Miracle-dz/UniFAR-FTUs huggingface dataset:
Lower-limb muscular strategies for increasing running speed.

SYNOPSIS This clinical commentary discusses the mechanisms used by the lower-limb musculature to achieve faster running speeds. A variety of methodological approaches have been taken to evaluate lower-limb muscle function during running, including direct recordings of muscle electromyographic signal, inverse dynamics-based analyses, and computational musculoskeletal modeling. Progressing running speed from jogging to sprinting is mostly dependent on ankle and hip muscle performance. For speeds up to approximately 7.0 m/s, the dominant strategy is to push on the ground forcefully to increase stride length, and the major ankle plantar flexors (soleus and gastrocnemius) have a particularly important role in this regard. At speeds beyond approximately 7.0 m/s, the force-generating capacity of these muscles becomes less effective. Therefore, as running speed is progressed toward sprinting, the dominant strategy shifts toward the goal of increasing stride frequency and pushing on the ground more frequently. This strategy is achieved by generating substantially more power at the hip joint, thereby increasing the biomechanical demand on proximal lower-limb muscles such as the iliopsoas, gluteus maximus, rectus femoris, and hamstrings. Basic science knowledge regarding lower-limb muscle function during running has implications for understanding why sprinting performance declines with age. It is also of great value to the clinician for designing rehabilitation programs to restore running ability in young, previously active adults who have sustained a traumatic brain injury and have severe impairments of muscle function (eg, weakness, spasticity, poor motor control) that limit their capacity to run at any speed.
Expression and Function of Cannabinoid Receptors CB1 and CB2 and Their Cognate Cannabinoid Ligands in Murine Embryonic Stem Cells

Background Characterization of intrinsic and extrinsic factors regulating the self-renewal/division and differentiation of stem cells is crucial in determining embryonic stem (ES) cell fate. ES cells differentiate into multiple hematopoietic lineages during embryoid body (EB) formation in vitro, which provides an experimental platform to define the molecular mechanisms controlling germ layer fate determination and tissue formation. Methods and Findings The cannabinoid receptor type 1 (CB1) and cannabinoid receptor type 2 (CB2) are members of the G-protein coupled receptor (GPCR) family, that are activated by endogenous ligands, the endocannabinoids. CB1 receptor expression is abundant in brain while CB2 receptors are mostly expressed in hematopoietic cells. However, the expression and the precise roles of CB1 and CB2 and their cognate ligands in ES cells are not known. We observed significant induction of CB1 and CB2 cannabinoid receptors during the hematopoietic differentiation of murine ES (mES)-derived embryoid bodies. Furthermore, mES cells as well as ES-derived embryoid bodies at days 7 and 14, expressed endocannabinoids, the ligands for both CB1 and CB2. The CB1 and CB2 antagonists (AM251 and AM630, respectively) induced mES cell death, strongly suggesting that endocannabinoids are involved in the survival of mES cells. Treatment of mES cells with the exogenous cannabinoid ligand Δ9-THC resulted in the increased hematopoietic differentiation of mES cells, while addition of AM251 or AM630 blocked embryoid body formation derived from the mES cells. In addition, cannabinoid agonists induced the chemotaxis of ES-derived embryoid bodies, which was specifically inhibited by the CB1 and CB2 antagonists. Conclusions This work has not been addressed previously and yields new information on the function of cannabinoid receptors, CB1 and CB2, as components of a novel pathway regulating murine ES cell differentiation. This study provides insights into cannabinoid system involvement in ES cell survival and hematopoietic differentiation.
Hybrid RSS-DOA technique for enhanced WSN localization in a correlated environment

This paper proposes a modified hybrid method for WSN localization that combines Received Signal Strength (RSS) and Direction of Arrival (DOA) estimation based on MUSIC (Multiple Signal Classification) using circular antenna array with smoothing capability. Simulation results proves the enhanced performance obtained using the proposed hybrid method. This takes the form of successful detection of a mixture of correlated and uncorrelated signals at a higher accuracy and lower Root Mean Square Error (RMSE) in comparison with conventional method.
How Habit Limits the Predictive Power of Intention: The Case of Information Systems Continuance

