Miracle-dz/UniFAR-FTUs huggingface dataset:
Community Structure, Species Variation, and Potential Functions of Rhizosphere-Associated Bacteria of Different Winter Wheat (Triticum aestivum) Cultivars

Minimal tillage management of extensive crops like wheat can provide significant environmental services but can also lead to adverse interactions between soil borne microbes and the host. Little is known about the ability of the wheat cultivar to alter the microbial community from a long-term recruitment standpoint, and whether this recruitment is consistent across field sites. To address this, nine winter wheat cultivars were grown for two consecutive seasons on the same plots on two different farm sites and assessed for their ability to alter the rhizosphere bacterial communities in a minimal tillage system. Using deep amplicon sequencing of the V1–V3 region of the 16S rDNA, a total of 26,604 operational taxonomic units (OTUs) were found across these two sites. A core bacteriome consisting of 962 OTUs were found to exist in 95% of the wheat rhizosphere samples. Differences in the relative abundances for these wheat cultivars were observed. Of these differences, 24 of the OTUs were found to be significantly different by wheat cultivar and these differences occurred at both locations. Several of the cultivar-associated OTUs were found to correspond with strains that may provide beneficial services to the host plant. Network correlations demonstrated significant co-occurrences for different taxa and their respective OTUs, and in some cases, these interactions were determined by the wheat cultivar. Microbial abundances did not play a role in the number of correlations, and the majority of the co-occurrences were shown to be positively associated. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States was used to determine potential functions associated with OTUs by association with rhizosphere members which have sequenced metagenomics data. Potentially beneficial pathways for nitrogen, sulfur, phosphorus, and malate metabolism, as well as antimicrobial compounds, were inferred from this analysis. Differences in these pathways and their associated functions were found to differ by wheat cultivar. In conclusion, our study suggests wheat cultivars are involved in shaping the rhizosphere by differentially altering the bacterial OTUs consistently across different sites, and these altered bacterial communities may provide beneficial services to the host.
Stereo vision-based obstacle avoidance for micro air vehicles using disparity space

We address obstacle avoidance for outdoor flight of micro air vehicles. The highly textured nature of outdoor scenes enables camera-based perception, which will scale to very small size, weight, and power with very wide, two-axis field of regard. In this paper, we use forward-looking stereo cameras for obstacle detection and a downward-looking camera as an input to state estimation. For obstacle representation, we use image space with the stereo disparity map itself. We show that a C-space-like obstacle expansion can be done with this representation and that collision checking can be done by projecting candidate 3-D trajectories into image space and performing a z-buffer-like operation with the disparity map. This approach is very efficient in memory and computing time. We do motion planning and trajectory generation with an adaptation of a closed-loop RRT planner to quadrotor dynamics and full 3D search. We validate the performance of the system with Monte Carlo simulations in virtual worlds and flight tests of a real quadrotor through a grove of trees. The approach is designed to support scalability to high speed flight and has numerous possible generalizations to use other polar or hybrid polar/Cartesian representations and to fuse data from additional sensors, such as peripheral optical flow or radar.
Network Analysis with the Enron Email Corpus

We use the Enron email corpus to study relationships in a network by applying six different measures of centrality. Our results came out of an in-semester undergraduate research seminar. The Enron corpus is well suited to statistical analyses at all levels of undergraduate education. Through this article's focus on centrality, students can explore the dependence of statistical models on initial assumptions and the interplay between centrality measures and hierarchical ranking, and they can use completed studies as springboards for future research. The Enron corpus also presents opportunities for research into many other areas of analysis, including social networks, clustering, and natural language processing.
Hyperpolarization-activated “pacemaker current” — A funny current in models of SA nodal pacemaker cells

