Miracle-dz/UniFAR-FTUs huggingface dataset:
Algorithms for Distance Problems in Planar complexes of Global nonpositive Curvature

CAT(0) metric spaces and hyperbolic spaces play an important role in combinatorial and geometric group theory. In this paper, we present efficient algorithms for distance problems in CAT(0) planar complexes. First of all, we present an algorithm for answering single-point distance queries in a CAT(0) planar complex. Namely, we show that for a CAT(0) planar complex with n vertices, one can construct in O(n2log n) time a data structure of size O(n2) so that, given a point , the shortest path γ(x, y) between x and the query point y can be computed in linear time. Our second algorithm computes the convex hull of a finite set of points in a CAT(0) planar complex. This algorithm is based on Toussaint's algorithm for computing the convex hull of a finite set of points in a simple polygon and it constructs the convex hull of a set of k points in O(n2log n + nk log k) time, using a data structure of size O(n2 + k).
Protective effect of thioredoxins 1 and 2 in retinal ganglion cells after optic nerve transection and oxidative stress.

PURPOSE Oxidative stress has been implicated in retinal ganglion cell (RGC) death pathways after optic nerve transection (ONT) and during glaucomatous neuropathy. The authors investigated the expression and cell-protective roles of thioredoxins (cytosolic Trx1 and mitochondrial Trx2), important regulators of the cellular redox state, on RGCs after ONT and pharmacologic oxidative stress induction. METHODS ONT was performed on adult Wistar rats. Trx1 and Trx2 quantitative and spatial expression were examined with Western blot and immunohistochemistry, respectively. Electroporation and calcium phosphate-mediated procedures were used to deliver Trx1 and Trx2 expression constructs to RGCs in vivo and to cultured RGC-5 cells, respectively. Cell-protective effects of Trx1 and Trx2 overexpression on RGCs after ONT and on RGC-5 cells treated with glutamate/buthionine sulfoximine (BSO) were determined by RGC density analysis and cell viability assay, respectively. RESULTS Upregulation of Trx1 and Trx2 was observed in RGCs at different times after ONT and in RGC-5 cells after glutamate/BSO treatment. Trx1 and Trx2 overexpression in RGC-5 cells increased their survival rate by approximately twofold and threefold 24 and 48 hours after glutamate/BSO treatment, respectively. A neuroprotective effect of Trx1 and Trx2 overexpression on RGCs was also observed in vivo; the survival rate of RGCs was increased by 35% and 135%, respectively, 1 and 2 weeks after ONT. CONCLUSIONS These findings provide evidence for in vitro and in vivo cell-protective effects of Trx1 and Trx2 on RGCs against oxidative stress-induced neurodegeneration.
TSTMT: step towards an accurate Thai sign translation

We propose Thai sign to Thai machine translation (TSTMT), an alternative approach to machine translation which is used for translating from Thai sign language into Thai text. TSTMT performs the translation by recognizing an image sequence of signs as sign words and synthesizing a target sentence from those sign words. TSTMT represents a hybrid of image recognition and natural language processing techniques. This approach is comprised of seven modules which are straightforward and extendable. The applications of TSTMT can be used to facilitate learning in deaf people and to help them to communicate with hearing people via their own language. In this paper the idea and initial experiment are presented.
Arbitrating Traffic Contention for Power Saving with Multiple PSM Clients

Data transmission over WiFi quickly drains the batteries of mobile devices. Although the IEEE 802.11 standards provide power save mode (PSM) to help mobile devices conserve energy, PSM fails to bring expected benefits in many real scenarios. In particular, when multiple PSM mobile devices associate to a single access point (AP), PSM does not work well under transmission contention. Optimizing power saving of multiple PSM clients is a challenging task, because each PSM client expects to complete data transmission early so that it can turn to low power mode. In this paper, we define an energy conserving model to describe the general PSM traffic contention problem. We prove that the optimization of energy saving for multiple PSM clients under constraint is an NPcomplete problem. Following this direction, we propose a solution called harmonious power saving mechanism (HPSM) to address one specific case, in which multiple PSM clients associate to a single AP. In HPSM, we first use a basic sociological concept to define the richness of a PSM client based on the link resource it consumes. Then, we separate these poor PSM clients from rich PSM clients in terms of link resource consumption and favor the former to save power when they face PSM transmission contention. We implement prototypes of HPSM based on the open source projects Mad-wifi and NS-2. Our evaluations show that HPSM can help the poor PSM clients effectively save power while only slightly degrading the rich PSM clients' performance in comparison with the existing PSM solutions.
Lognormal moment matching and pricing of basket options

