Miracle-dz/UniFAR-FTUs huggingface dataset:
Spreading waves of decreased diffusion coefficient lifter cortical stimulation in the rat brain

A method is demonstrated for the noninvasive detection and study of spreading cortical depression. Spreading depression (SD) was elicited in rats by topical application of potassium chloride to the exposed cortex. The apparent diffusion coefficient (Dapp) of water in a region of the cortex, measured using a PFG‐NMR spin echo sequence with an observation time of 40 ms, declines 35% within 30 s and recovers to the normal value within the next 30 s. The region of decreased Dapp was shown to be 2 mm in size and to move in the cortex, away from the point of application, with a uniform velocity of 3.3 ± 0.5 mm/min. The behavior of the affected region is consistent with other reports of the behavior of SD as monitored by electro‐physiological means. The technique can be implemented on currently available MRI equipment and makes possible the noninvasive study of SD in animal models of neurological disorders, their therapeutic intervention, and possibly the study of SD in humans.
Collaborative Cell-Resistant Properties of Polyelectrolyte Multilayer Films and Surface PEGylation on Reducing Cell Adhesion to Cytophilic Surfaces

Both poly(ethylene glycol) (PEG) grafting and layer-by-layer polyelectrolyte multilayer (PEM) deposition for surface modification of biomaterials have been shown to decrease cell adhesion. The aim of this study was to investigate the synergic efficacy of PEGylated PEM films on reducing cell adhesion. PEG grafted to poly(ethylene imine) (PEI) was deposited onto the top of PEI/PAA (poly(acrylic acid)) multilayer films which were deposited onto cytophilic substrates, including tissue culture polystyrene and collagen-based substrate. The efficacy of the PEGylated PEM films in blocking adhesion of L929 cells was investigated by varying the amount of conjugated PEG and the layer numbers of PEM films. We found that cell adhesion was reduced on the swollen PEM films and further decreased by deposition of PEI-g-PEG as the topmost layer. The ability in cell resistance was enhanced with increasing PEG contents of PEGylated PEM films. PEGylated PEM films were stable for long-term incubation in phosphate-buffered saline. We demonstrated that cell affinity of cytophilic surfaces could be depressed by deposition of PEGylated PEM films.
A heuristic approach to the formulas for population attributable fraction

BACKGROUND As the definitional formula for population attributable fraction is not usually directly usable in applications, separate estimation formulas are required. However, most epidemiology textbooks limit their coverage to Levin's formula, based on the (dichotomous) distribution of the exposure of interest in the population. Few present or explain Miettinen's formula, based on the distribution of the exposure in the cases; and even fewer present the corresponding formulas for situations with more than two levels of exposure. Thus, many health researchers and public health practitioners are unaware of, or are not confident in their use of, these formulas, particularly when they involve several exposure levels, or confounding factors. METHODS/RESULTS A heuristic approach, coupled with pictorial representations, is offered to help understand and interconnect the structures behind the Levin and Miettinen formulas. The pictorial representation shows how to deal correctly with several exposure levels, and why a commonly used approach is incorrect. Correct and incorrect approaches are also presented for situations where estimates must be aggregated over strata of a confounding factor.
Landscape-scale changes in forest structure and functional traits along an Andes-to-Amazon elevation gradient

Abstract. Elevation gradients provide opportunities to explore environmental controls on forest structure and functioning. We used airborne imaging spectroscopy and lidar (light detection and ranging) to quantify changes in three-dimensional forest structure and canopy functional traits in twenty 25 ha landscapes distributed along a 3300 m elevation gradient from lowland Amazonia to treeline in the Peruvian Andes. Elevation was positively correlated with lidar-estimated canopy gap density and understory vegetation cover, and negatively related to canopy height and the vertical partitioning of vegetation in canopies. Increases in canopy gap density were tightly linked to increases in understory plant cover, and larger gaps (20–200 m2) produced 25–30 times the response in understory cover than did smaller gaps (
Neuronal transients

