Probabilistic assessment of wildfire hazard and municipal watershed exposure

The occurrence of wildfires within municipal watersheds can result in significant impacts to water quality and ultimately human health and safety. In this paper, we illustrate the application of geospatial analysis and burn probability modeling to assess the exposure of municipal watersheds to wildfire. Our assessment of wildfire exposure consists of two primary components: (1) wildfire hazard, which we characterize with burn probability, fireline intensity, and a composite index, and (2) geospatial intersection of watershed polygons with spatially resolved wildfire hazard metrics. This effort enhances investigation into spatial patterns of fire occurrence and behavior and enables quantitative comparisons of exposure across watersheds on the basis of a novel, integrated measure of wildfire hazard. As a case study, we consider the municipal watersheds located on the Beaverhead-Deerlodge National Forest (BDNF) in Montana, United States. We present simulation results to highlight exposure across watersheds and generally demonstrate vast differences in fire likelihood, fire behavior, and expected area burned among the analyzed municipal watersheds. We describe how this information can be incorporated into risk-based strategic fuels management planning and across the broader wildfire management spectrum. To conclude, we discuss strengths and limitations of our approach and offer potential future expansions.Keywords: Hazard analysis, Wildfire, Municipal watersheds, Exposure analysis, Fire modelin

Molecular basis for passive immunotherapy of Alzheimer's disease

Amyloid aggregates of the amyloid-{beta} (A{beta}) peptide are implicated in the pathology of Alzheimer's disease. Anti-A{beta} monoclonal antibodies (mAbs) have been shown to reduce amyloid plaques in vitro and in animal studies. Consequently, passive immunization is being considered for treating Alzheimer's, and anti-A{beta} mAbs are now in phase II trials. We report the isolation of two mAbs (PFA1 and PFA2) that recognize A{beta} monomers, protofibrils, and fibrils and the structures of their antigen binding fragments (Fabs) in complex with the A{beta}(1–8) peptide DAEFRHDS. The immunodominant EFRHD sequence forms salt bridges, hydrogen bonds, and hydrophobic contacts, including interactions with a striking WWDDD motif of the antigen binding fragments. We also show that a similar sequence (AKFRHD) derived from the human protein GRIP1 is able to cross-react with both PFA1 and PFA2 and, when cocrystallized with PFA1, binds in an identical conformation to A{beta}(1–8). Because such cross-reactivity has implications for potential side effects of immunotherapy, our structures provide a template for designing derivative mAbs that target A{beta} with improved specificity and higher affinity

Twitter language use reflects psychological differences between Democrats and Republicans

Previous research has shown that political leanings correlate with various psychological factors. While surveys and experiments provide a rich source of information for political psychology, data from social networks can offer more naturalistic and robust material for analysis. This research investigates psychological differences between individuals of different political orientations on a social networking platform, Twitter. Based on previous findings, we hypothesized that the language used by liberals emphasizes their perception of uniqueness, contains more swear words, more anxiety-related words and more feeling-related words than conservatives' language. Conversely, we predicted that the language of conservatives emphasizes group membership, contains more certainty and more references to achievement and religion than liberals' language. We analysed Twitter timelines of 5,373 followers of three Twitter accounts of the American Democratic and 5,386 followers of three accounts of the Republican parties' Congressional Organizations. The results support most of the predictions and previous findings, confirming that Twitter behaviour offers valid insights to offline behaviour

Synthesis, Spectroscopy and Crystal Structure of a New Copper Complex Built Up by Cationic (Dimethylphosphoryl)methanaminium Ligands

A new transition metal complex of the mono-protonated ligand (dimethylphosphoryl)methanamine (dpmaH+) was obtained by equimolar reaction of copper(II) chloride dihydrate and dpma in concentrated hydrochloric acid. The asymmetric unit of the title structure, [CuCl2(C3H11NOP)4][CuCl4]2, consists of one half of a fourfold charged trans-dichloridotetrakis[(dimethylphosphoryl)methanaminium]copper(II) complex with the copper atom located on an inversion centre and one tetrachloridocuprate(II) dianion found in a general position. The copper centre in the cationic complex shows a tetragonally distorted octahedral environment composed of four oxygen atoms in a square plane and two trans-coordinated chlorido ligands. This 4+2-coordination causes elongated Cu-Cl distances because of the Jahn-Teller effect. The geometry of the tetrachloridocuprate(II) dianion is best described as a seriously distorted tetrahedron. Analysis of the hydrogen bonding scheme by graph-set theory shows three patterns of rings in the title compound. The cationic copper complex reveals intramolecular hydrogen bonds between two aminium groups and the two axial chlorido ligands. Further hydrogen bonding among the cations and anions, more precisely between four aminium groups and the chlorido ligands of four adjacent tetrachloridocuprate(II) anions, lead to a chain-type structure. Comparing the coordination chemistry of the title structure with an analogue cobalt(II) compound only disclose differences in hydrogen bonding pattern resulting in an unusual chain propagation. Besides the crystal structure received spectroscopic data are in accordance with appropriate literature

