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    A Stochastic Spatiotemporal Model of Rat Ventricular Myocyte Calcium Dynamics Demonstrated Necessary Features for Calcium Wave Propagation
    (MDPI, 2021-11) Hoang-Trong, Tuan Minh; Ullah, Aman; Lederer, William Jonathan; Jafri, Mohsin Saleet
    Calcium (Ca2+) plays a central role in the excitation and contraction of cardiac myocytes. Experi-ments have indicated that calcium release is stochastic and regulated locally suggesting the pos-sibility of spatially heterogeneous calcium levels in the cells. This spatial heterogeneity might be important in mediating different signaling pathways. During more than 50 years of computa-tional cell biology, the computational models have been advanced to incorporate more ionic cur-rents, going from deterministic models to stochastic models. While periodic increases in cyto-plasmic Ca2+ concentration drive cardiac contraction, aberrant Ca2+ release can underly cardiac arrhythmia. However, the study of the spatial role of calcium ions has been limited due to the computational expense of using a three-dimensional stochastic computational model. In this pa-per, we introduce a three-dimensional stochastic computational model for rat ventricular myo-cytes at the whole-cell level that incorporate detailed calcium dynamics, with (1) non-uniform re-lease site placement, (2) non-uniform membrane ionic currents and membrane buffers, (3) sto-chastic calcium-leak dynamics and (4) non-junctional or rogue ryanodine receptors. The model simulates spark-induced spark activation and spark-induced Ca2+ wave initiation and propaga-tion that occur under conditions of calcium overload at the closed-cell condition, but not when Ca2+ levels are normal. This is considered important since the presence of Ca2+ waves contribute to the activation of arrhythmogenic currents.
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    In silico Gene Set and Pathway Enrichment Analyses Highlight Involvement of Ion Transport in Cholinergic Pathways in Autism: Rationale for Nutritional Intervention
    (Frontiers, 2021-04-20) Olson, Audrey; Zhang, Fuquan; Baranova, Ancha; Slavin, Margaret
    Food is the primary human source of choline, an essential precursor to the neurotransmitter acetylcholine, which has a central role in signaling pathways that govern sensorimotor functions. Most Americans do not consume their recommended amount of dietary choline, and populations with neurodevelopmental conditions like autism spectrum disorder (ASD) may be particularly vulnerable to consequences of choline deficiency. This study aimed to identify a relationship between ASD and cholinergic signaling through gene set enrichment analysis and interrogation of existing database evidence to produce a systems biology model. In gene set enrichment analysis, two gene ontologies were identified as overlapping for autism- related and for cholinergic pathways-related functions, both involving ion transport regulation. Subsequent modeling of ion transport intensive cholinergic signaling pathways highlighted the importance of two genes with autism-associated variants: GABBR1, which codes for the gamma aminobutyric acid receptor (GABAB 1), and KCNN2, which codes for calcium-activated, potassium ion transporting SK2 channels responsible for membrane repolarization after cholinergic binding/signal transmission events. Cholinergic signal transmission pathways related to these proteins were examined in the Pathway Studio environment. The ion transport ontological associations indicated feasibility of a dietary choline support as a low-risk therapeutic intervention capable of modulating cholinergic sensory signaling in autism. Further research at the intersection of dietary status and sensory function in autism is warranted.
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    Localization of Free and Bound Metal Species through X-Ray Synchrotron Fluoresence Microscopy in the Rodent Brain and Their Relation to Behavior
    (Brain Sciences, 2019) Neely, Caroline L.C.; Lippi, Stephen L.P.; Lanzirotti, Antonio; Flinn, Jane M.
    Biometals in the brain, such as zinc, copper, and iron, are often discussed in cases of neurological disorders; however, these metals also have important regulatory functions and mediate cell signaling and plasticity. With the use of synchrotron X-ray fluorescence, our lab localized total, both bound and free, levels of zinc, copper, and iron in a cross section of one hemisphere of a rat brain, which also showed differing metal distributions in different regions within the hippocampus, the site in the brain known to be crucial for certain types of memory. This review discusses the several roles of these metals in brain regions with an emphasis on hippocampal cell signaling, based on spatial mapping obtained from X-ray fluorescence microscopy. We also discuss the localization of these metals and emphasize different cell types and receptors in regions with metal accumulation, as well as the potential relationship between this physiology and behavior.
