Miracle-dz/UniFAR-FTUs huggingface dataset:
5K-6 Experimental and Numerical Studies on Lamb Waves Conversion in a Waveguide with Gaussian Section Variation

This work deals with the conversion of a Lamb wave propagating in a Duraluminium elastic waveguide, when it reaches a Gaussian thickness variation area located between two areas of constant and equal thickness. The varying section area is wide compared to the used wavelengths. Two kinds of waveguides having the same Gaussian thickness variation width but of different height (strong and slow section variation) are studied, allowing the comparison for a given incident Lamb wave. Experimental and numerical studies are performed to provide the behaviour of the guided wave inside the area of varying thickness, and the conversion of this wave into other Lamb waves that are transmitted outside this area. The experimental study is conducted with a contact transducer for the excitation. For several positions on the waveguide, a laser velocimeter is used for the measurement of the time depending normal displacement on the plate surface due to the wave travelling. The signal processing used double space-time FFT and spatial sliding windows FFT. Experimental results show that the incident S0 Lamb wave is converted into adiabatic wave inside the Gaussian varying thickness zone for the both waveguides. Outside this area, the transmitted Lamb waves are strongly depending on the waveguide shape and on frequency. This transmission into Lamb waves is experimentally quantified versus frequency for the strong varying section waveguide. These experimental results are successfully compared to a numerical study based on the Finite Element Method
Stock returns and real activity: is there still a connection?

Several studies published in the early 1990s found that a large fraction of stock return variations can be explained by future values of measures of real activity in the United States by using data samples from the 1950s to the 1980s. This paper presents evidence that the relation does not hold up any more during the most recent stock market boom since the early 1980s indicating that stock returns ceased to lead real economic activity. Therefore, the current stock market boom seems to be fundamentally different from the first stock market boom after World War II from the late 1940s to the mid-1960s, when the stock market was clearly leading real activity. A possible explanation of our results is the existence of bubbles or fads which make movements of stock prices more independent from subsequent changes in real activity.
Simultaneous Determination of Insider Ownership, Debt, and Dividend Policies

Abstract We examine the determinants of cross-sectional differences in insider ownership, debt, and dividend policies. These policies are related not only directly, but also indirectly, through their relationship with operating characteristics of firms. To distinguish these effects, we examine the determinants of the three policy choices within a system of equations. Our empirical results support the hypothesis that levels of insider ownership differ systematically across firms. Further, high insider ownership firms choose lower levels of both debt and dividends. Finally, the effects of profitability, growth, and investment spending on debt and dividend policy support a modified “pecking order” hypothesis.
Anchor Loss in Hemispherical Shell Resonators

Micromachined hemispherical shell resonators (HSRs) can be used in high accuracy vibratory gyroscopes. These resonators need to have very low energy loss to achieve very high quality factor. Energy might be lost through the anchor, fluid-structure interaction, thermoelastic dissipation, phonon–phonon and phonon–electron interactions, and the resonator surface. This paper investigates energy loss through the anchor of HSRs using a numerical approach. To numerically determine wave radiation from the anchor to the infinite substrate, a perfectly matched layer is used around a finite substrate. Anchor loss investigations in HSRs are classified into four categories. First, the effects of shell properties—material, geometry, and imperfections—are investigated. Second, the relationships between anchor loss and properties of the stem, such as material, geometry, and stem-shell misalignments, are studied. Third, the effects of substrate characteristics—substrate material, attachment material between the stem and substrate, and attachment configuration of the substrate and stem—are investigated. Finally, the effects of external motions, such as shock and rotation, are analyzed. It is found that anchor loss in HSRs strongly depends on the shell, stem, and substrate properties. This study also shows that any imperfection in the shell or any misalignment between the shell and stem increases anchor loss by orders of magnitude. [2016-0115]
Advances and Challenges in Entrepreneurship Education

Recent global economic crisis has increasingly demanded bold action from organizations. If these organizations fail to respond appropriately, entrepreneurs will develop new meaningful solutions to the complex and dynamic needs of the market. Guidance of many of these future entrepreneurial leaders falls on the shoulders of those in higher education. My goal in this paper is to suggest a shift toward a more enacted approach in the delivery of this guidance. This suggestion represents my own interpretation, is not generalizable in all environments, and should therefore be viewed with caution.
Trend breaks and the fisher hypothesis in canada and the United States

