Miracle-dz/UniFAR-FTUs huggingface dataset:
Throughput Analysis of a Slotted Frequency-Hop Multiple-Access Network

A link throughput analysis is presented for a slotted frequency-hop multiple-access (FHMA) packet radio network (PRN) operating in the presence of background noise, partial-band noise jamming, and partial-band tone jamming. The PRN consists of an arbitrary number of transceivers arranged in a paired-off topology. Forward error-correction coding is used for packet protection. M-ary FSK modulation is used with hard-decision decoding. Expressions are derived for the link throughput in terms of the channel cutoff rate and capacity. The dependency of the optimal processing gain, code rate, and jamming fraction on the population size, traffic intensity, bit energy to background noise ratio, and bit energy to jammer noise ratio is examined in detail. It is shown that a properly designed (optimized) PRN using random-access FHMA offers a significantly larger heavy-load throughput than a random-access frequency-division multiple-access PRN. >
Relationship of body fat with insulin resistance and cardiometabolic risk factors among normal glucose-tolerant subjects.

BACKGROUND The amount of body fat, rather than the amount of excess weight, determines the health risks of obesity, type 2 diabetes mellitus, and cardiovascular disease. AIMS To look at the association of body fat percentage with cardiometabolic risk factors in subjects with normal glucose tolerance (NGT). SETTINGS AND DESIGN Cross-section study from the Chennai Urban Rural Epidemiology Study. MATERIALS AND METHODS Body fat was measured by Beurer body fat analyzer. Metabolic syndrome (MS) was diagnosed based on modified ATPIII guidelines. STATISTICAL ANALYSIS Student's t test or one-way ANOVA (with Tukey's HSD) was used to compare groups for continuous variables. RESULTS Body mass index, waist circumference, systolic and diastolic blood pressure, HOMA IR, serum cholesterol, and LDL cholesterol increased significantly with increasing tertiles of body fat (P<0.001). There was a linear increase in the percentage of body fat with increase in number of components of MS (no metabolic abnormality: 25 ± 11, one metabolic abnormality: 28 ± 10, two metabolic abnormalities: 33 ± 8, and three and more metabolic abnormalities: 35 ± 7) (P<0.001). Regression models showed significant association of body fat with MS after adjusting for age, gender, insulin resistance, and glycated hemoglobin (Odds ratio: 1.04, 95% confidence interval: 1.04 - 1.08, P<0.001). In linear regression analysis, body fat showed a significant association with insulin resistance after adjusting for age, gender, and glycated hemoglobin (β=0.030, P<0.001). CONCLUSIONS A significant association exists between body fat, MS, and cardiometabolic risk factors even among subjects with NGT.
Performance Hypothesis Testing with the Sharpe and Treynor Measures

Asymptotic distributions of the estimators of the Sharpe and Treynor performance measures are derived. Multivariate performance comparison measures, based on the traditional Sharpe and Treynor measures, are developed with their corresponding asymptotic distributions. The behavior of these new performance measures are evaluated in small samples. For single comparisons, a Sharpe z statistic is well behaved and for multiple comparisons a Sharpe chi-square statistic is reasonably well behaved. The powers of the tests are quite sensitive to the population coefficients of variation. Multivariate test statistics based upon the Treynor measure were not very satisfactory. THIS STUDY DEVELOPS SIGNIFICANCE tests of portfolio performance utilizing the Sharpe and Treynor measures. The approximate bias and asymptotic distributions of the estimators of the traditional Sharpe and Treynor performance measures are derived. Multivariate performance comparison measures based on these traditional measures are proposed for comparing the performance of n portfolios. The approximate bias and asymptotic distributions of the multivariate comparison measures are then derived and test statistics proposed. The behavior and usefulness of the statistics for hypothesis testing are evaluated in small samples with simulation experiments. We find that for single comparisons a z statistic based on Sharpe's measure is well behaved at small sample sizes although its power in detecting typical differences with monthly data is small. The z statistic, based on the Treynor measure, is not well behaved in small samples and also lacks power. For multiple comparisons a chi-square statistic, obtained from the Sharpe measures, is reasonably well behaved at small samples and its power increases as the number of portfolios increases and/or the coefficients of variation decrease. A chi-square statistic derived from the Treynor measure is not so well behaved. Section I of the paper discusses the availability of test statistics for various classes of performance measures. It also discusses the use of the Sharpe and Treynor statistics in light of certain undesirable properties they possess and the section concludes with a brief literature survey. Section II derives the performance measure moments, asymptotic distributions, and proposed test statistics. Section III contains the results and conclusions of the univariate and multivariate simul-ations.
Relationship marketing and the management of corporate image in the bank‐SME relationship