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    Haplotype Analysis of SERPINE1 Gene: Risk for Aneurysmal Subarachnoid Hemorrhage and Clinical Outcomes
    (Molecular Genetics & Genomic Medicine, 2019) Lin, Mingkuan; Griessenauer, Christoph J.; Starke, Robert M.; Tubbs, R. Shane; Shoja, Mohammadali M.; Foreman, Paul M.; Vyas, Nilesh A.; Walters, Beverly C.; Harrigan, Mark R.; Hendrix, Philipp; Fisher, Winfield S.; Pittet, Jean-Francois; Mathru, Mali; Lipsky, Robert H.
    Background: Aneurysmal subarachnoid hemorrhage (aSAH) has high fatality and permanent disability rates due to the severe damage to brain cells and inflammation. The SERPINE1 gene that encodes PAI‐1 for the regulation of tissue plasminogen activator is considered an important therapeutic target for aSAH.Methods: Six SNPs in the SERPINE1 gene (in order of rs2227631, rs1799889, rs6092, rs6090, rs2227684, rs7242) were investigated. Blood samples were geno-typed with Taqman genotyping assays and pyrosequencing. The experiment‐wide statistically significant threshold for single marker analysis was set at p < 0.01 after evaluation of independent markers. Haplotype analysis was performed in Haplo.stats package with permutation tests. Bonferroni correction for multiple comparison in dominant, additive, and recessive model was applied.Results: A total of 146 aSAH patients and 49 control subjects were involved in this study. The rs2227631 G allele is significant (p = 0.01) for aSAH compared to control. In aSAH group, haplotype analysis showed that G5GGGT homozygotes in recessive model were associated with delayed cerebral ischemia (p < 0.01, Odds Ratio = 5.14, 95% CI = 1.45–18.18), clinical vasospasm (p = 0.01, Odds Ratio = 4.58, 95% CI = 1.30–16.13), and longer intensive care unit stay (p = 0.01). By contrast, the G5GGAG carriers were associated with less incidence of cerebral edema (p < 0.01) and higher Glasgow Coma Scale (p < 0.01). The A4GGGT carriers were associated with less incidence of severe hypertension (>140/90) (p < 0.01).Conclusion: The results suggested an important regulatory role of the SERPINE1gene polymorphism in clinical outcomes of aSAH.
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    Investigating Fishing Impacts in Nigerian Coastal Waters For Peer Review Only Using Marine Trophic Index Analyses 
    (Marine and Coastal Fisheries, 2019) Adebola, Tunde M; de Mutsert, Kim
    In Nigerian coastal waters (NCW), fishing has increased steadily over the last seven decades. Artisanal fisheries cover the entire 850‐km length of the coast, where over 1 million fishermen exploit estuarine and oceanic resources up to 40 m deep, and approximately 250 industrial trawlers target fish resources in deeper waters beyond the first 9.26 km (5 nautical miles) from shore. We investigated the hypothesis that growth in fishing effort will increase impacts on coastal fish stocks, as reflected by significant reductions in the mean trophic level (MTL) and maximum mean length of the catch and an increase in the fishing‐in‐balance index. Our analyses are based on a 60‐year time series from 1950 to 2010 (obtained from the Sea Around Us Project; www.seaaroundus.org). Results showed that the impacts of fishing in NCW are high. The sustained increases in landings from the 1970s to the 2000s have resulted in less productive coastal fisheries, a reduction in the MTL of the catch (which might mean reduced biodiversity), a reduction of average size in the fisheries, and the need to expand further into deeper waters to maintain catch levels. This research contributes to fisheries ecology by furthering our understanding of coastal fisheries and their impacts on marine biodiversity.
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    Fully Dense UNet for 2D Sparse Photoacoustic Tomography Artifact Removal
    (Journal of Biomedical and Health Informatics, 2019) Guan, Steven; Khan, Amir A.; Sikdar, Siddartha; Chitnis, Parag V.
