That smells filling: effects of pairings of odours with sweetness and thickness on odour perception and expected satiety

Retronasal co-experience of odours with sweet tastes and thick textures have been shown to result in attribution of sweetness and thickness to odours when they are subsequently sniffed. Orosensory thickness and creaminess are also associated with expectations that a product will be filling. Here we test for the first time whether co-experience of odours with orosensory thickness and sweetness results in transfer of satiety expectations to these odours when subsequently sniffed. Eighty healthy volunteers evaluated the hedonic and sensory characteristics of odours, and expectations that products with the same flavour as the odour would be filling, before and after disguised co-experience of odours with sweetness (sucrose), thickness (tara gum solution) or the combination of sweet/thick, as well as untrained (control) odours. Odours paired with tara gum were subsequently rated as smelling thicker and more creamy, while odours paired with sucrose smelled sweeter. Pairing odours with tara gum increased the expectation that products predicted to have the same flavour as the sniffed odour would be more filling, and this was enhanced by sweetness, while pairing odours with tara-gum increased the expectation that products with that odour would reduce later hunger. Liking for odours paired with sweetness increased, but pairing with thickness alone reduced liking. These data suggest that satiety-consonant sensory characteristics can transfer to associated odours, and that this process is independent of changes in liking. This raises the possibility of using satiety-associated odour cues to manipulate consumer satiety expectations

High temporal resolution records of outdoor and indoor airborne microplastics

There is increasing concern regarding airborne microplastics, but to date, studies have typically used coarse interval sampling (a day or longer) to generate deposition and concentration estimates. In this proof-of-concept study, we used a Burkard volumetric spore trap (intake 10 L min−1; recording airborne particulates onto an adhesive-coated tape moving at 2 mm hr−1) to assess whether this approach has potential to record airborne microplastics at an hourly resolution, thereby providing detailed diurnal patterns. Simultaneous sampling at outdoor and indoor locations at rural and urban sites showed clear daily and weekly patterns in microplastic concentrations which may be related to people and vehicle movement. Indoor residential concentrations of suspected microplastics were the highest (reaching hourly concentrations of 40–50 m−3), whilst rural outdoor concentrations were very low (typically 1–2 m−3 h−1). Whilst the approach shows great potential for high resolution data generation, further development is required for spectroscopic analysis and hence chemical confirmation of visual microplastic identification

On the use of 12CO/13CO as a test of common-envelope evolution

We present K-band echelle spectra of the cataclysmic variable SS Cyg and the pre-cataclysmic variable V471 Tau in order to measure the strengths of the 12CO and 13CO bands at 2.3525 and 2.3448 microns, respectively, and so perform the observational test of the common-envelope model of close binary star evolution proposed by Sarna et al. (1995). Although we find evidence of an absorption feature coincident with the expected wavelength of 13CO in both objects, we attribute it instead to a cluster of neutral atomic absorption features (primarily due to TiI) possibly arising from star-spots on the surfaces of the rapidly rotating secondary stars in these systems, thereby rendering the test inconclusive. We present a modified observational test of common-envelope evolution, based on the observation of the 13CO bands at 2.3739 and 2.4037 microns, which is insensitive to spectral contamination by star-spots

A high-fat high-sugar diet predicts poorer hippocampal-related memory and a reduced ability to suppress wanting under satiety

Animal data indicate that greater intake of fats and sugars prevalent in a Western diet impairs hippocampal memory and tests of behavioral inhibition known to be related to hippocampal function (e.g., feature negative discrimination tasks). It has been argued that such high fat high sugar diets (HFS) impair the hippocampus, which then becomes less sensitive to modulation by physiological state. Thus retrieval of motivationally salient memories (e.g., when seeing or smelling food) occurs irrespective of state. Here we examine whether evidence of similar effects can be observed in humans using a correlational design. Healthy human participants (N = 94), who varied in their habitual consumption of a HFS diet, completed the verbal paired associate (VPA) test, a known hippocampal-dependent process, as well as liking and wanting ratings of palatable snack foods, assessed both hungry and sated. Greater intake of a HFS diet was significantly associated with a slower VPA learning rate, as predicted. Importantly, for those who regularly consumed a HFS diet, while reductions in liking and wanting occurred between hungry and sated states, the reduction in wanting was far smaller relative to liking. The latter effect was strongly related to VPA learning rate, suggestive of hippocampal mediation. In agreement with the animal literature, human subjects with a greater intake of a HFS diet show deficits in hippocampal-dependent learning and memory, and their desire to consume palatable food is less affected by physiological state – a process we suggest that is also hippocampal related

Chemosensory abilities in consumers of a western-style diet

People vary in their habitual diet and also in their chemosensory abilities. In this study we examined whether consumption of a Western-style diet, rich in saturated fat and added sugar, is associated with either poorer or different patterns of chemosensory perception, relative to people who consume a healthier diet. Participants were selected based on a food frequency questionnaire, which established whether they were likely to consume a diet either higher or lower in saturated fat and added sugar. Eighty-seven participants were tested for olfactory ability (threshold, discrimination, identification), gustatory ability (PROP sensitivity, taste intensity, quality and hedonics), and flavour processing (using dairy fat-sugar-odour mixtures). A Western-style diet was associated with poorer odour identification ability, greater PROP sensitivity, poorer fat discrimination, different patterns of sweetness taste enhancement, and hedonic differences in taste and flavour perception. No differences were evident for odour discrimination or threshold, in perception of taste intensity/quality (excluding PROP) or the ability of fats to affect flavour perception. The significant relationships were of small to moderate effect size, and would be expected to work against consuming a healthier diet. The discussion focuses on whether these diet-related differences precede adoption of a Western-style diet and/or are a consequence of it

Artificial coral reefs as a localised approach to increase fish biodiversity and abundance along the North Bali coastline.

