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Global respiratory balance is maintained by photosynthetic organisms, yet the importance of this contribution is not commensurate with our understanding of light-driven metabolic processes. Meanwhile, there has been a increase in the desire to engineer phototrophic microorganisms. Excessive demands by modern society have been depleting nature's resources over the past centuries. Exploring and developing new sustainable resources to counter increasing consumption has therefore been the focus of research efforts in the academic and private sectors. The emphasis has partly been on using phototrophic organisms that fix carbon dioxide by utilizing light energy to produce energy-dense products. Recent efforts to characterize metabolic capabilities of photosynthetic species as well as engineer attractive candidates require a framework for discovery, data analysis and reconfiguring of existing metabolic networks. The systems biology approach of constraint-based reconstruction and analysis coupled with flux balance analysis has a proven record of contextualizing organism specific information and characterizing cellular metabolism. However, a persistent challenge in the modeling of photoautotrophy has been a mechanistic incorporation of light uptake. As the light environment dictates cell physiology, such as growth rate, biomass composition and metabolic pathway usage, constraining photon flux is a prerequisite for biologically accurate results. Here we describe efforts to address this challenge and the resulting insights into photoautotrphic biology. First, a proper accounting of light uptake and shading coupled with a high-quality genome-scale model of the cyanobacteriaSynechococcus elongatus sp. PCC7942 resulted in accurate growth and flux predictions. Additionally,we concluded despite an incomplete TCA cycle in the organism studied, there was no impact to fitness due to the metabolic network configuration. Next, in an attempt to extend the methodology to eukaryotic microalgae, we generated a genome-scale model of the diatom Phaeodactylum tricornutum. The systems biology perspective elucidated metabolic capabilities in this organism conferred by its unique phylogeny. Applying an improved set of photophysiology constraints, we simulated circadian dynamics and characterized photoprotective mechanisms resulting from the previously elucidated metabolic capabilities; highlighting the importance of the broader metabolic network in dissipating excess light energy. Finally, photophysiology constraints coupled to chlorophyll fluorescence measurements and genome-scale modeling enabled a comparative analysis of light environment acclimation across the phototrophic clades cyanobacteria, green algae and diatoms and quantified the fraction of excess light energy absorbed by the cells and its metabolic fate. Overall, coupling mechanistic constraints on photophysiology with genome-scale modeling accurately characterized the cellular response to the light environment. This work is relevant to understanding species-specific metabolic capabilities and adaptations of interest to biological and bioengineering communities.

Recently discovered amber-preserved fossil Cicadellidae exhibit combinations of morphological traits not observed in the modern fauna and have the potential to shed new light on the evolution of this highly diverse family. To place the fossils explicitly within a phylogenetic context, representatives of five extinct genera from Cretaceous Myanmar amber, and one from Eocene Baltic amber were incorporated into a matrix comprising 229 discrete morphological characters and representatives of all modern subfamilies. Phylogenetic analyses yielded well resolved and largely congruent estimates that support the monophyly of most previously recognized cicadellid subfamilies and indicate that the treehoppers are derived from a lineage of Cicadellidae. Instability in the morphology-based phylogenies is mainly confined to deep internal splits that received low branch support in one or more analyses and also were not consistently resolved by recent phylogenomic analyses. Placement of fossil taxa is mostly stable across analyses. Three new Cretaceous leafhopper genera, Burmotettix gen. nov., Kachinella gen nov., and Viraktamathus gen. nov., consistently form a monophyletic group distinct from extant leafhopper subfamilies and are placed in Burmotettiginae subfam. nov. Extinct Cretaceous fossils previously placed in Ledrinae and Signoretiinae are recovered as sister to modern representatives of these groups. Eomegophthalmus Dietrich and Gonçalves from Baltic amber consistently groups with a lineage comprising treehoppers, Megophthalminae, Ulopinae, and Eurymelinae but its position is unstable. Overall, the morphology-based phylogenetic estimates agree with recent phylogenies based on molecular data alone suggesting that morphological traits recently used to diagnose subfamilies are generally informative of phylogenetic relationships within this group.