In this paper we will approximate the sum of the margins from a two dimensional lognormal variable by moment matching with a one dimensional lognormal variable. We will look at different cases of correlation and volatility in the two dimensional variable to analyse the accuracy of the approximation. Basket options will be valuated based on the sum of two coupled lognormal assets and a univariate approximation to detect situations where the moment matching may be successfully applied in a financial market.
How Users Bypass Access Control - And Why: The Impact Of Authorization Problems On Individuals And The Organization

Many organizations struggle with ineffective and/or inefficient access control, but these problems and their consequences often remain invisible to security decision-makers. Prior research has focused on improving the policy-authoring part of authorization and does not consider the full range of underlying problems, and their impact on organizations. We present a study of 118 individuals’ experiences of authorization measures in a multi-national company, and their self-reported subsequent behavior. Building on recent research that applies economic models to show the impact of lack of usability, we analyze the interrelations of authorization issues with individuals’ behaviors and organizational goals. Our results indicate that authorization problems significantly reduce the productivity and effective security of organizations. We analyzed the authorization problems of different stakeholders, and found they are mostly caused by the procedures for policy changes (e.g. long change lead-times) and the decision-making (e.g. inexperienced decision makers); the consequence is the circumvention of access control (e.g. by sharing passwords). As one research contribution, we develop a holistic model of authorization problems. More practically, we recommend to provide guidance for non-compliance, such as password-sharing, and to establish light-weight procedures for policy changes with adequate degrees of centralization and formalization, and support for decision-making.
Regulation of Synaptic Strength and AMPA Receptor Subunit Composition by PICK1

PICK1 (protein interacting with C kinase-1) regulates the surface expression of the AMPA receptor (AMPAR) GluR2 subunit, however, the functional consequences of this interaction are not well understood. Previous work has suggested that PICK1 promotes the internalization of AMPARs. However, we found that when PICK1 is virally expressed in the CA1 region of hippocampal slices, it causes an increase in AMPAR-mediated EPSC amplitude. This effect is associated with increased AMPAR rectification and sensitivity to polyamine toxin. These effects are blocked by PKC or calcium/calmodulin-dependent protein kinase II inhibitors, indicating that the virally expressed PICK1 signals through an endogenous kinase cascade. In contrast, blockade of interactions with GluR2 at the N-ethylmaleimide-sensitive factor site did not cause a change in subunit composition, suggesting that the effects of PICK1 are not simply a nonspecific consequence of removing AMPARs from the surface. Immunocytochemical and biochemical analyses in dissociated cultured hippocampal neurons show that PICK1 causes a decrease in endogenous GluR2 surface expression but no change in GluR1 surface levels. To address the physiological role of PICK1, we virally expressed C-terminal GluR2 peptides. Blockade of endogenous PICK1 PDZ (postsynaptic density-95/Discs large/zona occludens-1) domain interactions produced opposite effects on synaptic strength and AMPAR rectification to those observed with PICK1 expression. This demonstrates that AMPAR subunit composition is physiologically regulated through a mechanism involving PICK1 PDZ domain interactions. These findings suggest that PICK1 acts to downregulate the GluR2 content of AMPARs at hippocampal CA1 synapses, thereby increasing synaptic strength at resting membrane potentials.
A FIRST LOOK AT GALAXY FLYBY INTERACTIONS. I. CHARACTERIZING THE FREQUENCY OF FLYBYS IN A COSMOLOGICAL CONTEXT

Hierarchical structure formation theory is based on the notion that mergers drive galaxy evolution, so a considerable framework of semi-analytic models and N-body simulations has been constructed to calculate how mergers transform a growing galaxy. However, galaxy mergers are only one type of major dynamical interaction between halos—another class of encounter, a close flyby, has been largely ignored. We use cosmological N-body simulations to reconstruct the entire dynamical interaction history of dark matter halos. We present a careful method of identifying and tracking a dark matter halo which resolves the typical classes of anomalies that occur in N-body data. This technique allows us to robustly follow halos and several hierarchical levels of subhalos as they grow, dissolve, merge, and flyby one another—thereby constructing both a census of the dynamical interactions in a volume and an archive of the dynamical evolution of an individual halo. In addition to a census of mergers, our tool characterizes the frequency of close flyby interactions in the universe. We find that the number of close flyby interactions is comparable to, or even surpasses, the number of mergers for halo masses ≳ 1011 M☉ h−1 at z ≲ 2. Halo flybys occur so frequently to high-mass halos that they are continually perturbed, unable to reach a dynamical equilibrium. In particular, we find that Milky Way type halos undergo a similar number of flybys as mergers irrespective of mass ratio for z ≲ 2. We also find tentative evidence that at high redshift, z ≳ 14, flybys are as frequent as mergers. Our results suggest that close halo flybys can play an important role in the evolution of the earliest dark matter halos and their galaxies, and can still influence galaxy evolution at the present epoch. Our companion paper quantifies the effect of close flyby interactions on galaxies and their dark matter hosts.
Spending on Daughters Versus Sons in Economic Recessions

