Miracle-dz/UniFAR-FTUs huggingface dataset:
Determinants of the International Soybean Prices

The commodity prices have boosted in the last years and many possible causes have been mentioned (dollar weakness, China’s economic growth, oil prices, speculative bubble, agriculture productivity declining). Despite the recent crisis, some developing countries have presented a good performance in exports of these products. In particular, we focused on the soybean prices suggesting a simple theoretical model determining the equilibrium price. Then, using a dataset of monthly U.S. soybean prices, the exchange rate Chinese Yuan per Dollar and the Chinese real GDP from January 1981 to November 2010, we obtain a cointegration relationship supporting the theoretical model. The model and the empirical evidence suggest that the recent increase in soybean prices is mainly due to the appreciation of Chinese yuan against dollar, and the remarkable increase in the economic growth in China. Further results show that the forecasting performance of the proposed model showing that the present model is better forecasting one-month ahead than the ARIMA model. However, ARIMA model shows better performance forecasting 12-months ahead.
Classification of Daily Physical Activities from a Single Kinematic Sensor

This work was conducted in TIMC laboratory to develop methods able to monitor physical activities. In the framework of Health Smart Home, the purpose is to maintain and supervise elderly or fragile people at home. Activity and autonomy levels are important criteria to evaluate the health of the patient. The time spent in each postural state (lying, sitting, standing), the periods of walking and the number of postural transitions: sit-to-stand (StS), back-to-sit (BtS) give information about the patient's activity. The purpose of the current study is to detect these activities using an unique sensor made of three accelerometers, attached to the chest. First, this paper describes how each algorithm (posture, walk, postural transitions) works. Secondly, the results on real data are shown. An experiment with elderly subjects was carried out. Each subject performed daily activities (walking, sitting, lying down) while wearing the sensor
Public Spending Policies and Budgetary Balances: Evidence from Spanish Municipalities

Unlike the frequent research that analyzes the effects of various demographic, economic and political factors on fiscal deficits of governments, this research focuses on studying whether certain structures of public spending policies are associated with situations of fiscal imbalances. Using a panel data model with endogenous variables and taking into account various socio-economic factors as instruments, we have observed that the spending policies of Basic public services, Social protection and social promotion, Preferential services, and Promotion of economic activity have different significant effects on the position of the budgetary balance in the Spanish municipal governments.
Thermal Radiation Effect on the MHD Turbulent Compressible Boundary Layer Flow with Adverse Pressure Gradient, Heat Transfer and Local Suction

The combined effect of magnetic field, thermal radiation and local suction on the steady turbulent compressible boundary layer flow with adverse pressure gradient is numerically studied. The magnetic field is constant and applied transversely to the direction of the flow. The fluid is subjected to a localized suction and is considered as a radiative optically thin gray fluid. The Reynolds Averaged Boundary Layer (RABL) equations with appropriate boundary conditions are transformed using the compressible Falkner Skan transformation. The nonlinear and coupled system of partial differential equations (PDEs) is solved using the Keller box method. For the eddy-kinematic viscosity the Baldwin Lomax turbulent model and for the turbulent Prandtl number the extended Kays Crawford model are used. The numerical results show that the flow field can be controlled by the combined effect of the applied magnetic field, thermal radiation, and localized suction, moving the separation point, xs , downstream towards the plate’s end, and increasing total drag, D . The combined effect of thermal radiation and magnetic field has a cooling effect on the fluid at the wall vicinity. The combined effect has a greater influence in the case of high free-stream temperature.
Evolution of virulence: a unified framework for coinfection and superinfection.

Models of the evolution of parasite virulence have focused on computing the evolutionarily stable level of virulence favored by tradeoffs within a host and by competition for hosts, and deriving conditions under which strains with different virulence levels can coexist. The results depend on the type of interaction between disease strains, such as single infection (immunity of infected individuals to other strains), coinfection (simultaneous infection by two strains), and superinfection (instantaneous takeover of host by the more virulent strain). We present a coinfection model with two strains and derive the superinfection model as the limit where individuals are rapidly removed from the doubly-infectious class. When derived in this way, the superinfection model includes not only the takeover of hosts infected by the less virulent strain, but new terms which take into account the possibility of increased mortality of doubly-infected individuals. Coinfection tends to favor higher virulence and support more coexistence than the single infection model, but the detailed results depend sensitively on two factors: (1) whether and how the model is near the superinfection limit, and (2) the shape of the coinfection function (the function describing the rate at which a more virulent strain can infect a host). If the superinfection limit arises due to rapid mortality of doubly-infected hosts, there is a region of uninvadable virulence levels rather than coexistence. When the coinfection function is discontinuous, as in many previous models, neither the coinfection model nor the superinfection limit can support an evolutionarily stable virulence level. Piecewise differentiable and differentiable coinfection functions produce qualitatively different results, and we propose that these more general cases should be used to study evolution of virulence when other mechanisms like space, population dynamics, and stochasticity interact.
A Malware Signature Extraction and Detection Method Applied to Mobile Networks

