Miracle-dz/UniFAR-FTUs huggingface dataset:
Unsupervised (parameter) learning for MRFs on bipartite graphs

This paper considers unsupervised (parameter) learning for general MRFs on bipartite graphs. That means that we assume training samples which consist of i.i. d. realisations of the field of visible variables only. The variables indexed by the vertices of the other graph part are assumed to be latent. The corresponding learning task is non-trivial because the (log) likelihood is a non-concave function of the model parameters, and, what is worse, its gradient is not tractable. A common approach is to calculate an approximation of the gradient by applying a stochastic gradient method known as “Persistent Contrastive Divergence” [5]. Another option, discussed in [3], is to marginalise over the latent variables (what can be done up to the unknown partition sum) and to maximise the pseudolikelihood for the resulting higher order model directly. Notice however, that the resulting objective function is then no longer concave. The main contribution of this paper is to introduce an alternative learning approach – a modified EM-algorithm with pseudo-likelihood estimator in the M-step, which is tractable on account of the bipartiteness of the model graph. In principle, such a modified EM-algorithm can be applied for parameter learning of arbitrary MRFs [6]. The resulting algorithm will however remain to be intractable, because so is the computation of the posterior pairwise marginal probabilities in the E-step. It is the bipartiteness of the graph, which ensures that the E-step and the M-step of the EM-algorithm are both tractable, if the maximum likelihood estimator in the M-step is replaced by the pseudo-likelihood estimator. MRFs on bipartite graphs can be described as follows. Let (V,E) be an undirected bipartite graph and V1, V2 denote its parts. Let X be a collection of K1-valued random variables indexed by vertices of V1. That is, X = {Xi | i ∈ V1}, where each Xi is a K1-valued random variable. Similarly, Y denotes a collection of K2-valued random variables indexed by vertices of the second part V2. Both co-domains K1 and K2 are assumed finite. We denote realisations of the random field (X ,Y ) by (x,y), i.e. x : V1→ K1 and y : V2→ K2. The joint p.d. of an MRF on (V,E) can be written as an exponential family (assuming strictly positive probability mass)
(q, t)-ANALOGUES AND GLn(Fq) VICTOR REINER AND

We start with a (q, t)-generalization of a binomial coefficient. It can be viewed as a polynomial in t that depends upon an integer q, with combinatorial interpretations when q is a positive integer, and algebraic interpretations when q is the order of a finite field. These (q, t)-binomial coefficients and their interpretations generalize further in two directions, one relating to column-strict tableaux and Macdonald’s “7 variation” of Schur functions, the other relating to permutation statistics and Hilbert series from the invariant theory of GLn(Fq).
No evidence of carbon limitation with tree age and height in Nothofagus pumilio under Mediterranean and temperate climate conditions.

BACKGROUND AND AIMS Trees universally decrease their growth with age. Most explanations for this trend so far support the hypothesis that carbon (C) gain becomes limited with age; though very few studies have directly assessed the relative reductions of C gain and C demand with tree age. It has also been suggested that drought enhances the effect of C gain limitation in trees. Here tests were carried out to determine whether C gain limitation is causing the growth decay with tree age, and whether drought accentuates its effect. METHODS The balance between C gain and C demand across tree age and height ranges was estimated. For this, the concentration of non-structural carbohydrates (NSCs) in stems and roots of trees of different ages and heights was measured in the deciduous temperate species Nothofagus pumilio. An ontogenetic decrease in NSCs indicates support for C limitation. Furthermore, the importance of drought in altering the C balance with ontogeny was assessed by sampling the same species in Mediterranean and humid climate locations in the southern Andes of Chile. Wood density (WD) and stable carbon isotope ratios (δ(13)C) were also determined to examine drought constraints on C gain. KEY RESULTS At both locations, it was effectively found that tree growth ultimately decreased with tree age and height. It was found, however, that NSC concentrations did not decrease with tree age or height when WD was considered, suggesting that C limitation is not the ultimate mechanism causing the age/height-related declining tree growth. δ(13)C decreased with tree age/height at the Mediterranean site only; drought effect increased with tree age/height, but this pattern was not mirrored by the levels of NSCs. CONCLUSIONS The results indicate that concentrations of C storage in N. pumilio trees do not decrease with tree age or height, and that reduced C assimilation due to summer drought does not alter this pattern.
Towards Energy Auto Tuning

