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Can auditory objects be subitized?
In vision, humans have the ability to mentally 'tag' approximately four objects, allowing us to monitor, attend, and interact with them. As a consequence, we can rapidly and accurately enumerate up to four objects – a process known as subitizing. Here, we investigate whether a similar ability exists for tagging auditory stimuli and find that only two or three auditory stimuli can be enumerated with high accuracy. We assess whether this high accuracy indicates the existence of an auditory subitizing mechanism, and if it is influenced by factors known to influence visual subitizing. Based on accuracy, Experiments 1 and 2 reveal a potential auditory subitizing mechanism only when stimuli are spatially separated, as is the case for visual subitizing. Experiment 3 failed to show any evidence of auditory subitizing when objects were separated in time, rather than space. All three experiments provide only limited evidence for an age-related decline in auditory enumeration of small numbers of objects. This suggests that poor auditory tagging does not contribute significantly to older adults’ difficulties in multi-talker conversations. We hypothesize that although auditory subitizing might occur, it is restricted to approximately two spatially-separated objects due to the difficulty of parsing the auditory scene into its constituent parts
'For this I was made': conflict and calling in the role of a woman priest
There has been an increasing focus on ‘work as calling’ in recent years, but relatively few empirical sociological accounts that shed light on the experience of performing calling work. Although callings have generally been referred to as positive and fulfilling to the individual and as beneficial to society, researchers have also suggested there is a ‘dark side’ to calling, and have drawn attention to the potential conflicts and tensions inherent in the pursuit of calling, especially for women. This article explores these themes through the first-hand experiences of one woman who felt called to work as a priest. Her narrative illustrates how callings draw the individual irresistibly towards a particular line of work. It also shows how calling work can be both satisfying individually and beneficial to the wider community but, at the same time, involves sacrifice, compromise and a willingness to defer personal rewards
Effect of nickel on the microstructure and mechanical property of die-cast Al–Mg–Si–Mn alloy
The effect of nickel on the microstructure and mechanical properties of a die-cast Al–Mg–Si–Mn alloy has been investigated. The results show that the presence of Ni in the alloy promotes the formation of Ni-rich intermetallics. These occur consistently during solidification in the die-cast Al–Mg–Si–Mn alloy across different levels of Ni content. The Ni-rich intermetallics exhibit dendritic morphology during the primary solidification and lamellar morphology during the eutectic solidification stage. Ni was found to be always associated with iron forming AlFeMnSiNi intermetallics, and no Al3Ni intermetallic was observed when Ni concentrations were up to 2.06 wt% in the alloy. Although with different morphologies, the Ni-rich intermetallics were identified as the same AlFeMnSiNi phase bearing a typical composition of Al[100–140](Fe,Mn)[2–7]SiNi[4–9]. With increasing Ni content, the spacing of the α-Al–Mg2Si eutectic phase was enlarged in the Al–Mg–Si–Mn alloy. The addition of Ni to the alloy resulted in a slight increase in the yield strength, but a significant decrease in the elongation. The ultimate tensile strength (UTS) increased slightly from 300 to 320 MPa when a small amount (e.g. 0.16 wt%) of Ni was added to the alloy, but further increase of the Ni content resulted in a decrease of the UTS.The Engineering and Physical Sciences Research Council (EPSRC), Technology Strategy Board (TSB) and Jaguar Land Rover (JLR) in the United Kingdom
Possible modulation of concurrent Parkinson’s disease in the management of metastatic GIST: a review of two cases
Imatinib, a tyrosine kinase inhibitor, is the mainstay of treatment for resected high-risk (adjuvant and metastatic) gastrointestinal stromal tumour (GIST) – a rare form of sarcoma. There has been recent research into the neuroprotective role and modulation of dopaminergic neurones by imatinib through the abl pathway in Parkinson’s disease (PD). We describe two patients from a single cancer centre with concurrent diagnoses of PD and metastatic GIST receiving imatinib and standard PD management. The cases highlight a potential reduction in PD progression using Unified Parkinson’s Disease Rating Scale. Further research into repurposing of imatinib for PD may provide additional management options for this neurodegenerative illness
