AGE-SPECIFIC PATTERN OF HOST DISCRIMINATION BY THE APHID PARASITOID EPHEDRUS CALIFORNICUS BAKER (HYMENOPTERA: APHIDIIDAE)

1990 ◽  
Vol 122 (2) ◽  
pp. 349-361 ◽  
Author(s):  
W. Völkl ◽  
M. Mackauer
Keyword(s):  
Acyrthosiphon Pisum ◽  
Specific Pattern ◽  
Search Rate ◽  
Host Discrimination ◽  
Aphid Parasitoid ◽  
Conspecific Female ◽  
Egg Deposition ◽  
Age Dependent ◽  
Hymenopteran Parasitoids

AbstractThe solitary aphid parasitoid Ephedrus californicus Baker is able to discriminate between unparasitized and parasitized third-instar nymphs of the pea aphid, Acyrthosiphon pisum (Harris). Superparasitism varied with the number of mature eggs (which is age-dependent) present in the ovaries as well as with the number and the quality of any hosts encountered. Conspecific superparasitism varied with wasp age; older females, with a large egg supply, accepted hosts parasitized by a conspecific female if unparasitized aphids were unavailable. Self superparasitism occurred at all ages; it was the least likely behaviour compared with egg deposition in unparasitized and conspecific-parasitized hosts. Prior experience (learning) was not necessary for host discrimination, but it did influence the search rate, which was higher in inexperienced than experienced females. In choice experiments, wasps preferred conspecific- over self-parasitized aphids and thus were able to distinguish between them. It is suggested that oviposition markers vary among conspecific females. The data are discussed with reference to theories about oviposition decisions and progeny allocation in solitary hymenopteran parasitoids.

CONSPECIFIC SUPERPARASITISM IN TWO PARASITOID WASPS, APHIDIUS ERVI HALIDAY AND APHELINUS ASYCHIS WALKER: REPRODUCTIVE STRATEGIES INFLUENCE HOST DISCRIMINATION

1991 ◽  
Vol 123 (6) ◽  
pp. 1229-1237 ◽  
Author(s):  
B. Bai
Keyword(s):  
Reproductive Strategies ◽  
Acyrthosiphon Pisum ◽  
Aphidius Ervi ◽  
Parasitoid Wasps ◽  
Host Discrimination ◽  
Larval Competition ◽  
Parasitoid Species ◽  
Aphid Parasitoid ◽  
Aphelinus Asychis ◽  
Physiological Suppression

AbstractConspecific host discrimination and larval competition in two aphid parasitoid species were studied in the laboratory using the pea aphid, Acyrthosiphon pisum (Harris) (Homoptera: Aphididae), as a host. Aphidius ervi Haliday (Hymenoptera: Aphidiidae) used internal host cues to discriminate between unparasitized and conspecific parasitized hosts. When only parasitized hosts were available, females oviposited into recently parasitized ones where their progeny had a good chance to survive, but rejected those parasitized ≥24 h earlier where their offspring normally died. Competitions occurred only after both eggs had hatched. Larvae eliminated supernumeraries by means of physical combat and physiological suppression. In Aphelinus asychis Walker (Hymenoptera: Aphelinidae), factors, or changes in host internal condition, associated with hatching of the first egg resulted in suppression of conspecific competitors which could be in either larval or egg stage. The older larvae always won competitions through physiological means. A wasp’s oviposition decision is shown to be influenced by the probability of its progeny’s survival. Species that have different reproductive strategies may respond differently to identical host conditions.

HOST DISCRIMINATION BY THE APHID PARASITOID APHELINUS ASYCHIS (HYMENOPTERA: APHELINIDAE): WHEN SUPERPARASITISM IS NOT ADAPTIVE

1990 ◽  
Vol 122 (2) ◽  
pp. 363-372 ◽  
Author(s):  
B. Bai ◽  
M. Mackauer
Keyword(s):  
Egg Production ◽  
Acyrthosiphon Pisum ◽  
Host Acceptance ◽  
Parasitoid Species ◽  
Aphid Parasitoid ◽  
Egg Deposition ◽  
Aphelinus Asychis ◽  
Solitary Parasitoid ◽  
Long Time ◽  
Host Rejection

AbstractFemales of the solitary parasitoid Aphelinus asychis Walker discriminated between unparasitized and parasitized second-instar nymphs of the pea aphid, Acyrthosiphon pisum (Harris). Wasps normally avoided superparasitism, except when they were confined with few hosts for a long time. Parasitoid females did not need previous experience with unparasitized aphids (learning) in order to discriminate. They probed with the ovipositor any aphids encountered, a behaviour suggesting that host acceptance and rejection were determined by internal cues. Prolonged ovipositor insertion (>80 s) was correlated with host acceptance and egg deposition, but short insertion times (≤80 s) generally indicated host rejection. Females tended to reject both self- and conspecific-parasitized aphids when provided with two of each kind. We consider hypotheses mat conspecific superparasitism may be adaptive and give examples to show exceptions. We propose that, in egg-limited parasitoid species such as A. asychis, a reproductive strategy based on the regulation of egg production and on oosorption can explain the equal avoidance of self and conspecific superparasitism.

