Damage to tropical forests caused by cyclones is driven by wind speed but mediated by topographical exposure and tree characteristics.

Each year, an average of 45 tropical cyclones affect coastal areas and potentially impact forests. The proportion of the most intense cyclones has increased over the past four decades and is predicted to continue to do so. Yet, it remains uncertain how topographical exposure and tree characteristics can mediate the damage caused by increasing wind speed. Here, we compiled empirical data on the damage caused by 11 cyclones occurring over the past 40 years, from 74 forest plots representing tropical regions worldwide, encompassing field data for 22,176 trees and 815 species. We reconstructed the wind structure of those tropical cyclones to estimate the maximum sustained wind speed (MSW) and wind direction at the studied plots. Then, we used a causal inference framework combined with Bayesian generalised linear mixed models to understand and quantify the causal effects of MSW, topographical exposure to wind (EXP), tree size (DBH) and species wood density (ρ) on the proportion of damaged trees at the community level, and on the probability of snapping or uprooting at the tree level. The probability of snapping or uprooting at the tree level and, hence, the proportion of damaged trees at the community level, increased with increasing MSW, and with increasing EXP accentuating the damaging effects of cyclones, in particular at higher wind speeds. Higher ρ decreased the probability of snapping and to a lesser extent of uprooting. Larger trees tended to have lower probabilities of snapping but increased probabilities of uprooting. Importantly, the effect of ρ decreasing the probabilities of snapping was more marked for smaller than larger trees and was further accentuated at higher MSW. Our work emphasises how local topography, tree size and species wood density together mediate cyclone damage to tropical forests, facilitating better predictions of the impacts of such disturbances in an increasingly windier world.

Make No Apologies: Fear of Negative Evaluation, Depressive Symptoms, and the Mediating Role of Accounting for COVID-Safe Behavior Amongst People at High-Risk for Severe Illness.

With the goal of understanding unique and important threats to the mental health of people who are especially vulnerable to severe illness as a result of COVID-19, this study investigated associations between such individuals' fear of negative evaluation, tendency to "account for" practicing COVID-safe behaviors, and depressive symptoms. Grounded in perspectives on self-presentation, normative influence, and cognitive dissonance, we hypothesized that fear of negative evaluation would relate positively to accounting for COVID-safe behaviors, which, in turn, would associate positively with increased depressive symptoms. The results showed that increased fear of negative evaluation predicted an increased use of apologies and excuses, which in turn were positively related to depressive symptoms. Justifications for COVID-safe behaviors were not significantly associated with either fear of evaluation or depressive symptoms. The practical and theoretical implications are discussed.

Negative Social Exchanges During the Pandemic, Loneliness, and the Mediating Role of Stress and Feeling Misunderstood Among People at High-Risk for COVID-19 Related Complications.

The goal of this study was to investigate the links between social interactions and mental health for people who are high-risk for COVID-19 complications. Specifically, we tested the relationships between negative social exchanges during the pandemic and loneliness through two mediators: stress and feeling misunderstood about one's health status. Data were collected via Amazon's MTurk from participants (N = 271) who self-identified as being high-risk for COVID-19. The results from our model showed both a direct association between negative social interactions and loneliness, and an indirect link between these variables through stress. Overall, these results highlight the importance of understanding social interactions for people who are at high-risk for COVID-19 and their mental well-being. The results and implications are discussed.

Climatic conditions affect shoot flammability by influencing flammability-related functional traits in nonfire-prone habitats.

