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Background: Elevated spleen stiffness may be seen in patients with portal hypertension due to cirrhosis. In patients with Fontan physiology, elevated liver stiffness has been shown to correlate poorly with liver fibrosis. It is unknown whether spleen stiffness may instead serve as a surrogate marker of liver fibrosis in these patients. Objective: To compare spleen stiffness determined by shear wave elastography (SWE) with histological findings of an ultrasound-guided liver biopsy in patients who had undergone Fontan palliation as a potential surrogate for Fontan-associated liver disease. Materials and methods: This was an IRB-approved single-center, retrospective study. Patients with Fontan palliation who had undergone both a spleen SWE study and a percutaneous liver biopsy between 2016 and 2020 were included. Biopsy, performed during cardiac catheterization, within 3 months of the SWE was required for inclusion. Using Kruskal–Wallis tests, spleen stiffness was compared with three liver biopsy scoring methods: Ishak, METAVIR, and congestive hepatic fibrosis score (CHFS). When available, Pearson's correlation was also used to compare collagen deposition determined using Sirius Red stain (%SR) with SWE values. A P-value < 0.05 was considered statistically significant. Results: Twenty-two patients (15 males) were included in the study, with a median age of 17 years (IQR is 14.8–20.5 years; age range: 7 years to 30.2 years). The median spleen stiffness was 2.94 m/s (IQR: 2.57–3.61 m/s; range: 1.48–4.27 m/s). The median Fontan pressure was 11 mm Hg (IQR: 10–13.3 mm Hg; range: 7–19 mm Hg) obtained within a median of 10 days (IQR: 1–41 days) of SWE. Splenic stiffness did not correlate with the extent of fibrosis determined by histology (all P > 0.05). There was also no statistically significant correlation between the %SR staining and SWE-determined spleen stiffness (Pearson's correlation of 0.165, P = 0.59, n = 13). Conclusions: In this preliminary study, SWE spleen stiffness values did not correlate with biopsy-determined scoring of liver fibrosis in patients with Fontan physiology. [ABSTRACT FROM AUTHOR]

The method of brackets is a method for the evaluation of definite integrals based on a small number of rules. This is employed here for the evaluation of Mellin–Barnes integral. The fundamental idea is to transform these integral representations into a bracket series to obtain their values. The expansion of the gamma function in such a series constitute the main part of this new application. The power and flexibility of this procedure is illustrated with a variety of examples. [ABSTRACT FROM AUTHOR]

The possible role played by individual attributes, sociodemographic characteristics and/or ecological pressures in the interaction between animals and the development of social relationships between them is of great interest in animal ecology and evolutionary biology. Social Network Analysis is an ideal tool to study these types of questions. The Animal Network Toolkit Software (ANTs) R package was specifically developed to provide all the different social network analysis techniques currently used in the study of animal social networks. This global package enables users to (1) compute global, polyadic and nodal network measures; (2) perform data randomisation: data stream and network (node and link) permutations; (3) perform statistical permutation tests for static or temporal network analyses, and (4) visualise networks. ANTs allows researchers to perform multilevel network analyses ranging from individual network measures to interaction patterns and the analysis of the overall network structure, and carry out static or temporal network analyses without switching between different R packages, thus making a substantial contribution to advances in the study of animal behaviour. ANTs outperforms existing R packages for the computation speed of network measures and permutations. [ABSTRACT FROM AUTHOR]

Group-living animals rely on efficient transmission of information for optimal exploitation of their habitat. How efficient and resilient a network is depend on its structure, which is a consequence of the social interactions of the individuals that comprise the network. In macaques, network structure differs according to dominance style. Networks of intolerant species are more modular, more centralized, and less connected than those of tolerant ones. Given these structural differences, networks of intolerant species are potentially more vulnerable to fragmentation and decreased information transmission when central individuals disappear. Here we studied network resilience and efficiency in artificial societies of macaques. The networks were produced with an individual-based model that has been shown to reproduce the structural features of networks of tolerant and intolerant macaques. To study network resilience, we deleted either central individuals or individuals at random and studied the effects of these deletions on network cohesiveness and efficiency. The deletion of central individuals had more negative effects than random deletions from the networks of both tolerant and intolerant artificial societies. Central individuals thus appeared to aid in the maintenance of network cohesiveness and efficiency. Further, the networks of both intolerant and tolerant societies appeared to be robust to the loss of individuals, as network fragmentation was never observed. Our results suggest that despite differences in network structure, networks of tolerant and intolerant macaques may be equally resilient. [ABSTRACT FROM AUTHOR]

