the interesting scientific paper thread

[DarkStormyKnight]

Hope that this isn't behind a paywall for everyone, but I'm giving a talk on this paper on Monday so figured I'd share here too since I thought it was a fascinating way to analyze ancestry/diversity.

 

Impact of admixture and ancestry on eQTL analysis and GWAS colocalization in GTEx | Genome Biology | Full Text (biomedcentral.com)

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Background

Population structure among study subjects may confound genetic association studies, and lack of proper correction can lead to spurious findings. The Genotype-Tissue Expression (GTEx) project largely contains individuals of European ancestry, but the v8 release also includes up to 15% of individuals of non-European ancestry. Assessing ancestry-based adjustments in GTEx improves portability of this research across populations and further characterizes the impact of population structure on GWAS colocalization.

Results

Here, we identify a subset of 117 individuals in GTEx (v8) with a high degree of population admixture and estimate genome-wide local ancestry. We perform genome-wide cis-eQTL mapping using admixed samples in seven tissues, adjusted by either global or local ancestry. Consistent with previous work, we observe improved power with local ancestry adjustment. At loci where the two adjustments produce different lead variants, we observe 31 loci (0.02%) where a significant colocalization is called only with one eQTL ancestry adjustment method. Notably, both adjustments produce similar numbers of significant colocalizations within each of two different colocalization methods, COLOC and FINEMAP. Finally, we identify a small subset of eQTL-associated variants highly correlated with local ancestry, providing a resource to enhance functional follow-up.

Conclusions

We provide a local ancestry map for admixed individuals in the GTEx v8 release and describe the impact of ancestry and admixture on gene expression, eQTLs, and GWAS colocalization. While the majority of the results are concordant between local and global ancestry-based adjustments, we identify distinct advantages and disadvantages to each approach.

 

[Unleash the Echidnas]

1 hour ago, DarkStormyKnight said:

Hope that this isn't behind a paywall for everyone

Says open access at the top.  I guess one of the underlying things here is genetic diversity is latent if it's not expressed.

 

I'm a bit curious about the choice to define the first five principal components as GlobalAA and use the sixth as LocalAA. Combined with the assumption of a linear model (presumably with Gaussian error), this seems potentially fragile to the robustness of the results. The authors don't mention about testing against that.

[DarkStormyKnight]

21 hours ago, Unleash the Echidnas said:

I'm a bit curious about the choice to define the first five principal components as GlobalAA and use the sixth as LocalAA. Combined with the assumption of a linear model (presumably with Gaussian error), this seems potentially fragile to the robustness of the results. The authors don't mention about testing against that.

I am for sure not an expert on the nitty gritty of the stats in this, but I think that was just for the initial PCA of the genomes, typically LocalAA is performed with a Hidden Markov Model against reference SNP panels of various ancestries. Definitely a good point though!

[Unleash the Echidnas]

They don't mention Markov at all, though. I think it'd take a look in the eQTL citations.

 

It'd probably also help me, at least, to be able to look at the design matrices for the regression. Not my area but the text seems maybe a bit cryptic about the value of m for what appears to be either LocalAA effects or LocalAA covariates.

[Unleash the Echidnas]

Some basic mosquito science, apropos of a recent exchange with @hexingkinase. Like the previous paper from @DarkStormyKnightthis is a gene expression study, in this case identifying and verifying heritability of differences between divergent populations as a way of providing a control to analyses of divergent behavior between other mosquito species. The introduction notes the first ovarian cycle often isn't obligate blood feeding and the discussion notes some of the costs blood meals as a reproductive strategy. I think the most interesting bit is the upregulation of vision in the nonbiting population.

