Larval growth and development of the stonefly Pteronarcys californica (Insecta: Plecoptera) in the Crowsnest River, Alberta

1998 ◽  
Vol 76 (12) ◽  
pp. 2274-2280 ◽  
Author(s):  
G D Townsend ◽  
G Pritchard
Keyword(s):  
Aquatic Insects ◽  
Larval Growth ◽  
Adult Emergence ◽  
Head Capsule ◽  
Life Cycles ◽  
Embryonic Diapause ◽  
Larval Recruitment ◽  
Summer Diapause ◽  
History Of ◽  
High Degree

We used head-capsule width, wing-pad length, larval recruitment, adult emergence, and MULTIFANTM analysis to determine the life history of the stonefly Pteronarcys californica in the Crowsnest River, Alberta. Embryonic development, incorporating an early diapause, accounts for approximately 1 year of the life cycle. Both sexes spend a further 4 years in the larval stage. Female larvae grow faster than males and so achieve a larger size at emergence. Extended larval recruitment leads to variation in the sizes of larvae of the same year class and probably to cohort splitting. There is a high degree of synchrony in adult emergence, perhaps as a result of a summer diapause in antepenultimate-instar larvae. These phenomena (embryonic diapause, extended larval recruitment, different growth rates of the sexes, cohort splitting, and larval diapause) are possibly typical of aquatic insects with long life cycles.

Control of summer and winter diapause in Pidorus euchromioides (Lepidoptera: Zygaenidae) on Chinese sweetleaf Symplocos chinensis

1998 ◽  
Vol 88 (2) ◽  
pp. 207-211 ◽  
Author(s):  
Xue Fangsen ◽  
H. G. Kallenborn
Keyword(s):  
First Generation ◽  
Larval Instar ◽  
Larval Growth ◽  
Growth Period ◽  
Day Length ◽  
Strongly Correlated ◽  
Summer Diapause ◽  
Unpredictable Environment ◽  
High Degree ◽  
Short Days

AbstractPidorus euchromioides Walker has two separate diapauses during its life cycle, a winter diapause as a fourth larval instar and a summer diapause as a prepupa in a cocoon. Winter diapause was induced by short photoperiods. The critical day length of 13 h 20 min to 13 h 40 min at 23.3°C under insectary conditions was very similar to the critical day length (13 h 32 min) observed in the field. Sensitivity to day length was restricted to the first 9 days, corresponding to the first and second instars. The duration of larval diapause was not only strongly correlated with the inducing photoperiod, but also dependent on the number of short days experienced during the larval growth period. The shortest diapause occurred at the critical day length, or when the larvae were exposed for 6 days (a critical number of short days) to a photoperiod of LD 12 h:12 h. The summer diapause appeared to be primarily determined by a genetic factor and only occurred in part of the overwintering generation and the first generation. The two different diapause mechanisms play important roles. Winter diapause ensures that P. euchromioides synchronizes its development and activity with the phenology of specific host plants, and summer diapause provides the species with a high degree of adaptation to an unpredictable environment.

Life histories of some Benthic invetebrates form streams of the Northern Jarrah Forest, Western Australia

1988 ◽  
Vol 39 (6) ◽  
pp. 785 ◽  
Author(s):  
SE Bunn
Keyword(s):  
Life History ◽  
Life Histories ◽  
Adult Emergence ◽  
Adaptive Strategy ◽  
Life Cycles ◽  
Jarrah Forest ◽  
Stream Insects ◽  
Long Period ◽  
Life History Pattern ◽  
High Degree

Life history patterns of thirteen species of invertebrates from streams of the northern jarrah forest were examined over a 1-year period. Five species had univoltine cycles with a single cohort and demonstrated a high degree of synchrony of larval development and a restricted period of adult emergence. Two species of Leptophlebiidae also had univoltine cycles but showed the more typical pattern of Australian mayflies, with extended recruitment, multiple overlapping cohorts and a long period of adult emergence. Uroctena sp., a small gammarid, had a generation time of 1 year but showed considerable spatial variation in the degree of synchrony of development. This appeared to be a result of differences in the constancy of stream discharge and was not attributable to differences in the temperature regime of the streams. At least three species demonstrated cohort splitting which resulted in an apparently bivoltine cycle. A life-history pattern of alternating long and short development times is described which, on average, would produce two generations every 3 years. This is considered to be a highly adaptive strategy for Australian stream insects with slow life cycles and can explain the extended periods of recruitment and adult emergence so often observed. Streams of the northern jarrah forest are depauperate compared with other Australian streams, despite predictable temperature and discharge regimes. The insular nature of the south-west Bassian region and its long period of isolation may be the principle cause of this reduced diversity. The invertebrate community of these streams is simple in structure and has a high degree of seasonality that is atypical of the temperate streams of Australia and New Zealand.

