Science-based conservation and management in wetland archaeology: the example of Sutton Common, UK

Reproduced with permission of the publisher. © Oxbow Books and the individual auhtors, 2001. Details of the publication are available at: http://www.oxbowbooks.com/bookinfo.cfm/ID/3080

Event driven executive

Tasks may be planned for execution on a single processor or are split up by the designer for execution among a plurality of signal processors. The tasks are modeled using a design aid called a precedence graph, from which a dependency table and a prerequisite table are established for reference within each processor. During execution, at the completion of a given task, an end of task interrupt is provided from any processor which has completed a task to any and all other processors including itself in which completion of that task is a prerequisite for commencement of any dependent tasks. The relevant updated data may be transferred by the processor either before or after signalling task completion to the processors needing the updated data prior to commencing execution of the dependent tasks. Coherency may be ensured, however, by sending the data before the interrupt. When the end of task interrupt is received in a processor, its dependency table is consulted to determine those tasks dependent upon completion of the task which has just been signalled as completed, and task dependency signals indicative thereof are provided and stored in a current status list of a prerequisite table. The current status of all current prerequisites are compared to the complete prerequisites listed for all affected tasks and those tasks for which the comparison indicates that all prerequisites have been met are queued for execution in a selected order

The Genetic Basis of Individual-Recognition Signals in the Mouse

SummaryThe major histocompatibility complex (MHC) is widely assumed to be a primary determinant of individual-recognition scents in many vertebrates [1–6], but there has been no functional test of this in animals with normal levels of genetic variation. Mice have evolved another polygenic and highly polymorphic set of proteins for scent communication, the major urinary proteins (MUPs) [7–12], which may provide a more reliable identity signature ([13, 14] and A.L. Sherborne, M.D.T., S. Paterson, F.J., W.E.R.O., P. Stockley, R.J.B., and J.L.H., unpublished data). We used female preference for males that countermark competitor male scents [15–17] to test the ability of wild-derived mice to recognize individual males differing in MHC or MUP type on a variable genetic background. Differences in MHC type were not used for individual recognition. Instead, recognition depended on a difference in MUP type, regardless of other genetic differences between individuals. Recognition also required scent contact, consistent with detection of involatile components through the vomeronasal system [6, 18]. Other differences in individual scent stimulated investigation but did not result in individual recognition. Contrary to untested assumptions of a vertebrate-wide mechanism based largely on MHC variation, mice use a species-specific [12] individual identity signature that can be recognized reliably despite the complex internal and external factors that influence scents [2]. Specific signals for genetic identity recognition in other species now need to be investigated

Is Cholesterol Sulfate Deficiency a Common Factor in Preeclampsia, Autism, and Pernicious Anemia?

In a recent paper, we proposed that a contributing factor in autism is a deficiency in cholesterol sulfate supply. In this paper, we investigate a link between preeclampsia and subsequent autism in the child, and we hypothesize that both conditions can be attributed to a severe depletion of cholesterol sulfate. Through studies on the Vaccine Adverse Event Reporting System (VAERS) database, we demonstrate a strong statistical relationship among the signs and symptoms associated with autism and those associated with preeclampsia, pernicious anemia, and serious adverse reactions to vaccines. We show that VAERS reports associated with symptoms typical of pernicious anemia produce both a set of symptoms that are highly correlated with preeclampsia and another set highly correlated with autism. We explain this observation via an argument that, in a severe reaction, the cascade of events subsequent to vaccination reflects a profuse production of nitric oxide (NO) and consequential destruction of both red blood cells (RBCs) and cobalamin. This may explain the diverse signs and symptoms associated with both preeclampsia and severe vaccine adverse reactions. We argue that excess NO synthesis, induced by the aluminum and antigen in vaccines, results in hemolysis of RBCs, which allows hemoglobin to scavenge the excess NO, converting it to nitrate. The NO is also scavenged by cobalamin, leading to its inactivation and contributing to subsequent pernicious anemia. Finally, we demonstrate that severe adverse reactions to vaccines can be associated with life-threatening conditions related to the heart and brain, as well as stillbirth, when the vaccine is administered to a woman in the third-trimester of pregnancy, as demonstrated by statistical analysis of the Gardasil records

Targeted DamID reveals differential binding of mammalian pluripotency factors.

