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Sample records for engineered male sterility

  1. Towards male sterility in Pinus radiata--a stilbene synthase approach to genetically engineer nuclear male sterility.

    Science.gov (United States)

    Höfig, Kai P; Möller, Ralf; Donaldson, Lloyd; Putterill, Joanna; Walter, Christian

    2006-05-01

    A male cone-specific promoter from Pinus radiata D. Don (radiata pine) was used to express a stilbene synthase gene (STS) in anthers of transgenic Nicotiana tabacum plants, resulting in complete male sterility in 70% of transformed plants. Three plants were 98%-99.9% male sterile, as evidenced by pollen germination. To identify the stage at which transgenic pollen first developed abnormally, tobacco anthers from six different developmental stages were assayed microscopically. Following the release of pollen grains from tetrads, transgenic pollen displayed an increasingly flake-like structure, which gradually rounded up during the maturation process. We further investigated whether STS expression may have resulted in an impaired flavonol or sporopollenin formation. A specific flavonol aglycone stain was used to demonstrate that significant amounts of these substances were produced only in late stages of normal pollen development, therefore excluding a diminished flavonol aglycone production as a reason for pollen ablation. A detailed analysis of the exine layer by transmission electron microscopy revealed minor structural changes in the exine layer of ablated pollen, and pyrolysis-gas chromatography-mass spectroscopy indicated that the biochemistry of sporopollenin production was unaffected. The promoter-STS construct may be useful for the ablation of pollen formation in coniferous gymnosperms and male sterility may potentially be viewed as a prerequisite for the commercial use of transgenic conifers.

  2. Efficient transformation of Kalanchoe blossfeldiana and production of male-sterile plants by engineered anther ablation.

    Science.gov (United States)

    García-Sogo, Begoña; Pineda, Benito; Castelblanque, Lourdes; Antón, Teresa; Medina, Mónica; Roque, Edelín; Torresi, Claudia; Beltrán, José Pío; Moreno, Vicente; Cañas, Luis Antonio

    2010-01-01

    Engineered male sterility in ornamental plants has many applications such as facilitate hybrid seed production, eliminate pollen allergens, reduce the need for deadheading to extend the flowering period, redirect resources from seeds to vegetative growth, increase flower longevity and prevent gene flow between genetically modified and related native plants. We have developed a reliable and efficient Agrobacterium-mediated protocol for the genetic transformation of different Kalanchoe blossfeldiana commercial cultivars. Transformation efficiency for cv. 'Hillary' was 55.3% whereas that of cv. 'Tenorio' reached 75.8%. Selection was carried out with the nptII gene and increasing the kanamycin concentration from 25 to 100 mg l(-1) allowed to reduced escapes from 50 to 60% to virtually 0%. This method was used to produce male-sterile plants through engineered anther ablation. In our approach, we tested a male sterility chimaeric gene construct (PsEND1::barnase) to evaluate its effectiveness and effect on phenotype. No significant differences were found in the growth patterns between the transgenic lines and the wild-type plants. No viable pollen grains were observed in the ablated anthers of any of the lines carrying the PsEND1::barnase construct, indicating that the male sterility was complete. In addition, seed set was completely abolished in all the transgenic plants obtained. Our engineered male-sterile approach could be used, alone or in combination with a female-sterility system, to reduce the invasive potential of new ornamentals, which has become an important environmental problem in many countries.

  3. Engineered Dwarf Male-Sterile Rice: A Promising Genetic Tool for Facilitating Recurrent Selection in Rice.

    Science.gov (United States)

    Ansari, Afsana; Wang, Chunlian; Wang, Jian; Wang, Fujun; Liu, Piqing; Gao, Ying; Tang, Yongchao; Zhao, Kaijun

    2017-01-01

    Rice is a crop feeding half of the world's population. With the continuous raise of yield potential via genetic improvement, rice breeding has entered an era where multiple genes conferring complex traits must be efficiently manipulated to increase rice yield further. Recurrent selection is a sound strategy for manipulating multiple genes and it has been successfully performed in allogamous crops. However, the difficulties in emasculation and hand pollination had obstructed efficient use of recurrent selection in autogamous rice. Here, we report development of the dwarf male-sterile rice that can facilitate recurrent selection in rice breeding. We adopted RNAi technology to synergistically regulate rice plant height and male fertility to create the dwarf male-sterile rice. The RNAi construct pTCK-EGGE, targeting the OsGA20ox2 and OsEAT1 genes, was constructed and used to transform rice via Agrobacterium -mediated transformation. The transgenic T0 plants showing largely reduced plant height and complete male-sterile phenotypes were designated as the dwarf male-sterile plants. Progenies of the dwarf male-sterile plants were obtained by pollinating them with pollens from the wild-type. In the T1 and T2 populations, half of the plants were still dwarf male-sterile; the other half displayed normal plant height and male fertility which were designated as tall and male-fertile plants. The tall and male-fertile plants are transgene-free and can be self-pollinated to generate new varieties. Since emasculation and hand pollination for dwarf male-sterile rice plants is no longer needed, the dwarf male-sterile rice can be used to perform recurrent selection in rice. A dwarf male-sterile rice-based recurrent selection model has been proposed.

  4. Production of engineered long-life and male sterile Pelargonium plants

    Directory of Open Access Journals (Sweden)

    García-Sogo Begoña

    2012-08-01

    Full Text Available Abstract Background Pelargonium is one of the most popular garden plants in the world. Moreover, it has a considerable economic importance in the ornamental plant market. Conventional cross-breeding strategies have generated a range of cultivars with excellent traits. However, gene transfer via Agrobacterium tumefaciens could be a helpful tool to further improve Pelargonium by enabling the introduction of new genes/traits. We report a simple and reliable protocol for the genetic transformation of Pelargonium spp. and the production of engineered long-life and male sterile Pelargonium zonale plants, using the pSAG12::ipt and PsEND1::barnase chimaeric genes respectively. Results The pSAG12::ipt transgenic plants showed delayed leaf senescence, increased branching and reduced internodal length, as compared to control plants. Leaves and flowers of the pSAG12::ipt plants were reduced in size and displayed a more intense coloration. In the transgenic lines carrying the PsEND1::barnase construct no pollen grains were observed in the modified anther structures, which developed instead of normal anthers. The locules of sterile anthers collapsed 3–4 days prior to floral anthesis and, in most cases, the undeveloped anther tissues underwent necrosis. Conclusion The chimaeric construct pSAG12::ipt can be useful in Pelargonium spp. to delay the senescence process and to modify plant architecture. In addition, the use of engineered male sterile plants would be especially useful to produce environmentally friendly transgenic plants carrying new traits by preventing gene flow between the genetically modified ornamentals and related plant species. These characteristics could be of interest, from a commercial point of view, both for pelargonium producers and consumers.

  5. Open field release of genetically engineered sterile male Aedes aegypti in Malaysia.

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    Renaud Lacroix

    Full Text Available BACKGROUND: Dengue is the most important mosquito-borne viral disease. In the absence of specific drugs or vaccines, control focuses on suppressing the principal mosquito vector, Aedes aegypti, yet current methods have not proven adequate to control the disease. New methods are therefore urgently needed, for example genetics-based sterile-male-release methods. However, this requires that lab-reared, modified mosquitoes be able to survive and disperse adequately in the field. METHODOLOGY/PRINCIPAL FINDINGS: Adult male mosquitoes were released into an uninhabited forested area of Pahang, Malaysia. Their survival and dispersal was assessed by use of a network of traps. Two strains were used, an engineered 'genetically sterile' (OX513A and a wild-type laboratory strain, to give both absolute and relative data about the performance of the modified mosquitoes. The two strains had similar maximum dispersal distances (220 m, but mean distance travelled of the OX513A strain was lower (52 vs. 100 m. Life expectancy was similar (2.0 vs. 2.2 days. Recapture rates were high for both strains, possibly because of the uninhabited nature of the site. CONCLUSIONS/SIGNIFICANCE: After extensive contained studies and regulatory scrutiny, a field release of engineered mosquitoes was safely and successfully conducted in Malaysia. The engineered strain showed similar field longevity to an unmodified counterpart, though in this setting dispersal was reduced relative to the unmodified strain. These data are encouraging for the future testing and implementation of genetic control strategies and will help guide future field use of this and other engineered strains.