The rapid development of mobile phone networks has facilitated the need for better protection against malware. Malware detection is a core component of a security system protecting mobile networks. In this paper, we describe a system for detecting malware within the network traffic using malware signatures. Our system contains two key components. The first one automatically extracts a set of signatures from existing malware samples. In particular, we reduce the number of signatures by using a common signature for a malware and its variants. In addition, we minimize the total false alarm rate of malware detection by extracting signatures that are most uncommon within mobile network traffic. The second one is an efficient method that scans the network traffic using a hash table and sub-signature matching. Our evaluation on Symbian viruses show that our system detects existing malware and their new variants within the network traffic efficiently.
Working Paper 133 - Monetary Policy Transmission, House Prices and Consumer Spending in South Africa: An SVAR Approach

The study used a structural vector autoregressive approach to estimate and quantify the percentage decline in consumption expenditure, which can be attributed to changes in housing wealth, after monetary policy tightening. The effects are separated using a disaggregated Absa house price data, namely all-size, large-size and medium-size and small-size house prices.The results suggest that at the peak of the interest rate effects on consumption the combined effect of housing wealth and credit extension changes, following a monetary policy tightening, was a decline of 9.8 per cent in all-size, 3.7 per cent in small-size, 4.7 per cent in medium-size and 5.3 per cent in large-size houses. The findings indicate heterogeneity in the transmission of interest rate effects operating through housing wealth and the credit channel. Moreover, we reached the same conclusion after modifying the baseline model by adding the restrictions that house price also respond to both aggregate demand and aggregate supply variables. Lastly, the differences between the counterfactual consumption and the baseline consumption responses, provided little support for the assumption that the housing wealth channel is the dominant source of monetary policy transmission to consumption.This paper thus provided an understanding of the indirect channels through which monetary policy influences real variables by focusing on monetary policy transmission to consumption via house prices. We showed interest rate effects, working through both housing wealth and the credit channel, influence real spending. Thus, interest rate effects operating through housing wealth and the credit channel are felt differently by the four house categories. Moreover, the differences between the consumption impulse responses from the counterfactual and baseline scenarios provide little support that combined house wealth and credit effect channels are the dominant sources of monetary policy transmission to consumption. These findings suggest that the direct effects of high interest rates on consumption appear to be more important in transmitting monetary policy to the economy than through the indirect effects. Hence, monetary policy tightening can only marginally weaken inflationary pressures arising from excessive consumption operating through housing wealth and the credit channel.
Extreme Value distribution for singular measures

In this paper we perform an analytical and numerical study of Extreme Value distributions in discrete dynamical systems that have a singular measure. Using the block maxima approach described in Faranda et al. [2011] we show that, numerically, the Extreme Value distribution for these maps can be associated to the Generalised Extreme Value family where the parameters scale with the information dimension. The numerical analysis are performed on a few low dimensional maps. For the middle third Cantor set and the Sierpinskij triangle obtained using Iterated Function Systems, experimental parameters show a very good agreement with the theoretical values. For strange attractors like Lozi and Hènon maps a slower convergence to the Generalised Extreme Value distribution is observed. Even in presence of large statistics the observed convergence is slower if compared with the maps which have an absolute continuous invariant measure. Nevertheless and within the uncertainty computed range, the results are in good agreement with the theoretical estimates. The existence of extreme value laws for dynamical systems preserving an absolutely continuous invariant measure or a singular continuous invariant measure has been recently proven if strong mixing properties or exponential hitting time statistics on balls are satisfied. In our previous work we have shown that there exists an algorithmic way 1 ar X iv :1 10 6. 22 99 v1 [ m at h. D S] 1 2 Ju n 20 11 to study extrema by using a block-maxima approach for dynamical systems which possess an absolutely continuous invariant measure and satisfy certain mixing properties. In this work we test our algorithm for maps that do not have an absolutely continuous invariant measure showing that the cumulative distribution function of maxima is related to the scaling of the measure of a ball centered around generic points. The scaling exponent turns out to be the Hausdorff dimension of the measure (also known as information dimension). Even if we cannot estimate analytically the asymptotic behavior of the measure of the balls, the agreement with the numerical simulations we have carried out for different maps suggests the validity of our proposed scaling in terms of the information dimension. Our conjecture has been tested with numerical experiments on different low dimensional maps such as the middle third Cantor set, the Sierpinskij triangle, Iterated Function System (IFS) with non-uniform weights and strange attractors such as Lozi and Hénon. In all cases considered, there is a good agreement between the theoretical parameters and the experimental ones although, in case of strange attractors which exhibit multifractal structures, the convergence is slower. To perform the numerical simulations it has been used the L-moments procedure in order to overcome the difficulties of dealing with a singular continuous invariant measure.
Developmental origin and kit‐dependent development of the interstitial cells of cajal in the mammalian small intestine

