Life histories of some Australian Siphlonurid and Oligoneuriid mayflies (Insecta : Ephemeroptera)

1986 ◽  
Vol 37 (2) ◽  
pp. 261 ◽  
Author(s):  
IC Campbell

The life histories of nine populations of mayflies were investigated through monthly field collections over a 3-year period. Seven species were studied, one each from the genera Tasmanophlebia, Ameletoides and Mirawara (Siphlonuridae) and four from Coloburiscoides (Oligoneuriidae). Nymphs were sorted and measured and life histories inferred from size frequency diagrams, and cohorts were separated using a technique for distinguishing multiple overlapping normal distributions. The life histories were all relatively poorly synchronized with adult emergence extended over 5 months or more in every case. A wide size range of nymphs was present in most populations for most of the year and these often formed multiple overlapping cohorts. The time required for development by different cohorts of a single population was quite varied. Marked differences in the length and timing of the adult emergence period, and of the importance of particular cohorts, were apparent in different years. It was concluded that more than a single year's data from one site was necessary to interpret the life histories of Australian mayflies adequately. The four Coloburiscoides species investigated displayed a wide range of development times and patterns, the shortest being displayed by C. haleuticus. This species had some cohorts that seemed to complete their development in about 6 months, whereas C. giganteus had some cohorts that required up to 3 years and also appeared to have a nymphal or early-instar diapause of between 9 and 11 months. The life-history patterns found in this study did not readily fit into the classification schemes proposed by Northern Hemisphere workers. The general asynchrony found in this and previous Australian studies makes it doubtful that a useful classificatory system for Australian mayfly life histories can be developed.

1976 ◽  
Vol 108 (12) ◽  
pp. 1303-1318 ◽  
Author(s):  
Vincent H. Resh

AbstractBionomics of the stream caddisflies, Ceraclea transversa (Hagen) (= Athripsodes angustus Banks) and Ceraclea ancylus (Vorhies) (= Athripsodes ancylus (Vorhies)) were compared with generalized trichopteran life cycles. The univoltine detritus-feeding C. ancylus has five larval instars and a brief adult emergence period. C. transversa has five larval instars but two distinct cohorts, in which larvae of the first cohort feed entirely on freshwater sponge, overwinter as inactive prepupae, pupate, and emerge the following spring. The second larval cohort feeds on sponge until the onset of gemmulation in autumn, then the larvae must overwinter as active third- or fourth-instar detritus-feeders, pupating and emerging later in the summer than the first cohort. The detritus-feeding C. ancylus larvae have a diurnal feeding cycle. The sand case of C. ancylus and the silk-secreted case of C. transversa differ in shape and composition, although both species initiate case construction using egg mass matrix, silk, and detritus. Emergence, flight activity, sex ratios, and adult survival depart from reported generalizations of caddisfly biology. Neither the validity of generalizing typical life cycles in benthic studies, nor the rationale that congeneric species operate as a functional unit in stream dynamics, is substantiated.


1993 ◽  
Vol 44 (2) ◽  
pp. 363 ◽  
Author(s):  
RM St.Clair

Life history studies were carried out for populations of six species of Leptoceridae. Study sites were a permanent river (Acheron), a temporary river (Lerderderg) and a permanent lake (Monash University). Life histories varied in degree of synchrony of larval development, in length of adult emergence period, and from bi- to semivoltine. Oviposition requirements of adults were found to be the major factor influencing synchrony of the life history of one species. Life history features did not ameliorate the effects of the severe drought of 1982-83, nor did drought result in large changes in life histories.


Author(s):  
Anthony S-Y Leong ◽  
David W Gove

Microwaves (MW) are electromagnetic waves which are commonly generated at a frequency of 2.45 GHz. When dipolar molecules such as water, the polar side chains of proteins and other molecules with an uneven distribution of electrical charge are exposed to such non-ionizing radiation, they oscillate through 180° at a rate of 2,450 million cycles/s. This rapid kinetic movement results in accelerated chemical reactions and produces instantaneous heat. MWs have recently been applied to a wide range of procedures for light microscopy. MWs generated by domestic ovens have been used as a primary method of tissue fixation, it has been applied to the various stages of tissue processing as well as to a wide variety of staining procedures. This use of MWs has not only resulted in drastic reductions in the time required for tissue fixation, processing and staining, but have also produced better cytologic images in cryostat sections, and more importantly, have resulted in better preservation of cellular antigens.


