1,055 research outputs found
The pursuit of happiness: the social and scientific origins of Hans Selye’s natural philosophy of life
© The Author(s) 2012. Open access article.In 1956, Hans Selye tentatively suggested that the scientific study of stress could ‘help us
to formulate a precise program of conduct’ and ‘teach us the wisdom to live a rich and
meaningful life’. Nearly two decades later, Selye expanded this limited vision of social
order into a full-blown philosophy of life. In Stress without Distress, first published in 1974,
he proposed an ethical code of conduct designed to mitigate personal and social
problems. Basing his arguments on contemporary understandings of the biological
processes involved in stress reactions, Selye referred to this code as ‘altruistic egotism’.
This article explores the origins and evolution of Selye’s ‘natural philosophy of life’,
analysing the links between his theories and adjacent intellectual developments in
biology, psychosomatic and psychosocial medicine, cybernetics and socio-biology, and
situating his work in the broader cultural framework of modern western societies.Wellcome Trus
Awards, Archives, and Affects: Tropes in the World Press Photo Contest 2009 - 2011
__Abstract__
Photography contests have assumed an increasingly significant public role in the context of the global surge of mass-mediated war reporting. This study focuses on the recurrence of visual tropes in press photographs awarded in the annual contest World Press Photo (WPP) in the years 2009–11. By tropes, we mean conventions (e.g. a mourning woman, a civilian facing soldiers, a distressed witness to an atrocity) that remain unchanged despite their travels across the visual sphere, gaining professional and public recognition and having a strong affective impact. We contend that photography contests such as the WPP influence and organize a process of generic understanding of war, disaster and atrocity that is based on a number of persistent tropes, such as the mourner, the protester or the survivor amidst chaos and ruins. We further show that these tropes are gendered along traditional conceptions of femininity and masculinity, appealing strongly to both judges and wider audiences. The evidence for our claim comes from an analysis of the photographs that won awards, observation of the judging sessions, semi-structured interviews with three jury chairmen, and public commentary on the juries’ choices (blogs, newspapers and websites)
Acceptance of co-operatve education practice by the Academic Staff at Technikon South Africa
Technikons advocate the practice of co-operative education, which is an educational strategy that integrates learning through productive work with the theoretical curriculum. However, only 35% of theTechnikon SA programmes have a compulsory experiential learning component. Grounded theory research was undertaken to determine some of the basic assumptions of Technikon SA’s academic staff in this regard. Rather than starting out with a specific research problem, grounded theory explores an area of interest and allows what is relevant to emerge. Semi-structured interviews with four open-ended questions, were conducted with a stratified-random sample of 25 teaching staff at Technikon SA. It was found that, although there is some willing compliance and belief in co-operative education, it is not indicative of the organisational culture of Technikon SA.
Opsomming Technikons propageer die beoefening van ko˛peratiewe onderwys,’n opvoedkundige strategiewat leer deur produktiewewerkservaring integreermet die teoretiese kurrikulum. ByTechnikon SAegter, het slegs sowat 35% van die formele programme ’n verpligte leerervarings komponent.Teoretiese-begrondings navorsingsmetodologie is gebruik omsekere basiese veronderstellings van akademiese personeel te bepaal. Eerder as om’n spesifieke navorsingsprobleemas vertrekpunt te gebruik, ondersoek teoretiese-begronding’n areavan belang en laat die metodiek die relevante sake toe omte voorskyn te kom. Semi-gestruktureerde onderhoude,met vier ope vrae, is gevoer met ’n gestratifiseerde eweskansige steekproef van 25 akademiese personeellede vanTechnikon SA. Daar is bevind dat alhoewel daar beperkte oortuiging en gewillige uitlewing van kooperatiewe onderwys is, is dit nie beduidend as kenmerkend van die organisasie kultuur vanTechnikon SA nie
A proteomic approach to investigating gene cluster expression and secondary metabolite functionality in Aspergillus fumigatus.
A combined proteomics and metabolomics approach was utilised to advance the identification and characterisation of secondary metabolites in Aspergillus fumigatus. Here, implementation of a shotgun proteomic strategy led to the identification of non-redundant mycelial proteins (n = 414) from A. fumigatus including proteins typically under-represented in 2-D proteome maps: proteins with multiple transmembrane regions, hydrophobic proteins and proteins with extremes of molecular mass and pI. Indirect identification of secondary metabolite cluster expression was also achieved, with proteins (n = 18) from LaeA-regulated clusters detected, including GliT encoded within the gliotoxin biosynthetic cluster. Biochemical analysis then revealed that gliotoxin significantly attenuates H2O2-induced oxidative stress in A. fumigatus (p>0.0001), confirming observations from proteomics data. A complementary 2-D/LC-MS/MS approach further elucidated significantly increased abundance (p<0.05) of proliferating cell nuclear antigen (PCNA), NADH-quinone oxidoreductase and the gliotoxin oxidoreductase GliT, along with significantly attenuated abundance (p<0.05) of a heat shock protein, an oxidative stress protein and an autolysis-associated chitinase, when gliotoxin and H2O2 were present, compared to H2O2 alone. Moreover, gliotoxin exposure significantly reduced the abundance of selected proteins (p<0.05) involved in de novo purine biosynthesis. Significantly elevated abundance (p<0.05) of a key enzyme, xanthine-guanine phosphoribosyl transferase Xpt1, utilised in purine salvage, was observed in the presence of H2O2 and gliotoxin. This work provides new insights into the A. fumigatus proteome and experimental strategies, plus mechanistic data pertaining to gliotoxin functionality in the organism
Ergothioneine Biosynthesis and Functionality in the Opportunistic Fungal Pathogen, Aspergillus fumigatus.
