Miracle-dz/UniFAR-FTUs huggingface dataset:
A hydrodynamic shear instability in stratified disks

We discuss the possibility that astrophysical accretion disks are dynamically unstable to non-axisymmetric distur- bances with characteristic scales much smaller than the vertical scale height. The instability is studied using three methods: one based on the energy integral, which allows the determination of a sufficient condition of stability, one using a WKB approach, which allows the determination of the necessary and sufficient condition for instability and a last one by numerical solution. This linear instability occurs in any inviscid stably stratified differential rotating fluid for rigid, stress-free or periodic boundary conditions, provided the angular velocity Ω decreases outwards with radius r. At not too small stratification, its growth rate is a fraction of Ω. The influence of viscous dissipation and thermal diffusivity on the instability is studied numerically, with emphasis on the case when d ln Ω/ dl nr = −3/2 (Keplerian case). Strong stratification and large diffusivity are found to have a stabilizing effect. The corresponding critical stratification and Reynolds number for the onset of the instability in a typical disk are derived. We propose that the spontaneous generation of these linear modes is the source of turbulence in disks, especially in weakly ionized disks.
Structure-based Analysis and Modularization of Ontologies

Defined as a problem-relevant, explicit and formal specification of a shared conceptualization, ontologies became a new hype in the context of the Semantic Web. Being a shared knowledge its potential for information integration in the large World Wide Web is promising. But either the reuse of existing ontologies or the matching of different ontologies is unavoidable for this integration. Therefore means for analyzing ontologies as well as modularization techniques for partial reuse are very important and a key for the success of information integration based on ontologies. Considering ontologies as networks of concepts connected through properties, this work makes use of network analysis techniques and graph measures. It aims at gaining insight to which extent structure based techniques can be modified so they are paying attention to the semantics inherent in ontologies. The expected contribution is a method and tool support for ontology engineers to analyze and modularize ontologies in a (semi-) automatic way. The main goal is to improve the (re-)usability and maintainability by increasing the understandability and allowing ontology engineers to refactor and reuse existing ontologies easily.
Adaptive autoregressive model with window extension via explicit geometry for image interpolation

In this paper, we propose a novel adaptive autoregressive (AR) model constructed with an explicit geometry based extended window for image interpolation. Geometric features are chosen as criterions to include more useful pixels. These features are estimated explicitly and guide the interpolation window to extend adaptively. To characterize the piecewise stationary of images, the patch-geodesic distance based similarity is proposed and modulated into the adaptive AR model. For increasing the precision of the parameter estimation, a weighted ridge regression based estimation is employed. With the estimation, the multicollinearity between parameters, which occurs in piecewise stationarity conditions, is eliminated. Experimental results demonstrate that the proposed method is better than or competitive with state-of-the-art interpolation methods in both objective and subjective quality evaluations.
Enhanced power saving mechanism for supporting broadcast/multicast services in IEEE 802.11 wireless LANs

In this paper, we present an extension of IEEE 802.11 power save mode standard to provide better performance for delivering broadcast and multicast traffic. The proposed protocol utilizes network coding and adaptive forward error correction to improve the performance in terms of delay and error rate. To employ the network coding and adaptive forward error correction, IEEE 802.11 frame format will be redefined. However, the proposed protocol is still compatible to legacy stations. The simulation in NS-3 has been implemented to illustrate the performance of the proposed protocol compared to the standard. It has been shown that the performance is better than the standard in terms of end-to-end delay and packet error rate.
Versão portuguesa do Cyber Dating Abuse Questionaire (CDAQ) – Questionário sobre Ciberabuso no Namoro (CibAN): Adaptação e propriedades psicométricas

Algumas manifestações de violência no namoro ocorrem através do uso das novas tecnologias, pelo que importa investigar esta tipologia de abuso apelidada internacionalmente de cyber dating abuse. O presente estudo procurou traduzir e adaptar, para a população portuguesa, o Cyber Dating Abuse Questionaire (CDAQ; Borrajo, Gámez-Guadix, Pereda, & Calvete, 2015), estudando as suas propriedades psicométricas. A versão portuguesa foi administrada a uma amostra de 272 estudantes, a grande maioria (87%) de sexo feminino e com uma média de idades de 28.41 (DP=7.02). A análise fatorial confirmatória revelou bons índices de ajustamento, permitindo confirmar o modelo fatorial do instrumento original constituído por quatro fatores correlacionados, dois relativos à vitimação por agressão direta e controlo e dois à perpetração dessas mesmas tipologias de violência. Adicionalmente, todos os fatores revelaram boa consistência interna. Ainda que os indicadores de prevalência de vitimação e perpetração por controlo (58.8% vs. 63.2%, respetivamente) se tenham revelado mais preponderantes comparativamente aos de vitimação e perpetração por agressão direta (18% vs. 14.7%), foi possível confirmar que estes dois tipos de ciberabuso íntimo constituem comportamentos entre os jovens portugueses estudantes universitários envolvidos/as em relações íntimas. As implicações práticas e empíricas futuras deste estudo são objeto de discussão neste trabalho.
MAC Enhancement for Gbps Throughput Achievement in Millimeter-Wave Wireless PAN Systems

