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1.
J Dairy Sci ; 104(1): 1087-1098, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33189280

ABSTRACT

Cervicovaginal mucus is a mixture of mucins, ions, salts, and water, the proportions of which change during the reproductive cycle. It is suspected that this mucus emits an important volatile signal indicative of the reproductive state of the female. The objective of this study was to identify volatile organic compounds (VOC) in bovine cervicovaginal mucus that are modulated during the estrous cycle and could potentially be used as biomarkers of estrus and ovulation. Cervicovaginal mucus was collected from crossbred beef heifers (n = 8), which were synchronized using an 8-d controlled internal drug release (CIDR) protocol and in which onset of estrus and time of ovulation were determined by visual observation and ultrasonography, respectively. Mucus samples were collected between 0 and 96 h after CIDR removal (estrus onset occurred at 49.1 ± 3.3 h after CIDR removal). A validation study was performed on an independent group of 15 heifers from which cervicovaginal mucus samples were collected every 8 h from 40 to 80 h after CIDR removal. The VOC in mucus were identified using gas chromatography-mass spectrometry and selected compounds were quantified using selected-ion flow-tube mass spectrometry. The presence of 47 VOC was detected in mucus samples by gas chromatography-mass spectrometry with those exhibiting highest abundance including 2-butanone, acetone, 2-pentanone, 4-methyl-2-pentanone, 1-(1-methylethoxy)-2-propanone, ethanol, 2-methyl-2-propanol, and 2-butanol. All VOC peaked between 24 to 47 h after the onset of estrus (ovulation occurred 26.6 ± 5.6 h after estrus onset). Two VOC, 2-pentanone and 4-methyl-2-pentanone, exhibited a significant increase at the onset of estrus, whereas concentration of 2-butanone increased significantly just after estrus onset, indicating that these VOC may be used as putative biomarkers of estrus. The results of our study may contribute to the development of a sensor device based on VOC to aid the detection of estrus and ovulation in cattle, with particular relevance for the dairy industry where the majority of females are bred by artificial insemination.


Subject(s)
Cattle/metabolism , Cervix Mucus/metabolism , Estrus Synchronization , Estrus , Ovulation/metabolism , Vagina/microbiology , Volatile Organic Compounds/metabolism , Animals , Delayed-Action Preparations , Estrus Synchronization/methods , Female , Insemination, Artificial/veterinary , Predictive Value of Tests , Progesterone , Ultrasonography/veterinary
2.
J Exp Psychol Gen ; 148(7): 1138-1152, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31219287

ABSTRACT

It is often unclear which course of action gives the best outcome. We can reduce this uncertainty by gathering more information, but gathering information always comes at a cost. For example, a sports player waiting too long to judge a ball's trajectory will run out of time to intercept it. Efficient samplers must therefore optimize a trade-off: when the costs of collecting further information exceed the expected benefits, they should stop sampling and start acting. In visually guided tasks, adults can make these trade-offs efficiently, correctly balancing any reductions in visuomotor uncertainty against cost factors associated with increased sampling. To investigate how this ability develops during childhood, we tested 6- to 11-year-olds, adolescents, and adults on a visual localization task in which the costs and benefits of sampling were formalized in a quantitative framework. This allowed us to compare participants to each other and to an ideal observer who maximizes expected reward. Visual sampling became substantially more efficient between 6 and 11 years, converging onto adult performance in adolescence. Younger children systematically undersampled information relative to the ideal observer and varied their sampling strategy more. Further analyses suggested that young children used a suboptimal decision rule that insufficiently accounted for the chance of task failure, in line with a late developing ability to compute with probabilities and costs. We therefore propose that late development of efficient information sampling, a crucial element of real-world decision-making under risk, may form an important component of suboptimality in child perception, action, and decision-making. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Subject(s)
Adolescent Development/physiology , Child Development/physiology , Decision Making/physiology , Visual Perception/physiology , Adolescent , Adult , Child , Female , Humans , Male , Probability , Reward
3.
Child Dev ; 86(5): 1449-57, 2015.
Article in English | MEDLINE | ID: mdl-26228618

ABSTRACT

To reduce sensory uncertainty, humans combine cues from multiple senses. However, in everyday life, many co-occurring cues are irrelevant to the task at hand. How do humans know which cues to ignore? And does this ability change with development? This study shows the ability to ignore cross-modal irrelevant information develops late in childhood. Participants performed a sound discrimination task, with or without an irrelevant visual flash, presented synchronously in front of them. Adults ignored the irrelevant visual information, while 7- to 10-year-olds' responses were biased toward the flash location. The findings show that acquiring mature cue combination mechanisms is a multifaceted process that includes learning to ignore irrelevant cues, as well as to optimally combine relevant cues.


