First approximation to a phenology of the honeybees (Apis mellifera) and flora of Africa

Oecologia ◽  
1995 ◽  
Vol 101 (3) ◽  
pp. 265-273 ◽  
Author(s):  
H. R. Hepburn ◽  
S. E. Radloff
Keyword(s):  
Apis Mellifera ◽  
First Approximation ◽  
Flora Of Africa

Differentiation Processes of the Ocellar Retina of the Honeybee (Apis Mellifera L.)

1990 ◽  
Vol 48 (3) ◽  
pp. 430-431
Author(s):  
Maria Anna Pabst
Keyword(s):  
Apis Mellifera ◽  
Distal Part ◽  
Cell Layer ◽  
Single Layer ◽  
Photoreceptor Cells ◽  
Distal Segment ◽  
Compound Eyes ◽  
Thin Sections ◽  
Ultrastructural Studies ◽  
Adult Worker

In addition to the compound eyes, honeybees have three dorsal ocelli on the vertex of the head. Each ocellus has about 800 elongated photoreceptor cells. They are paired and the distal segment of each pair bears densely packed microvilli forming together a platelike fused rhabdom. Beneath a common cuticular lens a single layer of corneagenous cells is present.Ultrastructural studies were made of the retina of praepupae, different pupal stages and adult worker bees by thin sections and freeze-etch preparations. In praepupae the ocellar anlage consists of a conical group of epidermal cells that differentiate to photoreceptor cells, glial cells and corneagenous cells. Some photoreceptor cells are already paired and show disarrayed microvilli with circularly ordered filaments inside. In ocelli of 2-day-old pupae, when a retinogenous and a lentinogenous cell layer can be clearly distinguished, cell membranes of the distal part of two photoreceptor cells begin to interdigitate with each other and so start to form the definitive microvilli. At the beginning the microvilli often occupy the whole width of the developing rhabdom (Fig. 1).

Psychological literacy: A first approximation.

1990 ◽  
Vol 45 (7) ◽  
pp. 891-900 ◽  
Author(s):  
C. Alan Boneau
Keyword(s):  
First Approximation

Benefits of performing learning flights in honeybees, Apis mellifera

2003 ◽  
Author(s):  
Cynthia A. Wei ◽  
Fred C. Dyer
Keyword(s):  
Apis Mellifera

Rapid evaluation of FDG imaging alternatives using head-to-head comparisons of full ring and gamma camera based PET scanners –

2002 ◽  
Vol 41 (05) ◽  
pp. 208-213 ◽  
Author(s):  
L. M. Haslinghuis-Bajan ◽  
L. Hooft ◽  
A. van Lingen ◽  
M. van Tulder ◽  
W. Devillé ◽  
...  
Keyword(s):  
Methodological Quality ◽  
Gamma Camera ◽  
First Generation ◽  
Prospective Evaluation ◽  
First Approximation ◽  
Variable Head ◽  
Malignant Lesions ◽  
The Impact ◽  
Pet Scanners

SummaryAim: While FDG full ring PET (FRPET) has been gradually accepted in oncology, the role of the cheaper gamma camera based alternatives (GCPET) is less clear. Since technology is evolving rapidly, “tracker trials” would be most helpful to provide a first approximation of the relative merits of these alternatives. As difference in scanner sensitivity is the key variable, head-to-head comparison with FRPET is an attractive study design. This systematic review summarises such studies. Methods: Nine studies were identified until July 1, 2000. Two observers assessed the methodological quality (Cochrane criteria), and extracted data. Results: The studies comprised a variety of tumours and indications. The reported GC- and FRPET agreement for detection of malignant lesions ranged from 55 to 100%, but with methodological limitations (blinding, standardisation, limited patient spectrum). Mean lesion diameter was 2.9 cm (SD 1.8), with only about 20% <1.5 cm. The 3 studies with the highest quality reported concordances of 74-79%, for the studied lesion spectrum. Contrast at GCPET was lower than that of FRPET, contrast and detection agreement were positively related. Logistic regression analysis suggested that pre-test indicators might be used to predict FRPET-GCPET concordance. Conclusion: In spite of methodological limitations, “first generation” GCPET devices detected sufficient FRPET positive lesions to allow prospective evaluation in clinical situations where the impact of FRPET is not confined to detection of small lesions (<1.5 cm). The efficiency of head-to-head comparative studies would benefit from application in a clinically relevant patient spectrum, with proper blinding and standardisation of acquisition procedures.

УГРОЗЫ РАСПРОСТРАНЕНИЯ ВИРУСНЫХ ИНФЕКЦИЙ У ПЧЕЛ (Apis mellifera L.) И РОЛЬ КЛЕЩА Varroa destructor В РАЗВИТИИ ПАТОЛОГИЙ

2016 ◽  
Vol 51 (2) ◽  
pp. 156-171
Author(s):  
А.В. СПРЫГИН ◽  
◽  
Ю.Ю. БАБИН ◽  
Е.М. ХАНБЕКОВА ◽  
Л.Е. РУБЦОВА ◽  
...  
Keyword(s):  
Apis Mellifera ◽  
Varroa Destructor

Effects of simulated heat waves on honeybees (Apis mellifera)

2016 ◽  
Author(s):  
Célia Bordier
Keyword(s):  
Apis Mellifera ◽  
Heat Waves
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