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Economic hardship is known to shape children’s self-regulation, yet little is understood about how fluctuations in hardship unfold over time and whether different patterns of unpredictability carry unique developmental consequences. Using a socioeconomically diverse sample, we tracked families’ subjective economic hardship across 15–36 monthly assessments and applied an environmental statistics framework to quantify four indices of unpredictability: changepoints in mean, changepoints in variance, coefficient of variation, and noise. PCA identified two distinct forms of economic unpredictability: one marked by frequent, unpredictable hardship, and another by infrequent but abrupt hardship. Economic unpredictability was disproportionately experienced by racially minoritized and lower-income families in our sample, reinforcing structural inequities in economic resources. Relations between these indices and caregiver-reported measures of family routines and day-to-day unpredictability were weak, suggesting wide heterogeneity in the ways families adapt to economic unpredictability. Leveraging propensity score methods, we isolated the effects of unpredictability from hardship severity, finding that both were associated with greater self-regulation challenges in early childhood, with the strongest effects for hardship severity. These findings underscore the importance of capturing economic hardship as a dynamic and multidimensional experience, with implications for policy efforts aimed at promoting stability in families’ access to resources over time.
The association between cannabis use and suicidality has been established, but details on impacts of legalisation, as well as long-term service use, have had limited attention.
Aims
To examine if changes are present in suicide presentations with access to legal cannabis.
Method
This study employed administrative database and medical record reviews to identify two cohorts of patients presenting with suicidal ideation/attempts and cannabis use to emergency departments, for two periods: 17 October 2018 to 30 April 2019, and 17 October 2020 to 30 April 2021. Demographic and clinical outcome data were obtained, and emergency department healthcare usage for 2 years before and 2 years after index encounter were compared, to further understand emergency department presentations for the same complaint.
Results
Number of emergency department encounters following the index visit and number of emergency department encounters specifically relating to suicidality following the index visit were significantly different between cohorts (t = 2.05, P = 0.042; t = 2.23, P = 0.027, respectively), with the immediate post-cannabis legalisation period demonstrating greater numbers of subsequent emergency department visits for suicidality. Additional associations were found between personality disorders and repeat emergency department visits related to cannabis use.
Conclusions
There appears to be stability in the patient profile of those presenting to the emergency department with a complaint relating to suicide while reporting cannabis use from the period directly following legalisation in Canada, to a similar time frame 2 years later despite reported increased use of cannabis in the general population over this period. Despite the rising potency and access to legal cannabis, suicide risk remains stable, although concerning.
Informed by the National Institute of Mental Health's Research Domain Criteria (RDoC) and developmental psychopathology frameworks, the current study used cortisol area under the curve with respect to ground (AUCg) as an index of differential sensitivity to context, which was expected to predispose young children with elevated vulnerability to adverse caregiving experiences and adaptive sensitivity to intervention effects. Particularly, the study aimed to determine whether improving caregivers’ responsive parenting through the Filming Interactions to Nurture Development (FIND) intervention would buffer children's biologically embedded vulnerability to caregivers’ depressive symptoms. Data were derived from a randomized controlled trial using pretest–posttest design with low-income families of children aged 4 to 36 months (N = 91). Young children's differential sensitivity was measured using cortisol AUCg during a structured stress paradigm. As hypothesized, children whose cortisol AUCg indicated greater sensitivity to social context exhibited more internalizing and externalizing behaviors in relation to caregivers’ elevated depressive symptoms. Critically, the intervention program was effective in attenuating psychopathology symptoms among the more biologically sensitive children. As proven by rigorous statistical tests, the findings of this study partially supported the differential susceptibility hypotheses, indicating both greater vulnerability to adverse conditions and responsiveness to intervention among children with high levels of cortisol AUCg.
