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The present study analysed the condition factor (K) and the hepato-somatic index (I H ) of the Brazilian sharpnose shark Rhizoprionodon lalandii during its entire life cycle. Discontinuity of liver growth was observed after sexual maturity. High condition values were recorded in the length classes of 300-350 mm (neonates), when the livers represented about 8% of total mass, decreasing until the length classes of 400-450 and 450-500 mm in females and males, respectively. Seasonal analysis exhibited low I H values in the summer, while for K, low values were in spring, indicating greater investment for body growth during spring and for gonad maturation in summer. Such findings indicate that this small coastal shark species accumulates reserve substances in the liver that will be used during reproduction. The decline in I H values in juveniles suggests that reserves provisioned by the mother to the neonate liver can be used in the first months of life.

The entire life cycle of influenza virus involves viral attachment, entry, replication, and release. Previous studies have demonstrated that neuraminidase (NA) is an essential glycoprotein on the surface of influenza virus and that it is responsible for release of progeny virions from the host cell to infect new cells. However, recent studies have also suggested that NA may play other roles in the early stages of the viral life cycle, that is, viral attachment and entry. This review focuses on the new role of NA in the early stages of influenza life cycle and the corresponding development of novel NA inhibitors. Copyright © 2016 John Wiley & Sons, Ltd.

There are many substances that can interfere with olive oil quality. Some of them are well characterized, but many others have an unknown origin. Saturated hydrocarbons make an extraordinary complex family of numerous molecules, some of them present naturally in vegetable oils. When major natural saturated hydrocarbons are analyzed by standard chromatographic methods, this complex mixture of saturated hydrocarbons appears as a hump in the chromatogram and is commonly named as unresolved complex mixture (UCM), whose origin remains unknown.; Results: In this work we studied the occurrence and the origin of aliphatic saturated hydrocarbons in olive oil. Hydrocarbons were analyzed in olive oil and along the industrial process of oil extraction. We also analyzed n-alkanes and the UCM fraction of hydrocarbons in leaf, fruit and oil from different varieties and different locations, and we also analyzed the soils at these locations.; Conclusions: We conclude that the hydrocarbons present in olive oil do not necessarily have their origin in a contamination during olive oil elaboration; they seem to have a natural origin, as a result of olive tree metabolism and/or as the result of an intake and accumulation by the olive tree directly from the environment during its entire life cycle. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

Improving design methods for affordability has become a necessity in the DOD. The concept of affordability can seem straightforward. The difficulty arises when an attempt is made to specify and quantify the affordability of a system. This is significant when writing a specification or when comparing two affordable solutions to conduct an affordability trade study or award a contract based on affordability. This paper examines affordability, its contextual dependence and suggests a method for specifying affordability. We start from a Department of Defense (DoD) perspective because of the large amount of effort expended by DoD and its support contractors in trying to resolve these problems. All of the DoD affordability activities performed during system development have direct analogues in non-DoD environments. The foundation for this paper is the DoD and commercial definitions of affordability, as well as, the Dr. Ashton Carter's, Undersecretary of Defense for Acquisition, Technology, and Logistics (ATL), affordability directives which formed the basis for the DoD thrust into this area. Using this as a basis, it is shown that: 1) affordability is dependent on the context in which it is evaluated with a distinction being made between Program and System affordability; and 2) affordability must be evaluated over the entire life cycle of the System of Interest (i.e., both the Primary System and the Enabling System). From this foundation a method of specifying affordability is derived and a specification resulting from this method is shown to: 1) support affordability comparisons between two systems; and 2) fit affordability trades into the standard trade study framework. Thus, it is demonstrated that affordability is not just an abstract concept but has real applicability in the development and life of systems and must be incorporated into Systems Engineering.

