Cross recurrence quantification for cover song identification

There is growing evidence that nonlinear time series analysis techniques can be used to successfully characterize, classify, or process signals derived from realworld dynamics even though these are not necessarily deterministic and stationary. In the present study we proceed in this direction by addressing an important problem our modern society is facing, the automatic classification of digital information. In particular, we address the automatic identification of cover songs, i.e. alternative renditions of a previously recorded musical piece. For this purpose we here propose a recurrence quantification analysis measure that allows tracking potentially curved and disrupted traces in cross recurrence plots. We apply this measure to cross recurrence plots constructed from the state space representation of musical descriptor time series extracted from the raw audio signal. We show that our method identifies cover songs with a higher accuracy as compared to previously published techniques. Beyond the particular application proposed here, we discuss how our approach can be useful for the characterization of a variety of signals from different scientific disciplines. We study coupled Rössler dynamics with stochastically modulated mean frequencies as one concrete example to illustrate this point.

Identification of cancer stem cells in Ewing's sarcoma.

Cancer stem cells that display tumor-initiating properties have recently been identified in several distinct types of malignancies, holding promise for more effective therapeutic strategies. However, evidence of such cells in sarcomas, which include some of the most aggressive and therapy-resistant tumors, has not been shown to date. Here, we identify and characterize cancer stem cells in Ewing's sarcoma family tumors (ESFT), a highly aggressive pediatric malignancy believed to be of mesenchymal stem cell (MSC) origin. Using magnetic bead cell separation of primary ESFT, we have isolated a subpopulation of CD133+ tumor cells that display the capacity to initiate and sustain tumor growth through serial transplantation in nonobese diabetic/severe combined immunodeficiency mice, re-establishing at each in vivo passage the parental tumor phenotype and hierarchical cell organization. Consistent with the plasticity of MSCs, in vitro differentiation assays showed that the CD133+ cell population retained the ability to differentiate along adipogenic, osteogenic, and chondrogenic lineages. Quantitative real-time PCR analysis of genes implicated in stem cell maintenance revealed that CD133+ ESFT cells express significantly higher levels of OCT4 and NANOG than their CD133- counterparts. Taken together, our observations provide the first identification of ESFT cancer stem cells and demonstration of their MSC properties, a critical step towards a better biological understanding and rational therapeutic targeting of these tumors.

“IF ONLY I COULD�? ~ “THERE IS ALWAYS A LOOPHOLE"? Hope and hopelessness experienced by the severely depressive and nondepressive

The aim of this research was to structure a conceptual model of hope and hopelessness based on dictionary definitions, and to verify this model on the basis of the experiences of the severely depressive and non-depressive elderly. This research has produced a substantive theory of hope and hopelessness which is based on the experiences of the depressive and non-depressive elderly, and on the concept analysis of hope and hopelessness based on English dictionary definitions. The patients who participated in the research were 65 years old and older men and women (n=22) who had been admitted to a psychiatric hospital because of major depression, and another group: the non-depressive elderly (n=21), who were recruited from the pensioners’ clubs. The data were collected in interviews using the Clinical Assessment Tool, developed by Farran, Salloway and Clark (1990) and Farran, Wilken and Popovich (1992), and it produced 553 pages of written text, which were analysed using the ATLAS/ti programme. ATLAS/ti is a tool for analysing qualitative data and is based on Grounded Theory. The medical and nursing records of the depressive elderly completed source triangulation. The concept analysis of hope and hopelessness was made on the basis of the definitions of English dictionaries (n=103), using semantic analysis and the ATLAS/ti programme. The most important hope-promoting factors were human relations, health and managing in everyday living. Autonomy, self-determination and feeling of security were highly appreciated among the elderly. Hopelessness, on the other hand, was most often associated with the same factors: human relations, health and everyday living. Especially, losses of significant others were experienced as strongly hope-diminishing. Old age had brought freedom from duties concerning others, but now, when you finally had an opportunity to enjoy yourself, you could not accomplish anything; you were clasped in the arms of total inability, depression had come. The most obvious difference in the life course of the depressive and nondepressive elderly was the abundance of traumatic experiences in the childhood and youth of the depressive elderly. The continuous circulation of fearful thoughts was almost touchable, and suicidality was described in connection with these thoughts. You were afraid to be awake and also to go to sleep. Managing day by day was the goal. The research produced the Basic Social Process (BSP) of hope: achieving - maintaining - losing, which expresses a continuous balancing between Being without and Being with. The importance of the object of hope was combined with the amount of hope and disappointment. The process of approaching defined the realisation of hope and the process of withdrawal that of losing. Joy and security versus grief and insecurity defined the Being with and Being without. Two core categories were found. The first one “If only I could�? reflects lack of energy, lack of knowledge, lack of courage and lack of ability. The other one “There is always a loophole�? reflects deliberate tracing of possibilities and the belief in finding solutions, and managing.