  6. Genetically conditioned male sterility

    International Nuclear Information System (INIS)

    Gottschalk, W.

    1976-01-01

    A survey is given of two different types of genetically controlled male sterility in higher plants. 'Functional' male sterility is due to the action of mutated genes causing a misdifferentiation of the growing points in different specific ways. Under the influence of the genes of this group either the stamens or the archespore tissues are not differentiated. In other mutants functionable male germ cells are produced but cannot be used for fertilizing the egg cells because the anthers remain closed or anthers and stigma become spatially separated from each other. Other genes of the group are responsible for the transformation of stamens into carpels, i.e. for a change of the hermaphrodite flower into a unisexually female one. A second type of male sterility is due to the action of ms genes influencing the course of micro-sporogenesis directly. They cause the breakdown of this process in a specific meiotic stage characteristic for each gene of the group. This breakdown is introduced by the degeneration of PMCs, microspores, or pollen grains preventing the production of male germ cells. The female sex organs remain uninfluenced. (author)

  7. Gene, protein and network of male sterility in rice

    Directory of Open Access Journals (Sweden)

    Wang eKun

    2013-04-01

    Full Text Available Rice is one of the most important model crop plants whose heterosis has been well exploited in commercial hybrid seed production via a variety of types of male sterile lines. Hybrid rice cultivation area is steadily expanding around the world, especially in Southern Asia. Characterization of genes and proteins related to male sterility aims to understand how and why the male sterility occurs, and which proteins are the key players for microspores abortion. Recently, a series of genes and proteins related to cytoplasmic male sterility, photoperiod sensitive male sterility, self-incompatibility and other types of microspores deterioration have been characterized through genetics or proteomics. Especially the latter, offers us a powerful and high throughput approach to discern the novel proteins involving in male-sterile pathways which may help us to breed artificial male-sterile system. This represents an alternative tool to meet the critical challenge of further development of hybrid rice. In this paper, we reviewed the recent developments in our understanding of male sterility in rice hybrid production across gene, protein and integrated network levels, and also, present a perspective on the engineering of male sterile lines for hybrid rice production.

  8. Induced mutant for male sterility in niger

    International Nuclear Information System (INIS)

    Sujatha, M.

    2001-01-01

    Full text: Niger (Guizotia abyssinica Cass.), an important oilseed crop of the family Compositae is highly cross-pollinated due to the twin mechanisms of protandry and incompatibility. Studies revealed the functional nature of protandry and the breakdown of incompatibility with alteration in temperature. It has very small flowers (disc florets) arranged in a capitulum that open on 3-4 consecutive days which pose problems in emasculation for cross-breeding. To induce mutations, seeds of variety 'IGP-76' were irradiated with γ-rays 200 to 1000 Gy. All seeds of M 1 plants were sown separately in individual plant-to progeny rows. The results of screening of M 2 segregating material indicated that γ-ray treatment was effective in induction of male sterility. Frequency of visible mutations were higher in sibbed progeny as compared to open pollinated population and male sterile plants were observed only in sibbed population (1000 Gy). Male sterile plants could easily be identified at the flowering stage by their altered floral morphology (disc florets transformed into ligulate ray florets) and complete absence or presence of a rudimentary anther column. Seeds were collected following sib-mating with the fertile counterparts. Progeny segregated in a ration of 3 normal : 1 male sterile. Further work on the mechanism of sterility, maintenance and linkage relationships with associated characters is under progress. This is the first report of induction of male sterility in niger through the use of physical mutagens. The availability of this mutant will be of great value for exploitation of heterosis on commercial basis. (author)

  9. Transcriptional regulation of male-sterility in 7B-1 male-sterile tomato mutant.

    Directory of Open Access Journals (Sweden)

    Vahid Omidvar

    Full Text Available The 7B-1 tomato (Solanum lycopersicum L. cv Rutgers is a male-sterile mutant with enhanced tolerance to abiotic stress, which makes it a potential candidate for hybrid seed breeding and stress engineering. To underline the molecular mechanism regulating the male-sterility in 7B-1, transcriptomic profiles of the 7B-1 male-sterile and wild type (WT anthers were studied using mRNA sequencing (RNA-Seq. In total, 768 differentially expressed genes (DEGs were identified, including 132 up-regulated and 636 down-regulated transcripts. Gene ontology (GO enrichment analysis of DEGs suggested a general impact of the 7B-1 mutation on metabolic processes, such as proteolysis and carbohydrate catabolic process. Sixteen candidates with key roles in regulation of anther development were subjected to further analysis using qRT-PCR and in situ hybridization. Cytological studies showed several defects associated with anther development in the 7B-1 mutant, including unsynchronized anther maturation, dysfunctional meiosis, arrested microspores, defect in callose degradation and abnormal tapetum development. TUNEL assay showed a defect in programmed cell death (PCD of tapetal cells in 7B-1 anthers. The present study provides insights into the transcriptome of the 7B-1 mutant. We identified several genes with altered expression level in 7B-1 (including beta-1,3 glucanase, GA2oxs, cystatin, cysteine protease, pectinesterase, TA29, and actin that could potentially regulate anther developmental processes, such as meiosis, tapetum development, and cell-wall formation/degradation.

  10. sensitive genic male sterile (PGMS) rice

    African Journals Online (AJOL)

    user

    2011-04-18

    Apr 18, 2011 ... phosphate buffered solution; TEM, transmission electron microscope; CMS, cytoplasmic male sterile; FPR, first photo reaction; SPR, second photo reaction. production of cytotoxins which instigate apoptosis. For example in Caenorhabditis elegans, the ced genes code for cystein proteases Ced-3 and Ced-4 ...

  11. Utilization of male sterility in forage crops

    International Nuclear Information System (INIS)

    Suginobu, Ken-ichi

    1982-01-01

    The genetic nature of male sterility in forage crops was reviewed. Many workers have suggested that hybrids in forage crops are quite promising. First, the selection of the most desirable parental genotype from a large original population is improtant in heterosis breeding programs. After the more promising inbreds or clones have been selected on the basis of good general combining ability, it is necessary to identify the particular single, three-way or double cross that will produce the highest yields. A high seed yield potential is also important in a new variety so that the seeds can be sold at lower prices than other varieties. A tentative scheme for hybrid seed production by using inbred lines of male sterile or normal parents is proposed. At a breeding station, the seeds for male sterile F 1 (AB), maintainer S 1 (C-S 1 ) and either maintainer or restorer S 1 s(D-S 1 , E-S 1 ) are produced from the parental clones. At a seed increase agency, the seeds for male sterile F 1 (ABC) and either maintainer or restorer S 2 (D-S 2 ) are produced. In the case that D-S 2 seed production is difficult, maintainer or restorer F 1 (DE) should be produced from D-S 1 x E-S 1 . These seeds are used for commercial seed production. Seeds of hybrid F 1 (ABCD) or hybrid F 1 (ABCDE) are for practical use. (Kaihara, S.)

  12. The dynamics of gynodioecy in Plantago lanceolata L. .1. Frequencies of male-steriles and their cytoplasmic male sterility types

    NARCIS (Netherlands)

    De Haan, A.A.; Luyten, R.M.J.M.; Bakx-Schotman, Tanja; Van Damme, J.M.M.

    1997-01-01

    The maintenance of a gynodioecious breeding system (hermaphrodites and male-steriles) was studied in Plantago lanceolata. Cytoplasmic-nuclear inheritance is important in the maintenance of male-steriles. The male-sterile trait is cytoplasmically based (CMS), and male fertility can be restored by

  13. Puzzles in modern biology. I. Male sterility, failure reveals design.

    Science.gov (United States)

    Frank, Steven A

    2016-01-01

    Many human males produce dysfunctional sperm. Various plants frequently abort pollen. Hybrid matings often produce sterile males. Widespread male sterility is puzzling. Natural selection prunes reproductive failure. Puzzling failure implies something that we do not understand about how organisms are designed. Solving the puzzle reveals the hidden processes of design.