Neural circuitry for stimulus selection in the zebrafish visual system

When navigating the environment, animals need to prioritize responses to the most relevant stimuli. Although a theoretical framework for selective visual attention exists, its circuit implementation has remained obscure. Here we investigated how larval zebrafish select between simultaneously presented visual stimuli. We found that a mix of winner-take-all (WTA) and averaging strategies best simulates behavioral responses. We identified two circuits whose activity patterns predict the relative saliencies of competing visual objects. Stimuli presented to only one eye are selected by WTA computation in the inner retina. Binocularly presented stimuli, on the other hand, are processed by reciprocal, bilateral connections between the nucleus isthmi (NI) and the tectum. This interhemispheric computation leads to WTA or averaging responses. Optogenetic stimulation and laser ablation of NI neurons disrupt stimulus selection and behavioral action selection. Thus, depending on the relative locations of competing stimuli, a combination of retinotectal and isthmotectal circuits enables selective visual attention

Ethylene Receptor ETHYLENE RECEPTOR1 Domain Requirements for Ethylene Responses in Arabidopsis Seedlings1[W][OA]

Ethylene influences many processes in Arabidopsis (Arabidopsis thaliana) through the action of five receptor isoforms. We used high-resolution, time-lapse imaging of dark-grown Arabidopsis seedlings to better understand the roles of each isoform in the regulation of growth in air, ethylene-stimulated nutations, and growth recovery after ethylene removal. We found that ETHYLENE RECEPTOR1 (ETR1) is both necessary and sufficient for nutations. Transgene constructs in which the ETR1 promoter was used to drive expression of cDNAs for each of the five receptor isoforms were transferred into etr1-6;etr2-3;ein4-4 triple loss-of-function mutants that have constitutive growth inhibition in air, fail to nutate in ethylene, and take longer to recover a normal growth rate when ethylene is removed. The patterns of rescue show that ETR1, ETR2, and ETHYLENE INSENSITIVE4 (EIN4) have the prominent roles in rapid growth recovery after removal of ethylene whereas ETR1 was the sole isoform that rescued nutations. ETR1 histidine kinase activity and phosphotransfer through the receiver domain are not required to rescue nutations. However, REVERSION TO SENSITIVITY1 modulates ethylene-stimulated nutations but does not modulate the rate of growth recovery after ethylene removal. Several chimeric receptor transgene constructs where domains of EIN4 were swapped into ETR1 were also introduced into the triple mutant. The pattern of phenotype rescue by the chimeric receptors used in this study supports a model where a receptor with a receiver domain is required for normal growth recovery and that nutations specifically require the full-length ETR1 receptor

Hepatic phosphorylation status of serine/threonine kinase 1, mammalian target of rapamycin signaling proteins, and growth rate in Holstein heifer calves in response to maternal supply of methionine

The study investigated whether methionine supply during late pregnancy is associated with liver mammalian target of rapamycin (MTOR) pathway phosphorylation, plasma biomarkers, and growth in heifer calves born to cows fed a control diet (CON) or the control diet plus ethylcellulose rumen-protected methionine (MET; 0.09% of dry matter intake) for the last 28 d prepartum. Calves were fed and managed similarly during the first 56 d of age. Plasma was harvested at birth and 2, 7, 21, 42, and 50 d of age and was used for biomarker profiling. Liver biopsies were harvested at 4, 14, 28, and 50 d of age and used for protein expression. Body weight, hip height, hip width, wither height, body length, rectal temperature, fecal score, and respiratory score were measured weekly. Starter intake was measured daily, and average daily gain was calculated during the first 8 wk of age. During the first 7 wk of age, compared with calves in the CON group, calves in the MET group had greater body weight, hip height, wither height, and average daily gain despite similar daily starter intake. Concentration of methionine in plasma was lower at birth but increased markedly at 2 and 7 d of age in MET calves. Plasma insulin, glucose, free fatty acids, and hydroxybutyrate did not differ. A greater ratio of phosphorylated \u3b1-serine/threonine kinase (AKT):total AKT protein expression was detected in MET calves, namely due to differences at 4 d of age. The phosphorylated MTOR:total MTOR ratio also was greater in MET calves due to differences at 28 and 50 d (8 d postweaning). The decrease in phosphorylated MTOR:total MTOR between 14 and 28 d in CON calves agreed with the increase in phosphorylated eukaryotic translation initiation factor 4E binding protein 1 (EIF4EBP1):total EIF4EBP1 ratio during the same time frame. The overall expression of phosphorylated ribosomal protein S6 kinase B1 (RPS6KB1):total RPS6KB1 and phosphorylated eukaryotic translation elongation factor 2 (EEF2):total EEF2 was lower in MET calves. Regardless of methionine supply prepartum, there was an 11-fold temporal decrease from 4 to 50 d in phosphorylated AKT:total AKT. Similarly, regardless of methionine supply, there were overall decreases in phosphorylation ratios of AKT, MTOR, RPS6KB1, and eukaryotic translation initiation factor 2A (EIF2A) over time. Data provide evidence of a positive effect of methionine supply during the last month of pregnancy on rates of growth during the first 7 wk of age. Phosphorylation status of some components of the MTOR pathway in neonatal calf liver also was associated with greater maternal supply of methionine. Thus, the data suggest that molecular mechanisms in the liver might be programmed by supply of methionine during late pregnancy. The exact mechanisms coordinating the observed responses remain to be determined