 

Evolutionary transition from blood feeding to obligate nonbiting in a mosquito

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The spread of blood-borne pathogens by mosquitoes relies on their taking a blood meal; if there is no bite, there is no disease transmission. Although many species of mosquitoes never take a blood meal, identifying genes that distinguish blood feeding from obligate nonbiting is hampered by the fact that these different lifestyles occur in separate, genetically incompatible species. There is, however, one unique extant species with populations that share a common genetic background but blood feed in one region and are obligate nonbiters in the rest of their range: Wyeomyia smithii. Contemporary blood-feeding and obligate nonbiting populations represent end points of divergence between fully interfertile southern and northern populations. This divergence has undoubtedly resulted in genetic changes that are unrelated to blood feeding, and the challenge is to winnow out the unrelated genetic factors to identify those related specifically to the evolutionary transition from blood feeding to obligate nonbiting. Herein, we determine differential gene expression resulting from directional selection on blood feeding within a polymorphic population to isolate genetic differences between blood feeding and obligate nonbiting. We show that the evolution of nonbiting has resulted in a greatly reduced metabolic investment compared with biting populations, a greater reliance on opportunistic metabolic pathways, and greater reliance on visual rather than olfactory sensory input. W. smithii provides a unique starting point to determine if there are universal nonbiting genes in mosquitoes that could be manipulated as a means to control vector-borne disease.

[DarkStormyKnight]

OH HELL YEAH

Paper finds that sex differences account for less than 1% of differences in brain structure. 🎉

https://www.sciencedirect.com/science/article/pii/S0149763421000804?fbclid=IwAR3NDGrVeadmOTj6oOgs-_8gafjbRc4n2nuVltGpCoSmgB66teYmVXzIYow

Quote

With the explosion of neuroimaging, differences between male and female brains have been exhaustively analyzed. Here we synthesize three decades of human MRI and postmortem data, emphasizing meta-analyses and other large studies, which collectively reveal few reliable sex/gender differences and a history of unreplicated claims. Males’ brains are larger than females’ from birth, stabilizing around 11% in adults. This size difference accounts for other reproducible findings: higher white/gray matter ratio, intra- versus interhemispheric connectivity, and regional cortical and subcortical volumes in males. But when structural and lateralization differences are present independent of size, sex/gender explains only about 1% of total variance. Connectome differences and multivariate sex/gender prediction are largely based on brain size, and perform poorly across diverse populations. Task-based fMRI has especially failed to find reproducible activation differences between men and women in verbal, spatial or emotion processing due to high rates of false discovery. Overall, male/female brain differences appear trivial and population-specific. The human brain is not “sexually dimorphic.”

 

[Unleash the Echidnas]

A commentary, rather than a full paper, but I think it's reasonably effective as a communication piece connecting the major effects of increasing vapor pressure deficit. It still seems to me much of communication about climate change still favors fairly abstract changes in global average degrees Celsius rather than local effects.

 

Climate change and the aridification of North America

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Discussions of droughts and their impacts often center on the lack of precipitation, just as assessments of hydrologic impacts under a changing climate most often focus on how average precipitation in a given locale is likely to change in the future. Within climate science, however, focus has begun to include the growing role warming temperatures are playing as a potent driver of greater aridity: hotter climate extremes; drier soil conditions; more severe drought; and the impacts of hydrologic stress on rivers, forests, agriculture, and other systems. This shift in the hydrologic paradigm is most clear in the American Southwest, where declining flows in the region’s two most important rivers, the Colorado (Fig. 1) and Rio Grande, have been attributed in part to increasing temperatures caused by human activities, most notably the burning of fossil fuels (1⇓⇓⇓–5). Warmer summers are also likely to reduce flows in the Columbia River, as well as in rivers along the Sierra Nevada in California (6). Now, an important study (7) documents how warming is also causing flow declines in the northern Rocky Mountains and in the largest river basin in the United States, the Missouri. This work further highlights the mechanisms behind the temperature-driven river flow declines and places more focus on how anthropogenic climate warming is progressively increasing the risk of hot drought and more arid conditions across an expanding swath of the United States.

 

[Unleash the Echidnas]

First published answer (preprint was March 3) I'm aware of on the often asked question of what is up with P.1. Central estimate of the reinfection rate is 32% but the trajectory of Figure 4e suggests to me it's plausible that will increase. While it seems likely wealthy countries will have some buffering from vaccination this variant particularly concerns me for the heightened possibility of the combination of vaccination inequity and P.1's mutations producing a distinct set of waves.