  14. Mating competitiveness of sterile male Anopheles coluzzii in large cages.

    Science.gov (United States)

    Maïga, Hamidou; Damiens, David; Niang, Abdoulaye; Sawadogo, Simon P; Fatherhaman, Omnia; Lees, Rosemary S; Roux, Olivier; Dabiré, Roch K; Ouédraogo, Georges A; Tripet, Fréderic; Diabaté, Abdoulaye; Gilles, Jeremie R L

    2014-11-26

    Understanding the factors that account for male mating competitiveness is critical to the development of the sterile insect technique (SIT). Here, the effects of partial sterilization with 90 Gy of radiation on sexual competitiveness of Anopheles coluzzii allowed to mate in different ratios of sterile to untreated males have been assessed. Moreover, competitiveness was compared between males allowed one versus two days of contact with females. Sterile and untreated males four to six days of age were released in large cages (~1.75 sq m) with females of similar age at the following ratios of sterile males: untreated males: untreated virgin females: 100:100:100, 300:100:100, 500:100:100 (three replicates of each) and left for two days. Competitiveness was determined by assessing the egg hatch rate and the insemination rate, determined by dissecting recaptured females. An additional experiment was conducted with a ratio of 500:100:100 and a mating period of either one or two days. Two controls of 0:100:100 (untreated control) and 100:0:100 (sterile control) were used in each experiment. When males and females consort for two days with different ratios, a significant difference in insemination rate was observed between ratio treatments. The competitiveness index (C) of sterile males compared to controls was 0.53. The number of days of exposure to mates significantly increased the insemination rate, as did the increased number of males present in the untreated: sterile male ratio treatments, but the number of days of exposure did not have any effect on the hatch rate. The comparability of the hatch rates between experiments suggest that An. coluzzii mating competitiveness experiments in large cages could be run for one instead of two days, shortening the required length of the experiment. Sterilized males were half as competitive as untreated males, but an effective release ratio of at least five sterile for one untreated male has the potential to impact the fertility of

  15. Phenology, sterility and inheritance of two environment genic male sterile (EGMS) lines for hybrid rice

    NARCIS (Netherlands)

    El-Namaky, R.; Oort, van P.A.J.

    2017-01-01

    Background: 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

  16. Study of male sterility in Taiwania cryptomerioides Hayata (Taxodiaceae).

    Science.gov (United States)

    Chen, S-H; Chung, N-J; Wang, Y-N; Lee, C-L; Lee, Y-L; Tsai, P-F

    2006-08-01

    A study of male sterility over a period of three consecutive years on a conifer species endemic to Taiwan, Taiwania cryptomerioides Hayata (Taxodiaceae), was done for this article. With the aids of fluorescence and electron microscopic observations, the ontogenic processes in the fertile and sterile microsporangia are compared, using samples collected from Chitou Experimental Forest and Yeou-Shoei-Keng Clonal Orchard of the National Taiwan University, Nantou, Taiwan. The development of male strobili occurred from August to the end of March. Microsporogenesis starts with the formation of the archesporium and ends with the maturation of 2-celled pollen grains within the dehiscing microsporangium. Before meiosis, there was no significant difference in ultrastructure between the fertile and sterile microsporangia. Asynchronous pollen development with various tetrad forms may occur in the same microsporangium of either fertile or sterile strobili. However, a callose wall was observable in the fertile dyad and tetrad, but not in the sterile one. After dissolution of the callose wall, the fertile microspores were released into the locule, while some sterile microspores still retained as tetrads or dyads with intertwining of exine walls in the proximal faces. As a result, there was no well developed lamellated endexine and no granulate ectexine or intine in the sterile microspores. Eventually, the intracellular structures in sterile microspores were dramatically collapsed before anthesis. The present study shows that the abortion in pollen development is possibly attributed to the absence of the callose wall. The importance of this structure to the male sterility of T. cryptomerioides is discussed.

  17. Gamma ray induced male sterility mutant in lentil

    International Nuclear Information System (INIS)

    Srivastava, A.; Yadav, A.K.

    2001-01-01

    Full text: Male sterility refers to the failure of pollen grains to bring about effective fertilization, either due to structural default or physiological disfunctioning and has special significance in hybridization programmes. Male steriles have been produced in a number of crop plants like red gram, pigeon pea, mung bean, khesari and lentil. A completely male sterile mutant was isolated in Lens culinaris Medik, after seed treatment with 100 Gy dose of gamma rays. The male sterile mutant showed 100% pollen sterility but was morphologically more vigorous than the parent plants. It showed more branches and its leaves were bigger, more oblong and dark green. The number of flowers borne by the mutant was significantly higher than any other plant of the treatment. The size of the flowers was also increased but the anthers were smaller in size. Pollen grains were few in number, round in shape but empty and did not take up any stain, indicating that normal microsporogenesis had not taken place. This male sterile mutant was used as the female parent and pollinated with pollen of a parent. Four pods with one seed in each were formed indicating that the mutant was female fertile. The seeds were smaller than those of the parent variety and also dark coloured. The mutant showed increased vigour and flower number as compared to parental plants. Lentil is an important pulse crop and induction of variability in its germplasm is necessary for its improvement. Male steriles can be used conveniently in lentil hybridization programmes. (author)

  18. Assessing genetic variability in male sterile and low fertile citrus ...

    African Journals Online (AJOL)

    Understanding phylogenetic relationships and genetic diversity in citrus are important in clarifying genetic relationships, characterizing germplasm and the registration of new cultivars. In this study, the genetic diversity of 28 accessions of citrus including male sterile, sterile, low fertile and fertile cultivars were investigated ...

  19. Tracking the expression of photosensitive genic male sterility genes ...

    African Journals Online (AJOL)

    Photoperiod sensitive genic male sterile rice lines contain genes that induce complete sterility in high temperature and long day light length period, and revert to fertility in optimum low temperature and short day light length period. These lines are good candidates for hybrid rice seed production. The main challenge limiting ...

  20. Vasectomy occlusion techniques for male sterilization.

    Science.gov (United States)

    Cook, L A; Vliet, H; Pun, A; Gallo, M F

    2004-01-01

    Vasectomy is an increasingly popular and effective family planning method. A variety of vasectomy techniques are used worldwide including various vas occlusion techniques (excision and ligation, thermal or electrocautery, and mechanical and chemical occlusion methods), vas irrigation and fascial interposition. Vasectomy guidelines largely rely on information from observational studies. Ideally, the choice of vasectomy techniques should be based on the best available evidence from randomized controlled trials. The objective of this review was to compare the effectiveness, safety, acceptability and costs of vasectomy techniques for male sterilization. We searched the computerized databases the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Popline and LILACS. In addition, we searched the reference lists of relevant articles and book chapters. We included randomized controlled trials and controlled clinical trials comparing vasectomy techniques. We assessed all titles and abstracts located in the literature searches and two reviewers independently extracted articles identified for inclusion. Data were presented in the text of the review. Outcome measures include contraceptive efficacy, safety, discontinuation, and acceptability. Two trials compared vas occlusion with clips versus a conventional vasectomy technique; both were of poor quality. Neither trial found a difference between the two groups with regard to the primary outcome of failure to reach azoospermia. Four trials examined vas irrigation: three compared water irrigation with no irrigation and one compared water irrigation with euflavine. All of the trials were of poor quality. None of the trials found a significant difference between the groups with respect to the primary outcome of time to azoospermia. However, one trial found that the median number of ejaculations to azoospermia was significantly lower in the euflavine group compared to the water irrigation group. The one trial

  1. ( Atp9) gene between cytoplasmic male sterile line and its ...

