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Introduction: Recent work on bats flying over long distances has revealed that single hippocampal cells have multiple place fields of different sizes. At the network level, a multi-scale, multi-field place cell code outperforms classical single-scale, single-field place codes, yet the performance boundaries of such a code remain an open question. In particular, it is unknown how general multi- field codes compare to a highly regular grid code, in which cells form distinct modules with different scales. Methods: In this work, we address the coding properties of theoretical spatial coding models with rigorous analyses of comprehensive simulations. Starting fromamulti-scale,multi-field network, we performed evolutionary optimization. The resulting multi-field networks sometimes retained the multi-scale property at the single-cell level but most often converged to a single scale, with all place fields in a given cell having the same size. We compared the results against a single-scale single-field code and a one-dimensional grid code, focusing on two main characteristics: the performance of the code itself and the dynamics of the network generating it. Results: Our simulation experiments revealed that, under normal conditions, a regular grid code outperforms all other codes with respect to decoding accuracy, achieving a given precision with fewer neurons and fields. In contrast, multi- field codes are more robust against noise and lesions, such as random drop- out of neurons, given that the significantly higher number of fields provides redundancy. Contrary to our expectations, the network dynamics of all models, from the original multi-scale models before optimization to the multi-field models that resulted from optimization, did not maintain activity bumps at their original locations when a position-specific external input was removed. Discussion: Optimizedmulti-field codes appear to strike a compromise between a place code and a grid code that reflects a trade-off between accurate positional encoding and robustness. Surprisingly, the recurrent neural network models we implemented and optimized for either multi- or single-scale, multi-field codes did not intrinsically produce a persistent "memory" of attractor states. These models, therefore, were not continuous attractor networks. [ABSTRACT FROM AUTHOR]

Abstract Background Lifestyle recommendations for cancer survivors are warranted to improve survival. In this study, we aimed to examine the association of total physical activity, different types of physical activity, hours of sleeping at day and night, and hours spent watching television (TV) with all-cause mortality in long-term colorectal cancer (CRC) survivors. Methods We assessed physical activity in 1376 CRC survivors (44% women; median age, 69 years) at median 6 years after CRC diagnosis using a validated questionnaire. Multivariable-adjusted Cox regression models were used to estimate hazard ratios (HRs) for all-cause mortality according to categories of physical activities, sleep duration, and TV watching. Results During a median follow-up time of 7 years, 200 participants had died. Higher total physical activity was significantly associated with lower all-cause mortality (HR: 0.53; 95% CI: 0.36–0.80, 4th vs. 1st quartile). Specifically, sports, walking, and gardening showed a significant inverse association with all-cause mortality (HR: 0.34; 95% CI: 0.20–0.59, HR: 0.65; 95% CI: 0.43–1.00, and HR: 0.62; 95% CI: 0.42–0.91, respectively for highest versus lowest category). Individuals with ≥2 h of sleep during the day had a significantly increased risk of all-cause mortality compared to individuals with no sleep at day (HR: 2.22; 95% CI: 1.43–3.44). TV viewing of ≥4 h per day displayed a significant 45% (95% CI: 1.02–2.06) higher risk of dying compared to ≤2 h per day of watching TV. Conclusions Physical activity was inversely related to all-cause mortality; specific activity types might be primarily responsible for this association. More hours of sleep during the day and a higher amount of TV viewing were each associated with higher all-cause mortality. Based on available evidence, it is reasonable to recommend CRC survivors to engage in regular physical activity.