Purpose - This study analyzes the nature of relationships between banks and small and medium-sized enterprises (SMEs) by drawing on the theory of relationship marketing (RM) and the concept of corporate image (CI). More specifically, the main purpose of this study is to investigate the relationship between a bank and its SME customers and to examine how the bank's management of customer relationships influences its CI. Design/methodology/approach - A dyadic approach was adopted in this study. Hence, data were gathered via interviews with three bank managers employed in the same bank. An additional 17 interviews were performed with the case study bank's SME customers. Findings - This study indicates that the bank's image will be dependent on the way the bankers manage the relationships with their SME customers. The ability of bankers to understand and meet the SMEs' specific needs highly influences their relationships, which subsequently affects the image of the bank as perceived by their SME customers. Hence, CI reflects the SMEs' overall perceptions of how well the bank has been able to manage the relationship. Originality/value - Although there is a clear theoretical and practical understanding of the importance of RM strategies within banking and the effect of CI on the performance of banks, few studies have taken into consideration the dynamic link between these two concepts and their effect on bank-SME relationships.
Short changed? The market's reaction to the short sale ban of 2008

L'imposition de restrictions sur les ventes de titres a decouvert a-t-elle une incidence sur les cours? Les auteurs analysent la question dans le contexte d'une experience naturelle entourant la courte periode durant laquelle le Canada et les Etats-Unis ont prohibe ces operations sur les titres financiers en 2008.
Estimating Recommendation and Repurchase Thresholds with a Joint Heterogeneity Response Model

Recommendation and repurchase intentions are the two most important dimensions of customer loyalty. Latent satisfaction thresholds at the individual level, if obtained, can function as an additional valid and effective criterion to satisfaction ratings in determining customer behavior. Hence, customer segmentation based on these thresholds can help firms optimize their resources to improve customer retention. This paper proposes a joint heterogeneity response model to simultaneously calibrate the individual-level recommendation and repurchase thresholds through a joint specification over the heterogeneity. We conduct a simulation study to examine the parameter recovery and model comparison between our proposed model and two competing models. We apply our model to the satisfaction survey data of automotive customers. The results outperform the other three alternative models and show more insight into uplifting customer loyalty using a segmentation scheme based on estimated recommendation and repurchase thresholds. In addition to the heterogeneous distribution of thresholds, our results uncover the effects of customer characteristics on the thresholds.
Comparative international diffusion: Patterns, determinants and policies

Using data derived from a number of stand alone surveys in different countries, this paper explores international differences in the paths of diffusion of new manufacturing technologies. It is observed that diffusion paths are technology specific and that no one country either in Europe or North America can be said to exhibit faster, earlier or more extensive diffusion for all technologies than other countries. Using results in the public domain it is also argued that the main driving forces behind diffusion patterns are those generally classified as epidemic and rank effects. Building upon this, the rationale for policy intervention in the diffusion process is discussed and the effectiveness of different policy instruments considered.
Successful retransplantation after renal allograft loss to polyoma virus interstitial nephritis