Extensive individual variation in spatial behaviour is a common feature among species that exhibit migratory life cycles. Nowhere is this more evident than in salmonid fishes; individual fish may complete their entire life cycle in freshwater streams, others may migrate variable distances at sea and yet others limit their migrations to larger rivers or lakes before returning to freshwater streams to spawn. This review presents evidence that individual variation in migratory behaviour and physiology in salmonid fishes is controlled by developmental thresholds and that part of the variation in proximal traits activating the development of alternative migratory tactics is genetically based. We summarize evidence that alternative migratory tactics co-exist within populations and that all individuals may potentially adopt any of the alternative phenotypes. Even though intra-specific genetic divergence of migratory tactics is uncommon, it may occur if female competition for oviposition sites results in spawning segregation of alternative phenotypes. Because of their polygenic nature, alternative migratory tactics are considered as threshold traits. Threshold traits have two characteristics: an underlying 'liability' trait that varies in a continuous fashion, and a threshold value which is responsible for the discreetness observed in phenotypic distribution. We review evidence demonstrating that body size is an adequate proxy for the liability trait controlling the decision to migrate, but that the same phenotypic outcome (anadromy or residency) may be reached by different developmental pathways. The evidence suggesting a significant heritable component in the development of alternative migratory tactics is subsequently reviewed, leading us to conclude that alternative migratory tactics have considerable potential to respond to selection and evolve. We review what is known about the proximal physiological mechanisms mediating the translation of the continuous value of the liability trait into a discontinuous migratory tactic. We conclude by identifying several avenues for future research, including testing the frequency-dependent selection hypothesis, establishing the relative importance of adaptive phenotypic plasticity in explaining some geographic gradients in migratory behaviour and identifying the physiological and genetic basis of the switching mechanisms responsible for alternative migratory tactics.

Bruckenbauwerke stellen einen unentbehrlichen Bestandteil der Infrastruktur dar und umfassen ein groses offentliches Investitionsvolumen. Im Vergleich zum Hochbau handelt es sich bei Brucken um besonders langlebige Bauwerke mit einer planmasigen Nutzungsdauer von 100 Jahren. Es ist daher ersichtlich, dass der Nachhaltigkeit im Bruckenbau ein besonderes Augenmerk geschenkt werden muss. In dem zum Titel des Artikels gleichnamigen Forschungsprojekt P843 wird eine ganzheitliche Bewertung von Stahl- und Verbundbrucken durch die Analyse der drei Aspekte der okologischen Qualitat, der okonomischen Qualitat und der sozialen und funktionalen Qualitat durchgefuhrt. Drei unterschiedliche Typen von Referenzbrucken werden in diesem Forschungsvorhaben uber den gesamten Lebenszyklus untersucht und bruckenbauspezifische Besonderheiten fur die Nachhaltigkeitsbewertung herausgestellt. Durch die Erfassung von Degradationsprozessen kann eine moglichst prazise Vorhersage des Lebenszyklus und somit der erforderlichen Unterhaltungsmasnahmen erfolgen. Die Erarbeitung einer ganzheitlichen Datenbasis fur den Bruckenbau soll hier Grundlagen zur Entscheidungsunterstutzung bei Planung und Ausschreibung von Brucken und ihrer Beurteilung nach Kriterien der Nachhaltigkeit geben. Holistic assessment of steel and composite bridges according to criteria of sustainability. Bridges are essential for the infrastructure network and cover a large investment volume. Compared to building construction bridges are especially long-living structures with a scheduled service-life of 100 years. Therefore, it is evident that special attention must be focussed on the sustainability in bridge construction. In the research project P843, named as this article, a holistic assessment of steel and composite bridges is made by the analysis of the three aspects of the environmental, economic and socio/cultural quality. Three different types of reference bridges are studied over the entire life cycle and specific characteristics of bridges pointed out regarding sustainability analyses. By the description of degradation processes the life cycle can be described and anticipated as accurate as possible and required maintenance measurements planed. The elaboration of a holistic database for bridges shall give support during design and at tender stage for an evaluation by criteria of sustainability.

The environmental impacts of coffee consumption inter alia depend on the preparation method used by consumers. Preparation methods such as filter drip, pod machines and fully automatic coffee machines are the most common ones in Germany: 62% of the consumers use a filter drip machine to brew their coffee, 23% use filter pad machines and 15% use espresso machines such as fully automatic coffee machines or capsule systems. The aim of the different studies presented in this paper was to identify the critical environmental issues along the life cycle of coffee and to compare the different preparation methods of coffee regarding their influence on the environmental impacts. Within the Product Carbon Footprint (PCF) Pilot Project Germany, the PCF of one cup of a special type of coffee was analysed on behalf of Tchibo GmbH (Uberseering, Hamburg, Germany). As the results show, the preparation by the consumer is one crucial part of the entire life cycle of coffee, making up a share of 30% of the overall emissions. Another hot spot is the cultivation of coffee beans with 55%. Concerning the use phase, research shows that environmental impacts vary significantly depending on the preparation method used by the consumer. Main drivers are differences in power consumption of the respective technologies. Furthermore, different packagings of the coffee play a decisive role. Comparing the analysed appliances and defined usage scenarios in this study, the French press and filter drip machine performed best, followed by the filter pad machine. In contrast, the environmental impacts of the analysed fully automatic coffee machine and the capsule machine were highest. The reason for this was the high power consumption, especially in the machines' sleep and standby mode. Additionally, capsule machines contribute to the environmental impacts because of the aluminium and/or plastic packaging of the capsules, automatic coffee machines because of their cleaning and rinsing programmes. The detailed results indicate a significant savings potential in the use phase. The impacts not only depend on the specific energy efficiency of the chosen appliance but also on the usage behaviour.

