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Water-filled boreholes in cold ice refreeze in hours to days, and prior attempts to keep them open with antifreeze resulted in a plug of slush effectively freezing the hole even faster. Thus, antifreeze as a method to stabilize hot-water boreholes has largely been abandoned. In the hot-point drilling case, no external water is added to the hole during drilling, so earlier antifreeze injection is possible while the drill continues melting downward. Here, we use a cylindrical Stefan model to explore slush formation within the parameter space representative of hot-point drilling. We find that earlier injection timing creates an opportunity to avoid slush entirely by injecting sufficient antifreeze to dissolve the hole past the drilled radius. As in the case of hot-water drilling, the alternative is to force mixing in the hole after antifreeze injection to ensure that ice refreezes onto the borehole wall instead of within the solution as slush.
With human influences driving populations of apex predators into decline, more information is required on how factors affect species at national and global scales. However, camera-trap studies are seldom executed at a broad spatial scale. We demonstrate how uniting fine-scale studies and utilizing camera-trap data of non-target species is an effective approach for broadscale assessments through a case study of the brown hyaena Parahyaena brunnea. We collated camera-trap data from 25 protected and unprotected sites across South Africa into the largest detection/non-detection dataset collected on the brown hyaena, and investigated the influence of biological and anthropogenic factors on brown hyaena occupancy. Spatial autocorrelation had a significant effect on the data, and was corrected using a Bayesian Gibbs sampler. We show that brown hyaena occupancy is driven by specific co-occurring apex predator species and human disturbance. The relative abundance of spotted hyaenas Crocuta crocuta and people on foot had a negative effect on brown hyaena occupancy, whereas the relative abundance of leopards Panthera pardus and vehicles had a positive influence. We estimated that brown hyaenas occur across 66% of the surveyed camera-trap station sites. Occupancy varied geographically, with lower estimates in eastern and southern South Africa. Our findings suggest that brown hyaena conservation is dependent upon a multi-species approach focussed on implementing conservation policies that better facilitate coexistence between people and hyaenas. We also validate the conservation value of pooling fine-scale datasets and utilizing bycatch data to examine species trends at broad spatial scales.
Prospective longitudinal studies of idiopathic autism spectrum disorder (ASD) have provided insights into early symptoms and predictors of ASD during infancy, well before ASD can be diagnosed at age 2–3 years. However, research on the emergence of ASD in disorders with a known genetic etiology, contextualized in a developmental framework, is currently lacking. Using a biobehavioral multimethod approach, we (a) determined the rate of ASD in N = 51 preschoolers with fragile X syndrome (FXS) using a clinical best estimate (CBE) procedure with differential diagnoses of comorbid psychiatric disorders and (b) investigated trajectories of ASD symptoms and physiological arousal across infancy as predictors of ASD in preschoolers with FXS. ASD was not diagnosed if intellectual ability or psychiatric disorders better accounted for the symptoms. Our results determined that 60.7% of preschoolers with FXS met the Diagnostic and Statistical Manual of Mental Disorders (fifth edition) (DSM-5) criteria for ASD using the CBE procedure. In addition, 92% of these preschoolers presented with developmental delay and 45.4% also met criteria for psychiatric disorders, either anxiety, ADHD, or both. ASD diagnoses in preschoolers with FXS were predicted by elevated scores on traditional ASD screeners in addition to elevated autonomic arousal and avoidant eye contact from infancy.
Decisions to treat large-vessel occlusion with endovascular therapy (EVT) or intravenous alteplase depend on how physicians weigh benefits against risks when considering patients’ comorbidities. We explored EVT/alteplase decision-making by stroke experts in the setting of comorbidity/disability.
In an international multi-disciplinary survey, experts chose treatment approaches under current resources and under assumed ideal conditions for 10 of 22 randomly assigned case scenarios. Five included comorbidities (cancer, cardiac/respiratory/renal disease, mild cognitive impairment [MCI], physical dependence). We examined scenario/respondent characteristics associated with EVT/alteplase decisions using multivariable logistic regressions.
Among 607 physicians (38 countries), EVT was chosen less often in comorbidity-related scenarios (79.6% under current resources, 82.7% assuming ideal conditions) versus six “level-1A” scenarios for which EVT/alteplase was clearly indicated by current guidelines (91.1% and 95.1%, respectively, odds ratio [OR] [current resources]: 0.38, 95% confidence interval 0.31–0.47). However, EVT was chosen more often in comorbidity-related scenarios compared to all other 17 scenarios (79.6% versus 74.4% under current resources, OR: 1.34, 1.17–1.54). Responses favoring alteplase for comorbidity-related scenarios (e.g. 75.0% under current resources) were comparable to level-1A scenarios (72.2%) and higher than all others (60.4%). No comorbidity independently diminished EVT odds when considering all scenarios. MCI and dependence carried higher alteplase odds; cancer and cardiac/respiratory/renal disease had lower odds. Being older/female carried lower EVT odds. Relevant respondent characteristics included performing more EVT cases/year (higher EVT-, lower alteplase odds), practicing in East Asia (higher EVT odds), and in interventional neuroradiology (lower alteplase odds vs neurology).
