Relevant bibliographies by topics / Spatial pathways

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Spatial pathways'

Author: Grafiati
Published: 6 September 2023

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Journal articles on the topic "Spatial pathways"

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Zandvoort, Mark, Nora Kooijmans, Paul Kirshen, and Adri van den Brink. "Designing with Pathways: A Spatial Design Approach for Adaptive and Sustainable Landscapes." Sustainability 11, no. 3 (January 22, 2019): 565. http://dx.doi.org/10.3390/su11030565.

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Despite rising attention to pathways thinking in multiple domains such as climate adaptation, energy supply planning, and flood risk management, their spatial translation is so far understudied. We set out to study how spatial design based on pathways thinking can help develop more adaptive and sustainable landscapes. Using landscape analysis, field research, and research-through-designing in a case study on climate resilience in Boston (USA), we argue for better understanding of the spatial and design consequences of pathways in general. Our results indicate that pathways can be spatially translated, demanding landscape-informed choices when sequencing different policy actions. We found that spatial designing makes the landscape consequences of pathways transparent and enables policy-makers to replace the input of policy actions with spatial interventions, select pathways according to different underlying design strategies, use the mapped pathways to initiate an iterative research-through-designing process to test and inform different designs, and spatially visualize the pathways and possible sequences of actions. We conclude that policy-makers should be cognizant about the spatial implications of pathways and offer directions to enrich applications of pathways thinking for achieving adaptive and sustainable landscapes.
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Krishnan, J., Lingjun Lu, and Aiman Alam Nazki. "The interplay of spatial organization and biochemistry in building blocks of cellular signalling pathways." Journal of The Royal Society Interface 17, no. 166 (May 2020): 20200251. http://dx.doi.org/10.1098/rsif.2020.0251.

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Biochemical pathways and networks are central to cellular information processing. While a broad range of studies have dissected multiple aspects of information processing in biochemical pathways, the effect of spatial organization remains much less understood. It is clear that space is central to intracellular organization, plays important roles in cellular information processing and has been exploited in evolution; additionally, it is being increasingly exploited in synthetic biology through the development of artificial compartments, in a variety of ways. In this paper, we dissect different aspects of the interplay between spatial organization and biochemical pathways, by focusing on basic building blocks of these pathways: covalent modification cycles and two-component systems, with enzymes which may be monofunctional or bifunctional. Our analysis of spatial organization is performed by examining a range of ‘spatial designs’: patterns of localization or non-localization of enzymes/substrates, theoretically and computationally. Using these well-characterized in silico systems, we analyse the following. (i) The effect of different types of spatial organization on the overall kinetics of modification, and the role of distinct modification mechanisms therein. (ii) How different information processing characteristics seen experimentally and studied from the viewpoint of kinetics are perturbed, or generated. (iii) How the activity of enzymes (bifunctional enzymes in particular) may be spatially manipulated, and the relationship between localization and activity. (iv) How transitions in spatial organization (encountered either through evolution or through the lifetime of cells, as seen in multiple model organisms) impacts the kinetic module (and pathway) behaviour, and how transitions in chemistry may be impacted by prior spatial organization. The basic insights which emerge are central to understanding the role of spatial organization in biochemical pathways in both bacteria and eukaryotes, and are of direct relevance to engineering spatial organization of pathways in bottom-up synthetic biology in cellular and cell-free systems.
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Von Gerhardt, K., A. Van Niekerk, M. Kidd, M. Samways, and J. Hanks. "The role of elephantLoxodonta africanapathways as a spatial variable in crop-raiding location." Oryx 48, no. 3 (February 13, 2014): 436–44. http://dx.doi.org/10.1017/s003060531200138x.

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AbstractShort-range elephantLoxodonta africanamovements were examined in a heterogeneous landscape mosaic of settlements, crop fields and remnant forest in the Caprivi Strip, Namibia. We explored the penetration of the landscape through the use of permanent pathways and determined the impact of pathway use on crop-raiding location. Pathways were linear, devoid of vegetation and maintained by repeated movement. Functional connectivity of pathways was not species-specific, and pathways were used by various species. Elephants travelled in single file at night and we recorded selective pathway use: females selected pathways away from settlements to access water, whereas males used pathways among settlements to launch crop raids. Proximity of raided fields to the nearest pathway was the only significant spatial variable explaining crop-raiding location. Bulls were responsible for all crop-raiding incidents. We conclude that (1) pathways were the most significant spatial variable influencing which fields were raided, (2) crop-raiding from pathways may maximize foraging efficiency by reducing time spent and distance travelled while foraging, (3) pathways may facilitate penetration of the matrix by connecting predictable resources (crops) with preferred shelter areas, crossing points at roads and preferred drinking spots, and (4) access to the Kwandu River is restricted by settlements, predictably resulting in human–elephant conflict. By highlighting the relevance of pathways for movement of elephants we show that an understanding of the use of pathways is important for land-use planning in conservation landscapes, specifically with regard to human–elephant conflict. We also argue for the need to more fully explore pathway occurrence and use at larger spatial scales.
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Beaudot, W. H. A. "Dynamics in Parvocellular and Magnocellular Pathways: Consequences for Luminance and Colour Processing Streams." Perception 25, no. 1_suppl (August 1996): 9. http://dx.doi.org/10.1068/v96l0710.

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An achromatic neuromorphic model of the vertebrate retina has already accounted for X and Y pathways (Beaudot and Hérault, 1994 Perception23 Supplement, 25) and has shown a temporal ‘coarse-to-fine’ processing of spatial information (Beaudot et al, 1995 Perception24 Supplement, 93). This model has been extended to colour vision. By taking into account the chromatic sensitivities of cones, functional properties of the parvocellular pathway are modelled. Approximating the responses of colour-opponent cells, the model provides a spatial multiplexing of luminance and chrominance information: sustained responses show spatial band-pass behaviour to luminance variations and low-pass behaviour to equiluminant colour changes. In addition the spatiotemporal inseparability for luminance in the parvocellular model leads to a temporal multiplexing of spatial luminance information: at higher temporal frequencies the spatial filtering is low-pass, conveying only luminance information. Demultiplexing this mixed information suggests interactions between retinal channels. By locally combining additive and subtractive mechanisms between opposite parvocellular pathways (eg G+/ R−± R+/ G−), and an inhibition from the magnocellular pathway, the existence of at least three functional subchannels is predicted: (i) a transient, spatially low-pass channel, (ii) a sustained, spatially band-pass channel, dedicated to the analysis of luminance information in a spatiotemporally separable way (eg moving shadows and static textures), and (iii) a spatiotemporally low-pass, colour-opponent channel leading to colour induction, which is little affected by the presence of shadows and is more representative of objects. This hypothesis of spatiotemporal demultiplexing of luminance and chrominance information, which should presumably occur at an early cortical level, is in accordance with the multiple-processing-streams organisation of the primate visual system.
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Findlay, John M., and Robin Walker. "A model of saccade generation based on parallel processing and competitive inhibition." Behavioral and Brain Sciences 22, no. 4 (August 1999): 661–74. http://dx.doi.org/10.1017/s0140525x99002150.