Energy efficiency is gaining more and more importance, since well-known ecological reasons lead to rising energy costs. In consequence, energy consumption is now also an important economical criterion. Energy consumption of single hardware resources has been thoroughly optimized for years. Now software becomes the major target of energy optimization. In this paper we introduce an approach called energy auto-tuning (EAT), which optimizes energy efficiency of software systems running on multiple resources. The optimization of more than one resource leads to higher energy savings, because communication costs can be taken into account. E.g., if two components run on the same resource, the communication costs are likely to be less, compared to be running on different resources. The best results can be achieved in heterogeneous environments as different resource characteristics enlarge the synergy effects gainable by our optimization technique. EAT software systems derive all possible distributions of themselves on a given set of hardware resources and reconfigure themselves to achieve the lowest energy consumption possible at any time. In this paper we describe our software architecture to implement EAT.
Ductility and inelastic deformation demands of structures

Current seismic codes require from the seismically designed structures to be capable to withstand inelastic deformation. Many studies dealt with the development of different inelastic spectra with the aim to simplify the evaluation of inelastic deformation and performance of structures. Recently, the concept of inelastic spectra has been adopted in the global scheme of the performance-based seismic design through capacity-spectrum methods. In this paper, the median of the ductility demand ratio for 80 ground motions are presented for different levels of normalized yield strength, defined as the yield strength coefficient divided by the peak ground acceleration (PGA). The influence of the post-to-preyield stiffness ratio on the ductility demand is investigated. For fixed levels of normalized yield strength, the median ductility versus period plots demonstrated that they are independent of the earthquake magnitude and epicentral distance. Determined by regression analysis of the data, two design equations have been developed; one for the ductility demand as function of period, post-to-preyield stiffness ratio, and normalized yield strength, and the other for the inelastic deformation as function of period and peak ground acceleration valid for periods longer than 0.6 seconds. The equations are useful in estimating the ductility and inelastic deformation demands for structures in the preliminary design. It was found that the post-to-preyield stiffness has a negligible effect on the ductility factor if the yield strength coefficient is greater than the PGA of the design ground motion normalized by gravity.
Magnetorheology of dimorphic magnetorheological fluids based on nanofibers

We report a systematic experimental investigation on the use of nanofibers to enhance the magnetorheological (MR) effect in conventional (microsphere-based) MR fluids formulated in polyalphaolefin oil/1-octanol. Two kinds of nanofibers are employed that have very similar morphology but very different magnetic properties. On the one hand we use non-magnetic goethite nanofibers. On the other hand we employ magnetic chromium dioxide nanofibers. For appropriate concentrations the on-state relative yield stress increases up to 80% when incorporating the nanofibers in the formulation. A similar yield stress enhancement is found for both nanofibers investigated (magnetic and non-magnetic) suggesting that the main factor behind this MR enhancement is the particle shape anisotropy. The relative yield stresses obtained by partial substitution of carbonyl iron particles with nanofibers are significantly larger than those measured in previous works on MR fluids formulated by partial substitution with non-magnetic micronsized spherical particles. We also demonstrate that these dimorphic MR fluids also exhibit remarkably larger long-term sedimentation stability while keeping the same penetration and redispersibility characteristics.
Interactive Music: Human Motion Initiated Music Generation Using Skeletal Tracking By Kinect

