Impact of noise on a dynamical system: prediction and uncertainties from a swarm-optimized neural network

In this study, an artificial neural network (ANN) based on particle swarm optimization (PSO) was developed for the time series prediction. The hybrid ANN+PSO algorithm was applied on Mackey--Glass chaotic time series in the short-term $x(t+6)$. The performance prediction was evaluated and compared with another studies available in the literature. Also, we presented properties of the dynamical system via the study of chaotic behaviour obtained from the predicted time series. Next, the hybrid ANN+PSO algorithm was complemented with a Gaussian stochastic procedure (called {\it stochastic} hybrid ANN+PSO) in order to obtain a new estimator of the predictions, which also allowed us to compute uncertainties of predictions for noisy Mackey--Glass chaotic time series. Thus, we studied the impact of noise for several cases with a white noise level ($\sigma_{N}$) from 0.01 to 0.1.Comment: 11 pages, 8 figure

Inhibition of granulomatous inflammation and prophylactic treatment of schistosomiasis with a combination of edelfosine and Praziquantel

This is an open access article distributed under the terms of the Creative Commons Attribution License.[Background]: Schistosomiasis is the third most devastating tropical disease worldwide caused by blood flukes of the genus Schistosoma. This parasitic disease is due to immunologic reactions to Schistosoma eggs trapped in tissues. Egg-released antigens stimulate tissue-destructive inflammatory and granulomatous reactions, involving different immune cell populations, including T cells and granulocytes. Granulomas lead to collagen fibers deposition and fibrosis, resulting in organ damage. Praziquantel (PZQ) is the drug of choice for treating all species of schistosomes. However, PZQ kills only adult Schistosoma worms, not immature stages. The inability of PZQ to abort early infection or prevent re-infection, and the lack of prophylactic effect prompt the need for novel drugs and strategies for the prevention of schistosomiasis. [Methodology/Principal Findings]: Using in vitro and in vivo approaches, we have found that the alkylphospholipid analog edelfosine kills schistosomula, and displays anti-inflammatory activity. The combined treatment of PZQ and edelfosine during a few days before and after cercariae infection in a schistosomiasis mouse model, simulating a prophylactic treatment, led to seven major effects: a) killing of Schistosoma parasites at early and late development stages; b) reduction of hepatomegaly; c) granuloma size reduction; d) down-regulation of Th1, Th2 and Th17 responses at late post-infection times, thus inhibiting granuloma formation; e) upregulation of IL-10 at early post-infection times, thus potentiating anti-inflammatory actions; f) down-regulation of IL-10 at late post-infection times, thus favoring resistance to re-infection; g) reduction in the number of blood granulocytes in late post-infection times as compared to infected untreated animals. [Conclusions/Significance]: Taken together, these data suggest that the combined treatment of PZQ and edelfosine promotes a high decrease in granuloma formation, as well as in the cellular immune response that underlies granuloma development, with changes in the cytokine patterns, and may provide a promising and effective strategy for a prophylactic treatment of schistosomiasis.This work was supported by grants from the Junta de Castilla y León (SA342U13, CSI052A11-2, and CSI221A12-2), Real Federación Española de Fútbol-Sociedad Española de Medicina Tropical y Salud Internacional (RFEF-SEMTSI 2013), Spanish Ministerio de Economía y Competitividad (SAF2011-30518, SAF2014-59716-R, and RD12/0036/0065 from Red Temática de Investigación Cooperativa en Cáncer, Instituto de Salud Carlos III, cofunded by the Fondo Europeo de Desarrollo Regional of the European Union), and European Community’s Seventh Framework Programme FP7-2007-2013 (grant HEALTH-F2-2011-256986, PANACREAS).Peer Reviewe

Prevalence of asthma and other allergic conditions in Colombia 2009-2010: a cross-sectional study