A recent letter to Nature (Vaadia et al. Nature, Lond. 373, 515-518 (1995)) presented compelling results concerning neuronal interactions in monkey cortex. Vaadia et al. made two fundamental points: (i) it is possible that cortical function is mediated by dynamic modulation of coherent firing among neurons; and (ii) these time-dependent changes in correlations can emerge without modulation of firing rates. These observations have severe implications for models of neural coding and empirical approaches that are based on firing rates (e. g. neuroimaging). This communication presents a simpler explanation for the results presented in Vaadia et al., by noting they are consistent with the correlated expression of stereotyped neuronal transients following (or preceding) a salient event. This re-formulation is important because: (i) correlations measured in terms of transients are not time-dependent, allowing prevailing models of neural coding to be ‘reinstated’; and (ii) it suggests a powerful analysis based on singular value decomposition of firing rates.
Induction of Adhesion/Differentiation of Human Neuroblastoma Cells by Tumour Necrosis Factor‐α Requires the Expression of an Inducible Nitric Oxide Synthase

Neuroblastoma cell lines (SK‐N‐SH and SK‐N‐MC) were induced to differentiate, as detected by the expression of neurofilament proteins of 68 and 200 kDa, and to express adhesion molecules (intercellular adhesion molecule‐1 and vascular cell adhesion molecule) after stimulation with tumour necrosis factor‐α (TNF‐α). This induction was accompanied by the arrest of cell growth. The induction of neuroblastoma adhesion by TNF‐α could be inhibited by the nitric oxide synthase inhibitors, L‐N‐monomethyl arginine (L‐NMMA) and L‐N6‐(1–imidoethyl)‐lysine (highly specific for the inducible enzyme), but not by the inactive enantiomer D‐NMMA. These results indicate that TNF‐α induces the adhesion of neuroblastoma cells via nitric oxide. This was confirmed by the finding that the adhesion/differentiation of SK‐N‐SH and SK‐N‐MC cells can be directly induced by the addition of nitric oxide donors, sodium nitroprusside and S‐nitroso‐N ‐acetyl‐penicillamine, into the culture medium. The isoform of the nitric oxide synthase induced in human neuroblastoma cells by TNF‐α treatment was identified enzymatically as isoform II by Western blotting and by the polymerase chain reaction. Thus TNF‐α induces the in vitro adhesion/differentiation of human neuroblastoma cells through nitric oxide synthesized by a calcium‐independent inducible form of nitric oxide synthase, clearly indicating that isoform II of nitric oxide synthase can be expressed in human neuronal cell types.
Quality and Safety in Health Care, Part I: Five Pioneers in Quality

Abstract Five pioneers had a huge impact on the quality movement in health care in the United States. Ernest Codman contributed in many ways, including his focus on outcome analysis. Avidis Donabedian is known for his focus on the 3 domains of structure, process, and outcome in health care. Walter Shewhart is known especially for the control chart and early work on what W. Edwards Deming made into the PDSA cycle. Deming is also known for other contributions, including his 14 points of management, correcting system problems rather than blaming the workers, and his System of Profound Knowledge. Juran is known for the Pareto principle and his emphasis on customer satisfaction and addressing the human, not just statistical side, of quality improvement.
Inhibition of retinal and choroidal neovascularization by a novel KDR kinase inhibitor.

