WorldWideScience

Sample records for mass-reared sterile mediterranean

  1. Mass-rearing for sterile insect release

    International Nuclear Information System (INIS)

    Parker, A.G.

    2005-01-01

    As the sterile insect technique (SIT) relies upon released sterile male insects efficiently competing with wild males to mate with wild females, it follows that mass-rearing of insects is one of the principal steps in the process. Mass-rearing for the SIT presents both problems and opportunities due to the increased scale involved compared with rearing insects for most other purposes. This chapter discusses facility design, environmental concerns, strain management, quality control, automation, diet, sex separation, marking, and storage in relation to rearing for the SIT. (author)

  2. Manipulation of the microbiota of mass-reared Mediterranean fruit flies Ceratitis capitata (Diptera: Tephritidae) improves sterile male sexual performance.

    Science.gov (United States)

    Ben Ami, Eyal; Yuval, Boaz; Jurkevitch, Edouard

    2010-01-01

    The sterile insect technique (SIT) is a method of biological control whereby millions of factory reared sterile male insects are released into the field. This technique is commonly used to combat the Mediterranean fruit fly (Ceratitis capitata, Diptera: Tephritidae). Sterile medfly males are less competent in attracting and mating with wild females, a property commonly linked to the irradiation process responsible for the sterilization. As bacteria are important partners in the fly's life cycle, we used molecular analytical methods to study the community structure of the gut microbiota in irradiated male medflies. We find that the sterilizing irradiation procedure affects the gut bacterial community structure of the Mediterranean fruit fly. Although the Enterobacteriaceae family remains the dominant bacterial group present in the gut, the levels of Klebsiella species decreases significantly in the days after sterilization. In addition, we detected substantial differences in some bacterial species between the mass rearing strain Vienna 8 and the wild strain. Most notable among these are the increased levels of the potentially pathogenic species Pseudomonas in the industrial strain. Testing the hypothesis that regenerating the original microbiota community could result in enhanced competitiveness of the sterile flies, we found that the addition of the bacterial species Klebsiella oxytoca to the postirradiation diet enables colonization of these bacteria in the gut while resulting in decreased levels of the Pseudomonas sp. Feeding on diets containing bacteria significantly improved sterile male performance in copulatory tests. Further studies will determine the feasibility of bacterial amelioration in SIT operations.

  3. Mating-induced changes in olfactory-mediated behavior of laboratory-reared normal, sterile, and wild female Mediterranean fruit flies (Diptera: Tephritidae) mated to conspecific males

    International Nuclear Information System (INIS)

    Jang, E.B.; McInnis, D.O.; Lance, D.R.; Carvalho, L.A.

    1998-01-01

    Laboratory-reared normal, sterile, and wild female Mediterranean fruit flies, Ceratitis capitata (Wiedemann), were mated with laboratory-reared normal, sterile, and wild male flies to assess the ability of males to alter olfactory-mediated behavioral responses of females to male-produced pheromone or host fruit odor. Virgin females of all 3 types showed a preferential attraction and arrestment on yellow spheres emitting male-produced pheromone in a laboratory flight tunnel. Laboratory-reared normal and wild females mated to laboratory reared normal, sterile, or wild males switched their behavior showing strong preferential attraction to, arrestment on, and egg-laying in (for laboratory-reared females) yellow spheres emitting host fruit odor (guava) over male-produced pheromone. Sterile females did not show a significant switch in behavior except when mated to sterile males. The olfactory-mediated behavioral switch was most evident in the laboratory-reared normal female × laboratory-reared normal male mating. These findings suggest that irradiation of males inducing gamete sterility does not affect the factor(s) from the male accessory gland associated with altering female olfactory behavior. The ability of sterile males to alter adequately olfactory-mediated behavior of wild females is discussed in the context of the sterile insect technique for control of Mediterranean fruit flies in the field

  4. Quality control method to measure predator evasion in wild and mass-reared Mediterranean fruit flies (Diptera: Tephritidae)

    International Nuclear Information System (INIS)

    Hendrichs, M.; Wornoayporn, V.; Hendrichs, J.; Katsoyannos, B.

    2007-01-01

    Sterile male insects, mass-reared and released as part of sterile insect technique (SIT) programs, must survive long enough in the field to mature sexually and compete effectively with wild males for wild females. An often reported problem in Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) SIT programs is that numbers of released sterile males decrease rapidly in the field for various reasons, including losses to different types of predators. This is a serious issue in view that most operational programs release sterile flies at an age when they are still immature. Previous field and field-cage tests have confirmed that flies of laboratory strains are less able to evade predators than wild flies. Such tests involve, however, considerable manipulation and observation of predators and are therefore not suitable for routine measurements of predator evasion. Here we describe a simple quality control method with aspirators to measure agility in medflies and show that this parameter is related to the capacity of flies to evade predators. Although further standardization of the test is necessary to allow more accurate inter-strain comparisons, results confirm the relevance of measuring predator evasion in mass-reared medfly strains. Besides being a measure of this sterile male quality parameter, the described method could be used for the systematic selection of strains with a higher capacity for predator evasion. (author) [es

  5. A filter rearing system for mass reared genetic sexing strains of Mediterranean fruit fly (Diptera: Tephritidae)

    International Nuclear Information System (INIS)

    Fisher, Kingsley; Caceres, Carlos

    2000-01-01

    The Mediterranean fruit fly (Medfly), Ceratitis capitata (Wied.), is arguably the world's most widespread pest of fresh fruit production. With mounting controversy over using chemicals against insect pests, the sterile insect technique (SIT) has become increasingly more important as a successful technology in controlling or eradicating many insect pests. However, the wider adoption of SIT for Medflies has been hindered by damage to fruit from sterile female stings (Hendrichs et al. 1995). Moreover, the release of sterile females in SIT for Medflies is not efficacious (Hendrichs et al. 1995), a point validated in the field in Hawaii (McInnis et al. 1994) and Guatemala (Rendon, personal communication). Hendrichs et al. (1995) list many other advantages for releasing only male Medflies including improved economy, increased safety and improved field monitoring. Genetic systems for the separation of sexes have been developed for Medflies (Franz and Kerremans 1994, Willhoeft et al. 1996) and they allow for large-scale releases of only males. Genetic sexing strains (GSS), as they are known, are based upon selectable characters linked to the male sex by using a Y-autosome translocation (Franz et al. 1996). There are two types of GSS used in mass rearing. First, strains based upon a recessive mutation (wp) change the pupal colour from brown to white. In these strains, females emerge from white pupae and males from brown pupae. A machine is used to sort the pupae based upon colour. First described by Robinson and Van Heemert (1982), the most recent strain, SEIB 6-96 based upon the T(Y;5) 2-22 translocation, is relatively stable in small scale rearing (Franz et al. 1994). Second are the temperature sensitive lethal strains (wp/tsl) which carry a temperature sensitive lethal (tsl) mutation in addition to wp. In tsl strains, female embryos are killed by exposing eggs to a 3 C temperature during development (Franz et al. 1996). Male embryos are not temperature sensitive and

  6. Sexual performance of mass reared and wild Mediterranean fruit flies (Diptera: Tephritidae) from various origins of the Madeira Islands

    International Nuclear Information System (INIS)

    Pereira, R.; Silva, N.; Quintal, C.; Abreu, R.; Andrade, J.; Dantas, L.

    2007-01-01

    The success of Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) control programs integrating the sterile insect technique (SIT) is based on the capacity of released the sterile males to compete in the field for mates. The Islands of Madeira are composed of 2 populated islands (Madeira and Porto Santo) where the medfly is present. To evaluate the compatibility and sexual performance of sterile flies we conducted a series of field cage tests. At same time, the process of laboratory domestication was evaluated. 3 wild populations, one semi-wild strain, and 1 mass reared strain were evaluated: the wild populations of (1) Madeira Island (north coast), (2) Madeira Island (south coast), and (3) Porto Santo Island; (4) the semi-wild population after 7 to 10 generations of domestication in the laboratory (respectively, for first and second experiment); and (5) the genetic sexing strain in use at Madeira medfly facility (VIENNA 7mix2000). Field cage experiments showed that populations of all origins are mostly compatible. There were no significant differences among wild populations in sexual competitiveness. Semi-wild and mass-reared males performed significantly poorer in both experiments than wild males in achieving matings with wild females. The study indicates that there is no significant isolation among strains tested, although mating performance is reduced in mass-reared and semi-wild flies after 7 to 10 generations in the laboratory. (author) [es

  7. Improving mating performance of mass-reared sterile Mediterranean fruit flies (Diptera: Tephritidae) through changes in adult holding conditions: demography and mating competitiveness

    International Nuclear Information System (INIS)

    Liedo, P.; Salgado, S.; Oropeza, A.; Toledo, J.

    2007-01-01

    Mass rearing conditions affect the mating behavior of Mediterranean fruit flies (medflies) Ceratitis capitata (Wiedemann). We evaluated the effect of slight changes in the adult holding conditions of adult flies maintained for egg production on their mating performance. Colonization was initiated from wild flies collected as larvae from infested coffee berries (Coffea arabica L.). When pupae were close to adult emergence, they were randomly divided into 3 groups and the emerging adults were reared under the following conditions: (1) Metapa System (MS, control), consisting of 70 x 45 x 15 cm aluminum frame, mesh covered cages, with a density of 2,200 flies per cage and a 1:1 initial sex ratio; (2) Insert System (IS), with the same type of cage, and the same fly density and sex ratio as in the MS treatment, but containing twelve Plexiglas pieces (23 x 8.5 cm) to provide additional horizontal surface areas inside the cage; and (3) Sex-ratio System (SS), same as IS, but in this case the initial male: female ratio was 4:1. Three d later, newly emerged females were introduced, so the ratio became 3:1 and on the 6th d another group of newly emerged females was added to provide a 2:1 final sex ratio, at which the final density reached 1,675 flies per cage. The eggs collected from each of the 3 treatments were reared independently following standard procedures and the adults were held under the same experimental conditions. This process was repeated for over 10 to 13 generations (1 year). The experiment was repeated 3 times in 3 consecutive years, starting each replicate with a new collection of wild flies. Life tables were constructed for each treatment at the parental, 3rd, 6th, and 9th generations. Standard quality control parameters (pupation at 24 h, pupal weight, adult emergence, and flight ability), were estimated for each treatment every third generation in the third year. For the last generation each year, mating competitiveness was evaluated in field cage tests

  8. Sterile insect technique: a field evaluation of the quality of mass-reared fruit flies

    International Nuclear Information System (INIS)

    1985-01-01

    To optimize the use of the sterile insect technique it is essential to establish precise programmes for the evaluation of mass-reared flies in comparison with the natural population. This video presents a programme carried out at the island of Prosida which represents an extremely favourable habitat for the development of the flies; the flies are a new strain mass-reared in the IAEA's Laboratory at Seibersdorf, Austria. The technique employed is the Marked Release Recapture Technique, which consists of colouring a predetermined number of flies with fluorescent powder before they are released, and then recapturing them. This method provides valuable data about the flies' adaptability, orientation to the habitat, motility, sexual activity and reproduction

  9. Sterile insect technique: a field evaluation of the quality of mass-reared fruit flies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1986-12-31

    To optimize the use of the sterile insect technique it is essential to establish precise programmes for the evaluation of mass-reared flies in comparison with the natural population. This video presents a programme carried out at the island of Prosida which represents an extremely favourable habitat for the development of the flies; the flies are a new strain mass-reared in the IAEA`s Laboratory at Seibersdorf, Austria. The technique employed is the Marked Release Recapture Technique, which consists of colouring a predetermined number of flies with fluorescent powder before they are released, and then recapturing them. This method provides valuable data about the flies` adaptability, orientation to the habitat, motility, sexual activity and reproduction

  10. The sterile-male technique for control of the Mediterranean fruit fly, Ceratitis capitata Wied., in the Mediterranean basin

    International Nuclear Information System (INIS)

    Serghiou, C.

    1975-01-01

    Certain problems caused by the use of insecticides in the management of agricultural pests, such as environmental pollution, insecticide resistance and disturbance of biological balance, has led to the development of selective pest control methods. A prominent place among these for the control of the Mediterranean fruit fly has been attained by the species specific sterile-insect technique (SIT). This study reviews the status of field programmes in countries of the Mediterranean basin, and of related mass rearing, irradiation and field release methodology. The SIT has been successfully tested in Spain, Italy, Israel and Cyprus. In all these cases, however, tests were conducted in small semi-isolated areas where at best a high degree of suppression but not eradication of the fly could be obtained since immigration of gravid females was always possible. The SIT programme in Cyprus and data on medfly ecology in the island is here reviewed in more detail. A proposal is make for the eradication of medfly from Cyprus by the use of an integration of methods, namely bait spraying, cultural practices and sterile-insect releases. (author)

  11. Product quality control, irradiation and shipping procedures for mass-reared tephritid fruit flies for sterile insect release programmes

    International Nuclear Information System (INIS)

    1999-05-01

    This document represents the recommendations, reached by consensus of an international group of quality control experts, on the standard procedures for product quality control (QC) for mass reared tephritid flies that are to be used in Sterile Insect Technique (SIT) programs. In addition, the manual describes recommended methods of handling and packaging pupae during irradiation and shipment. Most of the procedures were designed specifically for use with Mediterranean fruit flies, Ceratitis capitata (Wied.), but they are applicable, with minor modification in some cases, for other tephritid species such as Caribbean fruit fly Anastrepha suspense, Mexican fruit fly A. ludens, and various Bactrocera species. The manual is evolving and subject to periodic updates. The future additions will include other fruit flies as the need is identified. If followed, procedures described in this manual will help ensure that the quality of mass-produced flies is measured accurately in a standardised fashion, allowing comparisons of quality over time and across rearing facilities and field programmes. Problems in rearing, irradiation and handling procedures, and strain quality can be identified and hopefully corrected before control programmes are affected. Tests and procedures described in this document are only part of a total quality control programme for tephritid fly production. The product QC evaluations included in this manual are, unless otherwise noted, required to be conducted during SIT programmes by the Field programme staff not the production staff. Additional product QC tests have been developed and their use is optional (see ancillary test section). Production and process QC evaluations (e.g., analysis of diet components, monitoring the rearing environment, yield of larvae, development rate, etc.) are not within the scope of this document. Quality specifications are included for minimum and mean acceptability of conventional strains of C. capitata, A. ludens, and A

  12. The FAO/IAEA interactive spreadsheet for design and operation of insect mass rearing facilities

    International Nuclear Information System (INIS)

    Caceres, Carlos; Rendon, Pedro

    2006-01-01

    An electronic spreadsheet is described which helps users to design, equip and operate facilities for the mass rearing of insects for use in insect pest control programmes integrating the sterile insect technique. The spreadsheet was designed based on experience accumulated in the mass rearing of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), using genetic sexing strains based on a temperature sensitive lethal (tsl) mutation. The spreadsheet takes into account the biological, production, and quality control parameters of the species to be mass reared, as well as the diets and equipment required. All this information is incorporated into the spreadsheet for user-friendly calculation of the main components involved in facility design and operation. Outputs of the spreadsheet include size of the different rearing areas, rearing equipment, volumes of diet ingredients, other consumables, as well as personnel requirements. By adding cost factors to these components, the spreadsheet can estimate the costs of facility construction, equipment, and operation. All the output parameters can be easily generated by simply entering the target number of sterile insects required per week. For other insect species, the biological and production characteristics need to be defined and inputted accordingly to obtain outputs relevant to these species. This spreadsheet, available under http://www-naweb.iaea.org/nafa/ipc/index.html, is a powerful tool for project and facility managers as it can be used to estimate facility cost, production cost, and production projections under different rearing efficiency scenarios. (author)

  13. The FAO/IAEA interactive spreadsheet for design and operation of insect mass rearing facilities

    Energy Technology Data Exchange (ETDEWEB)

    Caceres, Carlos, E-mail: carlos.e.caceres@aphis.usda.co [International Atomic Energy Agency (IAEA), Seibersdorf (Austria). Agency' s Labs. Programme of Nuclear Techniques in Food and Agriculture; Rendon, Pedro [U.S. Department of Agriculture (USDA/APHIS/CPHST), Guatemala City (Guatemala). Animal and Plant Health Inspection. Center for Plant Health Science and Technology

    2006-07-01

    An electronic spreadsheet is described which helps users to design, equip and operate facilities for the mass rearing of insects for use in insect pest control programmes integrating the sterile insect technique. The spreadsheet was designed based on experience accumulated in the mass rearing of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), using genetic sexing strains based on a temperature sensitive lethal (tsl) mutation. The spreadsheet takes into account the biological, production, and quality control parameters of the species to be mass reared, as well as the diets and equipment required. All this information is incorporated into the spreadsheet for user-friendly calculation of the main components involved in facility design and operation. Outputs of the spreadsheet include size of the different rearing areas, rearing equipment, volumes of diet ingredients, other consumables, as well as personnel requirements. By adding cost factors to these components, the spreadsheet can estimate the costs of facility construction, equipment, and operation. All the output parameters can be easily generated by simply entering the target number of sterile insects required per week. For other insect species, the biological and production characteristics need to be defined and inputted accordingly to obtain outputs relevant to these species. This spreadsheet, available under http://www-naweb.iaea.org/nafa/ipc/index.html, is a powerful tool for project and facility managers as it can be used to estimate facility cost, production cost, and production projections under different rearing efficiency scenarios. (author)

  14. Mass rearing methods for fruit fly

    International Nuclear Information System (INIS)

    Dominguez Gordillo, J.C.

    1999-01-01

    The most common rearing methods used for mass rearing of fruit flies, with emphasis on those of economic importance in Mexico such as Anastrepha ludens (the Mexican fruit fly). Anastrepha obliqua (the mango and plum fruit fly) and the exotic fruit fly Ceratitis capitata (the Mediterranean fruit fly) are described here. (author)

  15. Dispersal and survival of sterile male (TSL strain) Mediterranean fruit flies

    International Nuclear Information System (INIS)

    Barbosa, S.; Mexia, A.; Pereira, R.

    2000-01-01

    The Mediterranean fruit fly, Ceratitis capitata (Weid.), is a major pest of fruit in the Portuguese Autonomous Region of Madeira (Vieira 1952). The Medfly attacks more than 40 species of fruit (Vieira 1952, Pereira et al. 1996). It was reported as a pest primarily below 400 m but occurred up to 700 m on the south coast. Madeira (32 deg. N, 17 deg. W) is located 980 km west-southeast of mainland Portugal. Its two principal islands (Porto Santo (50 km 2 ) and Madeira (740 km 2 )) are populated by 255,000 people. Fruit and vegetable production is widespread on Madeira island but not on Porto Santo island because of poor soil and limited rainfall. The climate of Madeira is variable, depending upon altitude and location (northern/southern). On the whole, the climate is moderated by the effects of the surrounding sea. The sterile insect technique (SIT) is a genetic method of insect control. Large numbers (frequently more than 50 million/week) of the target insect are reared in specially designed factories (Pereira et al., in press). These insects are sterilised with gamma radiation and released by aircraft into the target area. Mating between the factory reared sterile males and fertile wild females produces no progeny. Thus, if sufficient sterile males are introduced into the target area on a continuous basis there is a very high probability that fertile wild females will mate with sterile males (Hendrichs et al. 1995). Under these conditions, the birth rate of the target species is greatly reduced and will rapidly reach zero if no fertile insects are brought into the target area. Little work has been done with all male releases because it is only very recently that all male strains have been mass produced. It has been postulated that releasing only sterile male Medflies could result in better distribution and perhaps increased longevity of the released individuals. To evaluate this hypothesis, tests of longevity and dispersion of sterile males were conducted. Ground

  16. Sexual competitiveness and compatibility between mass-reared sterile flies and wild populations of Anastrepha Ludens (Diptera: Tephritidae) from different regions in Mexico

    International Nuclear Information System (INIS)

    Orozco-Davila, D.; Hernandez, R.; Meza, S.; Dominguez, J.

    2007-01-01

    The mass-reared colony of Anastrepha ludens (Loew) currently used in Mexico for suppression of the Mexican fruit fly has been in use for over 10 years. Sterile flies are released into a wide range of environmental conditions as part of an integrated area-wide approach to suppress diverse populations of this pest in the Mexican Republic. This paper assesses the performance of the sterile flies interacting with wild populations from the different environments. We investigated the sexual compatibility and competitiveness of the sterile flies when competing with wild populations from 6 representatives Mexican states: Nuevo Leon, Tamaulipas, Sinaloa, Nayarit, Michoacan, and Chiapas. Results show that the males of the wild populations differed in the time to the onset and peak of sexual activity. Nevertheless, the index of sexual isolation (ISI) reflected sexual compatibility between the populations and the mass-reared strain, indicating that the sterile individuals mate satisfactorily with the wild populations from the 6 states. The male relative performance index (MRPI) showed that the sterile male is as effective in copulating as the wild males. The female relative performance index (FRPI) reflected a general tendency for wild females to copulate in greater proportion than the sterile females, except for the strains from Tamaulipas and Chiapas. In general, the lower participation of the sterile females in copulation increases the possibilities of sterile males to mate with wild females. The relative sterility index (RSI) showed that the acceptance by wild females of the sterile males (25-55%) was similar to that of wild males. Females of the Chiapas strain showed the lowest acceptance of sterile males. Finally, the results obtained in the Fried test (which measures induced sterility in eggs) showed a competitiveness coefficient ranging from 0.2 to 0.5. This suggests that sterile males successfully compete and are compatible with flies from different geographic origins

  17. A practical, efficient and low cost diet for rearing the Mediterranean fruit fly larvae

    International Nuclear Information System (INIS)

    Manoukas, A.G.; Zografou, E.N.

    2000-01-01

    The Mediterranean fruit fly Ceratitis capitata Wied. (Diptera: Tephritidae), has been artificially reared and used for the application of the sterile insect technique and other purposes, throughout the world. The larval diet used is rather expensive and it is mixed in the rearing facility. The most expensive ingredient used in this diet is yeast which is variable in composition and has a relatively short shelf life due mainly to its high nutritional value. This is particularly true for all countries like Greece which do not manufacture brewer's yeast. Also, it is widely known that the Mediterranean fruit fly larvae grow in a wide variety of fruits and artificial diets. These fruits and artificial diets, although very different in chemical/nutritional as well as physical/ecological parameters, are successfully tolerated and utilised by the larvae. These observations prompted the initiation of research into diets containing a variety of low cost ingredients widely used in the vertebrate feed industry and easily found in any country. To our knowledge, no one has tested complete diets produced by well-established feed manufacturers for larval rearing of this insect

  18. Consultants Group Meeting on Production System Analysis and Economics for Tsetse Fly Mass-Rearing and the Use of the Sterile Insect Technique in Eradication Programmes in Africa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-07-01

    A consultants' group met in Vienna from 23 September - 3 October 1991 to explore 'Production System Analysis and Economics for Tsetse Fly Mass-rearing and the Use of the Sterile Insect Technique in Eradication Programmes in Africa'. This report is based on their observations during working visits to the Entomology Unit of the IAEA Agricultural Laboratory at Seibersdorf, and on information supplied by the tsetse team and staff of the Joint FAO/IAEA Division's Insect and Pest Control Section. The consultants conducted a technical, operational and financial review of present rearing methods, equipment, philosophies and production capacities, taking into account one of the recommendations made at the 6th Session of the ''FAO Commission on African Animal Trypanosomiasis'' held in June 1991 in Harare, Zimbabwe. This recommendation, related to the use of the Sterile Insect Technique (SIT), states that {sup F}AO, through the Joint FAO/IAEA Division, should further investigate and improve the use of sterile insects to strengthen the efficacy of tsetse surveys and, where applicable, consider teh use of the SIT to support eradication campaigns where other techniques on their own will not achieve this objective''. In investigating the potential for improved tsetse mass-rearing and analyzing the present costs of pupa/distributable sterile fly production, the consultants noted that: 1. The Seibersdorf Tsetse Unit is conducting an effective research and development programme which strives to emulate a production facility while continuing to pursue R and D. The capacity of the present facility in Seibersdorf is practically limited to a colony size of about 150,000 breeding females. The release of sterile males in an eradication campaign of economical relevance would require a colony containing more than 500,000 female flies. Such a population can only be maintained in an organizational, operational and financially justifiable manner if the rearing technology is transferred from an

  19. Mass rearing of the Medfly temperature sensitive lethal genetic sexing strain in Guatemala

    International Nuclear Information System (INIS)

    Caceres, C.; Fisher, K.; Rendon, P.

    2000-01-01

    Field tests have demonstrated the increased efficiency of the sterile insect technique (SIT) for the Mediterranean fruit fly (Ceratitis capitata Wied.), when only male Medflies are released (Robinson et al. 1986, Nitzan et al. 1993, McInnis et al. 1994, Rendon 1996). Genetic sexing strains (GSS) of Medflies, containing temperature sensitive lethal (tsl) and white pupae colour (wp) mutations (Franz et al. 1994) developed by FAO/IAEA, allow the separation of male flies from female flies. GSS technology has reached a stage where it is being used in large-scale operational programmes, such as the Moscamed Program in Guatemala. GSS based on the wp/tsl have the advantages of: 1) not requiring sophisticated equipment for sex separation, 2) a high accuracy of separation (> 99.5% males) is possible and, 3) separation is achieved during egg development, which excludes the unnecessary rearing of females (Franz et al. 1996). It was shown by Franz et al. (1994) that tsl GSS are genetically stable for many generations under small-scale rearing conditions. However, under the large-scale rearing of operational programmes such as Moscamed (Hentze and Mata 1987), a gradual loss of the sex separation mechanism through recombination remains a problem, as has been demonstrated in Guatemala during 1994-1996. This in no way precludes the use of GSS technology, but it does mean that a management system must be used to control this gradual loss of stability; a strategy for colony management which maintains a stable and high level of accuracy of male-only production. The El Pino facility, which mass produces sterile flies for the Guatemala Medflies SIT Program, has introduced a filter rearing system (FRS) (Fisher and Caceres 1999), and has demonstrated in a Medfly tsl GSS known as VIENNA 4/Tol-94, that genetic stability can be maintained. We report the operation of the FRS and its impact upon genetic stability and male-only production. The concept of the FRS has the potential to improve the

  20. Red oak borers become sterile when reared under continuous light

    Science.gov (United States)

    Jimmy R. Galford

    1975-01-01

    Red oak borers, Enaphalodes rufulus (Haldeman), reared under continuous light for 12 weeks became sterile. Sterility is thought to have been caused by light destroying vitamins essential for fertility

  1. Suppression of the Mediterranean fruit fly in Tunisia with released sterile insects

    International Nuclear Information System (INIS)

    Cheikh, M.; Howell, J.F.; Harris, E.J.; Salah, H.B.; Soria, F.

    1975-01-01

    The Government of Tunisia, U. S. Agency for International Development, and U. S. Department of Agriculture cooperatively developed a program for suppression of Ceratitis capitata (Wiedemann) in Tunisia. Mediterranean fruit flies were reared on an artificial diet, sterilized with 10 krad irradiation from a cobalt source, and the emerged adults were marked and then distributed by hand throughout the release area, 600 ha in the vicinity of Porto-Farina. Some aerial releases were made late in the season. Winter larval hosts were removed to lower the overwintering population, and sterile fly releases were begun early (Mar.1) to prevent fertile matings of flies that emerged during warm winter days. All fruit on the periphery of the release area was sprayed periodically (5 applications), as was the major fruit-growing areas within the region but outside the test zone, to minimize the possibility of fertile flies entering the release area. Daily from March to November, ca. 1,000,000 sterile flies were released. Trap catches indicated that the suppression obtained was about equal to that obtained using poison bait sprays. The early preferred host crops had no or negligible infestation (loquats, apricots, early peaches, and figs). The infestation of preferred summer fruits (peaches and figs) was reduced but not controlled. Less susceptible summer fruits were seldom infested. The estimated population was ca. 82.3 percent lower than in the previous year when no releases were made. Isolation and sterile fly distribution was inadequate to completely suppress the Mediterranean fruit fly population. (U.S.)

  2. Dispersal and longevity of wild and mass-reared Anastrepha Ludens and Anastrepha Obliqua (Diptera: Tephritidae)

    International Nuclear Information System (INIS)

    Hernandez, E.; Orozco, D.; Flores Breceda, S.; Dominguez, J.

    2007-01-01

    The rates of dispersal and survival of sterile mass-reared laboratory flies and sterile wild flies of Anastrepha ludens (Loew) and Anastrepha obliqua (Macquart) were estimated and compared with a regular rectangular array of 64 food-baited traps spaced 60 m between traps around the release point in Tapachula Chiapas, Mexico. The traps were scored every day during the first week, and then every 3 d over a 30-d period. For A. obliqua, the number of males recaptured was higher than that of females, while for A. ludens, females were recaptured more frequently than males. The recapture rate for the wild strains ranged from 0.6-24.8% for A. ludens and 1.3-16.2% for A. obliqua and the corresponding ranges for the mass-reared strains were 0.5-7.1% and 0.5-3.0% respectively. The life expectancy was 4.7 d for wild and 4.3 d for mass-reared A. obliqua males but 3 and 2 d, respectively, for wild and mass-reared A. ludens males. The net displacement of A. ludens and A. obliqua ranged approximately from 100-250 m and took place mostly on the first day. Wild A. ludens moved to the northwest from the release point while the mass-reared strain moved to the west. The A. obliqua wild flies moved to the west, while the mass-reared strain shifted to the southwest. We discuss the implications of our findings as to the spacing and frequency of sterile fly releases for the suppression of wild populations. (author) [es

  3. Production and quality assurance in the SIT Africa Mediterranean fruit fly (Diptera: Tephritidae) rearing facility in South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, B [Plant Protection Division, ARC Infruitec-Nietvoorbij Fruit, Vine and Wine Institute, Stellenbosch, 7599 (South Africa); Rosenberg, S; Arnolds, L; Johnson, J [SIT Africa (Pty) Ltd., Stellenbosch, 7599 (South Africa)

    2007-03-15

    A mass-rearing facility for Mediterranean fruit fly Ceratitis capitata (Wiedemann) was commissioned in Stellenbosch in 1999 to produce sterile male fruit flies for a sterile insect technique (SIT) project in commercial fruit orchards and vineyards in the Western Cape province of South Africa. The mass-rearing procedure was largely based on systems developed by the FAO/IAEA Agriculture and Biotechnology Laboratory, Seibersdorf, Austria. A number of genetic sexing strains were used to produce only males for release. Initial cramped rearing and quality management conditions were alleviated in 2001 with the construction of a new adult rearing room and quality control laboratory. In 2002 a comprehensive Quality Management System was implemented, and in 2003 an improved genetic sexing strain, VIENNA 8, was supplied by the FAO/IAEA Laboratory in Seibersdorf. For most of the first 3 years the facility was unable to supply the required number of sterile male Mediterranean fruit flies for the SIT program without importing sterile male pupae from another facility. From mid-2002, after the quality management system was implemented, both production and quality improved but remained below optimum. After the introduction of the VIENNA 8 genetic sexing strain, and together with an improvement in the climate control equipment, production stability, and quality assurance parameters improved substantially. The critical factors influencing production and quality were an inadequate rearing infrastructure, problems with the quality of the larval diet, and the initial absence of a quality management system. The results highlight the importance of effective quality management, the value of a stable and productive genetic sexing strain, and the necessity for a sound funding base for the mass-rearing facility. (author) [Spanish] La facilidad para criar en masa la mosca mediterranea de la fruta, Ceratitis capitata (Wiedemann) fue comisionada en Stellenbosch en 1999 para producir machos

  4. Incorporation of diapause into codling moth mass rearing: Production advantages and insect quality issues

    International Nuclear Information System (INIS)

    Bloem, Stephanie; Calkins, Carrol O.; Bloem, Ken A.

    2000-01-01

    The codling moth (CM), Cydia pomonella L. (Lepidoptera: Tortricidae) is a widely distributed species and the key pest of apples and pears in orchards of the Pacific Northwest. CM possesses facultative diapause and the mature 5th instar larva is the overwintering stage (Brown 1991). British Columbia, Canada, is attempting to eradicate CM using the sterile insect technique (SIT). The Okanagan-Kootenay Sterile Insect Release (SIR) Program began releasing sterile CM in 1994 (Dyck et al. 1993, Bloem and Bloem 1996) and results in recent years have been excellent. Despite the fact that standard rearing operations have gone extremely well, and weekly CM production has increased from 8.7 million CM per week in 1994 to 14.2 million per week in 1997, the ability to mass rear diapausing CM holds a number of advantages that are currently not available. The ability to stockpile CM larvae in diapause throughout the fall and winter months when the mass rearing facility is underutilised would: 1) provide additional CM for release during the spring/summer field season, 2) provide back-up material to guard against colony losses due to operational failures and/or pathogen outbreaks, 3) allow for a potentially more cost-effective use of the facility by maintaining production year round, 4) facilitate the development of mass rearing techniques for key parasitoids that attack the overwintering stage, 5) allow for the easy shipment (and sale) of CM to researchers around the world. Here we outline the current standard CM mass rearing procedures and discuss research that has allowed diapausing CM to be mass reared (Bloem et al. 1997). We also discuss research that suggests diapaused CM are more competitive than standard non-diapaused CM (Bloem et al. 1998)

  5. Effect of Gamma Irradiation on Mediterranean Fruit Fly, Ceratitis Capitata (Wiedemann) and Improvement of The Sterile-Insect Technique

    International Nuclear Information System (INIS)

    Sayed, W.A.A.

    2013-01-01

    The population suppression success of Mediterranean fruit fly, Ceratitis capitata (Wied.) using sterile insect technique (SIT) depends mainly upon: the release of male only, ability of sterilized males to compete with wild males in mating with wild females and discrimination of released male flies from the wild population. The effect of gamma irradiation doses on the male sterility was evaluated, to determine the level of induced sterility for achieving the balance between sterility and mating competitiveness. For optimal sterilizing dose, 8 different doses of gamma irradiation were tested. The results revealed that the doses 80, 90 and 100 Gy were the effective doses for SIT. In a field cage experiment, the mating ability, mating competitiveness and sexual compatibility were determined for the three effective sterilizing doses. The indices of sexual isolation (ISI) and the relative sterile index (RSI) indicated that mating efficiency of the dose 80 Gy was better than the doses 90 and 100 Gy. Obtained results also revealed that the competitiveness of 80 Gy irradiated males was higher than either 90 or 100 Gy irradiated males. Mutant strains, i.e. white eye white pupae strain (WeWp strain), male linked translocated strain (T strain), temperature sensitive lethal strain (tsl strain) and sergeant 2 strain (Sr 2 strain) were reared and maintained for the construction of genetic sexing strain Vienna 8- Sr 2 strain (GSS V8-Sr 2 ). The results of biological characters of GSSs revealed that, the 3 sexing strains (T, Sr 2 and V8 strains) which have Y- auto some translocation were less productive than the bisexual strain (BSS). Also, the development of tsl and GSS V 8-Sr 2 strains was delayed compared with the BSS strain. The stability of GSS V8-Sr 2 strain in the filter rearing was higher than in the mass rearing throughout 12 successive generations. The use of recombinant DNA to develop the two genetically modified strains GMSs (V8-2) and (V8-4) using insect transformation

  6. Sterile insect supply, emergence, and release

    International Nuclear Information System (INIS)

    Dowell, R.V.; Worley, J.; Gomes, P.J.

    2005-01-01

    Insect mass-rearing for a sterile insect technique (SIT) programme is designed to move beyond the large-scale rearing of insects in a laboratory to the industrial production of consistently high-quality insects for sterilization and release. Each facility reflects the unique biology of the insect reared within it, but there are some generalities for all rearing facilities. Rearing insects in self-contained modules offers flexibility, and increased safety from catastrophic occurrences, compared with using a single building which houses all facets of the rearing process. Although mechanizing certain aspects of the rearing steps helps provide a consistently high-quality insect, successful mass-rearing and delivery depends largely upon the human component. Besides production in centralized facilities, insects can be produced from purchased eggs, or nowadays, adult insects are often obtained from specialized satellite emergence/collection facilities. Interest in commercializing insect production and release is increasing. Shipping sterile insects, sometimes over long distances, is now common practice. Procedures for handling and chilling adult insects, and providing food and water prior to release, are continually being improved. Sterile insects are released via static-release receptacles, ground-release systems, or most commonly from the air. The aerial release of chilled sterile insects is the most efficient method of release, especially when aircraft flight paths are guided by a Global Positioning System (GPS) linked to a computer-controlled release mechanism. (author)

  7. Alternative Sources Of Protein And Bulking Agent For Mass Rearing Of The Mediterranean Fruit Fly, Ceratitis Capitata (WIED.), For The Sterile Insect Technique (SIT)

    International Nuclear Information System (INIS)

    SHOMAN, A.A.

    2009-01-01

    The objective of this study was to develop suitable and economic diets for mass rearing of the Mediterranean fruit fly, Ceratitis capitata (Wied.) (Diptera: Tephritidae), larvae by testing alternative sources of protein and bulking agent. Two larval diet groups for laboratory rearing of the medfly were conducted in addition to the control diet. The first group kept the sources of bulking agent constant (wheat bran) while the kind and the ratio of sources of protein were changed (brewer's yeast, soybean, schemed milk and agar). In the second group, the fiber (used for filling the pillows) and a paste of cardboard eggs box trays were used instead of wheat bran as bulking agent against the yeast and soybean as protein sources. To investigate the effect of the new sources of bulking agent and the kind or the ratio of the protein sources on the development and viability of the medfly, larval duration, pupal recovery, pupal weight, adult emergence, and flight ability were checked. The larval duration, pupal weight, adult recovery and flight ability were unaffected when soybean or a mixture from yeast, soybean, schemed milk and agar as protein sources for larval diet were used. The larvae reared on diets based on schemed milk or agar as sources of protein did not complete their life cycle. The percent of pupal recovery of larvae reread on diets of soybean or a mixture of protein sources were not affected except when larvae were reared on diets based on a mixture of soybean and schemed milk or schemed milk and agar. Larval duration was extended by one to two days more than the control when the fiber or a mixture of it with bran or paste of cardboard of eggs box was used as bulking agent. A paste of cardboard eggs box as bulking agent led to the extension of the larval duration by more than four days than in control. Pupal recovery was significantly decreased at all diets of the second group except the diet containing a mixture of 4 % fiber and 10 % bran as bulking agent

  8. Dosimetry practice for irradiation of the Mediterranean fruit fly Ceratitis capitata (Wied.)

    International Nuclear Information System (INIS)

    Zavala, J.L.; Fierro, M.M.; Schwarz, A.J.; Orozco, D.H.; Guerra, M.

    1985-01-01

    In a sterile insect technique (SIT) programme the sterility of mass-reared insects, in our case Mediterranean fruit flies, is of primary importance. Mediterranean fruit fly pupae are irradiated in an AECL-CP-JS-7400 irradiator. Originally the capacity was 31,300 Ci, but because of the natural decay of cobalt, the actual source strength is 14,836 Ci. Thus, the dose with which the pupae are irradiated is 14.5 +- 1 krad (145 +- 10 Gy). A great risk in the daily release of sterile flies is that some batches of fertile flies may also be released. To ensure that this does not occur, continuous dosimetric check-ups have to routinely be carried out. Fricke dosimetry is ideal for this purpose because it has a range of response to doses of 4 to 40 krad (40 to 400 Gy) and because it is an economic and simple dosimetric system. (author)

  9. Calling behavior of mass-reared and wild Anastrepha serpentina (Diptera: Tephritidae).

    Science.gov (United States)

    Castrejón-Gómez, Victor R; Lascares, Shaila; Malo, Edi A; Toledo, Jorge; Rojas, Julio C

    2007-08-01

    The calling behavior of mass-reared and wild males of Anastrepha serpentina (Wiedemann) (Diptera: Tephritidae) was studied both in the laboratory and in field cage tests. In the laboratory, density (1, 5, and 10 males per container), age, and hour of day significantly affected calling behavior. Mass-reared males called independently of density, whereas wild males only called at densities of 5 and 10 individuals. Males of both strains started calling when they were 5-7 d old. The daily pattern of male calling was similar in both strains, starting at 0730 hours, and reaching a peak at 1330-1630 hours. Field cage tests showed that mass-reared males started calling when they were 5d old; the period of peak calling was when males were 8-9 d old. In contrast, wild males began calling when they were 10 d old, reaching peaks when males were 13, 15, and 18 d old. Wild males tended to form leks to call during each day of the experiment, whereas mass-reared males only formed leks during 2 d, both strains displaying very low levels. During field cage tests, males, independently of strain, displayed two calling peaks, one peak in the morning and one peak in the afternoon, whereas males observed in the laboratory only showed a single calling peak. The results are discussed in view of the effects of mass rearing A. serpentina males in relation to potential use of the sterile insect technique.

  10. Composition of Mediterranean fruit fly third instar larvae (Diptera: Tephritidae) and diet: Nutrient balance studies on amino acids, minerals and nutrient composition in fresh and spent mass rearing diets

    International Nuclear Information System (INIS)

    Chan, Harvey T. Jr.; Jang, Eric B.; Ako, Harry; Niino-Duponte, Ruth Y.; Carpenter, James R.

    2000-01-01

    Mass production of the Mediterranean fruit fly (Medfly) larvae, Ceratitis capitata Wiedemann, requires a rearing diet (Tanaka et al. 1969 1970) of which the nutrient requirements and digestibility have not been established. Setbacks in rearing productivity from the expected 100% yield to as low as 3% yield may occasionally be directly attributed to insecticide contamination or a variety of possible cause(s) (Kobayashi, 1993). These causes include inadequate nutrition, poor diet formulation, overcrowding of either microorganisms or Drosophila, or to the inherent processes of oxidative or microbial deterioration of nutrients. The purpose of this study was to establish the nutritional status of the Mediterranean fruit fly diet through a material balance study for changes in proximate composition (i.e., moisture, protein, fat, ash, carbohydrates), amino acids, minerals between fresh and spent diets, and in the fruit fly larvae themselves

  11. Genetic sexing strains in Mediterranean fruit fly, an example for other species amenable to large-scale rearing for the sterile insect technique

    International Nuclear Information System (INIS)

    Franz, G.

    2005-01-01

    Through genetic and molecular manipulations, strains can be developed that are more suitable for the sterile insect technique (SIT). In this chapter the development of genetic sexing strains (GSSs) is given as an example. GSSs increase the effectiveness of area-wide integrated pest management (AW-IPM) programmes that use the SIT by enabling the large-scale release of only sterile males. For species that transmit disease, the removal of females is mandatory. For the Mediterranean fruit fly Ceratitis capitata (Wiedemann), genetic sexing systems have been developed; they are stable enough to be used in operational programmes for extended periods of time. Until recently, the only way to generate such strains was through Mendelian genetics. In this chapter, the basic principle of translocation-based sexing strains is described, and Mediterranean fruit fly strains are used as examples to indicate the problems encountered in such strains. Furthermore, the strategies used to solve these problems are described. The advantages of following molecular strategies in the future development of sexing strains are outlined, especially for species where little basic knowledge of genetics exists. (author)

  12. Fitness of Mass-Reared Males of Anastrepha obliqua (Diptera: Tephritidae) Resulting From Mating Competition Tests in Field Cages.

    Science.gov (United States)

    Hernández, Emilio; Liedo, Pablo; Toledo, Jorge; Montoya, Pablo; Perales, Hugo; Ruiz-Montoya, Lorena

    2017-12-05

    The sterile insect technique uses males that have been mass-reared in a controlled environment. The insects, once released in the field, must compete to mate. However, the mass-rearing condition supposes a loss of fitness that will be noticeable by wild females. To compare the fitness of wild males and mass-reared males, three competition settings were established. In setting 1, wild males, mass-reared males and wild females were released in field cages. In setting 2, wild females and wild males were released without competition, and in setting 3, mass-reared males and mass-reared females were also released without competition. Male fitness was based on their mating success, fecundity, weight and longevity. The fitness of the females was measured based on weight and several demographic parameters. The highest percentage of mating was between wild males and wild females between 0800 and 0900 h in the competition condition, while the mass-reared males started one hour later. The successful wild males weighed more and showed longer mating times, greater longevity and a higher number of matings than the mass-reared males. Although the mass-reared males showed the lowest percentage of matings, their fecundity when mating with wild females indicated a high fitness. Since the survival and fecundity of wild females that mated with mass-reared males decreased to become similar to those of mass-reared females that mated with mass-reared males, females seem to be influenced by the type of male (wild or mass-reared). © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Genetics and ecology of colonization and mass rearing of Hawaiian fruit flies (Diptera: Tephritidae) for use in sterile insect control programs

    International Nuclear Information System (INIS)

    Saul, S.H.; McCombs, S.D.

    1995-01-01

    It is critical to maintain the genetic, physiological and behavioral competence of colonized populations of insect species, such as fruit flies, which are reared for release in sterile insect and other genetic control programs. Selective pressures associated with the mass rearing process affect this competence, but the underlying mechanisms of genetic change arc largely unknown. However, competence is often an operational goal achieved by manipulating environmental factors without possessing precise genetic knowledge of alleles and their marginal effects on the desired traits. One goal of this paper is to show that the precise genetic and statistical analysis of components that determine competence in a broad sense or fitness in the narrower ecological sense, is extremely difficult. We can gel contradictory results from the different methods for estimating genetic variation in tephritid populations. We observe low levels of allozyme variation, but high levels of recessive mutants in inbred populations. We propose that genetic variability may be maintained in colonized and mass reared laboratory populations by balanced lethal systems and that the introduction of fresh genetic material may reduce, not increase, fitness. We require rigorous and precise models of directional selection in the laboratory and selective forces in the natural environment to aid our understanding of dynamic changes in courtship and mating behavior under artificial conditions. We have chosen to examine the lek model as an example of an idea whose usefulness has yet to be determined by test ing and validation. The inclusion of lek forming ability in genetic models will be depen dent on rigorously establishing the validity of the lek model for each tephritid species

  14. Mass rearing and radiation sterilization of tsetse flies. Part of a coordinated programme on control and eradication of tsetse flies by the sterile insect technique

    International Nuclear Information System (INIS)

    Offori, E.

    1980-12-01

    Studies were conducted with the tsetse flies Glossina palpalis palpalis, G.p. gambiensis and G. tachinoides to evaluate the practicality in Ghana of various laboratory and field procedures used to conduct a sterile insect release programme. Investigations revealed that in colony rearing rabbits, guinea pigs and goats could be used as host animals and that alternation of hosts had little effect on colony performance. Over 90% sterility in 10-day-old males irradiated at 12 kR was obtained with little or no effect on survival. At 15 kR, 98% sterility was obtained but with some loss in viability observed. In mating experiments, G. p. palpalis and G. p. gambiensis mated readily with each other and indicated that sterile males of one sub-species could be released with advantage into an area predominantly occupied by the other sub-species. In field tests, the moving vehicle traps proved most efficient of the various sampling techniques evaluated. It was noted that in spite of the rapid expansion of the city of Accra, tsetse flies were still present within a distance of 4 km of the city

  15. Development and mass-rearing of cabbage pests (Plutella maculipennis and crocidolomia binotalis) on semisynthetic diets

    Energy Technology Data Exchange (ETDEWEB)

    Sjarief, Sri Hariani (National Atomic Energy Agency, Jakarta (Indonesia). Pasar Djumat Research Centre)

    1983-07-01

    Heavy damage to cabbage plantations in Indonesia as caused by plutella maculipennis and crocidolomia binotalis furnished economic justification of research on the sterile-male approach to eradication of this species. The sterile-male technique requires a mass-production of these insects, therefore studies were initiated on rearing larvae in artificial diets. A series of media based on biochemical and biological ingredients were tested. Larvae of the second instar were kept on artificial medium up to 14 days reaching the fourth instar (prepupae). The observation was carried out on the rates pupation, adult emergence and eggs production, continuous to their progenies. No morphological damaged are found on the diet-reared insects. A complete absence of cholesterol in the diet for crocidolomia binotalis brought on the emergence of non-fecund adults.

  16. Genetic quality control in mass-reared melon flies

    International Nuclear Information System (INIS)

    Miyatake, T.

    2002-01-01

    Quality control in mass-reared melon flies, Bactrocera cucurbitae, after eradication is discussed, based on the results of artificial selection experiments. First, a brief history of quality control in mass-rearing of insects is described. In practical mass- rearing of melon fly, many traits have already been differentiated between mass-reared and wild flies. These differing traits are reviewed and the factors which caused these differences are considered. It was considered that the differences between wild and mass-reared melon flies depended on the selection pressures from the mass-rearing method. Next, the results of several artificial selection experiments using the melon fly are reviewed. Finally, consideration is given to some correlated responses to artificial selection in mass-rearing. Longevity that is correlated to early fecundity was successfully controlled by artificial selection for reproduction in the mass-rearing system. On the basis of these results, an improved method for quality control in mass-reared melon fly with considerations for quantitative genetics is discussed

  17. The development and mass-rearing of cabbage pests (Plutella maculipennis and crocidolomia binotalis) on semisynthetic diets

    International Nuclear Information System (INIS)

    Sjarief, Sri Hariani

    1983-01-01

    Heavy damage to cabbage plantations in Indonesia as caused by plutella maculipennis and crocidolomia binotalis furnished economic justification of research on the sterile-male approach to eradication of this species. The sterile-male technique requires a mass-production of these insects, therefore studies were initiated on rearing larvae in artificial diets. A series of media based on biochemical and biological ingridients were tested. Larvae of the second instar were kept on artificial medium up to 14 days reaching the fourth instar (prepupae). The observation was carried out on the rates pupation, adult emergence and eggs production, continuoous to their progenies. No morphological damaged are found on the diet-reared insects. A complete absence of cholesterol in the diet for crocidolomia binotalis brought on the emergence of non-fecund adults. (author)

  18. Mass rearing the Old World screw-worm fly, Chrysomya bezziana

    International Nuclear Information System (INIS)

    Mahon, R.J.; Hamdan bin Ahmad

    2000-01-01

    Many countries within the tropics are afflicted with one of two species of screw-worm, either the New World screw-worm fly Cochliomyia hominivorax Coquerel (NWSWF), or the Old World screw-worm fly, Chrysomya bezziana Villenuve (OWSWF). In nature, larvae of both species are obligate parasites and feed on the living flesh of mammals and to a lesser extent, birds. Female flies lay eggs at the site of a pre-existing wound or near body orifices of the host. First instar larvae feed superficially on the wound; however, larger larvae use their hooked mouthparts to burrow deep into the flesh of the host. Damaged blood vessels provide a steady stream of blood and plasma that typically oozes from the infested wound. The wound also acquires a characteristic odour. Presumably, some of the volatile components emanating from the wound, also provide strong signals to gravid female flies, as once infested, wounds become far more attractive as a site to lay eggs than uninfested wounds. As the number of larvae increases, the myiasis enlarges and the well-being of the host is threatened. In areas where gravid female SWF are numerous, the wound has little chance to heal, thus death of the host is likely unless the wound is treated and re-infestation prevented. While New and Old World species are distantly related, they are remarkably similar ecologically and in their biological characteristics. Wherever either species occurs, it is considered a serious pest of livestock. Australia is fortunate that neither species of the screw-worm is present despite evidence that extensive areas appear environmentally suitable. The OWSWF is considered the most serious threat to Australia as it is present in the neighbouring countries of Papua New Guinea and Indonesia. It is envisaged that the sterile insect release method (SIRM) will be employed to eradicate the OWSWF if it becomes established in Australia. To facilitate such a programme, and to reduce delays in constructing a suitable mass rearing

  19. Automation for tsetse mass rearing for use in sterile insect technique programmes. Final report of a co-ordinated research project 1995-2001

    International Nuclear Information System (INIS)

    2003-05-01

    The rearing of tsetse flies for the sterile insect technique has been a laborious procedure in the past. The purpose of this co-ordinated research project (CRP) 'Automation for tsetse mass rearing for use in sterile insect technique programmes' was to develop appropriate semiautomated procedures to simplify the rearing, reduce the cost and standardize the product. Two main objectives were accomplished. The first was to simplify the handling of adults at emergence. This was achieved by allowing the adults to emerge directly into the production cages. Selection of the appropriate environmental conditions and timing allowed the manipulation of the emergence pattern to achieve the desired ratio of four females to one male with minimal un-emerged females remaining mixed with the male pupae. Tests demonstrated that putting the sexes together at emergence, leaving the males in the production cages, and using a ratio of 4:1 (3:1 for a few species) did not adversely affect pupal production. This has resulted in a standardized system for the self stocking of production cages. The second was to reduce the labour involved in feeding the flies. Three distinct systems were developed and tested in sequence. The first tsetse production unit (TPU 1) was a fully automated system, but the fly survival and fecundity were unacceptably low. From this a simpler TPU 2 was developed and tested, where 63 large cages were held on a frame that could be moved as a single unit to the feeding location. TPU 2 was tested in various locations, and found to satisfy the basic requirements, and the adoption of Plexiglas pupal collection slopes resolved much of the problem due to light distribution. However the cage holding frame was heavy and difficult to position on the feeding frame and the movement disturbed the flies. TPU 2 was superseded by TPU 3, in which the cages remain stationary at all times, and the blood is brought to the flies. The blood feeding system is mounted on rails to make it

  20. Development of quality control procedures for mass produced and released Bactrocera Philippinensis (Diptera: Tephritidae) for sterile insect technique programs

    International Nuclear Information System (INIS)

    Resilva, S.; Obra, G.; Zamora, N.; Gaitan, E.

    2007-01-01

    Quality control procedures for Bactrocera philippinensis Drew and Hancock 1994 (Diptera: Tephritidae) used in sterile insect technique (SIT) programs were established in the mass rearing facility at the Philippine Nuclear Research Institute. Basic studies on pupal irradiation, holding/packaging systems, shipping procedures, longevity, sterility studies, and pupal eye color determination in relation to physiological development at different temperature regimes were investigated. These studies will provide baseline data for the development of quality control protocols for an expansion of B. philippinensis field programs with an SIT component in the future. (author) [es

  1. Exploitation of the Medfly Gut Microbiota for the Enhancement of Sterile Insect Technique: Use of Enterobacter sp. in Larval Diet-Based Probiotic Applications.

    Directory of Open Access Journals (Sweden)

    Antonios A Augustinos

    Full Text Available The Mediterranean fruit fly (medfly, Ceratitis capitata, is a pest of worldwide substantial economic importance, as well as a Tephritidae model for sterile insect technique (SIT applications. The latter is partially due to the development and utilization of genetic sexing strains (GSS for this species, such as the Vienna 8 strain, which is currently used in mass rearing facilities worldwide. Improving the performance of such a strain both in mass rearing facilities and in the field could significantly enhance the efficacy of SIT and reduce operational costs. Recent studies have suggested that the manipulation of gut symbionts can have a significant positive effect on the overall fitness of insect strains. We used culture-based approaches to isolate and characterize gut-associated bacterial species of the Vienna 8 strain under mass rearing conditions. We also exploited one of the isolated bacterial species, Enterobacter sp., as dietary supplement (probiotic to the larval diet, and we assessed its effects on fitness parameters under the standard operating procedures used in SIT operational programs. Probiotic application of Enterobacter sp. resulted in improvement of both pupal and adult productivity, as well as reduced rearing duration, particularly for males, without affecting pupal weight, sex ratio, male mating competitiveness, flight ability and longevity under starvation.

  2. Exploitation of the Medfly Gut Microbiota for the Enhancement of Sterile Insect Technique: Use of Enterobacter sp. in Larval Diet-Based Probiotic Applications

    Science.gov (United States)

    Papadopoulos, Nikos T.; Abd-Alla, Adly M. M.; Cáceres, Carlos; Bourtzis, Kostas

    2015-01-01

    The Mediterranean fruit fly (medfly), Ceratitis capitata, is a pest of worldwide substantial economic importance, as well as a Tephritidae model for sterile insect technique (SIT) applications. The latter is partially due to the development and utilization of genetic sexing strains (GSS) for this species, such as the Vienna 8 strain, which is currently used in mass rearing facilities worldwide. Improving the performance of such a strain both in mass rearing facilities and in the field could significantly enhance the efficacy of SIT and reduce operational costs. Recent studies have suggested that the manipulation of gut symbionts can have a significant positive effect on the overall fitness of insect strains. We used culture-based approaches to isolate and characterize gut-associated bacterial species of the Vienna 8 strain under mass rearing conditions. We also exploited one of the isolated bacterial species, Enterobacter sp., as dietary supplement (probiotic) to the larval diet, and we assessed its effects on fitness parameters under the standard operating procedures used in SIT operational programs. Probiotic application of Enterobacter sp. resulted in improvement of both pupal and adult productivity, as well as reduced rearing duration, particularly for males, without affecting pupal weight, sex ratio, male mating competitiveness, flight ability and longevity under starvation. PMID:26325068

  3. Medfly Gut Microbiota and Enhancement of the Sterile Insect Technique: Similarities and Differences of Klebsiella oxytoca and Enterobacter sp. AA26 Probiotics during the Larval and Adult Stages of the VIENNA 8D53+ Genetic Sexing Strain

    Directory of Open Access Journals (Sweden)

    Georgios A. Kyritsis

    2017-10-01

    Full Text Available The Mediterranean fruit fly, Ceratitis capitata, is a major agricultural pest worldwide. The development of genetic sexing strains (GSSs for this species that allows male-only sterile insects releases has boosted the effectiveness of the environmental friendly pest control method known as the sterile insect technique. The last generation of these strains, the VIENNA 7 and VIENNA 8, are currently used in all mass rearing facilities worldwide and are considered as models for such pest control applications. The sterile insect technique depends on the rearing of sufficient numbers of adequate “biological quality” laboratory flies to be released in the field. Currently, there is an increasing amount of studies focusing on the characterization of the symbiotic communities and development of probiotic diets. In our study, two bacterial isolates, an Enterobacter sp. (strain AA26 and a Klebsiella oxytoca strain, were used as probiotics in larval and adult diet. These strains have been shown to be beneficial, affecting several aspects related to the rearing efficiency and biological quality of the medfly VIENNA 8D53+ GSS. Our results demonstrate the effect of K. oxytoca on the developmental duration of the immature stages and, to some extent, on flight ability. On the other hand, our study does not support the presence of any beneficial effect of (a K. oxytoca on pupal and adult recovery and adults’ survival under stress conditions when provided as a larval diet supplement and (b K. oxytoca and Enterobacter sp. AA26 on mating competitiveness when provided as adult diet supplements. Possible explanations for inconsistencies with previous studies and the need for universalizing protocols are discussed. Our findings, combined with previous studies can support the sterile insect technique, through the improvement of different aspects of mass rearing and biological properties of laboratory reared insect pests.

  4. Sterile insect technique and radiation in insect control

    International Nuclear Information System (INIS)

    1982-01-01

    Out of 39 papers and 6 summaries of the poster presentations published in this proceeding series, 23 respectively fall within the INIS subject scope. Four main topics were covered: a review of the sterile insect technique against various insect pests; its application to tsetse flies in eradication programmes; quality control of mass-reared insects for release; and the development of genetic approaches to insect mass rearing and control. Other topics emphasized integrated pest management, computer models and radioisotope labelling

  5. The Sterile Insect Technique (SIT) against tsetse flies

    International Nuclear Information System (INIS)

    1984-01-01

    The video gives general information on the reproductive anatomy and the reproductive cycles of tsetse flies, shows in detail the steps to make a membrane for food supply of mass-reared flies, and explains how their feed is prepared and processed. The different stages of mass-rearing of flies, including their irradiation and the effects of irradiation on eggs and spermatozoa, are demonstrated. The video also introduces the insect sterilization programme BICOT carried out in Nigeria

  6. The Sterile Insect Technique (SIT) against tsetse flies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1985-12-31

    The video gives general information on the reproductive anatomy and the reproductive cycles of tsetse flies, shows in detail the steps to make a membrane for food supply of mass-reared flies, and explains how their feed is prepared and processed. The different stages of mass-rearing of flies, including their irradiation and the effects of irradiation on eggs and spermatozoa, are demonstrated. The video also introduces the insect sterilization programme BICOT carried out in Nigeria

  7. Effects of pre-irradiation conditioning of Medfly pupae (Diptera: Tephritidae): Hypoxia and quality of sterile males

    International Nuclear Information System (INIS)

    Nestel, D.; Nemny-Lavy, E.; Islam, S.M.; Wornoayporn, V.; Caceres, C.

    2007-01-01

    Irradiation of pupae in sterile insect technique (SIT) projects is usually undertaken in hypoxic atmospheres, which have been shown to lessen the deleterious effects of irradiation on the quality of adult sterile flies. Although this is the accepted technology in most mass-rearing and sterilization facilities, to date no information has been generated on the actual levels of oxygen (O 2 ) in pupae-packing containers during irradiation. The present study utilized recently-developed technology to investigate the O 2 level inside bags in which pupae of Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) are packed prior to irradiation, the ability of pupae to create hypoxic environments in these bags, and the effect of O 2 atmospheres on the quality of irradiated males. Pupae, 1 d before adult emergence, were shown to deplete the O 2 level in sealed bags in approximately 1 h. The rate of O 2 consumption was dependent upon pupal age and incubation temperature. Incubation temperature did not significantly affect the quality of pupae or mating capacity of resultant adult males if pupae were irradiated under maximal hypoxic conditions inside packing bags. In contrast, mating competitiveness drastically decreased when pupae were irradiated under ambient O 2 conditions, with the packing bag open. There was no difference in the mating capacity of males when pupae were irradiated in sealed bags under either 10% or 2% O 2 levels, or under maximal hypoxia. Normal doses of fluorescent dye, applied to pupae to mark sterile flies, did not affect the ability of pupae to create hypoxic conditions inside packing bags, nor the quality control parameters of either pupae or adults. Current practices in mass-rearing facilities are discussed in the light of these results. (author) [es

  8. Sterility induction in tsetse

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, C F [London School of Hygiene and Tropical Medicine (UK); Langley, P A [Bristol Univ. (UK)

    1982-01-01

    The first laboratory and field experiments on genetic control were with tsetse flies, and they made use of the sterility in crosses and hybrids between closely related species of the Glossina morsitans complex. Backcrosses indicate that there are two separate sterility mechanisms involved: (a) genetic incompatibility between a mother and the products of alien genes in the embryo or larva in the uterus; (b) inability of hybrid males to inseminate due to incompatibility of their X-chromosomes with an alien Y or autosomes. The two largest sterile male release programmes have been in Tanzania and Upper Volta, and have used irradiation at the pupal or adult stage, respectively, for the production of sterility. Male tsetse are remarkably resistant to radiosterilization and, with the doses required to induce dominant lethals in more than 95% of sperms, premature senescence and lethargic behaviour of the males tends to result. With G. morsitans irradiated at the puparial stage these effects can be alleviated by the use of a nitrogen atmosphere during irradiation. If the puparia are then transferred to air at 11/sup 0/C for transport to the release site, immediate emergence occurs on re-warming after arrival. This advantageous procedure was used for the releases in Tanzania. In addition to dominant lethals, irradiation also produces chromosome translocations which cause inherited partial sterility. A homozygous translocation line was selected but this example did not have sufficient fitness to be used in a mass rearing programme. Chemosterilants can be applied by pupal dipping, adult contact with deposits or in aerosols. Studies are now in progress on their use in association with odour-baited traps or pheromone-baited decoys as a means of sterilizing the wild population and thus avoiding the costly and difficult process of mass rearing tsetse.

  9. Mass rearing of the olive fruit fly, Dacus oleae (Gmelin), at ''Democritos''

    International Nuclear Information System (INIS)

    Tsitsipis, J.A.

    1975-01-01

    Production of more than 4.5 million olive fruit fly pupae within a 4-month period during the summer and autumn of 1973, at an approximate cost of US $ 1 per 1000 pupae, was made possible by introducing certain improvements in the formerly used rearing system. Replacement of the adult liquid diet by a solid one and less frequent changing of the water supply saved labour; better timing in the egg collection improved hatchability. Incubation of the eggs in 0.3% propionic acid followed by their surface sterilization drastically cut down or eliminated previous sporadically appearing microbial contaminations. Most important, a new larval diet (T), which is much easier to prepare and handle, has doubled pupal yield. A new caging and egging system under development provides a higher egg production and requires far less labour. Preliminary promising results on new larval diets and modifications in the various steps of the rearing procedure will hopefully contribute to achieving the much lower costs needed even in a moderate-scale mass-release programme. (author)

  10. Effect of acclimation to outdoor condition on the sexual performance of mass-produced Medflies (Diptera: Tephritidae)

    International Nuclear Information System (INIS)

    Pereira, R.; Silva, N.; Quintal, C.; Abreu, R.; Andrade, J.; Dantas, L.

    2007-01-01

    Application of the sterile insect technique (SIT) as part of integrated area-wide programs to control the Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) require that the released males attract wild females and transfer sterile sperm. However, knowledge about male sexual performance after they are released is scarce. We conducted a study to evaluate male sexual performance in field cage tests, according to standard quality control procedures. Mass-reared 5-d-old sterile males from the genetic sexing strain VIENNA 7mix2000 were acclimated for 0, 1, and 3 d to outdoor conditions before competing with wild males for wild females. Although the proportion of mating (PM) in the test was satisfactory, the resulting relative sterility index (RSI) data showed no significant differences among the treatments. The data indicate that pre-conditioning males to outdoor conditions in Madeira did not confer an advantage in field cage sexual performance. (author) [es

  11. The Sterile Insect Technique:Current and Future Prospects

    International Nuclear Information System (INIS)

    ALRubeai, H.F.

    2004-01-01

    Considering the importance of the Key insect pests and their potential for economic and environmental impact, such species are the targets for area-wide approaches including in some cases the use of SIT. At the heart of the SIT is genetic sterility that is introduced into the target population by releasing large numbers of sterile insects . The development of an SIT package for a Key pest, involving mass rearing and aerial dispersion, as well as field monitoring and a suppression system. Losses caused by insect pests throughout the developing world will continue to be unacceptably high in the foreseeable future. Therefore, the economic feasibility of non-chemical pest control tools, including biologically -based methods such as SIT, will become increasingly apparent . This study include an overview of the basic scientific principles of SIT , is successful applications and related mass rearing and irradiation facilities over the world. (author)

  12. Efficiency of two larval diets for mass-rearing of the mosquito Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    J G Bond

    Full Text Available Aedes aegypti is a major vector of arboviruses that may be controlled on an area-wide basis using the sterile insect technique (SIT. Larval diet is a major factor in mass-rearing for SIT programs. We compared dietary effects on immature development and adult fitness-related characteristics for an International Atomic Energy Agency (IAEA diet, developed for rearing Ae. albopictus, and a standardized laboratory rodent diet (LRD, under a 14:10 h (light:dark photoperiod ("light" treatment or continuous darkness during larval rearing. Larval development was generally fastest in the IAEA diet, likely reflecting the high protein and lipid content of this diet. The proportion of larvae that survived to pupation or to adult emergence did not differ significantly between diets or light treatments. Insects from the LRD-dark treatment produced the highest proportion of male pupae (93% at 24 h after the beginning of pupation whereas adult sex ratio from the IAEA diet tended to be more male-biased than that of the LRD diet. Adult longevity did not differ significantly with larval diet or light conditions, irrespective of sex. In other aspects the LRD diet generally performed best. Adult males from the LRD diet were significantly larger than those from the IAEA diet, irrespective of light treatment. Females from the LRD diet had ~25% higher fecundity and ~8% higher egg fertility compared to those from the IAEA diet. Adult flight ability did not differ between larval diets, and males had a similar number of copulations with wild females, irrespective of larval diet. The LRD diet had lower protein and fat content but a higher carbohydrate and energetic content than the IAEA diet. We conclude that the LRD diet is a low-cost standardized diet that is likely to be suitable for mass-rearing of Ae. aegypti for area-wide SIT-based vector control.

  13. Role of population genetics in the sterile insect technique

    International Nuclear Information System (INIS)

    Krafsur, E.S.

    2005-01-01

    The detection and analysis of genetic variation in natural and laboratory populations are reviewed. The application of population genetic methods and theory can help to plan and evaluate the implementation of area-wide integrated pest management (AW-IPM) programmes that use the sterile insect technique (SIT). Population genetic studies can play an important role in estimating dispersal rates and thus gene flow among target populations, determining if sibling species exist, establishing the origin of outbreaks or reintroductions, and supporting the quality control of mass-reared colonies. The target's population history may be examined, in terms of 'bottlenecks', range fragmentations, and expansions. Genetic methods can be helpful in distinguishing wild insects from released sterile or substerile ones, and in ascertaining, together with mating cross-compatibility studies, the compatibility of mass-reared colonies with target wild insects. (author)

  14. Blood Collection from Local Abattoirs for Mass Production of Tsetse Flies to be used in the Sterile Insect Technique

    Energy Technology Data Exchange (ETDEWEB)

    Byamungu, M B; Kiimbisa, B; Matembo, S; Mashenga, G [Tsetse and Trypanosomiasis Research Institute, P.O. Box 1026, Tanga (Tanzania, United Republic of)

    2012-07-15

    The mass production of tsetse flies (Glossina spp.) for the sterile insect technique (SIT) requires a supply of quality blood. For some years already cattle blood has been used as food for laboratory reared flies. The blood is collected from an abattoir using standard procedures. The collection procedures, handling and storage require aseptic conditions to avoid contamination of the blood, which could be fatal to the flies. Fly mortality caused by low quality blood endangers the success of mass rearing. To rear healthy flies with good survival and production the blood should be of good quality - free of contamination and with a packed cell volume (PCV) above 25%. The present work involved the seasonal collection of blood from abattoirs in the United Republic of Tanzania (Tanga, Arusha, Dodoma, Dar-es-salaam). Dodoma was identified as having the best conditions for blood collection. To assess the quality of the blood as a diet for tsetse, blood was screened for the presence of bacteria, and the pathogens were identified. Protocols were developed for blood quality assurance. (author)

  15. Guidance for packing, shipping, holding and release of sterile flies in area-wide fruit fly control programmes

    International Nuclear Information System (INIS)

    Enkerlin, W.

