High-throughput, noninvasive field phenotyping has revealed genetic variation in crop morphological, developmental, and agronomic traits, but rapid measurements of the underlying physiological and ...biochemical traits are needed to fully understand genetic variation in plant-environment interactions. This study tested the application of leaf hyperspectral reflectance (λ = 500–2,400 nm) as a high-throughput phenotyping approach for rapid and accurate assessment of leaf photosynthetic and biochemical traits in maize (Zea mays). Leaf traits were measured with standard wet-laboratory and gas-exchange approaches alongside measurements of leaf reflectance. Partial least-squares regression was used to develop a measure of leaf chlorophyll content, nitrogen content, sucrose content, specific leaf area, maximum rate of phosphoenolpyruvate carboxylation, CO₂-saturated rate of photosynthesis, and leaf oxygen radical absorbance capacity from leaf reflectance spectra. Partial least-squares regression models accurately predicted five out of seven traits and were more accurate than previously used simple spectral indices for leaf chlorophyll, nitrogen content, and specific leaf area. Correlations among leaf traits and statistical inferences about differences among genotypes and treatments were similar for measured and modeled data. The hyperspectral reflectance approach to phenotyping was dramatically faster than traditional measurements, enabling over 1,000 rows to be phenotyped during midday hours over just 2 to 4 d, and offers a nondestructive method to accurately assess physiological and biochemical trait responses to environmental stress.
Epithelial-mesenchymal transition (EMT) is a tightly regulated process that is critical for embryogenesis but is abnormally activated during cancer metastasis and recurrence. Here we show that a ...switch in CD44 alternative splicing is required for EMT. Using both in vitro and in vivo systems, we have demonstrated a shift in CD44 expression from variant isoforms (CD44v) to the standard isoform (CD44s) during EMT. This isoform switch to CD44s was essential for cells to undergo EMT and was required for the formation of breast tumors that display EMT characteristics in mice. Mechanistically, the splicing factor epithelial splicing regulatory protein 1 (ESRP1) controlled the CD44 isoform switch and was critical for regulating the EMT phenotype. Additionally, the CD44s isoform activated Akt signaling, providing a mechanistic link to a key pathway that drives EMT. Finally, CD44s expression was upregulated in high-grade human breast tumors and was correlated with the level of the mesenchymal marker N-cadherin in these tumors. Together, our data suggest that regulation of CD44 alternative splicing causally contributes to EMT and breast cancer progression.
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► Genetic and geospatial data complement one another in phylogeography. ► Practical examples to illustrate how these data can be integrated. ► Variety of tools and approaches can be ...applied to many biological systems.
The field of phylogeography continues to grow in terms of power and accessibility. Initially uniting population genetics and phylogenetics, it now spans disciplines as diverse as geology, statistics, climatology, ecology, physiology, and bioinformatics to name a few. One major and recent integration driving the field forward is between “statistical phylogeography” and Geographic Information Systems (GIS) (
Knowles, 2009). Merging genetic and geospatial data, and their associated methodological toolkits, is helping to bring explicit hypothesis testing to the field of phylogeography. Hypotheses derived from one approach can be reciprocally tested with data derived from the other field and the synthesis of these data can help place demographic events in an historical and spatial context, guide genetic sampling, and point to areas for further investigation. Here, we present three practical examples of empirical analysis that integrate statistical genetic and GIS tools to construct and test phylogeographic hypotheses. Insights into the evolutionary mechanisms underlying recent divergences can benefit from simultaneously considering diverse types of information to iteratively test and reformulate hypotheses. Our goal is to provide the reader with an introduction to the variety of available tools and their potential application to typical questions in phylogeography with the hope that integrative methods will be more broadly and commonly applied to other biological systems and data sets.
