1,941 research outputs found
Iodine status of soils, grain crops, and irrigation waters in Pakistan
A study was carried out across 86 locations of the country to investigate iodine supply potential of soils, grains and underground waters for onward design of an environmental intervention in Pakistan. Wheat crops were the principal crop in this study since it supplies 75 % of calorific energy in an average Pakistani diet. TMAH-extractable iodine in soils provided a geometric mean of 0.66 ”g gâ1, far lower than the worldwide mean of 3.0 ”g gâ1 for soil iodine. Bioavailable (water-extractable) iodine concentration had a geometric mean of 2.4 % (of TMAH-extractable iodine). Median iodine concentrations in tube well sourced waters were 7.3 ”g Lâ1. Median wheat grain-iodine concentrations were 0.01 ”g gâ1. In most of the grain samples, TMAH-extractable iodine was below detection limit of 0.01 ”g gâ1. The highest wheat grain iodine was measured on a soil having highest TMAH-extractable iodine. An iodine intake of 25.4 ”g a day has been estimated based on median wheat grain iodine measured and groundwater consumption compared to world health organisation (WHO) recommendations of iodine intake of 150 ”g a day. This nominal intake of iodine is alarming since 60 % of Pakistani households do not consume iodised salt
Human dynamics revealed through Web analytics
When the World Wide Web was first conceived as a way to facilitate the
sharing of scientific information at the CERN (European Center for Nuclear
Research) few could have imagined the role it would come to play in the
following decades. Since then, the increasing ubiquity of Internet access and
the frequency with which people interact with it raise the possibility of using
the Web to better observe, understand, and monitor several aspects of human
social behavior. Web sites with large numbers of frequently returning users are
ideal for this task. If these sites belong to companies or universities, their
usage patterns can furnish information about the working habits of entire
populations. In this work, we analyze the properly anonymized logs detailing
the access history to Emory University's Web site. Emory is a medium size
university located in Atlanta, Georgia. We find interesting structure in the
activity patterns of the domain and study in a systematic way the main forces
behind the dynamics of the traffic. In particular, we show that both linear
preferential linking and priority based queuing are essential ingredients to
understand the way users navigate the Web.Comment: 7 pages, 8 figure
The S. pombe translation initiation factor eIF4G is sumoylated and associates with the SUMO protease Ulp2
SUMO is a small post-translational modifier, that is attached to lysine residues in target proteins. It acts by altering proteinprotein
interactions, protein localisation and protein activity. SUMO chains can also act as substrates for ubiquitination,
resulting in proteasome-mediated degradation of the target protein. SUMO is removed from target proteins by one of a
number of specific proteases. The processes of sumoylation and desumoylation have well documented roles in DNA
metabolism and in the maintenance of chromatin structure. To further analyse the role of this modification, we have
purified protein complexes containing the S. pombe SUMO protease, Ulp2. These complexes contain proteins required for
ribosome biogenesis, RNA stability and protein synthesis. Here we have focussed on two translation initiation factors that
we identified as co-purifying with Ulp2, eIF4G and eIF3h. We demonstrate that eIF4G, but not eIF3h, is sumoylated. This
modification is increased under conditions that produce cytoplasmic stress granules. Consistent with this we observe partial
co-localisation of eIF4G and SUMO in stressed cells. Using HeLa cells, we demonstrate that human eIF4GI is also sumoylated;
in vitro studies indicate that human eIF4GI is modified on K1368 and K1588, that are located in the C-terminal eIF4A- and
Mnk-binding sites respectively
Anxious/depressed symptoms are related to microstructural maturation of white matter in typically developing youths
AbstractThere are multiple recent reports of an association between anxious/depressed (A/D) symptomatology and the rate of cerebral cortical thickness maturation in typically developing youths. We investigated the degree to which anxious/depressed symptoms are tied to age-related microstructural changes in cerebral fiber pathways. The participants were part of the NIH MRI Study of Normal Brain Development. Child Behavior Checklist A/D scores and diffusion imaging were available for 175 youths (84 males, 91 females; 241 magnetic resonance imagings) at up to three visits. The participants ranged from 5.7 to 18.4 years of age at the time of the scan. Alignment of fractional anisotropy data was implemented using FSL/Tract-Based Spatial Statistics, and linear mixed model regression was carried out using SPSS. Child Behavior Checklist A/D was associated with the rate of microstructural development in several white matter pathways, including the bilateral anterior thalamic radiation, bilateral inferior longitudinal fasciculus, left superior longitudinal fasciculus, and right cingulum. Across these pathways, greater age-related fractional anisotropy increases were observed at lower levels of A/D. The results suggest that subclinical A/D symptoms are associated with the rate of microstructural development within several white matter pathways that have been implicated in affect regulation, as well as mood and anxiety psychopathology.</jats:p