Coral reefs face worldwide decline from threats such as climate change, destructive fishing practices, overfishing and pollution. Artificial reefs have shown potential as a method to mitigate localised habitat loss and biodiversity decline on degraded coral reefs. The health of coral reefs in Indonesia and their associated faunal populations have displayed a downward trend in recent decades, and community-managed non-government organisations have started using artificial reefs to restore local degraded reef habitats. In this study, we demonstrate how locally-managed NGOs and communities in north Bali, Indonesia have implemented artificial reef projects, and assess the associated benefits to biodiversity. Using Remote Underwater Video (RUV) over a 3 month period in north Bali, fish assemblages on two artificial reefs of different ages (new and mature) were compared to two nearby natural habitats: degraded sand flats and relatively healthy coral reefs. When compared with a nearby degraded sand habitat, both artificial reefs displayed a significantly higher number of species, which for the mature artificial reef was not statistically different to a nearby coral reef. Community structure was also compared, again showing similarity between artificial reefs and natural coral reefs, but differing in a few species, including specific damselfish and wrasse. This study is one of few which highlight the potential of artificial reef habitat enhancement in Indonesia, and suggests that these structures can provide ecologically equivalent mobile faunal communities to a natural reef on a localised scale. As such, well designed projects may be able to provide some local ecosystem services lost from degraded coral reefs, and become an important focus for coastal communities

Mapping species distributions: A comparison of skilled naturalist and lay citizen science recording

To assess the ability of traditional biological recording schemes and lay citizen science approaches to gather data on species distributions and changes therein, we examined bumblebee records from the UK’s national repository (National Biodiversity Network) and from BeeWatch. The two recording approaches revealed similar relative abundances of bumblebee species but different geographical distributions. For the widespread common carder (Bombus pascuorum), traditional recording scheme data were patchy, both spatially and temporally, reflecting active record centre rather than species distribution. Lay citizen science records displayed more extensive geographic coverage, reflecting human population density, thus offering better opportunities to account for recording effort. For the rapidly spreading tree bumblebee (Bombus hypnorum), both recording approaches revealed similar distributions due to a dedicated mapping project which overcame the patchy nature of naturalist records. We recommend, where possible, complementing skilled naturalist recording with lay citizen science programmes to obtain a nation-wide capability, and stress the need for timely uploading of data to the national repository

Modeling observations of solar coronal mass ejections with heliospheric imagers verified with the Heliophysics System Observatory

We present an advance toward accurately predicting the arrivals of coronal mass ejections (CMEs) at the terrestrial planets, including Earth. For the first time, we are able to assess a CME prediction model using data over two thirds of a solar cycle of observations with the Heliophysics System Observatory. We validate modeling results of 1337 CMEs observed with the Solar Terrestrial Relations Observatory (STEREO) heliospheric imagers (HI) (science data) from 8 years of observations by five in situ observing spacecraft. We use the self-similar expansion model for CME fronts assuming 60 degrees longitudinal width, constant speed, and constant propagation direction. With these assumptions we find that 23%-35% of all CMEs that were predicted to hit a certain spacecraft lead to clear in situ signatures, so that for one correct prediction, two to three false alarms would have been issued. In addition, we find that the prediction accuracy does not degrade with the HI longitudinal separation from Earth. Predicted arrival times are on average within 2.6 +/- 16.6 h difference of the in situ arrival time, similar to analytical and numerical modeling, and a true skill statistic of 0.21. We also discuss various factors that may improve the accuracy of space weather forecasting using wide-angle heliospheric imager observations. These results form a first-order approximated baseline of the prediction accuracy that is possible with HI and other methods used for data by an operational space weather mission at the Sun-Earth L5 point. Plain Language Summary Solar storms are formed by incredibly powerful explosions on the Sun and travel as clouds of plasma threaded by magnetic fields through the solar system. Depending on their propagation direction, they may impact planets such as Earth, where they elicit colorful aurorae or, in very seldom cases, can lead to power failures with potentially tremendous economical and societal effects, thus posing a serious natural hazard. In this work, we have shown how well the solar storm impact can be forecasted when using a special type of instrument that can actually image the solar storms as they propagate toward the planets and even as they sweep over them. Our analysis includes two thirds of a solar cycle with 8 years of data, and spacecraft at Mercury, Venus, Earth, and in the solar wind to check on the correctness of our predictions. We could forecast the arrival time within +/- 16 h, and for one correct impact there are two to three false alarms. This forms a new baseline for the science of space weather prediction. Clearly, the modeling should be further improved to be used on a daily basis for a space weather mission to the Sun-Earth L5 point.Peer reviewe

Cryptic Polyketide Synthase Genes in Non-Pathogenic Clostridium SPP

Modular type I polyketide synthases (PKS) produce a vast array of bacterial metabolites with highly diverse biological functions. Notably, all known polyketides were isolated from aerobic bacteria, and yet no example has been reported for strict anaerobes. In this study we explored the diversity and distribution of PKS genes in the genus Clostridium. In addition to comparative genomic analyses combined with predictions of modular type I polyketide synthase (PKS) gene clusters in sequenced genomes of Clostridium spp., a representative selection of other species inhabiting a variety of ecological niches was investigated by PCR screening for PKS genes. Our data reveal that all studied pathogenic Clostridium spp. are devoid of putative PKS genes. In stark contrast, cryptic PKS genes are widespread in genomes of non-pathogenic Clostridium species. According to phylogenetic analyses, the Clostridium PKS genes have unusual and diverse origins. However, reverse transcription quantitative PCR demonstrates that these genes are silent under standard cultivation conditions, explaining why the related metabolites have been overlooked until now. This study presents clostridia as a putative source for novel bioactive polyketides