Chitosan as an antioxidant alternative to sulphites in oenology: EPR investigation of inhibitory mechanisms

The efficacy against oxidative degradation in model and sulphite-free white wines of two commercial, insoluble chitosans (one being approved for winemaking) were investigated by electron paramagnetic resonance (EPR). Both compounds at various doses significantly inhibited the formation of \u3b1-(4-pyridyl-1-oxide)-N-t-butylnitrone (4-POBN)-1-hydroxyethyl adducts under normal wine storage conditions. Pre-incubation with 2 g/L chitosan followed by filtration had a better effect than adding 50 mg/L sulphur dioxide to the experimental Chardonnay wine on the release of 4-POBN adducts after 6 days of incubation with 100 \u3bcM iron(II). In a relevant photooxidative system acetaldehyde formation was significantly reduced after 6 days of incubation. Parallel EPR tests were performed to assess the importance of metal chelation (iron and copper) versus direct scavenging of hydroxyl radicals on the effect of chitosan. The present data support the potentiality of using biocompatible chitosan as a healthier complement and/or alternative to sulphur dioxide against white wine oxidative spoilage

Ecological Energetics of an Abundant Aerial Insectivore, the Purple Martin

We thank T. Fagin for help with estimating the seasonal range area occupied by Purple Martins. We thank an anonymous reviewer, Mark Brigham, and J Boyles for their comments on this manuscript.Conceived and designed the experiments: JFK ESB WFF PBC. Performed the experiments: JFK PBC. Analyzed the data: JFK PBC. Wrote the manuscript: JFK ESB WFF PBC. Developed the model in Matlab: JFK PBC.The atmospheric boundary layer and lower free atmosphere, or aerosphere, is increasingly important for human transportation, communication, environmental monitoring, and energy production. The impacts of anthropogenic encroachment into aerial habitats are not well understood. Insectivorous birds and bats are inherently valuable components of biodiversity and play an integral role in aerial trophic dynamics. Many of these insectivores are experiencing range-wide population declines. As a first step toward gaging the potential impacts of these declines on the aerosphere’s trophic system, estimates of the biomass and energy consumed by aerial insectivores are needed. We developed a suite of energetics models for one of the largest and most common avian aerial insectivores in North America, the Purple Martin (Progne subis). The base model estimated that Purple Martins consumed 412 (± 104) billion insects*y-1 with a biomass of 115,860 (± 29,192) metric tonnes*y-1. During the breeding season Purple Martins consume 10.3 (+ 3.0) kg of prey biomass per km3 of aerial habitat, equal to about 36,000 individual insects*km-3. Based on these calculations, the cumulative seasonal consumption of insects*km-3 is greater in North America during the breeding season than during other phases of the annual cycle, however the maximum daily insect consumption*km-3 occurs during fall migration. This analysis provides the first range-wide quantitative estimate of the magnitude of the trophic impact of this large and common aerial insectivore. Future studies could use a similar modeling approach to estimate impacts of the entire guild of aerial insectivores at a variety of temporal and spatial scales. These analyses would inform our understanding of the impact of population declines among aerial insectivores on the aerosphere’s trophic dynamics.Yeshttp://www.plosone.org/static/editorial#pee

The instrument suite of the European Spallation Source

An overview is provided of the 15 neutron beam instruments making up the initial instrument suite of the European Spallation Source (ESS), and being made available to the neutron user community. The ESS neutron source consists of a high-power accelerator and target station, providing a unique long-pulse time structure of slow neutrons. The design considerations behind the time structure, moderator geometry and instrument layout are presented. The 15-instrument suite consists of two small-angle instruments, two reflectometers, an imaging beamline, two single-crystal diffractometers; one for macromolecular crystallography and one for magnetism, two powder diffractometers, and an engineering diffractometer, as well as an array of five inelastic instruments comprising two chopper spectrometers, an inverse-geometry single-crystal excitations spectrometer, an instrument for vibrational spectroscopy and a high-resolution backscattering spectrometer. The conceptual design, performance and scientific drivers of each of these instruments are described. All of the instruments are designed to provide breakthrough new scientific capability, not currently available at existing facilities, building on the inherent strengths of the ESS long-pulse neutron source of high flux, flexible resolution and large bandwidth. Each of them is predicted to provide world-leading performance at an accelerator power of 2 MW. This technical capability translates into a very broad range of scientific capabilities. The composition of the instrument suite has been chosen to maximise the breadth and depth of the scientific impact o

