Chemical characteristics of macroscopic pyrogenic carbon following millennial-scale environmental exposure

Pyrogenic Carbon (PyC) is ubiquitous in global environments, and is now known to form a significant, and dynamic component of the global carbon cycle, with at least some forms of PyC persisting in their depositional environment for many millennia. Despite this, the factors that determine the turnover of PyC remain poorly understood, as do the physical and chemical changes that this material undergoes when exposed to the environment over tens of thousands of years. Here, we present the results of an investigation to address these knowledge gaps through chemical and physical analysis of a suite of wood PyC samples exposed to the environment for varying time periods, to a maximum of >90,000 years. This includes an assessment of the quantity of resistant carbon, known as Stable Polyaromatic Carbon (SPAC) versus more chemically labile carbon in the samples. We find that, although production temperature is likely to determine the initial ‘degradation potential’ of PyC, an extended exposure to environmental conditions does not necessarily mean that remaining PyC always progresses to a ‘SPAC-dominant’ state. Instead, some ancient PyC can be composed largely of chemical components typically thought of as environmentally labile, and it is likely that the depositional environment drives the trajectory of preservation versus loss of PyC over time. This has important implications for the size of global PyC stocks, which may have been underestimated, and also for the potential loss of previously stored PyC, when its depositional environment alters through environmental or climatic changes

Preparing to work: dramaturgy, cynicism and normative ‘remote’ control in the socialization of graduate recruits in management consulting

online) This paper examines the socialization of graduate recruits into a knowledge intensive labour process and organizational culture. Theoretically the paper draws upon the idea of ‘preparing for work’ to position this early socialization as a crucial moment in the production of subjectivities suited (and booted) for the labour process of management consulting. Empirically the paper reports on a two-day induction session for new graduate recruits joining a global management consultancy and their responses to this training. Particular attention is given to the use of role-play and a dramaturgical workshop used in part of the training process. The paper argues that the utilization of dramaturgy in training is consistent with the overall approach to control developed in the firm in response to the fact that the labour process of consulting is often conducted on client sites, away from any direct supervisory gaze. As such, the consultants were subjected to a form of cultural control that was designed to function independently of direct supervision. This control did not operate directly upon the new employees professed values, however, but at one step removed so that a ‘cynical distance’ from the content of the organization’s culture was accepted so long as a professional ‘ethic of behaviour’ was established. By focusing on an ‘ethic of behaviour’ these young professionals were encouraged to internalize a self-control akin to that of an actor, rather than internalizing the corporate values entirely

Phosphorylation of toxoplasma gondii secreted proteins during acute and chronic stages of infection

ABSTRACT The intracellular parasite Toxoplasma gondii resides within a membrane-bound parasitophorous vacuole (PV) and secretes an array of proteins to establish this replicative niche. It has been shown previously that Toxoplasma secretes kinases and that numerous proteins are phosphorylated after secretion. Here, we assess the role of the phosphorylation of strand-forming protein 1 (SFP1) and the related protein GRA29, two secreted proteins with unknown function. We show that both proteins form stranded structures in the PV that are independent of the previously described intravacuolar network or actin. SFP1 and GRA29 can each form these structures independently of other Toxoplasma secreted proteins, although GRA29 appears to regulate SFP1 strands. We show that an unstructured region at the C termini of SFP1 and GRA29 is required for the formation of strands and that mimicking the phosphorylation of this domain of SFP1 negatively regulates strand development. When tachyzoites convert to chronic-stage bradyzoites, both proteins show a dispersed localization throughout the cyst matrix. Many secreted proteins are reported to dynamically redistribute as the cyst forms, and secreted kinases are known to play a role in cyst formation. Using quantitative phosphoproteome and proteome analyses comparing tachyzoite and early bradyzoite stages, we reveal widespread differential phosphorylation of secreted proteins. While we found no direct evidence for phosphorylation playing a dominant role for SFP1/GRA29 redistribution in the cyst, these data support a model in which secreted kinases and phosphatases contribute to the regulation of secreted proteins during stage conversion. IMPORTANCE Toxoplasma gondii is a common parasite that infects up to one-third of the human population. Initially, the parasite grows rapidly, infecting and destroying cells of the host, but subsequently switches to a slow-growing form and establishes chronic infection. In both stages, the parasite lives within a membrane-bound vacuole within the host cell, but in the chronic stage, a durable cyst wall is synthesized, which provides protection to the parasite during transmission to a new host. Toxoplasma secretes proteins into the vacuole to build its replicative niche, and previous studies identified many of these proteins as phosphorylated. We investigate two secreted proteins and show that a phosphorylated region plays an important role in their regulation in acute stages. We also observed widespread phosphorylation of secreted proteins when parasites convert from acute to chronic stages, providing new insight into how the cyst wall may be dynamically regulated

