Relating time complexity of protein folding simulation to approximations of folding time

Finkelstein and Badretdinov [A.V. Finkelstein, A.Y. Badretdinov, Rate of protein folding near the point of thermodynamic equilibrium between the coil and the most stable chain fold, Fold. Des. 2 (1997) 115-121] approximated the folding time of protein sequences of length n by exp(λ⋅n2/3±χ⋅n1/2/2)ns, where λ and χ are constants close to unity. Recently, Fu and Wang [B. Fu, W. Wang, A ²O(n1−1/d⋅logn) time algorithm for d-dimensional protein folding in the HP-model, in: J. Daz, J. Karhumäki, A. Lepistö, D. Sannella (Eds.), Proceedings of the 31st International Colloquium on Automata, Languages and Programming, in: Lecture Notes in Comput. Sci., vol. 3142, Springer-Verlag, Heidelberg, 2004, pp. 630-644] published an exp(O(n1−1/d)⋅lnn) algorithm for d-dimensional protein folding simulation in the HP-model, which is close to the folding time approximation by Finkelstein and Badretdinov and can be seen as a justification of the HP-model for investigating general complexity issues of protein folding. We propose a stochastic local search procedure that is based on logarithmic simulated annealing. We obtain that after (m/δ)^a⋅D Markov chain transitions the probability to be in a minimum energy conformation is at least 1−δ, where m?b(d)⋅n is the maximum neighbourhood size (b(d) small integer), a is a small constant, and D is the maximum value of the minimum escape height from local minima of the underlying energy landscape. We note that the time bound is instance-specific, and we conjecture D<n1−1/d as a worst case upper bound. We analyse experimentally on selected benchmark problems for the d=2 case.     

Isolation and characterisation of lytic bacteriophages against Pseudomonas spp., a novel biological intervention for preventing spoilage of raw milk

Thirteen novel lytic bacteriophages against 13 Pseudomonas strains were isolated from local sewage and initially identified by morphology using a transmission electron microscope. PP1 and PP5 were identified as Pedoviridae and Cystoviridae, respectively; while the other 11 phages were identified as Leviviridae. Most phages showed high infectivity at either 4 °C or 25 °C, and the optimum pH range for phage infectivity was pH 5–7. A strong antimicrobial effect of the phage cocktail was evidenced by a 2-log reduction in Pseudomonas cell number of UHT milk inoculated with Pseudomonas, and a 1-log reduction in the psychrotrophic bacteria and total bacteria counts of raw milk at 4 °C over 5 d. A similar result was obtained at 25 °C over 8 h. Results indicated that the 13 phages with different morphological and physiological characteristics may have a potential application as biological preservative agent in raw milk.     

Development of an immobilization system for in situ micronutrients release

An immobilization system constituted by coated microcapsules was developed aiming at immobilizing probiotic bacteria capable of producing folate and release it in a sustained manner into the intestine. Despite no probiotic folate-producers have been immobilized so far, the system has been developed with this goal and this work reports its stability and ability to release folate under gastro-intestinal conditions.Microcapsules were made of alginate with three consecutive coatings of poly-l-lysine, sodium alginate and chitosan. Turbidity experiments showed a strong electrostatic interaction between these polymers. Fourier transform infrared spectroscopy (FTIR) and confocal analysis showed the stability of the coating materials when applied on the microcapsules, even after they were immersed in solutions simulating conditions in the stomach and small intestine (i.e. pH 2, 60 min and pH 7.2, 120 min, respectively). Coated microcapsules have an average diameter size ranged from 20 and 40 μm, and swelled upon exposure to a neutral medium, without dissolution as showed by microscopy analyses. Release experiments proved the ability of the coated microcapsules to release folic acid, at different rates, depending on the applied coating. Release experiments showed that the first coating (Ɛ-PLL) is characterized by Fickian diffusion as the main release mechanism of folic acid. Fickian rate constant (k_F) decreased with the number of consequent coatings, reflecting the decrease of predominance of Fick's behavior. Results showed that the developed coated microcapsules have suitable characteristics for encapsulation of folic acid aiming in situ release in the intestine.     

Synergy of fiber length and content on free vibration and damping behavior of natural fiber reinforced polyester composite beams

This work addresses the results of experimental investigation carried out on free vibration characteristics of short sisal fiber (SFPC) and short banana fiber (BFPC) polyester composites. Influence of fiber length and weight percentage on mechanical properties and free vibration characteristics are analyzed. Composite beam specimen is fabricated with random fiber orientations at17 MPa compression using compression molding machine. Natural frequencies and associated modal damping values of the composite laminates were obtained by carrying out the experimental modal analysis. It is found that an increase in fiber content increases the mechanical and damping properties. For SFPC, 3 mm fiber length and 50 wt% fiber content yielded better properties, whereas for BFPC, 4 mm fiber length and 50 wt% fiber content was the best combination. Scanning electron microscopy was performed to study the interfacial mechanism.     