Moderate-to-severe comorbidities did not consistently deter experts from EVT, suggesting equipoise about withholding EVT based on comorbidities. However, alteplase was often foregone when respondents chose EVT. Differences in decision-making by patient age/sex merit further study.
OBJECTIVES/GOALS: Access to pediatric subspecialty care varies by sociodemographic factors. Providers for gender diverse youth (GDY) are rare, and GDY face health disparities, stigma, and discrimination. We examined the association between GDY access to medical and mental health care and rurality, race, parental education, and other GDY-specific factors. METHODS/STUDY POPULATION: We surveyed parents of GDY (<18 years old) across the United States. Participants were recruited through online communities and listserves specific to parents of GDY. We determined associations between access to gender-specific medical or mental health providers and rurality, race, parental education, as well as other GDY-specific factors including age, time since telling their parent their gender identity, parent-adolescent communication, parent stress, and gender identity using chi-square or Fisher’s exact tests. We calculated adjusted odds ratios using logistic regression models. RESULTS/ANTICIPATED RESULTS: We surveyed 166 parents and caregivers from 31 states. The majority (73.2%) identified as white, 66.5% had earned a bachelor’s degree or higher, and 7.6% lived in a zip code designated rural by the Federal Office of Rural Health Policy. We found no evidence of association between reported GDY access to medical or mental health care and race, parental education, or rurality. We did find a significant univariate association between access to mental health care and feminine (either female or transfeminine/transfemale) gender identity (p = 0.033, OR 2.60, 95% CI 1.06 – 6.36). After controlling for parent-adolescent communication in a backwards elimination logistic regression model, it was no longer significant (p = 0.137, OR 2.05, 95% CI 0.80 – 5.25). DISCUSSION/SIGNIFICANCE OF IMPACT: Despite rurality, race, and parental education impacting access to pediatric subspecialty care, we failed to find these associations among GDY accessing gender care. There is a need to better understand structural and societal barriers to care for this population including the impact of stigma and discrimination.
Internet gaming disorder appears to be associated with self-concept deficits and increased identification with one's avatar. For increased social network use, the few existing studies suggest striatal-related positive social feedback as an underlying factor. Furthermore, few study findings indicate that internet addicts generally have problems in emotional inhibitory control processing.
Pathological and addicted internet gamers as well as social network users were compared with healthy controls regarding psychometric and neurobiological measures of self-concept-related characteristics, avatar identification and emotional inhibitory control processing.
Results and conclusion
Psychometric results indicated that both subgroups showed higher self-concept deficits compared to healthy controls. Neurobiologically, different brain activation patterns were observed in the subgroups during self-knowledge retrieval and inhibition of emotional stimuli. Furthermore, addicted internet gamers showed a higher identification with the own avatar, mirrored in an increased left angular gyrus activation, a region functionally associated with identification processing and feelings of empathy.
These findings provide a starting point for the deduction of specific psychotherapeutic treatment approaches for addicted internet gamers and social network users.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
While echocardiographic parameters are used to quantify ventricular function in infants with single ventricle physiology, there are few data comparing these to invasive measurements. This study correlates echocardiographic measures of diastolic function with ventricular end-diastolic pressure in infants with single ventricle physiology prior to superior cavopulmonary anastomosis.
Data from 173 patients enrolled in the Pediatric Heart Network Infant Single Ventricle enalapril trial were analysed. Those with mixed ventricular types (n = 17) and one outlier (end-diastolic pressure = 32 mmHg) were excluded from the analysis, leaving a total sample size of 155 patients. Echocardiographic measurements were correlated to end-diastolic pressure using Spearman’s test.
Median age at echocardiogram was 4.6 (range 2.5–7.4) months. Median ventricular end-diastolic pressure was 7 (range 3–19) mmHg. Median time difference between the echocardiogram and catheterisation was 0 days (range −35 to 59 days). Examining the entire cohort of 155 patients, no echocardiographic diastolic function variable correlated with ventricular end-diastolic pressure. When the analysis was limited to the 86 patients who had similar sedation for both studies, the systolic:diastolic duration ratio had a significant but weak negative correlation with end-diastolic pressure (r = −0.3, p = 0.004). The remaining echocardiographic variables did not correlate with ventricular end-diastolic pressure.
In this cohort of infants with single ventricle physiology prior to superior cavopulmonary anastomosis, most conventional echocardiographic measures of diastolic function did not correlate with ventricular end-diastolic pressure at cardiac catheterisation. These limitations should be factored into the interpretation of quantitative echo data in this patient population.
Research on mate selection has taken two approaches. One approach is to study mate selection criteria, asking people how important various characteristics are in selecting a mate. The other approach is to study matching between spouses in married couples.
From an evolutionary psychology perspective, it has been argued that men are seeking women who are physically attractive, as an indicator of fertility, while women are seeking men of high status, to support themselves and their offspring (Buss, 1989). Yet the mean ratings in Buss’s data indicate that both physical attractiveness and social status were rated only moderately important for both men and women across thirty-seven countries, even though there were gender differences.
