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α- and β-neurexins are extensively alternatively spliced, presynaptic cell-adhesion molecules that are thought to organize synapse assembly. However, recent data revealed that, in the hippocampus in vivo, the deletion of one neurexin isoform, Nrxn2, surprisingly increased excitatory synapse numbers and enhanced their presynaptic release probability, suggesting that Nrxn2 restricts, instead of enabling, synapse assembly. To delineate the synaptic function and mechanism of action of Nrxn2, we examined cultured hippocampal neurons as a reduced system. In heterologous synapse formation assays, different alternatively spliced Nrxn2β isoforms robustly promoted synapse assembly similar to Nrxn1β and Nrxn3β, consistent with a general synaptogenic function of neurexins. Deletion of Nrxn2 from cultured hippocampal neurons, however, caused a significant increase in synapse density and release probability, replicating the in vivo data that suggested a synapse-restricting function. Rescue experiments revealed that two of the four Nrxn2β splice variants (Nrxn2β-SS4+/SS5- and Nrxn2β-SS4+/SS5+) reversed the increase in synapse density in Nrxn2-deficient neurons, whereas only one of the four Nrxn2β splice variants (Nrxn2β-SS4+/SS5+) normalized the increase in release probability in Nrxn2-deficient neurons. Thus, a subset of Nrxn2 splice variants restricts synapse numbers and restrains their release probability in cultured neurons.

The "Journal of Family & Consumer Sciences" ("JFCS") reflects the broad scope and reach of the family and consumer sciences (FCS) discipline through its inclusion of Scholarship, Practice, Strategies, Features, Reflections, and other articles that span content areas, settings, populations, issues, and methodologies. Recently, several "JFCS" Features have addressed the importance of disciplinary positioning for future relevance and impact (Carroll et al., 2017; Hall, 2015; McGregor et al., 2015). A new decade provides an opportunity to reflect on recent disciplinary trends showcased in "JFCS," including the topics that appear most frequently and how FCS professionals are addressing them. The purpose of this paper is to enable such reflection by presenting an overview of "JFCS" submissions over the past 10 years (2009--2018). In this paper, the overview of "JFCS" submissions is discussed in the context of the FCS Body of Knowledge (FCS-BOK). Over the past 20 years, the FCS-BOK has provided a framework for the discipline, indicating what is important (Roubanis, 2013), guiding research (Nickols et al., 2009), and helping universities mold committed FCS professionals (Reibolt et al., 2016; Walker et al., 2015). It consists of three categories: (a) Core Concepts (basic human needs, community vitality, individual well-being, and family strength), (b) Integrative Elements (human eco-system and life course development), and (c) Cross-Cutting Themes (capacity building, global interdependence, resource development, appropriate use of technology, and wellness) (Lee et al., 2015; Nickols et al., 2009). Review of "JFCS" disciplinary trends against the FCS-BOK would provide an opportunity to identify those elements in the FCS-BOK that have been well-covered (or not) in the past decade; and would suggest the continued relevance of the FCS-BOK in shaping professional work and dissemination.

Even though the endocrine-disrupting potential of perfluorooctanoic acid (PFOA) is well known, the mechanisms underlying its cellular and epigenetic toxicity at the critical stage of hypothalamic development are poorly understood. This is why we studied its effects on the embryonic mouse hypothalamic cell line N46 (mHypoE-N46) with a hope to shed more light on the mechanisms through which PFOA causes embryonic hypothalamic cell damage. To do that, we studied cell viability, global DNA methylation, and gene expression in cells exposed to PFOA. As the PFOA dose increased, cell viability decreased, while global DNA methylation increased. PFOA also significantly altered the expression of genes related to the apoptosis and cell cycle, neurotrophic genes, and the Tet, Dnmt, and Mecp2 genes. Our findings suggest that exposure to PFOA affects cell survival through the reprogramming of embryonic hypothalamic DNA methylation patterns and altering cell homeostasis genes. DNA methylation and changes in the Mecp2 gene expression induced by PFOA also imply wider ramifications, as they alter genes of other major mechanisms of the embryonic hypothalamus. Our study may therefore serve as a good starting point for further research into the mechanisms of PFOA effect of hypothalamic development.

Westinghouse is developing a lead-cooled fast reactor (LFR) as its next-generation utility-scale nuclear power plant. To support its development, Westinghouse and its partners are building 10 test facilities to demonstrate key LFR phenomena, materials, and components in liquid lead. These test infrastructures are distributed across several institutions, and this paper focuses on those located within Westinghouse. It describes three state-of-the-art test rigs being installed in the Westinghouse facility in Springfields, United Kingdom, to test materials in liquid lead and to investigate key LFR phenomena, which will also be used to validate modeling and simulation tools. These facilities address material corrosion/erosion testing (MELECOR), lead freezing and under-lead viewing testing (LEFREEZ), and primary heat exchanger failure testing (LEWIN). This paper also describes the first liquid-lead test system to become operational at Westinghouse at the company's site in Churchill, Pennsylvania, i.e., a test rig named HELMET to conduct tensile tests in a molten-lead environment to investigate the potential susceptibility of LFR candidate materials to liquid-metal embrittlement. [ABSTRACT FROM AUTHOR]

