The affinities of antibodies (Abs) for their target antigens (Ags) gradually increase in vivo following an infection or vaccination, but reach saturation at values well below those realisable in vitro. This ‘affinity ceiling’ could in many cases restrict our ability to fight infections and compromise vaccines. What determines the affinity ceiling has been an unresolved question for decades. Here, we argue that it arises from the strength of the chain of protein complexes that is pulled by B cells during the (...) process of Ag acquisition. The affinity ceiling is determined by the strength of the weakest link in the chain. We identify the weakest link and show that the resulting affinity ceiling can explain the Ab affinities realized in vivo, providing a conceptual understanding of Ab affinity maturation. We explore plausible evolutionary underpinnings of the affinity ceiling, examine supporting evidence and alternative hypotheses and discuss implications for vaccination strategies. (shrink)

; tibi M. Bibulus quaerenti se de caelo seruasse respondit idemque in contione dixit, ab Appio tuo fratre productus, te omnino, quod contra auspicia adoptatus esses, tribunum non fuisse. tua denique omnis actio posterioribus mensibus fuit, omnia quae C. Caesar egisset, quod contra auspicia essent acta, per senatum rescindi oportere; quod si fieret, dicebas te tuis umeris me custodem urbis in urbem relaturum.’.

Collaborative filtering recommender system (CFRS) plays a vital role in today’s e-commerce industry. CFRSs collect ratings from the users and predict recommendations for the targeted product. Conventionally, CFRS uses the user-product ratings to make recommendations. Often these user-product ratings are biased. The higher ratings are called push ratings (PRs) and the lower ratings are called nuke ratings (NRs). PRs and NRs are injected by factitious users with an intention either to aggravate or degrade the recommendations of a product. Hence, it (...) is necessary to investigate PRs or NRs and discard them. In this work, opinion mining approach is applied on textual reviews that are given by users for a product to detect the PRs and NRs. The work also examines the effect of PRs and NRs on the performance of CFRS by evaluating various measures such as precision, recall, F-measure and accuracy. (shrink)

Building on a base of simple economic theory and elementary linear algebra and calculus, this broad treatment of static and dynamic optimization methods discusses the importance of shadow prices and functions defined by solutions of optimization problems.

Recommender system depends on the thoughts of numerous users to predict the favourites of potential consumers. RS is vulnerable to malicious information. Unsuitable products can be offered to the user by injecting a few unscrupulous “shilling” profiles like push and nuke attacks into the RS. Injection of these attacks results in the wrong recommendation for a product. The aim of this research is to develop a framework that can be widely utilized to make excellent recommendations for sales growth. This study (...) uses the methodology that presents an enhanced clustering algorithm named as modified density peak clustering algorithm on the consumer review dataset to ensure a well-formed cluster. An improved recurrent neural network algorithm is proposed to detect these attacks in hybrid RS, which uses the content-based RS and collaborative filtering RS. The results are compared with other state of the art algorithms. The proposed method is more suitable for E-commerce applications where the number of customers and products grows rapidly. (shrink)

There is a long history to the debate of nationalism. The Indian nationalism has emerged after a long people’s movement the truth to which is often denied by a range of forces who have ideological leanings towards the ideology of Hindutwa. This paper is an attempt to revisit the historical context in which Indian nationalism has emerged and evaluate it in reference to the contemporary time. It emphasizes on the relation between the nation and the state with special reference to (...) its impact on the universities. Further, the paper suggests that in order to uphold the idea of university and nation, an inclusive and secular idea of nation has to be espoused. Lastly, it suggests that a university needs to foster a non sectarian approach and broaden its vision for an internationalist outlook. (shrink)

The presence of vegetation on railway tracks threatens track safety and longevity. However, vegetation inspections in Sweden are currently being carried out manually. Manually inspecting vegetation is very slow and time consuming. Maintaining an even quality standard is also very difficult. A machine vision-based approach is therefore proposed to emulate the visual abilities of the human inspector. Work aimed at detecting vegetation on railway tracks has been split into two main phases. The first phase is aimed at detecting vegetation on (...) the tracks using appropriate image analysis techniques. The second phase is aimed at detecting the rails in the image to determine the cover of vegetation that is present between the rails as opposed to vegetation present outside the rails. Results achieved in the current work indicate that the machine vision approach has performed reasonably well in detecting the presence/absence of vegetation on railway tracks when compared with a human operator. (shrink)

Study of four works of Sri Krishna Prem, 1898-1965, a Vaishnavite teacher; includes a bibliographical sketch.

