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This chapter reviews current literature on hormonal and neural signals critical for the regulation of individual meals and body fat. Body weight is regulated via an ongoing process called energy homeostasis, or the long-term matching of food intake to energy expenditure. Reductions from an individual's "normal" weight due to lack of sufficient food lowers levels of adiposity signals (leptin and insulin) reaching the brain from the blood, activates anabolic hormones that stimulate food intake, and decreases the efficacy of meal-generated signals (such as cholecystokinin, or CCK) that normally reduce meal size. A converse sequence of events happens when individuals gain weight: adiposity signals are increased, catabolic hormones are stimulated, and the consequence is a reduction in food intake and a normalization of body weight. The brain also functions as a "fuel sensor" and thereby senses nutrients and generates signals and activation of neuronal systems and circuits that regulate energy homeostasis. This chapter focuses on how these signals are received and integrated by the central nervous system. [ABSTRACT FROM AUTHOR]

NK cells have the innate ability to recognize and eliminate transformed cells. However, tumors still form and progress in seemingly immune-competent individuals. The tumor microenvironment controls NK recruitment and maintenance in situ. Current understanding of NK basic biology explain in part their limitations, that might turn the anti-cancerous devotion into a tumor progression outcome. Recent progress in understanding of the evasion from NK recognition and counterattack against the killer cells are discussed, along with unresolved questions. [ABSTRACT FROM AUTHOR]

In human mesenchymal stem cells the envelope surrounding the nucleus, as visualized by the nuclear lamina, has a round and flat shape. The lamina structure is considerably deformed after activation of cell death (apoptosis). The spatial organization of the lamina is the initial structural change found after activation of the apoptotic pathway, therefore can be used as a marker to identify cells activated for apoptosis. Here we investigated whether the spatial changes in lamina spatial organization can be recognized by machine learning algorithms to classify normal and apoptotic cells. Classical machine learning algorithms were applied to classification of 3D image sections of nuclear lamina proteins, taken from normal and apoptotic cells. We found that the Evolutionary-optimized Support Vector Machine (SVM) algorithm succeeded in the classification of normal and apoptotic cells in a highly satisfying result. This is the first time that cells are classified based on lamina spatial organization using the machine learning approach. We suggest that this approach can be used for diagnostic applications to classify normal and apoptotic cells. [ABSTRACT FROM AUTHOR]

We consider the numerical evolutionary optimization of dynamic molecular alignment by shaped femtosecond laser pulses. We study a simplified model of this quantum control problem, which allows the full physical investigation of the optimal solutions. By using specific variants of Derandomized Evolution Strategies, subject to parameterizations which are known to be superior for this problem, the numerical results reveal different conceptual physics structures for the different optimization procedures. These results are strong both from the algorithmic as well as from the physics perspectives. This shows that Natural Computing techniques can be used to derive new insights into Physics. [ABSTRACT FROM AUTHOR]

This chapter reviews current literature on hormonal and neural signals critical for the regulation of individual meals and body fat. Body weight is regulated via an ongoing process called energy homeostasis, or the long-term matching of food intake to energy expenditure. Reductions from an individual's "normal" weight owing to a lack of sufficient food lowers levels of adiposity signals (leptin and insulin) reaching the brain from the blood, activates anabolic hormones that stimulate food intake, and decreases the efficacy of meal-generated signals (such as cholecystokinin) that normally reduce meal size. A converse sequence of events happens when individuals gain weight, adiposity signals are increased, catabolic hormones are stimulated, and the consequence is a reduction in food intake and a normalization of body weight. The brain also functions as a "fuel sensor" and thereby senses nutrients and generates signals and activation of neuronal systems and circuits that regulate energy homeostasis. This chapter focuses on how these signals are received and integrated by the central nervous system. [ABSTRACT FROM AUTHOR]

Evolutionary Algorithms (EAs), popular search methods for optimization problems, are known for successful and fast location of single optimal solutions. However, many complex search problems require the location and maintenance of multiple solutions. Niching methods, the extension of EAs to address this issue, have been investigated up to date mainly within the field of Genetic Algorithms (GAs), and their applications were limited to low-dimensional search problems. In this paper we present in detail the background for niching methods within Evolution Strategies (ES), and discuss two ES niching methods, which have been introduced recently and have been tested only for theoretical functions. We describe the application of those ES niching methods to a challenging real-life high-dimensional optimization problem, namely Femtosecond Laser Pulse Shaping. The methods are shown to be robust and to achieve satisfying results for the given problem. [ABSTRACT FROM AUTHOR]