    African Journals Online (AJOL)

    Administrator

    2011-09-07

    , the atp9 gene in soybeans was cloned from a soybean cytoplasmic male sterile line NJCMS2A and its maintainer line NJCMS2B. Sequence alignment was performed, and protein structures were analyzed and compared ...

  2. A genetic male sterile line developed by molecular marker-assisted ...

    African Journals Online (AJOL)

    use

    2011-12-05

    Dec 5, 2011 ... of male sterility, and methods of crossing, backcrossing and selfing were applied to breed the male sterility to male fertile line of Chinese cabbage Y02. The SCAR marker syau-scr04 which linked to the male sterility gene Ms, was applied in the selection of Ms gene. The new male sterile line GMS4 with.

  3. A genetic male sterile line developed by molecular marker-assisted ...

    African Journals Online (AJOL)

    A multiple allele inherited genetic male sterile line of Chinese cabbage 06s x 110 was used as the source of male sterility, and methods of crossing, backcrossing and selfing were applied to breed the male sterility to male fertile line of Chinese cabbage Y02. The SCAR marker syau-scr04 which linked to the male sterility ...

  4. Vasectomy occlusion techniques for male sterilization.

    Science.gov (United States)

    Cook, Lynley A; Van Vliet, Huib A A M; Lopez, Laureen M; Pun, Asha; Gallo, Maria F

    2014-03-30

    Vasectomy is an increasingly popular and effective family planning method. A variety of vasectomy techniques are used worldwide, including vas occlusion techniques (excision and ligation, thermal or electrocautery, and mechanical and chemical occlusion methods), as well as vasectomy with vas irrigation or with fascial interposition. Vasectomy guidelines largely rely on information from observational studies. Ideally, the choice of vasectomy techniques should be based on the evidence from randomized controlled trials (RCTs). The objective of this review was to compare the effectiveness, safety, acceptability and costs of vasectomy techniques for male sterilization. In February 2014, we updated the searches of CENTRAL, MEDLINE, POPLINE and LILACS. We looked for recent clinical trials in ClinicalTrials.gov and the International Clinical Trials Registry Platform. Previous searches also included EMBASE. For the initial review, we searched the reference lists of relevant articles and book chapters. We included RCTs comparing vasectomy techniques, which could include suture ligature, surgical clips, thermal or electrocautery, chemical occlusion, vas plugs, vas excision, open-ended vas, fascial interposition, or vas irrigation. We assessed all titles and abstracts located in the literature searches. Two reviewers independently extracted data from articles identified for inclusion. Outcome measures include contraceptive efficacy, safety, discontinuation, and acceptability. Peto odds ratios (OR) with 95% confidence intervals (CI) were used for dichotomous outcomes, such as azoospermia. The mean difference (MD) was used for the continuous variable of operating time. Six studies met the inclusion criteria. One trial compared vas occlusion with clips versus a conventional vasectomy technique. No difference was found in failure to reach azoospermia (no sperm detected). Three trials examined vasectomy with vas irrigation. Two studies looked at irrigation with water versus no

  5. 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

  6. Development of male sterility by silencing Bcp1 gene of Arabidopsis ...

    African Journals Online (AJOL)

    The development of male sterility is one of the most important steps in hybrid seed production. Several methods for the abortion of pollens based on conventional as well as genetic engineering are reported for the various crop species. Here we have investigated the use of RNA interference (RNAi) technology to silence a ...

  7. Assessing genetic variability in male sterile and low fertile citrus ...

    African Journals Online (AJOL)

    Yomi

    2012-01-24

    Jan 24, 2012 ... male sterile types, with old scattered resources; Iran has obvious diversity of citrus materials. ..... sexual reproduction and recombination are disabled in detecting such mutations in asexually propagated species. Therefore, it seems that in plants with asexual propagation system, inclusion of dominant ...

  8. Radio-sterilization effects on adult males of Glossina tachinoides ...

    African Journals Online (AJOL)

    Induced sterility of adult males of Glossina tachiniodes irradiated with gamma doses of 130, 150 and 160 Gy, respectively, in air was investigated. The flies were irradiated at horizontal distances of 50 cm and 70 cm, respectively from the Gamma Facility. The mean percentage insemination of spermathecae ranged between ...

  9. Insect population control by the sterile-male technique

    International Nuclear Information System (INIS)

    Lindquist, A.W.

    1963-01-01

    The successful use of the sterile male technique to eradicate the screw worm fly from the Southeastern part of the United States showed that a new biological method using radiation-sterilized insects could not only control but also eradicate harmful insect pests. A panel of experts met at the IAEA in Vienna in October 1962 to discuss the various aspects and applications of this new technique and to assess its usefulness and limitations. This report summarizes the panel proceedings. 42 refs, 18 figs, 1 tab

  10. Study on stable fly eradication by sterile-male technique

    International Nuclear Information System (INIS)

    Chung, K.H.; Ryu, J.; Kwon, S.H.

    1975-01-01

    This experiment was performed to investigate the X-ray sensitivities at the various stages of life cycle and to determine the sterillizing dose of stable fly, Stomoxys calcitrans(L). A dose of 300 rad caused about 50% mortality in 2-hour-old eggs as measured by egg hatch, and 100% mortality was obtained with a dose of 1 Krad. Sub-lethal dose (LDsub(50)) for the pupal age at irradiation. A significant reduction of egg hatch by 1.5% was observed when treated males with 3 Krad at pupal stage were mated to untreated virgin females. On the other hand, 100% sterility in females was resulted by Krad irradiation and oviposition was completely inhibited with 3 Krad. Thus, both sexes of stable fly could be sterilized with a dose of 4 Krad irradiated 50 3-5 days old pupae. (author)

  11. FUNCTIONAL MALE STERILITY AND ITS USE IN BREEDING OF VEGETABLE AND MELON CROPS

    Directory of Open Access Journals (Sweden)

    A. N. Bocharnikov

    2014-01-01

    Full Text Available The article describes the manifestation of functional male sterility and its importance in the breeding of melons. Utilization of functional male sterility allows solving the problem effective hybrid seed production.

  12. The sterile insect technique for controlling populations of Aedes albopictus (Diptera: Culicidae) on Reunion Island: mating vigour of sterilized males.

    Science.gov (United States)

    Oliva, Clelia F; Jacquet, Maxime; Gilles, Jeremie; Lemperiere, Guy; Maquart, Pierre-Olivier; Quilici, Serge; Schooneman, François; Vreysen, Marc J B; Boyer, Sebastien

    2012-01-01

    Reunion Island suffers from high densities of the chikungunya and dengue vector Aedes albopictus. The sterile insect technique (SIT) offers a promising strategy for mosquito-borne diseases prevention and control. For such a strategy to be effective, sterile males need to be competitive enough to fulfil their intended function by reducing wild mosquito populations in natura. We studied the effect of irradiation on sexual maturation and mating success of males, and compared the sexual competitiveness of sterile versus wild males in the presence of wild females in semi-field conditions. For all untreated or sterile males, sexual maturation was completed within 13 to 20 h post-emergence and some males were able to inseminate females when 15 h old. In the absence of competition, untreated and sterile males were able to inseminate the same number of virgin females during 48 h, in small laboratory cages: an average of 93% of females was inseminated no matter the treatment, the age of males, and the sex ratio. Daily mating success of single sterile males followed the same pattern as for untreated ones, although they inseminated significantly fewer females after the ninth day. The competitiveness index of sterile males in semi-field conditions was only 0.14 when they were released at 1-day old, but improved to 0.53 when the release occurred after a 5-day period in laboratory conditions. In SIT simulation experiments, a 5:1 sterile to wild male ratio allowed a two-fold reduction of the wild population's fertility. This suggests that sterile males could be sufficiently competitive to mate with wild females within the framework of an SIT component as part of an AW-IPM programme for suppressing a wild population of Ae. albopictus in Reunion Island. It will be of interest to minimise the pre-release period in controlled conditions to ensure a good competitiveness without increasing mass rearing costs.

  13. Components of competitiveness in sterile male boll weevils (Coleoptera: Curculionidae)

    International Nuclear Information System (INIS)

    Villavaso, E.J.; McGovern, W.L.; Wagner, T.L.; Willers, J.L.

