Miracle-dz/UniFAR-FTUs huggingface dataset:
Stochastic learning in oxide binary synaptic device for neuromorphic computing

Hardware implementation of neuromorphic computing is attractive as a computing paradigm beyond the conventional digital computing. In this work, we show that the SET (off-to-on) transition of metal oxide resistive switching memory becomes probabilistic under a weak programming condition. The switching variability of the binary synaptic device implements a stochastic learning rule. Such stochastic SET transition was statistically measured and modeled for a simulation of a winner-take-all network for competitive learning. The simulation illustrates that with such stochastic learning, the orientation classification function of input patterns can be effectively realized. The system performance metrics were compared between the conventional approach using the analog synapse and the approach in this work that employs the binary synapse utilizing the stochastic learning. The feasibility of using binary synapse in the neurormorphic computing may relax the constraints to engineer continuous multilevel intermediate states and widens the material choice for the synaptic device design.
Merging maps of multiple robots

Merging local maps, acquired by multiple robots, into a global map, (also known as map merging) is one of the important issues faced by virtually all cooperative exploration techniques. We present a novel and simple solution to the problem of map merging by reducing it to the problem of SLAM of a single ¿virtual¿ robot. The individual local maps and their shape information constitute the sensor information for the virtual robot. This approach allows us to adapt the framework of Rao-Blackwellized particle filtering used in SLAM of a single robot for the problem of map merging.
The serpin PN1 is a feedback regulator of FGF signaling in germ layer and primary axis formation

Germ layer formation and primary axis development rely on Fibroblast growth factors (FGFs). In Xenopus, the secreted serine protease HtrA1 induces mesoderm and posterior trunk/tail structures by facilitating the spread of FGF signals. Here, we show that the serpin Protease nexin-1 (PN1) is transcriptionally activated by FGF signals, suppresses mesoderm and promotes head development in mRNA-injected embryos. An antisense morpholino oligonucleotide against PN1 has the opposite effect and inhibits ectodermal fate. However, ectoderm and anterior head structures can be restored in PN1-depleted embryos when HtrA1 and FGF receptor activities are diminished, indicating that FGF signals negatively regulate their formation. We show that PN1 binds to and inhibits HtrA1, prevents degradation of the proteoglycan Syndecan 4 and restricts paracrine FGF/Erk signaling. Our data suggest that PN1 is a negative-feedback regulator of FGF signaling and has important roles in ectoderm and head development. Summary: The serpin PN1, which is transcriptionally activated by FGF signals, inhibits the protease HtrA1 and prevents syndecan-4 degradation to restrict FGF signaling during Xenopus head development.
Small-Molecule Antagonists for CXCR2 and CXCR1 Inhibit Human Melanoma Growth by Decreasing Tumor Cell Proliferation, Survival, and Angiogenesis

Purpose: Melanoma, the most aggressive form of skin cancer, accounts for 75% of all skin cancer-related deaths and current therapeutic strategies are not effective in advanced disease. In the current study, we have investigated the efficacy of orally active small-molecule antagonist targeting CXCR2/CXCR1. Experimental Design: Human A375SM melanoma cells were treated with SCH-479833 or SCH-527123, and their effect on proliferation, motility, and invasion was evaluated in vitro. We examined the downstream signaling events in the cells following treatment with antagonists. For in vivo studies, A375SM cells were implanted subcutaneously into athymic nude mice followed by administration of SCH-479833, SCH-527123, or hydroxypropyl-β-cyclodextrin (20%) orally for 21 days and their effect on tumor growth and angiogenesis was evaluated. Results: Our data show that SCH-479833 or SCH-527123 inhibited the melanoma cell proliferation, chemotaxis, and invasive potential in vitro. Treatment of melanoma cells with SCH-479833 or SCH-527123 also inhibited tumor growth. Histologic and histochemical analyses showed significant (P < 0.05) decreases in tumor cell proliferation and microvessel density in tumors. Moreover, we observed a significant increase in melanoma cell apoptosis in SCH-479833- or SCH-527123-treated animals compared with controls. Conclusion: Together, these studies show that selectively targeting CXCR2/CXCR1 with orally active small-molecule inhibitors is a promising therapeutic approach for inhibiting melanoma growth and angiogenesis.
Twice-hyphenated: transnational identity among second-generation Ethiopian-American professionals in the Washington, DC, metropolitan area