PURPOSE: Down syndrome (DS) is caused by trisomy 21 (Ts21) and results in skeletal deficits including shortened stature, low bone mineral density and a predisposition to early onset osteoporosis. Ts21 causes significant alterations in skeletal development, morphology of the appendicular skeleton, bone homeostasis, age-related bone loss, and bone strength. However, the genetic or cellular origins of DS skeletal phenotypes remain unclear. RECENT FINDINGS: New studies reveal a sexual dimorphism in characteristics and onset of skeletal deficits that differ between DS and typically developing individuals. Age-related bone loss occurs earlier in the DS as compared to general population. SUMMARY: Perturbations of DS skeletal quality arise from alterations in cellular and molecular pathways affected by the overexpression of trisomic genes. Sex-specific alterations occur in critical developmental pathways that disrupt bone accrual, remodeling, and homeostasis and are compounded by aging, resulting in increased risks for osteopenia, osteoporosis and fracture in individuals with DS.

Objective Recent research suggests that many American voters use candidate accents as an evaluative heuristic. We build on this research by examining whether this effect is conditional on the partisan positions of the candidate and across participant party identification. Methods We designed an experiment using actors to record candidate stump speeches, manipulating the accent of the candidate and the partisan issue position of the candidate. Results Democrats and Republicans in our sample were more likely to believe candidates with southern accents were Republican as opposed Democrat, and were also more likely to negatively evaluate candidates with a southern accent. This was true in both instances regardless of whether the candidate espoused a typical Democratic or Republican issue position. Democrats’ judgments of candidates with southern accents, though, were harsher than those of Republicans and, again, this was the case across the partisan positioning of the candidate. Finally, both Democrats and Republicans in our pool were less likely to say they would vote for the candidate with a southern accent regardless of the partisan position of the candidate. Conclusion Our results confirm that accent is a heuristic and add nuance to our understanding of how partisanship shapes this effect.

Trisomy 21 (Ts21) causes alterations in skeletal development resulting in decreased bone mass, shortened stature and weaker bones in individuals with Down syndrome (DS). There is a sexual dimorphism in bone mineral density (BMD) deficits associated with DS with males displaying earlier deficits than females. The relationships between causative trisomic genes, cellular mechanisms, and influence of sex in DS skeletal abnormalities remain unknown. One hypothesis is that the low bone turnover phenotype observed in DS results from attenuated osteoblast function, contributing to impaired trabecular architecture, altered cortical geometry, and decreased mineralization. DYRK1A, found in three copies in humans with DS, Ts65Dn, and Dp1Tyb DS model mice, has been implicated in the development of postnatal skeletal phenotypes associated with DS. Reduced copy number of Dyrk1a to euploid levels from conception in an otherwise trisomic Ts65Dn mice resulted in a rescue of appendicular bone deficits, suggesting DYRK1A contributes to skeletal development and homeostasis. We hypothesized that reduction of Dyrk1a copy number in trisomic osteoblasts would improve cellular function and resultant skeletal structural anomalies in trisomic mice. Female mice with a floxed Dyrk1a gene (Ts65Dn,Dyrk1afl/wt) were mated with male Osx-Cre+ (expressed in osteoblasts beginning around E13.5) mice, resulting in reduced Dyrk1a copy number in mature osteoblasts in Ts65Dn,Dyrk1a+/+/Osx-Cre P42 male and female trisomic and euploid mice, compared with littermate controls. Male and female Ts65Dn,Dyrk1a+/+/+ (3 copies of DYRK1A in osteoblasts) and Ts65Dn,Dyrk1a+/+/Osx-Cre (2 copies of Dyrk1a in osteoblasts) displayed similar defects in both trabecular architecture and cortical geometry, with no improvements with reduced Dyrk1a in osteoblasts. This suggests that trisomic DYRK1A does not affect osteoblast function in a cell-autonomous manner at or before P42. Although male Dp1Tyb and Ts65Dn mice exhibit similar skeletal deficits at P42 in both trabecular and cortical bone compartments between euploid and trisomic mice, female Ts65Dn mice exhibit significant cortical and trabecular deficits at P42, in contrast to an absence of genotype effect in female Dp1Tyb mice in trabecular bone. Taken together, these data suggest skeletal deficits in DS mouse models and are sex and age dependent, and influenced by strain effects, but are not solely caused by the overexpression of Dyrk1a in osteoblasts. Identifying molecular and cellular mechanisms, disrupted by gene dosage imbalance, that are involved in the development of skeletal phenotypes associated with DS could help to design therapies to rescue skeletal deficiencies seen in DS.