A millimeter-wave (mmWave) wireless system is highly focused as a powerful mean enabling to perform very high data transmission. This paper proposes media access control (MAC) for mm Wave wireless system. Existing MAC has limits to achieve high data transmission over 1~2 Gbps by reasons of low frame transmission efficiency and high overhead of signal exchanges. In addition, the transmitting frames need to be protected in poor channel condition for high quality of service. The proposed MAC provides frame aggregation with unequal error protection (UEP) and block acknowledgement (Blk-ACK) / block negative acknowledgement (Blk-NAK) methods, which can solve the problems of existing MAC and guarantee the high quality of service. Theoretical throughput analysis shows that the proposed MAC has high throughput enhancement compared to the existing MAC and achieves MAC throughput over 2 Gbps.
On Qualified Cardinality Restrictions in Fuzzy Description Logics under Ëukasiewicz semantics

Fuzzy Description Logics have been proposed as a family of languages to describe vague or imprecise structured knowledge. This work deals with one of the less studied constructors, qualified cardinality restrictions, showing some counter-intuitive behaviours under Eukasiewicz semantics, and proposing a new semantics and the corresponding reasoning algorithm.
Independent and combined association of parity and short pregnancy with obesity and weight change among Indian women

Objective: To investigate association of parity and short pregnancy with obesity and weight change in Aggarwal Baniya women. Method: A cross-sectional analysis was carried out on a representative sample of 307 adult Aggarwal Baniya women aged 30 - 50 years (mean age: 38.7 ± 4.87) using multistage cluster sampling method. Weight, height, various skinfold thicknesses, waist and hip circumference were measured using standardized protocol. Various indices of obesity (BMI, WHR, WHtR, GMT) were calculated subsequently. Comparison groups were defined by the number of births (parity), short pregnancies and total pregnancies. Mean change in weight and other obesity markers were examined for each group separately. Correlation analysis was applied to see the association of childbearing on obesity. Linear regression was applied as an effective measure. Results: There was a gain in weight (3.16 kg) and increase in other obesity markers (BMI: 1.29 kg/m2; WC: 2.38 cm; HC: 3.83 cm) with each increase in each parity. Significant and positive correlation (p 2). Conclusion: Among other risk factors, high parity number may be associated with obesity in women. Therefore, interventions to prevent obesity should be targeted at women prior to initiation of childbearing. However, the impact of reproductive wastage in the form of short pregnancies on women’s obesity needs further exploration.
On compute-and-forward with feedback

We consider a Gaussian multiple-access channel where each user's message is identified with a vector of elements from a finite field, and the receiver's goal is to decode a linear combination of these finite field vectors. It is further assumed that each transmitter can causally observe the channel's output through a clean feedback link. We propose a novel coding scheme for this setup, which can be seen as an extension of the Cover-Leung scheme for the computation problem. This scheme is shown to achieve computation rates higher than the best known computation rates for the same scenario without feedback. In particular, for the symmetric two-user Gaussian multiple-access channel, the proposed scheme attains a symmetric computation rate greater than 1/2 log(3/4 + SNR).
The Functional Role of the Triceps Surae Muscle during Human Locomotion

Aim Despite numerous studies addressing the issue, it remains unclear whether the triceps surae muscle group generates forward propulsive force during gait, commonly identified as ‘push-off’. In order to challenge the push-off postulate, one must probe the effect of varying the propulsive force while annulling the effect of the progression velocity. This can be obtained by adding a load to the subject while maintaining the same progression velocity. Methods Ten healthy subjects initiated gait in both unloaded and loaded conditions (about 30% of body weight attached at abdominal level), for two walking velocities, spontaneous and fast. Ground reaction force and EMG activity of soleus and gastrocnemius medialis and lateralis muscles of the stance leg were recorded. Centre of mass velocity and position, centre of pressure position, and disequilibrium torque were calculated. Results At spontaneous velocity, adding the load increased disequilibrium torque and propulsive force. However, load had no effect on the vertical braking force or amplitude of triceps activity. At fast progression velocity, disequilibrium torque, vertical braking force and triceps EMG increased with respect to spontaneous velocity. Still, adding the load did not further increase braking force or EMG. Conclusions Triceps surae is not responsible for the generation of propulsive force but is merely supporting the body during walking and restraining it from falling. By controlling the disequilibrium torque, however, triceps can affect the propulsive force through the exchange of potential into kinetic energy.
In situ investigations of the structure and CO oxidation activity of Pd / Al 2 O 3