    2007-01-01

    This guidance represents the recommendations, reached by consensus of an international group of experts, on the standard procedures for the packing, shipping, holding and release of mass reared and sterilized tephritid flies that are to be used in area-wide programmes that include the Sterile Insect Technique (SIT). The majority of the procedures were initially designed specifically for the Mediterranean fruit fly Ceratitis capitata (Wiedemann) (or Medfly), but they are applicable, with minor modifications, for other tephritid species such as those in the genera Anastrepha, Bactrocera and Dacus. The guidance is designed to be a working document that can be subject to periodic updates due to technological developments and research contributions. Future editions will endeavour to include more specific recommendations for other species of fruit flies as the relevant data become available. The procedures described in this guidance will help ensure that released sterile fruit flies will be of optimal quality and that the resulting field density of these flies will be as closely aligned to the individual programme needs. It is hoped that this guidance will help to quickly identify and correct problems in programme effectiveness, resulting from less than optimal emergence and release conditions

  16. The sterile insect technique: Cost-effective control of the Mediterranean fruit fly

    International Nuclear Information System (INIS)

    Gomez Riera, Pablo

    2001-01-01

    occur and must be dealt with in Florida and California, Mexico and Chile. Fruit flies, like any other pest, have been attacked with biocides at the farm level. Citrus is an instructive example. Citrus flowers and fruits twice a year, and various species and varieties provide year-round harvests. Biocides are typically applied to citrus every 10-15 days. Even so, the effectiveness is usually only 70-80%, due to uncontrolled neighboring farms, untreated hosts, problems with the spraying equipment, dose miscalculations, etc. Aerial applications of bait sprays to wider areas are more expensive, require a regional plan, and can represent a major impact to the environment. All means of application can leave pesticide residues in the fruit. Trade in fresh fruits and vegetables is being liberalized on a world-wide basis as part of globalization. At the same time, local consumption of fresh products is increasing in the search for a healthier life. Pesticides are increasingly less acceptable in both the export trade and local markets. Newly adopted food safety and phytosanitary standards require the establishment of either low prevalence or entirely fruit fly-free areas. Environmental considerations reinforce the already favorable cost-benefit picture for the Sterile Insect Technique (SIT) as an alternative to controls that use chemicals alone. The SIT has been in use since the 1950s. The aim of the technique is to disrupt the life cycle of the fly, mating the wild population with sterile flies reared at a 'fly factory'. Sterilization is accomplished by exposing insects to a specific dose of gamma radiation emitted by radioisotopes (cobalt-60 or cesium-137). Irradiation is a central and indispensable part of the total SIT process: every insect among millions produced each week must to be sterilized. No other method is available to achieve sterilization; chemosterilants, linear accelerators and the like have proven less cost-effective

  17. The sterile insect technique: Cost-effective control of the Mediterranean fruit fly

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Riera, Pablo [INTA La Consulta, Mendoza (Argentina)

    2001-07-01

    occur and must be dealt with in Florida and California, Mexico and Chile. Fruit flies, like any other pest, have been attacked with biocides at the farm level. Citrus is an instructive example. Citrus flowers and fruits twice a year, and various species and varieties provide year-round harvests. Biocides are typically applied to citrus every 10-15 days. Even so, the effectiveness is usually only 70-80%, due to uncontrolled neighboring farms, untreated hosts, problems with the spraying equipment, dose miscalculations, etc. Aerial applications of bait sprays to wider areas are more expensive, require a regional plan, and can represent a major impact to the environment. All means of application can leave pesticide residues in the fruit. Trade in fresh fruits and vegetables is being liberalized on a world-wide basis as part of globalization. At the same time, local consumption of fresh products is increasing in the search for a healthier life. Pesticides are increasingly less acceptable in both the export trade and local markets. Newly adopted food safety and phytosanitary standards require the establishment of either low prevalence or entirely fruit fly-free areas. Environmental considerations reinforce the already favorable cost-benefit picture for the Sterile Insect Technique (SIT) as an alternative to controls that use chemicals alone. The SIT has been in use since the 1950s. The aim of the technique is to disrupt the life cycle of the fly, mating the wild population with sterile flies reared at a 'fly factory'. Sterilization is accomplished by exposing insects to a specific dose of gamma radiation emitted by radioisotopes (cobalt-60 or cesium-137). Irradiation is a central and indispensable part of the total SIT process: every insect among millions produced each week must to be sterilized. No other method is available to achieve sterilization; chemosterilants, linear accelerators and the like have proven less cost-effective.

  18. Two new pupal sexing strains in the Mediterranean fruit fly, Ceratitis capitata (Wied.)

    International Nuclear Information System (INIS)

    Zapater, M.

    1990-01-01

    A genetic sexing system in the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann), is urgently required in order to reduce the costs of mass rearing and to prevent punctures in fruit made by the ovipositors of sterilized females. Two genetic sexing strains, T(Y,5)122; T:Y(wp), white pupae, and T(Y,3,5)11; T:Y(dp + wp + ), were isolated and studied in connection with their possible use in a mass rearing programme. Both strains have males emerging from wild type brown pupae and females emerging from mutant pupae; they are stable up to generation 22. The strain T(Y,5)122 has a translocation linking the Y chromosome with the autosome carrying the wp locus. The strain T(Y,3,5)11 has a translocation linking the Y chromosome and the two chromosomes carrying the wp and the dp loci. The egg fertility of the strain T(Y,5)122 was 52% and that of T(Y,3,5)11 was 48%. Larval survival of the latter line was 79%. The technical advantages of these strains was discussed in this paper. The strain T(Y,4)116; T:Y(ap + ), apricot eye, is characterized by wild type males and apricot eye females, as well as apricot eye sterile males. A model explaining the appearance of these ap males is proposed. Isolation and preliminary fertility studies of six sex linked multiple translocations are presented. Each of these strains has three translocations involving the chromosomes Y, 3, 4 and 5. (author). 13 refs, 4 tabs

  19. Growth, development, reproductive competence and adult behaviour of Spodoptera litura (Lepidoptera: Noctuidae) reared on different diets

    International Nuclear Information System (INIS)

    Seth, R.K.; Sharma, V.P.

    2002-01-01

    Spodoptera litura was reared on natural food (castor leaves, Ricinus communis) and on a several semi-synthetic diets using quasi mass rearing techniques. The effect of the different diets and rearing regimes on S. litura growth, development, reproductive competence and adult behaviour was measured. Spodoptera litura reared from a modified chickpea-based diet provided the greatest growth index and index of adequacy. These studies were conducted as a prerequisite for the evaluation of F 1 sterility technique. (author)

  20. Determination of the efficiency of diets for larval development in mass rearing Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Gunathilaka, P A D H N; Uduwawala, U M H U; Udayanga, N W B A L; Ranathunge, R M T B; Amarasinghe, L D; Abeyewickreme, W

    2017-11-23

    Larval diet quality and rearing conditions have a direct and irreversible effect on adult traits. Therefore, the current study was carried out to optimize the larval diet for mass rearing of Aedes aegypti, for Sterile Insect Technique (SIT)-based applications in Sri Lanka. Five batches of 750 first instar larvae (L 1) of Ae. aegypti were exposed to five different concentrations (2-10%) of International Atomic Energy Agency (IAEA) recommended the larval diet. Morphological development parameters of larva, pupa, and adult were detected at 24 h intervals along with selected growth parameters. Each experiment was replicated five times. General Linear Modeling along with Pearson's correlation analysis were used for statistical treatments. Significant differences (P rate and success, sex ratio, adult success, fecundity and hatching rate of Ae. aegypti. The best quality adults can be produced at larval diet concentration of 10%. However, the 8% larval diet concentration was most suitable for adult male survival.

  1. A Programme for the Eradication of the Mediterranean Fruit Fly from Algeria, the Libyan and Arab Jamahiriya, Morocco and Tunisia

    International Nuclear Information System (INIS)

    1993-09-01

    The Mediterranean fruit fly (medfly) is the only fruit fly of economic importance affecting a large number of fruits and vegetables in the Maghreb (Algeria, Libyan Arab Jamahiriya, Morocco and Tunisia). The medfly causes losses of fresh fruit and vegetables in this region of about US $90 million each year. Therefore, eradication of this pest at this time would be very beneficial. Technologies are available to eradicate the medfly which will have no significant negative environmental impacts, and they can be used to accomplish eradication at reasonable cost. This report outlines the procedures available to eradicate the medfly from the Magherb with primary reliance on the use of sterile flies. A large fruit fly rearing facility, of modular design, must be constructed in the Mediterranean Basin and outside the Maghreb to produce and sterilize flies.

  2. Generic Design, Technical Guidelines and Optimal Location of Tsetse Fly Mass-Rearing Facilities. Working Material

    International Nuclear Information System (INIS)

    2004-01-01

    of these AW-IPM based efforts to create T and T free zones. It is, therefore, foreseeable that the demand for good quality sterile tsetse fly males will increase. This is already resulting in proposals to establish additional tsetse fly mass-rearing facilities in Africa. AW-IPM programmes against T and T involving a SIT component will require high investments at an early stage of programme implementation, particularly for the mass-rearing facilities. In order to realize optimum efficacy and efficiency, these programmes must be carefully planned and implemented in a consistent and flexible manner over sufficiently large areas and a rather long time frame. Decisions on the geographic location and design of rearing facilities must be objective, and based on sound assessment criteria. A meeting of expert consultants was convened in Vienna, Austria October 11-15, 2004 under the auspices of FAO/IAEA, in an effort to assist countries in planning the geographic location and in designing large tsetse fly mass-rearing facilities. With regards to assessing the suitability of (proposed) tsetse mass-rearing locations, the meeting identified a number of critical, important and desirable criteria under four (4) main categories, namely Site Characteristics, Climate and Environment, Manpower and Infrastructure and Social and Political supports. A worksheet was developed to summarize scores reached for the identified criteria, in order to ensure that the assessments are objective and verifiable. The meeting also elaborated on the concept of tsetse factory design, based on considerations regarding the involved rooms, their functions, ergonomic flow of the production process and other relevant factors. Required support services were identified and specifics were provided on aspects like controlled environment system design, desired room conditions and occupancy, air filtration and distribution and electricity supply. The consultants' recommendations underline that meeting and this

  3. Studies on mating competitiveness of sterile oriental fruit fly, Bactrocera dorsalis (Hendel)

    International Nuclear Information System (INIS)

    Limohpasmanee, W.; Segsarnviriya, S.

    1998-01-01

    An essential prerequisite for insect control by the sterile insect technique releasing method is mass rearing and sterilizing that do not have adverse effects on longevity and mating behavior of the released males. But many laboratory studies have shown that males irradiated at the completely sterility dose often could not compete with untreated males in mating. This paper studies the effects of gamma radiation at the sterile dose on mating, sexual and sperm competitiveness of the oriental fruit fly, Bactrocera dorsalis (Hendel) under the laboratory condition. It is found that irradiation at the completely sterility dose (90 Gy) had reduced the mating and sperm competition ability of the males. Though the sexual competition was not

  4. A programme for the eradication of the Mediterranean fruit fly from Algeria, the Libyan and Arab Jamahiriya, Morocco and Tunisia

    International Nuclear Information System (INIS)

    1993-09-01

    The Mediterranean fruit fly (medfly) is the only fruit fly of economic importance affecting a large number of fruits and vegetables in the Maghreb (Algeria, Libyan Arab Jamahiriya, Morocco and Tunisia). The medfly causes losses of fresh fruit and vegetables in this region of about US $90 million each year. Therefore, eradication of this pest at this time would be very beneficial. Technologies are available to eradicate the medfly which will have no significant negative environmental impacts, and they can be used to accomplish eradication at reasonable cost. This report outlines the procedures available to eradicate the medfly from the Magherb with primary reliance on the use of sterile flies. A large fruit fly rearing facility, of modular design, must be constructed in the Mediterranean Basin and outside the Maghreb to produce and sterilize flies. Refs, 2 tabs

  5. Application of the sterile-insect technique for control of Mediterranean fruit flies in Israel under field conditions

    International Nuclear Information System (INIS)

    Kamburov, S.S.; Yawetz, A.

    1975-01-01

    A large-scale field experiment, carried out in 1973 in Israel, employing the sterile-insect technique against the Mediterranean fruit fly and conducted over a 10 000 dunam area containing commercial citrus groves, is discussed. The release area was surrounded by a 500-m-wide low-volume (LV) bait spray barrier. Sterile flies were released from the ground and by air twice weekly. Results indicate successful control of the wild fly population for several months only and a clear suppression until July; thereafter, wild fertile females immigrated into the release area through the LV barrier. (author)

  6. IMPROVING MASS REARING TECHNOLOGY FOR SOUTH AMERICAN FRUIT FLY (DIPTERA:TEPHRITIDAE

    Directory of Open Access Journals (Sweden)

    Raimundo Braga Sobrinho

    2006-01-01

    Full Text Available Studies on availability of suitable and economic diets for adults and larvae of the South American fruit fly Anastrepha fraterculus (Wiedemann, 1830 were carried out at the Entomology Unit of the FAO/IAEA Agriculture and Biotechnology Laboratories in Seibersdorf, Austria with the aim to find the best diets to fit in a large scale mass rearing production. The best diet for adult was the combination of Hydrolysate Corn Protein + Yeast Hydrolysate Enzymatic + Sugar (3:1:3. This diet resulted in the highest numbers of egg/female/day, spermatozoid in the spermathecae, percentages of egg hatch, the lowest mortality rate of adults and the highest average mating duration compared with the standard adult diet based on Yeast Hydrolysate Enzymatic + Sugar (1:3. Among eleven larval diets tested, diets based on sugarcane and sugarbeet bagases plus 7% brewer yeast, 8% sugar, 0.2% sodium benzoate, 0.8% of hydrochloric acid and 60% water (adjusted, yielded the highest percentages of egg hatching, pupal recovery, pupal weight and adult emergence. There was no statistical difference with the standard larval diet based on wheat germ 3%, corncob 15%, corn flower 8%, brewer yeast 6%, sugar 8%, sodium benzoate 0.23%, hydrochloric acid 0.63%, nipagin 0.14% and water 59% (adjusted. The significant performance of these adult and larval diets open discussion for future researches on improvement of rearing techniques required for the establishment of sterile insect technique (SIT program focused on the South American fruit fly.

  7. Genetics of the Mediterranean fruit fly in the sterile insect technique

    International Nuclear Information System (INIS)

    Roessler, Y.

    1997-01-01

    Altogether 27 morphological mutations on the five autosomes of the Mediterranean fruit fly, Ceratitis capitata (Wied.), have been isolated and studied in the author's laboratory during 22 years of research on the genetics of this species. Of the 27 loci, 18 were located on chromosomes 4 and 5. No mutant loci were identified on the sex chromosome in the laboratory. Linkage relations, map distances and linear arrangements on the respective chromosomes were established for most of the 27 mutant traits. The wp and dp traits were utilized in the construction of genetic sexing lines in laboratories involved in studies of the sterile insect technique. The occurrence and consequences of male recombination are discussed. (author)

  8. Progress on the artificial rearing of the army worm, Spodoptera (Laphygma) exigua Hb. and radiation sterilization in the male of this species

    International Nuclear Information System (INIS)

    Loaharanu, S.; Chiravathanapong, S.

    1971-01-01

    The army worm, Spodoptera exigua Hb. was reared for 6 more generations in an artificial medium containing Mung bean as a major component. By improving the rearing temperature and humidity conditions, better rearing results were obtained. The average percentage of development from eggs to pupae, from eggs to adults, and from pupae to adults was 41.7+-4.93, 38.44+-6.32 and 88.1+-1.48 respectively. The pupal weight was also calculated. In sterilization studies, the 3-day-old male pupae were subjected to gamma rays at 0, 5 and 10 krads. Upon emerging into adults, they were mated with non-irradiated female moths. Male moths emerged from pupae subjected to 10 krads of gamma rays could significantly induce infertility in eggs deposited

  9. Genetic basis of the sterile insect technique

    International Nuclear Information System (INIS)

    Robinson, A.S.

    2014-01-01

    The use of the sterile insect technique for insect control relies on the introduction of sterility in the females of the wild population. This sterility is produced following the mating of these females with released males carrying, in their sperm, dominant lethal mutations that have been induced by ionizing radiation. As well as radiation-induced sterility, natural mechanisms can be recruited, especially the use of hybrid sterility. Radiation is usually one of the last procedures that insects undergo before leaving mass-rearing facilities for release in the field. It is essential that the dosimetry of the radiation source be checked to ensure that all the insects receive the required minimum dose. A dose should be chosen that maximizes the level of introduced sterility in the wild females in the field. Irradiation in nitrogen can provide protection against the detrimental somatic effects of radiation. Currently, the development of molecular methods to sterilize pest insects in the field, by the release of fertile insects carrying trans genes, is very much in vogue. It is concluded that using a physical process, such as radiation, will always have significant advantages over genetic and other methods of sterilization for the large-scale application of the sterile insect technique. (author)

  10. Colonisation and mass rearing: learning from others

    Directory of Open Access Journals (Sweden)

    Howell Paul I

    2009-11-01

    Full Text Available Abstract Mosquitoes, just as other insects produced for the sterile insect technique (SIT, are subjected to several unnatural processes including laboratory colonisation and large-scale factory production. After these processes, sterile male mosquitoes must perform the natural task of locating and mating with wild females. Therefore, the colonisation and production processes must preserve characters necessary for these functions. Fortunately, in contrast to natural selection which favours a suite of characteristics that improve overall fitness, colonisation and production practices for SIT strive to maximize only the few qualities that are necessary to effectively control populations. However, there is considerable uncertainty about some of the appropriate characteristics due to the lack of data. Development of biological products for other applications suggest that it is possible to identify and modify competitiveness characteristics in order to produce competitive mass produced sterile mosquitoes. This goal has been pursued - and sometimes achieved - by mosquito colonisation, production, and studies that have linked these characteristics to field performance. Parallels are drawn to studies in other insect SIT programmes and aquaculture which serve as vital technical reference points for mass-production of mosquitoes, most of whose development occurs - and characteristics of which are determined - in an aquatic environment. Poorly understood areas that require further study are numerous: diet, mass handling and genetic and physiological factors that influence mating competitiveness. Compromises in such traits due to demands to increase numbers or reduce costs, should be carefully considered in light of the desired field performance.

  11. Quality Control for Expanded Tsetse Production, Sterilization and Field Application

    International Nuclear Information System (INIS)

    2012-07-01

    The use of the sterile insect technique (SIT) for the control of pest insects as part of an integrated, area-wide approach is widely accepted. Its application for the eradication of different tsetse flies, the vectors of human sleeping sickness and African animal trypanosomosis, is attracting increasing interest. Following several initial demonstrations of the application of the SIT for tsetse control the technique was applied on the island of Unguja, Zanzibar, in the mid-1990s and, as the final component of an integrated control programme, led to the eradication of the only tsetse species on the island, Glossina austeni. This successful programme encouraged a number of countries to embark on projects with an SIT component for tsetse control, most Ethiopia. In 2001 the Pan African Tsetse and Trypanosomosis Eradication Campaign (PATTEC) was launched by the Organization of African Unity (now African Union, AU) and, subsequently, six countries obtained funding from the African Development Bank (AfDB) in 2005 to support control programmes with an SIT component. A further six countries have subsequently requested AfDB funding for their programmes. The FAO/IAEA coordinated research project (CRP) on Automation for Tsetse Mass Rearing For Use in Sterile Insect Technique Programmes, which was completed in 2001, led to the development of a semi-automated system for tsetse production. Using this new system, a large rearing facility was established in Addis Ababa, Ethiopia, to supply sterile males for an elimination programme in the southern Rift Valley. The development of large-scale rearing highlighted the need for improved quality control procedures and, with this in mind, the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture established a CRP in 2003 entitled Improved and Harmonized Quality Control for Expanded Tsetse Production, Sterilization and Field Application with the Objective of Improving and Expanding the Quality Control Sections of the FAO

  12. Quality Control for Expanded Tsetse Production, Sterilization and Field Application

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-15

    The use of the sterile insect technique (SIT) for the control of pest insects as part of an integrated, area-wide approach is widely accepted. Its application for the eradication of different tsetse flies, the vectors of human sleeping sickness and African animal trypanosomosis, is attracting increasing interest. Following several initial demonstrations of the application of the SIT for tsetse control the technique was applied on the island of Unguja, Zanzibar, in the mid-1990s and, as the final component of an integrated control programme, led to the eradication of the only tsetse species on the island, Glossina austeni. This successful programme encouraged a number of countries to embark on projects with an SIT component for tsetse control, most Ethiopia. In 2001 the Pan African Tsetse and Trypanosomosis Eradication Campaign (PATTEC) was launched by the Organization of African Unity (now African Union, AU) and, subsequently, six countries obtained funding from the African Development Bank (AfDB) in 2005 to support control programmes with an SIT component. A further six countries have subsequently requested AfDB funding for their programmes. The FAO/IAEA coordinated research project (CRP) on Automation for Tsetse Mass Rearing For Use in Sterile Insect Technique Programmes, which was completed in 2001, led to the development of a semi-automated system for tsetse production. Using this new system, a large rearing facility was established in Addis Ababa, Ethiopia, to supply sterile males for an elimination programme in the southern Rift Valley. The development of large-scale rearing highlighted the need for improved quality control procedures and, with this in mind, the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture established a CRP in 2003 entitled Improved and Harmonized Quality Control for Expanded Tsetse Production, Sterilization and Field Application with the Objective of Improving and Expanding the Quality Control Sections of the FAO

  13. Applying the sterile insect technique to the control of insect pests

    International Nuclear Information System (INIS)

    LaChance, L.E.; Klassen, W.

    1991-01-01

    The sterile insect technique involves the mass-rearing of insects, which are sterilized by gamma rays from a 60 Co source before being released in a controlled fashion into nature. Matings between the sterile insects released and native insects produce no progeny, and so if enough of these matings occur the pest population can be controlled or even eradicated. A modification of the technique, especially suitable for the suppression of the moths and butterflies, is called the F, or inherited sterility method. In this, lower radiation doses are used such that the released males are only partially sterile (30-60%) and the females are fully sterile. When released males mate with native females some progeny are produced, but they are completely sterile. Thus, full expression of the sterility is delayed by one generation. This article describes the use of the sterile insect technique in controlling the screwworm fly, the tsetse fly, the medfly, the pink bollworm and the melon fly, and of the F 1 sterility method in the eradication of local gypsy moth infestations. 18 refs, 5 figs, 1 tab

  14. Vitality Improvement of the Mediterranean Fruit Fly, Ceratitis capitata Wied 2- Measured by using ME and At Pase Enzyme Activities and Total Protein Content

    International Nuclear Information System (INIS)

    Salama, M.S.; Shoman, A.A.; Elbermawy, S.M.; Abul Yazid, I.

    2000-01-01

    The present investigation aims at producing sterile adult Mediterranean fruit fly, Ceratitis capitata Wied. Having the best possible vitality through the use of irradiation and /or a mutagenic substances to be used in a sterile insect technique program. Several types of mutagenic that were thought to cause mutations were used as IGR's, temperature, formaldehyde, colchicine, alcohols, serve ral types of larval rearing media and gamma-rays. In a common pathway, malic enzyme (ME) activity, adenosine triphosphatase (ATPase) enzyme activity and the total protein contents are studied as direct parameters for measuring vitality of the insect. It was found that there is an increment at levels of these parameters due to the treatment of egg stage by the previously mentioned treatments specially the usage of the rice hulls as a bulking component in the larval rearing media alone or followed by irradiation of the pupal stage with 90 Gy

  15. Quality of mass-reared codling moth (Lepidoptera: Tortricidae) after long-distance transportation: 1. Logistics of shipping procedures and quality parameters as measured in the laboratory.

    Science.gov (United States)

    Blomefield, T; Carpenter, J E; Vreysen, M J B

    2011-06-01

    The sterile insect technique (SIT) is a proven effective control tactic against lepidopteran pests when applied in an areawide integrated pest management program. The construction of insect mass-rearing facilities requires considerable investment and moth control strategies that include the use of sterile insects could be made more cost-effective through the importation of sterile moths produced in other production centers. For codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), this is an attractive option because mating studies have confirmed the absence of mating barriers between codling moth populations from geographically different areas. To assess the feasibility of long-distance transportation of codling moths, pupae and adult moths were transported in 2004 from Canada to South Africa in four shipments by using normal commercial transport routes. The total transport time remained below 67 h in three of the consignments, but it was 89 h in the fourth consignment. Temperature in the shipping boxes was fairly constant and remained between -0.61 and 0.16 degrees C for 76.8-85.7% of the time. The data presented indicate that transporting codling moths as adults and pupae from Canada to South Africa had little effect on moth emergence, longevity, and ability to mate, as assessed in the laboratory. These results provide support to the suggestion that the STT for codling moth in pome fruit production areas might be evaluated and implemented by the importation of irradiated moths from rearing facilities in a different country or hemisphere.

  16. More is different: Reconciling eV sterile neutrinos with cosmological mass bounds

    Directory of Open Access Journals (Sweden)

    Yong Tang

    2015-11-01

    Full Text Available It is generally expected that adding light sterile species would increase the effective number of neutrinos, Neff. In this paper we discuss a scenario that Neff can actually decrease due to the neutrino oscillation effect if sterile neutrinos have self-interactions. We specifically focus on the eV mass range, as suggested by the neutrino anomalies. With large self-interactions, sterile neutrinos are not fully thermalized in the early Universe because of the suppressed effective mixing angle or matter effect. As the Universe cools down, flavor equilibrium between active and sterile species can be reached after big bang nucleosynthesis (BBN epoch, but leading to a decrease of Neff. In such a scenario, we also show that the conflict with cosmological mass bounds on the additional sterile neutrinos can be relaxed further when more light species are introduced. To be consistent with the latest Planck results, at least 3 sterile species are needed.

  17. Madeira-Med, a sterile insect technique programme for control of the Mediterranean fruit fly in Madeira, Portugal

    International Nuclear Information System (INIS)

    Pereira, R.; Barbosa, A.; Silva, N.; Caldeira, J.; Dantas, L.; Pacheco, J.

    2000-01-01

    The islands of Madeira are located 980 km west-southwest from mainland Portugal and have a population of approximately 255,000. The islands are volcanic with very little level land suitable for large agricultural production. Approximately 47% of the land area is above 700 m. Thus the area likely to require Medfly control is about half of the islands. Agricultural production is on small scale, frequently part-time and mostly terraced because of the volcanic nature of the land. Grapes for wine and bananas are the predominant fruit crops. Neither are primary Medfly hosts. Citrus and tropical fruits are not produced in large quantities and are generally not of high quality. This is, to a large extent, because intensive Mediterranean fruit fly (Medfly), Ceratitis capitata (Wied.), attack has prevented the establishment of citrus and tropical fruit production. Medflies are present the year round on land below 300 m, resulting in the necessity of continuous control measures, usually insecticide bait sprays. Current annual losses from the Medflies in Madeira are estimated at US$3 million. In 1992, the agricultural officials of Madeira applied for an European Union (EU) grant to eliminate the Medfly from Madeira using the sterile insect technique (SIT). After extensive discussions, the project was changed from eradication to control and approved in late 1993 with EU support of about 8 million ECU over a 7-year period. Subsequently, the Madeira officials applied for, and received, a technical assistance project from the International Atomic Energy Agency (IAEA). The IAEA support is primarily for training and consultant services. Sterile female Medflies puncture fruits when they try to lay eggs. These punctures, called 'sterile stings', result in a reduced crop value. For this reason, the Madeira-Med programme will use only sterile male Medflies in its SIT programme. This not only eliminates the sterile sting problem but also increases the efficacy of the sterile males from

  18. Study of the compatibility and competitiveness of sterile males in the framework of the struggle by the sterile insect technique against the Ceratitis

    International Nuclear Information System (INIS)

    Azzabi, Jihene

    2007-01-01

    We evaluated under semi-natural field-cage conditions sexual compatibility and competitivity of laboratory strain (Genetic Sexing Strain GSS) ''Vienna 8''. The GSS strain is produced under mass (rearing conditions at the facility of production of sterile males at Sidi Thabat. Wild flies were obtained from infested Sommer oranges. Twenty-five wild males, 25 wild females and 25 GSS were released into cage and mating pairs collected. The determination of indices such as the Isolation Index (ISI), the Male Relative Index (MRPI), the Stalker Index (I) and the Relative Sterile Index (RSI) shows that there is no compatibility and competitiveness between the two strains with a tendency to behaviour of sexual isolation. Sterile male tests dissection irradiated at the dose of (0 Gy, 110 Gy, 120 Gy, 130 Gy and 145 Gy) and correspondent female spermatic show the important damage of the irradiation on the cells but decrease the quality of the sterile male (mating duration, sperm transfer.). (Author)

  19. Quality control tests of lab-reared Cydia pomonella and Cactoblastis cactorum field performance: Comparison of laboratory and field bioassays.

    Science.gov (United States)

    Research, operational, and commercial programs which rely on mass-reared insects of high quality and performance, need accurate methods for monitoring quality degradation during each step of production, handling and release. With continued interest in the use of the sterile insect technique (SIT) a...

  20. Flight Muscle Development in the Males of Glossina Pallidipes Reared for the Sterile Insect Technique

    Energy Technology Data Exchange (ETDEWEB)

    Ciampor, F Jr; Palosova, Z; Mancosova, L; Takac, P [Institute of Zoology, Slovak Academy of Sciences, Bratislava, SK-845 06 (Slovakia)

    2012-07-15

    The project's main goal was to study the influence of laboratory conditions on the development of flight muscles and the ability to fly in males of Glossina pallidipes Austen. Flight muscles can serve as an important criterion in the quality control of mass reared tsetse flies. All experiments were performed in the research and training facility in Bratislava which provided the flies. The experiments were generally performed by comparing different age groups and groups with different flight activity. To acquire data, several approaches were employed, i.e. classical measurements (residual dry weight, thoracic surface) as well as other alternatives - flight mill, electron microscopy and immunohistochemistry - to visualize and analyse muscle development. The results clearly identified differences in age groups. Slight changes in the development of flight muscles regarding different chances to fly were also detected, but these were not sufficiently significant to decrease the quality of males produced in mass rearing facilities. No distinct trends (rising or declining of amount of metabolites) in the groups studied were detected. The differences were in the amount of analysed metabolic components and the structure of the flight muscles. Our results suggest that, similar to other Glossina species, in G. pallidipes males the first days after emergence are crucial for successful muscle development. On the other hand, rearing in cages does not negatively influence the quality of males with respect to their ability to fly and actively search for females in the wild after release. We also compared the mating behaviour of irradiated and non-irradiated males. We initiated the development of a functional walk-in field cage in which to rear a small colony of G. pallidipes under semi-natural conditions. Our work suggested that outside climatic conditions and suitable cage components, e.g. food source, limit the successful realization of using such a cage for rearing tsetse flies

  1. Sterile neutrinos with eV masses in cosmology — How disfavoured exactly?

    International Nuclear Information System (INIS)

    Hamann, Jan; Hannestad, Steen; Raffelt, Georg G.; Wong, Yvonne Y.Y.

    2011-01-01

    We study cosmological models that contain sterile neutrinos with eV-range masses as suggested by reactor and short-baseline oscillation data. We confront these models with both precision cosmological data (probing the CMB decoupling epoch) and light-element abundances (probing the BBN epoch). In the minimal ΛCDM model, such sterile neutrinos are strongly disfavoured by current data because they contribute too much hot dark matter. However, if the cosmological framework is extended to include also additional relativistic degrees of freedom beyond the three standard neutrinos and the putative sterile neutrinos, then the hot dark matter constraint on the sterile states is considerably relaxed. A further improvement is achieved by allowing a dark energy equation of state parameter w e degeneracy. Any model containing eV-mass sterile neutrinos implies also strong modifications of other cosmological parameters. Notably, the inferred cold dark matter density can shift up by 20–75% relative to the standard ΛCDM value

  2. Rearing of germfree chicks in a vinyl isolator

    International Nuclear Information System (INIS)

    Ishibashi, Teru; Kametaka, Masao; Ozaki, Akira; Yamamoto, Tetsuzo; Kaneuchi, Choji.

    1977-01-01

    A method of rearing germfree chicks in a vinyl isolator was developed, Hatchability of eggs was higher than 95% when eggs were sterilized in a 1.5% mercuric chloride solution on the 2nd day before hatching. Sterility was 93% when 5 to 10 chicks were reared in a vinyl isolator for 2 weeks. Depression of body weight gain was observed in chicks fed diet irradiated at higher than 4 Mrad. However, no effects of irradiation on chick growth were observed when fat and the other components were sterilized separately and mixed before feeding. The growth rates of germfree chicks were higher than those of the conventional chicks which were supplied a diluted solution of fresh cecum feces of young hens with a normal intestinal flora pattern at the first feeding. (auth.)

  3. Global warming and mass mortalities of benthic invertebrates in the Mediterranean Sea.

    Directory of Open Access Journals (Sweden)

    Irene Rivetti

    Full Text Available Satellite data show a steady increase, in the last decades, of the surface temperature (upper few millimetres of the water surface of the Mediterranean Sea. Reports of mass mortalities of benthic marine invertebrates increased in the same period. Some local studies interpreted the two phenomena in a cause-effect fashion. However, a basin-wide picture of temperature changes combined with a systematic assessment on invertebrate mass mortalities was still lacking. Both the thermal structure of the water column in the Mediterranean Sea over the period 1945-2011 and all documented invertebrate mass mortality events in the basin are analysed to ascertain if: 1- documented mass mortalities occurred under conditions of positive temperature trends at basin scale, and 2- atypical thermal conditions were registered at the smaller spatial and temporal scale of mass mortality events. The thermal structure of the shallow water column over the last 67 years was reconstructed using data from three public sources: MEDAR-MEDATLAS, World Ocean Database, MFS-VOS programme. A review of the mass mortality events of benthic invertebrates at Mediterranean scale was also carried out. The analysis of in situ temperature profiles shows that the Mediterranean Sea changed in a non-homogeneous fashion. The frequency of mass mortalities is increasing. The areas subjected to these events correspond to positive thermal anomalies. Statistically significant temperature trends in the upper layers of the Mediterranean Sea show an increase of up to 0.07°C/yr for a large fraction of the basin. Mass mortalities are consistent with both the temperature increase at basin scale and the thermal changes at local scale, up to 5.2°C. Our research supports the existence of a causal link between positive thermal anomalies and observed invertebrate mass mortalities in the Mediterranean Sea, invoking focused mitigation initiatives in sensitive areas.

  4. Global Warming and Mass Mortalities of Benthic Invertebrates in the Mediterranean Sea

    Science.gov (United States)

    Rivetti, Irene; Fraschetti, Simonetta; Lionello, Piero; Zambianchi, Enrico; Boero, Ferdinando

    2014-01-01

    Satellite data show a steady increase, in the last decades, of the surface temperature (upper few millimetres of the water surface) of the Mediterranean Sea. Reports of mass mortalities of benthic marine invertebrates increased in the same period. Some local studies interpreted the two phenomena in a cause-effect fashion. However, a basin-wide picture of temperature changes combined with a systematic assessment on invertebrate mass mortalities was still lacking. Both the thermal structure of the water column in the Mediterranean Sea over the period 1945–2011 and all documented invertebrate mass mortality events in the basin are analysed to ascertain if: 1- documented mass mortalities occurred under conditions of positive temperature trends at basin scale, and 2- atypical thermal conditions were registered at the smaller spatial and temporal scale of mass mortality events. The thermal structure of the shallow water column over the last 67 years was reconstructed using data from three public sources: MEDAR-MEDATLAS, World Ocean Database, MFS-VOS programme. A review of the mass mortality events of benthic invertebrates at Mediterranean scale was also carried out. The analysis of in situ temperature profiles shows that the Mediterranean Sea changed in a non-homogeneous fashion. The frequency of mass mortalities is increasing. The areas subjected to these events correspond to positive thermal anomalies. Statistically significant temperature trends in the upper layers of the Mediterranean Sea show an increase of up to 0.07°C/yr for a large fraction of the basin. Mass mortalities are consistent with both the temperature increase at basin scale and the thermal changes at local scale, up to 5.2°C. Our research supports the existence of a causal link between positive thermal anomalies and observed invertebrate mass mortalities in the Mediterranean Sea, invoking focused mitigation initiatives in sensitive areas. PMID:25535973

  5. A Programme for the Eradication of the Mediterranean Fruit Fly from Algeria, the Libyan and Arab Jamahiriya, Morocco and Tunisia; Programme d'eradication de la mouche mediterraneenne des fruits en Algerie, en Jamahiriya Arabe Libyenne, au Maroc et en Tunisie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-09-15

    The Mediterranean fruit fly (medfly) is the only fruit fly of economic importance affecting a large number of fruits and vegetables in the Maghreb (Algeria, Libyan Arab Jamahiriya, Morocco and Tunisia). The medfly causes losses of fresh fruit and vegetables in this region of about US $90 million each year. Therefore, eradication of this pest at this time would be very beneficial. Technologies are available to eradicate the medfly which will have no significant negative environmental impacts, and they can be used to accomplish eradication at reasonable cost. This report outlines the procedures available to eradicate the medfly from the Magherb with primary reliance on the use of sterile flies. A large fruit fly rearing facility, of modular design, must be constructed in the Mediterranean Basin and outside the Maghreb to produce and sterilize flies.

  6. Pink bollworm integrated management using sterile insects under field trial conditions, Imperial Valley, California

    International Nuclear Information System (INIS)

    Walters, M.L.; Staten, R.T.; Roberson, R.C.

    2000-01-01

    The pink bollworm moth (Pectinophora gossypiella Saunders) feeds almost exclusively on cotton (Gossypium spp.) and causes economic loss (Pfadt 1978). The pink bollworm (PBW) is often the key pest of cotton in Arizona, southern California, and northwestern Mexico. The larvae (immature stages) bore into the developing cotton fruit, where they feed on the cotton lint and seeds, causing significant damage and dramatically reducing the yield of cotton lint (Pfadt 1978). The PBW is difficult to control with conventional means (insecticides) because it spends the destructive larval phase inside the cotton boll where it is well protected from control measures. Cultural controls, such as a short growing season, have successfully decreased the population in the Imperial Valley (Chu et al. 1992) to the point where eradication may be possible using sterile insects and genetically engineered cotton. Because the PBW is an introduced insect, with few plant hosts other than cultivated cotton, its eradication from continental USA is a desirable and economically attractive alternative to the continued use of pesticides and/or further loss to the pest. Mass releases of sterile insects began in earnest in 1970 in the San Joaquin Valley, California, in order to inhibit normal reproduction and to eradicate the pest in an environmentally responsible manner. Sterile release involves mass production and sexual sterilisation using irradiation (20 krad for PBW adults). This was accomplished by building a rearing facility in Phoenix, AZ. The facility has 6,410 square metres of permanent laboratories, rearing and irradiation chambers and insect packing rooms. The facility operates the year round but with a variable production rate, that is, maximal during the cotton growing season (May through September). Sterile insect technology is based on the monitoring of the native and sterile populations in the field and the subsequent release of appropriate numbers of sterile insects in order to

  7. CONSTRUCTION AND REARING OF THE MEDITERRANEAN FRUIT FLY, CERATITIS CAPITATA, GENETIC SEXING STRAINS, VIENNA-8 WITH MALES CARRYING THE MARKER SERGEANT-2 (VIENNA-8/Sr2)

    International Nuclear Information System (INIS)

    SHOMAN, A.A.

    2008-01-01

    A trial on the construction, maintenance and adaptation of the genetic sexing strain Vienna-8/Sr2 of the Mediterranean fruit fly, Ceratitis capitata (Wied.), has been done in the fruit fly laboratories of the Egyptian Atomic Energy Authority (EAEA) in the cooperation with the laboratories of International Atomic Energy Agency, Vienna. This trial was successful and this strain was maintained in the medfly laboratories of the EAEA for more than 10 generations up till now. Vienna-8/ Sr 2 is very stable strain and carries the dominant mutation called sergeant-2 (Sr 2 ) and could be used as a visible marker for the sterile male flies released in the field for controlling the Mediterranean fruit fly. This visible marker simplifies the discrimination between released sterile males and wild males caught in field monitoring traps. Males of this strain have three white stripes on the abdomen while wild males have only two stripes. The use of this genetic marker, as a replacement of the external dye marker, clearly has an immediate positive impact on the efficiency of Mediterranean fruit fly SIT programs (by using gamma radiation)

  8. Dipping of Eggs, Use of Low Temperature and Aeration to Improve Fruit Fly Bactrocera Carambolae (Drew and Hancock) Mass Rearing in Sterile Insect Technique Programme

    International Nuclear Information System (INIS)

    Nasution, Indah Arastuti; Achmad Nasroh Kuswadi

    2004-01-01

    In the Sterile Insect Technique (SIT) programme a large number of homogenous age of pupae should be produced to be sterilized and released into the field. A methodology to preserve eggs which at the same time delay the egg hatch is needed in the production of a large number of pupae with homogenous age. The study on method of preserving fruit fly eggs the effect of dipping, low temperature, on the viability of eggs, the quality of larvae hatched from the eggs, and the quality of pupae produced were observed. Viability of eggs were observed as percent of egg hatch, quality of larvae as number of pupae produced from 0.5 ml of eggs when reared on artificial diet, and quality of pupae as percent of the flies number emerged and flew from the pupae. In room temperature (26 o C) dipping did not preserve fruit fly eggs and aeration did not improve the preservation. Although after one day dipping the viability of eggs only decreased from 90 % (control) to 80.5 %, (without aeration) and 81.5 % (with aeration) it decreased the number of pupae been produced from 1447 pupae (control) to 382 pupae (without aeration) and 616 pupae (with aeration). Low temperature successfully preserved the egg up to 24 hours. After 24 hour dipping in low temperature (16 o C) the viability of eggs were decreased up to 84.75 % (without aeration) and able to produce 1104 pupae. Aeration during dipping in low temperature did not improve the preservation. (author)

  9. Rearing the Fruit Fly Drosophila melanogaster Under Axenic and Gnotobiotic Conditions.

    Science.gov (United States)

    Koyle, Melinda L; Veloz, Madeline; Judd, Alec M; Wong, Adam C-N; Newell, Peter D; Douglas, Angela E; Chaston, John M

    2016-07-30

    The influence of microbes on myriad animal traits and behaviors has been increasingly recognized in recent years. The fruit fly Drosophila melanogaster is a model for understanding microbial interactions with animal hosts, facilitated by approaches to rear large sample sizes of Drosophila under microorganism-free (axenic) conditions, or with defined microbial communities (gnotobiotic). This work outlines a method for collection of Drosophila embryos, hypochlorite dechorionation and sterilization, and transfer to sterile diet. Sterilized embryos are transferred to sterile diet in 50 ml centrifuge tubes, and developing larvae and adults remain free of any exogenous microbes until the vials are opened. Alternatively, flies with a defined microbiota can be reared by inoculating sterile diet and embryos with microbial species of interest. We describe the introduction of 4 bacterial species to establish a representative gnotobiotic microbiota in Drosophila. Finally, we describe approaches for confirming bacterial community composition, including testing if axenic Drosophila remain bacteria-free into adulthood.

  10. Sterile neutrinos with eV masses in cosmology — How disfavoured exactly?

    DEFF Research Database (Denmark)

    Hamann, Jan; Hannestad, Steen; Raffelt, G.G.

    2011-01-01

    We study cosmological models that contain sterile neutrinos with eV-range masses as suggested by reactor and short-baseline oscillation data. We confront these models with both precision cosmological data (probing the CMB decoupling epoch) and light-element abundances (probing the BBN epoch...... be circumvented by a small νe degeneracy. Any model containing eV-mass sterile neutrinos implies also strong modifications of other cosmological parameters. Notably, the inferred cold dark matter density can shift up by 20-75% relative to the standard ΛCDM value....

  11. Bioaccumulation of mercury in reared and wild Ruditapes philippinarum of a Mediterranean lagoon

    Science.gov (United States)

    Giani, Michele; Rampazzo, Federico; Berto, Daniela; Maggi, Chiara; Mao, Andrea; Horvat, Milena; Emili, Andrea; Covelli, Stefano

    2012-11-01

    The Marano and Grado lagoon, one of the largest wetlands in the Mediterranean Sea, has been subject to mercury contamination by industrial and mining activities. This must be considered a severe threat for Manila clam harvesting, which is an important fishing and commercial activity in the area. Contamination levels and potential risk for human consumption both in reared and wild clams collected from the lagoon were assessed by analyzing total mercury (THg) and methylmercury (MeHg) contents. In addition, relationships between THg and MeHg in sediments and in the bivalves were investigated. Increased bioaccumulation of THg but not of MeHg with increasing size of wild clam populations was observed at most sites. Higher concentrations both of THg (605 ± 210 ng g-1 ww) and MeHg (147 ± 37 ng g-1 ww) were detected in the eastern lagoon where the highest THg contents in sediments were observed as a consequence of the long-term supply of cinnabar rich suspended material from the Isonzo river. The variation of Hg content in seeded Manila clams during growth was monitored over a period of 18 months at two sites of the western sector of the lagoon. Results showed that the two areas were suitable for clam farming, with THg levels in reared bivalves always lower than the 0.5 mg kg-1 ww European Community limit. At the same time, as clams grew bigger in size, their THg and MeHg concentrations decreased, becoming lower than in the starting seeded pool. Reared clams presented lower THg (84 ± 55 ng g-1 ww) and MeHg (44.1 ± 24.6 ng g-1 ww) content than wild clams of the same commercial size (>30 mm). Based on a precautionary approach, intake of Hg and MeHg with the estimated clam consumption does not seem to constitute a risk for human health in the studied area.

  12. LSND versus MiniBooNE: Sterile neutrinos with energy dependent masses and mixing?

    CERN Document Server

    Schwetz, Thomas

    2008-01-01

    Standard active-sterile neutrino oscillations do not provide a satisfactory description of the LSND evidence for neutrino oscillations together with the constraints from MiniBooNE and other null-result short-baseline oscillation experiments. However, if the mass or the mixing of the sterile neutrino depends in an exotic way on its energy all data become consistent. I explore the phenomenological consequences of the assumption that either the mass or the mixing scales with the neutrino energy as $1/E_\

  13. Breakfast of champions or kiss of death? Survival and sexual performance of protein-fed, sterile Mediterranean fruit flies (Diptera: Tephritidae)

    International Nuclear Information System (INIS)

    Yuval, B.; Maor, M.; Levy, K.; Kaspi, R.; Taylor, P.; Shelly, T.

    2007-01-01

    The sterile insect technique (SIT) is increasingly being used around the world to control Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), the Mediterranean fruit fly as part of an area-wide integrated approach. One option that may improve the effectiveness of the SIT, by increasing the sexual competitiveness of released sterile males, consists of feeding males protein during the post-teneral stage, a diet that increases sexual performance of wild males. We examine the effects of diet on the successive hurdles males must overcome in order to inseminate females, i.e., joining leks, copulating females, having their sperm stored and inhibition of female remating. In addition, we address the effects of diet on post-release foraging success, longevity, and the ability to withstand starvation. While protein feeding universally increases the sexual success of wild males, its effect on sterile males varies with strain, experimental settings, and environmental conditions. In some cases, treatments that resulted in the best sexual performance were significantly associated with increased vulnerability to starvation. However, no particular diet affected the ability of sterile males to find nutrients in the field when these where available. We suggest it may be better to release relatively short-lived flies that are highly competitive, rather than long-lived, sexually ineffective ones. (author) [es

  14. Role of population and behavioural ecology in the sterile insect technique

    International Nuclear Information System (INIS)

    Ito, Y.; Yamamura, K.

    2005-01-01

    The principles of population and behavioural ecology in relation to the application of the sterile insect technique (SIT) for eradication of a pest are explained. These include: (1) a logistic population model for estimation of the population fluctuation of target animals and the number of sterile males to be released for successful eradication, (2) mark-recapture estimations of density and mortality rate of the target population, especially for remote areas, where repeated releases and recaptures are difficult, (3) models of dispersal to assess dispersal distance of target animals, and (4) equations for estimating the decrease of sexual competitiveness of mass-reared strains under field conditions. The method to estimate dispersal distance curves when attraction areas of traps are overlapping, and changes in mate-choice of wild females resulting from inadvertent selection when the SIT is applied, are explained. The necessity of field estimation of sexual competitiveness of released sterile males is also emphasized. (author)

  15. Improving the sterile sperm identification method for its implementation in the area-wide sterile insect technique program against Ceratitis capitata (Diptera: Tephritidae) in Spain

    International Nuclear Information System (INIS)

    Juan-Blasco, M.; Urbaneja, A.; San Andrés, V.; Sabater-Muñoz, B.; Castañera, P.

    2014-01-01

    The success of sterile males in area-wide sterile insect technique (aw-SIT) programs against Ceratitis capitata (Wiedemann) is currently measured by using indirect methods as the wild: sterile male ratio captured in monitoring traps. In the past decade, molecular techniques have been used to improve these methods. The development of a polymerase chain reaction-restriction fragment-length polymorphism- based method to identify the transfer of sterile sperm to wild females, the target of SIT, was considered a significant step in this direction. This method relies on identification of sperm by detecting the presence of Y chromosomes in spermathecae DNA extract complemented by the identification of the genetic origin of this sperm: Vienna-8 males or wild haplotype. However, the application of this protocol to aw-SIT programs is limited by handling time and personnel cost. The objective of this work was to obtain a high-throughput protocol to facilitate the routine measurement in a pest population of sterile sperm presence in wild females. The polymerase chain reactionrestriction fragment-length polymorphism markers previously developed were validated in Mediterranean fruit by samples collected from various locations worldwide. A laboratory protocol previously published was modified to allow for the analysis of more samples at the same time. Preservation methods and preservation times commonly used for Mediterranean fruit by female samples were assessed for their influence on the correct molecular detection of sterile sperm. This high-throughput methodology, as well as the results of sample management presented here, provide a robust, efficient, fast, and economical sterile sperm identification method ready to be used in all Mediterranean fruit by SIT programs. (author)

  16. Cosmology favoring extra radiation and sub-eV mass sterile neutrinos as an option.

    Science.gov (United States)

    Hamann, Jan; Hannestad, Steen; Raffelt, Georg G; Tamborra, Irene; Wong, Yvonne Y Y

    2010-10-29

    Precision cosmology and big-bang nucleosynthesis mildly favor extra radiation in the Universe beyond photons and ordinary neutrinos, lending support to the existence of low-mass sterile neutrinos. We use the WMAP 7-year data, small-scale cosmic microwave background observations from ACBAR, BICEP, and QuAD, the SDSS 7th data release, and measurement of the Hubble parameter from HST observations to derive credible regions for the assumed common mass scale m{s} and effective number N{s} of thermally excited sterile neutrino states. Our results are compatible with the existence of one or perhaps two sterile neutrinos, as suggested by LSND and MiniBooNE, if m{s} is in the sub-eV range.

  17. Economic evaluation of damage caused by, and methods of control of, the Mediterranean fruit fly in the Maghreb. An analysis covering three control options, including the sterile insect technique. Report of an expert group

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    Fruit and vegetable production is an important agricultural sector throughout the Mediterranean Basin, which is dependent on aerial or ground insecticide applications to protect commercial crops against the Mediterranean fruit fly. Pesticide applications are required up to twelve times a year, costing large sums of money. This study assesses for the four North African countries the economics of different pest control/eradication alternatives: insecticide application and the more environmentally friendly alternatives based on the Sterile Insect Technique. It is concluded that Sterile Insect Technique, not only very attractive from environmental point of view, but is also a feasible option from economic point of view. 40 refs, 3 figs, 37 tabs.

  18. Economic evaluation of damage caused by, and methods of control of, the Mediterranean fruit fly in the Maghreb. An analysis covering three control options, including the sterile insect technique. Report of an expert group

    International Nuclear Information System (INIS)

    1995-10-01

    Fruit and vegetable production is an important agricultural sector throughout the Mediterranean Basin, which is dependent on aerial or ground insecticide applications to protect commercial crops against the Mediterranean fruit fly. Pesticide applications are required up to twelve times a year, costing large sums of money. This study assesses for the four North African countries the economics of different pest control/eradication alternatives: insecticide application and the more environmentally friendly alternatives based on the Sterile Insect Technique. It is concluded that Sterile Insect Technique, not only very attractive from environmental point of view, but is also a feasible option from economic point of view. 40 refs, 3 figs, 37 tabs

  19. Demographic and quality control parameters of Anastrepha Fraterculus (Diptera: Tephritidae) maintained under artificial rearing

    International Nuclear Information System (INIS)

    Vera, T.; Abraham, S.; Oviedo, A.; Willink, E.

    2007-01-01

    The integration of the sterile insect technique (SIT) in the management of the South American fruit fly Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) is a promising alternative to chemically-based control in those areas where it is sympatric with Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) or other tephritid species for which the SIT is being used. Implementation of the SIT requires the development of a cost effective mass-rearing protocol. In this work, we present demographic and quality control parameters for the A. fraterculus strain reared at the Estacion Experimental Agroindustrial Obispo Colombres, Tucuman, Argentina. Considering the rearing cage as the reproduction unit, we observed that fecundity is optimal during the first 3 weeks after the onset of oviposition. Fertility was constant during this period. During 2003 and 2004, some improvements were made to the existing rearing protocol, which resulted in increased larval viability, pupal weight, and adult emergence. Current weekly egg production is 1 million per week. These eggs are used to maintain the colony and to assess quality parameters. Finally, research needs leading to improved yields and fly quality are discussed. (author) [es

  20. Long distance transport of irradiated male Glossina palpalis gambiensis pupae and its impact on sterile male yield

    International Nuclear Information System (INIS)

    Pagabeleguem, Soumaila; Seck, Momar Talla; Sall, Baba

    2015-01-01

    The application of the sterile insect technique (SIT) requires mass-production of sterile males of good biological quality. The size of the project area will in most cases determine whether it is more cost effective to produce the sterile flies locally (and invest in a mass-rearing facility) or import the sterile flies from a mass-rearing facility that is located in another country. This study aimed at assessing the effect of long distance transport of sterile male Glossina palpalis gambiensis pupae on adult male fly yield. The male pupae were produced at the Centre International de Recherche-Developpement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso, and shipped with a commercial courier service in insulated transport boxes at a temperature of ±10° to Senegal (36 h of transport). Upon arrival in the insectary in Dakar, the pupae were transferred to an emergence room and the flies monitored for 3-6 days. The results showed that the used system of isothermal boxes that contained phase change material packs (S8) managed to keep the temperature at around 10° which prevented male fly emergence during transport. The emergence rate was significantly higher for pupae from batch 2 (chilled at 4° for one day in the source insectary before transport) than those from batch 1 (chilled at 4° for two days in the source insectary before transport) i.e. an average (±sd) of 76.1 ± 13.2% and 72.2 ± 14.3%, respectively with a small proportion emerging during transport (0.7 ± 1.7% and 0.9 ± 2.9%, respectively). Among the emerged flies, the percentage with deformed (not fully expanded) wings was significantly higher for flies from batch 1 (12.0 ± 6.3%) than from batch 2 (10.7 ± 7.5%). The amount of sterile males available for release as a proportion of the total pupae shipped was 65.8 ± 13.3% and 61.7 ± 14.7% for batch 1 and 2 pupae, respectively. The results also showed that the temperature inside the parcel must be controlled around 10° with a

  1. Quality management systems for fruit fly (Diptera: Tephritidae) sterile insect technique

    International Nuclear Information System (INIS)

    Caceres, C.; Robinson, A.; McInnis, D.; Shelly, T.; Jang, E.; Hendrichs, J.

    2007-01-01

    The papers presented in this issue are focused on developing and validating procedures to improve the overall quality of sterile fruit flies for use in area-wide integrated pest management (AW-IPM) programs with a sterile insect technique (SIT) component. The group was coordinated and partially funded by the Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria, under a five-year Coordinated Research Project (CRP) on 'Quality Assurance in Mass-Reared and Released Fruit Flies for Use in SIT Programmes'. Participants in the CRP from 16 countries came from both basic and applied fields of expertise to ensure that appropriate and relevant procedures were developed. A variety of studies was undertaken to develop protocols to assess strain compatibility and to improve colonization procedures and strain management. Specific studies addressed issues related to insect nutrition, irradiation protocols, field dispersal and survival, field cage behavior assessments, and enhancement of mating competitiveness. The main objective was to increase the efficiency of operational fruit fly programs using sterile insects and to reduce their cost. Many of the protocols developed or improved during the CRP will be incorporated into the international quality control manual for sterile tephritid fruit flies, standardizing key components of the production, sterilization, shipment, handling, and release of sterile insects. (author) [es

  2. Diets based on soybean protein for Mediterranean fruit fly

    International Nuclear Information System (INIS)

    Sobrinho, Raimundo Braga; Caceres, Carlos; Islam, Amirul; Wornoayporn, Vivat; Enkerlin, Walter

    2006-01-01

    The objective of this work was to develop suitable and economic diets for mass rearing Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae). Diets containing sugar beet bagasse, wheat bran, brewer yeast, and others with wheat bran and palletized soybean protein from Brazil were tested. Diets based on soybean protein have shown promising results regarding pupal recovery, pupal weight and adult emergence. Soybean bagasse in the form of pellets with 60% of protein can be a very important substitute for other expensive sources of protein. (author)

  3. Diets based on soybean protein for Mediterranean fruit fly

    Energy Technology Data Exchange (ETDEWEB)

    Sobrinho, Raimundo Braga [Embrapa Agroindustria Tropical, Rua Dra. Sara Mesquita, 2270, CEP 60511-110 Fortaleza, CE (Brazil)]. E-mail: braga@cnpat.embrapa.br; Caceres, Carlos; Islam, Amirul; Wornoayporn, Vivat [Food and Agriculture Organization (FAO), International Atomic Energy Agency (IAEA), Agriculture and Biotechnology Laboratory, A-2444 Seibersdorf (Austria)]. E-mail: C.Caceres@iaea.org; Enkerlin, Walter [Insect Pest Control Section, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Vienna (Austria)]. E-mail: W.Enkerlin@iaea.org

    2006-04-15

    The objective of this work was to develop suitable and economic diets for mass rearing Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae). Diets containing sugar beet bagasse, wheat bran, brewer yeast, and others with wheat bran and palletized soybean protein from Brazil were tested. Diets based on soybean protein have shown promising results regarding pupal recovery, pupal weight and adult emergence. Soybean bagasse in the form of pellets with 60% of protein can be a very important substitute for other expensive sources of protein. (author)

  4. Status of the control of mediterranean fruit fly, ceratitis capitata (WIED.) using the sterile insect technique (SIT). Vol. 1

    Energy Technology Data Exchange (ETDEWEB)

    Wakid, A M [Biological Application Department, Nuclear Research Center, Atomic Energy Authority, Cairo (Egypt)

    1996-03-01

    This note presents the importance of the medfly, ceratitis capitata (Wied.) in the world especially in the med east region including egypt. Evaluation of the control methods used and the application of the sterile insect technique (SIT) as a successful and safe method for the fly eradication or control in many countries are considered. Moreover, the important requirements for a successful SIT programme and the trial for improvement of this technique are discussed including the improvement of the larval rearing media, male only release, trapping and attracting systems of the adult fly, and the current research on genetic sexing for elimination of females that cause great losses to after release.

  5. Status of the control of mediterranean fruit fly, ceratitis capitata (WIED.) using the sterile insect technique (SIT). Vol. 1

    International Nuclear Information System (INIS)

    Wakid, A.M.

    1996-01-01

    This note presents the importance of the medfly, ceratitis capitata (Wied.) in the world especially in the med east region including egypt. Evaluation of the control methods used and the application of the sterile insect technique (SIT) as a successful and safe method for the fly eradication or control in many countries are considered. Moreover, the important requirements for a successful SIT programme and the trial for improvement of this technique are discussed including the improvement of the larval rearing media, male only release, trapping and attracting systems of the adult fly, and the current research on genetic sexing for elimination of females that cause great losses to after release

  6. Practical application of insect-parasitic nematodes and sterile flies

    International Nuclear Information System (INIS)

    Galle, F.; Loosjes, M.

    1987-01-01

    The company 'de Groene Vlieg' started with commercial control of the onion fly by means of the sterile insect technique. At the moment 10 per cent of the Dutch spring sown onions are treated with this method. The mass-rearing, the estimations of populations and the repeated releases of sterilized flies make it a rather complicated method. It can be applied economically per field, but only in areas with a concentration of onion growing. For export we see no possibilities yet. In principle the sterile insect technique can be applied also to other flies (carrot rust fly, cabbage root fly), but a suitable artificial diet is still lacking. Since some years we also rear the insect parasitic nematodes Heterorhabditis sp. and Neoaplectana bibionis. The later is experimentally used with success against Agrotis segetum caterpillars in lettuce. Research will yield more applications of nematodes against different pests. We use Heterorhabditis sp. in practice against the black vine weevil (Otiorhynchus sulcatus), a serious pest in glass houses, tree nurseries and gardens. Good control is achieved with a dose of one half to one million nematodes per square meter in moist soil and with temperatures above 12 degrees C. The application is similar to that of a chemical insecticide. The pest is killed by symbiontic bacteria, released by the nematodes after penetrating into the body cavity of the larvae. The nematodes are delivered by mail. If cooled they can be kept alive for over four weeks in the package. We export already to Switzerland and plan to export also to Western Germany. At this moment a possible admittance is under investigation in the Netherlands for application of a nuclear polyhedrosis virus against Spodoptera exigua caterpillars

  7. Developing Quality Control Procedures to Sustain a Supply of High Quality Blood for Mass Rearing Tsetse Flies

    Energy Technology Data Exchange (ETDEWEB)

    De Beer, C J; Venter, G J; Potgieter, F T [ARC-Onderstepoort Veterinary Institute, Old Soutpans Road, Private Bag X05, 0110 Onderstepoort (South Africa)

    2012-07-15

    Mass rearing tsetse flies Glossina spp. is dependent on the sustained availability of a high quality blood diet. In any mass rearing facility, the logistics for obtaining sterile, high quality fresh blood is challenging. An added complication is the influence of potential chemical, physical and microbiological elements present in the blood of donors, as well as contamination during collection, handling and storage. Research at the Agricultural Research Council - Onderstepoort Veterinary institute (ARC-OVI) is directed towards the development of quality control procedures for the supply of the in vitro diet used to maintain productive colonies of Glossina brevipalpis Newstead and Glossina austeni Newstead. Factors that may influence the blood diet, e.g. defibrination, feeding times, collection of blood in anticoagulants, treatment of blood with taste stimuli, repeated freezing and thawing of blood, effect of bovine growth hormones, and also a preference for bovine or porcine blood were tested. A 25 day bioassay was used to determine the effects of these factors on tsetse survival and reproduction. Defibrination of the blood for 10 to 15 minutes gave the best results for both species. It was found that G. brevipalpis should be fed three times per week for 5 minutes each time, and G. austeni three times per week for 10 minutes. Heparin, acid citrate dextrose (ACD), citric acid, citrate phosphate dextrose adenine (CPDA) and a combination of sodium citrate and citric acid were effective anticoagulants in the blood diets of G. brevipalpis and G. austeni. Blood treated with inosine triphosphate (ITP) gave the highest quality factor (QFC) values for both G. austeni and G. brevipalpis. Repeated freezing and thawing of blood definitely affects pupal production negatively; G. brevipalpis especially produced significantly smaller pupae. A premixed diet of equal amounts of bovine and porcine blood was found to be best suited for G. brevipalpis, and for G. austeni a mixture of

  8. Studies on the Effect of E-Selen as Antioxidant in Ameliorating the Physiological Status of Gamma-Irradiated Mediterranean Fruit Fly,Ceratits capitata (Wied.)

    International Nuclear Information System (INIS)

    Zaghloul, Y.S.; Abbassy, S.A.; Elakhdar, E.A.H.

    2013-01-01

    Biologically based control methods, such as the Sterile Insect Technique (SIT), which relies on the sterilization by irradiation of large numbers of insects, is gaining an increasing role in the control of medfly in Mediterranean areas. However, the exposure of cells to ionizing radiation leads to the formation of reactive oxygen species (ROS) that are associated with radiation-induced cytotoxicity. Because of the serious damaging potential of ROS, cells depend on the elaboration of the antioxidant defense system (AODS), both enzymatic and non enzymatic oxidant defense mechanisms. Enzymes of antioxidative defense system – peroxidase, esterasase and alcohol dehydrogenase are known to play an important main role in endogenous cell protection from oxidative damage.The antioxidant Eselenis an exogenous antioxidant containing both selenium and vitamin E. It was added to the larval artificial diets of the Mediterranean fruit fly, C. capitata in various concentrations. The produced full grown pupae were exposed to gamma rays at dose rate of 90Gy (sterilizing dose) and are used during this experiment. The purpose of this study was to determine the effects of gamma-irradiation on C. capitata endogenous antioxidant activity (peroxidase, esterase and alcohol dehydrogenase and to examine whether the presence of eselen has the influence on activity of antioxidant and in reducing consequently the oxidative stress and tissue injury induced by gamma radiation in thefruit fly, C. capitata (Wied.). The results indicated that antioxidant pretreatments to the larval rearing dietand irradiation of the produced full grown pupae may have some beneficial effects against irradiation-induced injury to success the application of the sterile insect technique (SIT) for controlling the Med fly, C. capitata .

  9. Adding guarana powder to medfly diets: an alternative for improving the Sterile Insect Technique

    Directory of Open Access Journals (Sweden)

    Jamile Câmara de Aquino

    2016-06-01

    Full Text Available ABSTRACT Ceratitis capitata (medfly is a globally important horticultural pest that can be controlled using the sterile insect technique (SIT, but the success of SIT depends on the sexual performance of mass-reared males when released into the field. We added “guarana” (Paullinia cupana powder (derived from an Amazonian fruit that is considered to be a stimulant with aphrodisiac effects, capable of improving human physical stamina to the diets of adult male medflies to determine whether it increased their sexual performance. The basic diet of a protein extract + sucrose (1:3 was enriched with guarana powder (3 % on a volume basis. Experiments examining sexual competitiveness were performed using lab-reared males fed with the enriched diet vs. lab-reared males fed on the basic diet (and lab-reared females fed on the basic diet, as well as lab-reared males fed with the enriched diet vs. wild males fed on the basic diet (and wild females fed on the basic diet. The results of both experiments indicated that males maintained on diets enriched with guarana powder showed higher copulation successes than males fed only with the basic diet. Guarana powder therefore contributed to the greater mating success of lab-reared males (probably because of its stimulant properties, and may represent a new and viable option for increasing SIT effectiveness.

  10. Mediterranean fruit fly

    International Nuclear Information System (INIS)

    1982-01-01

    The Mediterranean Fruit Fly (Medfly, Ceratitis capitata), widespread in most tropical and subtropical area, lays eggs under the skin of fruit. Its larvae feed on the pulp, causing tremendous losses for agriculture. Insecticides, besides being hazardous for the environment, have proven too slow for effective pest control (eradication in 20 generations). This training film demonstrates in 7 detailed steps how the Sterile Insect Technique (SIT) can lead to elimination of the insect population within 6 generations. It shows different stages of breeding and describes the sterilization of pupae by exposure to gamma rays provided by a cobalt 60 source

  11. Mediterranean fruit fly

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1983-12-31

    The Mediterranean Fruit Fly (Medfly, Ceratitis capitata), widespread in most tropical and subtropical area, lays eggs under the skin of fruit. Its larvae feed on the pulp, causing tremendous losses for agriculture. Insecticides, besides being hazardous for the environment, have proven too slow for effective pest control (eradication in 20 generations). This training film demonstrates in 7 detailed steps how the Sterile Insect Technique (SIT) can lead to elimination of the insect population within 6 generations. It shows different stages of breeding and describes the sterilization of pupae by exposure to gamma rays provided by a cobalt 60 source

  12. INFLUENCE OF LARVAL REARING DIET ACIDITY ON THE QUANTITY AND QUALITY YIELD OF THE MEDITERRANEAN FRUIT FLY CERATITIS CAPITATA (Wied.) (DIPTERA: TEPHRITIDAE) FOR ITS CONTROL BY STERILE INSECT TECHNIQUE (SIT)

    International Nuclear Information System (INIS)

    SHOMAN, A.A.; EL-KHOLY, E.M.S.

    2008-01-01

    The biological effects of larval rearing diet acidity on the developmental stages of the medfly C. capitata (Wied.) were studied at the laboratory scale. Diets were formulated at five different initial pH ranging from 4.59 to 2.09 together with the control group currently used in our laboratory (5.26). These effects were evaluated on larval period, percent pupal recovery, pupal weight, percent adult emergence, percent male production and adult flight ability. The results showed that the shortest larval development occurred at pH 3.48 and 3.75, the highest pupal recovery at pH 3.75, the best pupal weight at pH 2.09, 3.48, 3.75 and 4.59, the highest percent adult emergence at pH 3.75, the highest percentage male production at pH 3.48, and the best percentage of fliers at pH 4.59. The obtained data referred to the optimizing physiochemical factors such as pH can improve the overall yield of mass reared medfly in the laboratory to be irradiated by gamma radiation and released in the field for controlling the insect

  13. Sterile neutrino

    International Nuclear Information System (INIS)

    Anon.

    2007-01-01

    Paper deals with the information on the occurrence of the fields of the sterile neutrinos (the righthanded ones) mixed with the normal neutrinos (the lefthanded ones). Both the Max Plank Radioastronomy Institute and the Los Angeles University assumes that the occurrence of the keV mass sterile neutrinos may explain the dark matter nature, the fast rotation of the observed pulsars and the reionization processes. The issues associated with the possibility to record the sterile neutrinos were analyzed in the course of the Sterile Neutrinos in Astrophysics and Cosmology Workshop (Crans Montana, March 2006 [ru

  14. Genetic or mechanical sexing system for the Mediterranean fruit fly, Ceratitis capitata (Wied.)

    International Nuclear Information System (INIS)

    Walder, J.M.M.

    1990-01-01

    A black puparium, monofactorial mutant was isolated in 1983 from a laboratory colony of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann). The mutant was used to construct a genetic sexing strain based on pupal sorting. Translocations were induced in wild male adults, 48 hours old, by gamma radiation (55 Gy; 60 Co). These males were crossed to black pupae females and produced two pupal sorting strains (T-44 and T-213) in 1987. These strains were lost after six generations. In another series of translocation inductions the strain T-87B was screened. Rearing the strain for eight generations in the laboratory provided no indication of instability in the strain. T-87B is now being mass reared. (author). 16 refs, 4 tabs

  15. Viruses in laboratory-reared cactus moth, Cactoblastis cactorum (Lepidoptera: Pyralidae)

    International Nuclear Information System (INIS)

    Marti, O.G.; Myers, R.E.; Carpenter, J.E.; Styer, E.L.

    2007-01-01

    The cactus moth, Cactoblastis cactorum (Lepidoptera: Pyralidae: Phycitinae), is a non-native species threatening a variety of native cacti, particularly endangered species of Opuntia (Zimmerman et al. 2001), on the coast of the Gulf of Mexico. Cactoblastis cactorum populations have expanded from Florida northward along the Atlantic coast as far as Charleston, SC, and westward along the Gulf of Mexico to Dauphin Island, south of Mobile, AL. It is feared that further movement to the west will allow C. cactorum to enter the US desert Southwest and Mexico, particularly the latter. Numerous cactus species, especially those of the genera Opuntia and Nopalea, are native to the U.S. and Mexico. Local economies based on agricultural and horticultural uses of cacti could be devastated by C. cactorum (Vigueras and Portillo 2001). A bi-national control program between the US and Mexico is being developed, utilizing the sterile insect technique (SIT). In the SIT program, newly emerged moths are irradiated with a 60 Co source and released to mate with wild individuals. The radiation dose completely sterilizes the females and partially sterilizes the males. When irradiated males mate with wild females, the F1 progeny of these matings are sterile. In order for the SIT program to succeed, large numbers of moths must be reared from egg to adult on artificial diet in a quarantined rearing facility (Carpenter et al. 2001). Irradiated insects must then be released in large numbers at the leading edge of the invasive population and at times which coincide with the presence of wild individuals available for mating. Mortality from disease in the rearing colony disrupts the SIT program by reducing the numbers of insects available for release

  16. Redfish Lake Sockeye Salmon Captive Broodstock Rearing and Research, 1993 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Flagg, Thomas A.

    1994-11-01

    The National Marine Fisheries Service (NMFS), in cooperation with Idaho and BPA, has established captive broodstocks to aid recovery of endangered Snake River sockeye salmon. NMFS is currently maintaining four separate Redfish Lake sockeye Salmon captive broodstocks; all these broodstocks are being reared full-term to maturity in fresh (well) water. Experiments are also being conducted on nonendangered 1990 and 1991-brood Lake Wenatchee (WA) sockeye salmon to compare effects on survival and reproduction to maturity in fresh water and seawater; for both brood-years, fish reared in fresh water were larger than those reared in seawater. Data from captive rearing experiments suggest a ranking priority of circular tanks supplied with pathogen-free fresh water, circular tanks supplied with pumped/filtered/uv-sterilized seawater, and seawater net-pens for rearing sockeye salmon to maturity.

