Morphological Units Research Articles

OP28.01: Pilot study comparing ex-vivo HREM imaging and in-vivo 4DHRTV ultrasound of the first trimester human fetal heart

H. M. Gardiner1, H. Matsui1, L. Gindes2, M. Wiechec1, T. Mohun3, S. Y. Ho4, R. Achiron2 1IRDB, Imperial College, London, United Kingdom; 2Department of Obstetrics and Gynecology, Sheba Medical Center, Tel-Aviv, Israel; 3Division of Developmental Biology, National Institute of Medical Research, London, United Kingdom; 4Cardiac Morphology Unit, National Heart and Lung Institute, London, United Kingdom

A new method to identify the fluvial regimes used by spawning salmonids

Basin physiography and fluvial processes structure the availability of salmonid spawning habitat in river networks. However, methods that allow us to explicitly link hydrologic and geomorphic processes to spatial patterns of spawning at scales relevant to management are limited. Here we present a method that can be used to link the abundance of spawning salmonids to fluvial processes at the mesoscale. We show that the frequency of spawning activity at individual morphological units (riffles, pools, runs) is quantitatively related to a number of fluvial parameters. Of these, bankfull excess shear stress (τxs) was the best predictor of spawning frequency. Results suggest that τxs can be used to represent the fluvial regimes that spawning salmon are responsive to as well as to assess the likely impacts of altered flow regimes.

Assessment of morphological changes induced by flow and flood pulses in a gravel bed braided river: The Tagliamento River (Italy)

Large gravel-bed braided rivers show a highly dynamic evolution, where even moderate flow pulses can produce significant morphological adjustment. An estimation of network variations is needed by river authorities as well as by ecologists for better managing river ecosystems. However, few field investigations have been performed to measure the effect of unsteady discharges in braided rivers. In this paper we report on the morphological changes induced by six different floods in a 1-km-long reach of the Tagliamento River, Italy. Topographic surveys were performed after each significant flood, and an automatic digital camera continuously monitored the planimetric configuration. Repeated measurements of cross section profiles allowed the quantification of the transported sediments volume and, in particular, provided a basis to estimate the percentage of the floodplain subject to morphological evolution. Data analysis showed a good relationship between peak flow level, active width, and mean bed level changes. Similarly, lateral channel shifting is likely to increase for larger floods. Monitoring of a range of discharges up to bankfull conditions revealed a fundamental difference between flow pulses (events on the average occurring one or more times per year) and flood pulses (with a return period larger than two years). The morphological evolution in the former case is mainly limited to a few active branches and is locally driven by bank erosion at the bend apex. On the other hand, larger floods induce a complete reworking of the network configuration, where bifurcations and confluences play a crucial role. Single morphological units (like branches, nodes, bars) are no longer recognizable after this type of event. Braided rivers are therefore characterized by the occurrence of two different spatial and temporal scales that force the ecosystem dynamics.

Observations on sediment mobility in a large gravel-bed river

This study investigates sediment mobility in a large gravel-bed river (Tagliamento River, northeastern Italy). Field data were used to identify the morphological effectiveness of a range of flows (floods with recurrence interval < 1 to 3.5 year) and for a detailed analysis of the partial transport condition. The analyses were carried out on three cross sections where a number of areas representative of different morphological units (main and secondary channels, low and high bars, islands) were painted. Grain size of the painted area was measured using a photographic method. Monitoring of bed mobility during the study period supplied new photographs of the painted areas, measurements of size and travel distance of the mobilized particles, and estimate of flow depth after each flood event. Our analyses have shown that with dimensionless shear stress around 0.073 (17 N m − 2), the morphological effect over the painted areas was primarily partial transport; while with stresses > 0.1 (25 N m − 2), the bed experienced full mobility, i.e., all the painted particles were transported or totally buried. Full sediment mobility was observed on lower morphological units (i.e., main and secondary channels) under floods with very high frequency ( RI < 1 y), whereas on the low bars full mobility occurred under floods with a recurrence interval slightly > 1 year. Instead, fine deposition and partial transport conditions were observed on the higher bars even after the largest of the monitored floods ( RI = 3.5 y). The analysis of the partial transport condition relies on more than 3500 measurements of particle travel distance (travel distances range from a few centimetres up to 22 m). The transported particles were generally finer than the painted sediments, and the analysis of the sediment transport ratio revealed that partial transport occurred under equal-mobility conditions for particles finer than 32 mm and under size-selective mobility for coarser fractions. This appears to be corroborated (for D < 32 mm) by the insensitiveness of particle transport distance to particle sizes, even if the exponent (≈ 1) of the relationship between the dimensionless shear stress and the maximum transported diameter would suggest that all fractions are transported under equal-mobility conditions.