Interstitial cells of Cajal (ICCs) form a network of cells between the external longitudinal and circular muscle layers at the level of the Auerbach's plexus in the mammalian small intestine. These cells express the Kit receptor tyrosine kinase and are essential for intestinal pacemaker activity. W mutant mice carrying structural mutations in the Kit gene lack both the network of ICCs and intestinal pacemaker activity. We were interested in the developmental origin of the cells that make up the network of ICCs. In addition, the specific stages of ICC development that require a functional Kit receptor have not been characterized. We show that ICCs originate from mesenchymal progenitor cells that coexpress both Kit and smooth muscle myosin heavy chain, a marker specific for smooth muscle, during embryogenesis. ICC and longitudinal smooth muscle lineages begin to diverge late in gestation. Embryos homozygous for the regulatory Wbanded (Wbd) mutation do not express Kit in these mesenchymal progenitor cells. Nevertheless, Wbd/Wbd mice display a normal network of ICCs and normal smooth muscle layers at postnatal day 5 (p5). Adult Wbd/Wbd mice lack a functional ICC network and intestinal pacemaker activity due to a failure of the ICCs to increase in numbers after p5. These data suggest a common developmental origin of the ICCs and the longitudinal smooth muscle layers in the mammalian small intestine and show that Kit expression is necessary for the postnatal development and proliferation of ICCs but not for the initial cell lineage decision toward an ICC fate during embryogenesis or for smooth muscle development. Dev. Dyn. 1998;211:60‐71. © 1997 Wiley‐Liss, Inc.
Reduced snow cover alters root-microbe interactions and decreases nitrification rates in a northern hardwood forest.

Snow cover is projected to decline during the next century in many ecosystems that currently experience a seasonal snowpack. Because snow insulates soils from frigid winter air temperatures, soils are expected to become colder and experience more winter soil freeze-thaw cycles as snow cover continues to decline. Tree roots are adversely affected by snowpack reduction, but whether loss of snow will affect root-microbe interactions remains largely unknown. The objective of this study was to distinguish and attribute direct (e.g., winter snow- and/or soil frost-mediated) vs. indirect (e.g., root-mediated) effects of winter climate change on microbial biomass, the potential activity of microbial exoenzymes, and net N mineralization and nitrification rates. Soil cores were incubated in situ in nylon mesh that either allowed roots to grow into the soil core (2 mm pore size) or excluded root ingrowth (50 μm pore size) for up to 29 months along a natural winter climate gradient at Hubbard Brook Experimental Forest, NH (USA). Microbial biomass did not differ among ingrowth or exclusion cores. Across sampling dates, the potential activities of cellobiohydrolase, phenol oxidase, and peroxidase, and net N mineralization rates were more strongly related to soil volumetric water content (P < 0.05; R2 = 0.25-0.46) than to root biomass, snow or soil frost, or winter soil temperature (R2 < 0.10). Root ingrowth was positively related to soil frost (P < 0.01; R2 = 0.28), suggesting that trees compensate for overwinter root mortality caused by soil freezing by re-allocating resources towards root production. At the sites with the deepest snow cover, root ingrowth reduced nitrification rates by 30% (P < 0.01), showing that tree roots exert significant influence over nitrification, which declines with reduced snow cover. If soil freezing intensifies over time, then greater compensatory root growth may reduce nitrification rates directly via plant-microbe N competition and indirectly through a negative feedback on soil moisture, resulting in lower N availability to trees in northern hardwood forests.
The relative age effect in soccer: A match-related perspective

Asymmetries in the distributions of birth dates in senior professional and youth soccer players have been interpreted as evidence for systematic discrimination against individuals born shortly before the cut-off date in assigning youth to specific age groups. This concept is known as the “relative age effect”. The results of a longitudinal study of birth date distritubions of 2757 semi-professional and amateur senior soccer players in Belgium are presented. Records for competitive games were available in official statistics provided by the Royal Belgian Football Association. The chi-square statistic was used to examine differences between observed and expected birth date distributions. Regression analyses indicated a shift of bias when two different start dates were compared. Players born in the early part of the new age band (January to March) were over-represented compared with players born late in the new selection period (October to December). However, players with birthdays at the start of the old selection year (August) were still represented. In a retrospective analysis of 2138 players, variables indicative of match involvement, number of selections for matches, and time played were examined in relation to the relative age effect. The group of semi-professional and amateur senior soccer players born in the first quarter of the selected age band received more playing opportunities. Comparisons of birth date distributions (traditional approach to relative age effect) with match-related variables gave similar, though not entirely consistent, results. However, there were no differences for the mean number of selections and for playing minutes between players born at the start or the end of the selection year. Our findings suggest that match-based variables may provide a more reliable indication of the relative age effect in soccer.
Carbon Nanotube-Based Hydrogen Gas Sensor Electrochemically Functionalized with Palladium