Preferencial growth: exact solution of the time dependent distributions
We consider a preferential growth model where particles are added one by one
to the system consisting of clusters of particles. A new particle can either
form a new cluster (with probability q) or join an already existing cluster
with a probability proportional to the size thereof. We calculate exactly the
probability \Pm_i(k,t) that the size of the i-th cluster at time t is k. We
analyze the asymptotics, the scaling properties of the size distribution and of
the mean size as well as the relation of our system to recent network models.Comment: 8 pages, 4 figure
Declarative referential gesturing in a wild chimpanzee (Pan troglodytes)
Humans are argued to be unique in their ability and motivation to share attention with others about external entitiesâsharing attention for sharingâs sake. Indeed, in humans, using referential gestures declaratively to direct the attention of others toward external objects and events emerges in the first year of life. In contrast, wild great apes seldom use referential gestures, and when they do, it seems to be exclusively for imperative purposes. This apparent species difference has fueled the argument that the motivation and ability to share attention with others is a human-specific trait with important downstream consequences for the evolution of our complex cognition [M. Tomasello, Becoming Human (2019)]. Here, we report evidence of a wild ape showing a conspecific an item of interest. We provide video evidence of an adult female chimpanzee, Fiona, showing a leaf to her mother, Sutherland, in the context of leaf grooming in Kibale Forest, Uganda. We use a dataset of 84 similar leaf-grooming events to explore alternative explanations for the behavior, including food sharing and initiating dyadic grooming or playing. Our observations suggest that in highly specific social conditions, wild chimpanzees, like humans, may use referential showing gestures to direct othersâ attention to objects simply for the sake of sharing. The difference between humans and our closest living relatives in this regard may be quantitative rather than qualitative, with ramifications for our understanding of the evolution of human social cognition
Making Sense of a New Transport System: An Ethnographic Study of the Cambridgeshire Guided Busway
An increase in public transport use has the potential to contribute to improving population health, and there is growing interest in innovative public transport systems. Yet how new public transport infrastructure is experienced and integrated (or not) into daily practice is little understood. We investigated how the Cambridgeshire Guided Busway, UK, was used and experienced in the weeks following its opening, using the method of participant observation (travelling on the busway and observing and talking to passengers) and drawing on Normalization Process Theory to interpret our data. Using excerpts of field notes to support our interpretations, we describe how the ease with which the new transport system could be integrated into existing daily routines was important in determining whether individuals would continue to use it. It emerged that there were two groups of passengers with different experiences and attitudes. Passengers who had previously travelled frequently on regular bus services did not perceive the new system to be an improvement; consequently, they were frustrated that it was differentiated from and not coherent with the regular system. In contrast, passengers who had previously travelled almost exclusively by car appraised the busway positively and perceived it to be a novel and superior form of travel. Our rich qualitative account highlights the varied and creative ways in which people learn to use new public transport and integrate it into their everyday lives. This has consequences for the introduction and promotion of future transport innovations. It is important to emphasise the novelty of new public transport, but also the ways in which its use can become ordinary and routine. Addressing these issues could help to promote uptake of other public transport interventions, which may contribute to increasing physical activity and improving population health. © 2013 Jones et al
Spectral plots and the representation and interpretation of biological data
It is basic question in biology and other fields to identify the char-
acteristic properties that on one hand are shared by structures from a
particular realm, like gene regulation, protein-protein interaction or neu- ral
networks or foodwebs, and that on the other hand distinguish them from other
structures. We introduce and apply a general method, based on the spectrum of
the normalized graph Laplacian, that yields repre- sentations, the spectral
plots, that allow us to find and visualize such properties systematically. We
present such visualizations for a wide range of biological networks and compare
them with those for networks derived from theoretical schemes. The differences
that we find are quite striking and suggest that the search for universal
properties of biological networks should be complemented by an understanding of
more specific features of biological organization principles at different
scales.Comment: 15 pages, 7 figure
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