Since group-living animals are embedded in a network of social interactions, socioecological factors may not only affect individual behavioral strategies but also the patterning of group-level social interactions, i.e., the network structure. These co-variations between socioecological factors, individual behavior, and group-level structure are important to study since ecological factors may strongly influence animal health outcomes and reproductive success. Besides factors such as social information and/or infectious agents, with far-reaching individual fitness consequences, seem independent of individuals' own social interactions but directly affected by the topology of the social network. This paper reviews how socio-ecological pressures, i.e., causal factors (food distribution, predation, and infectious agent risk), via intermediary mechanisms (stress, information sharing, and mating system), may affect individual social behavior and consequently, social network topology. We also discuss how evolutionary driving forces, genetic (i.e., genes) and cultural (i.e., learned behavior) selection, may result in a specific composition of individuals' social strategies that produce network topologies that might be optimized to specific socio-ecological conditions. We conclude that studies focusing on whether and how well networks resist changing conditions might provide a better understanding of the rules underlying individual behavior, which in turn influences network topology—a process we have called network evolution. Evolutionary processes may favor a group phenotypic composition, thus a network topology. This has been referred to as a "collective social niche construction". [ABSTRACT FROM AUTHOR]

The two neuropathological hallmarks of Alzheimer's disease (AD) are amyloid-[Formula: see text] plaques and neurofibrillary tangles of tau protein. Fifteen years ago, Positron Emission Tomography (PET) with Pittsburgh Compound B (11C-PiB) enabled selective in-vivo visualization of amyloid-[Formula: see text] plaque deposits and has since provided valuable information about the role of amyloid-[Formula: see text] deposition in AD. The progression of tau deposition has been shown to be highly associated with neuronal loss, neurodegeneration, and cognitive decline. Until recently it was not possible to visualize tau deposition in-vivo, but several tau PET tracers are now available in different stages of clinical development. To date, no tau tracer has been approved by the Food and Drug Administration for use in the evaluation of AD or other tauopathies, despite very active research efforts. In this paper we review the recent developments in tau PET imaging with a focus on in-vivo findings in AD and discuss the challenges associated with tau tracer development, the status of development and validation of different tau tracers, and the clinical information these provide. [ABSTRACT FROM AUTHOR]

We observe a property of orthogonality of the Mellin-Barnes transformation of triangle one-loop diagrams, which follows from our previous papers (Kondrashuk and Kotikov in JHEP 0808:106, 2008; Kondrashuk and Vergara in JHEP 1003:051, 2010; Allendes et al. in J Math Phys 51:052304, 2010). In those papers it has been established that Usyukina-Davydychev functions are invariant with respect to the Fourier transformation. This has been proved at the level of graphs and also via the Mellin-Barnes transformation. We partially apply to the one-loop massless scalar diagram the same trick in which the Mellin-Barnes transformation was involved and obtain the property of orthogonality of the corresponding MB transforms under integration over contours in two complex planes with certain weight. This property is valid in an arbitrary number of dimensions. [ABSTRACT FROM AUTHOR]

