Miracle-dz/UniFAR-FTUs huggingface dataset:
COMKAT: compartment model kinetic analysis tool.

UNLABELLED Compartment models are the basis for most physiologically based quantification of nuclear medicine data. Although some software packages are available for this purpose, many are expensive, run on relatively few types of computers or are of limited capability, and cannot be extended because of the unavailability of source code. Consequently, institutions with modeling expertise often develop software for themselves, which has the disadvantages of lack of standardization and possible replication of effort. Therefore, general-purpose compartment-modeling software distributed with source code would be a welcome resource for the nuclear medicine community. METHODS We formulated a mathematic framework within which compartment models containing unimolecular and bimolecular (receptor saturation) kinetics can be described. We implemented this framework within MATLAB and call the resultant software COMKAT (Compartment Model Kinetic Analysis Tool). RESULTS COMKAT simplifies the process of defining and solving standard blood flow, 18F-FDG, and receptor models as well as models of a user's own design. In particular, COMKAT automatically defines and implements state, analytic sensitivity, and Jacobian equations. Given these, COMKAT can perform simulations in which model outputs are solved for specified parameter values, thereby allowing the user to predict how sensitive data are to these parameters. In addition, COMKAT can be used to estimate values for the parameters by fitting model output to experimental data. COMKAT is equipped with command-line and graphic user interfaces from which the user can access these features. Examples of these applications are presented along with validation and performance summaries. CONCLUSION COMKAT is a useful software tool and is available without cost to researchers, at www.nuclear. uhrad.com/comkat.
Impacts of the End of the Coffee Export Quota System on International-to-Retail Price Transmission

We examine the impact of the end of the coffee export quota system (EQS) on internationalto- retail price transmission in France, Germany and the United States, taking into account the existence of long-run threshold effects and short-run price transmission asymmetries (PTAs). We find evidence of threshold effects in both periods (EQS and post-EQS) in the three countries and the presence of short-run PTAs during the post-EQS period in the three countries, but not during the EQS period. Our results indicate that the threshold values become smaller and the long-run speed of adjustment decreases during the post-EQS period in the three countries. In the short-run, retail prices in the three countries are more responsive to positive than to negative changes in international prices during the post-EQS period, providing evidence of short-run PTAs. However, changes in international prices are passed on to retail prices to a greater extent in the United States than in the two European countries. Nonlinear impulse response analyses indicate that a shock in international prices tends to persist more during the EQS period than in the post-EQS period. This suggests that price transmission increased in the post-EQS period, regardless of the direction of the change in international prices. Our results suggest that accounting for thresholds and asymmetries improves the accuracy of impact assessments of policy changes on price transmission processes.
A MODEL OF DUOPOLY SUGGESTING A THEORY OF ENTRY BARRIERS

This paper analyzes a model of duopoly with fixed costs. Leadership by one "established" firm may yield an outcome in which the second is inactive, but entry prevention is not a prior constraint. We find that two aspects of product differentiation have distinct effects: an absolute advantage in demand for the established firm makes entry harder, but a lower cross-price effect facilitates it. In the basic model we maintain the same quantity after entry. An extension of the model deals with the case where the threat of a predatory output increase after entry is made credible by carrying excess capacity prior to entry.
Evaluation of three methods for estimating the Weibull distribution parameters of Chinese pine (Pinus tabulaeformis )

Weibull distribution was used to fit tree diameter data collected from 86 sample plots located in Chinese pine stand in Beijing. To estimate the Weibull distribution parameters, three methods (namely maximum likelihood estimation method (MLE), method of moment (MOM) and least-squares regression method (LSM)) were compared and evaluated on the basis of the mean square error (MSE) and sample size. For these sample plots, the moment method was superior for estimating the parameters of Weibull distribution for tree diameter distribution.
Effects of spatial frequency on audiovisual integration for communication between human and robot

Combing audiovisual signals across modalities can facilitate human perception when communicate with each other in a noisy environment, but robot can't realize communication with human in a complex environment. Recent studies showed that audiovisual integration effects occurred for low intensity visual inputs, and whether visual spatial frequency can influence audiovisual integration is unclear. In order to investigate this, we design the audiovisual integration experiment used a high frequency auditory stimuli and low intensity visual spatial frequency stimuli. Participants were instructed to maintain central fixation and to make a speeded button response with their right index finger when a stimulus in either sensory modality (unimodal or bimodal) was detected. The results showed that low intensity visual facilitate the audiovisual integration, but there were not different among spatial frequency. These findings provide unique insight into how the brain processes an auditory stimuli and visual signal of different frequencies, and will provide some basic data for communication between human and robot.
Knowledge capability, strategic change, and firm performance: The moderating role of the environment