The catalytic oxidation of CO is of great practical importance and is e.g. used in commercial 3-way catalysts reducing automotive emissions. Depending on the reaction conditions different oxide species, e.g. chemisorbed oxygen, surface oxides or bulk oxide may be present on the surface. Despite several previous studies there are still open questions concerning the exact surface composition (which depends on the reaction conditions), the specific activity of the different phases, and their possible interplay [1].
The Pricing Puzzle: The Default Term Structure of Collateralised Loan Obligations

Ambivalence in the regulatory definition of capital adequacy for credit risk has recently steered the financial services industry to collateral loan obligations (CLOs) as an important balance sheet management tool. CLOs represent a specialised form of Asset-Backed Securitisation (ABS), with investors acquiring a structured claim on the interest proceeds generated from a portfolio of bank loans in the form of tranches with different seniority. By way of modelling Merton-type risk-neutral asset returns of contingent claims on a multi-asset portfolio of corporate loans in a CLO transaction, we analyse the optimal design of loan securitisation from the perspective of credit risk in potential collateral default. We propose a pricing model that draws on a careful simulation of expected loan loss based on parametric bootstrapping through extreme value theory (EVT). The analysis illustrates the dichotomous effect of loss cascading, as the most junior tranche of CLO transactions exhibits a distinctly different default tolerance compared to the remaining tranches. By solving the puzzling question of properly pricing the risk premium for expected credit loss, we explain the rationale of first loss retention as credit risk cover on the basis of our simulation results for pricing purposes under the impact of asymmetric information.
Draft Genome Sequence of an Antifungal Bacterium Isolated from the Breeding Environment of Dorcus hopei binodulosus

ABSTRACT Burkholderia sp. strain A1 was isolated from a decaying log present in the breeding environment of a stag beetle. The draft genome sequence indicates that strain A1 harbors many biosynthesis molecules, which have antimicrobial properties, and thus potentially eliminates the fungi by producing antifungal compounds, such as siderophores.
Mineral Revenues and Countercyclical Macroeconomic Policy in Kazakhstan

Kazakhstan’s sovereign wealth fund is used as the sole conduit for transferring mineral revenues to the state budget. This paper discusses alternative fiscal rules for use in governing these transfers and focuses in particular on a proposal to use transfers in a countercyclical manner. Though this idea is an excellent one in theory it suffers in practice from the near impossibility of identifying cycles in the national economy, the national budget, or in international oil prices in a time frame that would allow such a policy to be implemented. Numerical simulations show that using the NFRK for short run countercyclical purposes will almost inevitably lead to greater rather than lesser volatility due to the inability to forecast oil prices or the business cycle with any degree of accuracy. Other proposals such as that to allow NFRK investment in domestic assets have the potential to undermine one of the most important successes of macro policy management over the past decade: insulation of the domestic economy from the overheating that can be caused by a too-rapid expansion fueled by oil revenue. Overall, numerical simulation and consideration of various scenarios, including “worst case” or what might be considered remote possibilities shows that the NFRK as currently constituted is well able to deal with any transitory shocks of the nature modeled in this exercise. Given the reality of the extreme political pressures that can arise from sharp downturns beyond those of a “normal” business cycle, it is recommended that the current flexibility built into the NFRK rule be limited both in terms of the size of the shock that would trigger using it and in terms of the length of time such additional transfers might be allowed. Both theoretical and practical considerations suggest that building countercyclical response into the fiscal code in the form of "automatic stabilizers” be accomplished to the extent possible. The recommendations to generated by all of these considerations can be summed up as follows:First, implement “automatic stabilizers” to the extent possible. Second, limit the current 15% flexibility clause applying to the NFRK to make specific the size shock that would trigger its use and also to limit the length of time such additional funds could be transferred. Mineral Revenues and Countercyclical Macroeconomic Policy in Kazakhstan Steven Kyle Cornell University May 2013 I. Kazakhstan’s Economy and the Monetary/Fiscal Policy Mix
IGGSA Shared Tasks on German Sentiment Analysis (GESTALT)

We present the German Sentiment Analysis Shared Task (GESTALT) which consists of two main tasks: Source, Subjective Expression and Target Extraction from Political Speeches (STEPS) and Subjective Phrase and Aspect Extraction from Product Reviews (StAR). Both tasks focused on fine-grained sentiment analysis, extracting aspects and targets with their associated subjective expressions in the German language. STEPS focused on political discussions from a corpus of speeches in the Swiss parliament. StAR fostered the analysis of product reviews as they are available from the website Amazon.de. Each shared task led to one participating submission, providing baselines for future editions of this task and highlighting specific challenges. The shared task homepage can be found at https://sites.google. com/site/iggsasharedtask/.
Induction of Astrocyte Differentiation by Endothelial Cells