The Zhangpu biota provides a new insight into biodiversity redistribution during the Mid-Miocene Climatic Optimum., During the Mid-Miocene Climatic Optimum [MMCO, ~14 to 17 million years (Ma) ago], global temperatures were similar to predicted temperatures for the coming century. Limited megathermal paleoclimatic and fossil data are known from this period, despite its potential as an analog for future climate conditions. Here, we report a rich middle Miocene rainforest biome, the Zhangpu biota (~14.7 Ma ago), based on material preserved in amber and associated sedimentary rocks from southeastern China. The record shows that the mid-Miocene rainforest reached at least 24.2°N and was more widespread than previously estimated. Our results not only highlight the role of tropical rainforests acting as evolutionary museums for biodiversity at the generic level but also suggest that the MMCO probably strongly shaped the East Asian biota via the northern expansion of the megathermal rainforest biome. The Zhangpu biota provides an ideal snapshot for biodiversity redistribution during global warming.

Two new extinct fossil cicadellid taxa from Eocene Baltic amber, representing the subfamily Eurymelinae (sensu lato), are described and illustrated, and their relationships to modern leafhoppers are discussed. Eoidiocerus emarginatus gen. and sp. n. is the oldest known representative of the tribe Idiocerini. The new genus resembles some modern Afrotropical and Indomalayan idiocerine genera but differs in having the gena relatively narrow. Archipedionis obscurus gen. and sp. n., is the first well-preserved fossil representative of Macropsini to be described in detail. Previous reports of this tribe from Baltic amber, while credible, included too little morphological information to assess their relationships. Additional comparative notes are provided for previously described fossil taxa belonging to Idiocerini and Macropsini from the Oligocene of Germany. The new combinations Oncopsis sepultus sepultus (Statz, 1950), comb. n. and Oncopsis sepultus austerus (Statz, 1950), comb. n. are proposed for taxa previously included in Bythoscopus Germar. The previously unplaced cicadellid fossil taxon Priscacutius denticulatus Poinar & Brown, 2018 from mid-Cretaceous Myanmar amber is newly placed in subfamily Signoretiinae, tribe Phlogisini, and represents the oldest known member of this subfamily, the only one known from the fossil record and only the second modern cicadellid subfamily confirmed by direct fossil evidence to have been present during the Cretaceous period.

Down syndrome (DS) is caused by three copies of human chromosome 21 (Hsa21) and results in phenotypes including intellectual disability and skeletal deficits. Ts65Dn mice have three copies of ~50% of the genes homologous to Hsa21 and display phenotypes associated with DS, including cognitive deficits and skeletal abnormalities. DYRK1A is found in three copies in humans with Trisomy 21 and in Ts65Dn mice, and is involved in a number of critical pathways including neurological development and osteoclastogenesis. Epigallocatechin-3-gallate (EGCG), the main polyphenol in green tea, inhibits Dyrk1a activity. We have previously shown that EGCG treatment (~10mg/kg/day) improves skeletal abnormalities in Ts65Dn mice, yet the same dose, as well as ~20mg/kg/day did not rescue deficits in the Morris water maze spatial learning task (MWM), novel object recognition (NOR) or balance beam task (BB). In contrast, a recent study reported that an EGCG-containing supplement with a dose of 2–3 mg per day (~40–60mg/kg/day) improved hippocampal-dependent task deficits in Ts65Dn mice. The current study investigated if an EGCG dosage similar to that study would yield similar improvements in either cognitive or skeletal deficits. Ts65Dn mice and euploid littermates were given EGCG [0.4 mg/mL] or a water control, with treatments yielding average daily intakes of ~50 mg/kg/day EGCG, and tested on the multivariate concentric square field (MCSF)—which assesses activity, exploratory behavior, risk assessment, risk taking, and shelter seeking—and NOR, BB, and MWM. EGCG treatment failed to improve cognitive deficits; EGCG also produced several detrimental effects on skeleton in both genotypes. In a refined HPLC-based assay, its first application in Ts65Dn mice, EGCG treatment significantly reduced kinase activity in femora but not in the cerebral cortex, cerebellum, or hippocampus. Counter to expectation, 9-week-old Ts65Dn mice exhibited a decrease in Dyrk1a protein levels in Western blot analysis in the cerebellum. The lack of beneficial therapeutic behavioral effects and potentially detrimental skeletal effects of EGCG found in Ts65Dn mice emphasize the importance of identifying dosages of EGCG that reliably improve DS phenotypes and linking those effects to actions of EGCG (or EGCG-containing supplements) in specific targets in brain and bone.

