Miracle-dz/UniFAR-FTUs huggingface dataset:
Developer Heterogeneity and Formation of Communication Networks in Open Source Software Projects

Over the past few years, open source software (OSS) development has gained a huge popularity and has attracted a large variety of developers. According to software engineering folklore, the architecture and the organization of software depend on the communication patterns of the contributors. Communication patterns among developers influence knowledge sharing among them. Unlike in a formal organization, the communication network structures in an OSS project evolve unrestricted and unplanned. We develop a non-cooperative game-theoretic model to investigate the network formation in an OSS team and to characterize the stable and efficient structures. Developer heterogeneity in the network is incorporated based on their informative value. We find that there may exist several stable structures that are inefficient and there may not always exist a stable structure that is efficient. The tension between the stability and efficiency of structures results from developers acting in their self-interest rather than the group interest. Whenever there is such tension, the stable structure is either underconnected across types or overconnected within type of developers from an efficiency perspective. We further discuss how an administrator can help evolve a stable network into an efficient one. Empirically, we use the latent class model and analyze two real-world OSS projects hosted at SourceForge. For each project, different types of developers and a stable structure are identified, which fits well with the predictions of our model. Overall, our study sheds light on how developer abilities and incentives affect communication network formation in OSS projects.
Customer Profitability Analysis: Measurement, Concentration, and Research Directions

As marketing activities become more precisely targeted to consumers through direct and interactive forms of communication, customer profitability takes on a central role in the development of marketing strategies. This paper provides a conceptual and methodological foundation for measuring customer profitability by generalizing approaches to measuring customer lifetime value in direct marketing for broader target marketing applications. Particular emphasis is placed on the precise specification of the inputs into a profitability analysis and the measures of the degree of concentration of profits among customers. An empirical analysis involving the profitability of customers in a business-to-business marketing context is described, along with research propositions for future work on the determinants of customer profitability.
Evaluation of patients with severe pulmonary disease before and after pulmonary rehabilitation

Purpose: The purpose was to evaluate the impact of inpatient pulmonary rehabilitation program upon changes in anxiety, depression, psychological outlook, and dyspnea. A secondary purpose was to predict changes in psychological outlook, depression, anxiety, and dyspnea by using three pulmonary function tests and age. Methods: The design consisted of an observational study with pre–post comparisons. Forty-five patients with severe pulmonary disease, mean age 67.4 years (SD 9.2), mean FEV1 = 31.44% predicted, 13 men, 32 women were compared on four measures before and after 3 weeks of rehabilitation. Measures were Beck Depression Inventory, Hamilton Anxiety Scale, Goldberg Scale, and Modified Borg Scale. In addition, a linear multiple regression model using age, gender, % predicted FEV1, FEV1/FVC, % predicted DLCO as independent variables were used to predict changes. Results: Patients who completed the pulmonary program showed significant changes in favour of post scores on all four scales at p < 0.001. The program significantly reduced anxiety and depression, and increased positive psychological outlook in severe pulmonary disease. Perceived breathlessness on the Borg Scale was significantly reduced (p < 0.0001). The multiple regression model was not statistically significant for prediction of any of the changes. Conclusions: Patients with severe pulmonary disease can significantly improve their psychological outlook and decrease anxiety and depression when they complete an inpatient pulmonary rehabilitation program. Psychological gains and perception of breathlessness improve with rehabilitation, even though FEV1 and other pulmonary function tests may not predict these changes. A second implication is that rehabilitation improves psychological outlook with both severely ill patients and a group with mixed pulmonary and cardiac disease.
Impact of Oxygen Flow Rate on the Instability Under Positive Bias Stresses in DC-Sputtered Amorphous InGaZnO Thin-Film Transistors

The effect of O2 flow rate (OFR) during channel deposition is investigated on the electrical instability of the amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs) under positive gate bias stresses. From the transfer curves measured before and after bias stresses, we can observe that the high OFR degrades the electrical stability and causes the large threshold voltage shift (ΔVT) in a-IGZO TFTs. To elucidate the origin of the observed phenomenon, we extract and compare the subgap density of states (DOS) in devices with various OFRs. The extracted DOS shows that the subgap states become higher with the increase of OFR in a wide range of bandgap, and the enhanced electron trapping due to the increased number of trap states is considered as the cause of larger ΔVT in higher OFR devices.
Analysing controlled trials with baseline and follow up measurements