Enclothed cognition and hidden meanings in important Ottoman textiles

This paper illustrates how hidden details in garment design may reveal important clues about the motives of the wearer or designer that are of considerable cultural relevance. We suggest these hidden design features may reflect key psychological factors previously not considered. We illustrate this by doing a multilevel analysis of two important sixteenth century examples of Ottoman court clothing from the Topkapi Palace Museum. We show that these garments contain early examples of the use of “enclothed cognition” where the designs themselves are likely to have influenced the mind of the wearer. We suggest that the historical-social analysis of clothing may benefit from considering the concealed, as well as the explicit, psychologically relevant design features. We suggest that psychosocial interpretations of clothing may help further our understanding of textile and apparel design more generally, even within an historical context.     

Calibration of the charm fine-grained calorimeter

Calorimeters have been used extensively for the study of neutrino interactions in the last decade. This paper describes the need for calibration of such calorimeters and how this was realized for the case of the CHARM fine-grained calorimeter. The energy and spatial response of the calorimeter to both hadronic and electromagnetic showers was measured in π and electron beams from 5 to 140 GeV. The results and resolutions are presented.     

A binary partitioning approach to image compression using weighted finite automata for large images

Fractal-based image compression techniques give efficient decoding time with primitive hardware requirements, and favor real-time communication purposes. One such technique, the weighted finite automata (WFA), is studied on grayscale images. An improved image partitioning technique—the binary or bintree partitioning—is tested on the WFA encoding method. Experimental results show that binary partitioning consistently gives higher compression ratios than the conventional quadtree partitioning method for large images. Moreover, the ability to decode images progressively rendering finer and finer details can be used to display the image over a congested and loss-prone network such as the image transport protocol (ITP) for the Internet, as well as to pave way for multilayered error protection over an often unreliable networking environment. Also, the proposed partitioning approach can be parallelized to reduce its high encoding complexity.     

Exploring the design space of robots: Children''s perspectives

Children's perceptions and evaluations of different robot designs are an important unexplored area within robotics research considering that many robots are specifically designed for children. To examine children's feelings and attitudes towards robots, a large sample of children (N = 159) evaluated 40 robot images by completing a questionnaire for each image, which enquired about robot appearance, robot personality dimensions and robot emotions. Results showed that depending on a robot's appearance children clearly distinguished robots in terms of their intentions (i.e. friendly vs. unfriendly), their capability to understand, and their emotional expression. Results of a principal components analysis of the children's ratings of the robots' personality attributes revealed two dimensions labelled ‘Behavioural Intention’ and ‘Emotional Expression’. Robots were classified according to their scores on these two dimensions and a content analysis of their appearance was conducted in an attempt to identify salient features of different robot personalities. Children judged human-like robots as aggressive, but human–machine robots as friendly. Results on children's perceptions of the robots' behavioural intentions provided tentative empirical support for the Uncanny Valley, hypothesized by (Mori, M., 1970), reflecting a situation where robots are very human-like, but still distinguishable from humans, evoking a feeling of discomfort or repulsion. The paper concludes with a discussion of design implications for robots, and the use of robots in educational contexts.     

Transactional and semantic Indeterminacy in statutory Modelling

In creating legal expert systems to represent statutes the aim of the programmer is to design the model with operational paradigms that reflect, as closely as possible, the working of the statutory representation. This is an indeterminate process. Firstly, it must take account of the reduction of disputes to legal codes or forms of action; in other words the means by which lawyers fit the modalities of common speech into semi‐ritualistic patterns of utterance and practice. Secondly, is the indeterminate, elitist and culturally embedded language of lawyers, for which a justification is professed based on a perception of exactitude and logic This, the paper contends, is not so. Statutory terminology (using the Theft Act 1968 as an exemplar) is, at the least, subject to implicit codes and meanings whilst, at the other extreme, may even be tautological. Both elements create indeterminacy. The object of this paper is to examine the nature of that indeterminacy and suggest mechanisms for overcoming it.     

Phong shading by binary interpolation

This paper presents a new vector interpolation method for Phong shading, referred to as binary interpolation. It can calculate the reflection model by a scalar method. A pre-defined table is used to convert scan lines into segments, each of which is a power of two in length. Then binary interpolation is carried out in each segment. The new method has been tested in two situations; firstly with various sizes of right angled triangles, secondly with the Utah teapot. The results show that, excluding plot to screen time, binary interpolation can decrease the calculation time for a reflection model by about 20%.