Individual and combined effects of the generalist Forficula auricularia and the specialist Episyrphus balteatus on Dysaphis plantaginea - are two predators better than one?

2016 ◽  
Vol 161 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Hazem Dib ◽  
Marie Jamont ◽  
Benoît Sauphanor ◽  
Yvan Capowiez
Keyword(s):  
Combined Effects ◽  
Forficula Auricularia ◽  
Episyrphus Balteatus ◽  
Dysaphis Plantaginea ◽  
Better Than

Influence of diet on development and oviposition of Forficula auricularia (Dermaptera: Forficulidae)

2001 ◽  
Vol 133 (5) ◽  
pp. 705-708 ◽  
Author(s):  
Ghislain Berleur ◽  
Jean Gingras ◽  
Jean-Claude Tourneur
Keyword(s):  
Food Preference ◽  
Rhopalosiphum Padi ◽  
Soil Surface ◽  
Cold Weather ◽  
Forficula Auricularia ◽  
Content Analyses ◽  
European Earwig ◽  
Preference Tests ◽  
Daylight Period ◽  
Better Than

In North America, the life cycle of the European earwig (Forficula auricularia L.) can be divided into a nesting phase (hypogean phase) and a free-foraging phase (epigean phase) (Crumb et al. 1941; Behura 1956; Lamb and Wellington 1975). Adults spend the nesting phase in the soil; females burrow into the ground at the onset of the cold weather, lay eggs, and then care for the eggs. Hatching occurs in spring; first- or second-instar nymphs move to the soil surface for the free-foraging period. The earwig, a nocturnal insect, spends the entire daylight period of hiding under trash or in dark crevices. Where two broods occur, females reenter the ground a second time (Lamb and Wellington 1975). Stomach content analyses (Crumb et al. 1941; Sunderland and Vickerman 1980) and food preference tests (McLeod and Chant 1952; Buxton and Madge 1976) revealed that the European earwig is omnivorous. Under laboratory conditions, nymphs fed freshly frozen aphids, Rhopalosiphum padi (L.) (Hemiptera: Aphididae), survive better than those fed green algae or carrots, develop faster, and produce heavier females (Phillips 1981; Carrillo 1985).

Dispersion Properties of Nano-SiO2 under Single and Combined Actions of Sodium Hex Metaphosphate and Polycarboxylate Superplasticizer

2019 ◽  
Vol 956 ◽  
pp. 352-360
Author(s):  
Yao Qun Xu ◽  
Shu Guang Li ◽  
Tao Ji ◽  
Gai Xin Chen
Keyword(s):  
Linear Relationship ◽  
Dispersion Stability ◽  
Optimal Dosage ◽  
Combined Effects ◽  
Optimal Amount ◽  
Dispersion Properties ◽  
Polycarboxylate Superplasticizer ◽  
Combined Actions ◽  
The Stability ◽  
Better Than

Separate and combined effects of sodium hex metaphosphate (SHMP) and polycarboxylate superplasticizer (PCS) of different dosages (0.5%, 1%, 1.5%, and 2%) on the dispersion stability of nanoSiO2 (NS) were studied. The effect of the dispersant was characterized by the change of absorbance. When SHMP and PCS were used separately and in combination, the stability of nanoSiO2 dispersions was compared and the optimal amount of dispersant for different dosage of nanoSiO2 dispersions were summarized. Finally, the mechanism of dispersant compounding was discussed. The results show that with the increase of the concentration, the optimal amount of SHMP increases significantly while the optimal amount of PCS dispersant is lower and better than SHMP. A clear linear relationship between the optimal dosage of SHMP and the concentration of NS could be found. If SHMP is used combined with PCS, the stability of the dispersed NS will increase and the dosages of both dispersants will be reduced.

scholarly journals Individual and combined effects of verapamil or trandolapril on attenuating hypertensive glomerulopathic changes in the stroke-prone rat.