Three Dimensional Visualization and Fractal Analysis of Mosaic Patches in Rat Chimeras: Cell Assortment in Liver, Adrenal Cortex and Cornea

The production of organ parenchyma in a rapid and reproducible manner is critical to normal development. In chimeras produced by the combination of genetically distinguishable tissues, mosaic patterns of cells derived from the combined genotypes can be visualized. These patterns comprise patches of contiguously similar genotypes and are different in different organs but similar in a given organ from individual to individual. Thus, the processes that produce the patterns are regulated and conserved. We have previously established that mosaic patches in multiple tissues are fractal, consistent with an iterative, recursive growth model with simple stereotypical division rules. Fractal dimensions of various tissues are consistent with algorithmic models in which changing a single variable (e.g. daughter cell placement after division) switches the mosaic pattern from islands to stripes of cells. Here we show that the spiral pattern previously observed in mouse cornea can also be visualized in rat chimeras. While it is generally held that the pattern is induced by stem cell division dynamics, there is an unexplained discrepancy in the speed of cellular migration and the emergence of the pattern. We demonstrate in chimeric rat corneas both island and striped patterns exist depending on the age of the animal. The patches that comprise the pattern are fractal, and the fractal dimension changes with the age of the animal and indicates the constraint in patch complexity as the spiral pattern emerges. The spiral patterns are consistent with a loxodrome. Such data are likely to be relevant to growth and cell division in organ systems and will help in understanding how organ parenchyma are generated and maintained from multipotent stem cell populations located in specific topographical locations within the organ. Ultimately, understanding algorithmic growth is likely to be essential in achieving organ regeneration in vivo or in vitro from stem cell populations

Walking the walk: a phenomenological study of long distance walking

Evidence suggests that regular walking can elicit significant psychological benefits although little evidence exists concerning long distance walking. The purpose of this study was to provide detailed accounts of the experiences of long distance walkers. Phenomenological interviews were conducted with six long distance walkers. Data were transcribed verbatim before researchers independently analyzed the transcripts. Participants reported a cumulative effect with positive feelings increasing throughout the duration of the walk. Long distance walking elicited positive emotions, reduced the effects of life-stress, and promoted an increased sense of well-being and personal growth. Results are aligned to theories and concepts from positive psychology

Enabling the classroom and the curriculum: higher education, literary studies and disability

In this article the tripartite model of disability is applied to the lived experience of twenty-first-century higher education. The tripartite model facilitates a complex understanding of disability that recognises assumptions and discrimination but not at the cost of valued identity. This being so, not only the normative positivisms and non-normative negativisms but also the non-normative positivisms of the classroom and the curriculum are explored. Inclusion is taken as the starting point and the argument progresses to a profound and innovational appreciation of disability. The problem addressed is that inclusion, as shown in The Biopolitics of Disability, constitutes little more than inclusion-ism until disability is recognised in the context of alternative lives and values that neither enforce nor reify normalcy. Informed by this understanding, the article adopts the disciplinary example of literary studies and refers to Brian Friel’s Molly Sweeney as a primary text. The conclusion is that, despite passive and active resistance, disability enters higher education in many ways, most of which are beneficial to students and educators alike

High sensitivity cardiac troponin and the under-diagnosis of myocardial infarction in women: prospective cohort study

Objective To evaluate the diagnosis of myocardial infarction using a high sensitivity troponin I assay and sex specific diagnostic thresholds in men and women with suspected acute coronary syndrome. Design Prospective cohort study. Setting Regional cardiac centre, United Kingdom. Participants Consecutive patients with suspected acute coronary syndrome (n=1126, 46% women). Two cardiologists independently adjudicated the diagnosis of myocardial infarction by using a high sensitivity troponin I assay with sex specific diagnostic thresholds (men 34 ng/L, women 16 ng/L) and compared with current practice where a contemporary assay (50 ng/L, single threshold) was used to guide care. Main outcome measure Diagnosis of myocardial infarction. Results The high sensitivity troponin I assay noticeably increased the diagnosis of myocardial infarction in women (from 11% to 22%; P<0.001) but had a minimal effect in men (from 19% to 21%, P=0.002). Women were less likely than men to be referred to a cardiologist or undergo coronary revascularisation (P<0.05 for both). At 12 months, women with undisclosed increases in troponin concentration (17-49 ng/L) and those with myocardial infarction (≥50 ng/L) had the highest rate of death or reinfarction compared with women without (≤16 ng/L) myocardial infarction (25%, 24%, and 4%, respectively; P<0.001). Conclusions Although having little effect in men, a high sensitivity troponin assay with sex specific diagnostic thresholds may double the diagnosis of myocardial infarction in women and identify those at high risk of reinfarction and death. Whether use of sex specific diagnostic thresholds will improve outcomes and tackle inequalities in the treatment of women with suspected acute coronary syndrome requires urgent attention