Twitter is a fast growing real-time social media tool. As Twitter evolves, more and more people are partaking in sharing what is happening around the world through various Twitter applications. Hashtag use has become a unique tagging convention to help associate Twitter messages with certain events or contexts. Prefixed by a # symbol with a keyword, a Twitter hashtag serves as a bottom-up user-proposed tagging convention. It also embodies user participation in the process of hashtag innovation, especially as it pertains to information organization tasks. Diffusion of innovation (DoI) is a theory that helps to explain the adoption process of an innovation by modeling its entire life cycle according to the aspects of communications and human information interactions. Hence, diffusion theory offers valuable insights into interface design that supports Twitter hashtag use and access. It also assists in evaluating hashtag life cycles and thus offering information required for decision-making, in regard to hashtag management.

Im Kontext einer nachhaltigen Entwicklung konnten in den letzten Jahren vor allem im Neubaubereich eine Reihe von Fortschritten erzielt werden. Besonders hervorzuheben ist die Weiterentwicklung von Technologien zur Nutzung regenerativer Energien und neuer Baustoffe mit besonders geringer Warmeleitfahigkeit. Parallel wurden Konzepte fur Niedrigheizenergie- bis hin zu Passiv- und sogar Plusenergiehauser entwickelt und umgesetzt. Diese Gebaudestandards weisen einen geringen Heizenergiebedarf auf und ermoglichen so erhebliche Energieeinsparungen wahrend der Gebaudenutzungsphase. Es stellt sich die Frage, ob sich durch die Verwendung von neuen Technologien und Baustoffen ein Teil des Gesamtprimarenergiebedarfs von der Nutzungs- in die Erstellungs- und Instandhaltungsphase verlagert. Fraglich ist dabei auch, welche Mehrinvestitionen den erwarteten Betriebskosteneinsparungen gegenuberstehen. Um dies zu untersuchen, wurden exemplarisch fur ein freistehendes Einfamilienhauses mehrere Ausfuhrungsvarianten geplant und eine Lebenszyklusanalyse mit dem Programmwerkzeug LEGEP durchgefuhrt. Auf dieser Grundlage konnen fur das exemplarische Einfamilienhaus Aussagen hinsichtlich des lebenszyklusubergreifenden Primarenergiebedarfs sowie der Kostenentwicklung getroffen werden. Die Ergebnisse haben jedoch keinen allgemeingultigen Charakter. Sie machen deutlich, dass im Sinne eines nachhaltigen Ressourceneinsatzes fur den Einzelfall nur eine ganzheitliche Betrachtung zielfuhrend ist. Analysis and comparison of energy standards based on a typical single-family house in terms of energy demand and costs over the entire life cycle. Over recent years significant progress has been made with regard to sustainable development, particularly for new buildings. Particularly noteworthy are the advancement of renewable energy technologies and new building materials with very low thermal conductivity. In parallel, solutions for lowenergy, passive and even surplus-energy homes were developed and implemented. These building standards are characterised by low heating energy consumption and therefore enable significant energy savings during the building utilisation phase. The question is whether the application of new technologies and building materials results in a partial shift of the total primary energy demand from the utilisation phase to the construction and maintenance phase. It is also questionable, however, what additional investments are required to achieve the savings in operating costs. In order to answer this question a number of different design and construction options for a free-standing single-family house were examined and subjected to a life cycle analysis using the LEGEP software tool. Based on this analysis a number of statements regarding the primary energy demand over the life cycle of the exexemplary single-family house and also for the cost trend can be made. However, the results are not universally applicable. They indicate that a holistic analysis is required for each individual case in order to achieve sustainable resource use.

