Abstract
Although research has identified many suicide risk factors, the relationship between financial strain and suicide has received less attention. Using data representative of the US adult ...population (n = 34,653) from wave 1 (2001–2002) and wave 2 (2004–2005) of the National Epidemiologic Survey on Alcohol and Related Conditions, we investigated the association between financial strain—financial debt/crisis, unemployment, past homelessness, and lower income—and subsequent suicide attempts and suicidal ideation. Multivariable logistic regression controlling for demographic and clinical covariates showed that cumulative financial strain was predictive of suicide attempts between waves 1 and 2 (odds ratio (OR) = 1.53, 95% confidence interval (CI): 1.32, 1.77). Wave 1 financial debt/crisis (OR = 1.58, 95% CI: 1.06, 2.34), unemployment (OR = 1.52, 95% CI: 1.10, 2.10), past homelessness (OR = 1.50, 95% CI: 1.03, 2.17), and lower income (OR = 1.51, 95% CI: 1.01, 2.25) were each associated with subsequent suicide attempts. Respondents endorsing these 4 financial-strain variables had 20 times higher predicted probability of attempting suicide compared with respondents endorsing none of these variables. Analyses yielded similar results examining suicidal ideation. Financial strain accumulated from multiple sources (debt, housing instability, unemployment, and low income) should be considered for optimal assessment, management, and prevention of suicide.
Background
There are significant concerns about mental health problems occurring due to the coronavirus disease 2019 (COVID‐19) pandemic. To date, there has been limited empirical investigation about ...thoughts of suicide and self‐harm during the COVID‐19 pandemic.
Methods
A national survey was conducted May 2020 to investigate the association between mental health symptoms, social isolation, and financial stressors during the COVID‐19 pandemic and thoughts of suicide and self‐harm. A total of 6607 US adults completed an online survey; survey criteria included an age minimum of 22 years old and reported annual gross income of $75,000 or below. Statistical raking procedures were conducted to more precisely weight the sample using US Census data on age, geographic region, sex, race, and ethnicity.
Results
COVID‐19‐related stress symptoms, loneliness, and financial strain were associated with thoughts of suicide/self‐harm in multivariable logistic regression analyses, as were younger age, being a military veteran, past homelessness, lifetime severe mental illness, current depressive symptoms, alcohol misuse, and having tested positive for COVID‐19. Greater social support was inversely related to thoughts of suicide/self‐harm whereas running out of money for basic needs (e.g., food), housing instability (e.g., delaying rent), and filing for unemployment or disability were positively related.
Conclusions
Public health interventions to decrease risk of suicide and self‐harm in the wake of the COVID‐19 pandemic should address pandemic‐related stress, social isolation, and financial strain experienced including food insecurity, job loss, and risk of eviction/homelessness.
The longstanding, successful use of herbal drug combinations in traditional medicine makes it necessary to find a rationale for the pharmacological and therapeutic superiority of many of them in ...comparison to isolated single constituents. This review describes many examples of how modern molecular–biological methods (including new genomic technologies) can enable us to understand the various synergistic mechanisms underlying these effects. Synergistic effects can be produced if the constituents of an extract affect different targets or interact with one another in order to improve the solubility and thereby enhance the bioavailability of one or several substances of an extract. A special synergy effect can occur when antibiotics are combined with an agent that antagonizes bacterial resistance mechanisms. The verification of real synergy effects can be achieved through detailed pharmacological investigations and by means of controlled clinical studies performed in comparison with synthetic reference drugs. All the new ongoing projects aim at the development of a new generation of phytopharmaceuticals which can be used alone or in combination with synthetic drugs or antibiotics. This new generation of phytopharmaceuticals could lend phytotherapy a new legitimacy and enable their use to treat diseases which have hitherto been treated using synthetic drugs alone.
In this article, the authors present their point of view on whether an analogy can be drawn between nano and classical microcomposites. Their opinion corresponds with a 25-year-old opinion article by ...Calvert and is based on their own extensive studies and a large body of studies in the scientific literature. They propose that polymer nanocomposites are in fact quasi-homogeneous molecular blends, which ought to be regarded as molecular composites or self-reinforced polymers. Hence, the micromechanical models of classical composites may not generally apply to nanocomposites, where—instead—the interactions on a molecular scale between the nanoparticles and the polymer matrix control the properties. A few examples, including of nucleation and confinement by nanoparticles, are discussed.