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During active vision, the eyes continually scan the visual environment using saccadic scanning movements. This target article presents an information processing model for the control of these movements, with some close parallels to established physiological processes in the oculomotor system. Two separate pathways are concerned with the spatial and the temporal programming of the movement. In the temporal pathway there is spatially distributed coding and the saccade target is selected from a “salience map.” Both pathways descend through a hierarchy of levels, the lower ones operating automatically. Visual onsets have automatic access to the eye control system via the lower levels. Various centres in each pathway are interconnected via reciprocal inhibition. The model accounts for a number of well-established phenomena in target-elicited saccades: the gap effect, express saccades, the remote distractor effect, and the global effect. High-level control of the pathways in tasks such as visual search and reading is discussed; it operates through spatial selection and search selection, which generally combine in an automated way. The model is examined in relation to data from patients with unilateral neglect.
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MADRID, M., and M. A. CROGNALE. "Long-term maturation of visual pathways." Visual Neuroscience 17, no. 6 (November 2000): 831–37. http://dx.doi.org/10.1017/s0952523800176023.

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Previous research in adults has demonstrated the utility of the visual evoked potential (VEP) to measure the integrity of the chromatic and achromatic visual pathways. The VEP has also been shown to be a valuable indicator of maturation of these pathways in infants up to 1 year of age. The present manuscript reports changes in the visual pathways from 2 years to adulthood as measured by the spatio-chromatic VEP. The responses to achromatic reversal stimuli designed to preferentially activate the low spatial-frequency achromatic (luminance) pathways appear adult-like by 1 year of age. The responses to low spatial-frequency isoluminant onset stimuli designed to preferentially activate the chromatic pathway do not appear as they do in the adult until after 12–13 years of age. The shapes of the chromatic VEP waveforms shift from a positive–negative complex to a negative–positive complex. These changes can be modeled by a decrease in the latency of a large negative component between the ages of 1 year and adulthood. The results suggest that for low spatial-frequency stimuli, there are long-term changes in the development of the chromatic pathways that are not observed in the low spatial-frequency achromatic pathways. The changes in the chromatic VEP waveforms with age may be a physiological correlate of reported behavioral changes.
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Atay, Oguzhan, and Jan M. Skotheim. "Spatial and temporal signal processing and decision making by MAPK pathways." Journal of Cell Biology 216, no. 2 (January 2, 2017): 317–30. http://dx.doi.org/10.1083/jcb.201609124.

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Mitogen-activated protein kinase (MAPK) pathways are conserved from yeast to man and regulate a variety of cellular processes, including proliferation and differentiation. Recent developments show how MAPK pathways perform exquisite spatial and temporal signal processing and underscores the importance of studying the dynamics of signaling pathways to understand their physiological response. The importance of dynamic mechanisms that process input signals into graded downstream responses has been demonstrated in the pheromone-induced and osmotic stress–induced MAPK pathways in yeast and in the mammalian extracellular signal-regulated kinase MAPK pathway. Particularly, recent studies in the yeast pheromone response have shown how positive feedback generates switches, negative feedback enables gradient detection, and coherent feedforward regulation underlies cellular memory. More generally, a new wave of quantitative single-cell studies has begun to elucidate how signaling dynamics determine cell physiology and represents a paradigm shift from descriptive to predictive biology.
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Nilsson, Thomy. "Spatial Multiplexing." International Journal of Adaptive, Resilient and Autonomic Systems 5, no. 4 (October 2014): 46–70. http://dx.doi.org/10.4018/ijaras.2014100104.

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Geometrical constraints limit how much information can be received and emitted along real pathways across the boundary of any processor. Applied to central nervous systems this imposes a seemingly impassable bottleneck to the evolution of large brains. A small brain could never access enough information to warrant a larger brain. A small brain could not send enough information to operate a large body. Larger bodies are needed to support larger brains. Thus, with a rare exception, there are no invertebrates with large brains or large bodies. It is proposed that a convergent-divergent scanning neural network developed which enabled vertebrates to squeeze more information through this bottleneck by “spatial multiplexing”. This reduces the number of pathways into, between and from processors by a factor of 16 while maintaining spatial and intensity accuracy. This paper describes spatial multiplexing using downloadable spreadsheet models and shows how the necessity of scanning likely introduced brain rhythms.
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Han, Zhixian, and Anne Sereno. "Modeling the Ventral and Dorsal Cortical Visual Pathways Using Artificial Neural Networks." Neural Computation 34, no. 1 (January 1, 2022): 138–71. http://dx.doi.org/10.1162/neco_a_01456.

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Abstract Although in conventional models of cortical processing, object recognition and spatial properties are processed separately in ventral and dorsal cortical visual pathways respectively, some recent studies have shown that representations associated with both objects' identity (of shape) and space are present in both visual pathways. However, it is still unclear whether the presence of identity and spatial properties in both pathways have functional roles. In our study, we have tried to answer this question through computational modeling. Our simulation results show that both a model ventral and dorsal pathway, separately trained to do object and spatial recognition, respectively, each actively retained information about both identity and space. In addition, we show that these networks retained different amounts and kinds of identity and spatial information. As a result, our modeling suggests that two separate cortical visual pathways for identity and space (1) actively retain information about both identity and space (2) retain information about identity and space differently and (3) that this differently retained information about identity and space in the two pathways may be necessary to accurately and optimally recognize and localize objects. Further, modeling results suggests these findings are robust and do not strongly depend on the specific structures of the neural networks.
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Housden, Benjamin E., and Norbert Perrimon. "Spatial and temporal organization of signaling pathways." Trends in Biochemical Sciences 39, no. 10 (October 2014): 457–64. http://dx.doi.org/10.1016/j.tibs.2014.07.008.

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Dissertations / Theses on the topic "Spatial pathways"

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Shires, Katherine L. "Using IEG's to uncover pathways for spatial learning in the rat." Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/54312/.