The popular abstraction/refinement model frequently used in verification, can also explain the success of a SAT decision heuristic like Berkmin. According to this model, conflict clauses are abstractions of the clauses from which they were derived. We suggest a clause-based decision heuristic called Clause-Move-To-Front (CMTF), which attempts to follow an abstraction/refinement strategy (based on the resolve-graph) rather than satisfying the clauses in the chronological order in which they were created, as done in Berkmin. We also show a resolution-based score function for choosing the variable from the selected clause and a similar function for choosing the sign. We implemented the suggested heuristics in our SAT solver . Experiments on hundreds of industrial benchmarks demonstrate the superiority of this method comparing to the Berkmin heuristic. There is still room for research on how to explore better the resolve-graph information, based on the abstraction/refinement model that we propose. [ABSTRACT FROM AUTHOR]

Diffusion Tensor Imaging (DTI) became a popular tool for white matter tract visualization in the brain. It provides quantitative measures of water molecule diffusion anisotropy and the ability to delineate major white matter bundles. The diffusion model of DTI was found to be inappropriate in cases of partial volume effect, such as Multiple Fiber Orientations (MFO) ambiguity. Recently, a variety of image processing methods were proposed to enhance DTI results by reducing noise and correcting artifacts, but most techniques were not designed to resolve MFO ambiguity. In this Chapter we describe variational based DTI processing techniques, and show how such techniques can be adapted to the Multiple Tensor (MT) diffusion model via the Multiple Tensor Variational (MTV) framework. We show how the MTV framework can be used in separating differently oriented white matter fiber bundles. [ABSTRACT FROM AUTHOR]

Drawing on a variety of lithic and faunal data from Hayonim, Kebara, Amud, and other well-documented sites in the Levant and adjacent areas, as well as information on numbers of sites, intensity of occupations, and internal structure of occupations, this paper explores broad changes in the nature of settlement patterns over the roughly 200,000 years of the Levantine Middle Paleolithic. The most readily visible differences between the early and late Mousterian are about numbers of people on the landscape—rates and timing of visitation and, perhaps, the sizes of the social groups present. From the point of view of site structure, we see substantive contrasts between Hayonim and Kebara caves and the successive phases of the Mousterian that they represent. Hayonim seems to be characterized by redundant, spot-specific use of domestic space, whereas Kebara displays a more rigidly partitioned and persistent spatial pattern, probably in response to higher rates of debris generation and more frequent visitation. Convincing indications of more people in the later Mousterian appear as two spatial aspects of the archaeological record: internal differentiation in site structure during the later Mousterian and, on a geographic scale, greater numbers of sites that may also be richer in material. Our principal conclusion, best viewed at this stage as a working hypothesis, is that the changes in settlement patterns between the early and the late Middle Paleolithic reflect an increase in regional population, as well as shifts in forager mobility in response to seasonal and eventually long-term changes in resource distribution and abundance. We believe that these settlement changes are most parsimoniously accounted for by reference to a combination of demographic and paleoecological factors rather than by positing a change in the cognitive capacities of local or intrusive populations. [ABSTRACT FROM AUTHOR]

We introduce a new decision procedure for Equality Logic. The procedure improves on Bryant and Velev's sparse method [4] from CAV'00, in which each equality predicate is encoded with a Boolean variable, and then a set of transitivity constraints are added to compensate for the loss of transitivity of equality. We suggest the Reduced Transitivity Constraints (RTC) algorithm, that unlike the sparse method, considers the polarity of each equality predicate, i.e. whether it is an equality or disequality when the given equality formula ϕE is in Negation Normal Form (NNF). Given this information, we build the Equality Graph corresponding to ϕE with two types of edges, one for each polarity. We then define the notion of Contradictory Cycles to be cycles in that graph that the variables corresponding to their edges cannot be simultaneously satisfied due to transitivity of equality. We prove that it is sufficient to add transitivity constraints that only constrain Contradictory Cycles, which results in only a small subset of the constraints added by the Reconstruct-αsparse method. The formulas we generate are smaller and define a larger solution set, hence are expected to be easier to solve, as indeed our experiments show. Our new decision procedure is now implemented in the uclid verification system. [ABSTRACT FROM AUTHOR]

