Miracle-dz/UniFAR-FTUs huggingface dataset:
Shapelet-based sparse image representation for landcover classification of hyperspectral data

This paper presents a novel sparse representation-based classifier for landcover mapping of hyperspectral image data. Each image patch is factorized into segmentation patterns, also called shapelets, and patch-specific spectral features. The combination of both is represented in a patch-specific spatial-spectral dictionary, which is used for a sparse coding procedure for the reconstruction and classification of image patches. Hereby, each image patch is sparsely represented by a linear combination of elements out of the dictionary. The set of shapelets is specifically learned for each image in an unsupervised way in order to capture the image structure. The spectral features are assumed to be the training data. The experiments show that the proposed approach shows superior results in comparison to sparse-representation based classifiers that use no or only limited spatial information and behaves competitive or better than state-of-the-art classifiers utilizing spatial information and kernelized sparse representation-based classifiers.
Low-dose methotrexate enhances cycling of highly anaplastic cancer cells

ABSTRACT We previously showed that cellular RedOx state governs the G1-S transition of AH130 hepatoma, a tumor spontaneously reprogrammed to the embryonic stem cell stage. This transition is impaired when the mithocondrial electron transport system is blocked by specific inhibitors (antimycin A) or the respiratory chain is saturated by adding to the cells high concentrations of pyruvate. The antimycin A or pyruvate block is removed by the addition of adequate concentrations of folate (F). This suggests that the G1-S transition of AH130 cells depends on a respiration-linked step of DNA synthesis related to folate metabolism. In the study reported here, we characterized the effects of methotrexate (MTX), an inhibitor of dihydofolate-reductase, on the G1-S transition of hepatoma cells, in the absence or the presence of exogenously added F, dihydrofolate (FH2) or tetrahydrofolate (FH4). MTX, at 1 μM or higher concentrations, inhibited G1-S transition. This inhibition was completely removed by exogenous folates. Surprisingly, 10 nM MTX stimulated G1-S transition. The addition of F, but not FH2 or FH4, significantly increased this effect. Furthermore, 10 nM MTX removed the block of the G1-S transition operated by antimycin A or pyruvate, an effect which was enhanced in the presence of F. Finally, the stimulatory effect of 10 nM MTX was inhibited in the presence of serine. Our findings indicated that, under certain conditions, MTX may stimulate, rather than inhibiting, the cycling of cancer cells exhibiting a stem cell-like phenotype, such as AH130 cells. This may impact the therapeutic use of MTX and of folates as supportive care.
Disk Brake Squeal: Modeling and Active Control

Considerable effort is spent in the design and testing of disk brakes of modern passenger cars. This effort can be reduced if refined mathematical-mechanical models are used for studying the dynamics of these brakes before prototypes are available. The present paper is devoted to the modeling of a floating caliper disk brake, special regard being given to the suppression of squeal. A simplified model for the dynamics of a floating caliper disk brake is presented. The model includes the brake disk, modeled as a flexible rotating plate, caliper and brake pads. In the model all the prominent features of squeal are reproduced, such as e.g. independence of the frequency on the speed, etc. For a moderately wide frequency range (1-5 kHz) the transverse vibration of the disk plays a significant role in squeal. The pad stiffness and damping coefficient are modeled by distributed nonlinear springs and linear dampers, respectively. In a test rig built in Darmstadt, the model is validated. In addition, the set-up also permits active control of some of the brake's parameters. So far all the experimental results seem to agree very well with our model
Remnant evolution after a carbon–oxygen white dwarf merger