ABSTRACT This article examines the dynamics of transnational identity among second-generation Ethiopian-American professionals. Drawing on the experiences of 21 second-generation Ethiopian-American professionals, I analyze how they manage the dual challenges of maintaining Ethiopian identities while embracing American values and aspirations. Study participants indicated how their parents actively encourage them to embrace Ethiopian culture while they expect them to succeed in the US society. They expressed fear that if they become ‘too American’, they will disappoint their parents. Moreover, they find restricting their identity to one group or another too confining. They selectively choose defining ethnic characteristics from the cultural domains in which they operate –their families, social networks, and school environments; media images; popular culture; and the broader dominant culture. Most of them embrace individualism and autonomy in order to negotiate, create, and recreate their own transnational identities. The ethnic characteristics of second-generation Ethiopian-American can certainly be characterized as ‘hybrid identities’.
Measurement and analysis of topology and information propagation on Sina-Microblog

Sina-Microblog, the earliest and biggest microblogging service in China, has become one of the most popular media in information propagation. In order to gain insights into the topological and information diffusing characteristics of microblogging network in China, we crawled Sina-Microblog for about 3 months and obtain the trace of its topology and topics. Compared with other online social networks, our measurement study shows a number of interesting findings. Our data suggests that Sina-Microblog network has apparent small-world effect and scale-free characteristic, specially, the outdegree distribution appears to have multiple separate power-law regimes with different exponents. We also observe the overlay graph of Sina-Microblog represents assortative mixing pattern and weak correlation of indegree and outdegree. Moreover, by constructing the cascades of different topics, our data suggests that the distribution of cascades size follows a power-law and heavy-tailed property with the slope approximately −2, and the common motifs of cascades with different topics are very similar, above 93% of them are isolated nodes. In order to find the formative motivity of hot cascades, we find that they always evolve to the structures like ‘star pattern’ and ‘two-polar pattern’, which are mainly due to the indegree of participating nodes, and are also correlated with the content of tweet.
A SIMPLE AND RAPID METHOD FOR THE ISOLATION OF ENZYMATICALLY ACTIVE HELA CELL NUCLEI

Since HeLa cells are one of the most commonly studied established cell lines, there is a need for a simple and rapid method for isolating enzymatically active cell nuclei which are not aggregated and thus can be pipetted in reproducible aliquots . We report here such a procedure which may be used for both large and small volumes of suspension cultures and which requires no specialized equipment. The method is a modification of previous techniques (1-3), all of which are based upon the use of Triton detergents . Although several other procedures for isolating HeLa cell nuclei have been published (4-7), the convenience and utility of the present method warrant consideration .
Combating Deep Reinforcement Learning ’ s Sisyphean Curse with Reinforcement Learning

To use deep reinforcement learning in the wild, we might hope for an agent that can avoid catastrophic mistakes. Unfortunately, even in simple environments, the popular deep Q-network (DQN) algorithm is doomed by a Sisyphean curse. Owing to the use of function approximation, these agents may eventually forget experiences as they become exceedingly unlikely under a new policy. Consequently, for as long as they continue to train, DQNs may periodically repeat avoidable catastrophic mistakes. In this paper, we learn a reward shaping that accelerates learning and guards oscillating policies against repeated catastrophes. First, we demonstrate unacceptable performance of DQNs on two toy problems. We then introduce intrinsic fear, a new method that mitigates these problems by avoiding dangerous states. Our approach incorporates a second model trained via supervised learning to predict the probability of catastrophe within a short number of steps. This score then acts to penalize the Q-learning objective. Equipped with intrinsic fear, our DQNs solve the toy environments and improve on the Atari games Seaquest, Asteroids, and Freeway.
A Review of 3D Reconstruction of Coronary Arteries Based on the Co-registration of IVUS and Coronary Angiogram

This paper presents a review of 3D reconstruction of coronary arteries based on the co-registration of Intravascular Ultrasound (IVUS) and coronary angiogram. This method has been proposed to ease the process of diagnosis and treatment for coronary artery disease, which is highlighted as a global disease. The purpose of this paper is to provide an introduction and understanding of the works that have been done. This paper consists of an introduction, importance of 3D coronary artery, registration process, background of IVUS and coronary angiogram, and a brief description about previous works.
Link Performance Model for Multihop WiMax OFDMA Systems

A two-phased approach is proposed to estimate the overall multi-hop WiMax system performance. The proposed methodology is generic and can embrace various multi transmit multi receive techniques along with different possible (H)ARQ mechanisms. Advanced modulation and coding sub-carrier mapping is assumed for static and low mobility links to allow operation of adaptive techniques such as dynamic band allocation and beam-forming. PUSC sub-carrier mapping is assumed to be used for dynamic and high mobility links. In order to illustrate our methodology, the overall PER performance of a two-hop system with eigen beam- forming in first hop and either Alamouti or Golden codes in the second hop has been estimated. The results are based on the combination of the two link performance models, i.e., actual value interface for the first hop and average value interface for the second hop.
Structural micro forces in online social networking websites: Impact on friendship structure