Caesium-137 in sandy sediments of the River Loire (France): Assessment of an alluvial island evolving over the last 50 years

Recent sedimentological and morphological evolution of an island in the River Loire (France) was investigated using the 137Cs method. This study describes the morphological adjustment of the island in the last 50 years, which corresponds to the increased bed incision of this sandy, multiple-channel environment because of, among other things, the increase in sediment extraction up to 1995. The results show that some 137Cs can be retained by sandy particles, potentially in clay minerals forming weathering features included in detrital sand grains. From a morphological perspective, significant lateral erosion can be observed in the upstream part of the island, while a weak lateral accretion occurs in its downstream section. Data about 137Cs and aerial photographs show that the morphology of the island margins has undergone significant changes leading to a lateral migration, while the centre of the island has remained relatively stable or is slowly eroding. The migration of the island depends on: (1) the withdrawal of inherited preincision morphological units, such as levees, or the development of new units, such as a channel shelf; (2) water and sediment supply from surrounding channels during flood events; (3) preferential sediment trapping (20 mm year − 1 ) from the presence of riparian vegetation on the bank of the secondary channel that is subject to narrowing. The sedimentological and morphological response of the island in the context of incision of the Loire river bed is expressed mainly by lateral migration and secondarily by a low vertical adjustment.

The relations between ‘standard’ fluvial habitat variables and turbulent flow at multiple scales in morphological units of a gravel‐bed river

AbstractFluvial fish habitat is often characterized by highly turbulent flow conditions. Several laboratory experiments suggest that unpredictable turbulent fluctuations can increase the swimming energy costs of fish. At the scale of fish habitat models, it can be hypothesized that turbulence can be captured by the combined effects of the standard habitat variables: depth, velocity and substrate. However, recent studies conducted at the reach scale suggest that turbulent properties are more controlled by the large‐scale bed morphology than by individual roughness elements. In this study, we investigate the spatial structure of turbulent flow and the potential relationships between ‘standard’ habitat variables and turbulent flow properties in pools and riffles of a shallow gravel‐bed river. The study explores these relations at multiple spatial scales. Mean turbulent properties and turbulent flow structures statistics were computed from 1932 near bed velocity time series sampled with acoustic Doppler velocimeters on a regular grid in four morphological units (two pools and two riffles) presenting a gradient of complexity. We used a novel multivariate variation partitioning analysis involving principal coordinates of neighbour matrices (PCNM) to partition turbulent flow properties into six significant spatial scales (VF: 0.35, F: 0.75, M: 1.25, L: 2, XL: 2.5 and XXL: 3 m). Between 45 and 70% of the variance of the turbulent flow properties were explained by the spatial PCNM. In the four units, turbulent properties exhibited a spatial dependence across the entire range of scales. However, the proportion of variation explained by the larger‐scaled PCNMs was higher in the most homogeneous units. In general, the spatial dependence of turbulent flow was lower in the riffles than in the pools, where the mean flow velocity was slower. The capacity of ‘standard’ fish habitat variables to explain turbulent properties was relatively low, especially in the smaller scales, but varied greatly between the units. From a practical point of view, this level of complexity suggests that turbulence should be considered as a ‘distinct’ ecological variable within the range of spatial scales included in this study. Further research should attempt to link the spatial scales of turbulent flow variability to benthic organism patchiness and fish habitat use. Copyright © 2009 John Wiley &amp; Sons, Ltd.