    Photoacoustic imaging is an emerging imaging modality that is based upon the photoacoustic effect. In photoacoustic tomography (PAT), the induced acoustic pressure waves are measured by an array of detectors and used to reconstruct an image of the initial pressure distribution. A common challenge faced in PAT is that the measured acoustic waves can only be sparsely sampled. Reconstructing sparsely sampled data using standard methods results in severe artifacts that obscure information within the image. We propose a modified convolutional neural network (CNN) architecture termed Fully Dense UNet (FD-UNet) for removing artifacts from 2D PAT images reconstructed from sparse data and compare the proposed CNN with the standard UNet in terms of reconstructed image quality.
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    The role of native phonology in spontaneous imitation: Evidence from Seoul Korean
    (Journal of the Association of Laboratory Phonology, 2019) Kwon, Harim
    This study investigates the role of phonology in spontaneous imitation in Seoul Korean speakers’ imitation of aspirated stops by comparing the primary and non-primary cues. Seoul Korean aspirated stops are differentiated from stops of other phonation types by at least two distinct acoustic properties, stop VOT and f0 of the post-stop vowel, with the latter being the primary cue. In the imitation experiment, Seoul Korean speakers heard and shadowed model speech that contained aspirated stops manipulated by either raising post-stop f0 or lengthening VOT. Their realization of these properties in /tʰ/, /t/, and /t*/ productions were compared before, during, and after exposure. Although both high f0 and long VOT induced imitative changes in post-shadowing productions, the results revealed that exposure to an enhanced non-primary cue (long VOT) also influences the production of the primary cue for aspirated stops (post-stop f0). However, an enhanced primary cue (high f0) does not have similar effects on the non-primary cue. These results provide evidence that spontaneous imitation is not strictly tied to individual phonetic properties but it is rather phonological in that abstract categories are involved in the process of imitation.
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    40Ar/39Ar and paleomagnetic constraints on the age and areal extent of the Picabo volcanic field: Implications for the Yellowstone hotspot
    (Geosphere, 2019) Anders, Mark H.; DiVenere, Viktor J.; Hemming, Sidney R.; Gombiner, Joel
    The Picabo volcanic field is one of the key silicic volcanic fields in the time-transgressive track of the Yellowstone hotspot. The Picabo volcanic field is also one of the most poorly defined volcanic fields along the track of the Yellowstone hotspot. Determining the age and areal extent of the Picabo volcanic field ignimbrites is one of the primary objectives of this study. In our effort to correlate ignimbrites within the Picabo volcanic field as well as identify those from the neighboring Twin Falls and Heise volcanic fields, we present new petrographic, 40Ar/39Ar, and paleomagnetic data. With these data, we correlated several ignimbrites within the Picabo volcanic field. In some cases, we correlate units previously thought to be in the Picabo volcanic field to older volcanic fields. This includes the Picabo Tuff, which we suggest originates from the Twin Falls volcanic field rather from its namesake volcanic field. The first and best documented major silicic eruption of the volcanic field, the Arbon Valley Tuff, is also the largest ignimbrite in the Picabo volcanic field. There is disagreement as to whether the Arbon Valley Tuff is the result of a single ignimbrite eruption or multiple eruptions. We previously have suggested that the Arbon Valley Tuff is the result of two eruptions, one at 10.41 ± 0.01 Ma and the other at 10.22 ± 0.01 Ma (Anders et al., 2014). Those combining radiometric dates into a single eruption age report ages of 10.2 Ma, 10.27 ± 0.01 Ma, 10.34 ± 0.03 Ma, and 10.44 ± 0.27 Ma. We also suggest the final eruption of the Picabo volcanic field was the tuff of American Falls dated at 7.58 ± 0.02 Ma. Estimates of the location of Picabo volcanic field have been used to mark a major change in the migration rate of the Yellowstone–Snake River Plain silicic volcanic system. Based on our new data, we found only minor changes of the boundaries of the Picabo volcanic field from previous studies. Using the age of the Arbon Valley Tuff (10.41 Ma), we calculated an extension-corrected migration rate of 2.27 ± 0.2 cm/yr between the position of the Picabo volcanic field and that of the Yellowstone volcanic field over the past ~10 m.y. This estimate is close to the extension corrected 2.38 ± 0.21 cm/yr value based on the migration of the hotspot deformation field. These rates are consistent with independent estimates of North American plate velocity over the past 10 m.y. and therefore consistent with a fixed reference frame for the Yellowstone hotspot. These results stand in contrast with several recent models for the evolution of the Yellowstone–Snake River Plain volcanic system.