1996 ◽  
Vol 7 (5) ◽  
pp. 681-686
Author(s):  
K Münter ◽  
S Hergenröder ◽  
K Jochims ◽  
M Kirchengast
Keyword(s):  
Ace Inhibitor ◽  
Blood Pressure Reduction ◽  
Control Group ◽  
Channel Blockers ◽  
Combined Effects ◽  
Spontaneously Hypertensive ◽  
Drug Classes ◽  
Kidney Morphology ◽  
Severity Grading ◽  
Better Than

Previous studies have demonstrated differences in the progression to glomerulosclerosis with the use of calcium channel blockers (CCB). The results with angiotensin-converting enzyme (ACE) inhibitors are more consistent. Moreover, only two studies have examined the combined effects of these drug classes on the development of glomerulosclerosis. The aim of the study presented here was to test the hypothesis that nonhypotensive doses of the combination (VT) of a nondihydropyridine CCB, verapamil (V), and an ACE-inhibitor, trandolapril (T), will slow the development of glomerulosclerosis better than either agent alone in stroke-prone spontaneously hypertensive rats (SHRSP). SHRSP were randomized to treatment in one of three groups with nonhypotensive doses of these agents; a fourth group served as control (C). The control rats developed significant increases in proteinuria compared with the other groups (C, 190 +/- 35 mg.kg-1.d-1 versus VT, 19 +/- 12 mg.kg-1.d-1; P < 0.05). This finding correlated with the degree of glomerulosclerosis (mean severity grading for C, 3.31 +/- 0.21 versus VT, 1.6 +/- 0.51; P < 0.05). Moreover, there was no significant reduction in arterial pressure between these groups (C, 282 +/- 5 versus VT, 259 +/- 13 mm Hg; P = 0.12). Despite persisting hypertension, the rise in proteinuria was also attenuated in both the V group (57 +/- 21 mg.kg-1.d-1) and the T group (43 +/- 24 mg.kg-1.d-1). However, compared with the control rats, kidney morphology was unchanged. Lastly, creatinine clearance was better preserved in the VT group compared with the control group (C, 0.57 +/- 0.01 versus VT, 0.74 +/- 0.06 mL.min-1.100 g-1; P < 0.05). It was concluded that the combination of nonhypotensive doses of VT attenuates the rise in proteinuria and progression to glomerulosclerosis. This study supports the concept that VT may have effects on the glomerulus that are independent of blood pressure reduction.

Preemergence Herbicides and Cultivations for Soybeans (Glycine max)

Weed Science ◽  
1981 ◽  
Vol 29 (2) ◽  
pp. 165-168 ◽  
Author(s):  
Maurice R. Gebhardt
Keyword(s):  
Glycine Max ◽  
Weed Control ◽  
Combined Effects ◽  
Full Rate ◽  
The One ◽  
Preemergence Herbicides ◽  
Better Than

Combined effects of herbicides, herbicide rates, and cultivation for weed control in soybeans [Glycine max(L.) Merr. ‘Williams’] were studied using full and one-half rates of either chloramben (3-amino-2,5-dichlorobenzoic acid) or alachlor [2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide] + linuron [3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea] with no, one, and two cultivations. The full rate was 2.2 kg/ha for alachlor and chloramben and 0.70 kg/ha for linuron. Alachlor + linuron was better than chloramben, and the full rate was better than the one-half rate. One or two cultivations were better than no cultivation. Cultivations were more effective when used with alachlor + linuron than when used with chloramben or when used alone. Alachlor + linuron at the full rate with one or two cultivations produced the best soybean yields. A one-half rate of alachlor + linuron with one or two cultivations yielded the same as a full rate of alachlor + linuron alone or with one cultivation, chloramben at one-half rate with two cultivations, and chloramben at a full rate with two cultivations. Cultivations can be effective by increasing weed control and yields when herbicide rate or effectiveness has been reduced. Use of a cultivation in addition to the preemergence herbicides used in this study is necessary for improved weed control and yields.