 

Genomics and epidemiology of the P.1 SARS-CoV-2 lineage in Manaus, Brazil

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Cases of SARS-CoV-2 infection in Manaus, Brazil, resurged in late 2020, despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1, acquired 17 mutations, including a trio in the spike protein (K417T, E484K and N501Y) associated with increased binding to the human ACE2 receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7–2.4-fold more transmissible, and that previous (non-P.1) infection provides 54–79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.

 

[Unleash the Echidnas]

Basically a roadmap of cultural shifts needed to provide societies with immune system-type defenses against political disinformation. Written by one of the original backfire effect authors with remarks on how backfire has been misrepresented and misinterpreted.

 

Why the backfire effect does not explain the durability of political misperceptions

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Previous research indicated that corrective information can sometimes provoke a so-called “backfire effect” in which respondents more strongly endorsed a misperception about a controversial political or scientific issue when their beliefs or predispositions were challenged. I show how subsequent research and media coverage seized on this finding, distorting its generality and exaggerating its role relative to other factors in explaining the durability of political misperceptions. To the contrary, an emerging research consensus finds that corrective information is typically at least somewhat effective at increasing belief accuracy when received by respondents. However, the research that I review suggests that the accuracy-increasing effects of corrective information like fact checks often do not last or accumulate; instead, they frequently seem to decay or be overwhelmed by cues from elites and the media promoting more congenial but less accurate claims. As a result, misperceptions typically persist in public opinion for years after they have been debunked. Given these realities, the primary challenge for scientific communication is not to prevent backfire effects but instead, to understand how to target corrective information better and to make it more effective. Ultimately, however, the best approach is to disrupt the formation of linkages between group identities and false claims and to reduce the flow of cues reinforcing those claims from elites and the media. Doing so will require a shift from a strategy focused on providing information to the public to one that considers the roles of intermediaries in forming and maintaining belief systems.

 

Tagging @MarRister as some of the sections apply to the Belief Superiority thread.

[Unleash the Echidnas]

If you have a cat, here's a scientific protocol for figuring out your cat's preferences for illusory shapes. I don't have a cat but am tempted to try it with a friend's cats if things ever get normal enough for hanging out indoors while the cats do their things. An artist would just call these negative shapes, though.

 

If I fits I sits: A citizen science investigation into illusory contour susceptibility in domestic cats (Felis silvestris catus)

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A well-known phenomenon to cat owners is the tendency of their cats to sit in enclosed spaces such as boxes, laundry baskets, and even shape outlines taped on the floor. This investigative study asks whether domestic cats (Felis silvestris catus) are also susceptible to sitting in enclosures that are illusory in nature, utilizing cats’ attraction to box-like spaces to assess their perception of the Kanizsa square visual illusion. Carried out during the COVID-19 pandemic, this study randomly assigned citizen science participants Booklets of six randomized, counterbalanced daily stimuli to print out, prepare, and place on the floor in pairs. Owners observed and videorecorded their cats’ behavior with the stimuli and reported findings from home over the course of the six daily trials. This study ultimately reached over 500 pet cats and cat owners, and of those, 30 completed all of the study’s trials. Of these, nine cat subjects selected at least one stimulus by sitting within the contours (illusory or otherwise) with all limbs for at least three seconds. This study revealed that cats selected the Kanizsa illusion just as often as the square and more often than the control, indicating that domestic cats may treat the subjective Kanizsa contours as they do real contours. Given the drawbacks of citizen science projects such as participant attrition, future research would benefit from replicating this study in controlled settings. To the best of our knowledge, this investigation is the first of its kind in three regards: a citizen science study of cat cognition; a formal examination into cats’ attraction to 2D rather than 3D enclosures; and study into cats’ susceptibility to illusory contours in an ecologically relevant paradigm. This study demonstrates the potential of more ecologically valid study of pet cats, and more broadly provides an interesting new perspective into cat visual perception research.

 

[daveb]

Fascinating.