Ergothioneine (EGT; 2-mercaptohistidine trimethylbetaine) is a trimethylated and sulphurised histidine derivative which exhibits antioxidant properties. Here we report that deletion of Aspergillus fumigatus egtA (AFUA_2G15650), which encodes a trimodular enzyme, abrogated EGT biosynthesis in this opportunistic pathogen. EGT biosynthetic deficiency in A. fumigatus significantly reduced resistance to elevated H2O2 and menadione, respectively, impaired gliotoxin production and resulted in attenuated conidiation. Quantitative proteomic analysis revealed substantial proteomic remodelling in ΔegtA compared to wild-type under both basal and ROS conditions, whereby the abundance of 290 proteins was altered. Specifically, the reciprocal differential abundance of cystathionine γ-synthase and β-lyase, respectively, influenced cystathionine availability to effect EGT biosynthesis. A combined deficiency in EGT biosynthesis and the oxidative stress response regulator Yap1, which led to extreme oxidative stress susceptibility, decreased resistance to heavy metals and production of the extracellular siderophore triacetylfusarinine C and increased accumulation of the intracellular siderophore ferricrocin. EGT dissipated H2O2 in vitro, and elevated intracellular GSH levels accompanied abrogation of EGT biosynthesis. EGT deficiency only decreased resistance to high H2O2 levels which suggests functionality as an auxiliary antioxidant, required for growth at elevated oxidative stress conditions. Combined, these data reveal new interactions between cellular redox homeostasis, secondary metabolism and metal ion homeostasis
Internal representations of smell in the Drosophila brain
Recent advances in sensory neuroscience using Drosophila olfaction as a model system have revealed brain maps representing the external world. Once we understand how the brain's built-in capability generates the internal olfactory maps, we can then elaborate how the brain computes and makes decision to elicit complex behaviors. Here, we review current progress in mapping Drosophila olfactory circuits and discuss their relationships with innate olfactory behaviors
Natural and synthetic plagioclases: Surface charge characterization and sorption of trivalent lanthanides (Eu) and actinides (Am, Cm)
he environmental fate of radiotoxic actinides may be controlled by their interactions with feldspars. Here, the sorption of trivalent minor actinides (Am, Cm) and their rare earth analog Eu onto synthetic pure Ca-feldspar (anorthite) and natural plagioclases of different Ca contents is investigated, covering ranges of [M3+] (52 nM–10 μM), solid-liquid ratios (1–3 g/L), pH (3–9), and ionic strengths (0.01–0.1 M NaCl) under both ambient and CO2-free conditions. As a first step to understand the uptake behavior of the heavy metals, the hitherto unknown surface charge and (de-)protonation reaction of Ca-feldspars is characterized. The zeta potential shows an unusual increase and charge reversal between pH 4 and 7 , which becomes more pronounced with increasing amounts of Ca in the crystal lattice and is likely connected to adsorption and/or surface precipitation of dissolved Al3+. Streaming potential measurements yield (de)protonation constants for anorthite surface sites of log K- = −6.94 ± 0.38 and log K+ = +6.84 ± 0.38. Batch sorption data shows strong immobilization of M3+ by plagioclases at mildly acidic and basic pH. Time-resolved laser fluorescence spectroscopy using Cm indicates the formation of an inner-sphere complex and its two hydrolyzed forms. The complex reactivity of dissolved Al3+ at the plagioclase-water interface severely complicated the development of a surface complexation model, emphasizing the need for additional research in this area. Our study highlights the importance of molecular-level studies to understand surface reactions and uncover unknown processes, which may have significant impact on the transport of (radiotoxic) contaminants in the geosphere
A 9-Month Hubble Space Telescope Near-UV Survey of M87. I. Light and Color Curves of 94 Novae, and a Re-determination of the Nova Rate
M87 has been monitored with a cadence of 5 days over a 9 month-long span
through the near-ultraviolet (NUV:F275W) and optical (F606W) filters of the
Wide Field Camera 3 (WFC3) of the . This
unprecedented dataset yields the NUV and optical light and color curves of 94
M87 novae, characterizing the outburst and decline properties of the largest
extragalactic nova dataset in the literature (after M31 and M81). We test and
confirm nova modelers' prediction that recurrent novae cannot erupt more
frequently that once every 45 days; show that there are zero rapidly recurring
novae in the central 1/3 of M87 with recurrence times 130 days;
demonstrate that novae closely follow the K-band light of M87 to within a few
arcsec of the galaxy nucleus; show that nova NUV light curves are as
heterogeneous as their optical counterparts, and usually peak 5 to 30 days
after visible light maximum; determine our observations' annual detection
completeness to be 71 - 77\%; and measure the rate Rnova of nova eruptions in
M87 as /yr. The corresponding luminosity-specific classical
nova rate for this galaxy is .
These rates confirm that ground-based observations of extragalactic novae miss
most faint, fast novae and those near the centers of galaxies. An annual M87
nova rate of 300 or more seems inescapable. A luminosity-specific nova rate of
in types of galaxies is
indicated by the data available in 2023.Comment: Accepted/In Press in ApJS; 3 Tables, 108 Figures, 180 page
Clinical evaluation of atypical glandular cells of undetermined significance upon cervical cytologic examination in Israeli Jewish women
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