In many randomised trials researchers measure a continuous variable at baseline and again as an outcome assessed at follow up. Baseline measurements are common in trials of chronic conditions where researchers want to see whether a treatment can reduce pre-existing levels of pain, anxiety, hypertension, and the like. Statistical comparisons in such trials can be made in several ways. Comparison of follow up (post-treatment) scores will give a result such as “at the end of the trial, mean pain scores were 15 mm (95% confidence interval 10 to 20 mm) lower in the treatment group. ” Alternatively a change score can be calculated by subtracting the follow up score from the baseline score, leading to a statement such as “pain reductions were 20 mm (16 to 24 mm) greater on treatment than control. ” If the average baseline scores are the same in each group the estimated treatment effect will be the same using these two simple approaches. If the treatment is effective the statistical significance of the treatment effect by the two methods will depend on the correlation between baseline and follow up scores. If the correlation is low using the change score will …
Variation of the Transcription Factor 7-Like 2 (TCF7L2) Gene Predicts Impaired Fasting Glucose in Healthy Young Adults

Recently, Grant et al. (1) reported an association between type 2 diabetes and variation in the transcription factor 7-like 2 (TCF7L2) gene. Thereafter, the relation has been replicated in several populations (2–11). The mechanisms by which TCF7L2 variants contribute to the development of type 2 diabetes are incompletely understood. To gain insight on potential mechanisms, we examined the effects of TCF7L2 on the incidence of impaired fasting glucose (IFG) in young adults. The Young Finns Study is a longitudinal study that included 3,596 healthy children and adolescents at baseline in 1980 (12–14). In the present analysis, we used data collected in 1986 and 2001 to assess the effect of the TCF7L2 gene on IFG incidence. Details of methods have been described (15–18). IFG was defined as fasting glucose 5.6–7.0 mmol/l (19,20). Homeostasis model assessment (HOMA) was used to assess β-cell function (HOMA-B) and insulin resistance (HOMA-IR) (21). We genotyped two TCF7L2 single nucleotide polymorphisms (SNPs): 47833C>T (rs7903146) and 98368G>T (rs12255372) (22). These two SNPs were shown to have robust associations with type 2 diabetes and were recommended to be genotyped in attempts at replication (1). Both genotype frequencies were in Hardy-Weinberg equilibrium. Linkage …
Conformational study of [Met5]enkephalin-Arg-Phe in the presence of phosphatidylserine vesicles.

The interaction of [Met5]enkephalin-Arg.Phe with phosphatidylserine (PtdSer) was studied by circular dichroism (CD), two-dimensional nuclear magnetic resonance spectroscopy, hybrid distance geometry simulated annealing (DG-SA) and molecular dynamics (MD) calculations. The very low solubility of [Met5]enkephalin-Arg-Phe and the instability of the solution containing PtdSer vesicles at low pH values did not allow us to observe the amide proton resonances in the usual two-dimensional NMR work. NOESY cross-peaks of protons of side chains from two-dimensional NMR were converted into distances which were used as restraints for modelling with DG-SA and MD. Our results indicate that, in aqueous solutions at pH 7.68 [Met5]enkephalin-Arg-Phe exists in the absence of PtdSer as a random distribution of conformers, whereas in the presence of PtdSer it adopts conformations containing a common orientation of the bonds of C alpha 2, C alpha 3, C alpha 4, and C alpha 5, although different orientations of the peptide planes are consistent with the results. Two of the reported conformers from MD simulations are characterized by the presence of a 2<--4 gamma and inverse gamma turns centered on Gly3. A gradual decline of order was observed when moving from the central moiety of the peptide to both the N-terminus and C-terminus. Finally, the DG-SA and MD calculations resulted in a structure such that the orientation of the Phe4 and Met5 side chains favours hydrophobic interactions with the apolar portion of the PtdSer vesicle to form a hydrophobic cluster. These data support the hypothesis of a role of lipids to modify the conformation of [Met5]enkephalin-Arg-Phe to permit the interactions with the receptor site.
Accounting for Software Development Costs and Information Asymmetry

I investigate the impact of implementing SFAS No. 86, which provides an exception to the GAAP requirement of the immediate expensing of research and development (R&D), on information asymmetry. Using bid‐ask spread and share turnover as proxies for information asymmetry, I find that after the introduction of SFAS No. 86, information asymmetry decreases for software firms relative to that of other high‐tech firms. Within the software industry, I find that information asymmetry is significantly lower for firms that capitalize (capitalizers) than for those who expense (expensers) software development costs. Thus, accounting for software development costs per SFAS No. 86 reduces information asymmetry and, consequently, the cost of capital. As well, investors' uncertainty about the future benefits of software development costs is reduced when firms capitalize these costs.
The temporal relationship between the preovulatory estrogen peak and the optimal mating period in rhesus and bonnet monkeys.