Gregarine infection accelerates larval development of the cat fleaCtenocephalides felis(Bouché)

Parasitology ◽  
2017 ◽  
Vol 144 (4) ◽  
pp. 419-425 ◽  
Author(s):  
M. E. ALARCÓN ◽  
A. JARA-F. ◽  
R. C. BRIONES ◽  
A. K. DUBEY ◽  
C. H. SLAMOVITS
Keyword(s):  
Control Strategies ◽  
Life Cycles ◽  
Arms Race ◽  
Control Group ◽  
Symbiotic Relationship ◽  
Cat Flea ◽  
Evolutionary Scenario ◽  
Potential Development ◽  
History Of ◽  
High Degree

SUMMARYA high degree of specialization between host and parasite is a well-known outcome of a long history of coevolution, and it is strikingly illustrated in a coordination of their life cycles. In some cases, the arms race ensued at the establishment of a symbiotic relationship results in the adoption of manipulative strategies by the parasite. We have already learned thatSteinina ctenocephali, a gregarine living in the alimentary canal of cat flea,Ctenocephalides felisfollows its phenology and metamorphosis. Despite these findings the outcome of their symbiotic partnership (mutualist, parasitic or commensal) remains unclear. To address this important question, we measured life history parameters of the flea in the presence of varying infection intensities of gregarine oocysts in laboratory conditions. We found that neither the emergence nor survival rate of fleas was affected by harbouring the gregarines. More surprisingly, our results show that flea larvae infected with gregarines developed faster and emerged earlier than the control group. This gregarine therefore joins the selected group of protists that can modify physiological host traits and provides not only new model taxa to be explored in an evolutionary scenario, but also potential development of control strategies of cat flea.

Development of larvae of the whitefringed weevil,Graphognathus leucoloma(Coleoptera: Curculionidae), in northern Queensland

1991 ◽  
Vol 81 (4) ◽  
pp. 385-393 ◽  
Author(s):  
N. Gough ◽  
J.D. Brown
Keyword(s):  
Larval Growth ◽  
Adult Emergence ◽  
Head Capsule ◽  
Larval Survival ◽  
Early Summer ◽  
Lablab Purpureus ◽  
Mild Winter ◽  
Pasture Legumes ◽  
First Instar ◽  
Summer Temperatures

AbstractGrowth of larvae of the whitefringed weevil,Graphognathus leucoloma(Boheman), was studied in the laboratory and on various crops in pots in a shadehouse at Kairi, on the Atherton Tableland in north Queensland. In the laboratory at 25.5 ± 1°C there were 11 instars for which head capsule widths and weights were recorded. The first instar weighed 0.14 mg. This was a non-feeding stage capable of prolonged survival, and after 10 weeks in soil without food 60% survived. When provided with carrot (Daucus carota) larvae grew to 2 or 3 mg after 6 to 7 weeks, then increased rapidly in weight reaching 140 mg after 120 days. At 25.5°C the average time from first instar to adult was 311 days, due in part to a long prepupal period. Larval growth was measured on the roots of peanut (Arachis hypogaea) plants in pots in summer and winter. Under summer conditions (mean soil temperature 23.3°C) larvae reached 140 mg in about 120 days, similar to that in the laboratory on carrot. These fully grown larvae remained in the pots over the mild winter without pupating. Larvae developing in autumn/winter grew more slowly, but the fully grown larvae were then exposed to high spring (early summer) temperatures and soon pupated, the average time from first instar to adult being 273 days. The indications are that temperatures above 25°C quickly precondition mature larvae from Tolga for pupation, thus explaining the broad timing of adult emergence in the field in north Queensland. On different plants common near Tolga, larvae grew most quickly on peanuts and on the pasture legumes dolichos (Lablab purpureus) and stylosanthes (Stylosanthes guianensis). Survival on maize equalled that on peanuts (46.5% in sterilized soil) but growth was less. Larval survival and growth on the grass crowsfoot (Eleusine indica), and (surprisingly) on the pasture legume glycine (Neonotonia wightii) was very poor.

