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When remembering the past, we typically recall ‘events’ that are bounded in time and space. However, as we navigate our environment our senses receive a continuous stream of information. How do we create discrete long-term episodic memories from continuous input? Although previous research has provided evidence for a role of spatial boundaries in the online segmentation of our sensory experience within working memory, it is not known how this segmentation contributes to subsequent long-term episodic memory. Here we show that the presence of a spatial boundary at encoding (a doorway between two rooms) impairs participants’ later ability to remember the order that objects were presented in. A sequence of two objects presented in the same room in a virtual reality environment is more accurately remembered than a sequence of two objects presented in adjoining rooms. The results are captured by a simple model in which items are associated to a context representation that changes gradually over time, and changes more rapidly when crossing a spatial boundary. We therefore provide the first evidence that the structure of long-term episodic memory is shaped by the presence of a spatial boundary and provide constraints on the nature of the interaction between working memory and long-term memory.

This policy brief contributes to assessing the economic and social viability of Tanzania’s Wildlife Management Areas (WMAs) through preliminary findings by the ‘Poverty and ecosystem Impacts of Tanzania’s Wildlife Management Areas’ (PIMA) project, focusing on benefits, costs, and their distribution between State, community and household

Lowered extracellular pH in a variety of tissues is associated with increased tissue destruction and initiation of inflammatory processes. Although the acid-sensing receptors described previously are ion channels, we describe a G protein-coupled proton-sensitive receptor that stimulates Ca2+ release from intracellular stores in a tumor-derived synoviocyte cell line (SW982) and in primary cultures of human synovial cells from patients with inflammatory arthropathies. We established a link between proton-dependent receptor activation and intracellular Ca2+ mobilization by demonstrating 1) dependence on the integrity of the intracellular Ca2+ store, 2) independence from extracellular Ca2+, and 3) proton-induced production of inositol phosphate and 4) by abolishing the effect with GTPase inhibitors. We propose that this G protein-coupled acid-sensing receptor linked to intracellular Ca2+ mobilization in synoviocytes can contribute to downstream inflammatory and cellular proliferative processes in synovial fibroblasts. The acid-sensing receptor has distinct characteristics as a metabotropic G protein-coupled receptor on human synoviocytes in this emerging new class of receptors.

Receptors located in the facial pit organ of certain species of snake signal the presence of prey. Infrared radiation is an effective stimulus suggesting that these receptors may be low-threshold temperature receptors. We recorded from the nerve innervating the pit organ of snakes belonging to the family of Crotalinae while stimulating the receptive area with well-defined optical stimuli. The objective was to determine the sensitivity of these receptors to a wide range (0.400–10.6 μm) of optical stimuli to determine if a temperature-sensitive or photosensitive protein initiated signal transduction. We found that receptors in the pit organ exhibited a unique broad response to a wide range of electromagnetic radiation ranging from the near UV to the infrared. The spectral tuning of these receptors parallels closely the absorption spectra of water and oxyhemoglobin, the predominant chromophore in tissue. Our results support the hypothesis that these are receptors activated by minute temperature changes induced by direct absorption of optical radiation in the thin pit organ membrane.

Memory retrieval is believed to involve a disparate network of areas, including medial prefrontal and medial temporal cortices, but the mechanisms underlying their coordination remain elusive. One suggestion is that oscillatory coherence mediates inter-regional communication, implicating theta phase and theta-gamma phase-amplitude coupling in mnemonic function across species. To examine this hypothesis, we used non-invasive whole-head magnetoencephalography (MEG) as participants retrieved the location of objects encountered within a virtual environment. We demonstrate that, when participants are cued with the image of an object whose location they must subsequently navigate to, there is a significant increase in 4–8 Hz theta power in medial prefrontal cortex (mPFC), and the phase of this oscillation is coupled both with ongoing theta phase in the medial temporal lobe (MTL) and perceptually induced 65–85 Hz gamma amplitude in medial parietal cortex. These results suggest that theta phase coupling between mPFC and MTL and theta-gamma phase-amplitude coupling between mPFC and neocortical regions may play a role in human spatial memory retrieval. © 2014 The Authors. Hippocampus Published by Wiley Periodicals, Inc.

The anaesthetic management of a 38-year-old woman having excision of a meningioma involving the superior sagittal sinus is described. The procedure was performed using low flow moderate hypothermic cardiopulmonary bypass with central cannulation. Relevant literature is reviewed.