In April 2019, the U.S. Fish and Wildlife Service (USFWS) released its recovery plan for the jaguar Panthera onca after several decades of discussion, litigation and controversy about the status of the species in the USA. The USFWS estimated that potential habitat, south of the Interstate-10 highway in Arizona and New Mexico, had a carrying capacity of c. six jaguars, and so focused its recovery programme on areas south of the USA–Mexico border. Here we present a systematic review of the modelling and assessment efforts over the last 25 years, with a focus on areas north of Interstate-10 in Arizona and New Mexico, outside the recovery unit considered by the USFWS. Despite differences in data inputs, methods, and analytical extent, the nine previous studies found support for potential suitable jaguar habitat in the central mountain ranges of Arizona and New Mexico. Applying slightly modified versions of the USFWS model and recalculating an Arizona-focused model over both states provided additional confirmation. Extending the area of consideration also substantially raised the carrying capacity of habitats in Arizona and New Mexico, from six to 90 or 151 adult jaguars, using the modified USFWS models. This review demonstrates the crucial ways in which choosing the extent of analysis influences the conclusions of a conservation plan. More importantly, it opens a new opportunity for jaguar conservation in North America that could help address threats from habitat losses, climate change and border infrastructure.
The majority of children living in foster care in the United States have a history of maltreatment and/or disrupted caregiving. Maltreatment in early childhood adversely affects development at many levels, including neurobiology and behavior. One neurobiological measure associated with maltreatment is alpha electroencephalogram (EEG) asymmetry. Prior research has found greater right frontal asymmetry among children with a history of maltreatment. However, little research has been extended developmentally downward to examine alpha asymmetry and its behavioral correlates among toddlers in foster care; this was the purpose of the present study. Differences in EEG asymmetry were examined between a sample of foster toddlers (mean age = 3.21 years, n = 38) and a community comparison, low-income sample without a history of foster care (mean age = 3.04 years, n = 16). The toddlers in the foster care group exhibited greater right alpha asymmetry, primarily driven by differences in parietal asymmetry. Neither frontal nor parietal asymmetry were clearly related to internalizing or externalizing behaviors, measured concurrently or at previous time points. These findings reveal differences in alpha EEG asymmetry among toddlers in foster care, and highlight the need to better understand associations between neurobiological and behavioral functioning following early adversity.
A recent suicidal drive hypothesis posits that psychotic experiences (PEs) may serve to externalize internally generated and self-directed threat (i.e., self-injurious/suicidal behavior [SIB]) in order to optimize survival; however, it must first be demonstrated that such internal threat can both precede and inform PEs. The current study conducted the first known bidirectional analysis of SIB and PEs to test whether SIB could be considered as a plausible antecedent for PEs. Prospective data were utilized from the Environmental Risk (E-Risk) Longitudinal Twin Study, a nationally representative birth cohort of 2232 twins, that captured SIB (any self-harm or suicidal attempt) and PEs at ages 12 and 18 years. Cross-lagged panel models demonstrated that the association between SIB at age 12 and PEs at age 18 was as strong as the association between PEs at age 12 and SIB at age 18. Indeed, the best representation of the data was a model where these paths were constrained to be equal (OR = 2.48, 95% CI = 1.63–3.79). Clinical interview case notes for those who reported both SIB and PEs at age 18, revealed that PEs were explicitly characterized by SIB/threat/death-related content for 39% of cases. These findings justify further investigation of the suicidal drive hypothesis.
This study examined the impact of a school readiness intervention on external response monitoring in children in foster care. Behavioral and event-related potential (ERP) data were collected during a flanker task from children who received the Kids In Transition to School (KITS) Program (n = 26) and children who received services as usual (n = 19) before and after the intervention. While there were no significant group differences on the behavioral data, the ERP data for the two groups of children significantly differed. Specifically, in contrast to the children who received services as usual, the children who received the KITS Program displayed greater amplitude differences between positive and negative performance feedback over time for the N1, which reflects early attention processes, and feedback-related negativity, which reflects evaluation processes. In addition, although the two groups did not differ on amplitude differences between positive and negative performance feedback for these ERP components before the intervention, the children who received the KITS Program displayed greater amplitude differences than the children who received services as usual after the intervention. These results suggest that the KITS Program had an effect on responsivity to external performance feedback, which may be beneficial during the transition into kindergarten.