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This thesis concentrates on the induction of the immediate early genes zif268 and c-fos in a functional and dysfunctional brain network. Initial studies focused on the creation of a task to allow the study of immediate early gene activation after working memory. Previous studies using such a paradigm have compared the animals performing the experimental task with poorly matched control groups. Experiments in this thesis attempted to rectify this. A group of experiments using the water maze found decreases in Zif268 activation in the experimental group as compared to control groups, mainly in the hippocampus and some parahippocampal areas. This was believed to have arisen because of a streamlining of the brain network in the Working Memory group. An increase in c-Fos immunoreactivity was seen in the Working Memory group as compared to controls in prefrontal regions. Structural equation modelling analysis was performed, which allows immediate early gene counts to be used to analyse networks of brain regions. In the Working Memory group connections were seen between the parahippocampal regions and the subiculum that progressed via the hippocampus, indicating that the hippocampus was still engaged by the task. In the control group analysed no such hippocampal pathway was found. This water maze task was then used to study zif268-EGFP activation in a novel transgenic rodent model, where the Zif268 promoter drives the expression of a fluorescent protein EGFP. Activation of both EGFP and Zif268 immunoreactivity was seen in the CA1 region of the animals performing the control task. No EGFP activation was seen in this region in the Working Memory group even though EGFP expression was seen in other regions. The GFP protein was also able to be seen under direct visualisation in the CA1 and dentate gyrus region of control animals. Concerning the dysfunctional brain, gene expression was analysed in the retrosplenial cortex after NMDA lesions of the anterior thalamic nuclei. Previous research has shown that lesions produce a dramatic hypoactivity in the protein products of the immediate early genes c-fos and zif268. Microarray analysis of retrosplenial tissue revealed that as well as decreases in expression of genes related to repair and cell adhesion/neurogenesis, an increase in c-fos mRNA was seen in the lesion hemisphere of the brain. This pattern of expression is opposite to that of the protein. Possible reasons for this are discussed.
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Shimizu, Thomas Simon. "The spatial organisation of cell signalling pathways - a computer-based study." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620667.

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Das, Keshav. "Effect of aeration pathways on spatial homogeneity during in- vessel composting /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487929745333841.

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Xie, Yu. "Spatial Distribution and Pathways of Arsenic in Shepley's Hill Landfill, Ayer, Massachusetts." Thesis, Boston College, 2013. http://hdl.handle.net/2345/3241.

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Thesis advisor: Rudolph Hon
Groundwater in the Shepley's Hill Landfill (SHL) area had a high arsenic concentration for at least 20 years. This study is aimed at understanding the migration pathways of arsenic in the SHL area and postulating the possible sources and mechanisms for the mobilization of arsenic. A direct-push sampling technique (DPT) was applied in the summer of 2010 within the SHL and its downgradient area, which provided groundwater samples from various depths and locations. A long-term monitoring dataset from 1998 to 2009 was utilized as a subsidiary source for temporal analysis. Spatial distributions of arsenic and other major dissolved compositions were analyzed. Extremely high arsenic concentrations (up to ~ 15000 µg/L) were detected in the deep glacial sand deposits close to a peat layer within the SHL. Arsenic concentrations decrease dramatically in the downgradient area north of the SHL. The transport of arsenic in the SHL area is similar to that of iron. The source of arsenic is likely to been within the boundary of the SHL. The glacial sand overburden within the SHL provides enough source for the arsenic mobilization. A possible mechanism of arsenic mobilization in the SHL area is that the reductive dissolution/desorption of arsenic from iron bearing minerals under a lasting reducing environment created by decompositions of organic matter in waste and peat
Thesis (MS) — Boston College, 2013
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Earth and Environmental Sciences
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Charles, David P. "The role of the hippocampal input/output pathways in objetc, spatial and temporal memory." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409711.

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Smirnov, Anna. "Polycyclic aromatic hydrocarbons in sediments of Lake Erie, Great Lakes : spatial distribution, sources and pathways /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq23174.pdf.

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Seeliger, Christine. "Spatial and stochastic modeling of TrkB mediated signaling pathways involved in long term potentation in the dendritic spine." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708013.

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Harvey, Catherine. "How spatial planning can enable pathways to the implementation of sustainable urban drainage systems in the city bowl, Cape Town." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/28179.

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The dramatic global trend of population growth has led to a rapid urbanisation, resulting in unprecedented land cover change. The incarnation of accompanying developed has typified impermeable surfaces. These surfaces have disconnected the stormwater component of the natural hydrological cycle, disregarding it as a nuisance and designing it to be rapidly removed from urban areas. Utilising Sustainable Urban Drainage Systems (SUDS) offers opportunities in urban areas to recycle the water and challenge the perception that stormwater is a nuisance and of no value. The current context of drought experienced by Cape Town has highlighted the need for less reliance on surface water resources; implementing SUDS could be a way of reconnecting the hydrological urban water cycle. It could also help to repair the human disconnect from nature that is prevalent in urban areas. The research question explored the role of spatial planning in enabling the implementation of SUDS in the City Bowl, Cape Town. While conceptual and technical frameworks have been developed for SUDS in South Africa, at present there is no spatial guide as to how these interventions could be realised in a specific context and area. This research utilise s the tools of spatial planning to re-imagine the City Bowl in relation to water. The case study methods used, enabling a detailed understanding of the site. This was complemented by interviews with various planning professionals in order to understand the current role spatial planning plays in terms of implementing SUDS. The research suggest is that whilst SUDS has many constraints, the opportunities that they provide for improving water quality and quantity, and surrounding amenities, suggests that this is one which has to be embraced if the City Bowl is going to respond innovatively and sustainably to the drought. It also highlights the need to improve coordination across different spheres and departments of governance, and emphasises the need to value local community knowledge. A prevalent silo approach to complex problems is no longer acceptable. The implications of the research are that implementing SUDS in the City Bowl requires planners to embrace a water literacy approach to spatial plans, and in doing so, return the focus to water
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Anzelc, Avis M. "The Foraging and Travel Patterns of White-Faced Sakis in Brownsberg Nature Park, Suriname: Preliminary Evidence for Goal-Directed Foraging Behavior." [Kent, Ohio] : Kent State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1248111886.

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Thesis (M.A.)--Kent State University, 2009.
Title from PDF t.p. (viewed Mar. 16, 2010). Advisor: Marilyn Norconk. Keywords: White-faced sakis; goal-directed foraging; spatial memory; mental maps; arboreal pathways; distance-minimization; topographical mental mapping; preference. Includes bibliographical references (p. 183-194).
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Sach, Andrew John. "Auditory spatial attention." Thesis, University of York, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325696.

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Books on the topic "Spatial pathways"

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Jędrysek, Mariusz Orion. Spatial and temporal variations in carbon isotope ratio of early-diagenetic methane from freshwater sediments: Methanogenic pathways. Wrocław: Wydawn. Uniwersytetu Wrocławskiego, 1997.

