Exploiting Resolution-based Representations for MaxSAT Solving

Most recent MaxSAT algorithms rely on a succession of calls to a SAT solver in order to find an optimal solution. In particular, several algorithms take advantage of the ability of SAT solvers to identify unsatisfiable subformulas. Usually, these MaxSAT algorithms perform better when small unsatisfiable subformulas are found early. However, this is not the case in many problem instances, since the whole formula is given to the SAT solver in each call. In this paper, we propose to partition the MaxSAT formula using a resolution-based graph representation. Partitions are then iteratively joined by using a proximity measure extracted from the graph representation of the formula. The algorithm ends when only one partition remains and the optimal solution is found. Experimental results show that this new approach further enhances a state of the art MaxSAT solver to optimally solve a larger set of industrial problem instances

Lamellae Stability in Confined Systems with Gravity

The microphase separation of a diblock copolymer melt confined by hard walls and in the presence of a gravitational field is simulated by means of a cell dynamical system model. It is found that the presence of hard walls normal to the gravitational field are key ingredients to the formation of well ordered lamellae in BCP melts. To this effect the currents in the directions normal and parallel to the field are calculated along the interface of a lamellar domain, showing that the formation of lamellae parallel to the hard boundaries and normal to the field correspond to the stable configuration. Also, it is found thet the field increases the interface width.Comment: 4 pages, 2 figures, submitted to Physical Review

Exact Nonequilibrium Work Generating Function for a Small Classical System

We obtain the exact nonequilibrium work generating function (NEWGF), for a small system consisting of a massive Brownian particle connected to internal and external springs. The external work is provided to the system for a finite time interval. The Jarzynski equality (JE), obtained in this case directly from the NEWGF, is shown to be valid for the present model, in an exact way regardless of the rate of external work

Uveíte, Sífilis e SIDA

Os autores apresentam o caso clínico de um homem de 55 anos com antecedentes de sífilis primária na juventude e quatro reinfecções posteriores, a última das quais há dois anos, adequadamente tratada e com remissão do quadro. Observado em consulta externa de Oftalmologia, por olho vermelho, foi-lhe diagnosticada pan-uveíte, com íris de características sifilíticas (roséola sifilítica). Na sua avaliação laboratorial salientaram-se: Venereal Disease Research Laboratory (VDRL) positivo, Fluorescent Treponemal Antibody Absorbed Test (FTA-ABS) positivo, Vírus da Imunodeficiência Humana (VIH-1) positivo. Internado no Serviço de Medicina, foi submetido a punção lombar, tendo a análise do liquor revelado pleocitose, proteinorraquia aumentada, VDRL negativo, Treponema Pallidum Hemagglutination Assay (TPHA) positivo e FTA/ABS positivo, aspectos estes compatíveis com envolvimento sifilítico do SNC. O diagnóstico de neurosífilis assintomática nos doentes duplamente infectados é difícil e complexo, pois fundamenta-se em testes serológicos que não obedecem ao padrão habitual. A terapêutica é controversa, devido à recorrência dos quadros neurológicos após terapêuticas consideradas adequadas, sendo recomendada vigilância apertada destes doentes

Desenvolvimento inicial do umbuzeiro (Spondias tuberosa Arruda) no semi-arido pernambucano.

Visando identificar os efeitos da aplicacao de diferentes doses de fosforo sobre o desenvolvimento inicial do umbuzeiro, o presente trabalho foi instalado no Campo Experimental da Embrapa Sermi-Arido, municipio de Petrolina-PE, entre as coordenadas geograficas de 09ø09' Latitude S e 40ø22' Longitude W. A precipitacao pluviometrica media anual e de 500mm, concentrada no periodo de janeiro a marco. A temperatura media mensal e de 26øC, umidade relativa entre 50 e 70%, insolacao media de 2.800 horas/ano, com evaporacao em torno de 2.000 mm/ano. O solo e do tipo Latossolo vermelho amarelo. O experimento foi disposto em um delineamento de blocos ao acaso, com quatro repeticoes, com o plantio realizado no espacamento 6,0 x 6,0 m. Os tratamentos consistiram de quatro doses de P2 O5 (0, 30, 60, e 90 g/planta), aplicadas por ocasiao do plantio, submetidos a tres situacoes: sem irrigacao, com irrigacao e com irrigacao e adubacao de cobertura, totalizando doze tratamentos. A fonte de P2 O5 foi o superfosfato triplo. Todas as unidades experimentais receberam uma adubacao basica por ocasiao do plantio com 15 g de N e 9 g de K2O, fornecidos na forma de ureia e cloreto de potassio, respectivamente. Uma adubacao de cobertura foi realizada aos 60 dias apos o plantio, utilizando-se 15 g/planta de N, na forma de ureia. A unidade experimental foi composta por uma planta. A avaliacao preliminar aos 12 meses de idade demonstrou um desenvolvimento satisfatorio, nao havendo efeito dos tratamentos sobre a sobrevivencia das plantas, o que ratifica a rusticidade desta especie. O crescimento em altura foi reduzido apenas na ausencia de fosforo com irrigacao e cobertura nitrogenada. Este comportamento, se manteve praticamente estavel ate aos 40 meses de idade, ressaltando que as plantas ate esta idade, cresceram muito pouco (incremento medio de 22cm/ano) evidenciando o crescimento muito lento, caracteristica da especie