Using the sequential estimation methodology developed by Banerjee, Lumsdaine and Stock (Journal of Business and Economic Statistics, 10(3), 271–87, 1992), Zivot and Andrews (Journal of Business and Economic Statistics, 10(3), 251–70, 1992) and extended by Lumsdaine and Papell (Review of Economics and Statistics, 79(2), 212–18, 1997), empirical evidence is found consistent with the hypothesis that the 90-day Treasury Bill rate and the inflation rate in Canada and the US are stationary around a deterministic trend with two breaks. When the breaks are filtered out, the data is consistent with partial long-run adjustment of the nominal interest rate to an inflation shock, but not of the size predicted by the Fisher Effect.
Peripheral development of B cells in mouse and man

Summary: In man and in mouse, B‐cell maturation occurs in steps, first in the bone marrow from hematopoietic precursors to immature/transitional B cells, then in the periphery from transitional to fully mature B cells. Each developmental step is tightly controlled by the expression and function of the B‐cell receptor (BCR) and by the ability to interact with the microenvironment. Mature B cells collaborate with T cells in the adaptive immune response, leading to the production of high‐affinity antibodies. This response is very accurate, but slow. Immediately after pathogen entry, however, antibodies already present in the serum reinforce the innate immune response and contribute to the first‐line defense against infection. Low‐affinity natural antibodies are produced by B‐1a B cells in the mouse and immunoglobulin M (IgM) memory cells in man. These antibodies represent an immediate protection against all microorganisms and the only one against encapsulated bacteria. B‐1a and IgM memory B cells may function as a link between the innate and adaptive immune response and thus perform a primordial B‐cell function.
CT differentiation of tuberculous peritonitis and peritoneal carcinomatosis.

OBJECTIVE The purpose of this study was to determine the potential of CT for distinguishing tuberculous peritonitis from peritoneal carcinomatosis in 135 clinically or pathologically proven cases. MATERIALS AND METHODS Abdominal CT scans in 135 patients of tuberculous peritonitis (n = 42) and peritoneal carcinomatosis (n = 93) with documented omental, mesenteric, or peritoneal pathology were retrospectively reviewed. CT findings were evaluated in each group of patients for the morphologic appearance of mesenteric or omental abnormalities as well as for visualization of the spleen and liver, the lymph nodes, and ascites. Statistical comparisons using multivariate logistic regression analysis were performed to adjust for the differences in CT findings between the two groups. RESULTS Mesenteric changes were more commonly seen in patients with tuberculous peritonitis (98%) than in patients with peritoneal carcinomatosis (70%) (p < .01). Micronodules (less than 5 mm in diameter) were noted in approximately one half of patients with tuberculous peritonitis or peritoneal carcinomatosis, but macronodules (> or = 5 mm in diameter) were much more frequently seen in patients with tuberculous peritonitis (52%) than in patients with peritoneal carcinomatosis (12%) (p < .01). The omentum appeared to be more irregularly infiltrated in peritoneal carcinomatosis patients (p < .01). The thin omental line covering the infiltrated omentum was seen in 13 patients with tuberculous peritonitis but in only four patients with peritoneal carcinomatosis (p < .01). In peritoneal or extraperitoneal masses in patients with tuberculous peritonitis, a low-density center was seen in 18 cases (43%) and calcification was noted in six cases (14%). The prevalences of splenomegaly and splenic calcification were higher in patients with tuberculous peritonitis. Using multivariate analysis, we calculated the sensitivity of CT for predicting tuberculous peritonitis and peritoneal carcinomatosis as 69% and 91%, respectively. CONCLUSION Although most CT findings that we analyzed overlap these diseases, using a combination of CT findings increased our ability to distinguish tuberculous peritonitis from peritoneal carcinomatosis.
The role of complement and Toll‐like receptors in organ transplantation

The innate immune system not only participates in host defence but also contributes to the control of adaptive immune responses. Complement and Toll‐like receptors (TLR) are key components of innate immunity. Emerging evidence suggests their activation is involved in all major aspects of transplantation. This paper reviews the current understanding of how the complement and TLR on impact transplant injury.
Nicotine Accelerates Diabetes-Induced Retinal Changes

