scholarly journals Aedes albopictus life table: environment, food, and age dependence survivorship and reproduction in a tropical area

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Guzhen Cui ◽  
Saifeng Zhong ◽  
Tuquan Zheng ◽  
Zhangrui Li ◽  
Xu Zhang ◽  
...  
Keyword(s):  
Life Table ◽  
Aedes Albopictus ◽  
Environmental Conditions ◽  
Tap Water ◽  
Adult Emergence ◽  
Egg Mass ◽  
Larval Rearing ◽  
Pupation Rate ◽  
Age Dependent ◽  
The Mean

Abstract Background Environmental conditions affect the biology of mosquito vectors. Aedes albopictus is a major vector of many important diseases including dengue, Zika, and chikungunya in China. Understanding the development, fecundity, and survivorship of Ae. albopictus mosquitoes in different environmental conditions is beneficial for the implementation of effective vector control measures. Methods Aedes albopictus larval and adult life-table experiments were conducted under natural conditions in indoor, half-shaded, and fully shaded settings, simulating the three major habitat types in Hainan Province, a tropical island in the South China Sea. Temperature, humidity, and light intensity were recorded daily. Larval rearing used habitat water and tap water, with and without additional artificial food. Development time, survivorship, pupation rate, and adult emergence rates were monitored. Adult mosquito survivorship and fecundity were monitored daily and reproductive rates were determined, and age-dependent survivorship and reproduction were analyzed. Results The pupation time and male and female emergence times were significantly shorter in indoor conditions than in shaded and half-shaded conditions for both tap water with added food and habitat water with added food groups. For habitat water with added food, the shaded environment had the lowest pupation rate among the settings. For tap water with added food group, the shaded environment had the lowest pupation rate. The mean survival time of females was 27.3 ± 0.8 days in the indoor condition, which was significantly longer than that in the half-shaded (18.4 ± 0.6 days) and shaded (13.8 ± 1.2 days) conditions. Adult mortality was age-dependent, and the rate of change in mortality with age was not significantly different among different environmental conditions. The mean net replacement rate (R0) of female mosquitoes showed no significant difference among the three conditions, whereas the per capita intrinsic growth rate (r) in the shaded condition was 42.0% and 20.4% higher than that in the indoor and half-shaded conditions, respectively. Female daily egg mass was also age-dependent in all the settings, decaying exponentially with age. Conclusions Our results imply that half-shaded conditions are likely the best natural condition for adult emergence and female reproduction, and food supply is crucial for larval development and pupation. The results provide new avenues for integrated mosquito management in indoor and outdoor areas, especially in half-shaded areas. Graphical Abstract

REPRODUCTIVE BIOLOGY AND BEHAVIOR OF TELENOMUS CALVUS (HYMENOPTERA: SCELIONIDAE), A PHORETIC EGG PARASITOID OF PODISUS MACULIVENTRIS (HEMIPTERA: PENTATOMIDAE)

1986 ◽  
Vol 118 (10) ◽  
pp. 1063-1072 ◽  
Author(s):  
D.B. Orr ◽  
J.S. Russin ◽  
D.J. Boethel
Keyword(s):  
Adult Emergence ◽  
Intrinsic Rate ◽  
Egg Parasitoid ◽  
Natural Increase ◽  
Egg Mass ◽  
Podisus Maculiventris ◽  
Progeny Production ◽  
Female Progeny ◽  
The Mean ◽  
And Behavior

AbstractThe behavior, reproductive capability, and longevity of Telenomus calvus Johnson, a phoretic egg parasitoid of the spined soldier bug, Podisus maculiventris (Say), were examined in the laboratory. Telenomus calvus females were observed at 25 different locations on hosts’ bodies; preferred sites were pronota and femora. Attachment to hosts was facilitated by greatly enlarged arolia. Parasitoids dismounted from hosts at the time of oviposition to parasitize egg masses. Production of female progeny by parasitoids in phoretic association with hosts peaked on the 1st day after adult emergence, then declined steadily until day 6; male progeny production remained relatively low and constant over the same period. The mean (± SE) number of progeny produced by T. calvus females was 22.4 ± 3.0. Such a small egg complement enabled most females not in phoretic association, and presented with a fresh egg mass daily, to oviposit all or nearly all of their eggs in the first host egg mass encountered. The intrinsic rate of natural increase for T. calvus in phoretic association was estimated as 0.149 ♀ ♀−1 day−1, resulting in a doubling time of 4.65 days. Longevity on non-ovipositing females with access to honey was 33.7 ± 1.1 days, but declined sharply to 5.7 ± 0.4 days when in phoretic association with hosts. Pre-imaginal development of T. calvus was restricted to host eggs that were ≤12h old, despite continued observed oviposition attempts in older host masses. These results are discussed with regard to the biology of T. calvus as a phoretic parasitoid and to its importance as a parasitoid of P. maculiventris in Louisiana.

