Spatial variation in functional group diversity in a sandflat benthic community: implications for ecosystem resilience

The resilience of macrobenthic communities to environmental stress depends upon the vulnerability, adaptability and connectivity of species. Recent studies suggest that the function(s) species perform may be more influential in driving community response to change than the more traditional measures of abundance and occurrence. Species that perform similar functions within a community theoretically give rise to redundancy, an important attribute of resilience. This thesis assesses the potential for functional redundancy in coastal macrobenthic communities by comparing the degree of sharing of specific functional traits, patterns of abundance and spatial distribution to provide insight into the potential for resilience. The research is focused on the functional diversity of a species rich macrobenthic community from a large intertidal area in the Kaipara Harbour, New Zealand. 400 macrofaunal and 360 sediment cores were collected using a newly developed hierarchical sampling grid covering an area of 300,000 m². This resulted in a data set consisting of 115 taxa and 23,682 individuals and 360 observations of sediment grain size and chlorophyll a. Linking species attributes such as body type, size, feeding mode, and living depth, produced 26 species functional groups that characterised important functional attributes of the macrobenthic community. These attributes relate to ecosystem functions associated with sediment biogeochemistry, stability and resilience to disturbance. Redundancy was assessed within these functional groups (ranging from 1-13 species per functional group) considering both occurrence and abundance in their spatial distribution. Various levels of redundancy were identified for different functional groups, for example, functional groups characterised by small deposit-feeding polychaetes encompassed high redundancy, whilst functional groups consisting of large suspension-feeding, highly mobile bivalves maintained low redundancy. Nevertheless, the latter functional group does contribute considerably to abundance despite its low redundancy. The spatial patterns exhibited by different functional groups (identified by correlograms using Moran’s I) were used to provide insights to connectivity and exposure of the functional group to localised disturbance. A range of spatial patterns were apparent, reflecting small-scale homogeneity to large-scale heterogeneity with spatial arrangements including gradients and distinct patches. Density maps showed that some functional groups, such as tube worms and large mobile suspension-feeding bivalves, showed strong and opposing spatial distributions, separated by clear boundaries. Canonical correspondence analyses indicated that the measured environmental variables were not important drivers of the spatial distribution of functional groups. Thus, either biological interactions between functional groups are the driving force of spatial diversity or this sampling strategy failed to measure relevant environmental parameters. These findings emphasise a role for spatial variation in functional diversity and species redundancy in structuring community resilience. Understanding the functional roles of species, the diversity of these functions and associated biological interactions, is essential for evaluating biodiversity and resilience

The Canadian Position: Can Parties To An Arbitration Agreement Vary The Statutory Scope Of Judical Review Of The Award?

The U.S. Supreme Court issued its decision in Hall Street Associates, L.L.C. v. Mattel, Inc. on March 28, 200

The relations between the Slovaks and the central government of the First Czechoslovak Republic 1918-1938

This work is concerned with a study of the relations between the Slovaks and the Central Government of the First Czechoslovak Republic from 1918 to 1938 in most of the major areas of the major areas of social development. It is divided into nine chapters of which Chapter Five and Six form the core of the work and are devoted to an examination of the policies of this central government in Slovakia. Other chapters deal with the history of Slovakia and the reasons why that region was finally to become a constituent part of the Czechoslovak Republic, and there is also an attempt to examine the role of both individual Slovak politicians and Slovak parties in the political life of the Republic. Some attention is also devoted to the import in the events which proceeded the Munich crisis of 1938. Chapter Nine contains what I feel to the conclusions that can be drawn from the examination of the problems to which my study is devoted

Effects of Accelerated Carbonation Curing on CO2 Sequestration and on the Compressive Strength of Concrete Masonry Units

The global consumption of Portland cement has risen to over 4 billion tonnes per annum. Its manufacture is energy and carbon intensive and approximately 900 kg of CO2 is emitted into the atmosphere for each tonne of Portland cement produced. The International Energy Agency (IEA) roadmap sets out a goal to reduce emissions due to cement production to 18 % below 2006 levels by 2050. Concrete has the potential to re-absorb CO2 by the process of carbonation, where it reacts with CaO in the concrete to form calcium carbonate. Accelerated carbonation curing (ACC) is a technique for curing fresh concrete that can sequester CO2. ACC of concrete masonry units (CMU’s) can reduce the embodied carbon footprint and play a major role in sustainability by reducing global CO2. ACC also offers potential improvements in the mechanical and durability properties of concrete. Experimental work was carried out which involved the ACC of CMU’s at a CO2 concentration of 50% over various time intervals and exposure conditions. It was calculated that the maximum possible CO2 uptake potential of the cement was approximately 49.5%. A CO2 uptake of 23% per mass of cement was achieved after 7 days of ACC along with compressive strength increases of 15.4% and 28% for ACC samples at 7 and 28 days respectively. The study found that the greatest compressive strength increase occurred between 4 and 24 hours. After 24 hours the ACC process showed a similar proportional rate of strength gain over time when compared to the control. The study shows that ACC is different from weathering carbonation as it accelerates the hydration reaction of the unhydrated cement phases C3S and C2S producing rapid strength gains. Weathering carbonation occurs in concrete after the hydration process has been predominately completed and results in the decalcification of C-S-H and the formation of silica gel which is detrimental to the cement paste

