Superparasitism in Laboratory rearing ofSpalangia cameroni(Hymenoptera: Pteromalidae), a parasitoid of medfly (Diptera: Tephritidae)

2011 ◽  
Vol 102 (1) ◽  
pp. 51-61 ◽  
Author(s):  
J. Tormos ◽  
J. Asís ◽  
B. Sabater-Muñoz ◽  
L. Baños ◽  
S.F. Gayubo ◽  
...  
Keyword(s):  
Biological Control ◽  
Sex Ratio ◽  
High Frequency ◽  
Ceratitis Capitata ◽  
Adult Emergence ◽  
Female Size ◽  
Laboratory Rearing ◽  
Rearing Conditions ◽  
Different Levels

AbstractThe frequency of superparasitism and its effects on the quality of laboratory-rearedSpalangia cameroni(Hymenoptera: Pteromalidae) parasitoids were investigated under laboratory conditions. Numerous variables were measured, such as the number of ‘ovip holes’ per host as a measure of superparasitism. Adult emergence and sex ratio, as well as female size, emergence ability from soil and longevity were also measured. Finally, an assessment was made of fertility and survival of adult parasitoids emerging from the medflyCeratitis capitata(Diptera: Tephritidae) pupae with different levels of superparasitism. A high frequency and prevalence of superparasitism under laboratory rearing conditions was observed. The number of ‘ovip holes’ per host ranged from one to 17, with an average (±SD) of 2.8±3.4. Sex ratios became increasingly female-biased with increasing levels of superparasitism, although overall levels of wasp emergence (male, female) declined. Nevertheless, no relationship was discerned between female size and level of superparasitism. The ‘emergence ability from the soil’ was higher in those parasitoids that emerged from strongly superparasitized hosts, but not related to the type of substrate in which the host pupae were buried. The level of superparasitism did not have a significant effect on the longevity, fertility and survival of female parasitoids. Our results support the hypothesis that superparasitism inS. cameronimight be adaptive, since attributes such as ‘emergence ability from the soil’, longevity, fertility and survival were not affected by the level of superparasitism or the presumably detrimental effects derived from physical combats among conspecific larvae. Our findings are relevant to recommendations for rearingS. cameronifor biological control releases, as well as shedding light on superparasitism under both laboratory and field conditions.

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.

Validation of a methodology for rearingSpalangia cameroni(Hymenoptera: Pteromalidae) onCeratitis capitata(Diptera: Tephritidae)

2014 ◽  
Vol 146 (6) ◽  
pp. 676-683 ◽  
Author(s):  
J. Tormos ◽  
B. Sabater-Muñoz ◽  
J.D. Asís ◽  
F. Beitia
Keyword(s):  
Sex Ratio ◽  
Ceratitis Capitata ◽  
Biocontrol Agent ◽  
Sex Ratios ◽  
Mass Rearing ◽  
Laboratory Rearing ◽  
Pupal Parasitoid ◽  
Mass Rear ◽  
Laboratory Colony ◽  
Potential Biocontrol Agent

AbstractSpalangia cameroniPerkins (Hymenoptera: Pteromalidae) is a pupal parasitoid of the Medfly,Ceratitis capitata(Wiedmann) (Diptera: Tephritidae), one of the principal pests of Spanish agriculture.Spalangia cameroniis a potential biocontrol agent for this pest if methods can be developed to mass-rear it effectively onC. capitata. Here, we report on the use of freeze-killed pupae ofC. capitatato maintain a laboratory colony ofS. cameroni, with a view to setting up a mass-rearing protocol. Realised fecundity, adult progeny, sex ratio, and superparasitism level were the principal parameters analysed. No significant differences were found in respect of these parameters between living or freeze-killed Medfly pupae used as hosts, although sex ratios showed a bias towards females in the case of freeze-killed pupae. Freeze-killed pupae were concluded to present the best option for the laboratory-rearing ofS. cameroni, on account of ease of rearing, and avoidance of the emergence of Medfly adults.

scholarly journals Density of Diachasmimorpha longicaudata (Ashmead) and host Ceratitis capitata (Wied) larvae for the increase of parasitoid female production