THE R.J. CHAMBERS COLLECTION: AN “ARCHIVIST'S” REVELATIONS OF 20th CENTURY ACCOUNTING THOUGHT AND PRACTICE

2006 ◽  
Vol 33 (1) ◽  
pp. 145-166 ◽  
Author(s):  
Graeme W. Dean ◽  
Peter W. Wolnizer ◽  
Frank L. Clarke
Keyword(s):  
Prima Facie ◽  
Accounting Education ◽  
Hard Copy ◽  
Accounting History ◽  
Research Areas ◽  
Archival Source ◽  
Inflation Accounting ◽  
History Of ◽  
High Degree ◽  
Accounting Standard Setting

A major, unique accounting archival source, the R.J. Chambers Collection comprises both hard copy and, utilizing cutting-edge search technology, internet accessible materials. From his academic beginnings, Chambers was an orderly person, an archivist of the extensive and varied evidence that underpinned his proposals for accounting reform. Opening research areas for accounting biography, the development of accounting thought, the history of accounting institutions, prosopography, public sector accounting history, and comparative international accounting history are foremost amongst the myriad justifications for seeking to unravel the accounting history “lodes” in archives such as the Goldberg, Chambers, and Briloff Collections [Potter, 2003]. The archiving of the meticulously kept Chambers papers from 1947–1999 provides an opportunity for unfolding the background to events previously withheld from accounting history scholars. Professional episodes in relation to inflation accounting, standard setting, proposals to reform accounting education, and the like that appeared prima facie to be worth investigating are now open to scrutiny from a different angle, with a different type of evidence available in this Collection. This Collection provides a high degree of archival provenance. In particular, it represents an orderly retention of past documentation of what Chambers wrote, and perhaps uniquely for accounting historians, received; thus, providing an extensive window from which to examine the disorderly present environment of acounting.

scholarly journals Euglycemic Diabetic Ketoacidosis after a Single Dose of Empagliflozin in a Patient with Pancreatitis

2021 ◽  
Vol 11 (2) ◽  
pp. 216-218
Author(s):  
Marta Brandão Calçada ◽  
Luís Fernandes ◽  
Rita Soares Costa ◽  
Sara Montezinho ◽  
Filipa Martins Duarte ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Diabetic Ketoacidosis ◽  
Drug Class ◽  
Clinical Suspicion ◽  
Laboratory Findings ◽  
Sodium Glucose Cotransporter ◽  
History Of ◽  
High Degree ◽  
Euglycemic Diabetic Ketoacidosis

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are the most recently approved drug class for the treatment of type 2 diabetes mellitus (T2D). Although they are largely well-tolerated, their intake has been associated with euglycemic diabetic ketoacidosis (DKA) in some rare cases. We report the case of a 70-year-old male with type 2 diabetes and no history of DKA, who started therapy with empagliflozin one day before presenting with acute pancreatitis and laboratory findings consistent with euglycemic DKA. SGLT2i can induce euglycemic DKA from the first dose. Given the atypical presentation, a high degree of clinical suspicion is required to recognize this complication.

929 Not Another Abscess - A Case of Streptococcal Myositis Misdiagnosed as a Right Axillary Abscess

2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
O Oyende ◽  
J Jackman
Keyword(s):  
White Cell Count ◽  
General Surgeon ◽  
High Dose ◽  
General Anaesthetic ◽  
Microbiological Analysis ◽  
Reactive Protein ◽  
Affected Tissue ◽  
Life Threatening ◽  
History Of ◽  
High Degree

Abstract Introduction Streptococcal myositis is a rare form of infectious myositis caused by Lansfield A beta-haemolytic streptococci. It is characterised by rapidly spreading inflammation that can result in severe systemic toxicity and necrosis of the affected tissue if not diagnosed and aggressively treated. Presentation We report a case of a 42-year-old male who presented with a one-week history of worsening right axillary swelling that progressed to painful swelling of his arm. Inflammatory markers were significantly elevated with a white cell count of 17 ×109/L and C-reactive protein of 212 mg/L. On examination, a fluctuant axillary swelling was appreciated, and a decision was made for incision and drainage under general anaesthetic. Intraoperative aspiration of his arm revealed copious purulent fluid prompting intraoperative orthopaedic consult and exploration of the anterior compartment in which there was extensive involvement of the biceps muscle. The microbiological analysis revealed gram-positive cocci in chains, and microbiology advice sought for tailoring of antibiotic regimen. He has recovered well. Discussion Though uncommon, the emergency general surgeon should have a high degree of suspicion when evaluating soft tissue infections to avert potentially disastrous outcomes. Conclusion Early diagnosis, aggressive management with high-dose intravenous antibiotics, and surgical debridement are principles to treat this rare, life-threatening infection.

