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What are emotions and how should we study them? These questions give rise to ongoing controversy amongst scientists in the fields of neuroscience, psychology and philosophy, and have resulted in different views on emotions [ 1–6 ]. In this review, we define emotions as functional states that bear essential roles in promoting survival and thus have emerged through evolution. Emotions trigger behavioral, somatic, hormonal, and neurochemical reactions, referred to as expressions of emotion. We discuss recent studies on emotion expression across species and highlight emerging common principles. We argue that detailed and multidimensional analyses of emotion expressions are key to develop biology-based definitions of emotions and to reveal their neuronal underpinnings. [ABSTRACT FROM AUTHOR]

Abstract: Cryptographic enforcement of access control mechanisms relies on encrypting protected data with the keys stored by authorized users. This approach poses the problem of the distribution of secret keys. In this paper, a key management scheme is presented where each user stores a single key and is capable of efficiently calculating appropriate keys needed to access requested data. The proposed scheme does not require encryption of the same data (key) multiple times with the keys of different users or groups of users. It is designed especially for the purpose of access control. Thanks to that, the space needed for storing public parameters is significantly reduced. Furthermore, the proposed method supports flexible updates when user''s access rights change. [Copyright &y& Elsevier]

Objective: To assess the efficacy of selective salpingography (SSG) with additional tubal catheterization (TC) among infertile patients diagnosed with PTO and analysis of reproductive outcome.Study Design: Retrospective cohort study.Results: Of a total of 399 tubes with confirmed proximal tubal occlusion, 383 successfully restored their patency resulting in 96 % technical success rate. Thirty-five percent of oviducts that had their patency restored was treated with SSG and 65% required additional TC. Reproductive outcomes at minimum 12 months following the treatment were collected by a telephone survey. 21/221 women were lost to follow up. Out of remaining 200 patients with at least one patent tube, 80 patients conceived which resulted in 40 % overall pregnancy rate.Conclusion: Selective salpingography and tubal canalization offer patient-friendly, minimally invasive and cost-effective alternatives to tubal microsurgery and IVF-ET in women with tubal occlusion with very high technical success rate and promising clinical results which depend also on the complexity of couple infertility. Specific indications and limitations make a careful assessment of fallopian tubes and comprehensive evaluation of partners' reproductive situation prior to therapy an absolute requirement. [ABSTRACT FROM AUTHOR]

An increase in the intracellular Ca2+ level in neurons is one of the main steps in the memory formation cascade. The increase results from extracellular Ca2+ influx by activation of ionotropic glutamate receptors and release from intracellular stores by the stimulation of IP3 receptors (IP3Rs) via group I metabotropic glutamate receptors (mGluR1/5). Recent data indicate an additional mechanism resulting in Ca2+ influx into neurons, triggered by intracellular signals that are directly connected to the activation of group I mGluRs. This influx occurs through transient receptor potential (TRP) channels, which are permeable to Na+, K+ and, mainly, Ca2+. These channels are activated by increases in intracellular Ca2+, diacylglycerol (DAC) and inositol 1,4,5-triphosphate (IP3) level resulting from a group I mGluR activation. The aim of the present study was to investigate the participation of TRP channels, especially from TRPC and TRPV groups, in memory consolidation and reconsolidation and memory retrieval processes in a passive avoidance task in one-day old chicks. TRP channels were blocked by the injection of the unspecific channel modulators SKF 96365 (2.5 µl 30 µM/hemisphere) and 2-APB (2.5 µl 10 µM/hemisphere) directly into the intermediate medial mesopallium (IMM) region of the chick brain immediately after initial training or after a reminder. The inhibition of specific TRP channels (TRPV1, TRPV3 or TRPC3) was achieved by the application of selective antibodies. Our results demonstrate that the inhibition of TRP channels by the application of both modulators disrupted memory consolidation, resulting in permanent task amnesia. The inhibition of the TRPV1, TRPC3 and TRPV3 channels by specific antibodies resulted in similar amnesia. Moreover, the inhibition of TRP channels by SKF 96365 and 2-APB at different time points after initial training or after the reminder also resulted in amnesia, indicating the role of TRP channels in memory retrieval. The inhibition of calcium influx through these channels resulted in permanent memory disruption, which suggests that the calcium signal generated by TRP channels is crucial for memory formation and retrieval processes. For the first time, the important role of TRPV3 channels in memory formation was demonstrated. [ABSTRACT FROM AUTHOR]

Obesity affects >600 million people worldwide, a staggering number that appears to be on the rise. One of the lesser known consequences of obesity is its deleterious effects on cognition, which have been well documented across many cognitive domains and age groups. To investigate the cellular mechanisms that underlie obesity-associated cognitive decline, we used diet-induced obesity in male mice and found memory impairments along with reductions in dendritic spines, sites of excitatory synapses, increases in the activation of microglia, the brain's resident immune cells, and increases in synaptic profiles within microglia, in the hippocampus, a brain region linked to cognition. We found that partial knockdown of the receptor for fractalkine, a chemokine that can serve as a "find me" cue for microglia, prevented microglial activation and cognitive decline induced by obesity. Furthermore, we found that pharmacological inhibition of microglial activation in obese mice was associated with prevention of both dendritic spine loss and cognitive degradation. Finally, we observed that pharmacological blockade of microglial phagocytosis lessened obesity-associated cognitive decline. These findings suggest that microglia play an active role in obesity-associated cognitive decline by phagocytosis of synapses that are important for optimal function. [ABSTRACT FROM AUTHOR]

A reoptimization problem describes the following scenario: given an instance of an optimization problem together with an optimal solution for it, we want to find a good solution for a locally modified instance. In this paper, we deal with reoptimization variants of the shortest common superstring problem (SCS) where the local modifications consist of adding or removing a single string. We show the NP-hardness of these reoptimization problems and design several approximation algorithms for them. First, we use a technique of iteratively using any SCS algorithm to design an approximation algorithm for the reoptimization variant of adding a string whose approximation ratio is arbitrarily close to 8/5 and another algorithm for deleting a string with a ratio tending to 13/7. Both algorithms significantly improve over the best currently known SCS approximation ratio of 2.5. Additionally, this iteration technique can be used to design an improved SCS approximation algorithm (without reoptimization) if the input instance contains a long string, which might be of independent interest. However, these iterative algorithms are relatively slow. Thus, we present another, faster approximation algorithm for inserting a string which is based on cutting the given optimal solution and achieves an approximation ratio of 11/6. Moreover, we give some lower bounds on the approximation ratio which can be achieved by algorithms that use such cutting strategies. [ABSTRACT FROM AUTHOR]