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Takao, Kumazawa, Kruger Lawrence, and Mizumura Kazue, eds. The polymodal receptor: A gateway to pathological pain. Amsterdam: Elsevier, 1996.

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Signal Processing in Auditory Neuroscience: Temporal and Spatial Features of Sound and Speech. Elsevier Science & Technology, 2018.

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Ando, Yoichi. Signal Processing in Auditory Neuroscience: Temporal and Spatial Features of Sound and Speech. Elsevier Science & Technology Books, 2018.

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Graif, Corina. Mobility in Isolation: Neighborhood Effects, Spatial Embeddedness, and Inequality in the Migration Pathways of the Urban Poor. 2011.

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Koinova, Maria. Diaspora Entrepreneurs and Contested States. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198848622.001.0001.

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Why do conflict-generated diasporas mobilize in contentious and non-contentious ways or use mixed strategies of contention? Why do they channel their homeland-oriented goals through host-states, transnational networks, and international organizations? This book develops a theory of socio-spatial positionality and its implications for the individual agency of diaspora entrepreneurs, moving beyond essentialized notions of diasporas as groups. Individual diaspora entrepreneurs operate in transnational social fields affecting their mobilizations beyond dynamics confined to host-states and original home-states. There are four types of diaspora entrepreneurs—Broker, Local, Distant, and Reserved—depending on the relative strength of their socio-spatial linkages to host-land, on the one hand, and original homeland and other global locations, on the other. A two-level typological theory captures nine causal pathways, unravelling how the socio-spatial linkages of these diaspora entrepreneurs interact with external factors: host-land foreign policies, homeland governments, parties, non-state actors, and critical events or limited global influences. Such pathways produce mobilization trajectories with varying levels of contention and methods of channelling homeland-oriented goals. Non-contentious pathways often occur when host-state foreign policies are convergent with the diaspora entrepreneurs’ goals, and when diaspora entrepreneurs can act autonomously. Dual-pronged contention pathways occur quite often, under the influence of homeland governments, non-state actors, and political parties. The most contentious pathway occurs in response to violent critical events in the homeland or adjacent to it fragile states. This book is informed by 300 interviews and a dataset of 146 interviews with diaspora entrepreneurs among the Albanian, Armenian, and Palestinian diasporas in the UK, Germany, France, Netherlands, Sweden, and Switzerland, as well as Kosovo and Armenia in the European neighbourhood.
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Madi, Matteo, and Olga Sokolova. Space Debris Peril: Pathways to Opportunities. Taylor & Francis Group, 2022.

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Madi, Matteo, and Olga Sokolova. Space Debris Peril: Pathways to Opportunities. Taylor & Francis Group, 2020.

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Madi, Matteo, and Olga Sokolova. Space Debris Peril: Pathways to Opportunities. Taylor & Francis Group, 2020.

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Madi, Matteo, and Olga Sokolova. Space Debris Peril: Pathways to Opportunities. Taylor & Francis Group, 2020.

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Book chapters on the topic "Spatial pathways"

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Cairns, David, and Marine Sargsyan. "Spatial Pathways to Work." In Student and Graduate Mobility in Armenia, 31–45. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-19613-4_3.

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Kerkhoff, Georg, Gilles Rode, and Stephanie Clarke. "Treating Neurovisual Deficits and Spatial Neglect." In Clinical Pathways in Stroke Rehabilitation, 191–217. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-58505-1_11.

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Ingwani, Emaculate, Madilonga Trevor Mukwevho, Trynos Gumbo, and Masala Thomas Makumule. "Transformation Pathways to Smart Villages." In Sustainable and Smart Spatial Planning in Africa, 41–53. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003221791-6.

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Seo, S. Niggol. "Von Thunen’s Spatial Land Use: Grasslands and Cities." In The Economics of Optimal Growth Pathways, 59–82. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-20754-9_3.

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Marchese, Emilia Poli, Lidia Di Benedetto, and Giuseppe Maugeri. "Successional pathways of Mediterranean evergreen vegetation on Sicily." In Temporal and Spatial Patterns of Vegetation Dynamics, 185–91. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-2275-4_20.

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Sharma, Samir. "Control of mitochondrial metabolism through functional and spatial integration of mitochondria." In Alternative respiratory pathways in higher plants, 115–55. Chichester, UK: John Wiley & Sons, Ltd, 2015. http://dx.doi.org/10.1002/9781118789971.ch7.

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Smith, F. Donelson, Lorene K. Langeberg, and John D. Scott. "Spatial and Temporal Control of Cell Signaling by A-Kinase Anchoring Proteins." In Signal Transduction: Pathways, Mechanisms and Diseases, 183–97. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-02112-1_10.

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Ungerleider, Leslie G. "The Corticocortical Pathways for Object Recognition and Spatial Perception." In Experimental Brain Research Supplementum, 21–37. Berlin, Heidelberg: Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-662-09224-8_2.

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Ke, Zhang. "The impact pathways of economic agglomeration on environmental pollution and environmental efficiency." In The Emission Reduction Effects of Spatial Agglomeration, 82–106. London: Routledge, 2022. http://dx.doi.org/10.4324/9781003322016-4.

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Acheampong, Ransford A. "Epilogue: Perspectives on Pathways Towards a Responsive Spatial Planning System." In The Urban Book Series, 289–302. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-02011-8_13.

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Conference papers on the topic "Spatial pathways"

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Buck, Steven L., and Roger Knight. "Model of dual rod pathways." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1989. http://dx.doi.org/10.1364/oam.1989.fk2.

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We offer a model of dual rod pathways that incorporate recent psychophysical, physiological, and anatomical work. Flicker sensitivity studies suggest that one rod pathway, π0, has greater absolute sensitivity but poorer high temporal frequency responses than the other pathway, π0 (Conner, 1982; Connor and MacLeod, 1977; Sharpe, Stockman, and MacLeod, in press). The dual pathways may arise from differential electrical coupling of rods and cones via gap junctions as a function of adaptation level (Yang and Wu, 1989), so that π0 signals travel through rod pathways and π0 signals travel through cone pathways (Smith, Freed, and Sterling, 1986) before being recombined at ganglion cells or beyond. So far, the importance of dual rod pathways for processing other than temporal information is unclear. Our model of dual rod pathways generalizes their role to incremental and spatial processing and makes testable predictions to challenge the model. Predictions include more conelike spatial sensitivity for π0, differential dependence of π0 and π0 increment sensitivity on spatial and temporal parameters, and different interactions of cone signals with π0 and π0 in detection and adaptation. Support for the model comes in part from kinks in increment t.v.i. curves observed in various labs at –2 to 0 log scot td (the same as for flicker data).
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Olzak, Lynn A., and James P. Thomas. "Information integration across spatially tuned pathways." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/oam.1990.me5.