Purpose – This paper seeks to examine the relationships between knowledge capability, strategic change, and firm performance in the US airline industry from regulation to deregulation.Design/methodology/approach – This is a longitudinal study with a cross‐sectional time series research design. A theoretical model is tested in which knowledge capability exerts a direct effect on strategic change; strategic change then influences firm performance. The environment moderates the relationship between strategic change and firm performance. The sample of the study includes the major US air carriers from 1972 to 1995. Knowledge capability is operationalized as the education level and functional diversity of top management. Strategic change is measured as change in hub concentration, a key variable for the airlines. The data for the present study come from archival sources.Findings – Time series statistics with fixed effects are used to examine the relationships between the variables. The results support the theor.
Taxation and Output Growth: Evidence from African Countries

There is considerable debate over the appropriate role for tax policy in developing economies. In one view, tax hikes reduce deficits and ease budgetary pressures, thereby encouraging long-term growth. An alternative view emphasizes the distortionary effects associated with increased taxation and the positive benefits of a carefully designed tax system. This paper tests these propositions by measuring the impact of government taxation and expenditure on aggregate output growth. A theoretical model is derived which shows that the impact of tax distortions on output growth is usually negative. The theoretical model is tested using a pooled cross-section time-series data set for 31 sub-Saharan African countries during 1965-73 and 1974-82. The regressions imply that the positive benefits of government investment during 1965-73 outweighed the distortionary effects of taxes necessary to finance them. By 1974-82, however, the marginal productivity of government investment had fallen; tax-financed public investment was predicted to have reduced output growth. The empirical results also imply that a revenue neutral shift from the import, corporate, and personal tax to a sales/excise (or consumption) tax will encourage output growth.
E-Delivery Channels and Banking Performance in India: A Pragmatic Approach

Technological innovation not only enable a broader reach for consumer banking and financial services in Indian banking sector, but also enhances its capacity for continued and inclusive growth. E-developments in the arena of ATMs, debit cards, credit cards and mobile banking are changing the way businesses work. While customers get the convenience of 24x7 banking, the bank saves in heavy real estate and manpower costs when compared to establishing a branch. The results are indicative of technology invasion in banks as is obvious from increasing number of ATMs, debit and credit cards. But on the flip side the number of branches of foreign sector banks is still limited in rural and semi-urban areas. ANOVA results highlight that there is a significant difference in the number of branches and private, public and foreign sector banks. ANOVA results for ATMs also highlight that there is a significant difference in the ATMs of private, public and foreign sector banks.
Extending the event-based programming model to support sensor-driven ubiquitous computing applications

We propose an extension to the event-based programming model for sensor-driven ubiquitous computing applications. The extension consists of three abstractions: Multi-Event Handlers, Event Streams and Execution Policies. We believe that these additional abstractions simplify the task of writing applications in this domain. In this position paper we present the extensions and demonstrate our prototype middleware implemented in C.
Understanding cyclic trends in social choices

Motivated by trends in popularity of products, we present a formal model for studying trends in our choice of products in terms of three parameters: (1) their innate utility; (2) individual boredom associated with repeated usage of an item; and (3) social influences associated with the preferences from other people. Different from previous work, in this paper we introduce boredom to explain the cyclic pattern in individual and social choices. We formally model boredom and show that a rational individual would make cyclic choices when considering the boredom factor. Furthermore, we extend the model to social choices by showing that a society that votes for a particular style or product can be viewed as a single individual cycling through different choices. We adopt a natural model of utility an individual derives from using an item, i.e., the utility of an item gets discounted by its repeated use and increases when the item is not used. We address the problem of optimally choosing items for usage, so as to maximize overall user satisfaction over a period of time. First we show that the simple greedy heuristic of always choosing the item with the maximum current composite utility can be arbitrarily worse than the optimal. Second, we prove that even with just a single individual, determining the optimal strategy for choosing items is NP-hard. Third, we show that a simple modification to the greedy algorithm is a provably close approximation to the optimal strategy. Finally, we present an experimental study over real-world data collected from query logs to compare our algorithms.
Low-Dose Methylmercury-Induced Apoptosis and Mitochondrial DNA Mutation in Human Embryonic Neural Progenitor Cells