We systematically explore the evolution of the merger of two carbon-oxygen (CO) white dwarfs. The dynamical evolution of a 0.9Msolar + 0.6Msolar CO white dwarf merger is followed by a 3D smoothed particle hydrodynamics (SPH) simulation. The calculation uses a state-of-the-art equation of state that is coupled to an efficient nuclear reaction network that accurately approximates all stages from helium burning up to nuclear statistical equilibrium. We use an elaborate prescription in which artificial viscosity is essentially absent, unless a shock is detected, and a much larger number of SPH particles than earlier calculations. Based on this simulation, we suggest that the central region of the merger remnant can, once it has reached quasi-static equilibrium, be approximated as a differentially rotating CO star, which consists of a slowly rotating cold core and a rapidly rotating hot envelope surrounded by a centrifugally supported disc. We construct a model of the CO remnant that mimics the results of the SPH simulation using a 1D hydrodynamic stellar evolution code and then follow its secular evolution, where we include the effects of rotation on the stellar structure and the transport of angular momentum. The influence of the Keplerian disc is implicitly treated by considering mass accretion from the disc on to the hot envelope. The stellar evolution models indicate that the growth of the cold core is controlled by neutrino cooling at the interface between the core and the hot envelope, and that carbon ignition in the envelope can be avoided despite high effective accretion rates. This result suggests that the assumption of forced accretion of cold matter that was adopted in previous studies of the evolution of double CO white dwarf merger remnants may not be appropriate. Specifically we find that off-centre carbon ignition, which would eventually lead to the collapse of the remnant to a neutron star, can be avoided if the following conditions are satisfied. (1) When the merger remnant reaches quasi-static equilibrium, the local maximum temperature at the interface between the core and the envelope must be lower than the critical limit for carbon ignition. (2) Angular momentum loss from the central merger remnant should not occur on a time-scale shorter than the local neutrino cooling time-scale at the interface. (3) The mass accretion rate from the centrifugally supported disc must be sufficiently low to 10-5Msolaryr-1). Our results imply that at least some products of double CO white dwarfs merger may be considered good candidates for the progenitors of Type Ia supernovae. In this case, the characteristic time delay between the initial dynamical merger and the eventual explosion would be ~105yr.
The truncated splice variants, NT-PGC-1α and PGC-1α4, increase with both endurance and resistance exercise in human skeletal muscle

Recently, a truncated peroxisome proliferator‐activated receptor gamma coactivator‐1 alpha (PGC‐1α) splice variant, PGC‐1α4, that originates from the alternative promoter was shown to be induced by resistance exercise and to elicit muscle hypertrophy without coactivation of “classical” PGC‐1α targets involved in mitochondrial biogenesis and angiogenesis. In order to test if distinct physiological adaptations are characterized by divergent induction of PGC‐1α splice variants, we investigated the expression of truncated and nontruncated PGC‐1α splice variants and PGC‐1α transcripts originating from the alternative and the proximal promoter, in human skeletal muscle in response to endurance and resistance exercise. Both total PGC‐1α and truncated PGC‐1α mRNA expression were increased 2 h after endurance (P < 0.01) and resistance exercise (P < 0.01), with greater increases after endurance exercise (P < 0.05). Expression of nontruncated PGC‐1α increased significantly in both exercise groups (P < 0.01 for both groups) without any significant differences between the groups. Both endurance and resistance exercise induced truncated as well as nontruncated PGC‐1α transcripts from both the alternative and the proximal promoter. Further challenging the hypothesis that induction of distinct PGC‐1α splice variants controls exercise adaptation, both nontruncated and truncated PGC‐1α transcripts were induced in AICAR‐treated human myotubes (P < 0.05). Thus, contrary to our hypothesis, resistance exercise did not specifically induce the truncated forms of PGC‐1α. Induction of truncated PGC‐1α splice variants does not appear to underlie distinct adaptations to resistance versus endurance exercise. Further studies on the existence of numerous splice variants originating from different promoters are needed.
Asymptotically good codes correcting insertions, deletions, and transpositions

A process for producing unsaturated methyl nonadienoate and methyl nonatrienoate monesters useful as precursors for pelargonic acid which comprises contacting, in a reaction inert medium, butadiene and methyl-2,4-pentadienoate in a molar ratio of 2:1 to 10:1 at a temperature of 40 DEG to 120 DEG C. under an inert atmosphere and in the presence of a catalytic amount of a homogeneous palladium (II) complex of the formula wherein R is alkyl, chloroalkyl, bromoalkyl or fluoroalkyl having from 1 to 6 carbon atoms or aryl having 6 to 12 carbon atoms; Q is phosphorous or arsenic and R' is alkyl, aminoalkyl or alkoxy having 1 to 6 carbon atoms or aryl or aryloxy having 6 to 12 carbon atoms. The foregoing precursors may subsequently be hydrogenated to methyl pelargonate (methyl nonanoate) and pelargonic acid may then be obtained by acid-catalyzed hydrolysis of methyl pelargonate.
Zum Wandel im Gebrauch Regionalsprachlicher Lexik