    1998-01-01

    This study examines the relative importance of age at the time of irradiation on attractiveness, mating ability, sperm transfer, prior mating, and longevity as factors of competitiveness in sterile male boll weevil, Anthonomus grandis grandis Boheman. The amount of sperm transferred by irradiated males appeared to be the most important factor in competitiveness. More sperm was transferred by virgin males irradiated on day 5 than by virgin males irradiated on day 2, and males irradiated on day 5 had greater impact on egg hatch than those irradiated on day 2. The amount of sperm in spermathecae of females mated to virgin mates irradiated on day 5 was indistinguishable from that in females mated to virgin control males. Mating ability of males of all treatments was similar. Comparable numbers of boll weevils were captured in traps baited with males irradiated at 2 or 5 d during the first 4-5 d after irradiation, but thereafter, generally more weevils were captured in traps baited with males irradiated at 2 d or with control males. Attractiveness of males irradiated at 2 d was generally comparable to that of control males. More than 91% of irradiated males individually caged on cotton, Gossypium hirsutum L., plants lived for 10 d in the field, and 40% lived for 14 d; all individually caged control males lived 14 d. When released into cotton fields, however, the numbers of both irradiated and control males declined sharply over 14 d. Thus, the potential for an effective 2-wk life span in the field suggested by the caged study did not appear to apply to laboratory-reared weevils released into cotton fields

  14. Genetic studies on cytoplasmic male sterility in maize

    Energy Technology Data Exchange (ETDEWEB)

    Laughnan, J.R.

    1992-01-01

    Our research concerns the basic mechanisms of cytoplasmic male sterility (CMS) and fertility restoration in maize. The molecular determination of CMS is in the DNA of the mitochondria (mtDNA) but specific nuclear restorer-of-fertility (Rf) genes can overrule the male-sterile effect of the cytoplasm. Our approach to the study of the Rf genes is threefold. We are attempting to tag the cms-S Rf genes and the cms-T Rf2 gene with controlling elements (CEs). Since we have identified a number of spontaneous Rf genes for cms-S and have demonstrated that they are themselves transposable, we are also searching for cases in which an Rf gene is inserted into a wild-type gene. The other aspect of our research involves the nuclear control over the organization of the mitochondrial genome. We found that the changes in mtDNA organization upon cytoplasmic reversion to fertility were characteristic of the nuclear background in which the reversion event occurred. We have investigated whether these differences are a reflection of differences in the organization of the mtDNA genome before reversion.

  15. Transcriptional regulation of male-sterility in 7B-1 male-sterile tomato mutant

    Czech Academy of Sciences Publication Activity Database

    Omidvar, Vahid; Mohorianu, I.; Dalmay, T.; Zheng, Y.; Fei, Z.; Pucci, A.; Mazzucato, E.; Večeřová, R.; Sedlářová, M.; Fellner, Martin

    2017-01-01

    Roč. 12, č. 2 (2017), č. článku e0170715. E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : tapetum-degeneration-retardation * male reproductive development * early anther development * differential expression * lycopersicon-esculentum * stamenless-2 mutant * abscisic-acid * arabidopsis-thaliana * brassica-napus * cell-wall Subject RIV: EB - Gene tics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 2.806, year: 2016

  16. The effects of inbreeding and heat stress on male sterility in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Pedersen, Louise Dybdahl; Pedersen, Asger Roer; Bijlsma, Kuke

    2011-01-01

    in benign and stressful environments using Drosophila melanogaster as a model organism. Male sterility was compared in 21 inbred lines and five non-inbred control lines at 25.0 and 29.0 °C. The effect of inbreeding on sterility was significant only at 29.0 °C. This stress-induced increase in sterility...

  17. Puzzles in modern biology. I. Male sterility, failure reveals design [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Steven A. Frank

    2016-09-01

    Full Text Available Many human males produce dysfunctional sperm. Various plants frequently abort pollen. Hybrid matings often produce sterile males. Widespread male sterility is puzzling. Natural selection prunes reproductive failure. Puzzling failure implies something that we do not understand about how organisms are designed. Solving the puzzle reveals the hidden processes of design.

  18. Auxins reverse plant male sterility caused by high temperatures.

    Science.gov (United States)

    Sakata, Tadashi; Oshino, Takeshi; Miura, Shinya; Tomabechi, Mari; Tsunaga, Yuta; Higashitani, Nahoko; Miyazawa, Yutaka; Takahashi, Hideyuki; Watanabe, Masao; Higashitani, Atsushi

    2010-05-11

    With global warming, plant high temperature injury is becoming an increasingly serious problem. In wheat, barley, and various other commercially important crops, the early phase of anther development is especially susceptible to high temperatures. Activation of auxin biosynthesis with increased temperatures has been reported in certain plant tissues. In contrast, we here found that under high temperature conditions, endogenous auxin levels specifically decreased in the developing anthers of barley and Arabidopsis. In addition, expression of the YUCCA auxin biosynthesis genes was repressed by increasing temperatures. Application of auxin completely reversed male sterility in both plant species. These findings suggest that tissue-specific auxin reduction is the primary cause of high temperature injury, which leads to the abortion of pollen development. Thus, the application of auxin may help sustain steady yields of crops despite future climate change.

  19. Parthenogenesis maintains male sterility in a gynodioecious orchid.

    Science.gov (United States)

    Huang, Shuang-Quan; Lu, Yang; Chen, Ying-Zhuo; Luo, Yi-Bo; Delph, Lynda F

    2009-10-01

    The invasion of male-sterile (female) individuals into hermaphroditic populations, leading to gynodioecy, is common in flowering plants. Both theoretical and empirical studies have shown that as the frequency of females increases in a population, pollen limitation reduces seed production more in females than in hermaphrodites, leading to higher fitness for hermaphrodites and a consequent decrease in female frequency. Here we show that contrary to this expectation, females of the gynodioecious orchid Satyrium ciliatum are maintained only in populations that experience high pollen limitation caused by low pollinator service and high pollen herbivory. This species avoids the typical problem of pollen limitation for seed production and can therefore maintain high frequencies of females in pollen-limited populations because females produce more seeds than hermaphrodites via facultative parthenogenesis in the absence of pollinia. Our results therefore demonstrate that parthenogenesis is a novel mechanism favoring the maintenance of gynodioecy.

  20. Expression of a pathogen-induced cysteine protease (AdCP) in tapetum results in male sterility in transgenic tobacco.

    Science.gov (United States)

    Shukla, Pawan; Singh, Naveen Kumar; Kumar, Dilip; Vijayan, Sambasivam; Ahmed, Israr; Kirti, Pulugurtha Bharadwaja

    2014-06-01

    Usable male sterility systems have immense potential in developing hybrid varieties in crop plants, which can also be used as a biological safety containment to prevent horizontal transgene flow. Barnase-Barstar system developed earlier was the first approach to engineer male sterility in plants. In an analogous situation, we have evolved a system of inducing pollen abortion and male sterility in transgenic tobacco by expressing a plant gene coding for a protein with known developmental function in contrast to the Barnase-Barstar system, which deploys genes of prokaryotic origin, i.e., from Bacillus amyloliquefaciens. We have used a plant pathogen-induced gene, cysteine protease for inducing male sterility. This gene was identified in the wild peanut, Arachis diogoi differentially expressed when it was challenged with the late leaf spot pathogen, Phaeoisariopsis personata. Arachis diogoi cysteine protease (AdCP) was expressed under the strong tapetum-specific promoter (TA29) and tobacco transformants were generated. Morphological and histological analysis of AdCP transgenic plants showed ablated tapetum and complete pollen abortion in three transgenic lines. Furthermore, transcript analysis displayed the expression of cysteine protease in these male sterile lines and the expression of the protein was identified in western blot analysis using its polyclonal antibody raised in the rabbit system.