Background. Although polyoma virus infection is being increasingly recognized as a cause of renal allograft dysfunction and failure, the risk of polyoma recurrence in a subsequent transplant is unknown. We present the first reported case of successful retransplantation after polyoma virus-induced renal allograft loss. Case report. A 40-year-old Caucasian woman received a cadaveric kidney transplant. Baseline immunosuppression included corticosteroids, mycophenolate mofetil, and tacrolimus. Her post-transplant clinical course was complicated by an early acute rejection episode on posttransplant day (PTD) 6, that warranted treatment with OKT3. A biopsy performed on PTD 154 to evaluate a rise in creatinine revealed polyoma virus interstitial nephritis. Despite reduction in immunosuppression, the renal function progressively worsened and dialysis was initiated by PTD 160, followed by transplant nephrectomy on PTD 184. Four months later, she received a living related kidney from her sister. Immunosuppression was initiated with prednisone, azathioprine, and tacrolimus. She had immediate graft function with a decrease in serum creatinine from 12.8 to 1.1 mg/dl. Three and one-half years after her second renal transplant, her allograft functions well, with a serum creatinine of 1 mg/dl. Both quantitative and qualitative assays of blood and urine (by PCR) remain negative for BK virus, indicating the absence of virus reactivation. Conclusion. Judicious retransplantation should be considered as a therapeutic option in the management of polyoma virus induced graft failure. Previous graft loss secondary to polyoma virus infection is not a contraindication to retransplantation.
Market Reaction to Changes in the S&P Smallcap 600 Index

Firms added to (deleted from) the S&P 600 index experience a significant price increase (decrease) at announcement. Firms that newly enter (exit) the S&P universe experience a larger price increase (decrease) than firms that move between S&P indexes. Trading volumes are higher after the announcement and institutional ownership increases (decreases) following index additions (deletions). However, the price and volume effects are temporary and are fully reversed within 60 days, in contrast to the permanent effects reported for S&P 500 changes. Our results support the temporary price-pressure hypothesis and are similar to results reported for Russell 2000 index changes.
Multi‐Period Asset Lifetimes and Accounting‐Based Equity Valuation: Take Care with Constant‐Growth Terminal Value Models!

The merits of accruals in forecasting cash flows or mitigating the volatility of financials shortly after the valuation date are indisputable. However, the usefulness of accounting in equity valuation is very limited if we step beyond a certain forecasting horizon. In this paper, this limitation is emphasized by shedding new light on the accounting‐based value driver model (VDM), a widely used constant‐growth terminal value tool that uses accounting variables as input. The paper shows that, if the lifetime of a firm's assets is, on average, longer than one period, the VDM works accurately only in an idealized academic environment with an even historical corporate investment activity, a single depreciation method for all assets, and no historical inflation volatility. Artificially adjusting real‐world figures to this steady state is possible in principle, but bloats the valuation model and requires exactly the same information that is used in our cash flow‐driven benchmark model (where no adjustment phase is necessary). Beyond these theoretical shortcomings, the VDM is also prone to being misused in valuation practice due to its reliance on book (rather than economic) rates of return, and to its shortcomings in dealing adequately with the assets with an ex ante indefinite lifetime.
Multiplex PCR assay and simple preparation method for stool specimens detect enterotoxigenic Escherichia coli DNA during course of infection

Infection with enterotoxigenic Escherichia coli (ETEC) is a common cause of diarrhea among travelers and residents of developing countries. ETEC produces either a heat-stable toxin or a heat-labile toxin, or both, encoded by plasmid-borne ST and LT genes, respectively. Diagnosis of infection with this subclass of E. coli can be performed with oligonucleotide hybridization probes; however, the sensitivity and specificity of this method are insufficient. A nonradioactive multiplex PCR assay that provides a sensitive and specific method for detecting the presence of either or both toxin genes has been developed. A simple procedure that removed inhibitors of the PCR while efficiently releasing ETEC DNA from stool specimens for subsequent amplification was used. The results for samples from a human volunteer study of ETEC infection indicated that this method of sample preparation results in greater clinical sensitivity than conventional total nucleic acid extraction and ethanol precipitation. Detection of ETEC by a multiplex PCR assay in stool specimens directly processed with a glass matrix and chaotropic solution had greater sensitivity than culture.
Qualitative Analysis of Optimal Investment Strategies in Log-Normal Markets