What is the impact of housing adequacy on recent home modification, controlling for demographics and housing characteristics? This study examined home modifications of households with a member aged 65 or older, focusing on relationships between selected demographic and housing variables and home modification. Binary logistic regression analysis was used on a sample of 6,627 homeowners from the newly released 2019 American Housing Survey (AHS) dataset. This analysis of the 2019 AHS data is important because of its pre-COVID pandemic era perspective in terms of home modifications and older adults aging in place. Results showed that recent housing modifications were significantly affected by select demographic and housing factors. [ABSTRACT FROM AUTHOR]

This paper presents an assessment aimed at evaluating primary heat exchanger (PHE) failure of the Westinghouse Electric Company Lead-cooled Fast Reactor (LFR) and at designing a facility for testing phenomena involved in such failure. The system thermal-hydraulic code RELAP5/MOD3.3 was used to develop a transient analysis simulation at reactor scale. Because of RELAP5/MOD3.3's inability to mix working fluids, the steam injection effect was evaluated using the SIMMER-III code. The limits and strengths of both codes are highlighted throughout the paper. The reactor-scale steady-state results are in good agreement with the nominal operating condition. The transient results show that lead pool surface level variation and primary system pressurization during the PHE failure event are limited. The PHE failure testing facility was characterized, and a preliminary layout was developed. A separate-effects transient inside the vessel was analyzed with SIMMER-III and RELAP5/MOD3.3 runs. The simulation outcomes have provided useful data to inform subsequent design stages for the test facility. Different configurations of the facility have been assessed, highlighting the strengths and weaknesses of each design. The most important issue was identified to be lead pool swelling, reaching the vessel's lid and blocking the pressure relief vent. This poses a safety hazard that must be addressed and has been raised for resolution in subsequent design stages. The so-called V4 configuration is suggested as a starting point for further improvement of the facility. Furthermore, a smaller failure opening and lower lead level in the vessel are suggested. [ABSTRACT FROM AUTHOR]

Neuroligins are postsynaptic cell-adhesion molecules that bind presynaptic neurexins and are genetically linked to autism. Neuroligins are proposed to organize synaptogenesis and/or synaptic transmission, but no systematic analysis of neuroligins in a defined circuit is available. Here, we show that conditional deletion of all neuroligins in cerebellar Purkinje cells caused loss of distal climbing-fiber synapses and weakened climbing-fiber but not parallel-fiber synapses, consistent with alternative use of neuroligins and cerebellins as neurexin ligands for the excitatory climbing-fiber versus parallel-fiber synapses. Moreover, deletion of neuroligins increased the size of inhibitory basket/stellate-cell synapses but simultaneously severely impaired their function. Multiple neuroligin isoforms differentially contributed to climbing-fiber and basket/stellate-cell synapse functions, such that inhibitory synapse-specific neuroligin-2 was unexpectedly essential for maintaining normal climbing-fiber synapse numbers. Using systematic analyses of all neuroligins in a defined neural circuit, our data thus show that neuroligins differentially contribute to various Purkinje-cell synapses in the cerebellum in vivo.

α- and β-neurexins are presynaptic cell-adhesion molecules implicated in autism and schizophrenia. We find that, although β-neurexins are expressed at much lower levels than α-neurexins, conditional knockout of β-neurexins with continued expression of α-neurexins dramatically decreased neurotransmitter release at excitatory synapses in cultured cortical neurons. The β-neurexin knockout phenotype was attenuated by CB1-receptor inhibition, which blocks presynaptic endocannabinoid signaling, or by 2-arachidonoylglycerol synthesis inhibition, which impairs postsynaptic endocannabinoid release. In synapses formed by CA1-region pyramidal neurons onto burst-firing subiculum neurons, presynaptic in vivo knockout of β-neurexins aggravated endocannabinoid-mediated inhibition of synaptic transmission and blocked LTP; presynaptic CB1-receptor antagonists or postsynaptic 2-arachidonoylglycerol synthesis inhibition again reversed this block. Moreover, conditional knockout of β-neurexins in CA1-region neurons impaired contextual fear memories. Thus, our data suggest that presynaptic β-neurexins control synaptic strength in excitatory synapses by regulating postsynaptic 2-arachidonoylglycerol synthesis, revealing an unexpected role for β-neurexins in the endocannabinoid-dependent regulation of neural circuits.

Breakfast is the most important meal of the day. The purpose of this study is to examine breakfast-eating behaviors of Historically Black College and University (HBCU) students in conjunction with their breakfast awareness and eating habit satisfaction. A self-administered survey was distributed in fall semester 2016 (N 289 students). Results show that 72% of students at a HBCU who participated in the survey were only moderately satisfied with their eating habits. Breakfast skippers were more likely to be African American students. Opportunities exist for family and consumer sciences (FCS) educators to develop intervention programs about putting knowledge into practice in order to improve African American students' health and well-being through breakfast eating.