The optimal mating period was determined for rhesus (Macaca mulatta) and bonnet monkeys (Macaca radiata) using the preovulatory estrogen peak as the point of reference. Blood samples were drawn twice daily and total plasma estrogens were determined by rapid radioimmunoassay. The animals were mated before, at or after the estrogen peak. Of the four rhesus monkeys that conceived during the study, two were bred 12.5 h post-estrogen peak. The precise temporal relationship between the estrogen peak and breeding could not be determined for two of the rhesus monkeys; there is, however, good evidence that breeding occurred within 18-24 h post-estrogen peak. Fertile matings in four bonnet monkeys occurred at 8.0 h pre-peak and 7.5, 12.0, and 12.5 h post-peak. The optimal mating period for both macaque species appears to be limited to an approximately 24 h period at and immediately after the estrogen peak. The temporal position of the preovulatory estrogen peak in relation to the fertile period of the menstrual cycle makes it an excellent indicator for use in detecting an impending fertile period. The apparent brevity of the optimal breeding period and its occurrence 24-36 h prior to the reported time of ovulation suggest temporal relationships regarding breeding, ova and sperm transport, gamete viability, and fertilization which were previously unknown.
CONTRIBUTION OF HOSPITALS TO NORTH DAKOTA'S ECONOMY

Community hospital administrators in North Dakota were surveyed to determine the amount and type of expenditures made to North Dakota entities in 1997. Estimates of net revenues retained within the state were also solicited. Forty-two of the 44 community hospitals in the state responded. Economic activity from hospitals in the state was divided into two groups--community hospitals and all hospitals. In-state expenditures for Federal and Native American facilities were generated from survey results. Expenditures and returns (direct impacts) from community hospitals in the state were about $832 million in 1997. When the six military, Veteran, state, and tribal hospitals were included, industry-wide direct impacts increased to $904 million. Input-output analysis was used to estimate the secondary economic effects. In-state spending by community hospitals and all hospitals was estimated to generate an additional $1.5 billion and $1.7 billion in secondary economic activity, respectively. Gross business volume (direct and secondary effects) attributable to community hospitals in 1997 was estimated at $2.4 billion, while all hospitals were estimated to generate $2.6 billion in the state. Community hospitals and associated facilities (i.e., nursing homes, clinics) in the state were estimated to directly employ 14,013 full-time equivalent positions. Secondary employment resulting from the business activity created by community hospitals was estimated at 36,174 full-time equivalent jobs. Direct and secondary employment attributable to community hospitals represented 14.8 percent of total state employment in 1997. Direct and secondary employment by all hospitals in the state was estimated at 15,355 and 39,921 full-time equivalent jobs, respectively. Direct and secondary employment attributable to all hospitals represented 16.3 percent of all state employment. Community hospitals and all hospitals were also responsible for about $43.5 million and $48.9 million in state-collected tax revenues, respectively. Comparisons to previous estimates of the economic importance of hospitals revealed that the economic contribution of all hospitals in the state has increased in real terms (inflation adjusted) since 1991, despite reductions in the number of hospitals and hospital beds. Gross business volume, adjusted for inflation, for all hospitals was $1.7 billion in 1991. Equivalent estimates for all hospitals in 1997 was nearly $2.4 billion. Hospitals accounted for about 8 percent of economy-wide personal income and 7 percent of state retail sales. In addition, direct and secondary employment from all hospitals (not including clinics and nursing homes) accounted for 15.4 percent of North Dakota's employment in 1997. Hospitals in the state generate a substantial amount of economic activity and continue to be an important contributor to the state's economy.
Investment Coordination and Standardization in Electronic Markets

When using electronic marketplaces as a method to exchange goods and services in business-to-business markets, investments are required to integrate this method of buying and selling into the internal systems of the market participants. These investments are typically information technology (IT) investments by buyers and sellers, and additionalinvestment by owners of the electronic market (EM). In our model we include specifications of the relationships within IT investments by buyers and sellers, the relationships between IT investments and EM investment, as well as the impact of increasing standardization of the market. We find that buyer and seller IT investments and EM investment can be coordinated so that a pure strategy Nash equilibrium obtains over a certain range of EM investment, and demonstrate that this continues to be true whether buyers and sellers are independent of the EM, or if subsets of buyers or sellers own the EM. In the latter case buyers or sellers that own the EM have higher IT investments. We also find that increasing standardization of the market increases equilibrium levels of EM investment.
Customer Engagement as a New Perspective in Customer Management

Since 2000, customer management (CM) research has evolved and has had a significant impact on the marketing discipline. In an increasingly networked society where customers can interact easily with other customers and firms through social networks and other new media, the authors propose that customer engagement is an important new development in CM. Customer engagement is considered as a behavioral manifestation toward the brand or firm that goes beyond transactions. The authors propose a conceptual model of the antecedents, impediments, and firm consequences of customer engagement and relate this model to seven articles appearing in the special issue on customer engagement.
Eating breakfast more frequently is cross-sectionally associated with greater physical activity and lower levels of adiposity in overweight Latina and African American girls.