Identification of Novel Metabolic Pathways of Sitagliptin (STG) by LC/MS and LC/MS2 after Incubations with Rat Hepatocytes
Sitagliptin (STG), a drug for treating Type Ii Diabetes Mellitus (T2DM), has been associated with severe joint pain in some patients. In this paper the metabolic profile of the drug has been investigated in order to determine metabolism and formation of reactive compounds which may contribute to this adverse effect. Metabolism of STG was investigated in vitro by incubation with freshly isolated Sprague-Dawley rat hepatocytes, to characterize Phase I and II metabolites, and the reaction mixture analysed on a zwitter ionic hydrophilic interaction (ZIC®-HILIC) column using LC-MS and LC-MS2 utilising electrospray ionization (ESI) in the positive ion mode. STG was metabolised to yield eleven metabolites, but in total only 3.1% of the parent drug was metabolised over 2 hrs incubation. These metabolites were structurally characterized on the basis of accurate mass analyses and the major metabolic routes for STG determined to be via aromatic oxidation (0.86%) and desaturation of N-C and C-C of the piperazine (0.44%). Novel metabolites of STG detected using these methods included STG N-glucuronide (M6) and a di-ketone metabolite (M4), hydroxylation of both the amine group and aromatic ring followed by formation of glucuronide metabolites (M5, M5’), oxidative desaturation of NH2 and di-hydroxylation of metabolites followed by loss of HF. Also, observed was an N-sulfate metabolite (0.07%) and acetylation followed by glucuronide conjugation was also found in trace amounts (<0.01%). MS2 fragment ions provide additional structural confirmation providing a possible structure for most metabolites such as by fragment ion loss of the glucuronide group (176 Da) from metabolite M5 and loss of the phenolic sulfate (80 Da) of N-Sulfate metabolite (M7). Reduction reaction of piperazine ring probably generates highly electrophilic metabolite of STG, which may be susceptible to produce adverse effects. Furthermore, N-oxidation reaction forming reactive intermediates metabolic to give a hydroxylamine metabolite that may undergo further reactions to yield electrophilic intermediate metabolites
Aging and Visual Counting
Much previous work on how normal aging affects visual enumeration has been focused on the response time required to enumerate, with unlimited stimulus duration. There is a fundamental question, not yet addressed, of how many visual items the aging visual system can enumerate in a "single glance", without the confounding influence of eye movements.We recruited 104 observers with normal vision across the age span (age 21-85). They were briefly (200 ms) presented with a number of well- separated black dots against a gray background on a monitor screen, and were asked to judge the number of dots. By limiting the stimulus presentation time, we can determine the maximum number of visual items an observer can correctly enumerate at a criterion level of performance (counting threshold, defined as the number of visual items at which ≈63% correct rate on a psychometric curve), without confounding by eye movements. Our findings reveal a 30% decrease in the mean counting threshold of the oldest group (age 61-85: ∼5 dots) when compared with the youngest groups (age 21-40: 7 dots). Surprisingly, despite decreased counting threshold, on average counting accuracy function (defined as the mean number of dots reported for each number tested) is largely unaffected by age, reflecting that the threshold loss can be primarily attributed to increased random errors. We further expanded this interesting finding to show that both young and old adults tend to over-count small numbers, but older observers over-count more.Here we show that age reduces the ability to correctly enumerate in a glance, but the accuracy (veridicality), on average, remains unchanged with advancing age. Control experiments indicate that the degraded performance cannot be explained by optical, retinal or other perceptual factors, but is cortical in origin
A pilot telephone intervention to increase uptake of breast cancer screening in socially deprived areas in Scotland (TELBRECS):study protocol for a randomised controlled trial