2018 ◽  
Vol 85 (0) ◽  
Author(s):  
Carlos Gustavo da Cruz ◽  
Clarice Diniz Alvarenga ◽  
Patricia Cristina do Carmo Oliveira ◽  
Edileuza dos Reis Souza Conceição ◽  
Zenobia Cardoso dos Santos ◽  
...  
Keyword(s):  
Biological Control ◽  
Sex Ratio ◽  
Ceratitis Capitata ◽  
Larval Density ◽  
Mortality Rates ◽  
Female Parasite ◽  
Progeny Production ◽  
Female Progeny ◽  
Diachasmimorpha Longicaudata ◽  
Pupal Mortality

ABSTRACT: The objective of the present study was to evaluate the ratio of Ceratitis capitata larvae/female of Diachasmimorpha longicaudata that results in the increase of parasitism and the production of females in the progeny. We used 8-day-old copulated D. longicaudata females with oviposition parasite experience and third instar larvae of C. capitata from rearing stock maintained at the Laboratory of Biological Control of Universidade Estadual de Montes Claros (Unimontes). Five densities of C. capitata larvae (10, 20, 30, 40, and 50) were offered to parasitoid females that were at five different densities (1, 2, 5, 10, and 15). The larvae were exposed to the parasitoid females by means of “parasitism units” in adapted cages for 1 hour. Sex ratio, percentage of parasitism, and pupal mortality were evaluated. Both host larval density and female parasite density influenced parasitism, female progeny production, and pupal mortality. Higher female production was observed in the progeny in ratios of 1:1 and 2:1 (larvae/females). Ratios above 1:2 reduced the sex ratio, and ratios below 1:1 caused high pupal mortality rates. The females had higher parasitism activity when they were in groups dividing the same space. Equal ratios of Ceratitis capitata larvae and parasitoid females resulted in improved efficiency in progeny females.

The Preimaginal Phases and Development of Pachycrepoideus vindemmiae (Hymenoptera, Pteromalidae) on Mediterranean Fruit Fly, Ceratitis capitata (Diptera, Tephritidae)

2009 ◽  
Vol 15 (5) ◽  
pp. 422-434 ◽  
Author(s):  
José Tormos ◽  
Francisco Beitia ◽  
Elias A. Böckmann ◽  
Josep D. Asís ◽  
Severiano Fernández
Keyword(s):  
Ceratitis Capitata ◽  
Adult Emergence ◽  
Fruit Fly ◽  
Instar Larva ◽  
Developmental Time ◽  
Laboratory Rearing ◽  
Mature Larva ◽  
Larval Instars ◽  
Microscopic Techniques ◽  
Scanning Electron

AbstractThe development and morphology of the immature phases of Pachycrepoideus vindemmiae (Rondani, 1875) (Hymenoptera, Pteromalidae) are described from a laboratory rearing culture maintained on Ceratitis capitata (Wiedemann, 1824) (Diptera, Tephritidae) using microscopic techniques, including light and scanning electron microscopy. The surface of the chorion of the egg is granulated, and the micropyle occurs at the anterior end. The labrum of the first instar larva does not have sensilla, and the second to fourth instar larvae have setae on the head. The mature larva is characterized by the position and number of the integumental differentations (sensilla and setae). On completion of larval development, an adecticous and exarate pupa is produced. As for the adult, the mandibles of the pupae are toothed. Five larval instars are recorded, based on statistical analyses of the sizes of the larval mandibles in combination with characters such as the number of exuviae and excretion of the meconium. Developmental time from egg to adult emergence was ∼18–20 days for males and ∼21–23 days for females at 21–26°C, 55–85 relative humidity, and a 16L:8D photoperiod. The results show that the eggs and different larval instars of this parasitoid can be unambiguously identified only by scanning electron microscope.