Gastrin-releasing peptide (GRP) and its amphibian homolog, bombesin, are potent secretogogues in mammals. We determined the roles of intracellular free Ca(2+) ([Ca(2+)](i)), protein kinase C (PKC), and mitogen-activated protein kinases (MAPK) in GRP receptor (GRP-R)-regulated secretion. Bombesin induced either [Ca(2+)](i) oscillations or a biphasic elevation in [Ca(2+)](i). The biphasic response was associated with peptide secretion. Receptor-activated secretion was blocked by removal of extracellular Ca(2+), by chelation of [Ca(2+)](i), and by treatment with inhibitors of phospholipase C, conventional PKC isozymes, and MAPK kinase (MEK). Agonist-induced increases in [Ca(2+)](i) were also inhibited by dominant negative MEK-1 and the MEK inhibitor, PD89059, but not by an inhibitor of PKC. Direct activation of PKC by a phorbol ester activated MAPK and stimulated peptide secretion without a concomitant increase in [Ca(2+)](i). Inhibition of MEK blocked both bombesin- and phorbol 12-myristate 13-acetate-induced secretion. GRP-R-regulated secretion is initiated by an increase in [Ca(2+)](i); however, elevated [Ca(2+)](i) is insufficient to stimulate secretion in the absence of activation of PKC and the downstream MEK/MAPK pathways. We demonstrated that the activity of MEK is important for maintaining elevated [Ca(2+)](i) levels induced by GRP-R activation, suggesting that MEK may affect receptor-regulated secretion by modulating the activity of Ca(2+)-sensitive PKC.

The cognitive processes supporting spatial navigation are considered in the context of a patient (CF) with possible very early Alzheimer's disease who presents with topographical disorientation. Her verbal memory and her recognition memory for unknown buildings, landmarks and outdoor scenes was intact, although she showed an impairment in face processing. By contrast, her navigational ability, quantitatively assessed within a small virtual reality (VR) town, was significantly impaired. Interestingly, she showed a selective impairment in a VR object-location memory test whenever her viewpoint was shifted between presentation and test, but not when tested from the same viewpoint. We suggest that a specific impairment in locating objects relative to the environment rather than relative to the perceived viewpoint (i.e. allocentric rather than egocentric spatial memory) underlies her topographical disorientation. We discuss the likely neural bases of this deficit in the light of related studies in humans and animals, focusing on the hippocampus and related areas. The specificity of our test indicates a new way of assessing topographical disorientation, with possible application to the assessment of progressive dementias such as Alzheimer's disease.

This study examines the impact of research and development (R&D)-specific factors in determining the likelihood of small- and medium-sized enterprises (SMEs) from developed countries to be attractive partners vis-Ã -vis forming alliances with SMEs from large emerging economies (LEEs). This study is founded on the knowledge-accessing theory of alliance formation, which emphasises the higher efficiency gains of knowledge application as opposed to knowledge generation. We extend this theory to SMEs on the basis that smaller firms, because of their resources constraints and drive to survive, are likely to use alliances to access external knowledge bases leading to new product development (NPD) opportunities because of the low feasibility of acquiring knowledge. As a mix of complex knowledge is necessary to develop most modern products and services, SMEs are also likely to adopt a more flexible operational approach and to accept compromises to forge knowledge-accessing alliances. We illustrate this theoretical development using primary data collected from British and German biotechnology SMEs, declaring the intention prospectively to form alliances with their counterparts in Brazil. Binary logistic regression was used to identify the factors influencing the likelihood of a firm as an attractive alliance partner. Our results indicate that R&D-specific factors influence the likelihood of firms to be attractive alliance partners. In particular, firms showing an in-house innovation history focused on one or few products are more likely to be attractive alliance partners with LEE firms than those that do not. Another R&D-specific predictor that enhances the chances of alliance partner attractiveness with LEE firms is the firm's focused searching and identifying capability relative to technology or equipment that demonstrates good prospects to improve the firm's line of products. A third predictor refers to the firm's awareness regarding non-cost obstacles for its own technological development. Implications for policy makers and practitioners are also discussed.

