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1.
Chem Commun (Camb) ; 60(20): 2800-2803, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38362749

ABSTRACT

Quasiracemic materials constructed with two points of structural difference were used to understand the role molecular shape plays in molecular assembly. Hot stage, crystallographic and occupied cavity space assessments provide insight into how imposed CH3/Cl and H/CF3 structural variations placed on benzoyl leucine and phenylalanine scaffolds result in a remarkably high occurrence of cocrystal formation.

2.
Top Cogn Sci ; 2023 Apr 13.
Article in English | MEDLINE | ID: mdl-37052261

ABSTRACT

Artificial social intelligence (ASI) agents have great potential to aid the success of individuals, human-human teams, and human-artificial intelligence teams. To develop helpful ASI agents, we created an urban search and rescue task environment in Minecraft to evaluate ASI agents' ability to infer participants' knowledge training conditions and predict participants' next victim type to be rescued. We evaluated ASI agents' capabilities in three ways: (a) comparison to ground truth-the actual knowledge training condition and participant actions; (b) comparison among different ASI agents; and (c) comparison to a human observer criterion, whose accuracy served as a reference point. The human observers and the ASI agents used video data and timestamped event messages from the testbed, respectively, to make inferences about the same participants and topic (knowledge training condition) and the same instances of participant actions (rescue of victims). Overall, ASI agents performed better than human observers in inferring knowledge training conditions and predicting actions. Refining the human criterion can guide the design and evaluation of ASI agents for complex task environments and team composition.

3.
Hum Factors ; : 187208231162449, 2023 Mar 22.
Article in English | MEDLINE | ID: mdl-36946439

ABSTRACT

OBJECTIVE: We review the current state-of-the-art in team cognition research, but more importantly describe the limitations of existing theories, laboratory paradigms, and measures considering the increasing complexities of modern teams and the study of team cognition. BACKGROUND: Research on, and applications of, team cognition has led to theories, data, and measures over the last several decades. METHOD: This article is based on research questions generated in a spring 2022 seminar on team cognition at Arizona State University led by the first author. RESULTS: Future research directions are proposed for extending the conceptualization of teams and team cognition by examining dimensions of teamness; extending laboratory paradigms to attain more realistic teaming, including nonhuman teammates; and advancing measures of team cognition in a direction such that data can be collected unobtrusively, in real time, and automatically. CONCLUSION: The future of team cognition is one of the new discoveries, new research paradigms, and new measures. APPLICATION: Extending the concepts of teams and team cognition can also extend the potential applications of these concepts.

4.
Mar Pollut Bull ; 183: 114086, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36108527

ABSTRACT

Anthropogenic sedimentation is a major contributor to the worldwide decline in coral cover. Resuspension of benthic material can exacerbate the threat to corals, but evidence of vertical sediment gradients is limited. Here, we installed sediment traps at 10, 20, 30, 40, and 50 cm above the substrate at three equatorial reef sites for three months and determined the dry mass, particle size, and biogeochemical composition of the material collected. As the trap mouth height increased from 10 to 50 cm, dry mass decreased as sediments became finer, poorer in carbonate, and richer in silicate. Despite among-site differences in collected sediment, this vertical gradient was present in all trap arrays, likely driven by resuspension mechanisms on seabed sediments. These results have implications for coral vertical ecology and underline the importance of standardising sediment collection protocols.


Subject(s)
Anthozoa , Coral Reefs , Animals , Carbonates , Geologic Sediments , Particle Size , Silicates
5.
Adv Mar Biol ; 87(1): 115-140, 2020.
Article in English | MEDLINE | ID: mdl-33293008

ABSTRACT

The reefs of Singapore provide an excellent opportunity to study the population dynamics and growth rates of free-living mushroom corals (Fungiidae) under sediment-stressed conditions. Transect surveys at four study sites revealed a total of 11 free-living mushroom coral species-the same 11 species as those found by local studies since the 1980s. The abundance of the four most common species ranged from 1.0 to 68.3 Ind. per 100m2, while their population size-structure showed a common pattern of a higher proportion of small-sized corals than large-sized ones (i.e. positively skewed size-structure), although very few individuals of the smallest-size classes were recorded for any of the four species. A more positively skewed size-structure for each of the four most common species was observed at the reef slope (5-6m depth) than at the reef crest (2-3m depth), possibly due to a slower growth rate caused by light reduction with depth. All the mushroom corals studied exhibited a decline in growth rate with increasing size and weight, indicating determinate growth. Growth rate of each of the four most common species was similar among the study sites, despite variation in environmental conditions. Our results demonstrate species richness stability over the past three decades, suggesting that these free-living mushroom coral assemblages comprise species that are well-adapted to the chronic high sedimentation characteristic of Singapore's reefs. However, if the paucity of individuals of the smallest-size classes reflects poor recruitment and/or early mortality, there may be some cause for concern. Our robust baseline data can contribute to a long-term monitoring strategy for determination of changes in mushroom coral population dynamics.