  17. A see-saw mechanism with light sterile neutrinos

    International Nuclear Information System (INIS)

    McKellar, B.H.J.; Garbutt, M.; Stephenson, G.J.; Goldman, T.

    2001-01-01

    The usual see-saw mechanism for the generation of light neutrino masses is based on the assumption that all of the flavours of right-handed (more properly, sterile) neutrinos are heavy. If the sterile Majorana mass matrix is singular, one or more of the sterile neutrinos will have zero mass before mixing with the active (left-handed) neutrinos and be light after that mixing is introduced In particular, a rank 1 sterile mass matrix leads naturally to two pseudo-Dirac pairs, one very light active Majorana neutrino and one heavy sterile Majorana neutrino. For any pattern of Dirac masses, there exists a region of parameter space in which the two pseudo-Dirac pairs are nearly degenerate in mass. This, in turn, leads to large amplitude mixing of active states as well as mixing into sterile states

  18. Genetic technologies to enhance the Sterile Insect Technique (SIT)

    International Nuclear Information System (INIS)

    Alphey, Luke; Baker, Pam; Condon, George C.; Condon, Kirsty C.; Dafa'alla, Tarig H.; Fu, Guoliang; Jin, Li; Labbe, Genevieve; Morrison, Neil M.; Nimmo, Derric D.; O'Connell, Sinead; Phillips, Caroline E.; Plackett, Andrew; Scaife, Sarah; Woods, Alexander; Burton, Rosemary S.; Epton, Matthew J.; Gong, Peng

    2006-01-01

    The Sterile Insect Technique (SIT) has been used very successfully against range of pest insects, including various tephritid fruit flies, several moths and a small number of livestock pests. However, modern genetics could potentially provide several improvements that would increase the cost-effectiveness of SIT, and extend the range of suitable species. These include improved identification of released individuals by incorporation of a stable, heritable, genetic marker; built-in sex separation (genetic sexing); reduction of the hazard posed by non-irradiated accidental releases from mass-rearing facility (fail-safe); elimination of the need for sterilization by irradiation (genetic sterilization). We discuss applications of these methods and the state of the art, at the time of this meeting, in developing suitable strains. We have demonstrated, in several key pest species, that the required strains can be constructed by introducing a repressible dominant lethal genetic system, a method known as RIDL(trade mark). Based on field experience with Medfly, incorporation of a genetic sexing system into SIT programs for other tephritids could potentially provide a very significant improvement in cost-effectiveness. We have now been able to make efficient female-lethal strains for Medfly. One advantage of our approach is that it should be possible rapidly to extend this technology to other fruit fly species; indeed we have recently been able also to make genetic sexing strains of Medfly (Anastrepha ludens). (author)

  19. Genetic technologies to enhance the Sterile Insect Technique (SIT)

    Energy Technology Data Exchange (ETDEWEB)

    Alphey, Luke; Baker, Pam; Condon, George C; Condon, Kirsty C; Dafa' alla, Tarig H; Fu, Guoliang; Jin, Li; Labbe, Genevieve; Morrison, Neil M; Nimmo, Derric D; O' Connell, Sinead; Phillips, Caroline E; Plackett, Andrew; Scaife, Sarah; Woods, Alexander [Oxitec Ltd., Oxford (United Kingdom); Burton, Rosemary S; Epton, Matthew J; Gong, Peng [University of Oxford (United Kingdom). Dept. of Zoology

    2006-07-01

    The Sterile Insect Technique (SIT) has been used very successfully against range of pest insects, including various tephritid fruit flies, several moths and a small number of livestock pests. However, modern genetics could potentially provide several improvements that would increase the cost-effectiveness of SIT, and extend the range of suitable species. These include improved identification of released individuals by incorporation of a stable, heritable, genetic marker; built-in sex separation (genetic sexing); reduction of the hazard posed by non-irradiated accidental releases from mass-rearing facility (fail-safe); elimination of the need for sterilization by irradiation (genetic sterilization). We discuss applications of these methods and the state of the art, at the time of this meeting, in developing suitable strains. We have demonstrated, in several key pest species, that the required strains can be constructed by introducing a repressible dominant lethal genetic system, a method known as RIDL(trade mark). Based on field experience with Medfly, incorporation of a genetic sexing system into SIT programs for other tephritids could potentially provide a very significant improvement in cost-effectiveness. We have now been able to make efficient female-lethal strains for Medfly. One advantage of our approach is that it should be possible rapidly to extend this technology to other fruit fly species; indeed we have recently been able also to make genetic sexing strains of Medfly (Anastrepha ludens). (author)

  20. Viruses of insects reared for food and feed

    DEFF Research Database (Denmark)

    Maciel Vergara, Gabriela; Ros, Vera I.D.

    2017-01-01

    The use of insects as food for humans or as feed for animals is an alternative for the increasing high demand for meat and has various environmental and social advantages over the traditional intensive production of livestock. Mass rearing of insects, under insect farming conditions or even...... with large-scale sequencing techniques, new viruses are rapidly being discovered. We discuss factors affecting the emergence of viruses in mass rearing systems, along with virus transmission routes. Finally we provide an overview of the wide range of measures available to prevent and manage virus outbreaks...... for the productivity and the quality of mass rearing systems. Prevention and management of viral diseases imply the understanding of the different factors that interact in insect mass rearing. This publication provides an overview of the known viruses in insects most commonly reared for food and feed. Nowadays...

  1. Standard Operating Procedures for Preparing and Handling Sterile Male Tsetse flies for Release

    International Nuclear Information System (INIS)

    Argiles-Herrero, Rafa; Leak, Stephen G.A.

    2016-01-01

    The purpose of this SOP is to describe the procedures involved in preparing tsetse flies reared in a breeding facility for release in the field for the sterile insect technique (SIT) as a component of Area-Wide Insect pest Management (AW-IPM). Following the procedures which are outlined will help to ensure that the released sterile male tsetse flies are of optimal quality.

  2. The sterile-insect technique for the control of fruit flies: a survey

    International Nuclear Information System (INIS)

    Harris, E.J.

    1975-01-01

    Some advantages of the sterile-insect technique (SIT) are its minimum contribution to environmental pollution and its minimum adverse effect on non-target organisms. A review is made of the melon fly and sterile Mediterranean fruit fly release programmes, the accomplishments, and the implications. Recommendations are made for research leading to development of methods for practical use of the SIT. (author)

  3. Advances and perspectives in the mass rearing of fruit fly parasitoids in Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Cancino, Jorge; Montoya, Pablo [Secretaria de Agricultura, Ganaderia, Desarrollo Rural, Pesca y Alimentacion (DGSV/SENASICA/SAGARPA), Chiapas (Mexico). Servicio Nacional de Sanidad, Inocuidad y Calidad Agroalimentaria. Programa Moscamed-Moscafrut

    2006-07-01

    Biological control by augmentation is applied in Mexico as part of an integrated pest management program against native fruit flies of the genus Anastrepha Schiner. The exotic parasitoid Diachasmimorpha longicaudata has been the most important species used within this context. A program for the mass rearing of 50 million parasitized pupa per week has been established in southeast Mexico, and these are released into the field according to a yearly national plan based on industry requirements. In order to reduce costs and optimize procedures, important advances have been made in the technology for mass production, including an increase in the weight of host larvae (24 mg), changes in the management of host exposition, improvements in the management of environmental conditions, suitability in time and motions are the main areas addressed. Furthermore, a quality control program is routinely applied, and the key parameters under constant evaluation are: 1) weight and volume of host larvae, 2) host mortality after exposure, 3) weight and volume of pupae, and 4) percent parasitoid viability and percent emergence. Good performance in these parameters produces adults with adequate longevity and fecundity, high flight ability and good searching behavior. The introduced egg parasitoid Fopius arisanus and the native pupal parasitoid Coptera hawardi are being evaluated for use in the future as a complement to releases into the field of D. longicaudata. Manipulating host size and exposition time, the use of starting diet and suppressing host development by irradiation, have permitted the effective use of Anastrepha eggs as hosts for the rearing of F. arisanus. Further achievements in the mass rearing of C. haywardi (e.g., the suppression of unparasitized hosts after irradiation), could give us the opportunity to employ new options to reinforce the augmentative biological control of Anastrepha fruit flies in Mexico. (author)

  4. Advances and perspectives in the mass rearing of fruit fly parasitoids in Mexico

    International Nuclear Information System (INIS)

    Cancino, Jorge; Montoya, Pablo

    2006-01-01

    Biological control by augmentation is applied in Mexico as part of an integrated pest management program against native fruit flies of the genus Anastrepha Schiner. The exotic parasitoid Diachasmimorpha longicaudata has been the most important species used within this context. A program for the mass rearing of 50 million parasitized pupa per week has been established in southeast Mexico, and these are released into the field according to a yearly national plan based on industry requirements. In order to reduce costs and optimize procedures, important advances have been made in the technology for mass production, including an increase in the weight of host larvae (24 mg), changes in the management of host exposition, improvements in the management of environmental conditions, suitability in time and motions are the main areas addressed. Furthermore, a quality control program is routinely applied, and the key parameters under constant evaluation are: 1) weight and volume of host larvae, 2) host mortality after exposure, 3) weight and volume of pupae, and 4) percent parasitoid viability and percent emergence. Good performance in these parameters produces adults with adequate longevity and fecundity, high flight ability and good searching behavior. The introduced egg parasitoid Fopius arisanus and the native pupal parasitoid Coptera hawardi are being evaluated for use in the future as a complement to releases into the field of D. longicaudata. Manipulating host size and exposition time, the use of starting diet and suppressing host development by irradiation, have permitted the effective use of Anastrepha eggs as hosts for the rearing of F. arisanus. Further achievements in the mass rearing of C. haywardi (e.g., the suppression of unparasitized hosts after irradiation), could give us the opportunity to employ new options to reinforce the augmentative biological control of Anastrepha fruit flies in Mexico. (author)

  5. Some Chemical Elements in Gamma Irradiated Adults of the Mediterranean Fruit Fly, Ceratitis capitata (Wied.) Fed on Different Diets

    International Nuclear Information System (INIS)

    Elakhdar, E.A.H.

    2013-01-01

    The elemental composition of four yeast diets differ in protein composition and mixed with sugar as a carbohydrate source were compared with a standard yeast diet used for the mass rearing of med fly C. capitata. The cost availability and the effects on the quality of reared flies were the main measures for these comparisons. Moreover, the elemental composition of reared flies on the tested diets either irradiated to gamma radiation or normal beside full grown pupae (F1) were detected and compared with those reared on standard diet . Data obtained revealed that ten elements (K, N, Na, P, Ca, Fe, Mg, Zn, Mn and Cu) were detected and classified according to their quantities .However those quantities varied according to the type of used yeast ,insect stage , insect sex and irradiated dose. The major group (K, N, Na and P), moderate group (Ca, Fe and Mg) and minor group (Zn, Mn and Cu) remained unchanged although their quantities were changed inside each group. In addition, a significant increase in K, N, Na, P and Ca when diet No.4 (D4) was used to feed flies. These findings may enhance the opportunity of sterile insect technique (SIT). However Fe and Zn ions were decreased with changing the standard yeast and this is may contradict SIT. Also when normal females fed on all tested yeasts, the concentrations of the ten elements increased as compared to those fed on standard diet. These results may increase the efficiency of sterilized reared insects to compete with the native insects in the field

  6. Radiation induced F1 sterility in Helicoverpa zea (Boddie): Potential for area-wide control

    International Nuclear Information System (INIS)

    Carpenter, J.E.

    1993-01-01

    The potential of using F 1 sterility as a management strategy for the corn earworm (CEW), Helicoverpa zea (Boddie), has been revealed through laboratory and field investigations. A 100 Gy dose of radiation induced deleterious effects in CEWs' which were inherited through several generations. Irradiated, laboratory reared CEWs were competitive with non-irradiated, laboratory reared CEWs in attracting and securing mates under field conditions. Females that mated to non-irradiated males and males irradiated with 100 Gy had the same mating propensity and the same intermating interval. Although there was a difference in mortality between larvae from irradiated and non-irradiated parents when reared in the laboratory, this mortality differential was reduced when larvae were reared under natural conditions in the field. Other studies revealed that there was no interaction between inherited sterility and diapause in CEWs when depth of pupation, initiation and termination of diapause, egg hatch, fecundity or survival were investigated. A pilot test that investigated the efficacy of using inherited sterility for suppressing seasonal population increases of CEWs was conducted from 1988 to 1990. Results of the pilot test revealed that irradiated (100 Gy) males released in mountain valleys were competitive with wild males in infusing their genes into the wild population. Analysis of seasonal population curves of wild CEW males calculated from mark-recapture data suggested that seasonal increases in wild CEW males were delayed or reduced in valleys where irradiated males were released. (author). 19 refs, 3 figs

  7. Efficacy of Blood Sources and Artificial Blood Feeding Methods in Rearing of Aedes aegypti (Diptera: Culicidae for Sterile Insect Technique and Incompatible Insect Technique Approaches in Sri Lanka

    Directory of Open Access Journals (Sweden)

    Nayana Gunathilaka

    2017-01-01

    Full Text Available Introduction. Selection of the artificial membrane feeding technique and blood meal source has been recognized as key considerations in mass rearing of vectors. Methodology. Artificial membrane feeding techniques, namely, glass plate, metal plate, and Hemotek membrane feeding method, and three blood sources (human, cattle, and chicken were evaluated based on feeding rates, fecundity, and hatching rates of Aedes aegypti. Significance in the variations among blood feeding was investigated by one-way ANOVA, cluster analysis of variance (ANOSIM, and principal coordinates (PCO analysis. Results. Feeding rates of Ae. aegypti significantly differed among the membrane feeding techniques as suggested by one-way ANOVA (p0.05. Conclusions. Metal plate method could be recommended as the most effective membrane feeding technique for mass rearing of Ae. aegypti, due to its high feeding rate and cost effectiveness. Cattle blood could be recommended for mass rearing Ae. aegypti.

  8. Influence of Pupation Substrate on Mass Production and Fitness of Adult Anastrepha obliqua Macquart (Diptera: Tephritidae) for Sterile Insect Technique Application.

    Science.gov (United States)

    Aceituno-Medina, Marysol; Rivera-Ciprian, José Pedro; Hernández, Emilio

    2017-12-05

    Tephritid mass-rearing systems require an artificial substrate for pupation. Pupation substrate characteristics influence the quality of insects produced. Coconut fiber, as an alternative to the conventional pupation substrate vermiculite, was evaluated for Anastrepha obliqua Macquart (Diptera: Tephritidae) pupation behavior (pupation patterns, distribution, respiration rate, and pupal weight) and adult fitness (adult eclosion time, flight ability, and male mating competitiveness). Pupation percentage at 24 h, pupal weight, and flight ability were not significantly affected by substrate type. Adult eclosion levels of 50% were reached at 29.7 and 41.6 h for coconut fiber and vermiculite, respectively. Pupae distribution patterns differed between substrates because the larval aggregation level was reduced during the pupation process in coconut fiber. The pupae aggregation was three times greater in vermiculite than in coconut fiber. A higher respiratory rate in the last days of pupation and adult eclosion were recorded in the insects maintained in coconut fiber. Coconut fiber suitability as a pupation substrate for quality mass production of pupae and its implications for sterile insect technique are discussed. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Viruses of insects reared for food and feed.

    Science.gov (United States)

    Maciel-Vergara, Gabriela; Ros, Vera I D

    2017-07-01

    The use of insects as food for humans or as feed for animals is an alternative for the increasing high demand for meat and has various environmental and social advantages over the traditional intensive production of livestock. Mass rearing of insects, under insect farming conditions or even in industrial settings, can be the key for a change in the way natural resources are utilized in order to produce meat, animal protein and a list of other valuable animal products. However, because insect mass rearing technology is relatively new, little is known about the different factors that determine the quality and yield of the production process. Obtaining such knowledge is crucial for the success of insect-based product development. One of the issues that is likely to compromise the success of insect rearing is the outbreak of insect diseases. In particular, viral diseases can be devastating for the productivity and the quality of mass rearing systems. Prevention and management of viral diseases imply the understanding of the different factors that interact in insect mass rearing. This publication provides an overview of the known viruses in insects most commonly reared for food and feed. Nowadays with large-scale sequencing techniques, new viruses are rapidly being discovered. We discuss factors affecting the emergence of viruses in mass rearing systems, along with virus transmission routes. Finally we provide an overview of the wide range of measures available to prevent and manage virus outbreaks in mass rearing systems, ranging from simple sanitation methods to highly sophisticated methods including RNAi and transgenics. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Development of mass production, gamma sterilization and release of the codling moth, Laspeyresia pomonella L. Part of a coordinated programme on the use of the sterile male technique for control of lepidopterous insects attacking fruit and forest trees

    International Nuclear Information System (INIS)

    Suski, Z.W.

    1979-03-01

    Research on codling moths was conducted from Spring 1973 to Autumn 1978 and included rearing of larvae on thinning apples and artificial diet ecology, radiation sterilization and the effect of field releases of sterile moths in suppressing the wild population. Field releases of irradiated with 30 Krad unsexed insects were conducted in two consecutive seasons, namely in 1977 and 1978 and aimed at a sterile to wild ratio of 97:1 and 233:1 respectively. The experimentally obtained ratio, however, based on catches in traps baited with sex attractant was 24:1 and 79:1 respectively. Examination of fruit infestation at harvest revealed an increase in infestation by 9% in the 1977 sterile release programme and by 56% in the 1978 programme. Likely causes of the failure of the SIT programme were the immigration of fertile females from the surrounding area and inadequate mating competitiveness of the released moths due to somatic damage caused by the irradiation and laboratory adaptation. The sharp increase of fruit infestation in 1978 was very likely the result of a six fold increase in yield which provided a better chance of survival for hatching larvae

  11. Security in the Mediterranean basin: terrorism and weapons of mass destruction

    International Nuclear Information System (INIS)

    Benoit, L.

    2006-01-01

    The european union has appreciated the gravity of the threat from terrorism and weapons of mass destruction, and has adopted a strategy for keeping up its guard, particularly in the Mediterranean basin. The author reviews what is being done to meet these scourges. (author)

  12. Programme for the control of Glossina palpalis gambiensis Vanderplanck by the sterile-male technique in Upper Volta. A study of operational parameters

    International Nuclear Information System (INIS)

    Cuisance, D.; Politzar, H.; Clair, M.; Sellin, E.; Taze, Y.; Bourdoiseau, G.; Fevrier, J.

    1980-01-01

    The Institute for Stock-Breeding and Veterinary Medicine in Tropical Countries (Institut d'elevage et de medecine veterinaire des pays tropicaux - IEMVT, France), in association with the German Society for Technical Co-operation (Deutsche Gesellschaft fuer technische Zusammenarbeit - GTZ, Federal Republic of Germany), has been experimenting for four years in Upper Volta on genetic control of G.p. gambiensis, a vector of trypanosomiases in both man and animals, by the release of sterile males. A mass rearing facility has been set up for this glossina, with 45,000 females which produce 250,000 males for irradiation (11,000 rad) annually. This required a parallel facility for rearing 1000 host animals (400 rabbits and 600 guinea pigs). The releases are made twice a week on five experimental sectors isolated by barriers, which represent 32 km of forest galleries inhabited by G.p. gambiensis and G. tachinoides populations of medium density. The whole of this study zone is compared with a control covert 5.5 km in length. In each covert the influence of different parameters was examined: sterile-to-wild male ratio, spacing of release points, combination with insecticide treatment or not, and variation over time of the numbers of males released. First observations indicate that the sterile-male technique is efficient, and analysis of different parameters should make it possible to choose the optimum conditions for applying it. However, if the method is to be used on a larger scale, industrial-type rearing facilities will be required; yet the possibilities are limited by the difficulty of maintaining large numbers of host animals in tropical regions. Artificial feeding on membranes might offer one solution to the problem

  13. Consultants Group Meeting on Rational Supply of Sterile Flies for Medfly SIT in the Mediterranean Basin. Working Material

    International Nuclear Information System (INIS)

    2000-01-01

    The medfly, Ceratitis capitata, is a very damaging insect pest of citrus, stone fruit, pome fruit, figs, etc. in the Mediterranean Basin (MB) - The current insecticide based method for medfly control is causing serious environmental and insecticide residue problems throughout the MB - Producers, exporters, plant protection officials and environmentalists all are seeking ways to reduce insecticide usage against the medfly. - The sterile insect technique (SIT) is a proven method of managing the medfly on an area wide basis. It is the only alternative to repeated insecticide treatments for medfly control. The SIT is environmentally friendly and little or no insecticide is involved in SIT based insect control systems. - The SIT is routinely used against the medfly in Argentina, Chile, Guatemala, Mexico and the USA. - The SIT is not used against the medfly in the MB. There is a medfly control programme being developed in Madeira, Portugal. A demonstration is currently underway in Israel. Valencia, Spain and Algarve, Portugal are planning SIT demonstrations or programmes. Morocco and Corsica (France) are considering SIT efforts. Other MB countries are known to be considering the SIT for use against the medfly. - The major deterrent to using the SIT is lack of confidence that it really is effective and the perceived high cost of the technology. Efficacy has been repeatedly proven in the new world. Cost studies have clearly shown the SIT is not more expensive than insecticide based medfly control systems. Regardless demonstrations projects are required in the MB. - The limiting factor to one or more SIT based medfly control demonstrations in the MB is lack of a source of sufficient numbers of sterile male medflies. The only medfly factory in the MB is in Madeira and is too small to provide sufficient sterile flies. Thus it is imperative that for rapid development of the SIT for medfly control in the MB, a large medfly factory is essential. - The planned (IAEA supported

  14. Biological and Cultural Control of Olive Fruit Fly in California---Utilization of Parasitoids from USDA-APHIS-PPQ, Guatemala and Cultural Control Methods

    Science.gov (United States)

    The parasitoid Psytallia humilis = P. cf. concolor (Szépligeti) was reared on sterile Mediterranean fruit fly, Ceratitis capitata (Wiedemann), larvae at the USDA, APHIS, PPQ, Moscamed biological control laboratory in San Miguel Petapa, Guatemala and shipped to the USDA, ARS, Parlier, for biological ...

  15. Rice hulls a new bulking component for larval rearing of the mediterranean fruit fly, ceratitis capitata wied

    International Nuclear Information System (INIS)

    Wakid, A.M.; El-Kholy, E.M.S.; Shoman, A.A.; El-Akhdar, E.A.H.; Abdel Rahman, H.A.

    1998-01-01

    Rice hulls as a new bulking component for the larval rearing of the mediterranean fruit fly, ceratitis capitata wied. Was tested in the laboratory; and 4 formulas of rice hulls and wheat bran were evaluated biologically and financially. When rice hulls and wheat bran were mixed in the ratio of 3:1, all biological aspects and response to gamma radiation (90 Gy) of the produced adults were normal except for male fertility that decreased by about 13% of that of the bran medium (control); while male mating competitiveness was increased. When rice hulls were used without bran, only adult emergece and female fecundity were decreased by about 2% and 20%, respectively as compared to control medium (totally wheat bran); while larval duration increased by one day. The fourth formula consisting of wheat bran and rice hulls in the ratio of 1:1 showed the least favourite bulking component. Calculations showed that one million pupal production costed $26.6,22.2, 20.2 and 21.4 for the bulking ratios (hulls : bran) 0.1, 1:1, 3:1 and 1:0,respectively

  16. Effect of symbiotic bacteria added to the middle of the Mediterranean fruit fly larvae on the performance of sterile males

    International Nuclear Information System (INIS)

    Toukebri, Achraf; Kefi, Amal

    2009-01-01

    The program of the fight against the Mediterranean fly of fruits ''SIT'' becomes increasingly efficient when one control his various factors well mainly the performances of the sterile males within the unit. In this present work, we adopted a method of breeding which could improve quality of the sterile males intended for releasing. This method consists in introducing certain beneficial bacteria (Pseudomonas, Citrobacter and Klebsiella) into the milieu of breeding according to different combinations. The effect of these bacteria was analyzed by carrying out various tests of quality control to determin the parameters of quality (Productivity, weight, Emergence, flying aptitude) and the parameters of reproduction (latency time, Duration of coupling and competitiveness). According to the results obtained, we could observe changes on the level of the parameters of quality. The addition of Pseudomonas alone in the milieu of breeding significantly decreased the quality of the produced flies while the addition of this same bacteria in partnership with Citrobacter and Klebsiella showed a beneficial effect on their host. This is observed through the remarkable improvement of the competitiveness of the fly. Thus we can conclude that the presence of the bacteria alone or in synergy enormously affects the fitness flies and consequently their sexual competitiveness. (Author)

  17. World-wide sexual compatibility in Medfly, Ceratitis capitata (Wied.), and its implications for SIT

    International Nuclear Information System (INIS)

    Cayol, J.P.

    2000-01-01

    The concept of the sterile insect technique, described by Knipling (1953), to control and/or eradicate insect pest populations has been applied to many Lepidoptera and Diptera species. Among Diptera species, the Mediterranean fruit fly, Ceratitis capitata (Wied.) (Diptera: Tephritidae), is often referred to as the most important agricultural pest in the world (Liquido et al. 1990) and it is also a major target of SIT action programmes world-wide. The use of SIT requires that mass rearing facilities be developed to produce sterile insects for use in national programmes, with mass reared strains being established by colonising wild insects collected from the SIT target area. More recently, with the increasing demand for sterile Medflies and the limited number of production facilities, some rearing facilities began to export Medflies to other national/regional programmes. Eight facilities have now reached production levels which allow them to export sterile insects (Fisher and Caceres 199) on a regional or inter-regional basis. When this procedure is used, the flies released have to compete with wild flies of a different geographic origin. The increasing use of Medfly genetic sexing strains (GSS) has also resulted in the same strain being used in different countries. To date, five rearing facilities in the world produce GSS (Fisher and Caceres 1999). Since GSS are assembled from specific components, it is impossible to 'colonise' them from each country where sterile GSS flies are needed. The GSS are often backcrossed with insects from the target population to increase the genetic variability (Franz et al. 1996), although in some cases this presents problems (Franz, personal communication). In practice, a single wild population is used as a basis for the synthesis of the GSS. Consequently, the same GSS based on the same wild genetic material may be used in various countries/continents and the question was raised concerning the sexual compatibility of these strains with

  18. Mating competitiveness of sterile genetic sexing strain males (GAMA) under laboratory and semi-field conditions: Steps towards the use of the Sterile Insect Technique to control the major malaria vector Anopheles arabiensis in South Africa.

    Science.gov (United States)

    Munhenga, Givemore; Brooke, Basil D; Gilles, Jeremie R L; Slabbert, Kobus; Kemp, Alan; Dandalo, Leonard C; Wood, Oliver R; Lobb, Leanne N; Govender, Danny; Renke, Marius; Koekemoer, Lizette L

    2016-03-02

    Anopheles arabiensis Patton is primarily responsible for malaria transmission in South Africa after successful suppression of other major vector species using indoor spraying of residual insecticides. Control of An. arabiensis using current insecticide based approaches is proving difficult owing to the development of insecticide resistance, and variable feeding and resting behaviours. The use of the sterile insect technique as an area-wide integrated pest management system to supplement the control of An. arabiensis was proposed for South Africa and is currently under investigation. The success of this technique is dependent on the ability of laboratory-reared sterile males to compete with wild males for mates. As part of the research and development of the SIT technique for use against An. arabiensis in South Africa, radio-sensitivity and mating competitiveness of a local An. arabiensis sexing strain were assessed. The optimal irradiation dose inducing male sterility without compromising mating vigour was tested using Cobalt 60 irradiation doses ranging from 70-100 Gy. Relative mating competitiveness of sterile laboratory-reared males (GAMA strain) compared to fertile wild-type males (AMAL strain) for virgin wild-type females (AMAL) was investigated under laboratory and semi-field conditions using large outdoor cages. Three different sterile male to fertile male to wild-type female ratios were evaluated [1:1:1, 5:1:1 and 10:1:1 (sterile males: fertile, wild-type males: fertile, wild-type females)]. Irradiation at the doses tested did not affect adult emergence but had a moderate effect on adult survivorship and mating vigour. A dose of 75 Gy was selected for the competitiveness assays. Mating competitiveness experiments showed that irradiated GAMA male mosquitoes are a third as competitive as their fertile AMAL counterparts under semi-field conditions. However, they were not as competitive under laboratory conditions. An inundative ratio of 10:1 induced the

  19. Cosmology seeking friendship with sterile neutrinos

    DEFF Research Database (Denmark)

    Hamann, Jan; Hannestad, Steen; Raffelt, G.G.

    2011-01-01

    Precision cosmology and big-bang nucleosynthesis mildly favour extra radiation in the universe beyond photons and ordinary neutrinos, lending support to the existence of low-mass sterile neutrinos. We present bounds on the common mass scale ms and effective number Ns of thermally excited sterile ...

  20. Sterile Males of Ceratitis Capitata (Diptera: Tephritidae) as Disseminators of Beauveria Bassiana Conidia for IPM Strategies

    Energy Technology Data Exchange (ETDEWEB)

    Flores, Salvador; Campos, Sergio; Montoya, Pablo [Programa Moscafrut SAGARPA-IICA, Camino a los Cacahotales S/N, Metapa de Dominguez, Chiapas 30860 (Mexico); Villasenor, Antonio; Valle, Alvaro; Enkerlin, Walther [Codireccion Mexico, Programa Regional Moscamed Mexico- Guatemala-Estados Unidos (Guatemala); Toledo, Jorge; Liedo, Pablo [Departamento Agricultura Sociedad y Ambiente, El Colegio de la Frontera Sur. Carretera Antiguo Aeropuerto, Tapachula, Chiapas 30700 (Mexico)

    2014-01-15

    Full text: Sterile Mediterranean fruit fly, Ceratitis capitata (Wied.), males were evaluated as vectors to spread Beauveria bassiana (Bals) conidia to wild C. capitata populations under field conditions. The inoculated sterile males were released by air, using the chilled adult technique over 7000 ha of coffee growing in Chimaltenango, Guatemala, Central America. The impact of releases was determined using dry traps baited with a food attractant. The effects of these releases on Apis mellifera, Linnaeus (honey bee), Hypothenemus hampei, Ferrari (coffee berry borer) and the parasitic mite Varroa destructor (Oudeman) were also evaluated. Inoculated sterile males were able to transmit fungal spores to 44% of the wild C. capitata flies captured in traps, which likely were infected through intra- and intersexual interactions during leks, mating or mating attempts. There was no transmission of the fungal spores to non- target insect species such as coffee berry borer, honey bees or varroa. We conclude that sterile males of Mediterranean fruit fly inoculated with B. bassiana can act as effective vectors of conidia to wild populations, constituting a safe, environmentally friendly and selective alternative for suppressing the medfly under a Sterile Insect Technique-based IPM approach. (author)

  1. Impediment to symbiosis establishment between giant clams and Symbiodinium algae due to sterilization of seawater.

    Science.gov (United States)

    Kurihara, Takeo; Yamada, Hideaki; Inoue, Ken; Iwai, Kenji; Hatta, Masayuki

    2013-01-01

    To survive the juvenile stage, giant clam juveniles need to establish a symbiotic relationship with the microalgae Symbiodinium occurring in the environment. The percentage of giant clam juveniles succeeding in symbiosis establishment ("symbiosis rate") is often low, which is problematic for seed producers. We investigated how and why symbiosis rates vary, depending on whether giant clam seeds are continuously reared in UV treated or non treated seawater. Results repeatedly demonstrated that symbiosis rates were lower for UV treated seawater than for non treated seawater. Symbiosis rates were also lower for autoclaved seawater and 0.2-µm filtered seawater than for non treated seawater. The decreased symbiosis rates in various sterilized seawater suggest the possibility that some factors helping symbiosis establishment in natural seawater are weakened owing to sterilization. The possible factors include vitality of giant clam seeds, since additional experiments revealed that survival rates of seeds reared alone without Symbiodinium were lower in sterilized seawater than in non treated seawater. In conclusion, UV treatment of seawater was found to lead to decreased symbiosis rates, which is due possibly to some adverse effects common to the various sterilization techniques and relates to the vitality of the giant clam seeds.

  2. Aroma therapy and medfly SIT

    Energy Technology Data Exchange (ETDEWEB)

    Shelly, Todd E., E-mail: todd.e.shelly@aphis.usda.go [U.S. Department of Agriculture (USDA-APHIS), HI (United States). Animal and Plant Health Inspection

    2006-07-01

    A summary of the main findings of the research program on the biological competence of mass-reared, sterile males of the Mediterranean fruit fly (med fly), Ceratitis capitata (Wied.) and the development and implementation of the sterile insect technique (SIT) against this pest is presented. The potential application of aroma therapy to improve the mating success of sterile med fly males is studied. The report assumes a loosely chronological framework as it documents progression along two experimental scales: the number of males simultaneously exposed to ginger root oil, starting with small groups of 25 males and ending with rooms with nearly 200 million males; the experimental arena used to test the effects of aroma therapy, progressing from standard field-cages to large field enclosures to the open field. In addition, brief comments are offered regarding the potential negative effects of GRO exposure, the mechanisms underlying GRO-mediated improvement in male mating success, and the financial costs of GRO aroma therapy. (MAC)

  3. Aroma therapy and medfly SIT

    International Nuclear Information System (INIS)

    Shelly, Todd E.

    2006-01-01

    A summary of the main findings of the research program on the biological competence of mass-reared, sterile males of the Mediterranean fruit fly (med fly), Ceratitis capitata (Wied.) and the development and implementation of the sterile insect technique (SIT) against this pest is presented. The potential application of aroma therapy to improve the mating success of sterile med fly males is studied. The report assumes a loosely chronological framework as it documents progression along two experimental scales: the number of males simultaneously exposed to ginger root oil, starting with small groups of 25 males and ending with rooms with nearly 200 million males; the experimental arena used to test the effects of aroma therapy, progressing from standard field-cages to large field enclosures to the open field. In addition, brief comments are offered regarding the potential negative effects of GRO exposure, the mechanisms underlying GRO-mediated improvement in male mating success, and the financial costs of GRO aroma therapy. (MAC)

  4. RAF-5074: Enhancing Capacity for Detection, Surveillance and Suppression of Exotic and Established Fruit Fly Species through Integration of Sterile Insect Technique with Other Suppression Methods

    International Nuclear Information System (INIS)

    Musyoki, M.; Kasina, M.

    2017-01-01

    Fruit flies (Family Tephritidae) is one of the most destructive and economically challenging pest insect of fruits and vegetables. It is responsible for loss of export markets and poor farm gate prices of fruits and vegetables. Fruit flies are insects (Diptera) and undergoes complete metamorphosis: eggs- larva- pupa- adult. Only larva (maggots) are extremely damaging and the Adults in addition cause economic injury through stippling. The purpose of this project is to build capacity of African countries in the management of fruit flies using area wide approach and incorporating sterile insect technique (SIT ). sterile insect technique is a method that uses sterile insects (males) to flood them in the wild, and by so doing they mate with wild fertile individuals, resulting to no progeny. KALRO looking forward to develop mass rearing facility for fruit flies and SIT facility

  5. Tunisian Rearing facility a first year production constraints and prospects

    International Nuclear Information System (INIS)

    Guerfali, M.M; Ben Salah, H.; Caceres, C.; Raies, A.

    2005-01-01

    The Tunisian Medfly rearing facility is located in the north of the country in a small city named Sidi Thabet, near the capital. This facility was designed for rearing the Medfly Genetic Sexing strain (GSS). The facility has been started operations in 2003 in order to release sterile males under 6000 hectares in the north east of the country in the Cap Bon Peninsula. This programme is supported by the Tunisian government, IAEA and FAO. Male only production was not stable for the four first months, due to some constraints. The production is stabilising by the time, after the tune fine off all rearing procedures and adjustment of the environmental control system. Quality control procedures (QC) were put for each procedure of the production from eggs to adult following the procedures established in the International FAO/IAEA/USDA Fruit Flies Quality control Manual

  6. Genetic basis of the sterile insect technique

    International Nuclear Information System (INIS)

    Robinson, A.S.

    2005-01-01

    The use of the sterile insect technique (SIT) for insect control relies on the introduction of sterility in the females of the wild population. This sterility is produced following the mating of these females with released males carrying, in their sperm, dominant lethal mutations that have been induced by ionizing radiation. The reasons why the SIT can only be effective when the induced sterility in the released males is in the form of dominant lethal mutations, and not some form of sperm inactivation, are discussed, together with the relationship of dominant lethal mutations to dose, sex, developmental stage and the particular species. The combination of genetic sterility with that induced by radiation is also discussed in relation to the use of genetic sexing strains of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) in area-wide integrated pest management (AW-IPM) programmes that integrate the SIT. A case is made to lower the radiation dose used in such programmes so as to produce a more competitive sterile insect. Increased competitiveness can also be achieved by using different radiation environments. As well as radiation-induced sterility, natural mechanisms can be recruited, especially the use of hybrid sterility exemplified by a successful field trial with tsetse flies Glossina spp. in the 1940s. Genetic transformation will make some impact on the SIT, especially regarding the introduction of markers for released flies, and the construction of genetic sexing strains. It is concluded that using a physical process, such as radiation, will always have significant advantages over genetic and other methods of sterilization for the large-scale application of the SIT. (author)

  7. Studies on the ecology of insects sterilized artificially (gamma radiation), 7

    International Nuclear Information System (INIS)

    Kiyoku, Masao; Tsukuda, Ritsuko

    1974-01-01

    Larvae of an oriental fruit fly line introduced, from Amami-Oshima island were reared using an artificial medium prepared with the base ingredient as corn-flour. When pupae were irradiated with a dose of 8 kR from the 137 Cs as gamma-rays source two days before emerging, both male and female adults emerged showed complete sterility. Percentage in emergence, however, was not significantly reduced. In an experiment that two hundred sterilized plus ten normal males were confined with ten normal females in a mating cage, the sterilized males were fully competitive with normal ones in mating to the normal females. Longevity of the sterilized adult males, however, tended to be slightly shorter than that of the normal ones when compared in the survival curves. When less than one hundred and fifty sterilized males were confined, however, few larvae were able to grow to adults. These progeny adult males and females showed the inherited sterility. When dose was 6 kR there was neither significant difference in the longevity between sterilized and normal adults, nor the complete sterility. Besides, the inherited sterility in offspring was not shown clearly. When more than two hundred sterilized plus ten normal males were combined with ten normal females, however, a considerable sterility was found. Causes of the sterility were investigated by dissection of the testes and spermathecae in females mated with 8 kR-sterilized males. (author)

  8. Cosmology seeking friendship with sterile neutrinos

    International Nuclear Information System (INIS)

    Hamann, J.; Hannestad, S.; Raffelt, G.G.; Tamborra, I.; Wong, Y.Y.Y.

    2011-01-01

    Precision cosmology and big-bang nucleosynthesis mildly favour extra radiation in the universe beyond photons and ordinary neutrinos, lending support to the existence of low-mass sterile neutrinos. We present bounds on the common mass scale ms and effective number Ns of thermally excited sterile neutrino states from the most recent cosmological data. Our results are compatible with the existence of one or perhaps two sterile neutrinos, as suggested by LSND and MiniBooNE, if ms is in the sub-eV range.

  9. Mass rearing of the Mexican fruit fly, Anastrepha ludens, at the Fruit Flies Biofactory in Metapa de Dominguez, Chiapas, Mexico

    International Nuclear Information System (INIS)

    Zavala Lopez, J.L.; Dominguez G, J.; Gomez S, Y.; Moreno, P.

    1999-01-01

    A description of the present methods for mass rearing Anastrepha ludens, known as the Mexican fruit fly, at the Fruit Flies Biofactory in Metapa de Dominguez, Chiapas, is given. Important contributions and improvements are described for the rearing stages, e.g. egg production and incubation, larvae diets, lab conditions for the development of larvae and pupae, larvae and pupae handling and environmental control. (author)

  10. Sterile neutrinos as dark matter

    International Nuclear Information System (INIS)

    Dodelson, S.; Widrow, L.M.

    1994-01-01

    The simplest model that can accommodate a viable nonbaryonic dark matter candidate is the standard electroweak theory with the addition of right-handed (sterile) neutrinos. We consider a single generation of neutrinos with a Dirac mass μ and a Majorana mass M for the right-handed component. If M much-gt μ (standard hot dark matter corresponds to M=0), then sterile neutrinos are produced via oscillations in the early Universe with energy density independent of M. However, M is crucial in determining the large scale structure of the Universe; for M∼100 eV, sterile neutrinos make an excellent warm dark matter candidate

  11. The Mediterranean fruit fly in Central America

    International Nuclear Information System (INIS)

    Vail, V.; Moore, I.; Nadel, D.

    1976-01-01

    Various methods of controlling the medfly are available and include the use of insecticides, bait sprays and the sterile insect technique (SIT). Each of these control strategies may be used alone or in sequence. With regard to the application of the SIT, the Joint FAO/IAEA Division of Atomic Energy in Food and Agriculture through its Insect and Pest Control Section and Entomology Laboratory is in an excellent position to assist in containing the medfly in Central America. For the past 12 years, the laboratory has participated in all phases of medfly control by sterile insect releases in various climates. This involvement has included planning of medfly campaigns, development of pre-release techniques (bait spraying, trapping, etc.) and shipment and release of sterilized medflies. Small-scale field tests utilizing the SIT have been carried out by nine countries: Italy (Procida, Capri), Spain, Cyprus, Israel, Tunisia, Peru, Panama, Costa Rica and Nicaragua. Other field projects presently being counselled and serviced are located in Argentina, Venezuela and the Canary Islands. The research and development that are still needed to effectively stabilize and gain control of the medfly situation in Central America include: The development and use of effective quarantine procedures in various countries; Development of effective conventional medfly control procedures under the conditions found in Central America; Development of methods to determine the geographic origin of medflies introduced into new areas; Medfly mass production (viz. all aspects of rearing Central American strains); Assessing the performance (competitiveness, etc.) of various strains; Logistics, including the development of systems for releasing pre-adult stages; Genetic rearing methods: developmental research in this area is particularly promising since the preferential production of males would allow considerable savings in the rearing costs of medflies for release; Development of adequate surveillance

  12. Efficacy of Blood Sources and Artificial Blood Feeding Methods in Rearing of Aedes aegypti (Diptera: Culicidae) for Sterile Insect Technique and Incompatible Insect Technique Approaches in Sri Lanka.

    Science.gov (United States)

    Gunathilaka, Nayana; Ranathunge, Tharaka; Udayanga, Lahiru; Abeyewickreme, Wimaladharma

    2017-01-01

    Selection of the artificial membrane feeding technique and blood meal source has been recognized as key considerations in mass rearing of vectors. Artificial membrane feeding techniques, namely, glass plate, metal plate, and Hemotek membrane feeding method, and three blood sources (human, cattle, and chicken) were evaluated based on feeding rates, fecundity, and hatching rates of Aedes aegypti . Significance in the variations among blood feeding was investigated by one-way ANOVA, cluster analysis of variance (ANOSIM), and principal coordinates (PCO) analysis. Feeding rates of Ae. aegypti significantly differed among the membrane feeding techniques as suggested by one-way ANOVA ( p feeding technique. Blood feeding rate of Ae. aegypti was higher with human blood followed by cattle and chicken blood, respectively. However, no significant difference was observed from the mosquitoes fed with cattle and human blood, in terms of fecundity, oviposition rate, and fertility as suggested by one-way ANOVA ( p > 0.05). Metal plate method could be recommended as the most effective membrane feeding technique for mass rearing of Ae. aegypti , due to its high feeding rate and cost effectiveness. Cattle blood could be recommended for mass rearing Ae. aegypti .

  13. Genes for genetic sexing in the Mediterranean fruit fly, Ceratitis capitata (Wied.), and the mosquito, Anopheles stephensi

    International Nuclear Information System (INIS)

    Robinson, A.S.

    1990-01-01

    A system was developed utilizing alcohol dehydrogenase (ADH) that produced only male medflies. High sterility in the line plus male mortality from the treatment made the system unsuitable for genetic sexing on a large scale. A strain of Anopheles stephensi was developed in which females could be killed by dieldrin, but males survived. A large field cage release of medfly sexed by colour in the pupal stage demonstrated the advantages of male-only releases. The pupal colour sexing strain broke down under mass rearing. (author). 19 refs, 1 fig., 6 tabs

  14. Biological and Cultural Control of Olive Fruit Fly in California---Utilization of Parasitoids from USDA-APHIS-PPQ, Guatemala

    Science.gov (United States)

    The parasitoid Psytallia cf. concolor (Szépligeti) was reared on sterile Mediterranean fruit fly larvae at the USDA-APHIS-PPQ, Petapa Quarantine Laboratory in Guatemala and shipped to the USDA-ARS, Parlier, for wide-spread release and biological control of olive fruit fly in California. As many as 3...

  15. Limited mobility of target pests crucially lowers controllability when sterile insect releases are spatiotemporally biased.

    Science.gov (United States)

    Ikegawa, Yusuke; Himuro, Chihiro

    2017-05-21

    The sterile insect technique (SIT) is a genetic pest control method wherein mass-reared sterile insects are periodically released into the wild, thereby impeding the successful reproduction of fertile pests. In Okinawa Prefecture, Japan, the SIT has been implemented to eradicate the West Indian sweet potato weevil Euscepes postfasciatus (Fairmaire), which is a flightless agricultural pest of sweet potatoes. It is known that E. postfasciatus is much less mobile than other insects to which the SIT has been applied. However, previous theoretical studies have rarely examined effects of low mobility of target pests and variation in the spatiotemporal evenness of sterile insect releases. To theoretically examine the effects of spatiotemporal evenness on the regional eradication of less mobile pests, we constructed a simple two-patch population model comprised of a pest and sterile insect moving between two habitats, and numerically simulated different release strategies (varying the number of released sterile insects and release intervals). We found that spatially biased releases allowed the pest to spatially escape from the sterile insect, and thus intensively lowered its controllability. However, we showed that the temporally counterbalancing spatially biased releases by swapping the number of released insects in the two habitats at every release (called temporal balancing) could greatly mitigate this negative effect and promote the controllability. We also showed that the negative effect of spatiotemporally biased releases was a result of the limited mobility of the target insect. Although directed dispersal of the insects in response to habitats of differing quality could lower the controllability in the more productive habitat, the temporal balancing could promote and eventually maximize the controllability as released insects increased. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Large scale artificial rearing of Anastrepha sp.1 aff. fraterculus (Diptera: Tephritidae in Brazil

    Directory of Open Access Journals (Sweden)

    Julio Marcos Melges Walder

    2014-08-01

    Full Text Available Some species of the genus Anastrepha (Diptera: Tephritidae are successfully managed by matching the sterile insect technique with parasitoid releases. Such strategies used in integrated pest management can be implemented only where insect mass-rearing programs are feasible. In this study, we show the process of domestication, rearing technology and quality control data obtained from 54 generations of Anastrepha sp.1 aff. fraterculus (Wiedemann, 1830 kept under fully artificial conditions. Eggs were collected by an artificial oviposition panel consisting of one side of the cage made of blue voile fabric externally covered with a thin layer of silicon rubber. They were then air-bubbled in water at 25 ºC for 48 h before seeding. Larvae were reared on the regular laboratory artificial diet with 66 % of agar reduction turning over a semi-liquid diet, which reduced costs and improved insect quality. The adult and larval diets were composed of local ingredients including hydrolyzed yeast. When large-scale production of this fly is contemplated, the critical stage is larval development. This system of artificial rearing for A. fraterculus sp.1 developed in Brazil, allows for the production of a large number of insects of excellent quality using local ingredients and less agar in diet composition than the original medium used for this species. By reducing the interval of egg collection, the system might be optimized in terms of insect yield and, therefore, meet the demands of A. fraterculus sp.1 with regard to integrated pest management purposes.

  17. Impediment to Symbiosis Establishment between Giant Clams and Symbiodinium Algae Due to Sterilization of Seawater

    Science.gov (United States)

    Kurihara, Takeo; Yamada, Hideaki; Inoue, Ken; Iwai, Kenji; Hatta, Masayuki

    2013-01-01

    To survive the juvenile stage, giant clam juveniles need to establish a symbiotic relationship with the microalgae Symbiodinium occurring in the environment. The percentage of giant clam juveniles succeeding in symbiosis establishment (“symbiosis rate”) is often low, which is problematic for seed producers. We investigated how and why symbiosis rates vary, depending on whether giant clam seeds are continuously reared in UV treated or non treated seawater. Results repeatedly demonstrated that symbiosis rates were lower for UV treated seawater than for non treated seawater. Symbiosis rates were also lower for autoclaved seawater and 0.2-µm filtered seawater than for non treated seawater. The decreased symbiosis rates in various sterilized seawater suggest the possibility that some factors helping symbiosis establishment in natural seawater are weakened owing to sterilization. The possible factors include vitality of giant clam seeds, since additional experiments revealed that survival rates of seeds reared alone without Symbiodinium were lower in sterilized seawater than in non treated seawater. In conclusion, UV treatment of seawater was found to lead to decreased symbiosis rates, which is due possibly to some adverse effects common to the various sterilization techniques and relates to the vitality of the giant clam seeds. PMID:23613802

  18. Reproductive behavior and physiology of Dacus oleae: egg hatch in females mated successively with normal and gamma sterilized males and vice versa

    International Nuclear Information System (INIS)

    Economopoulos, A.P.; Giannakakis, A.; Voyadjoglou, A.V.

    1976-01-01

    In Dacus oleae (Gmelin), a 2nd mating by an 8-krad gamma ray-sterilized male reduced egg hatch immediately to zero or near-zero in ca. 40-55 percent of individually-tested females. In another 50 percent of females, egg hatch was reduced to between 5 to 70 percent, while in fewer than 10 percent of females, egg hatch showed no change. The above was true for females reared on artificial diet for more than 50 generations and mated with same type males, as well as females reared on olives for 6 to 8 generations and mated first with same type males and 2nd with artificially-reared sterilized males. When the 2nd males were treated at 15 krad the effect on egg hatch was smaller. When the 2nd males were treated at 8 krad and had depleted their sperm, by repeated matings, they produced small or no-effect on egg hatch. When artificially-reared females mated first with a sterilized and second with a normal same type male, egg hatch increased from 0 to 5 percent to 70 to 100 percent in 50 to 55 percent of the cases. In another 43 percent of cases, egg hatch increased to levels between 5 to 70 percent. The combined findings from the 2 mating sequence types are as follows. After females mated first with normal males, egg hatch was above 80 percent in the population; a 2nd mating with 8-krad-sterilized males produced an immediate decrease of egg hatch to ca. 25 percent, decreasing slowly thereafter. When the 1st male was sterilized and the 2nd normal, egg hatch increased to ca. 70 percent, decreasing slowly thereafter

  19. Modelling Aedes aegypti mosquito control via transgenic and sterile insect techniques: Endemics and emerging outbreaks

    KAUST Repository

    Seirin Lee, S.

    2013-08-01

    The invasion of pest insects often changes or destroys a native ecosystem, and can result in food shortages and disease endemics. Issues such as the environmental effects of chemical control methods, the economic burden of maintaining control strategies and the risk of pest resistance still remain, and mosquito-borne diseases such as malaria and dengue fever prevail in many countries, infecting over 100 million worldwide in 2010. One environmentally friendly method for mosquito control is the Sterile Insect Technique (SIT). This species-specific method of insect control relies on the mass rearing, sterilization and release of large numbers of sterile insects. An alternative transgenic method is the Release of Insects carrying a Dominant Lethal (RIDL). Our objective is to consider contrasting control strategies for two invasive scenarios via SIT and RIDL: an endemic case and an emerging outbreak. We investigate how the release rate and size of release region influence both the potential for control success and the resources needed to achieve it, under a range of conditions and control strategies, and we discuss advantageous strategies with respect to reducing the release resources and strategy costs (in terms of control mosquito numbers) required to achieve complete eradication of wild-type mosquitoes. © 2013 Elsevier Ltd.

  20. Modelling Aedes aegypti mosquito control via transgenic and sterile insect techniques: Endemics and emerging outbreaks

    KAUST Repository

    Seirin Lee, S.; Baker, R.E.; Gaffney, E.A.; White, S.M.

    2013-01-01

    The invasion of pest insects often changes or destroys a native ecosystem, and can result in food shortages and disease endemics. Issues such as the environmental effects of chemical control methods, the economic burden of maintaining control strategies and the risk of pest resistance still remain, and mosquito-borne diseases such as malaria and dengue fever prevail in many countries, infecting over 100 million worldwide in 2010. One environmentally friendly method for mosquito control is the Sterile Insect Technique (SIT). This species-specific method of insect control relies on the mass rearing, sterilization and release of large numbers of sterile insects. An alternative transgenic method is the Release of Insects carrying a Dominant Lethal (RIDL). Our objective is to consider contrasting control strategies for two invasive scenarios via SIT and RIDL: an endemic case and an emerging outbreak. We investigate how the release rate and size of release region influence both the potential for control success and the resources needed to achieve it, under a range of conditions and control strategies, and we discuss advantageous strategies with respect to reducing the release resources and strategy costs (in terms of control mosquito numbers) required to achieve complete eradication of wild-type mosquitoes. © 2013 Elsevier Ltd.

  1. Practical application of insect-parasitic nematodes and sterile flies; Praktische Anwendung insektenparasitischer Nematoden und sterilisierter Fliegen

    Energy Technology Data Exchange (ETDEWEB)

    Galle, F. [Bayerisches Staatsministerium fuer Ernaehrung, Landwirtschaft und Forsten, Muenchen (Germany); Loosjes, M. [De Groene Vlieg, Nieuwe Tonge (Netherlands)

    1987-07-01

    The company 'de Groene Vlieg' started with commercial control of the onion fly by means of the sterile insect technique. At the moment 10 per cent of the Dutch spring sown onions are treated with this method. The mass-rearing, the estimations of populations and the repeated releases of sterilized flies make it a rather complicated method. It can be applied economically per field, but only in areas with a concentration of onion growing. For export we see no possibilities yet. In principle the sterile insect technique can be applied also to other flies (carrot rust fly, cabbage root fly), but a suitable artificial diet is still lacking. Since some years we also rear the insect parasitic nematodes Heterorhabditis sp. and Neoaplectana bibionis. The later is experimentally used with success against Agrotis segetum caterpillars in lettuce. Research will yield more applications of nematodes against different pests. We use Heterorhabditis sp. in practice against the black vine weevil (Otiorhynchus sulcatus), a serious pest in glass houses, tree nurseries and gardens. Good control is achieved with a dose of one half to one million nematodes per square meter in moist soil and with temperatures above 12 degrees C. The application is similar to that of a chemical insecticide. The pest is killed by symbiontic bacteria, released by the nematodes after penetrating into the body cavity of the larvae. The nematodes are delivered by mail. If cooled they can be kept alive for over four weeks in the package. We export already to Switzerland and plan to export also to Western Germany. At this moment a possible admittance is under investigation in the Netherlands for application of a nuclear polyhedrosis virus against Spodoptera exigua caterpillars.

  2. Monitoring sterile and wild insects in area-wide integrated pest management programmes

    International Nuclear Information System (INIS)

    Vreysen, M.J.B.

    2005-01-01

    Insect pest control programmes, which integrate the release of sterile insects, can be efficient only if the released insects have an optimal biological quality. Frequent monitoring of the quality of reared insects after being released in the field is an important but often neglected component of area-wide integrated pest management (AW-IPM) programmes that integrate the sterile insect technique (SIT). Parameters of sterile insects, which should be monitored regularly, are sexual competitiveness of the released insects, and related components, e.g. survival, mobility, dispersal characteristics, and spatial occupation of the habitat. A well-balanced monitoring programme will, at any given time, provide essential feedback on the progress being made. This information is prerequisite to efficient implementation of the release and cost-efficient use of sterile insects. The type of monitoring to be done will be determined largely by the particular biology of the target insect species. The most important parameter in relation to the release of sterile insects is the rate of sterility induced in the wild insect pest population; it will provide the best evidence that any observed changes, e.g. in the density of the target insect, are caused by the release of sterile insects. (author)

  3. Determination of the dose of gamma radiation sterilization for assessment of biological parameters of male Ceratitis capitada (Diptera: Tephritidae), tsl - Vienna 8 strain

    International Nuclear Information System (INIS)

    Rocha, Aline Cristina Pereira da

    2011-01-01

    The Vienna-8, tsl (temperature sensitive lethal) strain of Ceratitis capitata, by presenting mutations that facilitate the mass rearing and release only of sterile males in the field, has been used in (Sterile Insect Technique) programmes. The objective of this study was to determine the radiation dose that provides the highest level of sterility for Vienna-8, tsl males assessing their biological parameters that indicate the quality of sterile males to be released. Brown pupae (males) of the tsl strain were obtained from the mass rearing of the Food Irradiation and Radio entomology laboratory of CENA/USP, and they were irradiated (with gamma radiation - 60 Co) 24 hours before the emergence at rates of 0, 30, 60, 90 and 120 Gy. The determination of the sterilizing dose was based on fertility of sexually mature females of the bisexual strain and not irradiated, mated with males of different treatments. Eggs were collected daily during 6 days, were counted and it was possible to estimate fecundity, and assess the hatching rate. The emergence and flight ability were determined by following the protocol of quality control manual for FAO/IAEA/USDA (2003). To assess the longevity under nutritional stress, the insects were kept a period of 48 h after emergence in the absence of water and food, and after this period, mortality was recorded. The size of the testes (left and right) was obtained by dissecting irradiated and non-irradiated males at the eighth day of life, and measure the testes in an ocular micrometer, considering the maximum length and width of each sample. To determine the sperm number was necessary to dissect the males and break their testicles. No difference was observed in emergence rate, flight ability and longevity of irradiated and non-irradiated males, nor in the fecundity of females mated with males of different treatments. The sterilizing dose that resulted in lower fertility of females was 120 Gy, with 1.5% hatching. Considering the parameters of

  4. Body mass dynamics in hand reared clouded leopard (Neofelis nebulosa) cubs from birth to weaning.

    Science.gov (United States)

    Nájera, Fernando; Brown, Janine; Wildt, David E; Virolle, Laurie; Kongprom, Urarikha; Revuelta, Luis; Goodrowe-Beck, Karen

    2015-01-01

    To study the dynamics of body mass changes in hand reared clouded leopards, we analyzed 3,697 weight data points during the first 3 months of life in 49 cubs from 24 zoo-born litters from 2003 through 2012. All cubs were fed the same formula mixture after a similar weaning protocol. The hand rearing process was divided into three periods based on feeding protocols: Stage 1: formula only (Days 1-28; Day 0 = day of birth); Stage 2, formula supplemented with protein (e.g., turkey baby food; Days 29-42); Stage 3, formula in decreasing amounts supplemented with meat (chicken and/or beef; Days 43-90). Weights at birth were 11.2% higher (P weight gain was slowest (P  0.05) growth and weaning weights compared to healthy counterparts. These are the first data documenting, on a large scale, the growth patterns for zoo born, hand reared clouded leopard cubs. Findings are valuable as an aid in managing this rare species, including for helping identify early onset of medical issues and further determining key factors regulating the first 3 months of development. © 2015 Wiley Periodicals, Inc.

  5. Sterilization experiment of crocidolomia binotalis zeller by gamma ray irradiation and its control application

    International Nuclear Information System (INIS)

    Sutrisno, Singgih

    1986-01-01

    Experiments have been conducted to study C. binotalis control initiated with the rearing method and ended with the release of sterile irradiated insects. Rearing of cabbage pest using modified artificial diet of Pieris rapae gave better result compared to that with natural diet. The larval viability was 58% and 25.9% from the artificial and the natural diet respectively. Gamma ray doses of 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4 and 0.45 kGy were introduced to six-day-old sexed pupae in nitrogen and air atmosphere. A 100% sterility on males was obtained at 0.45 kGy in both air and nitrogen atmosphere. 100% sterility on females was found at 0.25 kGy in nitrogen and 0.2 kGy in air atmosphere. The effect of dose on the percentage of sterile and mating competitiveness were not significantly different (P ≥0.05). A significant correlation (r=0.8774) was found between the percentage of fertility and the mating competitiveness of irradiated insects. The lower the fertility of the insects the less mating competitiveness they have. 0.4 kGy was considered to be adequate for sterilization of C. binotalis. It produced a high percentage of sterility besides moderate mating competitiveness, 84.52% and 0.57% respectively. 0.4 kGy seemed to give 3 days shorter longevity of moth than the normal one. The number of F 1 larval population was not significantly different if the released insects were either females or males or mixed sexes. The ratio of 9:1 of the sterile and normal insects under laboratory, field-cage, and in the field indicated that the sterile insect technique has the potential to suppress F 1 population by about 50% due to the mating competitiveness of the radiosterilized insect still maintained at the level of 0.57. (author). 17 refs

  6. Cotton bollworm, Helicoverpa armigera (Lepidoptera: Noctuidae): Large scale rearing and the effect of gamma radiation on selected life history parameters of this pest in China

    International Nuclear Information System (INIS)

    Lu Daguang; Liu Xiaohui; Hu Jiangguo; Wang Endong; He Qiulan; Li Yongjun

    2002-01-01

    Effective large scale rearing of the cotton bollworm, Helicoverpa armigera (Huebner), has been developed in China. A 'celled unit' system was developed to replace the traditional test tube for cotton bollworm laboratory rearing. Larvae are reared at 26.5 deg. C, ∼ 70% RH, and a long day photoperiod of 14L:10D. Pupae are harvested at about day 20. Percent adult emergence is between 89-93%, and adult females lay an average of 768 eggs. Under this rearing system one generation is completed in 40-42 days and percent pupation is about 66-71%. Mature Helicoverpa armigera female and male pupae were treated with different doses of gamma radiation and out-crossed with untreated mates. Mating ability of both sexes was not affected by radiation. Treated females were highly sterile and laid significantly fewer eggs than untreated controls. Females treated with 300 Gy were completely sterile, while females treated with 250 Gy and 200 Gy still had minimal residual fertility. (author)

  7. Applying the sterile insect technique to the control of insect pests

    International Nuclear Information System (INIS)

    LaChance, L.E.; Klassen, W.

    1991-01-01

    The sterile insect technique (SIT) is basically a novel twentieth century approach to insect birth control. It is species specific and exploits the mate seeking behaviour of the insect. The basic principle is simple. Insects are mass reared in 'factories' and sexually sterilized by gamma rays from a 60 Co source. The sterile insects are then released in a controlled fashion into nature. Matings between the sterile insects released and native insects produced no progeny. If enough of these matings take place, reproduction of the pest population decreases. With continued release, the pest population can be controlled and in some cases eradicated. In the light of the many important applications of the SIT worldwide and the great potential that SIT concepts hold for insect and pest control in developing countries, two special benefits should be stressed. Of greatest significance is the fact that the SIT permits suppression and eradication of insect pests in an environmentally harmless manner. It combines nuclear techniques with genetic approaches and, in effect, replaces intensive use of chemicals in pest control. Although chemicals are used sparingly at the outset in some SIT programmes to reduce the size of the pest population before releases of sterilized insects are started, the total amount of chemicals used in an SIT programme is a mere fraction of what would be used without the SIT. It is also of great importance that the SIT is not designed strictly for the eradication of pest species but can readily be used in the suppression of insect populations. In fact, the SIT is ideally suited for use in conjunction with other agricultural pest control practices such as the use of parasites and predators, attractants and cultural controls (e.g. ploughing under or destruction of crop residues) in integrated pest management programmes to achieve control at the lowest possible price and with a minimum of chemical contamination of the environment

  8. Applying the sterile insect technique to the control of insect pests

    Energy Technology Data Exchange (ETDEWEB)

    LaChance, L E; Klassen, W [Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Vienna (Austria)

    1991-09-01

    The sterile insect technique (SIT) is basically a novel twentieth century approach to insect birth control. It is species specific and exploits the mate seeking behaviour of the insect. The basic principle is simple. Insects are mass reared in 'factories' and sexually sterilized by gamma rays from a {sup 60}Co source. The sterile insects are then released in a controlled fashion into nature. Matings between the sterile insects released and native insects produced no progeny. If enough of these matings take place, reproduction of the pest population decreases. With continued release, the pest population can be controlled and in some cases eradicated. In the light of the many important applications of the SIT worldwide and the great potential that SIT concepts hold for insect and pest control in developing countries, two special benefits should be stressed. Of greatest significance is the fact that the SIT permits suppression and eradication of insect pests in an environmentally harmless manner. It combines nuclear techniques with genetic approaches and, in effect, replaces intensive use of chemicals in pest control. Although chemicals are used sparingly at the outset in some SIT programmes to reduce the size of the pest population before releases of sterilized insects are started, the total amount of chemicals used in an SIT programme is a mere fraction of what would be used without the SIT. It is also of great importance that the SIT is not designed strictly for the eradication of pest species but can readily be used in the suppression of insect populations. In fact, the SIT is ideally suited for use in conjunction with other agricultural pest control practices such as the use of parasites and predators, attractants and cultural controls (e.g. ploughing under or destruction of crop residues) in integrated pest management programmes to achieve control at the lowest possible price and with a minimum of chemical contamination of the environment.

  9. Rearing Technique, Biology and Sterilization of the Coffee Leaf Miner, Leucoptera Coffeella Guer. (Lepidoptera: Lyonetiidae)

    Energy Technology Data Exchange (ETDEWEB)

    Katiyar, K. P.; Ferrer, F. [Inter-American Institute of Agricultural Sciences of the OAS Training and Research Center, Turrialba (Costa Rica)

    1968-06-15

    For two years the authors studied the feasibility of controlling the coffee leaf miner Leucoptera coffeella Guer. by the radiation sterilization technique. During this period a technique for raising large numbers of tills insect on potted coffee plants in the laboratory was devised. The optimal range for the development of egg, larval and pupal stages of the coffee leaf miner was between 20 and 30 Degree-Sign C. The pupal stage of female insects was slightly shorter than that of the male. The laying of fertile eggs began during the first night following emergence. During an oviposition period of 16 days the average fecundity was 68 eggs. The maximum oviposition by a single female was 131 eggs over the life span while as many as 34 eggs were laid during a single day of oviposition. To investigate the best stage to induce radiation sterilization, pupal and adult insects were irradiated with {sup 60}CO gamma rays. Seven-day pupae (close to emergence) showed 88% lethality in males when given 60 krad; the survivors retained some fertility. Adult females receiving 70 krad were 100% sterile while males given 90 krad showed 0.02% fertility. Doses as high as 90 krad given to newly emerged adults did not reduce longevity. Studies are continuing to determine if sterilizing doses impair sexual vigour and mating competitiveness of the treated males. (author)

  10. The influence of rearing medium on the irradiation sensitivity of eggs and larvae of the flour beetle, Tribolium confusum J. du Val

    International Nuclear Information System (INIS)

    Tunçbilek, A.Ş.; Kansu, I.A.

    1996-01-01

    In this study, gamma radiation was applied at six dose levels over the range of 5–40 Gy for 0–2-day-old eggs, and at eight dose levels between 10–80 Gy for 16–18-day-old larvae of Tribolium confusum. Sterility, mortality and other effects of gamma radiation were investigated. All experiments were performed in incubators maintained at 27 ± 0.5 °C and 70 ± 5% r.h. The development of adults reared on different flours from irradiated eggs and larvae was prevented by exposure to 40 and 50 Gy of gamma radiation, respectively. Rate of development of these stages on different flours and the yield of adults was influenced by rearing medium. Rapidly developing flour beetles are more susceptible to killing by gamma radiation. For each stage reared on different media (wheat, barley and maize flours), LD50 and LD99.9 values were determined, together with sterilizing dose levels (SD50 and SD99.9)

  11. The influence of rearing medium on the irradiation sensitivity of eggs and larvae of the flour beetle, Tribolium confusum J. du Val

    International Nuclear Information System (INIS)

    Tunçbilek, Aydin Ş.; Kansu, I.A.

    1996-01-01

    In this study, gamma radiation was applied at six dose levels over the range of 5–40 Gy for 0–2-day-old eggs, and at eight dose levels between 10–80 Gy for 16–18-day-old larvae of Tribolium confusum. Sterility, mortality and other effects of gamma radiation were investigated. All experiments were performed in incubators maintained at 27 ± 0.5 °C and 70 ± 5% r.h. The development of adults reared on different flours from irradiated eggs and larvae was prevented by exposure to 40 and 50 Gy of gamma radiation, respectively. Rate of development of these stages on different flours and the yield of adults was influenced by rearing medium. Rapidly developing flour beetles are more susceptible to killing by gamma radiation. For each stage reared on different media (wheat, barley and maize flours), LD 50 and LD 99.9 values were determined, together with sterilizing dose levels (SD 50 and SD 99.9 ). (author)

  12. Guide for dosimetry for sterile insect release programs. 2. ed.

    International Nuclear Information System (INIS)

    2004-01-01

    This guide outlines dosimetric procedures to be followed for the radiation sterilization of live insects for use in pest management programs. The primary use of irradiated, reproductively sterile insects is in the Sterile Insect Technique, where large numbers of sterile insects are released into the field to mate with and thus control pest populations of the same species. A secondary use of sterile insects is as benign hosts for rearing insect parasitoids. The procedures outlined in this guide will help ensure that insects processed with ionizing radiation from gamma, electron, or X-ray sources receive absorbed doses within a predetermined range. Information on effective dose ranges for specific applications of insect sterilization, or on methodology for determining effective dose ranges, is not within the scope of this guide. Note: Dosimetry is only one component of a total quality control program to ensure that irradiated insects are adequately sterilized and sufficiently competitive or otherwise suitable for their intended purpose. This guide covers dosimetry in the irradiation of insects for these types of irradiators: self-contained dry-storage 137 Cs or 60 Co irradiators, large-scale gamma irradiators, and electron accelerators. Additional, detailed information on dosimetric procedures to be followed in installation qualification, operational qualification, performance qualification, and routine product processing can be found in ISO/ASTM Practices 51608 (X-ray [bremsstrahlung] facilities), 51649 (electron beam facilities), 51702 (large-scale gamma facilities), and ASTM Practice E 2116 (self-contained dry-storage gamma facilities). The absorbed dose for insect sterilization is typically within the range of 20 Gy to 600 Gy

  13. Laboratory and field evaluation of sterile male boll weevil competitiveness

    International Nuclear Information System (INIS)

    McGovern, W.L.

    1976-01-01

    The production of pheromone by boll weevils, Anthonomus grandis Boheman, treated with 10,000 rad of CO-60 gamma irradiation compared favorably with that of control weevils for 5 days; however, feeding (determined by frass collection) was reduced from the first day post-treatment. No direct correlation was found between production of pheromone and elimination of frass. Overwintered male boll weevils were found to produce small quantities of pheromone and the ratio of components was less attractive at the same concentration as the standard laboratory formulation of grandlure. Most healthy sterilized male weevils should be more attractive than overwintered males. Laboratory-reared sterilized male boll weevils can be as attractive to female weevils as overwintered field males. Weevils treated with busulfan (1,4-butanediol dimethanesulfonate) alone were more attractive than those treated with combinations of busulfan and hempa. In general, sterilization reduced the attractiveness of laboratory males by about 50 percent. Evidence is presented for the existence of ''super-males.''