There is already a modest body of research on structural properties of online social networking websites. However, there seems to be a big gap when it comes to important questions related to underlying network forces that create that structure. Drawing from empirically grounded theories of off-line communication networks, hypotheses about the biases (forces) creating the friendship structure in educational online social networking websites are set up, for dyadic and triadic levels of analysis. Hypothesized micro forces are then empirically investigated by building probabilistic models from the data of an online educational social network, using recent reformulations of a biased net modeling approach. In addition, magnitudes of forces are investigated longitudinally, based on five observations of a network. Results indicate the existence of all the hypothesized micro structural forces. Reciprocity is by far the strongest force acting in the network, followed by transitivity, similarity and lastly, closure. Reciprocity is shown to increase with the time, whereas transitivity and similarity decrease. Closure bias first decreases, and then steadily increases.
DATA MINING IN RADIATION PORTAL MONITORING

Currently deployed passive gamma and neutron detectors screen for illicit nuclear material. Archived data can help evaluate special nuclear material detection probabilities and investigate several related issues, including (1) nuisance gamma alarms arising from naturally occurring radiation, (2) the impact of drifting neutron and gamma background rates, and (3) radioisotope identification performance. This paper illustrates roles for data mining to investigate issue (1) and briefly reviews data mining to investigate issues (2) and (3).
Multi-depth valved microfluidics for biofilm segmentation

Bacterial biofilms present a societal challenge, as they occur in the majority of infections but are highly resistant to both immune mechanisms and traditional antibiotics. In the pursuit of better understanding biofilm biology for developing new treatments, there is a need for streamlined, controlled platforms for biofilm growth and evaluation. We leverage advantages of microfluidics to develop a system in which biofilms are formed and sectioned, allowing parallel assays on multiple sections of one biofilm. A microfluidic testbed with multiple depth profiles was developed to accommodate biofilm growth and sectioning by hydraulically actuated valves. In realization of the platform, a novel fabrication technique was developed for creating multi-depth microfluidic molds using sequentially patterned photoresist separated and passivated by conformal coatings using atomic layer deposition. Biofilm thickness variation within three separately tested devices was less than 13% of the average thickness in each device, while variation between devices was 23% of the average thickness. In a demonstration of parallel experiments performed on one biofilm within one device, integrated valves were used to trisect the uniform biofilms with one section maintained as a control, and two sections exposed to different concentrations of sodium dodecyl sulfate. The technology presented here for multi-depth microchannel fabrication can be used to create a host of microfluidic devices with diverse architectures. While this work focuses on one application of such a device in biofilm sectioning for parallel experimentation, the tailored architectures enabled by the fabrication technology can be used to create devices that provide new biological information.
Getting the most of WiFi mesh networks with 802.16 mesh emulation

Currently deployed wireless mesh networks are based on 802.11, WiFi technology, which is not efficient in multihop scenarios. We present a method, which emulates 802.16 mesh networks over 802.11 hardware. The method works by embedding 802.16 packets into 802.11 broadcast packets and padding the 802.11 broadcast payload, so that the broadcasts are aligned to 802.16 time division multiple access frame boundaries. The method requires only software changes on the nodes using 802.11a for mesh communications. This means that the mesh networks installed with 802.11a hardware today can be upgraded with a software patch to take advantage of quality-of-service available in 802.16. We use ns2 simulations to show the performance of the 802.11 based mesh networks with the embedded 802.16. We show that the hybrid system can achieve throughputs in multiples of what is possible with 802.11 hardware alone. First, the efficiency of the new system is significantly higher than the efficiency of 802.11 based systems, because we use broadcast packets. Second, the new system eliminates unnecessary collisions in the wireless channel since it takes advantage of scheduled wireless access with 802.16 mesh coordination function.
An Improved MNF Transform Algorithm on Hyperspectral Images with Complex Mixing Ground Objects

Transforms on the spectral domain are often used to compress and extract information of sample features for the supervised classification on hyperspectral images. On condition that the ground samples are all in mass each, there are more obvious advantages on sample classification with obscure spectral features when using Maximum Noise Fraction (MNF) transform, or named two cascaded principal components analysis method, compared with Principle Components (PC) image transform. But through the experiments in this article below, it is proved that the classification accuracy will decrease obviously using MNF method when the samples of different ground object classes are complexly mixed. Then the article illustrates the rules and reasons for these influences. Aiming at this problem of the low classification accuracy when the ground samples are too scattered, an improve method of estimating image Noise Covariance Matrix (CM) of hyperspectral images is introduced to enhance the feature extraction effect of the MNF method. The followed experiment shows that the classification accuracy is increased effectively when using it compare with classic MNF method.
Single-walled carbon nanotube electronics