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In a complex spatial-frequency discrimination task, the observer distinguishes between two stimuli, each of which contains two grating patches superimposed at orthogonal orientations. When the frequencies of both components increase (or both decrease) the combined change is more discriminable than when one increases and the other decreases. The result challenges vector models because the magnitude of the difference vector at each orientation is the same in both cases, yet performance is different. The result cannot easily be explained on the basis of overlapping bandwidths, pathway interactions, or noise or on the grounds that the viewer uses one component as a standard against which the other component is compared. Thus, the configurational effect probably does not reflect properties of the V1 representation by spatially tuned pathways; rather, it reflects properties of a later stage of processing.
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Wilson, Hugh R. "Interaction of first- and second-order processes in 2D motion perception." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/oam.1992.mnn1.

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Recent psychophysical experiments have shown that the perceived direction of motion of plaids, composed of two cosine gratings moving in different directions, can deviate by up to 50° from the true direction of rigid translation. We have developed a dynamic neural network model that predicts these and other motion data. The model incorporates two motion pathways that are subsequently combined by using a vector sum operation. The first motion pathway extracts the directions of motion of the component gratings, i.e., the Fourier motion signals, while the second pathway employs filtering and full-wave rectification to extract a non-Fourier motion signal. The vector sum of these motion pathways quantitatively predicts the psychophysical data, and it explains the existence of parallel input pathways from both V1 and V2 to area MT. The model correctly predicts that non-Fourier plaids will move in the vector sum direction, and interactions across spatial scales in the model accurately predict transitions from rigid to transparent motion.
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Sharpe, Lindsay T., Clemens Fach, Jörg Hofmeister, and Andrew Stockman. "Effect of target size on the fast and slow rod pathways." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/oam.1991.mkk5.

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Psychophysical and electroretinographic observations in normal observers and achromats (who lack cone vision) suggest that rod signals have access to two retinal pathways: one, slow and sensitive; the other, fast and insensitive. The two are revealed by double-branched rod-detected flicker threshold vs intensity (ftvi) curves, and by a suprathreshold intensity region (below cone detection)—the perceptual null—within which the sensation of 15-Hz flicker is canceled. The cause of the null is believed to be destructive interference between signals conveyed by the two pathways. Here we report that the break in the 15-Hz ftvi curve and the perceptual null is not found, in either the normal or achromat observer when the flickering target is ≤2° in diameter. Phase measurements (relative to a cone standard) indicate that the faster rod pathway mediates flicker detection for targets of ≤2°, not because the signals from the slow pathway are severely diminished but because destructive interference between the slow and fast rod flicker signals keeps the slow signals from ever exceeding threshold. There is therefore no need to invoke differences in spatial integration between the two pathways to explain the large difference in the ftvi curves.
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Luo, Ming, and Chongcheng Chen. "Potential sources and transport pathways of PM2.5 in Shanghai, China." In 2015 2nd IEEE International Conference on Spatial Data Mining and Geographical Knowledge Services (ICSDM). IEEE, 2015. http://dx.doi.org/10.1109/icsdm.2015.7298034.

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Cao, Dewen, Yaoxiong Wang, Shouzhi Li, Ling Yang, Shuang Feng, and Gao Fang. "Distinction of different two-photon transition pathways by spatial coherent control." In 2017 36th Chinese Control Conference (CCC). IEEE, 2017. http://dx.doi.org/10.23919/chicc.2017.8028911.

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Fairchild, Mark D., and Peter Lennie. "Ganglion cell pathways for rod acuity." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1988. http://dx.doi.org/10.1364/oam.1988.tuh1.

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We examined the acuity of the human rod system pyschophysically to establish whether the parvocellar P or magnocellular M pathway carries high-frequency spatial information in scotopic vision. We measured visual acuity for smalt patches of sinusoidal grating at a range of eccentricities in temporal retina. When the targets were detected via rods, visual acuity ranged from 5.3 cycles/deg at an eccentricity of 5-2.9 cycles/deg at an eccentricity of 30°. We also calculated the highest spatial frequency that could be reliably resolved by the mosaics of Pand M cells and found that visual acuity of the rod system is too high to be supported by the M-ganglion cells. The psychophysical acuity is also lower than the Nyquist limit for P-ganglion cells. This implies that the high-frequency information for scotopic vision is carried in the P-cell pathway and that visual acuity is limited by the sizes of the receptive fields of individual cells, not by their separation. This conclusion is corroborated by our failure to find aliasing in scotopic vision, despite our finding clear aliases when corresponding measurements of acuity were made in photopic conditions.
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Ruth, Mark F., Victor Diakov, Melissa J. Laffen, and Thomas A. Timbario. "Projected Cost, Energy Use, and Emissions of Hydrogen Technologies for Fuel Cell Vehicles." In ASME 2010 8th International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2010. http://dx.doi.org/10.1115/fuelcell2010-33185.

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Each combination of technologies necessary to produce, deliver, and distribute hydrogen for transportation use has a corresponding levelized cost, energy requirement, and greenhouse gas emission profile depending upon the technologies’ efficiencies and costs. Understanding the technical status, potential, and tradeoffs is necessary to properly allocate research and development (R&D) funding. In this paper, levelized delivered hydrogen costs, pathway energy use, and well-to-wheels (WTW) energy use and emissions are reported for multiple hydrogen production, delivery, and distribution pathways. Technologies analyzed include both central and distributed reforming of natural gas and electrolysis of water, and central hydrogen production from biomass and coal. Delivery options analyzed include trucks carrying liquid hydrogen and pipelines carrying gaseous hydrogen. Projected costs, energy use, and emissions for current technologies (technology that has been developed to at least the bench-scale, extrapolated to commercial-scale) are reported. Results compare favorably with those for gasoline, diesel, and E85 used in current internal combustion engine (ICE) vehicles, gasoline hybrid electric vehicles (HEVs), and flexible fuel vehicles. Sensitivities of pathway cost, pathway energy use, WTW energy use, and WTW emissions to important primary parameters were examined as an aid in understanding the benefits of various options. Sensitivity studies on production process energy efficiency, total production process capital investment, feed stock cost, production facility operating capacity, electricity grid mix, hydrogen vehicle market penetration, distance from the hydrogen production facility to city gate, and other parameters are reported. The Hydrogen Macro-System Model (MSM) was used for this analysis. The MSM estimates the cost, energy use, and emissions trade offs of various hydrogen production, delivery, and distribution pathways under consideration. The MSM links the H2A Production Model, the Hydrogen Delivery Scenario Analysis Model (HDSAM), and the Greenhouse Gas, Regulated Emission, and Energy for Transportation (GREET) Model. The MSM utilizes the capabilities of each component model and ensures the use of consistent parameters between the models to enable analysis of full hydrogen production, delivery, and distribution pathways. To better understand spatial aspects of hydrogen pathways, the MSM is linked to the Hydrogen Demand and Resource Analysis Tool (HyDRA). The MSM is available to the public and enables users to analyze the pathways and complete sensitivity analyses.
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Hofmann, Martin I., and Peter E. Hallett. "Simple model of the early visual pathways." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/oam.1987.wl8.