Methylmercury (MeHg) is a long-lasting organic pollutant primarily found in the aquatic environment. The developing brain is particularly sensitive to MeHg due to reduced proliferation of neural stem cell. Although several mechanisms of MeHg-induced apoptosis have been defined in culture models, it remains unclear whether mitochondrial DNA (mtDNA) mutation is involved in the toxic effect of MeHg, especially in the neural progenitor cells. In the present study, the ReNcell CX cell, a human neural progenitor cells (hNPCs) line, was exposed to nanomolar concentrations of MeHg (≤50 nM). We found that MeHg altered mitochondrial metabolic function and induced apoptosis. In addition, we observed that MeHg induced ROS production in a dose-dependent manner in hNPCs cells, which was associated with significantly increased expressions of ND1, Cytb, and ATP6. To elucidate the mechanism underlying MeHg toxicity on mitochondrial function, we examined the ATP content and mitochondrial membrane potential in MeHg-treated hNPCs. Our study showed that MeHg exposure led to decreased ATP content and reduced mitochondrial membrane potential, which failed to match the expansion in mtDNA copy number, suggesting impaired mtDNA. Collectively, these results demonstrated that MeHg induced toxicity in hNPCs through altering mitochondrial function and inducing oxidative damage to mtDNA.
XRCC1 Polymorphisms and Urinary 8-Hydroxydeoxyguanine Levels Are Associated with Urothelial Carcinoma

The aim of this study was to examine the associations between the combined effects of urinary 8-Hydroxydeoxyguanine (8-OHdG) level and polymorphisms of XRCC1 Arg194Trp and XRCC1 Arg399Gln on the risk of urothelial carcinoma (UC). We conducted a hospital-based case-control study that included 168 cases of UC and 336 age- and gender-matched healthy controls. We used polymerase chain reaction and restriction fragment length polymorphism analyses to examine the genotypes of XRCC1 Arg194Trp and XRCC1 Arg399Gln. We used a competitive in vitro enzyme-linked immunosorbent assay to determine urinary 8-OHdG levels. The XRCC1 399 Gln/Gln genotype and the XRCC1 194 Arg/Arg genotype were positively correlated to UC (OR [95%CI] = 2.27 [1.20–4.27] and 1.59 [1.06–2.36], respectively). Urinary 8-OHdG levels were associated with UC in a dose-dependent manner. Participants with the XRCC1 (Arg399Gln) Gln/Gln genotype or the G-C/A-C haplotype of XRCC1 and a high urinary 8-OHdG level had a significantly higher risk of UC than those with the Arg/Arg + Arg/Gln genotype or the G-T haplotype and a low urinary 8-OHdG level. This is the first study to investigate the combined effect of urinary 8-OHdG level and XRCC1 polymorphisms on UC risk. The findings are especially meaningful for participants with XRCC1 399Gln or XRCC1 Arg194 genotypes and a high urinary 8-OHdG level, since these variables are associated with an increased risk of UC.
Does Dividend Policy Lead the Economy?

We analyze the predictive role of the dividend-payout ratio for future economic activity. The results from both in-sample and out-of-sample forecasting analysis show that the dividend-payout ratio is a significant predictor, both in statistical and economic terms, of future economic activity. This effect is particularly strong at intermediate and long horizons, and is robust across three measures of economic activity. Moreover, the dividend payout ratio outperforms several alternative equity and bond predictors in forecasting the economy. These results are consistent with a simple present-value relation for the log dividend-earnings ratio.
The AMU System in the CoNLL-2014 Shared Task: Grammatical Error Correction by Data-Intensive and Feature-Rich Statistical Machine Translation

Statistical machine translation toolkits like Moses have not been designed with grammatical error correction in mind. In order to achieve competitive results in this area, it is not enough to simply add more data. Optimization procedures need to be customized, task-specific features should be introduced. Only then can the decoder take advantage of relevant data. We demonstrate the validity of the above claims by combining web-scale language models and large-scale error-corrected texts with parameter tuning according to the task metric and correction-specific features. Our system achieves a result of 35.0% F0.5 on the blind CoNLL-2014 test set, ranking on third place. A similar system, equipped with identical models but without tuned parameters and specialized features, stagnates at 25.4%.
Alcohol and Dopamine

Dopamine is a neuromodulator that is used by neurons in several brain regions involved in motivation and reinforcement, most importantly the nucleus accumbens (NAc). Dopamine alters the sensitivity of its target neurons to other neurotransmitters, particularly glutamate. In addition, dopamine can affect the neurotransmitter release by the target neurons. Dopamine-containing neurons in the NAc are activated by motivational stimuli, which encourage a person to perform or repeat a behavior. Even low alcohol doses can increase dopamine release in part of the NAc. This dopamine release may contribute to the rewarding effects of alcohol and may thereby play a role in promoting alcohol consumption. In contrast to other stimuli, alcohol-related stimuli maintain their motivational significance even after repeated alcohol administration, which may contribute to the craving for alcohol observed in alcoholics.
Fear of Floating and Inflation Targeting in Turkey

