctoral journey have been well documented and constitute the β€˜problem’ addressed by this cohort of students. Their inception and use of a Facebook group was a response to challenges experienced in their studies, with the expectation of facilitating peer support. As will be shown this aim was successfully met with enhancements in academic, social, and emotional support. However, unexpected benefits arose from the interactions within the group including a normalization of the challenges of the doctoral quest and the advantage of being able to follow the β€˜breadcrumb trail’ found in the group postings as group journal and aid to reflection. Further, both tutors and students have noted the development of a strong sense of β€˜cohortness’ and inclination to work collaboratively. Through a process of individual and group reflection on experiences of the intervention, combined with analysis of the content of the postings, this article examines the characteristics of the Facebook intervention and considers some ethical implications. We suggest that key characteristics that have contributed to its success include the student ownership, the protection of the secret format, and the combination of emotionally supportive, academic, and irreverent exchanges between group members. It is hoped that these insights may be useful to future doctoral candidates and their tutors as they negotiate their own way through the doctoral woods

    Gridmapping the northern plains of Mars: Geomorphological, Radar and Water-Equivalent Hydrogen results from Arcadia Plantia

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    A project of mapping ice-related landforms was undertaken to understand the role of sub-surface ice in the northern plains. This work is the first continuous regional mapping from CTX (β€œConTeXt Camera”, 6 m/pixel; Malin et al., 2007) imagery in Arcadia Planitia along a strip 300 km across stretching from 30Β°N to 80Β°N centred on the 170Β° West line of longitude. The distribution and morphotypes of these landforms were used to understand the permafrost cryolithology. The mantled and textured signatures occur almost ubiquitously between 35Β° N and 78Β° N and have a positive spatial correlation with inferred ice stability based on thermal modelling, neutron spectroscopy and radar data. The degradational features into the LDM (Latitude Dependent Mantle) include pits, scallops and 100 m polygons and provide supporting evidence for sub-surface ice and volatile loss between 35-70Β° N in Arcadia with the mantle between 70-78Β° N appearing much more intact. Pitted terrain appears to be much more pervasive in Arcadia than in Acidalia and Utopia suggesting that the Arcadia study area had more wide-spread near-surface sub-surface ice, and thus was more susceptible to pitting, or that the ice was less well-buried by sediments. Correlations with ice stability models suggest that lack of pits north of 65-70Β° N could indicate a relatively young age (~1Ma), however this could also be explained through regional variations in degradation rates. The deposition of the LDM is consistent with an airfall hypothesis however there appears to be substantial evidence for fluvial processes in southern Arcadia with older, underlying processes being equally dominant with the LDM and degradation thereof in shaping the landscape

    Outcomes of Cardiac Screening in Adolescent Soccer Players.

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    BACKGROUND: Reports on the incidence and causes of sudden cardiac death among young athletes have relied largely on estimated rates of participation and varied methods of reporting. We sought to investigate the incidence and causes of sudden cardiac death among adolescent soccer players in the United Kingdom. METHODS: From 1996 through 2016, we screened 11,168 adolescent athletes with a mean (Β±SD) age of 16.4Β±1.2 years (95% of whom were male) in the English Football Association (FA) cardiac screening program, which consisted of a health questionnaire, physical examination, electrocardiography, and echocardiography. The FA registry was interrogated to identify sudden cardiac deaths, which were confirmed with autopsy reports. RESULTS: During screening, 42 athletes (0.38%) were found to have cardiac disorders that are associated with sudden cardiac death. A further 225 athletes (2%) with congenital or valvular abnormalities were identified. After screening, there were 23 deaths from any cause, of which 8 (35%) were sudden deaths attributed to cardiac disease. Cardiomyopathy accounted for 7 of 8 sudden cardiac deaths (88%). Six athletes (75%) with sudden cardiac death had had normal cardiac screening results. The mean time between screening and sudden cardiac death was 6.8 years. On the basis of a total of 118,351 person-years, the incidence of sudden cardiac death among previously screened adolescent soccer players was 1 per 14,794 person-years (6.8 per 100,000 athletes). CONCLUSIONS: Diseases that are associated with sudden cardiac death were identified in 0.38% of adolescent soccer players in a cohort that underwent cardiovascular screening. The incidence of sudden cardiac death was 1 per 14,794 person-years, or 6.8 per 100,000 athletes; most of these deaths were due to cardiomyopathies that had not been detected on screening. (Funded by the English Football Association and others.)

    Device Optimization of Tris-Aluminum (Alq3) Based Bilayer Organic Light Emitting Diode Structures

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    In this work we present detailed analysis of the emitted radiation spectrum from tris(8-hydroxyquinoline) aluminum (Alq3) based bilayer OLEDs as a function of: the choice of cathode, the thickness of organic layers, and the position of the hole transport layer/Alq3 interface. The calculations fully take into account dispersion in the glass substrate, the indium tin oxide anode, and in the organic layers, as well as the dispersion in the metal cathode. Influence of the incoherent transparent substrate (1 mm glass substrate) is also fully accounted for. Four cathode structures have been considered: Mg/Ag, Ca/Ag, LiF/Al, and Ag. For the hole transport layer, N,N'-diphenyl-N,N'-(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine (TPD) and N,N'-di(naphthalene-1-yl)-N,N'-diphenylbenzidine (NPB) were considered. As expected, emitted radiation is strongly dependent on the position of the emissive layer inside the cavity and its distance from the metal cathode. Although our optical model for an OLED does not explicitly include exciton quenching in vicinity of the metal cathode, designs placing the emissive layer near the cathode are excluded to avoid unrealistic results. Guidelines for designing devices with optimum emission efficiency are presented. Finally, several different devices were fabricated and characterized and experimental and calculated emission spectra were compared

    Small but crucial : the novel small heat shock protein Hsp21 mediates stress adaptation and virulence in Candida albicans

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