Scaling Approach to the Phase Diagram of Quantum Hall Systems

We present a simple classification of the different liquid and solid phases of quantum Hall systems in the limit where the Coulomb interaction between the electrons is significant, i.e. away from integral filling factors. This classification, and a criterion for the validity of the mean-field approximation in the charge-density-wave phase, is based on scaling arguments concerning the effective interaction potential of electrons restricted to an arbitrary Landau level. Finite-temperature effects are investigated within the same formalism, and a good agreement with recent experiments is obtained.Comment: 4 pages, 3 figures; to be published in Europhys. Lett.; new version contains more detailed description of finite-temperature effect

Physiological constrains on Sverdrup's Critical-Depth-Hypothesis: the influences of dark respiration and sinking

Discussions on the controls initiating the onset of the phytoplankton spring bloom in particular in the North Atlantic have since Sverdrup been dominated by the role of physical and biological drivers. Undoubtedly, these drivers play an important role in phytoplankton dynamics and thus the onset of the spring bloom. However, they neglect the cells ability to modify vital rates in response to changes in the external environment. In this study, we use a non-hydrostatic convection model coupled to an Individual-Based-Model to simulate changes phytoplankton cells during the transition from winter conditions as driven by convective mixing, and the onset of thermal stratification resulting in the spring bloom. The comparison between a simulation using a standard fixed rate approach in line with the original Sverdrup hypothesis and a simulation parameterized to include variable respiration and sinking rates showed that the latter approach was able to capture the observed phytoplankton concentration during deep convective mixing, the timing and magnitude of the spring bloom as well as simulating realistic physiological rates. In contrast, the model employing fixed rate parameterizations could only replicate field observations when employing unrealistic parameter values. These results highlight the necessity to consider not only the physical and biological external controls determining phytoplankton dynamics but also the cells ability to modify critical physiological rates in response to external constraints. Understanding these adaptive qualities will be of increasing importance in the future as species assemblages and physical controls change with changing climate

How to not induce SNAs: The insufficiency of directional force.

People respond faster to smaller numbers in their left space and to larger numbers in their right space. Here we argue that movements in space contribute to the formation of spatial-numerical associations (SNAs). We studied the impact of continuous isometric forces along the horizontal or vertical cardinal axes on SNAs while participants performed random number production and arithmetic verification tasks. Our results suggest that such isometric directional force do not suffice to induce SNAs. [Abstract copyright: Copyright: © 2023 Michirev et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Context Effects in Embodied Lexical-Semantic Processing

The embodied view of language comprehension proposes that the meaning of words is grounded in perception and action rather than represented in abstract amodal symbols. Support for embodied theories of language processing comes from behavioral studies showing that understanding a sentence about an action can modulate congruent and incongruent physical responses, suggesting motor involvement during comprehension of sentences referring to bodily movement. Additionally, several neuroimaging studies have provided evidence that comprehending single words denoting manipulable objects elicits specific responses in the neural motor system. An interesting question that remains is whether action semantic knowledge is directly activated as motor simulations in the brain, or rather modulated by the semantic context in which action words are encountered. In the current paper we investigated the nature of conceptual representations using a go/no-go lexical decision task. Specifically, target words were either presented in a semantic context that emphasized dominant action features (features related to the functional use of an object) or non-dominant action features. The response latencies in a lexical decision task reveal that participants were faster to respond to words denoting objects for which the functional use was congruent with the prepared movement. This facilitation effect, however, was only apparent when the semantic context emphasized corresponding motor properties. These findings suggest that conceptual processing is a context-dependent process that incorporates motor-related knowledge in a flexible manner

Humoral response to a 13-valent pneumococcal conjugate vaccine in kidney transplant recipients

Background: Vaccination against S. pneumoniae is recommended by national guidelines. Moderate immunogenicity of the 13-valent pneumococcal conjugate vaccine (PCV13) has been reported in adult kidney transplant recipients (KTR). This study further defines the immunogenicity of PCV13 in this cohort. Methods: 49 KTR were immunized with PCV13. A validated opsonophagocytic killing assay (OPA), a global anti-pneumococcal capsular polysaccharide (anti-PCP) IgG, IgG2, IgM and IgA ELISA, and - for selected patients - a serotype specific anti-PCP WHO reference ELISA were performed pre-vaccination and at month 1 and 12 post-vaccination. Results: Geometric mean OPA titers increased significantly for 13/13 serotypes at month 1 and for 10/13 serotypes at month 12 post-vaccination. Vaccine response defined as an OPA titer ≥1:8 was reached in 9/13 serotypes (median). 53% reached the vaccine response criteria at month 1 and 45% at month 12. At month 1 after vaccination, the median OPA titer in an age-group matched healthy reference population was 5- to 10-fold higher than in KTR. OPA titers correlated strongly with results to the global and serotype specific anti-PCP IgG ELISA. Lower OPA titers significantly (p < 0.05) correlated with albuminuria, an interval between vaccination and transplantation <12 months, age and treatment with mycophenolate mofetil. Global IgG, IgG2, IgM and IgA, as well as serotype specific anti-PCP antibody concentrations (12/13 serotypes) increased significantly at month 1 and 12 post-vaccination. Conclusions: Kidney transplant recipients show a significant humoral response after vaccination with PCV13. Functional antibody response exists, but is not as vigorous as in healthy adults