Coexisting Angiomyolipoma and Renal Cell Carcinoma in a Kidney of an Elderly Woman: Case Report and Review of the Literature

Angiomyolipoma is a well described but relatively uncommon benign renal neoplasm composed of varying admixtures of mature adipose tissue, smooth muscle, and thick-walled blood vessels.[1] The incidence of angiomyolipoma is about 0.3% overall.[2] It frequently occurs in patients with tuberous sclerosis. Even more uncommon is the simultaneous occurrence of angiomyolipoma and renal cell cancer in the same kidney in a patient without tuberous sclerosis

Heterozygote Expression in Propionyl Coenzyme A Carboxylase Deficiency DIFFERENCES BETWEEN MAJOR COMPLEMENTATION GROUPS

A B S T R A C T We measured propionyl coenzyme A carboxylase (PCC) activity in extracts of skin fibroblasts and peripheral blood leukocytes from controls and obligate heterozygotes for PCC deficiency. 6 heterozygotes were from the pcc A complementation group; 12 were from the other major complementation group, designated pcc C. Mean PCC activity in fibroblast extracts from pcc A heterozygotes was 52% of that in controls, whereas mean PCC activity in pcc C heterozygotes was indistinguishable from that of controls. Similar results were obtained with extracts of peripheral blood leukocytes. In none of eight families (three pcc A and five pcc C) in which PCC activity was studied in both parents of an affected child were significant intrafamilial differences observed. The activities of two other mitochondrial enzymes (13-methylcrotonyl CoA carboxylase and glutamate dehydrogenase) were comparable in controls and both groups of heterozygotes. Whereas the data from pcc A heterozygotes are consistent with expected gene dosage effects, those from pcc C heterozygotes are not. Inasmuch as mammalian PCC is a large molecular weight tetramer, each protomer of which is probably composed of two nonidentical subunits, the latter results are most consistent with unbalanced rates of synthesis and(or) degradation of the two subunits in normal cells with compensatory balancing in pcc C heterozygotes

Next generation software environments : principles, problems, and research directions

The past decade has seen a burgeoning of research and development in software environments. Conferences have been devoted to the topic of practical environments, journal papers produced, and commercial systems sold. Given all the activity, one might expect a great deal of consensus on issues, approaches, and techniques. This is not the case, however. Indeed, the term "environment" is still used in a variety of conflicting ways. Nevertheless substantial progress has been made and we are at least nearing consensus on many critical issues.The purpose of this paper is to characterize environments, describe several important principles that have emerged in the last decade or so, note current open problems, and describe some approaches to these problems, with particular emphasis on the activities of one large-scale research program, the Arcadia project. Consideration is also given to two related topics: empirical evaluation and technology transition. That is, how can environments and their constituents be evaluated, and how can new developments be moved effectively into the production sector

Исследование коррозионных свойств биосовместимых покрытий на основе титана, осажденных методом реактивного магнетронного распыления

В работе изучались свойства Ti-O-N покрытий, нанесенных на стальные подложки методом реактивного магнетронного напыления, такие как коррозионная стойкость, термическая устойчивость, а так же диффузионные процессы в физиологических растворах. Методами инфракрасной спектроскопии и атомно-эмиссионного анализа была установлена химическая инертность пленки, а так же потенциальная биологическая активность в виду обнаружения оксида азота в модельных растворах после контакта с покрытиями Ti-O-N.The properties of Ti-O-N coatings deposited on steel substrates by the method of reactive magnetron sputtering, such as corrosion resistance, thermal stability, as well as diffusion processes in physiological solutions were studied. By the methods of infrared spectroscopy and atomic emission analysis, the chemical inertness of the film was established, as well as the potential biological activity in the form of detection of nitrogen oxide in model solutions after contact with Ti-O-N coatings

2012-2013 The Antique Club: Pictures at an Exhibition

https://spiral.lynn.edu/conservatory_otherseasonalconcerts/1015/thumbnail.jp