Riffle-pool maintenance and flow convergence routing observed on a large gravel-bed river

Geomorphologists have studied and debated over the processes responsible for natural riffle-pool maintenance for decades. Most studies have focused on small wadable rivers, but they lack much description of overbank flood conditions or a spatially explicit characterization of morphodynamics. In this study, 1-m horizontal resolution digital elevation models were collected from a riffle-pool-run sequence before and after an overbank flood with a 7.7-year recurrence interval on the relatively large gravel-bed lower Yuba River, California. Digital elevation model differencing was used to quantify the magnitude and pattern of flood-induced morphodynamic change. Cross section based analysis and two-dimensional hydrodynamic modeling of flows ranging from 0.147 to 7.63 times bankful discharge were completed to evaluate the hydraulic mechanisms responsible for the observed topographic changes. One key finding was that riffle-pool relief increased by 0.42 m, confirming the occurrence of natural hydrogeomorphic maintenance. Spatially complex patterns of scour and deposition exceeding 0.15 m at the scale of subwidth morphological units were reasonably predicted by the two-dimensional mechanistic model that accounts for convective acceleration. The one-dimensional cross section based method underperformed the two-dimensional model significantly. Consequently, multiple scales of channel non-uniformity and a dynamic flow regime caused the observed maintenance of the pool-riffle morphology through the mechanism of “flow convergence routing” proposed by MacWilliams et al. [MacWilliams, M.L., Wheaton, J.M., Pasternack, G.B., Kitanidis, P.K., Street, R.L., 2006. The flow convergence-routing hypothesis for riffle-pool maintenance in alluvial rivers. Water Resources Research 42, W10427, doi:10.1029/2005WR004391].

Defining the CT Angiography ‘Spot Sign’ in Primary Intracerebral Hemorrhage

The computed tomogram angiography (CTA) 'spot sign' describes foci of intralesional enhancement associated with hematoma expansion in primary intracerebral hemorrhage patients. A consistent radiological definition is required for two proposed recombinant Factor VIIa trials planning patient dichotomization according to 'spot sign' presence or absence. We propose radiological criteria for diagnosis of the CTA 'spot sign' and describe different morphological patterns. A prospective cohort of 36 consecutive patients presenting with primary intracerebral hemorrhage (ICH) were enrolled in a multicenter collaborative study, and have been included for the present analysis. Three reviewers analyzed the CTA studies in a blinded protocol. Analysis of specific ICH and 'spot sign' features was performed including prevalence, number, size, location, morphology and Hounsfield unit density. Twelve of thirty-six patients (33%) demonstrated a total of 19 enhancing foci consistent with the CTA 'spot sign'. Mean maximal axial 'spot sign' dimension was 3.7 +/- 2.2 mm and mean density was 216 +/- 57.7 HU. No significant differences in age or blood pressure (p = 0.7), glucose (p = 0.9), INR/PTT (p = 0.3 and 0.4) or hematoma location (p = 0.3) were demonstrated between patients with or without the 'spot sign'. Consensus definition and classification criteria for the CTA 'spot sign' are proposed. The 'spot sign' is defined as spot-like and/or serpiginous foci of enhancement, within the margin of a parenchymal hematoma without connection to outside vessels. The 'spot sign' is greater than 1.5 mm in maximal dimension and has a Hounsfield unit density at least double that of background hematoma density.