Past research in the area of information systems acceptance has primarily focused on initial adoption under the implicit assumption that IS usage is mainly determined by intention. While plausible in the case of initial IS adoption, this assumption may not be as readily applicable to continued IS usage behavior since it ignores that frequently performed behaviors tend to become habitual and thus automatic over time. This paper is a step forward in defining and incorporating the "habit" construct into IS research. Specifically, the purpose of this study is to explore the role of habit and its antecedents in the context of continued IS usage. Building on previous work in other disciplines, we define habit in the context of IS usage as the extent to which people tend to perform behaviors (use IS) automatically because of learning. Using recent work on the continued usage of IS (IS continuance), we have developed a model suggesting that continued IS usage is not only a consequence of intention, but also of habit. In particular, in our research model, we propose IS habit to moderate the influence of intention such that its importance in determining behavior decreases as the behavior in question takes on a more habitual nature. Integrating past research on habit and IS continuance further, we suggest how antecedents of behavior/behavioral intention as identified by IS continuance research relate to drivers of habitualization. We empirically tested the model in the context of voluntary continued WWW usage. Our results support the argument that habit acts as a moderating variable of the relationship between intentions and IS continuance behavior, which may put a boundary condition on the explanatory power of intentions in the context of continued IS usage. The data also support that satisfaction, frequency of past behavior, and comprehensiveness of usage are key to habit formation and thus relevant in the context of IS continuance behavior. Implications of these findings are discussed and managerial guidelines presented.
Unified Volumes for Light Shaft and Shadow with Scattering

It is a challenge work to render natural lighting phenomena in real-time. A major reason is due to high computational expense to simulate the physical model of atmosphere scattering. Another is due to the lack of power and programmability in the graphic hardware. In this paper, we propose unified volumes representation for light shaft and shadow, which is an efficient method of simulating natural light shafts and shadows with atmospheric scattering effect. We give the analytic formula of light shaft without numerical integration and then make use of the current graphic hardware to implement the integral computation on each volume surface for scattering. Our approach can not only simulate the lighting effect with single light source but also multiple parallel light sources according to the physical model of skylight and sunlight. With acceleration of the GPU, we can generate realistic appearance with high frame rate satisfying real time application. It can possibly be used in current commercial game or other virtual reality systems.
Scaling in a Multispecies Network Model Ecosystem

A new model ecosystem consisting of many interacting species is introduced. The species are connected through a random matrix with a given connectivity . It is shown that the system is organized close to a boundary of marginal stability in such a way that fluctuations follow power law distributions both in species abundance and their lifetimes for some slow-driving (immigration) regime. The connectivity and the number of species are linked through a scaling relation which is the one observed in real ecosystems. These results suggest that the basic macroscopic features of real, species-rich ecologies might be linked with a critical state. A natural link between lognormal and power law distributions of species abundances is suggested.
Modeling and Design of a New Flexible Graphene-on-Silicon Schottky Junction Solar Cell

A new graphene-based flexible solar cell with a power conversion efficiency >10% has been designed. The environmental stability and the low complexity of the fabrication process are the two main advantages of the proposed device with respect to other flexible solar cells. The designed solar cell is a graphene/silicon Schottky junction whose performance has been enhanced by a graphene oxide layer deposited on the graphene sheet. The effect of the graphene oxide is to dope the graphene and to act as anti-reflection coating. A silicon dioxide ultrathin layer interposed between the n-Si and the graphene increases the open-circuit voltage of the cell. The solar cell optimization has been achieved through a mathematical model, which has been validated by using experimental data reported in literature. The new flexible photovoltaic device can be integrated in a wide range of microsystems powered by solar energy.
FT-FW: Efficient Connection Failover in Cluster-based Stateful Firewalls

Stateful firewalls are security solutions widely deployed in the Internet. These devices filter network traffic and keep track of the state of connections in order to make the deployment of several attacks, such as TCP resets, difficult. However, firewalls are critical equipments in the network schema since they introduce a single point of failure. Therefore, a failure may isolate networks, users and interrupt established connections. Current fault tolerant solutions mask failures by means of replication techniques based on physical redundancy and state propagation. However, these solutions do not suit well for stateful firewall scenarios since they reduce bandwidth throughput roughly, they require costful extra hardware or are stuck to wasteful and inflexible single primary-backup settings. In this work we detail FT-FW (fault tolerant firewall), a software-based transparent connection failover mechanism for stateful firewalls. Our solution has a negligible impact in terms of performance, as well as the fact that quick recovery from failures and fast responses to clients are guaranteed. The architecture is suitable for low cost off-the-shelf systems and no extra hardware is required.
Modeling Statistical Insensitivity: Sources of Suboptimal Behavior

