673 research outputs found

    Nonequilibrium design strategies for functional colloidal assemblies

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    We use a nonequilibrium variational principle to optimize the steady-state, shear-induced interconversion of self-assembled nanoclusters of DNA-coated colloids. Employing this principle within a stochastic optimization algorithm allows us to discover design strategies for functional materials. We find that far-from-equilibrium shear flow can significantly enhance the flux between specific colloidal states by decoupling trade-offs between stability and reactivity required by systems in equilibrium. For isolated nanoclusters, we find nonequilibrium strategies for amplifying transition rates by coupling a given reaction coordinate to the background shear flow. We also find that shear flow can be made to selectively break detailed balance and maximize probability currents by modifying the stability of intermediates. For a microphase consisting of many nanoclusters, we study the flux of colloids hopping between clusters. We find that a shear flow can amplify the flux without a proportional compromise on the microphase structure. This approach provides a general means of uncovering design principles for nanoscale, autonomous, functional materials driven far from equilibrium.Comment: 15 pages, 8 figure

    Variational design principles for nonequilibrium colloidal assembly

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    Using large deviation theory and principles of stochastic optimal control, we show that rare molecular dynamics trajectories conditioned on assembling a specific target structure encode a set of interactions and external forces that lead to enhanced stability of that structure. Such a relationship can be formulated into a variational principle, for which we have developed an associated optimization algorithm and have used it to determine optimal forces for targeted self-assembly within nonequilibrium steady-states. We illustrate this perspective on inverse design in a model of colloidal cluster assembly within linear shear flow. We find that colloidal clusters can be assembled with high yield using specific short-range interactions of tunable complexity. Shear decreases the yields of rigid clusters, while small values of shear increase the yields of nonrigid clusters. The enhancement or suppression of the yield due to shear is rationalized with a generalized linear response theory. By studying 21 unique clusters made of 6, 7 or 8 particles, we uncover basic design principles for targeted assembly out of equilibrium.Comment: 13 pages, 8 figure

    COMPARATIVE SEQUENCE ANALYSIS OF TLR2 TLR4 AND TLR9 GENES AMONG SELECTED VERTEBRATES-A META-ANALYSIS

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    Objective: Toll-like receptors are the pattern recognition receptors that recognize a diverse set of conserved pathogens. The receptors are also constantly under selection pressure because of the host antigen modifications. The present study focuses on how selection and mutation have modified the TLRs throughout the evolution in selected groups.Methods: We have selected the sequences of TLR2, 4 and 9 among Hominid group, Homo sapiens, Bubalus bubalis and Danio rerio in our analysis and analyzed different parameters like relative synonymous codon usage (RSCU), sequence divergence, amino acid composition and estimated evolutionary selection forces using Tajima's test.Results: The phylogenetic assessment proved that positive selection influences TLR2 and TLR4, but neutral selection/balancing selection occurred in TLR9 which concluded from the Tajima's test. Synonymous codon usage described the selection of leucine and arginine in all the sequences which describe the structural similarities of TLRs. Values of nucleotide pairs and disparity index proved the close relationship of Hominid and Human between TLR2 and TLR4 and TLR9 where the distant relationship was found with Danio. It can be hypothesized that some of the codons may be best selected for binding with the antigens and it was selected in the genome and some were eliminated due to selection pressure.Conclusion: The present study aimed to substantiate the closeness of TLR2 and TLR4 due to their functional similarity but distant with TLR9 because of the different antigens they recognized in the endosome

    On metric dimension of cube of trees

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    Let G=(V,E)G=(V,E) be a connected graph and dG(u,v)d_{G}(u,v) be the shortest distance between the vertices uu and vv in GG. A set S={s1,s2,⋯ ,sn}⊂V(G)S=\{s_{1},s_{2},\cdots,s_{n}\}\subset V(G) is said to be a {\em resolving set} if for all distinct vertices u,vu,v of GG, there exist an element s∈Ss\in S such that d(s,u)≠d(s,v)d(s,u)\neq d(s,v). The minimum cardinality of a resolving set for a graph GG is called the {\em metric dimension} of GG and it is denoted by β(G)\beta{(G)}. A resolving set having β(G)\beta{(G)} number of vertices is named as {\em metric basis} of GG. The metric dimension problem is to find a metric basis in a graph GG, and it has several real-life applications in network theory, telecommunication, image processing, pattern recognition, and many other fields. In this article, we consider {\em cube of trees} T3=(V,E)T^{3}=(V, E), where any two vertices u,vu,v are adjacent if and only if the distance between them is less than equal to three in TT. We establish the necessary and sufficient conditions of a vertex subset of VV to become a resolving set for T3T^{3}. This helps determine the tight bounds (upper and lower) for the metric dimension of T3T^{3}. Then, for certain well-known cubes of trees, such as caterpillars, lobsters, spiders, and dd-regular trees, we establish the boundaries of the metric dimension. Further, we characterize some restricted families of cube of trees satisfying β(T3)=β(T)\beta{(T^{3})}=\beta{(T)}. We provide a construction showing the existence of a cube of tree attaining every positive integer value as their metric dimension

    Uterus didelphys with obstructed hemivagina with chronic presentation: a case report

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    This is a case report of a 24-year patient who had uterus didelphys with obstructed hemivagina. Clinical manifestations of this case were of progressive dysmenorrhea, abdominal pain after menarche, cyclic difficulty in urination and constipation, with the existing paravaginal tumor indicated this rare anomaly. The diagnosis was by clinical examination and ultrasonography.  The patient underwent successful transvaginal septoplasty and drainage of the hematocolpos and hematometra, which is the appropriate mode of treatment in such cases. 

    CO-BOT: An Intelligent Technique for Designing a Chatbot for Initial COVID-19 Test

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    The coronavirus (nCOV-19), which was discovered, has now spread around the world. However, managing the flow of a large number of cases has proven to be a significant issue for hospitals or healthcare professionals. It is becoming increasingly challenging to speak with a medical expert after the epidemic’s initial wave has passed, particularly in rural areas. Thus, it becomes clear that a Chatbot that is well-designed and implemented can assist patients who are located far away by advocating preventive actions, and viral updates in various cities, and minimising the psychological harm brought on by dread. In this study, a sophisticated Chabot’s design for diagnosing individuals who have been exposed to COVID-19 is presented, along with recommendations for immediate safety measures. Additionally, when symptoms grow serious, this virtual assistant makes contact with specialised medical professionals
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