Simulation of vibration piercing of pipe blank at press

2020 ◽  
Vol 76 (11) ◽  
pp. 1128-1138
Author(s):  
S. R. Rakhmanov
Keyword(s):  
High Frequency ◽  
Deformation Zone ◽  
Pipe Blank ◽  
Equipment Operation ◽  
Metal Deformation ◽  
Technological Tool ◽  
High Frequency Vibrations ◽  
Pipe Blanks ◽  
Wave Phenomena

In some cases, the processes of piercing or expanding pipe blanks involve the use of high-frequency active vibrations. However, due to insufficient knowledge, these processes are not widely used in the practice of seamless pipes production. In particular, the problems of increasing the efficiency of the processes of piercing or expanding a pipe blank at a piercing press using high-frequency vibrations are being solved without proper research and, as a rule, by experiments. The elaboration of modern technological processes for the production of seamless pipes using high-frequency vibrations is directly related to the choice of rational modes of metal deformation and the prediction resistance indicators of technological tools and the reliability of equipment operation. The creation of a mathematical model of the process of vibrating piercing (expansion) of an axisymmetric pipe blank at a piercing press of a pipe press facility is an actual task. A calculation scheme for the process of piercing a pipe plank has been elaborated. A dependence was obtained characterizing the speed of front of plastic deformation propagation on the speed of penetration of a vibrated axisymmetric mandrel into the pipe workpiece being pierced. The dynamic characteristics of the occurrence of wave phenomena in the metal being pierced under the influence of a vibrated tool have been determined, which significantly complements the previously known ideas about the stress-strain state of the metal in the deformation zone. The deformation fields in the zones of the disturbed region of the deformation zone were established, taking into account the high-frequency vibrations of the technological tool. It has been established that the choice of rational parameters (amplitude-frequency characteristics) of the vibration piercing process of a pipe blank results in significant increase in the efficiency of the process, the durability of the technological tool and the quality of the pierced blanks.

Dynamics of the processes in metal machining

1998 ◽  
Vol 2 ◽  
pp. 115-122
Author(s):  
Donatas Švitra ◽  
Jolanta Janutėnienė
Keyword(s):  
High Frequency ◽  
Machine Tools ◽  
Metal Cutting ◽  
Cutting Tool ◽  
Low Frequency ◽  
Metal Cutting Machine ◽  
Cutting Machine ◽  
Metal Machining

In the practice of processing of metals by cutting it is necessary to overcome the vibration of the cutting tool, the processed detail and units of the machine tool. These vibrations in many cases are an obstacle to increase the productivity and quality of treatment of details on metal-cutting machine tools. Vibration at cutting of metals is a very diverse phenomenon due to both it’s nature and the form of oscillatory motion. The most general classification of vibrations at cutting is a division them into forced vibration and autovibrations. The most difficult to remove and poorly investigated are the autovibrations, i.e. vibrations arising at the absence of external periodic forces. The autovibrations, stipulated by the process of cutting on metalcutting machine are of two types: the low-frequency autovibrations and high-frequency autovibrations. When the low-frequency autovibration there appear, the cutting process ought to be terminated and the cause of the vibrations eliminated. Otherwise, there is a danger of a break of both machine and tool. In the case of high-frequency vibration the machine operates apparently quiently, but the processed surface feature small-sized roughness. The frequency of autovibrations can reach 5000 Hz and more.

Systematic literature review of clinical outcomes in adults with metastatic or advanced synovial sarcoma

2020 ◽  
Vol 16 (35) ◽  
pp. 2997-3013
Author(s):  
Kentaro Kogushi ◽  
Michael LoPresti ◽  
Shunya Ikeda
Keyword(s):  
Synovial Sarcoma ◽  
High Frequency ◽  
Clinical Evidence ◽  
Systemic Treatment ◽  
Progression Free Survival ◽  
Treatment Modalities ◽  
Free Survival ◽  
New Treatment ◽  
Poor Outcomes

Background: Synovial sarcoma (SS) is a rare, aggressive soft tissue sarcoma with a poor prognosis after metastasis. The objective of this study was to conduct a systematic review of the clinical evidence for therapeutic options for adults with metastatic or advanced SS. Materials & methods: Relevant databases were searched with predefined keywords. Results: Thirty-nine publications reported clinical data for systemic treatment and other interventions. Data on survival outcomes varied but were generally poor (progression-free survival: 1.0–7.7 months; overall survival: 6.7–29.2 months) for adults with metastatic and advanced SS. A high frequency of neutropenia with systemic treatment and low quality of life post-progression were reported. Conclusion: Reported evidence suggests poor outcomes in adults with metastatic and advanced SS and the need for the development of new treatment modalities.