scholarly journals Activity of Some Plant and Fungal Metabolites Towards Aedes Albopictus (Diptera, Culicidae)

2020 ◽  
Author(s):  
Sonia Ganassi ◽  
Marco Masi ◽  
Pasqualina Grazioso ◽  
Antonio Evidente ◽  
Antonio De Cristofaro
Keyword(s):  
Aedes Albopictus ◽  
Mosquito Control ◽  
Adult Emergence ◽  
Post Treatment ◽  
Fungal Metabolites ◽  
Plant Metabolites ◽  
Control Programs ◽  
First Instar ◽  
The Mean ◽  
Third Instar Larvae

Abstract Background: Aedes albopictus (Skuse), a globally spread species, vector of important human arboviruses, and of Zika virus, is extremely difficult to control even for the onset of resistances to chemicals insecticides. Ecofriendly biopesticides for vector control are urgently needed. In this study, the activity of some plant metabolites as Amaryllidaceae alkaloids and some their semisynthetic derivatives and 2-methoxy-1,4-naphthoquinones, and two analogues, and of the fungal metabolites cyclopaldic acid and epi-epoformin on the development and survival of Ae. albopictus larvae was evaluated. Methods: A preliminary screening, on first-instar larvae, with lycorine semisynthetic derivatives and cyclopaldic acid at 100 ppm was conducted. The living larvae were recorded 24 and 48 h post treatment. Based on the results, first-instar larvae were exposed to increasing doses of the compounds tested until adult emergence. The mean larval and pupal duration was calculated. Third instar larvae were exposed to increasing doses of naphthoquinones for 72 h. The mortality rates were recorded every 24. The larvicide Device® SC-15 was used as control.Results: First instar larval exposure to cyclopaldic acid at 50 and 100 ppm for 48 h, resulted in mortality mean percentage of 82.444 and 96.889% respectively; LC50 and LC90 were 40.119 and 105.092 ppm. 1,2-O,O-diacetyllycorine at 50 ppm, 48h post-treatment caused 84.667% mean percentage mortality with LC50 27.769 and LC90 88.316 ppm. Significant differences in the larval and pupal duration were proved when larvae were exposed to cyclopaldic acid (H=16.386; df 4; P=0.003; H=31.835; df 4; P=0.000), 1,2-O,O-diacetyllycorine (H=9.044; df 3; P=0.029; H=18.115; df 3; P=0.000) and N-methyllycorine iodide (H=19.457; df 4; P=0.001; H=15.400; df 4; P=0.004).Statistical analyses revealed that the number of third-instar larvae surviving to naphthoquinones significantly decreases over the time when exposed to 2-methyl-1,4-naphthoquinone 12.5, 25, 50 ppm; 2-hydroxy-1,4-naphthoquinone 12.5, 25 ppm, 2-metoxy-1,4-naphthoquinone 50 ppm. The mean number of surviving larvae exposed to: 2-methyl-1,4-naphthoquinone 12.5, 25, 50, 100 ppm, 2-hydroxy-1,4-naphthoquinone 25, 50, 100 ppm, 2-metoxy-1,4-naphthoquinone 50, 100 ppm was significantly lower than the number of correspondent control larvae, respectively.Conclusions: This study indicated that 1,2-O,O’-diacetyllycorine, N-methyllycorine iodide, cyclopaldic acid and 1,4-naphtoquinone structural derivatives have good potential to develop bioinsecticides for mosquito control programs.

scholarly journals Variation and significance of egg mass in a Pied Flycatcher Ficedula hypoleuca population in subalpine habitats in Swedish Lapland

Ornis Svecica ◽  
2015 ◽  
Vol 25 (3–4) ◽  
pp. 119-130
Author(s):  
N. Erik I. Nyholm
Keyword(s):  
Ambient Temperature ◽  
Environmental Conditions ◽  
Egg Production ◽  
Production Capacity ◽  
Ficedula Hypoleuca ◽  
Pied Flycatcher ◽  
Egg Mass ◽  
Mass Variation ◽  
Egg Formation ◽  
The Mean

