Recognition memory performance can be estimated based on brain activation networks

Recognition memory is an essential ability for functioning in everyday life. Establishing robust brain networks linked to recognition memory performance can help to understand the neural basis of recognition memory itself and the interindividual differences in recognition memory performance.; We analysed behavioural and whole-brain fMRI data from 1'410 healthy young adults during the testing phase of a picture-recognition task. Using independent component analysis (ICA), we decomposed the fMRI contrast for previously seen vs. new (old-new) pictures into networks of brain activity. This was done in two independent samples (training sample: N = 645, replication sample: N = 665). Next, we investigated the relationship between the identified brain networks and interindividual differences in recognition memory performance by conducting a prediction analysis. We estimated the prediction accuracy in a third independent sample (test sample: N = 100).; We identified 12 robust and replicable brain networks using two independent samples. Based on the activity of those networks we could successfully estimate interindividual differences in recognition memory performance with high accuracy in a third independent sample (r = 0.5, p = 1.29 × 10; -07; ).; Given the robustness of the ICA decomposition as well as the high prediction estimate, the identified brain networks may be considered as potential biomarkers of recognition memory performance in healthy young adults and can be further investigated in the context of health and disease

Selective and highly efficient dye scavenging by a pH-responsive molecular hydrogelator

A structurally simple low molecular weight hydrogelator derived from isophthalic acid forms robust pH-responsive hydrogels capable of highly efficient and selective dye adsorption

Infrared conductivity of a one-dimensional charge-ordered state: quantum lattice effects

The optical properties of the charge-ordering ($CO$) phase of the one-dimensional (1D) half-filled spinless Holstein model are derived at zero temperature within a well-known variational approach improved including second-order lattice fluctuations. Within the $CO$ phase, the static lattice distortions give rise to the optical interband gap, that broadens as the strength of the electron-phonon ($el-ph$) interaction increases. The lattice fluctuation effects induce a long subgap tail in the infrared conductivity and a wide band above the gap energy. The first term is due to the multi-phonon emission by the charge carriers, the second to the interband transitions accompanied by the multi-phonon scattering. The results show a good agreement with experimental spectra.Comment: 5 figure

Dynamical Properties of small Polarons

On the basis of the two-site polaron problem, which we solve by exact diagonalization, we analyse the spectral properties of polaronic systems in view of discerning localized from itinerant polarons and bound polaron pairs from an ensemble of single polarons. The corresponding experimental techniques for that concern photoemission and inverse photoemission spectroscopy. The evolution of the density of states as a function of concentration of charge carriers and strength of the electron-phonon interaction clearly shows the opening up of a gap between single polaronic and bi-polaronic states, in analogy to the Hubbard problem for strongly correlated electron systems. The crossover regime between adiabatic and anti-adiabatic small polarons is triggered by two characteristic time scales: the renormalized electron hopping rate and the renormalized vibrational frequency becoming equal. This crossover regime is then characterized by temporarily alternating self- localization and delocalization of the charge carriers which is accompanied by phase slips in the charge and molecular deformation oscillations and ultimately leads to a dephasing between these two dynamical components of the polaron problem. We visualize these features by a study of the temporal evolution of the charge redistribution and the change in molecular deformations. The spectral and dynamical properties of polarons discussed here are beyond the applicability of the standard Lang Firsov approach to the polaron problem.Comment: 31 pages and 23 figs.(eps), accepted in the Phys. Rev.

Переходная зона между шельфом и континентальным склоном северной части Чёрного моря. Ландшафтный подход

На основе данных, полученных с применением обитаемых подводных аппаратов, рассмотрена проблема положения бровки шельфа как важной структурно фациальной границы морского бассейна. Описана ландшафтная фациальная зональность в диапазоне глубин 70–220 м в северной части Черного моря. Выявлено, что смена фаций в переходной зоне между шельфом и материковым склоном от бровки шельфа до глубины около 200 м находится в тесной связи с усилением гипоксии до полной аноксии.На основі даних, отриманих із застосуванням підводних апаратів, розглянуто проблему положення бровки шельфу як важливої структурно фаціальної межі морського басейну. Описано ландшафтну фаціальну зональність в діапазоні глибин 70–20 м у північній частині Чорного моря. Виявлено, що зміна фацій у перехідній зоні між шельфом і материковим схилом від бровки шельфу до глибини близько 200 м тісно пов’язана із збільшенням гіпоксії до повної аноксії.The problem of continental shelf break position as an important structural – facial marine basin boundary discussed on the basis of manned submersibles’ data. The range and setting of Northern Black Sea facial zones in the depths interval 70 220m are described. It’s found that the facial changes are related closely with hypoxia increasing to complete anoxia from the shelf break to the depth of about 200 m