Re-evaluation of blood mercury, lead and cadmium concentrations in the Inuit population of Nunavik (Québec): a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Arctic populations are exposed to mercury, lead and cadmium through their traditional diet. Studies have however shown that cadmium exposure is most often attributable to tobacco smoking. The aim of this study is to examine the trends in mercury, lead and cadmium exposure between 1992 and 2004 in the Inuit population of Nunavik (Northern Québec, Canada) using the data obtained from two broad scale health surveys, and to identify sources of exposure in 2004.</p> <p>Methods</p> <p>In 2004, 917 adults aged between 18 and 74 were recruited in the 14 communities of Nunavik to participate to a broad scale health survey. Blood samples were collected and analysed for metals by inductively coupled plasma mass spectrometry, and dietary and life-style characteristics were documented by questionnaires. Results were compared with data obtained in 1992, where 492 people were recruited for a similar survey in the same population.</p> <p>Results</p> <p>Mean blood concentration of mercury was 51.2 nmol/L, which represent a 32% decrease (p < 0.001) between 1992 and 2004. Mercury blood concentrations were mainly explained by age (partial r²= 0.20; p < 0.0001), and the most important source of exposure to mercury was marine mammal meat consumption (partial r²= 0.04; p < 0.0001). In 2004, mean blood concentration of lead was 0.19 μmol/L and showed a 55% decrease since 1992. No strong associations were observed with any dietary source, and lead concentrations were mainly explained by age (partial r²= 0.20.; p < 0.001). Blood cadmium concentrations showed a 22% decrease (p < 0.001) between 1992 and 2004. Once stratified according to tobacco use, means varied between 5.3 nmol/L in never-smokers and 40.4 nmol/L in smokers. Blood cadmium concentrations were mainly associated with tobacco smoking (partial r²= 0.56; p < 0.0001), while consumption of caribou liver and kidney remain a minor source of cadmium exposure among never-smokers.</p> <p>Conclusion</p> <p>Important decreases in mercury, lead and cadmium exposure were observed. Mercury decrease could be explained by dietary changes and the ban of lead cartridges use likely contributed to the decrease in lead exposure. Blood cadmium concentrations remain high and, underscoring the need for intensive tobacco smoking prevention campaigns in the Nunavik population.</p

Tinnitus

This article is based on a review of the literature and the experience of some experts. Its goal is to present an overview of the physiopathology of tinnitus and perspectives of treatment based on recent publications. Tinnitus is a problem of society, affecting about 10% of the population. The causes of tinnitus are extremely diverse. Objective tinnitus is generally pulsatile and from arterial or venous origin; subjective tinnitus can be generated at any level of the auditory pathways. Approach to tinnitus includes qualification through anamnesis and specialized questionnaires, and thorough audiological characterization. Sometimes, imaging is indicated as it can reveal the cause of the tinnitus in case of a vascular abnormality or a retro-cochlear tumour. Among the various medications prescribed for tinnitus, only anti-depressants proved to be efficient when secondary depression is present. Hearing aids are useful for hearing impaired patients but the efficiency of tinnitus maskers is not proved. Tinnitus Retraining Therapy is very promising but results must be confirmed by future studies. Studies about neurostimulation are in progress. In the future, better understanding of the physiopathology of tinnitus will lead to new treatments.SCOPUS: re.jinfo:eu-repo/semantics/publishe

Sudden hearing loss

Sudden hearing loss. This update on the latest studies and management policies for patients suffering from sudden sensorineural hearing loss (SSHL) represents a cooperative effort of Belgian ENT surgeons from various corners of the country. SSHL has an incidence ranging from 5 to 20 cases per 100,000 persons per year, and is a relative medical emergency, as only 30% to 65% of the patients recover spontaneously. Nowadays, treatment varies a great deal between countries and hospitals. The various etiologies and therapeutic modalities are reviewed, and evidence levels are indicated. Finally, diagnostic and therapeutic organigrams are proposed along with a Belgian therapeutic cocktail in view of conducting a large Belgian study on the management of SSHL

Ménière's disease

Ménière's disease is an idiopathic inner ear disorder characterized by endolymphatic hydrops (ELH), vertigo attacks, sensorineural hearing loss, tinnitus and pressure sensation in the affected ear. The disorder has to be differentiated from known causes of ELH and from other disorders provoking similar symptoms. Ménière's disease can seriously affect quality of life, and medical support is often necessary on a life long basis. The treatment modalities are counselling, preventive measures and life style adaptation, drug therapy, tinnitus coping, provision of hearing devices, and sometimes surgery. We review the indications for these modalities, and the evidence level of their beneficial effect.SCOPUS: re.jinfo:eu-repo/semantics/publishe