Plant flammability is an important driver of wildfires, and flammability itself is determined by several plant functional traits. While many plant traits are influenced by climatic conditions, the interaction between climatic conditions and plant flammability has rarely been investigated. Here, we explored the relationships among climatic conditions, shoot-level flammability components, and flammability-related functional traits for 186 plant species from fire-prone and nonfire-prone habitats. For species originating from nonfire-prone habitats, those from warmer areas tended to have lower shoot moisture content and larger leaves, and had higher shoot flammability with higher ignitibility, combustibility, and sustainability. Plants in wetter areas tended to have lower shoot flammability with lower combustibility and sustainability due to higher shoot moisture contents. In fire-prone habitats, shoot flammability was not significantly related to any climatic factor. Our study suggests that for species originating in nonfire-prone habitats, climatic conditions have influenced plant flammability by shifting flammability-related functional traits, including leaf size and shoot moisture content. Climate does not predict shoot flammability in species from fire-prone habitats; here, fire regimes may have an important role in shaping plant flammability. Understanding these nuances in the determinants of plant flammability is important in an increasingly fire-prone world.

Limits to post-fire vegetation recovery under climate change.

Record-breaking fire seasons in many regions across the globe raise important questions about plant community responses to shifting fire regimes (i.e., changing fire frequency, severity and seasonality). Here, we examine the impacts of climate-driven shifts in fire regimes on vegetation communities, and likely responses to fire coinciding with severe drought, heatwaves and/or insect outbreaks. We present scenario-based conceptual models on how overlapping disturbance events and shifting fire regimes interact differently to limit post-fire resprouting and recruitment capacity. We demonstrate that, although many communities will remain resilient to changing fire regimes in the short-term, longer-term changes to vegetation structure, demography and species composition are likely, with a range of subsequent effects on ecosystem function. Resprouting species are likely to be most resilient to changing fire regimes. However, even these species are susceptible if exposed to repeated short-interval fire in combination with other stressors. Post-fire recruitment is highly vulnerable to increased fire frequency, particularly as climatic limitations on propagule availability intensify. Prediction of community responses to fire under climate change will be greatly improved by addressing knowledge gaps on how overlapping disturbances and climate change-induced shifts in fire regime affect post-fire resprouting, recruitment, growth rates, and species-level adaptation capacity.

Making Others Laugh is the Best Medicine: Humor Orientation, Health Outcomes, and the Moderating Role of Cognitive Flexibility.

Humor orientation is related to numerous prosocial outcomes. This study examined the relationships between humor orientation and mental well-being, loneliness, headaches, and sleep disturbances. We also tested cognitive flexibility as a moderator of these associations among (N = 406) young adults. The results showed that humor orientation was associated with increased mental well-being, lower levels of loneliness, and less headaches. The direct effect from humor orientation to sleep disturbances was not significant. The interaction effects between humor orientation and cognitive flexibility on all four health outcome variables were significant. The implications of the results are discussed in detail.

Shoot-level flammability across the Dracophyllum (Ericaceae) phylogeny: evidence for flammability being an emergent property in a land with little fire.

Plant flammability varies across species, but the evolutionary basis for this variation is not well understood. Phylogenetic analysis of interspecific variation in flammability can provide insights into the evolution of plant flammability. We measured four components of flammability (ignitability, sustainability, combustibility and consumability) to assess the shoot-level flammability of 21 species of Dracophyllum (Ericaceae). Using a macroevolutionary approach, we explored phylogenetic patterns of variation in shoot-level flammability. Shoot-level flammability varied widely in Dracophyllum. Species in the subgenus Oreothamnus had higher flammability and smaller leaves than those in the subgenus Dracophyllum. Shoot flammability (ignitability, combustibility and consumability) and leaf length showed phylogenetic conservatism across genus Dracophyllum, but exhibited lability among some closely related species, such as D. menziesii and D. fiordense. Shoot flammability of Dracophyllum species was negatively correlated with leaf length and shoot moisture content, but had no relationship with the geographic distribution of Dracophyllum species. Shoot-level flammability varied widely in the genus Dracophyllum, but showed phylogenetic conservatism. The higher flammability of the subgenus Oreothamnus may be an incidental or emergent property as a result of the evolution of flammability-related traits, such as smaller leaves, which were selected for other functions and incidentally changed flammability.

Src homology 2 domains enhance tyrosine phosphorylation in vivo by protecting binding sites in their target proteins from dephosphorylation.