Subject(s)
Anthozoa/physiology , Coral Reefs , Adaptation, Physiological , Animals , Population Dynamics , Singapore , Stress, Physiological
6.
Mar Pollut Bull ; 151: 110890, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32056657

ABSTRACT

Global declines in live coral cover and the proliferation of macroalgae on coral reefs is leading to increased coral-macroalgal interactions that impact reef recovery. However, the effects of macroalgae on coral sexual reproduction-a fundamental life-history process for maintaining population abundances-have rarely been quantified. Here, we examined the direct effects of macroalgae contact on the fecundity (eggs mesentery-1) of two coral species, Echinopora lamellosa and Merulina ampliata, across three degraded reefs in Singapore. Increasing macroalgae contact from 5% to 25% significantly reduced fecundity in colonies of both species by 67-82%, and also reduced M. ampliata egg sizes by 11.4%. These results suggest the diversion of energy from reproduction towards other processes such as repair and defence, and also reveal potential differential energy allocation strategies among coral taxa. While corals on Singapore's impacted reefs continue to produce eggs, increasing macroalgae that suppresses coral fecundity may constrain future reef recovery.


Subject(s)
Anthozoa , Coral Reefs , Seaweed , Animals , Fertility , Singapore
7.
Transl Vis Sci Technol ; 8(4): 7, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31360613

ABSTRACT

PURPOSE: Lack of outdoor time is a known risk factor for myopia. Knowledge of the light levels reaching the eye and exposure settings, including sun-protective measures, is essential for outdoor programs and myopia. We evaluated the impact of sun-protective strategies (hat and sunglasses) on maintaining high illuminance levels to prevent myopia. METHODS: A child-sized mannequin head was developed to measure light illuminance levels with and without sun-protective equipment, across a wide range of environments in Singapore, outdoors (open park, under a tree, street) and indoors (under a fluorescent illumination with window, under white LED-based lighting without window). A comparison was made between indoor and outdoor light levels that are experienced while children are involved in day-to-day activities. RESULTS: Outdoor light levels were much higher (11,080-18,176 lux) than indoors (112-156 lux). The higher lux levels protective of myopia (>1000 lux) were measured at the tree shade (5556-7876 lux) and with hat (4112-8156 lux). Sunglasses showed lux levels between 1792 and 6800 lux. Although with sunglasses readings were lower than tree shade and hat, light levels were still 11 to 43 times higher than indoors. CONCLUSIONS: Recommendations on spending time outdoors for myopia prevention with adequate sun protection should be provided while partaking in outdoor activities, including protection under shaded areas, wearing a hat or sunglasses, sunscreen, and adequate hydration. TRANSLATIONAL RELEVANCE: Light levels outdoors were higher than indoors and above the threshold illuminance for myopia prevention even with adequate sun-protective measures.

8.
PeerJ ; 4: e2180, 2016.
Article in English | MEDLINE | ID: mdl-27478697

ABSTRACT

Most studies of coral reproductive biology to date have focused on oocyte numbers and sizes. Only one (ex situ) study has enumerated sperm numbers, even though these data have multiple potential applications. We quantified total coral sperm and eggs per gamete bundle collected from six species in situ during a synchronous spawning event in Singapore. Egg-sperm bundles were captured midwater as they floated towards the surface after being released by the colony. For each sample, a semi-transparent soft plastic bottle was squeezed and released to create a small suction force that was used to 'catch' the bundles. This technique provided several advantages over traditional methods, including low cost, ease of use, no diving prior to the night of collection needed, and the ability to target specific areas of the colony. The six species sampled were Echinophyllia aspera, Favites abdita, F. chinensis, Merulina ampliata, M. scabricula and Platygyra pini. The mean number of sperm packaged within one egg-sperm bundle ranged from 2.04 × 10(6) to 1.93 × 10(7). The mean number of eggs per egg-sperm bundle ranged from 26.67 (SE ± 3.27) to 85.33 (SE ± 17.79). These data are critical for fertilisation success models, but the collection technique described could also be applied to studies requiring in situ spawning data at the polyp level.

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