On the Impact of Piracy on Innovation in the Presence of Technological and Market Uncertainty

This paper analyses the effect of piracy on innovation in the presence of R&D competition with technological and market uncertainty. With a single innovating firm facing technological uncertainty, piracy unambiguously retards innovation. However, with R&D competition where firms face market and technological uncertainties, we show that piracy may enhance overall innovation. We also show that if the difference between the probabilities of success of the innovating firms is relatively large then piracy enhances the R&D investment and profit of the less efficient firm.Innovation, market uncertainty, R&D race, technological uncertainty

clues: An R Package for Nonparametric Clustering Based on Local Shrinking

Determining the optimal number of clusters appears to be a persistent and controversial issue in cluster analysis. Most existing R packages targeting clustering require the user to specify the number of clusters in advance. However, if this subjectively chosen number is far from optimal, clustering may produce seriously misleading results. In order to address this vexing problem, we develop the R package clues to automate and evaluate the selection of an optimal number of clusters, which is widely applicable in the field of clustering analysis. Package clues uses two main procedures, shrinking and partitioning, to estimate an optimal number of clusters by maximizing an index function, either the CH index or the Silhouette index, rather than relying on guessing a pre-specified number. Five agreement indices (Rand index, Hubert and ArabieâÂÂs adjusted Rand index, Morey and AgrestiâÂÂs adjusted Rand index, Fowlkes and Mallows index and Jaccard index), which measure the degree of agreement between any two partitions, are also provided in clues. In addition to numerical evidence, clues also supplies a deeper insight into the partitioning process with trajectory plots.

Qiu Lin v. Atty Gen USA

Agenc

Uniqueness theorems for entire functions concerning fixed points

AbstractThis paper is devoted to studying the uniqueness problem of entire functions sharing one value or fixed points. We improve some results given by Fang and extend some results given by Fang and Qiu and by Lin and Yi

SYM on Quotients of Spheres and Complex Projective Spaces

We introduce a generic procedure to reduce a supersymmetric Yang-Mills (SYM) theory along the Hopf fiber of squashed $S^{2r-1}$ with $U(1)^r$ isometry, down to the $\mathbb{CP}^{r-1}$ base. This amounts to fixing a Killing vector $v$ generating a $U(1)\subset U(1)^r$ rotation and dimensionally reducing either along $v$ or along another direction contained in $U(1)^r$. To perform such reduction we introduce a $\mathbb{Z}_p$ quotient freely acting along one of the two fibers. For fixed $p$ the resulting manifolds $S^{2r-1}/\mathbb{Z}_p\equiv L^{2r-1}(p,\pm 1)$ are a higher dimensional generalization of lens spaces. In the large $p$ limit the fiber shrinks and effectively we find theories living on the base manifold. Starting from $\mathcal{N}=2$ SYM on $S^3$ and $\mathcal{N}=1$ SYM on $S^5$ we compute the partition functions on $L^{2r-1}(p,\pm 1)$ and, in the large $p$ limit, on $\mathbb{CP}^{r-1}$, respectively for $r=2$ and $r=3$. We show how the reductions along the two inequivalent fibers give rise to two distinct theories on the base. Reducing along $v$ gives an equivariant version of Donaldson-Witten theory while the other choice leads to a supersymmetric theory closely related to Pestun's theory on $S^4$. We use our technique to reproduce known results for $r=2$ and we provide new results for $r=3$. In particular we show how, at large $p$, the sum over fluxes on $\mathbb{CP}^2$ arises from a sum over flat connections on $L^{5}(p,\pm 1)$. Finally, for $r=3$, we also comment on the factorization of perturbative partition functions on non simply connected manifolds.Comment: 36 pages, 2 figure

“Double-Trouble” for Respiratory Control in Pompe Disease

A commentary on ‘Hypoglossal neuropathology and respiratory activity in Pompe mice’, by Lee, K.-Z., Qiu, K., Sandhu, M. S., Elmullah, M. K., Falk, D. J., Lane, M. A., Reier, P. J., Byrne, B. J., and Fuller, D. D. (2011). Front. Physiol. 2:31. doi: 10.3389/fphys.2011.00031

Effects of conservation tillage on organic carbon, nitrogen and enzyme activities in a hydragric anthrosol of Chongqing, China

AbstractPurple paddy (Hydragric Anthrosol in FAO soil classification) is one of important soil resources in Chongqing, China. Long-term conservation tillage may alter distribution of soil organic carbon, nitrogen, and enzyme activities. The objectives of this study were to investigate the impacts of different tillage systems (conventional tillage with rotation of rice and winter fallow (CT-r) system, no-till and ridge culture with rotation of rice and winter fallow (NT-r) system, no-till and ridge culture with rotation of rice and rape (NT-rr) system and conventional tillage with rotation of rice and rape (CT-rr) system) on the depth distribution of soil total organic carbon, nitrogen and enzyme activities (catalase, intverase, and urease activity) in a purple paddy soil after 18 years. Soil total organic carbon and labile organic carbon were significant increased in surface soil layer (0-10cm) under CT-r, NT-r, and NT-rr systems compared to that under CT-rr system. It indicated that conservation tillage practices can sequester soil organic carbon and reduced CO2/CH4 emission. Soil total nitrogen also significant increased in surface soil layer (0-10cm) under CT-r, NT-r, and NT-rr systems with the greatest under CT-r system (36%), followed by under NT-rr system (34%), and the least under NT-r system (20%) compared to CT-rr system. No-till, ridge culture, and rotation of rice and winter fallow were increased soil catalase and urease activities, but the greatest was not observed under NT-r system, under which the catalase activities was significant decreased. Soil invertase activities were significant increased under CT-r system compared to CT-rr systems and only a little increased in 0-20cm soil layer under NT-rr system. Conservation tillage could construct good soil biochemistry environment and maintain soil fertility, and promote agroecosystem sustainable development

Automatic wheeze detection based on auditory modelling

Automatic wheeze detection has several potential benefits compared with reliance on human auscultation: it is experience independent, an automated historical record can easily be kept, and it allows quantification of wheeze severity. Previous attempts to detect wheezes automatically have had partial success but have not been reliable enough to become widely accepted as a useful tool. In this paper an improved algorithm for automatic wheeze detection based on auditory modelling is developed, called the frequency- and duration-dependent threshold algorithm. The mean frequency and duration of each wheeze component are obtained automatically. The detected wheezes are marked on a spectrogram. In the new algorithm, the concept of a frequency- and duration-dependent threshold for wheeze detection is introduced. Another departure from previous work is that the threshold is based not on global power but on power corresponding to a particular frequency range. The algorithm has been tested on 36 subjects, 11 of whom exhibited characteristics of wheeze. The results show a marked improvement in the accuracy of wheeze detection when compared with previous algorithms

Ribosome recycling induces optimal translation rate at low ribosomal availability

Funding statement The authors thank BBSRC (BB/F00513/X1, BB/I020926/1 and DTG) and SULSA for funding. Acknowledgement The authors thank R. Allen, L. Ciandrini, B. Gorgoni and P. Greulich for very helpful discussions and careful reading of the manuscript.Peer reviewedPublisher PD