Miracle-dz/UniFAR-FTUs huggingface dataset:
Eigenvalue Estimates for the Weighted Laplacian on Metric Trees

The Laplacian on a metric tree is Δ u = u″ on its edges, with the appropriate compatibility conditions at the vertices. We study the eigenvalue problem on a rooted tree Γ: −λΔu=Vuon Γ,u(o)=0. Here V ⩾ 0 is a given ‘weight function’ on Γ, and o is the root of Γ. The eigenvalues for such a problem decay no faster than λn = O(n−2), this last case being typical for one‐dimensional problems. We obtain estimates for the eigenvalues in the classes lp, with p > ½, and their weak analogues lp, ∞ with p ⩾ ½. The results for p<1 and p>1 are of different character. The case p<1 is studied in more detail. To analyse this case, we use two methods; in both of them the problem is reduced to a family of one‐dimensional problems. One of the methods is based upon a useful orthogonal decomposition of the Dirichlet space on Γ. For a particular class of trees and weights, this method leads to the complete spectral analysis of the problem. We illustrate this in several examples, where we were able to obtain the asymptotics of the eigenvalues. 1991 Mathematics Subject Classification: primary 47E05, 05C05; secondary 34L15, 34L20.
Representation and Aggression in Digital Racial Conflict: Analyzing Public Comments during Live-Streamed News of Racial Justice Protests

How do local citizens publicly converse online about the protests that follow when police kill Black residents? And do participants reflect local publics? Here we examine racial justice protests in Baton Rouge after police killed Alton Sterling in 2016. Local news streamed the protests on Facebook Live. In comments appearing below the video, locals supported and attacked each other in real-time while watching protests unfold. We assess a representative sample of these comments. First, we find surprising demographic and political representativeness in comments compared to census data and a local survey. We also document extensive hostile rhetoric corresponding with commenter traits and expressed views. Finally, we find more “likes” for comments by women, college-educated people, and locals. Violent and racially derogatory comments by Blacks received fewer likes, but similar comments by whites went unpenalized. The results illuminate social media functions in local politics, racial disparities in contentious digital dialogues, and political communication’s dual roles in strengthening and undermining multiracial democracy.
Mining tourism in abandoned and existing mines in the Swedish Far North

Abstract The Swedish North is sometimes described as a resource periphery, while others choose to label it a pleasure periphery. Regardless of the terms used, the region is characterised by problems such as out-migration and demographic issues. This study investigates why there are such different perceptions of the same area, and whether there is any contradiction between extractive resource industries and the tourism industry. This is done by collecting visitor data from mining companies and conducting interviews with a variety of respondents in three mining communities in northern Sweden. Mining tourism is a phenomenon occurring in this region and can be regarded as a context in which the two main narratives meet while being a rather overlooked form of tourism. This is partly due to the low level of knowledge regarding its impacts, but also to a somewhat established idea of mining tourism as a “bad” form of tourism. Individuals’ perceptions of mining tourism as a phenomenon seem to be highly value-related and influenced by both location and occupation. As such, various opinions can be explained by social exchange theory, which proposes that attitudes will be influenced by individuals’ evaluation of outcomes for themselves and their community. In this paper, the emergence of mining tourism is understood as knowledge creation rooted in a regional path dependency on mining and tourism. Hence, mining tourism becomes a new regional tourism product that contributes to tourism, at least in terms of standard technical visits and, at best, a well-developed tourist attraction that appeals to visitors in quantities similar to iconic regional attractions such as the Icehotel. Then again, a tourism industry selling dreams of “untouched nature” argues that this tourism product produces “bad imaging”.
An Investigation of a Three-Dimensional Asymmetric Vortex

