5,436 research outputs found
Action-monitoring and Intention Reporting in Children with Autism
The āmindblindnessā theory of core cognitive impairment in autism and at least one of the executive theories of the core cognitive deficit both predict that children with autism should find it difficult to report what their intention was when it diverged from an outcome. The former predicts this because it takes intention reporting to require a ātheory of mindā and the latter predicts it because the theory posits an impairment in the monitoring of goal-directed actions. The latter also predicts impairments in the ability to monitor basic actions. Our three studies failed to support either of these views. Experiment 1 demonstrated intact abilities in the monitoring of basic actions (detecting which stimulus of a number of stimuli one is controlling). Experiment 2 demonstrated intact abilities in reporting an intention, both for self and for another agent, when the outcome was unintended but desired. In Experiment 3, using the novel ātransparent intentions taskā, we found (with a minor qualification) intact ability in reporting on nonballistic intended actions when the result that the action achieved was unexpected. The implications of these results for views of the relation between theory of mind and executive difficulties in autism are discussed
Cell fate patterning during C. elegans vulval development
Precursor cells of the vulva of the C. elegans hermaphrodite choose between two vulval cell fates (1Ā° and 2Ā°) and a non-vulval epidermal fate (3Ā°) in response to three intercellular signals. An inductive signal produced by the anchor cell induces the vulval precursors to assume the 1Ā° and 2Ā° vulval fates. This inductive signal is an EGF-like growth factor encoded by the gene lin-3. An inhibitory signal mediated by lin-15, and which may originate from the surrounding epidermis, prevents the vulval precursors from assuming vulval fates in the absence of the inductive signal. A short range lateral signal, which acts through the gene lin-12, regulates the pattern of 1Ā° and 2Ā° fates assumed by the induced vulval precursors.
The combined action of the three signals precisely directs the six vulval precursors to adopt a 3Ā° 3Ā° 2Ā° 1Ā° 2 Ā° 3Ā° pattern of fates. The amount of inductive signal produced by the anchor cell appears to determine the number or vulval precursors that assume vulval fates. The three induced vulval precursors most proximal to the anchor cell are proposed to adopt the 2Ā° 1Ā° 2Ā° pattern of fates in response to a gradient of the inductive signal and also in response to lateral signalling that inhibits adjacent vulval precursor cells from both assuming the 1Ā° fate
Field Guarding as a Crop Protection Method: Preliminary Implications for Improving Field Guarding
Negative interactions between crop farmers and wild primates are an issue of significant concern. Despite many crop farmers using field guards as a method of crop protection against foraging primates, there are very few published accounts of how effective this technique is and how it might be improved. To bridge this knowledge gap, we used direct observations from a hide to collect the behaviors of field guards, chacma baboons (Papio ursinus; baboons), and vervet monkeys (Chlorocebus pygerythrus; vervets) foraging in a 1-ha butternut squash (Cucurbita moschata) field for 4 months (May to August) in 2013 on a 564-ha commercial farm in the Blouberg District of South Africa. Only half of the crop-foraging events were chased by field guards, with vervets being chased much less frequently than baboons. Guards responded more often to events with greater primate numbers and to those that occurred earlier in the day. Guard delay in responding to crop-foraging events and baboon delay in responding to the guard both increased in the low productivity season. Baboon response delay also increased with more animals involved. Based on this case study, we suggest recommendations to improve the effectiveness of field guarding. This includes implementing an early warning alarm system, shortening field guard shifts, increasing guard numbers during the morning and low productivity season, and increasing the perceived fear of field guards, potentially by employing male guards or providing uniforms and deterrent accessories. Further evaluation in other local contexts will help determine how these findings can be adopted on a wider scale
Baboon and Vervet Monkey Crop-Foraging Behaviors on a Commercial South African Farm: Preliminary Implications for Damage Mitigation
Conflict between crop farmers and wild nonhuman primates is a worldwide conservation issue of increasing concern. Most of the research on wild primate crop foraging has so far focused on the conflicts with subsistence agriculture. Crop damage caused by primate foraging in large-scale commercial agriculture is also a major facet of humanāwildlife conflict. Despite its increasing severity, there are very few published accounts of on-farm wild primate crop-foraging behavior or effective techniques to deter primates from field crops on commercial farms. To address this knowledge gap and identify some mitigation strategies, we used direct observation from a hide to collect behaviors and interspecific interactions between chacma baboons (Papio ursinus; baboons) and vervet monkeys (Chlorocebus pygerythrus; vervets) foraging in a 1-ha butternut squash (Cucurbita moschata) field for 4 months (May to August) in 2013 on a 564-ha commercial farm in the Blouberg District of South Africa. Baboons caused the most crop damage, foraged on crops more in the mornings, and their rates of crop foraging were influenced primarily by natural vegetation productivity. Vervet monkey rates of crop foraging were primarily influenced by the presence of baboons. When baboons or vervets visited the farm, half of the visits did not involve crop foraging, and vervets were more likely to crop forage when they visited than baboons. Based on this preliminary study, we make recommendations for crop farmers to improve the effectiveness of current deterrent methods. These include increasing deterrent efforts when natural vegetation drops below a normalized difference vegetation index value of 0.32, especially during the hours before midday, chasing baboons and vervets farther from the farm rather than just out of crop fields, and increasing the perceived mortality risk of field guards. These recommendations should be evaluated to determine effectiveness before being adopted on a wider scale
What Do Executive Factors Contribute to the Failure on False Belief Tasks by Children with Autism?