This work experiments with human motion initiated music generation. Here we present a stand-alone system to tag human motions readily into musical notes. We do this by ﬁrst discovering the human skeleton using depth images acquired by infrared range sensors and then exploiting the resultant skeletal tracking. This real-time skeletal tracking is done using the videogame console Microsoft Kinect TM for Xbox 360. An agent’s bodily motion is deﬁned by the spatial and temporal arrangement of his skeletal framework over the episode of the associated move. After extracting the skeleton of a performing agent by interfacing the Kinect with an intermediate computer application, various features deﬁning the agent’s motion are computed. Features like velocity, acceleration and change in position of the agent’s body parts is then used to generate musical notes. Finally, as a participating agent performs a set of movements in front of our system, the system generates musical notes that are continually regulated by the deﬁned features describing his motion.
Discovery of gene-regulation pathways using local causal search

This paper reports the methods and results of a computer-based algorithm that takes as input the expression levels of a set of genes as given by DNA microarray data, and then searches for causal pathways that represent how the genes regulate each other. The algorithm uses local heuristic search and a Bayesian scoring metric. We applied the algorithm to induce causal networks from a mixture of observational and experimental gene-expression data on genes involved in galactose metabolism in the yeast Saccharomyces cerevisiae. The observational data consisted of gene-expression levels obtained from unmanipulated inverted exclamation mark degrees wild-type inverted exclamation mark +/- cells. The experimental data were produced by deleting ( inverted exclamation mark degrees knocking out inverted exclamation mark +/-) genes and measuring the expression levels of other genes. We used this data to evaluate several variations of the local search method. In each evaluation, causal relationships were predicted for all 36 pairwise combinations of nine key galactose-related genes. These predictions were then compared to the known causal relationships among these genes.
Beclin‐1 Is Required for RANKL‐Induced Osteoclast Differentiation

Beclin‐1 plays a critical role in autophagy; however, it also contributes to other biological processes in a non‐autophagic manner. Although studies have examined the non‐autophagic role of autophagy proteins in the secretory function of osteoclasts (OC), the role of Beclin‐1 is unclear. Here, we examined the role of Beclin‐1 in OC differentiation, and found that mouse bone marrow macrophages (BMMs) showed increased expression of Beclin‐1 upon RANKL stimulation in a p38‐ and NF‐kappa B‐dependent manner. During OC differentiation, Beclin‐1 localized to the mitochondria, where it was involved in the production of mitochondrial intracellular reactive oxygen species. Knockdown of Beclin‐1 in RANKL‐primed BMMs led to a significant reduction in RANKL‐dependent osteoclastogenesis, which was accompanied by reduced NFATc1 induction. Furthermore, knockdown of Beclin‐1 inhibited RANKL‐mediated activation of JNK and p38, both of which act downstream of reactive oxygen species, resulting in the suppression of NFATc1 induction. Finally, overexpression of constitutively active NFATc1 rescued the phenotype induced by Beclin‐1 knockdown, indicating that Beclin‐1 mediates RANKL‐induced osteoclastogenesis by regulating NFATc1 expression. These findings show that Beclin‐1 plays a non‐autophagic role in RANKL‐induced osteoclastogenesis by inducing the production of reactive oxygen species and NFATc1. J. Cell. Physiol. 229: 1963–1971, 2014. © 2014 Wiley Periodicals, Inc.
Elastic, Dielectric and Piezoelctric Coefficients of Domain Engineered 0.70Pb(Mg1/3Nb2/3)O3‐0.30PbTiO3 Single Crystal

A complete set of elastic, dielectric and piezoelectric coefficients for the domain engineered 0.70Pb(Mg1/3Nb2/3)O3‐0.30PbTiO3 [PMN‐30%PT] single crystal was measured by a hybrid method combining ultrasonic and resonance techniques. At room temperature, the PMN‐30%PT single crystal has rhombohedral symmetry. After being poled along [001] of the cubic axes, four degenerate domain states are present, which means that the system is macroscopically pseudotetragonal. The complete data set of material constants was determined for this domain engineered system based on the effective tetragonal 4mm symmetry. The sources of experimental errors and the error propagation for derived constants were analyzed in detail. Based on the analysis, an improved characterization scheme was formulated to minimize the relative errors of derived constants. In this optimized scheme, the elastic stiffness coefficients under constant electric field cijE , piezoelectric stress coefficients dij and dielectric permittivities under cons.
Socioeconomic inequalities in survival and provision of neonatal care: population based study of very preterm infants