We provide a concise study of the qualitative behavior of the optimal investment feedback policies and optimal weights, and of the local (absolute and relative) risk tolerance/risk aversion functions in a log-normal market model. We examine their spatial and temporal monotonicity, and their spatial concavity. We also examine their robustness with respect to the investor's risk tolerance coefficient as well as their dependence on the market parameters. We establish new results and provide short alternative proofs to existing ones.
Reconstructing the unknown volatility function

Using market European option prices, a method for computing a {\em smooth} local volatility function in a 1-factor continuous diffusion model is proposed. Smoothness is introduced to facilitate accurate approximation of the true local volatility function from a finite set of observation data. It is emphasized that accurately approximating the true local volatility function is crucial in hedging even simple European options, and pricing exotic options. A spline functional approach is used: the local volatility function is represented by a spline whose values at chosen knots are determined by solving a constrained nonlinear optimization problem. The optimization formulation is amenable to various option evaluation methods; a partial differential equation implementation is discussed. Using a synthetic European call option example, we illustrate the capability of the proposed method in reconstructing the unknown local volatility function. Accuracy of pricing and hedging is also illustrated. Moreover, it is demonstrated that, using a different constant implied volatility for an option with different strike/maturity can produce erroneous hedge factors. In addition, real market European call option data on the SP stability of the approach is demonstrated.
On robust estimation of threshold autoregressions

We investigate the effects of additive outliers on the least squares (LS) estimation of threshold autoregressive models. The class of generalized-M (GM) estimates for linear time series is modified and applied to non-linear threshold processes. A Monte Carlo experiment is carried out to study the robust properties of these estimates. Their relative forecasting performances are also examined. The results indicate that the GM method is preferable to the LS estimation when the observations are contaminated by additive outliers. A real example is also given to illustrate the proposed method.
Capital structure in repeated oligopolies

This article analyzes the effect of a firm's capital structure on its product market strategy in the context of a model of repeated oligopoly. I show that there exists an upper bound on the firm's debt level in the absence of bankruptcy costs. This bound depends on the number of firms in the industry, the discount rate, the elasticity of demand, and other related factors that affect product market equilibrium in oligopolies. I also show that warrants may decrease equilibrium output in oligopolies and that convertible debt and warrants may be used to raise the upper bound on the debt level in specific cases. I show that the effect of capacity constraints on optimal capital structure is nonmonotonic.
Entrepreneurship education: Alumni perceptions of the role of higher education institutions

This paper is concerned with the retrospective perceptions of alumni towards the general provision of entrepreneurship education in higher education institutions (HEIs). Whilst many HEIs provide some form of enterprise training for their student population, relatively few have considered extending this provision to their alumni community. In addition to exploring retrospective perceptions, the research sought to ascertain the current level of entrepreneurial behaviour and the future entrepreneurial ambitions of alumni, and attempted to determine the demand for post‐qualification entrepreneurship training among HEI alumni. The results are encouraging, in that they demonstrate a keen interest amongst alumni in entrepreneurial activities. The main constraints to setting up in business were perceived to be the generation of a viable idea and the lack of both finance and experience. Respondents believed that HEIs should provide a more practical grounding for graduates, specifically citing financial management and business communications skills as key elements missing from the undergraduate curriculum. There was a consensus that HEIs have an important role to play in providing alumni with both formal post‐qualification training and social support networks to encourage entrepreneurial activity.
Forced Audit Firm Change, Continued Partner‐Client Relationship, and Financial Reporting Quality