As children with autism have pervasive executive difficulties it is necessary to determine
whether these contribute to their often-reported failure on the false belief task. Failure on
this task is frequently taken to diagnose the lack of a ``theory of mind''. We report two
studies using two tasks that make similar executive demands to the false belief task. The first
experiment showed that children with autism are significantly challenged by a "conflicting
desire" task, which suggests that their difficulty with the false belief task is not rooted in
difficulty with grasping the representational nature of belief. In the second study children
with autism were also found to be impaired on a novel version of the "false photograph
task". A parsimonious reading of these data is that their difficulty with all three tasks is due
to commonalities in the tasks' executive structure
Insights into shortā and longāterm cropāforaging strategies in a chacma baboon (Papio ursinus) from GPS and accelerometer data
Cropāforaging by animals is a leading cause of humanāwildlife āconflictā globally, affecting farmers and resulting in the death of many animals in retaliation, including primates. Despite significant research into cropāforaging by primates, relatively little is understood about the behavior and movements of primates in and around crop fields, largely due to the limitations of traditional observational methods. Cropāforaging by primates in largeāscale agriculture has also received little attention. We used GPS and accelerometer bioāloggers, along with environmental data, to gain an understanding of the spatial and temporal patterns of activity for a female in a cropāforaging baboon group in and around commercial farms in South Africa over one year. Crop fields were avoided for most of the year, suggesting that fields are perceived as a highārisk habitat. When field visits did occur, this was generally when plant primary productivity was low, suggesting that crops were a āfallback foodā. All recorded field visits were at or before 15:00. Activity was significantly higher in crop fields than in the landscape in general, evidence that cropāforaging is an energetically costly strategy and that fields are perceived as a risky habitat. In contrast, activity was significantly lower within 100 m of the field edge than in the rest of the landscape, suggesting that baboons wait near the field edge to assess risks before cropāforaging. Together, this understanding of the spatiotemporal dynamics of cropāforaging can help to inform crop protection strategies and reduce conflict between humans and baboons in South Africa
On-primate cameras reveal undocumented foraging behaviour and interspecies interactions in chacma baboons (Papio ursinus)
Historically, direct observation by human observers has been the primary method for studying primate behaviour. However, human observation may alter the behaviour of even habituated primates and that of other animals in their environment (LaBarge et al., 2020). Observers may miss rare or subtle behaviours, particularly if maintaining recommended observation distances (Moll et al., 2007). Remote methods, including on-animal cameras, can overcome some of these limitations.Cameras have been deployed on a range of animals to study behaviour, although primarily on larger-bodied species. However, the use of cameras on primates has been limited (Fuentes et al., 2014). Yet on-animal cameras have the potential to reveal important aspects of primate behaviour from a āprimate-eye perspectiveā, with cameras collecting data continuously, close-up, and at high resolution. The method thus has the potential to give exciting and novel insights into primate behaviour.We deployed custom-made, high-resolution, primate-borne video cameras on chacma baboons (Papio ursinus) in South Africa to gain insights into their behaviour and foraging in an agricultural landscape and to illustrate the potential advantages of this method, with a focus on undocumented foraging behaviours and interspecific interactions. Chacma baboons are omnivorous and occasionally prey on small antelope. Their flexible diets also may incorporate alternative anthropogenic food resources from agricultural areas (Walton et al., 2021). Although previously studied by using bio-loggers (Walton et al., 2021), these were without integrated video recording
Colloidal stabilization via nanoparticle haloing
We present a detailed numerical study of effective interactions between
micron-sized silica spheres, induced by highly charged zirconia nanoparticles.