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The model consists of discrete units, both spatial and temporal. The outputs are also restricted to discrete values and are nonlinear functions of the input. Units are arranged in three levels: (1) analogous to the photoreceptors, the image is sampled by a hexagonal array of units; (2) analogous to the center-surround-type cells, each unit is excited by nearby receptor units and inhibited by more distant units; (3) analogous to simple cells in the visual cortex, the units receive excitatory input from a band of center-surround units and inhibitory input from adjacent bands to produce a series of six orientation selective units. An important feature at level (3) is connectivity between the orientation selective units. In a local region of space excitatory connections exist between similarly oriented units and inhibitory connections between orthogonally oriented units. Consequently the properties of level (3) units are modified as the system iterates. The effect of this position-orientation interaction is to sharpen the tuning curves for both orientation and spatial frequency selectivity. The outputs of the units in level (3) may also serve as a basis for simple texture discrimination.
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Lennie, Peter. "Central pathways for color vision." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.tuf1.

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Psychophysical evidence suggests that signals from cones are later transformed to yield an achromatic signal and two chromatically opponent ones. Although physiological observations on the lateral geniculate nucleus (LGN) of the macaque monkey have confirmed the existence of opponent transformations, these differ in important respects from the kind inferred from psychophysical evidence. In particular, the red-green chromatic pathway appears also to carry an achromatic signal, to an extent determined by the spatial properties of the stimulus. The characteristics of the yellow-blue pathway also differ from those inferred from psychophysical observations. Although signals that arise in the LGN do not meet the requirements of the psychophysical model, a linear transformation of these signals could do the required job. Analysis of the chromatic properties of neurons in striate cortex (the recipient of information from the LGN) shows that signals from the LGN are transformed substantially, so as to resemble more closely those expected on psychophysical grounds. The second-stage mechanisms inferred from psychophysical observations therefore seem to reflect the action of at least two distinct physiological transformations.
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Reports on the topic "Spatial pathways"

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Rosemarin, Arno, Guoyi Han, Matilda Gunnarsson, Karina Barquet, and Elin Leander. Opportunities for applying spatial management approaches in the Antarctic marine space. Stockholm Environment Institute, June 2023. http://dx.doi.org/10.51414/sei2023.039.

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This paper takes both historical and future-oriented perspectives to explore the Commission on the Conservation of Antarctic Marine Living Resources (CCAMLR) as an integral part of the Antarctic Treaty system (ATS), its accomplishments, current challenges and possible future pathways, with a focus on area-based marine management approaches including marine protected areas (MPAs).
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Klüsener, Sebastian. Spatial variation in non-marital fertility across Europe: recent trends, past path dependencies, and potential future pathways. Rostock: Max Planck Institute for Demographic Research, May 2015. http://dx.doi.org/10.4054/mpidr-wp-2015-001.

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Boudreau, Aaron. Signaling Crosstalk: A Live in Situ Analysis of the Temporal and Spatial Regulation of Key Pathways in Human Breast Cancer Progression. Fort Belvoir, VA: Defense Technical Information Center, May 2007. http://dx.doi.org/10.21236/ada472111.

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LaHatte, W., Ahmad Tavakoly, Sara Lytle, and James Lewis. Mississippi River climate model–based hydrograph projections at the Tarbert Landing location. Engineer Research and Development Center (U.S.), May 2023. http://dx.doi.org/10.21079/11681/47084.

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To better understand and prepare for the possible effects associated with potential climate changes on the lower Mississippi River, the State of Louisiana Coastal Protection and Restoration Authority sought information on the historical, current, and projected future hydrodynamics of the Mississippi River. To this end, flow duration curves (FDC) for the Tarbert Landing location were generated, based on climate models derived from two of the four scenarios of the Coupled Model Intercomparison Project, Phase 5 (CMIP5), multimodel ensemble representative concentration pathways (RCPs). The global CMIP5 datasets were used by the variable infiltration capacity land surface model to produce a runoff dataset, using a bias-correction spatial disaggregation approach. The runoff datasets were then applied to simulate streamflow using the Routing Application for Parallel computatIon of Discharge (RAPID) river routing model. Based on the streamflow, FDCs were calculated for 16 CMIP5 as well as observed historical data at the Tarbert Landing location. Key observations from the results are that the 90th percentile exceedance of the simulated versus the observed flows is more frequent for the RCP 8.5 scenario than for the RCP 4.5 scenario and that the maximum annual flows for the RCP 8.5 scenario are generally smaller than for the RCP 4.5 scenario.
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Or, Dani, Shmulik Friedman, and Jeanette Norton. Physical processes affecting microbial habitats and activity in unsaturated agricultural soils. United States Department of Agriculture, October 2002. http://dx.doi.org/10.32747/2002.7587239.bard.