A new genus and species of pygmy grasshopper (Orthoptera: Tetrigidae) is described from Eocene Baltic amber. Danatettix hoffeinsorum gen. et sp. nov. is assigned to the subfamily Batrachideinae based on antennae with more than 19 antennomeres, sulcate mesofemora, and rectangular paranota. This species is readily distinguished from other batrachideines by a markedly produced vertex, pronotum with divergent internal and external lateral carinae, and highly setiferous female lateral basivalvular sclerite with scabrose integument. The morphology of Danatettix suggests placement within the here defined Tettigidea genus group (comprising Eutettigidea Hancock, 1914, Paurotarsus Hancock, 1900, and Tettigidea Scudder, 1862) and suggests that the latter had diverged from the new Scaria genus group (comprising Eotetrix Gorochov, 2012, Rehnidium Grant, 1956 and Scaria Bolívar, 1887) by the Early Eocene.

Thirty-one species of Nearctic Perlesta Banks, 1906 (Plecoptera: Perlidae) are recognized. A new species is described from western Arkansas and eastern Oklahoma, USA, Perlestasublobata South & DeWalt, sp. nov., from the adult male, adult female, and egg. Perlestasublobata males are differentiated from other congeners by a combination of a prominent ventral caecum and a distinct dorsal extension of the lateral sclerites of the aedeagus. A preliminary molecular phylogenetic hypothesis is proposed for Perlesta based on 17 congeners and three outgroup taxa using partial mitochondrial cytochrome c oxidase subunit I sequence data. Illustrations, stereomicroscope images, and scanning electron micrographs support the description and comparison to other Perlesta.

A new genus and species of Elcanidae (Insecta: Orthoptera) is described from mid-Cretaceous Burmese amber. Elcanonympha diana gen. et sp. nov. is known from a single, complete nymph and is distinguished from other elcanids by the pronotum cut by a single transverse sulcus, the dorsal margin of the metafemoral genicula with a row of prominent apical denticles, and the distal third of the metabasitarsus bearing a row of apically directed scale-like spines on the ventral surface.