Reaching out to the other side: Formal-linguistics-based SLA and Socio-SLA

Generative linguistics has long been concerned with the linguistic competence of the “ideal speaker-listener, in a completely homogeneous speech-community, who knows its language perfectly” (Chomsky 1965: 3). Research in formal-linguistics-based second language acquisition takes as its starting point the second language (L2) speaker's underlying mental representation. Here the factors of interest are influence of the learner's native language and, in generative SLA, the operation of innate linguistic mechanisms (Universal Grammar). Similar to methodology in formal syntax, lxSLA adopts techniques such as grammaticality judgment, comprehension and perception tasks supplementing spontaneously produced oral data. While there may be individual differences in oral production, tasks that tap learners' mental representations reveal commonalities across learners from a given native language background with the same amount/ type of exposure and age of initial L2 exposure. When it comes to phonology, age has long been a central factor with numerous comparative studies showing younger learners far outperforming older learners (see Piske et al. 2001). This paper discusses a case of possible non-acquisition by L2 children who had had considerable exposure to the L2. Children's non-acquisition is only apparent, and this allows us to consider the value of lxSLA methodology on the one hand, and and raises issues about what might be lacking in the current socio-SLA paradigm, on the other. We argue that only when we return to the cooperation that marked its birth in the 1960s will we have a comprehensive picture of SLA

Anomalous diffusion and asymmetric tempering memory in neutrophil chemotaxis.

The motility of neutrophils and their ability to sense and to react to chemoattractants in their environment are of central importance for the innate immunity. Neutrophils are guided towards sites of inflammation following the activation of G-protein coupled chemoattractant receptors such as CXCR2 whose signaling strongly depends on the activity of Ca2+ permeable TRPC6 channels. It is the aim of this study to analyze data sets obtained in vitro (murine neutrophils) and in vivo (zebrafish neutrophils) with a stochastic mathematical model to gain deeper insight into the underlying mechanisms. The model is based on the analysis of trajectories of individual neutrophils. Bayesian data analysis, including the covariances of positions for fractional Brownian motion as well as for exponentially and power-law tempered model variants, allows the estimation of parameters and model selection. Our model-based analysis reveals that wildtype neutrophils show pure superdiffusive fractional Brownian motion. This so-called anomalous dynamics is characterized by temporal long-range correlations for the movement into the direction of the chemotactic CXCL1 gradient. Pure superdiffusion is absent vertically to this gradient. This points to an asymmetric 'memory' of the migratory machinery, which is found both in vitro and in vivo. CXCR2 blockade and TRPC6-knockout cause tempering of temporal correlations in the chemotactic gradient. This can be interpreted as a progressive loss of memory, which leads to a marked reduction of chemotaxis and search efficiency of neutrophils. In summary, our findings indicate that spatially differential regulation of anomalous dynamics appears to play a central role in guiding efficient chemotactic behavior

Identifying content to improve risk assessment communications within the Risk Profile: Literature reviews and focus groups with expert and non-expert stakeholders

Objective: To improve consumer decision making, the results of risk assessments on food, feed, consumer products or chemicals need to be communicated not only to experts but also to non-expert audiences. The present study draws on evidence from literature reviews and focus groups with diverse stakeholders to identify content to integrate into an existing risk assessment communication (Risk Profile). Methods: A combination of rapid literature reviews and focus groups with experts (risk assessors (n = 15), risk managers (n = 8)), and non-experts (general public (n = 18)) were used to identify content and strategies for including information about risk assessment results in the “Risk Profile” from the German Federal Institute for Risk Assessment. Feedback from initial focus groups was used to develop communication prototypes that informed subsequent feedback rounds in an iterative process. A final prototype was validated in usability tests with experts. Results: Focus group feedback and suggestions from risk assessors were largely in line with findings from the literature. Risk managers and lay persons offered similar suggestions on how to improve the existing communication of risk assessment results (e.g., including more explanatory detail, reporting probabilities for individual health impairments, and specifying risks for subgroups in additional sections). Risk managers found information about quality of evidence important to communicate, whereas people from the general public found this information less relevant. Participants from lower educational backgrounds had difficulties understanding the purpose of risk assessments. User tests found that the final prototype was appropriate and feasible to implement by risk assessors. Conclusion: An iterative and evidence-based process was used to develop content to improve the communication of risk assessments to the general public while being feasible to use by risk assessors. Remaining challenges include how to communicate dose-response relationships and standardise quality of evidence ratings across disciplines.Peer Reviewe