Spatially and temporally restricted expression of Hox genes requires multiple mechanisms at both the transcriptional and the post-transcriptional levels. New insight into this precise expression mechanism comes from recent findings of a novel sense–antisense miRNA combination from the bithorax complex of Drosophila melanogaster.1-4 These two miRNAs encoded from the same locus target 3′ untranslated regions of anterior hox genes, Antp, Ubx and abd-A to establish the dominance of posterior hox gene Abd-B in its expression domain. Such double-edge tools, sense–antisense miRNA (...) combinations, also operate at multiple loci in the genome implicating their wider impact on the post-transcriptional gene regulation in eukaryotes. BioEssays 30:1058–1061, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

Xeroxed drafts. The originals are held in the University Library, University of Lund, Sweden.

The present article attempts to examine the relationship between learning agility and authentic leadership development. The recent rise in the cases of fraud involving leaders at various levels in the organizations, and the resulting distrust among the employees towards their leaders, points to the need to have authentic leaders, given the positive organizational outcomes associated with this leadership approach. Further, scholars have suggested that leadership development is possible through learning from one’s life experiences. The developmental definition of authentic leadership also (...) reflects the importance of learning from past experiences. Yet, studies have largely overlooked to explore the association between learning agility and authentic leadership development. This paper further tries to analyze the moderating effects of learning goal orientation and organizational culture on this relationship. Therefore, based on the existing research, the associations among these factors have been delineated and a conceptual model has been presented along with several propositions. Implications for future research and limitations of this work have also been discussed towards the end. (shrink)

Phosphatidylinositol 4,5‐bisphosphate (PI4,5P2) is a key lipid signaling molecule that regulates a vast array of biological activities. PI4,5P2 can act directly as a messenger or can be utilized as a precursor to generate other messengers: inositol trisphosphate, diacylglycerol, or phosphatidylinositol 3,4,5‐trisphosphate. PI4,5P2 interacts with hundreds of different effector proteins. The enormous diversity of PI4,5P2 effector proteins and the spatio‐temporal control of PI4,5P2 generation allow PI4,5P2 signaling to control a broad spectrum of cellular functions. PI4,5P2 is synthesized by phosphatidylinositol phosphate kinases (...) (PIPKs). The array of PIPKs in cells enables their targeting to specific subcellular compartments through interactions with targeting factors that are often PI4,5P2 effectors. These interactions are a mechanism to define spatial and temporal PI4,5P2 synthesis and the specificity of PI4,5P2 signaling. In turn, the regulation of PI4,5P2 effectors at specific cellular compartments has implications for understanding how PI4,5P2 controls cellular processes and its role in diseases. (shrink)

When imposing traffic congestion pricing around downtown commercial centers, there is a concern that commercial activities will have to consider relocating due to reduced demand, at a cost to merchants. Concerns like these were important in the debates before the introductions of congestion charges in both London and Stockholm and influenced the final policy design choices. This study introduces a sequential experimental game to study reactions to congestion pricing in the commercial sector. In the game, merchants first make location choices. (...) Consumers, who drive to do their shopping, subsequently choose where to shop. Initial responses to the introduction of congestion pricing and equilibrium selection adjustments over time are observed. These observations are compared to responses and adjustments in a condition where congestion pricing is reduced from an initially high level. Payoffs are non-linear and non-transparent, making it less than obvious that the efficient equilibrium will be selected, and introducing possibilities that participants need to discover their preferences and anchor on past experiences. We find that initial responses reflect standard inverse price–demand relations, and that adjustments over time rely on signaling by consumers leading to the efficient equilibrium. There is also evidence that priming from initial experiences influence play somewhat. We confirm that commercial activities relocate following the introduction of congestion pricing and that the adjustment process is costly to merchants. (shrink)

. Speaker recognition has been an active research area for many years. Methods to represent and quantify information embedded in speech signal are termed as features of the signal. The features are obtained, modeled and stored for further reference when the system is to be tested. Decision whether to accept or reject speakers are taken based on parameters of the data modeling techniques. Real world offers various degradations to the signal that hamper the signal quality. The degradations may be due (...) to ambient background noise, reverberation or multispeaker scenario. This paper presents a survey of various feature extraction, data modeling methods, metrics that are used to take the decisions and methods that can be used to preprocess the degraded data that have been used to perform the task of speaker recognition. (shrink)