scholarly journals Combined Effects of Altitude and High Temperature on Complex Performance

1972 ◽  
Vol 14 (2) ◽  
pp. 161-172 ◽  
Author(s):  
W. D. Chiles ◽  
P. F. Iampietro ◽  
E. A. Higgins
Keyword(s):  
High Temperature ◽  
Environmental Conditions ◽  
Mental Arithmetic ◽  
The Other ◽  
Combined Effects ◽  
Physiological Measures ◽  
Trained Subjects ◽  
Clear Cut ◽  
Persistent Effect ◽  
Better Than

Nine well-trained subjects were tested on a complex-performance device involving tracking, monitoring, and mental arithmetic during exposure to altitude (14,000 ft.) and heat (60° C) both singly and in combination. Several physiological measures were taken. Exposure durations were 30 min. for each condition with both pre- and posttesting. The only clear-cut effects of the conditions were significant differences across the environmental conditions on the tracking task. Altitude was clearly a more powerful variable than temperature in this study. This was evidenced by the fact that performance under the temperature-plus-altitude and the altitude-only conditions were approximately the same; performance under the temperature-only condition was significantly better than performance for either of the other two conditions. There was some evidence that the two environments in combination produced a persistent effect on performance that did not dissipate with return to normal conditions. Measured physiological functions of the subjects were within the tolerable range.

Time and Latitude in South Africa

1972 ◽  
Vol 1 ◽  
pp. 27-38
Author(s):  
J. Hers
Keyword(s):  
South Africa ◽  
Cape Town ◽  
Astronomical Observations ◽  
Royal Observatory ◽  
The Republic ◽  
Astronomical Determination ◽  
Limited Accuracy ◽  
Better Than

In South Africa the modern outlook towards time may be said to have started in 1948. Both the two major observatories, The Royal Observatory in Cape Town and the Union Observatory (now known as the Republic Observatory) in Johannesburg had, of course, been involved in the astronomical determination of time almost from their inception, and the Johannesburg Observatory has been responsible for the official time of South Africa since 1908. However the pendulum clocks then in use could not be relied on to provide an accuracy better than about 1/10 second, which was of the same order as that of the astronomical observations. It is doubtful if much use was made of even this limited accuracy outside the two observatories, and although there may – occasionally have been a demand for more accurate time, it was certainly not voiced.

Localization of immunolabels by electron microscopy and image averaging

1983 ◽  
Vol 41 ◽  
pp. 282-283
Author(s):  
J. Frank ◽  
P.-Y. Sizaret ◽  
A. Verschoor ◽  
J. Lamy
Keyword(s):  
Electron Microscopy ◽  
Single Particle ◽  
Attachment Site ◽  
Uranyl Acetate ◽  
Limulus Polyphemus ◽  
Resolution Limit ◽  
Electron Microscopic ◽  
Image Averaging ◽  
Top View ◽  
Better Than

The accuracy with which the attachment site of immunolabels bound to macromolecules may be localized in electron microscopic images can be considerably improved by using single particle averaging. The example studied in this work showed that the accuracy may be better than the resolution limit imposed by negative staining (∽2nm).The structure used for this demonstration was a halfmolecule of Limulus polyphemus (LP) hemocyanin, consisting of 24 subunits grouped into four hexamers. The top view of this structure was previously studied by image averaging and correspondence analysis. It was found to vary according to the flip or flop position of the molecule, and to the stain imbalance between diagonally opposed hexamers (“rocking effect”). These findings have recently been incorporated into a model of the full 8 × 6 molecule.LP hemocyanin contains eight different polypeptides, and antibodies specific for one, LP II, were used. Uranyl acetate was used as stain. A total of 58 molecule images (29 unlabelled, 29 labelled with antl-LPII Fab) showing the top view were digitized in the microdensitometer with a sampling distance of 50μ corresponding to 6.25nm.

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