Conscious awareness is necessary to assess trust and mimic facial expressions, while pupils impact trust unconsciously.

People make rapid inferences about others' thoughts and intentions. For example, they observe facial movements and pupil size of others and unwittingly make use of this information when deciding whether to trust someone or not. However, whether spontaneous mimicry depends on visual awareness of the stimulus and whether these processes underlie trust decisions is still unknown. To investigate whether visual awareness modulates the relationship between emotional expressions, mimicry and trust, participants played a series of trust games and saw either their partners' faces with a neutral, happy or fearful expression, or their partners' eyes in which the pupil size was large, medium or small. Subjects' trust investments, facial movements and pupil responses were measured. In half of the trials, the stimuli were rendered invisible by continuous flash suppression. Results showed that facial expressions were mimicked and influenced trust decisions during the conscious condition, but not during the unconscious (suppressed) condition. The opposite was found for pupil size, which influenced trust decisions during states of unawareness. These results suggest that the neurobiological pathway linking the observation of facial expressions to mimicry and trust is predominantly conscious, whereas partner pupil size influences trust primarily when presented unconsciously. This article is part of the theme issue 'Cracking the laugh code: laughter through the lens of biology, psychology and neuroscience'.

Physiological synchrony is associated with attraction in a blind date setting.

Humans are social animals whose well-being is shaped by the ability to attract and connect with one another, often through brief interactions. In addition to physical features, a choreography of movements, physical reactions and subtle expressions may help promote attraction. Here, we measured the physiological dynamics between pairs of participants during real-life dating interactions outside the laboratory. Participants wore eye-tracking glasses with embedded cameras and devices to measure physiological signals including heart rate and skin conductance. We found that overt signals such as smiles, laughter, eye gaze or the mimicry of those signals were not significantly associated with attraction. Instead, attraction was predicted by synchrony in heart rate and skin conductance between partners, which are covert, unconscious and difficult to regulate. Our findings suggest that interacting partners' attraction increases and decreases as their subconscious arousal levels rise and fall in synchrony.

Physiological synchrony is associated with cooperative success in real-life interactions.

Cooperation is pivotal for society to flourish. To foster cooperation, humans express and read intentions via explicit signals and subtle reflections of arousal visible in the face. Evidence is accumulating that humans synchronize these nonverbal expressions and the physiological mechanisms underlying them, potentially influencing cooperation. The current study is designed to verify this putative linkage between synchrony and cooperation. To that end, 152 participants played the Prisoner's Dilemma game in a dyadic interaction setting, sometimes facing each other and sometimes not. Results showed that synchrony in both heart rate and skin conductance level emerged during face-to-face contact. However, only synchrony in skin conductance levels predicted cooperative success of dyads. Crucially, this positive linkage was strengthened when participants could see each other. These findings show the strong relationship between our bodily responses and social behavior, and emphasize the importance of studying social processes between rather than within individuals in real-life interactions.

Resonance-assisted stabilisation of hydrogen bonds probed by NMR spectroscopy and path integral molecular dynamics.

Path integral molecular dynamics and experimental NMR data are used to investigate resonance-assisted hydrogen bonds (RAHBs). When nuclear delocalisation is included in chemical shift calculations, the agreement with experiment is excellent, while static calculations show very poor performance. The results support the concept of RAHB, which has recently been questioned.

Separation of planar rotamers through intramolecular hydrogen bonding in polysubstituted 5-nitrosopyrimidines.

While purifying new polysubstituted 5-nitrosopyrimidines, the unique separation of pairs of rotamers as chemical species, stabilized by a single intramolecular hydrogen bond and differing only in nitroso group orientation, was achieved. This interesting stereochemical phenomenon is compared to the well-known atropisomerism.

[Vibrio cholerae 01 in a fish aquarium]. / Vibrio cholerae 01 v akváriu.

Vibrio cholerae 01 was detected from aquarium water and fish imported from Thailand and Sri Lanka. The infected fish were treated with antibiotics and the tanks and other aquatics were decontaminated. None of the persons taking care of the infected fish became ill; bacteriological analyses of fecal specimens of these persons were negative. The significance of the finding is discussed in view of possible transmission and incidence of cholera among aquarists in countries outside cholera endemic areas.

[Psychological condition of children from pregnancies after assisted reproduction in the third year of life]. / Psychický stav detí z tehotenství po asistované reprodukci ve tretím roce zivota.