The effect of H+ on the N-methyl-d-aspartate-induced (NMDA) membrane current in enzymatically isolated catfish cone horizontal cells was investigated. Extracellular acidification to pH 5.5 blocked nearly completely the NMDA-induced current and reduced desensitization. The pK for the H+ effect was 6.5, near that for the free amino acid histidine. Protons did not alter the receptor affinity for NMDA and the inhibition was insensitive to the membrane potential and surface charge screening. However, extracellular H+ increased the IC50 for Zn2+. These results indicate that protons can modulate the NMDA-induced membrane current by a mechanism that may include interaction with histidine residues.

Inositol 1,4,5-trisphosphate (InsP3) mobilizes intracellular stored Ca2+ by binding to specific receptors that are similar to the ryanodine receptor of skeletal and cardiac muscle. We have immunolocalized the InsP3 receptor to the inner nuclear layer and limiting membranes of the catfish retina. Immunocytochemistry on dissociated retinal cells further localized the receptor in the horizontal, bipolar and Müller glial cells. Immunostaining of the rat retina localized the InsP3 receptor to the plexiform layers. These data show a different distribution of InsP3 receptor in the catfish retina compared to that of other vertebrates, that may be suggestive of a different functional role for this receptor in different species.

Participatory Forest Management (PFM) in Tanzania aims to improve forest condition, livelihoods for local people and natural resources governance at the village level. Using data collected from 12 villages and forest areas with (n=10) and without (n=2) participatory forest management across eastern Tanzania we aim to assess how livelihoods of villagers compare between forest management regimes. Data show that most villagers across the study sites are poor, with small numbers of wealthier people. There is little overall income variation across forests under PFM, but there is considerable variation of benefits from the PFM forest between village wealth classes. Richer village members are able to secure preferential access to the PFM forest and utilise it (or benefit from issuing licences) for livestock keeping (in drier forests), charcoal production (close to access routes to towns), and harvesting (where high value timber remains). Data suggest that the PFM approach has made certain sectors of the community more wealthy, typically those setting the rules and enforcing them. But they also indicate that the overall impacts across the community are marginal – and may be negative for the poorest community members.

Rapid Rural Appraisal techniques are frequently used for wealth-ranking of households in rural communities. The main justifications of such approaches are that they are fast, allow prestratification of households in preparation for surveys and that they have been shown to have at least some empirical validity as means of stratifying households by socio-economic status. Sometimes, however, the participatory process may fail to produce consistent wealth categories, or people refuse to accept labels such as ‘poor’ and ‘rich’ and/or are reluctant to assign such categories to households within their village. A household survey in Tanzania was conducted in 12 villages across eastern Tanzania in 2008-2010. In all villages a participatory wealth ranking exercise was conducted and used for stratification of households. Sample households (n=40 per village) were allocated proportionally to wealth categories. The structured household survey emphasized assets, income, and perceived effects of Participatory Forest Management. The value of individual non-productive assets was estimated through a follow-up survey and combined with results from the household survey to estimate total value of assets for each household. In this study the original, partly inconsistent wealth ranking is examined and compared with estimated incomes and asset values. Next, alternative wealth classification rules are introduced and resulting classification outcomes are examined and discussed.

International climate negotiations have stressed the importance of considering emissions from forest degradation under the planned REDD+ (Reducing Emissions from Deforestation and forest Degradation + enhancing forest carbon stocks) mechanism. However, most research, pilot-REDD+ projects and carbon certification agencies have focused on deforestation and there appears to be a gap in knowledge on complex mosaic landscapes containing degraded forests, smallholder agriculture, agroforestry and plantations. In this paper we therefore review current research on how avoided forest degradation may affect emissions of greenhouse gases (GHG) and expected co-benefits in terms of biodiversity and livelihoods. There are still high uncertainties in measuring and monitoring emissions of carbon and other GHG from mosaic landscapes with forest degradation since most research has focused on binary analyses of forest vs. deforested land. Studies on the impacts of forest degradation on biodiversity contain mixed results and there is little empirical evidence on the influence of REDD+ on local livelihoods and tenure security, partly due to the lack of actual payment schemes. Governance structures are also more complex in landscapes with degraded forests as there are often multiple owners and types of rights to land and trees. Recent technological advances in remote sensing have improved estimation of carbon stock changes but establishment of historic reference levels is still challenged by the availability of sensor systems and ground measurements during the reference period. The inclusion of forest degradation in REDD+ calls for a range of new research efforts to enhance our knowledge of how to assess the impacts of avoided forest degradation. A first step will be to ensure that complex mosaic landscapes can be recognised under REDD+ on their own merits.