Q3Q2Artículo de investigación1-9BACKGROUND: While it is suggested that the prevalence of asthma in developed countries may have stabilized, this is not clear in currently developing countries. Current available information for both adults and children simultaneously on the burden and impact of allergic conditions in Colombia and in many Latin American countries is limited. The objectives of this study were to estimate the prevalence for asthma, allergic rhinitis (AR), atopic eczema (AE), and atopy in six colombian cities; to quantify costs to the patient and her/his family; and to determine levels of Immunoglobulin E (IgE) in asthmatic and healthy subjects. METHODS: We conducted a cross-sectional, population-based study in six cities during the academic year 2009-2010. We used a school-based design for subjects between 5-17 years old. We carried out a community-based strategy for subjects between 1-4 years old and adults between 18-59 years old. Serum samples for total and antigen-specific (IgE) levels were collected using a population-based, nested, case-control design. RESULTS: We obtained information on 5978 subjects. The largest sample of subjects was collected in Bogotá (2392). The current prevalence of asthma symptoms was 12% (95% CI, 10.5-13.7), with 43% (95% CI, 36.3-49.2) reporting having required an emergency department visit or hospitalization in the past 12 months. Physician diagnosed asthma was 7% (95% CI, 6.1-8.0). The current prevalence of AR symptoms was 32% (95% CI, 29.5-33.9), and of AE symptoms was 14% (95% CI, 12.5-15.3). We collected blood samples from 855 subjects; 60.2% of asthmatics and 40.6% of controls could be classified as atopic. CONCLUSIONS: In Colombia, symptom prevalence for asthma, AR and AE, as well as levels of atopy, are substantial. Specifically for asthma, symptom severity and absence from work or study due to symptoms are important. These primary care sensitive conditions remain an unmet public health burden in developing countries such as Colombia

The Atacama Cosmology Telescope: Extragalactic Point Sources in the Southern Surveys at 150, 220 and 280 GHz observed between 2008-2010

We present a multi-frequency, multi-epoch catalog of extragalactic sources. The catalog is based on 150, 220 and 280 GHz observations carried out in 2008, 2009 and 2010 using the Millimeter Bolometric Array Camera on the Atacama Cosmology Telescope. We also present and release 280 GHz maps from 2008 and 2010. The catalog contains 695 sources, found in a sky area of ${\sim}600$ square degrees. It is obtained by cross-matching sources found in 11 sub-catalogs, one for each season and frequency band. Also include are co-added data from ${\sim}150$ and ${\sim}160$ square degrees using 2 and 3 years of overlapping observations. We divide the sources into two populations, synchrotron and dusty emitters, based on their spectral behavior in the 150-220 GHz frequency range. We find 374 synchrotron sources and 321 dusty source candidates. Cross-matching with catalogs from radio to X-ray results in 264 synchrotron sources (71%) and 89 dusty sources (28%) with counterparts, suggesting that 232 dusty candidates are not in existing catalogs. We study the variability and number counts of each population. In the case of synchrotron sources, we find year-to-year variability up to 60%, with a mean value around 35%. As expected, we find no evidence of dusty source variability. Our number counts generally agree with previous measurements and models, except for dusty sources at 280 GHz where some models overestimate our results. We also characterize the spectral energy distribution of a dusty star-forming galaxy, ACT-S J065207-551605, using our data and higher frequency observations.Comment: 24 pages, 16 figures, for associated data products see https://lambda.gsfc.nasa.gov/product/act/act_prod_table.htm

Genetic Diversity in New Members of the Reticulocyte Binding Protein Family in Thai Plasmodium vivax Isolates