Although parents often try not to favor one child, we examine whether specific environmental factors might bias parents to favor children of one sex over the other. This research draws on theory in evolutionary biology suggesting that investment in female versus male offspring depends on resource availability. Applying this to consumers, a series of experiments show that poor economic conditions favor resource allocations to daughters over sons. For example, poor conditions led people to bequeath more assets to girls in their will, and to choose girls to receive a US Treasury bond and a beneficial extracurricular activity. It is proposed that this happens because spending on children represents a reproductive investment, and that boys’ and girls’ relative reproductive value varies with economic conditions. Supporting this account, perceptions of which child will have more children statistically mediates the effect of economic conditions on preferences for girls. Consequently, the effect is strengthened as a child approaches reproductive age, and it is moderated by individual differences (risk aversion and monogamy) directly related to our theoretical model. This research contributes to the consumer behavior literature by revealing how, why, and when environmental factors influence spending on girls versus boys.
Interaction between SGT1 and Cytosolic/Nuclear HSC70 Chaperones Regulates Arabidopsis Immune Responses[W]

The conserved eukaryotic protein SGT1 (for Suppressor of G2 allele of skp1) has characteristics of an HSP90 (for heat shock protein 90 kD) cochaperone and in plants regulates hormone responses and Resistance gene–triggered immunity. We affinity-purified SGT1-interacting proteins from Arabidopsis thaliana leaf extracts and identified by mass spectrometry cytosolic heat shock cognate 70 (HSC70) chaperones as the major stable SGT1 interactors. Arabidopsis SGT1a and SGT1b proteins associate with HSC70 in vivo and distribute with HSC70 in the cytosol and nucleus. An intact C-terminal SGT1-specific (SGS) domain that is required for all known SGT1b functions in immunity and development is needed for HSC70 interaction and for the nuclear accumulation of SGT1b. Interaction assays of transiently expressed proteins or their domains in Nicotiana benthamiana point to a role of SGT1 as a HSC70 cofactor. Expression of two HSC70 isoforms is upregulated by pathogen challenge, and while loss of function of individual cytosolic HSC70 genes has no defense phenotype, HSC70-1 overexpression disables resistance to virulent and avirulent pathogens. Moreover, mutations in SGT1b lead to a similar degree of heat shock tolerance as deregulation of HSC70-1. We conclude that an HSC70-SGT1 chaperone complex is important for multiple plant environmental responses and that the evolutionarily conserved SGS domain of SGT1 is a key determinant of the HSC70–SGT1 association.
An Overdensity of i-Dropouts among a Population of Excess Field Objects in the Virgo Cluster

Using a set of deep imaging data obtained by the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope (HST) shortly after its deployment, Yan, Windhorst, & Cohen found a large number of F775W-band dropouts (i-dropouts), which are consistent with being galaxies at z ≈ 6. The surface density of i-dropouts thus derived, however, is an order of magnitude higher than those subsequent studies found in other deep ACS fields, including the Hubble Ultra Deep Field (HUDF). Here we revisit this problem, using both existing and new data. We confirm that the large overdensity of i-dropouts does exist in this field, and that their optical-to-IR colors are similar to those in the HUDF. However, we have discovered that the i-dropout overdensity is accompanied by an even larger excess of faint field objects in this region and its vicinity. This large excess of field objects is most likely caused by the fact that we have resolved the faint diffuse light extending from an interacting galaxy pair in the Virgo Cluster, M60/NGC 4647, which lies several arcminutes away from the region where the excess is found. The i-dropouts in this field are within the magnitude range where this excess of field objects occurs, and their spatial distribution seems to follow the same gradient as the entire excess field population. This excess population is also red in color, and the red wing of its color distribution continuously extends to the regime where the i-dropouts reside. While we still cannot completely rule out the possibility that the overdensity of i-dropouts might be a genuine large-scale structure of galaxies at z ≈ 6, we prefer the interpretation that most of them are part of the excess stellar population related to M60/NGC 4647.
Multi-swarm Optimization with Chaotic Mapping for Dynamic Optimization Problems