Here we have investigated the mechanisms that control astrocyte differentiation within the developing rat optic nerve. Astrocytes are normally generated by astrocyte precursor cells within the embryonic optic nerve. We show that there is a close temporal and spatial correlation between endothelial and astrocyte differentiation. We tested the potential role of endothelial cells in inducing astrocyte differentiation by developing an immunopanning method to highly purify endothelial cells from developing optic nerves. We show that the purified endothelial cells, but not other embryonic optic nerve cell types, strongly induce the differentiation of purified astrocyte precursor cells into astrocytes in vitro. Leukemia inhibitory factor (LIF) and LIF receptors have been implicated previously in astrocyte differentiation in vivo. We show that purified endothelial cells express LIF mRNA and that their ability to induce astrocyte differentiation is prevented by a neutralizing anti-LIF, but not anti-ciliary neurotrophic factor, antiserum. These findings demonstrate a role for endothelial cells in inducing astrocyte differentiation. The induction of astrocyte differentiation by endothelial cells makes sense phylogenetically, anatomically, and functionally, because astrocytes evolved concurrently with brain vasculature and ensheathe capillaries throughout the brain. The ability to purify and culture astrocytes and endothelial cells should provide an excellent model system for future studies of blood–brain barrier development.
Optical All-to-All Communication for SomeProduct Graphs ( Extended Abstract )

The problem of all-to-all communication in a network consists of designing directed paths between any ordered pair of vertices in a symmetric directed graph and assigning them minimum number of colours such that every two dipaths sharing an edge have distinct colour. We prove several exact results on the number of colours for some Carte-sian product graphs, including 2-dimensional (toroidal) square meshes of odd side, which completes previous results for even sided square meshes.
Performance evaluation of Operating Systems in the private cloud with XenServer hypervisor using SIGAR Framework

Virtualization Technology plays prominent role in the success of cloud computing because the delivery of services is simplified by providing a platform for optimizing complex IT resources in a scalable manner, which makes cloud computing more cost effective. Hypervisors give near native performance by negating virtualization overhead. XenServer is one of the hypervisors which give near native performance using para virtualization technique. It is encouraging to study how different Operating Systems (OSes) perform in a virtualized environment in the Private Cloud with XenServer hypervisor. Guest OSes do come in Paravirtualized and Hardware Virtualized flavours and in free and commercial versions. It is innovative idea to compare them from performance perspective to give an idea about their performance variations in different tests and also to analyse the results with respect to Para versus Hardware virtualization techniques. This paper conducts different performance tests with low, medium, high workloads and results are gathered using SIGAR API (System Information Gatherer and Reporter) and explains the behaviour of each operating system and gives the reasoning of results with the help of three different virtualization techniques namely Full Virtualization, Paravirtualization and Hardware Assisted Virtualization. In the experiment, CloudStack (open source cloud computing software) is used to create a private cloud (proprietary computing architecture deployed behind a firewall with full control over infrastructure), in which management server is installed on Ubuntu 12.04 - 64 bit operating system. XenServer hypervisor is installed on bare metal as a host in the cluster. The guest operating systems are installed on XenServer hypervisor and their respective performances have been evaluated in detail by using SIGAR Framework.
The insignificance of major mergers in driving star formation at z ≃ 2

We study the significance of major-merger-driven star formation in the early Universe, by quantifying the contribution of this process to the total star formation budget in 80 massive (M∗ > 10 10 M⊙) galaxies at z ≃ 2. Employing visually-classified morphologies from rest-frame V -band HST imaging, we find that 55 ±14 % of the star formation budget is hosted by non-interacting late-types, with 27 ±8 % in major mergers and 18 ±6 % in spheroids. Given that a system undergoing a major merger continues to experience star formation driven by other processes at this epoch (e.g. cold accretion, minor mergers), ∼27% is an upper limit to the major-merger contribution to star formation activity at this epoch. The ratio of the average specific star formation rate in major mergers to that in the non-interacting late-types is ∼2.2:1, suggesting that the enhancement of star formation due to major merging is typically modest, and that just under half the star formation in systems experiencing major mergers is unrelated to the merger itself. Taking this into account, we estimate that the actual majormerger contribution to the star formation budget may be as low as ∼15%. While our study does not preclude a major-merger-dominated era in the very early Universe, if the major-merger contribution to star formation does not evolve strongly into larger look-back times, then this process has a relatively insignificant role in driving stellar mass assembly over cosmic time.