Author(s):  
Trần Thanh Nhàn

In order to observe the end of primary consolidation (EOP) of cohesive soils with and without subjecting to cyclic loading, reconstituted specimens of clayey soils at various Atterberg’s limits were used for oedometer test at different loading increments and undrained cyclic shear test followed by drainage with various cyclic shear directions and a wide range of shear strain amplitudes. The pore water pressure and settlement of the soils were measured with time and the time to EOP was then determined by different methods. It is shown from observed results that the time to EOP determined by 3-t method agrees well with the time required for full dissipation of the pore water pressure and being considerably larger than those determined by Log Time method. These observations were then further evaluated in connection with effects of the Atterberg’s limit and the cyclic loading history.


2014 ◽  
Vol 660 ◽  
pp. 971-975 ◽  
Author(s):  
Mohd Norzaim bin Che Ani ◽  
Siti Aisyah Binti Abdul Hamid

Time study is the process of observation which concerned with the determination of the amount of time required to perform a unit of work involves of internal, external and machine time elements. Originally, time study was first starting to be used in Europe since 1760s in manufacturing fields. It is the flexible technique in lean manufacturing and suitable for a wide range of situations. Time study approach that enable of reducing or minimizing ‘non-value added activities’ in the process cycle time which contribute to bottleneck time. The impact on improving process cycle time for organization that it was increasing the productivity and reduce cost. This project paper focusing on time study at selected processes with bottleneck time and identify the possible root cause which was contribute to high time required to perform a unit of work.


2020 ◽  
Vol 41 (S1) ◽  
pp. s69-s70
Author(s):  
Angie Dains ◽  
Michael Edmond ◽  
Daniel Diekema ◽  
Stephanie Holley ◽  
Oluchi Abosi ◽  
...  

Background: Including infection preventionists (IPs) in hospital design, construction, and renovation projects is important. According to the Joint Commission, “Infection control oversights during building design or renovations commonly result in regulatory problems, millions lost and even patient deaths.” We evaluated the number of active major construction projects at our 800-bed hospital with 6.0 IP FTEs and the IP time required for oversight. Methods: We reviewed construction records from October 2018 through October 2019. We classified projects as active if any construction occurred during the study period. We describe the types of projects: inpatient, outpatient, non–patient care, and the potential impact to patient health through infection control risk assessments (ICRA). ICRAs were classified as class I (non–patient-care area and minimal construction activity), class II (patients are not likely to be in the area and work is small scale), class III (patient care area and work requires demolition that generates dust), and class IV (any area requiring environmental precautions). We calculated the time spent visiting construction sites and in design meetings. Results: During October 2018–October 2019, there were 51 active construction projects with an average of 15 active sites per week. These sites included a wide range of projects from a new bone marrow transplant unit, labor and delivery expansion and renovation, space conversion to an inpatient unit to a project for multiple air handler replacements. All 51 projects were classified as class III or class IV. We visited, on average, 4 construction sites each week for 30 minutes per site, leaving 11 sites unobserved due to time constraints. We spent an average of 120 minutes weekly, but 450 minutes would have been required to observe all 15 sites. Yearly, the required hours to observe these active construction sites once weekly would be 390 hours. In addition to the observational hours, 124 hours were spent in design meetings alone, not considering the preparation time and follow-up required for these meetings. Conclusions: In a large academic medical center, IPs had time available to visit only a quarter of active projects on an ongoing basis. Increasing dedicated IP time in construction projects is essential to mitigating infection control risks in large hospitals.Funding: NoneDisclosures: None


Author(s):  
Pavel Beracko ◽  
Andrea Kušnírová ◽  
Michaela Partlová ◽  
Jana Ciceková

<p>Our study examines community structure and nymphal biology (life cycles and secondary production) of stoneflies in two adjacent mountain streams with different degree of forest cover in the Prosiečanka River Basin (Chočské Vrchy Mts., West Carpathians). One of the streams has non-forested catchment, converted to meadows and pastures, while the other one has catchment with 60% covered by spruce forest. Differences in forest cover and in thermal regime of the streams were reflected by the difference of stonefly communities at their structural and functional level. Species <em>Nemoura cinerea and Leuctra aurita </em>created stonefly assemblage in non-forested stream, whereas <em>Nemoura cinerea</em> also occurred in naturally forested stream together with species <em>Leuctra armata, Leuctra nigra, Leuctra prima, Siphonoperla neglecta</em> and <em>Arcynopteryx dichroa</em>. All examined species had maximally annual life cycle and in eudominant species <em>Nemoura cinerea</em> one month shift was found in nymphal hatching and adult emergence between streams. Total secondary production of stoneflies in undisturbed stream (126.46 mg DW m<sup>-2</sup> y<sup>-1</sup>) was more than two times higher than the production in non-forested stream (47.39 mg DW m<sup>-2</sup> y<sup>-1</sup>). </p>


