A perspective on cortical layering and layer-spanning neuronal elements

This review article addresses the function of the layers of the cerebral cortex. We develop the perspective that cortical layering needs to be understood in terms of its functional anatomy, i.e., the terminations of synaptic inputs on distinct cellular compartments and their effect on cortical activity. The cortex is a hierarchical structure in which feed forward and feedback pathways have a layer-specific termination pattern. We take the view that the influence of synaptic inputs arriving at different cortical layers can only be understood in terms of their complex interaction with cellular biophysics and the subsequent computation that occurs at the cellular level. We use high-resolution fMRI, which can resolve activity across layers, as a case study for implementing this approach by describing how cognitive events arising from the laminar distribution of inputs can be interpreted by taking into account the properties of neurons that span different layers. This perspective is based on recent advances in measuring subcellular activity in distinct feed-forward and feedback axons and in dendrites as they span across layers

Inhibitory Regulation of Dendritic Activity in vivo

The spatiotemporal control of neuronal excitability is fundamental to the inhibitory process. We now have a wealth of information about the active dendritic properties of cortical neurons including axonally generated sodium action potentials as well as local sodium spikelets generated in the dendrites, calcium plateau spikes, and NMDA spikes. All of these events have been shown to be highly modified by the spatiotemporal pattern of nearby inhibitory input which can drastically change the output firing mode of the neuron. This means that particular populations of interneurons embedded in the neocortical microcircuitry can more precisely control pyramidal cell output than has previously been thought. Furthermore, the output of any given neuron tends to feed back onto inhibitory circuits making the resultant network activity further dependent on inhibition. Network activity is therefore ultimately governed by the subcellular microcircuitry of the cortex and it is impossible to ignore the subcompartmentalization of inhibitory influence at the neuronal level in order to understand its effects at the network level. In this article, we summarize the inhibitory circuits that have been shown so far to act on specific dendritic compartments in vivo

How many people will carry on working from home? The answer will determine the future of central London

The instruction to work from home has had far-reaching effects on the UK capital. Tony Travers (LSE) sets out the challenges facing the centre of London, and Matthew Dillon and Laetitia Lucy (Arup) say it needs to become a sustainable, healthy and green urban centre, with a bigger residential population

Stabilization of Capacitated Matching Games

An edge-weighted, vertex-capacitated graph G is called stable if the value of a maximum-weight capacity-matching equals the value of a maximum-weight fractional capacity-matching. Stable graphs play a key role in characterizing the existence of stable solutions for popular combinatorial games that involve the structure of matchings in graphs, such as network bargaining games and cooperative matching games. The vertex-stabilizer problem asks to compute a minimum number of players to block (i.e., vertices of G to remove) in order to ensure stability for such games. The problem has been shown to be solvable in polynomial-time, for unit-capacity graphs. This stays true also if we impose the restriction that the set of players to block must not intersect with a given specified maximum matching of G. In this work, we investigate these algorithmic problems in the more general setting of arbitrary capacities. We show that the vertex-stabilizer problem with the additional restriction of avoiding a given maximum matching remains polynomial-time solvable. Differently, without this restriction, the vertex-stabilizer problem becomes NP-hard and even hard to approximate, in contrast to the unit-capacity case. Finally, in unit-capacity graphs there is an equivalence between the stability of a graph, existence of a stable solution for network bargaining games, and existence of a stable solution for cooperative matching games. We show that this equivalence does not extend to the capacitated case.Comment: 14 pages, 3 figure

Engineering multiple levels of specificity in an RNA viral vector

Synthetic molecular circuits could provide powerful therapeutic capabilities, but delivering them to specific cell types and controlling them remains challenging. An ideal "smart" viral delivery system would enable controlled release of viral vectors from "sender" cells, conditional entry into target cells based on cell-surface proteins, conditional replication specifically in target cells based on their intracellular protein content, and an evolutionarily robust system that allows viral elimination with drugs. Here, combining diverse technologies and components, including pseudotyping, engineered bridge proteins, degrons, and proteases, we demonstrate each of these control modes in a model system based on the rabies virus. This work shows how viral and protein engineering can enable delivery systems with multiple levels of control to maximize therapeutic specificity

Effect of heat stress on sow fertility and health

Abstract only availableHigh summer temperatures increase the chance that sow herds will be exposed to heat stress. Heat stress in sows causes a longer weaning to estrus interval, decreased farrowing rates and failure to maintain pregnancy. Conception rates of sows are also particularly lower in the summer than any other breeding season. When sows are bred in the summer, they farrow smaller litters and the average piglet weaning weight is significantly smaller than other seasons. The purpose of this research project is to directly test the effect of heat stress on sow health and fertility at the South Farm Complex in coordination with the Animal Science Research Center (ASRC) at the University of Missouri. Thermal temperatures were taken at the ear, shoulder, rump, tail and rectum for a group of sixteen sows on alternating days for two months. Sow body weight, loin muscle area (LMA) and backfat (BF) measurements were taken at three specific points during the study: the first day of the trial, the day the sows were moved into farrowing, and the day sows were moved into breeding .Once parturition occurred, information regarding the number, health and weight of each piglet was recorded. The results from this project will be compared to a previous heat stress study performed at the Brody Environmental Center within the ASRC. The study concludes that heat stress affects the sow's reproductive efficiency and health, but when and where the elevated temperatures specifically affect each sow and her offspring will be further discussed.F.B. Miller Undergraduate Research Program in Animal Science

Financial concern predicts deteriorations in mental and physical health among university students

Objective. The aim of the present study was to investigate whether students’ financial concerns predicted subsequent changes in their mental and physical health. In addition the opportunity was taken to test for reverse causality, by exploring whether initial levels of health predicted subsequent changes in financial concern. Design. The study employed a prospective correlational design. Main Outcome Measures. Undergraduate students at a British university (N = 337) completed measures of financial concern and health at two time points, approximately eight weeks apart. Results. Regression analyses indicated that experiencing greater financial concern at baseline was associated with subsequent deteriorations in health on the following outcomes: role limitation due to physical health problems, role limitation due to emotional problems, social functioning, mental health, general health perception and change in health. By contrast, there was no evidence that initial health influenced subsequent changes in financial concern. Conclusion. Findings suggest that financial concern might adversely impact mental and physical health outcomes in student populations