In real-world applications, many optimization problems are dynamic, therefore the goal of optimization algorithms is not only to obtain the optimal solution, but also to have strong adaptive capability to the environment changes and track the trajectory of the optimal solution as closely as possible. In this paper, a new multi-swarm optimization algorithm with chaotic mapping strategy based on particle swarm optimization (PSO) is proposed. The proposed algorithm adopts an improved multi-swarm approach and employs PSO as global and local search method. A modified chaotic mapping mechanism is presented to overcome the challenge of diversity loss. The Moving Peaks Benchmark is utilized to evaluate the performance of the proposed algorithm and experimental results have been compared with other algorithms. The results show that the proposed algorithm has good performance and outperforms others on most of the test cases.
The Length of Bridge Ties: Structural and Geographic Properties of Online Social Interactions

The popularity of the Web has allowed individuals to communicate and interact with each other on a global scale: people connect both to close friends and acquaintances, creating ties that can bridge otherwise separated groups of people. Recent evidence suggests that spatial distance is still affecting social links established on online platforms, with online ties preferentially connecting closer people. In this work we study the relationships between interaction strength, spatial distance and structural position of ties between members of a large-scale online social networking platform, Tuenti. We discover that ties in highly connected social groups tend to span shorter distances than connections bridging together otherwise separated portions of the network. We also find that such bridging connections have lower social interaction levels than ties within the inner core of the network and ties connecting to its periphery. Our results suggest that spatial constraints on online social networks are intimately connected to structural network properties, with important consequences for information diffusion.
A tilt after-effect for images of buildings: evidence of selectivity for the orientation of everyday scenes

The tilt after-effect (TAE) is thought to be a manifestation of gain control in mechanisms selective for spatial orientation in visual stimuli. It has been demonstrated with luminance-defined stripes, contrast-defined stripes, orientation-defined stripes and even with natural images. Of course, all images can be decomposed into a sum of stripes, so it should not be surprising to find a TAE when adapting and test images contain stripes that differ by 15° or so. We show this latter condition is not necessary for the TAE with natural images: adaptation to slightly tilted and vertically filtered houses produced a ‘repulsive’ bias in the perceived orientation of horizontally filtered houses. These results suggest gain control in mechanisms selective for spatial orientation in natural images.
An ontological account of donald schön's reflection in designing

This paper proposes an ontological model of Donald Schon’s notion of reflection in the domain of designing. We address two views of this notion. First, we present a functional view that describes reflection in terms of the designer’s interactions with the design object and their intended and unintended consequences that then drive further interactions. Second, we present a constructional view that models reflection as a mechanism with a set of properties that distinguish it from other processes in designing. We describe both views using the function-behaviour-structure (FBS) ontology. This elaborates existing accounts of reflection and locates it within a uniform framework of designing, which lays the foundations for a multi-disciplinary approach to studying reflection.
Single Machine Scheduling with Common Due Date Based on PSO Integrated with Heuristics

The classical particle swarm optimization (PSO) is a powerful method to find the minimum of for a function optimization problem, especially with a continuous solution space. So far, it has not been widely applied to solving those problems with discrete features. We attempt to deal with the problem of scheduling jobs on a single machine against common due dates with respect to earliness and tardiness penalties in this paper. A PSO strategy integrated with a kind of heuristic algorithm is proposed, where the heuristic information is composed of the processing time and tardiness penalty for each job. It is indicated that such strategy can significantly improve the performance of the solutions. Furthermore, we demonstrate by numerical benchmark examples from OR-Library that our algorithm is both effective and efficient in achieving satisfied solutions for scheduling problems with earliness and tardiness penalties
Enhancing statistical semantic networks with concept hierarchies

With the emergence of the semantic web, effective knowledge representation has gained importance. Statistically generated semantic networks are simple representations whose semantic power is yet to be completely explored. Though, these semantic networks are created with simple statistical measures without much overhead, they have the potential to express the semantic relationship between concepts. In this paper, we explore the capability of such networks and enhance them with concept hierarchies to serve as better knowledge representations. The concept hierarchies are built based on the level of importance of concepts. The level of importance/coverage of a concept within the given set of documents has to be taken into account to build an effective knowledge representation. In this paper, we provide a domain-independent, graph based approach for identifying the level of importance of each concept from the statistically generated semantic network which represents the entire document set. Insights about the depth of every concept is obtained by analysing the graph theoretical properties of the statistically generated semantic network. A generic concept hierarchy is created using a greedy strategy, and the original semantic network is reinforced with this concept hierarchy. Experiments over different data sets demonstrate that our approach works effectively in classifying concepts and generating taxonomies based on it, thereby effectively enhancing the semantic network.