Children acquiring languages with noun classes (grammatical gender) have ample statistical information available that characterizes the distribution of nouns into these classes, but their use of this information to classify novel nouns differs from the predictions made by an optimal Bayesian classifier. We use rational analysis to investigate the hypothesis that children are classifying nouns optimally with respect to a distribution that does not match the surface distribution of statistical features in their input. We propose three ways in which children's apparent statistical insensitivity might arise, and find that all three provide ways to account for the difference between children's behavior and the optimal classifier. A fourth model combines two of these proposals and finds that children's insensitivity is best modeled as a bias to ignore certain features during classification, rather than an inability to encode those features during learning. These results provide insight into children's developing knowledge of noun classes and highlight the complex ways in which statistical information from the input interacts with children's learning processes.
Distribution Entropy Boosted VLAD for Image Retrieval

Several recent works have shown that aggregating local descriptors to generate global image representation results in great efficiency for retrieval and classification tasks. The most popular method following this approach is VLAD (Vector of Locally Aggregated Descriptors). We present a novel image presentation called Distribution Entropy Boosted VLAD (EVLAD), which extends the original vector of locally aggregated descriptors. The original VLAD adopts only residuals to depict the distribution information of every visual word and neglects other statistical clues, so its discriminative power is limited. To address this issue, this paper proposes the use of the distribution entropy of each cluster as supplementary information to enhance the search accuracy. To fuse two feature sources organically, two fusion methods after a new normalization stage meeting power law are also investigated, which generate identically sized and double-sized vectors as the original VLAD. We validate our approach in image retrieval and image classification experiments. Experimental results demonstrate the effectiveness of our algorithm.
Do We Drive More Safely When Accidents are More Expensive? Identifying Moral Hazard from Experience Rating Schemes

A major shortcoming of the growing empirical work on asymmetric information is the inability to separately identify moral hazard from adverse selection. Abbring et. al. (2003) point out that dynamic insurance data can help here, by asking whether consumers have fewer claims when they are at a place in the “experience rating” scheme where additional claims are more expensive. However, in the French setting they study, this test boils down to asking whether there is negative state dependence in claims occurrence, and thus requires them to assume away all other forms of state dependence in claims. This paper overcomes this problem by considering U.S data, where claims fall off consumer records after three years, creating an “insurance event’ that changes a consumer’s position in the experience rating scheme with no simultaneous claim, and thus allowing identification of moral hazard even with fairly general controls for state dependence and unobserved heterogeneity. In addition, the U.S. data follow consumers for 10 years (vs. 1 in Abbring et. al) and contain a much wider range of claim price effects, both of which increase identification power. The paper’s core finding is a small, but statistically significant, moral hazard effect. This is made more convincing by the fact that the effect grows following a 1997 pricing change that increased the cost of additional claims relative to the first one. Finally, without the controls for state dependence in claims, this effect disappears. This suggests that the lack of evidence for moral hazard in previous work may have resulted from confounding the negative state dependence associated with moral hazard with some underlying source of positive state dependence in claims occurrence.
Poverty Transitions, Shocks, and Consumption in Rural Bangladesh: Preliminary Results from a Longitudinal Household Survey

This paper examines the correlates of poverty transitions and consumption per capita, using a new longitudinal data set from Bangladesh. It first examines the determinants of poverty transition categories (chronic poor, never poor, falling into poverty, moving out of poverty) as a function of household characteristics in the original survey round and shocks experienced by the household, controlling for unobserved community characteristics. The probability of being chronically poor (never poor) is negatively (positively) associated with years of schooling of the household head, the value of nonland assets, and the proportion of children below 15 and adults 55 and older in the baseline survey. However, the responsiveness of log per capita consumption does not differ significantly across the four poverty transition categories. Regressions on log per capita consumption also show that per capita consumption increases with years of schooling and assets. Higher proportions of children and older people are also significantly associated with lower per capita consumption, pointing to the importance of life-cycle and demographic factors in the creation and transmission of poverty. Having older household members also makes the household vulnerable to shocks such as illness, death, and property division. Illness shocks - in particular, the income foregone when an income earner falls ill - are important contributors to poverty. The impact of these and other shocks - such as dowry and wedding expenses, floods, and legal costs - in reducing consumption is shown to depend on the amount of land and assets owned by the household together with the schooling of the
Economic Growth in Egypt: Constraints and Determinants

Egypt accelerated its ongoing transition from a public sector dominated economy to a private sector led and market oriented economy after the collapse of oil prices in the mid-1980s. Some aspects of the economy, such as trade policy, have been substantially transformed since then whereas other aspects, such as public control of the financial sector, have experienced less change in substance. We examine some determinants of growth in Egypt since the mid-1980s using insights from both standard econometric techniques and a diagnostic approach proposed by Hausmann, Rodrik and Velasco (2004). We find that trends in government consumption, credit to the private sector and the average growth rate of OECD countries have been significant determinants of growth in Egypt in the past. We also present evidence that suggests that inefficiency of financial intermediation is a significant current constraint on growth.
Corporate Social Responsibility agenda for International Oil Companies (IOCs): new perspectives from stakeholders in the Niger Delta Region (NDR) of Nigeria