I also like that they used the "If I Fits I Sits" meme in the paper title. 😸

[Unleash the Echidnas]

Kind of disappointed I missed this at the time: Journal retracts bizarre paper about a black hole at the center of Earth

 

In a departure from the thread's usual format for legitimate papers, a bust-down of the pseudoscience publishing ring's misconduct by Dr. Elies Bik is here with a bit more from Vice here.

 

Also, there's a long write up of Johnathan Pruitt's data falsification out this week.

[Unleash the Echidnas]

All about how the pandemic works at the molecular level and how this affects neutralization and vaccine efficacy.

 

SARS-CoV-2 variants, spike mutations and immune escape

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Although most mutations in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome are expected to be either deleterious and swiftly purged or relatively neutral, a small proportion will affect functional properties and may alter infectivity, disease severity or interactions with host immunity. The emergence of SARS-CoV-2 in late 2019 was followed by a period of relative evolutionary stasis lasting about 11 months. Since late 2020, however, SARS-CoV-2 evolution has been characterized by the emergence of sets of mutations, in the context of ‘variants of concern’, that impact virus characteristics, including transmissibility and antigenicity, probably in response to the changing immune profile of the human population. There is emerging evidence of reduced neutralization of some SARS-CoV-2 variants by postvaccination serum; however, a greater understanding of correlates of protection is required to evaluate how this may impact vaccine effectiveness. Nonetheless, manufacturers are preparing platforms for a possible update of vaccine sequences, and it is crucial that surveillance of genetic and antigenic changes in the global virus population is done alongside experiments to elucidate the phenotypic impacts of mutations. In this Review, we summarize the literature on mutations of the SARS-CoV-2 spike protein, the primary antigen, focusing on their impacts on antigenicity and contextualizing them in the protein structure, and discuss them in the context of observed mutation frequencies in global sequence datasets.

 

[Unleash the Echidnas]

Social distancing by ants. Maybe I'm just pessimistic but it seems like it'd be interesting to have deeper access into the ant movement database. Because I'd be interested in testing two hypothesis. One, after normalizing for their situations, that the ants most successful in distancing achieve transmission reductions comparable to humans who are most successful in distancing. Two, the least successful ants are more successful than the least successful humans.

 

Social network plasticity decreases disease transmission in a eusocial insect

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Animal social networks are shaped by multiple selection pressures, including the need to ensure efficient communication and functioning while simultaneously limiting disease transmission. Social animals could potentially further reduce epidemic risk by altering their social networks in the presence of pathogens, yet there is currently no evidence for such pathogen-triggered responses. We tested this hypothesis experimentally in the ant Lasius niger using a combination of automated tracking, controlled pathogen exposure, transmission quantification, and temporally explicit simulations. Pathogen exposure induced behavioral changes in both exposed ants and their nestmates, which helped contain the disease by reinforcing key transmission-inhibitory properties of the colony’s contact network. This suggests that social network plasticity in response to pathogens is an effective strategy for mitigating the effects of disease in social groups.

 

[daveb]

Interesting (at least the parts I could understand).  

 

I wonder about this part, and if humans could do better if we could directly and "rapidly detect the presence of a pathogen" in our own selves. Of course there would also need to be societal support for people to take time off from work and do whatever other measures would be needed to isolate, especially when people aren't manifesting serious symptoms. We are often under various pressures to "soldier on" with things like minor colds, and even flu and other illnesses, much less asymptomatic cases that might still spread symptomatic cases to others.

Quote

this study shows that both pathogen-exposed and untreated workers are able to rapidly detect the presence of a pathogen and immediately adjust their behavior to reinforce the disease-inhibitory effects of the colony’s social network, thus reducing individual contamination risk.

 

[Unleash the Echidnas]

Model output, so not really a lore drop, but probably the closest thing to it that's available. Figure 2 is good for showing how the shift in global land initiated by European colonial resource extraction and extended by the industrial revolution leads population expansion. All of the figures use the same varying x axis scale since changes since 1700 CE are so dramatic compared to the preceding 11.7 ka. I also found it interesting to compare the relative land use shifts from the Black Death in Europe to the population crash in Latin America in the 1500s CE.