  14. Factors influencing sterility and vitality of the Mediterranean fruit fly, Ceratitis capitata Wiedemann

    Energy Technology Data Exchange (ETDEWEB)

    Wakid, A M; Amin, A H; Shoukry, A; Fadel, A [Atomic Energy Establishment, Cairo (Egypt)

    1982-01-01

    Males of Ceratitis capitata Wied. previously reared on three different larval media (molasses, sugar and glucose) were irradiated as old pupae with 7, 9 and 11 krad of gamma radiation. Results indicated that egg hatchability and male survival did not differ significantly in the three media at the three applied doses. Mating competitiveness of 9 krad-irradiated males at the ratio 3:1:1 (irradiated males : normal males : normal females) did not differ when using the different larval diets. When pupae were irradiated with the three doses, each given at three different dose rates, i.e. 7, 30 and 97 rad/s, a gradual decrease in egg hatchability was observed as the dose rate was increased. Adult survival was not affected by differences in either dose rate or in the radiation dose. Mating competitiveness of 9 krad-irradiated males was not affected by changes in dose rate. Old pupae were irradiated with 9 krad in three fractions at one-day interval between each treatment. Egg hatchability, male survival and male competitiveness did not differ significantly from those obtained when the dose was given in one treatment. Pupal incubation at different temperatures for two hours or two days did not affect egg hatchability in the non-irradiated group. On the other hand, pupal incubation at both 5/sup 0/ or 15/sup 0/C either for two hours or two days prior to irradiation resulted generally in a significant reduction in the percentages of sterility compared with 25/sup 0/C. Practically, there was no effect on male survival of either the temperature or the incubation period to which the pupae were exposed prior to irradiation. However, the male competitiveness was better when the pupae were incubated at 5/sup 0/ or 15/sup 0/C for two days rather than for two hours.

  15. Multiple matings among glossina and the sterile male technique

    International Nuclear Information System (INIS)

    Pinhao, R.C.

    1980-01-01

    The fact that multiple matings are a common phenomenon among glossina turns the sterile male technique into a competition not between adult insects but between two types of sperm, and the proportion of females inseminated with the one or the other is given by the binomial (p+q)sup(n), where p is the percentage of normal males, q the percentage of sterile males and n the average number of matings per female. However, multiple matings cannot damage the effectiveness of the technique unless two conditions are present either separately or simultaneously: precocious death of the spermatozoa and reduced inseminating potential among the sterile males. Study of the factors which can alter the inseminating potential is thus important for those who wish to use the sterile male technique. These factors are of three kinds: factors connected with quality, with quantity and with availability. The first are associated with the nature and intensity of the alterations brought about in the spermatozoa by the sterilizing agent, the second with possible variations in the amount of sperm reaching the spermotheca, the third with the behaviour of the sterile males in the nature - that is, the question whether sterilization has a favourable or unfavourable influence on their chances of mating with wild females. The author describes his observations of the quantity of sperm produced by Glossina morsitans submorsitans males from the colony reared at the Institute for Tropical Hygiene and Medicine in Lisbon, compares them with the observations of other authors and discusses their practical significance. Specific research is suggested. Advantages from assessing the behaviour of colonies not by female productivity but by male inseminating potential, and appropriate laboratory techniques

  16. Sterile medfly males of the tsl Vienna 8 genetic sexing strain display improved mating performance with ginger root oil

    International Nuclear Information System (INIS)

    Paranhos, Beatriz Jordao; Alves, Renata Morelli; McInnis, Donald; Damasceno, Itala; Malavasi, Aldo; Goncalves, Nilmara; Costa, Maria de Lourdes; Walder, Julio; Nascimento, Antonio

    2006-01-01

    A key point of the sterile insect technique applied to the medfly, Ceratitis capitata, is that the sterile males produced in the laboratory should have at least a minimal sexual compatibility with wild females. Among several genetic sexing tsl (Temperature Sensitive Lethal) strains of C. capitata mass-reared around the world, the Biofabrica Moscamed Brasil has chosen the most recent mass produced tsl strain, Vienna 8 (V8), which has been evaluated in the San Francisco River Valley, Brazil, since April, 2005. The tests were accomplished in field cages, with different treatments for V8 males, sterile or fertile, exposed to the aroma of ginger root oil (GRO) or not, versus wild males and females. Males of one strain (V8 or wild) were painted white on the thorax the day before the mating tests. All the insects were virgin, and early in the morning (7-8 A.M.) males were released inside the field cages, 10 min. before females. Mating pairs were collected in glass vials, until early afternoon. From this raw data, both the type of male mating and the time in copula were recorded for each pair. Then, the total percentage of mated females, the RSI (Relative Sterility Index), and Fried's competitiveness values (C), were calculated for each field cage. The percentage of females mated was statistically higher to sterile males exposed to GRO than to non exposed to GRO. Time in copula was significantly higher for wild flies than for laboratory flies, except for the case of fertile V8 males exposed to GRO x wild females. The RSI and C values were significantly higher for V8 males (irradiated and fertile) treated with GRO than for V8 males not treated with GRO. The results indicate that there is adequate sexual compatibility between sterile males of the tsl Vienna 8 strain and wild C. capitata females from the San Francisco River Valley, Brazil. Also, the radiation dose of 95 Gy, used to sterilize the males, did not affect their sexual activity. Ginger root oil acted as a

  17. Sterile medfly males of the tsl Vienna 8 genetic sexing strain display improved mating performance with ginger root oil

    Energy Technology Data Exchange (ETDEWEB)

    Paranhos, Beatriz Jordao; Alves, Renata Morelli, E-mail: bjordao@cpatsa.embrapa.b [EMBRAPA Semi-Arido, Petrolina, PE (Brazil); McInnis, Donald [U.S. Department of Agriculture (USDA/ARS/PBARC), Honolulu, HI (United States). Agricultural Research Service. Pacific Basin Agricultural Research Center; Uramoto, Keiko [Universidade de Sao Paulo (USP), SP (Brazil); Damasceno, Itala; Malavasi, Aldo [Biofabrica Moscamed Brasil, Juazeiro, BA (Brazil); Goncalves, Nilmara [Valexport, Petrolina, PE (Brazil); Costa, Maria de Lourdes; Walder, Julio [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Nascimento, Antonio [EMBRAPA Mandioca e Fruticultura, Cruz das Almas, BA (Brazil)

    2006-07-01

    A key point of the sterile insect technique applied to the medfly, Ceratitis capitata, is that the sterile males produced in the laboratory should have at least a minimal sexual compatibility with wild females. Among several genetic sexing tsl (Temperature Sensitive Lethal) strains of C. capitata mass-reared around the world, the Biofabrica Moscamed Brasil has chosen the most recent mass produced tsl strain, Vienna 8 (V8), which has been evaluated in the San Francisco River Valley, Brazil, since April, 2005. The tests were accomplished in field cages, with different treatments for V8 males, sterile or fertile, exposed to the aroma of ginger root oil (GRO) or not, versus wild males and females. Males of one strain (V8 or wild) were painted white on the thorax the day before the mating tests. All the insects were virgin, and early in the morning (7-8 A.M.) males were released inside the field cages, 10 min. before females. Mating pairs were collected in glass vials, until early afternoon. From this raw data, both the type of male mating and the time in copula were recorded for each pair. Then, the total percentage of mated females, the RSI (Relative Sterility Index), and Fried's competitiveness values (C), were calculated for each field cage. The percentage of females mated was statistically higher to sterile males exposed to GRO than to non exposed to GRO. Time in copula was significantly higher for wild flies than for laboratory flies, except for the case of fertile V8 males exposed to GRO x wild females. The RSI and C values were significantly higher for V8 males (irradiated and fertile) treated with GRO than for V8 males not treated with GRO. The results indicate that there is adequate sexual compatibility between sterile males of the tsl Vienna 8 strain and wild C. capitata females from the San Francisco River Valley, Brazil. Also, the radiation dose of 95 Gy, used to sterilize the males, did not affect their sexual activity. Ginger root oil acted as a

  18. Possibilities of using radiation induced F1 sterility for control of European corn borer in Romania

    International Nuclear Information System (INIS)

    Barbulescu, A.; Rosca, I.

    1993-01-01

    Investigations were undertaken to develop the foundation for control in the future of the European corn borer, Ostrinia nubilalis (Huebner), with a pest management system based on sterility expressed to the greatest extent during the F 1 generation of progeny of moths irradiated with gamma rays. As a basis for the mass rearing of the pest, a diet was developed from locally available ingredients. The ingredients are bean meal, wheat bran, brewe's yeast, milk powder substitute for calves, salt mixture used in poultry production, sugar, ascorbic acid, sorbic acid, glacial acetic acid, formaldehyde, agar and water. Using this diet, 1000 moths can be reared for as little as one US dollar. Complete sterility induced by exposure to gamma rays occurs at a lower dose in females than in males. When males that are exposed as six-day-old pupae to 150 Gy are mated to untreated females, 67.5% of the eggs hatch. Further, when the sons of treated males are mated to untreated females, 42.8% of the eggs hatch, when daughters of treated males are mated to untreated males, 40.7% of the eggs hatch, and when sons and daughters of treated males are mated to each other, 9.1% of the eggs hatch. The amount of mortality following egg hatch was not recorded. However, in field cage experiments, F 1 larvae damaged 4, 8 and 0% of corn stalks for these respective crosses compared with the 76% damage by larvae from untreated parents. The corresponding yield of kernels of corn in grammes per plant was 57, 42, 46, and 27. In order to mark moths for filed studies they were reared on diet containing Calco red dye. Traps baited with the various enantiomers of the sex pheromone were used to study the dispersal of released moths and the dates of adult moth emergence in various regions of Romania. (author). 20 refs, 12 tabs

  19. Mediterranean Diet and Its Correlates among Adolescents in Non-Mediterranean European Countries: A Population-Based Study.

    Science.gov (United States)

    Novak, Dario; Štefan, Lovro; Prosoli, Rebeka; Emeljanovas, Arunas; Mieziene, Brigita; Milanović, Ivana; Radisavljević-Janić, Snežana

    2017-02-22

    Little is known about the factors which might influence the adherence to a Mediterranean diet in non-Mediterranean European countries. Thus, the main purpose of this study was to determine the associations between socioeconomic, psychological, and physical factors on a Mediterranean diet. In this cross-sectional study, participants were 14-18-year-old adolescents ( N = 3071) from two non-Mediterranean countries: Lithuania ( N = 1863) and Serbia ( N = 1208). The dependent variable was Mediterranean diet, and was assessed with the Mediterranean Diet Quality Index for children and adolescents questionnaire. Independent variables were gender, body-mass index, self-rated health, socioeconomic status, psychological distress, physical activity, and sedentary behavior. The associations between dependent and independent variables were analyzed by using logistic regression. Results showed that higher adherence to a Mediterranean diet was associated with higher self-rated health, socioeconomic status, and physical activity, yet low adherence to a Mediterranean diet was associated with being female, having higher body-mass index, psychological distress, and sedentary behavior. Our findings suggest that future studies need to explore associations between lifestyle habits-especially in target populations, such as primary and secondary school students.

  20. Economic evaluation of three alternative methods for control of the Mediterranean fruit fly (Diptera: Tephritidae) in Israel, Palestinian Territories, and Jordan

    International Nuclear Information System (INIS)

    Enkerlin, W.; Mumford, J.

    1997-01-01

    The Mediterranean fruit fly, Ceratitis capitata (Wiedemann), is a major pest of fruit crops in the Mediterranean Basin countries. If no control measures are applied in Israel, Palestinian Territories, and Jordan against this pest, the annual fruit losses are estimated to be about U.S. $365 million, which is more than half the total revenue produced by fruits considered to be Mediterranean fruit fly hosts in these countries. Under the current control programs, the direct damage (yield loss and control costs) and indirect damage (environmental impact and market loss) amount to U.S. $192 million per year. This amount could increase each year if the current control programs are kept. The aim of this study was to evaluate, on a regional basis, the economic returns of 3 improved alternative Mediterranean fruit fly control methods using a 9-yr time frame. The control alternatives include population suppression using bait sprays, population suppression using massive release of sterile male flies, and population eradication also using massive releases of sterile male flies. For each option, an action plan was prepared which includes intensity, frequency and timing of sampling (trapping and fruit gathering), control (bait sprays and sterile male releases), and postcontrol (quarantine and emergency capacity) techniques. For the economic evaluation costs and benefits at net present value are computed for each control option to estimate the economic indices. Results indicate that the 3 area-wide control options are technically and economically feasible and all are better than the current control programs. For each option, the economic returns on a medium and long term are discussed, along with the environmental impact. Over the 9-yr time frame, the greatest economic return is from the sterile male suppression option. Over a much longer time frame, the greatest return is for the sterile male eradication option

  1. Some biological characters of two TSL genetic sexing strains of the Mediterranean Fruit Fly Ceratitis Capitata (WIED.) for its control using Sit

    International Nuclear Information System (INIS)

    Cacers, C.; El-Kholy, E.M.S.

    2007-01-01

    A biological comparison between two t sl s trains of the Mediterranean fruit fly, Ceratitis capitata Wied., was done. The biological parameters of this comparison involved pupal production, pupal emergence, adult sex ratio and flying ability. Two kinds of larval media were used (bran or carrot powder). Survival of the produced flies was also determined when deprived from water and food. Larval rearing was done in 5 kg trays (usual mass rearing) on sugar and bran medium or in experimental Petri dishes (15 cm in diameter and 1 cm in height) on powdered carrot medium. The results obtained revealed a better performance of Vienna 8 strain (V-8) than Vienna 7 strain (V-7) when larval rearing was carried out in 5 kg trays on the usual bran medium. However, when carrot larval diet was offered in small Petri dishes, V-7 was better as compared to V-8 strain. Adult males or females produced by V-7 showed longer survival than those produced by V-8 when adults were kept without food or water

  2. A search for neutrino–antineutrino mass inequality by means of sterile neutrino oscillometry

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, M.V., E-mail: gear8mike@gmail.com [Department of Physics, University of Jyväskylä, 40014 Jyväskylä (Finland); St. Petersburg State University, 198504 Peterhof, St. Petersburg (Russian Federation); Loo, K.K. [Department of Physics, University of Jyväskylä, 40014 Jyväskylä (Finland); Novikov, Yu.N. [St. Petersburg State University, 198504 Peterhof, St. Petersburg (Russian Federation); Petersburg Nuclear Physics Institute, 188300 Gatchina, St. Petersburg (Russian Federation); Trzaska, W.H. [Department of Physics, University of Jyväskylä, 40014 Jyväskylä (Finland); Wurm, M. [Johannes Gutenberg University Mainz, 55099 Mainz (Germany)

    2015-11-15

    The investigation of the oscillation pattern induced by the sterile neutrinos might determine the oscillation parameters, and at the same time, allow to probe CPT symmetry in the leptonic sector through neutrino–antineutrino mass inequality. We propose to use a large scintillation detector like JUNO or LENA to detect electron neutrinos and electron antineutrinos from MCi electron capture or beta decay sources. Our calculations indicate that such an experiment is realistic and could be performed in parallel to the current research plans for JUNO and RENO. Requiring at least 5σ confidence level and assuming the values of the oscillation parameters indicated by the current global fit, we would be able to detect neutrino–antineutrino mass inequality of the order of 0.5% or larger, which would imply a signal of CPT anomalies.

  3. Delayed pulsar kicks from the emission of sterile neutrinos

    International Nuclear Information System (INIS)

    Kusenko, Alexander; Mandal, Bhabani Prasad; Mukherjee, Alok

    2008-01-01

    The observed velocities of pulsars suggest the possibility that sterile neutrinos with mass of several keV are emitted from a cooling neutron star. The same sterile neutrinos could constitute all or part of cosmological dark matter. The neutrino-driven kicks can exhibit delays depending on the mass and the mixing angle, which can be compared with the pulsar data. We discuss the allowed ranges of sterile neutrino parameters, consistent with the latest cosmological and x-ray bounds, which can explain the pulsar kicks for different delay times

  4. Searches for light sterile neutrinos with multitrack displaced vertices

    Science.gov (United States)

    Cottin, Giovanna; Helo, Juan Carlos; Hirsch, Martin

    2018-03-01

    We study discovery prospects for long-lived sterile neutrinos at the LHC with multitrack displaced vertices, with masses below the electroweak scale. We reinterpret current displaced vertex searches making use of publicly available, parametrized selection efficiencies for modeling the detector response to displaced vertices. We focus on the production of right-handed WR bosons and neutrinos N in a left-right symmetric model, and find poor sensitivity. After proposing a different trigger strategy (considering the prompt lepton accompanying the neutrino displaced vertex) and optimized cuts in the invariant mass and track multiplicity of the vertex, we find that the LHC with √{s }=13 TeV and 300 fb-1 is able to probe sterile neutrino masses between 10 GeV right-handed gauge boson mass of 2 TeV work joins other efforts in motivating dedicated experimental searches to target this low sterile neutrino mass region.

  5. Sterile insect technique for the management of the oriental fruit fly in Guimaras iasland

    International Nuclear Information System (INIS)

    Golez, H.; Manoto, E.

    1996-01-01

    Mango is an important fruit crop in the country as shown by increasing demand for the fruit both in local and domestic markets. In particular, the island of Guimaras is now being developed as the mango province of the country since the soil and climate are highly suitable for its growth and development. Today, there are more than 250,000 trees grown in the island and the local government plans to plant more than 1 million trees by the year 2000. The production of quality fruits is however, hampered by the presence of fruit flies. A new strategy in fruit fly control is the sterile insect technique which will be implemented in the island of Guimaras. SIT involves mass rearing, sterilization and release of sterile fruit flies in target areas to stop native flies from reproducing. Preparatory phase of the project include campaigns launched to inform growers, government officials and private sectors on the objectives and mechanics of SIT through press releases, workshops and meetings. Basic ecological studies which involved determination of host fruits, degree of fruit infestation, population dynamics and fruit fly dispersal are presented. Estimates of fruit fly population showed that more insects were present in natural vegetation as compared to mix plantation and low population was recorded in pure orchards. Preliminary results of male annihilation technique using a bait consisting of methyl eugenol and malathion placed in fiber boards also revealed that male populations were reduced to low levels, provided that wide area approach is considered. Otherwise, reinfestation of limited areas by flies will occur. Continuous monitoring of flies in the whole island is now being undertaken. Sterile insect technique was demonstrated in the small islet of Naoay, south west of the main island of Guimaras. Results of several releases showed that no unmarked flies were captured from monitoring traps, indicating that sterile flies suppressed the population of wild flies in the area

  6. Sterilization by cobalt 60 of the mediterranean fruit fly Ceratitis Capitate Wied

    International Nuclear Information System (INIS)

    Dimundu Puena, I.; Cirio, Ugo.

    1978-01-01

    Ceratitis capitata have been irradiated with 2, 4, 6 and 10 Krad of a Co-60 gamma irradiator at 300 rad/min flow. Following results have been obtained: abundant and regular egg laid at 1 to 2 krads, reduced but regular egg laid at 4 krads and total sterility from 6 krads. The 10 krads irradiated insects exhibit satisfactory life time and activity. The 6 and above krads irradiated females are completely sterile but have the laid reflex. The 8 krads irradiated males exhibit sexual strength comparable to that of normal males. Males fertility is decreased with increasing irradiation dose, eggs obtained with normal female have fertility of less than 1 % for doses above 7 krads. However it appears that at 8 krads dose, some males can form again normal spermatozoids after 20 to 30 days. The recommended irradiation dose is 10 krads

  7. Sterile Neutrino Search with MINOS

    International Nuclear Information System (INIS)

    Devan, Alena V.

    2015-01-01

    MINOS, Main Injector Neutrino Oscillation Search, is a long-baseline neutrino oscillation experiment in the NuMI muon neutrino beam at the Fermi National Accelerator Laboratory in Batavia, IL. It consists of two detectors, a near detector positioned 1 km from the source of the beam and a far detector 734 km away in Minnesota. MINOS is primarily designed to observe muon neutrino disappearance resulting from three flavor oscillations. The Standard Model of Particle Physics predicts that neutrinos oscillate between three active flavors as they propagate through space. This means that a muon-type neutrino has a certain probability to later interact as a different type of neutrino. In the standard picture, the neutrino oscillation probabilities depend only on three neutrino flavors and two mass splittings, Δm 2 . An anomaly was observed by the LSND and MiniBooNE experiments that suggests the existence of a fourth, sterile neutrino flavor that does not interact through any of the known Standard Model interactions. Oscillations into a theoretical sterile flavor may be observed by a deficit in neutral current interactions in the MINOS detectors. A distortion in the charged current energy spectrum might also be visible if oscillations into the sterile flavor are driven by a large mass-squared difference, Δm s 2 ~ 1 eV 2 . The results of the 2013 sterile neutrino search are presented here.

  8. Evaluation of Lepidoptera population suppression by radiation induced sterility. Proceedings of a final research co-ordination meeting

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-04-01

    This publication results from the second FAO/IAEA Research Co-ordination Project (CRP) on Inherited Sterility in Lepidoptera (caterpillars of moths). The present CRP and a previous one entitled 'Radiation Induced F{sub 1} Sterility in Lepidoptera for Area-Wide Control' were initiated in response to requests from Member States for the development of environment friendly alternatives to current control of moth pests. The first five-year CRP (1987-1991) dealt primarily with aspects such as determining the effects of various radiation dose levels on the resulting sterility in the treated parents and their F{sub 1} progeny in different Lepidoptera species. In addition, models were developed on the suppressive effects of F{sub 1} sterility on field populations, and some studies were conducted in laboratory or field cages to assess the impact of inherited sterility on pest suppression. The research results were published in 1993 in the IAEA Panel Proceedings Series. This follow-up CRP (1994-1998) has built on the results of the first CRP and has focused on addressing a more challenging phase, consisting of rearing key pest moths and evaluating their application for pest control purposes. The specific objective of the CRP was therefore to assess the potential of suppressing populations of caterpillar pests in the field by inherited sterility methods, i.e. by rearing and releasing irradiated moths and/or their progeny in combination with other biological control methods. The ultimate goal is to have alternative environment-friendly control methods available to be able to reduce the vast quantities of insecticide that are used in agriculture to combat Lepidoptera pests and that adversely affect the trade balance of developing countries because they must use hard currency to import them. The two FAO/IAEA sponsored Lepidoptera CRPs have resulted in expanded research and implementation programmes on F{sub 1} sterility in combination with natural enemies. Such programmes are

  9. Evaluation of Lepidoptera population suppression by radiation induced sterility. Proceedings of a final research co-ordination meeting

    International Nuclear Information System (INIS)

    2002-04-01

    This publication results from the second FAO/IAEA Research Co-ordination Project (CRP) on Inherited Sterility in Lepidoptera (caterpillars of moths). The present CRP and a previous one entitled 'Radiation Induced F 1 Sterility in Lepidoptera for Area-Wide Control' were initiated in response to requests from Member States for the development of environment friendly alternatives to current control of moth pests. The first five-year CRP (1987-1991) dealt primarily with aspects such as determining the effects of various radiation dose levels on the resulting sterility in the treated parents and their F 1 progeny in different Lepidoptera species. In addition, models were developed on the suppressive effects of F 1 sterility on field populations, and some studies were conducted in laboratory or field cages to assess the impact of inherited sterility on pest suppression. The research results were published in 1993 in the IAEA Panel Proceedings Series. This follow-up CRP (1994-1998) has built on the results of the first CRP and has focused on addressing a more challenging phase, consisting of rearing key pest moths and evaluating their application for pest control purposes. The specific objective of the CRP was therefore to assess the potential of suppressing populations of caterpillar pests in the field by inherited sterility methods, i.e. by rearing and releasing irradiated moths and/or their progeny in combination with other biological control methods. The ultimate goal is to have alternative environment-friendly control methods available to be able to reduce the vast quantities of insecticide that are used in agriculture to combat Lepidoptera pests and that adversely affect the trade balance of developing countries because they must use hard currency to import them. The two FAO/IAEA sponsored Lepidoptera CRPs have resulted in expanded research and implementation programmes on F 1 sterility in combination with natural enemies. Such programmes are under way in Tunisia

  10. Sterile neutrino search with the Double Chooz experiment

    Energy Technology Data Exchange (ETDEWEB)

    Hellwig, Denise; Bekman, Ilja; Kampmann, Philipp; Schoppmann, Stefan; Soiron, Michael; Stahl, Achim; Wiebusch, Christopher [III. Physikalisches Institut B, RWTH Aachen (Germany)

    2016-07-01

    The Double Chooz experiment is a reactor neutrino disappearance experiment located at the Chooz nuclear power plant, France. It measures the electron-antineutrino flux of the two nuclear reactors with two detectors of identical design. A far detector at a distance of about 1 km is operating since 2011; a near detector at a distance of about 400 m is operating since the end of 2014. The combination of the two detectors offers sensitivity to sterile neutrino mixing parameters. Sterile neutrinos are neutrino mass states not taking part in weak interactions, but may mix with known neutrino states. This induces additional mixing angles and mass differences. This talk describes the search for sterile neutrinos and the sensitivity of Double Chooz to the mixing angle θ{sub 14}.

  11. Suppression of oriental fruit moth (Grapholita molesta, Lepidoptera: Tortricidae) populations using the sterile insect technique

    International Nuclear Information System (INIS)

    Genchev, N.

    2002-01-01

    The Oriental fruit moth (OFM) is a major insect pest of peaches in Bulgaria. Its control usually requires several insecticide treatments per season. This, however, gives rise to serious toxic residue problems. A program for suppression of OFM populations involving the use of sterile-insect technique (SIT) has been developed as an alternative to the chemical methods for OFM. Relevant information regarding laboratory rearing, radiation and basic biology are presented here. Expected effects of some release programs are modelled using appropriate mathematical simulations. Results obtained in a small field experiment showed high efficacy of a program integrating F 1 male sterility technique and classic SIT. (author)

  12. Electrophoretic multilocus analysis for the study of natural populations of the Mediterranean fruit fly, Ceratitis capitata (Wied.)

    International Nuclear Information System (INIS)

    Gasperi, G.; Malacrida, A.R.; Milani, R.; Guglielmino, C.R.

    1990-01-01

    Data concerning spatial and/or temporal variation among 29 samples of four populations of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann) were obtained by computation of gene frequency values at 25 biochemical loci. The four populations came from Africa (Kenya and Reunion) and from the Mediterranean basin (Sardinia and Procida Island). Statistical parameters of genetic variation included average heterozygosity per locus, proportion of polymorphic loci and average number of alleles per locus. The data were analysed using Principal Component Analysis and Wright's fixation index. Significant differences in genetic heterogeneity were observed on a regional scale in relation to the dispersion of the fly from its supposed area of origin (East Africa) towards the periphery (Mediterranean region). The samples from Procida, collected at different seasons for four consecutive years (1983-1986), provided consistent indications of temporal changes in the genetic structure of this population, and permitted evaluation of the efficiency of a sterilized male strain (T-101) released during a sterile insect technique programme on Procida in 1986. (author). 9 refs, 1 fig., 1 tab

  13. Radiation sterilization facility for melon fly

    International Nuclear Information System (INIS)

    Danno, A.

    1985-01-01

    The melon fly (Dacus cucurbitae Coquillett) has been observed in Amami Island since l975. Kagoshima Prefecture has had a melon fly eradication project underway since 1979. A mass-fearing facility and a radiation sterilization facility were constructed in Naze in March of l98l. In the early stages of the project, sterile insects were produced at the rate of 4 x l0/sup 6/ pupae/week. In the later stages, the activity of the project was enlarged by tenfold. The conditions for design of the radiation sterilization facility, which has been developed with a central control system for automated irradiation, are examined from an engineering standpoint

  14. Implication of sterile fermions in particle physics and cosmology

    International Nuclear Information System (INIS)

    Lucente, M.

    2015-01-01

    The Ph.D. thesis work summarised in this manuscript was dedicated to studying several aspects of the phenomenology of Standard Model (SM) extensions by sterile fermions, in particular their impact for particle and astro-particle physics. An important part of the work is dedicated to a class of SM extensions which allow to explain the smallness of the observed neutrino masses (as well as their mixings) by linking them to the breaking of total lepton number, in the framework of the so-called Inverse seesaw mechanism (ISS). The work described in the thesis addresses the role of these sterile states in providing a satisfactory explanation to 3 open observational problems of the SM: the generation of neutrino masses and mixings, a viable dark matter candidate, and the dynamical generation of the baryon asymmetry of the Universe. We identified the minimal ISS realisation accounting for the observed neutrino data while at the same time complying with all available experimental and observational constraints. This study was based on a perturbative approach to the diagonalization of the neutrino mass matrix, which allowed to identify the number of states associated with the different mass scales. Our study revealed that, depending on the number of additional sterile fermion fields, the ISS can accommodate both a 3-flavour mixing scheme and a 3+more mixing scheme. The potential role of these sterile states as dark matter (DM) candidates led us to carry a dedicated study of the viability of the sterile fermion dark matter hypothesis in a minimal ISS realisation (in which the SM is extended by 2 right-handed neutrinos and 3 additional sterile fermion fields). The degeneracy in the sterile neutrino mass spectrum - which is characteristic of low scale seesaw models with approximate lepton number conservation - can play a relevant role in cosmology, since it allows us to explain the observed baryon asymmetry of the Universe via lepto-genesis. We identified different lepton number

  15. Testing sterile neutrino extensions of the Standard Model at future lepton colliders

    Science.gov (United States)

    Antusch, Stefan; Fischer, Oliver

    2015-05-01

    Extending the Standard Model (SM) with sterile ("right-handed") neutrinos is one of the best motivated ways to account for the observed neutrino masses. We discuss the expected sensitivity of future lepton collider experiments for probing such extensions. An interesting testable scenario is given by "symmetry protected seesaw models", which theoretically allow for sterile neutrino masses around the electroweak scale with up to order one mixings with the light (SM) neutrinos. In addition to indirect tests, e.g. via electroweak precision observables, sterile neutrinos with masses around the electroweak scale can also be probed by direct searches, e.g. via sterile neutrino decays at the Z pole, deviations from the SM cross section for four lepton final states at and beyond the WW threshold and via Higgs boson decays. We study the present bounds on sterile neutrino properties from LEP and LHC as well as the expected sensitivities of possible future lepton colliders such as ILC, CEPC and FCC-ee (TLEP).

  16. Changes in total lipids and fatty acid contents in sterilized flies of the onion bulb fly, Eumerus Amoenus loew (Diptera; Syrphidae)

    International Nuclear Information System (INIS)

    Souka, S.; Hegazy, R.A.; El-Saeadi, A.A.; Abdel-Salam, A.L.

    1996-01-01

    The changes in total lipids and fatty acid composition of the 5 day-old adults sterilized as 5,6 and 7 day-old pupae, reared on onion, were determined. Females of E. Amoenus adults contained significantly higher (1.8 folds) total lipid than males. Percent reduction in lipid contents increased by sterilization. The relative abundance of the fatty acids C 16, C 18:1, C 18:2 and C 14 was similar in both sexes. The content of total saturated fatty acid decreased in males sterilized as pupae 5 and 6 day-old, however, different data were observed for those irradiated as 7 day-old pupae. 1 fig., 1 tab

  17. Searching for Sterile Neutrinos with MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Timmons, Ashley [Manchester U.

    2016-01-01

    This document presents the latest results for a 3+1 sterile neutrino search using the $10.56 \\times 10^{20}$ protons-on-target data set taken from 2005 - 2012. By searching for oscillations driven by a large mass splitting, MINOS is sensitive to the existence of sterile neutrinos through any energy dependent deviations using a charged current sample, as well as looking at any relative deficit between neutral current events between the far and near detectors. This document will discuss the novel analysis that enabled a search for sterile neutrinos setting a limit in the previously unexplored regions in the parameter space $\\{\\Delta m^{2}_{41}, \\sin^2\\theta_{24}\\}$. The results presented can be compared to the parameter space suggested by LSND and MiniBooNE and complements other previous experimental searches for sterile neutrinos in the electron neutrino appearance channel.

  18. MR imaging of ''sterilized'' lymphoma

    International Nuclear Information System (INIS)

    Zerhouni, E.A.; Fishman, E.K.; Jones, R.; Siegelman, S.S.; Soulen, R.L.

    1986-01-01

    Residual masses are commonly observed after effective therapy in patients with lymphoma. These masses may be sterile but their presence poses a management problem, inasmuch as there is no adequate means of distinguishing sterile from active masses. The potential role of MR imaging in this context was evaluated by studying a group of 15 patients with stable, residual, presumably inactive masses (as determined from CT) and comparing the MR imaging findings in patients with newly diagnosed, untreated or recently treated lymphoma. All patients underwent an MR imaging examination consisting of one short repetition time (TR), short echo time (TE) (T1-weighted) sequence and one long TR, long TE(T2-weighted) sequence. The signal intensity of the masses was compared with that of fat in each patient, for each sequence. In selected patients, sequential examinations showed a progressive evolution toward the inactive pattern over a period of several weeks. Active and inactive disease are well depicted on T1-weighted sequences but are not distinguishable from each other. On T2-weighted sequences active disease is poorly demonstrated because the lesions are isointense with fat, whereas inactive masses remain clearly identifiable because they are of much lower signal intensity than fat

  19. Dark matter relic abundance and light sterile neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Yi-Lei [Center for High Energy Physics,Peking University, Beijing 100871 (China); Zhu, Shou-hua [Center for High Energy Physics,Peking University, Beijing 100871 (China); Institute of Theoretical Physics & State Key Laboratory of Nuclear Physics and Technology,Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter,Beijing 100871 (China)

    2017-01-09

    In this paper, we calculate the relic abundance of the dark matter particles when they can annihilate into sterile neutrinos with the mass ≲100 GeV in a simple model. Unlike the usual standard calculations, the sterile neutrino may fall out of the thermal equilibrium with the thermal bath before the dark matter freezes out. In such a case, if the Yukawa coupling y{sub N} between the Higgs and the sterile neutrino is small, this process gives rise to a larger Ω{sub DM}h{sup 2} so we need a larger coupling between the dark matter and the sterile neutrino for a correct relic abundance.

  20. 7 keV sterile neutrino dark matter from split flavor mechanism

    International Nuclear Information System (INIS)

    Ishida, Hiroyuki; Takahashi, Fuminobu; Tokyo Univ., Kashiwa

    2014-02-01

    The recently discovered X-ray line at about 3.5 keV can be explained by sterile neutrino dark matter with mass, m s ≅ 7 keV, and the mixing, sin 2 2θ∝10 -10 . Such sterile neutrino is more long-lived than estimated based on the seesaw formula, which strongly suggests an extra flavor structure in the seesaw sector. We show that one can explain both the small mass and the longevity based on the split flavor mechanism where the breaking of flavor symmetry is tied to the breaking of the B-L symmetry. In a supersymmetric case we find that the 7 keV sterile neutrino implies the gravitino mass about 100 TeV.

  1. Sterile Neutrino Search with MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Devan, Alena V. [College of William and Mary, Williamsburg, VA (United States)

    2015-08-01

    MINOS, Main Injector Neutrino Oscillation Search, is a long-baseline neutrino oscillation experiment in the NuMI muon neutrino beam at the Fermi National Accelerator Laboratory in Batavia, IL. It consists of two detectors, a near detector positioned 1 km from the source of the beam and a far detector 734 km away in Minnesota. MINOS is primarily designed to observe muon neutrino disappearance resulting from three flavor oscillations. The Standard Model of Particle Physics predicts that neutrinos oscillate between three active flavors as they propagate through space. This means that a muon-type neutrino has a certain probability to later interact as a different type of neutrino. In the standard picture, the neutrino oscillation probabilities depend only on three neutrino flavors and two mass splittings, Δm2. An anomaly was observed by the LSND and MiniBooNE experiments that suggests the existence of a fourth, sterile neutrino flavor that does not interact through any of the known Standard Model interactions. Oscillations into a theoretical sterile flavor may be observed by a deficit in neutral current interactions in the MINOS detectors. A distortion in the charged current energy spectrum might also be visible if oscillations into the sterile flavor are driven by a large mass-squared difference, ms2 ~ 1 eV2. The results of the 2013 sterile neutrino search are presented here.

  2. Capabilities of long-baseline experiments in the presence of a sterile neutrino

    International Nuclear Information System (INIS)

    Dutta, Debajyoti; Gandhi, Raj; Kayser, Boris; Masud, Mehedi; Prakash, Suprabh

    2016-01-01

    Assuming that there is a sterile neutrino, we ask what then is the ability of long-baseline experiments to i) establish that neutrino oscillation violates CP, ii) determine the three-neutrino mass ordering, and iii) determine which CP-violating phase or phases are the cause of any CP violation that may be observed. We find that the ability to establish CP violation and to determine the mass ordering could be very substantial. However, the effects of the sterile neutrino could be quite large, and it might prove very difficult to determine which phase is responsible for an observed CP violation. We explain why a sterile neutrino changes the long-baseline sensitivities to CP violation and to the mass ordering in the ways that it does. We note that long-baseline experiments can probe the presence of sterile neutrinos in a way that is different from, and complementary to, the probes of short-baseline experiments. We explore the question of how large sterile-active mixing angles need to be before long-baseline experiments can detect their effects, or how small they need to be before the interpretation of these experiments can safely disregard the possible existence of sterile neutrinos.

  3. Recent advances in the rearing of Glossina pallidipes Austen

    International Nuclear Information System (INIS)

    Leegwater-Van der Linden, M.E.

    1980-01-01

    The rearing technique of Glossina pallidipes Austen in Amsterdam is described. The flies are kept at 25 0 C, 80% relative humidity in very dim light which operates 12 hours a day. Flies are fed on ears of lop-eared rabbits inside the colony room. Nine-day-old females are massmated with an equal number of 12-day-old males for approximately three days. Mated females are kept without males. Under these circumstances the interlarval period is nine years. The first larva is deposited on the 20th day after emergence and the mean longevity hereafter is 60 days average or 101 days with individual attention. Productivity has been observed from 1977 onward. The insemination rate gradually increased from 66 to 97%, and fecundity from about 0.5 to 0.8. Premating deaths remained at a level of 4%. The eclosion rate was 92% and pupal weight 39 mg. In the Amsterdam practice these figures imply that nearly one third of the weekly pupal production is needed to maintain the colony at a set number. The remainder can be used for other purposes. Judging from observations and experience it seems that prevention of chemical contamination and any disturbance, mass-mating at the appropriate time and a very high humidity are relevant points in the various techniques used in rearing G. pallidipes. Attention is now being given to the viability of the colony in Amsterdam for eradicating G. pallidipes in East Africa. Females emerging from pupae sent from a test area near Tanga, Tanzania, were readily inseminated by males from the Amsterdam colony, indicating the possibility of using the sterile male technique for reduction of G. pallidipes in East Africa. (author)

  4. Mediterranean fruit fly female attractant studies in support of the sterile insect technique: trapping experiments conducted on the island of Chios, Greece

    International Nuclear Information System (INIS)

    Katsoyannos, B.I.; Papadopoulos, N.T.; Kouloussis, N.A.

    1999-01-01

    This paper contains information on a four-year research programme co-ordinated by the International Atomic Energy Agency. The main objective of the programme was to develop a trapping system for females of the Mediterranean fruit fly (medfly), Ceratitis capitata (Diptera: Tephritidae), for practical use in Sterile Insect Technique (SIT) programs and to design and evaluate a trap to obtain eggs from wild female medflies in order to estimate sterility induction in the field population. The experiments were conducted from July to September 1994-1997 on the island of Chios, Greece, in citrus orchards with low to medium medfly populations. Different trap types and several trap treatments consisting of sex and food based attractants were tested, following a standard coordinated experimental protocol. The most extensively tested were three food based 'female' attractants (FA-3), namely ammonium acetate (AA), 1,4 diaminobutane (putrescine) and trimethylamine, all formulated in dispensers lasting one month. These attractants were evaluated in combinations of two (AA + putrescine, termed FA-2) or three (FA-3) dispensers in various traps, including dry (provided with DDVP) or wet (provided with water and 0.01% surfactant) plastic International Pheromone's McPhail traps (IPMT). Among the various traps and treatments tested, the most effective for medfly capture was the wet IPMT, baited with FA-3 attractants. This treatment captured predominantly females and was relatively selective for medflies. In dry IPMT traps, the FA-3 were as effective as the standard 300 ml aqueous solution of 9% of the protein NuLure and 3% borax, but much more medfly selective. Dry IPMT traps were also more selective than wet ones. FA-3 baited wet Tephri traps (a Spanish modification of the McPhail trap), performed somewhat poorer than IPMT traps. Other dry trap types tested were not effective. Additional experiments showed that certain insecticide formulations used in dry traps may have a repellent

  5. Investigation on mating habit and sexual competition ability of Helicoverpa armigera sterilized by irradiation

    International Nuclear Information System (INIS)

    Xia Darong; Yang Rongxin; Gu Weiping; Zhang Yanjun

    1999-01-01

    Mating habit and sexual competition ability of Helicoverpa armigera irradiated with 300 Gy of γ-rays were observed. The results showed that when reared in laboratory, most adults mated at 4-7 o'clock, a small proportion of adults mated at 2-3 o'clock or at 8-9 o'clock in the morning, meanwhile wild population mated two and a half hours earlier than laboratory populations did. No difference in mating habit and sexual competition ability was found between the irradiation-sterilized and normal adults except that the effective mating rate of the former was 61.6%, one third less than that of the latter ones. Most irradiation-sterilized adults mated one time in their whole lives, only a few could mate 2-3 times and even 5 times, indicating that the multi-mating characteristic of Helicoverpa armigera was not changed by irradiation. It can be concluded that irradiated sterile insect technique is feasible for integrated controlling the cotton bollworm

  6. Captive rearing technologies and survival of pheasants (Phasianus colchicus L. after release

    Directory of Open Access Journals (Sweden)

    Marco Bagliacca

    2012-04-01

    Full Text Available Studies have repeatedly emphasized the limited survival of pheasants reared using traditional methods compared to the wild one. For this reason we performed a field trial to compare survival rates, home ranges and habitat uses of pheasants artificial hatched and reared (traditional method with pheasants artificial hatched and reared by fostering mothers (hens. A total of 117 artificially hatched pheasants, 57 artificially brooded after hatch and 60 brooded by fostering hens, were equipped with a radio necklace tag or a poncho tag. Both groups were localized two-three times a week after their release in the wild. The survival rates of the brooded-by-hen pheasants showed an improvement of survival rates, either poncho or radio tagged (Pvs 57.1% and 35.0% vs 21.1%, respectively. The average maximum dispersion was 390 and 426 m and the home range were 12.0 and 11.6 ha in artificially brooded and brooded-by-hen pheasants, respectively. The land use showed that the woods were less represented than the available in the home range of every pheasant. For this reason the woods can be reduced in the agricultural areas interspersed with natural Mediterranean vegetation.

  7. Cryopreservation of Embryos of the Mediterranean Fruit Fly Ceratitis capitata Vienna 8 Genetic Sexing Strain.

    Directory of Open Access Journals (Sweden)

    Antonios A Augustinos

    Full Text Available The Mediterranean fruit fly, Ceratitis capitata, is one of the most serious pests of fruit crops world-wide. During the last decades, area-wide pest management (AW-IPM approaches with a sterile insect technique (SIT component have been used to control populations of this pest in an effective and environment-friendly manner. The development of genetic sexing strains (GSS, such as the Vienna 8 strain, has been played a major role in increasing the efficacy and reducing the cost of SIT programs. However, mass rearing, extensive inbreeding, possible bottleneck phenomena and hitch-hiking effects might pose major risks for deterioration and loss of important genetic characteristics of domesticated insect. In the present study, we present a modified procedure to cryopreserve the embryos of the medfly Vienna 8 GSS based on vitrification and used this strain as insect model to assess the impact of the cryopreservation process on the genetic structure of the cryopreserved insects. Forty-eight hours old embryos, incubated at 24°C, were found to be the most suitable developmental stage for cryopreservation treatment for high production of acceptable hatch rate (38%. Our data suggest the absence of any negative impact of the cryopreservation process on egg hatch rate, pupation rates, adult emergence rates and stability of the temperature sensitive lethal (tsl character on two established cryopreserved lines (flies emerged from cryopreserved embryos, named V8-118 and V8-228. Taken together, our study provides an optimized procedure to cryopreserve the medfly Vienna 8 GSS and documents the absence of any negative impact on the genetic structure and quality of the strain. Benefits and sceneries for utilization of this technology to support operational SIT projects are discussed in this paper.

  8. Cryopreservation of Embryos of the Mediterranean Fruit Fly Ceratitis capitata Vienna 8 Genetic Sexing Strain.

    Science.gov (United States)

    Augustinos, Antonios A; Rajamohan, Arun; Kyritsis, Georgios A; Zacharopoulou, Antigone; Haq, Ihsan Ul; Targovska, Asya; Caceres, Carlos; Bourtzis, Kostas; Abd-Alla, Adly M M

    2016-01-01

    The Mediterranean fruit fly, Ceratitis capitata, is one of the most serious pests of fruit crops world-wide. During the last decades, area-wide pest management (AW-IPM) approaches with a sterile insect technique (SIT) component have been used to control populations of this pest in an effective and environment-friendly manner. The development of genetic sexing strains (GSS), such as the Vienna 8 strain, has been played a major role in increasing the efficacy and reducing the cost of SIT programs. However, mass rearing, extensive inbreeding, possible bottleneck phenomena and hitch-hiking effects might pose major risks for deterioration and loss of important genetic characteristics of domesticated insect. In the present study, we present a modified procedure to cryopreserve the embryos of the medfly Vienna 8 GSS based on vitrification and used this strain as insect model to assess the impact of the cryopreservation process on the genetic structure of the cryopreserved insects. Forty-eight hours old embryos, incubated at 24°C, were found to be the most suitable developmental stage for cryopreservation treatment for high production of acceptable hatch rate (38%). Our data suggest the absence of any negative impact of the cryopreservation process on egg hatch rate, pupation rates, adult emergence rates and stability of the temperature sensitive lethal (tsl) character on two established cryopreserved lines (flies emerged from cryopreserved embryos), named V8-118 and V8-228. Taken together, our study provides an optimized procedure to cryopreserve the medfly Vienna 8 GSS and documents the absence of any negative impact on the genetic structure and quality of the strain. Benefits and sceneries for utilization of this technology to support operational SIT projects are discussed in this paper.

  9. 7 keV sterile neutrino dark matter from split flavor mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, Hiroyuki [Tohoku Univ., Sendai (Japan). Dept. of Physics; Jeong, Kwang Sik [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Takahashi, Fuminobu [Tohoku Univ., Sendai (Japan). Dept. of Physics; Tokyo Univ., Kashiwa (Japan). Kavli IPMU, TODIAS

    2014-02-15

    The recently discovered X-ray line at about 3.5 keV can be explained by sterile neutrino dark matter with mass, m{sub s}≅ 7 keV, and the mixing, sin{sup 2}2θ∝10{sup -10}. Such sterile neutrino is more long-lived than estimated based on the seesaw formula, which strongly suggests an extra flavor structure in the seesaw sector. We show that one can explain both the small mass and the longevity based on the split flavor mechanism where the breaking of flavor symmetry is tied to the breaking of the B-L symmetry. In a supersymmetric case we find that the 7 keV sterile neutrino implies the gravitino mass about 100 TeV.

  10. Breakfast of champions or kiss of death? Survival and sexual performance of protein-fed, sterile Mediterranean fruit flies (Diptera: Tephritidae)

    Energy Technology Data Exchange (ETDEWEB)

    Yuval, B; Maor, M; Levy, K [Dept. of Entomology, Hebrew University, PO 12, Rehovot, 76100 (Israel); Kaspi, R [Dept. of Entomology, University of California, Davis CA 95616 (United States); Taylor, P [Dept. of Psychology, Macquarie University, NSW 2109 (Australia); Shelly, T [USDA-APHIS, 41-650 Ahiki Street, Waimanalo, HI 96795 (United States)

    2007-03-15

    The sterile insect technique (SIT) is increasingly being used around the world to control Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), the Mediterranean fruit fly as part of an area-wide integrated approach. One option that may improve the effectiveness of the SIT, by increasing the sexual competitiveness of released sterile males, consists of feeding males protein during the post-teneral stage, a diet that increases sexual performance of wild males. We examine the effects of diet on the successive hurdles males must overcome in order to inseminate females, i.e., joining leks, copulating females, having their sperm stored and inhibition of female remating. In addition, we address the effects of diet on post-release foraging success, longevity, and the ability to withstand starvation. While protein feeding universally increases the sexual success of wild males, its effect on sterile males varies with strain, experimental settings, and environmental conditions. In some cases, treatments that resulted in the best sexual performance were significantly associated with increased vulnerability to starvation. However, no particular diet affected the ability of sterile males to find nutrients in the field when these where available. We suggest it may be better to release relatively short-lived flies that are highly competitive, rather than long-lived, sexually ineffective ones. (author) [Spanish] El uso de la tecnica de insecto esteril (TIE) esta aumentando alrededor del mundo para el control de Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), la mosca mediterranea de la fruta como parte de un enfoque integrado por toda el area. Una opcion que puede mejorar la eficiencia de TIE, por medio del aumento de la capacidad de los machos esteriles liberados para competir, consiste en la alimentacion de los machos con proteina durante la etapa de pos-teneral, una dieta que aumenta el desempeno sexual de los machos naturales. Nosotros examinamos los efectos de la

  11. Postpartum Sterilization

    Science.gov (United States)

    f AQ FREQUENTLY ASKED QUESTIONS FAQ052 CONTRACEPTION Postpartum Sterilization • What is sterilization? • What is postpartum sterilization? • How is postpartum sterilization performed? • What kind of anesthesia is used for postpartum sterilization? • How ...

  12. Selected factors affecting the quality of Mediterranean fruit fly used in sterile release programs

    International Nuclear Information System (INIS)

    Serghiou, C.S.

    1977-01-01

    Adult irradiation of ceratitis capitata (Wiedemann) males resulted in a lower degree of sterility and a higher degree of competitiveness compared to pupal irradiation. It was consistently observed with both adult and pupal irradiation that the increased level of sterility obtained with increasing dose was counteracted to the same extent by decreasing level of male competitiveness. In a test in which the marking efficiency and persistence of fluorescent powders was tested, best results were obtained with Tinopal-SFG. Marking did not have any adverse effect either on male competitiveness or on fly survival. Competitiveness of irradiated male flies decreased as their exposure to chilling increased. Chilling, however, did not have any adverse effect on fly survival

  13. Scanning electron microscopy (Sem) of wings and mouth parts of the Mediterranean Fruit Fly, Ceratitis Capitata (Wield.), as influenced by the sterilizing dose of the gamma radiation

    International Nuclear Information System (INIS)

    El-akhader, E.A.H.

    2005-01-01

    In view of the fact that, any undesirable effects of gamma irradiation with the sterilizing dose (90 Gy) on wings and mouth parts of the Mediterranean fruit fly, Ceratitis Capitata (Wied.), and their associated sensilla will lead indirectly to failure of irradiated males to disperse strongly, to seek out appropriate niches or to behave synchrony with wild males or to success in the courtship with females and/or to mate. Moreover, the fly may fail to suck the plant juice. Using the scanning electron microscopy, this study was investigated. The changes which occurred to the wings and mouth parts of the med fly may be due to the sterilizing dose. One pair of wings was found to have similar typical structures in both sexes differing non-significantly in their measurements. Three different types of located sensilla were observed on each wing namely; trichoid (type sharp and blunt tipped), chaetica (type 1, 2 and 3) and basiconica (type non-socket, socket and papillae). The distribution and measurements of these sensilla were described in the text. The study of the mouth parts of both sexes recorded that there was similar pattern except significant increase between the length of the proboscis of male and female. Four different types of located sensilla were found on the mouth parts of the med fly and their measurements were given in the text. Namely trichoid (type sharp), squameformia (type 1 and socket), chaetica (type 1) and basiconica (type non-socket) were observed. The distal region of the labium was very smooth and did not bear any kind of sensilla. Pupal irradiation with the sterilizing dose resulted in different malformations in both irradiated male and female adult wings and mouth parts and their associated sensilla. Some malformations were observed in the intraveins of the irradiated male wing and in the pseudo tracheae of irradiated female labella

  14. Dark radiation sterile neutrino candidates after Planck data

    Energy Technology Data Exchange (ETDEWEB)

    Valentino, Eleonora Di; Melchiorri, Alessandro [Physics Department and INFN, Università di Roma ' ' La Sapienza' ' , Ple Aldo Moro 2, 00185, Rome (Italy); Mena, Olga, E-mail: eleonora.divalentino@roma1.infn.it, E-mail: alessandro.melchiorri@roma1.infn.it, E-mail: omena@ific.uv.es [IFIC, Universidad de Valencia-CSIC, 46071, Valencia (Spain)

    2013-11-01

    Recent Cosmic Microwave Background (CMB) results from the Planck satellite, combined with previous CMB data and Hubble constant measurements from the Hubble Space Telescope, provide a constraint on the effective number of relativistic degrees of freedom 3.62{sup +0.50}{sub −0.48} at 95% CL. New Planck data provide a unique opportunity to place limits on models containing relativistic species at the decoupling epoch. We present here the bounds on sterile neutrino models combining Planck data with galaxy clustering information. Assuming N{sub eff} active plus sterile massive neutrino species, in the case of a Planck+WP+HighL+HST analysis we find m{sub ν,} {sub sterile}{sup eff} < 0.36 eV and 3.14 < N{sub eff} < 4.15 at 95% CL, while using Planck+WP+HighL data in combination with the full shape of the galaxy power spectrum from the Baryon Oscillation Spectroscopic Survey BOSS Data Relase 9 measurements, we find that 3.30 < N{sub eff} < 4.43 and m{sub ν,} {sub sterile}{sup eff} < 0.33 eV both at 95% CL with the three active neutrinos having the minimum mass allowed in the normal hierarchy scheme, i.e. ∑m{sub ν} ∼ 0.06 eV. These values compromise the viability of the (3+2) massive sterile neutrino models for the parameter region indicated by global fits of neutrino oscillation data. Within the (3+1) massive sterile neutrino scenario, we find m{sub ν,} {sub sterile}{sup eff} < 0.34 eV at 95% CL. While the existence of one extra sterile massive neutrino state is compatible with current oscillation data, the values for the sterile neutrino mass preferred by oscillation analyses are significantly higher than the current cosmological bound. We review as well the bounds on extended dark sectors with additional light species based on the latest Planck CMB observations.

  15. Production of heavy sterile neutrinos from vector boson decay at electroweak temperatures

    Science.gov (United States)

    Lello, Louis; Boyanovsky, Daniel; Pisarski, Robert D.

    2017-02-01

    In the standard model extended with a seesaw mass matrix, we study the production of sterile neutrinos from the decay of vector bosons at temperatures near the masses of the electroweak bosons. We derive a general quantum kinetic equation for the production of sterile neutrinos and their effective mixing angles, which is applicable over a wide range of temperature, to all orders in interactions of the standard model and to leading order in a small mixing angle for the neutrinos. We emphasize the relation between the production rate and Landau damping at one-loop order and show that production rates and effective mixing angles depend sensitively upon the neutrino's helicity. Sterile neutrinos with positive helicity interact more weakly with the medium than those with negative helicity, and their effective mixing angle is not modified significantly. Negative helicity states couple more strongly to the vector bosons, but their mixing angle is strongly suppressed by the medium. Consequently, if the mass of the sterile neutrino is ≲8.35 MeV , there are fewer states with negative helicity produced than those with positive helicity. There is an Mikheyev-Smirnov-Wolfenstein-type resonance in the absence of lepton asymmetry, but due to screening by the damping rate, the production rate is not enhanced. Sterile neutrinos with negative helicity freeze out at Tf-≃5 GeV , whereas positive helicity neutrinos freeze out at Tf+≃8 GeV , with both distributions far from thermal. As the temperature decreases, due to competition between a decreasing production rate and an increasing mixing angle, the distribution function for states with negative helicity is broader in momentum and hotter than that for those with positive helicity. Sterile neutrinos produced via vector boson decay do not satisfy the abundance, lifetime, and cosmological constraints to be the sole dark matter component in the Universe. Massive sterile neutrinos produced via vector boson decay might solve the 7Li

  16. Testosterone as a Bio marker for Rapid Detection of Male Sterility of the Mediterranean Fruit Fly, Ceratitis Capitata (Wied.)

    International Nuclear Information System (INIS)

    Shoman, A.A.; El-Arab, A.E.; Aly, M.S.A.

    2000-01-01

    A rapid biochemical method for the determination of the sterility in males of the fruit fly, Ceratitis Capitata (Wied.) was established utilizing testosterone as a bio marker. Pupae (2 days before emergence) were irradiated at 90 Gy using a 60 Co-gamma-cell, unit. Testosterone level, measured by radioimmunoassay (RIA), in addition to sterility in irradiated male flies were compared to their corresponding values of the untreated control group. The data obtained revealed a highly significant decrease in the testosterone level associated with a highly significant decrease in sterility. The decrease in the hormone level was recognized during the different time intervals (24-120 hours after adult emergence). This bio marker (Testosterone) could be adopted as a rapid monitor for measurements of medfly male sterility before release in the field in a sterile insect technique (SIT) program

  17. Hysteroscopic Sterilization

    Science.gov (United States)

    ... sterilization? Sterilization is a permanent form of birth control. What is tubal sterilization? Sterilization procedures for women are ... is quicker than from other types of sterilization. What are the risks of ... on for birth control. • There is a risk of injury to the ...

  18. Mating competitiveness of Aedes albopictus radio-sterilized males in large enclosures exposed to natural conditions.

    Science.gov (United States)

    Bellini, R; Balestrino, F; Medici, A; Gentile, G; Veronesi, R; Carrieri, M

    2013-01-01

    Mating competitiveness trials have been conducted in large net-screened enclosures (8 by 5 by 2.8 m) built in a natural shaded environment, in the summers of 2006, 2007, 2008, and 2009 in northern Italy. Aedes albopictus (Skuse) males were radio-sterilized by applying gamma radiations at doses in the range 30-60 Gy. Gamma radiation was administered to aged pupae at the rate of 2.3 Gy/min. Reared radiated males (originally collected in Rimini, Forli, Bologna, Matera, Pinerolo) and hybrid radiated males were tested against wild fertile males (originated from eggs collected in Rimini and Cesena) and reared fertile males, in multiple comparisons for mating competitiveness with reared or wild females. The ratio was kept constant at 100-100_100 (fertile males-radiated males_virgin females). Mating competitiveness was estimated through the calculation of the hatching rate of the eggs laid in oviposition traps positioned inside enclosures. No clear effect of the strains tested (reared, wild, or hybrid) was found. Results demonstrated that reducing the radiation dose from 60 to 30 Gy increases males' competitiveness. Laboratory investigations conducted after controversial results in the 2006 preliminary trials, showed that radiation induces precociousness in adult male emergence.

  19. Spatial patterns of bacterial abundance, activity and community composition in relation to water masses in the eastern Mediterranean Sea

    NARCIS (Netherlands)

    Yokokawa, Taichi; De Corte, Daniele; Sintes, Eva; Herndl, Gerhard J.

    2010-01-01

    To determine the variation of bacterial activity and community composition between and within specific water masses, samples were collected throughout the water column at 5 stations in the eastern Mediterranean Sea corresponding to the regions of the northern Aegean, mid-Aegean, western Cretan,

  20. Cross-Mating Compatibility and Competitiveness among Aedes albopictus Strains from Distinct Geographic Origins - Implications for Future Application of SIT Programs in the South West Indian Ocean Islands.

    Science.gov (United States)

    Damiens, David; Lebon, Cyrille; Wilkinson, David A; Dijoux-Millet, Damien; Le Goff, Gilbert; Bheecarry, Ambicadutt; Gouagna, Louis Clément

    2016-01-01

    The production of large numbers of males needed for a sustainable sterile insect technique (SIT) control program requires significant developmental and operational costs. This may constitute a significant economic barrier to the installation of large scale rearing facilities in countries that are undergoing a transition from being largely dependent on insecticide use to be in a position to integrate the SIT against Aedes albopictus. Alternative options available for those countries could be to rely on outsourcing of sterile males from a foreign supplier, or for one centralised facility to produce mosquitoes for several countries, thus increasing the efficiency of the mass-rearing effort. However, demonstration of strain compatibility is a prerequisite for the export of mosquitoes for transborder SIT applications. Here, we compared mating compatibility among Ae. albopictus populations originating from three islands of the South Western Indian Ocean, and assessed both insemination rates and egg fertility in all possible cross-mating combinations. Furthermore, competitiveness between irradiated and non-irradiated males from the three studied strains, and the subsequent effect on female fertility were also examined. Although morphometric analysis of wing shapes suggested phenoptypic differences between Ae. albopictus strains, perfect reproductive compatibility between them was observed. Furthermore, irradiated males from the different islands demonstrated similar levels of competitiveness and induced sterility when confronted with fertile males from any of the other island populations tested. In conclusion, despite the evidence of inter-strain differences based on male wing morphology, collectively, our results provide a new set of expectations for the use of a single candidate strain of mass-reared sterile males for area-wide scale application of SIT against Ae. albopictus populations in different islands across the South Western Indian Ocean. Cross

  1. Phenomenological study of extended seesaw model for light sterile neutrino

    International Nuclear Information System (INIS)

    Nath, Newton; Ghosh, Monojit; Goswami, Srubabati; Gupta, Shivani

    2017-01-01

    We study the zero textures of the Yukawa matrices in the minimal extended type-I seesaw (MES) model which can give rise to ∼ eV scale sterile neutrinos. In this model, three right handed neutrinos and one extra singlet S are added to generate a light sterile neutrino. The light neutrino mass matrix for the active neutrinos, m ν , depends on the Dirac neutrino mass matrix (M D ), Majorana neutrino mass matrix (M R ) and the mass matrix (M S ) coupling the right handed neutrinos and the singlet. The model predicts one of the light neutrino masses to vanish. We systematically investigate the zero textures in M D and observe that maximum five zeros in M D can lead to viable zero textures in m ν . For this study we consider four different forms for M R (one diagonal and three off diagonal) and two different forms of (M S ) containing one zero. Remarkably we obtain only two allowed forms of m ν (m eτ =0 and m ττ =0) having inverted hierarchical mass spectrum. We re-analyze the phenomenological implications of these two allowed textures of m ν in the light of recent neutrino oscillation data. In the context of the MES model, we also express the low energy mass matrix, the mass of the sterile neutrino and the active-sterile mixing in terms of the parameters of the allowed Yukawa matrices. The MES model leads to some extra correlations which disallow some of the Yukawa textures obtained earlier, even though they give allowed one-zero forms of m ν . We show that the allowed textures in our study can be realized in a simple way in a model based on MES mechanism with a discrete Abelian flavor symmetry group Z 8 ×Z 2 .

  2. Displaced vertex searches for sterile neutrinos at future lepton colliders

    Energy Technology Data Exchange (ETDEWEB)

    Antusch, Stefan [Department of Physics, University of Basel, Klingelbergstr. 82, CH-4056 Basel (Switzerland); Max-Planck-Institut für Physik (Werner-Heisenberg-Institut),Föhringer Ring 6, D-80805 München (Germany); Cazzato, Eros; Fischer, Oliver [Department of Physics, University of Basel, Klingelbergstr. 82, CH-4056 Basel (Switzerland)

    2016-12-02

    We investigate the sensitivity of future lepton colliders to displaced vertices from the decays of long-lived heavy (almost sterile) neutrinos with electroweak scale masses and detectable time of flight. As future lepton colliders we consider the FCC-ee, the CEPC, and the ILC, searching at the Z-pole and at the center-of-mass energies of 240, 350 and 500 GeV. For a realistic discussion of the detector response to the displaced vertex signal and the Standard Model background we consider the ILC’s Silicon Detector (SiD) as benchmark for the future lepton collider detectors. We find that displaced vertices constitute a powerful search channel for sterile neutrinos, sensitive to squared active-sterile mixing angles as small as 10{sup −11}.

  3. Field performance of gamma irradiated and reared codling moth Cydia Pomonella (L.) males

    International Nuclear Information System (INIS)

    Mohamad, F.; Mansour, M.

    2003-04-01

    Marked males of codling moth, reared during immature stage on a local artificial diet, were released in two square plot (20 x 20 m) of two separate orchards. One of the orchard received sterile males exposed to 350 Gry (treatment), while the other received non-sterile males (control). To monitor the performance of sterile males compared to the control, pheromone traps were hung at certain distances (one trap/50 m) of the release site in each orchard, covering all four directions for 300 m. Traps up were checked daily for up to ten days after release. Results showed that number of control males was significantly less than sterile males at the first 50 m from the dispersion point (61.5% for control, 76.3% for treatment), Control males, however were captured more frequently at larger distance. For instance, the percentage for control and treated males were 17.2, 12.4% at 100 m, 10.4, 3.8% at 150 m and 7.2, 2.1% at 200 m respectively. A small percentage of control males (2.8%) reached 250 m, while treated males did not. These results indicate that sterile codling moth males exposed to a dose 350 Gy don't have the same dispersion ability as control ones. The results also show that the number of treated males responded to sex pheromone were less than control males in the first and second day after release, However they become more frequent in the third and fourth day, decreased in the fifth and stopped completely in day sixth. (author)

  4. Male irradiation affects female remating behavior in Anastrepha serpentina (Diptera: Tephritidae).

    Science.gov (United States)

    Landeta-Escamilla, Anais; Hernández, Emilio; Arredondo, José; Díaz-Fleischer, Francisco; Pérez-Staples, Diana

    2016-02-01

    Female remating in target pest species can affect the efficacy of control methods such as the Sterile Insect Technique (SIT) but very little is known about the postcopulatory mating behavior of these pests. In this study, we investigated the remating behavior of female Anastrepha serpentina (Diptera: Tephritidae), an oligophagous pest of Sapotaceae. First, we tested how long the sexual refractory period of females lasted after an initial mating. Second, we tested the effect of male and female sterility, female ovipositing opportunities and male density on female propensity to remate. Lastly, we tested if the amount of sperm stored by females was correlated to the likelihood of females to remate. We found that receptivity of mass-reared A. serpentina females had a bimodal response, with up to 16% of mass-reared A. serpentina females remating five days after the initial copulation, decreasing to 2% at 10 and 15 days and increasing to 13% after 20 days. Compared to fertile males, sterile males were less likely to mate and less likely to inhibit females from remating. Copula duration of sterile males was shorter compared to fertile males. Remating females were less likely to mate with a sterile male as a second mate. Sterile females were less likely to mate or remate compared to fertile females. Opportunity to oviposit and male density had no effect on female remating probability. Sperm numbers were not correlated with female likelihood to remate. Information on the post-copulatory behavior of mass-reared A. serpentina will aid fruit fly managers in improving the quality of sterile males. We discuss our results in terms of the differences this species presents in female remating behavior compared to other tephritids. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Efficacy of Blood Sources and Artificial Blood Feeding Methods in Rearing of Aedes aegypti (Diptera: Culicidae) for Sterile Insect Technique and Incompatible Insect Technique Approaches in Sri Lanka

    OpenAIRE

    Nayana Gunathilaka; Tharaka Ranathunge; Lahiru Udayanga; Wimaladharma Abeyewickreme

    2017-01-01

    Introduction Selection of the artificial membrane feeding technique and blood meal source has been recognized as key considerations in mass rearing of vectors. Methodology Artificial membrane feeding techniques, namely, glass plate, metal plate, and Hemotek membrane feeding method, and three blood sources (human, cattle, and chicken) were evaluated based on feeding rates, fecundity, and hatching rates of Aedes aegypti. Significance in the variations among blood feeding was investigated by one...

  6. Effects of sterile neutrino and extra-dimension on big bang nucleosynthesis

    Science.gov (United States)

    Jang, Dukjae; Kusakabe, Motohiko; Cheoun, Myung-Ki

    2018-04-01

    We study effects of the sterile neutrino in the five-dimensional universe on the big bang nucleosynthesis (BBN). Since the five-dimensional universe model leads to an additional term in the Friedmann equation and the energy density of the sterile neutrino increases the total energy density, this model can affect the primordial abundance via changing the cosmic expansion rate. The energy density of the sterile neutrino can be determined by a rate equation for production of the sterile neutrino. We show that not only the mixing angle and the mass of the sterile neutrino, but also a resonant effect in the oscillation between sterile and active neutrinos is important to determine a relic abundance of the sterile neutrino. In this study, we also investigate how the sterile neutrino in extra-dimensional model can affect the BBN, and constrain the parameters related to the above properties of the sterile neutrino by using the observational primordial abundances of light elements.

  7. Mass rearing of the melon fly in Okinawa, Japan - Special reference to quality control

    International Nuclear Information System (INIS)

    Yamagishii, Masaaki; Kakinohana, Hiroyuki

    2000-01-01

    The melon fly, Bactrocera cucurbitae (Coquillett), had been completely eradicated from Okinawa, Japan in 1993 (Yamagishi et al. 1993, Kakinohana 1994, Kuba et al. 1996). Following the expansion of target areas during the eradication campaign, the number of flies produced was increased from 5 million to 280 million per week. In the process of the eradication project, the mass reared strains had been replaced three times with new strains. The aim of this paper is to show the changes in various traits of the third strain that were regularly monitored in the factory. First, unintentional and intentional artificial selections to which the strain was exposed are mentioned. Second, the changes in the monitored traits are shown, and finally, the relation between selection and the response to selection is discussed

  8. Trends in sterilization since the introduction of Essure hysteroscopic sterilization.

    Science.gov (United States)

    Shavell, Valerie I; Abdallah, Mazen E; Shade, George H; Diamond, Michael P; Berman, Jay M

    2009-01-01

    To investigate trends in sterilization in women at the Detroit Medical Center, Michigan (DMC), since the introduction of Essure hysteroscopic sterilization. Retrospective study (Canadian Task Force classification II-2). Outpatient surgery center and university teaching hospitals. Women who underwent interval sterilization procedures at the DMC (Hutzel Women's Hospital, Sinai-Grace Hospital, and the Berry Center) and postpartum sterilization procedures at Hutzel Women's Hospital between January 1, 2002, and December 31, 2007. Permanent sterilization procedures including minilaparotomy tubal ligation, laparoscopic sterilization, Essure hysteroscopic sterilization, and postpartum tubal ligation performed at the time of cesarean section or after vaginal delivery. In all, 5509 permanent sterilization procedures were performed in the 6 years between January 1, 2002, and December 31, 2007, at the DMC facilities analyzed: 2484 interval sterilization procedures at Hutzel Women's Hospital, Sinai-Grace Hospital, and the Berry Center, and 3025 postpartum tubal ligations at Hutzel Women's Hospital. From 2002 through 2007, the decrease in laparoscopic sterilizations from 97.9% to 48.5% of all interval sterilization procedures corresponded significantly with the increase in Essure hysteroscopic sterilizations from 0.0% to 51.3% (p Essure hysteroscopic sterilizations increased significantly from 0.0% to 51.3% of all procedures. Since the approval of Essure hysteroscopic sterilization in November 2002, this minimally invasive method of hysteroscopic sterilization has increased in popularity at the DMC.