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experimental methods for quantifying effects of water content and other dynamic environmental factors on bacterial growth in partially-saturated soils. Towards this end we reviewed critically the relevant scientific literature and performed theoretical and experimental studies of bacterial growth and activity in modeled, idealized and real unsaturated soils. The natural wetting-drying cycles common to agricultural soils affect water content and liquid organization resulting in fragmentation of aquatic habitats and limit hydraulic connections. Consequently, substrate diffusion pathways to soil microbial communities become limiting and reduce nutrient fluxes, microbial growth, and mobility. Key elements that govern the extent and manifestation of such ubiquitous interactions include characteristics of diffusion pathways and pore space, the timing, duration, and extent of environmental perturbations, the nature of microbiological adjustments (short-term and longterm), and spatial distribution and properties of EPS clusters (microcolonies). Of these key elements we have chosen to focus on a manageable subset namely on modeling microbial growth and coexistence on simple rough surfaces, and experiments on bacterial growth in variably saturated sand samples and columns. Our extensive review paper providing a definitive “snap-shot” of present scientific understanding of microbial behavior in unsaturated soils revealed a lack of modeling tools that are essential for enhanced predictability of microbial processes in soils. We therefore embarked on two pronged approach of development of simple microbial growth models based on diffusion-reaction principles to incorporate key controls for microbial activity in soils such as diffusion coefficients and temporal variations in soil water content (and related substrate diffusion rates), and development of new methodologies in support of experiments on microbial growth in simple and observable porous media under controlled water status conditions. Experimental efforts led to a series of microbial growth experiments in granular media under variable saturation and ambient conditions, and introduction of atomic force microscopy (AFM) and confocal scanning laser microscopy (CSLM) to study cell size, morphology and multi-cell arrangement at a high resolution from growth experiments in various porous media. The modeling efforts elucidated important links between unsaturated conditions and microbial coexistence which is believed to support the unparallel diversity found in soils. We examined the role of spatial and temporal variation in hydration conditions (such as exist in agricultural soils) on local growth rates and on interactions between two competing microbial species. Interestingly, the complexity of soil spaces and aquatic niches are necessary for supporting a rich microbial diversity and the wide array of microbial functions in unsaturated soils. This project supported collaboration between soil physicists and soil microbiologist that is absolutely essential for making progress in both disciplines. It provided a few basic tools (models, parameterization) for guiding future experiments and for gathering key information necessary for prediction of biological processes in agricultural soils. The project sparked a series of ongoing studies (at DTU and EPFL and in the ARO) into effects of soil hydration dynamics on microbial survival strategy under short term and prolonged desiccation (important for general scientific and agricultural applications).
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Ansari, S. M., E. M. Schetselaar, and J. A. Craven. Three-dimensional magnetotelluric modelling of the Lalor volcanogenic massive-sulfide deposit, Manitoba. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/328003.

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Unconstrained magnetotelluric inversion commonly produces insufficient inherent resolution to image ore-system fluid pathways that were structurally thinned during post-emplacement tectonic activity. To improve the resolution in these complex environments, we synthesized the 3-D magnetotelluric (MT) response for geologically realistic models using a finite-element-based forward-modelling tool with unstructured meshes and applied it to the Lalor volcanogenic massive-sulfide deposit in the Snow Lake mining camp, Manitoba. This new tool is based on mapping interpolated or simulated resistivity values from wireline logs onto unstructured tetrahedral meshes to reflect, with the help of 3-D models obtained from lithostratigraphic and lithofacies drillhole logs, the complexity of the host-rock geological structure. The resulting stochastic model provides a more realistic representation of the heterogeneous spatial distribution of the electric resistivity values around the massive, stringer, and disseminated sulfide ore zones. Both models were combined into one seamless tetrahedral mesh of the resistivity field. To capture the complex resistivity distribution in the geophysical forward model, a finite-element code was developed. Comparative analyses of the forward models with MT data acquired at the Earth's surface show a reasonable agreement that explains the regional variations associated with the host rock geological structure and detects the local anomalies associated with the MT response of the ore zones.
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Lafrancois, Toben, Mark Hove, and Jay Glase. Zebra mussel (Dreissena polymorpha) distribution in Apostle Islands National Lakeshore: SCUBA-based search and removal efforts: 2019–2020. National Park Service, May 2022. http://dx.doi.org/10.36967/nrr-2293376.

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Invasive zebra mussels (Dreissena polymorpha) were first observed in situ at Apostle Islands National Lakeshore (APIS) in 2015. This report builds on 2018 SCUBA surveys and Environmental Protection Agency (EPA) veliger sampling to: 1) determine whether shoals on APIS borders act as sentinel sites to corroborate veliger drift hypotheses about invasion pathways, 2) evaluate ongoing hand-removal of zebra mussels from easily identified structures, and 3) continue efforts to assess native unionid mussel populations, particularly where zebra mussels are also present. Standard catch per unit effort survey methods by SCUBA teams were used to determine the distribution and relative abundance of zebra or quagga mussels (dreissenids) and native mussels (unionids). Zebra mussels were present at densities between 3 and 42 n/diver/hr (number of mussels per diver per hour), while native unionids were present at densities between 5 and 72 n/diver/hr. Shoal surveys (Eagle Island shoal, Sand Island shoal, York Island shoal, Bear Island shoal, Oak Island shoal, and Gull Island shoal) showed zebra mussels were more abundant on the west side of APIS and absent on the easternmost shoal (Gull Island), corroborating veliger work by the EPA that suggested drift from the Twin Ports of Duluth, Minnesota, and Superior, Wisconsin, is one pathway of invasion. Our results support the use of shallow shoals along the periphery of the park as sentinel sites gauging zebra mussel immigration and population dynamics. Zebra mussel densities in the central islands showed no obvious spatial pattern, and this survey cannot determine whether currents or human transport (or both) are invasion vectors. Given the mussels’ continued presence at heavily used mooring areas and docks where there are no zebra mussels on nearby natural features (e.g., Rocky Island dock, Stockton Island mooring areas), our findings are consistent with multiple invasion pathways (drift from the Twin Ports and anthropogenic sources at mooring areas). SCUBA search and removal of zebra mussels from docks was confirmed to be an effective method for significantly lowering the risk of zebra mussels reproducing and dispersing from these locations. We caution that this work is being done on what look like initial invasions at low densities. Repeated removal of zebra mussels by divers reduced numbers to zero at some sites after one year (South Twin docks, Stockton Island NPS docks, and the Ottawa wreck) or decreased numbers by an order of magnitude (Rocky Island docks). Dreissenid densities were more persistent on the Sevona wreck and longer-term work is required to evaluate removal versus recruitment (local and/or veliger drift). Given the size of the wreck, we have tracked detailed survey maps to guide future efforts. Zebra mussels were again observed attached to native mussels near Stockton Island and South Twin Island. Their continued presence on sensitive native species is of concern. Native unionid mussels were more widely distributed in the park than previously known, with new beds found near Oak and Basswood Islands. The work reported here will form the basis for continued efforts to determine the optimal frequency of zebra mussel removal for effective control, as well as evaluate impacts on native species.
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Beiter, Philipp, Walter Musial, Aaron Smith, Levi Kilcher, Rick Damiani, Michael Maness, Senu Sirnivas, et al. A Spatial-Economic Cost-Reduction Pathway Analysis for U.S. Offshore Wind Energy Development from 2015–2030. Office of Scientific and Technical Information (OSTI), September 2016. http://dx.doi.org/10.2172/1324526.

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Fait, Aaron, Grant Cramer, and Avichai Perl. Towards improved grape nutrition and defense: The regulation of stilbene metabolism under drought. United States Department of Agriculture, May 2014. http://dx.doi.org/10.32747/2014.7594398.bard.