It is demonstrated that the effective interactions are consistent with a
recently discovered mechanism for colloidal stabilization. In accordance with
the experimental observations, small nanoparticle concentrations induce an
effective repulsion that counteracts the intrinsic van der Waals attraction
between the colloids and thus stabilizes the suspension. At higher nanoparticle
concentrations an attractive potential is recovered, resulting in reentrant
gelation. Monte Carlo simulations of this highly size-asymmetric mixture are
made possible by means of a geometric cluster Monte Carlo algorithm. A
comparison is made to results obtained from the Ornstein-Zernike equations with
the hypernetted-chain closure
RESPOND ā A patient-centred program to prevent secondary falls in older people presenting to the emergency department with a fall: Protocol for a multi-centre randomised controlled trial
Introduction: Participation in falls prevention activities by older people following presentation to the Emergency Department (ED) with a fall is suboptimal. This randomised controlled trial (RCT) will test the RESPOND program which is designed to improve older personsā participation in falls prevention activities through delivery of patient-centred education and behaviour change strategies. Design and setting: An RCT at two tertiary referral EDs in Melbourne and Perth, Australia. Participants: Five-hundred and twenty eight community-dwelling people aged 60-90 years presenting to the ED with a fall and discharged home will be recruited. People who: require an interpreter or hands-on assistance to walk; live in residential aged care or >50 kilometres from the trial hospital; have terminal illness, cognitive impairment, documented aggressive behaviour or history of psychosis; are receiving palliative care; or are unable to use a telephone will be excluded. Methods: Participants will be randomly allocated to the RESPOND intervention or standard care control group. RESPOND incorporates: (1) home-based risk factor assessment; (2) education, coaching, goal setting, and follow-up telephone support for management of one or more of four risk factors with evidence of effective intervention; and (3) healthcare provider communication and community linkage delivered over six months. Primary outcomes are falls and fall injuries per-person-year. Discussion: RESPOND builds on prior falls prevention learnings and aims to help individuals make guided decisions about how they will manage their falls risk. Patient-centred models have been successfully trialled in chronic and cardiovascular disease however evidence to support this approach in falls prevention is limited. Trial registration. The protocol for this study is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12614000336684)
The Feasibility of a Using a Smart Button Mobile Health System to Self-Track Medication Adherence and Deliver Tailored Short Message Service Text Message Feedback
BACKGROUND:
As many as 50% of people experience medication nonadherence, yet studies for detecting nonadherence and delivering real-time interventions to improve adherence are lacking. Mobile health (mHealth) technologies show promise to track and support medication adherence.
OBJECTIVE:
The study aimed to evaluate the feasibility and acceptability of using an mHealth system for medication adherence tracking and intervention delivery. The mHealth system comprises a smart button device to self-track medication taking, a companion smartphone app, a computer algorithm used to determine adherence and then deliver a standard or tailored SMS (short message service) text message on the basis of timing of medication taking. Standard SMS text messages indicated that the smartphone app registered the button press, whereas tailored SMS text messages encouraged habit formation and systems thinking on the basis of the timing the medications were taken.
METHODS:
A convenience sample of 5 adults with chronic kidney disease (CKD), who were prescribed antihypertensive medication, participated in a 52-day longitudinal study. The study was conducted in 3 phases, with a standard SMS text message sent in phases 1 (study days 1-14) and 3 (study days 46-52) and tailored SMS text messages sent during phase 2 (study days 15-45) in response to participant medication self-tracking. Medication adherence was measured using: (1) the smart button and (2) electronic medication monitoring caps. Concordance between these 2 methods was evaluated using percentage of measurements made on the same day and occurring within Ā±5 min of one another. Acceptability was evaluated using qualitative feedback from participants.
RESULTS:
A total of 5 patients with CKD, stages 1-4, were enrolled in the study, with the majority being men (60%), white (80%), and Hispanic/Latino (40%) of middle age (52.6 years, SD 22.49; range 20-70). The mHealth system was successfully initiated in the clinic setting for all enrolled participants. Of the expected 260 data points, 36.5% (n=95) were recorded with the smart button and 76.2% (n=198) with electronic monitoring. Concordant events (n=94), in which events were recorded with both the smart button and electronic monitoring, occurred 47% of the time and 58% of these events occurred within Ā±5 min of one another. Participant comments suggested SMS text messages were encouraging.
CONCLUSIONS:
It was feasible to recruit participants in the clinic setting for an mHealth study, and our system was successfully initiated for all enrolled participants. The smart button is an innovative way to self-report adherence data, including date and timing of medication taking, which were not previously available from measures that rely on recall of adherence. Although the selected smart button had poor concordance with electronic monitoring caps, participants were willing to use it to self-track medication adherence, and they found the mHealth system acceptable to use in most cases
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