Maltreated children in foster care are at high risk for dysregulated hypothalamus–pituitary–adrenal (HPA) axis functioning and educational difficulties. The present study examined the effects of a short-term school readiness intervention on HPA axis functioning in response to the start of kindergarten, a critical transition marking entry to formal schooling, and whether altered HPA axis functioning influenced children's school adjustment. Compared to a foster care comparison group, children in the intervention group showed a steeper diurnal cortisol slope on the first day of school, a pattern previously observed among nonmaltreated children. A steeper first day of school diurnal cortisol slope predicted teacher ratings of better school adjustment (i.e., academic performance, appropriate classroom behaviors, and engagement in learning) in the fall of kindergarten. Furthermore, the children's HPA axis response to the start of school mediated the effect of the intervention on school adjustment. These findings support the potential for ameliorative effects of interventions targeting critical transitional periods, such as the transition of formal schooling. This school readiness intervention appears to influence stress neurobiology, which in turn facilitates positive engagement with the school environment and better school adjustment in children who have experienced significant early adversity.
Modern scholarship on Arabs in the pre-Islamic period has focused on Rome's Arab allies—the so-called “Jafnids” or “Ghassānids,” with much less attention paid to Persia's Arab allies, the so-called “Naṣrid” or “Lakhmid” dynasty of Arab leaders at al-Ḥīrah in Iraq. This article examines select pre-Islamic sources for the Persian Arabs, showing that even with the meager evidence available to us, and the lack of archaeological material, it is possible to draw a relatively complex portrait of the Persian Arabs. This article situates the Persian Arabs as important figures in some key themes and phenomena of late antiquity, such as the growth of Christian communities, the conflict between Rome and Persia, and the struggle for influence in the Arabian peninsula.
Childhood maltreatment has lasting negative effects throughout the life span. Early intervention research has demonstrated that these effects can be remediated through skill-based, family-centered interventions. However, less is known about plasticity during adolescence, and whether interventions are effective many years after children experience maltreatment. This study investigated this question by examining adolescent girls' ability to make advantageous decisions in the face of risk using a validated decision-making task; performance on this task has been associated with key neural regions involved in affective processing and executive functioning. Maltreated foster girls (n = 92), randomly assigned at age 11 to either an intervention designed to prevent risk-taking behaviors or services as usual (SAU), and nonmaltreated age and socioeconomic status matched girls living with their biological parent(s) (n = 80) completed a decision-making task (at age 15–17) that assessed risk taking and sensitivity to expected value, an index of advantageous decision making. Girls in the SAU condition demonstrated the greatest decision-making difficulties, primarily for risks to avoid losses. In the SAU group, frequency of neglect was related to greater difficulties in this area. Girls in the intervention condition with less neglect performed similarly to nonmaltreated peers. This research suggests that early maltreatment may impact decision-making abilities into adolescence and that enriched environments during early adolescence provide a window of plasticity that may ameliorate these negative effects.
Risk factors for the childhood development of co-occurring internalizing and externalizing symptoms are not well understood, despite a high prevalence and poor clinical outcomes associated with this co-occurring phenotype. We examined inherited and environmental risk factors for co-occurring symptoms in a sample of children adopted at birth and their birth mothers and adoptive mothers (N = 293). Inherited risk factors (i.e., birth mothers' processing speed and internalizing symptoms) and environmental risk factors (i.e., adoptive mothers' processing speed, internalizing symptoms, and uninvolved parenting) were examined as predictors for the development of internalizing-only, externalizing-only, or co-occurring symptoms using structural equation modeling. Results suggested a unique pattern of predictive factors for the co-occurring phenotype, with risk conferred by adoptive mothers' uninvolved parenting, birth mothers' slower processing speed, and the birth mothers' slower processing speed in tandem with adoptive mothers' higher internalizing symptoms. Additional analyses indicated that when co-occurring-symptom children were incorporated into internalizing and externalizing symptom groups, differential risk factors for externalizing and internalizing symptoms emerged. The findings suggest that spurious results may be found when children with co-occurring symptoms are not examined as a unique phenotypic group.
Silicon carbide power devices are purported to be capable of operating at very high temperatures. Current commercially available SiC MOSFETs from a number of manufacturers have been evaluated to understand and quantify the aging processes and temperature dependencies that occur when operated up to 350°C. High temperature constant positive bias stress tests demonstrated a two times increase in threshold voltage from the original value for some device types, which was maintained indefinitely but could be corrected with a long negative gate bias. The threshold voltages were found to decrease close to zero and the on-state resistances increased quite linearly to approximately five or six times their room temperature values. Long term thermal aging of the dies appears to demonstrate possible degradation of the ohmic contacts. This appears as a rectifying response in the I-V curves at low drain-source bias. The high temperature capability of the latest generations of these devices has been proven independently; provided that threshold voltage management is implemented, the devices are capable of being operated and are free from the effects of thermal aging for at least 70 hours cumulative at 300°C.