In this paper, we develop computationally efficient techniques to calculate statistics used in wind farm optimization with the goal of enabling the use of higher-fidelity models and larger wind farm optimization problems. We apply these techniques to maximize the annual energy production (AEP) of a wind farm by optimizing the position of the individual wind turbines. The AEP (a statistic) is the expected power produced by the wind farm over a period of 1 year subject to uncertainties in the wind conditions (wind direction and wind speed) that are described with empirically determined probability distributions. To compute the AEP of the wind farm, we use a wake model to simulate the power at different input conditions composed of wind direction and wind speed pairs. We use polynomial chaos (PC), an uncertainty quantification method, to construct a polynomial approximation of the power over the entire stochastic space and to efficiently (using as few simulations as possible) compute the expected power (AEP). We explore both regression and quadrature approaches to compute the PC coefficients. PC based on regression is significantly more efficient than the rectangle rule (the method most commonly used to compute the expected power). With PC based on regression, we have reduced on average by a factor of 5 the number of simulations required to accurately compute the AEP when compared to the rectangle rule for the different wind farm layouts considered. In the wind farm layout optimization problem, each optimization step requires an AEP computation. Thus, the ability to compute the AEP accurately with fewer simulations is beneficial as it reduces the cost to perform an optimization, which enables the use of more computationally expensive higher-fidelity models or the consideration of larger or multiple wind farm optimization problems. We perform a large suite of gradient-based optimizations to compare the optimal layouts obtained when computing the AEP with polynomial chaos based on regression and the rectangle rule. We consider three different starting layouts (Grid, Amalia, Random) and find that the optimization has many local optima and is sensitive to the starting layout of the turbines. We observe that starting from a good layout (Grid, Amalia) will, in general, find better optima than starting from a bad layout (Random) independent of the method used to compute the AEP. For both PC based on regression and the rectangle rule, we consider both a coarse (∼225) and a fine (∼625) number of simulations to compute the AEP. We find that for roughly one-third of the computational cost, the optimizations with the coarse PC based on regression result in optimized layouts that produce comparable AEP to the optimized layouts found with the fine rectangle rule. Furthermore, for the same computational cost, for the different cases considered, polynomial chaos finds optimal layouts with 0.4 % higher AEP on average than those found with the rectangle rule.

This study explores the impact of post-earthquake images inserted in a vigilance task, in terms of performance, self-reports of task-focus, and cerebral activity using functional near-infrared spectroscopy (fNIRS). Vigilance tasks present a sequence of stimuli in which only a few are pre-designated critical or target stimuli requiring an overt response from the participant. Seventy-one residents participated (51 women, 20 men) by taking part in a vigilance task with task-irrelevant images inserted in the sequence. There were three conditions consisting positive (emotive inducing), negative (emotive inducing), and control (devoid of meaning) images embedded in the vigilance task to assess possible impacts on vigilance performance. The images were obtained through crowdsourcing and represented parts of the city 3-4 years post-earthquake. Task performance was assessed with signal detection theory metrics of sensitivity A' and bias β''. This enables the separation of an individual's ability to accurately discriminate critical signals from non-critical stimuli (sensitivity) and shifts in their willingness to respond to any stimuli whether critical or not (bias). Individuals viewing the positive images, relating to progress, rebuild, or aesthetic aspects within the city, had a more conservative response bias (they responded less to both rare critical and distractor stimuli) than those in the other conditions. These individuals also reported lower task-focus, as would be expected. However, contrary to expectations, indicators of cerebral activity (fNIRS) did not differ significantly between the experimental groups. These results, when combined, suggest that mind wandering events may be being generated when exposed to positive post-earthquake images.

All individuals with Down syndrome (DS), which results from trisomy of human chromosome 21 (Ts21), present with skeletal abnormalities typified by craniofacial features, short stature and low bone mineral density (BMD). Differences in skeletal deficits between males and females with DS suggest a sexual dimorphism in how trisomy affects bone. Dp1Tyb mice contain three copies of all of the genes on mouse chromosome 16 that are homologous to human chromosome 21, males and females are fertile, and therefore are an excellent model to test the hypothesis that gene dosage influences the sexual dimorphism of bone abnormalities in DS. Dp1Tyb as compared to control littermate mice at time points associated with bone accrual (6 weeks) and skeletal maturity (16 weeks) showed deficits in BMD and trabecular architecture that occur largely through interactions between sex and genotype and resulted in lower percent bone volume in all female and Dp1Tyb male mice. Cortical bone in Dp1Tyb as compared to control mice exhibited different changes over time influenced by sex × genotype interactions including reduced cortical area in both male and female Dp1Tyb mice. Mechanical testing analyses suggested deficits in whole bone properties such as bone mass and geometry, but improved material properties in female and Dp1Tyb mice. Sexual dimorphisms and the influence of trisomic gene dosage differentially altered cellular properties of male and female Dp1Tyb bone. These data establish sex, gene dosage, skeletal site and age as important factors in skeletal development of DS model mice, paving the way for identification of the causal dosage-sensitive genes. Skeletal differences in developing male and female Dp1Tyb DS model mice replicated differences in less-studied adolescents with DS and established a foundation to understand the etiology of trisomic bone deficits., Highlights • Male and female Down syndrome (DS) mice have distinct differences in skeletal deficits. • Effects of trisomy on bone properties are age and sex dependent. • Different cellular mechanisms may cause bone deficits in male and female DS mice. • Findings of skeletal deficits in DS mice correlate to observations in people with DS.