Newly laid eggs of Pied Flycatchers Ficedula hypoleuca breeding in subalpine birch forest in Swedish Lapland were weighed in the field in 1965–1976. The main objective of the study was to get knowledge of the egg production capacity and its relation to the environmental conditions in the northern periphery of the breeding range of the species. The eggs were on average smaller than what is known from other Pied Flycatcher populations. Egg mass was non-linearly related to ambient temperature, and smallest at temperatures <10°C. About 70% of the eggs were laid at those temperatures. Variation in temperatures during the egg formation contributed to a significant egg mass variation between years. Average egg mass was lowest in the biggest clutches (7 or 8 eggs). Egg mass did not vary significantly within clutches, was not significantly related to the female mass, and did not vary between years in the same female. Hatching and fledging success were non-significantly related to the mean egg masses, indicating that egg sizes were not decisive for the breeding output.

Age does not necessarily influence latency of event-related potentials

2014 ◽  
Vol 33 (10) ◽  
pp. 723-727
Author(s):  
M. Westermann ◽  
I. W. Husstedt ◽  
A. Okegwo ◽  
S. Evers
Keyword(s):  
Normal Values ◽  
Rank Correlation ◽  
Event Related Potentials ◽  
Intrinsic Property ◽  
Total Sample ◽  
Oddball Paradigm ◽  
Age Dependent ◽  
Related Potentials ◽  
The Mean ◽  
P3 Component

SummaryEvent-related potentials (ERP) are regarded as age dependent. However, it is not known whether this is an intrinsic property of ERP or an extrinsic factor. We designed a setting in which ERP were evoked using a modified oddball paradigm with highly differentiable and detectable target and non-target stimuli. A total of 98 probands were enrolled in this study. We evaluated the latency and amplitude of the P3 component of visually evoked ERP. The mean P3 latency was 294 ± 28 ms and was not related to age (r = –0.089; p = 0.382; Spearman-rank-correlation). The P3 amplitude was related to age in the total sample (r = –0.323; p = 0.001; Spearmanrank-correlation) but not in the probands under the age of 60 years. There were no significant differences regarding sex. Our findings suggest that ERP are not age dependent if highly differentiable and detectable stimuli are used. This should be considered when normal values of ERP are created for clinical use.

Detection of Circulating Tissue Factor and Factor VII in a Normal Population

1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Normal Population ◽  
Mean Value ◽  
Factor Vii ◽  
Significant Difference ◽  
Age Dependent ◽  
The Mean ◽  
Highly Correlated ◽  
And Gender

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.

COLONY OF THE FUNGUS Aspergillus oryzae AND SELF-AFFINE FRACTAL GEOMETRY OF GROWTH FRONTS

Fractals ◽  
1993 ◽  
Vol 01 (01) ◽  
pp. 11-19 ◽  
Author(s):  
SHU MATSUURA ◽  
SASUKE MIYAZIMA
Keyword(s):  
Aspergillus Oryzae ◽  
Environmental Conditions ◽  
Fractal Geometry ◽  
Nutrient Concentration ◽  
Incubation Temperature ◽  
Characteristic Exponent ◽  
Growth Front ◽  
Favorable Condition ◽  
The Self ◽  
The Mean

A variety of colony shapes of the fungus Aspergillus oryzae under varying environmental conditions such as the nutrient concentration, medium stiffness and incubation temperature are obtained, ranging from a homogeneous Eden-like to a ramified DLA-like pattern. The roughness σ(l, h) of the growth front of the band-shaped colony, where h is the mean front height within l of the horizontal range, satisfies the self-affine fractal relation under favorable environmental conditions. In the most favorable condition of our experiments, its characteristic exponent is found to be a little larger than that of the 2-dimensional Eden model.

A note on the subcritical generalized age-dependent branching process

1976 ◽  
Vol 13 (4) ◽  
pp. 798-803 ◽  
Author(s):  
R. A. Doney
Keyword(s):  
Branching Process ◽  
Sufficient Condition ◽  
Necessary And Sufficient Condition ◽  
Malthusian Parameter ◽  
Age Dependent ◽  
The Mean ◽  
Mean Function ◽  
Necessary And Sufficient

For a subcritical Bellman-Harris process for which the Malthusian parameter α exists and the mean function M(t)∼ aeat as t → ∞, a necessary and sufficient condition for e–at (1 –F(s, t)) to have a non-zero limit is known. The corresponding condition is given for the generalized branching process.