Subject(s)
Child Development/physiology , Cues , Psychomotor Performance/physiology , Sound Localization/physiology , Visual Perception/physiology , Adult , Child , Female , Humans , Male , Young Adult
4.
Mycol Res ; 108(Pt 7): 806-14, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15446714

ABSTRACT

Volatile organic compounds (VOCs) emitted by two wood-rotting basidiomycete fungi, Serpula lacrymans (dry rot fungus) and Coniophora puteana (cellar fungus), and the timber of Pinus sylvestris (Scots pine), were identified. Several volatile collection techniques were employed including dichloromethane solvent extraction, solid-phase microextraction (SPME) and thermal desorption of VOCs entrained on Tenax GR. In addition, a new method of solid sample injection (SSI) is described which utilises a low injector temperature and an all-glass deactivated injector liner designed to minimise both the formation of pyrolysis products and analyte degradation. All the volatile compounds collected were analysed using electron impact capillary gas chromatography-mass spectrometry (GC-MS) on HP-5, HP-Innowax and beta-cyclodextrin columns. SSI and Tenax thermal desorption were found to be the most effective extraction methods. A total of 19 VOCs were observed from S. lacrymans grown on glass slides and pine, 15 from C. puteana grown on glass slides and 12 from P. sylvestris timber. S. lacrymans was found to emit, in low abundance, six unique VOCs, of which 2-methylbutanal was the greatest. The major volatile compound emitted by S. lacrymans was 1-octen-3-ol, which was also found in lower abundance from C. puteana. Six VOCs, including diethylene glycol and 4-methyl methylbenzoate, were found to be unique to C. puteana, all in medium abundance: From P. sylvestris, the major volatiles identified were S-alpha-pinene and 3-carene.


Subject(s)
Basidiomycota/chemistry , Pinus sylvestris/microbiology , Gas Chromatography-Mass Spectrometry , Organic Chemicals/isolation & purification , Volatilization
5.
Spine (Phila Pa 1976) ; 28(2): 171-6, 2003 Jan 15.
Article in English | MEDLINE | ID: mdl-12544935

ABSTRACT

STUDY DESIGN: A retrospective clinical observational study was conducted. OBJECTIVE: To assess the relation of spinal fracture type and its magnitude of distortion to subsequent long-term development of late spinal deformity in childhood onset spinal cord injury. SUMMARY OF BACKGROUND DATA: In this study, 76 adults who sustained spinal cord injury during childhood were examined clinically and radiographically alongside a retrospective review of case notes and radiographs. METHODS: The nature of the spinal injury and the progression of its displacement were defined from radiographs taken immediately after injury, then at 4 months and at 1 year. Eventual adult spinal deformity was defined from standardized erect long-plate radiographs. Scoliosis, kyphosis, and lordosis were measured using Cobb's method. RESULTS: There was no statistically significant difference in the severity of scoliosis, kyphosis, or lordosis between traumatic and nontraumatic injuries, nor between patients with and those without radiologically visible bony injury. Of the 14 patients with traumatic thoracic and lumbar injuries who had undergone no surgical intervention, 10 (71%) showed development of major scoliotic curves that did not include the fracture site. The patients with no angular displacement at the fracture site after 1 year went on to experience the development of more severe scoliosis (mean, 66 degrees) than those who had displaced fractures (mean, 38 degrees). In five, a low kyphotic curve and a compensatory lordosis above it developed. CONCLUSIONS: There is no evidence that the bony injury to the vertebral column itself in the child with spinal cord injury influences the development of late scoliosis or lordosis, but it may influence any eventual kyphosis.


Subject(s)
Lumbar Vertebrae/diagnostic imaging , Spinal Fractures/classification , Spinal Fractures/diagnostic imaging , Thoracic Vertebrae/diagnostic imaging , Adolescent , Adult , Cohort Studies , Disease Progression , Female , Humans , Kyphosis/complications , Kyphosis/diagnostic imaging , Kyphosis/etiology , Lordosis/complications , Lordosis/diagnostic imaging , Lordosis/etiology , Male , Middle Aged , Radiography , Retrospective Studies , Scoliosis/complications , Scoliosis/diagnostic imaging , Scoliosis/etiology , Spinal Cord Injuries/complications , Spinal Fractures/complications
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