Partner gaze shapes the relationship between symptoms of psychopathology and interpersonal coordination.

Interpersonal coordination is a key determinant of successful social interaction but can be disrupted when people experience symptoms related to social anxiety or autism. Effective coordination rests on individuals directing their attention towards interaction partners. Yet little is known about the impact of the attentional behaviours of the partner themselves. As the gaze of others has heightened salience for those experiencing social anxiety or autism, addressing this gap can provide insight into how symptoms of these disorders impact coordination. Using a novel virtual reality task, we investigated whether partner gaze (i.e., direct vs. averted) influenced the emergence of interpersonal coordination. Results revealed: (i) spontaneous coordination was diminished in the averted (cf. direct) gaze condition; (ii) spontaneous coordination was positively related to symptoms of social anxiety, but only when partner gaze was averted. This latter finding contrasts the extant literature and points to the importance of social context in shaping the relationship between symptoms of psychopathology and interpersonal coordination.

α-Synuclein Aggregates Increase the Conductance of Substantia Nigra Dopamine Neurons, an Effect Partly Reversed by the KATP Channel Inhibitor Glibenclamide.

Dopaminergic neurons (DNs) in the substantia nigra pars compacta (SNpc) form an important part of the basal ganglia circuitry, playing key roles in movement initiation and coordination. A hallmark of Parkinson's disease (PD) is the degeneration of these SNpc DNs leading to akinesia, bradykinesia and tremor. There is gathering evidence that oligomeric α-synuclein (α-syn) is one of the major pathologic species in PD, with its deposition in Lewy bodies (LBs) closely correlated with disease progression. However, the precise mechanisms underlying the effects of oligomeric α-syn on DN function have yet to be fully defined. Here, we have combined electrophysiological recording and detailed analysis to characterize the time-dependent effects of α-syn aggregates (consisting of oligomers and possibly small fibrils) on the properties of SNpc DNs. The introduction of α-syn aggregates into single DNs via the patch electrode significantly reduced both the input resistance and the firing rate without changing the membrane potential. These effects occurred after 8-16 min of dialysis but did not occur with the monomeric form of α-syn. The effects of α-syn aggregates could be significantly reduced by preincubation with the ATP-sensitive K+ channel (KATP) inhibitor glibenclamide. These data suggest that accumulation of α-syn aggregates in DNs may chronically activate KATP channels leading to a significant loss of excitability and dopamine release.

From Crowdsourcing to Extreme Citizen Science: Participatory Research for Environmental Health.

Environmental health issues are becoming more challenging, and addressing them requires new approaches to research design and decision-making processes. Participatory research approaches, in which researchers and communities are involved in all aspects of a research study, can improve study outcomes and foster greater data accessibility and utility as well as increase public transparency. Here we review varied concepts of participatory research, describe how it complements and overlaps with community engagement and environmental justice, examine its intersection with emerging environmental sensor technologies, and discuss the strengths and limitations of participatory research. Although participatory research includes methodological challenges, such as biases in data collection and data quality, it has been found to increase the relevance of research questions, result in better knowledge production, and impact health policies. Improved research partnerships among government agencies, academia, and communities can increase scientific rigor, build community capacity, and produce sustainable outcomes.

Components of Population Vulnerability and Their Relationship With Climate-Sensitive Health Threats.

Climate change is increasingly being framed as risks that will impact the poorest and most vulnerable communities among us. This has led to more efforts to estimate climate change risks across populations and in the context of human health and health equity. We describe the public health dimensions of climate vulnerability-exposure, population sensitivity, and adaptive capacity-and explore how these dimensions can modify population health impacts and their distribution. An overview of health disparities associated with specific climate risks is presented, and we offer potential solutions grounded in equitable urban development and improved characterization of climate vulnerabilities.

Order parameter dynamics of body-scaled hysteresis and mode transitions in grasping behavior.