Phosphotyrosine (pTyr)-dependent signaling is critical for many cellular processes. It is highly dynamic, as signal output depends not only on phosphorylation and dephosphorylation rates but also on the rates of binding and dissociation of effectors containing phosphotyrosine-dependent binding modules such as Src homology 2 (SH2) and phosphotyrosine-binding (PTB) domains. Previous in vitro studies suggested that binding of SH2 and PTB domains can enhance protein phosphorylation by protecting the sites bound by these domains from phosphatase-mediated dephosphorylation. To test whether this occurs in vivo, we used the binding of growth factor receptor bound 2 (GRB2) to phosphorylated epidermal growth factor receptor (EGFR) as a model system. We analyzed the effects of SH2 domain overexpression on protein tyrosine phosphorylation by quantitative Western and far-Western blotting, mass spectrometry, and computational modeling. We found that SH2 overexpression results in a significant, dose-dependent increase in EGFR tyrosine phosphorylation, particularly of sites corresponding to the binding specificity of the overexpressed SH2 domain. Computational models using experimentally determined EGFR phosphorylation and dephosphorylation rates, and pTyr-EGFR and GRB2 concentrations, recapitulated the experimental findings. Surprisingly, both modeling and biochemical analyses suggested that SH2 domain overexpression does not result in a major decrease in the number of unbound phosphorylated SH2 domain-binding sites. Our results suggest that signaling via SH2 domain binding is buffered over a relatively wide range of effector concentrations and that SH2 domain proteins with overlapping binding specificities are unlikely to compete with one another for phosphosites in vivo.

Revealing disease-associated pathways by network integration of untargeted metabolomics.

Uncovering the molecular context of dysregulated metabolites is crucial to understand pathogenic pathways. However, their system-level analysis has been limited owing to challenges in global metabolite identification. Most metabolite features detected by untargeted metabolomics carried out by liquid-chromatography-mass spectrometry cannot be uniquely identified without additional, time-consuming experiments. We report a network-based approach, prize-collecting Steiner forest algorithm for integrative analysis of untargeted metabolomics (PIUMet), that infers molecular pathways and components via integrative analysis of metabolite features, without requiring their identification. We demonstrated PIUMet by analyzing changes in metabolism of sphingolipids, fatty acids and steroids in a Huntington's disease model. Additionally, PIUMet enabled us to elucidate putative identities of altered metabolite features in diseased cells, and infer experimentally undetected, disease-associated metabolites and dysregulated proteins. Finally, we established PIUMet's ability for integrative analysis of untargeted metabolomics data with proteomics data, demonstrating that this approach elicits disease-associated metabolites and proteins that cannot be inferred by individual analysis of these data.

Early signaling dynamics of the epidermal growth factor receptor.

Despite extensive study of the EGF receptor (EGFR) signaling network, the immediate posttranslational changes that occur in response to growth factor stimulation remain poorly characterized; as a result, the biological mechanisms underlying signaling initiation remain obscured. To address this deficiency, we have used a mass spectrometry-based approach to measure system-wide phosphorylation changes throughout the network with 10-s resolution in the 80 s after stimulation in response to a range of eight growth factor concentrations. Significant changes were observed on proteins far downstream in the network as early as 10 s after stimulation, indicating a system capable of transmitting information quickly. Meanwhile, canonical members of the EGFR signaling network fall into clusters with distinct activation patterns. Src homology 2 domain containing transforming protein (Shc) and phosphoinositol 3-kinase (PI3K) phosphorylation levels increase rapidly, but equilibrate within 20 s, whereas proteins such as Grb2-associated binder-1 (Gab1) and SH2-containing tyrosine phosphatase (SHP2) show slower, sustained increases. Proximity ligation assays reveal that Shc and Gab1 phosphorylation patterns are representative of separate timescales for physical association with the receptor. Inhibition of phosphatases with vanadate reveals site-specific regulatory mechanisms and also uncovers primed activating components in the network, including Src family kinases, whose inhibition affects only a subset of proteins within the network. The results presented highlight the complexity of signaling initiation and provide a window into exploring mechanistic hypotheses about receptor tyrosine kinase (RTK) biology.

