Miracle-dz/UniFAR-FTUs huggingface dataset:
Coordinated Standoff Tracking of Moving Targets: Control Laws and Information Architectures

In this paper, we present work on control of autonomous vehicle formations in the context of the coordinated stando tracking problem . The objective is to use a team of unmanned aircraft to fly a circular orbit around a moving target with prescribed inter-vehicle angular spacing using only local information. We use the recently introduced Lyapunov guidance vector field approach to achieve the desired circular trajectory. The contributions of this paper involve both single vehicle path planning and multiple vehicle coordination. For single vehicle path planning, we complete a proof of heading convergence using feedback, which has thus far not been fully addressed in the literature, and also oer a novel approach for heading convergence that does not require continuous feedback in the ideal case (no wind, stationary target), taking advantage of an analytical solution to the guidance field. Further, we use a variable airspeed controller to maintain the circular trajectory despite unknown wind and unknown constant velocity target motion. Adaptive estimates of the unknown wind and target motion are introduced to ensure stability to the circular trajectory. A novel feature of our results is rigorous satisfaction of vehicle specific kinematic constraints on heading rates and airspeed variations. For multiple vehicle coordination, we again use a variable airspeed controller to achieve the prescribed angular spacing. In an eort towards a unified framework for control of autonomous vehicle formations, we make a connection with some recent work that addresses information architecture in vehicle formations using graph theory. Specifically, we utilize two types of information architectures, symmetric and asymmetric, and implement decentralized control laws. The information architectures are scalable in the sense that the number of required communication/sensing links increases linearly with the number of vehicles. The control laws are decentralized in the sense that they use only local information.
Effects of Estrogens on the Expression of Caveolin-1 in the Urinary Bladders of Female Rats

Purpose The purposes of this study were to investigate the effect of hormonal alterations on the expression of caveolin-1 in the urinary bladders of ovariectomized rats and to determine the role of caveolin-1 in the overactivity of the detrusor muscle that occurs with hormonal alterations in rats. Methods Female Sprague-Dawley rats were divided into three groups: a control group, a group that underwent bilateral ovariectomy (Ovx), and a group that underwent bilateral ovariectomy followed by subcutaneous injections of 17β-estradiol (Ovx+Est). After 4 weeks, urodynamic studies were done to measure the contraction interval and contraction pressure. The expression and cellular localization of caveolin-1 were determined by Western blot and immunofluorescence in the urinary bladders of rats. Results On cystometrograms, the contraction interval was significantly shorter in the Ovx group (3.0±0.3 minute) than in the control group (5.6±0.5 minute) but was longer in the Ovx+Est group (9.2±0.4 minute) (P<0.05). Conversely, the average contraction pressure was higher in the Ovx group (26.4±0.48 mmHg) than in the control group (21.8±0.37 mmHg) but was lower in the Ovx+Est group (23.9±0.76 mmHg) (P<0.05). Caveolin-1 was expressed in the capillaries, arterioles, and venules. Expression of the protein caveolin-1 was significantly lower after ovariectomy and was restored to control levels after treatment with 17β-estradiol (P<0.05). Conclusions Hormonal alterations cause a significant change in the expression of caveolin-1, which suggests that caveolin-1 might have a functional role in the overactivity of the detrusor muscle related to hormonal alterations in the urinary bladders of rats.
Finite-Time Approximate Consensus and Its Application to Distributed Frequency Regulation in Islanded AC Microgrids

In this paper, we propose an iterative algorithm that allows a set of interconnected nodes to reach approximate consensus in a finite number of steps, i.e., Allows the nodes to reach agreement to within a pre-specified bound in finite time. While this algorithm could be used in many applications, we discuss it within the context of a distributed control architecture for frequency regulation in islanded AC micro grids. Our approach to achieving finite-time approximate consensus builds upon ratio consensus, a distributed iterative algorithm in which each node maintains two state variables where the ratio of the states converges asymptotically to a constant that is equal for all the nodes. Simulation results illustrating the operation of our proposed algorithm for two networks are included.
Quegel: A General-Purpose System for Querying Big Graphs