Evolusi Bentuklahan daerah Manado dan sekitarnya, Sulawesi Utara

http://dx.doi.org/10.17014/ijog.vol4no2.20096Landform evolusion in Manado region has been strongly influenced by tectonic activities beside marine and volcanic ones. Based on surface and subsurface (shallow drilling) geological data, landform evolution of the studied areas can be grouped into four morphological environment units consisting of nine environment sets of morphology, these are: ( a). flood basin, ( b). tidal beach, (c).swamp, (d). river channel, (e).volcanic eruption, (f). flood basin influenced by water, (g).coastal/shore, (h). near shore, and (i). offshore. Collumnar analyses on nine drilling data show that the landform evolution history in the Manado region has undergone more than one tectonic event and three eruptions, proved by the presence of discontinuities on morphological environment units and composition, vertically.

A grammar of Mantauran (Rukai) (review)

Reviewed by: A grammar of Mantauran (Rukai) Lawrence A. Reid Elizabeth Zeitoun. 2007. A grammar of Mantauran (Rukai). Taipei: Institute of Linguistics, Academia Sinica. Language and Linguistics Monograph Series A4-2. xviii + 551 pp. ISBN 978-986-01-1219-1. $50.00, hardcover. Mantauran is one of the six dialects of the Formosan language Rukai, spoken in the south-central region of Taiwan. It is spoken by only 250–300 people and is highly endangered, with only a few elderly speakers still fluent. This alone is reason enough to document the language that in a generation or so will probably no longer be spoken. Rukai is unique in that it apparently exhibits an accusative case-marking system, while most other Formosan languages are arguably ergative, and it does not exhibit the widespread “focus” system characteristic of the so-called “Philippine-type” languages of Taiwan, such as Amis, Kavalan, Bunun, Thao, and Atayal. While a substantial grammar exists of one of the other dialects, Tanan Rukai (Li 1973), until Elizabeth Zeitoun (henceforth EZ) began her research on the language, there was very little information available about the morpho-syntax of this dialect. With this grammar, we now have extensive coverage of two considerably different dialects of Rukai. EZ's goals in writing the grammar in effect match the reasons given above. They were “to provide a description of the most salient characteristics of the grammar of Mantauran in order to reach a better understanding of this language and second, to make available enough empirical data to show in what respect Mantauran differs from the other Rukai dialects and other Formosan languages in general” (13). In these respects it is clear that EZ has succeeded admirably. The grammar is a model of clear prose and elegant argumentation supported by a multitude of carefully chosen examples drawn primarily from over 600 pages of transcribed narrative and folktale texts that the author collected from her primary language consultant. Chapter 1 discusses the current status of Mantauran Rukai (henceforth MR), providing brief notes on some of the commonly used loanwords, most introduced during the Japanese colonial period, and it is to this language, according to the author, that speakers persistently resort. The possibility that Japanese has also influenced the morphology will be commented on below. This chapter also provides the theoretical orientation of the work, stating that the grammar is a functional and empirically based account of MR, utilizing principles laid out by Dixon (1997) and Noonan (2006). The Conclusion (463) also notes that the grammar is “not circumscribed in any formal theory.” Nevertheless, various syntactic operations used by formalists, such as “raising,” form part of her argumentation to support one analysis over another in later chapters. A succinct outline of the grammar closes the chapter. Chapter 2 provides a standard structuralist account of the phonology and morphophonemics of MR, and a summary of the sound changes that have occurred in the language from Proto-Rukai as reconstructed by Li (1977). Of particular interest in this chapter is the evidence, rare in Austronesian languages, of a contrast between vowel-initial forms, and glottal stop-initial forms, such as ʔoɭipotso ‘unwrap’ vs. oɭipotso ‘wrap’. Of interest in the morphophonemics section are the various processes labeled by EZ as rightward [End Page 294] and leftward “glottal hopping” associated with the addition of various affixes. Typically, for much of the grammar, EZ provides a clear summary of the data, drawing generalizations and providing explanations where possible, and acknowledging problems that she is unable to account for. Chapter 3, Morphological units and morphological processes, begins as do most chapters with definitional statements and supporting general literature. EZ briefly outlines various approaches to the description of words, including IA and IP morpheme-based accounts, generative lexeme-based morphology, word and paradigm, and seamless morphology, and makes explicit her claim that, despite recognized difficulties with morpheme-based accounts, this model allows a transparent treatment of the structure of MR words, helps account for the distribution of some forms, and facilitates a comparison with other Rukai dialects and other Formosan languages (45). She concludes that typologically MR is a synthetic-agglutinative language, with a wide range of “dependent” morphemes, or...