DISCRIMINATION BETWEEN SELF- AND CONSPECIFIC-PARASITIZED HOSTS IN THE APHID PARASITOID PRAON PEQUODORUM VIERECK (HYMENOPTERA: APHIDIIDAE)

1993 ◽  
Vol 125 (5) ◽  
pp. 957-964 ◽  
Author(s):  
T.P. Danyk ◽  
M. Mackauer
Keyword(s):  
Conditional Probability ◽  
Acyrthosiphon Pisum ◽  
Pea Aphid ◽  
Host Quality ◽  
Host Discrimination ◽  
Aphid Parasitoid ◽  
Type Host ◽  
Host Type ◽  
Solitary Parasitoid ◽  
Preference Tests

AbstractWe evaluated host discrimination and oviposition restraint in the wasp Praon pequodorum Viereck, a solitary parasitoid of the pea aphid, Acyrthosiphon pisum (Harris). In dichotomous preference tests, wasps attacked more unparasitized than equally available parasitized aphids, and more self-parasitized aphids than aphids parasitized by conspecific females. The conditional probability of a female laying an egg into an attacked aphid was independent of the host type. Host discrimination apparently involves a volatile and individual-specific pheromone marker. Females expecting to compete with other (conspecific) wasps for a limited host supply may ensure possession of the host by self superparasitism. Because host examination requires considerably more time than oviposition in P. pequodorum (and eggs contain few resources), it may be adaptive for a female to lay an egg in an examined host regardless of variations in host quality.

CHARACTERISTICS OF AGE-DEPENDENT CHANGES IN THE URINE'S PROTEOM COMPOSITION OF THE HEALTHY PERSONS (EXPERIMENTAL AND THEORETICAL STUDY)

2020 ◽  
pp. 735-740
Author(s):  
Л. Х. Пастушкова ◽  
Д. Н. Каширина ◽  
А. Г. Гончарова ◽  
Н. Б. Захарова ◽  
Е. С. Тийс ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Insulin Signaling ◽  
Defense Mechanisms ◽  
Theoretical Study ◽  
Clinical Manifestations ◽  
Age Dependent ◽  
First Time ◽  
Healthy Persons ◽  
Over Time

Впервые описаны белки, достоверно увеличивающиеся и уменьшающиеся в моче с возрастом в интервале 20-60 лет. Охарактеризованы комбинации белков, связанных с изменением иммунных процессов, нарушением реологии крови, в том числе риском коагулопатии, противоопухолевых защитных механизмов, инсулинового сигнального пути, с изменением характеристик клеточного деления и качества новообразованной ткани. Таким образом, возрастная динамика основных процессов запускает каскад реакций, проявляющихся в замыкании «патологических биохимических кругов», которые формируют предпосылки к развитию заболеваний и, с течением времени, клинические проявления. For the first time proteins are described, reliably increasing and decreasing in urine with age in the range of 20 to 60 years. The combinations of proteins associated with changes in immune processes, violation of blood reology, including the risk of coagulopathy, anticancer defense mechanisms, insulin signaling pathway, changes in cell characteristics are characterized division and quality of the newly formed fabric. Thus, the age dynamics of the main processes triggers a cascade of reactions manifested in the closure of «pathological biochemical circles» that form the prerequisites for the development of diseases and, over time, clinical manifestations.

scholarly journals Family business, director compensation and board efficacy: the case of Taiwan

2013 ◽  
Vol 11 (1) ◽  
pp. 81-91
Author(s):  
Tsun-Jui Hsieh ◽  
Yu-Ju Chen
Keyword(s):  
Firm Performance ◽  
Family Business ◽  
Positive Impact ◽  
Specific Pattern ◽  
Chinese Family ◽  
Outside Directors ◽  
Director Compensation ◽  
Outside Director ◽  
The Impact