Sensory hypersensitivities are common and distressing features of Fragile X Syndrome (FXS). While there are many drug interventions that reduce behavioral deficits in Fmr1 mice and efforts to ...translate these preclinical breakthroughs into clinical trials for FXS, evidence-based clinical interventions are almost non-existent potentially due to lack of valid neural biomarkers. Local circuit function in sensory networks is dependent on the dynamic balance of activity in inhibitory/excitatory synapses. Studies are needed to examine the association of electrophysiological alterations in neural systems with sensory and other clinical features of FXS to establish their clinical relevance. Adolescents and adults with FXS (
= 38, Mean age = 25.5, std = 10.1; 13 females) and age matched typically developing controls (
= 40, Mean age = 27.7, std = 12.1; 17 females) completed auditory chirp and auditory habituation tasks while undergoing dense array electroencephalography (EEG). Amplitude, latency, and percent change (habituation) in N1 and P2 event-related potential (ERP) components were characterized for the habituation task; time-frequency calculations using Morlet wavelets characterized phase-locking and single trial power for the habituation and chirp tasks. FXS patients showed increased amplitude but some evidence for reduced habituation of the N1 ERP, and reduced phase-locking in the low and high gamma frequency range and increased low gamma power to the chirp stimulus. FXS showed increased theta power in both tasks. While the habituation finding was weaker than previously found, the remaining findings replicate our previous work in a new sample of patients with FXS. Females showed less deficit in the chirp task but not the habituation task. Abnormal increases in gamma power were related to more severe behavioral and psychiatric features as well as reductions in neurocognitive abilities. Replicating electrophysiological deficits in a new group of patients using different EEG equipment at a new data collection site with differing levels of environmental noise that were robust to data processing techniques utilizing multiple researchers, indicates a potential for scalability to multi-site clinical trials. Given the robust replicability, relevance to clinical measures, and preclinical evidence for sensitivity of these EEG measures to pharmacological intervention, the observed abnormalities may provide novel translational markers of target engagement and potentially outcome measures in large-scale studies evaluating new treatments targeting neural hyperexcitability in FXS.
Enterovirus D68 (EV-D68) has historically been associated with respiratory illnesses. However, in the summers of 2014 and 2016, EV-D68 outbreaks coincided with a spike in polio-like acute flaccid ...myelitis/paralysis (AFM/AFP) cases. This raised concerns that EV-D68 could be the causative agent of AFM during these recent outbreaks. To assess the potential neurotropism of EV-D68, we utilized the neuroblastoma-derived neuronal cell line SH-SY5Y as a cell culture model to determine if differential infection is observed for different EV-D68 strains. In contrast to HeLa and A549 cells, which support viral infection of all EV-D68 strains tested, SH-SY5Y cells only supported infection by a subset of contemporary EV-D68 strains, including isolates from the 2014 outbreak. Viral replication and infectivity in SH-SY5Y were assessed using multiple assays: virus production, cytopathic effects, cellular ATP release, and VP1 capsid protein production. Similar differential neurotropism was also observed in differentiated SH-SY5Y cells, primary human neuron cultures, and a mouse paralysis model. Using the SH-SY5Y cell culture model, we determined that barriers to viral binding and entry were at least partly responsible for the differential infectivity phenotype. Transfection of genomic RNA into SH-SY5Y generated virions for all EV-D68 isolates, but only a single round of replication was observed from strains that could not directly infect SH-SY5Y. In addition to supporting virus replication and other functional studies, this cell culture model may help identify the signatures of virulence to confirm epidemiological associations between EV-D68 strains and AFM and allow for the rapid identification and characterization of emerging neurotropic strains.
Since the EV-D68 outbreak during the summer of 2014, evidence of a causal link to a type of limb paralysis (AFM) has been mounting. In this article, we describe a neuronal cell culture model (SH-SY5Y cells) in which a subset of contemporary 2014 outbreak strains of EV-D68 show infectivity in neuronal cells, or neurotropism. We confirmed the difference in neurotropism
using primary human neuron cell cultures and
with a mouse paralysis model. Using the SH-SY5Y cell model, we determined that a barrier to viral entry is at least partly responsible for neurotropism. SH-SY5Y cells may be useful in determining if specific EV-D68 genetic determinants are associated with neuropathogenesis, and replication in this cell line could be used as rapid screening tool for identification of neurotropic EV-D68 strains. This may assist with better understanding of pathogenesis and epidemiology and with the development of potential therapies.
Highlights • DNA methylation in the oxytocin receptor ( OXTR ) gene was associated with postpartum depression. • PPD and early life abuse interacted to influence OXTR DNA methylation at an ERE ...proximal site. • Consistent replication was observed in a gene expression cohort and a large population based sample. • OXTR methylation was associated with antenatal serum estradiol levels. • Estradiol interacted with OXTR methylation to influence allopregnanolone: progesterone ratios.