Die Frage nach den Umweltwirkungen von Produkten gewinnt aufgrund der zunehmenden Forderung nach der Berucksichtigung des Nachhaltigkeitsgedankens im Bauwesen stetig an Bedeutung. Die Okobilanz ist eine Methode, um die okologischen Wirkungen eines technischen Systems – im Bauwesen kann das z. B. ein Bauprodukt, aber auch ein gesamtes Gebaude sein – entlang dessen gesamten Lebenszyklus darzustellen. Okobilanzen von Bauprodukten sind seit Jahren etabliert, wahrend Okobilanzen von Gebauden erst allmahlich Verbreitung finden. Insbesondere das Deutsche Gutesiegel Nachhaltiges Bauen fordert diese Entwicklung durch die Einbeziehung des gesamten Lebenszyklus in die Nachhaltigkeitsbewertung von Gebauden. Bauschaffende haben sich allerdings gerade der Herausforderung der okologischen Optimierung eines Bauwerks bereits bei dessen Planung zu stellen. Mit Hilfe von Kooperationen zwischen Okobilanz-Experten und Fachleuten der Planung und des Baubetriebs konnen geeignete Losungen fur diese Aufgabe entwickelt werden. Dieser Aufsatz stellt eine Ubersicht uber Grundsatze und Anwendungen von Okobilanzen im Bauwesen zusammen und zeigt einen Losungsansatz fur die Frage nach der planungsintegrierten okologischen Optimierung auf (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Life cycle assessment in the construction sector. Under the impression of an increasing demand for sustainability thinking in the building and construction sector, the method of Life Cycle Assessment (LCA) is constantly gaining relevance. LCA is a method to quantify and assess the environmental impacts of technical systems – in the building and construction sector, these could be both, building products or complete buildings – over their entire life cycle. In the construction sector, LCAs of building products have been well established, while LCAs of entire buildings are just now becoming more common. The German certificate for sustainable buildings strongly promotes this development by including Life Cycle Thinking into the rating of the sustainability of buildings. Due to this development, planners and other stakeholders in the construction industry have to face the necessity of life cycle based environmental optimization of a building already during the planning phase of the building. With the cooperation of LCA experts and experts in the field of assistance in the planning and construction process, dedicated and feasible solutions for this task can be developed. This article provides an overview on LCA in the building and construction sector and presents a possible approach to the question of planning-integrated environmental optimization of buildings.

In recent years, legislatures across the world have turned their attention to the escalating amount of electronic and electrical waste, and their accompanying environmental threats. Increasing consumption of electronic and electrical equipment (EEE) and the indiscriminate disposal of used products contribute to the problem furthered by designs that ignore durability and support the limitless use of toxic substances. One proposed method of changing this trend is to stimulate producers to design for the environment (DFE). In many ways DFE breaks the traditional physical barriers for design and requires a vision of the product for its entire life cycle. As Canada's provincial and federal governments move to respond to the problem of e-waste, their chosen approaches are critically analysed. In particular, this article investigates how the provinces of Alberta, Saskatchewan, British Columbia, Nova Scotia and Ontario conceptualize the problem of e-waste. In addition, the extent to which the policy goals and financing mechanisms incorporated in each programme adequately consider the role of DFE is evaluated.

A new method for analyzing life cycle cost risk on large programs is presented that responds to an increased emphasis on improving sustainability for long-term programs. This method provides better long-term risk assessment and risk management techniques. It combines standard Monte Carlo analysis of risk drivers and a new data-driven method developed by the Hoy and Hudak (1994). The approach permits quantification of risks throughout the entire life cycle without resorting to difficult to support subjective methods. The Hoy-Hudak methodology is shown to be relatively straightforward to apply to a specific component or process within a project using standard technical risk assessment methods. The total impact on system is obtained using the program WBS, which allows for the capture of correlated risks shared by multiple WBS items. Once the correlations and individual component risks are captured, a Monte Carlo simulation can be run using a modeling tool such as Analytica to produce the overall life cycle cost risk.

A NUMBER of ectoparasites can affect sheep in the UK, with potentially serious consequences. Production can be severely affected, in terms of reduced milk and meat yields, downgrading of wool and leather, and the need for expensive control programmes. Ectoparasitic infestations also significantly compromise the welfare of flocks and individual sheep, and may result in prosecutions for animal cruelty. Effective control depends on whether the ectoparasite is permanent (ie, spends its entire life cycle on sheep) or semipermanent (ie, has at least one free-living stage). This article describes the various classes of ectoparasiticides and how they may be applied to animals for best effect. In view of concerns over resistance and pesticide safety, which may have implications for future product availability, it also outlines some alternative methods of control which might be implemented instead of, or in combination with, traditional ectoparasiticides.