Understanding the spatial distribution of the quantity and value of Non-Timber Forest Product (NTFP) collection gives insight into the benefits that local communities obtain from forests, and can inform decisions about the selection of forested areas that are eligible for conservation and enforcement of regulations. In this paper we estimate transferable household production functions of NTFP extraction in the Eastern Arc Mountains (EAM) in Tanzania, based on information from several multisite datasets related to the behaviour of over 2000 households. These micro-level models can be used to predict the value of NTFP collection across a broader spatial scale. The study shows that the total benefit flow of charcoal, firewood, poles and thatch from the EAM to the local population has an estimated value of TSH 59 billion (USD 42 million) per year, and provides an important source of additional income for local communities, especially the poorest. We therefore argue that further restrictions on forest access to promote conservation will require additional policies to prevent a consequent increase in poverty, and an enforced trade-off between conservation and energy supply to rural and urban households.

Understanding the spatial distribution of the quantity and value of Non-Timber Forest Product (NTFP) collection gives insight into the benefits that local communities obtain from forests, and can inform decisions about the selection of forested areas that are eligible for conservation and enforcement of regulations. In this paper we estimate transferable household production functions of NTFP extraction in the Eastern Arc Mountains (EAM) in Tanzania, based on information from several multisite datasets related to the behaviour of over 2000 households. These micro-level models can be used to predict the value of NTFP collection across a broader spatial scale. The study shows that the total benefit flow of charcoal, firewood, poles and thatch from the EAM to the local population has an estimated value of TSH 59 billion (USD 42 million) per year, and provides an important source of additional income for local communities, especially the poorest. We therefore argue that further restrictions on forest access to promote conservation will require additional policies to prevent a consequent increase in poverty, and an enforced trade-off between conservation and energy supply to rural and urban households.

It has been suggested that learning an object's location relative to (1) intramaze landmarks and (2) local boundaries is supported by parallel striatal and hippocampal systems, both of which rely upon input from a third system for orientation. However, little is known about the developmental trajectories of these systems' contributions to spatial learning. The present study tested 5- and 7-year-old children and adults on a water maze-like task in which all three types of cue were available. Participants had to remember the location of an object hidden in a circular bounded environment containing a moveable intramaze landmark and surrounded by distal cues. Children performed less accurately than adults, and showed a different pattern of error. While adults relied most on the stable cue provided by the boundary, children relied on both landmark and boundary cues similarly, suggesting a developmental increase in the weighting given to boundary cues. Further, adults were most accurate in coding angular information (dependent on distal cues), whereas children were most accurate in coding distance, suggesting a developing ability to use distal cues to orient. These results indicate that children as young as 5 years use boundary, intramaze landmark, and distal visual cues in parallel, but that the basic accuracy and relative weighting of these cues changes during subsequent development.

Rattlesnakes, copperheads, and other pit vipers have highly sensitive heat detectors known as pit organs, which are used to sense and strike at prey. However, it is not currently known how temperature change triggers cellular and molecular events that activate neurons supplying the pit organ. We dissociated and cultured neurons from the trigeminal ganglia (TG) innervating the pit organs of the Western Diamondback rattlesnake ( Crotalus atrox) and the copperhead ( Agkistrodon contortix) to investigate electrophysiological responses to thermal stimuli. Whole cell voltage-clamp recordings indicated that 75% of the TG neurons from C. atrox and 74% of the TG neurons from A. contortix showed a unique temperature-activated inward current ( IΔT). We also found an IΔT-like current in 15% of TG neurons from the common garter snake, a species that does not have a specialized heat-sensing organ. A steep rise in the current-temperature relationship of IΔTstarted just below 18°C, and cooling temperature-responsive TG neurons from 20°C resulted in an outward current, suggesting that IΔTis on at relatively low temperatures. Ion substitution and Ca2+imaging experiments indicated that IΔTis primarily a monovalent cation current. IΔTwas not sensitive to capsaicin or amiloride, suggesting that the current did not show similar pharmacology to other mammalian heat-sensitive membrane proteins. Our findings indicate that a novel temperature-sensitive conductance with unique ion permeability and low-temperature threshold is expressed in TG neurons and may be involved in highly sensitive heat detection in snakes.