Background Plasmodium vivax merozoites specifically invade reticulocytes. Until recently, two reticulocyte-binding proteins (Pvrbp1 and Pvrbp2) expressed at the apical pole of the P. vivax merozoite were considered to be involved in reticulocyte recognition. The genome sequence recently obtained for the Salvador I (Sal-I) strain of P. vivax revealed additional genes in this family, and in particular Pvrbp2a, Pvrbp2b (Pvrbp2 has been renamed as Pvrbp2c) and two pseudogenes Pvrbp2d and Pvrbp3. It had been previously found that Pvrbp2c is substantially more polymorphic than Pvrbp1. The primary goal of this study was to ascertain the level of polymorphism of these new genes. Methodology/Principal Findings The sequence of the Pvrbp2a, Pvrbp2b, Pvrbp2d and Pvrbp3 genes were obtained by amplification/cloning using DNA purified from four isolates collected from patients that acquired the infection in the four cardinal regions of Thailand (west, north, south and east). An additional seven isolates from western Thailand were analyzed for gene copy number variation. There were significant polymorphisms exhibited by these genes (compared to the reference Sal-I strain) with the ratio of mutations leading to a non-synonymous or synonymous amino acid change close to 3∶1 for Pvrbp2a and Pvrbp2b. Although the degree of polymorphism exhibited by these two genes was higher than that of Pvrbp1, it did not reach the exceptional diversity noted for Pvrbp2c. It was interesting to note that variations in the copy number of Pvrbp2a and Pvrbp2b occurred in some isolates. Conclusions/Significance The evolution of different members of the Pvrbp2 family and their relatively high degree of polymorphism suggests that the proteins encoded by these genes are important for parasite survival and are under immune selection. Our data also shows that there are highly conserved regions in rbp2a and rbp2b, which might provide suitable targets for future vaccine development against the blood stage of P. vivax

Identification of Plasmodium vivax Proteins with Potential Role in Invasion Using Sequence Redundancy Reduction and Profile Hidden Markov Models

BACKGROUND: This study describes a bioinformatics approach designed to identify Plasmodium vivax proteins potentially involved in reticulocyte invasion. Specifically, different protein training sets were built and tuned based on different biological parameters, such as experimental evidence of secretion and/or involvement in invasion-related processes. A profile-based sequence method supported by hidden Markov models (HMMs) was then used to build classifiers to search for biologically-related proteins. The transcriptional profile of the P. vivax intra-erythrocyte developmental cycle was then screened using these classifiers. RESULTS: A bioinformatics methodology for identifying potentially secreted P. vivax proteins was designed using sequence redundancy reduction and probabilistic profiles. This methodology led to identifying a set of 45 proteins that are potentially secreted during the P. vivax intra-erythrocyte development cycle and could be involved in cell invasion. Thirteen of the 45 proteins have already been described as vaccine candidates; there is experimental evidence of protein expression for 7 of the 32 remaining ones, while no previous studies of expression, function or immunology have been carried out for the additional 25. CONCLUSIONS: The results support the idea that probabilistic techniques like profile HMMs improve similarity searches. Also, different adjustments such as sequence redundancy reduction using Pisces or Cd-Hit allowed data clustering based on rational reproducible measurements. This kind of approach for selecting proteins with specific functions is highly important for supporting large-scale analyses that could aid in the identification of genes encoding potential new target antigens for vaccine development and drug design. The present study has led to targeting 32 proteins for further testing regarding their ability to induce protective immune responses against P. vivax malaria

Etapa fetal de la programación. Estrategias para un buen control preconcepcional y prenatal