 

Given AVEN's Eurocentricism as a result of being mainly English speaking I suspect most readers here have some awareness of the Black Death (Yersinia pestis) and its maybe 35% mortality rate. See Acuna-Soto et al. 2002 for a short introduction the 90% mortality just in Mexico caused by European diseases, cocoliztli, and probably drought interactions. Subsequent genomic analysis indicates for cocolitztli as Salmonella enterica ssp enterica (Vågene et al. 2018, Unpaywall).

 

People have shaped most of terrestrial nature for at least 12,000 years

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Archaeological and paleoecological evidence shows that by 10,000 BCE, all human societies employed varying degrees of ecologically transformative land use practices, including burning, hunting, species propagation, domestication, cultivation, and others that have left long-term legacies across the terrestrial biosphere. Yet, a lingering paradigm among natural scientists, conservationists, and policymakers is that human transformation of terrestrial nature is mostly recent and inherently destructive. Here, we use the most up-to-date, spatially explicit global reconstruction of historical human populations and land use to show that this paradigm is likely wrong. Even 12,000 y ago, nearly three quarters of Earth’s land was inhabited and therefore shaped by human societies, including more than 95% of temperate and 90% of tropical woodlands. Lands now characterized as “natural,” “intact,” and “wild” generally exhibit long histories of use, as do protected areas and Indigenous lands, and current global patterns of vertebrate species richness and key biodiversity areas are more strongly associated with past patterns of land use than with present ones in regional landscapes now characterized as natural. The current biodiversity crisis can seldom be explained by the loss of uninhabited wildlands, resulting instead from the appropriation, colonization, and intensifying use of the biodiverse cultural landscapes long shaped and sustained by prior societies. Recognizing this deep cultural connection with biodiversity will therefore be essential to resolve the crisis.

(replies on other things later)

[Unleash the Echidnas]

Somewhat apropos of the western megadrought thread. these are global statistics showing increases in water coming off the land exceed increases in precipitation. Streamflow and stored water therefore decline. Water budgets are hard to close so it's cool to see all the models and data products converging fairly well.

 

While I could quibble over the perceptual uniformity of the colormaps chosen, I think alpha blended, shading based approaches are the most effective way of showing probability distributions that's readily available (e.g. ggplot() + geom_rect(aes(alpha = ...))). I also think showing distributions is particularly important for variable and hard to measure time series like the ones here. Methodologically, regressing on predictors and then looking for insignificant trend in the residuals is a bit uncommon but it strikes me as kind of elegant given the residual SLR (simple linear regression) used.

 

A 10 per cent increase in global land evapotranspiration from 2003 to 2019

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Accurate quantification of global land evapotranspiration is necessary for understanding variability in the global water cycle, which is expected to intensify under climate change. Current global evapotranspiration products are derived from a variety of sources, including models, remote sensing, and in situ observations. However, existing approaches contain extensive uncertainties; for example, relating to model structure or the upscaling of observations to a global level. As a result, variability and trends in global evapotranspiration remain unclear12. Here we show that global land evapotranspiration increased by 10 ± 2 per cent between 2003 and 2019, and that land precipitation is increasingly partitioned into evapotranspiration rather than runoff. Our results are based on an independent water-balance ensemble time series of global land evapotranspiration and the corresponding uncertainty distribution, using data from the Gravity Recovery and Climate Experiment (GRACE) and GRACE-Follow On (GRACE-FO) satellites13. Variability in global land evapotranspiration is positively correlated with El Niño–Southern Oscillation. The main driver of the trend, however, is increasing land temperature. Our findings provide an observational constraint on global land evapotranspiration, and are consistent with the hypothesis that global evapotranspiration should increase in a warming climate.

 

 

[Unleash the Echidnas]

Yay, reasonably robust numbers, maps, and monthly bars, though publication lag means the analysis period is the last 8.5 months of 2020 and therefore any shift from α can't be detected. The aggregate 20% guessestimate that's been used for the past year and some is pretty close, though. I'm a bit disappointed a fitted model wasn't used to predict outside of the United States but at least the discussion is decent about citing similar work in other countries. So there is some ability for readers to extrapolate to their locations.