The genetic state of the arbuscular mycorrhizal fungus species Rhizophagus irregularis differs among isolates, including both homokaryotic and dikaryotic isolates. Via the production of multi-nucleate axexual spores, siblings of dikaryotic isolates may inherit unequal frequencies of nucleotypes. Using bg112, a microsatellite marker, previous studies revealed that lines deriving from single spores of the dikaryotic R. irregularis isolate C3 differed in their proportions of different alleles. A genomic study of single nuclei of R. irregularis, however, suggested that this marker was a multi-copy locus and that therefore it was inappropriate to study the inheritance of nuclei in dikaryotic isolates. In this study, we first analysed whole genome data of several R. irregularis isolates and demonstrated that bg112 is indeed a single copy locus in these genomes. Thus, the bg112 locus is a suitable marker to study the relative frequency of nucleotypes in R. irregularis. Second, by using amplicon sequencing, we confirmed the existence of one allele of bg112 in two homokaryotic isolates (DAOM197198 and C2) and two alleles in the dikaryotic isolate (C3). Finally, we found that the relative proportions of two bg112 alleles differed significantly among dikaryotic single-spore lines derived from isolate C3, indicating that genetically different nucleotypes are inherited unequally in this dikaryotic R. irregularis isolate. [ABSTRACT FROM AUTHOR]

Nowadays, most systems and applications produce log records that are useful for security and monitoring purposes such as debugging programming errors, checking system status, and detecting configuration problems or even attacks. To this end, a log repository becomes necessary whereby logs can be accessed and visualized in a timely manner. This paper presents Loginson, a high-performance log centralization system for large-scale log collection and processing in large IT infrastructures. Besides log collection, Loginson provides high-level analytics through a visual interface for the purpose of troubleshooting critical incidents. We note that Loginson outperforms all of the other log centralization solutions by taking full advantage of the vertical scalability, and therefore decreasing Capital Expenditure (CAPEX) and Operating Expense (OPEX) costs for deployment scenarios with a huge volume of log data. [ABSTRACT FROM AUTHOR]

Reciprocation and interchange of grooming and support may emerge as a consequence of the socio-spatial structure of the group through which individuals interact with certain partners more frequently than with others. This is shown in a computational model of grouping, fighting, and grooming, called Groofiworld. In this case, no specific mechanism of exchange is needed, such as described in calculated reciprocity or emotional bookkeeping. One of the drawbacks of this model, GroofiWorld, however, is that it lacks social bonding, a factor that may play an important role in real societies of primates. To investigate the effect of social bonding on exchange relations, in the present study, we add 'social bonding' to the model 'GrooFiWorld.' In the new model, called 'FriendsWorld,' social bonds or 'friends' are defined as the top 25 % grooming partners and individuals are given a tendency to follow their friends. Note that they do not intend to reciprocate or interchange social services with friends. Results show that this mechanism of 'follow-your-friends,' not only increases social interactions among top grooming partners, but also strengthens the patterns of reciprocation and interchange. Our findings suggest that, in real primates, reciprocation and interchange may emerge as a side-effect of the social-spatial structure of the group and subsequently be strengthened by social bonding as represented in FriendsWorld. We give predictions that distinguish between the mechanism of 'follow-your-friends' and emotional bookkeeping. [ABSTRACT FROM AUTHOR]

S. Ramanujan introduced a technique, known as Ramanujan's Master Theorem, which provides an explicit expression for the Mellin transform of a function in terms of the analytic continuation of its Taylor coefficients. The history and proof of this result are reviewed, and a variety of applications is presented. Finally, a multi-dimensional extension of Ramanujan's Master Theorem is discussed. [ABSTRACT FROM AUTHOR]

The article describes the case of gastroesophageal junction leak following gastric bypass with serious sepsis and hemodynamic instability. A 56-year-old woman with morbid obesity, whose medical history included appendicectomy and severe obstructive sleep apnea syndrome, was admitted for gastric bypass. Particular focus is given to the surgical procedure that was initiated during laparoscopy. The placement of a self-expandable covered metal stent would have been the ideal procedure for the patient.

The article presents a research related to emotional modulation of memory. The researchers used an appetitive "trace" conditioning task in cats, in which a light and food are separated by a brief interval. Their findings show that amygdala activity elicited by an unexpected reward facilitates communication from perirhinal to entorhinal cortex. This suggests that the effect of amygdala activity on rhinal throughput is a plausible mechanism for facilitation of emotional memory by the amygdala.

A response by I. J. Arteaga-González to a letter to the editor about his article "A Revolutionary Design Change to Improve Stapler Safety" that was published in a previous issue is presented.