A Foot in Both Worlds: Asian Americans' Perceptions of Asian, White, and Racially Ambiguous Faces

Past research on racial perception has often focused on responses from White participants, making it difficult to determine the role of perceiver race in the perception of others. Similarly, studies examining perceptions of individuals whose racial category membership is unclear have not systematically examined responses from non-Whites. This was addressed by showing Asian participants pictures of Whites, Asians, and racially ambiguous White-Asian faces. Event-related potentials were recorded to measure early attention responses. Participants initially oriented more to outgroup White than ingroup Asian or racially ambiguous faces. Shortly after that, they showed sensitivity to the racial context in which the faces were presented, more deeply processing ingroup Asian and racially ambiguous faces when they were seeing lots of other Asians, but more deeply processing outgroup White and racially ambiguous faces when they were seeing lots of other Whites. Still later, responses were more sensitive to the objective physical properties of the faces, with racially ambiguous faces differentiated from both Whites and Asians. These results demonstrate the fluidity of racial processing, and when compared to responses obtained from White participants, show how perceiver race and racial context influences attention to racial cues

Probing prejudice with startle eyeblink modification: A marker of attention, emotion, or both?

In social neuroscience research, startle eyeblink modification can serve as a marker of emotion, but it is less clear whether it can also serve as a marker of prejudice. In Experiment 1, 30 White students viewed photographs of White and Black targets while the startle eyeblink reflex and facial EMG from the brow and cheek regions were recorded. Prejudice was related to facial EMG activity, but not to startle modification, which instead appeared to index attention to race. To test further whether racial categorizations are associated with differential attention, a dual-task paradigm was used in Experiment 2. Fifty-four White and fifty-five Black participants responded more slowly to a tone presented when viewing a racial outgroup member or a negative stimulus, indicating that both draw more attention than ingroup members or positive stimuli. We conclude that startle modification is useful to index differential attention to groups when intergroup threat is low

Hyperoxia impairs alveolar formation and induces senescence through decreased histone deacetylase activity and up-regulation of p21 in neonatal mouse lung

Alveolar development comprises the transition of lung architecture from saccules to gas-exchange units during late gestation and early postnatal development. Exposure to hyperoxia disrupts developmental signaling pathways and causes alveolar hypoplasia as seen in bronchopulmonary dysplasia affecting preterm human newborns. Expanding literature suggests that epigenetic changes due to environmental triggers during development may lead to genetically heritable changes in gene expression. Given recent data on altered histone deacetylase (HDAC) activity in lungs of humans and animal models with airspace enlargement/emphysema, we hypothesized that alveolar hypoplasia from hyperoxia exposure in neonatal mice is a consequence of cell cycle arrest and reduced HDAC activity and up-regulation of the cyclin-dependent kinase inhibitor, p21. We exposed newborn mice to hyperoxia and compared lung morphologic and epigenetic changes to room air controls. Further, we pretreated a subgroup of animals with the macrolide antibiotic azithromycin (AZM), known to possess anti-inflammatory properties. Our results showed that hyperoxia exposure resulted in alveolar hypoplasia and was associated with decreased HDAC1 and HDAC2 and increased p53 and p21 expression. Further, AZM did not confer protection against hyperoxia-induced alveolar changes. These findings suggest that alveolar hypoplasia due to hyperoxia is mediated by epigenetic changes affecting cell cycle regulation/senescence during lung development

Test-retest variability of high resolution positron emission tomography (PET) imaging of cortical serotonin (5HT2A) receptors in older, healthy adults

<p>Abstract</p> <p>Background</p> <p>Position emission tomography (PET) imaging using [¹⁸F]-setoperone to quantify cortical 5-HT_2Areceptors has the potential to inform pharmacological treatments for geriatric depression and dementia. Prior reports indicate a significant normal aging effect on serotonin 5HT_2Areceptor (5HT_2AR) binding potential. The purpose of this study was to assess the test-retest variability of [¹⁸F]-setoperone PET with a high resolution scanner (HRRT) for measuring 5HT_2AR availability in subjects greater than 60 years old. Methods: Six healthy subjects (age range = 65–78 years) completed two [¹⁸F]-setoperone PET scans on two separate occasions 5–16 weeks apart.</p> <p>Results</p> <p>The average difference in the binding potential (BP_ND) as measured on the two occasions in the frontal and temporal cortical regions ranged between 2 and 12%, with the lowest intraclass correlation coefficient in anterior cingulate regions.</p> <p>Conclusion</p> <p>We conclude that the test-retest variability of [¹⁸F]-setoperone PET in elderly subjects is comparable to that of [¹⁸F]-setoperone and other 5HT_2AR radiotracers in younger subject samples.</p

