– We investigate the motion of an overdamped Brownian particle in a periodic potential with weak thermal noise and a time-periodic unbiased (i.e. 〈F (t)〉 = 0) external driving force F (t). By introducing appropriate “waiting-periods”, where F (t) vanishes, an arbitrarily strong enhancement of diffusion in a symmetric potential is possible. In asymmetric periodic potentials (ratchets) the net fl...

Developing and promoting self-directed learning, as an one of the goals in higher education is important because it expected from students to reach the high level of individual capabilities, and able to identify their training needs in order to fix it and evaluate their own learning, without being in a special education system. Conclusion: The literature review showed that self-directed learnin...

The DNA polymerases involved in DNA replication achieve high processivity of nucleotide incorporation by forming a complex with processivity factors. A model system for replicative DNA polymerases, the bacteriophage T7 DNA polymerase (gp5), encoded by gene 5, forms a tight, 11 complex with Escherichia coli thioredoxin. By a mechanism that is not fully understood, thioredoxin acts as a processiv...

We study diffusions, variational principles and associated boundary value problems on directed graphs with natural weightings. We associate to certain subgraphs (domains) a pair of sequences, each of which is invariant under the action of the automorphism group of the underlying graph. We prove that these invariants differ by an explicit combinatorial factor given by Stirling numbers of the fir...

Finding the target site and associating in a specific orientation are essential tasks for DNA-binding proteins. In order to make the target search process as efficient as possible, proteins should not only rapidly diffuse to the target site but also dynamically explore multiple local configurations before diffusing away. Protein flipping is an example of this second process that has been observ...

This thesis proposes a weighted DAG (wDAG) similarity algorithm for match-making in e-Business environments. We focus on the metadata representation of buyer and seller agents, as well as a similarity and associated simplicity measure over this information. In order to make the interaction between agents more meaningful and fine-grained, we choose node-labeled, arc-labeled and arc-weighted dire...

background and purpose : there has been no report in which preoperative evaluation of adc for prediction of post therapeutic outcome was presented. the aim of our study was to retrospectively evaluation the use of the apparent diffusion coefficient (adc) for the prediction of malignancy and the outcome of malignant astrocytic tumors. methods: we reviewed mri of 26 male and 14 female patients wi...

<p style='text-indent:20px;'>In this study, we consider a Lotka–Volterra reaction–diffusion–advection model for two competing species under homogeneous Dirichlet boundary conditions, describing hostile environment at the boundary. In particular, deal with case in which one diffuses constant rate, whereas other has rate diffusion directed movement toward better habitat heterogeneous lethal...

epigenetics alterations, especially dna methylation, play a critical role in control of gene expressions. abnormal patterns of methylation are observed in early-stages of many cancers. therefore, methylation analysis is useful in primary detection of tumors. advances knowledge about the functional role of aberrant epigenetic modifications as potential biomarkers for cancer, have attracted consi...