Arsenic in Rice Grown in Low-Arsenic Environments in Bangladesh

It has previously been reported that rice grown in regions of Bangladesh with low-arsenic (As) concentrations in irrigation water can have relatively high concentrations of As within their grains. This study aims to determine how widespread this issue is, and determine the seasonal variation in grain As in these regions. Levels of As were measured in shallow tube well (STW) water, soils, and rice grains collected during the Boro (dry) and Aman (wet) seasons from six Upazilas (sub-districts) of Bangladesh where As levels in groundwater were known to be low. In all the Upazilas, the As concentrations in STW water were <50 mu g L-1. The As levels in soil samples collected from the Upazilas ranged between 0.2-4.0 mgkg(-1) in the sam-ples collected during the Boro season, and 0.4-5.7 mg kg(-1) in the samples collected in the Aman season. Levels of As in both Boro and Aman rice grain varied widely: in Boro 0.02-0.45 mg kg(-1), and in Aman 0.01-0.29 mg kg(-1). Additionally, a household survey of dietary habits was also conducted in one Upazila by estimating As ingestion by 15 head female members. On average, the women consumed 3.1 L of water, 1.1 kg of cooked rice, and 42 g dry weight of curry per day. The total As ingestion rates ranged from 31.1-129.3 mu g day(-1) (mean 63.5 mu g kg(-1)). These findings indicate that the major route of As ingestion in low groundwater As areas of Bangladesh is rice, followed by curry and then water.

Genome-wide DNA profiling of marginal zone lymphomas identifies subtype-specific lesions with an impact on the clinical outcome

Marginal zone B-cell lymphomas (MZLs) have been divided into 3 distinct subtypes (extranodal MZLs of mucosa-associated lymphoid tissue [MALT] type, nodal MZLs, and splenic MZLs). Nevertheless, the relationship between the subtypes is still unclear. We performed a comprehensive analysis of genomic DNA copy number changes in a very large series of MZL cases with the aim of addressing this question. Samples from 218 MZL patients (25 nodal, 57 MALT, 134 splenic, and 2 not better specified MZLs) were analyzed with the Affymetrix Human Mapping 250K SNP arrays, and the data combined with matched gene expression in 33 of 218 cases. MALT lymphoma presented significantly more frequently gains at 3p, 6p, 18p, and del(6q23) (TNFAIP3/A20), whereas splenic MZLs was associated with del(7q31), del(8p). Nodal MZLs did not show statistically significant differences compared with MALT lymphoma while lacking the splenic MZLs-related 7q losses. Gains of 3q and 18q were common to all 3 subtypes. del(8p) was often present together with del(17p) (TP53). Although del(17p) did not determine a worse outcome and del(8p) was only of borderline significance, the presence of both deletions had a highly significant negative impact on the outcome of splenic MZLs.

Anytime Marginal MAP Inference

This paper presents a new anytime algorithm for the marginal MAP problem in graphical models of bounded treewidth. We show asymptotic convergence and theoretical error bounds for any fixed step. Experiments show that it compares well to a state-of-the-art systematic search algorithm.

A multivariate analysis of beta diversity across organisms and environments

We examined variability in hierarchical beta diversity across ecosystems, geographical gradients, and organism groups using multivariate spatial mixed modeling analysis of two independent data sets. The larger data set comprised reported ratios of regional species richness (RSR) to local species richness (LSR) and the second data set consisted of RSR: LSR ratios derived from nested species-area relationships. There was a negative, albeit relatively weak, relationship between beta diversity and latitude. We found only relatively subtle differences in beta diversity among the realms, yet beta diversity was lower in marine systems than in terrestrial or freshwater realms. Beta diversity varied significantly among organisms' major characteristics such as body mass, trophic position, and dispersal type in the larger data set. Organisms that disperse via seeds had highest beta diversity, and passively dispersed organisms showed the lowest beta diversity. Furthermore, autotrophs had lower beta diversity than organisms higher up the food web; omnivores and carnivores had consistently higher beta diversity. This is evidence that beta diversity is simultaneously controlled by extrinsic factors related to geography and environment, and by intrinsic factors related to organism characteristics.

Are Alaskan trees found in locally more favourable sites in marginal areas?