Inspired by Google's Pregel, many distributed graph processing systems have been developed recently to process big graphs. These systems expose a vertex-centric programming interface to users, where a programmer thinks like a vertex when designing parallel graph algorithms. However, existing systems are designed for tasks where most vertices in a graph participate in the computation, and they are not suitable for processing light-workload graph queries which only access a small portion of vertices. This is because their programming model can seriously under-utilize the resources in a cluster for processing graph queries. In this demonstration, we introduce a general-purpose system for querying big graphs, called Quegel, which treats queries as first-class citizens in the design of its computing model. Quegel adopts a novel superstep-sharing execution model to overcome the weaknesses of existing systems. We demonstrate it is user-friendly to write parallel graph-querying programs with Quegel's interface; and we also show that Quegel is able to achieve real-time response time in various applications, including the two applications that we plan to demonstrate: point-to-point shortest-path queries and XML keyword search.
Partially Replacement of Portland Cement with Rice Husk Ash in Concrete

Concrete is a site made material unlike other materials of construction and as such can vary to a very great extent in its quality, properties and performance owing to the use of natural materials except cement. From materials of varying properties, to may concrete of stipulated qualities, an intimate knowledge of the inter-action of various ingredients that in to the making of concrete is required to be known both in the plastic condition and in the hardened condition. Rice husk is an agriculture by-product generated from peddy. Presently there are limited uses of rice husk and unused quantity is dumped unattended in the landfills, which create pollution in the environment. In this study, characterization of rice husk ash was carried out to evaluate its engineering properties. The cements were replaced partially by rice husk ash in two grades of concrete i.e. M20 by 0%,5% 10%,15% and 20%,rice husk ash, by weight. The slump, compressive strength and flexural strength tests were conducted and results were analyzed. Keywords— Component; formatting; style; styling; insert (key words)
1 Gyr in the life of the globular cluster NGC 6397

ABSTRACT M4 and NGC 6397 are two very similar galactic globular clusters, which differ mainly intheir surface brightness proﬁle. M4 has a classic King-like proﬁle, whereas NGC 6397 has amore concentrated proﬁle, which is often interpreted as tha t of a post-core collapse cluster.Heggie & Giersz (2008), however, found that M4 is also a post-core collapse cluster, andGiersz & Heggie (2009) concluded that the main reason for the difference between the twosurface brightness proﬁles is ﬂuctuations. This conclusio n was reached on the basis of MonteCarlo models, however, and in the present Letter we verify that similar ﬂuctuations occur inN-body models. The models were initialised by generating initial conditions from the MonteCarlo model of NGC6397 at the simulated age of 12Gyr, and one was followed for 1Gyr.The new models help to clarify the nature of the ﬂuctuations, which have the nature of semi-regular oscillations with a time scale of order 10 8 yr. They are inﬂuenced by the dynamicalrole which is played by primordial binaries in the evolution of the core.Key words: stellar dynamics – methods: numerical – globular clusters: individual: NGC6397
Analyzing the Learning Process of an Online Role-Playing Discussion Activity

Instructional activities based on online discussion strategies have gained prevalence in recent years. Within this context, a crucial research topic is to design innovative and appropriate online discussion strategies that assist learners in attaining a deeper level of interaction and higher cognitive skills. By analyzing the process of online discussion in depth using a specific instructional strategy, we may discover the characteristics and limitations of this strategy. This case study utilizes an online discussion activity adopting a role-playing strategy in a college course and conducts an empirical analysis to explore and evaluate both the content structure and behavioral patterns in the discussion process. We propose and adopt a new method of multi-dimensional process analysis that integrates both content and sequential analysis, whereby the dimension of interaction and cognition are analyzed simultaneously. Furthermore, we discuss the patterns, characteristics, and limitations of the roleplaying discussions and provide suggestions as references for teachers who utilize online role-playing discussion activities.
Folk Theorems with Bounded Recall Under (Almost) Perfect Monitoring