Étude du développement hétéroblastique chez quelques espèces du genre Medicago

1983 ◽  
Vol 61 (8) ◽  
pp. 2212-2223 ◽  
Author(s):  
Catherine Damerval
Keyword(s):  
Environmental Conditions ◽  
Mean Value ◽  
Annual Species ◽  
The Mean ◽  
Shape Changes

Seven foliar types were defined for the first leaf in the heteroblastic development of seven annual species of Medicago L. Among the species, M. aculeata and M. murex have a typical foliar form. There is no relation between the first leaf and the succeeding trifoliolate one. The shape changes of the middle foliole of the trifoliolate leaves during the development allowed to establish a foliar sequence whose mean length was used to suggest an evolutive hierarchy among the taxa. Five quantitative variables were analysed on the first and on the sixth leaf for stability according to environmental conditions; the two stable variables (L/l and L/Pl) have a best discriminant value for the first leaf than for the sixth one. However, intraspecific heterogeneity is high in both cases. A relation between the flowering precocity and the mean value of one of the sixth leaf's variables (that is, the ratio of the length to the width of the foliole limb) was demonstrated in four species only. The heteroblastic development not only allows to establish a relation between foliar stage and physiologic age, but it itself constitutes a very good taxonomic and systematic criterium; it allowed to identify the seven species studied.

scholarly journals Biology and parasitic potential of Doryctobracon areolatuson Anastrepha fraterculus larvae

2011 ◽  
Vol 46 (6) ◽  
pp. 669-671 ◽  
Author(s):  
Adrise Medeiros Nunes ◽  
Dori Edson Nava ◽  
Fernanda Appel Müller ◽  
Rafael da Silva Gonçalves ◽  
Mauro Silveira Garcia
Keyword(s):  
Biological Control ◽  
Sex Ratio ◽  
Adult Emergence ◽  
Parasitism Rate ◽  
Anastrepha Fraterculus ◽  
The Mean ◽  
Parasitoid Development

The objective of this work was to study the biology and parasitic potential of Doryctobracon areolatus on larvae of Anastrepha fraterculus. The egg-adult period, the sex ratio, the longevity, the pupal viability, and the parasitism rate of D. areolatus were determined in laboratory, using A. fraterculus as host. The parasitoid development from oviposition to adult emergence required 25.00±1.70 days, the sex ratio was 0.62±0.09, and the mean longevity was 16.36±3.62 days for males and 10.24±1.71 days for females. The mean parasitism rate was 53.50±8.93%, varying from 41.60 to 68.60%, which shows the potential of this parasitoid for biological control of A. fraterculus.

Immunoreactive IGF-II in serum of healthy subjects and patients with growth hormone disturbances and uraemia

1984 ◽  
Vol 107 (2) ◽  
pp. 164-170 ◽  
Author(s):  
Gösta Enberg ◽  
Kerstin Hall
Keyword(s):  
Confidence Limit ◽  
Binding Protein ◽  
Protein S ◽  
Serum Levels ◽  
Cross Reaction ◽  
Diabetic Patients ◽  
Serum Samples ◽  
Igf I ◽  
Age Dependent ◽  
The Mean

Abstract. A radioimmunoassay has been developed for IGF-II, using Sepharose-coupled antibodies. Porcine insulin, human insulin and human proinsulin showed no cross-reaction, whereas the cross-reaction for IGF-I was 10%. To minimize the influence of the binding protein(s), all serum samples were extracted with acid ethanol before assay. The mean serum level of immunoreactive IGF-II and 95% confidence limit in 46 healthy adults were 587 ng/ml and 354–974 ng/ml, respectively. In contrast to the declining levels of IGF-I with increasing age, no such age-dependent decrease was found for IGF-II levels between 20 to 70 years. No difference in IGF-II levels was found between patients with acromegaly and healthy adult controls. In cord serum and serum from adult patients with GH deficiency the levels were significantly lower (P < 0.001) compared to controls. In diabetic patients with uraemia the mean level and 95% confidence limit were 1222 ng/ml and 532–2808 ng/ml, respectively. Thus, significantly increased serum levels of immunoreactive IGF-II have only been found in serum from patients with uraemia. Whether this is due to an increased production of IGF-II, or secondary to other factors such as the binding protein(s), will require further investigation.

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