1,140 research outputs found
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Vibrotactile-auditory interactions are post-perceptual
Vibrotactile stimuli can elicit compelling auditory sensations, even when sound energy levels are minimal and undetectable. It has previously been shown that subjects judge auditory tones embedded in white noise to be louder when they are accompanied by a vibrotactile stimulus of the same frequency. A first experiment replicated this result at four different levels of auditory stimulation (no tone, tone at detection threshold, tone at 5 dB above threshold, and tone at 10 dB above threshold). The presence of a vibrotactile stimulus induced an increase in the perceived loudness of auditory tones at three of the four values in this range. In two further experiments, a 2-interval forced-choice procedure was used to assess the nature of this cross-modal interaction. Subjects were biased when vibrotaction was applied in one interval, but applying vibrotaction in both intervals produced performance comparable to conditions without vibrotactile stimuli. This demonstrates that vibrotaction is sometimes ignored when judging the presence of an auditory tone. Hence the interaction between vibrotaction and audition does not appear to occur at an early perceptual level
Inside the brain of an elite athlete: The neural processes that support high achievement in sports
Events like the World Championships in athletics and the Olympic Games raise the public profile of competitive sports. They may also leave us wondering what sets the competitors in these events apart from those of us who simply watch. Here we attempt to link neural and cognitive processes that have been found to be important for elite performance with computational and physiological theories inspired by much simpler laboratory tasks. In this way we hope to inspire neuroscientists to consider how their basic research might help to explain sporting skill at the highest levels of performance
Spatial attention is not affected by alpha or beta transcranial alternating current stimulation: A registered report
Using Electroencephalography (EEG) an event-related change in alpha activity has been observed over primary sensory cortices during the allocation of spatial attention. This is most prominent during top-down, or endogenous, attention, and nearly absent in bottom-up, or exogenous orienting. These changes are highly lateralised, such that an increase in alpha power is seen ipsilateral to the attended region of space and a decrease is seen contralaterally. Whether these changes in alpha oscillatory activity are causally related to attentional resources, or to perceptual processes, or are simply epiphenomenal, is unknown. If alpha oscillations are indicative of a causal mechanism whereby attention is allocated to a region of space, it remains an open question as to whether this is driven by ipsilateral increases or contralateral decreases in alpha power. This preregistered report set out to test these questions. To do so, we used transcranial Alternating Current Stimulation (tACS) to modulate alpha activity in the somatosensory cortex whilst measuring performance on established tactile attention paradigms. All participants completed an endogenous and exogenous tactile attention task in three stimulation conditions; alpha, sham and beta. Sham and beta stimulation operated as controls so that any observed effects could be attributed to alpha stimulation specifically. We replicated previous behavioural findings in all stimulation conditions showing a facilitation of cued trials in the endogenous task, and inhibition of return in the exogenous task. However, these were not affected by stimulation manipulations. Using Bayes-factor analysis we show strong support for the null hypotheses – that the manipulation of Alpha by tACS does not cause changes in tactile spatial attention. This well-powered study, conducted over three separate days, is an important contribution to the current debate regarding the efficiency of brain stimulation
Methanotrophic Bacteria for Nutrient Removal from Wastewater: Attached Film System
It was hypothesized that nutrient removal from wastewater could be achieved by using methane oxidizing bacteria (methanotrophs). Because methane is inexpensive. it can be used as an energy source to encourage bacterial growth to assimilate nitrogen and phosphorus and other trace elements. This initial feasibility study used synthetic nutrient mixtures and secondary sewage effluent as feed to a laboratory-scale methanotrophic attached-film expanded bed (MAFEB) reactor operated at 35°C and 20°C. The MAFEB system operated successfully at low nutrient concentrations under a variety of nutrient-limited conditions. Using a synthetic nutrient mixture with a nitrogen:phosphorus feed ratio (w/w) of 9:1, phosphate concentrations were reduced from 1.3 mg P/ L to below 0.1 mg P/ L, and ammonia was reduced from 12 mg N/L to approximately 1 mg N/L on a continuous flow basis, with a bed hydraulic retention time of 4.8 hours. The average nutrient uptake rates from synthetic nutrient mixtures