Ankyloglossia, Syndactyly and Polydactyly in the Pediatric Patient

Ankyloglossia is a congenital alteration in the development of the tongue characterized by the presence of a short or thick lingual frenulum, which leads to a limitation in its movements. There is an associative inconsistency between ankyloglossia and complications with breastfeeding, speech, swallowing, breathing, and the development of orofacial structures, and it is urgent to make more scientific research in this area. In the presence of polydactyly and syndactyly may be also present ankyloglossia. The purpose of this paper is to present two ankyloglossia cases with finger alterations, without a syndromic disease, and lead the medical team to research this topic and make an improved treatment plan for these cases.info:eu-repo/semantics/publishedVersio

MALDI-TOF ICMS for bacterial classification and identification : how many cells are needed?

The identification of species is fundamental to taxonomy. In microbiology, information about each microorganism (e.g., morphological and molecular descriptions, physiological and biochemical properties, ecological roles, and societal risks or benefits) is the key element in this process. Identifications can been a long process with frequent revisions of the taxonomic schemes. These changes make identifications even more complicated for the non-specialised researchers as each taxonomic group has specialised literature, terminology and characters. Analysis of microbial cells for their identification using Matrix Assisted Laser Desorption Ionisation – Time Of Flight Mass Spectrometry (MALDI-TOF MS) is a modern approach for these studies. MALDI-TOF MS has contributed to increasing scientific knowledge about the microorganisms and is now used as a reliable tool for rapid tests in hospitals and health centres. Taking into account MALDI-TOF MS is a sound technique for microbial classification/identification and authentication, it follows that it can be used for quality control programmes of culture collections. However, it is necessary to employ the correct number of cells per sample in the each analysis, as it is a critical issue that requires to be clarified. The main objective of this work was the establishment of the minimum number of cells of Escherichia coli strain DH5α required for identifications by MALDI-TOF MS. E. coli strain DH5α was grown in liquid Luria Bertani (LB) medium at 37°C with shaking for 20 h. The cells were centrifuged and washed with deionised water and subjected to dilution and counted with a Neubauer chamber. Final aqueous bacterial suspensions containing from ca. 103 up to 109 cells per sample were analysed by MALDI-TOF MS using two different matrices, namely 2,5-dihydroxybenzoic acid (DHB) and α-Cyano-4-hydroxycinnamic acid (CHCA). Spectra obtained were analysed by SARAMIS™ Software and final results indicated that for DHB and CHCA the optimal cell concentrations were 107 and 106 cells per MALDI sample, respectively

On exact time-averages of a massive Poisson particle

In this work we study, under the Stratonovich definition, the problem of the damped oscillatory massive particle subject to a heterogeneous Poisson noise characterised by a rate of events, \lambda (t), and a magnitude, \Phi, following an exponential distribution. We tackle the problem by performing exact time-averages over the noise in a similar way to previous works analysing the problem of the Brownian particle. From this procedure we obtain the long-term equilibrium distributions of position and velocity as well as analytical asymptotic expressions for the injection and dissipation of energy terms. Considerations on the emergence of stochastic resonance in this type of system are also set forth.Comment: 21 pages, 5 figures. To be published in Journal of Statistical Mechanics: Theory and Experimen

Critical scaling in standard biased random walks

The spatial coverage produced by a single discrete-time random walk, with asymmetric jump probability $p\neq 1/2$ and non-uniform steps, moving on an infinite one-dimensional lattice is investigated. Analytical calculations are complemented with Monte Carlo simulations. We show that, for appropriate step sizes, the model displays a critical phenomenon, at $p=p_c$. Its scaling properties as well as the main features of the fragmented coverage occurring in the vicinity of the critical point are shown. In particular, in the limit $p\to p_c$, the distribution of fragment lengths is scale-free, with nontrivial exponents. Moreover, the spatial distribution of cracks (unvisited sites) defines a fractal set over the spanned interval. Thus, from the perspective of the covered territory, a very rich critical phenomenology is revealed in a simple one-dimensional standard model.Comment: 4 pages, 4 figure