Counterexample-Guided Abstraction Refinement (cegar) techniques have been very successful in model checking large systems. While most previous work has focused on model checking, this paper presents a Counterexample-Guided abstraction refinement technique for Bounded Model Checking (bmc). Our technique makes bmc much faster, as indicated by our experiments. bmc is also used for generating refinements in the Proof-Based Refinement (pbr) framework. We show that our technique unifies pbr and cegar into an abstraction-refinement framework that can balance the model checking and refinement efforts. [ABSTRACT FROM AUTHOR]

Mixed Group Ranks is a parametric method for combining rank based classifiers that is effective for many-class problems. Its parametric structure combines qualities of voting methods with best rank approaches. In [1] the parameters of MGR were estimated using a logistic loss function. In this paper we describe how MGR can be cast as a probability model. In particular we show that using an exponential probability model, an algorithm for efficient maximum likelihood estimation of its parameters can be devised. While casting MGR as an exponential probability model offers provable asymptotic properties (consistency), the interpretability of probabilities allows for flexiblity and natural integration of MGR mixture models. [ABSTRACT FROM AUTHOR]

We present an algorithmic framework for phoneme classification where the set of phonemes is organized in a predefined hierarchical structure. This structure is encoded via a rooted tree which induces a metric over the set of phonemes. Our approach combines techniques from large margin kernel methods and Bayesian analysis. Extending the notion of large margin to hierarchical classification, we associate a prototype with each individual phoneme and with each phonetic group which corresponds to a node in the tree. We then formulate the learning task as an optimization problem with margin constraints over the phoneme set. In the spirit of Bayesian methods, we impose similarity requirements between the prototypes corresponding to adjacent phonemes in the phonetic hierarchy. We describe a new online algorithm for solving the hierarchical classification problem and provide worst-case loss analysis for the algorithm. We demonstrate the merits of our approach by applying the algorithm to synthetic data and as well as speech data. [ABSTRACT FROM AUTHOR]

The Closed-World Assumption (CWA) on a database expresses that an atom not in the database is false. The CWA is only applicable in domains where the database has complete knowledge. In many cases, for example in the context of distributed databases, a data source has only complete knowledge about part of the domain of discourse. In this paper, we introduce an expressive and intuitively appealing method of representing a local closed-world assumption (LCWA) of autonomous data-sources. This approach distinguishes between the data that is conveyed by a data-source and the meta-knowledge about the area in which these data is complete. The data is stored in a relational database that can be queried in the standard way, whereas the meta-knowledge about its completeness is expressed by a first order theory that can be processed by an independent reasoning system (for example a mediator). We consider different ways of representing our approach, relate it to other methods of representing local closed-word assumptions of data-sources, and show some useful properties of our framework which facilitate its application in real-life systems. [ABSTRACT FROM AUTHOR]

We introduce a declarative approach for a coherent composition of autonomous databases. For this we use ID-logic, a formalism that extends classical logic with inductive definitions. We consider ID-logic theories that express, at the same time, the two basic challenges in database composition problems: relating different schemas of the local databases to one global schema (schema integration) and amalgamating the distributed and possibly contradictory data to one consistent database (data integration). We show that our framework supports different methods for schema integration (as well as their combinations) and that it provides a straightforward way of dealing with inconsistent data. Moreover, this framework facilitates the implementation of database repair and consistent query answering by means of a variety of reasoning systems. [ABSTRACT FROM AUTHOR]

We present an improvement to the Hyper preprocessing algorithm that was suggested by Bacchus and Winter in SAT 2003 [1]. Given the power of modern SAT solvers, Hyper is currently one of the only cost-effective preprocessors, at least when combined with some modern SAT solvers and on certain classes of problems. Our algorithm, although it produces less information than Hyper, is much more efficient. Experiments on a large set of industrial Benchmark sets from previous SAT competitions show that HyperBinFast is always faster than Hyper (sometimes an order of magnitude faster on some of the bigger CNF formulas), and achieves faster total run times, including the SAT solver's time. The experiments also show that HyperBinFast is cost-effective when combined with three state-of-the-art SAT solvers. [ABSTRACT FROM AUTHOR]

In this paper, Ginsberg's/Fitting's theory of bilattices is invoked as a natural accommodation and powerful generalization to both intuitionistic fuzzy sets (IFSs) and interval-valued fuzzy sets (IVFSs), serving on one hand to clarify the exact nature of the relationship between these two common extensions of fuzzy sets, and on the other hand providing a general and intuitively attractive framework for the representation of uncertain and potentially conflicting information. [ABSTRACT FROM AUTHOR]

