NH3 biofiltration of piggery air.

An aboveground pilot-scale biofilter filled with wood chips was tested to treat ammonia emissions from a piggery located in Brittany (France). Two long-term tests ("summer" and "autumn" experiments) were carried out to improve biofilter applications for agriculture. The influence of climatic conditions on biofilter performance was taken into account. During summer 2012, the biofilter was operated for 74 days at different empty bed residence times (EBRTs) from 6 to 15 s. Inlet NH3 concentrations were relatively constant (around 15 mg m(-3)). Significant NH3 reductions were achieved at EBRT = 12 s (removal efficiencies, RE, ranged between 90 and 100% for loading rates, LR, of around 4 g m(-3) h(-1)). At a lower EBRT (6 s), RE dropped to roughly 30-50%. This was due to the dramatic increase in the loading rate (LR up to 12 g m(-3) h(-1)) but the results showed that the change in atmospheric conditions (temperature and relative humidity) also had a significant influence on biofilter performance. It was evidenced that the use of a humidifier upstream of the biofilter must be taken into account for large-scale biofilter design, but only for specific conditions (the spraying of the biofilter having to be carried out exceptionally). During autumn 2012, the biofilter was operated for 116 days at EBRT = 12 s. RE were around 80% for LR of around 3 g m(-3) h(-1). In such autumnal atmospheric conditions, a demister system should be installed upstream of the biofilter in order to avoid water accumulation in the bed material. Although biofiltration was suitable for NH3 treatment of piggery air, the need to control accurately the medium moisture content implies that biofilters would not be easily managed by a pig farmer.

Linking MRI to daily life experience: the example of poststroke depression.

OBJECTIVE: The state-of-the-art tools of neurology, in particular modern neuroimaging techniques, have yet to benefit from the revolution in mobile technologies that provide new insights into the mechanisms underlying clinical syndromes. This study demonstrates the manner in which mobile technologies may provide information that is complementary to MRI data, using the illustration of poststroke depression. METHODS: MRI examinations were provided to 15 stroke patients, followed by computerized ambulatory monitoring of daily life experiences over 1 week. RESULTS: The occurrence of daily life events was significantly associated with the intensity of positive affect during the ambulatory monitoring period. This emotional reactivity was also significantly associated with functional connectivity in brain regions linked with the risk of depression 3 months following stroke. CONCLUSIONS: Novel mobile technologies provide information that is inaccessible to hospital-based tests, and allow for more complete investigations of disorder expression and etiology.

[Effect of a hearing aid on progressive hearing loss]. / Impact de l'amplification prothétique sur les surdités evolutives.

A group of 72 children with hearing aids followed in 4 different clinical settings presented progressive increase in sensorineural hearing loss. The mean hearing loss over time, the duration of hearing aid use and the gain were studied to test the hypothesis that continued progression in hearing loss was due to overly powerful amplification. No correlation was found between the progressive increased gain levels were associated with less progression in hearing loss than at lower gain levels. Therefore, the use of hearing aids was not directly and significantly related to the increase in hearing loss in the population studied. However according to the above criteria a few cases (4%) of progressive hearing loss did seem to be associated with hearing aid use.