Role of microbes in controlling the speciation of arsenic and production of arsines in contaminated soils

The influence of microbes on the speciation of arsenic and production of arsines in contaminated soils was investigated under laboratory conditions. Microbes were able to carry out reactions that resulted in changes in the speciation of arsenic in soil. The transformation of soil dominating species, arsenate [As(V)], under both aerobic and anaerobic conditions to arsenite [As(III)], monomethylarsonic acid [MMAA], dimethylarsinic acid [DMAA] and to volatile trimethylarsine [TMA] was, however, less than 0.5%, of which the production of TMA represented 0.02-0.3%. The volatilization process was also verified in the field, in the soil of a dumping area. The 'life-time' of arsines in air was, however, short and they were rapidly converted back to water soluble species, As(V) and trimethyl arsine oxide (TMAO).     

Selection of NF membrane to improve quality of chemically treated surface water

The requirement for higher quality drinking water necessitates the application of more efficient water treatment techniques. Nanofiltration is one promising option for enhanced water treatment, for example, in enhanced organic matter removal. The characteristics of different nanofiltration membranes vary remarkably, and the selection of a membrane has to be made according to the requirements of an application. In this study six nanofiltration membranes (NF70, NF255, NTR-7450, NTR-7410, Desal-5 and TFC-S) were evaluated in improving the quality of chemically pre-treated surface water in a pilot-scale process. The results indicate that the membrane with high organics removal and slightly reduced ion removal characteristics (NF255) performed best in terms of product water quality as well as membrane productivity and fouling. The most permeable membrane (NTR-7410) suffered intensive fouling and insufficient product water quality. An interesting finding was that the permeates of all the tested membranes possessed a significant potential for microbial growth, despite the low nutrient contents.     

Spontaneous healing of a massive tibial cortical defect

BACKGROUND: Intraocular cilia present clinical perplexity due to their radiolucency, the extremely variable ocular response to such cilia, and the inadvisability of using MRI in cases of suspected metallic intraocular foreign bodies (IOFB). METHODS: Two cases of intravitreal cilia associated with phakic penetrating eye injury are described where preoperative CT scan revealed no retained IOFB. RESULTS: B-scan ultrasonography detected intravitreal cilia in one patient and raised this suspicion in the other. One patient presented with endophthalmitis unresponsive to intravitreal antibiotics, the other with culture-negative anterior uveitis. Both underwent vitrectomy and removal of cilia. CONCLUSIONS: Intravitreal cilia should be considered in penetrating eye injuries even in phakic eyes with no radiological evidence of IOFB, especially if associated with endophthalmitis. B-scan ultrasonography may aid detection of intravitreal cilia and thus alter clinical management.     

Templating Effects in the Dynamic Chemistry of Cucurbiturils and Hemicucurbiturils

This review concentrates on the remarkable macrocyclisation chemistry of cucurbituril family members. During a single step in the condensation reaction of cucurbit[6]uril or hemicucurbit[12]uril 24 new C−N bonds are formed. In the case of hemicucurbit[12]uril this leads to the highly efficient formation of a covalently bound chain of 48 atoms. This phenomenon is possible because all cucurbiturils are built up of dynamic covalent acylaminal linkers. Moreover, the reversibility of acylaminal linkages makes the formation of macrocycles susceptible to external stimuli. Influence of the chain-growth and chain-cycle equilibrium and the effect of different templates in CB chemistry is discussed. As anions have a pronounced effect on formation of hemicucurbiturils, a comprehensive overview on their role in modifying the solid-state structures of hemicucurbiturils is given.     

Impact of Oil Shale Mining on Flow Regimes in Northeast Estonia

In addition to the well-documented effects of aquatic pollution, mining operations can have major impacts on hydrological pathways and flow regime in downstream catchments. This paper documents long term (1923–2008) changes in surface drainage areas and runoff characteristics in two small to medium (100–1,000 km²) rivers draining part of the Ordovician oil shale field of north east Estonia. Through coupling analysis of flow regime with mining records (discharge rates and workings locations) the impact of expansion in oil shale mining through the mid to late twentieth century on downstream flow is assessed. During phases of intense mining, winter and summer baseflow is between 53 and 72% higher than long term average baseflow in the Purtse catchment and between 66 and 92% higher in the smaller Pühajõgi catchment where the volumetric significance of mine discharges is greater. The contribution of pumped deeper groundwater to surface run-off is shown to control the largest increases in mean annual run-off. While flow augmentation is the most common hydrological impact of the mining operations, phases of dehydration are also recognised in streams where cross-watershed transfers reduce the effective catchment area. Implications of the changed flow regime on river quality and management options are considered.     

Future endovascular management of cerebral aneurysms

The endovascular management of cerebral aneurysms is undergoing revolutionary growth. Recent advances in endovascular surgery including balloon remodeling, revascularization techniques, functional cerebral rearrangement, intracranial stents, treatment for vasospasm and coil design are discussed, as are their future considerations.     