  9. Acoustic courtship songs in males of the fruit fly Anastrepha ludens (Diptera: Tephritidae associated with geography, mass rearing and courtship success

    Directory of Open Access Journals (Sweden)

    R.D Briceño

    2009-11-01

    Full Text Available The Sterile Insect Technique (SIT has been used successfully to control or eradicate fruit flies. The commonly observed inferiority of mass-reared males, compared with wild males, when they are paired with wild females, is apparently due to their inadequate courtship. Anastrepha ludens males produce two types of wing vibration during courtship and mating, the "calling sound" and the "premating or precopulatory sound". There were clear differences in the calling songs between successful and unsuccessful courtships in sterile (irradiated and fertile Mexican flies. Among sterile flies, successful males produce longer buzzes, shorter interpulses and a higher power spectrum in the signal. Fertile flies showed the same trend. For mating songs a significant difference occurred in two parameters: power spectrum between sterile and fertile flies with respect to the type of song, and the signal duration and intensity were greater in non-irradiated flies. Calling songs of wild flies compared with laboratory grown flies from Mexico had shorter interpulses, longer pulses, and a greater power spectrum. However, in the case of premating songs, the only difference was in the intensity, which was significantly greater in wild males. An unexpected result was not observing pulses during pheromone deposition in wild males from Costa Rica. Comparing the premating songs of wild flies from Costa Rica and Mexico, no significant differences were observed in the duration, and the intensity of the signal was slightly greater in flies from Mexico. Rev. Biol. Trop. 57 (Suppl. 1: 257-265. Epub 2009 November 30.La técnica estéril del insecto (SIT se ha utilizado con éxito para controlar o para suprimir las moscas de fruta y su impacto en los cultivos. La inferioridad comúnmente observada de machos criados masivamente, comparada con los machos silvestres, cuando se aparean con las hembras silvestres es al parecer debido a su inadecuado cortejo. Los machos de Anastrepha

  10. Mirror model for sterile neutrinos

    International Nuclear Information System (INIS)

    Berezinsky, Veniamin; Narayan, Mohan; Vissani, Francesco

    2003-01-01

    Sterile neutrinos are studied as subdominant contribution to solar neutrino physics. The mirror-matter neutrinos are considered as sterile neutrinos. We use the symmetric mirror model with gravitational communication between mirror and visible sectors. This communication term provides mixing between visible and mirror neutrinos with the basic scale μ=v EW 2 /M Pl =2.5x10 -6 eV, where v EW =174 GeV is the vacuum expectation value of the standard electroweak group and M Pl is the Planckian mass. It is demonstrated that each mass eigenstate of active neutrinos splits into two states separated by small Δm 2 . Unsuppressed oscillations between active and sterile neutrinos (ν a ↔ν s ) occur only in transitions between each of these close pairs ('windows'). These oscillations are characterized by very small Δm 2 and can suppress the flux and distort spectrum of pp-neutrinos in detectable way. The other observable effect is anomalous seasonal variation of neutrino flux, which appears in LMA solution. The considered subdominant neutrino oscillations ν a ↔ν s can reveal itself as big effects in observations of supernova neutrinos and high-energy (HE) neutrinos. In the case of HE neutrinos they can provide a very large diffuse flux of active neutrinos unconstrained by the e-m cascade upper limit

  11. Development of a rear wall for the KATRIN rear section and investigation of tritium compatibility of rear section components

    Energy Technology Data Exchange (ETDEWEB)

    Schoenung, Kerstin

    2016-01-15

    The aim of the KArlsruhe TRItium Neutrino experiment is to improve the current neutrino mass sensitivity limit to 0.2 eV/c{sup 2} (90%C.L.). For that, the required proof of suitability of several components for a low pressure tritium atmosphere is furnished. In addition, an optical design for an e-gun is developed and the resulting electron rate is calculated. Also, a final Rear Wall with temporally stable and homogeneous work function is developed and characterized within the scope of this thesis.

  12. Development of a Rear Wall for the KATRIN Rear Section and investigation of tritium compatibility of Rear Section components

    OpenAIRE

    Schönung, Kerstin

    2016-01-01

    The aim of the KArlsruhe TRItium Neutrino experiment is to improve the current neutrino mass sensitivity limit to 0.2 eV/c2 (90%C.L.). For that, the required proof of suitability of several components for a low pressure tritium atmosphere is furnished. In addition, an optical design for an e-gun is developed and the resulting electron rate is calculated. Also, a final Rear Wall with temporally stable and homogeneous work function is developed and characterized within the scope of this thesis.

  13. submitter Prospects of Sterile Neutrino Search with the FCC-ee

    CERN Document Server

    Bay Nielsen, Sissel

    A proposed future circular e + e − collider, the FCC-ee, is suggested to search for sterile neutrinos. The Neutrino Minimal Standard Model, νMSM, is a model of sterile neutrinos, that accommodates explanations for several phenomena of physics beyond the Standard Model. This thesis presents an overview of the theoretical motivation for νMSM, an outline of the experimental conditions at the FCC-ee, and a review of previous accelerator bounds for sterile neutrinos. Two studies of sterile neutrinos with masses at the electroweak scale are introduced, an analysis of long lived sterile neutrinos, and an analysis of short lived sterile neutrinos. Both analyses include background studies and sensitivity estimates for the FCC-ee detector. The study of long lived sterile neutrinos is based on a search for detectable displaced vertices with 1012 Z decays, obtaining a search reach on the mixing angle |θ| 2 as small as 10−11. The study of short lived sterile neutrinos is a Monte Carlo study with a cut-based analysi...

  14. Revisiting cosmological bounds on sterile neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Vincent, Aaron C. [Institute for Particle Physics Phenomenology (IPPP), Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Martínez, Enrique Fernández [Departamento and Instituto de Física Teórica (IFT), UAM/CSIC, Universidad Autonoma de Madrid, C/ Nicolás Cabrera 13-15, E-28049 Cantoblanco, Madrid (Spain); Hernández, Pilar; Mena, Olga [Instituto de Física Corpuscular (IFIC), CSIC-Universitat de València, Apartado de Correos 22085, E-46071 Valencia (Spain); Lattanzi, Massimiliano, E-mail: aaron.vincent@durham.ac.uk, E-mail: enrique.fernandez-martinez@uam.es, E-mail: m.pilar.hernandez@uv.es, E-mail: omena@ific.uv.es, E-mail: lattanzi@fe.infn.it [Dipartimento di Fisica e Science della Terra, Università di Ferrara and INFN, sezione di Ferrara, Polo Scientifico e Tecnologico, Edificio C Via Saragat, 1, I-44122 Ferrara (Italy)

    2015-04-01

    We employ state-of-the art cosmological observables including supernova surveys and BAO information to provide constraints on the mass and mixing angle of a non-resonantly produced sterile neutrino species, showing that cosmology can effectively rule out sterile neutrinos which decay between BBN and the present day. The decoupling of an additional heavy neutrino species can modify the time dependence of the Universe's expansion between BBN and recombination and, in extreme cases, lead to an additional matter-dominated period; while this could naively lead to a younger Universe with a larger Hubble parameter, it could later be compensated by the extra radiation expected in the form of neutrinos from sterile decay. However, recombination-era observables including the Cosmic Microwave Background (CMB), the shift parameter R{sub CMB} and the sound horizon r{sub s} from Baryon Acoustic Oscillations (BAO) severely constrain this scenario. We self-consistently include the full time-evolution of the coupled sterile neutrino and standard model sectors in an MCMC, showing that if decay occurs after BBN, the sterile neutrino is essentially bounded by the constraint sin{sup 2}θ ∼< 0.026 (m{sub s}/eV){sup −2}.

  15. Sterile neutrinos in lepton number and lepton flavor violating decays

    International Nuclear Information System (INIS)

    Helo, Juan Carlos; Kovalenko, Sergey; Schmidt, Ivan

    2011-01-01

    We study the contribution of massive dominantly sterile neutrinos, N, to the lepton number and lepton flavor violating semileptonic decays of τ and B, D, K-mesons. We focus on special domains of sterile neutrino masses m N where it is close to its mass-shell. This leads to an enormous resonant enhancement of the decay rates of these processes. This allows us to derive stringent limits on the sterile neutrino mass m N and its mixing U αN with active flavors. We apply a joint analysis of the existing experimental bounds on the decay rates of the studied processes. In contrast to other approaches in the literature our limits are free from ad hoc assumptions on the relative size of the sterile neutrino mixing parameters. We analyze the impact of this sort of assumptions on the extraction of the limits on m N and U αN , and discuss the effect of finite detector size. Special attention was paid to the limits on meson decays with e ± e ± in final state, derived from non-observation of 0νββ-decay. We point out that observation of these decays may, in particular, shed light on the Majorana phases of the neutrino mixing matrix.

  16. Sterile Neutrino Search with the Double Chooz Experiment

    Science.gov (United States)

    Hellwig, D.; Matsubara, T.; Double Chooz Collaboration

    2017-09-01

    Double Chooz is a reactor antineutrino disappearance experiment located in Chooz, France. A far detector at a distance of about 1 km from reactor cores is operating since 2011; a near detector of identical design at a distance of about 400 m is operating since begin 2015. Beyond the precise measurement of θ 13, Double Chooz has a strong sensitivity to so called light sterile neutrinos. Sterile neutrinos are neutrino mass states not taking part in weak interactions, but may mix with known neutrino states. In this paper, we present an analysis method to search for sterile neutrinos and the expected sensitivity with the baselines of our detectors.

  17. Device and Container for Reheating and Sterilization

    Science.gov (United States)

    Sastry, Sudhir K.; Heskitt, Brian F.; Jun, Soojin; Marcy, Joseph E.; Mahna, Ritesh

    2012-01-01

    Long-duration space missions require the development of improved foods and novel packages that do not represent a significant disposal issue. In addition, it would also be desirable if rapid heating technologies could be used on Earth as well, to improve food quality during a sterilization process. For this purpose, a package equipped with electrodes was developed that will enable rapid reheating of contents via ohmic heating to serving temperature during space vehicle transit. Further, the package is designed with a resealing feature, which enables the package, once used, to contain and sterilize waste, including human waste for storage prior to jettison during a long-duration mission. Ohmic heating is a technology that has been investigated on and off for over a century. Literature indicates that foods processed by ohmic heating are of superior quality to their conventionally processed counterparts. This is due to the speed and uniformity of ohmic heating, which minimizes exposure of sensitive materials to high temperatures. In principle, the material may be heated rapidly to sterilization conditions, cooled rapidly, and stored. The ohmic heating device herein is incorporated within a package. While this by itself is not novel, a reusable feature also was developed with the intent that waste may be stored and re-sterilized within the packages. These would then serve a useful function after their use in food processing and storage. The enclosure should be designed to minimize mass (and for NASA's purposes, Equivalent System Mass, or ESM), while enabling the sterilization function. It should also be electrically insulating. For this reason, Ultem high-strength, machinable electrical insulator was used.

  18. Cosmological lepton asymmetry, primordial nucleosynthesis and sterile neutrinos

    Science.gov (United States)

    Abazajian, Kevork; Bell, Nicole F.; Fuller, George M.; Wong, Yvonne Y. Y.

    2005-09-01

    We study post weak decoupling coherent active-sterile and active-active matter-enhanced neutrino flavor transformation in the early Universe. We show that flavor conversion efficiency at Mikheyev-Smirnov-Wolfenstein resonances is likely to be high (adiabatic evolution) for relevant neutrino parameters and energies. However, we point out that these resonances cannot sweep smoothly and continuously with the expansion of the Universe. We show how neutrino flavor conversion in this way can leave both the active and sterile neutrinos with nonthermal energy spectra, and how, in turn, these distorted energy spectra can affect the neutron-to-proton ratio, primordial nucleosynthesis, and cosmological mass/closure constraints on sterile neutrinos. We demonstrate that the existence of a light sterile neutrino which mixes with active neutrinos can change fundamentally the relationship between the cosmological lepton numbers and the primordial nucleosynthesis He4 yield.

  19. Environment-dependent plasticity and ontogenetic changes in the brain of hatchery-reared Atlantic salmon

    DEFF Research Database (Denmark)

    Näslund, J.; Larsen, Martin Hage; Thomassen, S.T.

    2017-01-01

    enhancement strategies, like environmental enrichment. Here, we investigated the size of the brain in hatcheryreared Atlantic salmon Salmo salar kept at standard (high) and reduced (low) tank densities. In contrast to our predictions, we found that fish reared at high density had larger dry mass of cerebellum...... and telencephalon, correcting for body size. No differences were detected for total brain mass. Furthermore, we found that the relative size of both telencephalon and cerebellum, in relation to total brain mass, changed with body size. Cerebellum increased in relative size with increased body size, while......Lowered rearing density has repeatedly been shown to increase the performance of hatchery-reared salmonids stocked into natural environments. One possible mechanism for this pattern could be that lower densities enhance brain development, which has been shown to be the case in other hatchery...

  20. Pulsar kicks from a dark-matter sterile neutrino

    International Nuclear Information System (INIS)

    Fuller, George M.; Kusenko, Alexander; Mocioiu, Irina; Pascoli, Silvia

    2003-01-01

    We show that a sterile neutrino with a mass in the 1-20 keV range and a small mixing with the electron neutrino can simultaneously explain the origin of the pulsar motions and the dark matter in the Universe. An asymmetric neutrino emission from a hot nascent neutron star can be the explanation of the observed pulsar velocities. In addition to the pulsar kick mechanism based on resonant neutrino transitions, we point out a new possibility: an asymmetric off-resonant emission of sterile neutrinos. The two cases correspond to different values of the masses and mixing angles. In both cases we identify the ranges of parameters consistent with the pulsar kick, as well as cosmological constraints

  1. How self-interactions can reconcile sterile neutrinos with cosmology.

    Science.gov (United States)

    Hannestad, Steen; Hansen, Rasmus Sloth; Tram, Thomas

    2014-01-24

    Short baseline neutrino oscillation experiments have shown hints of the existence of additional sterile neutrinos in the eV mass range. However, such neutrinos seem incompatible with cosmology because they have too large of an impact on cosmic structure formation. Here we show that new interactions in the sterile neutrino sector can prevent their production in the early Universe and reconcile short baseline oscillation experiments with cosmology.

  2. Determination of the dose of gamma radiation sterilization for assessment of biological parameters of male Ceratitis capitada (Diptera: Tephritidae), tsl - Vienna 8 strain; Determinacao da dose de radiacao gama esterilizante pela avaliacao dos parametros biologicos de machos de Ceratitis capitata (Diptera: Tephritidae), linhagem tsl - Vienna 8

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Aline Cristina Pereira da

    2011-07-01

    The Vienna-8, tsl (temperature sensitive lethal) strain of Ceratitis capitata, by presenting mutations that facilitate the mass rearing and release only of sterile males in the field, has been used in (Sterile Insect Technique) programmes. The objective of this study was to determine the radiation dose that provides the highest level of sterility for Vienna-8, tsl males assessing their biological parameters that indicate the quality of sterile males to be released. Brown pupae (males) of the tsl strain were obtained from the mass rearing of the Food Irradiation and Radio entomology laboratory of CENA/USP, and they were irradiated (with gamma radiation - {sup 60}Co) 24 hours before the emergence at rates of 0, 30, 60, 90 and 120 Gy. The determination of the sterilizing dose was based on fertility of sexually mature females of the bisexual strain and not irradiated, mated with males of different treatments. Eggs were collected daily during 6 days, were counted and it was possible to estimate fecundity, and assess the hatching rate. The emergence and flight ability were determined by following the protocol of quality control manual for FAO/IAEA/USDA (2003). To assess the longevity under nutritional stress, the insects were kept a period of 48 h after emergence in the absence of water and food, and after this period, mortality was recorded. The size of the testes (left and right) was obtained by dissecting irradiated and non-irradiated males at the eighth day of life, and measure the testes in an ocular micrometer, considering the maximum length and width of each sample. To determine the sperm number was necessary to dissect the males and break their testicles. No difference was observed in emergence rate, flight ability and longevity of irradiated and non-irradiated males, nor in the fecundity of females mated with males of different treatments. The sterilizing dose that resulted in lower fertility of females was 120 Gy, with 1.5% hatching. Considering the parameters

  3. Field trials for the control of the Mediterranean fruit-fly by radiation induced sterility. Part of a coordinated programme on fruit-fly eradication of control by the sterile-male technique

    International Nuclear Information System (INIS)

    Mellado, L.; Arroyo, M.; Jimenez, A.; Ros, P.; Caballero, F.; Vargas, C.

    1975-12-01

    More than 50 million insects were used in field trials in which the applicability of the sterile insects release method to the control of Ceratitis capitata in Spain was tested. The areas concerned were Santa Fe, Purchil and Armilla. Whereas the infestation of untreated areas (controls) was 92 %, chemically treated areas (using Lebaycid and other insecticides) ranged from 1.2 to 17 %, and areas over which sterile insects had been released showed less than 1.3 % infestation. The economic aspects and advantages of the sterile insect method compared with chemical control measures are pointed out

  4. Evidence and Search for Sterile Neutrinos at Accelerators

    Directory of Open Access Journals (Sweden)

    W. C. Louis

    2013-01-01

    Full Text Available The LSND short-baseline neutrino experiment has published evidence for antineutrino oscillations at a mass scale of ~1 eV2. The MiniBooNE experiment, designed to test this evidence for oscillations at an order of magnitude higher neutrino energy and distance, observes excesses of events in both neutrino mode and antineutrino mode. While the MiniBooNE neutrino excess has a neutrino energy spectrum that is softer than expected from LSND, the MiniBooNE antineutrino excess is consistent with neutrino oscillations and with the LSND oscillation signal. When combined with oscillation measurements at the solar and atmospheric mass scales, assuming that the LSND and MiniBooNE signals are due to neutrino oscillations, these experiments imply the existence of more than three neutrino mass states and, therefore, one or more sterile neutrinos. Such sterile neutrinos, if proven to exist, would have a big impact on particle physics, nuclear physics, and astrophysics and would contribute to the dark matter of the universe. Future experiments under construction or proposed at Fermilab, ORNL, CERN, and in Japan will provide a definitive test of short-baseline neutrino oscillations and will have the capability of proving the existence of sterile neutrinos.

  5. Sterile Neutrino Search in the NOvA Far Detector

    Energy Technology Data Exchange (ETDEWEB)

    Edayath, Sijith [Cochin U.; Aurisano, Adam [Cincinnati U.; Sousa, Alexandre [Cincinnati U.; Davies, Gavin [Indiana U.; Suter, Louise [Fermilab; Yang, Shaokai [Cincinnati U.

    2017-10-03

    The majority of neutrino oscillation experiments have obtained evidence for neutrino oscillations that are compatible with the three-flavor model. Explaining anomalous results from short-baseline experiments, such as LSND and MiniBooNE, in terms of neutrino oscillations requires the existence of sterile neutrinos. The search for sterile neutrino mixing conducted in NOvA uses a long baseline of 810 km between Near Detector (ND) at Fermilab and Far Detector (FD) in Minnesota. The signal for sterile neutrino oscillations is a deficit of neutral-current neutrino interactions at the FD with respect to the ND prediction. In this document, We will present the analysis improvements that we are implementing for future NC sterile neutrino searches with NOvA. These include: improved modelling of our detector response; the inclusion of NC 2p2h interaction modelling; implementing a better energy reconstruction techniques; and including possible oscillation due to sterile neutrinos in the ND . This improvements enable us to do a simultaneous ND-FD shape fit of the NC energy spectrum covering a wider sterile mass range than previous analyses.

  6. Phenomenological study of extended seesaw model for light sterile neutrino

    Energy Technology Data Exchange (ETDEWEB)

    Nath, Newton [Physical Research Laboratory,Navarangpura, Ahmedabad 380 009 (India); Indian Institute of Technology,Gandhinagar, Ahmedabad-382424 (India); Ghosh, Monojit [Department of Physics, Tokyo Metropolitan University,Hachioji, Tokyo 192-0397 (Japan); Goswami, Srubabati [Physical Research Laboratory,Navarangpura, Ahmedabad 380 009 (India); Gupta, Shivani [Center of Excellence for Particle Physics (CoEPP), University of Adelaide,Adelaide SA 5005 (Australia)

    2017-03-14

    We study the zero textures of the Yukawa matrices in the minimal extended type-I seesaw (MES) model which can give rise to ∼ eV scale sterile neutrinos. In this model, three right handed neutrinos and one extra singlet S are added to generate a light sterile neutrino. The light neutrino mass matrix for the active neutrinos, m{sub ν}, depends on the Dirac neutrino mass matrix (M{sub D}), Majorana neutrino mass matrix (M{sub R}) and the mass matrix (M{sub S}) coupling the right handed neutrinos and the singlet. The model predicts one of the light neutrino masses to vanish. We systematically investigate the zero textures in M{sub D} and observe that maximum five zeros in M{sub D} can lead to viable zero textures in m{sub ν}. For this study we consider four different forms for M{sub R} (one diagonal and three off diagonal) and two different forms of (M{sub S}) containing one zero. Remarkably we obtain only two allowed forms of m{sub ν} (m{sub eτ}=0 and m{sub ττ}=0) having inverted hierarchical mass spectrum. We re-analyze the phenomenological implications of these two allowed textures of m{sub ν} in the light of recent neutrino oscillation data. In the context of the MES model, we also express the low energy mass matrix, the mass of the sterile neutrino and the active-sterile mixing in terms of the parameters of the allowed Yukawa matrices. The MES model leads to some extra correlations which disallow some of the Yukawa textures obtained earlier, even though they give allowed one-zero forms of m{sub ν}. We show that the allowed textures in our study can be realized in a simple way in a model based on MES mechanism with a discrete Abelian flavor symmetry group Z{sub 8}×Z{sub 2}.

  7. Sterile neutrino constraints from cosmology

    DEFF Research Database (Denmark)

    Hamann, Jan; Hannestad, Steen; Raffelt, Georg G.

    2012-01-01

    The presence of light particles beyond the standard model's three neutrino species can profoundly impact the physics of decoupling and primordial nucleosynthesis. I review the observational signatures of extra light species, present constraints from recent data, and discuss the implications of po...... of possible sterile neutrinos with O(eV)-masses for cosmology....

  8. A highly stable blood meal alternative for rearing Aedes and Anopheles mosquitoes.

    Directory of Open Access Journals (Sweden)

    Ted Baughman

    2017-12-01

    Full Text Available We investigated alternatives to whole blood for blood feeding of mosquitoes with a focus on improved stability and compatibility with mass rearing programs. In contrast to whole blood, an artificial blood diet of ATP-supplemented plasma was effective in maintaining mosquito populations and was compatible with storage for extended periods refrigerated, frozen, and as a lyophilized powder. The plasma ATP diet supported rearing of both Anopheles and Aedes mosquitoes. It was also effective in rearing Wolbachia-infected Aedes mosquitoes, suggesting compatibility with vector control efforts.

  9. Coherent Active-Sterile Neutrino Flavor Transformation in the Early Universe

    Science.gov (United States)

    Kishimoto, Chad T.; Fuller, George M.; Smith, Christel J.

    2006-10-01

    We solve the problem of coherent Mikheyev-Smirnov-Wolfenstein resonant active-to-sterile neutrino flavor conversion driven by an initial lepton number in the early Universe. We find incomplete destruction of the lepton number in this process and a sterile neutrino energy distribution with a distinctive cusp and high energy tail. These features imply alteration of the nonzero lepton number primordial nucleosynthesis paradigm when there exist sterile neutrinos with rest masses ms˜1eV. This could result in better light element probes of (constraints on) these particles.

  10. Coherent Active-Sterile Neutrino Flavor Transformation in the Early Universe

    International Nuclear Information System (INIS)

    Kishimoto, Chad T.; Fuller, George M.; Smith, Christel J.

    2006-01-01

    We solve the problem of coherent Mikheyev-Smirnov-Wolfenstein resonant active-to-sterile neutrino flavor conversion driven by an initial lepton number in the early Universe. We find incomplete destruction of the lepton number in this process and a sterile neutrino energy distribution with a distinctive cusp and high energy tail. These features imply alteration of the nonzero lepton number primordial nucleosynthesis paradigm when there exist sterile neutrinos with rest masses m s ∼1 eV. This could result in better light element probes of (constraints on) these particles

  11. Steric and mass-induced Mediterranean sea level trends from 14 years of altimetry data

    Science.gov (United States)

    Criado-Aldeanueva, Francisco; Del Río Vera, Jorge; García-Lafuente, Jesús

    2008-02-01

    Long-term series of almost 14 years of altimetry data (1992-2005) have been analysed along with Sea Surface Temperature (SST) and temperature and salinity profiles to investigate sea level trends over the Mediterranean Sea. Although sea level variations are mainly driven by the steric contribution, the mass-induced component plays some role in modulating its oscillation. A spatially averaged positive trend of 2.1 ± 0.6 mm/year has been observed, but a change in sign in 2001 seems to appear. Steric effects (mainly on thermal origin) account for ˜ 55% of sea level trend. Although Mediterranean Sea is a semi-enclosed basin, this value is comparable to that reported for the global ocean. Sea level rise is particularly important in the Levantine basin south of Crete with values up to 10 ± 1 mm/year. Other areas of sea level rise are localised throughout the Levantine basin and in the Adriatic and Alboran Seas, with more moderate values. Sea level drop areas are localised in the Algerian basin, between the Balearic Islands and the African coasts and, particularly, in the Ionian basin. In this area, negative trends as high as - 10 ± 0.8 mm/year are detected mainly due to the mass-induced contribution, which suggests decadal changes of surface circulation. The inferred sea level trends have been correlated with North Atlantic Oscillation (NAO) indices and a low but significant correlation has been detected between sea level in the Levantine and Balearic basins and NAO index.

  12. Difficulties and Successes in the Mass Rearing of Insects in the Laboratory, and the Possibility of Autocidal Control of some Harmful Species; Trudnosti i uspekhi massovogo razvedeniya nasekomykh v laboratorii i vozmozhnosti samoistrebleniya nekotorykh vrednykh vidov

    Energy Technology Data Exchange (ETDEWEB)

    Shumakov, E. M. [Rastenij, Vsesojuznyj Nauchno-Issledovatel' skij Institut Zashhity Leningrad, SSSR (Russian Federation)

    1968-06-15

    The practical development of the sterile-male release technique, as indeed of all methods of autocidal control of harmful insects, is limited by the difficulties of mass rearing in artificial conditions. However, analysis of cases of the successful solution of this problem for a number of types of Diptera, Lepidoptera and Orthoptera gives an indication of possible ways of setting up large-scale rearing of the insects required. The most difficult problem, that of ensuring a suitable food supply for the insects at any time of the year, is being successfully overcome as a result of the progress made in producing synthetic and semi- synthetic nutrient media, which have been developed both for semi-saprophytic and for herbivorous and predacious species. The choice of recipes for such nutrients is determined by correct selection of the necessary ingredients, above all vitamins, free amino acids and sterols; the proper quantitative proportion between these substances and between the basic components of the food - proteins, fats and hydrocarbons - is of the greatest importance. The amount of work involved in insect rearing depends on what means are used for sterilizing the containers and for preventing the nutrient medium from decaying. One way in which these problems have been solved is by the development of a dried nutrient medium in powder form; this has been successfully used for rearing the migratory locust in the USSR. For a number of harmful species of Lepidoptera, it has been shown possible to rear the insects in a closed, sealed container. In this case a supply of nutrient medium is provided adequate to ensure the insects' development from, the time the eggs or caterpillars are deposited until the imago of the new generation emerges. This approach greatly simplifies the whole process of mass rearing. Many species of insects can be reared on grain or plant seeds which are less subject to decay during prolonged storage. Another important problem is that of

  13. Development and application of genetic sexing systems for the Mediterranean fruit fly based on a temperature sensitive lethal mutation

    International Nuclear Information System (INIS)

    Franz, G.; Willhoeft, U.; Kerremans, P.; Hendrichs, J.; Rendon, P.

    1997-01-01

    The present status in genetic sexing for the Mediterranean fruit fly is discussed. This includes the selection of the appropriate sexing gene (which determines the feasibility and practical applicability of the sexing system) as well as the selection of the appropriate Y-autosome translocation (which determines the stability of the sexing system). A temperature sensitive lethal mutation is used to eliminate females during the egg stage. This mutation in combination with new Y-autosome translocations allowed the construction of a genetic sexing strain, named VIENNA-42, that is stable enough for large scale mass rearing. Also described are the analysis of this strain under field cage and field conditions and, in preparation for large scale tests in Guatemala, the outcrossing of VIENNA-42 with genetic material from the target area. (author)

  14. Biological Studies On The Radioprotective Role Of Melatonin On The Medfly Ceratitis Capitata (WIED.), Sterile Males

    International Nuclear Information System (INIS)

    SHOMAN, A.A.; MAHMOUD, E.A.

    2010-01-01

    The sterile insect technique (SIT) has been used successfully against the medfly. The use of gamma irradiation for sterilizing insects has some adverse effects on their competitiveness which in turn reduces the efficiency of the technique. This study was carried out to evaluate the radioprotective effects of melatonin (N-acetyl-5-methoxytyrptamine) on egg hatchability, larval duration, pupal recovery, pupal weight, adult recovery, sex ratio, adult survival, flight ability and mating competitiveness of the medfly, Ceratitis capitata (Wied.), sterile males against the oxidative stress induced by gamma radiation. The results showed that the use of melatonin before the application of radiation doses did not affect the percentages of egg hatchability, larval duration and pupal weight while the addition of melatonin to the larval diet led to a significant increase in the percent of the pupal recovery as compared with the control group. The results also showed significant increases in adult recovery, adult survival and flight ability of males reared on larval diet containing melatonin before irradiation as compared to those treated with radiation alone. The competitiveness values were drastically decreased (0.30, 0.17 and 0.19) with the increase of gamma irradiation (90, 100 and 110 Gy, respectively). However, the results showed that the competitiveness values were increased in males previously reared on a larval diet containing 1 g melatonin/kg larval media (0.1%) and the produced full grown pupae were irradiated with 90, 100 and 110 Gy. The highest male mating competitiveness was recorded when melatonin was added to the larval diet then irradiated the produced pupae with the sterilizing dose (90 Gy). The results showed that the competitiveness values were 0.67, 0.47 and 0.46 for the doses 90, 100 and 110 Gy, respectively. The results refer to availability of using melatonin as a simple and effective means to improve the quality and the male mating competitiveness of the

  15. Psychiatric Status across Body Mass Index in a Mediterranean Spanish Population.

    Directory of Open Access Journals (Sweden)

    Mario Gutiérrez-Bedmar

    Full Text Available Mental and body weight disorders are among the major global health challenges, and their comorbidity may play an important role in treatment and prevention of both pathologies. A growing number of studies have examined the relationship between psychiatric status and body weight, but our knowledge is still limited.The present study aims to investigate the cross-sectional relationships of psychiatric status and body mass index (BMI in Málaga, a Mediterranean city in the South of Spain.A total of 563 participants were recruited from those who came to his primary care physician, using a systematic random sampling, non-proportional stratified by BMI categories. Structured clinical interviews were used to assess current Axes-I and II mental disorders according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR. BMI was calculated as weight (Kg divided by square of height in meters (m2. Logistic regression was used to investigate the association between BMI and the presence of any mental disorder. BMI was introduced in the models using restricted cubic splines.We found that high BMI values were directly associated with mood and adjustment disorders, and low BMI values were directly associated with avoidant and dependent personality disorders (PDs. We observed an inverse relationship between low BMI values and cluster A PDs. There were not significant relationships between anxiety or substance-related disorders and BMI.Psychiatric status and BMI are related in a Mediterranean Spanish population. A multidisciplinary approach to both pathologies becomes increasingly more necessary.

  16. Reionization in sterile neutrino cosmologies

    Science.gov (United States)

    Bose, Sownak; Frenk, Carlos S.; Hou, Jun; Lacey, Cedric G.; Lovell, Mark R.

    2016-12-01

    We investigate the process of reionization in a model in which the dark matter is a warm elementary particle such as a sterile neutrino. We focus on models that are consistent with the dark matter decay interpretation of the recently detected line at 3.5 keV in the X-ray spectra of galaxies and clusters. In warm dark matter models, the primordial spectrum of density perturbations has a cut-off on the scale of dwarf galaxies. Structure formation therefore begins later than in the standard cold dark matter (CDM) model and very few objects form below the cut-off mass scale. To calculate the number of ionizing photons, we use the Durham semi-analytic model of galaxy formation, GALFORM. We find that even the most extreme 7 keV sterile neutrino we consider is able to reionize the Universe early enough to be compatible with the bounds on the epoch of reionization from Planck. This, perhaps surprising, result arises from the rapid build-up of high redshift galaxies in the sterile neutrino models which is also reflected in a faster evolution of their far-UV luminosity function between 10 > z > 7 than in CDM. The dominant sources of ionizing photons are systematically more massive in the sterile neutrino models than in CDM. As a consistency check on the models, we calculate the present-day luminosity function of satellites of Milky Way-like galaxies. When the satellites recently discovered in the Dark Energy Survey are taken into account, strong constraints are placed on viable sterile neutrino models.

  17. In vita and at slaughter performances of kids naturally reared in Molise

    Directory of Open Access Journals (Sweden)

    E. Salimei

    2011-03-01

    Full Text Available The world importance of goat husbandry as a genetic source for the production of meat, milk, textile fibre and skin, especially in tropical and sub-tropical areas and in Developing Countries is wide documented (Husain et al., 1996. Goat rearing annually produce about 177.6 millions tons of milk (FAO, 1992 and about 3.5 millions tons of meat (FAO, 1996, with an increasing request of product, that in the last decade has driven the increase of the number of heads reared (Knights et al., 1997. Because of the peculiar behaviour of goats, the above mentioned increase has been observed mainly in Developing Countries as well as in marginal lands of the Mediterranean areas (Southern Italy and Greece, in particular. In Molise, for instance, an increase in goats consistency has been recorded over 15 years (AIA, 1997. The emerging requests by the final consumer of typical and healthy products with origin and quality certified have also contributed to the survival of certain goats population as an exploitation tool of marginal lands, otherwise voted to be abandoned...

  18. Alternate Mediterranean diet score is positively associated with skeletal muscle mass index in middle-aged adults.

    Science.gov (United States)

    Tian, Hui-Yuan; Qiu, Rui; Jing, Li-Peng; Chen, Zhan-Yong; Chen, Geng-Dong; Chen, Yu-Ming

    2017-04-01

    Researches have suggested Mediterranean diet might lower the risk of chronic diseases, but data on skeletal muscle mass (SMM) are limited. This community-based cross-sectional study examined the association between the alternate Mediterranean diet score (aMDS) and SMM in 2230 females and 1059 males aged 40-75 years in Guangzhou, China. General information and habitual dietary information were assessed in face-to-face interviews conducted during 2008-2010 and 3 years later. The aMDS was calculated by summing the dichotomous points for the items of higher intakes of whole grain, vegetables, fruits, legumes, nuts, fish and ratio of MUFA:SFA, lower red meat and moderate ethanol consumption. The SMM of the whole body, limbs, arms and legs were measured using dual-energy X-ray absorptiometry during 2011-2013. After adjusting for potential covariates, higher aMDS was positively associated with skeletal muscle mass index (SMI, SMM/height2, kg/m2) at all of the studied sites in males (all P trend0·05). Age-stratified analyses showed that the favourable associations tended to be more pronounced in the younger subjects aged less than the medians of 59·2 and 62·2 years in females and males (P interaction>0·10). In conclusion, the aMDS shows protective associations with SMM in Chinese adults, particularly in male and younger subjects.

  19. Impact of sterile neutrinos on nuclear-assisted cLFV processes

    Energy Technology Data Exchange (ETDEWEB)

    Abada, A. [Laboratoire de Physique Théorique, CNRS,University Paris-Sud, Université Paris-Saclay, 91405 Orsay (France); Romeri, V. De; Teixeira, A.M. [Laboratoire de Physique Corpusculaire, CNRS/IN2P3 - UMR 6533,Campus des Cézeaux, 24 Av. des Landais, F-63177 Aubière Cedex (France)

    2016-02-12

    We discuss charged lepton flavour violating processes occurring in the presence of muonic atoms, such as muon-electron conversion in nuclei CR(μ−e, N), the (Coulomb enhanced) decay of muonic atoms into a pair of electrons BR(μ{sup −}e{sup −}→e{sup −}e{sup −}, N), as well as Muonium conversion and decay, Mu− (Mu)-bar and Mu→e{sup +}e{sup −}. Any experimental signal of these observables calls for scenarios of physics beyond the Standard Model. In this work, we consider minimal extensions of the Standard Model via the addition of sterile fermions, providing the corresponding complete analytical expressions for all the considered observables. We first consider an “ad hoc” extension with a single sterile fermion state, and investigate its impact on the above observables. Two well motivated mechanisms of neutrino mass generation are then considered: the Inverse Seesaw embedded into the Standard Model, and the νMSM. Our study reveals that, depending on their mass range and on the active-sterile mixing angles, sterile neutrinos can give significant contributions to the above mentioned observables, some of them even lying within present and future sensitivity of dedicated cLFV experiments. We complete the analysis by confronting our results to other (direct and indirect) searches for sterile fermions.

  20. Establishment of a colony of Anastrepha ludens (Diptera: Tephritidae) under relaxed mass-rearing conditions in Mexico

    International Nuclear Information System (INIS)

    Orozco-Davila, Dina; Hernandez, Refugio; Solis, Eduardo; Quintero, J. Luis; Dominguez, Julio

    2006-01-01

    Several studies have suggested that maintaining a line of insects under laboratory conditions reduces their biological attributes. With this principle in mind, the mass production of Anastrepha ludens originating from a colony raised under relaxed rearing conditions was evaluated over a period of three years. The results of the evaluation indicated that insects kept under these conditions reached their larval maturity in 10 days, and attained a greater weight, which has a direct influence on pupal quality. In adult cages having a fly density of 70,000 individuals, there was a lower level of stress which favored fecundity. Fertility was apparently not affected by the cage density. These results suggest that keeping a production line under relaxed conditions optimizes insect production and promotes higher quality. (author)

  1. Establishment of a colony of Anastrepha ludens (Diptera: Tephritidae) under relaxed mass-rearing conditions in Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Orozco-Davila, Dina; Hernandez, Refugio; Solis, Eduardo; Quintero, J. Luis; Dominguez, Julio, E-mail: dorozco1@prodigy.net.m [United States Department of Agriculture, Gainesville, FL (United States). Agricultural Research Service. Center for Medical, Agricultural, and Veterinary Entomology; Sigma Space Corporation, MD(United States); Programa Moscamed Moscafrut-Desarrollo de Metodos, Chiapas (Mexico)

    2006-07-01

    Several studies have suggested that maintaining a line of insects under laboratory conditions reduces their biological attributes. With this principle in mind, the mass production of Anastrepha ludens originating from a colony raised under relaxed rearing conditions was evaluated over a period of three years. The results of the evaluation indicated that insects kept under these conditions reached their larval maturity in 10 days, and attained a greater weight, which has a direct influence on pupal quality. In adult cages having a fly density of 70,000 individuals, there was a lower level of stress which favored fecundity. Fertility was apparently not affected by the cage density. These results suggest that keeping a production line under relaxed conditions optimizes insect production and promotes higher quality. (author)

  2. Radiation sterilization

    International Nuclear Information System (INIS)

    Jacobs, G.P.

    1989-01-01

    In view of the application of ionizing radiation to sterilize pharmaceutical products, and the particular advantages of using this mode of sterilization for powders for injection, which cannot be sterilized by more conventional methods, it is important to recognise the possibility of modification of radiation response of bacteria when in close contact with various drug powders. For this study, bacterial spores, which lend themselves to dessication, and which can be dried onto an inert powder matrix, were chosen as the test system. The results of this work indicate that the additives tested have a modest protective effect on the spores. However, when considering a bacterial inactivation for sterilization purposes of between six and ten orders of magnitude, that is, a desired sterility assurance level of an expected maximum probability of a product item being non-sterile of 10 -6 , then the slight protective effect observed in this study approaches insignificance

  3. Sterilizing effects and lethal effects of gamma radiation on different phases of life cycle of the sitotroga cerealella (Olivier) in rice and maize

    International Nuclear Information System (INIS)

    Arthur, V.

    1985-01-01

    The objective of this research to verify the effects of the gamma radiation on different phases of the life cycle of the gamma radiation on different phases of the life cycle of the moth grain Angoumois, Sitotroga cerealella (Olivier, 1819). For all the treatment with gamma radiation a Cobalt-60 source type Gammabeam-650 was used and the activity was approximately 3.1 x 10 sup(14) Bq., with dose rate of 3.01 kGy per hour. The LD sub(100) of gamma radiation for eggs of insects reared in rice and maize were respectively 100 Gy and 125 Gy. The sterilizing doses in adults which were irradiated at immature phases (larvae and pupae) were 100 Gy and 200 Gy in rice and 150 Gy and 250 Gy in maize, respectively. The sterilizing doses for females and males in maize were respectively 350 Gy and 500 Gy. The LD sub(100) for adult females were 4500 Gy and 4750 Gy for males, both in rice. The LD sub(100), for adult reared on maize was 4750 Gy for both sexes. (author)

  4. Wing Morphometry and Acoustic Signals in Sterile and Wild Males: Implications for Mating Success in Ceratitis capitata

    Directory of Open Access Journals (Sweden)

    João Maria Gomes Alencar de Souza

    2015-01-01

    Full Text Available The sterile insect technique (SIT is widely utilized in the biological control of fruit flies of the family Tephritidae, particularly against the Mediterranean fruit fly. This study investigated the interaction between mating success and morphometric variation in the wings and the production of acoustic signals among three male groups of Ceratitis capitata (Wiedemann: (1 wild males, (2 irradiated with Co-60 (steriles, and (3 irradiated (steriles and treated with ginger oil. The canonical variate analysis discriminated two groups (males irradiated and males wild, based on the morphological shape of the wings. Among males that emit buzz signals, wild males obtained copulation more frequently than males in Groups 2 and 3. The individuals of Group 3 achieved more matings than those in Group 2. Wild males displayed lower pulse duration, higher intervals between pulses, and higher dominant frequency. Regarding the reproductive success, the morphological differences in the wings’ shape between accepted and nonaccepted males are higher in wild males than in the irradiated ones. The present results can be useful in programs using the sterile insect technique for biological control of C. capitata.

  5. Cosmology based on f(R) gravity with O(1) eV sterile neutrino

    Energy Technology Data Exchange (ETDEWEB)

    Chudaykin, Anton S.; Gorbunov, Dmitry S. [Institute for Nuclear Research of the Russian Academy of Sciences, 60th October Anniversary prospect 7a, Moscow 117312 (Russian Federation); Starobinsky, Alexei A. [L.D. Landau Institute for Theoretical Physics of the Russian Academy of Sciences, Moscow 119334 (Russian Federation); Burenin, Rodion A., E-mail: chudy@ms2.inr.ac.ru, E-mail: gorby@ms2.inr.ac.ru, E-mail: alstar@landau.ac.ru, E-mail: rodion@hea.iki.rssi.ru [Space Research Institute of the Russian Academy of Sciences (IKI), Moscow, ul. Profsoyuznaya, 84/32, 117997 (Russian Federation)

    2015-05-01

    We address the cosmological role of an additional O(1) eV sterile neutrino in modified gravity models. We confront the present cosmological data with predictions of the FLRW cosmological model based on a variant of f(R) modified gravity proposed by one of the authors previously. This viable cosmological model which deviation from general relativity with a cosmological constant Λ decreases as R{sup −2n} for large, but not too large values of the Ricci scalar R (while no Λ is introduced by hand at small R) provides an alternative explanation of present dark energy and the accelerated expansion of the Universe (the case n=2 is considered in the paper). Various up-to-date cosmological data sets exploited include measurements of the cosmic microwave background (CMB) anisotropy, the CMB lensing potential, the baryon acoustic oscillations (BAO), the cluster mass function and the Hubble constant. We find that the CMB+BAO constraints strongly restrict the sum of neutrino masses from above. This excludes values of the model parameter λ∼ 1 for which distinctive cosmological features of the model are mostly pronounced as compared to the ΛCDM model, since then free streaming damping of perturbations due to neutrino rest masses is not sufficient to compensate their extra growth occurring in f(R) modified gravity. Thus, in the gravity sector we obtain λ>8.2 (2σ) with the account of systematic uncertainties in galaxy cluster mass function measurements and λ>9.4 (2σ) without them. At the same time in the latter case we find for the sterile neutrino mass 0.47 eV < m{sub ν, sterile} < 1 eV (2σ) assuming that the sterile neutrinos are thermalized and the active neutrinos are massless, not significantly larger than in the standard ΛCDM with the same data set: 0.45 eV < m{sub ν, sterile} < 0.92 eV (2σ). However, a possible discovery of a sterile neutrino with the mass m{sub ν, sterile} ≈ 1.5 eV motivated by various anomalies in neutrino oscillation

  6. Cross-Mating Compatibility and Competitiveness among Aedes albopictus Strains from Distinct Geographic Origins - Implications for Future Application of SIT Programs in the South West Indian Ocean Islands.

    Directory of Open Access Journals (Sweden)

    David Damiens

    Full Text Available The production of large numbers of males needed for a sustainable sterile insect technique (SIT control program requires significant developmental and operational costs. This may constitute a significant economic barrier to the installation of large scale rearing facilities in countries that are undergoing a transition from being largely dependent on insecticide use to be in a position to integrate the SIT against Aedes albopictus. Alternative options available for those countries could be to rely on outsourcing of sterile males from a foreign supplier, or for one centralised facility to produce mosquitoes for several countries, thus increasing the efficiency of the mass-rearing effort. However, demonstration of strain compatibility is a prerequisite for the export of mosquitoes for transborder SIT applications. Here, we compared mating compatibility among Ae. albopictus populations originating from three islands of the South Western Indian Ocean, and assessed both insemination rates and egg fertility in all possible cross-mating combinations. Furthermore, competitiveness between irradiated and non-irradiated males from the three studied strains, and the subsequent effect on female fertility were also examined. Although morphometric analysis of wing shapes suggested phenoptypic differences between Ae. albopictus strains, perfect reproductive compatibility between them was observed. Furthermore, irradiated males from the different islands demonstrated similar levels of competitiveness and induced sterility when confronted with fertile males from any of the other island populations tested. In conclusion, despite the evidence of inter-strain differences based on male wing morphology, collectively, our results provide a new set of expectations for the use of a single candidate strain of mass-reared sterile males for area-wide scale application of SIT against Ae. albopictus populations in different islands across the South Western Indian Ocean. Cross

  7. Parametrization of Seesaw Models and Light Sterile Neutrinos

    CERN Document Server

    Blennow, Mattias

    2011-01-01

    The recent recomputation of the neutrino fluxes from nuclear reactors relaxes the tension between the LSND and MiniBooNE anomalies and disappearance data when interpreted in terms of sterile neutrino oscillations. The simplest extension of the Standard Model with such fermion singlets is the addition of right-handed sterile neutrinos with small Majorana masses. Even when introducing three right-handed neutrinos, this scenario has less free parameters than the 3+2 scenarios studied in the literature. This begs the question whether the best fit regions obtained can be reproduced by this simplest extension of the Standard Model. In order to address this question, we devise an exact parametrization of Standard Model extensions with right-handed neutrinos. Apart from the usual 3x3 neutrino mixing matrix and the 3 masses of the lightest neutrinos, the extra degrees of freedom are encoded in another 3x3 unitary matrix and 3 additional mixing angles. The parametrization includes all the correlations among masses and ...

  8. Search for sterile neutrinos at a new short-baseline CERN neutrino beam

    International Nuclear Information System (INIS)

    Mauri, N.

    2014-01-01

    In the last few years the experimental results on neutrino/anti-neutrino oscillations at Short-Baseline (SBL) showed a tension with several phenomenological models. The recent and carefully recomputed anti-neutrino fluxes from nuclear reactors have further increased this tension drawing a picture not fully compatible with the 3 neutrino oscillation scenario. A sterile neutrino is a neutral lepton which does not couple with W/Z bosons. it is not an exotic particle, its existence being a natural consequence of neutrinos having a non-zero mass. Sterile neutrinos can mix with the active ones through additional mass eigenstates, with no necessary mass scale. We will present an experimental search for sterile neutrinos with a new CERN-SPS neutrino beam using muon spectrometers and large LAr detectors. To definitely clarify the physics issue, the proposed experiment will study oscillations in a muon neutrino / antineutrino beam both in appearance and disappearance modes, exploring the Δm 2 ∼ 1 eV 2 range

  9. Intra-tree activity of male Mediterranean fruit flies (Diptera:Tephritidae): effects of posteclosion light, crowding, adult diet, and irradiation

    International Nuclear Information System (INIS)

    Vargas, R.I.; Prokopy, R.; Hsu, C.L.; Kanehisa, D.

    1998-01-01

    Laboratory-reared Mediterranean fruit flies Ceratitis capitata (Wiedemann) were held under varying conditions of fight, density, food, and irradiation prior to release of males on potted guava, Psidium guajava L., plants in outdoor cages. Male activity after release was measured in terms of number of leaves visited and duration of flights within the plant canopy

  10. Viruses of insects reared for food and feed

    NARCIS (Netherlands)

    Maciel-Vergara, Gabriela; Ros, Vera I.D.

    2017-01-01

    The use of insects as food for humans or as feed for animals is an alternative for the increasing high demand for meat and has various environmental and social advantages over the traditional intensive production of livestock. Mass rearing of insects, under insect farming conditions or even in

  11. Gamma-sterilization

    International Nuclear Information System (INIS)

    Lindgren, E.

    1974-01-01

    The author makes a survey of his experience in sterilization and sterility control of medical products. At present three different methods are used, steamsterilization, gassterilizing and gammasterilizing. The investments and costs for gamma radiation is presented and a comparison of the costs for gamma- and gassterilization including sterility control is made. (M.S.)

  12. Unveiling secret interactions among sterile neutrinos with big-bang nucleosynthesis

    Science.gov (United States)

    Saviano, Ninetta; Pisanti, Ofelia; Mangano, Gianpiero; Mirizzi, Alessandro

    2014-12-01

    Short-baseline neutrino anomalies suggest the existence of low-mass [m ˜O (1 ) eV ] sterile neutrinos νs. These would be efficiently produced in the early universe by oscillations with active neutrino species, leading to a thermal population of the sterile states seemingly incompatible with cosmological observations. In order to relieve this tension it has been recently speculated that new "secret" interactions among sterile neutrinos, mediated by a massive gauge boson X (with MX≪MW), can inhibit or suppress the sterile neutrino thermalization, due to the production of a large matter potential term. We note however, that they also generate strong collisional terms in the sterile neutrino sector that induce an efficient sterile neutrino production after a resonance in matter is encountered, increasing their contribution to the number of relativistic particle species Neff. Moreover, for values of the parameters of the νs-νs interaction for which the resonance takes place at temperature T ≲few MeV , significant distortions are produced in the electron (anti)neutrino spectra, altering the abundance of light element in big bang nucleosynthesis (BBN). Using the present determination of 4He and deuterium primordial abundances we determine the BBN constraints on the model parameters. We find that 2H/H density ratio exclude much of the parameter space if one assumes a baryon density at the best fit value of Planck experiment, ΩBh2=0.02207 , while bounds become weaker for a higher ΩBh2=0.02261 , the 95% C.L. upper bound of Planck. Due to the large error on its experimental determination, the helium mass fraction Yp gives no significant bounds.

  13. Observations on female sterilization in Chile.

    Science.gov (United States)

    Menanteau-Horta, D

    1982-01-01

    and paramedical health services personnel played a significant role in patients' decision to request sterilization. Few women cited mass media as playing a part. Pomeroy and laparoscopic methods were the most popular methods used in Valdivia, 53.8% of the Santiago women were sterilized by the Pomeroy method and the others by Madlener or other methods. Postoperative results of sterilization are divided into clinical problems, postoperative attitude of spouse, and sexual relations. Results indicate that there are no substantial differences between the contraceptive behavior of Catholics and non-Catholics. There is an apparent need for more family planning education in Chile as is evidenced by complications of contraceptive method use. The postoperative consequences of sterilization suggest the need for research and analysis.

  14. Study of water masses variability in the Mediterranean Sea using in-situ data / NEMO-Med12 model.

    Science.gov (United States)

    Margirier, Félix; Testor, Pierre; Mortier, Laurent; Arsouze, Thomas; Bosse, Anthony; Houpert, Loic; Hayes, Dan

    2016-04-01

    In the past 10 years, numerous observation programs in the Mediterranean deployed autonomous platforms (moorings, argo floats, gliders) and thus considerably increased the number of in-situ observations and the data coverage. In this study, we analyse time series built with profile data on interannual scales. Sorting data in regional boxes, we follow the evolution of different water masses in the basin and generate indexes to characterize their evolution. We then put those indexes in relation with external (atmospheric) forcings and present an intercomparison with the NEMO-Med12 model to estimate both the skill of the model and the relevance of the data-sampling in reproducing the evolution of water masses properties.

  15. Galaxy Formation in Sterile Neutrino Dark Matter Models

    Science.gov (United States)

    Menci, N.; Grazian, A.; Lamastra, A.; Calura, F.; Castellano, M.; Santini, P.

    2018-02-01

    We investigate galaxy formation in models with dark matter (DM) constituted by sterile neutrinos. Given their large parameter space, defined by the combinations of sterile neutrino mass {m}ν and mixing parameter {\\sin }2(2θ ) with active neutrinos, we focus on models with {m}ν =7 {keV}, consistent with the tentative 3.5 keV line detected in several X-ray spectra of clusters and galaxies. We consider (1) two resonant production models with {\\sin }2(2θ )=5 × {10}-11 and {\\sin }2(2θ )=2 × {10}-10, to cover the range of mixing parameters consistent with the 3.5 keV line; (2) two scalar-decay models, representative of the two possible cases characterizing such a scenario: a freeze-in and a freeze-out case. We also consider thermal warm DM with particle mass {m}X=3 {keV}. Using a semianalytic model, we compare the predictions for the different DM scenarios with a wide set of observables. We find that comparing the predicted evolution of the stellar mass function, the abundance of satellites of Milky Way–like galaxies, and the global star formation history of galaxies with observations does not allow us to disentangle the effects of the baryonic physics from those related to the different DM models. On the other hand, the distribution of the stellar-to-halo mass ratios, the abundance of faint galaxies in the UV luminosity function at z≳ 6, and the specific star formation and age distribution of local, low-mass galaxies constitute potential probes for the DM scenarios considered. We discuss how future observations with upcoming facilities will enable us to rule out or to strongly support DM models based on sterile neutrinos.

  16. Ozone and carbon monoxide budgets over the Eastern Mediterranean.

    Science.gov (United States)

    Myriokefalitakis, S; Daskalakis, N; Fanourgakis, G S; Voulgarakis, A; Krol, M C; Aan de Brugh, J M J; Kanakidou, M

    2016-09-01

    The importance of the long-range transport (LRT) on O3 and CO budgets over the Eastern Mediterranean has been investigated using the state-of-the-art 3-dimensional global chemistry-transport model TM4-ECPL. A 3-D budget analysis has been performed separating the Eastern from the Western basins and the boundary layer (BL) from the free troposphere (FT). The FT of the Eastern Mediterranean is shown to be a strong receptor of polluted air masses from the Western Mediterranean, and the most important source of polluted air masses for the Eastern Mediterranean BL, with about 40% of O3 and of CO in the BL to be transported from the FT aloft. Regional anthropogenic sources are found to have relatively small impact on regional air quality in the area, contributing by about 8% and 18% to surface levels of O3 and CO, respectively. Projections using anthropogenic emissions for the year 2050 but neglecting climate change calculate a surface O3 decrease of about 11% together with a surface CO increase of roughly 10% in the Eastern Mediterranean. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Investigation of radiation gamma-sterilization effect on sodium alginate hydrogels

    International Nuclear Information System (INIS)

    Valueva, M.I.; Oltarzhevskaya, N.D.; Maksimova, Yu.S.; Fenin, A.A.

    2012-01-01

    The effect of gamma-radiation in doses ensuring materials sterility (6-15 kGy) on alginate hydrogels is studied. For conservation of polymer solutions viscosity after sterilization it is necessary to introduce in polymer matrix different additives inhibiting the radiolysis process. Substances-antioxidants (aqueous extracts of sea-buckthorn and blueberry), polyvinylpyrrolidone, pectin, polyethylene oxides with molecular mass from 400 to 40000 have been studied as the additives. The additives selected have the positive effect on the result of alginate hydrogels sterilization. It is established, that the problem of human tissue radiation protection is closely connected with the problem of biopolymer hydrogels radiation protection [ru

  18. Reduced rearing density increases postrelease migration success of Atlantic salmon (Salmo salar) smolts

    DEFF Research Database (Denmark)

    Larsen, Martin Hage; Johnsson, Jörgen I; Näslund, Joacim

    2016-01-01

    during rearing in the hatchery. However, individuals reared at reduced density had less eroded dorsal fins and opercula relative to those from the high-density treatment. In the stream, the downstream migration success was 16% higher for fish reared at reduced density than for conspecifics kept at high-density......The overall aim of this study was to investigate the effect of rearing density on the post-release survival of Atlantic salmon (Salmo salar) smolts during seaward migration. Fish were either reared at conventional hatchery density or at one-third of conventional density. Three hundred one-year old...... smolts from each density treatment were individually tagged with passive integrated transponder (PIT) tags and released 3.2 km upstream of a stationary antenna array in a natural stream. There were no significant differences in length, body mass, or condition between fish from the two density treatments...

  19. Electric dipole moments of charged leptons with sterile fermions

    International Nuclear Information System (INIS)

    Abada, Asmaa; Toma, Takashi

    2016-01-01

    We address the impact of sterile fermions on charged lepton electric dipole moments. Any experimental signal of these observables calls for scenarios of physics beyond the Standard Model providing new sources of CP violation. In this work, we consider a minimal extension of the Standard Model via the addition of sterile fermions which mix with active neutrinos and we derive the corresponding analytical expressions for the electric dipole moments of charged leptons at two-loop order. Our study reveals that, in order to have a non-vanishing contribution in this framework, the minimal extension necessitates the addition of at least 2 sterile fermion states to the Standard Model field content. Our conclusion is that sterile neutrinos can give significant contributions to the charged lepton electric dipole moments, some of them lying within present and future experimental sensitivity if the masses of the non-degenerate sterile states are both above the electroweak scale. The Majorana nature of neutrinos is also important in order to allow for significative contributions to the charged lepton electric dipole moments. In our analysis we impose all available experimental and observational constraints on sterile neutrinos and we further discuss the prospect of probing this scenario at low and high energy experiments.

  20. Electric dipole moments of charged leptons with sterile fermions

    Energy Technology Data Exchange (ETDEWEB)

    Abada, Asmaa; Toma, Takashi [Laboratoire de Physique Théorique, CNRS, University Paris-Sud, Université Paris-Saclay, 91405 Orsay (France)

    2016-02-26

    We address the impact of sterile fermions on charged lepton electric dipole moments. Any experimental signal of these observables calls for scenarios of physics beyond the Standard Model providing new sources of CP violation. In this work, we consider a minimal extension of the Standard Model via the addition of sterile fermions which mix with active neutrinos and we derive the corresponding analytical expressions for the electric dipole moments of charged leptons at two-loop order. Our study reveals that, in order to have a non-vanishing contribution in this framework, the minimal extension necessitates the addition of at least 2 sterile fermion states to the Standard Model field content. Our conclusion is that sterile neutrinos can give significant contributions to the charged lepton electric dipole moments, some of them lying within present and future experimental sensitivity if the masses of the non-degenerate sterile states are both above the electroweak scale. The Majorana nature of neutrinos is also important in order to allow for significative contributions to the charged lepton electric dipole moments. In our analysis we impose all available experimental and observational constraints on sterile neutrinos and we further discuss the prospect of probing this scenario at low and high energy experiments.

  1. Search for Sterile Neutrinos with the MINOS Long-Baseline Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Timmons, Ashley Michael [Univ. of Manchester (United Kingdom)

    2016-01-01

    This thesis will present a search for sterile neutrinos using data taken with the MINOS experiment between 2005 and 2012. MINOS is a two-detector on-axis experiment based at Fermilab. The NuMI neutrino beam encounters the MINOS Near Detector 1km downstream of the neutrino-production target before traveling a further 734km through the Earth's crust, to reach the Far Detector located at the Soudan Underground Laboratory in Northern Minnesota. By searching for oscillations driven by a large mass splitting, MINOS is sensitive to the existence of sterile neutrinos through looking for any energy-dependent perturbations using a charged-current sample, as well as looking at any relative deficit in neutral current events between the Far and Near Detectors. This thesis will discuss the novel analysis that enabled a search for sterile neutrinos covering five orders of magnitude in the mass splitting and setting a limit in previously unexplored regions of the parameter space $\\left\\{\\Delta m^{2}_{41},\\sin^2\\theta_{24}\\right\\}$, where a 3+1-flavour phenomenological model was used to extract parameter limits. The results presented in this thesis are sensitive to the sterile neutrino parameter space suggested by the LSND and MiniBooNE experiments.

  2. ISO radiation sterilization standards

    International Nuclear Information System (INIS)

    Lambert, Byron J.; Hansen, Joyce M.

    1998-01-01

    This presentation provides an overview of the current status of the ISO radiation sterilization standards. The ISO standards are voluntary standards which detail both the validation and routine control of the sterilization process. ISO 11137 was approved in 1994 and published in 1995. When reviewing the standard you will note that less than 20% of the standard is devoted to requirements and the remainder is guidance on how to comply with the requirements. Future standards developments in radiation sterilization are being focused on providing additional guidance. The guidance that is currently provided in informative annexes of ISO 11137 includes: device/packaging materials, dose setting methods, and dosimeters and dose measurement, currently, there are four Technical Reports being developed to provide additional guidance: 1. AAMI Draft TIR, 'Radiation Sterilization Material Qualification' 2. ISO TR 13409-1996, 'Sterilization of health care products - Radiation sterilization - Substantiation of 25 kGy as a sterilization dose for small or infrequent production batches' 3. ISO Draft TR, 'Sterilization of health care products - Radiation sterilization Selection of a sterilization dose for a single production batch' 4. ISO Draft TR, 'Sterilization of health care products - Radiation sterilization-Product Families, Plans for Sampling and Frequency of Dose Audits'

  3. Neutrino masses in the minimal gauged (B -L ) supersymmetry

    Science.gov (United States)

    Yan, Yu-Li; Feng, Tai-Fu; Yang, Jin-Lei; Zhang, Hai-Bin; Zhao, Shu-Min; Zhu, Rong-Fei

    2018-03-01

    We present the radiative corrections to neutrino masses in a minimal supersymmetric extension of the standard model with local U (1 )B -L symmetry. At tree level, three tiny active neutrinos and two nearly massless sterile neutrinos can be obtained through the seesaw mechanism. Considering the one-loop corrections to the neutrino masses, the numerical results indicate that two sterile neutrinos obtain KeV masses and the small active-sterile neutrino mixing angles. The lighter sterile neutrino is a very interesting dark matter candidate in cosmology. Meanwhile, the active neutrinos mixing angles and mass squared differences agree with present experimental data.

  4. A White Paper on keV sterile neutrino Dark Matter

    Energy Technology Data Exchange (ETDEWEB)

    Adhikari, R. [Centre for Theoretical Physics, Jamia Millia Islamia (Central University), New Delhi-110025 (India); Agostini, M. [Gran Sasso Science Institute (INFN), L' Aquila (Italy); Ky, N. Anh [Institute of physics, Vietnam academy of science and technology, 10 Dao Tan, Ba Dinh, Hanoi (Viet Nam); Araki, T. [Department of physics, Saitama University, Shimo-Okubo 255, 338-8570 Saitama Sakura-ku (Japan); Archidiacono, M. [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark); Bahr, M. [University of California, Santa Barbara (United States); Baur, J. [Commissariat à l' énergie atomique et aux énergies alternatives, Centre de Saclay, DSM/IRFU, 91191 Gif-sur-Yvette (France); Behrens, J. [Westfälische Wilhelms Universität Münster, Institut für Kernphysik, Wilhelm Klemm-Str.9, D-48149 Münster (Germany); Bezrukov, F. [University of Connecticut (United States); Dev, P.S. Bhupal [Consortium for Fundamental Physics, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Borah, D. [Department of Physics, Indian Institute of Technology Guwahati, Assam-781039 (India); Boyarsky, A. [Universiteit Leiden - Instituut Lorentz for Theoretical Physics, P.O. Box 9506, NL-2300 RA Leiden, Netherlands (Netherlands); De Gouvea, A. [Northwestern University (United States); Pires, C.A. de S. [Departamento de Física, UFPB, Caixa Postal 5008, 58051-970, João Pessoa, PB (Brazil); De Vega, H.J. [CNRS LPTHE UPMC Univ P. et M. Curie Paris VI (France); and others

    2017-01-01

    We present a comprehensive review of keV-scale sterile neutrino Dark Matter, collecting views and insights from all disciplines involved—cosmology, astrophysics, nuclear, and particle physics—in each case viewed from both theoretical and experimental/observational perspectives. After reviewing the role of active neutrinos in particle physics, astrophysics, and cosmology, we focus on sterile neutrinos in the context of the Dark Matter puzzle. Here, we first review the physics motivation for sterile neutrino Dark Matter, based on challenges and tensions in purely cold Dark Matter scenarios. We then round out the discussion by critically summarizing all known constraints on sterile neutrino Dark Matter arising from astrophysical observations, laboratory experiments, and theoretical considerations. In this context, we provide a balanced discourse on the possibly positive signal from X-ray observations. Another focus of the paper concerns the construction of particle physics models, aiming to explain how sterile neutrinos of keV-scale masses could arise in concrete settings beyond the Standard Model of elementary particle physics. The paper ends with an extensive review of current and future astrophysical and laboratory searches, highlighting new ideas and their experimental challenges, as well as future perspectives for the discovery of sterile neutrinos.

  5. A search for sterile neutrinos with the latest cosmological observations

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Lu; Zhang, Jing-Fei [Northeastern University, Department of Physics, College of Sciences, Shenyang (China); Zhang, Xin [Northeastern University, Department of Physics, College of Sciences, Shenyang (China); Peking University, Center for High Energy Physics, Beijing (China)

    2017-06-15

    We report the result of a search for sterile neutrinos with the latest cosmological observations. Both cases of massless and massive sterile neutrinos are considered in the ΛCDM cosmology. The cosmological observations used in this work include the Planck 2015 temperature and polarization data, the baryon acoustic oscillation data, the Hubble constant direct measurement data, the Planck Sunyaev-Zeldovich cluster counts data, the Planck lensing data, and the cosmic shear data. We find that the current observational data give a hint of the existence of massless sterile neutrino (as dark radiation) at the 1.44σ level, and the consideration of an extra massless sterile neutrino can indeed relieve the tension between observations and improve the cosmological fit. For the case of massive sterile neutrino, the observations give a rather tight upper limit on the mass, which implies that actually a massless sterile neutrino is more favored. Our result is consistent with the recent result of neutrino oscillation experiment done by the Daya Bay and MINOS collaborations, as well as the recent result of cosmic ray experiment done by the IceCube collaboration. (orig.)

  6. Genetic sexing of the Mediterranean fruit fly

    International Nuclear Information System (INIS)

    1990-01-01

    In the early 1980s, it was recognized by the FAO and the IAEA that a genetic sexing method for the Mediterranean fruit fly (medfly) would greatly improve the efficacy of the medfly sterile insect technique (SIT) and reduce its costs. These Proceedings summarize the research and development findings of the Agency's co-operators in the co-ordinated research programme to develop a genetic sexing method for the medfly. Great progress has been made in many aspects of medfly genetics. including the development of a number of genetic sexing strains. Contents: Genetics, Cytogenetics and Population Genetics. Genetic Sexing of Ceratitis Capitata by Morphological, Biochemical and other means. Recommendations. Refs, figs and tabs

  7. New method for rearing Spodoptera frugiperda in laboratory shows that larval cannibalism is not obligatory

    Directory of Open Access Journals (Sweden)

    Cherre Sade Bezerra Da Silva

    2013-09-01

    Full Text Available New method for rearing Spodoptera frugiperda in laboratory shows that larval cannibalism is not obligatory. Here we show, for the first time, that larvae of the fall armyworm (FAW, Spodoptera frugiperda (Lepidoptera, Noctuidae, can be successfully reared in a cohort-based manner with virtually no cannibalism. FAW larvae were reared since the second instar to pupation in rectangular plastic containers containing 40 individuals with a surprisingly ca. 90% larval survivorship. Adult females from the cohort-based method showed fecundity similar to that already reported on literature for larvae reared individually, and fertility higher than 99%, with the advantage of combining economy of time, space and material resources. These findings suggest that the factors affecting cannibalism of FAW larvae in laboratory rearings need to be reevaluated, whilst the new technique also show potential to increase the efficiency of both small and mass FAW rearings.

  8. Sexual Competitiveness, Field Survival, and Dispersal of Anastrepha obliqua (Diptera: Tephritidae) Fruit Flies Irradiated at Different Doses.

    Science.gov (United States)

    Gallardo-Ortiz, Uriel; Pérez-Staples, Diana; Liedo, Pablo; Toledo, Jorge

    2018-04-02

    The sterile insect technique (SIT) is used in area-wide pest management programs for establishing low pest prevalence and/or areas free of fruit flies (Diptera: Tephritidae). The aim of this technique is to induce high levels of sterility in the wild population, for this the released insects must have a high sexual competitiveness and field dispersal. However, radiation decreases these biological attributes that do not allow it to compete successfully with wild insects. In this study the sexual competitiveness, field survival and dispersal of Anastrepha obliqua (Macquart; Diptera: Tephritidae) irradiated at 0, 40, 50, 60, 70, and 80 Gy were evaluated in laboratory. A dose of 60 Gy produced 98% sterility, whereas doses of 70 and 80 Gy produced 99% sterility. Sexual competitiveness was assessed in field cages, comparing males irradiated at 0, 50, 60, 70, and 80 Gy against wild males for mating with wild fertile females. Males irradiated at 50 and 60 Gy achieved more matings than those irradiated at 70 and 80 Gy. Wild males were more competitive than mass-reared males, even when these were not irradiated (0 Gy). There was no effect of irradiation on mating latency, yet wild males showed significantly shorter mating latency than mass-reared males. Female remating did not differ among those that mated with wild males and those that mated with males irradiated with different doses. The relative sterility index (RSI) increased from 0.25 at 80 Gy to 0.37 at 60 Gy. The Fried competitiveness index was 0.69 for males irradiated at 70 Gy and 0.57 for those irradiated at 80 Gy, which indicates that a 10 Gy reduction in the irradiation dose produces greater induction of sterility in the wild population. There were no significant differences in field survival and dispersal between flies irradiated at 70 or 80 Gy. Reducing the irradiation dose to 60 or 70 Gy could improve the performance of sterile males and the effectiveness of the SIT. Our results also distinguish between the

  9. Effect of fermentation and sterilization on anthocyanins in blueberry.

    Science.gov (United States)

    Nie, Qixing; Feng, Lei; Hu, Jielun; Wang, Sunan; Chen, Haihong; Huang, Xiaojun; Nie, Shaoping; Xiong, Tao; Xie, Mingyong

    2017-03-01

    Blueberry products have various health benefits due to their high content of dietary anthocyanins. The aim of this study was to investigate the impact of fermentation and sterilization on total anthocyanin content, composition and some quality attributes of blueberry puree. The blueberry puree used here was fermented for 40 h at 37 °C by Lactobacillus after sterilization. The method of ultra-performance liquid chromatography-mass spectrometry was optimized for the rapid analysis of anthocyanins. Quality attributes including pH, color, total soluble solids and viscosity were measured. A total of 21 anthocyanins and five anthocyanidins were quantified by ultra-performance liquid chromatography. Fermented blueberry had reduced total anthocyanin content (29%) and levels of individual anthocyanins compared with fresh blueberry. Total anthocyanin content was decreased 46% by sterilization, and different degradation behavior of individual anthocyanin was appeared between fermented and sterilized-fermented blueberry puree. Fermentation and sterilization decreased the total soluble solids and pH and changed color parameters, while minimally influencing viscosity. The loss of total anthocyanin content by fermentation was related to the unstable structure of blueberry anthocyanins. Anthocyanins are sensitive to temperature (>80 °C), and degradation of anthocyanins by sterilization in blueberry should be considered in the fermentation procedure. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  10. Sexual Competitiveness of Anastrepha ludens (Diptera: Tephritidae) Males Exposed to Citrus aurantium and Citrus paradisi Essential Oils.