Aim Species generally become rarer and more patchily distributed as the margins of their ranges are approached. We predicted that in such marginal sites, tree species would tend to occur where some key environmental factors are at particularly favourable levels, compensating in part for the low overall suitability of marginal sites.

Location The article considers the spatial distributions of trees in Southeast Alaska (the Alaskan 'panhandle').

Methods We quantified range marginality using spatial distributions of eight tree species across more than one thousand surveyed sites in Southeast Alaska. For each species we derived a site core/margin index using a three-dimensional trend surface generated from logistic regression on site coordinates. For each species, the relationships between the environmental factors slope, aspect and site marginality were then compared for occupied and unoccupied sets of sites.

Results We found that site slope is important for more Alaskan tree species than aspect. Three out of eight had a significant core/margin by occupied/unoccupied interaction, tending to be present in significantly shallower-sloped (more favourable) sites in the marginal areas than the simple core/margin trend predicted. For site aspect, one species had a significant interaction, selecting potentially more favourable northerly aspects in marginal areas. A finer-scale analysis based on the same data came to the same overall conclusions.

Conclusions There is evidence that several tree species in Alaska tend to occur in especially favourable sites in marginal areas. In these marginal areas, these species amplify habitat preferences shown in core areas.

Combining multi-band and frequency-filtering techniques for speech recognition in noisy environments

While current speech recognisers give acceptable performance in carefully controlled environments, their performance degrades rapidly when they are applied in more realistic situations. Generally, the environmental noise may be classified into two classes: the wide-band noise and narrow band noise. While the multi-band model has been shown to be capable of dealing with speech corrupted by narrow-band noise, it is ineffective for wide-band noise. In this paper, we suggest a combination of the frequency-filtering technique with the probabilistic union model in the multi-band approach. The new system has been tested on the TIDIGITS database, corrupted by white noise, noise collected from a railway station, and narrow-band noise, respectively. The results have shown that this approach is capable of dealing with noise of narrow-band or wide-band characteristics, assuming no knowledge about the noisy environment.

Massive stars exploding in a He-rich circumstellar medium - VI. Observations of two distant Type Ibn supernova candidates discovered by La Silla-QUEST

We present optical observations of the peculiar stripped-envelope supernovae (SNe) LSQ12btw and LSQ13ccw discovered by the La Silla-QUEST survey. LSQ12btw reaches an absolute peak magnitude of M-g = -19.3 +/- 0.2, and shows an asymmetric light curve. Stringent pre-discovery limits constrain its rise time to maximum light to less than 4 d, with a slower post-peak luminosity decline, similar to that experienced by the prototypical SN Ibn 2006jc. LSQ13ccw is somewhat different: while it also exhibits a very fast rise to maximum, it reaches a fainter absolute peak magnitude (M-g =-18.4 +/- 0.2), and experiences an extremely rapid post-peak decline similar to that observed in the peculiar SN Ib 2002bj. A stringent pre-discovery limit and an early marginal detection of LSQ13ccw allow us to determine the explosion time with an uncertainty of +/- 1 d. The spectra of LSQ12btw show the typical narrow He I emission lines characterizing Type Ibn SNe, suggesting that the SN ejecta are interacting with He-rich circumstellar material. The He I lines in the spectra of LSQ13ccw exhibit weak narrow emissions superposed on broad components. An unresolved H alpha line is also detected, suggesting a tentative Type Ibn/IIn classification. As for other SNe Ibn, we argue that LSQ12btw and LSQ13ccw likely result from the explosions of Wolf-Rayet stars that experienced instability phases prior to core collapse. We inspect the host galaxies of SNe Ibn, and we show that all of them but one are hosted in spiral galaxies, likely in environments spanning a wide metallicity range.

Diabetic retinopathy:morphometric analysis of basement membrane thickening of capillaries in different retinal layers within arterial and venous environments

AIMS: To assess quantitatively variations in the extent of capillary basement membrane (BM) thickening between different retinal layers and within arterial and venous environments during diabetes.

METHODS: One year after induction of experimental (streptozotocin) diabetes in rats, six diabetic animals together with six age-matched control animals were sacrificed and the retinas fixed for transmission electron microscopy (TEM). Blocks of retina straddling the major arteries and veins in the central retinal were dissected out, embedded in resin, and sectioned. Capillaries in close proximity to arteries or veins were designated as residing in either an arterial (AE) or a venous (VE) environment respectively, and the retinal layer in which each capillary was located was also noted. The thickness of the BM was then measured on an image analyser based two dimensional morphometric analysis system.