 

Role of meteorological factors in the transmission of SARS-CoV-2 in the United States

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Improved understanding of the effects of meteorological conditions on the transmission of SARS-CoV-2, the causative agent for COVID-19 disease, is needed. Here, we estimate the relationship between air temperature, specific humidity, and ultraviolet radiation and SARS-CoV-2 transmission in 2669 U.S. counties with abundant reported cases from March 15 to December 31, 2020. Specifically, we quantify the associations of daily mean temperature, specific humidity, and ultraviolet radiation with daily estimates of the SARS-CoV-2 reproduction number (Rt) and calculate the fraction of Rt attributable to these meteorological conditions. Lower air temperature (within the 20–40 °C range), lower specific humidity, and lower ultraviolet radiation were significantly associated with increased Rt. The fraction of Rt attributable to temperature, specific humidity, and ultraviolet radiation were 3.73% (95% empirical confidence interval [eCI]: 3.66–3.76%), 9.35% (95% eCI: 9.27–9.39%), and 4.44% (95% eCI: 4.38–4.47%), respectively. In total, 17.5% of Rt was attributable to meteorological factors. The fractions attributable to meteorological factors generally were higher in northern counties than in southern counties. Our findings indicate that cold and dry weather and low levels of ultraviolet radiation are moderately associated with increased SARS-CoV-2 transmissibility, with humidity playing the largest role.

 

[Unleash the Echidnas]

Clever paper. Basically, take the sarbecovirus interactome and look back in human DNA to see when it evolved. Considering the uncertainty in molecular clocks, there's a regional match between the human side and the virus side. The authors are careful to point out this correlation doesn't indicate causation but it is consistent with the idea there's a 24 ka history of zoonotic coronaviruses.

 

An ancient viral epidemic involving host coronavirus interacting genes more than 20,000 years ago in East Asia

Quote

The current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has emphasized the vulnerability of human populations to novel viral pressures, despite the vast array of epidemiological and biomedical tools now available. Notably, modern human genomes contain evolutionary information tracing back tens of thousands of years, which may help identify the viruses that have impacted our ancestors—pointing to which viruses have future pandemic potential. Here, we apply evolutionary analyses to human genomic datasets to recover selection events involving tens of human genes that interact with coronaviruses, including SARS-CoV-2, that likely started more than 20,000 years ago. These adaptive events were limited to the population ancestral to East Asian populations. Multiple lines of functional evidence support an ancient viral selective pressure, and East Asia is the geographical origin of several modern coronavirus epidemics. An arms race with an ancient coronavirus, or with a different virus that happened to use similar interactions as coronaviruses with human hosts, may thus have taken place in ancestral East Asian populations. By learning more about our ancient viral foes, our study highlights the promise of evolutionary information to better predict the pandemics of the future. Importantly, adaptation to ancient viral epidemics in specific human populations does not necessarily imply any difference in genetic susceptibility between different human populations, and the current evidence points toward an overwhelming impact of socioeconomic factors in the case of coronavirus disease 2019 (COVID-19).

 

[crazy ace]

@Unleash the Echidnas

A bit off topic, but how do you find all of these papers? They're all very interesting (granted, I suppose) and informative!

[Unleash the Echidnas]

A bit about heterogeneity within and between fires. I'm used to this spatial and temporal diversity since I've been around wildfires for years but refugia aren't often mentioned about outside of fire science.

 

Where and why do conifer forests persist in refugia through multiple fire events?