A strategy profile in a repeated game has L bounded recall if play under the profile after two distinct histories that agree in the last L periods is equal. Mailath and Morris (2002, 2006) proved that any strict equilibrium in bounded-recall strategies of a game with full support public monitoring is robust to all perturbations of the monitoring structure towards private monitoring (the case of "almost-public monitoring"), while strict equilibria in unbounded-recall strategies are typically not robust. We prove that the perfect-monitoring folk theorem continues to hold when attention is restricted to strategies with bounded recall and the equilibrium is essentially required to be strict. The general result uses calendar time in an integral way in the construction of the strategy profile. If the players' action spaces are sufficiently rich, then the strategy profile can be chosen to be independent of calendar time. Either result can then be used to prove a folk theorem for repeated games with almost-perfect almost-public monitoring.
Losing the battle but winning the war: game theoretic analysis of the competition between motoneurons innervating a skeletal muscle

The fibers in a skeletal muscle are divided into groups called “muscle units” whereby each muscle unit is innervated by a single neuron. It was found that neurons with low activation thresholds have smaller muscle units than neurons with higher activation thresholds. This results in a fixed recruitment order of muscle units, from smallest to largest, called the “size principle. ” It is thought that the size principle results from a competitive process—taking place after birth—between the neurons innervating the muscle. The underlying mechanism of the competition was not understood. Moreover, the results in the majority of experiments that manipulated the activity during the competition period seemed to contradict the size principle. Experiments at the isolated muscle fibers showed that the competition is governed by a Hebbian-like rule, whereby neurons with low activation thresholds have a competitive advantage at any single muscle fiber. Thus neurons with low activation thresholds are expected to have larger muscle units in contradiction to what is seen empirically. This state of affairs was termed “paradoxical. ” In the present study we developed a new game theoretic framework to analyze such competitive biological processes. In this game, neurons are the players competing to innervate a maximal number of muscle fibers. We showed that in order to innervate more muscle fibers, it is advantageous to win (as the neurons with higher activation thresholds do) later competitions. This both explains the size principle and resolves the seemingly paradoxical experimental data. Our model establishes that the competition at each muscle fiber may indeed be Hebbian and that the size principle still emerges from these competitions as an overall property of the system. Thus, the less active neurons “lose the battle but win the war. ” Our model provides experimentally testable predictions. The new game-theoretic approach may be applied to competitions in other biological systems.
The Transcription Factor Zfp281 Controls Embryonic Stem Cell Pluripotency by Direct Activation and Repression of Target Genes

Oct4, Sox2, and Nanog are key components of a core transcriptional regulatory network that controls the ability of embryonic stem cells to differentiate into all cell types. Here we show that Zfp281, a zinc finger transcription factor, is a key component of the network and that it is required to maintain pluripotency. Zfp281 was shown to directly activate Nanog expression by binding to a site in the promoter in very close proximity to the Oct4 and Sox2 binding sites. We present data showing that Zfp281 physically interacts with Oct4, Sox2, and Nanog. Chromatin immunoprecipitation experiments identified 2,417 genes that are direct targets for regulation by Zfp281, including several transcription factors that are known regulators of pluripotency, such as Oct4, Sox2, and Nanog. Gene expression microarray analysis indicated that some Zfp281 target genes were activated, whereas others were repressed, upon knockdown of Zfp281. The identification of both activation and repression domains within Zfp281 suggests that this transcription factor plays bifunctional roles in regulating gene expression within the network.
Prevalence of cardiomyopathy in apparently healthy cats.