Transient Receptor Potential Ankyrin 1 (TRPA1) Is Involved in Upregulating Interleukin-6 Expression in Osteoarthritic Chondrocyte Models

Transient receptor potential ankyrin 1 (TRPA1) is a membrane-bound ion channel found in neurons, where it mediates nociception and neurogenic inflammation. Recently, we have discovered that TRPA1 is also expressed in human osteoarthritic (OA) chondrocytes and downregulated by the anti-inflammatory drugs aurothiomalate and dexamethasone. We have also shown TRPA1 to mediate inflammation, pain, and cartilage degeneration in experimental osteoarthritis. In this study, we investigated the role of TRPA1 in joint inflammation, focusing on the pro-inflammatory cytokine interleukin-6 (IL-6). We utilized cartilage/chondrocytes from wild-type (WT) and TRPA1 knockout (KO) mice, along with primary chondrocytes from OA patients. The results show that TRPA1 regulates the synthesis of the OA-driving inflammatory cytokine IL-6 in chondrocytes. IL-6 was highly expressed in WT chondrocytes, and its expression, along with the expression of IL-6 family cytokines leukemia inhibitory factor (LIF) and IL-11, were significantly downregulated by TRPA1 deficiency. Furthermore, treatment with the TRPA1 antagonist significantly downregulated the expression of IL-6 in chondrocytes from WT mice and OA patients. The results suggest that TRPA1 is involved in the upregulation of IL-6 production in chondrocytes. These findings together with previous results on the expression and functions of TRPA1 in cellular and animal models point to the role of TRPA1 as a potential mediator and novel drug target in osteoarthritis.     

Bringing planning to the streets: using site-specific video as a method for participatory urban planning

This article examines videographic planning visualizations and their potential to enrich the modes of communication and participation in urban planning. As a case study, the article introduces a research project conducted in the residential area of Pansio-Perno, in Turku, Finland, where a set of site-specific planning videos was made in collaboration with professional artists. A spatio-visual approach was employed to study the different sites for making the videos, including the sites of video production, the contents of the planning videos, and sites for video presentations. Residents were able to take part in the project by voting between different urban development alternatives with the help of on-site mobile technology. Presenting the results of the participation in public made the process more open, transparent, and visible to local people. Appealing planning visualizations, as well as easily accessible participation methods, are therefore proposed here as a means to improve the approachability and diversity of planning communication.     

Root exudates of a legume tree as a nitrogen source for a tropical fodder grass

Exudation of nitrogenous compounds from the roots of dinitrogen-fixing plants is a potential source of nitrogen for adjacent plants in intercropping systems. We studied (1) the extent of N exudation from the roots of a tropical legume tree Gliricidia sepium (Jacq.) Kunth ex Walp., and (2) the ability of a C4 fodder grass Dichantium aristatum (Poir) C.E. Hubbard and its mycorrhizal symbionts to absorb N from tree exudates in a glasshouse experiment. Root exudates of ¹⁵N-labelled trees were collected in hydroponic culture and applied with irrigation water on grass grown in separate pots. During the 10-week experiment, the trees exuded 34.1 ± 5.0 mg of N, which represented 1.7 ± 0.2% of their total N by the end of the experiment. The total amount exuded would have been enough to supply 16% of grass N content by the end of the experiment. The grass, however, absorbed only 3.8–7.5% of ¹⁵N in exudates and gained 0.8–1.1% of its N from exudates. The low absorption of exudate N by grass was explained by probable soil microbial immobilisation and by the dilution of exuded N in the substantially larger pool of soil mineral N. A close contact between the root systems of N donor and recipient plants directly or via their mycorrhizal symbionts seems to be a precondition of the apparently direct N transfer earlier observed in field studies of the same soil-plant system.     

Organic acid catalyzed synthesis of 5-methylresorcinol based organic aerogels in acetonitrile

A method of preparing 5-methylresorcinol and formaldehyde based organic aerogels in non-aqueous media with a benzoic acid derivative as a catalyst is being proposed in this paper. Here acetonitrile is used as a solvent that allows direct drying with carbon dioxide over the supercritical state without the need for a solvent exchange. The acidic properties of 2,6-dihydroxy-4-methyl benzoic acid promote the reaction of sol–gel polymerization, and at the same time it takes part in the reaction as a co-monomer and influences the nanostructure of the material. The evolution of the polymer was monitored using nuclear magnetic resonance spectroscopy and the structure of the resulting organic aerogels depending on the molar ratio of 5-methylresorcinol to 2,6-dihydroxy-4-methyl benzoic acid was studied by nitrogen adsorption–desorption measurements, scanning electron microscopy and infrared spectrometry.