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International audience; Equatorial noise emissions (fast magnetosonic waves) are routinely observed in the equatorial region of the inner magnetosphere, propagating nearly perpendicular to the ambient magnetic field. Although most events are continuous in time, some are formed by nearly periodically repeating wave elements. We present a survey of these events with the quasiperiodic time modulation observed by the Cluster and Van Allen Probes spacecraft. Local plasma density measurements are used to evaluate the event locations with respect to the plasmapause. It is shown that although the events may occur both inside and outside the plasmasphere, the occurrence of some events is clearly limited to just outside the plasmasphere, with a sudden disappearance at the plasmapause. The fine frequency structure of the events, which is related to the proton gyrofrequency in the source region, is used to determine the source radial distances. Finally, the analysis of multi-spacecraft measurements allows us to estimate the spatiotemporal variability of the events.

BACKGROUND: There are no disease-modifying treatments for dementia. There is also no consensus on disease modifying outcomes. We aimed to produce the first evidence-based consensus on core outcome measures for trials of disease modification in mild-to-moderate dementia. METHODS AND FINDINGS: We defined disease-modification interventions as those aiming to change the underlying pathology. We systematically searched electronic databases and previous systematic reviews for published and ongoing trials of disease-modifying treatments in mild-to-moderate dementia. We included 149/22,918 of the references found; with 81 outcome measures from 125 trials. Trials involved participants with Alzheimer's disease (AD) alone (n = 111), or AD and mild cognitive impairment (n = 8) and three vascular dementia. We divided outcomes by the domain measured (cognition, activities of daily living, biological markers, neuropsychiatric symptoms, quality of life, global). We calculated the number of trials and of participants using each outcome. We detailed psychometric properties of each outcome. We sought the views of people living with dementia and family carers in three cities through Alzheimer's society focus groups. Attendees at a consensus conference (experts in dementia research, disease-modification and harmonisation measures) decided on the core set of outcomes using these results. Recommended core outcomes were cognition as the fundamental deficit in dementia and to indicate disease modification, serial structural MRIs. Cognition should be measured by Mini Mental State Examination or Alzheimer's Disease Assessment Scale-Cognitive Subscale. MRIs would be optional for patients. We also made recommendations for measuring important, but non-core domains which may not change despite disease modification. LIMITATIONS: Most trials were about AD. Specific instruments may be superseded. We searched one database for psychometric properties. INTERPRETATION: This is the first review to identify the 81 outcome measures the research community uses for disease-modifying trials in mild-to-moderate dementia. Our recommendations will facilitate designing, comparing and meta-analysing disease modification trials in mild-to-moderate dementia, increasing their value. TRIAL REGISTRATION: PROSPERO no. CRD42015027346.

Purpose : The PrOVIDe study aimed to investigate the prevalence of a range of vision problems among people with dementias, aged 60-89 years and to examine the extent to which these conditions are undetected or inappropriately managed.\ud \ud Methods : The study had two stages, a cross-sectional prevalence study followed by qualitative research. In Stage 1, 708 people with dementia (389 living at home and 319 in care homes) had a domiciliary eye examination. The inclusion criteria were people with dementia (any type), aged 60-89 years; individuals lacking mental capacity to provide informed consent to participate required a consultee who could give approval on their behalf.\ud \ud Results : 22 percent reported not having had a test in the last two years: this included 19 participants who had not been tested in the last 10 years. Prevalence of visual impairment (VI) was 32.4% (95% Confidence Intervals (CI) 28.7 to 36.5) and 16.3% (CI 13.5 to 19.6) for the commonly-used criteria for VI of visual acuity (VA) worse than 6/12 and 6/18 respectively. Of those with VI, 44% (VA