We previously reported on an SOS-induced toxin, TisB, in Escherichia coli and its regulation by the RNA antitoxin IstR-1. Here, we addressed the mode of action of TisB. By placing the tisB reading ...frame downstream of a controllable promoter on a plasmid, toxicity could be analysed in the absence of the global SOS response. Upon induction of TisB, cell growth was inhibited and plating efficiency decreased rapidly. The onset of toxicity correlated with a drastic decrease in transcription, translation and replication rates. Cellular RNA was degraded, but in vitro experiments showed that TisB did not affect translation or transcription directly. Thus, these effects are downstream consequences of membrane damage: TisB is predicted to be hydrophobic and membrane spanning, and Western analyses demonstrated that this peptide was strictly localized to the cytoplasmic membrane fraction. Membrane damage and cell killing under tisB multicopy expression are also seen by live/death staining and the formation of ghost cells. This is reminiscent of another toxin, Hok of plasmid R1, which also targets the membrane. The biological significance of the istR/tisB locus is still elusive; deletion of the entire locus gave no fitness phenotype in competition experiments.
Helicoidal formations often appear in natural microstructures such as bones and arthropods exoskeletons. Named Bouligands after their discoverer, these structures are angle-ply laminates that ...assemble from laminae of chitin or collagen fibers embedded in a proteinaceous matrix. High resolution electron microscope images of cross-sections through scorpion claws are presented here, uncovering structural features that are different than so-far assumed. These include in-plane twisting of laminae around their corners rather than through their centers, and a second orthogonal rotation angle which gradually tilts the laminae out-of-plane. The resulting Bouligand laminate unit (BLU) is highly warped, such that neighboring BLUs are intricately intertwined, tightly nested and mechanically interlocked. Using classical laminate analysis extended to laminae tilting, it is shown that tilting significantly enhances the laminate flexural stiffness and strength, and may improve toughness by diverting crack propagation. These observations may be extended to diverse biological species and potentially applied to synthetic structures.
Paenibacillus polymyxa is a plant growth-promoting rhizobacterium with a broad host range, but so far the use of this organism as a biocontrol agent has not been very efficient. In previous work we ...showed that this bacterium protects Arabidopsis thaliana against pathogens and abiotic stress (S. Timmusk and E. G. H. Wagner, Mol. Plant-Microbe Interact. 12:951-959, 1999; S. Timmusk, P. van West, N. A. R. Gow, and E. G. H. Wagner, p. 1-28, in Mechanism of action of the plant growth promoting bacterium Paenibacillus polymyxa, 2003). Here, we studied colonization of plant roots by a natural isolate of P. polymyxa which had been tagged with a plasmid-borne gfp gene. Fluorescence microscopy and electron scanning microscopy indicated that the bacteria colonized predominantly the root tip, where they formed biofilms. Accumulation of bacteria was observed in the intercellular spaces outside the vascular cylinder. Systemic spreading did not occur, as indicated by the absence of bacteria in aerial tissues. Studies were performed in both a gnotobiotic system and a soil system. The fact that similar observations were made in both systems suggests that colonization by this bacterium can be studied in a more defined system. Problems associated with green fluorescent protein tagging of natural isolates and deleterious effects of the plant growth-promoting bacteria are discussed.
Mapping the spatial distribution of a plant is a current challenge in ecology. Here, a convolutional neural network (CNN) and 33,798 Sentinel-2 satellite images were used to detect and map forest ...stands dominated by trees of the genus Pleroma by their magenta-to-deep-purple blossoms in the entire Brazilian Atlantic Forest domain, from June 2016 to July 2020. The Pleroma genus, known for its pioneer behaviour, was detected in an area representing 10.8% of the Atlantic Forest, associated negatively with temperature and positively with elevation, slope, tree cover and precipitation. The detection of another genus by the model, 18% of all the detections contained only pink blooming Handroanthus trees, highlighted that botanical identification from space must be taken with caution, particularly outside the known distribution range of the species. The Pleroma blossom seasonality occurred over a period of ~5-6 months centered on the March equinox and populations with distinct blossom timings were found. Our results indicate that in the Atlantic Forest, the remaining natural forest is less diverse than expected but is at least recovering from degradation. Our study suggests a method to produce ecological-domain scale maps of tree genera and species based on their blossoms that could be used for tree studies and biodiversity assessments.
Species spatial distributions are the result of population demography, behavioral traits, and species interactions in spatially heterogeneous environmental conditions. Hence the composition of ...species assemblages is an integrative response variable, and its variability can be explained by the complex interplay among several structuring factors. The thorough analysis of spatial variation in species assemblages may help infer processes shaping ecological communities. We suggest that ecological studies would benefit from the combined use of the classical statistical models of community composition data, such as constrained or unconstrained multivariate analyses of site-by-species abundance tables, with rapidly emerging and diversifying methods of spatial pattern analysis. Doing so allows one to deal with spatially explicit ecological models of beta diversity in a biogeographic context through the multiscale analysis of spatial patterns in original species data tables, including spatial characterization of fitted or residual variation from environmental models. We summarize here the recent progress for specifying spatial features through spatial weighting matrices and spatial eigenfunctions in order to define spatially constrained or scale-explicit multivariate analyses. Through a worked example on tropical tree communities, we also show the potential of the overall approach to identify significant residual spatial patterns that could arise from the omission of important unmeasured explanatory variables or processes.
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