Palladium (Pd) has been widely employed for conventional hydrogen sensors due to the catalytic nature. Pd has been incorporated also with carbon nanotube (CNT) gas sensors for hydrogen sensing. In this study, a liquid-phase electrochemical reaction was proposed to realize a simple and inexpensive fabrication method of a Pd-functionalized CNT hydrogen sensor. The single-walled CNTs were trapped onto a microelectrode under positive dielectrophoresis. The CNT-retaining microelectrode was immersed in a palladium acetate solution together with a graphite rod. DC voltage was applied between the microelectrode (cathode) and the graphite rod (anode) so that palladium acetate could be reduced and catalytic Pd could be electrodeposited on the CNT surface. The CNT sensor could reversibly respond to hydrogen gas in the air in the range of 0.01 % -1 % concentration at room temperature. It was also demonstrated that the Pd-functionalized CNT gas sensor could be fabricated just by dipping the CNT-retaining microelectrode into an aqueous Pd salt solution without applying DC voltage (electroless redox reaction).
Price Indexes for Commercial and Office properties: An Application of the Assessed Value Method

This study constructs a nonresidential, constant-quality price index, based on the assessed- value approach, and adjusts for the possibility for sample selection bias. The sample consists of a large sample of commercial and office properties located in Charlotte, N.C. during 1981-1994. Statistical tests for sample selection bias suggest that bias is present in the office sample, but not in the commercial property sample. For office properties, the selection process is such that higher prices prevail for equivalent office properties that sell relative to those that do not sell. The estimated price indexes indicate average appreciation rates of 16.2% for commercial property and 9.9% for office property.
The changing practice of thoracic epidural analgesia in the United Kingdom: 1997–2004

The clinical governance framework and medico‐legal climate in the United Kingdom has changed significantly in the past 7 years. We used a postal questionnaire to survey thoracic epidural practice in the United Kingdom in 1997 and repeated this survey in 2004. The response rate to both surveys was 59–60%. There has been considerable change in respect of taking specific consent for thoracic epidural analgesia (24% in 1997, 74% in 2004), awake epidural cannulation (40% in 1997, 84% in 2004), availability of an acute pain service (47% in 1997, 95% in 2004) and HDU‐only nursing of patients (63% in 1997, 30% in 2004). Of the 2004 respondents, < 1% used the newer, less toxic local anaesthetics, 49% would consider inserting a thoracic epidural in patients receiving clopidogrel, and 34% would consider inserting a thoracic epidural in patients receiving both aspirin and clopidogrel. A central register of thoracic epidural complications would assist in further developing practice.
BK channel subunit composition modulates molecular tolerance to ethanol.

BACKGROUND The large conductance calcium-activated potassium channel (also called BK channel or Slo channels) is a well-studied target of alcohol action, and plays an important role in behavioral tolerance. METHODS Using patch clamp electrophysiology, we examined human BK channels expressed in HEK293 cells to test whether tolerance to ethanol occurs in excised patches and whether it is influenced by subunit composition. Three combinations were examined: hSlo, hSlo + beta(1), and hSlo + beta(4). RESULTS The 2 components of BK alcohol adaptation (Component 1: rapid tolerance to acute potentiation, and Component 2: a more slowly developing decrease in current density) were observed, and varied according to subunit combination. Using a 2-exposure protocol, Component 1 tolerance was evident in 2 of the 3 combinations, because it was more pronounced for hSlo and hSlo + beta(4). CONCLUSIONS Thus, rapid tolerance in human BK occurs in cell-free membrane patches, independent of cytosolic second messengers, nucleotides or changes in free calcium. Alcohol pretreatment for 24 hours altered subsequent short-term plasticity of hSlo + beta(4) channels, suggesting a relationship between classes of tolerance. Finally, Component 2 reduction in current density showed a striking dependency on channel composition. Twenty-four hour exposure to 25 mM ethanol resulted in a down-regulation of BK current in hSlo and hSlo + beta(4) channels, but not in hSlo + beta(1) channels. The fact that hSlo + beta(1) channels show less sensitivity to acute challenge, in conjunction with less Component 1 and Component 2 tolerance, suggests subunit composition is an important factor for these elements of alcohol response.