The discovery of oil in Nigeria in the 1950s has had extremes of both positive and negative impacts on Nigeria’s economic, political, social and environmental landscape particularly the Niger Delta Region (NDR). As a consequence, achieving an equitable distribution of oil revenue between all stakeholders has been a principal challenge. This lack of equitable distribution of revenues has led to instability and confrontation amongst and between some stakeholder groups. The qualitative study conducted with the major stakeholders in NDR was intended to explore the extant corporate social responsibility (CSR) practices of international oil companies (IOCs) and how they affect infrastructure development, capacity building and social welfare provision in NDR. It also investigated the current state of relationship between IOCs and other major stakeholders especially host communities in NDR. Stakeholders interviewed included IOCs, NNPC, host community leaders and subject matter experts The findings from the sample of different stakeholder groups (IOCs, government, host communities and subject matter experts) suggest that participants have good perception of the CSR practices of IOCs within the region. This awareness gave insight into the factors that shape CSR activities of IOCs in the region. The study also reveals that IOCs are using most of their CSR initiatives to address the infrastructure and social needs of host communities. Evidently, a number of infrastructure projects are linked to the CSR initiatives of some IOCs. Findings also point to a paradigm shift in the relationship between a number of IOCs and host communities in NDR. IOCs now engage host communities in almost all community development projects through the Global Memorandum of Understanding (GMOU). This initiative gives absolute control of community development projects to the Regional Development Committees (RDCs). Therefore there is not much complexity in identifying the needs of host communities. The study adds that there is evidence that some IOCs are more committed to the sustainable development of their host communities. This difference is witnessed in a number of specific projects linked to given IOCs. The major findings have been articulated in order to improve CSR practices of IOCs in NDR as well as encourage a friendly business environment. There is evidence from the II study that some host communities are not taking maximum advantage of the opportunities presented by IOCs in the region. Generally speaking, the face of government in NDR is the IOCs and this portends a major challenge for all the stakeholders. The study has provided a CSR roadmap and a sustainable development approach for the region that can be implemented through a concerted effort by the quartet of IOCs, host communities, NNPC and State/Local Governments. The framework can form the basis for future CSR practices of IOCs in the region and beyond.
An Intersecting Cortical Model Based Framework for Human Face Recognition

This paper introduces a novel method for human face recognition based on a simplified approach for the Pulse Coupled Neural Network (PCNN) Algorithm. The face image is introduced to the Intersecting Cortical Model (ICM) to be iterated 200 times, and then the time signals for the faces are compared to make a decision. Experimental results for human face recognition confirm that the proposed method lends itself to higher classification accuracy relative to existing techniques.
Flow Shear Stress Enhances the Proliferative Potential of Cultured Radial Glial Cells Possibly Via an Activation of Mechanosensitive Calcium Channel

Radial glial cells (RGCs) which function as neural stem cells are known to be non-excitable and their proliferation depends on the intracellular calcium (Ca2+) level. It has been well established that Inositol 1,4,5-trisphosphate (IP3)-mediated Ca2+ release and Ca2+ entry through various Ca2+ channels are involved in the proliferation of RGCs. Furthermore, RGCs line the ventricular wall and are exposed to a shear stress due to a physical contact with the cerebrospinal fluid (CSF). However, little is known about how the Ca2+ entry through mechanosensitive ion channels affects the proliferation of RGCs. Hence, we hypothesized that shear stress due to a flow of CSF boosts the proliferative potential of RGCs possibly via an activation of mechanosensitive Ca2+ channel during the embryonic brain development. Here, we developed a new microfluidic two-dimensional culture system to establish a link between the flow shear stress and the proliferative activity of cultured RGCs. Using this microfluidic device, we successfully visualized the artificial CSF and RGCs in direct contact and found a significant enhancement of proliferative capacity of RGCs in response to increased shear stress. To determine if there are any mechanosensitive ion channels involved, a mechanical stimulation by poking was given to individual RGCs. We found that a poking on radial glial cell induced an increase in intracellular Ca2+ level, which disappeared under the extracellular Ca2+-free condition. Our results suggest that the shear stress by CSF flow possibly activates mechanosensitive Ca2+ channels, which gives rise to a Ca2+ entry which enhances the proliferative capacity of RGCs.