We studied patterning mechanisms acting on the formation of new mouths during regeneration of wedgeshaped fragments of the solitary coral Fungia granulosa. Mouth formation dynamics was studied in fragments taken from different parts of the adult polyp. The corals were fragmented into central and peripheral fragments in relation to each polyp's centrally positioned mouth. The study revealed that the maintenance of the original body plan and growth axis during the process of regeneration, appears to depend on the existence of the polyp's mouth. When damage to the coral polyp includes only partial damage to the original mouth, the regeneration process is characterized by maintenance of the growth axis and body plan. By contrast, complete removal of the original mouth results in the formation of multiple mouths and is followed by a drastic change in body plan and growth axis. Some of these mouths develop later into new polyps, which eventually detach from the original coral. During the first 2-3 mo of regeneration, ‘preliminary' mouths developed and regressed until stabilization was attained. The appearance of new mouths in fragments farther from the original mouth (peripheral fragments) preceded by a week the appearance of new mouths in fragments that were more proximal to the original mouth (central fragments). Additionally, more mouths formed in peripheral than in central fragments. We interpret the results in light of the developmental model suggested by Meinhardt for Hydra. The formation of new mouths in regenerating fragments of Fungia is explained in terms of a source density gradient field, auto-activation, and lateral inhibition exerted by the original central mouth. These effectors determine the position and timing of mouth(s) development. Key words: morphogenetic gradients, pattern formation, regeneration, scleractinian coral, Fungia granulosa [ABSTRACT FROM AUTHOR]

This chapter entitled Challenges in Glycoinformatics will review new themes in describing and archiving glycostructures, their interface with the analysis tools and how to extract relevant glycomic data out of those. Glycoinformatics is the common technology and electronic language that connects the field of glycobiology. It allows the presentation, and the description of glycomolecules in a useful way that enables their utilization and manipulation. Glycoinformatics further permits pathway and systemic analysis of glycans to create diagnostic tools, aid in drug discovery and development, and develop biotechnological applications for food, medicine and industry. The technologies enabling this are now only emerging, and new abilities are now developed. The developments in technologies and in strategies for using data require progress and re-evaluation in the field of glycoinformatics. [ABSTRACT FROM AUTHOR]

We present a new, distributed e-voting protocol, which does not require any ‘conventional' cryptography, or other means of non-trivial math, and is information-theoretically secure. In our system, the voter receives a receipt confirming her vote, and does not need to trust any pollster to correctly encrypt her vote, or convey it to the talliers. The system can withstand corruption of almost half the number of authorities running the elections. To achieve these goals, we present enhanced check vectors, a new weak signature scheme as well as a new protocol for joint creation of weak signatures by multiple servers. [ABSTRACT FROM AUTHOR]

Cystic fibrosis (CF) is a single-gene disorder with a complex phenotype, in which multiple organs are affected. The pulmonary complications of CF, including mucous plugging and chronic bacterial infection of the lung, represent the major cause of morbidity and mortality (1). It has long been suggested that mutations in CFTR, localized to the apical membrane of airway epithelia, lead to abnormalities in the fluid lining the airway surface. Accumulating evidence suggests that the inflammatory response in the CF lung may be excessive. However, it is not clear to what extent this reflects unusual persistence of stimulation of this response by bacteria or other pathogens, vs to what extent defects in CFTR might by themselves stimulate or cause dysregulation of inflammatory responses. Changes in the multigene patterns of expression can provide clues about regulatory mechanisms and broader cellular functions and biochemical pathways. In the context of cystic fibrosis disease and treatment, the knowledge gained from these types of measurements can help determine the causes and consequences of disease, how drugs and drug candidates work in cells and organisms, and what gene products might have therapeutic uses themselves or may be appropriate targets for therapeutic intervention. [ABSTRACT FROM AUTHOR]