2009 ◽  
Vol 5 (5) ◽  
pp. 625-627 ◽  
Author(s):  
Paul Schmid-Hempel

To Darwin, parasites were fascinating examples of adaptation but their significance as selective factors for a wide range of phenomena has only been studied in depth over the last few decades. This work has had its roots in behavioural/evolutionary ecology on the one hand, and in population biology/ecology on the other, thus shaping a new comprehensive field of ‘evolutionary parasitology’. Taking parasites into account has been a success story and has shed new light on several old questions such as sexual selection, the evolution of sex and recombination, changes in behaviour, adaptive life histories, and so forth. In the process, the topic of ecological immunology has emerged, which analyses immune defences in a framework of costs and benefits. Throughout, a recurrent theme is how to appropriately integrate the underlying mechanisms as evolved boundary conditions into a framework of studying the adaptive value of traits. On the conceptual side, major questions remain and await further study.


2018 ◽  
Vol 30 (1) ◽  
pp. 16-24 ◽  
Author(s):  
Ian Towle ◽  
Eleanor R. Dove ◽  
Joel D. Irish ◽  
Isabelle De Groote

Enamel defects can provide insight into the life histories of past individuals and populations, in-cluding information on a wide range of disturbances during childhood. This study investigates a particularly severe case of plane-form enamel hypoplasia from a Roman site in Gloucester, UK. Dentine protrudes above the occlusal enamel of upper central incisors, both upper canines, the lower left canine, lower right central incisor, and all four first molars. Given the morphology and location of these defects, along with the developmental tim-ing of the affected teeth, such factors as molar-incisor hypomineralization, amelogenesis imperfecta, and congen-ital syphilis can likely be ruled out. The defects resulted from a nonspecific but severe physiological disturbance during the second year of life. Severe plane-form defects of this kind, where enamel formation has completely ceased, are extremely rare in premodern populations, and this example is one of the earliest reported cases. It has been suggested that these defects generally occur only in individuals that survived a life-threatening illness, which would explain the scarcity in the archaeological record, i.e., the afflicted individual would not have lived long enough for the defects to manifest. Comparisons with clinical examples and pathogen DNA analysis may provide further insight into the etiology of these defects.


2019 ◽  
Author(s):  
Helmut Spengler ◽  
Claudia Lang ◽  
Tanmaya Mahapatra ◽  
Ingrid Gatz ◽  
Klaus A Kuhn ◽  
...  

BACKGROUND Modern data-driven medical research provides new insights into the development and course of diseases and enables novel methods of clinical decision support. Clinical and translational data warehouses, such as Informatics for Integrating Biology and the Bedside (i2b2) and tranSMART, are important infrastructure components that provide users with unified access to the large heterogeneous data sets needed to realize this and support use cases such as cohort selection, hypothesis generation, and ad hoc data analysis. OBJECTIVE Often, different warehousing platforms are needed to support different use cases and different types of data. Moreover, to achieve an optimal data representation within the target systems, specific domain knowledge is needed when designing data-loading processes. Consequently, informaticians need to work closely with clinicians and researchers in short iterations. This is a challenging task as installing and maintaining warehousing platforms can be complex and time consuming. Furthermore, data loading typically requires significant effort in terms of data preprocessing, cleansing, and restructuring. The platform described in this study aims to address these challenges. METHODS We formulated system requirements to achieve agility in terms of platform management and data loading. The derived system architecture includes a cloud infrastructure with unified management interfaces for multiple warehouse platforms and a data-loading pipeline with a declarative configuration paradigm and meta-loading approach. The latter compiles data and configuration files into forms required by existing loading tools, thereby automating a wide range of data restructuring and cleansing tasks. We demonstrated the fulfillment of the requirements and the originality of our approach by an experimental evaluation and a comparison with previous work. RESULTS The platform supports both i2b2 and tranSMART with built-in security. Our experiments showed that the loading pipeline accepts input data that cannot be loaded with existing tools without preprocessing. Moreover, it lowered efforts significantly, reducing the size of configuration files required by factors of up to 22 for tranSMART and 1135 for i2b2. The time required to perform the compilation process was roughly equivalent to the time required for actual data loading. Comparison with other tools showed that our solution was the only tool fulfilling all requirements. CONCLUSIONS Our platform significantly reduces the efforts required for managing clinical and translational warehouses and for loading data in various formats and structures, such as complex entity-attribute-value structures often found in laboratory data. Moreover, it facilitates the iterative refinement of data representations in the target platforms, as the required configuration files are very compact. The quantitative measurements presented are consistent with our experiences of significantly reduced efforts for building warehousing platforms in close cooperation with medical researchers. Both the cloud-based hosting infrastructure and the data-loading pipeline are available to the community as open source software with comprehensive documentation. CLINICALTRIAL


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