Epidémiologie des cancers épithéliaux de la peau [Epidemiology of epithelial skin cancers]

With no less than 15,000 estimated new cases diagnosed per year, non melanomatous carcinomas are the commonest cutaneous cancers in the Swiss population. About 1 in 3 new cancer case is a basal (BCC) or a squamous cell carcinoma (SCC). Incidence rates are steadily increasing, faster for BCC than SCC. Rates are higher for men than women and increase exponentially with age. Systematic population-based registration of non melanomatous skin cancers faces many challenges that few cancer registries can meet. Rates of these cancers in Switzerland are among the highest in Europe. Primary and secondary nationwide prevention campaigns have been carried out for nearly 20 years with a focus on the deadliest cutaneous cancer: melanoma. However, detection of non melanomatous skin cancers benefits from these campaigns since prevention messages and means of early detection are similar for melanomas and other skin cancers.

Electrical neuroimaging of memory discrimination based on single-trial multisensory learning.

Multisensory experiences influence subsequent memory performance and brain responses. Studies have thus far concentrated on semantically congruent pairings, leaving unresolved the influence of stimulus pairing and memory sub-types. Here, we paired images with unique, meaningless sounds during a continuous recognition task to determine if purely episodic, single-trial multisensory experiences can incidentally impact subsequent visual object discrimination. Psychophysics and electrical neuroimaging analyses of visual evoked potentials (VEPs) compared responses to repeated images either paired or not with a meaningless sound during initial encounters. Recognition accuracy was significantly impaired for images initially presented as multisensory pairs and could not be explained in terms of differential attention or transfer of effects from encoding to retrieval. VEP modulations occurred at 100-130ms and 270-310ms and stemmed from topographic differences indicative of network configuration changes within the brain. Distributed source estimations localized the earlier effect to regions of the right posterior temporal gyrus (STG) and the later effect to regions of the middle temporal gyrus (MTG). Responses in these regions were stronger for images previously encountered as multisensory pairs. Only the later effect correlated with performance such that greater MTG activity in response to repeated visual stimuli was linked with greater performance decrements. The present findings suggest that brain networks involved in this discrimination may critically depend on whether multisensory events facilitate or impair later visual memory performance. More generally, the data support models whereby effects of multisensory interactions persist to incidentally affect subsequent behavior as well as visual processing during its initial stages.

Ants and their effects on an insect herbivore community associated with the inflorescences of Byrsonima crassifolia (Linnaeus) H.B.K. (Malpighiaceae)

The effects of ants on the insect community on inflorescences of Byrsonima crassifolia (Malpighiaceae) were tested in an ant exclusion experiment in a cerrado vegetation in southeastern Brazil. Forty-four species of insects (23 families) and nine species of ants (6 genera and 3 subfamilies) were found on the inflorescences of B. crassifolia. The exclusion of ants, primarily Camponotus sericeiventris and Camponotus spp., reduced the treehopper population to 20% of the original abundance. Ant exclusion and time influenced the abundance of chewing (Exclusion, P<0.001; Time, P<0.002), and sucking insects (Exclusion, P<0.02; Time, P<0.01). Twice as many chewing and sucking insects were found on ant-excluded inflorescences as compared to control inflorescences (P<0.001). One and half more sucking insects were found on ant-excluded than on control inflorescences. Only time significantly influenced the richness of chewing and sucking insects associated with B. crassifolia inflorescences. Inflorescences on control branches were significantly less attacked by herbivores than inflorescences on ant-excluded branches (P<0.001). Therefore, these results suggest that the presence of ants alters the structure of insect herbivore community associated with B. crassifolia.

The impact of generic reference pricing interventions in the statin market

The objective of this study was to evaluate the intended and unintended impact on pharmaceutical use and sales of three public financing reforms applied to the prescription of statins: a Spanish generic reference pricing (RP) system for lovastatin and simvastatin, and two competing policies introduced by the Andalusian Public Health Service (APHS) for all statins, first a maximum consumer price (MCP) and then a so called quality prescribing incentive for general practitioners (MCP plus PI).This study is designed as an observational, retrospective, interrupted time series analysis with comparison series (APHS and the rest of Spain) of 46 monthly drug use and sales ratios from January 2001 to October 2004 for each active ingredient in the group of statins.RP has been effective at reducing the volume of sales growth of the off-patent statins, yet its overall impact on sales of all statins has been relatively modest. The quantity and volume of sales impact heavily depends on regulatory RP details such as when the system is introduced, how often it is updated, and how the reference price is calculated.