A typical feature of sinoatrial (SA) nodal pacemaker cells is the presence of an ionic current that activates upon hyperpolarization. The contribution of this hyper-polarization-activated current, If, which is also known as the “funny current” or “pacemaker current”, to the spontaneous pacemaker activity of SA nodal cells remains a matter of intense debate. We used experimentally recorded action potentials of a single isolated rabbit SA nodal pacemaker cell to reconstruct the time course of If according to the mathematical models of Maltsev and Lakatta (2009) and Severi et al. (2012). The thus reconstructed If was compared to that obtained with a simple and straightforward first-order Hodgkin and Huxley-type model of If based on experimental data acquired in our laboratory. In terms of steady-state activation and fully-activated current amplitude, the model of Maltsev and Lakatta (2009) better fits our experimental data than that of Severi et al. (2012). However, with both models, the reconstructed time course of If shows several discrepancies with the time course based on our experimental data, which is largely due to the almost instantaneous deactivation of If at depolarized potentials in either model.
Study of the centralization level of optical network-supported Cloud RAN

Radio Access Network (RAN) costs savings are expected in future Cloud RAN (C-RAN). Differently from traditional distributed RAN architecture, in C-RAN Remote Radio Heads (RRH) from different sites can share baseband processing resources from virtualized Base Band Unit (BBU) pools placed in few central locations (CO). Due to the stringent requirements of the several interfaces needed in C-RAN, optical networks have been proposed to support it. In this paper, we present the C-RAN Capital Expenditures (CAPEX) minimization problem to decide which COs should be equipped and the equipment to be installed. Several problem instances considering different Long Term Evolution-Advanced (LTE-A) configurations are solved to study the impact of the centralization level C-RAN in terms of both, CAPEX and Operational Expenditures (OPEX). Compared to the maximum centralization level, results showed remarkable costs savings when a lower level of centralization is considered.
Numerical Simulation of Magnetohydrodynamic Forced Convective Boundary Layer Flow past a Stretching/Shrinking Sheet Prescribed with Variable Heat Flux in the Presence of Heat Source and Constant Suction

A study has been carried out on MHD boundary layer forced convection flow along a shrinking surface with variable heat flux in the presence of heat source. The flow is generated due to linear shrinking of the sheet and is influenced by uniform transverse magnetic field. The basic boundary layer momentum and heat transfer equations, which are nonlinear partial differential equations, are converted into nonlinear ordinary differential equations by means of similarity transformation. Numerical solution of the resulting boundary value problem is obtained using Nachtsheim Swigert shooting iteration scheme for the satisfaction of asymptotic boundary conditions along with the Fourth Order Runge Kutta method. The effects of suction parameter, magnetic parameter, Prandtl number, heat source parameter, stretching/shrinking parameter and heat flux parameter on velocity and temperature are shown in several plots. The results are in good agreement with the earlier published works under some limiting cases. Skin friction coefficient and wall temperature are also explored for typical values of the parameter involved in the study.
Spatial memory and hippocampal volume in humans with unilateral vestibular deafferentation

Patients with acquired chronic bilateral vestibular loss were recently found to have a significant impairment in spatial memory and navigation when tested with a virtual Morris water task. These deficits were associated with selective and bilateral atrophy of the hippocampus, which suggests that spatial memory and navigation also rely on vestibular input. In the present study 16 patients with unilateral vestibular deafferentation due to acoustic neurinoma were examined 5‐ to 13‐yrs post‐surgery. Volumetry of the hippocampus was performed in patients and age‐ and sex‐matched healthy controls by manually tracing the structure and by an evaluator‐independent voxel‐based morphometry. Spatial memory and navigation were assessed with a virtual Morris water task. No significant deficits in spatial memory and navigation could be demonstrated in the patients with left vestibular failure, whereas patients with right vestibular loss showed a tendency to perform worse on the respective tests. Impairment was significant only for one computed measure (heading error). The subtle deficiencies with right vestibular loss are compatible with the recently described dominance of the right labyrinth and the vestibular cortex in the right hemisphere. Volumetry did not reveal any atrophy of the hippocampus in either patient group. © 2007 Wiley‐Liss, Inc.
Conditional random fields for activity recognition in smart environments