J. Butler hob mit S. Freud die Identifizierungen des Kindes hervor (Psyche der Macht, 2001), wobei sie geschlechtliche Identität als Produkt einer melancholischen Einverleibung der frühen Anderen sichtbar machte. Was aber, wenn man nicht die ödipalen Identifizierungen, sondern das Begehren als bestimmenden Faktor der Vergeschlechtlichung erwägt? Dieser Frage soll mit J. Lacan, der das Begehren als ein strukturelles Vermögen begriff, nachgegangen werden: Dieses entsteht, sobald die mütterliche Bezugsperson durch Symbole substituiert wird, was dem Kind später erlaubt, den inzestuös verbotenen Anderen durch Objekte zu ersetzen. Dieser zweizeitige Prozess rückt die Vergeschlechtlichung in die Nähe zur Sublimierung, wobei Geschlechtliches als eine besondere Form der Sublimierung verstanden werden kann. Dabei erweist sich das Begehren nachhaltiger als die Identifizierungen, da es das Subjekt – jenseits der gefährlichen melancholischen Verstrickungen – zu Drittem in das Soziale führt. Eine derart über das Begehren aufgefasste Geschlechtlichkeit hat nicht zuletzt auch gesellschaftspolitische Relevanz, da Identitäres nicht als zentraler Angelpunkt der Subjektformation aufgefasst werden muss: Geschlechterpolitik wäre damit nicht nur Angelegenheit gleicher Identifikationsgruppen, sondern einer stets auf das Neue herzustellenden Gemeinschaft in Bezug auf den geteilten Wunsch nach lebbarem Begehren in unserer Gesellschaft.

Planktonic foraminifera preserved in marine sediments archive the physical and chemical conditions under which they built their shells. To interpret the paleoceanographic information contained in fossil foraminifera, the recorded proxy signals have to be attributed to the habitat and life cycle characteristics of individual species. Much of our knowledge on habitat depth is based on indirect methods, which reconstruct the depth at which the largest portion of the shell has been calcified. However, habitat depth can be best studied by direct observations in stratified plankton nets. Here we present a synthesis of living planktonic foraminifera abundance data in vertically resolved plankton net hauls taken in the eastern North Atlantic during 12 oceanographic campaigns between 1995 and 2012. Live (cytoplasm-bearing) specimens were counted for each depth interval and the vertical habitat at each station was expressed as average living depth (ALD). This allows us to differentiate species showing an ALD consistently in the upper 100 m (e.g., Globigerinoides ruber white and pink), indicating a shallow habitat; species occurring from the surface to the subsurface (e.g., Globigerina bulloides, Globorotalia inflata, Globorotalia truncatulinoides); and species inhabiting the subsurface (e.g., Globorotalia scitula and Globorotalia hirsuta). For 17 species with variable ALD, we assessed whether their depth habitat at a given station could be predicted by mixed layer (ML) depth, temperature in the ML and chlorophyll a concentration in the ML. The influence of seasonal and lunar cycle on the depth habitat was also tested using periodic regression. In 11 out of the 17 tested species, ALD variation appears to have a predictable component. All of the tested parameters were significant in at least one case, with both seasonal and lunar cyclicity as well as the environmental parameters explaining up to > 50 % of the variance. Thus, G. truncatulinoides, G. hirsuta and G. scitula appear to descend in the water column towards the summer, whereas populations of Trilobatus sacculifer appear to descend in the water column towards the new moon. In all other species, properties of the mixed layer explained more of the observed variance than the periodic models. Chlorophyll a concentration seems least important for ALD, whilst shoaling of the habitat with deepening of the ML is observed most frequently. We observe both shoaling and deepening of species habitat with increasing temperature. Further, we observe that temperature and seawater density at the depth of the ALD were not equally variable among the studied species, and their variability showed no consistent relationship with depth habitat. According to our results, depth habitat of individual species changes in response to different environmental and ontogenetic factors and consequently planktonic foraminifera exhibit not only species-specific mean habitat depths but also species-specific changes in habitat depth.