Portuguese converted deverbal nouns: Constraints on their bases

The aim of this paper is to analyse the constraints that govern the formation of Portuguese converted deverbal nouns (‘CDNs’). To this end, we have analysed a total of 1323 converted deverbal nouns. The first type of constraints investigated are those found at the prosodic level: these deal with the configurational formatting of the minimal root. We will focus on the relationship between these constraints and the semantic and phonological identification of the lexical item in perceptual terms. The second level of constraints may be characterised as morphophonological-pragmatic. Many verbs contain morphological units that block the formation of CDNs because their [+Latinate] character has a certain stylistic effect in terms of pragmatic usage. The third level of constraints pertains to lexical-conceptual structure combined with argument structure.We will show that (i) the constraints on the bases of CDNs are not exclusively founded on morphological incompatibilities between derivational affixes and other morphological units with which they join. Thus, a derivational mechanism that does not involve affixation, such as conversion, is also ruled by restrictions on the bases. (ii) Structural constraints – based on argument structures and on prosodic, morphological and lexical-semantic structures – are interwoven with processing and pragmatic conditions. (iii) Word formation is organised in structures that have interfaces with each other.

Morphological effects of different channel‐forming discharges in a gravel‐bed river

AbstractThe study analyses the morphological response of a gravel‐bed river to discharges of different magnitude (from moderate events that occur several times a year to a 12‐year flood) and so defines the range of formative discharges for single morphological units (channels, bars, islands) and a range of magnitude of morphological activity from the threshold discharges for gravel transport and minor bar modification up to flows causing major morphological changes.The study was conducted on the Tagliamento River, a large gravel‐bed river in north‐eastern Italy, using two different methods, analysis of aerial photographs and field observation of painted gravel particles. The available photographs (five flights from August 1997 to November 2002) and the two commissioned flights (June 2006 and April 2007) do not define periods with a single flood event, but the intervals are short enough (11 to 22 months) to have a limited number of flood events in each case. The fieldwork, which involved cross‐section survey, grain‐size analysis and observation of painted sediments, complemented the aerial surveys by allowing analysis of channel response to single flood events.Substantial morphological changes (e.g. bank erosion of several tens of metres up to more than 100 m) associated with flood events with a recurrence interval between 1·1 year and 12 years have been documented. Multiple forming discharges were defined based on the activity of different morphological units. Discharges equal to 20–50% of the bankfull discharge are formative for the channels, whereas the bankfull discharge (1·1 year flood in this case of the Tagliamento River) is formative for low bars. Larger floods, but still relatively frequent (with a recurrence interval less than five years), are required for full gravel transport on high bars and significant morphological changes of islands. Copyright © 2009 John Wiley &amp; Sons, Ltd.