Abstract A three-dimensional numerical simulation is presented for the asymmetric vortex motion which occurs in a Ward-type vortex chamber. The initial state is taken to be one of axisymmetric irrotational flow where the flow enters through the sides at the bottom and exits through the top of the chamber. As tangential velocity is added to the inflowing fluid, the structure of the flow in the meridional plane is modified from a ‘one-celled’ flow(updraft everywhere) to a ‘two-celled’ flow (updraft surrounding a central downdraft). Asymmetric vortices develop in the location of maximum vorticity of the ‘two-celled’ vortex which, it is shown, must be in the gradient between the updraft and the downdraft (but in updraft). Structural features of these asymmetric vortices, such as the tilt with height and propagation rate, are examined. Although the laboratory model upon which the present numerical calculations are based lacks the ability to simulate some important aspects of atmospheric flow, several significa.
Source–sink flow inside a rotating cylindrical cavity

The axisymmetric flow inside a rotating cavity with radial outflow or inflow of fluid is discussed. The basic theoretical model of Hide (1968) is extended, using the integralmomentum techniques of von Kármán (1921), to include laminar and turbulent flows; both linear and nonlinear equations are considered. The size of the source region is estimated using a ‘free disk’ model for the outflow case and a free vortex for the inflow case. In both cases, the estimates are in good agreement with available experimental data. Theoretical values of the tangential component of the velocity outside the Ekman layers on the disks, obtained from solutions of the laminar and turbulent integral equations, are compared with experimental values. The experiments were conducted in a number of rotating-cavity rigs, with a radial outflow or inflow of air, and laser-Doppler anemometry was used to measure the velocity in the ‘interior core’ between the Ekman layers. The measurements provide good support for the theoretical models over a wide range of flow rates, rotational speeds and radial locations. Although only isothermal flow is considered in this paper, the methods can be readily extended to non-isothermal flow and heat transfer.
Effects of Terrain Height and Blocking Initialization on Numerical Simulation of Alpine Lee Cyclogenesis

Abstract A series of numerical experiments were performed to test the evolution of lee cyclones with various terrain representations, and also to test forecast sensitivity to initial wind fields. Using the data set collected during the operational phase of the ALPEX field experiment, a mesoscale model was initialized with data from two markedly different cases, 12 hours prior to formation of a cyclone in the Mediterranean. The terrain used ranged from flat, sea level terrain, to orography that conserved the maximum barrier height of the Alps (similar to “envelope” terrain currently in use at the European Centre for Medium Range Weather Forecasting). Results showed that even in the 12-hour period preceding cyclogenesis the mountain plays a crucial role in the evolution of the cyclone. Sharp variation in position and strength was evident depending on the terrain employed. Comparison of terrain versus no-terrain cases showed perturbations that compare well with those proposed in a recently published theory.
Long-term variations of solar activity affect the earth's climatic conditions modulating the characteristics of the middle atmosphere

Abstract The balance of rates of solar energy input and output determines the thermal status of the surface atmosphere. The solar activity increase leads to a decrease of the lower atmosphere energy sink and consequently to warming. Also, a solar activity decrease signifies cooling. It is shown that the long-term decrease of the solar activity (like during the Maunder Minimum) can provoke an atmospheric temperature lowering of about 1K over 100 years.
Measuring Heterogeneous Preferences for Adaptation Strategies in Response to Sea Level Rise: Evidence from Miami-Dade County

Despite mounting threats from rising sea levels, adaptation to sea level rise (SLR) is often challenged by limited funding and understanding of residents’ preferences. Using an online choice experiment, we investigate residents’ preference for three SLR adaptation strategies: building seawalls, replenishing the beach, and installing stormwater pumps in Miami-Dade County. We control the preference, scale, and alternative heterogeneity using generalized multinomial logit models with error components. Results show that residents prefer additional adaptation strategies to the status quo, and valuations of adaptation attributes are correlated with residents’ sociodemographics. Accounting for alternative heterogeneity also significantly improves model performance.
On the Diffuse Non-thermal Emission from Galaxy Clusters

