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The following results are related to Canada. Are you interested to view more results? Visit OpenAIRE - Explore.
28 Projects, page 1 of 3

  • Canada
  • UK Research and Innovation
  • UKRI|BBSRC

10
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  • Funder: UKRI Project Code: BB/W010720/1
    Funder Contribution: 3,000 GBP
    Partners: UBC, IFR

    Canada

  • Funder: UKRI Project Code: BB/E011632/1
    Funder Contribution: 379,127 GBP
    Partners: Dalhousie University, University of Glasgow

    The cells that make up every organism are delicate and intricate machines that must carry out many complex tasks to stay alive. The single celled fungus, the budding yeast, although modest in size, shares with our cells many of these intricate mechanisms. Yeast has the huge advantage over humans in scientific research: it is relatively easy and cheap to study. Many of the insights gained into how yeast cells work apply, in one form or another, to other organisms, including ourselves. Among the key tasks shared between yeast and human cells is the ability to grow bigger without bursting. Another is to survive changes in the immediate environment that threaten lysis (bursting), such as changes in temperature or nasty chemicals. Yeast possesses one main system that senses a variety of threats to the cell's integrity and responds so as to maintain that integrity (and thereby keep the cell alive) - the cell wall integrity (CWI) pathway. Many of the components of this system are shared with humans but some are not - these latter may be a fungus' Achilles' heel, to which drugs could be developed that cause fungal cells (many pathogenic) to blow up (die) leaving human cells undisturbed. The CWI pathway is worth understanding. In addition, the CWI pathway presents scientific puzzles that challenge our understanding of how living systems work. Multiple signals feed into this pathway, and the pathway can activate a variety of distinct responses: how can one pathway integrate many inputs and 'decide' to make a sensible response? Key regulators of the CWI pathway are proteins called GEFs. CWI-GEFs appear to come in two distinct flavours that appear to perform distinct roles in activating the pathway. In this proposal, we seek to better understand how these GEFs are regulated, how they differ from each other both structurally and functionally and how information is processed by these GEFs to affect CWI outputs in the appropriate way. We hope to better understand how the complex and important CWI pathway is regulated.

  • Funder: UKRI Project Code: BB/P02582X/1
    Funder Contribution: 30,612 GBP
    Partners: SFU, University of Aberdeen, UNIVERSITY OF VICTORIA, MUN

    Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

  • Funder: UKRI Project Code: BB/W018624/1
    Funder Contribution: 19,737 GBP
    Partners: University of Saskatchewan, UoC, Aberystwyth University, JIC, The Alan Turing Institute

    Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

  • Funder: UKRI Project Code: BB/L007320/1
    Funder Contribution: 346,292 GBP
    Partners: Max Planck, DuPont (Global), University of Alberta, CNRC, Cardiff University

