THE RETROCEREBRAL GLANDS OF MOSQUITO LARVAE

1964 ◽  
Vol 42 (1) ◽  
pp. 39-51 ◽  
Author(s):  
J. G. Rempel ◽  
P. G. Rueffel
Keyword(s):  
Anterior Part ◽  
Comparative Morphology ◽  
Corpus Allatum ◽  
Lateral Margin ◽  
Mosquito Larvae ◽  
Corpus Cardiacum ◽  
Size And Shape ◽  
Toxorhynchites Rutilus ◽  
Two Bodies ◽  
Shape And Size

The comparative morphology of the retrocerebral gland complex of 10 genera of mosquito larvae, including 52 species, has been investigated. The complex consists of two distinct bodies attached to the transverse trachea in the anterior part of the prothorax. Each body is considered to be an association of the corpus allatum, the corpus cardiacum, and the prothoracic gland.In Aedes larvae the shape of the complex varies markedly between species and even within species. In Anopheles larvae it is elongated and flask-shaped; in Culiseta it is short and broad, ending distally in one or more line points; in Culex it is small and triangular. In Psorophora larvae it varies greatly in shape and size, being large in predacious forms, small in non-predacious; it may be sac-like or pointed at the end. In Mansonia perturbans it is small and spindle-shaped; in Wyeomyia hanyei it is small and U-shaped; in Orthopodomyia signifera, small and triangular. In Toxorhynchites rutilus, a predacious form, it is narrow and unusually large. In Opifex fusca it is triangular, with the inner lateral margin as the base.Not only may the complex vary in size and shape within a species, but even within a specimen the two bodies may differ to a remarkable degree.

Corpus Allatum and Corpus Cardiacum in Chironomus sp.

1944 ◽  
Vol 78 (778) ◽  
pp. 472-477 ◽  
Author(s):  
H. C. Zee ◽  
S. Pai
Keyword(s):  
Corpus Allatum ◽  
Corpus Cardiacum

Predicted versus expressed adipokinetic hormones, and other small peptides from the corpus cardiacum–corpus allatum: A case study with beetles and moths

Peptides ◽  
2008 ◽  
Vol 29 (7) ◽  
pp. 1124-1139 ◽  
Author(s):  
Gerd Gäde ◽  
Heather G. Marco ◽  
Petr Šimek ◽  
Neil Audsley ◽  
Kevin D. Clark ◽  
...  
Keyword(s):  
Corpus Allatum ◽  
Corpus Cardiacum ◽  
Small Peptides

Cooling Rates of Brake Drums and Discs

1965 ◽  
Vol 180 (1) ◽  
pp. 191-205 ◽  
Author(s):  
T.P. Newcomb ◽  
N. Millner
Keyword(s):  
Cooling Rate ◽  
Air Flow ◽  
Vehicle Speed ◽  
Uniform Temperature ◽  
Cooling Rates ◽  
Size And Shape ◽  
Slip Ring ◽  
Disc Brakes ◽  
Shape And Size ◽  
Time Plot

An investigation has been made of the rates of cooling of vehicle brake drums and discs. Thermocouples were inserted in the drums and discs and in the wheel hubs and their outputs fed via slip ring units to meters mounted inside the vehicle. The drums or discs were heated to a uniform temperature of 300°-400°C by drag braking and the rate at which they cooled measured while the vehicle was driven at constant speed. Measurements were made at various speeds in the range 0 to 90 mile/h. From the log (temperature) against time plot a cooling coefficient bv was determined. It is shown that at a vehicle speed v the quantity bv can be expressed in the form bv = b0 +Kv0·8 where b0 represents the loss of heat to the hub and K is a constant depending on the size and shape of the drum or disc. Values of these constants have been determined on a variety of cars having discs and drums varying from 7 in to 11 in diameter and on a lorry fitted with 16·75 in diameter drums. Cooling rates are shown to depend on shape and size of the disc or drum. Results show that the cooling rates of front brakes are about 20 per cent higher than the rear brakes and that front discs cool about 25 per cent more quickly than the corresponding drum size recommended for the same vehicle. The cooling rate of front discs did not change when wire wheels were fitted instead of solid wheels. Ventilated discs and solid discs were also compared. The effect of fitting dust shields on disc brakes is shown to reduce the cooling rates by about 30 per cent. The effect of otherwise disturbing the air flow was studied.

Synthesis and characterization of size- and shape-controlled silver nanoparticles

2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Suparna Mukherji ◽  
Sharda Bharti ◽  
Gauri Shukla ◽  
Soumyo Mukherji
Keyword(s):  
Silver Nanoparticles ◽  
Nucleation And Growth ◽  
Detailed Review ◽  
Size And Shape ◽  
Physical Chemical ◽  
Application Potential ◽  
Shape Controlled ◽  
Synthesis Routes ◽  
Shape And Size

Abstract Silver nanoparticles (AgNPs) have application potential in diverse areas ranging from wound healing to catalysis and sensing. The possibility for optimizing the physical, chemical and optical properties for an application by tailoring the shape and size of silver nanoparticles has motived much research on methods for synthesis of size- and shape-controlled AgNPs. The shape and size of AgNPs are reported to vary depending on choice of the Ag precursor salt, reducing agent, stabilizing agent and on the synthesis technique used. This chapter provides a detailed review on various synthesis approaches that may be used for synthesis of AgNPs of desired size and shape. Silver nanoparticles may be synthesized using diverse routes, including, physical, chemical, photochemical, biological and microwave -based techniques. Synthesis of AgNPs of diverse shapes, such as, nanospheres, nanorods, nanobars, nanoprisms, decahedral nanoparticles and triangular bipyramids is also discussed for chemical-, photochemical- and microwave-based synthesis routes. The choice of chemicals used for reduction and stabilization of nanoparticles is found to influence their shape and size significantly. A discussion on the mechanism of synthesis of AgNPs through nucleation and growth processes is discussed for AgNPs of varying shape and sizes so as to provide an insight on the various synthesis routes. Techniques, such as, electron microscopy, spectroscopy, and crystallography that can be used for characterizing the AgNPs formed in terms of their shape, sizes, crystal structure and chemical composition are also discussed in this chapter. Graphical Abstract:

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