One of the most common functions of smart environments is to monitor and assist older adults with their activities of daily living. Activity recognition is a key component in this application. It is essentially a temporal classification problem which has been modeled in the past by naïve Bayes classifiers and hidden Markov models (HMMs). In this paper, we describe the use of another probabilistic model: Conditional Random Fields (CRFs), which is currently gaining popularity for its remarkable performance for activity recognition. Our focus is on using CRFs to recognize activities performed by an inhabitant in a smart home environment and our goal is to validate the claim of its higher or similar performance by comparing CRFs with HMMs using data collected in a real smart home.
DANCING WITH NEIGHBOURS: CO-MOVEMENT BETWEEN SOUTH AFRICA AND SADC

This paper uses a novel dynamic factor model a la Forni et al. (2001) to investigate the impact of increasing trade on the co-movement of the business cycle between South Africa and the Southern African Development Community (SADC) countries. The results show a moderate but increasing synchronization between South Africa and SADC countries, in contrast with the already existing high correlation between the South African business cycle with the G-7 countries and most emerging market countries. This is evidence of the increasing importance and spread of the forces of globalization , reflected in the increasing integration of goods and services through international trade. The striking result is that South Africa, justified by its geographical location and increased trade integration in the SADC, cannot isolate itself from its SADC neighbours, and that regional policy coordination is of the utmost importance.
The Dynamics of Tail-like Current Sheets under the Innuence of Small-scale Plasma Turbulence

A 2D-magnetohydrodynamic model of current-sheet dynamics caused by anomalous electrical resistivity as result of small-scale plasma turbulence is proposed. The anomalous resistivity is assumed to be proportional to the square of the gradient of the magnetic pressure as may be valid for instance in the case of lower-hybrid-drift turbulence. The initial resistivity pulse is given. Then the temporal and spatial evolution of the magnetic and electric elds, plasma density, pressure, convection and resistivity are considered. The motion of the induced electric eld is discussed as indicator of the plasma disturbances. The obtained results found using much improved numerical methods show a magnetic eld evolution with x-line formation and plasma acceleration. Besides, in the current sheet, three types of magnetohydrodynamic waves occur, fast magnetoacoustic waves of compression and rarefaction as well as slow magnetoacoustic waves.
FLOW BEHIND BLUFF BODIES IN SIDE-BY-SIDE ARRANGEMENT

The present investigation deals with the shedding of vortices and flow interference between two circular cylinders in a side-by-side arrangement. Simulations are carried out using commercial Computational Fluid Dynamics (CFD) code FLUENT-6.2. The flow field around the cylinders is modeled in two-dimensions with the axis of the cylinder perpendicular to the direction of flow. The cylinder is modeled as a circle and a square flow domain is created around the cylinder. The calculations are carried out on a quadrilateral mesh. The simulations are performed for a Reynolds number of 200. The mesh is finer close to the cylinder wall in order to have a better description of the boundary layer. Contours of vorticity, variation of lift and drag coefficients, force time histories are presented. A mean repulsive lift force exists between the cylinders and the lift force steadily decreases with increasing length to diameter ratio. For length to diameter ratio ≤ 2.0, flopping phenomenon is observed whereas for length to diameter ratio > 2.0, the lift fluctuation is synchronized and is in antiphase. The results of the present work show that the drag coefficient is slightly higher for length to diameter ratio of 2.0. Beyond this ratio, the drag coefficient on either cylinder falls. For length to diameter ratio of 3.0 and 4.0, the power spectrum estimation of the lift coefficient shows a very distinctive peak at Strouhal number of 0.21.
Atmospheric Chemistry and Physics Aerosol Optical Properties Relevant to Regional Remote Sensing of Ccn Activity and Links to Their Organic Mass Fraction: Airborne Observations over Central Mexico and the Us West Coast during Milagro/intex-b