Several experimental studies have shown that human grasping behavior exhibits a transition from one-handed to two-handed grasping when to-be-grasped objects become larger and larger. The transition point depends on the relative size of objects measured in terms of human body-scales. Most strikingly, the transitions between the two different behavioral 'modes' of grasping exhibit hysteresis. That is, one-to-two hand transitions and two-to-one hand transitions occur at different relative object sizes when objects are scaled up or down in size. In our study we approach body-scaled hysteresis and mode transitions in grasping by exploiting the notion that human behavior in general results from self-organization and satisfies appropriately-defined order parameter equations. To this end, grasping transitions and grasping hysteresis are discussed from a theoretical perspective in analogy to cognitive processes defined by Haken's neural network model for pattern recognition. In doing so, issues such as the exclusivity of grasping modes, biomechanical constraints, mode-mode interactions, single subject behavior and population behavior are explored.

Velocity and curvature in human locomotion along complex curved paths: a comparison with hand movements.

There is extensive experimental evidence linking instantaneous velocity to curvature in drawing and hand-writing movements. The empirical relationship between these characteristics of motion and path is well described by a power law in which the velocity varies in proportion to the one-third power of the radius of curvature. It was recently shown that a similar relationship can be observed during locomotion along curved elliptical paths raising the possibility that these very different motor activities might, at some level, share the same planning strategies. It has, however, been noted that the ellipse is a special case with respect to the one-third power law and therefore these previous results might not provide strong evidence that the one-third power law is a general feature of locomotion around curved paths. For this reason the experimental study of locomotion and its comparison with hand writing is extended here to non-elliptical paths. Subjects walked along predefined curved paths consisting of two complex shapes drawn on the ground: the cloverleaf and the limacon. It was found that the data always supported a close relationship between instantaneous velocity and curvature. For these more complex paths, however, the relationship is shape-dependent--although velocity and curvature can still be linked by a power law, the exponent depends on the geometrical form of the path. The results demonstrate the existence of a close relationship between instantaneous velocity and curvature in locomotion that is more general than the one-third power law. The origins of this relationship and its possible explanation in the mechanical balance of forces and in central planning are discussed.

Boundary effects in reaction-diffusion processes.

The effects of a boundary on reaction systems are examined in the framework of the general single-species reaction/coalescence process. The boundary naturally represents the reactants' container, but is applicable to exciton dynamics in a doped TMMC crystal. We show that a density excess, which extends into the system diffusively from the boundary, is formed in two dimensions and below. This implies a surprising result for the magnetization near a fixed spin in the coarsening of the one-dimensional critical Ising model. The universal, dimensionally dependent functional forms of this density excess are given by an exact solution and the field-theoretic renormalization group.

Giant cell tumor of bone.

Giant cell tumor of bone is an unusual neoplasm and treatment commonly leads to local recurrence. This can be related to the aggressiveness of the tumor or to the incompleteness of its removal. This study includes 27 cases that presented to our institution between the 1984 and 1994. One case was as a consultation only and 9 cases, either Campanacci Grade 3 or patients with considerable joint destruction, were treated by resection and reconstruction. One case was treated by curettage and cementation. Sixteen cases were treated with a combination of radical curettage, high speed burring, pulsatile lavage, and bone graft (either autograft or allograft mixed with autograft). No other adjuvant therapy was used. All of these 16 cases had a minimum follow-up of 5 years and none had a local recurrence. This study demonstrates that local control of giant cell tumors can be obtained by appropriate staging, resection of aggressive tumors, and by conservative management of the others. Such conservative management provides a bony matrix for the subchondral bone that is preferable to other treatments that have become popular in recent years, including cementation. This should provide better joint function in the longer term. High local recurrence rates have been reported in other series, but by a combination of appropriate selection of cases and by careful treatment of the Campanacci Grade 1 and 2 cases, these patients can have an uncomplicated outcome.

Effects of narcotic and non-narcotic continuous epidural anesthesia on intrapartum fetal heart rate tracings as measured by computer analysis.