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    Ups and Downs: Social Media Advocacy of Bipolar Disorder on World Mental Health Day
    (Frontiers in Communication, 2019) Nelson, Allister
    Bipolar disorder is a serious illness that claims hundreds of lives each year. In a watershed movement as the framing of bipolar shifts, the disease is gaining more awareness after the diagnosis of Mariah Carey and advocacy by opinion leaders like Stephen Fry. Social media advocacy is a powerhouse that celebrities with bipolar disorder utilize each World Mental Health Day to reduce stigma and increase awareness of bipolar type 1, which constitutes highs of mania and lows of depression, bipolar type 2, which includes lower hypomania and depressions, alongside the less severe mood swings of cyclothymia. This study collected 160 celebrities' social media posts on Twitter that were shared on World Mental Health Day. It randomly sampled amongst the Tweets for thematic and content analysis to discover valences in positive and negative experiences of bipolar disorder and the framing of bipolar. To study effects of opinion leaders on the public, this random sample of opinion leaders was compared to a cumulative census sample of Twitter posts by the public. The public Tweets were gathered a month afterwards following the mental health hashtags #bipolar and #bipolardisorder. The findings of the study provide guidelines for opinion leaders to craft social media posts to increase positive framing of bipolar disorder via positively valenced, encouraging messages. The study lays out what messages resonate with the general public to reduce bipolar disorder stigma. This establishes a basis for further social media campaigns focused on positive, constructive messages that improve the well-being of bipolar individuals globally. The findings suggest that under Roger's diffusion of innovation theory, opinion leaders diagnosed with bipolar disorder are effectively shifting the dialogue surrounding mental health to one of stigma reduction and acceptance. Mainly positively valenced Tweets were shared about bipolar disorder in the general public Twitter sphere a month after opinion leaders communicated support, comfort and encouragement on World Mental Health Day under Burleson's inferable communication goal guidelines. The study suggests that consistent positive messaging about bipolar shared by opinion leaders will have a lasting positive frame shift toward mental health awareness if this trend continues.
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    Modeling the Tertiary Structure of the Rift Valley Fever Virus L Protein
    (Molecules, 2019) Gogovi, Gideon K.; Almsned, Fahad; Bracci, Nicole; Kehn-Hall, Kylene; Shehu, Amarda; Blaisten-Barojas, Estela
    A tertiary structure governs, to a great extent, the biological activity of a protein in the living cell and is consequently a central focus of numerous studies aiming to shed light on cellular processes central to human health. Here, we aim to elucidate the structure of the Rift Valley fever virus (RVFV) L protein using a combination of in silico techniques. Due to its large size and multiple domains, elucidation of the tertiary structure of the L protein has so far challenged both dry and wet laboratories. In this work, we leverage complementary perspectives and tools from the computational-molecular-biology and bioinformatics domains for constructing, refining, and evaluating several atomistic structural models of the L protein that are physically realistic. All computed models have very flexible termini of about 200 amino acids each, and a high proportion of helical regions. Properties such as potential energy, radius of gyration, hydrodynamics radius, flexibility coefficient, and solvent-accessible surface are reported. Structural characterization of the L protein enables our laboratories to better understand viral replication and transcription via further studies of L protein-mediated protein–protein interactions. While results presented a focus on the RVFV L protein, the following workflow is a more general modeling protocol for discovering the tertiary structure of multidomain proteins consisting of thousands of amino acids.
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    De novo aggregation of Alzheimer’s Aβ25-35 peptides in a lipid bilayer
    (Scientific Reports, 2019) Smith, Amy K.; Klimov, Dmitri K.