    Science.gov (United States)

    Morató, Santiago; Shelly, Todd; Rull, Juan; Aluja, Martin

    2015-04-01

    Males of the Mediterranean fruit fly (Ceratitis capitata (Wiedemann)) display increased mating competitiveness following exposure to the odor of certain host and nonhost plants, and this phenomenon has been used in the sterile insect technique to boost the mating success of released, sterile males. Here, we aimed to establish whether males of the Mexican fruit fly (Anastrepha ludens (Loew)) gain a mating advantage when exposed to the aroma of two preferred hosts, grapefruit (Citrus paradisi Macfadyen) and bitter orange (Citrus aurantium L.). Under seminatural conditions, we observed that, in trials using wildish males (from a young laboratory colony started with wild flies) exclusively, exposure to the aroma of bitter orange had no effect on male mating success but exposure to the odor grapefruit oil increased male mating success significantly. In a separate test involving both exposed and nonexposed wildish and mass-reared, sterile males, although wildish males were clearly more competitive than sterile males, exposure to grapefruit oil had no detectable effect on either male type. Exposure to oils had no effect on copulation duration in any of the experiments. We discuss the possibility that the positive effect of grapefruit essential oils on wildish male competitiveness may have been linked to exposure of females to grapefruit as a larval food, which may have imprinted them with grapefruit odors during pupal eclosion and biased their response as adults to odors of their maternal host. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Search for sterile neutrinos with IceCube DeepCore

    Energy Technology Data Exchange (ETDEWEB)

    Terliuk, Andrii [DESY, Platanenallee 6, 15738 Zeuthen (Germany); Collaboration: IceCube-Collaboration

    2016-07-01

    The DeepCore detector is a sub-array of the IceCube Neutrino Observatory that lowers the energy threshold for neutrino detection down to approximately 10 GeV. DeepCore is used for a variety of studies including atmospheric neutrino oscillations. The standard three-neutrino oscillation paradigm is tested using the DeepCore detector by searching for an additional light, sterile neutrino with a mass on the order of 1 eV. Sterile neutrinos do not interact with the ordinary matter, however they can be mixed with the three active neutrino states. Such mixture changes the picture of standard neutrino oscillations for atmospheric neutrinos with energies below 100 GeV. The capabilities of DeepCore detector to measure such sterile neutrino mixing will be presented in this talk.

  12. Development of quality control procedures for mass produced and released oriental fruit flies, Bactrocera philippinensis for SIT programmes

    International Nuclear Information System (INIS)

    Resilva, Sotero S.; Obra, Glenda B.

    2001-01-01

    This report summarizes different quality control tests necessary to monitor the behavior of oriental fruit fly, B. philippinensis from the mass rearing facility to the release site. Results of routine quality control tests revealed that pupal size, emergence, fliers, sex ration, stress tests, mating index and fertility tests were all above satisfactory levels in pre-and post-irradiation treatment. Tests at the release site showed similar findings except for mating index where poor performance of flies were observed. Fertility and fecundity tests indicate that complete sterility of OFF was achieved at dose ranging from 68-104 Gy. Standard specifications required for weekly and monthly quality control tests was not yet established because release of sterile flies in Guimaras started only last April, 2001. In determining eye color changes in relation to physiological development, eye appearance of the pupae is dark yellowish brown (HUE 10 YR 3/6) at 7 days old where irradiation is to be applied for sterilization. Cross correlation of results showed large pupae had great advantage over medium and small pupae in terms of flight dispersal. Poor emergence and fliers of small pupae were observed when irradiated and chilled for 24 hours. However, no significant difference was observed on mating preference, longevity and fertility among the three pupal size groups. (Author)

  13. Energy analysis in sterilization process of food

    International Nuclear Information System (INIS)

    Lee, Dong Sun; Pyun, Yu Ryang

    1986-01-01

    A procedure was developed for predicting energy consumption of batch type thermal processing of food. From mass and energy balance equations various energy usages or losses were estimated for steam sterilization of model food system in No.301-7 can (Φ74.1 x 113.0mm) at three different temperatures. Selected models were 5 % bentonite solution for conductive food and tap water for convective food. Total steam or energy consumption was higher at 110 deg C than at two other higher temperatures (121 deg C and 130 deg C). High energy consumption at low sterilization temperature was mainly due to high bleeding steam energy and convective and radiative heat losses. Thermal energy efficiency was also disscussed. (Author)

  14. Improved determination of sterile neutrino dark matter spectrum

    International Nuclear Information System (INIS)

    Ghiglieri, J.; Laine, M.

    2015-01-01

    The putative recent indication of an unidentified 3.55 keV X-ray line in certain astrophysical sources is taken as a motivation for an improved theoretical computation of the cosmological abundance of 7.1 keV sterile neutrinos. If the line is interpreted as resulting from the decay of Warm Dark Matter, the mass and mixing angle of the sterile neutrino are known. Our computation then permits for a determination of the lepton asymmetry that is needed for producing the correct abundance via the Shi-Fuller mechanism, as well as for an estimate of the non-equilibrium spectrum of the sterile neutrinos. The latter plays a role in structure formation simulations. Results are presented for different flavour structures of the neutrino Yukawa couplings and for different types of pre-existing lepton asymmetries, accounting properly for the charge neutrality of the plasma and incorporating approximately hadronic contributions.

  15. Equilibrium of vegetation and climate at the European rear edge. A reference for climate change planning in mountainous Mediterranean regions.

    Science.gov (United States)

    Ruiz-Labourdette, Diego; Martínez, Felipe; Martín-López, Berta; Montes, Carlos; Pineda, Francisco D

    2011-05-01

    Mediterranean mountains harbour some of Europe's highest floristic richness. This is accounted for largely by the mesoclimatic variety in these areas, along with the co-occurrence of a small area of Eurosiberian, Boreal and Mediterranean species, and those of Tertiary Subtropical origin. Throughout the twenty-first century, we are likely to witness a climate change-related modification of the biogeographic scenario in these mountains, and there is therefore a need for accurate climate regionalisations to serve as a reference of the abundance and distribution of species and communities, particularly those of a relictic nature. This paper presents an objective mapping method focussing on climate regions in a mountain range. The procedure was tested in the Cordillera Central Mountains of the Iberian Peninsula, in the western Mediterranean, one of the ranges occupying the largest area of the Mediterranean Basin. This regionalisation is based upon multivariate analyses and upon detailed cartography employing 27 climatic variables. We used spatial interpolation of data based on geographic information. We detected high climatic diversity in the mountain range studied. We identified 13 climatic regions, all of which form a varying mosaic throughout the annual temperature and rainfall cycle. This heterogeneity results from two geographically opposed gradients. The first one is the Mediterranean-Euro-Siberian variation of the mountain range. The second gradient involves the degree of oceanicity, which is negatively related to distance from the Atlantic Ocean. The existing correlation between the climatic regions detected and the flora existing therein enables the results to be situated within the projected trends of global warming, and their biogeographic and ecological consequences to be analysed.

  16. Sterile Neutrino Searches in MINOS and MINOS+ Experiments

    International Nuclear Information System (INIS)

    Huang, Junting

    2015-01-01

    This dissertation presents the searches on sterile neutrinos using the data collected in MINOS+ Experiment from September 2013 to September 2014, and the full data set of MINOS Experiment collected from 2005 to 2012. Anomalies in short baseline experiments, such as LSND and MiniBooNE, showed hints of sterile neutrinos, a type of neutrino that does not interact with the Standard Model particles. In this work, two models are considered: 3+1 and large extra dimension (LED). In the 3+1 model, one sterile neutrino state is added into the standard oscillation scheme consisting of three known active neutrino states v e , v μ and v τ . In the LED model, sterile neutrinos arise as Kaluza-Klein (KK) states due to assumed large extra dimensions. Mixing between sterile and active neutrino states may modify the oscillation patterns observed in the MINOS detectors. Both searches yield null results. For 3+1, a combined fit of MINOS and MINOS+ data gives a stronger limit on θ 24 in the range of 10 -2 eV 2 < Δm 43 2 < 1 eV 2 than previous experiments. For LED, with the complete MINOS data set, the size of extra dimensions is constrained to be smaller than ~ 0.35 μm at 90% C.L. in the limit of a vanishing lightest neutrino mass.

  17. THE EFFECTS OF THREE DIFFERENT REAR KNEE ANGLES ON KINEMATICS IN THE SPRINT START

    Directory of Open Access Journals (Sweden)

    C. Milanese

    2014-08-01

    Full Text Available The purpose of this study was to investigate the rear knee angle range in the set position that allows sprinters to reach greater propulsion on the rear block during the sprint start. Eleven university-track team sprinters performed the sprint start using three rear knee angle conditions: 90°, 115° and 135°. A motion capture system consisting of 8 digital cameras (250 Hz was used to record kinematic parameters at the starting block phase and the acceleration phase. The following variables were considered: horizontal velocity of the centre of mass (COM, COM height, block time, pushing time on the rear block, percentage of pushing time on the rear block, force impulse, push-off angle and length of the first two strides. The main results show that first, horizontal block velocity is significantly greater at 90° vs 115° and 135° rear knee angle (p<0.05 and p<0.001 respectively at block clearance and the first two strides; second, during the pushing phase, the percentage of pushing time of the rear leg is significantly greater at 90° vs 135° rear knee angle (p<0.01. No significant difference was found for block time among the conditions. These results indicate that block velocity is the main kinematic parameter affected by rear knee angle during the starting block phase and acceleration phase. Furthermore, the 90° rear knee angle allows for a better push-off of the rear leg than larger angles at the set position. The findings of this study provide some direction and useful practical advice in defining an efficient rear leg biomechanical configuration at the set position.

  18. Differences in behaviour and physiology between adult surrogate-reared and mother-reared Cynomolgous monkeys (Macaca fascicularis)

    NARCIS (Netherlands)

    Luijk, I.A.F. van; Timmermans, P.J.A.; Sweep, C.G.J.; Willems, J.; Vossen, J.M.H.

    2000-01-01

    Previous studies of the effects of rearing conditions on exploratory behaviour revealed that 80% of monkeys reared in peer groups with surrogate mothers developed neophobia, whereas only 15 % of mother-reared monkeys did. Young surrogate-reared and, especially, isolated rhesus monkeys are known to

  19. Coupling active and sterile neutrinos in the cosmon plus seesaw framework

    International Nuclear Information System (INIS)

    Bernardini, A.E.

    2010-01-01

    The cosmological evolution of neutrino energy densities driven by cosmon-type field equations is introduced assuming that active and sterile neutrinos are intrinsically connected by cosmon fields through the seesaw mechanism. Interpreting sterile neutrinos as dark matter adiabatically coupled with dark energy results in a natural decoupling of (active) mass varying neutrino (MaVaN) equations. Identifying the dimensionless scale of the seesaw mechanism, m/M, with a power of the cosmological scale factor, a, allows for embedding the resulting masses into the generalized Chaplygin gas (GCG) scenario for the dark sector. Without additional assumptions, our findings establish a precise connection among three distinct frameworks: the cosmon field dynamics for MaVaN's, the seesaw mechanism for dynamical mass generation and the GCG scenario. Our results also corroborate with previous assertions that mass varying particles can be the right responsible for the stability issue and for the cosmic acceleration of the universe.

  20. Vitality Improvement of the Mediterranean Fruit Fly, Ceratitis capitata Wied 1- Measured by using dehydrogenase Enzyme Activities

    International Nuclear Information System (INIS)

    Salama, M.S.; Shoman, A.A.; Elbermawy, S.M.; Abul Yazid, I.

    2000-01-01

    The present study searches for the improvement vitality of the Mediterranean fruit fly, Ceratitis capitata Wied. Through the induction of a specific variance (mutation) in the genetic material. Several types of treatments that were thought to cause this mutation were used, as IGR's, temperature, formaldehyde, colchicine, alcohols, several types of larval rearing media and gamma-rays. Generally, the activities of the energy enzymes alpha-glycerophosphate dehydrogenase (alpha-GPDH) enzyme lactate dehydrogenase (LDH) enzyme and malate dehydrogenase (MDH) enzyme, when used as a direct measure for the fly vitality, increased due to treatments of the egg stage by the previously mentioned treatments specially by the usage of rice hulls in the larval rearing medium alone or followed by irradiation of the pupal stage with 90 Gy

  1. Radiation sterilization of livestock feeds

    International Nuclear Information System (INIS)

    Kawashima, Koji

    1984-01-01

    The radiation sterilization of livestock feeds is not much used presently because the process is not known well, and the cost is relatively high. However, its effect of sterilization is absolute, the radiation-sterilized feeds are safe in both nutrition and toxicity, and do not affect the appetite of livestocks, and the radiation energy required is small. In the future, as in the sterilization of medical supplies, feed radiation sterilization plants should be established, to stabilize livestock industry and to contribute to the health control of experimental animals. The following matters are described: radiation, comparison between radiation sterilization and other sterilization methods, the practice of feed radiation sterilization, the adverse effects of radiation sterilization, economic aspect, and the situation of feed radiation sterilization in various countries. (Mori, K.)

  2. Inherited sterility in insects

    International Nuclear Information System (INIS)

    Carpenter, J.E.; Marec, F.; Bloem, S.

    2005-01-01

    The unique genetic phenomena responsible for inherited sterility (IS) in Lepidoptera and some other arthropods, as compared with full sterility, provide advantages for pest control. Lepidopteran females are usually more sensitive to radiation than males of the same species. This allows the radiation dose to be adjusted to suit programme requirements. When partially sterile males mate with wild females, the radiation-induced deleterious effects are inherited by the F 1 generation. As a result, egg hatch is reduced and the resulting offspring are both highly sterile and predominately male. Compared with the high radiation required to achieve full sterility in Lepidoptera, the lower dose of radiation used to induce F 1 sterility increases the quality and competitiveness of the released insects as measured by improved dispersal after release, increased mating ability, and superior sperm competition. F 1 sterile progeny produced in the field enhance the efficacy of released partially sterile males, and improve compatibility with other pest control strategies. In addition, F 1 sterile progeny can be used to increase the production of natural enemies, and to study the potential host and geographical ranges of exotic lepidopteran pests. (author)

  3. Effects of vehicle front-end stiffness on rear seat dummies in NCAP and FMVSS208 tests.

    Science.gov (United States)

    Sahraei, Elham; Digges, Kennerly; Marzougui, Dhafer

    2013-01-01

    This study is devoted to quantifying changes in mass and stiffness of vehicles tested by the National Highway Traffic Safety Administration (NHTSA) over the past 3 decades (model years 1982 to 2010) and understanding the effect of those changes on protection of rear seat occupants. A total of 1179 tests were used, and the changes in their mass and stiffness versus their model year was quantified. Additionally, data from 439 dummies tested in rear seats of NHTSA's full frontal crashes were analyzed. Dummies were divided into 3 groups based on their reference injury criteria. Multiple regressions were performed with speed, stiffness, and mass as predicting variables for head, neck, and chest injury criteria. A significant increase in mass and stiffness over model year of vehicles was observed, for passenger cars as well as large platform vehicles. The result showed a significant correlation (P-value < .05) between the increase in stiffness of the vehicles and increase in head and chest injury criteria for all dummy sizes. These results explain that stiffness is a significant contributor to previously reported decreases in protection of rear seat occupants over model years of vehicles.

  4. Search for heavy sterile neutrinos in trileptons at the LHC

    International Nuclear Information System (INIS)

    Dib, Claudio O.; Kim, C.S.; Wang, Kechen; Chinese Academy of Sciences, Beijing

    2017-03-01

    We present a search strategy for both Dirac and Majorana sterile neutrinos from the purely leptonic decays of W"±→e"±e"±μ"-"+ν and μ"±μ"±e"-"+ν at the 14 TeV LHC. The discovery and exclusion limits for sterile neutrinos are shown using both the Cut-and-Count (CC) and Multi-Variate Analysis (MVA) methods. We also discriminate between Dirac and Majorana sterile neutrinos by exploiting a set of kinematic observables which differ between the Dirac and Majorana cases. We find that the MVA method, compared to the more common CC method, can greatly enhance the discovery and discrimination limits. Two benchmark points with sterile neutrino mass m_N=20 GeV and 50 GeV are tested. For an integrated luminosity of 3000 fb"-"1, sterile neutrinos can be found with 5σ significance if heavy-to-light neutrino mixings vertical stroke U_N_e vertical stroke "2∝ vertical stroke U_N_μ vertical stroke "2∝10"-"6, while Majorana vs. Dirac discrimination can be reached if at least one of the mixings is of order 10"-"5.

  5. Dynamical Influence and Operational Impacts of an Extreme Mediterranean Cold Surge

    Science.gov (United States)

    2013-06-01

    in significant flooding over regions surrounding the Mediterranean Sea ( Trigo , Bigg, & Davies 2002). The cold air mass and associated cyclogenesis...119, 17–55. Trigo , I., G. Bigg, and T. Davies, 2002: Climatology of cyclogenesis mechanisms in the Mediterranean. Mon. Wea. Rev., 130, 549–569

  6. Measurement of Leaf Mass and Leaf Area of Oaks In A Mediterranean-climate Region For Biogenic Emission Estimation

    Science.gov (United States)

    Karlik, J.

    Given the key role played by biogenic volatile organic compounds (BVOC) in tro- pospheric chemistry and regional air quality, it is critical to generate accurate BVOC emission inventories. Because several oak species have high BVOC emission rates, and oak trees are often of large stature with corresponding large leaf masses, oaks may be the most important genus of woody plants for BVOC emissions modeling in the natural landscapes of Mediterranean-climate regions. In California, BVOC emis- sions from oaks may mix with anthropogenic emissions from urban areas, leading to elevated levels of ozone. Data for leaf mass and leaf area for a stand of native blue oaks (Quercus douglasii) were obtained through harvest and leaf removal from 14 trees lo- cated in the Sierra Nevada foothills of central California. Trees ranged in height from 4.2 to 9.9 m, with trunk diameters at breast height of 14 to 85 cm. Mean leaf mass density was 730 g m-2 for the trees and had an overall value of 310 g m-2 for the site. Consideration of the surrounding grassland devoid of trees resulted in a value of about 150 g m-2, less than half of reported values for eastern U.S. oak woodlands, but close to a reported value for oaks found in St. Quercio, Italy. The mean value for leaf area index (LAI) for the trees at this site was 4.4 m2 m-2. LAI for the site was 1.8 m2 m-2, but this value was appropriate for the oak grove only; including the surrounding open grassland resulted in an overall LAI value of 0.9 m2 m-2 or less. A volumetric method worked well for estimating the leaf mass of the oak trees. Among allometric relationships investigated, trunk circumference, mean crown radius, and crown projec- tion were well correlated with leaf mass. Estimated emission of isoprene (mg C m-2 h-1) for the site based these leaf mass data and experimentally determined emission rate was similar to that reported for a Mediterranean oak woodland in France.

  7. Hiding an elephant: heavy sterile neutrino with large mixing angle does not contradict cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Bezrukov, F. [The University of Manchester, School of Physics and Astronomy, Oxford Road, Manchester M13 9PL (United Kingdom); Chudaykin, A.; Gorbunov, D., E-mail: Fedor.Bezrukov@manchester.ac.uk, E-mail: chudy@ms2.inr.ac.ru, E-mail: gorby@ms2.inr.ac.ru [Institute for Nuclear Research of the Russian Academy of Sciences, 60th October Anniversary prospect 7a, Moscow 117312 (Russian Federation)

    2017-06-01

    We study a model of a keV-scale sterile neutrino with a relatively large mixing with the Standard Model sector. Usual considerations predict active generation of such particles in the early Universe, which leads to constraints from the total Dark Matter density and absence of X-ray signal from sterile neutrino decay. These bounds together may deem any attempt of creation of the keV scale sterile neutrino in the laboratory unfeasible. We argue that for models with a hidden sector coupled to the sterile neutrino these bounds can be evaded, opening new perspectives for the direct studies at neutrino experiments such as Troitsk ν-mass and KATRIN. We estimate the generation of sterile neutrinos in scenarios with the hidden sector dynamics keeping the sterile neutrinos either massless or superheavy in the early Universe. In both cases the generation by oscillations from active neutrinos in plasma is suppressed.

  8. Evaluation of the effect of horse blood supplemented with human ...

    African Journals Online (AJOL)

    Tsetse flies are large biting insects that belong to the genus Glossina. Both .... and binary data (e.g mortality, pupae classes, etc) and b) one way analysis of variance for ..... Automation of tsetse mass rearing for use in sterile insect technique.

  9. Can sterile neutrinos be ruled out as warm dark matter candidates?

    CERN Document Server

    Viel, M; Hähnelt, M G; Matarrese, S; Riotto, Antonio; Viel, Matteo; Lesgourgues, Julien; Haehnelt, Martin G.; Matarrese, Sabino; Riotto, Antonio

    2006-01-01

    We present constraints on the mass of Warm Dark Matter (WDM) particles from a combined analysis of the matter power spectrum inferred from the SDSS (Sloan Digital Sky Survey) Lyman-alpha flux power spectrum at 2.2 10 keV (2 sigma) if the WDM consists of sterile neutrinos and m_wdm > 2 keV (2 sigma) for early decoupled thermal relics. These results significantly improve our previous estimates based on high-resolution Lyman-alpha forest data at lower redshift. Our new limits are consistent with those of Seljak et al. (2006), albeit ~ 30 % smaller. If we combine this bound with the constraint derived from X-ray flux observations in the Coma cluster periphery (Boyarsky et al.), we find that the only allowed sterile neutrino mass is ~ 10 keV (in the standard production scenario with non-resonant neutrino oscillations). Adding constraints based on X-ray fluxes from the Andromeda galaxy or the Milky Way, we find that dark matter particles cannot be sterile neutrinos, unless the latter are produced by resonant oscill...

  10. The impact of sterile neutrinos on CP measurements at long baselines

    International Nuclear Information System (INIS)

    Gandhi, Raj; Kayser, Boris; Masud, Mehedi; Prakash, Suprabh

    2015-01-01

    With the Deep Underground Neutrino Experiment (DUNE) as an example, we show that the presence of even one sterile neutrino of mass ∼1 eV can significantly impact the measurements of CP violation in long baseline experiments. Using a probability level analysis and neutrino-antineutrino asymmetry calculations, we discuss the large magnitude of these effects, and show how they translate into significant event rate deviations at DUNE. Our results demonstrate that measurements which, when interpreted in the context of the standard three family paradigm, indicate CP conservation at long baselines, may, in fact hide large CP violation if there is a sterile state. Similarly, any data indicating the violation of CP cannot be properly interpreted within the standard paradigm unless the presence of sterile states of mass O(1 eV) can be conclusively ruled out. Our work underscores the need for a parallel and linked short baseline oscillation program and a highly capable near detector for DUNE, in order that its highly anticipated results on CP violation in the lepton sector may be correctly interpreted.

  11. Development Of Biosteres sp Parasitation On Larvae Of Bactrocera carambolae (Drew and Hancock) As Complementary Of Sterile Insect Technique

    International Nuclear Information System (INIS)

    Sikumbang, Darmawi; Nasution, Indah A.; Indarwatmi, M.; Kuswadi, Achmad N.

    2002-01-01

    Sterile insect technique was compatible with biological control after parasitoid releasing. In order to find out suitable life stage of B. carambolae to use as host in the mass rearing of Biosteres sp. parasitoid, an efectivity of the parasitoid infestation on different age of B. carambolae egg by putting fruits in cage containing 200 pairs of B. carambolae flies for the 1 hour. The fruit of infected fruit fly larvae with the different age i.e. 1,2,3, and 4 days were offered to 80 pairs of adult pamsitoid age 1,2, and 3 weeks for old for two hours i.e. 7.00-9.00; 9.00- 11.00; 11.00-13.00; 13.00-15.00; and 15.00-17.00. Numbers of parasitoid emerge from each fruit were observed. Results of the parasitation effectiveness assays show that 1-2 days old larvae were the most severely infested larvae infestation by the done at 7-15 of the day by the day parasitoid. Infestation mostly done by parasitoid of 7-14 days old

  12. Effect of successive irradiated generations on the biological activities of the mediterranean fruit fly, ceratitis capitata (Wled)

    International Nuclear Information System (INIS)

    Shoukry, M.A.; Guneidy, A.M.; Wakid, A.D.; El-Kholy, M.S.

    1995-01-01

    The accumulated effects of irradiated materials in the mediterranean fruit fly (medfly), ceratitis capitata (Wied) offsprings resulted from successively irradiated generations of eggs, pupae or adults were evaluated . Results showed that successive irradiation affected only the biological parameters that concern with the genetic cells i.e. sterility and fecundity. On the other hand, parameters concern the somatic cells i.e. Survival, sex-ration and mating activity were not significantly affected

  13. Biological basis of the sterile insect technique

    International Nuclear Information System (INIS)

    Lance, D.R.; McInnis, D.O.

    2005-01-01

    In principle, the sterile insect technique (SIT) is applicable to controlling a wide variety of insect pests, but biological factors, interacting with socio-economic and political forces, restrict its practical use to a narrower set of pest species and situations. This chapter reviews how the biology and ecology of a given pest affect the feasibility and logistics of developing and using the SIT against that pest insect. The subjects of pest abundance, distribution, and population dynamics are discussed in relation to producing and delivering sufficient sterile insects to control target populations. Pest movement and distribution are considered as factors that influence the feasibility and design of SIT projects, including the need for population- or area-wide management approaches. Biological characteristics, that affect the ability of sterile insects to interact with wild populations, are presented, including the nature of mating systems of pests, behavioural and physiological consequences of mass production and sterilization, and mechanisms that males use to block a female's acquisition and/or use of sperm from other males. An adequate knowledge of the biology of the pest species and potential target populations is needed, both for making sound decisions on whether integration of the SIT into an area-wide integrated pest management (AW-IPM) programme is appropriate, and for the efficient and effective application of the technique. (author)

  14. Sterile Neutrino Searches in MINOS and MINOS+ Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Junting [Univ. of Texas, Austin, TX (United States)

    2015-05-01

    This dissertation presents the searches on sterile neutrinos using the data collected in MINOS+ Experiment from September 2013 to September 2014, and the full data set of MINOS Experiment collected from 2005 to 2012. Anomalies in short baseline experiments, such as LSND and MiniBooNE, showed hints of sterile neutrinos, a type of neutrino that does not interact with the Standard Model particles. In this work, two models are considered: 3+1 and large extra dimension (LED). In the 3+1 model, one sterile neutrino state is added into the standard oscillation scheme consisting of three known active neutrino states ve, vμ and vτ. In the LED model, sterile neutrinos arise as Kaluza-Klein (KK) states due to assumed large extra dimensions. Mixing between sterile and active neutrino states may modify the oscillation patterns observed in the MINOS detectors. Both searches yield null results. For 3+1, a combined fit of MINOS and MINOS+ data gives a stronger limit on θ24 in the range of 10-2 eV2 < Δm412 < 1 eV2 than previous experiments. For LED, with the complete MINOS data set, the size of extra dimensions is constrained to be smaller than ~ 0.35 μm at 90% C.L. in the limit of a vanishing lightest neutrino mass.

  15. [Sterilization and eugenics].

    Science.gov (United States)

    Shasha, Shaul M

    2011-04-01

    The term "eugenics" was coined by Francis Galton in 1883 and was defined as the science of the improvement of the human race by better breeding. "Positive eugenics" referred to methods of encouraging the "most fit" to reproduce more often, while "negative eugenics" was related to ways of discouraging or preventing the "less fit" from reproducing by birth control and sterilization. Many western countries adopted eugenics programs including Britain, Canada, Norway, Australia, Switzerland and others. In Sweden more then 62,000 "unfits" were forcibly sterilized. Many states in the U.S.A. had adopted marriage laws with eugenics criteria including forced sterilization. Approximately 64,000 individuals were sterilized. Eugenics considerations also lay behind the adoption of the Immigration Restriction Act of 1924. The Largest plan on eugenics was adopted by the Nazi regime in Germany. Hundreds of thousands of people, who were viewed as being "unfit", were forcibly sterilized by different methods: Surgical sterilization or castration with severe complications and high mortality rates. X-ray irradiation. The method was suggested by Brack, and tested by Schuman using prisoners in Block No. 10 in Auschwitz and Birkenau. Experiments were also performed by Brack on prisoners using the "window method". "Klauberg method"--injection of irritating materials into the uterus. Experiments were conducted using the plant Caladium Seguinum which was believed to have sterilization and castration properties.

  16. Sterile neutrino dark matter and low scale leptogenesis from a charged scalar.

    Science.gov (United States)

    Frigerio, Michele; Yaguna, Carlos E

    We show that novel paths to dark matter generation and baryogenesis are open when the standard model is extended with three sterile neutrinos [Formula: see text] and a charged scalar [Formula: see text]. Specifically, we propose a new production mechanism for the dark matter particle-a multi-keV sterile neutrino, [Formula: see text]-that does not depend on the active-sterile mixing angle and does not rely on a large primordial lepton asymmetry. Instead, [Formula: see text] is produced, via freeze-in, by the decays of [Formula: see text] while it is in equilibrium in the early Universe. In addition, we demonstrate that, thanks to the couplings between the heavier sterile neutrinos [Formula: see text] and [Formula: see text], baryogenesis via leptogenesis can be realized close to the electroweak scale. The lepton asymmetry is generated either by [Formula: see text]-decays for masses [Formula: see text] TeV, or by [Formula: see text]-oscillations for [Formula: see text] GeV. Experimental signatures of this scenario include an X-ray line from dark matter decays, and the direct production of [Formula: see text] at the LHC. This model thus describes a minimal, testable scenario for neutrino masses, the baryon asymmetry, and dark matter.

  17. Prospects for the future development and application of the sterile insect technique

    International Nuclear Information System (INIS)

    Robinson, A.S.; Hendrichs, J.

    2005-01-01

    Science-based modern agriculture and international trade in agricultural commodities have achieved that, even though the world population has doubled in the last 40 years, the absolute number of people in poverty and hunger has been falling steadily. The major challenge in the immediate future is to consolidate these positive gains, while simultaneously expanding environment-friendly agricultural practices. Within this context, the sterile insect technique (SIT), as part of area-wide integrated pest management (AW-IPM) programmes, will continue to gain momentum for application against certain key insect pests. This is in response to the demands for cleaner food and a better environment, the need to facilitate increasing international trade by overcoming pest related trade barriers to the movement of agricultural commodities, and the imperative of dealing with the increasing invasion of exotic pests. As the use of the technology increases, changes will continue to be made to improve the overall efficiency of the technique for those species where the SIT is already being used, and to expand the use of the technique to new key species. Modem biotechnology may also contribute to improving efficiency and, even though there are as yet no transgenic strains of pest insects that could be used in AW-IPM programmes, transgenic technology may eventually benefit these programmes in terms of strain marking, genetic sexing, molecular sterilization, and disease refractoriness; however, first the regulatory hurdle to allow their use will have to be overcome. There appears to be much promise in improving sterile male performance by exposing male insects to hormonal, nutritional, microbial, and semiochemical supplements. Furthermore, the management of mother colonies will be significantly improved to reduce the effects of colonization and to slow down mass-rearing effects on key behavioural parameters that often result in rapid colony deterioration. Progress will also need to be

  18. Eradication of sweet potato weevil using Co-60 gamma radiation

    International Nuclear Information System (INIS)

    Tokunaga, Taizo

    2007-01-01

    Sweet potato weevil which is a harmful insect injuring sweet potatoes was found out at Yoron Island in 1915 for the first time in Kagoshima prefecture, Japan. Here the eradication of sweet potato weevils using cobalt 60 irradiation achieved at Kikai Island is described. The mass-reared male weevils in potatoes are in pasture after sterilized by gamma irradiation. If the sexually sterile male copulates with a wild female, the egg does not incubate. By the repeated sterilization during several generations, the eradication of sweet potato weevils was accomplished. (M.H.)

  19. Sex separation strategies: past experience and new approaches

    Directory of Open Access Journals (Sweden)

    Malcolm Colin A

    2009-11-01

    Full Text Available Abstract The success of the sterile insect technique (SIT and other genetic strategies designed to eliminate large populations of insects relies on the efficient inundative releases of competitive, sterile males into the natural habitat of the target species. As released sterile females do not contribute to the sterility in the field population, systems for the efficient mass production and separation of males from females are needed. For vector species like mosquitoes, in which only females bite and transmit diseases, the thorough removal of females before release while leaving males competent to mate is a stringent prerequisite. Biological, genetic and transgenic approaches have been developed that permit efficient male-female separation for some species considered for SIT. However, most sex separation methods have drawbacks and many of these methods are not directly transferable to mosquitoes. Unlike genetic and transgenic systems, biological methods that rely on sexually dimorphic characters, such as size or development rate, are subject to natural variation, requiring regular adjustment and re-calibration of the sorting systems used. The yield can be improved with the optimization of rearing, but the scale of mass production places practical limits on what is achievable, resulting in a poor rearing to output ratio. High throughput separation is best achieved with scalable genetic or transgenic approaches.

  20. Effects of rearing density and dietary fat content on burst-swim performance and oxygen transport capacity in juvenile Atlantic salmon Salmo salar.

    Science.gov (United States)

    Hammenstig, D; Sandblom, E; Axelsson, M; Johnsson, J I

    2014-10-01

    The effects of hatchery rearing density (conventional or one third of conventional density) and feeding regime (high or reduced dietary fat levels) on burst-swim performance and oxygen transport capacity were studied in hatchery-reared Atlantic salmon Salmo salar, using wild fish as a reference group. There was no effect of rearing density or food regime on swimming performance in parr and smolts. The maximum swimming speed of wild parr was significantly higher than that of hatchery-reared conspecifics, while no such difference remained at the smolt stage. In smolts, relative ventricle mass was higher in wild S. salar compared with hatchery-reared fish. Moreover, wild S. salar had lower maximum oxygen consumption following a burst-swim challenge than hatchery fish. There were no effects of hatchery treatment on maximum oxygen consumption or relative ventricle mass. Haemoglobin and haematocrit levels, however, were lower in low-density fish than in fish reared at conventional density. Furthermore, dorsal-fin damage, an indicator of aggression, was similar in low-density reared and wild fish and lower than in S. salar reared at conventional density. Together, these results suggest that reduced rearing density is more important than reduced dietary fat levels in producing an S. salar smolt suitable for supplementary release. © 2014 The Fisheries Society of the British Isles.

  1. Reversibility of female sterilization.

    Science.gov (United States)

    Siegler, A M; Hulka, J; Peretz, A

    1985-04-01

    The discussion considers the current status of reversibility of sterilization in the US and describes clinical and experimental efforts for developing techniques designed for reversibility. It focuses on regret following sterilization, reversal potential of current sterilization techniques, patient selection, current reversal techniques, results of sterilization procedures, experimental approaches to reversal of current techniques of sterilization, and sterilization procedures devised for reversibility, in humans and in animals. Request is the 1st stage of reversal, but a request for sterilization reversal (SR) does not always mean regret for a decision made at the time. Frequently it is a wish to restore fertility because life circumstances have changed after a sterilization that was ppropriate at the time it was performed. Schwyhart and Kutner reviewed 22 studies published between 1949-69 in which they found that the percentage of patients regretting the procedure ranged from 1.3-15%. Requests for reversal remain low in most countries, but if sterilization becomes a more popular method of contraception, requests will also increase. The ideal operation considered as a reversaible method of sterilization should include an easy, reliable outpatient method of tubal occlusion with miniml risk or patient discomfort that subsequently could be reversed without the need for a major surgical intervention. Endoscopic methods have progressed toward the 1st objective. A recent search of the literature uncovered few series of SR of more than 50 cases. The 767 operations found were analyzed with regard to pregnancy outcome. The precent of live births varied from 74-78.8%, and the occurance of tubal pregnancies ranged from 1.7-6.5%. All of the confounding variables in patient selection and small numbers of reported procedures preclude any conclusion about the different techniques or the number of operations that give a surgeon a level of expertise. Few authors classify their

  2. Safety and efficacy of hysteroscopic sterilization compared with laparoscopic sterilization: an observational cohort study

    Science.gov (United States)

    Mao, Jialin; Pfeifer, Samantha; Schlegel, Peter

    2015-01-01

    Objective To compare the safety and efficacy of hysteroscopic sterilization with the “Essure” device with laparoscopic sterilization in a large, all-inclusive, state cohort. Design Population based cohort study. Settings Outpatient interventional setting in New York State. Participants Women undergoing interval sterilization procedure, including hysteroscopic sterilization with Essure device and laparoscopic surgery, between 2005 and 2013. Main outcomes measures Safety events within 30 days of procedures; unintended pregnancies and reoperations within one year of procedures. Mixed model accounting for hospital clustering was used to compare 30 day and 1 year outcomes, adjusting for patient characteristics and other confounders. Time to reoperation was evaluated using frailty model for time to event analysis. Results We identified 8048 patients undergoing hysteroscopic sterilization and 44 278 undergoing laparoscopic sterilization between 2005 and 2013 in New York State. There was a significant increase in the use of hysteroscopic procedures during this period, while use of laparoscopic sterilization decreased. Patients undergoing hysteroscopic sterilization were older than those undergoing laparoscopic sterilization and were more likely to have a history of pelvic inflammatory disease (10.3% v 7.2%, P<0.01), major abdominal surgery (9.4% v 7.9%, P<0.01), and cesarean section (23.2% v 15.4%, P<0.01). At one year after surgery, hysteroscopic sterilization was not associated with a higher risk of unintended pregnancy (odds ratio 0.84 (95% CI 0.63 to 1.12)) but was associated with a substantially increased risk of reoperation (odds ratio 10.16 (7.47 to 13.81)) compared with laparoscopic sterilization. Conclusions Patients undergoing hysteroscopic sterilization have a similar risk of unintended pregnancy but a more than 10-fold higher risk of undergoing reoperation compared with patients undergoing laparoscopic sterilization. Benefits and risks of both procedures

  3. Assessing the sampling strategy in the Northwestern Mediterranean Sea

    Science.gov (United States)

    Margirier, Félix; Testor, Pierre; Bosse, Anthony; Heslop, Emma; L'Hévéder, Blandine; Arsouze, Thomas; Houpert, Loic; Mortier, Laurent

    2017-04-01

    The deployment of numerous autonomous platforms (gliders, argo floats, moorings) added to the repeated ship cruises in the Northwestern Mediterranean Sea account for a considerable data coverage of the area through the past 10 years. In this study, we analyse the in-situ observations' ability to assess for the changes in the Northwester Mediterranean basin water masses properties over time. Comparing the observed time series for the different regions and different water masses to that of a glider simulator in the NEMO-Med12 model, we estimate both the quality of the model and the skill of the in-situ observations in reproducing the evolution of the basin properties.

  4. Radiation sterilization of medical products

    International Nuclear Information System (INIS)

    Khurshid, S.J.; Hussain, A.M.

    1989-01-01

    Radiation sterilization is the best method of sterilization, essentially for single use medical and surgical products. Pakistan has established a commercial gamma irradiation plant for this purpose. This article overviews the advantages and benefits of radiation sterilization to stimulate the interest of industrialists and the users in this technology. This technology can give a better medical care in the country and the growing demand can only be met by bulk sterilization. The radiation sterilized medical products can also compete well with the products sterilized by other methods in the international market, gamma sterilization is accepted internationally and if adopted it can boost our export of medical products. (author)

  5. Suppression of Mediterranean fruit fly populations over mountainous areas through aerial phloxine B - protein bait sprays: Regional Medfly programme in Guatemala

    International Nuclear Information System (INIS)

    McQuate, Grant T.; Peck, Steven L.

    2000-01-01

    spray. A second spray cycle was begun in December 1997, targeted to start before the annual Mediterranean fruit fly population increase. The sprays were continued until early February 1998, after which a weekly release of sterile Mediterranean fruit flies was started and was planned to continue through mid-June, 1998. Here, we describe the 1997-1998 large area phloxine B protein bait spray programme in southwestern Guatemala. We present the catch results of traps monitored throughout the weekly spray programme, as well as trap catch results from the initial ten weeks of sterile fly release which followed the spray programme. Additionally, we discuss issues which may affect the success of large area suppression programmes which target Mediterranean fruit fly or other tephritid fruit fly species using xanthene dye protein bait sprays

  6. Mass Evolution of Mediterranean, Black, Red, and Caspian Seas from GRACE and Altimetry: Accuracy Assessment and Solution Calibration

    Science.gov (United States)

    Loomis, B. D.; Luthcke, S. B.

    2016-01-01

    We present new measurements of mass evolution for the Mediterranean, Black, Red, and Caspian Seas as determined by the NASA Goddard Space Flight Center (GSFC) GRACE time-variable global gravity mascon solutions. These new solutions are compared to sea surface altimetry measurements of sea level anomalies with steric corrections applied. To assess their accuracy, the GRACE and altimetry-derived solutions are applied to the set of forward models used by GSFC for processing the GRACE Level-1B datasets, with the resulting inter-satellite range acceleration residuals providing a useful metric for analyzing solution quality.

  7. Modified Baryonic Dynamics: two-component cosmological simulations with light sterile neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Angus, G.W.; Gentile, G. [Department of Physics and Astrophysics, Vrije Universiteit Brussel, Pleinlaan 2, Brussels, 1050 Belgium (Belgium); Diaferio, A. [Dipartimento di Fisica, Università di Torino, Via P. Giuria 1, Torino, I-10125 Italy (Italy); Famaey, B. [Observatoire astronomique de Strasbourg, CNRS UMR 7550, Université de Strasbourg, 11 rue de l' Université, Strasbourg, F-67000 France (France); Heyden, K.J. van der, E-mail: garry.angus@vub.ac.be, E-mail: diaferio@ph.unito.it, E-mail: benoit.famaey@astro.unistra.fr, E-mail: gianfranco.gentile@ugent.be, E-mail: heyden@ast.uct.ac.za [Astrophysics, Cosmology and Gravity Centre, Dept. of Astronomy, University of Cape Town, Private Bag X3, Rondebosch, 7701 South Africa (South Africa)

    2014-10-01

    In this article we continue to test cosmological models centred on Modified Newtonian Dynamics (MOND) with light sterile neutrinos, which could in principle be a way to solve the fine-tuning problems of the standard model on galaxy scales while preserving successful predictions on larger scales. Due to previous failures of the simple MOND cosmological model, here we test a speculative model where the modified gravitational field is produced only by the baryons and the sterile neutrinos produce a purely Newtonian field (hence Modified Baryonic Dynamics). We use two-component cosmological simulations to separate the baryonic N-body particles from the sterile neutrino ones. The premise is to attenuate the over-production of massive galaxy cluster halos which were prevalent in the original MOND plus light sterile neutrinos scenario. Theoretical issues with such a formulation notwithstanding, the Modified Baryonic Dynamics model fails to produce the correct amplitude for the galaxy cluster mass function for any reasonable value of the primordial power spectrum normalisation.

  8. Short communication: Effects of summer rainfall variations on sheep body state and farming sustainability in sub-Mediterranean pastoral systems

    Directory of Open Access Journals (Sweden)

    Paola Scocco

    2016-08-01

    Full Text Available In sub-Mediterranean climate the grassland aboveground phytomass production peaks in late spring and drops in summer, when the decrease of the pasture feed value may lead to the worsening of the animal welfare. Our goal was to define the summer rainfall values leading to a decrease of semi-extensive farming system sustainability in sub-Mediterranean regions. Summer rainfall variations reflect in the aboveground phytomass production and on the sheep body state. Differences of body condition score (BCS among years were significant in late summer, which is the mating period for sheep. In the driest year the BCS of end August drops down to 2.1, largely below the value considered sufficient to ensure the animal breeding/milking performances (2.5. Reduction of summer rainfall greater than 15–20% compared to the normal average value (thus less than expected by the scenario of climate change might be detrimental for semi-extensive rearing sustainability in sub-Mediterranean climate.

  9. Short communication: Effects of summer rainfall variations on sheep body state and farming sustainability in sub-Mediterranean pastoral systems

    Energy Technology Data Exchange (ETDEWEB)

    Scocco, P.; Piermarteri, K.; Malfatti, A.; Tardella, F.M.; Catorci, A.

    2016-11-01

    In sub-Mediterranean climate the grassland aboveground phytomass production peaks in late spring and drops in summer, when the decrease of the pasture feed value may lead to the worsening of the animal welfare. Our goal was to define the summer rainfall values leading to a decrease of semi-extensive farming system sustainability in sub-Mediterranean regions. Summer rainfall variations reflect in the aboveground phytomass production and on the sheep body state. Differences of body condition score (BCS) among years were significant in late summer, which is the mating period for sheep. In the driest year the BCS of end August drops down to 2.1, largely below the value considered sufficient to ensure the animal breeding/milking performances (2.5). Reduction of summer rainfall greater than 15–20% compared to the normal average value (thus less than expected by the scenario of climate change) might be detrimental for semi-extensive rearing sustainability in sub-Mediterranean climate. (Author)

  10. Activity of gypsy moth dorsolateral neurosecretory neurons under increased rearing density

    Directory of Open Access Journals (Sweden)

    Mrdaković Marija

    2012-01-01

    Full Text Available Lymantria dispar caterpillars were reared under two different rearing densities for the first three days of the 4th larval instar: 5 larvae that were kept in a Petri dish (V = 80 ml belonged to the intense stress (D1 group; 5 larvae that were kept in a plastic cup (V = 300ml belonged to the group exposed to less intense stress (D2 group. In the control group, single larvae were reared in a Petri dish. Morphometric changes in L1, L2 and L2’ dorsolateral neurosecretory neurons (nsn were analyzed. After keeping 5 larvae in a Petri dish, the size of L2 neurosecretory neurons (nsn significantly increased. Rearing 5 larvae in a plastic cup significantly increased the size of L1 nsn nuclei and the number of L2’nsn. A decrease in relative band densities in the region of molecular masses (11-15 kD that correspond to prothoracicotropic hormones in the gypsy moth was observed in the electrophoretic profiles that were obtained after both treatments in comparison to the control group. [Acknowledgments. This study was supported by the Serbian Ministry of Education and Science (Grant No. 173027.

  11. Methods of sterilization and monitoring of sterilization across selected dental practices in karachi, pakistan

    International Nuclear Information System (INIS)

    Ahmed, H.

    2015-01-01

    To assess methods of sterilization in dental practices in Karachi and secondly to investigate methods of monitoring sterilization in dental practices in Karachi, Pakistan. Study Design: Cross-sectional, descriptive study. Place and Duration of Study: Dental colleges, hospitals and private clinics of Karachi, Pakistan, from January to March 2013. Methodology: A total of 251 questionnaires were obtained. Descriptive statistics were computed and differences between groups were assessed through chi-square test using Statistical Package for the Social Sciences (SPSS) version 16.0. P-value < 0.05 was taken as statistically significant. Results: Autoclave, used by 155 (61.8%) dentists was the most common method of sterilization followed by more than one method, 65 (25.9%); dry heat, 24 (9.6%); and cold sterilization, 7 (2.8%). Majority of dentists, 126 (50.1%), never monitored sterilization and those who did monitored mostly monthly. Statistically significant difference was found amongst the three groups of dentists monitoring sterilization (p=0.09) and methods of sterilization (p < 0.01). Conclusion: Statistically significant difference was found in infection control practices of specialists, postgraduate trainees and general dentists regarding method of monitoring sterilization with majority of dentists never monitoring sterilization. (author)

  12. Search for GeV-Scale Sterile Neutrinos Responsible for Active Neutrino Oscillations and Baryon Asymmetry of the Universe

    Directory of Open Access Journals (Sweden)

    S. N. Gninenko

    2012-01-01

    Full Text Available Standard Model fails to explain neutrino oscillations, dark matter, and baryon asymmetry of the Universe. All these problems can be solved with three sterile neutrinos added to SM. Quite remarkably, if sterile neutrino masses are well below the electroweak scale, this modification—Neutrino Minimal Standard Model (νMSM—can be tested experimentally. We discuss a new experiment on search for decays of GeV-scale sterile neutrinos, which are responsible for the matter-antimatter asymmetry generation and for the active neutrino masses. If lighter than 2 GeV, these particles can be produced in decays of charm mesons generated by high energy protons in a target, and subsequently decay into SM particles. To fully explore this sector of νMSM, the new experiment requires data obtained with at least 1020 incident protons on target (achievable at CERN SPS in future and a big volume detector constructed from a large amount of identical single modules, with a total sterile neutrino decay length of few kilometers. The preliminary feasibility study for the proposed experiment shows that it has sensitivity which may either lead to the discovery of new particles below the Fermi scale—right-handed partners of neutrinos—or rule out seesaw sterile neutrinos with masses below 2 GeV.

  13. Radiosterilization and gas sterilization

    International Nuclear Information System (INIS)

    Schultz, H.A.; Gruenewald, T.

    1987-01-01

    The book presents a survey of the principles of cold sterilization by radiation or gas, and also of the problems involved. The reader who has to do with sterilization of some kind or other, as e.g. sterilization of medicaments, medical supplies, medical device, drugs, grafts, or food, will find comprehensive information on the various available methods and their effects, as well as on monitoring procedures and techniques, together with proposals for efficient documentation and validation of partial sterilization processes. The introduction summarizes the potentials of sterilization by radiation, and the subsequent by radiation, and the subsequent chapters explain the specific applicabilities of radiosterilization along with the most important criteria for evaluating the sterilizing efficiency. The information on the legal situation and requirements takes into account the second amendment of the Medical Preparations Act. With 38 figs., 14 tabs [de

  14. Sterilization of health care products - Radiation. Part 2: Establishing the sterilization dose

    International Nuclear Information System (INIS)

    2006-01-01

    This part of ISO 11137 describes methods that may be used to establish the sterilization dose in accordance with one of the two approaches specified in 8.2 of ISO 11137-1:2006. The methods used in these approaches are: a) dose setting to obtain a product-specific dose; b) dose substantiation to verify a preselected dose of 25 kGy or 15 kGy. The basis of the dose setting methods described in this part of ISO 11137 (Methods 1 and 2) owe much to the ideas first propounded by Tallentire (Tallentire, 1973 [17]; Tallentire, Dwyer and Ley, 1971 [18]; Tallentire and Khan, 1978 [19]). Subsequently, standardized protocols were developed (Davis et al., 1981 [8]; Davis, Strawderman and Whitby, 1984 [9]) which formed the basis of the dose setting methods detailed in the AAMI Recommended Practice for Sterilization by Gamma Radiation (AAMI 1984, 1991 [4], [6]). Methods 1 and 2 and the associated sterilization dose audit procedures use data derived from the inactivation of the microbial population in its natural state on product. The methods are based on a probability model for the inactivation of microbial populations. The probability model, as applied to bioburden made up of a mixture of various microbial species, assumes that each such species has its own unique D 10 value. In the model, the probability that an item will possess a surviving microorganism after exposure to a given dose of radiation is defined in terms of the initial number of microorganisms on the item prior to irradiation and the D 10 values of the microorganisms. The methods involve performance of tests of sterility on product items that have received doses of radiation lower than the sterilization dose. The outcome of these tests is used to predict the dose needed to achieve a predetermined sterility assurance level, SAL. Methods 1 and 2 may also be used to substantiate 25 kGy if, on performing a dose setting exercise, the derived sterilization dose for an SAL of 10 -6 is u ≤25 kGy. The basis of the method

  15. Search for heavy sterile neutrinos in trileptons at the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Dib, Claudio O. [Univ. Tecnica Federico Santa Maria, Valparaiso (Chile). CCTVal y Dept. of Physics; Kim, C.S. [Yonsei Univ., Seoul (Korea, Republic of). Dept. of Physics and IPAP; Wang, Kechen [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Chinese Academy of Sciences, Beijing (China). Center for Future High Energy Physics

    2017-03-15

    We present a search strategy for both Dirac and Majorana sterile neutrinos from the purely leptonic decays of W{sup ±}→e{sup ±}e{sup ±}μ{sup -+}ν and μ{sup ±}μ{sup ±}e{sup -+}ν at the 14 TeV LHC. The discovery and exclusion limits for sterile neutrinos are shown using both the Cut-and-Count (CC) and Multi-Variate Analysis (MVA) methods. We also discriminate between Dirac and Majorana sterile neutrinos by exploiting a set of kinematic observables which differ between the Dirac and Majorana cases. We find that the MVA method, compared to the more common CC method, can greatly enhance the discovery and discrimination limits. Two benchmark points with sterile neutrino mass m{sub N}=20 GeV and 50 GeV are tested. For an integrated luminosity of 3000 fb{sup -1}, sterile neutrinos can be found with 5σ significance if heavy-to-light neutrino mixings vertical stroke U{sub Ne} vertical stroke {sup 2}∝ vertical stroke U{sub Nμ} vertical stroke {sup 2}∝10{sup -6}, while Majorana vs. Dirac discrimination can be reached if at least one of the mixings is of order 10{sup -5}.

  16. Dark-matter sterile neutrinos in models with a gauge singlet in the Higgs sector

    International Nuclear Information System (INIS)

    Petraki, Kalliopi; Kusenko, Alexander

    2008-01-01

    Sterile neutrino with mass of several keV can be the cosmological dark matter, can explain the observed velocities of pulsars, and can play an important role in the formation of the first stars. We describe the production of sterile neutrinos in a model with an extended Higgs sector, in which the Majorana mass term is generated by the vacuum expectation value of a gauge-singlet Higgs boson. In this model the relic abundance of sterile neutrinos does not necessarily depend on their mixing angles, the free-streaming length can be much smaller than in the case of warm dark matter produced by neutrino oscillations, and, therefore, some of the previously quoted bounds do not apply. The presence of the gauge singlet in the Higgs sector has important implications for the electroweak phase transition, baryogenesis, and the upcoming experiments at the Large Hadron Collider and a Linear Collider.

  17. Audits of radiation sterilization facilities

    International Nuclear Information System (INIS)

    Kelkar, Prabhakar M.

    2001-01-01

    Johnson and Johnson is the world leader in sterilization science and technology. A special group of scientists and technologists are engaged in the development of new methods of sterilization, worldwide monitoring of sterilization processes, equipment and approvals for all types of sterilization processes. Kilmer Conference in the alternate year for the benefit of all those involved in improvement in sterilization science is held. Cobalt-60 gamma radiation for sterilization of medical products on commercial scale is used. This kind of mammoth task can only be achieved through systematic method of planning, auditing, expert review and approval of facilities

  18. Male and female sterility in Zambia

    Directory of Open Access Journals (Sweden)

    Athena Pantazis

    2014-02-01

    Full Text Available Background: Population measures of sterility are traditionally constructed for women, despite fertility and sterility being conditions of the couple. Estimates of male sterility provide insight into population-level sterility, and complement estimates based solely on women. Objective: This study seeks to estimate male sterility for the Gwembe Tonga of Zambia using male birth histories collected by the Gwembe Tonga Research Project from 1957 to 1995, while providing context by estimating female sterility for the Gwembe Tonga, as well as female sterility in all of Zambia, from Zambian DHS data (1992, 1997, 2001-02, and 2007. Methods: Sterility is measured using the Larson-Menken subsequently infertile indicator. Estimates are produced using discrete time event history analysis. Results: The odds of sterility were higher for women than men, though women's odds of sterility were only 1.5 times that of men's in the middle reproductive years. The odds of sterility increased steadily with age for both men and women, and across all datasets. However, women's sterility increased much more sharply with age than men's did, and women's odds of sterility were higher than men's at all reproductive ages.

  19. High Genetic Diversity and Distinctiveness of Rear-Edge Climate Relicts Maintained by Ancient Tetraploidisation for Alnus glutinosa

    Science.gov (United States)

    Lepais, Olivier; Muller, Serge D.; Ben Saad-Limam, Samia; Benslama, Mohamed; Rhazi, Laila; Belouahem-Abed, Djamila; Daoud-Bouattour, Amina; Gammar, Amor Mokhtar; Ghrabi-Gammar, Zeineb; Bacles, Cécile Fanny Emilie

    2013-01-01

    Populations located at the rear-edge of a species’ distribution may have disproportionate ecological and evolutionary importance for biodiversity conservation in a changing global environment. Yet genetic studies of such populations remain rare. This study investigates the evolutionary history of North-African low latitude marginal populations of Alnus glutinosa Gaertn., a European tree species that plays a significant ecological role as a keystone of riparian ecosystems. We genotyped 551 adults from 19 populations located across North Africa at 12 microsatellite loci and applied a coalescent-based simulation approach to reconstruct the demographic and evolutionary history of these populations. Surprisingly, Moroccan trees were tetraploids demonstrating a strong distinctiveness of these populations within a species otherwise known as diploid. Best-fitting models of demographic reconstruction revealed the relict nature of Moroccan populations that were found to have withstood past climate change events and to be much older than Algerian and Tunisian populations. This study highlights the complex demographic history that can be encountered in rear-edge distribution margins that here consist of both old stable climate relict and more recent populations, distinctively diverse genetically both quantitatively and qualitatively. We emphasize the high evolutionary and conservation value of marginal rear-edge populations of a keystone riparian species in the context of on-going climate change in the Mediterranean region. PMID:24098677

  20. Radiation sterilization of medical devices

    International Nuclear Information System (INIS)

    Kaluska, I.; Stuglik, Z.

    1996-01-01

    Overview of sterilization methods of medical devices has been given, with the special stress put on radiation sterilization. A typical validation program for radiation sterilization has been shown and also a comparison of European and ISO standards concerning radiation sterilization has been discussed. (author). 13 refs, 1 fig., 2 tabs

  1. Combining the Sterile Insect Technique with the Incompatible Insect Technique: III-Robust Mating Competitiveness of Irradiated Triple Wolbachia-Infected Aedes albopictus Males under Semi-Field Conditions.

    Science.gov (United States)

    Zhang, Dongjing; Lees, Rosemary Susan; Xi, Zhiyong; Bourtzis, Kostas; Gilles, Jeremie R L

    2016-01-01

    Combination of the sterile insect technique with the incompatible insect technique is considered to be a safe approach to control Aedes albopictus populations in the absence of an accurate and scalable sex separation system or genetic sexing strain. Our previous study has shown that the triple Wolbachia-infected Ae. albopictus strain (wAlbA, wAlbB and wPip) was suitable for mass rearing and females could be completely sterilized as pupae with a radiation dose of at least 28 Gy. However, whether this radiation dose can influence the mating competitiveness of the triple infected males was still unknown. In this study we aimed to evaluate the effects of irradiation on the male mating competitiveness of the triple infected strain under laboratory and semi-field conditions. The results herein indicate that irradiation with a lower, female-sterilizing dose has no negative impact on the longevity of triple infected males while a reduced lifespan was observed in the wild type males (wAlbA and wAlbB) irradiated with a higher male-sterilizing dose, in small cages. At different sterile: fertile release ratios in small cages, triple-infected males induced 39.8, 81.6 and 87.8% sterility in a wild type female population at 1:1, 5:1 and 10:1 release ratios, respectively, relative to a fertile control population. Similarly, irradiated triple infected males induced 31.3, 70.5 and 89.3% sterility at 1:1, 5:1 and 10:1 release ratios, respectively, again relative to the fertile control. Under semi-field conditions at a 5:1 release ratio, relative to wild type males, the mean male mating competitiveness index of 28 Gy irradiated triple-infected males was significantly higher than 35 Gy irradiated wild type males, while triple infected males showed no difference in mean mating competitiveness to either irradiated triple-infected or irradiated wild type males. An unexpected difference was also observed in the relative male mating competitiveness of the triple infected strain after

  2. Sterile neutrinos in the early universe

    Energy Technology Data Exchange (ETDEWEB)

    Malaney, R.A. (Lawrence Livermore National Lab., CA (USA)); Fuller, G.M. (California Univ., San Diego, La Jolla, CA (USA). Dept. of Physics)

    1990-11-14

    We discuss the role played by right-handed sterile neutrinos in the early universe. We show how well known {sup 4}He constraint on the number of relativistic degrees of freedom at early times limits the equilibration of the right handed neutrino sea with the background plasma. We discuss how this allows interesting constraints to be placed on neutrino properties. In particular, a new limit on the Dirac mass of the neutrino is presented. 12 refs.

  3. Isolation of TDA-producing Phaeobacter strains from sea bass larval rearing units and their probiotic effect against pathogenic Vibrio spp. in Artemia cultures

    DEFF Research Database (Denmark)

    Grotkjær, Torben; Bentzon-Tilia, Mikkel; D'Alvise, Paul

    2016-01-01

    V. harveyi, which is the major bacterial pathogen in crustaceans and Mediterranean sea bass larvae cultures. Concomitantly, they significantly improved survival of V. harveyi-infected brine shrimp. 16S rRNA gene sequence homology identified the antagonists as Phaeobacter sp., and in silico DNA...... Vibrio anguillarum and reduce mortality in V. anguillarum-infected cod and turbot larvae. In this study, it was demonstrated that antagonistic Roseobacter-clade bacteria could be isolated from sea bass larval rearing units. In addition, it was shown that they not only antagonized V. anguillarum but also......-producing Phaeobacter isolated from Mediterranean marine larviculture are promising probiotic bacteria against pathogenic Vibrio in crustacean live-feed cultures for marine fish larvae....

  4. Search for sterile neutrinos in MINOS and MINOS+ using a two-detector fit

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P.; et al.

    2017-10-17

    A search for mixing between active neutrinos and light sterile neutrinos has been performed by looking for muon neutrino disappearance in two detectors at baselines of 1.04 km and 735 km, using a combined MINOS and MINOS+ exposure of $16.36\\times10^{20}$ protons-on-target. A simultaneous fit to the charged-current muon neutrino and neutral-current neutrino energy spectra in the two detectors yields no evidence for sterile neutrino mixing using a 3+1 model. The most stringent limit to date is set on the mixing parameter $\\sin^2\\theta_{24}$ for most values of the sterile neutrino mass-splitting $\\Delta m^2_{41} > 10^{-4}$ eV$^2$.

  5. Cosmology based on f(R) gravity admits 1 eV sterile neutrinos.

    Science.gov (United States)

    Motohashi, Hayato; Starobinsky, Alexei A; Yokoyama, Jun'ichi

    2013-03-22

    It is shown that the tension between recent neutrino oscillation experiments, favoring sterile neutrinos with masses of the order of 1 eV, and cosmological data which impose stringent constraints on neutrino masses from the free streaming suppression of density fluctuations, can be resolved in models of the present accelerated expansion of the Universe based on f(R) gravity.

  6. Evaluation of MALDI-TOF mass spectrometry and Sepsityper Kit™ for the direct identification of organisms from sterile body fluids in a Canadian pediatric hospital.

    Science.gov (United States)

    Tadros, Manal; Petrich, Astrid

    2013-01-01

    Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) can be used to identify bacteria directly from positive blood and sterile fluid cultures. The authors evaluated a commercially available kit - the Sepsityper Kit (Bruker Daltonik, Germany) - and MALDI-TOF MS for the rapid identification of organisms from 80 flagged positive blood culture broths, of which 73 (91.2%) were blood culture specimens and seven (8.7%) were cerebrospinal fluid specimens, in comparison with conventional identification methods. Correct identification to the genus and species levels was obtained in 75 of 80 (93.8%) and 39 of 50 (78%) blood culture broths, respectively. Applying the blood culture analysis module, a newly developed software tool, improved the species identification of Gram-negative organisms from 94.7% to 100% and of Gram-positive organisms from 66.7% to 70%. MALDI-TOF MS is a promising tool for the direct identification of organisms cultured from sterile sites.

  7. Evaluation of MALDI-TOF mass spectrometry and Sepsityper Kit™ for the direct identification of organisms from sterile body fluids in a Canadian pediatric hospital

    OpenAIRE

    Tadros, Manal; Petrich, Astrid

    2013-01-01

    Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) can be used to identify bacteria directly from positive blood and sterile fluid cultures. The authors evaluated a commercially available kit – the Sepsityper Kit (Bruker Daltonik, Germany) – and MALDI-TOF MS for the rapid identification of organisms from 80 flagged positive blood culture broths, of which 73 (91.2%) were blood culture specimens and seven (8.7%) were cerebrospinal fluid specimens, in com...

  8. Prospects of radiation sterilization of medical devices

    International Nuclear Information System (INIS)

    Hosobuchi, Kazunari

    1992-01-01

    Since radiation sterilization was first introduced in the United States in 1956 in the field of disposable medical devices, it has become an indispensable technique for sterilization because of the following reasons: (1) introduction into dialyzers, (2) introduction in medical device makers, (3) development of disposable medical devices associated with developing both high molecular chemistry and cool sterilization, (4) rationality of sterilization process, and (5) problems of sterilization with ethylene oxide gas. To promote the further development of radiation sterilization, the following items are considered necessary: (1) an increase in the number of facilities for radiation sterilization, (2) recommendation of the international standardization of sterilization method, (3) decrease in radiation doses associated with sterilization, (4) development of electron accelerators and bremsstrahlung equipments for radiation sources, and (5) simplification of sterilization process management. Factors precluding the development of radiation sterilization are: (1) development of other methods than radiation sterilization, (2) development of technique for sterile products, (3) high facility cost, (4) high irradiation cost, (5) benefits and limits of sterilization markets, and (6) influences of materials. (N.K.)

  9. Thermal sterilization of heat-sensitive products using high-temperature short-time sterilization.

    Science.gov (United States)

    Mann, A; Kiefer, M; Leuenberger, H

    2001-03-01

    High-temperature short-time (HTST) sterilization with a continuous-flow sterilizer, developed for this study, was evaluated. The evaluation was performed with respect to (a) the chemical degradation of two heat-sensitive drugs in HTST range (140-160 degrees C) and (b) the microbiological effect of HTST sterilization. Degradation kinetics of two heat-sensitive drugs showed that a high peak temperature sterilization process resulted in less chemical degradation for the same microbiological effect than a low peak temperature process. Both drugs investigated could be sterilized with acceptable degradation at HTST conditions. For the evaluation of the microbiological effect, Bacillus stearothermophilus ATCC 7953 spores were used as indicator bacteria. Indicator spore kinetics (D(T), z value, k, and E(a)), were determined in the HTST range. A comparison between the Bigelow model (z value concept) and the Arrhenius model, used to describe the temperature coefficient of the microbial inactivation, demonstrated that the Bigelow model is more accurate in prediction of D(T) values in the HTST range. The temperature coefficient decreased with increasing temperature. The influence of Ca(2+) ions and pH value on the heat resistance of the indicator spores, which is known under typical sterilization conditions, did not change under HTST conditions.

  10. Reconstructing Neutrino Mass Spectrum

    OpenAIRE

    Smirnov, A. Yu.

    1999-01-01

    Reconstruction of the neutrino mass spectrum and lepton mixing is one of the fundamental problems of particle physics. In this connection we consider two central topics: (i) the origin of large lepton mixing, (ii) possible existence of new (sterile) neutrino states. We discuss also possible relation between large mixing and existence of sterile neutrinos.

  11. A multi-signature approach to low-scale sterile neutrino phenomenology

    CERN Document Server

    Ross-Lonergan, Mark

    2017-01-01

    Since the discovery of non-zero neutrino masses, through the observation of neutrino flavour oscillations, we had a plethora of successful experiments which have made increasingly precise measurements of the mixing angles and mass-differences that drive the phenomena. In this thesis we highlight the fact that there is still significant room for new physics, however, when one removes the assumption of unitarity of the 3x3 neutrino mixing matrix, an assumption inherent in the 3ν paradigm. We refit all global data to show just how much non-unitarity is currently allowed. The canonical way that such a non-unitarity is introduced to the 3x3 neutrino mixing matrix is by the addition of additional neutral fermions, singlets under the Standard Model gauge group. These “Sterile Neutrinos” have a wide range of the- oretical and phenomenological implications. Alongside the sensitivity non-unitarity measurements have to sterile neutrinos, in this thesis we will study in detail two additional signatures of low-scale ...

  12. Male courtship behavior in Ceratitis Capitata (Diptera: Tephritidae) that have received Aromatherapy with ginger root oil

    International Nuclear Information System (INIS)

    Briceno, D.; Eberhard, W.; Shelly, T.

    2007-01-01

    The results of previous studies that showed that exposing mass-reared male Mediterranean fruit flies Ceratitis capitata (Wiedemann) to ginger root oil ('aromatherapy') increases the likelihood of mating with wild females were confirmed. The increased male success could be due to female responses to changes in male behavior or male pheromones. There were no significant differences in the types of courtship movements executed by males with and without aromatherapy. The durations of movements also did not differ when mass-reared males were paired with mass-reared females; however, when they were paired with wild females, there were a few, small differences. Previous studies indicated that the effectiveness of the male long-distance attractant pheromone is not affected by aromatherapy, but these studies did not consider pheromones released at close range during courtship, which behavioral analyses suggest may be different. We propose the following possible explanation for the different effects of aromatherapy with different females. Selection on males under mass rearing may have altered their close-range pheromones in ways that can be remedied by aromatherapy; and only wild females respond because the pheromonal responsiveness of mass-reared females has also changed. We propose observations that could test these ideas. (author) [es

  13. Sterilization in Finland: from eugenics to contraception.

    Science.gov (United States)

    Hemminki, E; Rasimus, A; Forssas, E

    1997-12-01

    The purpose of this paper was to describe the transition of sterilization in Finland from an eugenic tool to a contraceptive. Historical data were drawn from earlier reports in Finnish. Numbers of and reasons for sterilizations since 1950 were collected from nationwide sterilization statistics. Prevalence, characteristics of sterilized women, and women's satisfaction with sterilizations were studied from a 1994 nationwide survey (74% response rate). Logistic regression was used for adjustments. In the first half of the 20th century, eugenic ideology had influence in Finland as in other parts of Europe, and the 1935 and 1950 sterilization laws had an eugenic spirit. Regardless of this, the numbers of eugenic sterilizations remained low, and in practice, family planning was the main reason for sterilization. Nonetheless, prior to 1970 not all sterilizations were freely chosen, because sterilizations were sometimes used as a precondition for abortion. Female sterilizations showed remarkable fluctuation over time. Male sterilizations have been rare. The reasons stipulated by the law did not explain the numbers of sterilizations. In a 1994 survey, 9% of Finnish women reported they were using sterilization as their current contraceptive method (n = 189). Compared to women using other contraceptive methods, sterilized women were older, had had more births and pregnancies, and came from lower social classes. Sterilized women were satisfied with their sterilization, but there were women (8.5%) who regretted it. In conclusion, sterilizations have been and are likely to continue to be an important family planning method in Finland. The extreme gender ratio suggests a need for promoting male sterilizations, and women's expressed regrets suggest consideration of a higher age limit.