On Deformations of n-Lie algebras

The aim of this paper is to review the deformation theory of $n$-Lie algebras. We summarize the 1-parameter formal deformation theory and provide a generalized approach using any unital commutative associative algebra as a deformation base. Moreover, we discuss degenerations and quantization of $n$-Lie algebras.Comment: Proceeding of the conference Dakar's Workshop in honor of Pr Amin Kaidi. arXiv admin note: text overlap with arXiv:hep-th/9602016 by other author

Association between birth weight and visceral fat in adults

Background: Several studies reported inverse associations between birth weight and central adiposity in adults. However, few studies investigated the contributions of different abdominal fat compartments. Objective: We examined associations between birth weight and adult visceral and subcutaneous abdominal fat in the population-based Fenland study. Design: A total of 1092 adults (437 men and 655 women) aged 3055 y had available data on reported birth weight, standard anthropometric measures, and visceral and subcutaneous abdominal fat estimated by ultrasound. In a subgroup (n = 766), dual-energy X-ray absorptiometry assessment of total abdominal fat was performed. Linear regression models were used to analyze relations between birth weight and the various fat variables adjusted for sex, age, education, smoking, and body mass index (BMI). Results: After adjustment for adult BMI, there was an inverse association between birth weight and total abdominal fat [B (partial regression coefficient expressed as SD/1-kg change in birth weight) = -0.09, P = 0.002] and visceral fat (B = -0.07, P = 0.01) but not between birth weight and subcutaneous abdominal fat (B = -0.01, P = 0.3). Tests for interaction showed that adult BMI modified the association between birth weight and visceral fat (P for interaction = 0.01). In stratified analysis, the association between birth weight and visceral fat was apparent only in individuals with the highest BMI tertile (B = -0.08, P = 0.04). Conclusions: The inverse association between birth weight and adult abdominal fat appeared to be specific to visceral fat. However, associations with birth weight were apparent only after adjustment for adult BMI. Therefore, we suggest that rapid postnatal weight gain, rather than birth weight alone, leads to increased visceral fat. Am J Clin Nutr 2010; 92: 347-52

Human cerebellum and corticocerebellar connections involved in emotional memory enhancement

Emotional information is better remembered than neutral information. Extensive evidence indicates that the amygdala and its interactions with other cerebral regions play an important role in the memory-enhancing effect of emotional arousal. While the cerebellum has been found to be involved in fear conditioning, its role in emotional enhancement of episodic memory is less clear. To address this issue, we used a whole-brain functional MRI approach in 1,418 healthy participants. First, we identified clusters significantly activated during enhanced memory encoding of negative and positive emotional pictures. In addition to the well-known emotional memory-related cerebral regions, we identified a cluster in the cerebellum. We then used dynamic causal modeling and identified several cerebellar connections with increased connection strength corresponding to enhanced emotional memory, including one to a cluster covering the amygdala and hippocampus, and bidirectional connections with a cluster covering the anterior cingulate cortex. The present findings indicate that the cerebellum is an integral part of a network involved in emotional enhancement of episodic memory

Space-time versus particle-hole symmetry in quantum Enskog equations

The non-local scattering-in and -out integrals of the Enskog equation have reversed displacements of colliding particles reflecting that the -in and -out processes are conjugated by the space and time inversions. Generalisations of the Enskog equation to Fermi liquid systems are hindered by a request of the particle-hole symmetry which contradicts the reversed displacements. We resolve this problem with the help of the optical theorem. It is found that space-time and particle-hole symmetry can only be fulfilled simultaneously for the Bruckner-type of internal Pauli-blocking while the Feynman-Galitskii form allows only for particle-hole symmetry but not for space-time symmetry due to a stimulated emission of Bosons

Down syndrome-recent progress and future prospects

Down syndrome (DS) is caused by trisomy of chromosome 21 (Hsa21) and is associated with a number of deleterious phenotypes, including learning disability, heart defects, early-onset Alzheimer's disease and childhood leukaemia. Individuals with DS are affected by these phenotypes to a variable extent; understanding the cause of this variation is a key challenge. Here, we review recent research progress in DS, both in patients and relevant animal models. In particular, we highlight exciting advances in therapy to improve cognitive function in people with DS and the significant developments in understanding the gene content of Hsa21. Moreover, we discuss future research directions in light of new technologies. In particular, the use of chromosome engineering to generate new trisomic mouse models and large-scale studies of genotype-phenotype relationships in patients are likely to significantly contribute to the future understanding of DS