Emergent feature structures: harmony systems in exemplar models of phonology

In exemplar models of phonology, phonotactic constraints are modeled as emergent from patterns of high activation between units that co-occur with statistical regularity, or as patterns of low activation or inhibition between units that co-occur less frequently or not at all. Exemplar models posit no a priori formal or representational properties to the phonological units or sound patterns that emerge from the statistical regularities of speech, in contrast to analyses in the generative phonology tradition, including Optimality Theory, where sound patterns are determined by well-formedness constraints on phonological structures. This paper focuses on the analysis of long-distance assimilation, i.e., harmony systems, evaluating the predictions of generative analyses based on constraints on representation against typological and experimental evidence. Representational approaches model assimilation with constraints that favor extended feature structures. The question addressed here is whether and how the feature structures of harmony systems can be modeled as emergent structure. It is shown that an exemplar account can model the co-occurrence patterns of harmony systems in the transitional probabilities between segments that share the harmony feature, without invoking feature structure, but that the domain properties of harmony feature structures emerge due to the associations between phonological units (the harmonizing segments) and the morphological units that delimit harmony domains. This association grounds the sound pattern in the lexicon, and provides a “convergence of regularities” [Frisch, S., 2007. Levels of representation in acquisition (Commentary). In: Cole, J., Hualde, J.I. (Eds.), Laboratory Phonology, vol. 9. Mounton de Gruyter, Berlin, pp. 339–352] which facilitates learning.

Artificial steps to stabilize mountain rivers: a post‐project ecological assessment

AbstractThis paper compares the ecological response of reaches treated with traditional (check dams, CDs) and morphologically based (artificial steps, ASs) grade‐control works installed in a mountain river, where an unmodified reach provided reference conditions. Coarse particulate organic matter (CPOM) retentiveness was measured at the reach scale using artificial leaf release experiments. Macroinvertebrate sampling was carried out by a Surber net at pool‐ and run‐type morphological units within the three reach types, and hydraulic and sediment characteristics were measured at each Surber sampling site. In addition to calculating a variety of parameters to describe hydrodynamic and macroinvertebrate characteristics within reaches and morphological units, biotic (Extended Biotic Index, IBE) and ecological (Fluvial Functionality Index, IFF) index scores were also calculated. Results averaged at the reach scale show that CPOM retention, macrobenthos taxa richness and diversity were higher in the presence of a natural bed morphology, whereas both types of grade‐control works alter CPOM dynamics and macroinvertebrate communities. However, ASs showed CPOM retention dynamics and macroinvertebrate richness and diversity that were closer to the unmodified reach than CDs. Analysis at the unit scale demonstrated strong links between hydraulic variables and macroinvertebrate parameters such as abundance, diversity and proportion of shredders (SHR). Overall, ASs seem to provide a good trade‐off between the need to limit channel incision whilst maintaining aquatic ecosystems. Copyright © 2009 John Wiley &amp; Sons, Ltd.

A unifying framework for shoreline migration: 1. Multiscale shoreline evolution on sedimentary coasts

A unifying framework for shoreline migration is presented which synthesizes problems from coastal engineering, geomorphology, and stratigraphy into a common quantitative basis. Consideration of characteristic problems from these fields reveals that multiscale shoreline evolution problems naturally break into three classes on the basis of the morphologic unit of evolution: shoreface bed versus shoreline planform versus stratigraphic shoreline trajectory. Shoreline evolution models correspondingly break into morphodynamic, morphokinematic, and hybrid approaches. A generalized shoreline continuity equation is derived, the shoreline Exner equation, which subsumes equilibrium profile models commonly used in geomorphology and engineering and provides a natural framework for interpreting shoreline trajectories preserved in the sedimentary record. The shoreline Exner equation provides a rigorous basis for geometric and moving boundary models, which have significant untapped potential for shoreline migration problems. Recent advances in computational methods for evolving interface problems make hybrid models particularly attractive for problems of large‐scale planform shoreline dynamics, such as delta evolution.

