A computationally efficient method for calculating the maximum conductance of disordered networks: Application to 1-dimensional conductors

Random networks of carbon nanotubes and metallic nanowires have shown to be very useful in the production of transparent, conducting films. The electronic transport on the film depends considerably on the network properties, and on the inter-wire coupling. Here we present a simple, computationally efficient method for the calculation of conductance on random nanostructured networks. The method is implemented on metallic nanowire networks, which are described within a single-orbital tight binding Hamiltonian, and the conductance is calculated with the Kubo formula. We show how the network conductance depends on the average number of connections per wire, and on the number of wires connected to the electrodes. We also show the effect of the inter-/intra-wire hopping ratio on the conductance through the network. Furthermore, we argue that this type of calculation is easily extendable to account for the upper conductivity of realistic films spanned by tunneling networks. When compared to experimental measurements, this quantity provides a clear indication of how much room is available for improving the film conductivity.Comment: 7 pages, 5 figure

Influence of remaining coronal thickness and height on biomechanical behavior of endodontically treated teeth: survival rates, load to fracture and finite element analysis

Objective: To evaluate the effect of restorative strategy (fiber post vs cast post and core), coronal height (0 mm vs 2 mm) and thickness (higher than 1 mm vs lower than 1 mm) on survival rate, fracture resistance and stress distribution. Material and Methods: Seventy-two bovine teeth were cleaned and allocated in six groups (n = 12). Twenty-four teeth were sectioned at 13 mm length (no remaining coronal structure) and forty-eight were sectioned at 15 mm (2 mm remaining coronal structure). Half of the forty-eight had remaining coronal thickness lower than 1 mm and the other half had thickness higher than 1 mm. All root canals were prepared at 10 mm (luting length), fiber posts were cemented in thirty-six specimens and cast post and core in other thirty-six. All teeth were restored with metallic crowns. Specimens were submitted to 1.5 million cycles (100 N, 45°, 10 Hz at 2 mm below incisal edge) and evaluated at each 500,000 cycles to detect failures. Specimens that survived were submitted to load to fracture test. Bidimensional (Rhinoceros® 4.0) models were obteined survival data submitted to Kaplan-Meier (α=0.05) analysis and load to fracture values submitted to ANOVA and Tukey tests (α=0.05). Results: Groups without remaining coronal structure showed survival rates lower than other groups (p=0.001). ANOVA showed higher values of load to fracture for groups with coronal thickness higher than 1 mm (p=0.0043). Finite element analysis showed better stress distribution in groups with remaining coronal structure and restored with fiber post. Conclusion: Specimens without remaining coronal structure have lower survival rates. Specimens with remaining structure lower than 1 mm and without coronal structure support the same load to fracture value independently of the restorative strategy

A contribuição das cooperativas de cafeicultores na melhoria do tipo de café

This paper deals with the statistical analysis of data referring to raw coffee processed by cooperatives in the State of São Paulo, Brasil. Six cooperatives were studied, with a total 289 batches of coffee for all of them. For each batch the weighted average of defects was determined, before and after processing. The square roots of the data thus obtained were submitted to the technique of analysis of variance. Significant improvement in coffee type was proved in all cases, with only one exeption. The exception ocurred for the "Cooperativa da Média Sorocabana", where observed improvement was not statistically significant, this being probably due to tre following reasons: a) data of only 7 batches were available; b) the cooperative is new, and had not yet all the equipment needed. Excellent results were obtained, for example, in the "Cooperativa dos Cafeicultores da Alta Morgiana", were a difference significant at the 1% level of probability was observed, with the following means of square roots of defects and standard errors of the mean: Average number of defects before processing = 7.81 ±0.21. Average number of defects after processing = 3.53 ± 0.21. This mans that the average number of defects was lowered from aproximately 61, before processing, to 12, after processing.Êste trabalho estuda estatísticamente dados sôbre café rebeneficiado por cooperativas de cafeicultores do Estado de São Paulo. Seis cooperativas foram estudadas, com um total de 289 partidas de café. Em cada partida se determinou a média ponderada, do número de defeitos, antes e depois do rebeneficiamento. As raízes quadradas dos dados assim obtidos é que foram analisados. Melhoria estatisticamente significativa do tipo do café foi comprovada em tôdas as cooperativas, com uma única exceção, referente à Cooperativa da Média Sorocabana, onde a diminuição do número de defeitos não atingiu o nível de significância. Esta exceção da Cooperativa da Média Sorocabana provàvelmente se deve às seguintes razões: a) Apenas 7 partidas de café foram beneficiadas. b) A Cooperativa, ainda nova, não dispunha ainda de equipamento completo. Resultados excelentes foram obtidos, por exemplo, na Cooperativa dos Cafeicultores da Alta Mogiana, onde a diferênça observada foi significativa ao nível de 1% de probabilidade. As médias foram as seguintes: Média das raízes quadradas dos números de defeitos antes do rebeneficiamento = 7,81 ± 0,21. Média das raízes quadradas dos números de defeitos depois do rebeneficiamento = 3,53 ± 4,21. Estas médias correspondem a 61 defeitos para o café antes do rebeneficiamento, e 12 depois dêle