Historically, Silesia has been at the centre of the Polish coal industry for many years and thus has experienced poorer air quality compared to other voivodeships. However, in recent years strong economic transformation in the area has led to a considerable reduction in coal production. This study aimed to assess the variability of global solar radiation at selected stations within the Silesian voivodeship, in order to re-evaluate the resources of renewable solar energy during the period 1994–2013. The theoretical potential of solar radiation was calculated based on a three-dimensional terrain model. The data on global solar radiation from 13 stations within the Silesia region, covering the period 1994–2013, were obtained from the Regional Inspectorate of Environmental Protection in Katowice. The most favourable conditions for the use of solar energy were found at the cities Sosnowiec and Cieszyn. The largest increase in global radiation over the research period was observed in Zabrze. The average annual global radiation ranged between 600–1300 kWh·m−2. Digital Elevation Models (DEM) for selected districts of the Silesia region were used to calculate the theoretical potential of global solar radiation. The highest theoretical potential of global radiation was found in the district of Cieszyn, located at the highest altitude.

Book Review

Evaluating the health status of marine ecosystems becomes ever increasingly important especially against the backdrop of rising pressures from human activities. This is true especially for coastal seas such as the Baltic Sea that is surrounded by highly industrialized countries. Nutrients and pollutants such as nitrate and hydrogen sulfide, which have a major impact on ecosystem functioning, are two of several key environmental indicators for assessing the status of natural waters, and therefore of considerable interest. The frequency and the spatial coverage of the nitrate and hydrogen sulfide measurements are currently limited by the cost of the laboratory analysis and personnel. Optical in situ sensors can help to overcome this challenge by allowing reagentless and fast detection of dissolved chemical species. A chemical-free optical sensor has been used for direct and simultaneous measurements of both key parameters, and the results were compared with traditional methods. The data were collected during an observational program conducted in the Baltic Sea in February 2018. We used the OPUS UV spectral sensor, which was deployed for the first time in coastal waters, in combination with a deep-sea telemetry system to enable near-real time measurements during CTD profiling. Data processing was carried out using a multiple linear regression procedure. Measurements from both OPUS and on-board analysis were in good agreement. The results showed, that in situ UV-VIS spectrophotometry provides the capability to determine the concentration distributions of nitrate and hydrogen sulfide in the brackish waters of the Baltic Sea.

Abstract Background Trypanosoma rangeli is a protozoan that infects a variety of mammalian hosts, including humans. Its main insect vector is Rhodnius prolixus and is found in several Latin American countries. The R. prolixus vector competence depends on the T. rangeli strain and the molecular interactions, as well as the insect’s immune responses in the gut and haemocoel. This work focuses on the modulation of the humoral immune responses of the midgut of R. prolixus infected with T. rangeli Macias strain, considering the influence of the parasite on the intestinal microbiota. Methods The population density of T. rangeli Macias strain was analysed in different R. prolixus midgut compartments in long and short-term experiments. Cultivable and non-cultivable midgut bacteria were investigated by colony forming unit (CFU) assays and by 454 pyrosequencing of the 16S rRNA gene, respectively. The modulation of R. prolixus immune responses was studied by analysis of the antimicrobial activity in vitro against different bacteria using turbidimetric tests, the abundance of mRNAs encoding antimicrobial peptides (AMPs) defensin (DefA, DefB, DefC), prolixicin (Prol) and lysozymes (LysA, LysB) by RT-PCR and analysis of the phenoloxidase (PO) activity. Results Our results showed that T. rangeli successfully colonized R. prolixus midgut altering the microbiota population and the immune responses as follows: 1 - reduced cultivable midgut bacteria; 2 - decreased the number of sequences of the Enterococcaceae but increased those of the Burkholderiaceae family; the families Nocardiaceae, Enterobacteriaceae and Mycobacteriaceae encountered in control and infected insects remained the same; 3 - enhanced midgut antibacterial activities against Serratia marcescens and Staphylococcus aureus; 4 - down-regulated LysB and Prol mRNA levels; altered DefB, DefC and LysA depending on the infection (short and long-term); 5 - decreased PO activity. Conclusion Our findings suggest that T. rangeli Macias strain modulates R. prolixus immune system and modifies the natural microbiota composition.