We use the results from a constrained, cosmological MHD simulation of the Local Universe to predict the radio halo and the γ-ray flux from the Coma cluster and compare it to current observations. The simulated magnetic field within the Coma cluster is the result of turbulent amplification of the magnetic field during build-up of the cluster. The magnetic seed field originates from star-burst driven, galactic outflows. The synchrotron emission is calculated assuming a hadronic model. We follow four approaches with different distributions for the cosmic-ray proton (CRp) population within galaxy clusters. The radial profile of the radio halo can only be reproduced with a radially increasing energy fraction within the cosmic-ray proton population, reaching >100% of the thermal energy content at ≈ 1Mpc, e.g. the edge of the radio emitting region. Additionally the spectral steepening of the observed radio halo in Coma cannot be reproduced, even when accounting for the negative flux from the thermal SZ effect at high frequencies. Therefore the hadronic models are disfavoured from present analysis. The emission of γ-rays expected from our simulated Coma is still below the current observational limits (by a factor of ∼6) but would be detectable by FERMI observations in the near future. Accepted to MNRAS 3 Sep 2009; Published in volume 401, Jan 2010 80 5. Radio Halos From Hadronic Models I: The Coma cluster 0.01 0.10 r/rvir 10 10 10 10
Antimicrobial susceptibility testing for diverse Malassezia species

The genus Malassezia is an opportunistic lipid-dependent yeast that is associated with common skin diseases and has recently been associated with Crohn’s disease and certain cancers. Understanding the susceptibility of Malassezia to diverse antimicrobial agents is crucial for identifying effective antifungal therapies. Here, we tested the efficacy of isavuconazole, itraconazole, terbinafine and artemisinin against three Malassezia species: M. restricta, M. slooffiae, and M. sympodialis, using microbroth dilution techniques. We found antifungal properties for the two previously-unstudied antimicrobials: isavuconazole and artemisinin. Overall all Malassezia species were particularly susceptible to itraconazole, with a MIC range from 0.0015 to 0.1562 μM. Importance The Malassezia genus is known to be a cause of skin conditions and has recently been associated with diseases such as Crohn’s disease, pancreatic ductal carcinoma and breast cancer. This work was completed to assess the susceptibility to a variety of antimicrobial drugs on diverse Malassezia species, in particular Malassezia restricta.
TMPRSS2 Is Essential for SARS-CoV-2 Beta and Omicron Infection

The COVID-19 pandemic remains a global health threat and novel antiviral strategies are urgently needed. SARS-CoV-2 employs the cellular serine protease TMPRSS2 for entry into lung cells and TMPRSS2 inhibitors are being developed for COVID-19 therapy. However, the SARS-CoV-2 Omicron variant, which currently dominates the pandemic, prefers the endo/lysosomal cysteine protease cathepsin L over TMPRSS2 for cell entry, raising doubts whether TMPRSS2 inhibitors would be suitable for treatment of patients infected with the Omicron variant. Nevertheless, the contribution of TMPRSS2 to spread of SARS-CoV-2 in the infected host is largely unclear. Here, we show that loss of TMPRSS2 strongly reduced the replication of the Beta variant in nose, trachea and lung of C57BL mice and protected the animals from weight loss and disease. Infection of mice with the Omicron variant did not cause disease, as expected, but again TMPRSS2 was essential for efficient viral spread in the upper and lower respiratory tract. These results identify a key role of TMPRSS2 in SARS-CoV-2 Beta and Omicron infection and highlight TMPRSS2 as an attractive target for antiviral intervention.
Color and gloss constancy under diverse lighting environments

When we look at an object, we simultaneously see how glossy or matte it is, how light or dark, and what color. Yet, at each point on the object’s surface, both diffuse and specular reflections are mixed in different proportions, resulting in substantial spatial chromatic and luminance variations. To further complicate matters, this pattern changes radically when the object is viewed under different lighting conditions. The purpose of this study was to simultaneously measure our ability to judge color and gloss using an image set capturing diverse object and illuminant properties. Participants adjusted the hue, lightness, chroma, and specular reflectance of a reference object so that it appeared to be made of the same material as a test object. Critically, the two objects were presented under different lighting environments. We found that hue matches were highly accurate, except for under a chromatically atypical illuminant. Chroma and lightness constancy were generally poor, but these failures correlated well with simple image statistics. Gloss constancy was particularly poor, and these failures were only partially explained by reflection contrast. Importantly, across all measures, participants were highly consistent with one another in their deviations from constancy. Although color and gloss constancy hold well in simple conditions, the variety of lighting and shape in the real world presents significant challenges to our visual system’s ability to judge intrinsic material properties.
The effects of pks+ Escherichia coli and bile acid in colorectal tumorigenesis among people with cholelithiasis or cholecystectomy

