Conservation of Galápagos Marine Iguanas (Amblyrhynchus cristatus)

Galápagos Marine Iguanas are highly abundant along many of the archipelago’s shorelines. Total estimated population size varies between 37,000 and 280,000 individuals. Marine Iguanas have evolved in the absence of major predators, and their populations are regulated by cyclically recurring famine (El Niño) and feast (La Niña) events. Population declines are strongly density-dependent: the higher the population density, the higher the mortalities during El Niños (from 10–90%). Recovery after El Niños is rapid, as females compensate by reproducing younger and laying more eggs. Marine Iguana morphology differs between islands. Seven subspecies have been proposed, although only three major clades can be distinguished genetically. Twelve populations (approximately 74% of all Marine Iguanas) still live in pristine environments, whereas five populations (26% of all Marine Iguanas) suffer from anthropogenic influences. Major conservation problems arise from introduced predators (cats, dogs, rats, and pigs) and from combinations of natural events (El Niño) and anthropogenic disasters such as oil spills. The most recent oil spill in 2001 killed 62% of all Marine Iguanas on Santa Fe Island. Management requirements for the future include: (i) investigating population trends in Western Isabela and San Cristobal islands, (ii) investigating whether harbor areas are population sinks because of environmental contaminants, (iii) establishing a recovery program for oil-contaminated iguanas, especially their reinoculation with hindgut microsymbionts, and (iv) developing husbandry techniques and establishing a captive propagation program as a population backup plan (Marine Iguanas have not been bred in captivity)

Conservation of Galápagos Marine Iguanas (Amblyrhynchus cristatus)

Galápagos Marine Iguanas are highly abundant along many of the archipelago’s shorelines. Total estimated population size varies between 37,000 and 280,000 individuals. Marine Iguanas have evolved in the absence of major predators, and their populations are regulated by cyclically recurring famine (El Niño) and feast (La Niña) events. Population declines are strongly density-dependent: the higher the population density, the higher the mortalities during El Niños (from 10–90%). Recovery after El Niños is rapid, as females compensate by reproducing younger and laying more eggs. Marine Iguana morphology differs between islands. Seven subspecies have been proposed, although only three major clades can be distinguished genetically. Twelve populations (approximately 74% of all Marine Iguanas) still live in pristine environments, whereas five populations (26% of all Marine Iguanas) suffer from anthropogenic influences. Major conservation problems arise from introduced predators (cats, dogs, rats, and pigs) and from combinations of natural events (El Niño) and anthropogenic disasters such as oil spills. The most recent oil spill in 2001 killed 62% of all Marine Iguanas on Santa Fe Island. Management requirements for the future include: (i) investigating population trends in Western Isabela and San Cristobal islands, (ii) investigating whether harbor areas are population sinks because of environmental contaminants, (iii) establishing a recovery program for oil-contaminated iguanas, especially their reinoculation with hindgut microsymbionts, and (iv) developing husbandry techniques and establishing a captive propagation program as a population backup plan (Marine Iguanas have not been bred in captivity)

Identifying the Enablers and Barriers of Information Technology Personnel Transition

This paper reports the initial findings from a National Science Foundation supported study of IT personnel transition. We used the revealed causal mapping method (Narayanan and Fahey 1990) to elicit barriers, enablers, and examples of IT personnel transition. This paper reveals new knowledge and insight into factors that enable and prevent IT personnel transition as organizations evolve. The data is presented in the form of interpretation of revealed causal maps from 83 respondents. The results of this study are the first steps toward developing a theory of IT personnel transition that is distinct from general transition theories

Barns perspektiv i forskning om barns psykiska hälsa – förhållningssätt och utmaningar

I den här artikeln diskuteras barns perspektiv som utmaning och förhållningssätt i forskning om psykisk hälsa och ohälsa hos barn och unga. Utgångspunkten tas i frågan hur barns perspektiv i forskning skiljer sig från barns perspektiv såsom det definieras i politiska sammanhang. Mot bakgrund av de reflekterande kritiska synpunkter som mejslats fram av barn och barndomsforskare idag framträder en viktig skillnad. Den bygger på att forskare synliggör sina teoretiska och metodologiska utgångspunkter när resultat som omfattar barns perspektiv presenteras. Det blir en särskild utmaning när allt fler forskare från ämnen också utanför barn och barndomsforskning börjar utgå ifrån barns perspektiv. Ytterligare en utmaning knyter an till forskningsområdet barns psykiska hälsa och ohälsa. Med stöd av Ian Hackings teoretiska resonemang om ”the looping effects” (Hacking 1995, 1999) diskuteras ett sätt varpå barns perspektiv kan bidra till en breddning av forskning om psykisk hälsa och ohälsa

“A reason behind every action”. The early years of Swedish Child Psychiatry, 1930-1945

The development of Swedish child psychiatry is not a coherent, straightforward narrative of a steady progression. Child mental health was raised as a topic in the early twentieth century and in the 1920s and 30s child guidance activities began to take shape in the larger municipalities, carried out by philanthropic or public agents. In this period the neuropsychiatric oriented child psychiatrists were challenged by those with an interest in psychoanalysis in defining and treating childhood mental ill health. There was no sign of a cohesive national approach to child mental health services until the early 1940s, when the first steps in such direction were taken by the Swedish government. The political ideas underpinning these actions were based on a psychodynamic tradition combined with a political vision of social change.Le développement de la psychiatrie de l’enfant en Suède ne suit pas un parcours cohérent et linéaire. La santé mentale de l’enfant fut une thématique mise en avant au début du xxe siècle et à partir des années 1920-1930, des activités de guidance infantile s’établirent dans les principales villes soutenues par des acteurs publics ou associatifs. Au cours de cette période, les psychiatres de l’enfant d’orientation neuropsychiatrique étaient défiés par ceux qui manifestaient un intérêt pour la psychanalyse et sa capacité à définir un traitement pour l’enfance mentalement perturbée. Il n’y eut pas de politique nationale homogène inspirant les services de santé mentale jusqu’à ce que le gouvernement suédois dans les années 1940 établisse les premières mesures allant dans cette direction. Les idées inspirant cette politique étaient basées sur la tradition psychodynamique articulée à un objectif politique de transformation sociale