In this paper, high temperature (>1400°C) thermal oxidation has been applied, for the first time, to 4H-SiC PiN diodes with thick (110 μm) drift regions, for the purpose of increasing the carrier lifetime in the semiconductor. PiN diodes were fabricated using 4H-SiC material that had undergone thermal oxidation performed at 1400°C, 1500°C and 1600°C, then were electrically characterized. Forward current-voltage (I-V) measurements showed that thermally oxidized PiN diodes exhibited considerably improved electrical characteristics, with devices oxidized at 1500°C having a forward voltage drop (VF) of 4.15 V and a differential on-resistance (Ron,diff) of 8.9 mΩ-cm2 at 100 A/cm2 and 25°C. Compared to typical control sample PiN diode characteristics, this equated to an improvement of 8% and 23% for VF and Ron,diff, respectively. From analysis of the reverse recovery characteristics, the carrier lifetime of the PiN diodes oxidized at 1500°C was found to be 1.05 μs, which was an improvement of around 30% compared to the control sample PiN diodes.
Although 3C-SiC has a narrower bandgap than 4H-SiC, it is the only SiC polytype that can be grown directly over large area silicon substrates. It has the potential to provide a more economical choice than 4H-SiC for intermediate power devices, such as inverters for electric vehicles. To fabricate a vertical device on 3C-SiC, the Si substrate is usually removed either by etching or polishing. Neither of these processes is economical nor efficient. In this paper we propose a lateral Schottky diode design for 3C-SiC on Si structure. 2D finite element simulations using ATLAS showed that a breakdown voltage beyond 1200 V can be achieved with a 4 μm thick epilayer. Physical models used for 3C-SiC/Si power devices simulations are introduced. Advantages of lateral 3C-SiC/Si diodes over free standing 3C-SiC are also discussed.
Half a century of research and program evaluation has fueled a diverse landscape of early childhood policies and practices that produce a range of positive effects on the life prospects of children who face the burdens of significant adversity. Drawing on advances in neurobiology, developmental psychology, developmental psychopathology, and prevention science, this paper presents a framework for elucidating underlying causal mechanisms that explain differences in outcomes, formulating enhanced theories of change about how to shift developmental trajectories, designing creative interventions and rethinking the concept of a two-generation strategy to produce breakthrough impacts, and launching a new era of investment in young children and their families that will achieve greater reductions in intergenerational disparities in learning, behavior, and health than those produced by current best practices. Particular attention is focused on the hypothesis that substantially better outcomes for vulnerable, young children could be achieved by greater attention to strengthening the resources and capabilities of the adults who care for them rather than by continuing to focus primarily on the provision of child-focused enrichment, parenting education, and informal support. Central to achieving this goal is the need to establish an innovation-friendly environment that embraces fast-cycle sharing, supports risk taking, and celebrates learning from failure.
Children in foster care have often encountered a range of adverse experiences, including neglectful and/or abusive care and multiple caregiver transitions. Prior research findings suggest that such experiences negatively affect inhibitory control and the underlying neural circuitry. In the current study, event-related functional magnetic resonance imaging was employed during a go/no go task that assesses inhibitory control to compare the behavioral performance and brain activation of foster children and nonmaltreated children. The sample included two groups of 9- to 12-year-old children: 11 maltreated foster children and 11 nonmaltreated children living with their biological parents. There were no significant group differences on behavioral performance on the task. In contrast, patterns of brain activation differed by group. The nonmaltreated children demonstrated stronger activation than did the foster children across several regions, including the right anterior cingulate cortex, the middle frontal gyrus, and the right lingual gyrus, during correct no go trials, whereas the foster children displayed stronger activation than the nonmaltreated children in the left inferior parietal lobule and the right superior occipital cortex, including the lingual gyrus and cuneus, during incorrect no go trials. These results provide preliminary evidence that the early adversity experienced by foster children impacts the neural substrates of inhibitory control.