Effectiveness of Entomopathogenic Nematodes Against Ceratitis capitata (Diptera: Tephritidae) Pupae and Nematode Compatibility with Chemical Insecticides

2021 ◽  
Author(s):  
Maguintontz Cedney Jean-Baptiste ◽  
Andressa Lima de Brida ◽  
Daniel Bernardi ◽  
Sérgio da Costa Dias ◽  
Juliano de Bastos Pazini ◽  
...  
Keyword(s):  
Biological Control ◽  
Entomopathogenic Nematodes ◽  
Ceratitis Capitata ◽  
Integrated Management ◽  
Fruit Fly ◽  
Steinernema Carpocapsae ◽  
Mediterranean Fruit Fly ◽  
Fruit Crops ◽  
Class 1 ◽  
Pupal Mortality

Abstract The Mediterranean fruit fly Ceratitis capitata (Wiedemann, 1824) (Diptera: Tephritidae) is among the main pests of fruit crops worldwide. Biological control using entomopathogenic nematodes (EPNs) may be an alternative to suppress populations of this pest. Thus, the aim of this study was to evaluate the pathogenicity and virulence of six EPN isolates (Heterorhabditis bacteriophora HB, H. amazonensis IBCB-n24, Steinernema carpocapsae IBCB-n02, S. rarum PAM-25, S. glaseri IBCB-n47, and S. brazilense IBCB-n06) against C. capitata pupae. The compatibility of EPNs with different chemical insecticides that are registered for management of C. capitata was also assessed. Isolates of H. bacteriophora HB and S. brazilense IBCB-n06 at a concentration of 1,000 infective juveniles (IJ)/ml proved to be most pathogenic to C. capitata (70 and 80% mortality, respectively). In contrast, the isolates H. amazonensis IBCB-n24, Steinernema carpocapsae IBCB-n02, S. rarum PAM-25, S. glaseri IBCB-n47 provided pupal mortality of less than 60%. Bioassays to determine lethal concentrations indicated that concentrations of 600 IJ/ml (H. bacteriophora HB) and 1,000 IJ/ml (S. brazilense IBCB-n06) showed the highest virulence against C. capitata pupae. In contrast, the highest numbers of IJs emerged at concentrations of 1,200 and 200 IJ/ml. In compatibility bioassays, malathion, spinetoram, phosmet, acetamiprid, and novaluron were considered compatible with and harmless (Class 1) to H. bacteriophora HB and S. brazilense IBCB-n06, according to IOBC/WPRS. This information is important for implementing integrated management programs for C. capitata, using biological control with EPNs, whether alone or in combination with chemical insecticides.

scholarly journals How Good Is the STW Sensor? An Account from a Larger Shipping Company

2021 ◽  
Vol 9 (5) ◽  
pp. 465
Author(s):  
Angelos Ikonomakis ◽  
Ulrik Dam Nielsen ◽  
Klaus Kähler Holst ◽  
Jesper Dietz ◽  
Roberto Galeazzi
Keyword(s):  
High Frequency ◽  
Additional Data ◽  
Empirical Method ◽  
Influential Factor ◽  
Sensor Data ◽  
Sea State ◽  
Shipping Company ◽  
Frequency Sensor ◽  
Semi Empirical

This paper examines the statistical properties and the quality of the speed through water (STW) measurement based on data extracted from almost 200 container ships of Maersk Line’s fleet for 3 years of operation. The analysis uses high-frequency sensor data along with additional data sources derived from external providers. The interest of the study has its background in the accuracy of STW measurement as the most important parameter in the assessment of a ship’s performance analysis. The paper contains a thorough analysis of the measurements assumed to be related with the STW error, along with a descriptive decomposition of the main variables by sea region including sea state, vessel class, vessel IMO number and manufacturer of the speed-log installed in each ship. The paper suggests a semi-empirical method using a threshold to identify potential error in a ship’s STW measurement. The study revealed that the sea region is the most influential factor for the STW accuracy and that 26% of the ships of the dataset’s fleet warrant further investigation.

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