Objectives To assess socioeconomic inequalities in survival and provision of neonatal care among very preterm infants. Design Prospective cohort study in a geographically defined population. Setting Former Trent health region of the United Kingdom (covering about a twelfth of UK births). Participants All infants born between 22+0 and 32+6 weeks’ gestation from 1 January 1998 to 31 December 2007 who were alive at the onset of labour and followed until discharge from neonatal care. Main outcome measures Survival to discharge from neonatal care per 1000 total births and per 1000 very preterm births. Neonatal care provision for very preterm infants surviving to discharge measured with length of stay, provision of ventilation, and respiratory support. Deprivation measured with the UK index of multiple deprivation 2004 score at super output area level. Results 7449 very preterm singleton infants were born in the 10 year period. The incidence of very preterm birth was nearly twice as high in the most deprived areas compared with the least deprived areas. Consequently rates of mortality due to very preterm birth per 1000 total births were almost twice as high in the most deprived areas compared with the least deprived (incidence rate ratio 1.94, 95% confidence interval 1.62 to 2.32). Mortality rates per 1000 very preterm births, however, showed little variation across all deprivation fifths (incidence rate ratio for most deprived fifth versus least deprived 1.02, 0.86 to 1.20). For infants surviving to discharge from neonatal care, measures of length of stay and provision of ventilation and respiratory support were similar across all deprivation fifths. Conclusions The burden of mortality and morbidity is greater among babies born to women from deprived areas because of increased rates of very preterm birth. After very preterm birth, however, survival rates and neonatal care provision is similar for infants from all areas.
Kinetics of the receptor current in bullfrog saccular hair cells

The receptor current of hair cells from the bullfrog's sacculus was measured by voltage clamp recording across the isolated sensory epithelium. Several hundred hair cells were stimulated en masse by moving the overlying otolithic membrane with a piezoelectrically activated probe. As measured by optical recording of otolithic membrane motion, the step displacement stimuli reached their final amplitudes of up to 1 micrometer within 100 microseconds. The relationship between displacement and steady-state receptor current is an asymmetric, sigmoidal curve about 0.5 micrometer in extent. The time constant of the approach to steady state depends upon the magnitude of the hair bundle displacement and ranges from 100 to 500 microseconds at 4 degrees C; the time course is faster with larger displacements or at higher temperatures. Both the displacement-response curve and the kinetics of the response are changed by alterations in the Ca2+ concentration at the apical surface of the cells. The characteristics of the response are not consistent with simple models for the transduction process that involve enzymatic regulation of channel proteins or diffusible second messengers. Mechanical stimulation is instead posited to act directly by altering the free energy difference between the open and closed forms of the transduction channel, thereby inducing a redistribution between these states. The dependences of the response kinetics on displacement and on temperature suggest that the thermal interconversion between open and closed transduction channels is limited by an enthalpy of activation of about 12 kcal/mol.
Combined Effects of Viscosity Variation and Surface Roughness on the Squeeze Film Lubrication of Journal Bearings with Micropolar Fluids

In this paper, a theoretical study of the combined effects of viscosity variation and surface roughness on the squeeze film performance of journal bearings lubricated with micropolar fluid is made. The modified averaged Reynolds equation for micropolar fluids accounting for the randomized surface roughness structure and variation of viscosity is mathematically derived. The Christensen’s stochastic theory for hydrodynamic lubrication of rough surfaces is used to study the effect of two types of one dimensional surface roughness patterns on the squeeze film characteristics of a journal bearing with micropolar fluid. Closed form expressions for the mean pressure load carrying capacity are obtained for the infinitely short journal bearing. It is observed that, the transverse surface roughness pattern improves the squeeze film characteristics where as the adverse effects are observed for the one-dimensional longitudinal surface roughness pattern. The effect of variation of viscosity in micropolar fluid on the squeeze film characteristic of rough short journal bearings is analyzed.
NP-Hardness of Reed-Solomon Decoding and the Prouhet-Tarry-Escott Problem