Remote sensing of cloud condensation nuclei (CCN) would help evaluate the indirect effects of tropo-spheric aerosols on clouds and climate. To assess its feasibility , we examined relationships of submicron aerosol composition to CCN activity and optical properties observed during the MILAGRO/INTEX-B aircraft campaigns. An indicator of CCN activity, κ, was calculated from hygroscopicity measured under saturation. κ for dry 100 nm particles decreased with increasing organic fraction of non-refractory mass of submicron particles (OMF) as 0.34–0.20×OMF over Central Mexico and 0.47–0.43×OMF over the US West Coast. These fits represent the critical dry diameter, centered near 100 nm for 0.2% supersaturation but varied as κ (−1/3) , within measurement uncertainty (∼20%). The decreasing trends of CCN activity with the organic content, evident also in our direct CCN counts, were consistent with previous ground and laboratory observations of highly organic particles. The wider range of OMF, 0–0.8, for our research areas means that aerosol composition will be more critical for estimation of CCN concentration than at the fixed sites previously studied. Furthermore, the wavelength dependence of extinction was anti-correlated with OMF as −0.70×OMF+2.0 for Central Mexico's urban and industrial pollution air masses, for unclear reasons. The Angstrom exponent of absorption increased with OMF, more rapidly under higher single scattering albedo, as expected for the interplay between soot and colored weak absorbers (some organic species and dust). Because remote sensing products currently use the wavelength dependence of extinction albeit in the column integral form and may potentially include that of absorption, these regional spectral dependencies are expected to facilitate retrievals of aerosol bulk chemical composition and CCN activity over Central Mexico.
THE FIRST HUNDRED BROWN DWARFS DISCOVERED BY THE WIDE-FIELD INFRARED SURVEY EXPLORER (WISE)

We present ground-based spectroscopic verification of 6 Y dwarfs (see also Cushing et al.), 89 T dwarfs, 8 L dwarfs, and 1 M dwarf identified by the Wide-field Infrared Survey Explorer (WISE). Eighty of these are cold brown dwarfs with spectral types ⩾T6, six of which have been announced earlier by Mainzer et al. and Burgasser et al. We present color–color and color–type diagrams showing the locus of M, L, T, and Y dwarfs in WISE color space. Near-infrared and, in a few cases, optical spectra are presented for these discoveries. Near-infrared classifications as late as early Y are presented and objects with peculiar spectra are discussed. Using these new discoveries, we are also able to extend the optical T dwarf classification scheme from T8 to T9. After deriving an absolute WISE 4.6 μm (W2) magnitude versus spectral type relation, we estimate spectrophotometric distances to our discoveries. We also use available astrometric measurements to provide preliminary trigonometric parallaxes to four of our discoveries, which have types of L9 pec (red), T8, T9, and Y0; all of these lie within 10 pc of the Sun. The Y0 dwarf, WISE 1541−2250, is the closest at 2.8+1.3−0.6 pc; if this 2.8 pc value persists after continued monitoring, WISE 1541−2250 will become the seventh closest stellar system to the Sun. Another 10 objects, with types between T6 and >Y0, have spectrophotometric distance estimates also placing them within 10 pc. The closest of these, the T6 dwarf WISE 1506+7027, is believed to fall at a distance of ∼4.9 pc. WISE multi-epoch positions supplemented with positional info primarily from the Spitzer/Infrared Array Camera allow us to calculate proper motions and tangential velocities for roughly one-half of the new discoveries. This work represents the first step by WISE to complete a full-sky, volume-limited census of late-T and Y dwarfs. Using early results from this census, we present preliminary, lower limits to the space density of these objects and discuss constraints on both the functional form of the mass function and the low-mass limit of star formation.
Nuclear star formation in NGC 6240

