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We demonstrate that the measurement of 1/fα noise at the single molecule or nano-object limit is remarkably distinct from the macroscopic measurement over a large sample. The single-particle measurements yield a conditional time-dependent spectrum. However, the number of units fluctuating on the time scale of the experiment is increasing in such a way that the macroscopic measurements appear perfectly stationary. The single-particle power spectrum is a conditional spectrum, in the sense that we must make a distinction between idler and nonidler units on the time scale of the experiment. We demonstrate our results based on stochastic and deterministic models, in particular the well-known approach of superimposed Lorentzians, the blinking quantum dot model, and deterministic dynamics generated by a nonlinear mapping. Our results show that the 1/fα spectrum is inherently nonstationary even if the macroscopic measurement completely obscures the underlying time dependence of the phenomena. [ABSTRACT FROM AUTHOR]

The power spectrum of a stationary process may be calculated in terms of the autocorrelation function using the Wiener-Khinchin theorem. We here generalize the Wiener-Khinchin theorem for nonstationary processes and introduce a time-dependent power spectrum 〈Stm(ω)〉 where tm is the measurement time. For processes with an aging autocorrelation function of the form 〈I(t)I(t+τ)〉=tΥϕEA(τ/t), where ϕEA(x) is a nonanalytic function when x is small, we find aging 1/ƒβ noise. Aging 1/ƒβ noise is characterized by five critical exponents. We derive the relations between the scaled autocorrelation function and these exponents. We show that our definition of the time-dependent spectrum retains its interpretation as a density of Fourier modes and discuss the relation to the apparent infrared divergence of 1/ƒβ noise. We illustrate our results for blinking-quantum-dot models, single-file diffusion, and Brownian motion in a logarithmic potential. [ABSTRACT FROM AUTHOR]

Objective: Attention deficit hyperactivity disorder (ADHD) is a common neuropsychological disorder primarily diagnosed in childhood. Early intervention was found to significantly improve developmental outcomes, implicating on the role of early identification of ADHD markers. In the current study, we explored the developmental history of children referred to neurological assessment to identify early ADHD predictors., Methods: A total of 92 children and adolescents (41 females) recruited at a pediatric neurology clinic, with suspected ADHD ( n  = 39) or other neurological difficulties ( n  = 53) such as headaches, seizures, tic disorders, orthostatic hypotension, postischemic stroke, intermittent pain, and vasovagal syncope. Developmental history information was obtained from caregivers, and evaluation for possible ADHD was performed. Developmental details were compared between children with and without current ADHD diagnosis., Results: Word-finding difficulties (WFDs) in preschool age was reported in 30.4% of the sample. Among children diagnosed with ADHD, 43% had WFDs history, compared with only 5% in children without ADHD. Among children with WFDs history, 93% were later diagnosed with ADHD compared with 42% in children without WFDs history. The relationship between WFDs and ADHD was significant (chi-square test [1, N  = 92] = 20.478, p  < 0.0001), and a logistic regression model demonstrated that asides from a family history of ADHD, the strongest predictor for ADHD in school age children was a history of WFDs., Conclusion: Preliminary evidence supports a predictive link between preschool WFDs and later ADHD diagnosis, highlighting the importance of early WFDs clinical attention., Competing Interests: None declared., (Thieme. All rights reserved.)

Structure, composition, and stability of ecological populations are shaped by the inter- and intraspecies interactions within their communities. It remains to be fully understood how the interplay of these interactions with other factors, such as immigration, controls the structure, the diversity, and the long-term stability of ecological systems in the presence of noise and fluctuations. We address this problem using a minimal model of interacting multispecies ecological communities that incorporates competition, immigration, and demographic noise. We find that a complete phase diagram exhibits rich behavior with multiple regimes that go beyond the classical "niche" and "neutral" regimes, extending and modifying the "rare biosphere" or "niche-like" dichotomy. In particular, we observe regimes that cannot be characterized as either niche or neutral where a multimodal species abundance distribution is observed. We characterize the transitions between the different regimes and show how these arise from the underlying kinetics of the species turnover, extinction, and invasion. Our model serves as a minimal null model of noisy competitive ecological systems, against which more complex models that include factors such as mutations and environmental noise can be compared.

Quantifying biochemical reaction rates within complex cellular processes remains a key challenge of systems biology even as high-throughput single-cell data have become available to characterize snapshots of population variability. That is because complex systems with stochastic and non-linear interactions are difficult to analyze when not all components can be observed simultaneously and systems cannot be followed over time. Instead of using descriptive statistical models, we show that incompletely specified mechanistic models can be used to translate qualitative knowledge of interactions into reaction rate functions from covariability data between pairs of components. This promises to turn a globally intractable problem into a sequence of solvable inference problems to quantify complex interaction networks from incomplete snapshots of their stochastic fluctuations., Competing Interests: The authors have declared that no competing interests exist.