Patients with cholelithiasis (CL) or cholecystectomy (CE) would have more chances to get colorectal adenoma (CRA) or cancer (CRC). To figure out the effect of gut microbiota and bile acid on colorectal neoplasm in CL and CE patients, we executed a retrospective observational study recruited 463 volunteers, including 182 people with normal gallbladder (Normal), 135 CL and 146 CE patients. The discovery cohort was established to explore the difference of gut microbiota through 16S rRNA sequencing. The validation cohort aimed to verify the results of sequencing through qPCR. Through this research, significant enrichment of Escherichia coli was found in patients with cholelithiasis or cholecystectomy both in discovery cohort (PNormal-CL=0.013; PNormal-CE=0.042) and in validation cohort (PNormal-CL<0.0001; PNormal-CE<0.0001). The relative abundance of Escherichia coli was also increased in CRA and CRC patients (in discovery cohort, PHC-CRA=0.045, PHC-CRC=0.0016; in validation cohort, PHC-CRA=0.0063, PHC-CRC=0.0007). Pks+Escherichia coli was found enriched in CL and CE patients in validation cohort (PNormal-CL<0.0001; PNormal-CE<0.0001). Through KEGG analysis in discovery cohort, the differences of bile acid metabolism were revealed (Ko00120 primary bile acid biosynthesis P=0.014; Ko00121 secondary bile acid biosynthesis P=0.010). In validation cohort, we also found the elevation of serum total bile acid of CE patients (P<0.0001). And the level of serum total bile acid was found associated with the relative abundance of pks+ Escherichia coli (r=0.1895, P=0.0012). In one word, our research found that Escherichia coli, especially pks+ species, was enriched in CL and CE patients. Pks+ Escherichia coli and bile acid metabolism were associated with CRA and CRC in people after cholecystectomy.
Biochemistry-informed design selects potent siRNAs against SARS-CoV-2

RNA interference (RNAi) offers an efficient way to repress genes of interest, and it is widely used in research settings. Clinical applications emerged more recently, with 5 approved siRNAs (the RNA guides of the RNAi effector complex) against human diseases. The development of siRNAs against the SARS-CoV-2 virus could therefore provide the basis of novel COVID-19 treatments, while being easily adaptable to future variants or to other, unrelated viruses. Because the biochemistry of RNAi is very precisely described, it is now possible to design siRNAs with high predicted activity and specificity using only computational tools. While previous siRNA design algorithms tended to rely on simplistic strategies (raising fully complementary siRNAs against targets of interest), our approach uses the most up-to-date mechanistic description of RNAi to allow mismatches at tolerable positions and to force them at beneficial positions, while optimizing siRNA duplex asymmetry. Our pipeline proposes 8 siRNAs against SARS-CoV-2, and ex vivo assessment confirms the high antiviral activity of 6 out of 8 siRNAs, also achieving excellent variant coverage (with several 3-siRNA combinations recognizing each correctly-sequenced variant as of September 2022). Our approach is easily generalizable to other viruses as long as a variant genome database is available. With siRNA delivery procedures being currently improved, RNAi could therefore become an efficient and versatile antiviral therapeutic strategy.
Coupled carbon and nitrogen cycling regulates the cnidarian–algal symbiosis