BACKGROUND Breast cancer accounts for almost 30% of all cancers and is the second leading cause of cancer deaths in women in Scotland. Screening is key to early detection. The Scottish Breast Screening Programme is a nationwide, free at point of delivery screening service, to which all women aged between 50 and 70 years are invited to attend every 3 years. Currently over three-quarters of invited women regularly attend screening. However, women from more deprived areas are much less likely to attend: for example in the 3 years from 2010-2012 only 63% of women in the most deprived area attended the East of Scotland Breast Screening programme versus 81% in the least deprived. Research has suggested that reminders (telephone or letter) and brief, personalised interventions addressing barriers to attendance may be helpful in increasing uptake in low-income women. METHODS/DESIGN We will employ a brief telephone reminder and support intervention, whose purpose is to elicit and address any mistaken beliefs women have about breast screening, with the aim that the perceived benefits of screening come to outweigh any perceived barriers for individuals. We will test whether this intervention, plus a simple anticipated regret manipulation, will lead to an increase in the uptake of breast cancer screening amongst low-income women who have failed to attend a first appointment, in a randomised controlled trial with 600 women. Participants will be randomly allocated to one of four treatment arms i.e. 1) Letter reminder (i.e. Treatment as usual: CONTROL); 2) Telephone reminder (TEL), 3) Telephone reminder plus telephone support (TEL-SUPP) and 4) Telephone reminder plus support plus AR (TEL-SUPP-AR). The primary outcome will be attendance at breast screening within 3 months of the reminder letter. DISCUSSION If this simple telephone support intervention (with or without AR intervention) leads to a significant increase in breast screening attendance, this would represent a rare example of a theoretically-driven, relatively simple psychological intervention that could result in earlier detection of breast cancer amongst an under-served group of lower socio-economic women. TRIAL REGISTRATION Current Controlled trials: ISRCTN06039270. Registered 16th January 2014
Comparisons against baseline within randomised groups are often used and can be highly misleading
<p>Abstract</p> <p>Background</p> <p>In randomised trials, rather than comparing randomised groups directly some researchers carry out a significance test comparing a baseline with a final measurement separately in each group.</p> <p>Methods</p> <p>We give several examples where this has been done. We use simulation to demonstrate that the procedure is invalid and also show this algebraically.</p> <p>Results</p> <p>This approach is biased and invalid, producing conclusions which are, potentially, highly misleading. The actual alpha level of this procedure can be as high as 0.50 for two groups and 0.75 for three.</p> <p>Conclusions</p> <p>Randomised groups should be compared directly by two-sample methods and separate tests against baseline are highly misleading.</p
Mapping an atlas of tissue-specific drosophila melanogaster metabolomes by high resolution mass spectrometry
Metabolomics can provide exciting insights into organismal function, but most work on simple models has focussed on the whole organism metabolome, so missing the contributions of individual tissues. Comprehensive metabolite profiles for ten tissues from adult Drosophila melanogaster were obtained here by two chromatographic methods, a hydrophilic interaction (HILIC) method for polar metabolites and a lipid profiling method also based on HILIC, in combination with an Orbitrap Exactive instrument. Two hundred and forty two polar metabolites were putatively identified in the various tissues, and 251 lipids were observed in positive ion mode and 61 in negative ion mode. Although many metabolites were detected in all tissues, every tissue showed characteristically abundant metabolites which could be rationalised against specific tissue functions. For example, the cuticle contained high levels of glutathione, reflecting a role in oxidative defence; the alimentary canal (like vertebrate gut) had high levels of acylcarnitines for fatty acid metabolism, and the head contained high levels of ether lipids. The male accessory gland uniquely contained decarboxylated S-adenosylmethionine. These data thus both provide valuable insights into tissue function, and a reference baseline, compatible with the FlyAtlas.org transcriptomic resource, for further metabolomic analysis of this important model organism, for example in the modelling of human inborn errors of metabolism, aging or metabolic imbalances such as diabetes
Distractor Inhibition Predicts Individual Differences in the Attentional Blink
Background: The attentional blink (AB) refers to humans' impaired ability to detect the second of two targets (T2) in a rapid serial visual presentation (RSVP) stream of distractors if it appears within 200-600 ms of the first target (T1). Here we examined whether humans' ability to inhibit distractors in the RSVP stream is a key determinant of individual differences in T1 performance and AB magnitude
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