  1. Genetic analysis of male sterility genes in different A and B sorghum ...

    African Journals Online (AJOL)

    Hybrid seed production requires use of cytoplasmic male sterility (CMS). Without this system, hybrid seed production would not be economically feasible. There is, therefore, need for developing A and B sorghum lines, as an essential step for development of hybrid sorghum industry. A genetic study of male sterility in ...

  2. Mitochondrial DNA variation within P-type cytoplasmic male sterility of Plantago lanceolata L

    NARCIS (Netherlands)

    Groenendijk, C.F.M.; Sandbrink, J.M.; Van Brederode, J.; Van Damme, J.M.M.

    1997-01-01

    MtDNA restriction fragment polymorphisms were found between cytoplasmic male-sterility types P and R of Plantago lanceolata with the homologous probe pPl311 and maize mtDNA fragments derived from the regions of atp1, cox1 and cox2. No mtDNA differences were observed between male-sterile and restored

  3. A duplicated coxI gene is associated with cytoplasmic male sterility ...

    Indian Academy of Sciences (India)

    which have been implicated in male sterility (reviewed in. Keywords. Brassica juncea; coxI gene; cytoplasmic male sterility; somatic hybrid; transcript variation. ... drial recombination has led to duplication of coxI gene which appears to be associated with the CMS. Materials and methods. Plant material. B. juncea cv.

  4. Field performance of engineered male mosquitoes.

    Science.gov (United States)

    Harris, Angela F; Nimmo, Derric; McKemey, Andrew R; Kelly, Nick; Scaife, Sarah; Donnelly, Christl A; Beech, Camilla; Petrie, William D; Alphey, Luke

    2011-10-30

    Dengue is the most medically important arthropod-borne viral disease, with 50-100 million cases reported annually worldwide. As no licensed vaccine or dedicated therapy exists for dengue, the most promising strategies to control the disease involve targeting the predominant mosquito vector, Aedes aegypti. However, the current methods to do this are inadequate. Various approaches involving genetically engineered mosquitoes have been proposed, including the release of transgenic sterile males. However, the ability of laboratory-reared, engineered male mosquitoes to effectively compete with wild males in terms of finding and mating with wild females, which is critical to the success of these strategies, has remained untested. We report data from the first open-field trial involving a strain of engineered mosquito. We demonstrated that genetically modified male mosquitoes, released across 10 hectares for a 4-week period, mated successfully with wild females and fertilized their eggs. These findings suggest the feasibility of this technology to control dengue by suppressing field populations of A. aegypti.

  5. Comparative Transcriptomes Profiling of Photoperiod-sensitive Male Sterile Rice Nongken 58S During the Male Sterility Transition between Short-day and Long-day

    Directory of Open Access Journals (Sweden)

    Zhu Yingguo

    2011-09-01

    Full Text Available Abstract Background Photoperiod-sensitive genic male sterile (PGMS rice, Nongken 58S, was discovered in 1973. It has been widely used for the production of hybrid rice, and great achievements have been made in improving rice yields. However, the mechanism of the male sterility transition in PGMS rice remains to be determined. Results To investigate the transcriptome during the male sterility transition in PGMS rice, the transcriptome of Nongken 58S under short-day (SD and long-day (LD at the glume primordium differentiation and pistil/stamen primordium forming stages was compared. Seventy-three and 128 differentially expressed genes (DEGs were identified at the glume primordium differentiation and pistil/stamen primordium forming stages, respectively. Five and 22 genes were markedly up-regulated (≥ 5-fold, and two and five genes were considerably down-regulated (≥ 5-fold under SD during the male sterility transition. Gene ontology annotation and pathway analysis revealed that four biological processes and the circadian rhythms and the flowering pathways coordinately regulated the male sterility transition. Further quantitative PCR analysis demonstrated that the circadian rhythms of OsPRR1, OsPRR37, OsGI, Hd1, OsLHY and OsDof in leaves were obviously different between Nongken 58S and Nongken 58 under LD conditions. Moreover, both OsPRR37 and Hd1 in the inflorescence displayed differences between Nongken 58S and Nongken 58 under both LD and SD conditions. Conclusion The results presented here indicate that the transcriptome in Nongken 58S was significantly suppressed under LD conditions. Among these DEGs, the circadian rhythm and the flowering pathway were involved in the male sterility transition. Furthermore, these pathways were coordinately involved in the male sterility transition in PGMS rice.

  6. Sexual courtship of steriles males of Ceratitis Capitata (WIED) in SIT program

    International Nuclear Information System (INIS)

    Fadhel, Salma

    2008-01-01

    In the SIT programme, the success of sterile males to compete with the fertile males is an important parameter for assuring efficiency. In this study, two methods are tested to improve the sterile male quality: the first is the exposure of sterile males to different concentrations of Ginger Root Oil (GRO) (0, 20, 50 and 80 μl), the second is the exposure of males to different irradiation doses (80, 90, 100, 110, 120 and 145 Gy). The comparison of these methods depends to study of quality parameters (emergence, flight ability, survival) and courtship behaviour of sterile males (sperm production, mating competitiveness, sperm transfer). The 80μl concentration of GRO improves the mating competitiveness of males to compare with the Control (respectively: 68% and 46%). The 80 Gy irradiation dose assure the same result then the Control. (Author)

  7. Control of the wax moth Galleria mellonella L. (Lepidoptera: Pyralidae by the male sterile technique (MST

    Directory of Open Access Journals (Sweden)

    Jafari Reza

    2010-01-01

    Full Text Available In this study we examined the control of wax moth using the male sterile technique (MST with gamma-rays. To determine the safe and effective dosage of gamma-rays capable of sterilizing male pupae of the wax moth, male pupae were exposed to increasing single doses of gamma-rays (250, 300, 350 and 400 Gy. The release ratio of sterile to normal males was also studied in a similar experiment. Treatments included sterile males, normal males and virgin females at the following ratios: 1:1:1, 2:1:1, 3:1:1, 4:1:1 and 5:1:1. Possible parthenogenetic reproduction of this pest was also examined. The results showed that 350 Gy was the most effective dose capable of sterilizing the male pupae of the wax moth. The best release ratio was established at four sterile males, one normal male for each normal female (4:1:1. Also females were incapable of producing offspring without males.

  8. Evolvement of transgenic male-sterility and fertility-restoration system in rice for production of hybrid varieties.

    Science.gov (United States)

    Rao, Gundra Sivakrishna; Deveshwar, Priyanka; Sharma, Malini; Kapoor, Sanjay; Rao, Khareedu Venkateswara

    2018-01-01

    We have developed a unique male-sterility and fertility-restoration system in rice by combining Brassica napus cysteine-protease gene (BnCysP1) with anther-specific P12 promoter of rice for facilitating production of hybrid varieties. In diverse crop plants, male-sterility has been exploited as a useful approach for production of hybrid varieties to harness the benefits of hybrid vigour. The promoter region of Os12bglu38 gene of rice has been isolated from the developing panicles and was designated as P12. The promoter was fused with gusA reporter gene and was expressed in Arabidopsis and rice systems. Transgenic plants exhibited GUS activity in tapetal cells and pollen of the developing anthers indicating anther/pollen-specific expression of the promoter. For engineering nuclear male sterility, the coding region of Brassica napus cysteine protease1 (BnCysP1) was isolated from developing seeds and fused to P12 promoter. Transgenic rice plants obtained with P12-BnCysP1 failed to produce functional pollen grains. The F 1 seeds obtained from BnCysP1 male-sterile plants and untransformed controls showed 1:1 (tolerant:sensitive) ratio when germinated on the MS medium supplemented with phosphinothricin (5 mg/l), confirming that the male sterility has been successfully engineered in rice. For male fertility restoration, transgenic rice plants carrying BnCysP1Si silencing system were developed. The pollination of BnCysP1 male-sterile (female-fertile) plants with BnCysP1Si pollen resulted in normal grain filling. The F 1 seeds of BnCysP1 × BnCysP1Si when germinated on the MS basal medium containing PPT (5 mg/l) and hygromycin (70 mg/l) exhibited 1:1 (tolerant:sensitive) ratio and the tolerant plants invariably showed normal grain filling. The overall results clearly suggest that the customized male-sterility & fertility-restoration system can be exploited for quality hybrid seed production in various crops.