Raw and Count Data Comparability of Hip-Worn ActiGraph GT3X+ and Link Accelerometers

To enable inter- and intrastudy comparisons it is important to ascertain comparability among accelerometer models. Purpose: The purpose of this study was to compare raw and count data between hip-worn ActiGraph GT3X+ and GT9X Link accelerometers. Methods: Adults (n = 26 (n = 15 women); age, 49.1 T 20.0 yr) wore GT3X+ and Link accelerometers over the right hip for an 80-min protocol involving 12–21 sedentary, household, and ambulatory/exercise activities lasting 2–15 min each. For each accelerometer, mean and variance of the raw (60 Hz) data for each axis and vector magnitude (VM) were extracted in 30-s epochs. A machine learning model (Montoye 2015) was used to predict energy expenditure in METs from the raw data. Raw data were also processed into activity counts in 30-s epochs for each axis and VM, with Freedson 1998 and 2011 count-based regression models used to predictMETs. Time spent in sedentary, light, moderate, and vigorous intensities was derived from predicted METs from each model. Correlations were calculated to compare raw and count data between accelerometers, and percent agreement was used to compare epoch-by-epoch activity intensity. Results: For raw data, correlations for mean acceleration were 0.96 T 0.05, 0.89 T 0.16, 0.71 T 0.33, and 0.80 T 0.28, and those for variance were 0.98 T 0.02, 0.98 T 0.03, 0.91 T 0.06, and 1.00 T 0.00 in the X, Y, and Z axes and VM, respectively. For count data, corresponding correlations were 1.00 T 0.01, 0.98 T 0.02, 0.96 T 0.04, and 1.00 T 0.00, respectively. Freedson 1998 and 2011 count-based models had significantly higher percent agreement for activity intensity (95.1% T 5.6% and 95.5% T 4.0%) compared with theMontoye 2015 raw data model (61.5% T 27.6%; P G 0.001). Conclusions: Count data were more highly comparable than raw data between accelerometers. Data filtering and/or more robust raw data models are needed to improve raw data comparability between ActiGraph GT3X+ and Link accelerometers

Assembly and Functional Architecture of Bacterial Chemoreceptor Nanoarrays

Transmembrane chemotaxis receptors are found in bacteria in extended hexagonal arrays stabilized by the membrane and by cytosolic binding partners, the kinase CheA and coupling protein CheW. Models of array architecture and assembly propose receptors cluster into trimers-of-dimers that associate with one CheA dimer and two CheW monomers to form the minimal core unit necessary for signal transduction. Reconstructing in vitro chemoreceptor ternary complexes that are homogenous, functional, and exhibit native architecture remains a challenge. Here we report that His-tag mediated receptor dimerization with divalent metals is sufficient to drive assembly of native-like functional arrays of a receptor cytoplasmic fragment. Our results indicate receptor dimerization initiates assembly and precedes formation of ternary complexes with partial kinase activity. Restoration of maximal kinase activity coincides with a shift to larger complexes, suggesting that kinase activity depends on interactions beyond the core unit. We hypothesize that achieving maximal activity requires building core units into hexagons and/or coalescing hexagons into the extended lattice. This discovery may also address a previously observed density-dependent transition between signaling states. To further test this, we implemented a paramagnetic relaxation enhancement (PRE) based solid-state NMR approach to obtain long-range (≥ 20 Å) distance constraints across the trimer of dimers interface. Overall, the work presented here shows that minimally perturbing His-tag mediated dimerization promotes assembly of chemoreceptor arrays with native architecture, and thus enabled us to gain insights into the mode of array assembly and the role of the core functional unit

Insights into the behaviour of systems biology models from dynamic sensitivity and identifiability analysis: a case study of an NF-kB signaling pathway

Mathematical modelling offers a variety of useful techniques to help in understanding the intrinsic behaviour of complex signal transduction networks. From the system engineering point of view, the dynamics of metabolic and signal transduction models can always be described by nonlinear ordinary differential equations (ODEs) following mass balance principles. Based on the state-space formulation, many methods from the area of automatic control can conveniently be applied to the modelling, analysis and design of cell networks. In the present study, dynamic sensitivity analysis is performed on a model of the IB-NF-B signal pathway system. Univariate analysis of the Euclidean-form overall sensitivities shows that only 8 out of the 64 parameters in the model have major influence on the nuclear NF-B oscillations. The sensitivity matrix is then used to address correlation analysis, identifiability assessment and measurement set selection within the framework of least squares estimation and multivariate analysis. It is shown that certain pairs of parameters are exactly or highly correlated to each other in terms of their effects on the measured variables. The experimental design strategy provides guidance on which proteins should best be considered for measurement such that the unknown parameters can be estimated with the best statistical precision. The whole analysis scheme we describe provides efficient parameter estimation techniques for complex cell networks