  14. Current initiatives in the mass production and field release of the Mexican fruit fly, Anastrepha ludens, in the lower Rio Grande valley of Texas

    International Nuclear Information System (INIS)

    Worley, J.N.; Forrester, O.T.

    1999-01-01

    In order to reduce the program operating expenses in the South Texas Mexican Fruit Fly Sterile Release Program, four cost reduction initiatives are in progress at the U.S. Department of Agriculture's Mexican Fruit Fly Rearing Facility. These initiatives include implementation of a less expensive larval diet formulation, automation of the larval diet dispensing process, processing and reutilization of spent larval diet medium, and a more efficient system for emerging and feeding sterile flies prior to field release. (author)

  15. Sterilization of space hardware.

    Science.gov (United States)

    Pflug, I. J.

    1971-01-01

    Discussion of various techniques of sterilization of space flight hardware using either destructive heating or the action of chemicals. Factors considered in the dry-heat destruction of microorganisms include the effects of microbial water content, temperature, the physicochemical properties of the microorganism and adjacent support, and nature of the surrounding gas atmosphere. Dry-heat destruction rates of microorganisms on the surface, between mated surface areas, or buried in the solid material of space vehicle hardware are reviewed, along with alternative dry-heat sterilization cycles, thermodynamic considerations, and considerations of final sterilization-process design. Discussed sterilization chemicals include ethylene oxide, formaldehyde, methyl bromide, dimethyl sulfoxide, peracetic acid, and beta-propiolactone.

  16. Regret following female sterilization in Slovenia.

    Science.gov (United States)

    Becner, Anja; Turkanović, Anela Bečić; But, Igor

    2015-07-01

    To estimate the regret rate and risk factors for regret among women who have undergone sterilization. A retrospective study was conducted among all women who underwent a sterilization procedure at the University Medical Center Maribor, Maribor, Slovenia, in 2008-2012. Identified women were contacted and asked to complete an online questionnaire assessing regret and symptoms associated with depression. Among 714 identified women, 308 (43.1%) completed the questionnaire. Four (1.3%) participants reported regret, and 9 (2.9%) reported that they would not opt for sterilization again, all of whom had post-sterilization problems. Such problems were significantly associated with participants reporting that they would not opt for sterilization again (P=0.003). Additionally, women who would not choose sterilization again had significantly higher scores on the depressive scale used than did those who would undergo sterilization again (P=0.028). Few women report regret after tubal sterilization in Slovenia. However, an additional consultation on post-sterilization problems and depressive disorder before sterilization might minimize the risk of regret. Copyright © 2015 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  17. Experimental Mycoplasma gallisepticum infections in captive-reared wild turkeys

    Science.gov (United States)

    Rocke, Tonie E.; Yuill, Thomas M.; Amundson, Terry E.

    1988-01-01

    The effects of Mycoplasma gallisepticum (MG) infections on egg production, fertility, and hatchability were studied in captive-reared wild turkeys (Meleagris gallopavo). Three groups of adult birds, each consisting of four hens and two toms, were exposed to MG by the respiratory route at the beginning of their breeding season. Fourteen control birds received sterile growth medium. Although no mortality of infected or control birds occurred, egg production during the first breeding season after infection was reduced. The mean number of eggs/hen/day produced by infected groups the first breeding season postexposure (PE) was significantly lower than the control value. The mean number of eggs produced daily by the same hens 1 yr later was unaffected by MG infection. The pecentage of fertile eggs produced by infected groups was slightly reduced in both the first and second breeding seasons PE. Hatchability of fertile eggs from infected hens was significantly lower than eggs from control hens. Productivity may be impaired if MG infections occur in free-ranging wild turkey populations.

  18. Production of a sterile species via active-sterile mixing: An exactly solvable model

    Science.gov (United States)

    Boyanovsky, D.

    2007-11-01

    The production of a sterile species via active-sterile mixing in a thermal medium is studied in an exactly solvable model. The exact time evolution of the sterile distribution function is determined by the dispersion relations and damping rates Γ1,2 for the quasiparticle modes. These depend on γ˜=Γaa/2ΔE, with Γaa the interaction rate of the active species in absence of mixing and ΔE the oscillation frequency in the medium without damping. γ˜≪1, γ˜≫1 describe the weak and strong damping limits, respectively. For γ˜≪1, Γ1=Γaacos⁡2θm; Γ2=Γaasin⁡2θm where θm is the mixing angle in the medium and the sterile distribution function does not obey a simple rate equation. For γ˜≫1, Γ1=Γaa and Γ2=Γaasin⁡22θm/4γ˜2, is the sterile production rate. In this regime sterile production is suppressed and the oscillation frequency vanishes at an Mikheyev-Smirnov-Wolfenstein (MSW) resonance, with a breakdown of adiabaticity. These are consequences of quantum Zeno suppression. For active neutrinos with standard model interactions the strong damping limit is only available near an MSW resonance if sin⁡2θ≪αw with θ the vacuum mixing angle. The full set of quantum kinetic equations for sterile production for arbitrary γ˜ are obtained from the quantum master equation. Cosmological resonant sterile neutrino production is quantum Zeno suppressed relieving potential uncertainties associated with the QCD phase transition.

  19. Cost-effectiveness analysis comparing the essure tubal sterilization procedure and laparoscopic tubal sterilization.

    Science.gov (United States)

    Thiel, John A; Carson, George D

    2008-07-01

    To analyze the financial implications of establishing a hysteroscopic sterilization program using the Essure micro-insert tubal sterilization system in an ambulatory clinic. A retrospective cohort study (Canadian Task Force classification Type II-2), in an ambulatory women's health clinic in a tertiary hospital, of 108 women undergoing Essure coil insertion between 2005 and 2006, and 104 women undergoing laparoscopic tubal sterilization for permanent sterilization between 2001 and 2004. The Essure procedures used a 4 mm single channel operative hysteroscope and conscious sedation (fentanyl and midazolam); the laparoscopic tubal sterilizations were completed under general anaesthesia with a 7 mm laparoscope and either bipolar cautery or Filshie clips. Costs associated with the procedure, follow-up, and management of any complications (including nursing, hospital charges, equipment, and disposables) were tabulated. The Essure coils were successfully placed on the first attempt in 103 of 108 women (95%). Three patients required a second attempt to complete placement and two patients required laparoscopic tubal sterilization after an unsuccessful Essure. All 104 laparoscopic tubals were completed on the first attempt with no complications reported. The total cost for the 108 Essure procedures, including follow-up evaluation, was $138,996 or $1287 per case. The total cost associated with the 104 laparoscopic tubal sterilization procedures was $148,227 or $1398 per case. The incremental cost-effectiveness ratio was $111. The Essure procedure in an ambulatory setting resulted in a statistically significant cost saving of $111 per sterilization procedure. Carrying out the Essure procedure in an ambulatory setting frees space in the operating room for other types of cases, improving access to care for more patients.

  20. Stability measurements of the electron gun for the KATRIN rear section

    Energy Technology Data Exchange (ETDEWEB)

    Ebenhoech, Sylvia [Karlsruhe Institute of Technology (KIT) (Germany). Institute for Technical Physics (ITEP), Tritium Laboratory Karlsruhe (TLK); Collaboration: KATRIN-Collaboration

    2016-07-01

    The aim of the KArlsruhe TRItium Neutrino (KATRIN) experiment is to determine the antineutrino mass with a sensitivity of 0.2 eV (90 % C.L.) by high-precision spectroscopy close to the tritium beta decay endpoint at 18.6 keV. To achieve the sensitivity aim both statistical and systematic uncertainties must be minimized. One contribution to the systematic error are uncertainties in the column density of the tritium source or in the source activity. In order to detect and monitor changes in the tritium source the Rear Section, which is integrated at the rear end of the KATRIN setup, is used. The Rear Section includes an angular selective electron gun (e-gun) based on the photoelectric effect. With the e-gun it will be possible e.g. to achieve a precise calibration of the column source density. To achieve the requirements on the e-gun a stable UV light source is essential to produce photoelectrons. The presentation focuses on the setup of the e-gun and intensity stability measurements of the UV light source setup.

  1. Mediterranean diet score and left ventricular structure and function: the Multi-Ethnic Study of Atherosclerosis.

    Science.gov (United States)

    Levitan, Emily B; Ahmed, Ali; Arnett, Donna K; Polak, Joseph F; Hundley, W Gregory; Bluemke, David A; Heckbert, Susan R; Jacobs, David R; Nettleton, Jennifer A

    2016-09-01

    Data are limited on the relation between dietary patterns and left ventricular (LV) structure and function. We examined cross-sectional associations of a diet-score assessment of a Mediterranean dietary pattern with LV mass, volume, mass-to-volume ratio, stroke volume, and ejection fraction. We measured LV variables with the use of cardiac MRI in 4497 participants in the Multi-Ethnic Study of Atherosclerosis study who were aged 45-84 y and without clinical cardiovascular disease. We calculated a Mediterranean diet score from intakes of fruit, vegetables, nuts, legumes, whole grains, fish, red meat, the monounsaturated fat:saturated fat ratio, and alcohol that were self-reported with the use of a food-frequency questionnaire. We used linear regression with adjustment for body size, physical activity, and cardiovascular disease risk factors to model associations and assess the shape of these associations (linear or quadratic). The Mediterranean diet score had a slight U-shaped association with LV mass (adjusted means: 146, 145, 146, and 147 g across quartiles of diet score, respectively; P-quadratic trend = 0.04). The score was linearly associated with LV volume, stroke volume, and ejection fraction: for each +1-U difference in score, LV volume was 0.4 mL higher (95% CI: 0.0, 0.8 mL higher), the stroke volume was 0.5 mL higher (95% CI: 0.2, 0.8 mL higher), and the ejection fraction was 0.2 percentage points higher (95% CI: 0.1, 0.3 percentage points higher). The score was not associated with the mass-to-volume ratio. A higher Mediterranean diet score is cross-sectionally associated with a higher LV mass, which is balanced by a higher LV volume as well as a higher ejection fraction and stroke volume. Participants in this healthy, multiethnic sample whose dietary patterns most closely conformed to a Mediterranean-type pattern had a modestly better LV structure and function than did participants with less-Mediterranean-like dietary patterns. This trial was registered at

  2. Sterile neutrinos with secret interactions—lasting friendship with cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Xiaoyong [International Center for Theoretical Physics, Strada Costiera 11, Trieste, 34014 Italy (Italy); Dasgupta, Basudeb [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, 400005 India (India); Kopp, Joachim, E-mail: xchu@ictp.it, E-mail: bdasgupta@theory.tifr.res.in, E-mail: jkopp@uni-mainz.de [PRISMA Cluster of Excellence and Mainz Institute for Theoretical Physics, Johannes Gutenberg University, Staudingerweg 7, Mainz, 55128 Germany (Germany)

    2015-10-01

    Sterile neutrinos with mass ≅ 1 eV and order 10% mixing with active neutrinos have been proposed as a solution to anomalies in neutrino oscillation data, but are tightly constrained by cosmological limits. It was recently shown that these constraints are avoided if sterile neutrinos couple to a new MeV-scale gauge boson A'. However, even this scenario is restricted by structure formation constraints when A'-mediated collisional processes lead to efficient active-to-sterile neutrino conversion after neutrinos have decoupled. In view of this, we reevaluate in this paper the viability of sterile neutrinos with such ''secret'' interactions. We carefully dissect their evolution in the early Universe, including the various production channels and the expected modifications to large scale structure formation. We argue that there are two regions in parameter space—one at very small A' coupling, one at relatively large A' coupling—where all constraints from big bang nucleosynthesis (BBN), cosmic microwave background (CMB), and large scale structure (LSS) data are satisfied. Interestingly, the large A' coupling region is precisely the region that was previously shown to have potentially important consequences for the small scale structure of dark matter halos if the A' boson couples also to the dark matter in the Universe.

  3. Sterilizing insects with ionizing radiation

    International Nuclear Information System (INIS)

    Bakri, A.; Mehta, K.; Lance, D.R.

    2005-01-01

    Exposure to ionizing radiation is currently the method of choice for rendering insects reproductively sterile for area-wide integrated pest management (AW-IPM) programmes that integrate the sterile insect technique (SIT). Gamma radiation from isotopic sources (cobalt-60 or caesium-137) is most often used, but high-energy electrons and X-rays are other practical options. Insect irradiation is safe and reliable when established safety and quality-assurance guidelines are followed. The key processing parameter is absorbed dose, which must be tightly controlled to ensure that treated insects are sufficiently sterile in their reproductive cells and yet able to compete for mates with wild insects. To that end, accurate dosimetry (measurement of absorbed dose) is critical. Irradiation data generated since the 1950s, covering over 300 arthropod species, indicate that the dose needed for sterilization of arthropods varies from less than 5 Gy for blaberid cockroaches to 300 Gy or more for some arctiid and pyralid moths. Factors such as oxygen level, and insect age and stage during irradiation, and many others, influence both the absorbed dose required for sterilization and the viability of irradiated insects. Consideration of these factors in the design of irradiation protocols can help to find a balance between the sterility and competitiveness of insects produced for programmes that release sterile insects. Many programmes apply 'precautionary' radiation doses to increase the security margin of sterilization, but this overdosing often lowers competitiveness to the point where the overall induced sterility in the wild population is reduced significantly. (author)

  4. Eugenics and Involuntary Sterilization: 1907-2015.

    Science.gov (United States)

    Reilly, Philip R

    2015-01-01

    In England during the late nineteenth century, intellectuals, especially Francis Galton, called for a variety of eugenic policies aimed at ensuring the health of the human species. In the United States, members of the Progressive movement embraced eugenic ideas, especially immigration restriction and sterilization. Indiana enacted the first eugenic sterilization law in 1907, and the US Supreme Court upheld such laws in 1927. State programs targeted institutionalized, mentally disabled women. Beginning in the late 1930s, proponents rationalized involuntary sterilization as protecting vulnerable women from unwanted pregnancy. By World War II, programs in the United States had sterilized approximately 60,000 persons. After the horrific revelations concerning Nazi eugenics (German Hereditary Health Courts approved at least 400,000 sterilization operations in less than a decade), eugenic sterilization programs in the United States declined rapidly. Simplistic eugenic thinking has faded, but coerced sterilization remains widespread, especially in China and India. In many parts of the world, involuntary sterilization is still intermittently used against minority groups.

  5. Guidelines for the Use of Mathematics in Operational Area-Wide Integrated Pest Management Programmes Using the Sterile Insect Technique with a Special Focus on Tephritid Fruit Flies

    International Nuclear Information System (INIS)

    Barclay, H.L.; Enkerlin, W.R.; Manoukis, N.C.; Reyes-Flores, J.

    2016-01-01

    This guideline attempts to assist managers in the use of mathematics in area-wide Integrated Pest Management (AW-IPM) programmes using the Sterile Insect Technique (SIT). It describes mathematical tools that can be used at different stages of suppression/eradication programmes. For instance, it provides simple methods for calculating the various quantities of sterile insects required in the intervention area so that more realistic sterile: fertile rates to suppress pest populations can be achieved. The calculations, for the most part, only involve high school mathematics and can be done easily with small portable computers or calculators. The guideline is intended to be a reference book, to be consulted when necessary. As such, any particular AW-IPM programme using the SIT will probably only need certain sections, and much of the book can be ignored if that is the case. For example, if the intervention area is relatively small and well isolated, then the section on dispersal can safely be ignored, as the boundedness of the area means that dispersal should not be a problem, and so the section on diffusion equations can be ignored. An overview is given in each chapter to try to let the programme manager make a decision about where to put the programme efforts. On the other hand, most SIT programmes have an information system (many of them based on GIS) that produces reliable profiles of historic information. Based on the results of past activities they describe what has happened in the last days or weeks but usually do not explain, or barely explain, what is expected in the following days or weeks. Current AW-IPM progammes using the SIT have produced over many years a vast amount of every-day data from the field operations and from the mass rearing facility and packing and sterile insect releasing centres. With the help of this guideline, that information can be used to develop predictive models for their particular conditions to better plan control measures.

  6. Male mating biology

    NARCIS (Netherlands)

    Howell, Paul I.; Knols, Bart G. J.

    2009-01-01

    Before sterile mass-reared mosquitoes are released in an attempt to control local populations, many facets of male mating biology need to be elucidated. Large knowledge gaps exist in how both sexes meet in space and time, the correlation of male size and mating success and in which arenas matings

  7. arXiv Search for sterile neutrinos decaying into pions at the LHC

    CERN Document Server

    Dib, Claudio O.; Neill, Nicolás A.; Yuan, Xing-Bo

    2018-02-28

    We study the possibility to observe sterile neutrinos with masses in the range 5  GeVmass region is difficult to explore with inclusive ℓℓjj modes or trilepton modes and impossible to explore in rare meson decays. While particle identification is a real challenge in these modes, vertex displacement due to the long living neutrino in the above mass range can greatly help reduce backgrounds. Assuming a sample of 109  W bosons at the end of the LHC Run 2, these modes could discover a sterile neutrino in the above mass range or improve the current bounds on the heavy-to-light lepton mixings by an order of magnitude, |UℓN|2∼2×10-6. Moreover, by studying the equal s...

  8. Development of female medfly attractant systems for trapping and sterility assessment. Proceedings of a final research co-ordination meeting

    International Nuclear Information System (INIS)

    1999-07-01

    Practical application of the sterile insect technique (SIT) against major insect pests will continue to increase as the repeated use of insecticides is recognized as an environmental problem. In the case of the Mediterranean fruit fly (medfly), which attacks over 300 species of fruits and vegetables in tropical, subtropical, and temperate climates on all five continents, control is still largely based on frequent insecticide spraying, often more than 10 sprays per fruiting season. Methods for population estimation, which accurately reflect changes due to movement, mortality or reproduction, are a prerequisite for effective pest management and in particular for use of SIT. With better monitoring tools medfly populations can be estimated more accurately and compared under different conditions, to guide decisions on alternative (i.e. more effective and more environment-friendly) control strategies. In support of this need in the application of SIT field programmes against medfly, an FAO/IAEA co-ordinated research project (CRP) was carried out which resulted in a TECDOC published in 1996 on Standardization of Medfly Trapping for Use in sterile insect technique Programmes. Following the development of male only genetic sexing strains at the FAO/IAEA Agriculture and Biotechnology Laboratories in Seibersdorf, Austria, it was recognized that the development of a female medfly targeted trapping system, in conjunction with only male sterile releases, would improve the efficacy of the SIT, reduce costs, and more effectively utilize sterile males. As a result, a new FAO/IAEA Co-ordinated Research Project on Development of Female Medfly Attractant Systems for Trapping and Sterility Assessment was initiated in 1994 with the objective to develop new synthetic female medfly attractants and to determine their efficacy compared to proteinaceous baits under different weather, host-tree and population density conditions. Findings obtained during the course of this 5-year CRP are

  9. Development of female medfly attractant systems for trapping and sterility assessment. Proceedings of a final research co-ordination meeting

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    Practical application of the sterile insect technique (SIT) against major insect pests will continue to increase as the repeated use of insecticides is recognized as an environmental problem. In the case of the Mediterranean fruit fly (medfly), which attacks over 300 species of fruits and vegetables in tropical, subtropical, and temperate climates on all five continents, control is still largely based on frequent insecticide spraying, often more than 10 sprays per fruiting season. Methods for population estimation, which accurately reflect changes due to movement, mortality or reproduction, are a prerequisite for effective pest management and in particular for use of SIT. With better monitoring tools medfly populations can be estimated more accurately and compared under different conditions, to guide decisions on alternative (i.e. more effective and more environment-friendly) control strategies. In support of this need in the application of SIT field programmes against medfly, an FAO/IAEA co-ordinated research project (CRP) was carried out which resulted in a TECDOC published in 1996 on Standardization of Medfly Trapping for Use in sterile insect technique Programmes. Following the development of male only genetic sexing strains at the FAO/IAEA Agriculture and Biotechnology Laboratories in Seibersdorf, Austria, it was recognized that the development of a female medfly targeted trapping system, in conjunction with only male sterile releases, would improve the efficacy of the SIT, reduce costs, and more effectively utilize sterile males. As a result, a new FAO/IAEA Co-ordinated Research Project on Development of Female Medfly Attractant Systems for Trapping and Sterility Assessment was initiated in 1994 with the objective to develop new synthetic female medfly attractants and to determine their efficacy compared to proteinaceous baits under different weather, host-tree and population density conditions. Findings obtained during the course of this 5-year CRP are

  10. Rear-facing car seat (image)

    Science.gov (United States)

    A rear-facing car seat position is recommended for a child who is very young. Extreme injury can occur in an accident because ... child. In a frontal crash a rear-facing car seat is best, because it cradles the head, ...

  11. Search for the sterile neutrino mixing with the ICAL detector at INO

    Energy Technology Data Exchange (ETDEWEB)

    Behera, S.P. [Bhabha Atomic Research Centre, Nuclear Physics Division, Mumbai (India); Homi Bhabha National Institute, Mumbai (India); Ghosh, Anushree [Universidad Tecnica Federico Santa Maria, Departamento de Fisica, Valparaiso (Chile); Choubey, Sandhya [Harish-Chandra Research Institute, Allahabad (India); Datar, V.M. [INO Cell, Tata Institute of Fundamental Research, Mumbai (India); Mishra, D.K. [Bhabha Atomic Research Centre, Nuclear Physics Division, Mumbai (India); Mohanty, A.K. [Bhabha Atomic Research Centre, Nuclear Physics Division, Mumbai (India); Homi Bhabha National Institute, Mumbai (India); Saha Institute of Nuclear Physics, Kolkata (India)

    2017-05-15

    The study has been carried out on the prospects of probing the sterile neutrino mixing with the magnetized iron calorimeter (ICAL) at the India-based Neutrino Observatory (INO), using atmospheric neutrinos as a source. The so-called 3 + 1 scenario is considered for active-sterile neutrino mixing and lead to projected exclusion curves in the sterile neutrino mass and mixing angle plane. The analysis is performed using the neutrino event generator NUANCE, modified for ICAL, and folded with the detector resolutions obtained by the INO collaboration from a full GEANT4-based detector simulation. A comparison has been made between the results obtained from the analysis considering only the energy and zenith angle of the muon and combined with the hadron energy due to the neutrino induced event. A small improvement has been observed with the addition of the hadron information to the muon. In the analysis we consider neutrinos coming from all zenith angles and the Earth matter effects are also included. The inclusion of events from all zenith angles improves the sensitivity to sterile neutrino mixing by about 35% over the result obtained using only down-going events. The improvement mainly stems from the impact of Earth matter effects on active-sterile mixing. The expected precision of ICAL on the active-sterile mixing is explored and the allowed confidence level (C.L.) contours presented. At the assumed true value of 10 {sup circle} for the sterile mixing angles and marginalization over Δm{sup 2}{sub 41} and the sterile mixing angles, the upper bound at 90% C.L. (from two-parameter plots) is around 20 {sup circle} for θ{sub 14} and θ{sub 34}, and about 12 {sup circle} for θ{sub 24}. (orig.)

  12. Gas-exchange patterns of Mediterranean fruit fly Pupae (Diptera: Tephritidae): A tool to forecast developmental stage

    International Nuclear Information System (INIS)

    Nestel, D.; Nemny-Lavy, E.; Alchanatis, V.

    2007-01-01

    The pattern of gas-exchange (CO 2 emission) was investigated for developing Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) pupae incubated at different temperatures. This study was undertaken to explore the usefulness of gas-exchange systems in the determination of physiological age in developing pupae that are mass produced for sterile insect technique projects. The rate of CO 2 emission was measured in a closed flow-through system connected to commercial infrared gas analysis equipment. Metabolic activity (rate of CO 2 emission) was related to pupal eye-color, which is the current technique used to determine physiological age. Eye-color was characterized digitally with 3 variables (Hue, Saturation and Intensity), and color separated by discriminant analysis. The rate of CO 2 emission throughout pupal development followed a U-shape, with high levels of emission during pupariation, pupal transformation and final pharate adult stages. Temperature affected the development time of pupae, but not the basic CO 2 emission patterns during development. In all temperatures, rates of CO 2 emission 1 and 2 d before adult emergence were very similar. After mid larval-adult transition (e.g., phanerocephalic pupa), digital eye-color was significantly correlated with CO 2 emission. Results support the suggestion that gas-exchange should be explored further as a system to determine pupal physiological age in mass production of fruit flies. (author) [es

  13. On the Mediterranean Sea inter-basin exchanges and nutrient dynamics

    Science.gov (United States)

    Rupolo, V.; Ribera D'Alcalà, M.; Iudicone, D.; Artale, V.

    2009-04-01

    The Mediterranean Sea is an evaporative basin in which the deficit of water is supplied by the inflow from the Gibraltar Strait of Atlantic Water. The net result of the air sea interactions in the entire basin is an outflow at Gibraltar of a salty water that is mainly constituted by the Levantin Intermediate Water, formed in the eastern part of the basin. Despite this simplified pattern, the circulation in the Mediterranean is rather complex. Most of the Mediterranean sub-basins are characterized by water mass formation processes and the presence of sills and straits strongly influence both the spreading and the mixing of intermediate and deep waters. In this context a Lagrangian diagnostics applied to numerical results was used to quantify mass transport in the main pathways of the upper and lower cells of the Mediterranean thermohaline circulation as they results from OGCM simulations. Lagrangian diagnostics reveals to be very useful to quantify both transports between different regions and the associated spectrum of transit times by means of pdf distribution of particles transit times between the different regions of the basin. This method is very effective to estimate the contribution of different water masses in isopycnal and diapycnal transformation processes and in reconstructing the fate of tracers. We use here these previous results on the basin circulation for better understanding the nutrient dynamics within the basin where the inputs from the different sources (atmosphere, runoff and open ocean) have similar order of magnitude. This, to the aim of building scenarios on the impact of climate driven changes in elemental fluxes to the basin on the internal nutrient dynamics.

  14. Effects of the Mediterranean diet and exercise in subjects with coronary artery disease.

    Science.gov (United States)

    Noites, Andreia; Pinto, Joana; Freitas, Carla Patrícia; Melo, Cristina; Albuquerque, Aníbal; Teixeira, Madalena; Mesquita Bastos, José

    2015-11-01

    The association of the Mediterranean diet and exercise appears to have a protective role, reducing cardiovascular risk. This study investigated the effects of education sessions on the Mediterranean diet and an exercise program in modifying eating behaviors, body composition and abdominal fat. An experimental study was performed on 20 subjects with known coronary heart disease randomly assigned to experimental (n=10) and control (n=10) groups. Both groups received education sessions on the Mediterranean diet, but the experimental group also followed an eight-week program of specific exercises. A semiquantitative food frequency questionnaire was administered to analyze food intake, bioimpedance was used to measure weight, fat mass and lean mass, and waist circumference was measured to calculate waist-to-height ratio. After eight weeks, protein (pdiet reduced carbohydrate and saturated fat intake, reflected in reduced fat mass. The association of the exercise program showed additional benefits in reduction of protein and cholesterol intake and abdominal fat. Copyright © 2015 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  15. The influence of increased rearing density on medial protocerebral neurosecretory neurons of Lymantria dispar L. caterpillars

    Directory of Open Access Journals (Sweden)

    Ilijin Larisa

    2010-01-01

    Full Text Available Morphometric changes of A1, A1' and A2 protocerebral dorsomedial neurosecretory neurons, total brain protein content and brain protein profiles were analyzed in 4th instar Lymantria dispar larvae under elevated rearing density, i.e. under intense stress when 5 larvae were kept in a petri dish (V = 80 ml, less intense stress when 5 larvae were kept in a plastic cup (V = 300 ml. In the control samples the larvae were reared in isolated conditions. Protein pattern changes in the brain were observed. Proteins with the following molecular masses: 30, 14, 10 and 3.4-2.5 kD were detected in the experimental groups. The size and cytological characteristics of protocerebral dorsomedial neurosecretory neurons were changed under elevated rearing density.

  16. Mediterranean fruit fly: interference of oviposition by radiation-sterilized females in field cages

    Energy Technology Data Exchange (ETDEWEB)

    McInnis, D. O. [Tropical Fruit and Vegetable Research Lab. USDA-ARS, Honolulu, HI (United States); Wong, T. T.Y.

    1990-07-01

    In experiments between April and September 1984, the behaviour of nonirradiated and radiation-sterilized laboratory-adapted adults of the tephritid Ceratitis capitata was observed on apples hung on guava trees in outdoor cages in Hawaii. The numbers of nonirradiated females observed resting on fruit were reduced several times by the presence of irradiated females, either alone or with irradiated males, but not by irradiated males alone. Similarly, the number of nonirradiated females observed ovipositing and the duration of oviposition was reduced by the presence of irradiated females. In control cages (all nonirradiated flies), the duration of oviposition by females averaged 255.9±15.0 s on fruit, while most of nonirradiated and irradiated females in the mixed (treatment) cage averaged 157±19.8 s and 77.5±7.5 s on fruit, resp. Irradiated females behaved skittishly on fruit and frequently engaged in physical encounters with other flies.

  17. Sterile insect technique: A model for dose optimisation for improved sterile insect quality

    International Nuclear Information System (INIS)

    Parker, A.; Mehta, K.

    2007-01-01

    The sterile insect technique (SIT) is an environment-friendly pest control technique with application in the area-wide integrated control of key pests, including the suppression or elimination of introduced populations and the exclusion of new introductions. Reproductive sterility is normally induced by ionizing radiation, a convenient and consistent method that maintains a reasonable degree of competitiveness in the released insects. The cost and effectiveness of a control program integrating the SIT depend on the balance between sterility and competitiveness, but it appears that current operational programs with an SIT component are not achieving an appropriate balance. In this paper we discuss optimization of the sterilization process and present a simple model and procedure for determining the optimum dose. (author) [es

  18. Preparing the way for coming area wide integrated pest management projects against the new world screwworm, Cochliomyia hominivorax, in MERCOSUR

    Energy Technology Data Exchange (ETDEWEB)

    Mastrangelo, Thiago; Fernandes, Thiago; Walder, Julio, E-mail: piaui@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Bezerra, Fernando [Instituto Federal de Educacao, Ciencia e Tecnologia do Sertao Pernambucano (IFSERTAO-PE), Petrolina, PE (Brazil)

    2011-07-01

    The New World Screwworm (NWS), Cochliomyia hominivorax, was eradicated from the USA, Central America to Panama, but in most tropical regions of Latin America, the NWS is still a serious threat to livestock, provoking estimated annual losses of US$ 1.8 billion in Brazil. Between January and May 2009, a pilot-project was performed at the Brazil-Uruguay border. As the results were positive, novel regional Area-Wide Integrated Pest Management projects are being planned. To set a mass-rearing center based in South America is strategic when considering long-term programs. In partnership with CENA/USP and the Biofactory MOSCAMED Brazil, a project to produce sterile NWS started on 2009. The project aimed to maintain a colony of a regional NWS strain, to develop a mass-rearing system and a sterilization protocol by X rays, and to study the sterility induction in regional strains. A colony was successfully established. The adults were kept in cages and fed on a diet (honey and spray dried egg). The larvae were reared in a medium made of spray dried blood, spray dried egg, milk, water, formalin and Ecogel. Egg hatch has been of 80 {+-} 10%. From F{sub 1} to F{sub 22}, the total amount of pupae produced was about 38 L ({approx} 315,400 pupae). The mean adult emergence and sex ratio were 86.7 {+-} 3% and 0.59 {+-} 0.08 respectively. The mean pupal weight was 47.1 {+-} 1.7 mg. The estimated X ray doses to induce 99% sterility in males and females were 43.7 Gy and 47.5 Gy, respectively. To produce 1.5 L of pupae, the current cost is about US$ 15.00. (author)

  19. Preparing the way for coming area wide integrated pest management projects against the new world screwworm, Cochliomyia hominivorax, in MERCOSUR

    International Nuclear Information System (INIS)

    Mastrangelo, Thiago; Fernandes, Thiago; Walder, Julio; Bezerra, Fernando

    2011-01-01

    The New World Screwworm (NWS), Cochliomyia hominivorax, was eradicated from the USA, Central America to Panama, but in most tropical regions of Latin America, the NWS is still a serious threat to livestock, provoking estimated annual losses of US$ 1.8 billion in Brazil. Between January and May 2009, a pilot-project was performed at the Brazil-Uruguay border. As the results were positive, novel regional Area-Wide Integrated Pest Management projects are being planned. To set a mass-rearing center based in South America is strategic when considering long-term programs. In partnership with CENA/USP and the Biofactory MOSCAMED Brazil, a project to produce sterile NWS started on 2009. The project aimed to maintain a colony of a regional NWS strain, to develop a mass-rearing system and a sterilization protocol by X rays, and to study the sterility induction in regional strains. A colony was successfully established. The adults were kept in cages and fed on a diet (honey and spray dried egg). The larvae were reared in a medium made of spray dried blood, spray dried egg, milk, water, formalin and Ecogel. Egg hatch has been of 80 ± 10%. From F 1 to F 22 , the total amount of pupae produced was about 38 L (∼ 315,400 pupae). The mean adult emergence and sex ratio were 86.7 ± 3% and 0.59 ± 0.08 respectively. The mean pupal weight was 47.1 ± 1.7 mg. The estimated X ray doses to induce 99% sterility in males and females were 43.7 Gy and 47.5 Gy, respectively. To produce 1.5 L of pupae, the current cost is about US$ 15.00. (author)

  20. Pain Associated With Hysteroscopic Sterilization

    Science.gov (United States)

    Levy, Jenna; Childers, Meredith E.

    2007-01-01

    Background and Objectives: The safety and efficacy of female hysteroscopic sterilization using the Essure system has been well documented. Given the marked differences in the execution of hysteroscopic and laparoscopic sterilization, the objective of this study was to assess the experience of pain postprocedure between the 2. Secondary end-points included postoperative pain medication, time to return to normal activities, postprocedure bleeding, and patient satisfaction. Methods: Twenty cases each of laparoscopic sterilization (LS) and hysteroscopic sterilization (HS) were performed. Patients were surveyed regarding their experience of pain immediately postoperatively, 1 week, and 4 weeks post-procedure. Results: The average pain score immediately postprocedure was significantly lower among HS patients than among LS patients (t=−8.17, P<.0001). One-week post-procedure, none of the patients in the HS group reported any pain, while the average pain score among the LS patients was 2.65 (t =−9.67, P<.0001). Four weeks post-procedure, women in the HS group continued to report no pain, 35% of the LS group continued to report some pain (t=−3.04, P=.004). Conclusions: Hysteroscopic sterilization offers a minimally invasive, less painful, equally efficacious modality for sterilization than laparoscopic sterilization and should be available to all women seeking permanent birth control. PMID:17651558

  1. Women plan condom use after sterilization.

    Science.gov (United States)

    1998-12-01

    Sexual sterilization is highly effective in preventing pregnancy, but it does not protect against sexually transmitted diseases (STDs). People who accept sterilization as their method of family planning therefore need to be encouraged to protect themselves against HIV/AIDS and STDs even after they have been sterilized. Since women return less often to family planning providers following their sterilization procedure, they need to be advised to protect themselves against HIV and STDs before the sterilization is performed. 42% of the 2782 women who underwent tubal sterilizations at the Baylor College of Medicine in Houston during 1991-96 indicated their intention in a cross-sectional study to use condoms after sterilization. 20% of all respondents, aged 18-51 years, had a known risk factor for HIV, and almost 25% reported regular condom use for contraception or disease protection during the 3 months before sterilization. Planned condom use increased from 32% in 1991 to 51% in 1996, irrespective of age, marital status, or ethnic background. Of the 646 women who used condoms before being sterilized, almost half indicated no plans to do so after the procedure. The following factors were associated with condom use: relatively younger age, black ethnicity, unmarried status, history of previous STD, no steady partner, having a higher number of previous sex partners, past use of condoms to prevent disease transmission, and lack of partner involvement in the decision to undergo sterilization.

  2. Pathogenecity of Ichthyophonus hoferi for laboratory-reared Pacific herring (Clupea pallasi) and its early appearance in wild Puget Sound herring

    Science.gov (United States)

    Kocan, R.; Hershberger, P.; Mehl, T.; Elder, N.; Bradley, M.; Wildermuth, D.; Stick, K.

    1999-01-01

    Laboratory-reared pathogen-free Pacific herring were exposed to pure cultures of Ichthyophonus hoferi, and reproduced the disease seen in naturally infected fish--thus fulfilling Koch's Postulates. Pathogen-free herring used in this study were reared from artificially spawned eggs incubated in filtered, UV-sterilized seawater, eliminating the variables associated with multiple infections, which are common in wild herring. Wild free-ranging herring were captured monthly from June through October by dip net from 'herring balls' located in the northern Puget Sound. I. hoferi infections were identified in these fish soon after metamorphoses, about 4 mo post-hatch. The prevalence increased from 5 to 6% in 0-yr fish to 24% in 1-yr-old fish to 50 to 70% in fish over 2 yr old, with no associated increase in mortality. The route of natural transmission to wild herring was not determined, but carnivorous fish became infected and died when they were experimentally fed tissues infected with the organism. In vitro culture of tissues was the most sensitive method for identifying both clinical and subclinical infections.

  3. Pathogenicity of Ichthyophonus hoferi for laboratory-reared Pacific herring Clupea pallasi and its early appearance in wild Puget Sound herring.

    Science.gov (United States)

    Kocan, R M; Hershberger, P; Mehl, T; Elder, N; Bradley, M; Wildermuth, D; Stick, K

    1999-01-07

    Laboratory-reared pathogen-free Pacific herring were exposed to pure cultures of Ichthyophonus hoferi, and reproduced the disease seen in naturally infected fish--thus fulfilling Koch's Postulates. Pathogen-free herring used in this study were reared from artificially spawned eggs incubated in filtered, UV-sterilized seawater, eliminating the variables associated with multiple infections, which are common in wild herring. Wild free-ranging herring were captured monthly from June through October by dip net from 'herring balls' located in the northern Puget Sound. I. hoferi infections were identified in these fish soon after metamorphoses, about 4 mo post-hatch. The prevalence increased from 5 to 6% in 0-yr fish to 24% in 1-yr-old fish to 50 to 70% in fish over 2 yr old, with no associated increase in mortality. The route of natural transmission to wild herring was not determined, but carnivorous fish became infected and died when they were experimentally fed tissues infected with the organism. In vitro culture of tissues was the most sensitive method for identifying both clinical and subclinical infections.

  4. Pathogenicity of Ichthyophonus hoferi for laboratory-reared Pacific herring Clupea pallasi and its early appearance in wild Puget Sound herring

    Science.gov (United States)

    Kocan, R.M.; Hershberger, P.; Mehl, T.; Elder, N.; Bradley, M.; Wildermuth, D.; Stick, K.

    1999-01-01

    Laboratory-reared pathogen-free Pacific herring were exposed to pure cultures of Ichthyophonus hoferi, and reproduced the disease seen in naturally infected fish - thus fulfilling Koch's Postulates. Pathogen-free herring used in this study were reared from artificially spawned eggs incubated in filtered, UV-sterilized seawater, eliminating the variables associated with multiple infections, which are common in wild herring. Wild free-ranging herring were captured monthly from June through October by dip net from 'herring balls' located in the northern Puget Sound. I. hoferi infections were identified in these fish soon after metamorphoses, about 4 mo post-hatch. The prevalence increased from 5 to 6% in 0-yr fish to 24% in 1-yr-old fish to 50 to 70% in fish over 2 yr old, with no associated increase in mortality. The route of natural transmission to wild herring was not determined, but carnivorous fish became infected and died when they were experimentally fed tissues infected with the organism. In vitro culture of tissues was the most sensitive method for identifying both clinical and subclinical infections.

  5. Neutrino masses, leptogenesis and dark matter from small lepton number violation?

    Energy Technology Data Exchange (ETDEWEB)

    Abada, Asmaa [CNRS, Univ. Paris-Sud, Univ. Paris-Saclay, Orsay (France). Lab. de Physique Theorique; Arcadi, Giorgio [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Domcke, Valerie [Paris Diderot Univ. (France). AstroParticule et Cosmologie (APC)/Paris Centre for Cosmological Physics (PCCP); Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Lucente, Michele [Univ. Catholique de Louvain, Louvain-la-Neuve (Belgium). Centre for Cosmology, Particle Physics and Phenomenology (CP3)

    2017-09-05

    We consider the possibility of simultaneously addressing the baryon asymmetry of the Universe, the dark matter problem and the neutrino mass generation in minimal extensions of the Standard Model via sterile fermions with (small) total lepton number violation. Within the framework of Inverse and Linear Seesaw models, the small lepton number violating parameters set the mass scale of the active neutrinos, the efficiency of leptogenesis through a small mass splitting between pairs of sterile fermions as well as the mass scale of a sterile neutrino dark matter candidate. We provide an improved parametrization of these seesaw models taking into account existing experimental constraints and derive a linearized system of Boltzmann equations to describe the leptogenesis process, which allows for an efficient investigation of the parameter space. This in particular enables us to perform a systematic study of the strong washout regime of leptogenesis. Our study reveals that one can have a successful leptogenesis at the temperature of the electroweak scale through oscillations between two sterile states with a natural origin of the (necessary) strong degeneracy in their mass spectrum. The minimal model however requires a non-standard cosmological history to account for the relic dark matter. Finally, we discuss the prospect for neutrinoless double beta decay and for testing, in future experiments, the values of mass and different active-sterile mixings required for successful leptogenesis.

  6. Neutrino masses, leptogenesis and dark matter from small lepton number violation?

    Science.gov (United States)

    Abada, Asmaa; Arcadi, Giorgio; Domcke, Valerie; Lucente, Michele

    2017-12-01

    We consider the possibility of simultaneously addressing the baryon asymmetry of the Universe, the dark matter problem and the neutrino mass generation in minimal extensions of the Standard Model via sterile fermions with (small) total lepton number violation. Within the framework of Inverse and Linear Seesaw models, the small lepton number violating parameters set the mass scale of the active neutrinos, the efficiency of leptogenesis through a small mass splitting between pairs of sterile fermions as well as the mass scale of a sterile neutrino dark matter candidate. We provide an improved parametrization of these seesaw models taking into account existing experimental constraints and derive a linearized system of Boltzmann equations to describe the leptogenesis process, which allows for an efficient investigation of the parameter space. This in particular enables us to perform a systematic study of the strong washout regime of leptogenesis. Our study reveals that one can have a successful leptogenesis at the temperature of the electroweak scale through oscillations between two sterile states with a natural origin of the (necessary) strong degeneracy in their mass spectrum. The minimal model however requires a non-standard cosmological history to account for the relic dark matter. Finally, we discuss the prospect for neutrinoless double beta decay and for testing, in future experiments, the values of mass and different active-sterile mixings required for successful leptogenesis.

  7. Neutrino masses, leptogenesis and dark matter from small lepton number violation?

    International Nuclear Information System (INIS)

    Abada, Asmaa; Domcke, Valerie; Lucente, Michele

    2017-01-01

    We consider the possibility of simultaneously addressing the baryon asymmetry of the Universe, the dark matter problem and the neutrino mass generation in minimal extensions of the Standard Model via sterile fermions with (small) total lepton number violation. Within the framework of Inverse and Linear Seesaw models, the small lepton number violating parameters set the mass scale of the active neutrinos, the efficiency of leptogenesis through a small mass splitting between pairs of sterile fermions as well as the mass scale of a sterile neutrino dark matter candidate. We provide an improved parametrization of these seesaw models taking into account existing experimental constraints and derive a linearized system of Boltzmann equations to describe the leptogenesis process, which allows for an efficient investigation of the parameter space. This in particular enables us to perform a systematic study of the strong washout regime of leptogenesis. Our study reveals that one can have a successful leptogenesis at the temperature of the electroweak scale through oscillations between two sterile states with a natural origin of the (necessary) strong degeneracy in their mass spectrum. The minimal model however requires a non-standard cosmological history to account for the relic dark matter. Finally, we discuss the prospect for neutrinoless double beta decay and for testing, in future experiments, the values of mass and different active-sterile mixings required for successful leptogenesis.

  8. Sterilization by gamma irradiation

    International Nuclear Information System (INIS)

    Reyes Frias, L.

    1992-01-01

    Since 1980 the National Institute of Nuclear Research counts with an Industrial Gamma Irradiator, for the sterilization of raw materials and finished products. Through several means has been promoted the use of this technology as alternative to conventional methods of sterilization as well as steam treatment and ethylene oxide. As a result of the made promotion this irradiator has come to its saturation limit being the sterilization irradiation one of the main services that National Institute of Nuclear Research offers to producer enterprises of disposable materials of medical use also of raw materials for the elaboration of cosmetic products and pharmaceuticals as well as dehydrated foods. It is presented the trend to the sterilization service by irradiation showed by the compilation data in a survey made by potential customers. (Author)

  9. Mass rearing and augmentative biological control evaluation of Rhynocoris fuscipes (Hemiptera: Reduviidae) against multiple pests of cotton.

    Science.gov (United States)

    Tomson, Majesh; Sahayaraj, Kitherian; Kumar, Vivek; Avery, Pasco B; McKenzie, Cindy L; Osborne, Lance S

    2017-08-01

    Rhynocoris fuscipes (Fab.) (Hemiptera: Reduviidae) is a generalist predator of cotton pests and is commonly found inhabiting cotton-growing regions in southern India. With the goal of integrating this predator in standard management practices used against cotton pests on a commercial scale, (1) we developed a protocol for adult group rearing of this predator inside micro-environmental cages (MECs), and (2) we evaluated the biocontrol potential of mass-produced predators against cotton pests under potted and field conditions. Higher fecundity and adult longevity of R. fuscipes was recorded in the MECs than under natural growing conditions. The reduviid predator preferred stones and fallen leaves as hiding places in the MECs. The predator showed a higher biocontrol potential during the night hours against two pests, Phenacoccus solenopsis Tinsley and Dysdercus cingulatus (Fab.), than during the day under potted conditions. Under field conditions, R. fuscipes significantly reduced the population of Aphis gossypii Glover, P. solenopsis, D. cingulatus and Helicoverpa armigera (Hübner) by 28, 70, 29 and 50%, respectively. No negative impact of R. fuscipes was reported on other natural enemies present in the cotton agroecosystem. Significantly higher crop yield and cost benefit ratio were observed in R. fuscipes-released plots than in the control plots. The results suggest that R. fuscipes can be mass produced efficiently under controlled conditions in MECs, and used in an integrated management program for multiple cotton pests. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  10. Non-unitarity, sterile neutrinos, and non-standard neutrino interactions

    Energy Technology Data Exchange (ETDEWEB)

    Blennow, Mattias [Department of Theoretical Physics, School of Engineering Sciences, KTH Royal Institute of Technology, Albanova University Center, 106 91 Stockholm (Sweden); Coloma, Pilar [Theoretical Physics Department, Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); Fernandez-Martinez, Enrique; Hernandez-Garcia, Josu [Departamento de Física Teórica, Universidad Autónoma de Madrid, Cantoblanco E-28049 Madrid (Spain); Instituto de Física Teórica UAM/CSIC, Calle Nicolás Cabrera 13-15, Cantoblanco E-28049 Madrid (Spain); Lopez-Pavon, Jacobo [INFN, Sezione di Genova, via Dodecaneso 33, 16146 Genova (Italy); CERN, Theoretical Physics Department, Geneva (Switzerland)

    2017-04-27

    The simplest Standard Model extension to explain neutrino masses involves the addition of right-handed neutrinos. At some level, this extension will impact neutrino oscillation searches. In this work we explore the differences and similarities between the case in which these neutrinos are kinematically accessible (sterile neutrinos) or not (mixing matrix non-unitarity). We clarify apparent inconsistencies in the present literature when using different parametrizations to describe these effects and recast both limits in the popular neutrino non-standard interaction (NSI) formalism. We find that, in the limit in which sterile oscillations are averaged out at the near detector, their effects at the far detector coincide with non-unitarity at leading order, even in presence of a matter potential. We also summarize the present bounds existing in both limits and compare them with the expected sensitivities of near-future facilities taking the DUNE proposal as a benchmark. We conclude that non-unitarity effects are too constrained to impact present or near future neutrino oscillation facilities but that sterile neutrinos can play an important role at long baseline experiments. The role of the near detector is also discussed in detail.

  11. Male gametophytic sterility. 1 - Gametic sterilities and deletions in petunia

    Energy Technology Data Exchange (ETDEWEB)

    Cornu, A.; Maizonnier, D. (Station d' Amelioration des Plantes de l' I.N.R.A., Dijon (France))

    1982-01-01

    Terminal deletions induced by ionizing radiations in Petunia are not sexually transmitted. Cytogenetic study of plants with a heterozygous deletion and their progenies shows that this lack of transmission is accompanied by a gametic semi-sterility due to the fact that gametes carrying the deleted chromosome are not viable. The interest of such a male sterility with a gametophytic determinism for the study of sporophyte-gametophyte relationships is underlined.

  12. Annual report 1998

    International Nuclear Information System (INIS)

    1998-01-01

    In two key areas, genetic sexing in the medfly, Ceratitis capitata, and mass rearing of the tsetse, Glossina pallidipes, 1998 has been a year of consolidation. For medfly, programme managers now view the use of genetic sexing strains - (GSS) as an integral part of the Sterile Insect Technique (SIT) for control and/or eradication of this pest. Since its introduction only 4 years ago, this technology is having an increasing impact on the implementation of medfly SIT. For tsetse, a rearing system has been designed and tested which will form the basic rearing module for the mass rearing facility to be built in Addis Ababa, Ethiopia. The system is cheap, easy to maintain and can be locally constructed. The facility in Addis Ababa will produce sterile G. pallidipes males for the SIT component of a large tsetse eradication programme in the Southern Rift valley. The Unit will continue to play a unique role in the further development of these technology transfer programmes. The Unit continues to maintain many strains of tsetse and medfly which are used to supply numerous institutions and individuals with biological material for research work. In addition, medfly GSS are provided to operational SIT programmes as required. This support provided to Member States, especially in the area of tsetse research, appears to be of increasing importance as the number of requests rise each year. All of this material is provided free of charge

  13. [Paper on sterilization in the family planning programs of Colombia: a national debate].

    Science.gov (United States)

    Rizo, A; Roper, L

    1986-01-01

    During 1984, family planning became the object of heated public debate in Colombia. In particular, considerable controversy surrounded the practice of sterilization. In Colombia in 1980, 49% of married women were practicing family planning. The main protagonist has been Profamilia, an IPPF affliate, which runs clinics and advisory services throughout Colombia. Sterilization is performed quite extensively on men of at least 28 years and women of 25 with 3 living children. Further activities of Profamilia include community distribution and social marketing programs. Many of the health facilities used are those of the Ministry of Public Health. The Minister of Health responded to criticism levelled by the Catholic church and others by instituting an investigation into alleged practices of mass sterilization. Profamilia declared publicy that sterilization was performed only under certain conditions, after waiting periods, and under no circumstances with coersion. Various groups including medical associations publicy supported Profamilia. Although recognizing the need for families to be limited in size, religious and other commentators suggested that sterilization was often presented as a solution to family ills, and that it represented foreign involvement in Colombian social policy. The opposing opinions were that church-supported natural family planning was not an effective enough strategy. The ministry has resolved to invoke more stringent screening of women desiring sterilization to include natural family planning in its programs, and to deal with international organizations only on the ministry level. The number of sterilizations has diminished. The controversy helped to expose political weaknesses of Profamilia's programs (e.g. the use of monetary incentives; lack of supervision).

  14. Gamma-ray irradiation, autoclave and ethylene oxide sterilization to thermosetting polyurethane: sterilization to polyurethane

    International Nuclear Information System (INIS)

    Hirata, Noriko; Matsumoto, Ken-Ichi; Inishita, Takashi; Takenaka, Yoshinori; Suma, Yasunori; Shintani, Hideharu; National Inst. of Health Sciences, Tokyo

    1995-01-01

    Thermosetting polyurethane (PU) is widely used in a large variety of medical devices. 4,4'-methylenedianiline (MDA) was produced from PU by sterilization and it was studied for the relationship between urethane components or polymer characteristics and formation of MDA upon sterilization, using the commercially available dialyzers fabricated with different combination of isocyanate and polyol. We confirmed that the molecular-weight of polyol influenced the production of MDA upon sterilization. (author)

  15. Phenology, sterility and inheritance of two environment genic male sterile (EGMS) lines for hybrid rice.

    Science.gov (United States)

    El-Namaky, R; van Oort, P A J

    2017-12-01

    There is still limited quantitative understanding of how environmental factors affect sterility of Environment-conditioned genic male sterility (EGMS) lines. A model was developed for this purpose and tested based on experimental data from Ndiaye (Senegal) in 2013-2015. For the two EGMS lines tested here, it was not clear if one or more recessive gene(s) were causing male sterility. This was tested by studying sterility segregation of the F2 populations. Daylength (photoperiod) and minimum temperatures during the period from panicle initiation to flowering had significant effects on male sterility. Results clearly showed that only one recessive gene was involved in causing male sterility. The model was applied to determine the set of sowing dates of two different EGMS lines such that both would flower at the same time the pollen would be completely sterile. In the same time the local popular variety (Sahel 108, the male pollen donor) being sufficiently fertile to produce the hybrid seeds. The model was applied to investigate the viability of the two line breeding system in the same location with climate change (+2oC) and in two other potential locations: in M'Be in Ivory Coast and in the Nile delta in Egypt. Apart from giving new insights in the relation between environment and EGMS, this study shows that these insights can be used to assess safe sowing windows and assess the suitability of sterility and fertility period of different environments for a two line hybrid rice production system.

  16. Materials Surfaces and sterility

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, R.

    2001-04-01

    A question of great interest in sterile and clean room technology is how can we devise a standard for the guarantee of sterility? Sterility is of widespread importance: it gives the life-time of our daily milk or yogurt, dominates the nature of food packing, and determines the feasibility of the miniaturization of biotechnology plants. All these phenomena are based on the principle of bioadhesion. Bioadhesion is also the basis of the biomimetic material technologies, like the attachment of selected protein layers that can be used for nanomasking. (orig.)

  17. Large-scale Mass Transport Deposits in the Valencia Basin (Western Mediterranean): slope instability induced by rapid sea-level drawdown?

    Science.gov (United States)

    Cameselle, Alejandra L.; Urgeles, Roger; Llopart, Jaume

    2014-05-01

    The Messinian Salinity Crisis (MSC) strongly affected the physiography of the Mediterranean margins at the end of the Miocene. The sharp sea-level fall gave a new configuration to the Mediterranean basin and created dramatic morphological and sedimentological changes: margins have been largely eroded whereas the deep basins accumulated thick evaporitic and detrital units. Amongst these detrital units, there are evidences on seismic reflection data for major large-scale slope failure of the Mediterranean continental margins. About 2700 km of seismic reflection profiles in the southwestern part of the Valencia Basin (Western Mediterranean) have enabled us the detailed mapping of distinctive Messinian erosional surfaces, evaporites and deep detrital deposits. The detrital deposits occur in a distinct unit that is made of chaotic, roughly-bedded or transparent seismic bodies, which have been mainly mapped in the basin domain. Locally, the seismic unit shows discontinuous high-amplitude reflections and/or an imbricate internal structure. This unit is interpreted to be formed by a series of Mass Transport Deposits (MTDs). Rapid drawdown has long been recognized as one of the most severe loadings conditions that a slope can be subjected to. Several large historical slope failures have been documented to occur due to rapid drawdown in dams, riverbanks and slopes. During drawdown, the stabilizing effect of the water on the upstream face is lost, but the pore-water pressures within the slope may remain high. The dissipation of these pore pressures in the slope is controlled by the permeability and the storage characteristics of the slope sediments. We hypothesize that the MTDs observed in our data formed under similar conditions and represent a large-scale equivalent of this phenomenon. Therefore, these MTDs can be used to put some constraints on the duration of the drawdown phase of the MSC. We have performed a series of slope stability analysis under rapid Messinian sea

  18. Sterile neutrinos with secret interactions — lasting friendship with cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Xiaoyong [International Center for Theoretical Physics,Strada Costiera 11, Trieste, 34014 (Italy); Dasgupta, Basudeb [Tata Institute of Fundamental Research,Homi Bhabha Road, Mumbai, 400005 (India); Kopp, Joachim [PRISMA Cluster of Excellence and Mainz Institute for Theoretical Physics,Johannes Gutenberg University, Staudingerweg 7, Mainz, 55128 (Germany)

    2015-10-06

    Sterile neutrinos with mass ≃1 eV and order 10% mixing with active neutrinos have been proposed as a solution to anomalies in neutrino oscillation data, but are tightly constrained by cosmological limits. It was recently shown that these constraints are avoided if sterile neutrinos couple to a new MeV-scale gauge boson A{sup ′}. However, even this scenario is restricted by structure formation constraints when A{sup ′}-mediated collisional processes lead to efficient active-to-sterile neutrino conversion after neutrinos have decoupled. In view of this, we reevaluate in this paper the viability of sterile neutrinos with such “secret” interactions. We carefully dissect their evolution in the early Universe, including the various production channels and the expected modifications to large scale structure formation. We argue that there are two regions in parameter space — one at very small A{sup ′} coupling, one at relatively large A{sup ′} coupling — where all constraints from big bang nucleosynthesis (BBN), cosmic microwave background (CMB), and large scale structure (LSS) data are satisfied. Interestingly, the large A{sup ′} coupling region is precisely the region that was previously shown to have potentially important consequences for the small scale structure of dark matter halos if the A{sup ′} boson couples also to the dark matter in the Universe.

  19. Steam sterilization does not require saturated steam

    NARCIS (Netherlands)

    van Doornmalen Gomez Hoyos, J. P.C.M.; Paunovic, A.; Kopinga, K.

    2017-01-01

    The most commonly applied method to sterilize re-usable medical devices in hospitals is steam sterilization. The essential conditions for steam sterilization are derived from sterilization in water. Microbiological experiments in aqueous solutions have been used to calculate various time–temperature

  20. Autonomy, Educational Plans, and Self-Esteem in Institution-Reared and Home-Reared Teenagers in Estonia

    Science.gov (United States)

    Tulviste, Tiia

    2011-01-01

    The study examines autonomy, self-esteem, and educational plans for the future of 109 institution-reared and 106 home-reared teenagers (15-19 years). Teenagers were asked to complete the Teen Timetable Scale (Feldman & Rosenthal), two Emotional Autonomy Scales (Steinberg & Silverberg), the Rosenberg Self-Esteem Scale, and answer questions…

  1. Thermalizing Sterile Neutrino Dark Matter.

    Science.gov (United States)

    Hansen, Rasmus S L; Vogl, Stefan

    2017-12-22

    Sterile neutrinos produced through oscillations are a well motivated dark matter candidate, but recent constraints from observations have ruled out most of the parameter space. We analyze the impact of new interactions on the evolution of keV sterile neutrino dark matter in the early Universe. Based on general considerations we find a mechanism which thermalizes the sterile neutrinos after an initial production by oscillations. The thermalization of sterile neutrinos is accompanied by dark entropy production which increases the yield of dark matter and leads to a lower characteristic momentum. This resolves the growing tensions with structure formation and x-ray observations and even revives simple nonresonant production as a viable way to produce sterile neutrino dark matter. We investigate the parameters required for the realization of the thermalization mechanism in a representative model and find that a simple estimate based on energy and entropy conservation describes the mechanism well.

  2. Thermalizing Sterile Neutrino Dark Matter

    Science.gov (United States)

    Hansen, Rasmus S. L.; Vogl, Stefan

    2017-12-01

    Sterile neutrinos produced through oscillations are a well motivated dark matter candidate, but recent constraints from observations have ruled out most of the parameter space. We analyze the impact of new interactions on the evolution of keV sterile neutrino dark matter in the early Universe. Based on general considerations we find a mechanism which thermalizes the sterile neutrinos after an initial production by oscillations. The thermalization of sterile neutrinos is accompanied by dark entropy production which increases the yield of dark matter and leads to a lower characteristic momentum. This resolves the growing tensions with structure formation and x-ray observations and even revives simple nonresonant production as a viable way to produce sterile neutrino dark matter. We investigate the parameters required for the realization of the thermalization mechanism in a representative model and find that a simple estimate based on energy and entropy conservation describes the mechanism well.

  3. Preliminary comparison of different immune and production components in local and imported Saanen goats reared under a sub-tropical environment.

    Science.gov (United States)

    Barbour, Elie K; Itani, Houssam H; Sleiman, Fawwak T; Saade, Maya F; Harakeh, Steve; Nour, Afif M Abdel; Shaib, Houssam A

    2012-01-01

    Three objectives were included in this research work. The first objective compared different immune components in healthy mature males, mature females, and female kids of local and imported Saanen goats, reared under a sub-tropical environment. The significantly differing immune components were the blood monocyte percent, blood CD8 count, and the total white blood cell count. The second objective compared the performance of Saanen versus local does. The means of the milk yield and prolificacy of the imported Saanen does were significantly higher than those of the local does (pgoats on protection potential against prevalent diseases in the sub-tropical zone of the eastern Mediterranean countries is discussed.

  4. Comparison of longevity between a laboratory strain and a natural population of Anastrepha Fraterculus (Diptera: Tephritidae) under field cage conditions

    International Nuclear Information System (INIS)

    Gomez Cendra, P.; Vilardi, J.; Segura, D.; Cladera, J.; Allinghi, A.

    2007-01-01

    The South American fruit fly Anastrepha fraterculus (Wiedemann) is one of the most destructive fruit pests in this region, infesting major fruit crops. Implementation of the sterile insect technique (SIT) as part of an area-wide integrated approach against this species requires information on the survival of mass-reared and sterilized insects in the field and their ability to mate with wild females. The survival rates in field cages of both non-irradiated and irradiated laboratory flies were compared with that of wild flies. Both types of laboratory flies survived longer than their wild counterparts over the 8 days under the experimental conditions. The irradiation dose (70 Gy) did not affect survival of the laboratory reared flies. Our results improve the prospect of integrating the SIT into the control of A. fraterculus populations in Argentina. (author) [es

  5. Assessing forest vulnerability to climate warming using a process-based model of tree growth: bad prospects for rear-edges.

    Science.gov (United States)

    Sánchez-Salguero, Raúl; Camarero, Jesus Julio; Gutiérrez, Emilia; González Rouco, Fidel; Gazol, Antonio; Sangüesa-Barreda, Gabriel; Andreu-Hayles, Laia; Linares, Juan Carlos; Seftigen, Kristina

    2017-07-01

    Growth models can be used to assess forest vulnerability to climate warming. If global warming amplifies water deficit in drought-prone areas, tree populations located at the driest and southernmost distribution limits (rear-edges) should be particularly threatened. Here, we address these statements by analyzing and projecting growth responses to climate of three major tree species (silver fir, Abies alba; Scots pine, Pinus sylvestris; and mountain pine, Pinus uncinata) in mountainous areas of NE Spain. This region is subjected to Mediterranean continental conditions, it encompasses wide climatic, topographic and environmental gradients, and, more importantly, it includes rear-edges of the continuous distributions of these tree species. We used tree-ring width data from a network of 110 forests in combination with the process-based Vaganov-Shashkin-Lite growth model and climate-growth analyses to forecast changes in tree growth during the 21st century. Climatic projections were based on four ensembles CO 2 emission scenarios. Warm and dry conditions during the growing season constrain silver fir and Scots pine growth, particularly at the species rear-edge. By contrast, growth of high-elevation mountain pine forests is enhanced by climate warming. The emission scenario (RCP 8.5) corresponding to the most pronounced warming (+1.4 to 4.8 °C) forecasted mean growth reductions of -10.7% and -16.4% in silver fir and Scots pine, respectively, after 2050. This indicates that rising temperatures could amplify drought stress and thus constrain the growth of silver fir and Scots pine rear-edge populations growing at xeric sites. Contrastingly, mountain pine growth is expected to increase by +12.5% due to a longer and warmer growing season. The projections of growth reduction in silver fir and Scots pine portend dieback and a contraction of their species distribution areas through potential local extinctions of the most vulnerable driest rear-edge stands. Our modeling

  6. Development of female medfly attractants to support the sterile insect technique: experiments conducted in Madeira, Portugal

    International Nuclear Information System (INIS)

    Pereira, R.

    1999-01-01

    With the availability of genetic sexing strains of Mediterranean fruit fly, Ceratitis capitata (Wied.), it is possible to release only sterile males in SIT programs. The availability of a new female medfly attractant can reduce labor costs because program progress can be monitored by trapping females instead of the usual male trapping with its labor intensive identification of sterile and wild males. Three Madeira studies evaluated new female attractants; ammonium acetate, putrescine and trimethylamine. One study was carried out in the same area during two different periods of 1996 (8 June to 27 July and 12 October to 30 November). A second study was conducted between 24 May to 05 July, 1997, in two different areas at the same altitude. One area had a wild fly population (sex ratio 1: 1) and the other was in an area where sterile males were released (sex ratio > 9: 1). The third study, conducted from 18 October to 29 November, 1997, compared wild fly captures at low elevations (80 m) with those at high elevations (700 m). The first study showed that the inclusion of the attractant trimethylamine significantly increased the wild female medfly. The percentage of medfly females in the traps with the two and the three attractants (FA-2 and FA-3) was more than 70%. In the second and third studies, the dry traps were more effective than wet traps in capturing wild medfly females. In areas with only wild females, the percentage of females captured was more than 62%. In areas where sterile males were released, the percentage of females captured was between 12% and 19%. In conclusion, the new attractants captured high percentages of females and, when combined with medfly genetic sexing strains, can reduce program costs significantly. (author)

  7. LABORATORY STUDIES ON THE EFFECTS OF FIVE ADULT DIETS ON SOME BIOLOGICAL ASPECTS OF NORMAL AND GAMMA IRRADIATED ADULT MEDITERRANEAN FRUIT FLY, CERATITIS CAPITATA (WIED.)

    International Nuclear Information System (INIS)

    EL-AKHDAR, E.A.H.

    2008-01-01

    To improve the sterile insect technique for controlling the Mediterranean fruit fly, Ceratitis capitata (Wied.), experiments were carried out to test the effect of four new adult protein sources on the insect vitality. Different yeasts consisting of almost the same nutritive components but differ in the quantity of protein were mixed with sugar as carbohydrate sources (2:3) and compared to the standard adult diet (enzymatic yeast hydrolysate : sugar, 1:3). Adults reared on each diet were evaluated biologically for their response to gamma radiation (90 Gy). The weight and size of the produced pupae from parents fed on the tested diets, percent of adult emergence, sex ratio, adults survival, egg hatchability and male mating competitiveness value (C.V.) for the following generations were taken as monitors for the insect vitality. The results showed that adult male and female survival for 5, 10 and 15 days from emergence, percent egg hatchability and male mating competitiveness value (C.V.) showed no sharp differences between three tested diets D3(Af), D4(YE300) and D5(YE00) as compared to the standard diet D1(YH, enzymatic yeast hydrolysate : sugar, 1:3) for parents and F1 progeny. However, when the second tested diet D2(Ay150) was used, the results showed a significant decreases in most of the tested biological aspects, especially in the male mating competitiveness value (C.V.), which is considered the most important monitor for male insect vitality

  8. Snow hydrology in Mediterranean mountain regions: A review

    Science.gov (United States)

    Fayad, Abbas; Gascoin, Simon; Faour, Ghaleb; López-Moreno, Juan Ignacio; Drapeau, Laurent; Page, Michel Le; Escadafal, Richard

    2017-08-01

    is suitable for hydrological applications. Further advances in our understanding of the snow processes in Mediterranean snow-dominated basins will be achieved by finer and more accurate representation of the climate forcing. While the theory on the snowpack energy and mass balance is now well established, the connections between the snow cover and the water resources involve complex interactions with the sub-surface processes, which demand future investigation.

  9. Sterile Endophthalmitis after Intravitreal Injections

    Directory of Open Access Journals (Sweden)

    Joaquín Marticorena

    2012-01-01

    Full Text Available Sterile endophthalmitis appears as an infrequent complication of intravitreal injections and seems to develop mainly in the context of the off-label use of drugs that have not been conceived for intravitreous administration. The aetiology of sterile endophthalmitis, independently of the administered drug, remains uncertain and a multifactorial origin cannot be discarded. Sterile inflammation secondary both to intravitreal triamcinolone acetonide and to intravitreal bevacizumab share many characteristics such as the acute and painless vision loss present in the big majority of the cases. Dense vitreous opacity is a common factor, while anterior segment inflammation appears to be mild to moderate. In eyes with sterile endophthalmitis, visual acuity improves progressively as the intraocular inflammation reduces without any specific treatment. If by any chance the ophthalmologist is not convinced by the sterile origin of the inflammation, this complication must be treated as an acute endophthalmitis because of the devastating visual prognosis of this intraocular infection in the absence of therapy.

  10. 21 CFR 522.1862 - Sterile pralidoxime chloride.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sterile pralidoxime chloride. 522.1862 Section 522....1862 Sterile pralidoxime chloride. (a) Chemical name. 2-Formyl-1-methylpyridinium chloride oxime. (b) Specifications. Sterile pralidoxime chloride is packaged in vials. Each vial contains 1 gram of sterile...

  11. Food packaging and radiation sterilization

    International Nuclear Information System (INIS)

    Kawamura, Yoko

    1998-01-01

    Radiation sterilization has several merits that it is a positively effective sterilization method, it can be used to sterilize low heat-resistant containers and high gas barrier films, and there is no possibility of residual chemicals being left in the packages. It has been commercially used in 'Bag in a Box' and some food containers. The γ ray and an electron beam are commonly used in radiation sterilization. The γ ray can sterilize large size containers and containers with complex shapes or sealed containers due to its strong transmission capability. However, since the equipment tends to be large and expensive, it is generally used in off production lines. On the other hand, it is possible to install and electron beam system on food production lines since the food can be processed in a short time due to its high beam coefficient and its ease of maintenance, even though an electron beam has limited usage such as sterilizing relatively thin materials and surface sterilization due to the weak transmission. A typical sterilization dose is approximately 10-30 kGy. Direct effects impacting packaging materials, particularly plastics, include scission of polymer links, cross-linkage between polymers, and generating radiolysis products such as hydrogen, methane, aliphatic hydrocarbons, etc. Furthermore, under the existence of oxygen, the oxygen radicals generated by the radiation will oxidize and peroxidize polymer chains and will generate alcohol and carbonyl groups, which shear polymer links, and generate oxygen containing low molecular compounds. As a result, degradation of physical strength such as elongation and seal strength, generating foreign odor, and an increase in global migration values shown in an elution test are sometimes evident. The food packages have different shapes, materials, additives, number of microorganisms and purpose. Therefor the effects of radiation, the optimum dose and so on must be investigated on the individual package. (J.P.N.)