Intergenerational Transmissions of Mother-Child Loneliness: A Moderated Mediation Model of Familial Social Support and Conflict Avoidance.

Loneliness is a psychological health issue related to deleterious physical health outcomes such as mortality and chronic disease. The aim of this research was to examine intergenerational transmissions of loneliness from mothers to adult child via a moderated mediation model of perceived familial social support and conflict avoidance. Surveys were collected from 146 (N = 292) mother-child dyads on self-reports of loneliness, familial social support, and mother-child conflict avoidance. The results showed that child perceptions of familial social support mediated the relationship between mother-child loneliness. Moreover, child reports of mother-child conflict avoidance moderated the path from familial social support to child loneliness. Specifically, children reported significantly higher levels of loneliness when they perceived low levels of familial social support and high levels of conflict avoidance. These findings expand research on the role of communicative mechanisms in parent-child transmissions of loneliness. The theoretical and practical implications are discussed in detail.

Green firebreaks as a management tool for wildfires: Lessons from China.

Wildfire is a widespread natural hazard that is expected to increase in areal extent, severity and frequency with ongoing changes in climate and land-use. One tool that has been used in an effort to reduce the damage caused by wildfires is green firebreaks: strips of low-flammability vegetation grown at strategic locations in the landscape. Green firebreaks are increasingly being recommended for wildfire management and have been implemented in many countries. The approach is particularly widely used in China, where more than 364,000 km of green firebreaks have been planted and a further 167,000 km are planned for construction before 2025. China is not only a world leader in the implementation of green firebreaks but has also led the way in testing the effectiveness of green firebreaks and in providing guidelines for green firebreak construction. However, most of this research has been reported in the non-English literature, and so is inaccessible to many readers. Here we review the extensive research on the construction and effectiveness of green firebreaks in China and examine how the lessons learned from this research could contribute to the effective implementation of green firebreaks globally. Chinese studies suggest that the ideal species for green firebreaks should meet trait requirements from three perspectives: ecological, silvicultural and economic. Green firebreaks with a multi-layered structure and a closed canopy have the potential to be an effective, long-term, biodiversity-friendly and low-cost tool for fire suppression, although they complement rather than replace other more traditional fire suppression approaches.

Functional and environmental determinants of bark thickness in fire-free temperate rain forest communities.

PREMISE OF THE STUDY: In fire-prone ecosystems, variation in bark thickness among species and communities has been explained by fire frequency; thick bark is necessary to protect cambium from lethal temperatures. Elsewhere this investment is deemed unnecessary, and thin bark is thought to prevail. However, in rain forest ecosystems where fire is rare, bark thickness varies widely among species and communities, and the causes of this variation remain enigmatic. We tested for functional explanations of bark thickness variation in temperate rain forest species and communities. METHODS: We measured bark thickness in 82 tree species throughout New Zealand temperate rain forests that historically have experienced little fire and applied two complementary analyses. First, we examined correlations between bark traits and leaf habit, and leaf and stem traits. Second, we calculated community-weighted mean (CWM) bark thickness for 272 plots distributed throughout New Zealand to identify the environments in which thicker-barked communities occur. KEY RESULTS: Conifers had higher size-independent bark thickness than evergreen angiosperms. Species with thicker bark or higher bark allocation coefficients were not associated with "slow economic" plant traits. Across 272 forest plots, communities with thicker bark occurred on infertile soils, and communities with thicker bark and higher bark allocation coefficients occurred in cooler, drier climates. CONCLUSIONS: In non-fire-prone temperate rain forest ecosystems, investment in bark is driven by soil resources, cool minimum temperatures, and seasonal moisture stress. The role of these factors in fire-prone ecosystems warrants testing.

