Sensitivity to Rate of Change in Gains Applied by Redirected Walking

Redirected walking allows for natural locomotion in virtual environments that are larger than a user’s physical environment. The mapping between real and virtual motion is modified by scaling some aspect of motion. As a user traverses the virtual environment these modifications (or gains) must be dynamically adjusted to prevent collision with physical obstacles. A significant body of work has established perceptual thresholds on rates of absolute gain, but the effect of changing gain is little understood. We present the results of a user study on the effects of rate of gain change. A psychophysical experiment was conducted with 21 participants. Each participant completed a series of two-alternative forced choice tasks in which they determined whether their virtual motion differed from their physical motion while experiencing one of three different methods of gain change: sudden gain change, slow gain change and constant gain. Gain thresholds were determined by 3 interleaved 2-up 1-down staircases, one per condition. Our results indicate that slow gain change is significantly harder to detect than sudden gain change

Fenomena Perkembangan Islam Dan Hukum Islam Di Indonesia

Syariat Islam dalam pandangan sebagian masyarakat masih terkesan negatif, padahal syariat Islam dalam konteksnya yang luas dan luwes tampak mencerminkan sisi positif untuk diamalkan, sehingga sampai saat ini masih terjadi pro dan kontra dalam penerapan syariat Islam di Indonesia, yang sekaligus juga masih mempertanyakan apakah syariat Islam di Indonesia sebagai mitos atau fakta? Pro-kontra syariat Islam masa lalu (1945-1959) lebih bersifat politis-ideologis-konstitusionalis, sedangkan pro-kontra pada era 1990-an sampai sekarang lebih bersifat legal formal. Dibalik perdebatan pro-kontra penerapan syariat Islam ini, faktanya telah terjadi proses taqninisasi Hukum islam dan/atau Islamisasi peraturan Perundang-undangan yang sudah berlangsung selama kurang lebih 30 tahun, diantaranta adalah lahirnya UU Nomor 1 tahun 1974 tentang Perkawinan, PP No. 9 tahun 1975 tentang Pelaksanaan UU Nomor 1 tentang Perkawinan, Instruksi Presiden Nomor 1 Tahun 1991 tentang Kompilasi Hukum Islam, kemudian berlanjut dengan UU Nomor 7 tahun 1989 tentang Peradilan Agama dan UU Nomor 21 tahun 2008 tentang Perbankan syariah. Berdasarkan fakta yang bersifat akademik ilmiah berupa taqninisasi Hukum Islam dan/atau Islamisasi peraturan Perundang-undangan tersebut, penerapan syariat Islam bukanlah mitos tetatpi fakta hukum yang sangat fenomenal (red)

Pore translocation of knotted DNA rings

We use an accurate coarse-grained model for DNA and stochastic molecular dynamics simulations to study the pore translocation of 10-kbp–long DNA rings that are knotted. By monitoring various topological and physical observables we find that there is not one, as previously assumed, but rather two qualitatively different modes of knot translocation. For both modes the pore obstruction caused by knot passage has a brief duration and typically occurs at a late translocation stage. Both effects are well in agreement with experiments and can be rationalized with a transparent model based on the concurrent tensioning and sliding of the translocating knotted chains. We also observed that the duration of the pore obstruction event is more controlled by the knot translocation velocity than the knot size. These features should advance the interpretation and design of future experiments aimed at probing the spontaneous knotting of biopolymers

How to fold intricately: using theory and experiments to unravel the properties of knotted proteins.

Over the years, advances in experimental and computational methods have helped us to understand the role of thermodynamic, kinetic and active (chaperone-aided) effects in coordinating the folding steps required to achieving a knotted native state. Here, we review such developments by paying particular attention to the complementarity of experimental and computational studies. Key open issues that could be tackled with either or both approaches are finally pointed out.We acknowledge support from the Italian Ministry of Education, grant PRIN 2010HXAW77

On Classes of Neighborhood Resolving Sets of a Graph

Let G=(V,E) be a simple connected graph. A subset S of V is called a neighbourhood set of G if G=\bigcup_{s\in S}<N[s]>, where N[v] denotes the closed neighbourhood of the vertex v in G. Further for each ordered subset S={s_1,s_2, ...,s_k} of V and a vertex $u\in V$, we associate a vector $\Gamma(u/S)=(d(u,s_1),d(u,s_2), ...,d(u,s_k))$ with respect to S, where d(u,v) denote the distance between u and v in G. A subset S is said to be resolving set of G if $\Gamma(u/S)\neq \Gamma(v/S)$ for all $u,v\in V-S$. A neighbouring set of G which is also a resolving set for G is called a neighbourhood resolving set (nr-set). The purpose of this paper is to introduce various types of nr-sets and compute minimum cardinality of each set, in possible cases, particulary for paths and cycles

How to fold intricately: using theory and experiments to unravel the properties of knotted proteins

Over the years, advances in experimental and computational methods have helped us to understand the role of thermodynamic, kinetic and active (chaperone-aided) effects in coordinating the folding steps required to achieving a knotted native state. Here, we review such developments by paying particular attention to the complementarity of experimental and computational studies. Key open issues that could be tackled with either or both approaches are finally pointed out

Non-Gaussianity Consistency Relation for Multi-field Inflation

While detection of the "local form" bispectrum of primordial perturbations would rule out all single-field inflation models, multi-field models would still be allowed. We show that multi-field models described by the $\delta N$ formalism obey an inequality between $f_{\rm NL}$ and one of the local-form {\it trispectrum} amplitudes, $\tau_{\rm NL}$, such that $\tau_{\rm NL}>\frac12(\frac65f_{\rm NL})^2$ with a possible logarithmic scale dependence, provided that 2-loop terms are small. Detection of a violation of this inequality would rule out most of multi-field models, challenging inflation as a mechanism for generating the primoridal perturbations.Comment: 5 pages. Accepted for publication in Physical Review Letter

Directional translocation resistance of Zika xrRNA

xrRNAs from flaviviruses survive in host cells because of their exceptional dichotomic response to the unfolding action of different enzymes. They can be unwound, and hence copied, by replicases, and yet can resist degradation by exonucleases. How the same stretch of xrRNA can encode such diverse responses is an open question. Here, by using atomistic models and translocation simulations, we uncover an elaborate and directional mechanism for how stress propagates when the two xrRNA ends, 5 \u2032 and 3 \u2032, are driven through a pore. Pulling the 3 \u2032 end, as done by replicases, elicits a progressive unfolding; pulling the 5 \u2032 end, as done by exonucleases, triggers a counterintuitive molecular tightening. Thus, in what appears to be a remarkable instance of intra-molecular tensegrity, the very pulling of the 5 \u2032 end is what boosts resistance to translocation and consequently to degradation. The uncovered mechanistic principle might be co-opted to design molecular meta-materials