Noise in Brain Activity Engenders Perception and Influences Discrimination Sensitivity.

Behavioral and brain responses to identical stimuli can vary with experimental and task parameters, including the context of stimulus presentation or attention. More surprisingly, computational models suggest that noise-related random fluctuations in brain responses to stimuli would alone be sufficient to engender perceptual differences between physically identical stimuli. In two experiments combining psychophysics and EEG in healthy humans, we investigated brain mechanisms whereby identical stimuli are (erroneously) perceived as different (higher vs lower in pitch or longer vs shorter in duration) in the absence of any change in the experimental context. Even though, as expected, participants' percepts to identical stimuli varied randomly, a classification algorithm based on a mixture of Gaussians model (GMM) showed that there was sufficient information in single-trial EEG to reliably predict participants' judgments of the stimulus dimension. By contrasting electrical neuroimaging analyses of auditory evoked potentials (AEPs) to the identical stimuli as a function of participants' percepts, we identified the precise timing and neural correlates (strength vs topographic modulations) as well as intracranial sources of these erroneous perceptions. In both experiments, AEP differences first occurred ∼100 ms after stimulus onset and were the result of topographic modulations following from changes in the configuration of active brain networks. Source estimations localized the origin of variations in perceived pitch of identical stimuli within right temporal and left frontal areas and of variations in perceived duration within right temporoparietal areas. We discuss our results in terms of providing neurophysiologic evidence for the contribution of random fluctuations in brain activity to conscious perception.

cAMP-dependent chloride secretion mediates tubule enlargement and cyst formation by cultured mammalian collecting duct cells.

Polycystic kidney diseases result from disruption of the genetically defined program that controls the size and geometry of renal tubules. Cysts which frequently arise from the collecting duct (CD) result from cell proliferation and fluid secretion. From mCCD(cl1) cells, a differentiated mouse CD cell line, we isolated a clonal subpopulation (mCCD-N21) that retains morphogenetic capacity. When grown in three-dimensional gels, mCCD-N21 cells formed highly organized tubular structures consisting of a palisade of polarized epithelial cells surrounding a cylindrical lumen. Subsequent addition of cAMP-elevating agents (forskolin or cholera toxin) or of membrane-permeable cAMP analogs (CPT-cAMP) resulted in rapid and progressive dilatation of existing tubules, leading to the formation of cystlike structures. When grown on filters, mCCD-N21 cells exhibited a high transepithelial resistance as well as aldosterone- and/or vasopressin-induced amiloride-sensitive and -insensitive current. The latter was in part inhibited by Na(+)-K(+)-2Cl(-) cotransporter (bumetanide) and chloride channel (NPPB) inhibitors. Real-time PCR analysis confirmed the expression of NKCC1, the ubiquitous Na(+)-K(+)-2Cl(-) cotransporter and cystic fibrosis transmembrane regulator (CFTR) in mCCD-N21 cells. Tubule enlargement and cyst formation were prevented by inhibitors of Na(+)-K(+)-2Cl(-) cotransporters (bumetanide or ethacrynic acid) or CFTR (NPPB or CFTR inhibitor-172). These results further support the notion that cAMP signaling plays a key role in renal cyst formation, at least in part by promoting chloride-driven fluid secretion. This new in vitro model of tubule-to-cyst conversion affords a unique opportunity for investigating the molecular mechanisms that govern the architecture of epithelial tubes, as well as for dissecting the pathophysiological processes underlying cystic kidney diseases.

Comparative morphology of the spermathecae of some species of Chrysomya Robineau-Desvoidy and Cochliomyia Townsend (Diptera, Calliphoridae)

Comparative morphology of the spermathecae of some species of Chrysomya Robineau-Desvoidy and Cochliomyia Townsend (Diptera, Calliphoridae). Little is known about the morphology of the chitinized structures of the spermathecae of the Calliphoridae. In this work, the spermathecae of Chrysomya albiceps Wiedemann, 1819, C. megacephala Fabricius, 1794, Cochliomyia macellaria Fabricius, 1775 and C. hominivorax Coquerel, 1858 are described and illustrated. The occurrence in one species of four spermathecae, an atypical form for blow flies, was recorded for the first time. The analysis of these structures will allow a better understanding of this group as well as provide taxonomic characters for future phylogenetic studies.