Introduction: XSome authors have assessed the link between obesity and colon adenoma risk. Moreover, it has been reported that obesity could increase the risk of proximal adenoma development. Accordingly, obese patients may have a distinctive pattern of adenoma recurrence. AIM: To determine whether metachronous adenoma features differ between obese and non-obese subjects submitted to colonoscopy surveillance., Materials and Methods: We prospectively evaluated all patients over 18 years old that underwent surveillance colonoscopy at our institution between June 2013 and June 2014. Date of prior colonoscopy was registered. A body mass index ≥ 30 was used to define obesity. Analysis looking for variables significantly associated with metachronous adenoma was performed. Metachronous adenoma rate was compared between obese and non-obese subjects, as well as size, location, morphological and histopathological characteristics., Results: Overall, 825 subjects were enrolled. Median time of surveillance colonoscopy was 38.9 months. Obesity was statistically more frequent in those subjects with metachronous adenomas (40% vs 25.71%, p < 0.001). On multivariate analysis, obesity [OR 1.7 (1.01-2.9)] and age [OR 1.02 (1-1.05)] were independently associated with metachronous adenoma presence. Obesity was also significantly associated with a higher risk of right colon adenomas [OR 2.4 (1.76-3.26)] and advanced adenoma [OR 1.99 (1.29-3.06)]. The risk is significantly higher in men and in those with a family history of colorectal cancer/adenoma., Conclusion: Obesity was associated with a higher risk of metachronous adenomas on surveillance colonoscopy. A higher risk of right-sided lesions and advanced adenomas was also found in this population.

The standardization and performance testing of analysis tools is a prerequisite to widespread adoption of genome-wide sequencing, particularly in the clinic. However, performance testing is currently complicated by the paucity of standards and comparison metrics, as well as by the heterogeneity in sequencing platforms, applications and protocols. Here we present the genome comparison and analytic testing (GCAT) platform to facilitate development of performance metrics and comparisons of analysis tools across these metrics. Performance is reported through interactive visualizations of benchmark and performance testing data, with support for data slicing and filtering. The platform is freely accessible at http://www.bioplanet.com/gcat.

The esophageal tuberculosis is the rarest form of this infection in the gastrointestinal tract, corresponding to 0.15% of the cases. This pathology is unusual even in countries with high prevalence of tuberculosis. Its clinical presentation could be easily confused with the one of esophageal carcinoma. The diagnosis is reached by demonstrating in a sample of the mucosa the presence of caseating granulomas or by finding the Mycobacterium tuberculosis in a sample of tissue. In the present case report 73-year-old male with dysphagia, weight loss and fever is presented. At the endoscopy an ulcerated lesion of 5 centimeters in the lower third of the esophagus that compromises 50% of the circumference is observed. In the chest x-ray there are bilateral lung infiltrates confirmed by the CT scan. A baciloscopy is done and the result is positive. At the histological analysis giant cells are found and there is evidence of tuberculous bacillus. The patient develops an intestinal obstruction secondary to chagasic megacolon. He presents a massive hemoptisis and die. The aim of this presentation is to comment a pathology rarely reported in the literature and enhance the importance of considering it according to the clinical context.

On the basis of previous findings suggesting that in human embryonic stem cell-derived cardiomyocytes (hESC-CM) the sarcoplasmic reticulum Ca(2+)-induced release of calcium machinery is either absent or immature, in the present study we tested the hypothesis that hESC-CM contain fully functional 1,4,5-inositol trisphosphate (1,4,5-IP(3))-operated intracellular Ca(2+) ([Ca(2+)](i)) stores that can be mobilized upon appropriate physiological stimuli. To test this hypothesis we investigated the effects of angiotensin-II (AT-II) and endothelin-1 (ET-1), which activate the 1,4,5-IP(3) pathway, on [Ca(2+)](i) transients and contractions in beating clusters of hESC-CM. Our major findings were that in paced hESC-CM both AT-II and ET-1 (10(-9) to 10(-7) M) increased the contraction amplitude and the maximal rates of contraction and relaxation. In addition, AT-II (10(-9) to 10(-7) M) increased the [Ca(2+)](i) transient amplitude. The involvement of 1,4,5-IP(3)-dependent intracellular Ca(2+) release in the inotropic effect of AT-II was supported by the findings that (a) hESC-CM express AT-II, ET-1, and 1,4,5-IP(3) receptors determined by immunofluorescence staining, and (b) the effects of AT-II were blocked by 2 microM 2-aminoethoxyphenyl borate (a 1,4,5-IP(3) receptor blocker) and U73122 (a phospholipase C blocker). In conclusion, these findings demonstrate for the first time that hESC-CM exhibit functional AT-II and ET-1 signaling pathways, as well as 1,4,5-IP(3)-operated releasable Ca(2+) stores.