    Oil crops are one of the most important agricultural commodities. In the U.K. (and Northern Europe and Canada) oilseed rape is the dominant oil crop and worldwide it accounts for about 12% of the total oil and fat production. There is an increasing demand for plant oils not only for human food and animal feed but also as renewable sources of chemicals and biofuels. This increased demand has shown a doubling every 8 years over the last four decades and is likely to continue at, at least, this rate in the future. With a limitation on agricultural land, the main way to increase production is to increase yields. This can be achieved by conventional breeding but, in the future, significant enhancements will need genetic manipulation. The latter technique will also allow specific modification of the oil product to be achieved. In order for informed genetic manipulation to take place, a thorough knowledge of the biosynthesis of plant oils is needed. Crucially, this would include how regulation of oil quality and quantity is controlled. The synthesis of storage oil in plant seeds is analogous to a factory production line, where the supply of raw materials, manufacture of components and final assembly can all potentially limit the rate of production. Recently, we made a first experimental study of overall regulation of storage oil accumulation in oilseed rape, which we analysed by a mathematical method called flux control analysis. This showed that it is the final assembly that is the most important limitation on the biosynthetic process. The assembly process requires several enzyme steps and we have already highlighted one of these, diacylglycerol acyltransferase (DGAT), as being a significant controlling factor. We now wish to examine enzymes, other than DGAT, involved in storage lipid assembly and in supply of component parts. This will enable us to quantify the limitations imposed by different enzymes of the pathway and, furthermore, will provide information to underpin logical steps in genetic manipulation leading to plants with increased oil synthesis and storage capabilities. We will use rape plants where the activity of individual enzymes in the biosynthetic pathway have been changed and quantify the effects on overall oil accumulation. To begin with we will use existing transgenic oilseed rape, with increased enzyme levels, where increases in oil yields have been noted; these are available from our collaborators (Canada, Germany). For enzymes where there are no current transgenic plants available, we will make these and carry out similar analyses. Although our primary focus is on enzymes that increase oil yields, we will also examine the contribution the enzyme phospholipid: diacylglycerol acyltransferase (PDAT) makes to lipid production because this enzyme controls the accumulation of unsaturated oil, which has important dietary implications. In the analogous model plant Arabidopsis, PDAT and DGAT are both important during oil production. Once we have assembled data from these transgenic plants we will have a much better idea of the control of lipid production in oilseed rape. Our quantitative measurements will provide specific targets for future crop improvements. In addition, because we will be monitoring oil yields as well as flux control we will be able to correlate these two measures. Moreover, plants manipulated with multiple genes (gene stacking) will reveal if there are synergistic effects of such strategies. Because no one has yet defined quantitatively the oil synthesis pathway in crops, data produced in the project will have a fundamental impact in basic science. By combining the expertise of three important U.K. labs. with our world-leading international collaborators, this cross-disciplinary project will ensure a significant advance in knowledge of direct application to agriculture.

  • Funder: UKRI Project Code: BB/W018721/1
    Funder Contribution: 51,020 GBP
    Partners: PhaSE Biolabs Ltd, NTU, Metabolic Explorer, University of Toronto, LanzaTech, Celtic Renewables Ltd

    Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

  • Funder: UKRI Project Code: BB/F015615/1
    Funder Contribution: 715,310 GBP
    Partners: La Trobe University, USGS Patuxent Wildlife Research Center, UBC, BU

    We propose to undertake the first detailed scientific studies into the flight biology, migratory physiology and energetics of bar-headed geese in the wild using the latest electronic dataloggering technology. Ultimately, we will address the question of where are the limits to sustainable avian flight performance at high altitudes and what is the effect of body mass? In particular, how do larger species cope during flight with the combined effects of reduced air density, low oxygen availability and decreased temperature? Only a few species of larger birds are thought to be able to sustain long periods of flapping flight at high altitudes and these have received little study. The best known species is the bar-headed goose (Anser indicus) which performs one of the most physically challenging and impressive avian migrations by flying twice a year through the high plateau areas of the Himalayas, with some populations travelling between high altitude breeding grounds in China and lowland wintering areas in northern India. Despite their extraordinary flight performance and immensely interesting physiology and behaviour, neither the aerodynamic or physiological adaptations required to perform such feats are well understood. We will use miniature GPS tracking devices to provide detailed position and altitude during the flights so that we can identify their route in relation to the geographical topography and environmental conditions. This will also allow us to measure their rates of climb when migrating through the mountains. The bar-headed goose migration is exceptional for such a large bird as aerodynamic and biomechanical considerations suggest that as birds increase in body mass flight performance should deteriorate. Thus, bar-headed geese with a body mass of around 2.5 to 3.5 kg should only have a marginal physical capacity to sustain climbing flight even at sea level, and this ability should get worse as altitude increases due to the decrease in air density. By using 3-axis accelerometry we will be able to calculate the net aerodynamic forces acting on the body of the birds and monitor any changes in wingbeat frequency and relative wingbeat amplitude in response to changes in altitude and during the climbing flight. Their flights are also remarkable due to the physiological difficulties of sustaining any kind of exercise while coping with the harsh environmental conditions of the Tibetan plateau, especially the low ambient temperatures and the reduced availability of oxygen. Nevertheless, bar-headed geese have been recorded to fly between 4,000 m and 8,000 m, where partial pressures of oxygen are around 50% that of sea-level and temperatures can be as low as -20 C. We will measure the heart beat frequency of the birds during flights at different altitudes and estimate the maximum efforts expended during climbing flights in relation to their maximum expected capabilities. To place the remarkable migratory flights of the bar-headed goose in context, some 90% of avian migrations over land occur below 2000 m and the majority below 1000 m, which is well below the level of some of the main breeding lakes of the bar-headed goose (4,200 m to 4,718 m). We anticipate that the geographical barrier of the Himalayas should force these relatively large birds to fly close to the limits of their cardiac, muscular, respiratory and aerodynamic abilities. Indeed, this proposal will address the hypothesis that these migratory climbing flights may only by possible with the assistance of favourable up currents of air due to weather fronts or topographical reflections. Recent developments in electronic dataloggers now make it possible to measure both physical and physiological aspects of flight behaviour in free-flying birds rather than in animals constrained by captive conditions. Access to free-flying bar-headed geese would provide a unique opportunity to study the flight biology of a relatively large bird pushed to the extremes of its performance.