Establishing the complexity of Bounded Distance Decoding for Reed-Solomon codes is a fundamental open problem in coding theory, explicitly asked by Guruswami and Vardy (IEEE Trans. Inf. Theory, 2005). The problem is motivated by the large current gap between the regime when it is NP-hard, and the regime when it is efficiently solvable (i.e., the Johnson radius). We show the first NP-hardness results for asymptotically smaller decoding radii than the maximum likelihood decoding radius of Guruswami and Vardy. Specifically, for Reed-Solomon codes of length N and dimension K = O(N), we show that it is NP-hard to decode more than N-K-O/log N log log N) errors. Moreover, we show that the problem is NP-hard under quasipolynomial-time reductions for an error amount > N-K-c log N (with c > 0 an absolute constant). An alternative natural reformulation of the Bounded Distance Decoding problem for Reed-Solomon codes is as a Polynomial Reconstruction problem. In this view, our results show that it is NP-hard to decide whether there exists a degree K polynomial passing through K + O(log N / log log N) points from a given set of points (a1, b1), (a2, b2) . , (aN, bN). Furthermore, it is NP-hard under quasipolynomial-time reductions to decide whether there is a degree K polynomial passing through K + c log N many points (with c > 0 an absolute constant). These results follow from the NP-hardness of a generalization of the classical Subset Sum problem to higher moments, called Moments Subset Sum, which has been a known open problem, and which may be of independent interest. We further reveal a strong connection with the well-studied Prouhet-Tarry-Escott problem in Number Theory, which turns out to capture a main barrier in extending our techniques. We believe the Prouhet-Tarry-Escott problem deserves further study in the theoretical computer science community.
The performance of quantum dots-based white light-emitting diodes

Recently, the investigation of quantum dots (QDs) as a color converter for white light-emitting diodes (WLEDs) application has attracted a great deal of attention. Because the narrow emission wavelength of QDs can be controlled by their particle sizes and compositions, which is facilitated to improve the color gamut of display as well as color rendering index (CRI) and the correlated color temperature (CCT) of WLEDs. In a typical commercially available LCD display, the color gamut is approximately to 75 % which is defined by the National Television System Committee (NTSC). In order to enhance NTSC, the full width at half-maximum (FWHM) of color converter should be less than 30 nm. Therefore, the QDs are the best choice for display application due to the FWHM of QDs is meet the demand of display application. In this study, the hot injection method with one-pot process is used to synthesis of colloidal ternary ZnCdSe green (G-) and red-emission (R-) QDs with a narrow emission wavelength around 537 and 610 nm. By controlling the complex reagents-stearic acid (SA) and lauric acid (LA), high performance of G- and R-QDs can be prepared. The quantum yields (QYs), particle sizes and FWHM for G- and R-QDs are 70, 30 %, 3.2 ± 0.5, 4.1 ± 0.5 nm and 25, 26 nm, respectively. In order to explore the performance of QDs-based WLEDs, mixing ratios effect between G-QD and R-QD are studied and the WLED is packed as conformal-type. Different ratios of R-QD and G-QD (1:10, 1:20 and 1:30) are mixed and fill up the 3020 SMD blue-InGaN LED, and named as LED-10, LED-20 and LED-30. After that, UV curable gel is deposited on the top of QD layer to form WLED and named as LED-10*, LED-20* and LED-30*. The results show that the Commission International d’Eclairage (CIE) chromaticity coordinates, color rendering index (CRI), luminous efficacy of LED-10*, LED-20* and LED-30* are (0.27, 0.21), 53, 1.9 lm/W, (0.29, 0.30), 72, 3.3 lm/W and (0.25, 0.34), 45, 6.8 lm/W, respectively. We can find that the positions of CIE can be controlled simply by adjusting the ratios of G- and R-QDs. Besides, the LED-10 and LED-20* device shows the high CRI, implying that it has great potential for application on backlight of display technology and solid-state lighting.