A characteristic feature of vemacular speech and colloquial standard usage (as opposed to traditional dialects and the standard language itself) is their linguistic instability, which makes them susceptible for various forms of contact-induced language change. In an internet survey conducted in 2002, about 1,500 informants from Germany, Austria and Switzerland were asked to comment on eleven selected items from the first two volumes of the Wortatlas der deutschen Umgangssprachen [Atlas of the Colloquial Varieties of German] (WDU 1977/78). A series of new maps was drawn and compared with the WDU maps. The new maps revealed considerable changes in the use of regional lexis. In the present article, most of the changes are interpreted here as result of the convergence and divergence of the various speech communities in the German speaking countries. Some of the findings, however, indicate a noticeable spread of 'southem' variants in the northern Germany, and it is suggested that this development is the result of an increase in the covert prestige of southern German regionalisms.
Critical Role of Airway Macrophages in Modulating Disease Severity during Influenza Virus Infection of Mice

ABSTRACT Airway macrophages provide a first line of host defense against a range of airborne pathogens, including influenza virus. In this study, we show that influenza viruses differ markedly in their abilities to infect murine macrophages in vitro and that infection of macrophages is nonproductive and no infectious virus is released. Virus strain BJx109 (H3N2) infected macrophages with high efficiency and was associated with mild disease following intranasal infection of mice. In contrast, virus strain PR8 (H1N1) was poor in its ability to infect macrophages and highly virulent for mice. Depletion of airway macrophages by clodronate-loaded liposomes led to the development of severe viral pneumonia in BJx109-infected mice but did not modulate disease severity in PR8-infected mice. The severe disease observed in macrophage-depleted mice infected with BJx109 was associated with exacerbated virus replication in the airways, leading to severe airway inflammation, pulmonary edema, and vascular leakage, indicative of lung injury. Thymic atrophy, lymphopenia, and dysregulated cytokine and chemokine production were additional systemic manifestations associated with severe disease. Thus, airway macrophages play a critical role in limiting lung injury and associated disease caused by BJx109. Furthermore, the inability of PR8 to infect airway macrophages may be a critical factor contributing to its virulence for mice.
Low-Rank Approximation and Regression in Input Sparsity Time

We design a new distribution over m × n matrices S so that, for any fixed n × d matrix A of rank r, with probability at least 9/10, ∥SAx∥2 = (1 ± ε)∥Ax∥2 simultaneously for all x ∈ Rd. Here, m is bounded by a polynomial in rε− 1, and the parameter ε ∈ (0, 1]. Such a matrix S is called a subspace embedding. Furthermore, SA can be computed in O(nnz(A)) time, where nnz(A) is the number of nonzero entries of A. This improves over all previous subspace embeddings, for which computing SA required at least Ω(ndlog d) time. We call these S sparse embedding matrices. Using our sparse embedding matrices, we obtain the fastest known algorithms for overconstrained least-squares regression, low-rank approximation, approximating all leverage scores, and ℓp regression. More specifically, let b be an n × 1 vector, ε > 0 a small enough value, and integers k, p ⩾ 1. Our results include the following. —Regression: The regression problem is to find d × 1 vector x′ for which ∥Ax′ − b∥p ⩽ (1 + ε)min x∥Ax − b∥p. For the Euclidean case p = 2, we obtain an algorithm running in O(nnz(A)) + Õ(d3ε −2) time, and another in O(nnz(A)log(1/ε)) + Õ(d3 log (1/ε)) time. (Here, Õ(f) = f ċ log O(1)(f). ) For p ∈ [1, ∞), more generally, we obtain an algorithm running in O(nnz(A) log n) + O(r\ε −1)C time, for a fixed C. —Low-rank approximation: We give an algorithm to obtain a rank-k matrix Âk such that ∥A − Âk∥F ≤ (1 + ε )∥ A − Ak∥F, where Ak is the best rank-k approximation to A. (That is, Ak is the output of principal components analysis, produced by a truncated singular value decomposition, useful for latent semantic indexing and many other statistical problems.) Our algorithm runs in O(nnz(A)) + Õ(nk2ε−4 + k3ε−5) time. —Leverage scores: We give an algorithm to estimate the leverage scores of A, up to a constant factor, in O(nnz(A)log n) + Õ(r3)time.
Supplemental Information The Role of Attention in Figure-Ground Segregation in Areas V 1 and V 4 of the Visual Cortex