Taking Blame for Other People's Misconduct.

Taking blame for another person's misconduct may occur at relatively high rates for less serious crimes. The authors examined individual differences and situational factors related to this phenomenon by surveying college students (n = 213) and men enrolled in substance abuse treatment programs (n = 42). Among college students, conscientiousness and delinquency predicted their likelihood of being in a situation in which it was possible to take the blame for another person's misconduct. Situational factors, including the relationship with the perpetrator, the seriousness of the offense, feelings of responsibility for the offense, and differential consequences between the offender and the blame taker, were associated with college students' decisions to take the blame. Among substance abuse treatment participants, individuals who took the blame for another person's misconduct were more extraverted, reported feeling more loyalty toward the true perpetrator, and indicated more incentives to take the blame than individuals who did not take the blame. Links between theories of helping behavior and situational factors that predict blame taking are discussed.

Isoprostane and isofuran lipid mediators accumulate in stored red blood cells and influence platelet function in vitro.

BACKGROUND: Stored red blood cells (RBCs) release hemoglobin (Hb) that leads to oxidative damage, which may contribute to thrombosis in susceptible transfusion recipients. Oxidative stress stimulates the generation of a new class of lipid mediators called F2 -isoprostanes (F2 -IsoPs) and isofurans (IsoFs) that influence cellular behavior. This study investigated RBC-derived F2 -IsoPs and IsoFs during storage and their influence on human platelets (PLTs). STUDY DESIGN AND METHODS: F2 -IsoP and IsoF levels in RBC supernatants were measured by mass spectrometry during storage and after washing. The effects of stored supernatants, cell-free Hb, or a key F2 -IsoP, 8-iso-prostaglandin F2α (PGF2α ), on PLT function were examined in vitro. RESULTS: F2 -IsoPs, IsoFs, and Hb accumulated in stored RBC supernatants. Prestorage leukoreduction reduced supernatant F2 -IsoPs and IsoFs levels, which increased again over storage time. Stored RBC supernatants and 8-iso-PGF2α induced PLT activation marker CD62P (P-selectin) expression and prothrombotic thromboxane A2 release. Cell-free Hb did not alter PLT mediator release, but did inhibit PLT spreading. Poststorage RBC washing reduced F2 -IsoP and IsoF levels up to 24 hours. CONCLUSIONS: F2 -IsoPs and IsoFs are produced by stored RBCs and induce adverse effects on PLT function in vitro, supporting a potential novel role for bioactive lipids in adverse transfusion outcomes. F2 -IsoP and IsoF levels could be useful biomarkers for determining the suitability of blood components for transfusion. A novel finding is that cell-free Hb inhibits PLT spreading and could adversely influence wound healing. Poststorage RBC washing minimizes harmful lipid mediators, and its use could potentially reduce transfusion complications.

Computer aided manual validation of mass spectrometry-based proteomic data.

Advances in mass spectrometry-based proteomic technologies have increased the speed of analysis and the depth provided by a single analysis. Computational tools to evaluate the accuracy of peptide identifications from these high-throughput analyses have not kept pace with technological advances; currently the most common quality evaluation methods are based on statistical analysis of the likelihood of false positive identifications in large-scale data sets. While helpful, these calculations do not consider the accuracy of each identification, thus creating a precarious situation for biologists relying on the data to inform experimental design. Manual validation is the gold standard approach to confirm accuracy of database identifications, but is extremely time-intensive. To palliate the increasing time required to manually validate large proteomic datasets, we provide computer aided manual validation software (CAMV) to expedite the process. Relevant spectra are collected, catalogued, and pre-labeled, allowing users to efficiently judge the quality of each identification and summarize applicable quantitative information. CAMV significantly reduces the burden associated with manual validation and will hopefully encourage broader adoption of manual validation in mass spectrometry-based proteomics.