OBJECTIVE To determine the prevalence of cardiomyopathy and the relationship between cardiomyopathy and heart murmurs in apparently healthy cats. DESIGN Cross-sectional study. ANIMALS 103 privately owned, apparently healthy domestic cats. PROCEDURES Cats were physically and echocardiographically examined by 2 investigators independently. Left ventricular wall thickness was determined via 2-dimensional echocardiography in short-axis and long-axis planes. Left ventricular hypertrophy was identified when end-diastolic measurements of the interventricular septum or posterior wall were > or = 6 mm. Cats with left ventricular hypertrophy but without left ventricular dilatation were considered to have hypertrophic cardiomyopathy (HCM). The associations between heart murmurs and Doppler echocardiographic velocity profiles indicative of dynamic ventricular outflow tract obstruction were evaluated. RESULTS Heart murmurs were detected in 16 (15.5%; 95% confidence interval, 9.2% to 24.0%) cats; of these, 5 had cardiomyopathy. Cardiomyopathy was also identified in 16 (15.5%; 95% confidence interval, 9.2% to 24.0%) cats; 15 had HCM, and 1 had arrhythmogenic right ventricular cardiomyopathy. Of the cats with HCM, 11 had segmental left ventricular hypertrophy, 3 had diffuse left ventricular hypertrophy, and 1 had borderline left ventricular hypertrophy with marked systolic anterior motion of the mitral valve. Sensitivity and specificity of auscultatory detection of a heart murmur for diagnosing cardiomyopathy were 31% and 87%, respectively. Echocardiographic evidence of late systolic acceleration within ventricular outflow tracts was associated with the existence of a heart murmur. CONCLUSIONS AND CLINICAL RELEVANCE Cardiomyopathy was common in the healthy cats evaluated in this study. In apparently healthy cats, detection of a heart murmur is not a reliable indicator of cardiomyopathy.
Inside epoxyeicosatrienoic acids and cardiovascular disease

Epoxyeicosatrienoic acids (EETs) generated from arachidonic acid through cytochrome P450 (CYP) epoxygenases have many biological functions. Importantly, CYP epoxygenase-derived EETs are involved in the maintenance of cardiovascular homeostasis. In fact, in addition to their potent vasodilating effect, EETs have potent anti-inflammatory properties, inhibit platelet aggregation, promote fibrinolysis, and reduce vascular smooth muscle cell proliferation. All EETs are metabolized to the less active dihydroxyeicosatrienoic acids by soluble epoxide hydrolase (sEH). Numerous evidences support the role of altered EET biosynthesis in the pathophysiology of hypertension and suggest the utility of antihypertensive strategies that increase CYP-derived EET or EET analogs. Indeed, a number of studies have demonstrated that EET analogs and sEH inhibitors induce vasodilation, lower blood pressure and decrease inflammation. Some of these agents are currently under evaluation in clinical trials for treatment of hypertension and diabetes. However, the role of CYP epoxygenases and of the metabolites generated in cancer progression may limit the use of these drugs in humans.
Assessment of walker-assisted gait based on Principal Component Analysis and wireless inertial sensors

INTRODUCTION:This study investigates a gait research protocol to assess the impact of a walker model with forearm supports on the kinematic parameters of the lower limb during locomotion. METHODS: Thirteen healthy participants without any history of gait dysfunction were enrolled in the experimental procedure. Spatiotemporal and kinematic gait parameters were calculated by using wireless inertial sensors and analyzed with Principal Component Analysis (PCA). The PCA method was selected to achieve dimension reduction and evaluate the main effects in gait performance during walker-assisted gait. Additionally, the interaction among the variables included in each Principal Component (PCs) derived from PCA is exposed to expand the understanding of the main differences between walker-assisted and unassisted gait conditions. RESULTS:The results of the statistical analysis identified four PCs that retained 65% of the data variability. These components were associated with spatiotemporal information, knee joint, hip joint and ankle joint motion, respectively. CONCLUSION: Assisted gait by a walker model with forearm supports was characterized by slower gait, shorter steps, larger double support phase and lower body vertical acceleration when compared with normal, unassisted walking.
Studies on the Intestinal Absorption and Excretion of Calcium and Phosphorus in the Pig

In the preceding paper (Moore & Tyler, 1955) two main drawbacks were pointed out to the use of the Bergeim technique for investigating the intestinal absorption and excretion of calcium and phosphorus. Firstly, that it is impossible to determine by analysis of the gastro-intestinal contents the exact section of the tract where absorption of Ca and P is most rapid, mainly because of the lack of a satisfactory reference substance. Secondly, that there is no means of distinguishing between exogenous and endogenous Ca and P in the gastro-intestinal contents. I t seemed feasible that these two difficulties might be overcome to a certain extent by the use of radioactive isotopes of Ca and P. The absorption of Ca and P at a particular point along the tract from a feed containing 45Ca and 32P should be indicated by an increase in the specific activity of Ca and P in the wall of the gastro-intestinal tract. On the other hand, if the body tissues contain 45Ca and 32P and the gastro-intestinal tract is completely cleared of exogenous 45Ca and 32P it should be possible to determine the endogenous Ca and P in each section of the gastro-intestinal tract if the specific activity of the Ca and P in the blood is known.
Distance Based Revision of Preferential Logics