1. Figure S1. Position of the electrode arrays in cortex and receptive field locations (related to Figure 2). 2. Figure S2. Time-course of figure-ground modulation in V1 and V4 (related to Figure 4 and 6). 3. Figure S3. Activity in V1 and V4 as function of fixation position (related to Figure 4 and 6). 4. Figure S4. FGM in V1 and V4 as function of the difficulty of the curve-tracing task (related to Figure 4 and 6). 5. Figure S5. FGM in V1 and V4 for trials with fast and slow responses (related to Figure 7). 6. Figure S6. FGM in V1 and V4 in trials with high and low accuracy saccades (related to Figure 7). 7. Figure S7. Schematic drawing of the model architecture and model activity in area V1m (related to Figure 9). 8. Table S1. Model parameters (related to Figure 9).
Tumor Necrosis Factor Improves Vascularization in Osteogenic Grafts Engineered with Human Adipose-Derived Stem/Stromal Cells

The innate immune response following bone injury plays an important role in promoting cellular recruitment, revascularization, and other repair mechanisms. Tumor necrosis factor-α (TNF) is a prominent pro-inflammatory cytokine in this cascade, and has been previously shown to improve bone formation and angiogenesis in a dose- and timing-dependent manner. This ability to positively impact both osteogenesis and vascular growth may benefit bone tissue engineering, as vasculature is essential to maintaining cell viability in large grafts after implantation. Here, we investigated the effects of exogenous TNF on the induction of adipose-derived stem/stromal cells (ASCs) to engineer pre-vascularized osteogenic tissue in vitro with respect to dose, timing, and co-stimulation with other inflammatory mediators. We found that acute (2-day), low-dose exposure to TNF promoted vascularization, whereas higher doses and continuous exposure inhibited vascular growth. Co-stimulation with platelet-derived growth factor (PDGF), another key factor released following bone injury, increased vascular network formation synergistically with TNF. ASC-seeded grafts were then cultured within polycaprolactone-fibrin composite scaffolds and implanted in nude rats for 2 weeks, resulting in further tissue maturation and increased angiogenic ingrowth in TNF-treated grafts. VEGF-A expression levels were significantly higher in TNF-treated grafts immediately prior to implantation, indicating a long-term pro-angiogenic effect. These findings demonstrate that TNF has the potential to promote vasculogenesis in engineered osteogenic grafts both in vitro and in vivo. Thus, modulation and/or recapitulation of the immune response following bone injury may be a beneficial strategy for bone tissue engineering.
Static Upset Characteristics of the 90nm Virtex-4QV FPGAs

Radiation Test Consortium (XRTC) single-event measurements for three of the latest generation of radiation-tolerant reconfigurable FPGAs from Xilinx (90 nm, copper- interconnected, thin-epitaxial CMOS) are presented. Results include proton and heavy-ion upset susceptibilities for unclocked memory elements, high-temperature latchup immunity and a low SEFI rate (e.g., ~one/device-century in geosynchronous orbit).
Scattering by coupled resonating elements in air