A new genus and species of fossil caddisfly (Insecta: Trichoptera) from the Lower Eocene (Ypresian) Green River Formation of Colorado is described. Litholimnephilops yinani gen. et sp. nov. is the first adult caddisfly to be described from the Green River Formation, and is characterized by large adult body size, presence of ocelli, dark leg spines, and a lack of terminal crossveins in the anterior anastomosis region of the forewings. Terminal genitalia are not visible in the preserved specimen. Familial placement is uncertain, though similarities with the families Limnephilidae and Phryganeidae are observed.

A new fossil mushroom is described and illustrated from the Lower Cretaceous Crato Formation of northeast Brazil. Gondwanagaricites magnificus gen. et sp. nov. is remarkable for its exceptional preservation as a mineralized replacement in laminated limestone, as all other fossil mushrooms are known from amber inclusions. Gondwanagaricites represents the oldest fossil mushroom to date and the first fossil mushroom from Gondwana.

Norman Ravvin: A goldene medine? A Dialogue in Many Voices on Canadian Jewish Studies and Poland This paper is an account of the conference titled Kanade, di goldene medine? Perspectives on Canadian-Jewish Literature and Culture / Perspectives sur la litterature et la culture juives canadiennes, which took place in Łodź in April, 2014 as a result of collaboration between the University of Łodź and Concordia University (Montreal). As a venue for discussing Canadian Jewish identity and its links with Poland, the conference supported a dialogue between Canadians, Polish Canadianists, and European scholars from further afield. Established and young scholars attended from Germany, the United Kingdom, France, Belgium, the Czech Republic, and Canada, in addition to many Polish participants. The presence of scholars such as Goldie Morgentaler or Sherry Simon as well as curator Barbara Kirshenblatt-Gimblett contributed to an examination of both past and present Canadian and Polish Jewish life and led to an examination of Polish and Canadian literature and history from a highly personal perspective. Conference-goers took advantage of the opportunity to get to know Łodź, via walking tours and a visit to the Łodź Jewish community’s Lauder-funded centre on Narutowicza. The paper aims, as well, to investigate how the history of Jewish Łodź is conveyed in the novels of Joseph Roth and Chava Rosenfarb. The Task of Attention. Sherry Simon (Concordia University) Talks to Krzysztof Majer and Justyna Fruzinska (University of Łodź) American Studies in Poland: A Collective Enterprise. An Interview with Agnieszka Salska by Jadwiga Maszewska and Zbigniew Maszewski (University of Łodź)

The FXLMS algorithm, which is extensively used in active noise control, exhibits frequency dependent convergence behavior. This leads to degraded performance for time-varying and multiple frequency signals. A new algorithm called the eigenvalue equalization filtered-x least mean squares (EE-FXLMS) has been developed to overcome this limitation without increasing the computational burden of the controller. The algorithm is easily implemented for either single or multichannel control. The magnitude coefficients of the secondary path transfer function estimate are altered while preserving the phase. For a reference signal that has the same magnitude at all frequencies, the secondary path estimate is given a flat response over frequency. For a reference signal that contains tonal components of unequal magnitudes, the magnitude coefficients of the secondary path are adjusted to be the inverse magnitude of the reference tones. Both modifications reduce the variation in the eigenvalues of the filtered-x autocorrelation matrix and lead to increased performance. Experimental results show that the EE-FXLMS algorithm provides 3.5-4.4 dB additional attenuation at the error sensor compared to normal FXLMS control. The EE-FXLMS algorithm's convergence rate at individual frequencies is faster and more uniform than the normal FXLMS algorithm with several second improvement being seen in some cases.