Efficient nutrient recycling underpins the ecological success of the cnidarian-algal symbiosis in oligotrophic waters. In a stable symbiosis, nitrogen limitation restricts the growth of algal endosymbionts and stimulates their release of photosynthates to the cnidarian animal host. However, the detailed mechanisms controlling nitrogen availability in hospite and their role in symbiosis regulation remain poorly understood. Here, we studied the metabolic regulation of symbiotic nitrogen cycling in the sea anemone Aiptasia by experimentally altering labile carbon availability in a series of experiments. Combining 13C and 15N stable isotope labeling experiments with physiological analyses and NanoSIMS imaging, we show that the competition for environmental ammonium between the host and its algal symbionts is regulated by labile carbon availability. Light regimes optimal for algal photosynthesis increased carbon availability in the holobiont and stimulated nitrogen assimilation in the host metabolism. Consequently, algal symbiont densities were lowest under optimal environmental conditions and increased toward the symbiosis’s lower and upper light tolerance limits. This metabolic regulation promotes efficient carbon recycling in a stable symbiosis across a wide range of environmental conditions. At the same time, the dependence on resource competition may favor parasitic interactions explaining the instability of the symbiosis as the environmental conditions in the Anthropocene shift towards its tolerance limits.
Spatial and Spectral Components of the BOLD Global Signal in Rat Resting-State Functional MRI

In resting-state fMRI (rs-fMRI), the global signal average captures widespread fluctuations related to unwanted sources of variance such as motion and respiration, and has long been used as a regressor to reduce noise during data preprocessing. However, coherent neural activity in spatially-extended functional networks can also contribute to the global signal. The relative contributions of neural and non-neural sources to the global signal remain poorly understood. This study sought to tackle this problem through the comparison of the blood oxygenation level dependent (BOLD) global signal to an adjacent non-brain tissue signal from the same scan in rs-fMRI obtained from anesthetized rats. In this dataset motion was minimal and ventilation was phase-locked to image acquisition to minimize respiratory fluctuations. In addition to contrasting the spatial and spectral components of these two signals, we also observed these differences across the use of three different anesthetics: isoflurane, dexmedetomidine, and a combination of dexmedetomidine and light isoflurane. Here, we report differences in the spectral composition of the two signals as evaluated by a power spectral density (PSD) estimate and a fractional amplitude of low-frequency fluctuations (fALFF) calculation. Additionally, we show spatial selectivity for specific brain structures that show an increased correlation to the global signal both statically and dynamically, through Pearson’s correlation and co-activation pattern analysis, respectively. All of the observed differences between the BOLD global signal and the adjacent non-brain tissue signal were maintained across all three anesthetic conditions, showing that the global signal is distinct from the noise contained in the tissue signal. This study provides a unique perspective to the contents of the global signal and their origins.
Transposable elements contribute to the establishment of the glycine shuttle in Brassicaceae species

C3-C4 intermediate photosynthesis has evolved at least five times convergently in the Brassicaceae, despite this family lacking bona fide C4 species. The establishment of this carbon concentrating mechanism is known to require a complex suite of ultrastructural modifications as well as changes in spatial expression patterns, which are both thought to be underpinned by a reconfiguration of existing gene-regulatory networks. However, to date, the mechanisms which underpin the reconfiguration of these gene networks are largely unknown. In this study, we used a pan-genomic association approach to identify genomic features that could confer differential gene expression toward the C3-C4 intermediate state by analysing eight C3 species and seven C3-C4 species from five independent origins in the Brassicaceae. We found a strong correlation between transposable element (TE) insertions in cis-regulatory regions and the C3-C4 intermediacy. Specifically, our study revealed 113 gene models in which presence of a TE within a gene correlates with C3-C4 intermediate photosynthesis. In this set, genes involved in the photorespiratory glycine shuttle are enriched, including the glycine decarboxylase P-protein whose expression domain undergoes a spatial shift during the transition to C3-C4 photosynthesis. When further interrogating this gene, we discovered independent TE insertions in its upstream region which we conclude to be responsible for causing the spatial shift in GLDP1 gene expression. Our findings hint at a pivotal role of TEs in the evolution of C3-C4 intermediacy, especially in mediating differential spatial gene expression.