  • Funder: UKRI Project Code: BB/J004197/1
    Funder Contribution: 1,988 GBP
    Partners: UBC, University of Bristol

    Canada

  • Funder: UKRI Project Code: BB/F004354/1
    Funder Contribution: 797,504 GBP
    Partners: Durham University, Arkema Ltd, FUCHS Lubricants UK Plc, Linnaeus Plant Sciences (Canada)

    The main aim of this proposal is to produce ricinoleic acid in plants at a high level allowing it to be used as a renewable raw material for the manufacture of: [1] Nylon N-11 - which is a main component of hydraulic fluid pipes in engines. [2]Lubricants to replace mineral based oils. These have applications in the areas of gear/transmission and hydraulics. Additionally we wish to investigate: [1]The metabolic assembly and chanelling/compartmentalisation of the ricinoleic acid/triacylglycerol pathway in plants [2] Explore the possibilities of using ricinoleic acid as a wider feedstock for production of novel polymers and other applications. [3] Development of B.carinata as an industrial oil crop for UK.

  • Funder: UKRI Project Code: BB/G004803/1
    Funder Contribution: 272,247 GBP
    Partners: University of Stirling, York University Canada

    The human brain uses small differences between the images reaching our two eyes to perceive the three-dimensional shape of the world around us. In order to detect these differences, known as binocular disparities, the brain must find points in one eye's image that match to points in the other eye's image. However, for any single point in an image, the brain is often forced to choose between multiple matches. The problem of finding the correct match from amongst these alternatives is known as the correspondence problem. This problem can be simplified by making assumptions about the typical shape of objects in the world, and by finding matches between different kinds of basic tokens. For example, the number of alternative solutions to the correspondence problem will be far greater if the brain uses single points of light as a basic token for matching, compared to a case where a more complex token, such as a shape or texture, is used. Furthermore, these complex tokens can be based on different kinds of information. The research proposed here examines how matching tokens based on different forms of information can be used by the brain to solve the correspondence problem. Specifically, we shall examine how the brain may solve the correspondence problem using tokens derived from mechanisms sensitive to changes in light and dark (i.e. changes in luminance), and mechanisms sensitive to changes in texture. We shall develop computer simulations of the processes used by the brain to solve the correspondence problem and measure disparity. These simulations will show how the use of different basic information for matching (i.e. changes in luminance and changes in texture) can change the nature of the correspondence problem. We shall discover whether the combined use of texture- and luminance-based matching tokens can help to reduce noise in disparity measurement and whether the use of texture-based matching can reduce the number of available solutions to the correspondence problem. Following this, we shall examine whether the brain actually makes use of the combined information available from texture and luminance. By presenting human participants with images containing disparities defined by both texture and luminance, we shall establish whether the human brain actually uses these different types of information to reduce noise, or improve its ability to solve the correspondence problem. In addition to examining whether using luminance and texture information to measure disparity helps the brain to reduce noise and simplify the correspondence problem, we shall also examine whether sensitivity to these different types of image information can help the brain to detect discontinuities in depth. Depth discontinuities arise when depth changes sharply across a small area, such as when an observer's view of one object is partially obscured by another object in front of it. The processing of texture-based disparities may help in the detection of depth discontinuities since different objects often differ in texture. We shall establish whether information of this kind may actually be useful in the detection of depth discontinuities, and whether human observers actually use this information.