Abstract Purpose: To investigate the effects of nicotine on retinal alterations in early-stage diabetes in an established rodent model. Materials and Methods: Sprague–Dawley rats were examined using a combination of confocal scanning laser ophthalmoscopy and spectral domain optical coherence tomography to determine changes in retinal structure in response to nicotine exposure, diabetes and the combined effects of nicotine and diabetes. Diabetes was induced by a single injection of 65 mg/kg streptozotocin and nicotine injections were administered subcutaneously daily. Retinal thickness in the superior, inferior, nasal and temporal quadrants were determined based on the spectral domain optical coherence tomography (SD-OCT) volume scans (20° × 20°) centered on the optic disc. Segmentation of discrete retinal layers was performed on a subset of SD-OCT cross-sections to further examine changes in each treatment group. Survival of neurons within the ganglion cell layer (GCL) was assessed by confocal morphometric imaging. Results: The control group did not experience any significant change throughout the study. The nicotine treatment group experienced an average decrease in total retinal thickness (TRT) of 9.4 µm with the majority of the loss localized within the outer nuclear layer (ONL) as determined by segmentation analysis (p < 0.05). The diabetic group exhibited a trend toward decreased TRT while segmentation analysis of the diabetic retinopathy (DR) group revealed significant thinning within the ONL (p < 0.05). The combination of nicotine and diabetes revealed a significant increase of 8.9 µm in the TRT (p < 0.05) accompanied by a decrease in the number of GCL neurons. Conclusions: We demonstrated significant temporal changes in retinal morphology in response to nicotine exposure, diabetes and with the combined effects of nicotine and diabetes. These findings may have implications in determining treatment strategies for diabetic patients using products containing nicotine, such as cigarettes, smokeless tobacco, electronic cigarettes or smoking cessation products.
Why are some favourite-longshot biases positive and others negative?

Most studies of both pari-mutuel and fixed-odds betting markets have shown a systematic tendency for the expected return to bets at lower odds to exceed those at higher odds. Some work, however, has revealed in certain markets the absence or even reversal of this bias. We present a model which distinguishes two separate types of bettor, and use this to demonstrate how transactions costs, the extent of public information, and consumption benefits of betting can explain the disparities. Our empirical evidence, taken from a fixed-odds market, lends support to our theoretical conclusions.
The influences of entrepreneurial orientation on product advantage and new product success

Purpose – The purpose of this paper is to improve understanding of what makes or breaks a new product by exploring the direct and indirect impacts of the three dimensions of entrepreneurial orientation (EO) – innovativeness, risk taking and proactiveness – on product advantage and new product success (NPS). Design/methodology/approach – Based on the literature reviewed, theoretical relationships among five constructs and relevant hypotheses were developed and subsequently tested using data collected from 244 electronics manufacturers in China.Findings – The results show that the three dimensions of EO and product advantage are the driving antecedents of NPS. Moreover, it is confirmed that the relationships between the three dimensions of EO and NPS are mediated by product advantage and the relationship between risk taking and product advantage is moderated by innovativeness and proactiveness.Originality/value – Literature about the interplay among the three dimensions of EO and NPS are often disparate and .
Impact of defence spending on economic growth in Africa: The Nigerian case

This paper examines the relationship between defence burden and real gross domestic products in Nigeria, using annual time series data. This study uses Johansen’s Cointegration approach to investigate the relationship between government’s military expenditure (defence burden) and real gross domestic products, among other variables. In light of the lingering controversy on military expenditure and growth nexus, this paper contributes to the existing literature using time-series data from Nigeria, a country with high military spending over the years to re-investigate the impact of military expenditures on economic growth and the direction of causality between military spending and economic growth. Specifically, this study discusses the long run relationship between military expenditure and economic growth using Johansen cointegration approach. The key variables used in the study include: military burden (military expenditure), real GDP, real education expenditure, real health expenditure. The nature of the relationship that exists between military expenditure and economic growth as well as the cointegrating vector, taking into cognizance all other variables is focus of this paper. The results of the study show that increased defence burden is harmful to the Nigerian economy, and there exists a negative long-run relationship between defence burden and increase in the growth of real gross domestic products, the impact of defence burden remains negative both in the short-run and long-run respectively. It is not sufficient to have cuts in military expenditure, but such reallocation from defence should be directed towards productive investment in other sectors of the economy in order to generate economic prosperity and enhance the welfare of the citizens. Implications of having a negative effect of defence burden on growth rate of real Gross Domestic Products result in crowding-out of private sector investment, retards economic progress or growth rate of real gross domestic products, and therefore, is an ineffective tool to stimulate the growth of the economy in Nigeria. Military expenditure cannot be an effective tool of fiscal policy (government revenue and expenditure to regulate the economy), from the results of the study both short-run and long-run impact are negative, hence, the role of military sector should be limited to the maintenance of internal law and order as well as the defence of the country against any form of external aggression. This study will be of immense significance towards shaping policies that relate to military spending in Nigeria.
Impact of small‐scale irrigation on household poverty: empirical evidence from the Ambo district in Ethiopia