Helical virus particles formed from morphological subunits of a membrane containing icosahedral virus

The classic publication by Caspar and Klug in 1962 [Physical principles in the construction of regular viruses. Cold Spring Harbor Symp. Quant. Biol. 27:1–24.] has formed the basis of much research on virus assembly. Caspar and Klug predicted that a single virus morphological unit could form a two dimensional lattice composed of 6-fold arrays (primitive plane), a family of icosahedra of increasing triangulation numbers ( T) and helical arrays of varying length. We have shown that icosahedral viruses of varying T numbers can be produced using Sindbis virus [Ferreira, D. F. et al. 2003. Morphological variants of Sindbis virus produced by a mutation in the capsid protein. Virology 307:54–66]. Other studies have shown that Sindbis glycoproteins can also form a 2-dimensional lattice confirming Caspar and Klug's prediction of the primitive plane as a biologically relevant structure [VonBonsdorff, C. H., and S. C. Harrison. 1978. Sindbis virus glycoproteins form a regular icosahedral surface lattice. J. Virol. 28:578]. In this study we have used mutations in the glycoproteins of membrane containing Sindbis virus to create helical-virus-like particles from the morphological subunits of a virus of icosahedral geometry. The resulting virus particles were examined for subunit organization and were determined to be constructed of only 6-fold rotational arrays of the virus glycoproteins. A model of the tubular virus particles created from the 6-fold rotational arrays of Sindbis virus confirmed the observed structure. These experiments show that a common morphological unit (the Sindbis E1–E2 heterodimer) can produce three different morphological entities of varying dimensions in a membrane-containing virus system.

Physical properties of morphological units on Comet 9P/Tempel 1 derived from near-IR Deep Impact spectra

In this paper we analyze near-infrared thermal emission spectra of the spatially resolved nucleus of Comet 9P/Tempel 1 obtained by the NASA spacecraft Deep Impact. Maps of spectral reddening, the product X ′ between the beaming function and directional emissivity, as well as surface temperature are constructed. Thermophysical modeling is used to estimate the degree of small scale surface roughness and thermal inertia by detailed reproduction of the empirical temperature map. Mie and Hapke theories are used in combination with numerically calculated beaming functions to analyze the X ′ map and place constraints on composition and grain size of the surface material. We show that it is absolutely mandatory to include small scale surface roughness in thermophysical modeling of this object, since the resulting self heating is vital for reproducing the measured temperatures. A small scale self heating parameter in the range 0.6 ⩽ ξ ⩽ 0.75 is common, but smoother areas where 0.2 ⩽ ξ ⩽ 0.3 are also found. Contrary to models neglecting small scale surface roughness, we find that the thermal inertia of Comet 9P/Tempel 1 generally is high (1000–3000 J m −2 K −1 s −1/2), although it may be substantially lower (40–380 J m −2 K −1 s −1/2) in specific areas. We obtain a disk-averaged reddening of 3.5% kÅ −1, with statistically significant local variations around that value on a ± 1.0 % kÅ − 1 level. Vast regions appear covered by small (∼0.1 μm) highly absorbing grains such as carbon or iron-rich silicates. Other regions appear dominated by somewhat larger (∼0.5 μm) and/or less absorbing grains such as troilite or magnesium-rich silicates. Surface variations in reddening, roughness, thermal inertia, composition and/or grain size are moderately to strongly correlated to the locations of morphological units on the surface. The existence of morphological units with differing physical properties may be primordial, hence reflecting a diversity in the building block cometesimals, or resulting from evolutionary processes.

Estimating spatial and temporal patterns of urban anthropogenic heat fluxes for UK cities: the case of Manchester

A model is proposed for determining the temporal and spatial patterns of anthropogenic heat fluxes in UK urban areas. It considers buildings, traffic, and metabolic heat flux sources and has been evaluated to a good accuracy against alternative data for the Greater Manchester area in the UK. Results are presented at spatial resolution of 200 × 200 m although the model itself is scalable depending on data availability. In this paper, results are generated using a set of urban morphology units so that detailed and time-consuming accounting of individual building and road emissions is not required. The model estimates a mean heat emission of 6.12 Wm-2 across Greater Manchester, with values in the region of 10 Wm-2 for non central urbanized areas and 23 Wm-2 in city center areas. Despite this difference, the results are not described by a simple distance decay function, as has been reported for other cities, due to the influence of satellite towns and the influence of the road network. Buildings are the dominant emitter, contributing some 60% of total emissions across the city compared to around 32% for road traffic and 8% for metabolic sources.