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The following results are related to Canada. Are you interested to view more results? Visit OpenAIRE - Explore.
28 Projects, page 1 of 3
  • Funder: UKRI Project Code: BB/W010720/1
    Funder Contribution: 3,000 GBP
    Partners: UBC, IFR

    Canada

  • Funder: UKRI Project Code: BB/E011632/1
    Funder Contribution: 379,127 GBP
    Partners: Dalhousie University, University of Glasgow

    The cells that make up every organism are delicate and intricate machines that must carry out many complex tasks to stay alive. The single celled fungus, the budding yeast, although modest in size, shares with our cells many of these intricate mechanisms. Yeast has the huge advantage over humans in scientific research: it is relatively easy and cheap to study. Many of the insights gained into how yeast cells work apply, in one form or another, to other organisms, including ourselves. Among the key tasks shared between yeast and human cells is the ability to grow bigger without bursting. Another is to survive changes in the immediate environment that threaten lysis (bursting), such as changes in temperature or nasty chemicals. Yeast possesses one main system that senses a variety of threats to the cell's integrity and responds so as to maintain that integrity (and thereby keep the cell alive) - the cell wall integrity (CWI) pathway. Many of the components of this system are shared with humans but some are not - these latter may be a fungus' Achilles' heel, to which drugs could be developed that cause fungal cells (many pathogenic) to blow up (die) leaving human cells undisturbed. The CWI pathway is worth understanding. In addition, the CWI pathway presents scientific puzzles that challenge our understanding of how living systems work. Multiple signals feed into this pathway, and the pathway can activate a variety of distinct responses: how can one pathway integrate many inputs and 'decide' to make a sensible response? Key regulators of the CWI pathway are proteins called GEFs. CWI-GEFs appear to come in two distinct flavours that appear to perform distinct roles in activating the pathway. In this proposal, we seek to better understand how these GEFs are regulated, how they differ from each other both structurally and functionally and how information is processed by these GEFs to affect CWI outputs in the appropriate way. We hope to better understand how the complex and important CWI pathway is regulated.

  • Funder: UKRI Project Code: BB/P02582X/1
    Funder Contribution: 30,612 GBP
    Partners: SFU, University of Aberdeen, UNIVERSITY OF VICTORIA, MUN

    Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

  • Funder: UKRI Project Code: BB/W018624/1
    Funder Contribution: 19,737 GBP
    Partners: University of Saskatchewan, UoC, Aberystwyth University, JIC, The Alan Turing Institute

    Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

  • Funder: UKRI Project Code: BB/L007320/1
    Funder Contribution: 346,292 GBP
    Partners: Max Planck, DuPont (Global), University of Alberta, CNRC, Cardiff University