  9. Research to support sterile-male-release and genetic alteration techniques for sea lamprey control

    Science.gov (United States)

    Bergstedt, Roger A.; Twohey, Michael B.

    2007-01-01

    Integrated pest management of sea lampreys in the Laurentian Great Lakes has recently been enhanced by addition of a sterile-male-release program, and future developments in genetic approaches may lead to additional methods for reducing sea lamprey reproduction. We review the development, implementation, and evaluation of the sterile-male-release technique (SMRT) as it is being applied against sea lampreys in the Great Lakes, review the current understanding of SMRT efficacy, and identify additional research areas and topics that would increase either the efficacy of the SMRT or expand its geographic potential for application. Key areas for additional research are in the sterilization process, effects of skewed sex ratios on mating behavior, enhancing attractiveness of sterilized males, techniques for genetic alteration of sea lampreys, and sources of animals to enhance or expand the use of sterile lampreys.

  10. [The spotted sterile male--a new mutation of dominant spotting on the mouse chromosome 5].

    Science.gov (United States)

    Blandova, Z K; Vakhrusheva, M P; Malashenko, A M; Osipov, V V

    1986-06-01

    Spotted sterile male - a new mutation in mice is described (tentative symbol Ssm). White spotting on the belly, legs and tail as well as sterility in heterozygous males Ssm/+ of the B10.M strain are caused by autosomal semidominant gene Ssm. The gene is localized on the 5 chromosome: the frequency of recombination between Ssm and go is 13.6 +/- 1.6%; Ssm is closely linked to Wv. The diheterozygotes Ssm+/+Wv are darkeyed white sterile mice. The deficiency of spermatogenic epithelium cells, emptyness of seminiferous tubules as well as interstitial tissue overgrowing occurred in the testis in sterile males Ssm/+ of B10.M. The fertile hybrid males Ssm/+ are obtained in outcrossing of females Ssm/+ of B10.M with males of YT/Y, CBA/CaY, DBA/2JY, A.CA/Y strains.

  11. Field dispersal and survival of sterile medfly males aromatically treated with ginger root oil.

    Science.gov (United States)

    Paranhos, Beatriz Jordão; Papadopoulos, Nikos T; McInnis, Donald; Gava, Carlos; Lopes, Fabiana S C; Morelli, Renata; Malavasi, Aldo

    2010-04-01

    We studied the dispersal behavior and survival of sterile medfly males either treated or not with ginger root oil (GRO), in field conditions, in Petrolina-PE, northeast Brazil, from May 2006 to December 2007 in a sterile insect technique (SIT) program. The tsl strain Vienna 8 from the Ceratitis capitata Wied. (Diptera: Tephritidae), medfly, mass-rearing facility located in Juazeiro-BA, Brazil, was used. The results showed that sterile males either exposed or not to GRO exhibit similar dispersal behavior and postrelease survival. More than 60% of the sterile males, either treated or not treated with GRO, were recovered at a 25-m distance from the releasing point, approximately 20% at 50 m, and 5% in traps situated 100 m from the releasing point. Around 90% of the sterile males, exposed or not to GRO, were recovered 5 d after release of the sterile male individuals, whereas <1% were recovered after 11 d. Our results imply that ginger root oil can be used to treat sterile medfly males without interfering with their dispersal or survival in the field.

  12. Effects of gamma irradiation dose-rate on sterile male Aedesaegypti

    Science.gov (United States)

    Ernawan, Beni; Tambunan, Usman Sumo Friend; Sugoro, Irawan; Sasmita, Hadian Iman

    2017-06-01

    Aedesaegypti is the most important vector for dengue, yellow fever and Zika viruses. Considering its medical importance, vector population control program utilizing radiation-based sterile insect technique (SIT) is one of the potential methods for preventing and limiting the dispersal of these viruses. The present study was undertaken to evaluate the dose-rates effects of γ-sterilization on quality parameters of sterile males. Males Ae.aegypti at the pupal stage were sterilized by applying 70 Gyγ-rays in varies dose-rates, i.e. 0 (control), 300, 600, 900, 1200 and 1500Gy/h utilizing panoramic irradiator. Adult males that emerged from the pupal stage were assessed for their quality parameters, which are the percentage of emergence, longevity, sterility and mating competitiveness. The results herein indicate that there was no major effect of dose-rate on the percentage of emergence, the data showedthat there were no differences between irradiated males compared with control. Generally, the longevity of irradiated males was lower compared to control. The data also demonstrated that longevity was significantly increased at the dose-rate from 300 to 900Gy/h, then decreased at the dose-rate 900 to 1500 Gy/h. Sterility of irradiated maleswas significantly different compared to control, while there was no significantly different at dose rate 300 to 1500 Gy/h. Mating competitiveness of irradiated males was increased at the dose rate from 300 to 1200 Gy/h, then the value was decreased significantly at the dose rate 1500 Gy/h. The dose-rate effects of γ-sterilization were discussed in the context genetic vector control, in particular, the SIT. The results give information and contribute to better understanding towards γ-sterilization optimization and quality parameters of sterile male Ae. aegypti on SIT methods.

  13. RAPD analysis on male sterility mutant of Lilium asiatic hybrids 'pollyanna' induced by irradiation

    International Nuclear Information System (INIS)

    Jia Yuehui; Zhao Xiangyun; Zhang Kezhong; Huang Shangwu; Lu Changxun

    2005-01-01

    RAPD analysis of 80 random 10-mer primers on Lilium Asiatic hybrids 'pollyanna' and its 20 phenotype male sterility mutants induced by irradiation was carried out. Of the tested primers, 31 primers could produced ideal amplification bands on all materials, 4 primers generated stable different polymorphic bands among 9 mutants and 'pollyanna'. Different polymorphic bands of 7-18 were found among 9 mutants and 'pollyanna'. It was showed that 9 mutants were phenotype male sterility mutant of 'pollyanna'. (authors)

  14. Studies on the male sterility-fertility restoration system of AE. Kotschyi 19

    International Nuclear Information System (INIS)

    Cheng Junyuan; Sun Guoqing; Liu Luxiang; Zhao Linshu; Lu Xiuxia

    1996-01-01

    Sterile plants were obtained from the distant hybridization between Ae. Kotschyi 19 as the female parent and the Chinese Spring and T. yunnanense King as the male parent. Common wheat lines were used to testcross and backcross with the F 1 sterile plants successively. Male sterile line K-19 with Ae. Kotschyi cytoplasm and common wheat nucleus was bred. Over 10 K-19 MS lines were obtained. They are steady without monoploid. 7 restorers were obtained with the restoring ability from 88.2% to 96.9% according to the domestic method, from 116.4% to 150.4% according to the international method

  15. 'Gornooriahovska Kapia F1' - A new hybrid pepper variety based on radiation induced male sterility

    International Nuclear Information System (INIS)

    Daskalov, S.

    2001-01-01

    The female parent line 'Zlaten medal ms-8' was obtained by Daskalov as a gamma rays induced mutant of pepper (Capsicum annum L.). Dry seeds of the initial variety 'Zlaten medal' were irradiated with 135 Gy gamma rays and after screening of a large M 2 population (57,000 plants) 3 male sterile mutants were obtained. After an allelic test the genes responsible for male sterility were denoted as ms-6, ms-7, and ms-8. After many years of testing various male sterility sources the gene ms-8 proved to be the most suitable for hybrid seed production because it determines 100% male sterility, independent of the climatic condition or the genotype. The mutation causes the highest reduction of anthers, which allows easy distinction between male sterile and fertile flowers. The development of the mutant male sterile line Zlaten medal ms-8 is a good example of how mutation techniques can be very useful for adding or changing only one trait without altering the basic genotype

  16. Identification of miRNAs with potential roles in regulation of anther development and male-sterility in 7B-1 male-sterile tomato mutant

    Czech Academy of Sciences Publication Activity Database

    Omidvar, Vahid; Mohorianu, I.; Dalmay, T.; Fellner, Martin

    2015-01-01

    Roč. 16, OCT 28 (2015), s. 878 ISSN 1471-2164 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : 7B-1 mutation * Solanum lycopersicum * Male-sterility Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.867, year: 2015

  17. Acoustic Method for Testing the Quality of Sterilized Male Tsetse Flies Glossina Pallidipes

    International Nuclear Information System (INIS)

    Kratochvil, H.; Noll, A.; Bolldorf, J.; Parker, A.G.