OBJECTIVE: To analyse psychological development of children born after assisted reproductive technology. DESIGN: Psychological analysis of the child's development related to the technology of assisted reproduction, length of pregnancy and multiple birth was performed and compared with the control group. SETTING: Institute for the Care of Mother and Child, Prague. METHODS: Out of the total number of 123 children born after assisted reproductive technology during the 1st half of the year 1998 in the Center ISCARE IVF, psychological development was evaluated in 109 children (88.6%). Ninety four children from this sample were assessed using mental, motor and behavior scales of the Bayley Scales of Infant Development II. RESULTS: Mental and motor development of infants born after intracytoplasmatic injection (ICSI) and after in-vitro-fertilisation (IVF) was not significantly different. Fullterm singletons born after assisted reproductive technology did not differ from control fullterm children. There was a developmental delay in both fullterm and preterm children from multiple pregnancies in comparison to control children. No child had serious impairment of psychic functions (developmental index <50). There were no significant differences in behavior records between children born after assisted reproductive technology and control children, but some parents had problems in educational care of their children born after assisted reproductive technology. CONCLUSION: From children born after assisted reproductive technology, those from multiple pregnancies may be at risk for later psychological development. The occurrence of educational problems in assisted reproductive families indicates a need of accessible professional care in this field.

[Further development of neonates with severe pneumopathy]. / Dalsí vývoj novorozencu s tezkou formou pneumopatie.

OBJECTIVE: To assess the risk and the degree of possible unfavourable development in neonates with bronchopulmonal dysplasia and with congenital diaphragmatic hernia. DESIGN: Longitudinal monitoring of the mental, motoric and neurological development until the age of 2 years. Comparison of the findings with the result of polygraphic examination carried out at the expected time of birth. METHODS: The following children were monitored: a) 38 children with bronchopulmonal dysplasia born between the 24th and 33rd post-conception weeks; b) 18 children with congenital diaphragmatic hernia, of whom 3 children were born between the 34th and 36th post-conception weeks, while the remaining 15 children were born on the expected date. All children underwent polygraphic examinations (EEG - 8 channels, respiration, EKG, EOG and EMG) between the 38th and 42nd post-conception weeks. During the 1st and the 2nd years, their psychomotoric development and neurological status were repeatedly evaluated according to Bayley and Vlach, respectively. RESULTS: Up until the 2nd year of life, approximately 2/3 of the children in both monitored groups were developing favourably or satisfactorily. However, the development of the remaining 1/3 was not favourable: The children were mentally or motorically retarded and/or cerebral palsy developed in them. The polygraphic examination in the neonatal period predicted the favourable or unfavourable development of the monitored children with high probability. CONCLUSION: The study showed that in accordance with the data stated in the literature, the development of neural functions is seriously affected in a relatively high percentage of neonates with severe pneumopathy. Neonatal polygraphy can contribute to timely determination of the prognosis for these children. Children with serious neonatal pneumopathies need to be provided with dispensary care on a long-term basis, and professional consultancy and intervention programmes need to be ensured for them.

Application of micellar electrokinetic capillary chromatography for quantitative analysis of quercetin in plant materials.

A simple method for the routine determination of quercetin in biological samples was developed. The method consists of hydrolysis of bonded quercetin, its isolation and preconcentration on solid-phase extraction (SPE) column and a final analytical step using micellar electrokinetic capillary chromatography. The working range, linear range, the limit of quantification, and the measurement uncertainty were tested in validation. The method is suitable for quercetin determination in fruit and vegetable samples.

Phagocytosis of cadmium microcrystals by glass-adherent peripheral blood leucocytes of newborns with various perinatal risks.

Using cadmium microcrystals saturated with human serum albumin as particles for the phagocytic assay, the phagocytic activity of peripheral blood glass-adherent leucocytes of 32 preterm infants, 15 small-for-date newborns, 14 term newborns with perinatal asphyxia and 27 term newborns of diabetic mothers was compared with healthy term newborns and normal adults. A statistically significant increase in both the percent of phagocytosing cells and in the mean number of engulfed particles per cell was found in all groups of "stressed" infants as compared with cells of adults. No difference in the proportion of actively phagocytosing cells was found between term healthy and stressed neonates; as regards the mean number of ingested particles per cell, a slight increase (however, statistically not significant) was found in all groups of infants with perinatal risks compared with normal infants suggesting a temporary stimulation of these cells.