Insect pests can reduce wheat yield by direct feeding and transmission of plant\ud viruses. Here we report results from laboratory and field phenotyping studies\ud on a wide range of wheat, including landraces from the Watkins collection\ud deriving from before the green revolution, more modern cultivars from the\ud Gediflux collection (north-western Europe) and modern UK Elite varieties,\ud for resistance to the bird cherry-oat aphid, Rhopalosiphum padi (Homoptera:\ud Aphididae) and the English grain aphid, Sitobion avenae (Homoptera: Aphididae).\ud A total of 338 lines were screened for R. padi and 340 lines for S. avenae.\ud Field trials were also conducted on 122 Watkins lines to identify wheat bulb\ud fly, Delia coarctata, preference on these landraces. Considerable variation was\ud shown in insect performance among and within different wheat collections,\ud with reduced susceptibility in a number of varieties, but phenotyping did not\ud identify strong resistance to aphids or wheat bulb fly. Field trials showed within\ud collection differences in aphid performance, with fewer aphids populating lines\ud from the Watkins collection. This differs from development data in laboratory\ud bioassays and suggests that there is a pre-alighting cue deterring aphid settlement\ud and demonstrates differences in aphid preference and performance on\ud older plants in the field compared with seedlings in the laboratory, highlighting\ud the need for phenotyping for aphid resistance at different plant growth stages.\ud No association was identified between performance of the different insect\ud species on individual varieties, potentially suggesting different nutritional\ud requirements or resistance mechanisms.

Measures of the acoustic reflex were obtained on 15 college students with moderate to severe, long-term sensorineural loss. (Author)

The paper was presented at the International Conference on Communications of the Institute of Electrical and Electronics Engineers, Held in Boulder, Colorado, June 9-11, 1969. (Author)

Presented in part at the Meeting of the Acoustical Society of America (75th, Ottawa, Canada, May, 1968). (Author)

Paper presented at the Meeting of Scandinavian Acoustical Society (Trondheim, Norway, May, 1968), and the Meeting of the Acoustical Society of America (75th, Ottawa, Canada, May, 1968). (Author)

International audience; Equatorial noise (EN) emissions are electromagnetic waves routinely observed in the inner magnetosphere within a few degrees from the geomagnetic equator. They propagate in the extraordinary mode nearly perpendicular to the ambient magnetic field, i.e., their frequencies are approximately limited by the lower hybrid frequency. Although they are usually continuous in time, about 5 percent of the events exhibit a clear quasiperiodic modulation of the wave intensity. We analyze in total 118 such EN events measured by the Cluster spacecraft. It is shown that more intense events typically have lower modulation periods. The fine harmonic structure identifiable when high resolution data are available allows us to estimate the radial distance of their source. We analyze in situ measured particle distribution functions and magnetic field pulsations in an attempt to determine the origin of the observed intensity variations. Finally, we use the data from the low altitude satellite DEMETER to demonstrate that these emissions can be observed at altitudes as low as 700 km, in particular during geomagnetically disturbed periods.

International audience; Earth is an intense radio source in the kilometer wavelength range. Being a direct consequence of the parallel acceleration processes taking place in the Earth's auroral region, the radiation contains fundamental information on the characteristic spatial and temporal scales of the turbulent accelerating layer. It is now widely assumed that the cyclotron maser instability leads to Auroral Kilometric Radiation (AKR) generation. It has been suggested from the FAST measurements that the AKR results from a so-called horseshoe electron distribution. This distribution is generated when a localized parallel electric field - called Double Layer (DL) - accelerates earthward the electrons that propagate into an increasing magnetic field. The magnetic moment of the electrons is conserved so that their pitch angle is increased. This results in the creation of a horseshoe-like shape for the electron distribution exhibiting large positive velocity gradients in the direction perpendicular to B, thereby providing free energy for the AKR generation which takes place at the local electron gyrofrequency. In these circumstances, the radiation is generated far away (several thousand kilometers) from a DL, because the parallel accelerated electrons need to travel a long distance before forming a horseshoe distribution. From an experimental point of view, it is not an easy task to highlight the presence of DLs, because they are moving transient structures so that high time resolution measurements are needed. A detailed analysis suggests that these large-amplitude parallel electric fields are located inside sharp density gradients at the interface separating the cold, dense ionospheric plasma from the hot, tenuous magnetospheric plasma. We present some FAST observations which illustrate the generation of elementary radiation events in the neighborhood of a DL. The events occur 10 to 20% above the local electron gyrofrequency in association with the presence of nonlinear coherent structures (such as electron holes) located on the high potential side of the DL. These observational results might encourage investigation of such radiating processes because they could be relevant to other astrophysical radio sources, such as the recently discovered aurora around a brown dwarf.