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The goals of the present research proposal were to elucidate the physiological and molecular basis of the regulation of stilbene metabolism in grape, against the background of (i) grape metabolic network behavior in response to drought and of (ii) varietal diversity. The specific objectives included the study of the physiology of the response of different grape cultivars to continuous WD; the characterization of the differences and commonalities of gene network topology associated with WD in berry skin across varieties; the study of the metabolic response of developing berries to continuous WD with specific attention to the stilbene compounds; the integration analysis of the omics data generated; the study of isolated drought-associated stress factors on the regulation of stilbene biosynthesis in plantaand in vitro. Background to the topic Grape quality has a complex relationship with water input. Regulated water deficit (WD) is known to improve wine grapes by reducing the vine growth (without affecting fruit yield) and boosting sugar content (Keller et al. 2008). On the other hand, irregular rainfall during the summer can lead to drought-associated damage of fruit developmental process and alter fruit metabolism (Downey et al., 2006; Tarara et al., 2008; Chalmers et al., 792). In areas undergoing desertification, WD is associated with high temperatures. This WD/high temperature synergism can limit the areas of grape cultivation and can damage yields and fruit quality. Grapes and wine are the major source of stilbenes in human nutrition, and multiple stilbene-derived compounds, including isomers, polymers and glycosylated forms, have also been characterized in grapes (Jeandet et al., 2002; Halls and Yu, 2008). Heterologous expression of stilbenesynthase (STS) in a variety of plants has led to an enhanced resistance to pathogens, but in others the association has not been proven (Kobayashi et al., 2000; Soleas et al., 1995). Tomato transgenic plants harboring a grape STS had increased levels of resveratrol, ascorbate, and glutathione at the expense of the anthocyanin pathways (Giovinazzo et al. 2005), further emphasizing the intermingled relation among secondary metabolic pathways. Stilbenes are are induced in green and fleshy parts of the berries by biotic and abiotic elicitors (Chong et al., 2009). As is the case for other classes of secondary metabolites, the biosynthesis of stilbenes is not very well understood, but it is known to be under tight spatial and temporal control, which limits the availability of these compounds from plant sources. Only very few studies have attempted to analyze the effects of different environmental components on stilbene accumulation (Jeandet et al., 1995; Martinez-Ortega et al., 2000). Targeted analyses have generally shown higher levels of resveratrol in the grape skin (induced), in seeded varieties, in varieties of wine grapes, and in dark-skinned varieties (Gatto et al., 2008; summarized by Bavaresco et al., 2009). Yet, the effect of the grape variety and the rootstock on stilbene metabolism has not yet been thoroughly investigated (Bavaresco et al., 2009). The study identified a link between vine hydraulic behavior and physiology of stress with the leaf metabolism, which the PIs believe can eventually lead to the modifications identified in the developing berries that interested the polyphenol metabolism and its regulation during development and under stress. Implications are discussed below.
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Friedman, Haya, Julia Vrebalov, James Giovannoni, and Edna Pesis. Unravelling the Mode of Action of Ripening-Specific MADS-box Genes for Development of Tools to Improve Banana Fruit Shelf-life and Quality. United States Department of Agriculture, January 2010. http://dx.doi.org/10.32747/2010.7592116.bard.

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Fruit deterioration is a consequence of a genetically-determined fruit ripening and senescence programs, in which developmental factors lead to a climacteric rise of ethylene production in ethylene-sensitive fruits such as tomato and banana. Breeding of tomato with extended fruit shelf life involves the incorporation of a mutation in RIN, a MADS-box transcription factor participating in developmental control signalling of ripening. The RIN mode of action is not fully understood, and it may be predicted to interact with other MADS-box genes to execute its effects. The overall goal of this study was to demonstrate conservation of ripening control functions between banana and tomato and thus, the potential to genetically extend shelf-life in banana based on tools developed in tomato. The specific objectives were: 1. To increase the collection of potential RIN-like genes from banana; 2. To verify their action as developmental regulators; 3. To elucidate MADS-box gene mode of action in ripening control; 4. To create transgenic banana plants that express low levels of endogenous Le-RIN- like, MaMADS- gene(s). We have conducted experiments in banana as well as in tomato. In tomato we have carried out the transformation of the tomato rin mutant with the MaMADS1 and MaMADS2 banana genes. We have also developed a number of domain swap constructs to functionally examine the ripening-specific aspects of the RIN gene. Our results show the RIN-C terminal region is essential for the gene to function in the ripening signalling pathway. We have further explored the tomato genome databases and recovered an additional MADS-box gene necessary for fruit ripening. This gene has been previously termed TAGL1 but has not been functionally characterized in transgenic plants. TAGL1 is induced during ripening and we have shown via RNAi repression that it is necessary for both fleshy fruit expansion and subsequent ripening. In banana we have cloned the full length of six MaMADS box genes from banana and determined their spatial and temporal expression patterns. We have created antibodies to MaMADS2 and initiated ChI assay. We have created four types of transgenic banana plants designed to reduce the levels of two of the MaMADS box genes. Our results show that the MaMADS-box genes expression in banana is dynamically changing after harvest and most of them are induced at the onset of the climacteric peak. Most likely, different MaMADS box genes are active in the pulp and peel and they are differently affected by ethylene. Only the MaMADS2 box gene expression is not affected by ethylene indicating that this gene might act upstream to the ethylene response pathway. The complementation analysis in tomato revealed that neither MaMADS1 nor MaMADS2 complement the rin mutation suggesting that they have functionally diverged sufficiently to not be able to interact in the context of the tomato ripening regulatory machinery. The developmental signalling pathways controlling ripening in banana and tomato are not identical and/or have diverged through evolution. Nevertheless, at least the genes MaMADS1 and MaMADS2 constitute part of the developmental control of ripening in banana, since transgenic banana plants with reduced levels of these genes are delayed in ripening. The detailed effect on peel and pulp, of these transgenic plants is underway. So far, these transgenic bananas can respond to exogenous ethylene, and they seem to ripen normally. The response to ethylene suggest that in banana the developmental pathway of ripening is different than that in tomato, because rin tomatoes do not ripen in response to exogenous ethylene, although they harbor the ethylene response capability This study has a major contribution both in scientific and agricultural aspects. Scientifically, it establishes the role of MaMADS box genes in a different crop-the banana. The developmental ripening pathway in banana is similar, but yet different from that of the model plant tomato and one of the major differences is related to ethylene effect on this pathway in banana. In addition, we have shown that different components of the MaMADS-box genes are employed in peel and pulp. The transgenic banana plants created can help to further study the ripening control in banana. An important and practical outcome of this project is that we have created several banana transgenic plants with fruit of extended shelf life. These bananas clearly demonstrate the potential of MaMADS gene control for extending shelf-life, enhancing fruit quality, increasing yield in export systems and for improving food security in areas where Musaspecies are staple food crops.
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