were 100 mg nitrogen and 10 mg phosphorus/L of expanded bed/d. Nutrient assimilation rates increased with increasing growth rate and with increasing temperature. Nitrogen/phosphorus uptake ratios varied from 8 to 13, and the observed yield varied from 0.11 to 0.16 g volatile solids (VS)/g chemical oxygen demand (COD). Nutrient removal from secondary sewage effluent was successfully demonstrated using sewage effluent from two local treatment plants. Nutrient concentrations of 10-15 mg N/L and 1.0-1.8 mg P/L were reduced consistently below 1 mg N/L and 0.1 mg P/L. No supplemental nutrients were added to the sewage to attain these removal efficiencies since the nutrient mass ratios were similar to that required by the methanotrophs. Removal rates were lower at 20°C than at 35°C, but high removal efficiencies were maintained at both temperatures. Effluent suspended solids concentrations ranged from 8 to 30 mg volatile suspended solids (VSS)/L, and the effluent soluble COD concentration averaged 30 mg/L
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Biases in the perceived timing of perisaccadic perceptual and motor events
Subjects typically experience the temporal interval immediately following a saccade as longer than a comparable control interval. One explanation of this effect is that the brain antedates the perceptual onset of a saccade target to around the time of saccade initiation. This could explain the apparent continuity of visual perception across eye movements. Thisantedating account was tested in three experiments in which subjects made saccades of differing extents and then judged either the duration or the temporal order of key events. Postsaccadic stimuli underwent subjective temporal lengthening and had early perceived onsets. A temporally advanced awareness of saccade completion was also found, independently of antedating effects. These results provide convergent evidence supporting antedating and differentiating it from other temporal biases
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Rapid de-localization of actin leading edge components with BDM treatment
BACKGROUND: 2,3-Butanedione monoxime (BDM) has been widely used as a non-muscle myosin inhibitor to investigate the role of non-muscle myosinII in the process of actin retrograde flow and other actin cytoskeletal processes. Recent reports show that BDM does not inhibit any non-muscle myosins so far tested, including nm-myosinII, prompting the question, how were these process affected in BDM studies? RESULTS: We have found that treatment of mammalian cells with BDM for only 1 min blocks actin incorporation at the leading edge in a permeabilized cell system. We show that inhibition of actin incorporation occurs through de-localization of leading edge proteins involved in actin polymerization – the Arp2/3 complex, WAVE, and VASP – that de-localize concomitantly with the leading edge actin network. CONCLUSION: De-localization of actin leading edge components by BDM treatment is a newly described effect of this compound. It may explain many of the results previously ascribed to inhibition of non-muscle myosinII by BDM, particularly in studies of leading edge dynamics. Though this effect of BDM is intriguing, future studies probing actin dynamics at the leading edge should use more potent and specific inhibitors
Discussing parenthood with gay men diagnosed with HIV: a qualitative study of patient and healthcare practitioner perspectives.
BACKGROUND: Research on HIV and reproduction has focused largely on women and heterosexual men. This article examines whether it is relevant to address parenthood in HIV care with gay men and what ways of doing so are most appropriate. METHODS: Qualitative interviews were conducted at four London clinics with 25 men living with HIV, aged 20-45, who did not have children, and 16 HIV clinicians. A thematic analysis identified potential reasons why parenthood was rarely discussed with gay men in HIV care. RESULTS: Two sets of ideas contributed to a lack of conversations about parenthood: clinicians' ideas about what matters to gay men and men's ideas about what it means to be HIV-positive. Both sets of ideas largely excluded having children, with patients and practitioners similarly unlikely to raise the topic of parenthood in the clinic. Contrary to what clinician commonly assumed, many men expressed interest in receiving more information, highlighting the importance of reassuring people upon diagnosis that it is possible to become parents while living with HIV. CONCLUSIONS: Parenting desires and intentions were rarely discussed with men in HIV care. Our findings illuminate the potentially beneficial effects of emphasising that having children is a possibility at diagnosis, regardless of patients' gender or sexuality. Conveying this information seems meaningful, not only to men who want to become parents in the future but also to others, as it appears to alleviate fears about mortality and ill health.British HIV Association
Isaac Newton Trust
Leverhulme Trust (ECF-2018-146)
Wellcome Trust (100606/Z/12/Z
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