This paper investigates the impact of outside directors on firm performance during legal transitions and examines how the roles of family business and director compensation influence board efficacy. By using Taiwanese listed companies as our sample, the empirical results show that outside directors who are appointed by legal mandate have less positive impacts on firm performance than outside directors appointed voluntarily. Family business weakens the positive impact of outside director on firm performance. The evidence further suggests that director compensation contributes to firm performance, particularly when outside directors are voluntarily appointed. The findings provide western managers with an understanding of how the typical Chinese family business affects board independence. We also demonstrate and incorporate the cultural and the ownership characteristics into the analysis to present a country-specific pattern that should be informative for foreign investors who are concerned about the quality of corporate governance in East Asia.

scholarly journals Age - related behaviour on individually caged rabbits

2017 ◽  
Vol 62 (1) ◽  
pp. 21 ◽  
Author(s):  
A. KATSAROU (Α. ΚΑΤΣΑΡΟΥ) ◽  
A. TSIRONI (Α. ΤΣΙΡΩΝΗ) ◽  
M. SERAFETINIDOU (Μ. ΣΕΡΑΦΕΤΙΝΙΔΟΥ) ◽  
C. VOYAZAKI (Χ. ΒΟΓΙΑΤΖΑΚΗ) ◽  
V. BAUMANS ◽  
...  
Keyword(s):  
Age Differences ◽  
Environmental Enrichment ◽  
Housing Conditions ◽  
Enrichment Programs ◽  
Video Recordings ◽  
Age Related ◽  
Age Dependent ◽  
Enrichment Program ◽  
Group A

Housing conditions and environmental enrichment of individually caged laboratory rabbits is of great importance for the welfare of the animals and the quality of the experimental results. In order to improve the design of existing environmental enrichment programs for laboratory rabbits, considerable knowledge of the behavioural needs of this species is necessary. Taking this into consideration, the aim of this study was to monitor and analyze the behaviour of juvenile and young adult rabbits in order to establish whether there are any age-dependent differences in grooming, rearing, sniffing, eating, drinking and gnawing. 12 NZW rabbits were divided into two groups: group A consisted of six 6-month-old rabbits (young adults) and group Β consisted of six 2-month-old rabbits (juvenile). All animals were already housed for more than twenty days under the same conditions in the animal facility. Both groups of rabbits were video-recorded between 06:00h - 18:00h for four consecutive days. The frequency of each behaviour was determined and compared in the two groups of rabbits from the video recordings. The frequencies of grooming, eating and gnawing in the young rabbits were significantly greater than those in the older rabbits (p<0.05). No statistical differences were found between the two groups for rearing, sniffing and drinking. From these results, we concluded that even small age differences should be taken into account when designing an environmental enrichment program for individually caged rabbits.

EFFECT OF THE PEA APHID, ACYRTHOSIPHON PISUM (HEMIPTERA (HOMOPTERA): APHIDIDAE), ON YIELD AND QUALITY OF FORAGE ALFALFA

1982 ◽  
Vol 114 (6) ◽  
pp. 485-489 ◽  
Author(s):  
A. M. Harper ◽  
M. S. Kaldy
Keyword(s):  
Dry Matter ◽  
Acyrthosiphon Pisum ◽  
Dry Weight ◽  
Pea Aphid ◽  
Yield And Quality ◽  
Nitrogen Free Extract ◽  
Calcium Magnesium ◽  
The Mean ◽  
Limited Change

AbstractThe pea aphid, Acyrthosiphon pisum (Harris), affected yield by significantly reducing the mean height of aphid-susceptible Grimm alfalfa in a greenhouse experiment by 45%, the height of the longest stem by 35%, the green weight by 38%, the dry weight by 44%, and the fiber by 13%. There was limited change in quality of alfalfa. The percentages of protein, fat, total sugar, reducing sugar, dry matter, and nitrogen-free extract were not significantly different in the infested and non-infested alfalfa. Potassium was significantly lower in the infested plants but they contained more calcium, magnesium, and phosphorus. With the exception of isoleucine the amino acid composition was similar in the infested and non-infested alfalfa.

Parent perceived quality of life is age‐dependent in children with food allergy

2012 ◽  
Vol 23 (5) ◽  
pp. 412-419 ◽  
Author(s):  
Jacqueline Wassenberg ◽  
Marie‐Madeleine Cochard ◽  
Audrey DunnGalvin ◽  
Pierluigi Ballabeni ◽  
Bertine M. J. Flokstra‐de Blok ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Food Allergy ◽  
Perceived Quality ◽  
Perceived Quality Of Life ◽  
Age Dependent
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