Scattering by (a) a single composite scatterer consisting of a concentric arrangement of an outer N-slit rigid cylinder and an inner cylinder which is either rigid or in the form of a thin elastic shell and (b) by a finite periodic array of these scatterers in air has been investigated analytically and through laboratory experiments. The composite scatterer forms a system of coupled resonators and gives rise to multiple low-frequency resonances. The corresponding analytical model employs polar angle dependent boundary conditions on the surface of the N-slit cylinder. The solution inside the slits assumes plane waves. It is shown also that in the low-frequency range the N-slit rigid cylinder can be replaced by an equivalent fluid layer. Further approximations suggest a simple square root dependence of the resonant frequencies on the number of slits and this is confirmed by data. The observed resonant phenomena are associated with Helmholtz-like behaviour of the resonator for which the radius and width of the openings are much smaller than the wavelength. The problem of scattering by a finite periodic array of such coupled resonators in air is solved using multiple scattering techniques. The resulting model predicts band-gap effects resulting from the resonances of the individual composite scatterers below the first Bragg frequency. Predictions and data confirm that use of coupled resonators results in substantial insertion loss peaks related to the resonances within the concentric configuration. In addition, for both scattering problems experimental data, predictions of the analytical approach and predictions of the equivalent fluid layer approximations are compared in the low-frequency interval.
A Differential Equations Approach to Optimizing Regret Trade-offs

We consider the classical question of predicting binary sequences and study the {\em optimal} algorithms for obtaining the best possible regret and payoff functions for this problem. The question turns out to be also equivalent to the problem of optimal trade-offs between the regrets of two experts in an "experts problem", studied before by \cite{kearns-regret}. While, say, a regret of $\Theta(\sqrt{T})$ is known, we argue that it important to ask what is the provably optimal algorithm for this problem --- both because it leads to natural algorithms, as well as because regret is in fact often comparable in magnitude to the final payoffs and hence is a non-negligible term. In the basic setting, the result essentially follows from a classical result of Cover from '65. Here instead, we focus on another standard setting, of time-discounted payoffs, where the final "stopping time" is not specified. We exhibit an explicit characterization of the optimal regret for this setting. To obtain our main result, we show that the optimal payoff functions have to satisfy the Hermite differential equation, and hence are given by the solutions to this equation. It turns out that characterization of the payoff function is qualitatively different from the classical (non-discounted) setting, and, namely, there's essentially a unique optimal solution.
Caveolin-1-Mediated Apolipoprotein A-I Membrane Binding Sites Are Not Required for Cholesterol Efflux

Caveolin-1 (Cav1), a structural protein required for the formation of invaginated membrane domains known as caveolae, has been implicated in cholesterol trafficking and homeostasis. Here we investigated the contribution of Cav1 to apolipoprotein A-I (apoA-I) cell surface binding and intracellular processing using mouse embryonic fibroblasts (MEFs) derived from wild type (WT) or Cav1-deficient (Cav1−/−) animals. We found that cells expressing Cav1 have 2.6-fold more apoA-I binding sites than Cav1−/− cells although these additional binding sites are not associated with detergent-free lipid rafts. Further, Cav1-mediated binding targets apoA-I for internalization and degradation and these processes are not correlated to cholesterol efflux. Despite lower apoA-I binding, cholesterol efflux from Cav1−/− MEFs is 1.7-fold higher than from WT MEFs. Stimulation of ABCA1 expression with an LXR agonist enhances cholesterol efflux from both WT and Cav1−/− cells without increasing apoA-I surface binding or affecting apoA-I processing. Our results indicate that there are at least two independent lipid binding sites for apoA-I; Cav1-mediated apoA-I surface binding and uptake is not linked to cholesterol efflux, indicating that membrane domains other than caveolae regulate ABCA1-mediated cholesterol efflux.
Contributors to Students' use of counselling services in Kenyan Universities

Transition to university life can be stressful for all students. In mitigation, most universities including those in Kenya offer social support to students in form of counselling, financial assistance, health and academic support. Despite this it has been documented that only a minority of university students who experience psychological distress seek professional counselling. This paper looks at contributors to students’ use of counselling services in Kenyan universities. These are classified into four: the social and behavioural issues, academic issues, psychological issues and economic issues. The study applied descriptive survey research design guided by Person Centred and Social Learning Theories. Data was collected using questionnaires, in-depth interview schedules and Focus Group Discussions. The study findings indicate that both male and female students are faced with many counselling issues such as academic, psychological, social, personal, economic, health, physical, vocational and spiritual . It can be concluded that the threat to masculine ideology encourages males to have more positive attitude towards seeking help for academic issues and that female students seek social psychological counselling to help them gain understanding of root causes of their problems. Key words: reasons, social and behavioural issues, academic issues, psychological issues, economic issues