We have made use of archival HST BVIJH photometry to constrain the nature of the three discrete sources, A1, A2 and B1, identified in the double nucleus of NGC 6240. STARBURST99 models have been fitted to the observed colours, under the assumption, first, that these sources can be treated as star clusters (i.e. single, instantaneous episodes of star formation), and subsequently as star-forming regions (i.e. characterised by continuous star formation). For both scenarios, we estimate ages as young as 4 million years, integrated masses ranging between $7\, \times\, 10^6~M_{\odot}$ (B1) and 10$^9~M_{\odot}$ (A1) and a rate of 1 supernova per year, which, together with the stellar winds, sustains a galactic wind of 44 $M_{\odot}$ yr -1 . In the case of continuous star formation, a star-formation rate has been derived for A1 as high as 270 $M_{\odot}$ yr -1 , similar to what is observed for warm Ultraluminous Infrared Galaxies (ULIRGs) with a double nucleus. The A1 source is characterised by a mass density of about 1200 $M_{\odot}$ pc -3 which resembles the CO molecular mass density measured in cold ULIRGs and the stellar density determined in “elliptical core” galaxies. This, together with the recent discovery of a supermassive binary black hole in the double nucleus of NGC 6240, might indicate that the ongoing merger could shape the galaxy into a core elliptical.
Photometric variability in the open cluster M 67 - I. Cluster members detected in X-rays

We study photometric variability among the optical counterparts of X-ray sources in the old open cluster M 67. The two puzzling binaries below the giant branch are both variables: for S 1113 the photometric period is compatible with the orbital period, S 1063 either varies on a period longer than the orbital period, or does not vary periodically. For the spectroscopic binaries S 999, S 1070 and S 1077 the photometric and orbital periods are similar. Another new periodic variable is the main-sequence star S 1112, not known to be a binary. An increase of the photometric period in the W UMa system S 1282 (AH Cnc) is in agreement with a previously reported trend. Six of the eight variables we detected are binaries with orbital periods of 10 days or less and equal photometric and orbital periods. This confirms the interpretation that their X-ray emission arises in the coronae of tidally locked magnetically active stars. No variability was found for the binaries with orbital periods longer than 40 days; their X-ray emission remains to be explained.
Contagion in an interacting economy

We investigate the credit risk model defined in Hatchett and Kühn (2006 J. Phys. A: Math. Gen. 39 2231) under more general assumptions, in particular using a general degree distribution for sparse graphs. Expanding upon earlier results, we show that the model is exactly solvable in the N → ∞ limit and demonstrate that the exact solution is described by the message-passing approach outlined in Karrer and Newman (2010 Phys. Rev. E 82 016101), generalized to include heterogeneous agents and couplings. We provide comparisons with simulations of graph ensembles with power-law degree distributions.
Dynamic Evolution of Telomeric Sequences in the Green Algal Order Chlamydomonadales

Telomeres, which form the protective ends of eukaryotic chromosomes, are a ubiquitous and conserved structure of eukaryotic genomes but the basic structural unit of most telomeres, a repeated minisatellite motif with the general consensus sequence TnAmGo, may vary between eukaryotic groups. Previous studies on several species of green algae revealed that this group exhibits at least two types of telomeric sequences, a presumably ancestral type shared with land plants (Arabidopsis type, TTTAGGG) and conserved in, for example, Ostreococcus and Chlorella species, and a novel type (Chlamydomonas type, TTTTAGGG) identified in Chlamydomonas reinhardtii. We have employed several methodical approaches to survey the diversity of telomeric sequences in a phylogenetically wide array of green algal species, focusing on the order Chlamydomonadales. Our results support the view that the Arabidopsis-type telomeric sequence is ancestral for green algae and has been conserved in most lineages, including Mamiellophyceae, Chlorodendrophyceae, Trebouxiophyceae, Sphaeropleales, and most Chlamydomonadales. However, within the Chlamydomonadales, at least two independent evolutionary changes to the Chlamydomonas type occurred, specifically in a subgroup of the Reinhardtinia clade (including C. reinhardtii and Volvox carteri) and in the Chloromonadinia clade. Furthermore, a complex structure of telomeric repeats, including a mix of the ancestral Arabidopsis-type motifs and derived motifs identical to the human-type telomeric repeats (TTAGGG), was found in the chlamydomonadalean clades Dunaliellinia and Stephanosphaeria. Our results indicate that telomere evolution in green algae, particularly in the order Chlamydomonadales, is far more dynamic and complex than thought before. General implications of our findings for the mode of telomere evolution are discussed.