BACKGROUND Eating breakfast is believed to promote a healthy body weight. Yet, few studies have examined the contribution of energy balance-related behavioral factors to this relation in minority youth. OBJECTIVE We assessed the associations between breakfast consumption and dietary intake, physical activity (PA), and adiposity before and after accounting for energy intake and PA in minority girls. DESIGN Cross-sectional data were obtained on body mass index (BMI), percentage body fat (measured by BodPod), dietary intake (measured with 3-d dietary records), and PA (measured with 7-d accelerometry) from 87 Latina and African American girls 8-17 y of age (75% Latina, 80% overweight). Dietary records were used to categorize girls as more frequent breakfast eaters (MF; 2 or 3 of 3 d; n = 57) or less frequent breakfast eaters (LF; 0 or 1 of 3 d; n = 30). Chi-square tests, ANCOVA, and multiple regression analyses were conducted. Mediation was assessed with a Sobel test. RESULTS Compared with the MF group, the LF group spent 30% less time (12.6 min/d) in moderate-to-vigorous-intensity PA (MVPA; P = 0.004) and had a higher percentage body fat (P = 0.029). MVPA accounted for 25% (95% CI: -8.8%, 58.1%; P = 0.139) of the relation between breakfast consumption and percentage body fat. We were unable to show that energy intake or MVPA was a significant mediator of the relation between breakfast consumption and adiposity in this sample. CONCLUSIONS Evidence suggests that among predominantly overweight minority girls, MVPA, but not energy intake, was associated with both breakfast consumption and adiposity; however, a lack of power reduced our ability to detect a significant mediation effect. Other unobserved variables likely contribute to this relation.
Organizational commitment and governance for supply chain success

Purpose – To examine the nature and extent of commitment to supply chain collaboration. Also, to explore the state of supply chain governance structures.Design/methodology/approach – A multi‐method survey and in‐depth interview methodology was employed to gather data. Content analysis was then used to identify the types and extent of managerial support for supply chain initiatives.Findings – Four types of managerial support are needed to achieve the highest levels of supply chain success: top management support, broad‐based functional support, channel support, and infrastructural/governance support. None of the interview companies have put all four types of support in place. Leading‐edge governance relies on cross‐functional/inter‐organizational teams, executive governance councils, customer advisory boards, supplier advisory councils and a modified reporting structure that overseas all value‐added activities from product conceptualization to customer relationship management. Again, none of the interview .
Transcription of the promoter of the rat NF-1 gene depends on the integrity of an Sp1 recognition site

The transcription start site and promoter of the rat gene coding for the transcription factor NF-1 have been identified. The NF-1 promoter was fused to the chloramphenicol acetyltransferase-coding sequence, and the resulting plasmid was transcriptionally active in the HepG2 cell line. Footprinting and gel retardation analysis indicated that the transcription factor Sp1 binds to the NF-1 promoter. Mutants in the Sp1-binding site displayed a strong reduction in transcriptional activity.
Floating with a Load of FX Debt?

Countries with de jure floating exchange rate regimes are often reluctant to allow their currencies to float freely in practice. One reason why countries may wish to limit exchange rate volatility is potential negative balance sheet effects due to currency mismatches on the balance sheets of firms and households. In this paper, we show in a sample of 15 emerging market economies that countries with large foreign exchange (FX) debt in the non-financial private sector tend to react more strongly to exchange rate changes using both FX interventions and monetary policy. Thus, our results support the idea that an important source of 'fear of floating' is balance sheet currency mismatches. This effect is asymmetric; that is, countries stem depreciation but not appreciation pressure. Moreover, FX debt financed through the domestic banking system is more important for fear of floating than FX debt obtained directly from external sources.
Unitary dilation models of Turing machines in quantum mechanics.

A goal of quantum-mechanical models of the computation process is the description of operators that model changes in the information-bearing degrees of freedom. Iteration of the operators should correspond to steps in the computation, and the final state of halting computations should be stable under iteration. The problem is that operators constructed directly from the process description do not have these properties. In general these operators annihilate the halted state. If information-erasing steps are present, there are additional problems. These problems are illustrated in this paper by consideration of operators for two simple one-step processes and two simple Turing machines. In general the operators are not unitary and, if erasing steps are present, they are not even contraction operators. Various methods of extension or dilation to unitary operators are discussed. Here unitary power dilations are considered as a solution to these problems. It is seen that these dilations automatically provide a good solution to the initial- and final-state problems. For processes with erasing steps, recording steps must be included prior to the dilation, but only for the steps that erase information. Hamiltonians for these processes are also discussed. It is noted that {ital H}, described by exp({minus}{ital iH}{Delta})={ital U}{sup {italmore » T}}, where {ital U}{sup {ital T}} is a unitary step operator for the process and {Delta} a time interval, has complexity problems. These problems and those noted above are avoided here by the use of the Feynman approach to constructing Hamiltonians directly from the unitary power dilations of the model operators. It is seen that the Hamiltonians so constructed have some interesting properties. « less