A study was conducted in the Ambo district of western Ethiopia in 2006 to understand the poverty reduction impacts of small‐scale irrigation development, using the Indris irrigation system as a case study. The study was based on a survey of representative farm households with and without access to irrigation. The total sample size for the study was 222 (107 households with access to irrigation and 115 without). Data were analysed using descriptive statistics, the Foster, Greer and Thobeck poverty indices, and Heckman's selectivity model. Results indicate that the incidence, depth, and severity of poverty are significantly lower among those farm households with access to irrigation. In addition to irrigation, other variables such as farm size, livestock holding size, land productivity, and family size significantly influence the level of household consumption expenditure. However, the proportion of poor people in the overall sample, notwithstanding access to irrigation, is alarmingly high, indicating the deep‐rooted and critical situation of poverty in rural Ethiopia. Copyright © 2009 John Wiley & Sons, Ltd.
Mitigation of intercarrier interference in OFDM systems over slow fading channels based on the EM algorithm

Orthogonal Frequency Division Multiplexing (OFDM) is a transmission technique that allows simple multipath channel equalization schemes. On the other side it is sensitive to frequency offset at the local oscillator, phase noise and Doppler shift which may destroy the orthogonality among subcarriers causing Inter Carrier Interference (ICI). It is possible to represent this interference in the frequency domain by means of an ICI matrix. Since these types of errors greatly affect the performance of an OFDM system, estimation of this matrix is crucial. In this work we propose an iterative method to mitigate the interference among subcarriers exploiting the presence of pilot tones in the frequency domain. It can be explained referring to the Expectation-Maximization (EM) paradigm. The proposed technique is very effective in multipath fading channels and a simplified version is also introduced in case of AWGN channel with frequency offset at the local oscillator. Simulation results show that the presented algorithm converges very quickly and looks promising to be used in actual implementations.
The Failure of the Sport7 TV-channel: Controversies in a Business Network

During 1996, TV viewers in the Netherlands witnessed the rise and fall of Sport7: a dedicated sports TV channel. Apparently, Sport7 did not succeed to become part of the business network of television and sports. This paper describes and explains why the venture failed. It builds on earlier insights from research on the outcomes of joint ventures and the business networks perspective. These insights are combined and utilized within the framework of the theory of social becoming (Sztompka, 1991). As such, for a new venture like Sport7, the outcome depends on the settlement of a number of controversies that arise with the establishment of a new actor in an existing business network. In the case of Sport7, the settlement of these controversies appeared to go against this new venture, ultimately leading to the demise of this new TV channel.
Which family factors predict children's externalizing behaviors following discharge from psychiatric inpatient treatment?

OBJECTIVE Parents' behavior management practices, parental stress, and family environment are highly pertinent to children's conduct problems. Preadolescents' psychiatric hospitalization usually arises because of severe conduct problems, so the relationships of family-related variables to postdischarge functioning warrant investigation. This study examined postdischarge clinical course and select family factors to model outcomes via a) predictors measured at admission, b) predictors measured concurrently with outcome, and c) changes in predictor values from admission through follow-up. METHOD In a prospective follow-up of 107 child psychiatry inpatients, caregivers completed rating scales pertaining to their child's behavior, parenting practices, parenting stress, caregiver strain, and their own psychological distress at admission and three, six, and 12 months after discharge. RESULTS The magnitude of reductions in parenting stress between admission and follow-up bore the strongest relationship to improvements in externalizing behavior. The largest and most sustained decreases in externalizing behavior arose among youngsters whose parents reported high parenting stress at admission and low parenting stress after discharge. By contrast, children whose parents reported low parenting stress at admission and follow-up showed significantly less postdischarge improvement. Parenting stress changes were not attributable to changes in behavioral symptoms. Parenting stress eclipsed relationships between behavior management practices and child outcomes, suggesting that parenting stress might have a mediational role. CONCLUSIONS High initial parenting stress disposed to better outcomes over the year of follow-up. Consistently low stress predicted less improvement. Higher stress at admission may imply more advantageous parent-child relationships or motivation for subsequent persistence with treatment. Interventions that ameliorate high stress may warrant further study. Low parenting stress might signify disengagement, or, alternatively, that parents of some chronically impaired children become rather inured to fluctuations in behavioral problems. If confirmed, further examination of these and other accounts for a relationship between low parenting stress and suboptimal child outcome seems warranted.
Strategic Trade Policy Reconsidered: National Rivalry vs Free Trade vs International Cooperation

Sharing the concerns of others about strategic trade policy, the authors nevertheless dispute free trade as the favored option. The 'free' in free trade is seen as freedom at a cost; it refers to strategic decisionmakers in transnational corporations being free to further their own ends despite resistance from others. The authors advocate 'trade strategies,' public policy initiatives aimed at democratizing strategic decisions concerning international trade. Rather than supporting national champions and national rivalry, and unlike earlier strategic trade theory, their arguments favor networks of smaller firms and a process where conflicts are recognized and addressed in a spirit of international cooperation. Copyright 1998 by WWZ and Helbing & Lichtenhahn Verlag AG