RESULTS: In both diabetics and controls the AE capillaries had consistently thicker BMs than the VE capillaries. The BMs of both AE and VE capillaries from diabetics were thicker than those of capillaries in the corresponding retinal layer from the normal rats (p < or = 0.005). Also, in normal AE and VE capillaries and diabetic AE capillaries the BM in the nerve fibre layer (NFL) was thicker than that in either the inner (IPL) or outer (OPL) plexiform layers (p < or = 0.001). However, in diabetic VE capillaries the BMs of capillaries in the NFL were thicker than those of capillaries in the IPL (p < or = 0.05) which, in turn, had thicker BMs than capillaries in the OPL (p < or = 0.005).

CONCLUSIONS: The variation in the extent of capillary BM thickening between different retinal layers within AE and VE environments may be related to differences in levels of oxygen tension and oxidative stress in the retina around arteries compared with that around veins.

Knowledge Exchange, Spatial Analysis & Healthy Urban Environments (KESUE): Project Report

The Knowledge Exchange, Spatial Analysis and Healthy Urban Environments (KESUE) project has extended work previously undertaken by a QUB team of inter-disciplinary researchers engaged with the Physical Activity in the Regeneration of Connswater (PARC) project (Tully et al, 2013). The PARC project focussed on parts of East Belfast to assess the health impact of the Connswater Community Greenway. The KESUE project has aimed to extend some of the tools used initially in East Belfast so that they have data coverage of all of Belfast and Derry-Londonderry. The purpose of this has been to enable the development of evidence and policy tools that link features of the built environment with physical activity in these two cities. The project has used this data to help shape policy decisions in areas such as physical activity, park management, public transport and planning.

Working with a range of local partners who part-funded the project (City Councils in Belfast and Derry-Londonderry, Public Health Agency, Belfast Healthy Cities and Department of Regional Development), this project has mapped all the footpaths in the two cities (covering 37% of the NI population) and employed this to develop evidence used in strategies related to healthy urban planning. Using Geographic Information Systems (GIS), the footpath network has been used as a basis for a wide range of policy-relevant analyses including pedestrian accessibility to public facilities, site options for new infrastructure and assessing how vulnerable groups can access services such as pharmacies. Key outputs have been Accessibility Atlases and maps showing how walkability of the built environment varies across the two cities.

In addition to generating this useful data, the project included intense engagement with potential users of the research, which has led to its continued uptake in a number of policies and strategies, creating a virtuous circle of research, implementation and feedback. The project has proved so valuable to Belfast City Council that they have now taken on one of the researchers to continue the work in-house.

The Cyrenaican Prehistory Project 2011: Late-Holocene environments and human activity from a cave fill in Cyrenaica, Libya

Little is known about late Holocene environmental change in Cyrenaica. The late Holocene sequence in the Haua Fteah, the key regional site, is highly discontinuous and characterised by stable-burning deposits. The geoarchaeology of the late-Holocene cave fill of a small cave, CP1565, located close to the Haua Fteah, is described. The well-stratified sequence, dating from the fourth century AD to the present day, provides a glimpse of life at the bottom of the settlement hierarchy and of changing environments over the last 1600 years, with degraded vegetation and aridity in the ‘Little Ice Age’.

The Robustness of Periodic Orchestrations in Uncertain Evolving Environments

A framework for assessing the robustness of long-duration repetitive orchestrations in uncertain evolving environments is proposed. The model assumes that service-based evaluation environments are stable over short time-frames only; over longer periods service-based environments evolve as demand fluctuates and contention for shared resources varies. The behaviour of a short-duration orchestration E in a stable environment is assessed by an uncertainty profile U and a corresponding zero-sum angel-daemon game Γ(U) [2]. Here the angel-daemon approach is extended to assess evolving environments by means of a subfamily of stochastic games. These games are called strategy oblivious because their transition probabilities are strategy independent. It is shown that the value of a strategy oblivious stochastic game is well defined and that it can be computed by solving a linear system. Finally, the proposed stochastic framework is used to assess the evolution of the Gabrmn IT system.