Single-walled carbon nanotubes (SWNTs) have emerged as a very promising new class of electronic materials. The fabrication and electronic properties of devices based on individual SWNTs are reviewed. Both metallic and semiconducting SWNTs are found to possess electrical characteristics that compare favorably to the best electronic materials available. Manufacturability issues, however, remain a major challenge.
Ethical leadership and employee task performance: examining moderated mediation process

The purpose of this paper is to examine the impact of ethical leadership on employee task performance, specifically the mechanisms through which ethical leadership impacts employee task performance and the moderating role of employee proactive personality. Social identity, social learning, and self-concordance theory were used to explain the way ethical leadership affects employee task performance, and provided another way to understand this relationship. ,The authors collected survey-based dyadic data from middle management team members and subordinates in Chinese companies. Multiple regression analysis was used to test the research hypotheses. ,The empirical findings indicate that ethical leadership positively influences employee task performance. Organizational identification (OID) mediates the relationship between ethical leadership and employee task performance. Furthermore, the relationship between ethical leadership and employee task performance via OID is moderated by employee proactive personality. ,Employee task performance is critical for a firm’s competitive advantage. This paper adds to knowledge about the relationship between ethical leadership and employee task performance and contributes to effective management.
A Feasible Nonconvex Relaxation Approach to Feature Selection

Variable selection problems are typically addressed under apenalized optimization framework. Nonconvex penalties such as the minimax concave plus (MCP) and smoothly clipped absolute deviation(SCAD), have been demonstrated to have the properties of sparsity practically and theoretically. In this paper we propose a new nonconvex penalty that we call exponential-type penalty. The exponential-type penalty is characterized by a positive parameter,which establishes a connection with the ell0 and ell1 penalties.We apply this new penalty to sparse supervised learning problems. To solve to resulting optimization problem, we resort to a reweighted ell1 minimization method. Moreover, we devise an efficient method for the adaptive update of the tuning parameter. Our experimental results are encouraging. They show that the exponential-type penalty is competitive with MCP and SCAD.
Homotopy continuation method for solving hyperbolic form of Kepler's equation

Abstract. In this paper, error formulae for solving a hyperbolic form of Ke-pler’s equation using the homotopy continuation method will be establishedfor an arbitrary order of convergence m ≥ 2.Key words: Homotopy –Kepler’s equation – celestial mechanics 1. Introduction Many instances of hyperbolic orbits occur in the solar system and , recently,amongthe artiﬁcialsatellites, lunar and solarproblems.Moreover,in some casesof the orbit determination for an elliptic orbit it may very well happen (Escobal,1975) that during the solution process (usually iteration), the eccentricity be-comes greater than unity and the orbit becomes hyperbolic. In addition, ininterplanetary transfer, the escape from the departure planet and the captureby the target planet involves hyperbolic orbits (Gurzadyan, 1996). On the otherhand, in the orbit determination of visual binaries provisional hyperbolic orbitsare used to represent the perienteron section of high - eccentricity orbits of along and indeterminate period (Knudsen, 1953). In fact, we should handle hy-perbolic orbits frequently when integrating a perturbed motion with the initialcondition of nearly parabolic orbits (Fukushima, 1997). From the above it is then clear that the hyperbolic orbits not only existnaturally, but can also be used to solve some critical orbital situations. Theposition - time relation in hyperbolic orbits is known as Kepler’s equation forthe hyperbolic case and is given as
Fast Ordering for Changing XML Data

With the increasing popularity of XML, there arises the need for managing and querying information in this form. Several query languages, such as XQuery, have been proposed which return their results in document order. However, most recent efforts focused on query optimization have either disregarded order or proposed a static labelling scheme in which update issues are not addressed. Based on the preliminary results from our previous work, this paper presents a fast method to maintain document ordering for changing XML data. Analysis of our method shows that it is more efﬁcient and scalable than our previously proposed method as well as other related work, especially under various scenarios of updates.
Sleeping with a broken promise: The moderating role of generativity concerns in the relationship between psychological contract breach and insomnia among older workers

Summary This paper examines the relationship between psychological contract breach and insomnia among older workers (aged 40 years and up). Drawing upon the conservation of resources theory, we conceptualize breach as a stressful event characterized by a perceived threat, failure to gain, or actual loss of valued resources, which increases psychological distress and insomnia. Moreover, we hypothesized that older workers' generativity concerns would act as a personal resource that would buffer the negative impact of breach. We tested our proposed model in 2 studies (Study 1 = 123; Study 2 = 168) of employee–spouse dyads. Results revealed that psychological distress mediated the relationship between psychological contract breach and insomnia. These mediated relationships were significant for those with low, but not for those with high levels of generativity concerns. These effects remained significant even after controlling for perceived organizational support (i.e., a social exchange mechanism). Theoretical and practical implications are discussed.