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991.
992.
Rafael K. de Andrades Márcio Dorn Daniel S. Farenzena Luis C. Lamb 《Expert systems with applications》2013,40(13):5210-5218
The Medical and Pharmaceutical industries have shown high interest in the precise engineering of protein hormones and enzymes that perform existing functions under a wide range of conditions. Proteins are responsible for the execution of different functions in the cell: catalysis in chemical reactions, transport and storage, regulation and recognition control. Computational Protein Design (CPD) investigates the relationship between 3-D structures of proteins and amino acid sequences and looks for all sequences that will fold into such 3-D structure. Many computational methods and algorithms have been proposed over the last years, but the problem still remains a challenge for Mathematicians, Computer Scientists, Bioinformaticians and Structural Biologists. In this article we present a new method for the protein design problem. Clustering techniques and a Dead-End-Elimination algorithm are combined with a SAT problem representation of the CPD problem in order to design the amino acid sequences. The obtained results illustrate the accuracy of the proposed method, suggesting that integrated Artificial Intelligence techniques are useful tools to solve such an intricate problem. 相似文献
993.
Yen‐Ting Lin Ting‐Wei Yeh Yoshitake Nakajima P. Daniel Dapkus 《Advanced functional materials》2014,24(21):3162-3171
GaN nanorod formation on Ga‐polar GaN by continuous mode metalorganic chemical vapor deposition selective area growth (MOCVD SAG) is achieved under a relatively Ga‐rich condition. The Ga‐rich condition, provided by applying a very low V/III ratio, alters the growth rates of various planes of the defined nanostructure by increasing relative growth rate of the semi‐polar tilted m‐plane {1–101} that usually is the slowest growing plane under continuous growth conditions. This increased growth rate relative to the non‐polar m‐plane {1–100} and even the c‐plane (0001), permits the formation of GaN nanorods with nonpolar sidewalls. In addition, a new growth mode, called the NH3‐pulsed mode, is introduced, utilizing the advantages of both the continuous mode and the lower growth rate pulsed mode to form nanorods. Finally, nanorods grown under the different growth modes are compared and discussed. 相似文献
994.
Daniel Lobo Mauricio Solano George A. Bubenik Michael Levin 《Journal of the Royal Society Interface》2014,11(92)
A fundamental assumption of today''s molecular genetics paradigm is that complex morphology emerges from the combined activity of low-level processes involving proteins and nucleic acids. An inherent characteristic of such nonlinear encodings is the difficulty of creating the genetic and epigenetic information that will produce a given self-assembling complex morphology. This ‘inverse problem’ is vital not only for understanding the evolution, development and regeneration of bodyplans, but also for synthetic biology efforts that seek to engineer biological shapes. Importantly, the regenerative mechanisms in deer antlers, planarian worms and fiddler crabs can solve an inverse problem: their target morphology can be altered specifically and stably by injuries in particular locations. Here, we discuss the class of models that use pre-specified morphological goal states and propose the existence of a linear encoding of the target morphology, making the inverse problem easy for these organisms to solve. Indeed, many model organisms such as Drosophila, hydra and Xenopus also develop according to nonlinear encodings producing linear encodings of their final morphologies. We propose the development of testable models of regeneration regulation that combine emergence with a top-down specification of shape by linear encodings of target morphology, driving transformative applications in biomedicine and synthetic bioengineering. 相似文献
995.
The effect of muscle and intensity of finishing diet on meat quality of foals slaughtered at 15 months was study. For this work, a total of twenty one foals and six muscles: longissimus dorsi (LD), semimembranosus (SM), semitendinosus (ST), biceps femoris (BF), triceps brachii (TB) and Psoas major & minor (PM) from two different intensities of finishing diet (1.5 vs. 3 kg/day) were analysed. 相似文献
996.
The Celta pig is a native breed adapted to the north of Spain and extensive production system. The objective was to study the effects of sex and crossbreeding on carcass characteristics and meat quality. Samples were taken from longissimus dorsi muscle of 52 pigs of three different groups [Celta pure breed (C), Celta crossed with Landrace (C × L) and Celta crossed with Duroc (C × D)]. 相似文献
997.
998.
Dineshbabu Jayagopi Taemie Kim Alex Pentland Daniel Gatica-Perez 《Multimedia Systems》2012,18(1):3-14
Recognizing the conversational context in which group interactions unfold has applications in machines that support collaborative
work and perform automatic social inference using contextual knowledge. This paper addresses the task of discriminating one
conversational context from another, specifically brainstorming from decision-making interactions, using easily computable
nonverbal behavioral cues. Privacy-sensitive mobile sociometers are used to record the interaction data. We hypothesize that
the difference in the conversational dynamics between brainstorming and decision-making discussions is significant and measurable
using speaking activity-based nonverbal cues. We characterize the communication patterns of the entire group by the aggregation
(both temporal and person-wise) of their nonverbal behavior. The results on our interaction data set show that the floor-occupation
patterns in a brainstorming interaction are different from a decision-making interaction, and our method can obtain a classification
accuracy as high as 87.5%. 相似文献
999.
Liu Zhongli Li Yanxiang and Chen Xiang .Technical Center Yantai Taihai Manoir Nuclear Equipment Co. Ltd. Yantai China; . 《中国铸造》2012,(4):313-317
The effect of different tempering temperatures on the microstructure and mechanical properties of airquenched high boron white cast iron was studied.The results indicate that the high boron white cast iron comprises dendritic matrix and inter-dendritic M 2 B boride;and the matrix comprises martensite and pearlite.After quenching in the air,the matrix is changed into lath martensite;but only 1-μm-size second phase exists in the matrix.After tempering,another second phase of several tens of nanometers is found in the matrix,and the size and quantity increase with an increase in tempering temperature.The two kinds of second precipitation phase with different sizes in the matrix have the same chemical formula,but their forming stages are different.The precipitation phase with larger size forms during the austenitizing process,while the precipitation phase with smaller size forms during the tempering process.When tempered at different temperatures after quenching,the hardness decreases with an increase in the tempering temperature,but it increases a little at 450 ℃ due to the precipitation strengthening effect of the second phase,and it decreases greatly due to the martensite decomposition above 450 ℃.The impact toughness increases a little when tempered below 300 ℃,but it then decreases continuously owing to the increase in size and quantity of the secondary precipitate above 300 ℃.Considered comprehensively,the optimum tempering temperature is suggested at 300 ℃ to obtain a good combination of hardness and toughness. 相似文献
1000.