OBJECTIVE: To evaluate the effect of narcotic and non-narcotic continuous epidural anesthesia on intrapartum fetal heart rate (FHR) tracings as measured by computer analysis. METHODS: We studied 37 women with uncomplicated pregnancies at term with reactive FHR tracings. The women were randomized to receive epidural anesthesia with either bupivicaine with fentanyl or bupivicaine alone. One-hour FHR tracings were obtained before epidural anesthesia. Thirty minutes after the initial bolus of the epidural a repeat computer analysis of 60-minute FHR tracing was obtained. Median values are reported for FHR parameters with statistical analysis performed by the Mann-Whitney U and Wilcoxon signed rank tests where appropriate. A power calculation was performed using a power of 90% to determine a required sample size of 28 patients. Statistical significance was set at P < .05. RESULTS: In early first stage of labor, there was no significant difference in pre- and postepidural anesthesia FHR baseline, accelerations of 10 and 15 beats per minute, episodes of high and low variation, and short- and long-term variation when using either narcotic or non-narcotic anesthetic agents. CONCLUSIONS: Thus, the clinician can consider the use of narcotic as well as non-narcotic continuous epidural anesthesia in the dosages used in our study with its attendant advantages without fear of obscuring the fetal heart rate tracing.

New materials for dielectric simulation of tissues.

Two novel materials have been developed to simulate the dielectric properties of human muscle and fat at 1000 MHz. These materials, which are based on ethanediol set with gelatine, are easily made and have good mechanical properties. The complex permittivity, epsilon *, of each material was measured with an open-ended coaxial sensor in conjunction with an automatic network analyser. Values of epsilon * at 1000 MHz and room temperature (49.4-24.4j for the muscle-equivalent material, 8.2-3.6j for the fat-equivalent) compared well with literature values for tissue at body temperature. Thermal properties were also considered. Specific heat capacities of the materials at room temperature were measured by differential scanning calorimetry and found to be very close to values predicted by theory. Densities were also measured and the thermal conductivities estimated. For comparison, new measurements were made of the specific heat and density of human muscle and fat at body temperature.

Determination of sulfur dioxide in grapes: comparison of the Monier-Williams method and two ion exclusion chromatographic methods.

Results for determination of sulfur dioxide in grapes were compared by 3 methods: the modified Monier-Williams method, acid distillation/ion exclusion chromatography with electrochemical detection (AD/IEC-EC), and alkali extraction/ion exclusion chromatography with electrochemical detection (AE/IEC-EC). An unusual positive response was observed during the later stage of the Monier-Williams distillation of both control grapes and sulfited grapes. Development of volatile acidic compounds in parallel with this Monier-Williams response and darkening of sample was also observed by collection in an alkali trap and analysis using anion exclusion chromatography and photodiode array detection. No parallel increase in sulfite was observed by the more selective AD/IEC-EC method, which clearly demonstrated that the response observed during the later stage of the Monier-Williams method is a false positive, probably due to caramelization reaction products. Monier-Williams results for grapes containing ca 10 ppm sulfite were in reasonably good agreement with those by either the AD/IEC-EC or AE/IEC-EC methods, presumably because the false positive response in the Monier-Williams analysis compensated for the somewhat incomplete recovery of sulfite. The AE/IEC-EC method is recommended because it is rapid, sensitive, straightforward, and free from interference. Accurate results by Monier-Williams analysis could be obtained by limiting distillation to 60 min and correcting for recovery.

Self-concepts of Costa Rican elementary school children.

The Martinek-Zaichkowsky Self-concept Scale was administered to 797 Costa Rican children in Grades 1 to 6. A three-way analysis of variance and Scheffé tests, used in conjunction with a 7 x 6 x 2 factorial design, showed significant differences between school types based on enrollment, grades, and sex. The highest self-concepts were found in the first grade and girls. Children in schools with enrollments under 50 scored significantly lower than those in larger schools. Findings were discussed in relation to literature for children in the USA.

The detection of post-gastrectomy deficiency syndromes in general practice.

Post-gastrectomy deficiency syndromes were investigated in a rural practice. The main finding was a high prevalence of iron deficiency both with and without anaemia. Regular checks on iron level in the follow-up of these patients is suggested.

Excepftonally strong near-bottom flows on the continental rise of nova scotia.

Recent current velocity measurements across the lower continental rise of Nova Scotia show a deep equatorwardflow with speeds (maximum, 73 centimeters per second) among the highest recorded for the deep sea. Silicate measurements indicate that this flow usually consists of southern-source (Antarctic) bottom water. These measurements confirm the existence of a second and deeper western boundary flow that was earlier inferredfrom geological observations.