Blood and urine multi-omics analysis of the impact of e-vaping, smoking, and cessation: from exposome to molecular responses.

Cigarette smoking is a major preventable cause of morbidity and mortality. While quitting smoking is the best option, switching from cigarettes to non-combustible alternatives (NCAs) such as e-vapor products is a viable harm reduction approach for smokers who would otherwise continue to smoke. A key challenge for the clinical assessment of NCAs is that self-reported product use can be unreliable, compromising the proper evaluation of their risk reduction potential. In this cross-sectional study of 205 healthy volunteers, we combined comprehensive exposure characterization with in-depth multi-omics profiling to compare effects across four study groups: cigarette smokers (CS), e-vapor users (EV), former smokers (FS), and never smokers (NS). Multi-omics analyses included metabolomics, transcriptomics, DNA methylomics, proteomics, and lipidomics. Comparison of the molecular effects between CS and NS recapitulated several previous observations, such as increased inflammatory markers in CS. Generally, FS and EV demonstrated intermediate molecular effects between the NS and CS groups. Stratification of the FS and EV by combustion exposure markers suggested that this position on the spectrum between CS and NS was partially driven by non-compliance/dual use. Overall, this study highlights the importance of in-depth exposure characterization before biological effect characterization for any NCA assessment study.

Effective photodynamic therapy against microbial populations in human deep tissue abscess aspirates.

BACKGROUND AND OBJECTIVE: The primary therapy for deep tissue abscesses is drainage accompanied by systemic antimicrobial treatment. However, the long antibiotic course required increases the probability of acquired resistance, and the high incidence of polymicrobial infections in abscesses complicates treatment choices. Photodynamic therapy (PDT) is effective against multiple classes of organisms, including those displaying drug resistance, and may serve as a useful adjunct to the standard of care by reduction of abscess microbial burden following drainage. STUDY DESIGN/MATERIALS AND METHODS: Aspirates were obtained from 32 patients who underwent image-guided percutaneous drainage of the abscess cavity. The majority of the specimens (24/32) were abdominal, with the remainder from liver and lung. Conventional microbiological techniques and nucleotide sequence analysis of rRNA gene fragments were used to characterize microbial populations from abscess aspirates. We evaluated the sensitivity of microorganisms to methylene blue-sensitized PDT in vitro both within the context of an abscess aspirate and as individual isolates. RESULTS: Most isolates were bacterial, with the fungus Candida tropicalis also isolated from two specimens. We examined the sensitivity of these microorganisms to methylene blue-PDT. Complete elimination of culturable microorganisms was achieved in three different aspirates, and significant killing (P < 0.0001) was observed in all individual microbial isolates tested compared to controls. CONCLUSIONS: These results and the technical feasibility of advancing optical fibers through catheters at the time of drainage motivate further work on including PDT as a therapeutic option during abscess treatment.

Stereoselective synthesis of (S)-3-(methylamino)-3-((R)-pyrrolidin-3-yl)propanenitrile.

(S)-3-(methylamino)-3-((R)-pyrrolidin-3-yl)propanenitrile (1) is a key intermediate in the preparation of PF-00951966, (1) a fluoroquinolone antibiotic for use against key pathogens causing community-acquired respiratory tract infections including multidrug resistant (MDR) organisms. The current work describes the development of a highly efficient and stereoselective synthesis of 1 in 10 steps with an overall yield of 24% from readily available benzyloxyacetyl chloride. Two key transformations in the synthetic sequence involve (a) catalytic asymmetric hydrogenation with chiral DM-SEGPHOS-Ru(II) complex to afford ß-hydroxy amide 11b in good yield (73%) and high stereoselectivity (de 98%, ee >99%) after recrystallization and (b) S(N)2 substitution reaction with methylamine to provide diamine 14 with inversion of configuration at the 1'-position in high yield (80%), after efficient purification using a simple acid/base extraction protocol.

Termite sensitivity to temperature affects global wood decay rates.

Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)-even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth's surface.