PURPOSE Inhibition of vascular endothelial growth factor (VEGF) signaling has shown great promise for the treatment of ocular neovascular disease. Current anti-VEGF therapies in late-stage development, while efficacious, require dosing by frequent intravitreal injections that are inconvenient to patients. VEGF signaling inhibitors that demonstrate more convenient dosing regimens could lead to the improved treatment of neovascular diseases such as wet age related macular degeneration (AMD) and proliferative diabetic retinopathy (PDR). Here we describe the assessment of a KDR (VEGFR2) kinase inhibitor in two well-established models of ocular neovascularization following oral administration. METHODS A novel KDR kinase inhibitor was dosed by oral gavage for 12 days at 0, 10, 30, or 100 mg/kg in an adult male Brown Norway rat laser induced choroidal neovascularization (CNV) model. The areas of CNV lesions were quantitated by fluorescence image analysis of FITC-dextran perfused animals. The kinase inhibitor was also assessed in a rat oxygen induced retinopathy (OIR) model in which neonatal rats were placed in an oxygen chamber that delivered alternating 24 h cycles of 50% and 10% oxygen for 14 days. After 14 days of oxygen treatment, the animals were returned to room air and dosed orally for 7 days with 0, 10, or 30 mg/kg kinase inhibitor. The extent of retinal neovascularization was assessed by counting pre-retinal neovascular nuclei on histological sections. RESULTS At doses of 100 mg/kg, the KDR kinase inhibitor resulted in a 98% reduction in lesion size in the rat CNV model. 30 mg/kg doses of the inhibitor showed a 70% and 80% reduction in lesion size in the laser CNV and OIR models, respectively. CONCLUSIONS Oral dosing of the described KDR kinase inhibitor effectively inhibits neovascularization in two well-established animal models of ocular neovascularization. These data suggest that compounds of this class may prove to be useful for the treatment of a variety of ocular neovascular diseases using a convenient oral dosing regimen.
How Do Accounting Variables Explain Stock Price Movements? Theory and Evidence

This paper provides theory and evidence showing how accounting variables explain cross-sectional stock returns. Based on Zhang (2000), who relates equity value to accounting measures of underlying operations, we derive returns as a function of earnings yield, equity capital investment, and changes in profitability, growth opportunities and discount rates. Empirical results confirm the predicted roles of all identified factors. The model explains about 20% of the cross-sectional return variation, with cash-flow-related factors (as opposed to changes in discount rates) accounting for most of the explanatory power. The properties of the model are robust across various subsamples and periods.
Weak Interest Rate Parity and Currency Portfolio Diversification

This paper presents a dynamic model of optimal currency returns with a hidden Markov regime switching process. We postulate a weak form of interest rate parity that the hedged risk premiums on currency investments are identical within each regime across all currencies. Both the in-sample and the out-of-sample data during January 2002 - March 2005 strongly support this hypothesis. Observing past asset returns, investors infer the prevailing regime of the economy and determine the most likely future direction to facilitate portfolio decisions. Using standard mean variance analysis, we find that an optimal portfolio resembles the Federal Exchange Rate Index which characterizes the strength of the U.S. dollar against world major currencies. The similarity provides a strong implication that our three-regime switching modelis appropriate for modeling the hedged returns in excess of the U.S. risk free interest rate. To investigate the impact of the equity market performance on changes of exchange rates, we include the S&P500 index return as an exogenous factor for parameter estimation.
Soluble antigens obtained from influenza virus by treatment with non-ionic detergent

Summary Highly purified influenza virus was degraded using anionic and non-ionic detergents. Best results were obtained using the non-ionic detergent Triton N101. Tests showed that virus extracts contained neuraminidase and a substance that reacted specifically with rabbit antibody to virus haemagglutinin (specific serum blocking substance). Haemagglutination-inhibiting antibody was produced when virus extracts were inoculated into guinea-pigs. Immunodiffusion tests showed that extracts were complex. Host-specific material was regularly found. Under appropriate conditions S-antigen was detected as a single line pattern component. Two or more virus-specific materials were also present. One of these was probably neuraminidase and the other the specific serum blocking substance.
Poisson Trust Factorization for Incorporating Social Networks into Personalized Item Recommendation

Many web users are faced with the problem of selecting which books to read and movies to watch. Traditionally, we ask our trusted friends for recommendations, but algorithmic recommendation models make those choices even easier, saving us time and effort by steering us towards media we are more likely to enjoy. The downside to most algorithmic recommendations is that, for some people, part of the appeal of reading or consuming other media is in creating shared experiences with friends. In this work, we aim to bridge this gap. We present a model that incorporates social network information into recommendation models, reintroducing the social aspect to recommendation and having the potential to improve overall recommendations. Further, our model discovers the latent trust that exists between users in a network and allows us to consider which users are more trustworthy than others, providing us insight into the social network’s dynamics.
All-Pairs 2-Reachability in O(n^w log n) Time