The precise control of gene expression by transcription factor networks is crucial to organismal development. The predominant approach for mapping transcription factor-chromatin interactions has been chromatin immunoprecipitation (ChIP). However, ChIP requires a large number of homogeneous cells and antisera with high specificity. A second approach, DamID, has the drawback that high levels of Dam methylase are toxic. Here, we modify our targeted DamID approach (TaDa) to enable cell type-specific expression in mammalian systems, generating an inducible system (mammalian TaDa or MaTaDa) to identify genome-wide protein/DNA interactions in 100 to 1000 times fewer cells than ChIP-based approaches. We mapped the binding sites of two key pluripotency factors, OCT4 and PRDM14, in mouse embryonic stem cells, epiblast-like cells and primordial germ cell-like cells (PGCLCs). PGCLCs are an important system for elucidating primordial germ cell development in mice. We monitored PRDM14 binding during the specification of PGCLCs, identifying direct targets of PRDM14 that are key to understanding its crucial role in PGCLC development. We show that MaTaDa is a sensitive and accurate method for assessing cell type-specific transcription factor binding in limited numbers of cells

Is ongoing testosterone required after pubertal induction in Duchenne muscular dystrophy?

Glucocorticoids (GCs) reduce inflammation and preserve muscle function in boys with Duchenne muscular dystrophy (DMD) but cause pubertal delay. Pubertal induction with testosterone is recommended but longer-term outcome is unknown. Objective: To assess hypothalamic–pituitary–gonadal axis, muscle volume and function 5 years after pubertal induction. Methods: A prospective observational follow-up of a clinical study was conducted. 15 GC-treated males with DMD were treated with incremental testosterone for 2 years (end of regimen +2 years) then evaluated at +2.5 years and +5 y ears (final follow-up ~3 years after last injection). Data collected included testicular volume (TV), gonadotrophin, testosterone, inhibin B, muscle function, and limb muscle MRI. Results: Participants were 18.7 years (s.d. 1.6) at the final follow-up and had been on GC for 11.2 years (s.d. 2.2). Testosterone levels were similar at +2.5 years (8.6 nmol /L (s.d. 3.4) and 5 years (11.0 nmol/L (s.d. 6.1). TV increased from 2.8 mL ( s.d. 0.9) at +2 years to 7.1 mL (s.d. 1.8) then 10.6 mL (s.d. 3.5) at +2.5 years and +5.0 years (P < 0.001). Inhibin B levels increased from 55.6 pg/mL (s.d. 47.0) at baseline to 158.2 pg/mL ( s.d. 87.6), P =0.004 at 5 years but remained lower than reference values (mean 305 pg/mL). Muscle contractile bulk decreased. Interpretation: Pubertal induction with testosterone in DMD is associated with HPG axis activation and ongoing increases in inhibin B, TV, and testosterone concentrations. Some patients have normal levels which is promising regarding future fertility. Given the beneficial impact of testosterone on bone health, muscle, and well-being, monitoring testosterone levels in this population and supplementation of sub-optimal levels is important

PhillydotMap: The Shape of Philadelphia

This book is the outgrowth of a working group entitled, “Modeling Urban Environmental Impacts on Health, Development, and Behavior sponsored by the University of Pennsylvania Institute for Urban Research. The purpose of the working gropu was to engage faculty from across campus and to encourage their collaborative use of GIS technology in the modeling of urban form and function. These ten chapters represent a wide range of GIS applications, from community-based social services to public history to social science research

Resumming the large-N approximation for time evolving quantum systems

In this paper we discuss two methods of resumming the leading and next to leading order in 1/N diagrams for the quartic O(N) model. These two approaches have the property that they preserve both boundedness and positivity for expectation values of operators in our numerical simulations. These approximations can be understood either in terms of a truncation to the infinitely coupled Schwinger-Dyson hierarchy of equations, or by choosing a particular two-particle irreducible vacuum energy graph in the effective action of the Cornwall-Jackiw-Tomboulis formalism. We confine our discussion to the case of quantum mechanics where the Lagrangian is $L(x,\dot{x}) = (1/2) \sum_{i=1}^{N} \dot{x}_i^2 - (g/8N) [ \sum_{i=1}^{N} x_i^2 - r_0^2 ]^{2}$. The key to these approximations is to treat both the $x$ propagator and the $x^2$ propagator on similar footing which leads to a theory whose graphs have the same topology as QED with the $x^2$ propagator playing the role of the photon. The bare vertex approximation is obtained by replacing the exact vertex function by the bare one in the exact Schwinger-Dyson equations for the one and two point functions. The second approximation, which we call the dynamic Debye screening approximation, makes the further approximation of replacing the exact $x^2$ propagator by its value at leading order in the 1/N expansion. These two approximations are compared with exact numerical simulations for the quantum roll problem. The bare vertex approximation captures the physics at large and modest $N$ better than the dynamic Debye screening approximation.Comment: 30 pages, 12 figures. The color version of a few figures are separately liste