    A potential mechanism of cytotoxicity attributed to Alzheimer's Aβ peptides postulates that their aggregation disrupts membrane structure causing uncontrollable permeation of Ca2+ ions. To gain molecular insights into these processes, we have performed all-atom explicit solvent replica exchange with solute tempering molecular dynamics simulations probing aggregation of the naturally occurring Aβ fragment Aβ25-35 within the DMPC lipid bilayer. To compare the impact produced on the bilayer by Aβ25-35 oligomers and monomers, we used as a control our previous simulations, which explored binding of Aβ25-35 monomers to the same bilayer. We found that compared to monomeric species aggregation results in much deeper insertion of Aβ25-35 peptides into the bilayer hydrophobic core causing more pronounced disruption in its structure. Aβ25-35 peptides aggregate by incorporating monomer-like structures with stable C-terminal helix. As a result theAβ25-35 dimer features unusual helix head-to-tail topology supported by a parallel of-registry interface. Such topology afords further growth of an aggregate by recruiting additional peptides. Free energy landscape reveals that inserted dimers represent the dominant equilibrium state augmented by two metastable states associated with surface bound dimers and inserted monomers. Using the free energy landscape we propose the pathway of Aβ25-35 binding, aggregation, and insertion into the lipid bilayer.
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    Maternal stress and adolescent brain structure and function
    (Brain and Behavior, 2019) Niehaus, Claire E.; Chaplin, Tara M.; Goncalves, Stefanie F.; Semelsberger, Robin; Thompson, James C.
    Introduction Adolescence is a time of heightened sensitivity in biological stress systems and the emergence of stress‐related psychopathology. Thus, understanding environmental factors in adolescence that might be associated with adolescents'’ stress systems is important. Maternal stress levels may be involved. However, the relationship between maternal stress and the adolescent brain is unknown. Method The present study examined the association between mothers' self‐reported stress levels and mothers' cortisol stress reactivity and their early adolescents' brain structure and functional activation to stressful negative emotional images. Participants included 66 mothers and their 12‐ to 14‐year old adolescents. Mother's perceived stress and salivary cortisol reactivity to a stressful task were collected. Then, adolescents' brain structure and function were assessed in a magnetic resonance imaging session. Results Functional whole‐brain analyses revealed that mothers' higher reported perceived stress, but not cortisol reactivity, predicted adolescents' higher responses in the medial prefrontal cortex (mPFC) to stressful negative emotional stimuli. There were no statistically significant associations for structural analyses. Conclusions Given the finding of maternal stress reactivity related to adolescent mPFC function—an integral structure related to stress responses—parent stress may play a role in the development of neural stress systems in adolescence, with potential implications for development of psychopathology.
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    Designing Wetlands as an Essential Infrastructural Element for Urban Development in the era of Climate Change
    (Sustainability, 2019) Ahn, Changwoo; Schmidt, Stephanie
    The increasing development of urban infrastructure has led to the significant loss of natural wetlands and their ecosystem services. Many novel urban development projects currently attempt to incorporate environmental sustainability, cross-disciplinary collaboration, and community engagement into the intricate challenges we all face in an era of climate change. This paper aims to communicate several key findings on design elements that can be adopted or incorporated in the design of created wetlands as infrastructural elements. Three major design elements—microtopography, hydrologic connectivity, and planting diversity—are presented, and their relations to restoring ecosystem services of urban wetlands, in particular water and habitat quality, are discussed. These design elements can be easily adopted or incorporated in the planning, designing, and construction stages of urban development. The success of urban infrastructure projects may require both better communication among stakeholders and a great deal of community engagement. The Rain Project, a floating wetland project on an urban college campus, demonstrates the role of interdisciplinary collaboration and community engagement as a model for sustainable stormwater management, a critical part of today’s urban development. Further efforts should be made to advance the science of designing urban wetlands and its communication to transform cultural attitudes toward sustainable urban development.
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    Alveoli, teeth, and tooth loss: Understanding the homology of internal mandibular structures in mysticete cetaceans
    (PLoS ONE, 2017) Peredo, Carlos Mauricio; Pyenson, Nicholas D.; Uhen, Mark D.; Marshall, Christopher D.