scholarly journals The Return of National Self-Sufficiency? Excavating Autarkic Thought in a De-Globalizing Era

2021 ◽  
Author(s):  
Eric Helleiner
Keyword(s):  
Intellectual History ◽  
International Political Economy ◽  
Economic Thought ◽  
John Maynard Keynes ◽  
New Politics ◽  
Self Sufficiency ◽  
National Economic ◽  
History Of ◽  
High Degree ◽  
Rich History

Abstract As the global crisis triggered by the COVID-19 virus unfolded, The Economist magazine published a cover in May 2020 titled “Goodbye globalization: the dangerous lure of self-sufficiency.” The title summed up well the new political interest in the ideology of national economic self-sufficiency in the pandemic context. Unfortunately, contemporary textbooks in the field of international political economy (IPE) say little about this kind of “autarkic” thought. No survey of the history of autarkic thought exists even within specialist IPE literature or in the fields of intellectual history and the history of economic thought. Filling this gap in existing scholarship, this article highlights a rich history of autarkic thought that includes the ideas of famous thinkers such as Jean-Jacques Rousseau, Johann Fichte, Mohandas Gandhi, and John Maynard Keynes. Three core rationales for a high degree of national self-sufficiency have been advanced in the past: (1) insulation from foreign economic influence, (2) insulation from foreign political and/or cultural influence, and (3) the promotion of international peace. At the same time, considerable disagreements have existed among autarkists about some of these rationales and their relative importance, as well as about the precise meaning of national self-sufficiency. These disagreements stemmed not just from differences in their specific goals but also from the different conditions across time and space in which autarkic thought was developed. In addition to improving understanding of the autarkic ideological tradition, this article contributes to emerging scholarship attempting to overcome Western-centrism in IPE scholarship as well as literature exploring the new politics of de-globalization in the current era.

scholarly journals Multi-Locus Selection and the Structure of Variation at the white Gene of Drosophila melanogaster

Genetics ◽  
1996 ◽  
Vol 144 (2) ◽  
pp. 635-645 ◽  
Author(s):  
David A Kirby ◽  
Wolfgang Stephan
Keyword(s):  
Drosophila Melanogaster ◽  
White Gene ◽  
Transcriptional Unit ◽  
North American Population ◽  
Evolutionary Mechanisms ◽  
Locus Selection ◽  
Neutral Equilibrium ◽  
History Of ◽  
High Degree ◽  
Very High

Abstract We surveyed sequence variation and divergence for the entire 5972-bp transcriptional unit of the white gene in 15 lines of Drosophila melanogaster and one line of D. simulans. We found a very high degree of haplotypic structuring for the polymorphisms in the 3′ half of the gene, as opposed to the polymorphisms in the 5′ half. To determine the evolutionary mechanisms responsible for this pattern, we sequenced a 1612-bp segment of the white gene from an additional 33 lines of D. melanogaster from a European and a North American population. This 1612-bp segment encompasses an 834bp region of the white gene in which the polymorphisms form high frequency haplotypes that cannot be explained by a neutral equilibrium model of molecular evolution. The small number of recombinants in the 834bp region suggests epistatic selection as the cause of the haplotypic structuring, while an investigation of nucleotide diversity supports a directional selection hypothesis. A multi-locus selection model that combines features from both-hypotheses and takes the recent history of D. melanogaster into account may be the best explanation for these data.

scholarly journals Tuberculosis presenting as dacryoadenitis in the USA

2019 ◽  
Vol 12 (11) ◽  
pp. e231694 ◽  
Author(s):  
Harry Ross Powers ◽  
Mark Anthony Diaz ◽  
Julio C Mendez
Keyword(s):  
Correct Diagnosis ◽  
Developed Countries ◽  
Histopathological Analysis ◽  
Orbital Mass ◽  
Antituberculosis Therapy ◽  
The Usa ◽  
History Of ◽  
Patient’S History ◽  
High Degree ◽  
Filipino Woman

A 25-year-old Filipino woman living in the USA was evaluated for a 5-month history of left eye pain and a subsequent orbital mass. Histopathological analysis of the lacrimal mass showed a mixed inflammatory process with necrotising granulomas and positive cultures for Mycobacterium tuberculosis. She was treated with antituberculosis therapy, with resolution of symptoms. Tuberculosis dacryoadenitis is extremely rare in the USA and other developed countries. It requires a high degree of clinical suspicion with special attention to the patient’s history to make the correct diagnosis. It can be treated successfully with antituberculosis therapy.

Sign in / Sign up

Export Citation Format

Share Document