BACKGROUNDAgrilus bigutattus (Fabricius) is a forest pest of increasing importance in the United Kingdom. The larvae damage weakened native oaks and are thought to contribute to premature tree death. Suspected links with acute oak decline (AOD) are not yet confirmed, but AOD-predisposed trees appear to become more susceptible to A. biguttatus attack. Thus, management may be necessary for control of this insect. To explore the possibility of monitoring beetle populations by baited traps, the host tree volatiles regulating A. biguttatus-oak interactions were studied. RESULTSBiologically active volatile organic compounds in dynamic headspace extracts of oak foliage and bark were identified initially by coupled gas chromatography-electroantennography (GC-EAG) and GC-mass spectrometry (GC-MS), and the structures were confirmed by GC coinjection with authentic compounds. Of two synthetic blends of these compounds comprising the active leaf volatiles, the simpler one containing three components evoked strongly positive behavioural responses in four-arm olfactometer tests with virgin females and males, although fresh leaf material was more efficient than the blend. The other blend, comprising a five-component mixture made up of bark volatiles, proved to be as behaviourally active for gravid females as bark tissue. CONCLUSIONSThese initial results on A. biguttatus chemical ecology reveal aspects of the role of attractive tree volatiles in the host-finding of beetles and underpin the development of semiochemically based surveillance strategies for this forest insect. (c) 2015 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

International audience; Equatorial noise (EN) emissions are electromagnetic waves at frequencies between the proton cyclotron frequency and the lower hybrid frequency routinely observed in the equatorial region of the inner magnetosphere. They propagate in the extraordinary mode nearly perpendicular to the ambient magnetic field, and they exhibit a harmonic structure related to the ion cyclotron frequency in the source region. We analyze more than 2000 EN events observed by the wave instruments on board the Cluster spacecraft, and we find that about 5% of EN events are not continuous in time, but exhibit a quasi-periodic (QP) modulation of the wave intensity. Typical modulation periods are on the order of minutes. The events predominantly occur in the noon-to-dawn local time sector, and their occurrence is related to the periods of increased geomagnetic activity and higher solar wind speeds. We suggest that the QP modulation of EN events may be due to compressional ULF pulsations, which periodically modulate the wave growth in the source region. These compressional ULF pulsations were identified in about half of the events. Finally, we demonstrate that EN emissions with QP modulation of the wave intensity can propagate down to altitudes as low as 700 km.

International audience

International audience; Equatorial noise (EN) emissions are electromagnetic waves at frequencies between the proton cyclotron frequency and the lower hybrid frequency observed routinely in the equatorial region of the inner magnetosphere. They propagate in the extraordinary mode nearly perpendicular to the ambient magnetic field. Although their harmonic structure, which is characteristic of the proton cyclotron frequency in the source region has been known for a couple of decades, they were generally believed to be continuous in time. The analysis of more than 2000 EN events observed by the STAFF-SA and WBD instruments on board the Cluster spacecraft reveals that this is not always the case, with about 5% of events exhibiting a clear quasi-periodic (QP) modulation of the wave intensity. We perform a systematic analysis of these events, and we discuss possible mechanisms of the QP intensity modulation. It is shown that the events occur usually in the noon-to-dawn magnetic local time sector, and their occurrence seems to be related to the periods of increased geomagnetic activity. The modulation period of these events is on the order of minutes. Compressional ULF magnetic field pulsations with periods about double the modulation periods of EN were identified in about half of the events. These ULF pulsations might modulate the EN wave intensity, similarly as they modulate the intensity of formerly reported VLF whistler-mode QP events.

A synthetic biology approach to the rational design of analogues of olfactory ligands by providing unnatural substrates for the enzyme synthesising (S)-germacrene D, an olfactory ligand acting as a plant derived insect repellent, to produce novel ligands is described as a viable alternative to largely unsuccessful ligand docking studies. (S)-14,15-Dimethylgermacrene D shows an unexpected reversal in behavioural activity.