Optimal defense theory (ODT) predicts that plants should have the highest defense levels in parts that have the highest value in terms of fitness. Assumptions about differences in fitness value among plant parts have previously been based on general reasoning, e.g., that reproductive tissue is more valuable than vegetative tissue since fitness ultimately depends on reproduction. Here we present a first example of how demographic elasticity (proportional sensitivity) analysis can be used as a tool to generate more objective and specific estimates of the fitness value of different plant parts, based on the entire life cycle. These estimates were further used to generate testable predictions about intraplant variation in defenses of the brown seaweed Ascophyllum nodosum (knotted wrack). The predictions were clearly supported by the results from both analyses of chemical defense levels (phlorotannins) and bioassays (feeding preference experiments), which showed that reproductive tissues had the lowest defense level of the three examined tissue types, in contrast to previous assumptions. We suggest that a stronger focus on variation in life history among species and populations, with demographic perturbation analysis as one important tool, could lead to a better understanding of intraplant variation in defense levels, in seaweeds as well as vascular plants and other modular organisms.

This article gives a short description of recent progress accomplished in order to integrate logistics through the entire life cycle activities, the strategy implemented for maintaining efficient operational availability in our future ships, and the present areas of research concerning maintenance concepts.

Reproductive performance data were collected for inland fall chinook salmon Oncorhynchus tshawytscha from Lake Oahe, South Dakota, in 1988 and 1998. This population exists outside the native geographical range of chinook salmon and completes its entire life cycle in freshwater. Female weights and lengths, total fecundity, relative fecundity (eggs/mm), egg size, and egg survival were all considerably less than reported for anadromous chinook salmon stocks in their native range. Mean weight of spawning females was 2.73 kg in 1988 and 2.01 kg in 1998. Total fecundity was not significantly different at 2,892 eggs in 1988 and 2,496 eggs in 1998. Egg survival to the eyed stage averaged 37.7% in 1988 and 43.8% in 1998 and ranged from 0% to 96%. Relative fecundity (eggs/kg), egg size, and egg survival to the eyed stage were similar for each year. Relative fecundity (eggs/mm of total length) declined from 1988 to 1998. Total fecundity was linearly related to fish length in 1998 and in both years combined....

Improving the eco-efficiency of products is gaining increasing attention within industry. Through eco-efficiency, companies aim to reduce the environmental impact of their products throughout the entire life cycle, while at the same time creating promising market opportunities or reducing costs. This article describes how companies can integrate eco-efficiency aspects into the product development process. © 2000 John Wiley & Sons, Inc.

Growth temperature influences the seed yield of soybean [Glycinemax (L.) Merr.]. Most studies have concentrated on the effects of concomitant increases in day/night temperature during the entire life cycle of soybean. A better understanding of the influence of combinations of high day and night temperature imposed during different reproductive growth phases on soybean seed yield would be beneficial in identifying yield limiting factors. Day/night temperatures of 30/20, 30/30, 35/20, and 35/30°C were imposed during flowering and pod set (R1-R5), seed fill and maturation (R5-R8), and during the entire reproductive period (R1-R8). Increases in day temperature resulted in decreased seed formation when plants were exposed during flowering and pod set and decreased seed growth when exposed during flowering and pod set or seed fill. Seed growth reductions in plants exposed to the high day temperature were accompanied by decreased photosynthetic rates. The largest yield reduction in this study was 27% and occurred when 35°C occurred for 10 h per day from flowering to maturity. No significant losses in yield occurred at high night temperature at any reproductive growth phase. The only significant interaction between day and night temperature for the yield components was for seed weight per plant during flowering and pod set. Night temperature stress did not occur at 30°C and a night temperature of 20°C did not reduce the yield loss from daytime high temperature stress. This study suggests that soybean seed yield reductions from high temperatures are primarily a response to day temperature and moderate to high night temperatures have a small affect on soybean seed yield components. Contribution as Journal Paper No. J-16045 of the Iowa Agric. and Home Econ. Exp. Stn., Ames; Project No. 2775