Proteomic profile of culture filtrate from the Brazilian vaccine strain Mycobacterium bovis BCG Moreau compared to M. bovis BCG Pasteur

<p>Abstract</p> <p>Background</p> <p>Bacille Calmette-Guerin (BCG) is currently the only available vaccine against tuberculosis (TB) and comprises a heterogeneous family of sub-strains with genotypic and phenotypic differences. The World Health Organization (WHO) affirms that the characterization of BCG sub-strains, both on genomic and proteomic levels, is crucial for a better comprehension of the vaccine. In addition, these studies can contribute in the development of a more efficient vaccine against TB. Here, we combine two-dimensional electrophoresis (2DE) and mass spectrometry to analyse the proteomic profile of culture filtrate proteins (CFPs) from <it>M. bovis </it>BCG Moreau, the Brazilian vaccine strain, comparing it to that of BCG Pasteur. CFPs are considered of great importance given their dominant immunogenicity and role in pathogenesis, being available for interaction with host cells since early infection.</p> <p>Results</p> <p>The 2DE proteomic map of <it>M. bovis </it>BCG Moreau CFPs in the pH range 3 - 8 allowed the identification of 158 spots corresponding to 101 different proteins, identified by MS/MS. Comparison to BCG Pasteur highlights the great similarity between these BCG strains. However, quantitative analysis shows a higher expression of immunogenic proteins such as Rv1860 (BCG1896, Apa), Rv1926c (BCG1965c, Mpb63) and Rv1886c (BCG1923c, Ag85B) in BCG Moreau when compared to BCG Pasteur, while some heat shock proteins, such as Rv0440 (BCG0479, GroEL2) and Rv0350 (BCG0389, DnaK), show the opposite pattern.</p> <p>Conclusions</p> <p>Here we report the detailed 2DE profile of CFPs from <it>M. bovis </it>BCG Moreau and its comparison to BCG Pasteur, identifying differences that may provide relevant information on vaccine efficacy. These findings contribute to the detailed characterization of the Brazilian vaccine strain against TB, revealing aspects that may lead to a better understanding of the factors leading to BCG's variable protective efficacy against TB.</p

Computational and Complex Network Modeling for Analysis of Sprinter Athletes’ Performance in Track Field Tests

The article of record as published may be located at https://doi.org/10.3389/fphys.2018.00843Sports and exercise today are popular for both amateurs and athletes. However, we continue to seek the best ways to analyze best athlete performances and develop specific tools that may help scientists and people in general to analyze athletic achievement. Standard statistics and cause-and-effect research, when applied in isolation, typically do not answer most scientific questions. The human body is a complex holistic system exchanging data during activities, as has been shown in the emerging field of network physiology. However, the literature lacks studies regarding sports performance, running, exercise, and more specifically, sprinter athletes analyzed mathematically through complex network modeling. Here, we propose complex models to jointly analyze distinct tests and variables from track sprinter athletes in an untargeted manner. Through complex propositions, we have incorporated mathematical and computational modeling to analyze anthropometric, biomechanics, and physiological interactions in running exercise conditions. Exercise testing associated with complex network and mathematical outputs make it possible to identify which responses may be critical during running. The physiological basis, aerobic, and biomechanics variables together may play a crucial role in performance. Coaches, trainers, and runners can focus on improving specific outputs that together help toward individuals’ goals. Moreover, our type of analysis can inspire the study and analysis of other complex sport scenarios

Detection of rabies virus nucleoprotein-RNA in several organs outside the Central Nervous System in naturally-infected vampire bats