Fetal programming assumes that pregnancy is the period of greatest susceptibility to acquire changes in the cell nucleus as an adaptive response to the presence of certain morbid processes, which, if maintained over time, will be expressed as pathologies in the child, adolescent or adult such as obesity, dyslipidemia, metabolic syndrome, high blood pressure, ischemic heart disease, metabolic diseases such as type 2 diabetes mellitus, psychiatric diseases such as schizophrenia, anxiety, bipolarity, depression, and other neurological diseases such as autism, epilepsy, Alzheimer, and Parkinson’s disease. The objective was to analyze situations to be considered during the preconception, prenatal and postnatal consultation, in order to have an optimal environment in the first 280 days of the individual’s life. Conclusions: The correct gynecological and obstetric control should be oriented to look for a healthy adult, considering the fetus as a patient. A correct programming of the healthy adult begins in guaranteeing the health of the mother before and during pregnancy, childbirth and the puerperium.La programación fetal supone que el embarazo es el período de mayor susceptibilidad para adquirir cambios en el núcleo celular como respuesta adaptativa a ciertos procesos mórbidos, que de mantenerse en el tiempo, se expresarán como patologías en el niño, adolescente o adulto, como la obesidad, dislipidemia, síndrome metabólico, hipertensión arterial, cardiopatía isquémica, enfermedades metabólicas como la diabetes mellitus tipo 2, enfermedades psiquiátricas como esquizofrenia, ansiedad, bipolaridad, depresión y otras neurológicas como autismo, epilepsia, enfermedad de Alzheimer y enfermedad de Parkinson. El objetivo fue analizar situaciones a considerar durante la consulta preconcepcional, prenatal y posnatal, para tener un ambiente óptimo en los primeros 280 días de vida del individuo. El correcto control ginecológico y obstétrico debe orientarse en buscar un adulto sano considerando al feto como paciente. Una correcta programación del adulto sano empieza en garantizar la salud de la madre antes y durante el embarazo, parto y puerperio

Matching colored points with rectangles

Let S be a point set in the plane such that each of its elements is colored either red or blue. A matching of S with rectangles is any set of pairwise-disjoint axis-aligned closed rectangles such that each rectangle contains exactly two points of S. Such a matching is monochromatic if every rectangle contains points of the same color, and is bichromatic if every rectangle contains points of different colors. We study the following two problems: (1) Find a maximum monochromatic matching of S with rectangles. (2) Find a maximum bichromatic matching of S with rectangles. For each problem we provide a polynomial-time approximation algorithm that constructs a matching with at least 1 / 4 of the number of rectangles of an optimal matching. We show that the first problem is -hard even if either the matching rectangles are restricted to axis-aligned segments or S is in general position, that is, no two points of S share the same x or y coordinate. We further show that the second problem is also -hard, even if S is in general position. These -hardness results follow by showing that deciding the existence of a matching that covers all points is -complete in each case. Additionally, we prove that it is -complete to decide the existence of a matching with rectangles that cover all points in the case where all the points have the same color, solving an open problem of Bereg et al

The alkylphospholipid edelfosine shows activity against Strongyloides venezuelensis and induces apoptosis-like cell death

33 p.-6 fig.-1 tab.Strongyloidiasis is widely distributed in the tropical and subtropical areas. Ivermectin is the drug of choice for the treatment. However, the concerns about relying treatment on a single drug make identification of new molecules a priority. Alkylphospholipid analogues, including edelfosine, are a group of synthetic compounds that have shown activity against some parasites. The objective was to assess the in vitro and in vivo activity of edelfosine, miltefosine, perifosine against Strongyloides venezuelensis. Moreover, apoptosis-like mechanism in larvae after treatment was studied. Edelfosine displayed the highest activity and the best selectivity index (LD50 = 49.6 ± 5.4 μM, SI = 1.1) compared to miltefosine or perifosine. Third stage larvae after culture with edelfosine were not able to develop an infection in mice. Treatment of mice with edelfosine showed reduction of 47% in parasitic females allocated in the gut. Moreover, DNA fragmentation was observed by TUNEL staining in larvae treated with edelfosine. These results suggest that edelfosine could be an effective drug against strongyloidiasis, probably through induction of apoptosis-like cell death.This work has been supported by Proyectos Integrados IBSAL (IBY15/00003; Salamanca, Spain; Spanish Ministerio de Economía y Competitividad (SAF2011-30518, SAF2014-59716-R, and RD12/0036/0065 from Red Temática de Investigación Cooperativa en Cáncer, Instituto de Salud Carlos III-Fondo Europeo de Desarrollo Regional of the European Union), and the European Union’s Seventh Framework Programme FP7-2007-2013 (grant HEALTH-F2-2011-256986, PANACREAS).Peer reviewe