This book reports the findings of a cross-cultural study to update and extend the groundbreaking Boston Couples Study and other research on intimate relationships. It develops comprehensive models of relationship dynamics and makes explicit comparisons across relationship types and cultural regions, which are missing in the research literature. It is written in a style appropriate for college students, researchers, therapists, and others.
In 1972, Zick Rubin, Anne Peplau, and I began a pioneering longitudinal study of college-age dating couples, known as the Boston Couples Study. This research has been cited in numerous textbooks and journal articles. Our first of many articles (Hill, Rubin, & Peplau, 1976) has been cited more 750 times (Google Scholar, 2018).
Blau (1964) viewed social interaction as a process of social exchange, in which one person gives rewards to another, and the other is obligated to reciprocate by giving something appropriate back. We are taught a norm that we are supposed to reciprocate (such as Christmas gifts and birthday presents), but even more important is the need to reciprocate to obtain future rewards. What is exchanged includes not only tangible things like goods and assistance but also intangible things like advice and love. For example, mothers who unselfishly do things for their children want love in return.
Maslow argued that the set of needs listed on the bottom must be met first; then when each set is met, the next higher set emerges. While it is true that the bottom level is necessary for survival, the answers to the cognitive and aesthetic needs teach us how to meet all of the other needs. And meeting social needs provides social support to cope with the stresses involved in meeting needs. Hence, the hierarchical nature of the needs can be questioned.
Social and other needs provide reasons and goals for seeking intimate relationships. Baumeister and Leary (1995) argued that humans have a fundamental need for belonging, and this is included as relatedness along with autonomy and competence as three primary motivations in Self-Determination Theory (Ryan & Deci, 2017). A lack of interpersonal relationships can lead to loneliness (Peplau & Perlman, 1982). Weiss (1974) distinguished between two types of loneliness: emotional (due to lack of intimate relationships) and social (due to lack of a social network). DiTommaso and Spinner (1997) further distinguished between romantic emotional loneliness and family emotional loneliness. Hence, avoiding loneliness is a major reason for seeking an intimate relationship. In the Boston Couples Study, those who broke up reported feeling lonely and depressed (Hill, Rubin, & Peplau, 1976). In addition, loneliness is a major risk factor for mortality, as important as physical factors (Holt-Lunstad et al., 2015).
As noted in the Introduction to this book, there has been a great deal of research on relationships, but very little of it has been cross-cultural. Even less has involved relationships other than marriage. A notable exception is a recent anthology about grandparents in various cultures (Schwalb & Hossain, 2017). Also of interest is a one-year longitudinal study that found that Rusbult’s Investment Theory predicted staying best friends among adolescents in the Netherlands (Branje et al., 2007). Another study explored social support among siblings (brothers or sisters) in the Netherlands (Voorpostel & Blieszner, 2008).
Chapter 1 introduced the statistical tools and conceptual tools used in this book. Future research is needed using these tools in the following ways.
Previous research has indicated that social relationships are important predictors of well-being, but that the quality of the relationships is more important than merely having the relationships (Saphire-Bernstein & Taylor, 2013).
Happiness is viewed by psychologists as an emotional response, while life satisfaction is viewed as a cognitive evaluation (Diener, Oishi, & Lucas, 2002). Across a sample of 123 countries, Tay and Diener (2011) found that positive feelings were most associated with fulfilling social and esteem needs, while life evaluation was most associated with fulfilling basic needs such as food and shelter.
William James and Carl Lange proposed in the 1880s that every emotion has a unique pattern of physiological responses (Cannon, 1927), but when researchers studied emotional responses, they found overlapping responses, such as increased heart rate for anger, fear, and surprise. So Schachter and Singer (1962) proposed that all emotions have the same physiological arousal, and what differentiates them is labeling based on cognitive cues. For example, my heart is racing and I look around and see that I am in a street and a car is approaching me; therefore, I must be afraid.
But while physiological responses often overlap among emotions, they are not always the same. For example, blood rushes to the face when angry but away from the face when frightened, and heart rate slows when sad. And in most cases, the cue comes before the arousal and indeed causes the arousal, e.g., my heart is racing because I saw the approaching car. Hence, researchers thought it was impossible to measure emotions, including love.
Variations in the levels of factors that predict Having a Current Partner, and variations in the levels of factors that predict Relationship Satisfaction and Relationship Commitment, are explored in this chapter. These variations are discussed in terms of overall means and standard deviations, and variations in means across relationship types and across cultural regions.
The means (averages) and standard deviations (s.d.) of Having a Current Partner and of the Comprehensive Factors predicting Having a Current Partner are listed in Table 11.1. The standard deviations indicate the amount of individual variation in responses across all participants in the study. The possible responses for Having a Current Partner and for having had a previous partner are 0=NO to 1=YES, hence those means indicate percentages expressed as decimals. Age varied from 18 to 84. The other factors have possible responses from 0=NOT AT ALL to 8=EXTREMELY.