    Oil crops are one of the most important agricultural commodities. In the U.K. (and Northern Europe and Canada) oilseed rape is the dominant oil crop and worldwide it accounts for about 12% of the total oil and fat production. There is an increasing demand for plant oils not only for human food and animal feed but also as renewable sources of chemicals and biofuels. This increased demand has shown a doubling every 8 years over the last four decades and is likely to continue at, at least, this rate in the future. With a limitation on agricultural land, the main way to increase production is to increase yields. This can be achieved by conventional breeding but, in the future, significant enhancements will need genetic manipulation. The latter technique will also allow specific modification of the oil product to be achieved. In order for informed genetic manipulation to take place, a thorough knowledge of the biosynthesis of plant oils is needed. Crucially, this would include how regulation of oil quality and quantity is controlled. The synthesis of storage oil in plant seeds is analogous to a factory production line, where the supply of raw materials, manufacture of components and final assembly can all potentially limit the rate of production. Recently, we made a first experimental study of overall regulation of storage oil accumulation in oilseed rape, which we analysed by a mathematical method called flux control analysis. This showed that it is the final assembly that is the most important limitation on the biosynthetic process. The assembly process requires several enzyme steps and we have already highlighted one of these, diacylglycerol acyltransferase (DGAT), as being a significant controlling factor. We now wish to examine enzymes, other than DGAT, involved in storage lipid assembly and in supply of component parts. This will enable us to quantify the limitations imposed by different enzymes of the pathway and, furthermore, will provide information to underpin logical steps in genetic manipulation leading to plants with increased oil synthesis and storage capabilities. We will use rape plants where the activity of individual enzymes in the biosynthetic pathway have been changed and quantify the effects on overall oil accumulation. To begin with we will use existing transgenic oilseed rape, with increased enzyme levels, where increases in oil yields have been noted; these are available from our collaborators (Canada, Germany). For enzymes where there are no current transgenic plants available, we will make these and carry out similar analyses. Although our primary focus is on enzymes that increase oil yields, we will also examine the contribution the enzyme phospholipid: diacylglycerol acyltransferase (PDAT) makes to lipid production because this enzyme controls the accumulation of unsaturated oil, which has important dietary implications. In the analogous model plant Arabidopsis, PDAT and DGAT are both important during oil production. Once we have assembled data from these transgenic plants we will have a much better idea of the control of lipid production in oilseed rape. Our quantitative measurements will provide specific targets for future crop improvements. In addition, because we will be monitoring oil yields as well as flux control we will be able to correlate these two measures. Moreover, plants manipulated with multiple genes (gene stacking) will reveal if there are synergistic effects of such strategies. Because no one has yet defined quantitatively the oil synthesis pathway in crops, data produced in the project will have a fundamental impact in basic science. By combining the expertise of three important U.K. labs. with our world-leading international collaborators, this cross-disciplinary project will ensure a significant advance in knowledge of direct application to agriculture.

  • Funder: UKRI Project Code: BB/W018721/1
    Funder Contribution: 51,020 GBP
    Partners: PhaSE Biolabs Ltd, NTU, Metabolic Explorer, University of Toronto, LanzaTech, Celtic Renewables Ltd

    Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

  • Funder: UKRI Project Code: BB/F015615/1
    Funder Contribution: 715,310 GBP
    Partners: La Trobe University, USGS Patuxent Wildlife Research Center, UBC, BU

    We propose to undertake the first detailed scientific studies into the flight biology, migratory physiology and energetics of bar-headed geese in the wild using the latest electronic dataloggering technology. Ultimately, we will address the question of where are the limits to sustainable avian flight performance at high altitudes and what is the effect of body mass? In particular, how do larger species cope during flight with the combined effects of reduced air density, low oxygen availability and decreased temperature? Only a few species of larger birds are thought to be able to sustain long periods of flapping flight at high altitudes and these have received little study. The best known species is the bar-headed goose (Anser indicus) which performs one of the most physically challenging and impressive avian migrations by flying twice a year through the high plateau areas of the Himalayas, with some populations travelling between high altitude breeding grounds in China and lowland wintering areas in northern India. Despite their extraordinary flight performance and immensely interesting physiology and behaviour, neither the aerodynamic or physiological adaptations required to perform such feats are well understood. We will use miniature GPS tracking devices to provide detailed position and altitude during the flights so that we can identify their route in relation to the geographical topography and environmental conditions. This will also allow us to measure their rates of climb when migrating through the mountains. The bar-headed goose migration is exceptional for such a large bird as aerodynamic and biomechanical considerations suggest that as birds increase in body mass flight performance should deteriorate. Thus, bar-headed geese with a body mass of around 2.5 to 3.5 kg should only have a marginal physical capacity to sustain climbing flight even at sea level, and this ability should get worse as altitude increases due to the decrease in air density. By using 3-axis accelerometry we will be able to calculate the net aerodynamic forces acting on the body of the birds and monitor any changes in wingbeat frequency and relative wingbeat amplitude in response to changes in altitude and during the climbing flight. Their flights are also remarkable due to the physiological difficulties of sustaining any kind of exercise while coping with the harsh environmental conditions of the Tibetan plateau, especially the low ambient temperatures and the reduced availability of oxygen. Nevertheless, bar-headed geese have been recorded to fly between 4,000 m and 8,000 m, where partial pressures of oxygen are around 50% that of sea-level and temperatures can be as low as -20 C. We will measure the heart beat frequency of the birds during flights at different altitudes and estimate the maximum efforts expended during climbing flights in relation to their maximum expected capabilities. To place the remarkable migratory flights of the bar-headed goose in context, some 90% of avian migrations over land occur below 2000 m and the majority below 1000 m, which is well below the level of some of the main breeding lakes of the bar-headed goose (4,200 m to 4,718 m). We anticipate that the geographical barrier of the Himalayas should force these relatively large birds to fly close to the limits of their cardiac, muscular, respiratory and aerodynamic abilities. Indeed, this proposal will address the hypothesis that these migratory climbing flights may only by possible with the assistance of favourable up currents of air due to weather fronts or topographical reflections. Recent developments in electronic dataloggers now make it possible to measure both physical and physiological aspects of flight behaviour in free-flying birds rather than in animals constrained by captive conditions. Access to free-flying bar-headed geese would provide a unique opportunity to study the flight biology of a relatively large bird pushed to the extremes of its performance.

