Geological, multispectral, and meteorological imaging results from the Mars 2020 Perseverance rover in Jezero crater.

Perseverance's Mastcam-Z instrument provides high-resolution stereo and multispectral images with a unique combination of spatial resolution, spatial coverage, and wavelength coverage along the rover's traverse in Jezero crater, Mars. Images reveal rocks consistent with an igneous (including volcanic and/or volcaniclastic) and/or impactite origin and limited aqueous alteration, including polygonally fractured rocks with weathered coatings; massive boulder-forming bedrock consisting of mafic silicates, ferric oxides, and/or iron-bearing alteration minerals; and coarsely layered outcrops dominated by olivine. Pyroxene dominates the iron-bearing mineralogy in the fine-grained regolith, while olivine dominates the coarse-grained regolith. Solar and atmospheric imaging observations show significant intra- and intersol variations in dust optical depth and water ice clouds, as well as unique examples of boundary layer vortex action from both natural (dust devil) and Ingenuity helicopter-induced dust lifting. High-resolution stereo imaging also provides geologic context for rover operations, other instrument observations, and sample selection, characterization, and confirmation.

Respiratory sinus arrhythmia, parenting, and externalizing behavior in children with autism spectrum disorder.

Children with autism spectrum disorder exhibit significant difficulties with emotion regulation. Respiratory sinus arrhythmia is a biomarker for processes related to emotion regulation, with higher baseline rates linked to beneficial outcomes. Although reduction in respiratory sinus arrhythmia in response to challenge can index adaptive processes in community samples, excessive withdrawal may suggest loss of regulatory control among children with clinical concerns. Psychophysiological risk for problems may be protected against or exacerbated by parenting environments more or less supportive of the development of children's regulatory competence. Respiratory sinus arrhythmia was examined in 61 children with autism spectrum disorder ages 6-10 years in relation to externalizing behavior, and parenting was considered as a moderator. Respiratory sinus arrhythmia was obtained during laboratory tasks, and positive parenting, negative parenting, and children's externalizing behaviors were each indexed through multiple methods. Respiratory sinus arrhythmia reactivity interacted with negative, but not positive parenting. Higher respiratory sinus arrhythmia reactivity was associated with more externalizing behavior under conditions of higher negative parenting, but with lower externalizing behavior at lower levels of negative parenting. Similarly, negative parenting was only associated with externalizing behaviors in the context of high child respiratory sinus arrhythmia reactivity. Implications for our understanding of emotion regulation in children with autism spectrum disorder, and for related interventions, are discussed.

Predicting the development of pro-bullying bystander behavior: A short-term longitudinal analysis.

Pro-bullying bystander behavior is a key socio-contextual factor underlying the perpetuation of bullying, yet investigators know relatively little as to what contributes to its development. The current study uses a short-term longitudinal design to identify child characteristics and relationship qualities that predict pro-bullying bystander behavior over the course of one school year. Participants were 484 children (239 girls; Mage = 10.25 years). Children completed self-report measures of pro-bullying bystander behavior, empathy, moral disengagement, and perceived norms for defending, and peer-report measures of peer victimization and popularity. Main effects of fall empathy and moral disengagement emerged in the prediction of spring pro-bullying bystander behavior, although the latter just for boys. At low levels of perceived norms for defending, high levels of popularity and, for girls, high levels of peer victimization predicted heightened pro-bullying bystander behavior. Thus, anti-bullying efforts may benefit from targeting these social-cognitive and relational processes predictive of pro-bullying bystander behavior and fostering group norms that mitigate these risks.

Calcium- and Phosphorus-Supplemented Diet Increases Bone Mass after Short-Term Exercise and Increases Bone Mass and Structural Strength after Long-Term Exercise in Adult Mice.

Exercise has long-lasting benefits to bone health that may help prevent fractures by increasing bone mass, bone strength, and tissue quality. Long-term exercise of 6-12 weeks in rodents increases bone mass and bone strength. However, in growing mice, a short-term exercise program of 3 weeks can limit increases in bone mass and structural strength, compared to non-exercised controls. Short-term exercise can, however, increase tissue strength, suggesting that exercise may create competition for minerals that favors initially improving tissue-level properties over structural-level properties. It was therefore hypothesized that adding calcium and phosphorus supplements to the diet may prevent decreases in bone mass and structural strength during a short-term exercise program, while leading to greater bone mass and structural strength than exercise alone after a long-term exercise program. A short-term exercise experiment was done for 3 weeks, and a long-term exercise experiment was done for 8 weeks. For each experiment, male 16-week old C57BL/6 mice were assigned to 4 weight-matched groups-exercise and non-exercise groups fed a control or mineral-supplemented diet. Exercise consisted of treadmill running at 12 m/min, 30 min/day for 7 days/week. After 3 weeks, exercised mice fed the supplemented diet had significantly increased tibial tissue mineral content (TMC) and cross-sectional area over exercised mice fed the control diet. After 8 weeks, tibial TMC, cross-sectional area, yield force, and ultimate force were greater from the combined treatments than from either exercise or supplemented diet alone. Serum markers of bone formation (PINP) and resorption (CTX) were both decreased by exercise on day 2. In exercised mice, day 2 PINP was significantly positively correlated with day 2 serum Ca, a correlation that was weaker and negative in non-exercised mice. Increasing dietary mineral consumption during an exercise program increases bone mass after 3 weeks and increases structural strength after 8 weeks, making bones best able to resist fracture.

Reactivity of commercial benzodiazepine immunoassays to phenazepam.

Phenazepam is a long acting benzodiazepine that is not controlled in Canada, the United States or many European countries. The abuse of phenazepam has gained recent attention due to the number of hospitalizations and fatalities resulting from overdose. The compound is relatively potent with recommended doses of 0.5-1.0 mg, or 1/10th the recommended dose of diazepam, and is easy to obtain locally or from international suppliers via the internet. Increased risk of phenazepam overdose is attributed to its potency and the forms in which it is supplied. Individuals without scales or balances are prone to estimate dose amounts of powder visually, which can result in significant errors. The detection of phenazepam has been described using various methods including GC, GC/MS and LC/MS, but no data regarding the sensitivity of commercially available immunoassays exist. In this study, phenazepam-spiked urine samples were analyzed using five commercial instruments and two point of care devices. The concentrations of phenazepam required for detection ranged from 140-462 ng/mL, which is comparable to those of other benzodiazepines. Laboratorians and clinicians should be confident that phenazepam will be detected via most commercial drugs of abuse screens in patients after significant ingestion.