We first analyze AGM revision as conditions on choice functions for sets of models. This abstraction seems to us to capture the essentials of classical revision, it also immediately reveals the connection between revision and ranked preferential models, and gives further insight into the distance semantics for revision as developped by Lehmann, Magidor, and Schlechta. Our analysis shows how to apply the essential ideas of revision to other situations than classical theories and formulas, we exemplify this by examining preferential databases. We revise one preferential logic or database, ∼ | , with another one, ∼ | ′. The basic idea is to describe such a logic as a partial order, either as the order of a preferential model which defines the logic, or as the order between formulas defined by the logic. A partial order can be seen as the set of total orders which extend it, and, given a distance on the set of total orders, we can define a revision as follows: ∼ | ∗ ∼ | ′ will be the logic corresponding to the partial order generated by those total orders extending (the order of) ∼ | ′, which are closest to the set of total orders extending (the order of) ∼ | . We thus give a semantical approach to the problem. A representation result is proven.
Progesterone promotes neuronal differentiation of human umbilical cord mesenchymal stem cells in culture conditions that mimic the brain microenvironment

In this study, human umbilical cord mesenchymal stem cells from full-term neonates born by vaginal delivery were cultured in medium containing 150 mg/mL of brain tissue extracts from Sprague-Dawley rats (to mimic the brain microenvironment). Immunocytochemical analysis demonstrated that the cells differentiated into neuron-like cells. To evaluate the effects of progesterone as a neurosteroid on the neuronal differentiation of human umbilical cord mesenchymal stem cells, we cultured the cells in medium containing progesterone (0.1, 1, 10 μM) in addition to brain tissue extracts. Reverse transcription-PCR and flow cytometric analysis of neuron specific enolase-positive cells revealed that the percentages of these cells increased significantly following progesterone treatment, with the optimal progesterone concentration for neuron-like differentiation being 1 μM. These results suggest that progesterone can enhance the neuronal differentiation of human umbilical cord mesenchymal stem cells in culture medium containing brain tissue extracts to mimic the brain microenvironment.
Tailspike Interactions with Lipopolysaccharide Effect DNA Ejection from Phage P22 Particles in Vitro*

Initial attachment of bacteriophage P22 to the Salmonella host cell is known to be mediated by interactions between lipopolysaccharide (LPS) and the phage tailspike proteins (TSP), but the events that subsequently lead to DNA injection into the bacterium are unknown. We used the binding of a fluorescent dye and DNA accessibility to DNase and restriction enzymes to analyze DNA ejection from phage particles in vitro. Ejection was specifically triggered by aggregates of purified Salmonella LPS but not by LPS with different O-antigen structure, by lipid A, phospholipids, or soluble O-antigen polysaccharide. This suggests that P22 does not use a secondary receptor at the bacterial outer membrane surface. Using phage particles reconstituted with purified mutant TSP in vitro, we found that the endorhamnosidase activity of TSP degrading the O-antigen polysaccharide was required prior to DNA ejection in vitro and DNA replication in vivo. If, however, LPS was pre-digested with soluble TSP, it was no longer able to trigger DNA ejection, even though it still contained five O-antigen oligosaccharide repeats. Together with known data on the structure of LPS and phage P22, our results suggest a molecular model. In this model, tailspikes position the phage particles on the outer membrane surface for DNA ejection. They force gp26, the central needle and plug protein of the phage tail machine, through the core oligosaccharide layer and into the hydrophobic portion of the outer membrane, leading to refolding of the gp26 lazo-domain, release of the plug, and ejection of DNA and pilot proteins.