    The evolution of filter feeding in baleen whales (Mysticeti) facilitated a wide range of ecological diversity and extreme gigantism. The innovation of filter feeding evolved in a shift from a mineralized upper and lower dentition in stem mysticetes to keratinous baleen plates that hang only from the roof of the mouth in extant species, which are all edentulous as adults. While all extant mysticetes are born with a mandible lacking a specialized feeding structure (i.e., baleen), the bony surface retains small foramina with elongated sulci that often merge together in what has been termed the alveolar gutter. Because mysticete embryos develop tooth buds that resorb in utero, these foramina have been interpreted as homologous to tooth alveoli in other mammals. Here, we test this homology by creating 3D models of the internal mandibular morphology from terrestrial artiodactyls and fossil and extant cetaceans, including stem cetaceans, odontocetes and mysticetes. We demonstrate that dorsal foramina on the mandible communicate with the mandibular canal via smaller canals, which we explain within the context of known mechanical models of bone resorption. We suggest that these dorsal foramina represent distinct branches of the inferior alveolar nerve (or artery), rather than alveoli homologous with those of other mammals. As a functional explanation, we propose that these branches provide sensation to the dorsal margin of the mandible to facilitate placement and occlusion of the baleen plates during filer feeding.
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    Robust Inference after Random Projections via Hellinger Distance for Location-Scale Family
    (Entropy, 2019) Li, Lei; Vidyashankar, Anand N.; Diao, Guoqing; Ahmed, Ejaz
    Big data and streaming data are encountered in a variety of contemporary applications in business and industry. In such cases, it is common to use random projections to reduce the dimension of the data yielding compressed data. These data however possess various anomalies such as heterogeneity, outliers, and round-off errors which are hard to detect due to volume and processing challenges. This paper describes a new robust and efficient methodology, using Hellinger distance, to analyze the compressed data. Using large sample methods and numerical experiments, it is demonstrated that a routine use of robust estimation procedure is feasible. The role of double limits in understanding the efficiency and robustness is brought out, which is of independent interest
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    Methionine Oxidation Changes the Mechanism of Aβ Peptide Binding to the DMPC Bilayer
    (Scientific Reports, 2019) Lockhart, Christopher; Smith, Amy K.; Klimov, Dmitri K.
    Using all-atom explicit solvent replica exchange molecular dynamics simulations with solute tempering, we study the efect of methionine oxidation on Aβ10–40 peptide binding to the zwitterionic DMPC bilayer. By comparing oxidized and reduced peptides, we identifed changes in the binding mechanism caused by this modifcation. First, Met35 oxidation unravels C-terminal helix in the bound peptides. Second, oxidation destabilizes intrapeptide interactions and expands bound peptides. We explain these outcomes by the loss of amphiphilic character of the C-terminal helix due to oxidation. Third, oxidation “polarizes” Aβ binding to the DMPC bilayer by strengthening the interactions of the C-terminus with lipids while largely releasing the rest of the peptide from bilayer. Fourth, in contrast to the wild-type peptide, oxidized Aβ induces signifcantly smaller bilayer thinning and drop in lipid density within the binding footprint. These observations are the consequence of mixing oxidized peptide amino acids with lipids promoted by enhanced Aβ conformational fuctuations. Fifth, methionine oxidation reduces the afnity of Aβ binding to the DMPC bilayer by disrupting favorable intrapeptide interactions upon binding, which ofset the gains from better hydration. Reduced binding afnity of the oxidized Aβ may represent the molecular basis for its reduced cytotoxicity.
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    Alveoli, teeth, and tooth loss: Understanding the homology of internal mandibular structures in mysticete cetaceans
    (PLOS One, 2017) Peredo, Carlos Mauricio; Pyenson, Nicholas D.; Uhen, Mark D.; Marshall, Christopher D.
    The evolution of filter feeding in baleen whales (Mysticeti) facilitated a wide range of ecological diversity and extreme gigantism. The innovation of filter feeding evolved in a shift from a mineralized upper and lower dentition in stem mysticetes to keratinous baleen plates that hang only from the roof of the mouth in extant species, which are all edentulous as adults. While all extant mysticetes are born with a mandible lacking a specialized feeding structure (i.e., baleen), the bony surface retains small foramina with elongated sulci that often merge together in what has been termed the alveolar gutter. Because mysticete embryos develop tooth buds that resorb in utero, these foramina have been interpreted as homologous to tooth alveoli in other mammals. Here, we test this homology by creating 3D models of the internal mandibular morphology from terrestrial artiodactyls and fossil and extant cetaceans, including stem cetaceans, odontocetes and mysticetes. We demonstrate that dorsal foramina on the mandible communicate with the mandibular canal via smaller canals, which we explain within the context of known mechanical models of bone resorption. We suggest that these dorsal foramina represent distinct branches of the inferior alveolar nerve (or artery), rather than alveoli homologous with those of other mammals. As a functional explanation, we propose that these branches provide sensation to the dorsal margin of the mandible to facilitate placement and occlusion of the baleen plates during filer feeding.