It has been known for over 50 years that the amount of nuclear chromatin (DNA) in malignant neoplasms differs from that of homologous normal cells (1). More recently, it has been shown that nuclear DNA content correlates with the clinical outcome of various human neoplasms including urologic malignancies (2-10). An important problem in the care of patients with renal cell carcinoma (RCC) is the prediction of the neoplasms malignant potential, and in turn the patient's prognosis. Various parameters have been used to assess the malignant potential of renal cell carcinoma, including clinical and pathologic stage, histologic grade, tumor size, nuclear morphology, immunohistochemistry, age, elevated erythrocyte sedimentation rate, and hypercalcemia. To date, the most important predictors of prognosis in patients with RCC have been tumor pathologic stage, histologic grade and type (11,12). However, it has been shown that patients within a specified stage and grade may differ in their disease progression and survival (13,14). Furthermore, none of these variables alone or in combination has shown to provide total reliable prognostic information for the individual patient. These reasons led several groups to evaluate the prognostic value of nuclear DNA content in patients with renal cell carcinoma. [ABSTRACT FROM AUTHOR]

The 2dF Galaxy Redshift Survey has already yielded over 130,000 galaxy spectra (out of the planned 250,000). We present a method for the parameterisation of galaxy spectra in the 2dF and other large redshift surveys using a new continuous parameter $\eta = 0.44pc_1 - pc_2$, based on a Principal Components Analysis (where pc1 and pc2 are the projections onto the first and second principal components respectively). This parameter is designed to be robust to instrumental uncertainties and it represents the absorption/emission strength of a galaxy. [ABSTRACT FROM AUTHOR]

Methods for compression and classification of galaxy spectra, which are useful for large galaxy redshift surveys (such as the SDSS, 2dF, 6dF and VIRMOS), are reviewed. In particular, we describe and contrast three methods: (i) Principal Component Analysis, (ii) Information Bottleneck, and (iii) Fisher Matrix. We show applications to 2dF galaxy spectra and to mock semi-analytic spectra, and we discuss how these methods can be used to study physical processes of galaxy formation, clustering and galaxy biasing in the new large redshift surveys. [ABSTRACT FROM AUTHOR]

We report results from the first 1000 square arc-minutes of the Las Campanas IR survey. We have imaged 1 square degree of high latitude sky in six distinct fields to a $5\sigma$ H-band depth of 20.5 (Vega). Optical imaging in the V,R,I, and z' bands allow us to select color subsets and photometric-redshift-defined shells. We show that the angular clustering of faint red galaxies ( 18 < H < 20.5, I - H > 3) is an order of magnitude stronger than that of the complete H-selected field sample. We employ three approaches to estimate n(z) in order to invert $w(\theta)$ to derive r0. We find that our n(z) is well described by a Gaussian with $ < z > = 1.2, \sigma (z) = 0.15$. From this we derive a value for r0 of 7+2-1 co-moving h-1Mpc at < z > = 1.2. This is a factor of $\sim 2$ larger than the clustering length for Lyman break galaxies and is similar to the expectation for early type galaxies at this epoch. [ABSTRACT FROM AUTHOR]

Bounded Model Checking based on SAT methods has recently been introduced as a complementary technique to BDD-based Symbolic Model Checking. The basic idea is to search for a counter example in executions whose length is bounded by some integer k. The BMC problem can be efficiently reduced to a propositional satisfiability problem, and can therefore be solved by SAT methods rather than BDDs. SAT procedures are based on general-purpose heuristics that are designed for any propositional formula. We show that the unique characteristics of BMC formulas can be exploited for a variety of optimizations in the SAT checking procedure. Experiments with these optimizations on real designs proved their efficiency in many of the hard test cases, comparing to both the standard SAT procedure and a BDD-based model checker. [ABSTRACT FROM AUTHOR]

Closed economies, especially highly industrialized ones, have much to gain in efficiency, in production, and in welfare from opening themselves up to world markets and free trade. This basic principle has manifested itself in recent decades through the vigorous export-led growth witnessed in a significant number of industrializing countries. It is even more appropriate for economies in transition: in addition to correcting their structural distortions and directing them toward true comparative-advantage trade patterns, opening up also introduces the principles of market economy to their domestic markets. Yet the generally radical liberalization of the trade regime and the almost full convertibility of the local currency in many formerly socialist countries were unable to prevent the initial downward trend in production. This has been partly explained by the large extent and bulkiness of the needed changes, by the high transaction (transition) costs, and by the lack of the time and resources necessary for appropriate restructuring. On the other hand, successful reorientation of trade toward the West was highly correlated with successful internal transition and with resumed economic growth (World Bank, 1996b; EBRD, 1996, EBRD, 1997, EBRD, 1998). Among the former socialist countries, Russia stands out as the largest country, the one most in need of restructuring, and the country with the most particular structure of comparative advantage arising from its vast natural resources. [ABSTRACT FROM AUTHOR]