DNA Methylation in the Human Cerebral Cortex Is Dynamically Regulated throughout the Life Span and Involves Differentiated Neurons

The role of DNA cytosine methylation, an epigenetic regulator of chromatin structure and function, during normal and pathological brain development and aging remains unclear. Here, we examined by MethyLight PCR the DNA methylation status at 50 loci, encompassing primarily 5′ CpG islands of genes related to CNS growth and development, in temporal neocortex of 125 subjects ranging in age from 17 weeks of gestation to 104 years old. Two psychiatric disease cohorts—defined by chronic neurodegeneration (Alzheimer's) or lack thereof (schizophrenia)—were included. A robust and progressive rise in DNA methylation levels across the lifespan was observed for 8/50 loci (GABRA2, GAD1, HOXA1, NEUROD1, NEUROD2, PGR, STK11, SYK) typically in conjunction with declining levels of the corresponding mRNAs. Another 16 loci were defined by a sharp rise in DNA methylation levels within the first few months or years after birth. Disease-associated changes were limited to 2/50 loci in the Alzheimer's cohort, which appeared to reflect an acceleration of the age-related change in normal brain. Additionally, methylation studies on sorted nuclei provided evidence for bidirectional methylation events in cortical neurons during the transition from childhood to advanced age, as reflected by significant increases at 3, and a decrease at 1 of 10 loci. Furthermore, the DNMT3a de novo DNA methyl-transferase was expressed across all ages, including a subset of neurons residing in layers III and V of the mature cortex. Therefore, DNA methylation is dynamically regulated in the human cerebral cortex throughout the lifespan, involves differentiated neurons, and affects a substantial portion of genes predominantly by an age-related increase

The Public Repository of Xenografts enables discovery and randomized phase II-like trials in mice

More than 90% of drugs with preclinical activity fail in human trials, largely due to insufficient efficacy. We hypothesized that adequately powered trials of patient-derived xenografts (PDX) in mice could efficiently define therapeutic activity across heterogeneous tumors. To address this hypothesis, we established a large, publicly available repository of well-characterized leukemia and lymphoma PDXs that undergo orthotopic engraftment, called the Public Repository of Xenografts (PRoXe). PRoXe includes all de-identified information relevant to the primary specimens and the PDXs derived from them. Using this repository, we demonstrate that large studies of acute leukemia PDXs that mimic human randomized clinical trials can characterize drug efficacy and generate transcriptional, functional, and proteomic biomarkers in both treatment-naive and relapsed/refractory disease

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

Factors Influencing High School Students’ Interest in pSTEM

The transition from high school to college is an important choice point for the pursuit of physical science, technology, engineering, and mathematics (pSTEM) career paths, with students in the United States switching from course selection that is proscribed by state graduation requirements in high school to choosing classes and paths of study more freely in college. Here two studies examine whether social factors identified to inhibit interest in pSTEM within college students similarly affect high school students, and in particular whether these factors could contribute to gender differences in interest in pursuing pSTEM. We find a lower sense of social and ability belonging and lower self-efficacy among female than male high school students pursuing pSTEM classes. In addition, for females but not males, social belonging significantly predicts intentions to continue to pursue pSTEM, highlighting the importance of considering whether low social belonging inhibits intentions to pursue pSTEM for female but not male students. We also find that perceptions of pSTEM fields as requiring innate brilliance more than hard work selectively discourage female students from intending to further pursue pSTEM. Together the studies highlight the potential impact of both subjective self-perceptions and perceptions about pSTEM fields on students’ interest in pSTEM and further identify processes that may selectively dissuade high school females from pursuing pSTEM career paths relative to males