In an interview, Toni Morrison explains her choice to set the novel Home (2012) in 1950s America; often thought of as a "golden age," Morrison asserts, "I think we forgot what was really going on in ...the 1950s," a comment which evokes the dual notions of state—that is, national and psychological—at work in national and cultural memory. In this vein, using Donald E. Pease's theoretical discussion of state fantasy from The New American Exceptionalism (2009) as a point of departure, this article situates close readings of violence in Home within philosophical discussions of "bare life" and "ungrievability" as advanced by Giorgio Agamben and Judith Butler, respectively, and unites these with historical research on eugenic sterilization practices in the US to explore various destructions of life perpetrated within the legitimating context of American exceptionalism domestically and internationally. Finally, through analysis of various sites that exist at a remove from the dominant exceptionalist landscape such as basements, the jazz bar, burial plots, and the community of Lotus, the essay explores alternative figurations to nation and community that Home presents.
Purpose: This study examined the frequency of code-switching by Spanish-English-speaking children as a function of language proficiency in each language and diagnosis (developmental language disorder ...DLD or typical language development TLD). Method: Sixty-two Spanish-English-speaking children, 5-7 years of age, participated in this study (24 with DLD and 38 with TLD). Language samples were used to determine the level of language proficiency in each language as a continuum of performance. Correlational analyses were conducted to evaluate the relationship between Spanish and English language proficiency and the frequency of code-switching considering the total number of code-switched words, intrasentential code-switching (i.e., number of sentences/C-units with code-switched parts), and intersentential code-switching (i.e., code-switched sentences/C-units). Negative binomial and zero-inflated Poisson regressions were conducted to evaluate whether the frequency of code-switched words, code-switched parts, and code-switched sentences is different across children with DLD and their peers with TLD, controlling for Spanish and English proficiency. Results: When Spanish was the target language, lower proficiency in Spanish was associated with higher frequency of code-switches to English for the group with DLD, but not for their peers with TLD who code-switched to English regardless of their Spanish and English proficiency. There were no statistically significant effects of diagnosis on the frequency of code-switches. Conclusion: Results indicate that code-switching occurs similarly across children with DLD and their peers with TLD; therefore, the frequency and type of code-switches should not be used as an indicator of DLD.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
Purpose
The sensitivity of wildland plants to temperature can be directly measured using experimental manipulations of temperature in situ. We show that soil surface temperature and plant density ...(per square meter) have a significant impact on the germination, growth, and phenology of
Bromus tectorum
L., cheatgrass, a short-statured invasive winter-annual grass, and assess a new experimental temperature manipulation method: the application of black and white gravel to warm and cool the soil surface.
Methods
We monitored height, seed production, and phenological responses of cheatgrass, seeded into colored gravel at low and high densities at two sites in the western USA: Boise, ID and Cheyenne, WY. Soil surface temperature and volumetric water content were measured to assess treatment effects on soil surface microclimate.
Results
Black gravel increased mean temperatures of the surface soil by 1.6 and 2.6 °C compared to white gravel in Cheyenne and Boise, respectively, causing 21–24 more days with soil temperatures > 0 °C, earlier cheatgrass germination, and up to 2.8-fold increases in cheatgrass height. Higher seeding density of cheatgrass led to 1.4-fold taller plants on black gravel plots at both sites, but not white gravel at the Boise site, indicating a possible thermal benefit or reduction of water demand due to plant clustering in warmer treatments.
Conclusions
Manipulating soil-surface albedo altered the soil microclimate and thus growth and phenology of cheatgrass, whose life history and growth form confer a strong dependency on soil-surface conditions.
The White House Task Force on Childhood Obesity has set a goal of increasing walking and biking to school by 50% within 5 years. Meeting the goal requires a detailed understanding of the current ...patterns of school travel.
To document nationally representative estimates of the amount of school travel and the modes used to access school in 2009 and compare these levels with 1969, 1995, and 2001.
The National Household Travel Survey collected data on the travel patterns of 150,147 households in 2008 and 2009. Analyses, conducted in 2010, documented the time, vehicle miles traveled, and modes used by American students to reach school. A binary logit model assessed the influence of trip, child, and household characteristics on the decision to walk to school.
In 2009, 12.7% of K-8 students usually walked or biked to school compared with 47.7% in 1969. Rates of walking and biking to school were higher on the trip home from school in each survey year. During the morning peak period, school travel accounted for 5%-7% of vehicle miles traveled in 2009 and 10%-14% of all private vehicles on the road.
There have been sharp increases in driving children to school since 1969 and corresponding decreases in walking to school. This increase is particularly evident in the number of vehicle trips generated by parents dropping children at school and teens driving themselves. The NHTS survey provides a unique opportunity to monitor these trends in the future.
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