The objective of this paper is to test empirical validity of Fear of Floating hypothesis for Turkey after the adoption of Inflation Targeting. We start applying methodologies developed by Calvo and Reinhart (2002) and Ball and Reyes (2004, 2008) to check the probabilities of changes in exchange rate and monetary policy instruments before and after inflation targeting regime. We then use a VAR model to estimate exchange rate pass-through and response of monetary policy instruments to exchange rate shocks before and after inflation targeting regime. VAR model helps to understand the impacts of switch in monetary policy regime on exchange rate pass-through and foreign exchange market interventions. The paper concludes that after the adoption of inflation targeting regime, the exchange rate pass-through still matters for the attainment of inflation targets and the monetary policy do not exhibit a fear of floating practices.
Managing Potential and Realized Absorptive Capacity: How Do Organizational Antecedents Matter?

Exploring how organizational antecedents affect potential and realized absorptive capacity, this study identifies differing effects for both components of absorptive capacity. Results indicate that organizational mechanisms associated with coordination capabilities (cross-functional interfaces, participation in decision making, and job rotation) primarily enhance a unit's potential absorptive capacity. Organizational mechanisms associated with socialization capabilities (connectedness and socialization tactics) primarily increase a unit's realized absorptive capacity. Our findings reveal why units may have difficulty managing levels of potential and realized absorptive capacity and vary in their ability to create value from their absorptive capacity.
Electrochemical Gating of Tricarboxylic Acid Cycle in Electricity-Producing Bacterial Cells of Shewanella

Energy-conversion systems mediated by bacterial metabolism have recently attracted much attention, and therefore, demands for tuning of bacterial metabolism are increasing. It is widely recognized that intracellular redox atmosphere which is generally tuned by dissolved oxygen concentration or by appropriate selection of an electron acceptor for respiration is one of the important factors determining the bacterial metabolism. In general, electrochemical approaches are valuable for regulation of redox-active objects. However, the intracellular redox conditions are extremely difficult to control electrochemically because of the presence of insulative phospholipid bilayer membranes. In the present work, the limitation can be overcome by use of the bacterial genus Shewanella , which consists of species that are able to respire via cytochromes abundantly expressed in their outer-membrane with solid-state electron acceptors, including anodes. The electrochemical characterization and the gene expression analysis revealed that the activity of tricarboxylic acid (TCA) cycle in Shewanella cells can be reversibly gated simply by changing the anode potential. Importantly, our present results for Shewanella cells cultured in an electrochemical system under poised potential conditions showed the opposite relationship between the current and electron acceptor energy level, and indicate that this unique behavior originates from deactivation of the TCA cycle in the (over-)oxidative region. Our result obtained in this study is the first demonstration of the electrochemical gating of TCA cycle of living cells. And we believe that our findings will contribute to a deeper understanding of redox-dependent regulation systems in living cells, in which the intracellular redox atmosphere is a critical factor determining the regulation of various metabolic and genetic processes.
Sensing surface PEGylation with microcantilevers

Polymers are often used to modify surface properties to control interfacial processes. Their sensitivity to solvent conditions and ability to undergo conformational transitions makes polymers attractive in tailoring surface properties with specific functionalities leading to applications in diverse areas ranging from tribology to colloidal stability and medicine. A key example is polyethylene glycol (PEG), which is widely used as a protein-resistant coating given its low toxicity and biocompatibility. We report here a microcantilever-based sensor for the in situ characterization of PEG monolayer formation on Au using the “grafting to” approach. Moreover, we demonstrate how microcantilevers can be used to monitor conformational changes in the grafted PEG layer in different solvent conditions. This is supported by atomic force microscope (AFM) images and force–distance curve measurements of the microcantilever chip surface, which show that the grafted PEG undergoes a reversible collapse when switching between good and poor solvent conditions, respectively.
IEEE 802.11e Enhanced Distributed Channel Access (EDCA) Throughput Analysis

The upcoming standard IEEE 802.11e will provide Quality of Service (QoS) support in Wireless Local Area Network (WLAN). The contention based channel access method called Enhanced Distributed Channel Access (EDCA) is considered as the mandatory mode for Medium Access Control (MAC) in IEEE 802.11e. This paper presents an accurate throughput analytical model for EDCA in saturated situation. The analytical model is suitable for both basic access and RTS/CTS access mechanisms. It considers the features in EDCA such as different Arbitration Inter-frame Space (AIFS) and contention window for different Access Category (AC), and virtual collision for different priority queue in the same station; and can be easily extended to other features such as Transmission Opportunity (TXOP), etc. The analytical model is evaluated by extensive simulation results, and it provides deep understanding of the effect by different parameter setting to the throughput.