SUMMARY: This study extends Blouin et al. ([BGR] 2007) by providing partner‐level evidence regarding the effect of continued auditor‐client relationships on financial reporting quality over a three‐year post‐switch period. Using a sample of forced audit firm changes in China where the identities of leading audit partners are available, we find that, consistent with BGR (2007), clients with greater earnings management activities are more likely to follow their former audit partners to a new audit firm, and aggressive follower clients who are audited by former partners are less likely to report abnormally high earnings management items in the first post‐switch year. Moreover, we find that the financial reporting of aggressive follower clients who continue to be audited by former partners becomes significantly more aggressive in the next two post‐switch years; while aggressive follower clients who are audited by non‐former partners do not exhibit a similar pattern in the three post‐switch years. Our findings.
Efficiency and productivity change in UK banking

Despite substantial structural change and a significant intensification of competition in the UK financial services sector in recent years, the UK banking sector remains relatively under researched. This paper uses a panel data sample covering the main UK banks over the period 1984 to 1995 to investigate relative efficiencies within the sector and to analyse productivity change in UK banking over the sample period. The results provide important insights into the size-efficiency relationship in UK banking and offer a perspective on the evolving structure and competitive environment within which banks are currently operating.
The D1‐D2 region of the large subunit ribosomal DNA as barcode for ciliates

Ciliates are a major evolutionary lineage within the alveolates, which are distributed in nearly all habitats on our planet and are an essential component for ecosystem function, processes and stability. Accurate identification of these unicellular eukaryotes through, for example, microscopy or mating type reactions is reserved to few specialists. To satisfy the demand for a DNA barcode for ciliates, which meets the standard criteria for DNA barcodes defined by the Consortium for the Barcode of Life (CBOL), we here evaluated the D1‐D2 region of the ribosomal DNA large subunit (LSU‐rDNA). Primer universality for the phylum Ciliophora was tested in silico with available database sequences as well as in the laboratory with 73 ciliate species, which represented nine of 12 ciliate classes. Primers tested in this study were successful for all tested classes. To test the ability of the D1‐D2 region to resolve conspecific and congeneric sequence divergence, 63 Paramecium strains were sampled from 24 mating species. The average conspecific D1‐D2 variation was 0.18%, whereas congeneric sequence divergence averaged 4.83%. In pairwise genetic distance analyses, we identified a D1‐D2 sequence divergence of <0.6% as an ideal threshold to discriminate Paramecium species. Using this definition, only 3.8% of all conspecific and 3.9% of all congeneric sequence comparisons had the potential of false assignments. Neighbour‐joining analyses inferred monophyly for all taxa but for two Paramecium octaurelia strains. Here, we present a protocol for easy DNA amplification of single cells and voucher deposition. In conclusion, the presented data pinpoint the D1‐D2 region as an excellent candidate for an official CBOL barcode for ciliated protists.
Epidemic and Endemic Malaria Transmission Related to Fish Farming Ponds in the Amazon Frontier

Fish farming in the Amazon has been stimulated as a solution to increase economic development. However, poorly managed fish ponds have been sometimes associated with the presence of Anopheles spp. and consequently, with malaria transmission. In this study, we analyzed the spatial and temporal dynamics of malaria in the state of Acre (and more closely within a single county) to investigate the potential links between aquaculture and malaria transmission in this region. At the state level, we classified the 22 counties into three malaria endemicity patterns, based on the correlation between notification time series. Furthermore, the study period (2003–2013) was divided into two phases (epidemic and post-epidemic). Higher fish pond construction coincided both spatially and temporally with increased rate of malaria notification. Within one malaria endemic county, we investigated the relationship between the geolocation of malaria cases (2011–2012) and their distance to fish ponds. Entomological surveys carried out in these ponds provided measurements of anopheline abundance that were significantly associated with the abundance of malaria cases within 100 m of the ponds (P < 0.005; r = 0.39). These results taken together suggest that fish farming contributes to the maintenance of high transmission levels of malaria in this region.