Life-Cycle Assessment (LCA) is an analytical tool that evaluates the environmental consequences of a product, process, or activity across its entire life cycle. LCA is used internationally by government and industry to obtain a comprehensive perspective of the interactions between an activity and the environment and provides a method to systematically identify opportunities for improvement. The framework is integrated into environmental management programs motivated by market awareness, public perception, and cost savings. The use of LCA is driven by external forces such as eco-labels and the recent development of the ISO 14000 standards. However, LCA has many shortcomings that need to be addressed. The concerns of poor data quality, data availability, high implementation costs, subjectivity, and lack of standardization have sent LCA into a state of flux. In light of the recent surge of interest in LCA, the authors of this article have conducted a corporate survey that targets the implementation of LCA. Their goal is to determine the level of activity of LCA among known practitioners and to elucidate common themes. This article presents their findings from responses by 34 companies that were known to be actively involved in LCA or contemplating its future use.

Recent years have seen advancements in the development and use of life-cycle assessment (LCA) analytic techniques. Although these techniques have highlighted the power of LCA to identify the environmental consequences of a product system through its entire life cycle, they have also highlighted a major shortcoming of LCA—the lack of cost information. Because companies make daily decisions that involve trade-offs between economics and the environment, including cost information in LCA is critical for advancing its use as an overall environmental decision-making tool. This article outlines the current state of LCA methodology development, defines key life-cycle cost assessment terms and concepts, and evaluates existing cost assessment techniques with the objective of building an integrated life-cycle cost assessment tool.

This paper describes a project that is studying an expert system (ES) development method tailored to meet the requirements of small and medium-sized enterprises (SMEs). It is posited that many such organisations cannot use ES technology because of its high entry price and because the available tools and methods were developed for and by large organisations. Within this context our development method encompasses the entire life cycle of an ES from initial conception to implementation through to maintenance and updating. The central premise is that the method should be ‘client-centred’, emphasising what the client can see, rather than being ‘technology-centred’, emphasising how the knowledge engineers work. Discussion includes how this methodology addresses many criticisms of current ES development methods, including rapid prototyping and KADS.

The place of origin, sequence of appearance and the shape of various non-resinous secretions during the entire life cycle of both male and female lac insects, have been described here. Properties of the secretions found in the adult female are also given. A total of 20 non-resinous secretions has been found in Kerria lacca. Fourteen of these secretions–dorsal relic, pencils, brachial mass, large anal hairs, short anal hairs, brachial core, major spiracular secretion, minor spiracular secretion, non-stalked girdle fibres, stalked girdle fibres, thin ventral patch, oral lobe secretion, brachial marginal secretion and cavaera secretion–are present both in male and female lac insects. Three secretions– opercular secretion, canella secretion and caudal filaments–occur only in the male while the remaining three–ventrolateral compact flat fibres, ventrolateral long coiled threads and perivaginal fine filaments–occur only in the female. Two types of non-resinous secretions, 13 waxy and four non-waxy, occur in female K. lacca. The dorsal relic, pencils and their modifications (anal tubercular splint and anal tubercular shield), brachial mass, large anal hairs, short anal hairs, major spiracular secretion, minor spiracular secretion, non-stalked girdle fibres, thin ventral patch, oral lobe secretion, brachial marginal secretion, cavaera secretion and ventrolateral compact flat fibres are waxy in nature, whereas the brachial core, stalked girdle fibres, ventrolateral long coiled threads and perivaginal fine filaments are non-waxy.

Heavy losses of largemouth bass fingerlings at the Jonkershoek Inland Fish Hatchery, Stellenbosch, South Africa, were attributed to heavy infestation of the ureters with a gyrodactyloid parasite closely related to Acolpenteron ureterocoetes. The parasite has no intermediate host, and in heavily infested fish may complete its entire life cycle in the ureters. Infected fish display inflammation of the kidneys, ureters, and urinary openings and, in acute cases, great abdominal distension anterior to the cloaca. Some diseased fish die gradually, others in convulsive spasms. This disease occurs only in fish reared on artificial food in concrete rearing tanks. The spread of the disease can be checked by transferring fish from such small tanks to fertilized open ponds, where natural food and absence of crowding usually alleviate the condition. It is recommended that largemouth bass be reared to the fingerling stage in fertilized earthen ponds 0.1 acre or more in size, stocked at the rate of 12,000 advan...