Quote

Changing wildfire regimes are causing rapid shifts in forests worldwide. In particular, forested landscapes that burn repeatedly in relatively quick succession may be at risk of conversion when pre-fire vegetation cannot recover between fires. Fire refugia (areas that burn less frequently or severely than the surrounding landscape) support post-fire ecosystem recovery and the persistence of vulnerable species in fire-prone landscapes. Observed and projected fire-induced forest losses highlight the need to understand where and why forests persist in refugia through multiple fires. This research need is particularly acute in the Klamath-Siskiyou ecoregion of southwest Oregon and northwest California, USA, where expected increases in fire activity and climate warming may result in the loss of up to one-third of the region's conifer forests, which are the most diverse in western North America. Here, we leverage recent advances in fire progression mapping and weather interpolation, in conjunction with a novel application of satellite smoke imagery, to model the key controls on fire refugia occurrence and persistence through one, two, and three fire events over a 32-year period. Hotter-than-average fire weather was associated with lower refugia probability and higher fire severity. Refugia that persisted through three fire events appeared to be partially entrained by landscape features that offered protection from fire, suggesting that topographic variability may be an important stabilizing factor as forests pass through successive fire filters. In addition, smoke density strongly influenced fire effects, with fire refugia more likely to occur when smoke was moderate or dense in the morning, a relationship attributable to reduced incoming solar radiation resulting from smoke shading. Results from this study could inform management strategies designed to protect fire-resistant portions of biologically and topographically diverse landscapes.

 

On 6/26/2021 at 3:04 PM, crazy ace said:

A bit off topic, but how do you find all of these papers? They're all very interesting (granted, I suppose) and informative!

Mostly people I follow, skipping from news headlines to the actual work, citations within things I'm reading, citations of things I'm reading, and looks at authors' works published.

[daveb]

On the subject of forest fires I was just reading about "zombie fires". These are fires that basically go underground (literally and/or figuratively) during the winter and then make a resurgence when the weather warms up again up in places like northern Canada, Alaska, and Siberia. And they are apparently becoming worse with climate change, in that there are more of them and some of them burn more acreage.  

 

Reference: https://www.nature.com/articles/s41586-021-03437-y

[crazy ace]

I just remembered this paper I read a while back:

Superconductivity in rare earth cuprate perovskites

After reading it, I was obsessed with the matter for weeks.

However, it looks inaccessible without institutional access. Best I can supply is the abstract :(.

Quote

Superconducting cuprate perovskites isostructural with Ba₂YCu₃O₇ incorporating a variety of rare earth ions are reported. Resistivity and magnetic susceptibility measurements show transition temperatures in excess of 90K for several materials, including Nd, Sm, Gd, Dy, Ho, Er and Lu-containing phases. Interestingly, Ce and Tb, with a readily accessible 4+ state, form phases other than the defect perovskite which are not superconductors. However, Pr, which also has an accessible 4+ state, does give a nonsuperconducting defect perovskite isostructural with Ba₂YCu₃O₇. The observation of high temperature superconductivity in phases containing ions carrying magnetic moments is significant because it suggests that the magnetic moment on the rare earth ion interacts only weakly with the electrons making up the band crucial to superconductivity in these materials.

The paper's relatively old, from 1987.

There may or may not be a pirated version somewhere online.

[Unleash the Echidnas]

7 minutes ago, crazy ace said:

After reading it, I was obsessed with the matter for weeks. However, it looks inaccessible without institutional access.

Maybe try Hancock et al. 2015 or related citations? (All I did was skim a topic search for a recent open review.)

[crazy ace]

Evolving Successful Stack Overflow Attacks for Vulnerability Testing

Evolutionary programming and hacking.

Pretty interesting stuff.

Quote

The work presented in this paper is intended to test crucial system services against stack overflow vulnerabilities. The focus of the test is the user-accessible variables, that is to say, the inputs from the user as specified at the command line or in a configuration file. The tester is defined as a process for automatically generating a wide variety of user-accessible variables that result in malicious buffers (an exploit). In this work, the search for successful exploits is formulated as an optimization problem and solved using evolutionary computation. Moreover the resulting attacks are passed through the Snort misuse detection system to observe the detection (or not) of each exploit.

 

[crazy ace]

27 minutes ago, crazy ace said:

Evolving Successful Stack Overflow Attacks for Vulnerability Testing

Evolutionary programming and hacking.

Pretty interesting stuff.

 

On that note, if you look at the directory that this is stored under, belonging to one Dr. Zincir, you'll find a lot of similar articles, detailing exploits and EP, although there's also some supercomputer shit involved as well