  • Funder: UKRI Project Code: BB/J004197/1
    Funder Contribution: 1,988 GBP
    Partners: UBC, University of Bristol

    Canada

  • Funder: UKRI Project Code: BB/F004354/1
    Funder Contribution: 797,504 GBP
    Partners: Durham University, Arkema Ltd, FUCHS Lubricants UK Plc, Linnaeus Plant Sciences (Canada)

    The main aim of this proposal is to produce ricinoleic acid in plants at a high level allowing it to be used as a renewable raw material for the manufacture of: [1] Nylon N-11 - which is a main component of hydraulic fluid pipes in engines. [2]Lubricants to replace mineral based oils. These have applications in the areas of gear/transmission and hydraulics. Additionally we wish to investigate: [1]The metabolic assembly and chanelling/compartmentalisation of the ricinoleic acid/triacylglycerol pathway in plants [2] Explore the possibilities of using ricinoleic acid as a wider feedstock for production of novel polymers and other applications. [3] Development of B.carinata as an industrial oil crop for UK.

  • Funder: UKRI Project Code: BB/G004803/1
    Funder Contribution: 272,247 GBP
    Partners: University of Stirling, York University Canada

    The human brain uses small differences between the images reaching our two eyes to perceive the three-dimensional shape of the world around us. In order to detect these differences, known as binocular disparities, the brain must find points in one eye's image that match to points in the other eye's image. However, for any single point in an image, the brain is often forced to choose between multiple matches. The problem of finding the correct match from amongst these alternatives is known as the correspondence problem. This problem can be simplified by making assumptions about the typical shape of objects in the world, and by finding matches between different kinds of basic tokens. For example, the number of alternative solutions to the correspondence problem will be far greater if the brain uses single points of light as a basic token for matching, compared to a case where a more complex token, such as a shape or texture, is used. Furthermore, these complex tokens can be based on different kinds of information. The research proposed here examines how matching tokens based on different forms of information can be used by the brain to solve the correspondence problem. Specifically, we shall examine how the brain may solve the correspondence problem using tokens derived from mechanisms sensitive to changes in light and dark (i.e. changes in luminance), and mechanisms sensitive to changes in texture. We shall develop computer simulations of the processes used by the brain to solve the correspondence problem and measure disparity. These simulations will show how the use of different basic information for matching (i.e. changes in luminance and changes in texture) can change the nature of the correspondence problem. We shall discover whether the combined use of texture- and luminance-based matching tokens can help to reduce noise in disparity measurement and whether the use of texture-based matching can reduce the number of available solutions to the correspondence problem. Following this, we shall examine whether the brain actually makes use of the combined information available from texture and luminance. By presenting human participants with images containing disparities defined by both texture and luminance, we shall establish whether the human brain actually uses these different types of information to reduce noise, or improve its ability to solve the correspondence problem. In addition to examining whether using luminance and texture information to measure disparity helps the brain to reduce noise and simplify the correspondence problem, we shall also examine whether sensitivity to these different types of image information can help the brain to detect discontinuities in depth. Depth discontinuities arise when depth changes sharply across a small area, such as when an observer's view of one object is partially obscured by another object in front of it. The processing of texture-based disparities may help in the detection of depth discontinuities since different objects often differ in texture. We shall establish whether information of this kind may actually be useful in the detection of depth discontinuities, and whether human observers actually use this information.