Rabies is a neurological disease, but the rabies virus spread to several organs outside the central nervous system (CNS). The rabies virus antigen or RNA has been identified from the salivary glands, the lungs, the kidneys, the heart and the liver. This work aimed to identify the presence of the rabies virus in non-neuronal organs from naturally-infected vampire bats and to study the rabies virus in the salivary glands of healthy vampire bats. Out of the five bats that were positive for rabies in the CNS, by fluorescent antibody test (FAT), viral isolation in N2A cells and reverse transcription -polymerase chain reaction (RT-PCR), 100% (5/5) were positive for rabies in samples of the tongue and the heart, 80% (4/5) in the kidneys, 40% (2/5) in samples of the salivary glands and the lungs, and 20% (1/5) in the liver by RT-PCR test. All the nine bats that were negative for rabies in the CNS, by FAT, viral isolation and RT-PCR were negative for rabies in the salivary glands by RT-PCR test. Possible consequences for rabies epidemiology and pathogenesis are discussed in this work. INDEX TERMS: Lyssavirus, Desmodus rotundus, non-neuronal organs, rabies. RESUMO.-[Detecção de núcleoproteína-RNA do vírus rábico em diversos órgãos fora do sistema nervoso central de morcegos hematófagos infectados naturalmente.] A raiva é uma doença neurológica, mas o vírus da raiva se dispersa para diversos órgãos fora do sistema nervoso central (SNC). Antígeno ou RNA do vírus da raiva já foram detectados em vários órgãos, tais como glândula salivar, pulmão, rim, coração e fígado. O presente trabalho teve como objetivo identificar a presença do vírus da raiva em órgãos não neuronais de morcegos hematófagos infectados naturalmente, e pesquisar a presença do ví-rus na glândula salivar de morcegos hematófagos sadios. Dos cinco morcegos positivos para a raiva no SNC pelas técnicas de imunofluorescência direta e isolamento viral em células N2A, 100% (5/5) foram positivos para a raiva nas amostras de língua e coração, 80% (4/5) no rim, 40% (2/5) nas amostras de glândula salivar e pulmão, e 20% (4/5) no fígado pela técnica de RT-PCR. Todos os nove morcegos negativos no SNC, pela imunofluorescência e isolamento viral, foram negativos na glândula salivar pela RT-PCR. Possíveis consequências para a epidemiologia e patogênese da raiva são discutidas

Identification of novel soybean microRNAs involved in abiotic and biotic stresses

<p>Abstract</p> <p>Background</p> <p>Small RNAs (19-24 nt) are key regulators of gene expression that guide both transcriptional and post-transcriptional silencing mechanisms in eukaryotes. Current studies have demonstrated that microRNAs (miRNAs) act in several plant pathways associated with tissue proliferation, differentiation, and development and in response to abiotic and biotic stresses. In order to identify new miRNAs in soybean and to verify those that are possibly water deficit and rust-stress regulated, eight libraries of small RNAs were constructed and submitted to Solexa sequencing.</p> <p>Results</p> <p>The libraries were developed from drought-sensitive and tolerant seedlings and rust-susceptible and resistant soybeans with or without stressors. Sequencing the library and subsequent analyses detected 256 miRNAs. From this total, we identified 24 families of novel miRNAs that had not been reported before, six families of conserved miRNAs that exist in other plants species, and 22 families previously reported in soybean. We also observed the presence of several isomiRNAs during our analyses. To validate novel miRNAs, we performed RT-qPCR across the eight different libraries. Among the 11 miRNAs analyzed, all showed different expression profiles during biotic and abiotic stresses to soybean. The majority of miRNAs were up-regulated during water deficit stress in the sensitive plants. However, for the tolerant genotype, most of the miRNAs were down regulated. The pattern of miRNAs expression was also different for the distinct genotypes submitted to the pathogen stress. Most miRNAs were down regulated during the fungus infection in the susceptible genotype; however, in the resistant genotype, most miRNAs did not vary during rust attack. A prediction of the putative targets was carried out for conserved and novel miRNAs families.</p> <p>Conclusions</p> <p>Validation of our results with quantitative RT-qPCR revealed that Solexa sequencing is a powerful tool for miRNA discovery. The identification of differentially expressed plant miRNAs provides molecular evidence for the possible involvement of miRNAs in the process of water deficit- and rust-stress responses.</p