Viticultural terroirs in Stellenbosch, South Africa. I. The identification of natural terroir units

&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Aims&lt;/strong&gt;: A natural terroir unit (NTU) can be defined as a unit of land that is characterized by relatively homogenous topography, climate, geological substrate and soil. The mapping of NTUs is the first stage of data acquisition in a terroir study. This study aimed to identify NTUs using a Geographic Information System and to characterize the Stellenbosch Wine of Origin District using existing digital information at the scale of a wine producing district.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Methods and results&lt;/strong&gt;: The study area is bordered by mountains, situated close to the Atlantic Ocean and bisected by the Eerste river valley, resulting in notable spatial variation of all climatic parameters. The geology is complex due to the high degree of tectonic movement and mixing of parent material. Terrain morphological units, altitude, aspect and soil type were used as primary keys/variables for the identification of NTUs. Each of the identified units was further described with respect to the extent of the expected sea breeze effect and, for certain of the soil types, the associated parent material. A total of 1389 NTUs were identified in the Stellenbosch Wine of Origin District.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Conclusions&lt;/strong&gt;: Many of the natural terroir units identified for the Stellenbosch Wine of Origin District are of a size that is not economically or practically viable.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Significance and impact of the study&lt;/strong&gt;: The natural terroir units should be grouped into larger, more manageable and thus more viable terroir units using data relating their viticultural and oenological potential. This task will be addressed in subsequent companion papers.&lt;/p&gt;

Motor unit potential morphology differences in individuals with non-specific arm pain and lateral epicondylitis

BackgroundThe pathophysiology of non-specific arm pain (NSAP) is unclear and the diagnosis is made by excluding other specific upper limb pathologies, such as lateral epicondylitis or cervical radiculopathy. The purpose of this study was to determine: (i) if the quantitative parameters related to motor unit potential morphology and/or motor unit firing patterns derived from electromyographic (EMG) signals detected from an affected muscle of patients with NSAP are different from those detected in the same muscle of individuals with lateral epicondylitis (LE) and/or control subjects and (ii) if the quantitative EMG parameters suggest that the underlying pathophysiology in NSAP is either myopathic or neuropathic in nature.MethodsSixteen subjects with NSAP, 11 subjects with LE, eight subjects deemed to be at-risk for developing a repetitive strain injury, and 37 control subjects participated. A quantitative electromyography evaluation was completed using decomposition-based quantitative electromyography (DQEMG). Needle- and surface-detected EMG signals were collected during low-level isometric contractions of the extensor carpi radialis brevis (ECRB) muscle. DQEMG was used to extract needle-detected motor unit potential trains (MUPTs), and needle-detected motor unit potential (MUP) and surface detected motor unit potential (SMUP) morphology and motor unit (MU) firing rates were compared among the four groups using one-way analysis of variance (ANOVA). Post hoc analyses were performed using Tukey's pairwise comparisons.ResultsSignificant group differences were found for all MUP variables and for MU firing rate (p < 0.006). The post-hoc analyses revealed that patients with NSAP had smaller MUP amplitude and SMUP amplitude and area compared to the control and LE groups (p < 0.006). MUP duration and AAR values were significantly larger in the NSAP, LE and at-risk groups compared to the control group (p < 0.006); while MUP amplitude, duration and AAR values were smaller in the NSAP compared to the LE group. SMUP duration was significantly shorter in the NSAP group compared to the control group (p < 0.006). NSAP, LE and at-risk subjects had lower mean MU firing rates than the control subjects (p < 0.006).ConclusionThe size-related parameters suggest that the NSAP group had significantly smaller MUPs and SMUPs than the control and LE subjects. Smaller MUPs and SMUPs may be indicative of muscle fiber atrophy and/or loss. A prospective study is needed to confirm any causal relationship between smaller MUPs and SMUPs and NSAP as found in this work.