In the 2-reachability problem we are given a directed graph G and we wish to determine if there are two (edge or vertex) disjoint paths from u to v, for given pair of vertices u and v. In this paper, we present an algorithm that computes 2-reachability information for all pairs of vertices in O(n^w log n) time, where n is the number of vertices and w is the matrix multiplication exponent. Hence, we show that the running time of all-pairs 2-reachability is only within a log factor of transitive closure. Moreover, our algorithm produces a witness (i.e., a separating edge or a separating vertex) for all pair of vertices where 2-reachability does not hold. By processing these witnesses, we can compute all the edge- and vertex-dominator trees of G in O(n^2) additional time, which in turn enables us to answer various connectivity queries in O(1) time. For instance, we can test in constant time if there is a path from u to v avoiding an edge e, for any pair of query vertices u and v, and any query edge e, or if there is a path from u to v avoiding a vertex w, for any query vertices u, v, and w.
High Sensitive Piezoresistive Cantilever MEMS Based Sensor by Introducing Stress Concentration Region (SCR)

© 2012 Firdaus et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. High Sensitive Piezoresistive Cantilever MEMS Based Sensor by Introducing Stress Concentration Region (SCR)
Pollen limitation and reproduction varies with population size in experimental populations of Sabatia angularis (Gentianaceae).

Individuals in large plant populations are expected to benefit from increased reproductive success relative to those in small populations because of the facilitative effects of large aggregations on pollination. As populations become small, the inability to attract sufficient numbers of pollinators can reduce reproduction via pollen limitation. This study experimentally tested whether such trends occur for the herbaceous biennial Sabatia angularis (L.) Pursh (Gentianaceae). We created artificial populations of varying size consisting of potted S. angularis plants in two field sites to determine whether population size affected mean fruit and seed set. We also examined whether population size affected the degree of pollen limitation using a supplemental pollination design in one of the sites. Our results showed that, on average, seed set was lower in large populations, not small populations, of S. angularis and that this result may be due to increased pollen limitation in large populations. We suggest that.
Genetic evidence for wide distribution of the alien prawn-goby, Vanderhorstia mertensi (Actinopterygii: Perciformes: Gobiidae), along the northeast mediterranean.

Vanderhorstia mertensi Klausewitz, 1974, is a recently acknowledged alien fish in the Mediterranean Sea, hitherto observed only from Fethiye Bay, Turkey. To explore its distribution, trawl bycatch from eastern Antalya and Iskenderun was examined and an underwater survey was performed off Kas (western Antalya). An established pop - ulation was found off Guvercin Island, Kas, and six specimens were identified from trawl bycatch collected off Antalya and Iskenderun. The trawl-collected specimens were badly damaged and identification was made possible by the analysis of their 16S rDNA sequences. Our findings suggest that the species was only recently introduced and its population size has increased rapidly. Symbiotic relationship with alpheids (Apheidae, Crustacea) may have enhanced this prawn-goby's establishment and dispersal along the Mediterranean coast of Turkey.
Grid-dispersion error reduction for broadband FDTD electromagnetic simulations

We introduce a general procedure to reduce grid (numerical) dispersion error in broadband finite-difference time-domain (FDTD) simulations based on dispersion filters. Dispersion error functionals are first expanded in a Taylor series that, for a broadband signal, produces larger dispersion errors for the high-frequency components of the signal. By a change of polynomial basis, modified FDTD update coefficients are obtained in order to minimize the dispersion error over some preassigned frequency band. Moreover, desirable properties such as a local dispersion error that decreases within a frequency band can also be attained. In particular, Butterworth (maximally flat) or Chebyshev polynomial expansions (filters) are considered along with their application toward the optimization of two recently developed high-order FDTD schemes.
Frequency estimation of distorted power system signals using extended complex Kalman filter