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    The Centennial Variation of El Niño Impact on Atlantic Tropical Cyclones
    (Earth Interactions, 2018) Yang, Ruixin; Fairley, Allison S.; Park, Wonsun
    Predicting tropical cyclone (TC) activity becomes more important every year while the understanding of what factors impact them continues to be complicated. El Niño–Southern Oscillation (ENSO) is one of the primary factors impacting the activities in both the Pacific and the Atlantic, but an extensive examination of the fluctuation in this system has yet to be studied in its entirety. This article analyzes the ENSO impacts on the Atlantic tropical cyclone activity during the assessed warm and cold years to show the dominant centennial-scale variation impact. This study looks to plausibly link this variation to the Southern Ocean centennial variability, which is rarely mentioned in any factors affecting the Atlantic tropical cyclone activity. This centennial variability could be used to enhance future work related to predicting tropical cyclones.
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    Job Crafting: Older Workers’ Mechanism for Maintaining Person-Job Fit
    (Frontiers in Psychology, 2017) Wong, Carol M.; Tetrick, Lois E.
    Aging at work is a dynamic process. As individuals age, their motives, abilities and values change as suggested by life-span development theories (Lang and Carstensen, 2002; Kanfer and Ackerman, 2004). Their growth and extrinsic motives weaken while intrinsic motives increase (Kooij et al., 2011), which may result in workers investing their resources in different areas accordingly. However, there is significant individual variability in aging trajectories (Hedge et al., 2006). In addition, the changing nature of work, the evolving job demands, as well as the available opportunities at work may no longer be suitable for older workers, increasing the likelihood of person-job misfit. The potential misfit may, in turn, impact how older workers perceive themselves on the job, which leads to conflicting work identities. With the traditional job redesign approach being a top-down process, it is often difficult for organizations to take individual needs and skills into consideration and tailor jobs for every employee (Berg et al., 2010). Therefore, job crafting, being an individualized process initiated by employees themselves, can be a particularly valuable mechanism for older workers to realign and enhance their demands-abilities and needs-supplies fit. Through job crafting, employees can exert personal agency and make changes to the task, social and cognitive aspects of their jobs with the goal of improving their work experience (Wrzesniewski and Dutton, 2001). Building on the Life Span Theory of Control (Heckhausen and Schulz, 1995), we posit that job crafting, particularly cognitive crafting, will be of increasing value as employees age. Through reframing how they think of their job and choosing to emphasize job features that are personally meaningful, older workers can optimize their resources to proactively redesign their jobs and maintain congruent, positive work identities.
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    Child Care Experiences Among Dual Language Learners in the United States: Analyses of the Early Childhood Longitudinal Study–Birth Cohort
    (AERA Open, 2017) Espinosa, Linda M.; LaForett, Doré R.; Burchinal, Margaret; Winsler, Adam; Tien, Hsiao-Chuan; Peisner-Feinberg, Ellen S.; Castro, Dina C.
    Although quality center-based child care is helpful in promoting school readiness for dual language learners (DLLs), little is known about the nonparental child care that young DLL children experience. DLL status is often confounded with immigrant status, ethnicity, and poverty. Using nationally representative data from the Early Childhood Longitudinal Study–Birth Cohort, we examined child care experiences with repeated cross-sectional analyses at 9, 24, and 52 months for DLL and non-DLL children. After accounting for demographic and contextual factors, we found few differences in the quality and type of child care experienced by DLL children and children who hear only English in the home. Child care experiences were more related to country of origin, ethnicity, or immigrant status than DLL status. Nonparental caregivers were more likely to speak the child’s home language in home-based care than center care. Findings illustrate the importance of distinguishing among DLL status, socioeconomic status, ethnicity, country of origin, and immigrant status when considering the child care experiences of DLLs.