  12. Seeking sterile neutrinos in Finslerian cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Deng [Nankai University, Theoretical Physics Division, Chern Institute of Mathematics, Tianjin (China); Meng, Xin-He [Nankai University, Department of Physics, Tianjin (China)

    2017-11-15

    For the first time, to search for sterile neutrinos in the framework of Finler geometry, we constrain four cosmological models using the most stringent constraint we can provide so far. We find that the Finslerian massless sterile neutrino model can, respectively, give a better cosmological fit to data and alleviate the current H{sub 0} tension more effectively than the other three models. For the Finslerian massless sterile neutrino model, we obtain the constraint N{sub eff} = 3.237{sup +0.092}{sub -0.185}, which is consistent with ΔN{sub eff} > 0 at the 1.03σ confidence level (CL). This gives a very weak hint of massless sterile neutrinos and may imply the non-existence of massless sterile neutrinos in the Finslerian cosmological setting. For the Finslerian massive sterile neutrino model, we obtain the constraints N{sub eff} = 3.143{sup +0.064}{sub -0.066}, which favors ΔN{sub eff} > 0 at the 1.47σ CL, and m{sub ν,sterile}{sup eff} < 0.121 eV at the 2σ CL which is much tighter than the Planck results. This very tight restriction appears to indicate the massive sterile neutrinos are also non-existent in the Finslerian scenarios. Consequently, one may conclude that the sterile neutrinos are possibly non-existent in the Finslerian universe. Our results are compatible with the recent results of the neutrino oscillation experiments implemented by the Daya Bay and MINOS collaborations and the cosmic ray one carried out by the IceCube collaboration. (orig.)

  13. The νMSM, dark matter and neutrino masses

    International Nuclear Information System (INIS)

    Asaka, Takehiko; Blanchet, Steve; Shaposhnikov, Mikhail

    2005-01-01

    We investigate an extension of the Minimal Standard Model by right-handed neutrinos (the νMSM) to incorporate neutrino masses consistent with oscillation experiments. Within this theory, the only candidates for dark matter particles are sterile right-handed neutrinos with masses of a few keV. Requiring that these neutrinos explain entirely the (warm) dark matter, we find that their number is at least three. We show that, in the minimal choice of three sterile neutrinos, the mass of the lightest active neutrino is smaller than O(10 -5 ) eV, which excludes the degenerate mass spectra of three active neutrinos and fixes the absolute mass scale of the other two active neutrinos

  14. Rats socially-reared and full fed learned an autoshaping task, showing less levels of fear-like behaviour than fasted or singly-reared rats.

    Science.gov (United States)

    Molina-Hernández, Miguel; Téllez-Alcántara, N Patricia

    2004-07-01

    During the learning of instrumental tasks, rats are usually fasted to increase reinforced learning. However, fasting produces several undesirable side effects. The aim of this study was to test the hypothesis that control rats, i.e. full-fed and group-reared rats, will learn an autoshaping task to the same level as fasted or singly-reared rats. The interaction between fasting and single-rearing of rats was also tested. Results showed that control rats and fasted rats acquired the autoshaping task similarly, independently of rearing condition or gender. However, fasted or singly-reared rats produced fear-like behaviour, since male rats group-reared and fasted (85% body/wt, P autoshaping task to the same level as fasted or singly-reared rats. However, fasting or single-rearing produced fear-like behaviour. Thus, the training of control rats in autoshaping tasks may be an option that improves animal welfare.

  15. Documentation requirements for radiation sterilization

    DEFF Research Database (Denmark)

    Miller, A.

    1995-01-01

    Several standards are recently approved or are under development by the standard organizations ISO and CEN in the field of radiation sterilization. Particularly in Europe these standards define new requirements on some issues and on other issues they emphasize the necessary documentation for appr......Several standards are recently approved or are under development by the standard organizations ISO and CEN in the field of radiation sterilization. Particularly in Europe these standards define new requirements on some issues and on other issues they emphasize the necessary documentation...... for approval of radiation sterilized products. The impact of these standards on the radiation sterilization is discussed, with special attention given to a few special issues, mainly traceability and uncertainty of measurement results....

  16. Temperature sensitive lethal factors and puparial colour sex separation mechanisms in the Mediterranean fruit fly, Ceratitis capitata (Wied.)

    International Nuclear Information System (INIS)

    Busch-Petersen, E.

    1990-01-01

    A programme to develop genetic sexing mechanisms in the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann), was initiated at the IAEA Laboratories, Seibersdorf, in 1983. Because of the potential benefits arising from the elimination of females early in the developmental cycle, combined with the anticipated relative ease of inducing temperature sensitive lethal (tsl) factors, it was decided to attempt to induce and isolate tsl factors active in the egg or early larval stages. Initially, five recombination suppressor (RS) strains were isolated. The degree of recombination suppression ranged from 77.6% to 99.1%. The viability of each of the five RS strains was assessed and RS 30/55 was selected as the most suitable strain. Ethyl methanesulphonate (EMS) was used to induce the tsl factors, by feeding two-day old adult males with a suspension of EMS in a 10% solution of sugar in the drinking water supply. Temperature tolerance tests indicated a discriminating temperature of 32 deg. C when isolating tsl factors active in the egg stage and 35 deg. C when isolating such factors in the early larval stage. A total of 39 and 22 tsl factors have been isolated in the two stages, respectively. However, none has yet proved stable. Induction of tsl factors with a reduced dose of EMS is now being attempted. An alternative genetic sexing programme was initiated in 1985, based on the use of pupal colour dimorphisms. Previously, a genetic sexing strain, T:Y(wp + )101, based on a white female/brown male puparial colour dimorphism, had twice been assessed for stability under mass rearing conditions. In both cases the sexual colour dimorphism disintegrated immediately. Another similarly dimorphic strain, T:Y(wp + )30C, was developed. This strain remained stable for seven generations of mass rearing, after which it started to disintegrate. Disintegration of this strain was probably caused by accidental contamination by wild type medflies. 34 refs, 1 fig., 1 tab

  17. Plasma Sterilization: New Epoch in Medical Textiles

    Science.gov (United States)

    Senthilkumar, P.; Arun, N.; Vigneswaran, C.

    2015-04-01

    Clothing is perceived to be second skin to the human body since it is in close contact with the human skin most of the times. In hospitals, use of textile materials in different forms and sterilization of these materials is an essential requirement for preventing spread of germs. The need for appropriate disinfection and sterilization techniques is of paramount importance. There has been a continuous demand for novel sterilization techniques appropriate for use on various textile materials as the existing sterilization techniques suffer from various technical and economical drawbacks. Plasma sterilization is the alternative method, which is friendlier and more effective on the wide spectrum of prokaryotic and eukaryotic microorganisms. Basically, the main inactivation factors for cells exposed to plasma are heat, UV radiation and various reactive species. Plasma exposure can kill micro-organisms on a surface in addition to removing adsorbed monolayer of surface contaminants. Advantages of plasma surface treatment are removal of contaminants from the surface, change in the surface energy and sterilization of the surface. Plasma sterilization aims to kill and/or remove all micro-organisms which may cause infection of humans or animals, or which can cause spoilage of foods or other goods. This review paper emphasizes necessity for sterilization, essentials of sterilization, mechanism of plasma sterilization and the parameters influencing it.

  18. Sterilization can change properties of bioceramics

    International Nuclear Information System (INIS)

    Willmann, G.

    2003-01-01

    Bioceramics made of bioinert alumina or zirconia and bioactive hydroxyapatite are well established implant materials. Implants have to be cleaned and sterilized. When sterilized some bioceramics change their color. This may effect their properties. No decrease of mechanical strength is observed when sterilizing alumina and the novel ceramic biocomposite AMC (Alumina Matrix Composite) with steam or Co 60 Gamma irradiation. When sterilizing Y-TZP zirconia with steam a decrease of strength is observed. (Abstract Copyright [2003], Wiley Periodicals, Inc.) [de

  19. International Standards for Radiation Sterilization of Medical Devices

    International Nuclear Information System (INIS)

    Miller, A.

    2007-01-01

    For a terminally sterilized medical device to be designated '' STERILE '', probability of finding the viable micro-organisms in the device shall be equal to or less than 1 x 10 -6 (EN 556-1:2001: Sterilization of medical devices - Requirements for medical devices to be designated '' STERILE '' - Part 1: Requirements for terminally sterilized medical devices). Author presents the main legal aspects of the international standards for radiation sterilization of medical devices

  20. Delivery of Nucleic Acids through Embryo Microinjection in the Worldwide Agricultural Pest Insect, Ceratitis capitata.

    Science.gov (United States)

    Gabrieli, Paolo; Scolari, Francesca

    2016-10-01

    The Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is a pest species with extremely high agricultural relevance. This is due to its reproductive behavior: females damage the external surface of fruits and vegetables when they lay eggs and the hatched larvae feed on their pulp. Wild C. capitata populations are traditionally controlled through insecticide spraying and/or eco-friendly approaches, the most successful being the Sterile Insect Technique (SIT). The SIT relies on mass-rearing, radiation-based sterilization and field release of males that retain their capacity to mate but are not able to generate fertile progeny. The advent and the subsequent rapid development of biotechnological tools, together with the availability of the medfly genome sequence, has greatly boosted our understanding of the biology of this species. This favored the proliferation of new strategies for genome manipulation, which can be applied to population control. In this context, embryo microinjection plays a dual role in expanding the toolbox for medfly control. The ability to interfere with the function of genes that regulate key biological processes, indeed, expands our understanding of the molecular machinery underlying medfly invasiveness. Furthermore, the ability to achieve germ-line transformation facilitates the production of multiple transgenic strains that can be tested for future field applications in novel SIT settings. Indeed, genetic manipulation can be used to confer desirable traits that can, for example, be used to monitor sterile male performance in the field, or that can result in early life-stage lethality. Here we describe a method to microinject nucleic acids into medfly embryos to achieve these two main goals.

  1. A lower limit on the dark particle mass from dSphs

    Energy Technology Data Exchange (ETDEWEB)

    Angus, G.W., E-mail: angus@ph.unito.it [Dipartimento di Fisica Generale ' ' Amedeo Avogadro' ' , Università degli Studi di Torino, Via P. Giuria 1, I-10125, Torino (Italy)

    2010-03-01

    We use dwarf spheroidal galaxies as a tool to attempt to put precise lower limits on the mass of the dark matter particle, assuming it is a sterile neutrino. We begin by making cored dark halo fits to the line of sight velocity dispersions as a function of projected radius (taken from Walker et al. 2007) for six of the Milky Way's dwarf spheroidal galaxies. We test Osipkov-Merritt velocity anisotropy profiles, but find that no benefit is gained over constant velocity anisotropy. In contrast to previous attempts, we do not assume any relation between the stellar velocity dispersions and the dark matter ones, but instead we solve directly for the sterile neutrino velocity dispersion at all radii by using the equation of state for a partially degenerate neutrino gas (which ensures hydrostatic equilibrium of the sterile neutrino halo). This yields a 1:1 relation between the sterile neutrino density profile and the velocity dispersion profile, and therefore gives us an accurate estimate of the Tremaine-Gunn limit at all radii. By varying the sterile neutrino particle mass, we locate the minimum mass for all six dwarf spheroidals such that the Tremaine-Gunn limit is not exceeded at any radius (in particular at the centre). We find sizeable differences between the ranges of feasible sterile neutrino particle mass for each dwarf, but interestingly there exists a small range 270-280eV which is consistent with all dSphs at the 1-σ level.

  2. A lower limit on the dark particle mass from dSphs

    International Nuclear Information System (INIS)

    Angus, G.W.

    2010-01-01

    We use dwarf spheroidal galaxies as a tool to attempt to put precise lower limits on the mass of the dark matter particle, assuming it is a sterile neutrino. We begin by making cored dark halo fits to the line of sight velocity dispersions as a function of projected radius (taken from Walker et al. 2007) for six of the Milky Way's dwarf spheroidal galaxies. We test Osipkov-Merritt velocity anisotropy profiles, but find that no benefit is gained over constant velocity anisotropy. In contrast to previous attempts, we do not assume any relation between the stellar velocity dispersions and the dark matter ones, but instead we solve directly for the sterile neutrino velocity dispersion at all radii by using the equation of state for a partially degenerate neutrino gas (which ensures hydrostatic equilibrium of the sterile neutrino halo). This yields a 1:1 relation between the sterile neutrino density profile and the velocity dispersion profile, and therefore gives us an accurate estimate of the Tremaine-Gunn limit at all radii. By varying the sterile neutrino particle mass, we locate the minimum mass for all six dwarf spheroidals such that the Tremaine-Gunn limit is not exceeded at any radius (in particular at the centre). We find sizeable differences between the ranges of feasible sterile neutrino particle mass for each dwarf, but interestingly there exists a small range 270-280eV which is consistent with all dSphs at the 1-σ level

  3. Birth planning and sterilization in China.

    Science.gov (United States)

    Short, S E; Linmao, M; Wentao, Y

    2000-11-01

    Sterilization is the most prevalent method of contraception in China. Approximately half of all women of reproductive age report that they or their husbands are sterilized. Using data from the China Health and Nutrition Survey we describe patterns of sterilization in eight Chinese provinces. With a discrete-time event history model we investigate the link between characteristics of local birth planning policy and the risk of sterilization. After controlling for parity, the risk of sterilization is highest in communities where birth planning policy is least strong as measured by exceptions to the one-child policy. These results suggest that couples with more flexibility in family building may have less control over contraceptive method use. Other factors affecting the risk of sterilization are a woman's age, parity, and whether or not she has a son. Our results emphasize the importance of taking into account multiple dimensions of reproductive behaviour when assessing one-child policy changes.

  4. Construction of a male sterility system for hybrid rice breeding and seed production using a nuclear male sterility gene

    OpenAIRE

    Chang, Zhenyi; Chen, Zhufeng; Wang, Na; Xie, Gang; Lu, Jiawei; Yan, Wei; Zhou, Junli; Tang, Xiaoyan; Deng, Xing Wang

    2016-01-01

    Nuclear male sterility is common in flowering plants, but its application in hybrid breeding and seed production is limited because of the inability to propagate a pure male sterile line for commercial hybrid seed production. Here, we characterized a rice nuclear gene essential for sporophytic male fertility and constructed a male sterility system that can propagate the pure male sterile seeds on a large scale. This system is fundamentally advantageous over the current cytoplasmic male steril...

  5. Studies on control of yellow stem borer, Tryporyza incertulas, a serious pest of paddy. Part of a coordinated programme on the use of pest management with emphasis on rice insects

    International Nuclear Information System (INIS)

    Rahalkar, G.W.

    1982-03-01

    Egg parasitism is the chief biotic factor regulating paddy stem borer populations. However, effective suppression of the borer through their natural enemies is not evident in practice. Studies were undertaken to evaluate the feasibility of releasing sterile yellow stem borer females into the field to increase host egg densities as these females would lay nonviable eggs. (a) Paddy fields were surveyed for the incidence of egg parasitism. (b) Attempts were made to rear yellow stem borer larvae on cut stem pieces of field grown rice plants. (c) Trichogramma japonicum, the natural egg parasite of the stem borer was reared in the laboratory using eggs of Corcyra cephalonica and Ephestia cautella as alternate host material. Mass rearing of yellow stem borer larvae on paddy plants grown under laboratory conditions does not appear practically feasible. Borer larvae reared on cut stem pieces with intact roots did not yield satisfactory adults as far as their reproductive behaviour was concerned. Though some of the dietary compositions contained natural host material, they failed to support the larval establishment. Probably some highly specific phagostimulants need to be incorporated in the diets. T. japonicum could be reared on radiation killed Ephestia eggs. The female parasite was unable to discriminate between eggs laid by radiation sterilized host females and those laid by normal ones

  6. Distinguishing Dirac/Majorana sterile neutrinos at the LHC

    International Nuclear Information System (INIS)

    Dib, Claudio O.; Zhang, Jue

    2016-06-01

    We study the purely leptonic decays of W ± → e ± e ± μ -+ ν and μ ± μ ± e -+ ν produced at the LHC, induced by sterile neutrinos with mass m N below M W in the intermediate state. Since the final state neutrino escapes detection, one cannot tell whether this process violates lepton number, what would indicate a Majorana character for the intermediate sterile neutrino. Our study shows that when the sterile neutrino mixings with electrons and muons are different enough, one can still discriminate between the Dirac and Majorana character of this intermediate neutrino by simply counting and comparing the above decay rates. After performing collider simulations and statistical analysis, we find that at the 14 TeV LHC with an integrated luminosity of 3000 fb -1 , for two benchmark scenarios m N =20 GeV and 50 GeV, at least a 3σ level of exclusion on the Dirac case can be achieved for disparities as mild as e.g. vertical stroke U Ne vertical stroke 2 <0.7 vertical stroke U Nμ vertical stroke 2 or vertical stroke U Nμ vertical stroke 2 <0.7 vertical stroke U Ne vertical stroke 2 , provided that vertical stroke U Ne vertical stroke 2 , vertical stroke U Nμ vertical stroke 2 are both above ∝2 x 10 -6 .

  7. Validation of radiation sterilization process

    International Nuclear Information System (INIS)

    Kaluska, I.

    2007-01-01

    The standards for quality management systems recognize that, for certain processes used in manufacturing, the effectiveness of the process cannot be fully verified by subsequent inspection and testing of the product. Sterilization is an example of such a process. For this reason, sterilization processes are validated for use, the performance of sterilization process is monitored routinely and the equipment is maintained according to ISO 13 485. Different aspects of this norm are presented

  8. The male gametophytic sterility. 1 - Gametic sterilities and deletions in petunia

    International Nuclear Information System (INIS)

    Cornu, A.; Maizonnier, D.

    1982-01-01

    Terminal deletions induced by ionizing radiations in Petunia are not sexually transmitted. Cytogenetic study of plants with a heterozygous deletion and their progenies shows that this lack of transmission is accompanied by a gametic semi-sterility due to the fact that gametes carrying the deleted chromosome are not viable. The interest of such a male sterility with a gametophytic determinism for the study of sporophyte-gametophyte relationships is underlined [fr

  9. Radiosterilization or sterilization by steam. Procedures for sterilization of spices

    International Nuclear Information System (INIS)

    Warmbold, J.

    1994-01-01

    The article compares two different methods for the sterilization of spices, namely radiosterilization and sterilization with steam. The first method applies ionizing radiation which can alter the chemical composition of the products. Tests have shown, however, that radiation doses up to 10 kGy will not induce the formation of carcinogenic agents in the foodstuffs, or of toxic substances, and thus are a wholesome method of preservation. Any modifications of taste, color or smell, or loss of vitamins, can be avoided by proper dose control and standard irradiation conditions. Sterilization by steam is a method achieving substantial suppression of the formation of germs, aerobic spores, yeasts, mould, and gramnegative germs, while preserving in most cases the essential oils. It may result in sensoric alterations, i.e affect the color, smell or taste, but in general the spices thus treated preserved their characteristic properties. The method is a good alternative to radiosterilization. The article adds some concluding information on mandatory labelling of irradiated food imported from third countries

  10. Rearing of Lymnaea columella (Say, 1817, intermediate host of Fasciola hepatica (Linnaeus, 1758

    Directory of Open Access Journals (Sweden)

    Souza Cecília Pereira de

    2000-01-01

    Full Text Available The intermediate host of Fasciola hepatica, Lymnaea columella, collected in Belo Horizonte, Minas Gerais, Brazil, was reared in our laboratory. The aim of the current study was to standardize a rearing and maintenance technique. Two kinds of diet were tested: fresh lettuce (A and rodent ration + 10% CaCO3 plus fresh lettuce (B. The age for the beginning of oviposition ranged from 27 to 57 days. Ten days after oviposition at 24.7°C, 100% eclosion occurred. The complete life cycle varied from 37 to 67 days. The average numbers of eggs per egg mass were 26.3 and 31.1 with diets (A and (B, respectively. The lettuce and ration fed snails presented a increased growth although the difference was not statistically significant (p > 0.05. The mortality rate varied from 40 to 64% after 90 days. The maximum longevity was 183 days, 21.5 mm length and 11 mm wide. The methodology to mass breed and maintain these snails was found to be suitable in the laboratory

  11. Mediterranean diet score and left ventricular structure and function: the Multi-Ethnic Study of Atherosclerosis12

    Science.gov (United States)

    Levitan, Emily B; Ahmed, Ali; Arnett, Donna K; Polak, Joseph F; Hundley, W Gregory; Bluemke, David A; Heckbert, Susan R; Jacobs, David R; Nettleton, Jennifer A

    2016-01-01

    Background: Data are limited on the relation between dietary patterns and left ventricular (LV) structure and function. Objective: We examined cross-sectional associations of a diet-score assessment of a Mediterranean dietary pattern with LV mass, volume, mass-to-volume ratio, stroke volume, and ejection fraction. Design: We measured LV variables with the use of cardiac MRI in 4497 participants in the Multi-Ethnic Study of Atherosclerosis study who were aged 45–84 y and without clinical cardiovascular disease. We calculated a Mediterranean diet score from intakes of fruit, vegetables, nuts, legumes, whole grains, fish, red meat, the monounsaturated fat:saturated fat ratio, and alcohol that were self-reported with the use of a food-frequency questionnaire. We used linear regression with adjustment for body size, physical activity, and cardiovascular disease risk factors to model associations and assess the shape of these associations (linear or quadratic). Results: The Mediterranean diet score had a slight U-shaped association with LV mass (adjusted means: 146, 145, 146, and 147 g across quartiles of diet score, respectively; P-quadratic trend = 0.04). The score was linearly associated with LV volume, stroke volume, and ejection fraction: for each +1-U difference in score, LV volume was 0.4 mL higher (95% CI: 0.0, 0.8 mL higher), the stroke volume was 0.5 mL higher (95% CI: 0.2, 0.8 mL higher), and the ejection fraction was 0.2 percentage points higher (95% CI: 0.1, 0.3 percentage points higher). The score was not associated with the mass-to-volume ratio. Conclusions: A higher Mediterranean diet score is cross-sectionally associated with a higher LV mass, which is balanced by a higher LV volume as well as a higher ejection fraction and stroke volume. Participants in this healthy, multiethnic sample whose dietary patterns most closely conformed to a Mediterranean-type pattern had a modestly better LV structure and function than did participants with less–Mediterranean

  12. [Legal statutes on sterilization].

    Science.gov (United States)

    Zupancic, K

    1980-01-01

    Sterilization in Yugoslavia is no population policy measure. Decision about the birth of children is free, a private problem of any individual, a basic right guaranteed by the Constitution. However, according to certain laws in Slovenia and Croatia, sterilization is allowed as a family planning method in persons over 35 year old. Only exceptionally can sterilization be applied in persons younger than 35 years: according to the Slovenian law, in cases when a person lacks the capacity of reasoning and also when there are medical indications, and according to the Croatian law, when there are medical and eugenic reasons (if the child is supposed to be born with negative congenital properties).

  13. Electron sterilization validation techniques using the controlled depth of sterilization process

    International Nuclear Information System (INIS)

    Cleghorn, D.A.; Nablo, S.V.

    1990-01-01

    Many pharmaceutical products, especially parenteral drugs, cannot be sterilized with gamma rays or high energy electrons due to the concomitant product degradation. In view of the well-controlled electron energy spectrum available in modern electron processors, it is practical to deliver sterilizing doses over depths considerably less than those defining the thickness of blister-pack constructions or pharmaceutical containers. Because bremsstrahlung and X-ray production are minimized at these low electron energies and in these low Z materials, very high electron: penetrating X-ray dose ratios are possible for the application of the technique. Thin film dosimetric techniques have been developed utilizing radiochromic film in the 10-60 g/m 2 range for determining the surface dose distribution in occluded surface areas where direct electron illumination is not possible. Procedures for validation of the process using dried spore inoculum on the product as well as in good geometry are employed to determine the process lethality and its dependence on product surface geometry. Applications of the process to labile pharmaceuticals in glass and polystyrene syringes are reviewed. It has been applied to the sterilization of commercial sterile products since 1987, and the advantages and the natural limitations of the technique are discussed. (author)

  14. Captive-rearing piping plovers: Developing techniques to augment wild populations

    Science.gov (United States)

    Powell, A.N.; Cuthbert, F.J.; Wemmer, L.C.; Doolittle, A.W.; Feirer, S.T.

    1997-01-01

    Techniques for captive-rearing and releasing piping plovers (Charadrius melodus) were developed using a surrogate species, killdeer (Charadrius vociferus). We compared captive-and parent-reared killdeer, and parent-reared piping plovers and determined that growth and behavior were similar. After surrogate trials determined that captive-rearing was feasible, we used the same methods to raise piping plover chicks from salvaged eggs. For captive-reared chick of both species, survival to fledging was higher than and behaviors similar to parent-reared chicks in the wild. Rearing techniques were fine-tuned, and ten piping plover fledglings were released to the wild. Based on our results, we developed recommendations for captive-rearing piping plovers using salvaged eggs to enhance productivity of small populations. ?? 1997 Wiley-Liss, Inc.

  15. Mediterranean diet

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000110.htm Mediterranean diet To use the sharing features on this page, ... and other health problems. How to Follow the Diet The Mediterranean diet is based on: Plant-based ...

  16. Male sterility in chestnuts

    International Nuclear Information System (INIS)

    Omura, Mitsuo; Akihama, Tomoya

    1982-01-01

    A tentative plan was proposed for chestnuts based on their pollination system, male sterility and restoration. The studies on the male sterility of 1,063 cultivars and clones suggested that there were three types of male sterility. The first type (S-1) was characterized by antherless florets. In the second type (S-2), the catkins fell before anthesis, and the third type (S-3) appeared to develop normally in gross floral morphology, but the pollen grains were abnormal in shape and did not have germinating power. In an interspecific hybrid clone CS which belonged to S-1, fertility was restored in an open pollinated progeny. The use of CS and CSO-3 with its restored fertility, permitted the planning of breeding the chestnut hybrid cultivars propagated by seeds. The inbred clones with either male sterility or restorer genes are first bred mainly by back crossing with parents with favorable pollen. The clones are selected individually for early bearing, wasp and disease resistance, and restoration. Then, the hybrid seedling lines between male sterile and restorer inbreds are evaluated for homogenity in nut characters and tree habits. Next, the hybrid seedling lines selected will be examined for crop yield, vigor and cross compatibility. The superior seedling lines are finally selected, and the parental inbreds are grafted to be propagated for seed production orchards. (Kaihara, S.)

  17. Gamma sterilization of disposable medical products (DMP's)

    International Nuclear Information System (INIS)

    Brinston, R.M.

    1990-01-01

    Ten million cubic meters (361 million cubic feet) of disposable medical products (DMP) and related health care items are estimated to be sterilized in the world. In this paper, current conditions and perspectives of gamma sterilization is discussed in comparison with ethylene oxide gas and electron beams. Of the total sterilization estimates for DMP, 2.8 million cubic meters (99 million cubic feet) are sterilized with gamma radiation, with a market share of 27%. Gamma radiation is becoming increased from both general market growth and the introduction of new products, as well as the conversion of product from ethylene oxide gas to cobalt-60. Regulatory pressures, legal considerations, and increasing publicity surrounding ethylene oxide usage are encouraging manufactures to switch to gamma radiation. Gamma's performance features include: no temperature change during the sterilization, high penetration, even through hermetically sealed packages, no residues, and no post-sterilization treatment or quarantine period. Gamma sterilization is economically beneficial in large volumes of product. Cost saving to the end user of gamma sterilization has meant lower minimum dose levels than 25 KGy. Despite of an increasingly accepted gamma radiation, there are still four factors to be considered, including cobalt-60 availability, price, transportation, and disposal. The price of cobalt-60 is based on neutron cost. In the future, cobalt-60 price is expected to be flat and enables gamma processing to become even more competitive with other sterilization methods. Gamma radiation using cobalt-60 has been proven as a safe, effective, and cost-competitive sterilization method for treating DMP and related health care items. It's wide use and many processing advantages will continue to make it a preferred sterilization method. (N.K.)

  18. Probabilistic model for sterilization of food

    International Nuclear Information System (INIS)

    Chepurko, V.V.; Malinovskij, O.V.

    1986-01-01

    The probabilistic model for radiation sterilization is proposed based on the followng suppositions: (1) initial contamination of a volume unit of the sterilized product m is described by the distribution of the probabilities q(m), (2) inactivation of the population from m of microorganisms is approximated by Bernoulli test scheme, and (3) contamination of unit of the sterilized product is independent. The possibility of approximation q(m) by Poisson distribution is demonstrated. The diagrams are presented permitting to evaluate the dose which provides the defined reliability of sterilization of food for chicken-gnotobionts

  19. Genetic versus rearing-environment effects on phenotype: hatchery and natural rearing effects on hatchery- and wild-born coho salmon.

    Directory of Open Access Journals (Sweden)

    Cedar M Chittenden

    Full Text Available With the current trends in climate and fisheries, well-designed mitigative strategies for conserving fish stocks may become increasingly necessary. The poor post-release survival of hatchery-reared Pacific salmon indicates that salmon enhancement programs require assessment. The objective of this study was to determine the relative roles that genotype and rearing environment play in the phenotypic expression of young salmon, including their survival, growth, physiology, swimming endurance, predator avoidance and migratory behaviour. Wild- and hatchery-born coho salmon adults (Oncorhynchus kisutch returning to the Chehalis River in British Columbia, Canada, were crossed to create pure hatchery, pure wild, and hybrid offspring. A proportion of the progeny from each cross was reared in a traditional hatchery environment, whereas the remaining fry were reared naturally in a contained side channel. The resulting phenotypic differences between replicates, between rearing environments, and between cross types were compared. While there were few phenotypic differences noted between genetic groups reared in the same habitat, rearing environment played a significant role in smolt size, survival, swimming endurance, predator avoidance and migratory behaviour. The lack of any observed genetic differences between wild- and hatchery-born salmon may be due to the long-term mixing of these genotypes from hatchery introgression into wild populations, or conversely, due to strong selection in nature--capable of maintaining highly fit genotypes whether or not fish have experienced part of their life history under cultured conditions.

  20. Sterile neutrino, hidden dark matter and their cosmological signatures

    International Nuclear Information System (INIS)

    Das, Subinoy

    2012-01-01

    Though thermal dark matter has been the central idea behind the dark matter candidates, it is highly possible that dark matter of the universe is non-thermal in origin or it might be in thermal contact with some hidden or dark sector but not with standard model. Here we explore the cosmological bounds as well as the signatures on two types of non-thermal dark matter candidates. First we discuss a hidden dark matter with almost no interaction (or very feeble) with standard model particles so that it is not in thermal contact with visible sector but we assume it is thermalized with in a hidden sector due to some interaction. While encompassing the standard cold WIMP scenario, we do not require the freeze-out process to be non-relativistic. Rather, freeze-out may also occur when dark matter particles are semi-relativistic or relativistic. Especially we focus on the warm dark matter scenario in this set up and find the constraints on the warm dark matter mass, cross-section and hidden to visible sector temperature ratio which accounts for the observed dark-matter density, satisfies the Tremaine-Gunn bound on dark-matter phase space density and has a free-streaming length consistent with cosmological constraints on the matter power spectrum. Our method can also be applied to keV sterile neutrino dark matter which is not thermalized with standard model but is thermalized with in a dark sector. The second part of this proceeding focuses on an exotic dark matter candidate which arises from the existence of eV mass sterile neutrino through a late phase transition. Due to existence of a strong scalar force the light sterile states get trapped into stable degenerate micro nuggets. We find that its signature in matter power spectra is close to a warm dark matter candidate.

  1. Voluntary sterilization in Serbia: Unmet need?

    Directory of Open Access Journals (Sweden)

    Rašević Mirjana M.

    2002-01-01

    Full Text Available Is voluntary sterilization as a birth control method accepted in Serbia? This is certainly a question that is being imposed for research, regardless of the fact that voluntary sterilization is neither accessible nor promoted. Most importantly because there is no understanding in the social nor political sphere for legalization of voluntary sterilization as a form of birth control, apart from the clear necessity for this, first, step. They are: the recognition that voluntary sterilization is an efficient and safe birth control method, respectability of basic human as well as sexual and reproductive rights, spreading of sterilization as a form of birth control among population of both developed and developing countries and an epidemic diffusion of repeated induced abortions in Serbia. Thus individual recognition of the advantages of relying on voluntary sterilization, in a non-encouraging atmosphere, certainly represents one more argument to enable couples to prevent conception by sterilization. Since it was impossible to carry out a representative research among the population of men and women who are at risk for conception, an attempt was made to obtain a reply to the set question among women who decided to induce abortion. It was done out of at least two reasons. The first being that women with induced abortion in their reproductive history were the target group for voluntary sterilization. The second reason was based on the assumption that bringing a decision on induced abortion is preceded by the reconsideration of an earlier adopted strategy regarding children, giving birth and contraception and thus its rational component is revealed more and therefore more easily measurable. The research was carried out in the University Clinic of Obstetrics and Gynecology 'Narodni front' in Belgrade from January 21st o March 1st 2002, and included 296 women. By comparing the social and demographic characteristics of the female respondents, as well as

  2. SOX - Towards the detection of sterile neutrinos in Borexino. Beta spectrum modeling, Monte Carlo development and sensitivity studies for the sterile neutrino search in Borexino

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Mikko

    2016-12-15

    Several experiments have reported anomalies in the neutrino sector which might be explained by the existence of a fourth (sterile) neutrino with a squared mass difference of about 1 eV{sup 2} to the other three active neutrinos. The SOX project is part of the experimental program of the Borexino experiment and seeks for a clarification of the observed anomalies. For that purpose an artificial antineutrino source ({sup 144}Ce-{sup 144}Pr) and possibly neutrino source ({sup 51}Cr) will be deployed underneath the large low background detector Borexino. The detector provides both energy and vertex resolution to observe a possible oscillation signature within the detector volume. The calculation of the antineutrino spectrum is based on existing theoretical models and was performed within this thesis. The modeling includes several sub-leading corrections particularly such as finite size of the nucleus, screening of the atomic electrons and radiative effects. Related to this work, dedicated Monte Carlo generators have been developed to simulate the inverse beta decay reaction and the (anti)neutrino elastic scattering off electrons. Based on a profile likelihood analysis, the sensitivity to the sterile neutrino search of the SOX project was evaluated. The results obtained from this analysis confirm that the currently allowed parameter regions for sterile neutrinos can be tested at 95% confidence level. Finally, an alternative concept for the sterile neutrino search is presented which is based on a cyclotron and a Beryllium target near Borexino (Borexino+IsoDAR).

  3. SOX - Towards the detection of sterile neutrinos in Borexino. Beta spectrum modeling, Monte Carlo development and sensitivity studies for the sterile neutrino search in Borexino

    International Nuclear Information System (INIS)

    Meyer, Mikko

    2016-12-01

    Several experiments have reported anomalies in the neutrino sector which might be explained by the existence of a fourth (sterile) neutrino with a squared mass difference of about 1 eV"2 to the other three active neutrinos. The SOX project is part of the experimental program of the Borexino experiment and seeks for a clarification of the observed anomalies. For that purpose an artificial antineutrino source ("1"4"4Ce-"1"4"4Pr) and possibly neutrino source ("5"1Cr) will be deployed underneath the large low background detector Borexino. The detector provides both energy and vertex resolution to observe a possible oscillation signature within the detector volume. The calculation of the antineutrino spectrum is based on existing theoretical models and was performed within this thesis. The modeling includes several sub-leading corrections particularly such as finite size of the nucleus, screening of the atomic electrons and radiative effects. Related to this work, dedicated Monte Carlo generators have been developed to simulate the inverse beta decay reaction and the (anti)neutrino elastic scattering off electrons. Based on a profile likelihood analysis, the sensitivity to the sterile neutrino search of the SOX project was evaluated. The results obtained from this analysis confirm that the currently allowed parameter regions for sterile neutrinos can be tested at 95% confidence level. Finally, an alternative concept for the sterile neutrino search is presented which is based on a cyclotron and a Beryllium target near Borexino (Borexino+IsoDAR).

  4. Perceived parental rearing of bipolar offspring

    NARCIS (Netherlands)

    Reichart, C. G.; van der Ende, J.; Hillegers, M. H. J.; Wals, M.; Bongers, I. L.; Nolen, W. A.; Ormel, J.; Verhulst, F. C.

    Objective: To explore the impact of growing up with a parent with a bipolar disorder. First, we compared parental rearing behavior perceived by young adult offspring of bipolar parents with parental rearing behavior perceived by same aged young adults from the general population. Secondly, we

  5. Forced sterilization of women as discrimination.

    Science.gov (United States)

    Patel, Priti

    2017-01-01

    There has been a long history of subjecting marginalized women to forced and coerced sterilization. In recent years, the practice has been documented in countries in North and South America, Europe, Asia, and Africa. It has targeted women who are ethnic and racial minorities, women with disabilities, women living with HIV, and poor women. A handful of courts have issued decisions on the recent forced sterilization of marginalized women finding that such actions violate the women's rights. However, they have all failed to address the women's claims of discrimination. The failure to acknowledge that forced sterilization is at its core a violation of the prohibition of discrimination undermines efforts to eradicate the practice. It further fails to recognize that coerced and forced sterilization fundamentally seeks to deny women deemed as "unworthy" the ability to procreate. Four key principles outlined in the human rights in patient care framework highlight the importance of a finding that the prohibition of discrimination was violated in cases of forced sterilization: the need to highlight the vulnerability of marginalized populations to discrimination in health care settings; the importance of the rights of medical providers; the role of the state in addressing systemic human rights violations in health care settings; and the application of human rights to patient care. Based on these principles, it is clear that finding a violation of the prohibition of discrimination in forced sterilization cases is critical in addressing the systemic nature of the practice, acknowledging the marginalization of specific groups and effectively ending forced sterilization through addressing the underlying purpose of the practice. If litigators, non-governmental organizations and judicial officers are mindful of these principles when dealing with cases of forced sterilization, it is likely that they will be better able to eradicate forced sterilization.

  6. More than just drought: complexity of recruitment patterns in Mediterranean forests.

    Science.gov (United States)

    Granda, Elena; Escudero, Adrián; Valladares, Fernando

    2014-12-01

    Understanding community dynamics during early life stages of trees is critical for the prediction of future species composition. In Mediterranean forests drought is a major constraint for regeneration, but likely not the only factor determining the observed spatial patterns. We carried out a sowing experiment aimed at identifying main filters during seed-seedling transition. Specifically, we studied seed fate (predation, fungi infection, emergence) and subsequent seedling performance (mortality during the first summer and overall recruitment after 2 years) of four co-occurring Mediterranean tree species (Quercus ilex, Quercus faginea, Juniperus thurifera, Pinus nigra). We related these processes to the dominant species composition, microhabitat heterogeneity, herb cover and seed mass. The identity of the dominant species in the forest canopy was more important for recruitment than the forest canopy being dominated by conspecific vs. heterospecific species. The patterns we found suggest that biotic interactions such as facilitation (lower mortality under the canopies) and herb competition (during emergence of J. thurifera) are relevant during recruitment. Moreover, our results pointed to ontogenetic conflicts regarding the seed mass of Q. faginea and to density-dependent seed mortality for Q. ilex, rarely described in Mediterranean ecosystems. We propose that our study species experience population growth in forests dominated by heterospecifics where the recruitment success depends on habitat heterogeneity and on moderated biotic and abiotic stresses created by each species. Our results reveal patterns and mechanisms involved in recruitment constraints that add complexity to the well-known drought-related processes in Mediterranean ecosystems.

  7. Modular ionizing sterilizer (MIS)

    International Nuclear Information System (INIS)

    Freijo, Jose L.

    1999-01-01

    A transportable device designed to sterilize medical material and wastes by gamma irradiation is described. The sterilizer is formed by three modules: one of the modules contains the gamma source and can be removed to transport and transfer the source, the other modules are designed to introduce and draw out the materials to be irradiated

  8. Neutrino masses and oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, A Yu

    1996-11-01

    New effects related to refraction of neutrinos in different media are reviewed and implication of the effects to neutrino mass and mixing are discussed. Patterns of neutrino masses and mixing implied by existing hints/bounds are described. Recent results on neutrino mass generation are presented. They include neutrino masses in SO(10) GUT`s and models with anomalous U(1), generation of neutrino mass via neutrino-neutralino mixing, models of sterile neutrino. (author). 95 refs, 9 figs.

  9. Analysis of L-band radiometric data over the Mediterranean Sea from the SMOS Validation Rehearsal campaign

    Science.gov (United States)

    Gabarro, C.; Talone, M.; Font, J.

    2009-04-01

    L-band radiometric data obtained with a real aperture airborne radiometer during SMOS validation Rehearsal campaign (April-May 2008) over the NW Mediterranean Sea have been analysed. EMIRAD, a fully polarimetric radiometer developed by the Technical University of Denmark operating in the 1400 - 1427 MHz band, was mounted on board a Skyvan aircraft from the Helsinki University of Technology. Two antennas were used: one facing nadir with 37.6° full aperture at half-power; and one placed towards the rear of the aircraft at 40° zenith angle with 30.6° full aperture at half-power. Two transit flights over the sea from Marseille to Valencia (19 April 2008) and from Valencia to Marseille (3 May 2008) have been studied. Two meteorological and oceanographic buoys were moored 40 Km offshore in front of Tarragona and were overflown during these transits. Additionally, information on sea surface temperature (SST) and sea surface salinity (SSS) was obtained from operational model outputs (Mediterranean Forecasting System - Mediterranean Operational Oceanography Network) and wind speed from QuikSCAT. Measured brightness temperatures (Tb) have been compared with modelled Tb, using a semi-empirical emissivity model: Klein and Swift model is used to define the dielectric constant and Hollinger model for the rough sea emissivity contribution. Comparisons show that in general measured Tb variability fits with modelled variability, although a bias is observed in the aft V channel.

  10. Strategies for rearing of rabbit does

    NARCIS (Netherlands)

    Rommers, J.M.

    2003-01-01

    This thesis describes the effects of different rearing strategies for young rabbit does on body development and reproduction performance. In current rearing, does are often fed to appetite from weaning to first insemination. First insemination is applied when 75 to 80% of mature body weight (BW) is

  11. Dynamic sterilization of titanium implants with ultraviolet light

    International Nuclear Information System (INIS)

    Singh, S.; Schaaf, N.G.

    1989-01-01

    All implantable devices must be sterile. However, autoclaves produce poor surface properties that jeopardize the integration process. The application of a modified ultraviolet light source has proven to enhance bioreactivity by controlling surface properties, but it lacks validation of its sterilization capabilities. Forty-eight titanium implants were contaminated with spores of the biological indicator Bacillus stearothermophilus and subjected to dynamic sterilization by ultraviolet light. Forty-seven of the implants were successfully sterilized, as indicated by not producing turbidity in a suitable growth medium. This sterilization technique only requires a 20-second exposure to achieve sterility

  12. Development of active rear steer actuator. Development of four wheel steer actuator for active safety; Active rear steer actuator no kaihatsu. Yobo anzen ni muketa 4WS actuator no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Yamanaka, T [Aisin Seiki Co. Ltd., Aichi (Japan)

    1997-10-01

    Recently, ecology, energy saving and safety have become important issues. And Active Safety is spotlighted in vehicle control area. Many researches and developments on four wheel steer system have been done to improve vehicle stability. We have developed the Active Rear Steer system with electromechanical Actuator, which is mass-productive, compact, and high response and durable. 10 figs., 5 tabs.

  13. Sterile neutrino dark matter with supersymmetry

    Science.gov (United States)

    Shakya, Bibhushan; Wells, James D.

    2017-08-01

    Sterile neutrino dark matter, a popular alternative to the WIMP paradigm, has generally been studied in non-supersymmetric setups. If the underlying theory is supersymmetric, we find that several interesting and novel dark matter features can arise. In particular, in scenarios of freeze-in production of sterile neutrino dark matter, its superpartner, the sterile sneutrino, can play a crucial role in early Universe cosmology as the dominant source of cold, warm, or hot dark matter, or of a subdominant relativistic population of sterile neutrinos that can contribute to the effective number of relativistic degrees of freedom Neff during big bang nucleosynthesis.

  14. Sterile neutrinos beyond LSND at the neutrino factory

    International Nuclear Information System (INIS)

    Meloni, Davide; Tang Jian; Winter, Walter

    2010-01-01

    We discuss the effects of one additional sterile neutrino at the Neutrino Factory. Compared to earlier analyses, which have been motivated by Liquid Scintillator Neutrino Detector (LSND) results, we do not impose any constraint on the additional mass squared splitting. This means that the additional mass eigenstate could, with small mixings, be located among the known ones, as it is suggested by the recent analysis of cosmological data. We use a self-consistent framework at the Neutrino Factory without any constraints on the new parameters. We demonstrate for a combined short and long baseline setup that near detectors can provide the expected sensitivity at the LSND-motivated Δm 41 2 -range, while some sensitivity can also be obtained in the region of the atmospheric mass splitting from the long baselines. We point out that limits on such very light sterile neutrinos may also be obtained from a reanalysis of atmospheric and solar neutrino oscillation data, as well as from supernova neutrino observations. In the second part of the analysis, we compare our sensitivity with the existing literature using additional assumptions, such as |Δm 41 2 |>>|Δm 31 2 |, leading to averaging of the fast oscillations in the far detectors. We demonstrate that while the Neutrino Factory has excellent sensitivity compared to existing studies using similar assumptions, one has to be very careful interpreting these results for a combined short and long baseline setup where oscillations could occur in the near detectors. We also test the impact of additional ν τ detectors at the short and long baselines, and we do not find a substantial improvement of the sensitivities.

  15. Use of gamma radiation of Cobalt-60 aiming at the quarentenary treatment and the sterilization of Stenoma catenifer Walsingham (Lepidoptera: Elachistidae)

    International Nuclear Information System (INIS)

    Silva, L.K.F.; Arthur, V.; Nava, D.E.; Parra, J.R.P.

    2007-01-01

    The objective of this work was verify the influence of gamma radiation of Cobalt-60, in the avocado moth Stenoma catenifer Walsingham (Lepidoptera: Elachistidae). For this research, insects were irradiated in all phases of their life cycle with doses varying from 0 to 600 Gy and they were maintained at the temperature of 25 +/- 2 deg C, relative humidity of 70 +/- 10% and photofase of 14 h. The species was reared on natural diet, avocado seeds, variety Breda. According to the obtained results, was verified that the lethal dose of gamma radiation to S. catenifer larvae and pupae was of 300 Gy. The sterile dose for upcoming adults from irradiated S. catenifer larvae, was of 100 Gy; for adults coming from irradiated pupas was of 150 Gy and for irradiated adults was of 200 Gy. The use the gamma radiation as treatment quarentine of S. catenifer was efficient, should be treated them with doses able to promote the sterilization of insect, without committing your qualities physical-chemistries and sensorial of fruits. Therefore, is suggested the treatment with the dose of 50 Gy for fruits infested with eggs and 150 Gy for fruits infested with larvae and pupas of S. catenifer. For use the sterile insect technique is recommended the irradiation of pupas and adults with doses of 150 Gy and 200 Gy, respectively [pt

  16. Transferability of the Mediterranean Diet to Non-Mediterranean Countries. What Is and What Is Not the Mediterranean Diet.

    Science.gov (United States)

    Martínez-González, Miguel Ángel; Hershey, Maria Soledad; Zazpe, Itziar; Trichopoulou, Antonia

    2017-11-08

    Substantial evidence has verified the Mediterranean diet's (MedDiet) nutritional adequacy, long-term sustainability, and effectiveness for preventing hard clinical events from cardiovascular disease (CVD), as well as increasing longevity. This article includes a cumulative meta-analysis of prospective studies supporting a strong inverse association between closer adherence to the MedDiet and the incidence of hard clinical events of CVD. The MedDiet has become an increasingly popular topic of interest when focusing on overall food patterns rather than single nutrient intake, not only in Mediterranean countries, but also globally. However, several myths and misconceptions associated with the traditional Mediterranean diet should be clearly addressed and dispelled, particularly those that label as "Mediterranean" an eating pattern that is not in line with the traditional Mediterranean diet. The transferability of the traditional MedDiet to the non-Mediterranean populations is possible, but it requires a multitude of changes in dietary habits. New approaches for promoting healthy dietary behavior consistent with the MedDiet will offer healthful, sustainable, and practical strategies at all levels of public health. The following article presents practical resources and knowledge necessary for accomplishing these changes.

  17. Genetic complexity underlying hybrid male sterility in Drosophila.

    Science.gov (United States)

    Sawamura, Kyoichi; Roote, John; Wu, Chung-I; Yamamoto, Masa-Toshi

    2004-02-01

    Recent genetic analyses of closely related species of Drosophila have indicated that hybrid male sterility is the consequence of highly complex synergistic effects among multiple genes, both conspecific and heterospecific. On the contrary, much evidence suggests the presence of major genes causing hybrid female sterility and inviability in the less-related species, D. melanogaster and D. simulans. Does this contrast reflect the genetic distance between species? Or, generally, is the genetic basis of hybrid male sterility more complex than that of hybrid female sterility and inviability? To clarify this point, the D. simulans introgression of the cytological region 34D-36A to the D. melanogaster genome, which causes recessive male sterility, was dissected by recombination, deficiency, and complementation mapping. The 450-kb region between two genes, Suppressor of Hairless and snail, exhibited a strong effect on the sterility. Males are (semi-)sterile if this region of the introgression is made homozygous or hemizygous. But no genes in the region singly cause the sterility; this region has at least two genes, which in combination result in male sterility. Further, the males are less fertile when heterozygous with a larger introgression, which suggests that dominant modifiers enhance the effects of recessive genes of male sterility. Such an epistatic view, even in the less-related species, suggests that the genetic complexity is special to hybrid male sterility.

  18. Inheritance of sterility in Dysdercus koenigii F. (Hemiptera: Pyrrhocoridae)

    International Nuclear Information System (INIS)

    Harwalkar, M.R.; Rahalkar, G.W.

    1979-01-01

    It has been suggested that for the control of Lepidopterous populations, release of fully competitive partially sterile males would be more advantageous than the release of completely sterile males. This suggestion is based on the fact, elucidated in many studies, that partially sterilized males mated to normal females produce totally sterile or partially sterile progeny. In Hemiptera too, F 1 progeny of partially sterile males has been shown to inherit sterility. Individual impact of sterility inherited by either sex of the F 1 progeny on population growth has been studied in an hemipteran insect Dysdercus koenigii. A dose of 7 krad induces near-complete sterility in males. When males irradiated with substerilizing doses of 1,2 and 3 krad were crossed with normal females, F 1 progeny of both sexes was partially sterile : the female being more sterile than the males. When the F 1 progeny was intercrossed, there was enhanced reduction in progeny production. (auth.)

  19. Electrolytic silver ion cell sterilizes water supply

    Science.gov (United States)

    Albright, C. F.; Gillerman, J. B.

    1968-01-01

    Electrolytic water sterilizer controls microbial contamination in manned spacecraft. Individual sterilizer cells are self-contained and require no external power or control. The sterilizer generates silver ions which do not impart an unpleasant taste to water.

  20. Studies on the infection rates and transmission characteristics of pathogenic trypanosomes in laboratory reared Glossina species as part of the SIT programme. Part of a coordinated programme on use of radiation and isotopes to develop diets for mass rearing hematophagous insects for sterile insect releases and to study disease transmission by these vectors

    International Nuclear Information System (INIS)

    Moloo, S.K.

    1985-02-01

    The releases of sterile male tsetse in tsetse control programmes will potentially increase the trypanosomiasis risk in the affected area. Hence appropriate measures should be integrated in any SIR method of tsetse control campaign in order to provide adequate protection to man and his livestock

  1. Genomic networks of hybrid sterility.

    Science.gov (United States)

    Turner, Leslie M; White, Michael A; Tautz, Diethard; Payseur, Bret A

    2014-02-01

    Hybrid dysfunction, a common feature of reproductive barriers between species, is often caused by negative epistasis between loci ("Dobzhansky-Muller incompatibilities"). The nature and complexity of hybrid incompatibilities remain poorly understood because identifying interacting loci that affect complex phenotypes is difficult. With subspecies in the early stages of speciation, an array of genetic tools, and detailed knowledge of reproductive biology, house mice (Mus musculus) provide a model system for dissecting hybrid incompatibilities. Male hybrids between M. musculus subspecies often show reduced fertility. Previous studies identified loci and several X chromosome-autosome interactions that contribute to sterility. To characterize the genetic basis of hybrid sterility in detail, we used a systems genetics approach, integrating mapping of gene expression traits with sterility phenotypes and QTL. We measured genome-wide testis expression in 305 male F2s from a cross between wild-derived inbred strains of M. musculus musculus and M. m. domesticus. We identified several thousand cis- and trans-acting QTL contributing to expression variation (eQTL). Many trans eQTL cluster into eleven 'hotspots,' seven of which co-localize with QTL for sterility phenotypes identified in the cross. The number and clustering of trans eQTL-but not cis eQTL-were substantially lower when mapping was restricted to a 'fertile' subset of mice, providing evidence that trans eQTL hotspots are related to sterility. Functional annotation of transcripts with eQTL provides insights into the biological processes disrupted by sterility loci and guides prioritization of candidate genes. Using a conditional mapping approach, we identified eQTL dependent on interactions between loci, revealing a complex system of epistasis. Our results illuminate established patterns, including the role of the X chromosome in hybrid sterility. The integrated mapping approach we employed is applicable in a broad

  2. Radiation sterilization of skin allograft

    International Nuclear Information System (INIS)

    Kairiyama, E.; Horak, C.; Spinosa, M.; Pachado, J.; Schwint, O.

    2009-01-01

    In the treatment of burns or accidental loss of skin, cadaveric skin allografts provide an alternative to temporarily cover a wounded area. The skin bank facility is indispensable for burn care. The first human skin bank was established in Argentina in 1989; later, 3 more banks were established. A careful donor selection is carried out according to the national regulation in order to prevent transmissible diseases. As cadaveric human skin is naturally highly contaminated, a final sterilization is necessary to reach a sterility assurance level (SAL) of 10 -6 . The sterilization dose for 106 batches of processed human skin was determined on the basis of the Code of Practice for the Radiation Sterilization of Tissue Allografts: Requirements for Validation and Routine Control (2004) and ISO 11137-2 (2006). They ranged from 17.6 to 33.4 kGy for bioburdens of >10-162.700 CFU/100 cm 2 . The presence of Gram negative bacteria was checked for each produced batch. From the analysis of the experimental results, it was observed that the bioburden range was very wide and consequently the estimated sterilization doses too. If this is the case, the determination of a tissue-specific dose per production batch is necessary to achieve a specified requirement of SAL. Otherwise if the dose of 25 kGy is preselected, a standardized method for substantiation of this dose should be done to confirm the radiation sterilization process.

  3. Radiation sterilization of skin allograft

    Science.gov (United States)

    Kairiyama, E.; Horak, C.; Spinosa, M.; Pachado, J.; Schwint, O.

    2009-07-01

    In the treatment of burns or accidental loss of skin, cadaveric skin allografts provide an alternative to temporarily cover a wounded area. The skin bank facility is indispensable for burn care. The first human skin bank was established in Argentina in 1989; later, 3 more banks were established. A careful donor selection is carried out according to the national regulation in order to prevent transmissible diseases. As cadaveric human skin is naturally highly contaminated, a final sterilization is necessary to reach a sterility assurance level (SAL) of 10 -6. The sterilization dose for 106 batches of processed human skin was determined on the basis of the Code of Practice for the Radiation Sterilization of Tissue Allografts: Requirements for Validation and Routine Control (2004) and ISO 11137-2 (2006). They ranged from 17.6 to 33.4 kGy for bioburdens of >10-162.700 CFU/100 cm 2. The presence of Gram negative bacteria was checked for each produced batch. From the analysis of the experimental results, it was observed that the bioburden range was very wide and consequently the estimated sterilization doses too. If this is the case, the determination of a tissue-specific dose per production batch is necessary to achieve a specified requirement of SAL. Otherwise if the dose of 25 kGy is preselected, a standardized method for substantiation of this dose should be done to confirm the radiation sterilization process.

  4. Somatic indexes, chemical-nutritive characteristics and metal content in caught and reared sharpsnout seabream (Diplodus puntazzo

    Directory of Open Access Journals (Sweden)

    Giuseppe Moniello

    2010-01-01

    Full Text Available The aim of this study was to compare some somatic indexes, chemical-nutritive characteristics and the contents of some metals (Pb, Cu, Cr and Zn in the whole body and fillet from caught and reared sharpsnout seabream (Diplodus puntazzo. The fish came from three different conditions: reared in marine cages (R, captured in a natural lagoon (L and in the Mediterranean sea (S. Thirty fish per group, divided into three weight categories (100±15.3, 200±18.7 and 300±20.4g, were used for the trial. Reared sharpsnout seabream showed higher amounts of celomatic fat (3.41%, 2.43%, 0.21%, respectively for R, L and S and total lipid (13.86%, 11.23% and 5.06% respectively for R, L and S, and lower moisture (64.14%, 65.54%, 71.53% and protein (17.73, 19.03 and 19.17% than those caught in the lagoon and sea. The whole body of reared fish contained lower amounts of lead (0.70, 0.75 and 0.97mg/kg, respectively for R, L and S, copper (0.15, 0.38, 0.25mg/kg chrome (2.19, 3.52, 3.77mg/kg and higher zinc contents (63.47, 53.42, 47.31mg/kg than caught fish. Fatty acids from sharpsnout seabream fillets showed a high lipid quality as confirmed also by low values of Thrombogenic index (0.36, 0.30 and 0.22, respectively for L, S, R and Atherogenic index (0.47, 0.42 and 0.33, respectively for L, S, R. Reared sharpsnout seabream showed lower saturated fatty acid values (26.44%, 32.21%, 34.85%, respectively for R, S, L and higher oleic acid amount (21.61%, 19.15%, 11.99%, respectively for R, L and S. The subjects captured in the sea had a higher arachidonic acid content (5.44%, 1.76%, 0.59%, respectively for S, L, R. In the weight categories, the 100g subjects, showed higher incidence of viscera (VSI: 4.32%, 3.12% and 2.92%, respectively for 100, 200 and 300g and liver (HIS: 2.20%, 1.97%, and 1.77%, respectively for 100, 200 and 300g, higher moisture (69.49%, 67.03%, 64.69% and lower lipid rate (7.64%, 10.18%, 12.32%.

  5. Selection of male-sterile and dwarfism genetically modified zoysia japonica through gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Tae Woong; Song, In Ja; Kang, Hong Gyu; Jeong, Ok Cheol; Sun, Hyeon Jin; Ko, Suk Min; Lim, Pyung Ok; Song, Pill Soon; Song, Sung Jun; Lee, Hyo Yeon [Jeju National University, Jeju (Korea, Republic of)

    2010-09-15

    The aim of this study is selection of the male-sterile plant for inhibiting transgene flow through gamma-irradiation ({sup 60}Co) at the pollination and fertilization cycle of herbicide-tolerant genetically modified (GM) zoysiagrass (Zoysia japonica Steud.). High frequencies of plant mutations were obtained about 18% from M{sub 1} generation at the doses (10 to 50 Gy). We also found that some M{sub 1} plants showed male-sterile plants using de-husked seeds and comparison of stainable pollen using KI-I{sub 2} solution. Besides the effects of irradiation on pollination and fertilization cycle, various other mutation like dwarf, cold tolerance, increasing grains and mass were observed. Four of dwarfism plants were selected through comparison of morphological characteristic between control and mutants during 4 years. These results demonstrated that the gamma-irradiation on pollination and fertilization cycle is very effective to induce the various mutations, and the male-sterile mutants are useful for controlling transgene flow and developing of high quality turfgasses.

  6. Selection of male-sterile and dwarfism genetically modified zoysia japonica through gamma irradiation

    International Nuclear Information System (INIS)

    Bae, Tae Woong; Song, In Ja; Kang, Hong Gyu; Jeong, Ok Cheol; Sun, Hyeon Jin; Ko, Suk Min; Lim, Pyung Ok; Song, Pill Soon; Song, Sung Jun; Lee, Hyo Yeon

    2010-01-01

    The aim of this study is selection of the male-sterile plant for inhibiting transgene flow through gamma-irradiation ( 60 Co) at the pollination and fertilization cycle of herbicide-tolerant genetically modified (GM) zoysiagrass (Zoysia japonica Steud.). High frequencies of plant mutations were obtained about 18% from M 1 generation at the doses (10 to 50 Gy). We also found that some M 1 plants showed male-sterile plants using de-husked seeds and comparison of stainable pollen using KI-I 2 solution. Besides the effects of irradiation on pollination and fertilization cycle, various other mutation like dwarf, cold tolerance, increasing grains and mass were observed. Four of dwarfism plants were selected through comparison of morphological characteristic between control and mutants during 4 years. These results demonstrated that the gamma-irradiation on pollination and fertilization cycle is very effective to induce the various mutations, and the male-sterile mutants are useful for controlling transgene flow and developing of high quality turfgasses

  7. Is socioeconomic status of the rearing environment causally related to obesity in the offspring?

    Directory of Open Access Journals (Sweden)

    Kevin R Fontaine

    Full Text Available We attempt to elucidate whether there might be a causal connection between the socioeconomic status (SES of the rearing environment and obesity in the offspring using data from two large-scale adoption studies: (1 The Copenhagen Adoption Study of Obesity (CASO, and (2 The Survey of Holt Adoptees and Their Families (HOLT. In CASO, the SES of both biological and adoptive parents was known, but all children were adopted. In HOLT, only the SES of the rearing parents was known, but the children could be either biological or adopted. After controlling for relevant covariates (e.g., adoptee age at measurement, adoptee age at transfer, adoptee sex the raw (unstandardized regression coefficients for adoptive and biological paternal SES on adoptee body mass index (BMI: kg/m(2 in CASO were -.22 and -.23, respectively, both statistically significant (p = 0.01. Controlling for parental BMI (both adoptive and biological reduced the coefficient for biological paternal SES by 44% (p = .034 and the coefficient for adoptive paternal SES by 1%. For HOLT, the regression coefficients for rearing parent SES were -.42 and -.25 for biological and adoptive children, respectively. Controlling for the average BMI of the rearing father and mother (i.e., mid-parental BMI reduced the SES coefficient by 47% in their biological offspring (p≤.0001, and by 12% in their adoptive offspring (p = .09. Thus, despite the differing structures of the two adoption studies, both suggest that shared genetic diathesis and direct environmental transmission contribute about equally to the association between rearing SES and offspring BMI.

  8. Why are rates of sterilization in decline? A pilot study designed to explore reasons for declining female sterilization in Scotland.

    Science.gov (United States)

    Chen, Zhong E; Glasier, Anna; Warner, Pamela

    2008-10-01

    In the last decade, female sterilization had been in decline throughout the UK. It is not clear whether fewer women are requesting sterilization or whether the universal enthusiasm for long-acting reversible methods is leading health professionals to discourage women from being sterilized. Since correct and consistent use of alternative, reversible contraceptive methods depends somewhat on their acceptability, it is important to determine whether women are being refused sterilization or whether they are freely choosing other methods. This study aims to explore whether female sterilization is being widely considered as a contraceptive method, the reasons for choosing or rejecting it, and whether women are being discouraged by health professionals from being sterilized. A self-completed questionnaire survey among 205 women aged 30 to 50 years who felt that their family was complete attending a family planning clinic in Scotland. Of the 203 women included in the study, 151 (74.4%) had heard of female sterilization, 90 had discussed it with someone (60%) and 87 (58%) had considered it as a contraceptive option. Of the 56 women who consulted their family doctor about sterilization, almost half (27; 48%) were not referred to a hospital and fewer than one (17, 30.4%) in three of them was eventually sterilized or had arrangements in place to get it done. Free-text comments from the women revealed a variety of reasons for not choosing female sterilization and suggested that some women are being deterred from sterilization. The study suggests that some women are being actively encouraged by health professionals to use long-acting reversible contraceptive methods and discouraged from choosing sterilization. However, other women recognize for themselves the wisdom of keeping their fertility options open.

  9. Sterilization of instruments in solar ovens

    Energy Technology Data Exchange (ETDEWEB)

    Fjendbo Joergensen, A. [Odense Univ. Hospital, Dept. of Infectious Diseases, Odense (Denmark); Noehr, K. [Odense Technical College, Dept. of Metal, Odense (Denmark); Boisen, F. [The Danish Veterinary and Food Administration Funen, Dept. of Microbiology, Odense (Denmark)

    2000-07-01

    The sterilization of instruments in rural health clinics in less developed countries is an increasing problem because chemical methods can no longer be recommended and wood fuel is becoming more and more scarce. Thus, it seemed obvious to try to utilize solar energy for sterilization purposes. A solar oven was designed and manufactured using local materials and simple tools. The solar oven was tested by physical, chemical, and microbiological methods. A mathematical model for the sterilization effect was developed and programmed into a microprocessor that was connected to a thermocouple. The microprocessor switches on a green light when the sterilization is completed. After successful testing, the oven was built into the west-facing wall of a rural health clinic and used daily for sterilization. The oven was able to generate temperatures above 180 deg. C. On all days with direct sunlight the oven fulfilled the international recommendations for hot air sterilization because no growth could be detected from any of the test bacteria spores. The chemical indicators Brownes tubes types 3 and 5 also changed colours. The solar oven was easy to use for the clinic staff, but during the seasons with low sun position (in Tanzania, December and June) it was difficult to achieve a high enough temperature for sterilization. Therefore, if the method is to be used throughout the year the oven must be moved to collect the sun's rays from several directions, or the clinic must have more than one solar oven facing in different directions. We conclude that the solar oven is a realistic method for sterilization of instruments. (au)

  10. Cryoradiation sterilization - contemporary state and outlook

    International Nuclear Information System (INIS)

    Talrose, V.L.

    1995-01-01

    The new approach of radiation sterilization -cryoradiosterilization with programmed freezing - was developed for pharmaceutical solutions. Both scientific and technical problems are solved, the results are discussed. Programmed freezing of vials with the drug's solutions provides the high stability of soluted components with biological activity at sterilizing irradiation without significant change of sterilization doses. Physical, chemical, biological and pharmacological properties of a lot of drug solutions for injection satisfy official requirements after cryoradiation sterilization treatment. This method seems to be especially important for the protein systems which could be infected by dangerous viruses (VIH, hepatitis B): blood plasma, diagnostic sera, protein preparations manufactured from donor's blood, etc. (Author)

  11. Currently available devices for female sterilization.

    Science.gov (United States)

    Chapman, Lynne; Magos, Adam

    2005-09-01

    Sterilization is now the method of family planning most commonly used in the world. Over the last 150 years, research has evolved in the search for the ideal method of female sterilization. The procedure should ideally have high efficacy, be readily accessible and be personally and culturally acceptable. The method should be simple, quick, easily learned and be able to be performed in an outpatient setting without general anesthesia. The most common and effective method for sterilization has, thus far, been via the laparoscopic route. Hysteroscopic sterilization, however, potentially fulfills many of these ideal criteria, but until recently has remained more of a concept than a reality.

  12. Design Report for ACP Hot Cell Rear Door

    Energy Technology Data Exchange (ETDEWEB)

    Ku, J. H.; Kwon, K. C.; Choung, W. M.; Cho, I. J.; Kook, D. H.; Lee, W. K.; You, G. S.; Lee, E. P.; Park, S. W

    2005-12-15

    A hot-cell facility was constructed at the IMEF building for the demonstrate ACP process. ACP hot-cell consists of process cell and maintenance cell, and each cell has rear door. Since this facility was constructed at basement floor, all process materials, equipment and radioactive materials are take in and out through the rear door. Also, this door can be an access route of workers for the maintenance works. Therefore ACP hot-cell rear doors must maintain the radiation shielding, sealing, mechanical and structural safety. This report presents design criteria, design contents of each part and driving part. It was confirmed that the rear doors sufficiently maintain the safety through the structural analysis and shielding analysis. Also, it was confirmed that the rear doors were constructed as designed by the gamma scanning test after the installation.

  13. Design Report for ACP Hot Cell Rear Door

    International Nuclear Information System (INIS)

    Ku, J. H.; Kwon, K. C.; Choung, W. M.; Cho, I. J.; Kook, D. H.; Lee, W. K.; You, G. S.; Lee, E. P.; Park, S. W.

    2005-12-01

    A hot-cell facility was constructed at the IMEF building for the demonstrate ACP process. ACP hot-cell consists of process cell and maintenance cell, and each cell has rear door. Since this facility was constructed at basement floor, all process materials, equipment and radioactive materials are take in and out through the rear door. Also, this door can be an access route of workers for the maintenance works. Therefore ACP hot-cell rear doors must maintain the radiation shielding, sealing, mechanical and structural safety. This report presents design criteria, design contents of each part and driving part. It was confirmed that the rear doors sufficiently maintain the safety through the structural analysis and shielding analysis. Also, it was confirmed that the rear doors were constructed as designed by the gamma scanning test after the installation

  14. Non-Unitarity, sterile neutrinos, and Non-Standard neutrino Interactions

    CERN Document Server

    Blennow, Mattias; Fernandez-Martinez, Enrique; Hernandez-Garcia, Josu; Lopez-Pavon, Jacobo

    2017-04-27

    The simplest Standard Model extension to explain neutrino masses involves the addition of right-handed neutrinos. At some level, this extension will impact neutrino oscillation searches. In this work we explore the differences and similarities between the case in which these neutrinos are kinematically accessible (sterile neutrinos) or not (mixing matrix non-unitarity). We clarify apparent inconsistencies in the present literature when using different parametrizations to describe these effects and recast both limits in the popular neutrino non-standard interaction (NSI) formal- ism. We find that, in the limit in which sterile oscillations are averaged out at the near detector, their effects at the far detector coincide with non-unitarity at leading order, even in presence of a matter potential. We also summarize the present bounds existing in both limits and compare them with the expected sensitivities of near-future facilities taking the DUNE proposal as a bench- mark. We conclude that non-unitarity effects ...

  15. Warm Dark Matter Sterile Neutrinos in Electron Capture and Beta Decay Spectra

    Directory of Open Access Journals (Sweden)

    O. Moreno

    2016-01-01

    Full Text Available We briefly review the motivation to search for sterile neutrinos in the keV mass scale, as dark matter candidates, and the prospects to find them in beta decay or electron capture spectra, with a global perspective. We describe the fundamentals of the neutrino flavor-mass eigenstate mismatch that opens the possibility of detecting sterile neutrinos in such ordinary nuclear processes. Results are shown and discussed for the effect of heavy neutrino emission in electron capture in Holmium 163 and in two isotopes of Lead, 202 and 205, as well as in the beta decay of Tritium. We study the deexcitation spectrum in the considered cases of electron capture and the charged lepton spectrum in the case of Tritium beta decay. For each of these cases, we define ratios of integrated transition rates over different regions of the spectrum under study and give new results that may guide and facilitate the analysis of possible future measurements, paying particular attention to forbidden transitions in Lead isotopes.

  16. Compodock, a new device for sterile docking

    NARCIS (Netherlands)

    van der Meer, P. F.; Biekart, F. T.; Pietersz, R. N.; Rebers, S. P.; Reesink, H. W.

    2000-01-01

    BACKGROUND: A new device for sterile docking, the Compodock (Fresenius NPBI Transfusion Technology), was developed for connecting PVC tubing for medical use while maintaining sterility. STUDY DESIGN AND METHODS: Sterility of the connections was assessed by welding tubing with a heavy exterior

  17. MINOS Sterile Neutrino Search

    Energy Technology Data Exchange (ETDEWEB)

    Koskinen, David Jason [Univ. College London, Bloomsbury (United Kingdom)

    2009-02-01

    The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline accelerator neutrino experiment designed to measure properties of neutrino oscillation. Using a high intensity muon neutrino beam, produced by the Neutrinos at Main Injector (NuMI) complex at Fermilab, MINOS makes two measurements of neutrino interactions. The first measurement is made using the Near Detector situated at Fermilab and the second is made using the Far Detector located in the Soudan Underground laboratory in northern Minnesota. The primary goal of MINOS is to verify, and measure the properties of, neutrino oscillatio