The paper proposes an extended complex Kalman filter and employs it for the estimation of power system frequency in the presence of random noise and distortions. From the discrete values of the 3-phase voltage signals of a power system, a complex voltage vector is formed using the well known /spl alpha//spl beta/-transform. A nonlinear state space formulation is then obtained for this complex signal and an extended Kalman filtering approach is used to compute the true state of the model iteratively with significant noise and harmonic distortions. As the frequency is modeled as a state, the estimation of the state vector yields the unknown power system frequency. Several computer simulations test results are presented in the paper to highlight the usefulness of this approach in estimating near nominal and off-nominal power system frequencies.
Discrimination Between Atrial Fibrillation ( AF ) & Normal Sinus Rhythm ( NSR ) Using Linear Parameters

Heart rate analysis method can be used for discern between atrial fibrillation (AF) and Normal Synus Rhythm (NSR). Atrial fibrillation is one of the common sustained cardiac arrhythmia diagnose by electrocardiogram (ECG). The Heart rate variability (HRV) and standard measurements techniques are used to detect QRS Complexes from ECG. All R peaks are detected for RR intervals. Various parameters can be measured using linear indexes of HRV like SDNN, SDANN, RMSSD, PNN50, LF, HF, VLF etc. It classifies NSR and AF patients using spectral parameter LF/HF ratio.
Augmenting sampling based controllers with machine learning

Efficient learning of 3D character control still remains an open problem despite of the remarkable recent advances in the field. We propose a new algorithm that combines planning by a sampling-based model-predictive controller and learning from the planned control, which is very noisy. We combine two methods of learning: 1) immediate but imprecise nearest-neighbor learning, and 2) slower but more precise neural net-work learning. The nearest neighbor learning allows to rapidly latch on to new experiences whilst the neural net-work learns more gradually and develops a stable representation of the data. Our experiments indicate that the learners augment each other, and allow rapid discovery and refinement of complex skills such as 3D bipedal locomotion. We demonstrate this in locomotion of 1-, 2- and 4-legged 3D characters under disturbances such as heavy projectile hits and abruptly changing target direction. When augmented with the learners, the sampling based model predictive controller can produce these stable gaits in under a minute on a 4-core CPU. During training the system runs real-time or at interactive frame rates depending on the character complexity.
Three different regulatory mechanisms enable yeast hexose transporter (HXT) genes to be induced by different levels of glucose

The HXT genes (HXT1 to HXT4) of the yeast Saccharomyces cerevisiae encode hexose transporters. We found that transcription of these genes is induced 10- to 300-fold by glucose. Analysis of glucose induction of HXT gene expression revealed three types of regulation: (i) induction by glucose independent of sugar concentration (HXT3); (ii) induction by low levels of glucose and repression at high glucose concentrations (HXT2 and HXT4); and (iii) induction only at high glucose concentrations (HXT1). The lack of expression of all four HXT genes in the absence of glucose is due to a repression mechanism that requires Rgt1p and Ssn6p. GRR1 seems to encode a positive regulator of HXT expression, since grr1 mutants are defective in glucose induction of all four HXT genes. Mutations in RGT1 suppress the defect in HXT expression caused by grr1 mutations, leading us to propose that glucose induces HXT expression by activating Grr1p, which inhibits the function of the Rgt1p repressor. HXT1 expression is also induced by high glucose levels through another regulatory mechanism: rgt1 mutants still require high levels of glucose for maximal induction of HXT1 expression. The lack of induction of HXT2 and HXT4 expression on high levels of glucose is due to glucose repression: these genes become induced at high glucose concentrations in glucose repression mutants (hxk2, reg1, ssn6, tup1, or mig1). Components of the glucose repression pathway (Hxk2p and Reg1p) are also required for generation of the high-level glucose induction signal for expression of the HXT1 gene. Thus, the glucose repression and glucose induction mechanisms share some of the same components and may share the same primary signal generated from glucose.