    2012-01-01

    Tsetse flies are able to emit different acoustic signals. An acoustic method to test the quality of sterilized male tsetse flies was developed. Differences in the sound characteristics between males and females, between sterilized and unsterilized males, and between males sterilized in air and nitrogen, were determined. Also, the acoustic parameters (frequency, time, sound pressure level) of the sounds that are useful as criteria for quality control were determined. It was demonstrated that only the so-called 'feeding sounds' can be used as a quality criterion. Both sexes emitted feeding sounds while feeding on a host. These sounds were also used to find sexual partners, and had an effect on male copulation success. An acoustic sound analysis programme was developed; it automatically measured sound activity (only feeding sounds) under standard conditions (random sample, relative humidity, temperature, light intensity). (author)

  18. Analysis of plant height between male sterile plants obtained by space flight and male fertile plants in Maize

    International Nuclear Information System (INIS)

    Cao Moju; Huang Wenchao; Pan Guangtang; Rong Tingzhao; Zhu Yingguo

    2004-01-01

    F 2 fertility segregation population and the sister-cross fertility segregation population, which descended from the male sterile material, were analysed by their plant height of different growing stage between 2 populations of male sterile plants and male fertile plants. The plant height of different fertility plants come to the significance at 0.01 level in different stage through the whole growing period. The differences become more and more large with the development of plants, the maximum difference happens in adult stage. The increasing amount of different stage also shows significance at 0.01 level between two kinds of different fertility plants

  19. Inherited effects in F1 progeny of partially sterile male phthorimaea operculella (Lepidoptera: Gelechiidae)

    International Nuclear Information System (INIS)

    Makee, H.; Saour, G.

    1998-01-01

    Adult male phthorimaea operculella (Zeller), were exposed to sub sterilizing doses of gamma irradiation: 100, 150 and 200 Gy. Inherited effects in the F 1 , progeny of irradiated male parents were examined. Mean developmental time and the percentage mortality of the F 1 progeny, of each examined dose, were higher than that of the control group. Moreover, the sex ratio of the F 1 , progeny was skewed in favor of the males. Mean longevity, fecundity, and the percentage fertility of the F 1 progeny were lower than those of their parents and the control group. Mating ability and the frequency of mating of F 1 adults were similar to those of their partially sterile male parents and the control. The genetic basis of the F 1 characteristics has been discussed. The use of sub sterilizing doses of irradiation could be considered as an important component in a potato tuber moth control strategy. (author). 17 refs., 3 tabs

  20. DEVELOPMENT OF TOMATO HYBRIDS BASED ON FEMALE PARENTS FORMS WITH FUNCTIONAL MALE STERILITY

    Directory of Open Access Journals (Sweden)

    I. V. Uzun

    2016-01-01

    Full Text Available The rate of variability of functional male sterility (ps–2 depending on year of study, genotype and age of the plant is shown. The efficiency of the method of forced ejection of pollen from intact anthers to increase the degree of sterility is shown. The five tomato hybrids developed based on selected lines were submitted for the state variety trial of Moldova.

  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. Molecular-aided selection of male sterility for hybrid development in onion

    Science.gov (United States)

    Maintainer lines are used to seed propagate male-sterile lines for the development of hybrid-onion cultivars. Selection of maintainer lines is more efficient using molecular markers that distinguish cytoplasms and genotypes at the nuclear male-fertility restoration (Ms) locus. Onion cytoplasms can b...

  3. Sterility and Sexual Competitiveness of Tapachula-7 Anastrepha ludens Males Irradiated at Different Doses.

    Science.gov (United States)

    Orozco-Dávila, Dina; Adriano-Anaya, Maria de Lourdes; Quintero-Fong, Luis; Salvador-Figueroa, Miguel

    2015-01-01

    A genetic sexing strain of Anastrepha ludens (Loew), Tapachula-7, was developed by the Mexican Program Against Fruit Flies to produce and release only males in programs where the sterile insect technique (SIT) is applied. Currently, breeding are found at a massive scale, and it is necessary to determine the optimum irradiation dose that releases sterile males with minimum damage to their sexual competitiveness. Under laboratory and field conditions, we evaluated the effects of gamma irradiation at doses of 0, 20, 40, 60 and 80 Gy on the sexual competitiveness of males, the induction of sterility in wild females and offspring survivorship. The results of the study indicate that irradiation doses have a significant effect on the sexual behavior of males. A reduction of mating capacity was inversely proportional to the irradiation dose of males. It is estimated that a dose of 60 Gy can induce more than 99% sterility in wild females. In all treatments, the degree of offspring fertility was correlated with the irradiation dose of the parents. In conclusion, the results of the study indicate that a dose of 60 Gy can be applied in sterile insect technique release programs. The application of this dose in the new genetic sexing strain of A. ludens is discussed.

  4. Release of thiotepa sterilized males into caged populations of Aedes aegypti: life table analysis.

    Science.gov (United States)

    Gato, René; Companioni, Ariamys; Bruzón, Rosa Y; Menéndez, Zulema; González, Aileen; Rodríguez, Misladys

    2014-04-01

    Successful SIT trials against mosquitoes in the 1960-70s were achieved by sterilizing male mosquitoes using chemosterilants. Their use was discontinued after concerns were raised about the effect of residues on non-target organisms, although scant evidence has been published. Irradiation is an expensive process; chemosterilization could be an affordable option for implementing SIT programs in developing countries. We compare life table parameters of three Aedes aegypti populations comprising different ratios of thiotepa-treated and non-treated males in order to identify the impact on reproductive potential of the presence of sterile males. No difference was observed in the survival of the treated and untreated males. The release of thiotepa sterilized males into caged Ae. aegypti populations had no effect on death or survival probability of the individuals in the cages but the fecundity of females was significantly reduced, as evaluated by hatch rate and stable age structure parameters. The significant decreases in net reproduction rate, finite rate of natural increase and intrinsic rate of natural increase in populations including sterile males are sufficient to indicate that such populations would not be able to proliferate in natural conditions. This suggests that release of Ae. aegypti thiotepa-treated males could be effective in reducing the reproductive capability of the target population and consequently contribute to vector control. Copyright © 2013 International Atomic Energy Agency 2013. Published by Elsevier B.V. All rights reserved.

  5. 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)

  6. Marital Status and Female and Male Contraceptive Sterilization in the United States

    Science.gov (United States)

    Eeckhaut, Mieke Carine Wim

    2015-01-01

    Objective To examine female and male sterilization patterns in the United States based on marital status, and to determine if sociodemographic characteristics explain these sterilization patterns. Design Survival analysis of cross-sectional data from the female and male samples of the 2006–2010 National Survey of Family Growth (NSFG). Setting A trained female interviewer conducted in-home interviews. Patient(s) The 2006–2010 NSFG is designed to be representative of the U.S. civilian non-institutionalized population ages 15–44. Intervention(s) None. Main outcome measure(s) Vasectomy and tubal sterilization. Result(s) In the United States, vasectomy is the near exclusive domain of married men. Never- and ever-married single men and never-married cohabiting men had a low relative risk of vasectomy (RRs=0.1, 0.3, and 0.0, respectively) when compared to men in first marriages. Tubal sterilization was not limited to currently married, or even to ever-married women, though it was less common among never-married single women (RR=0.2) and more common among women in higher-order marriages (RR=1.8), as compared to women in first marriages. In contrast to vasectomy, differential use of tubal sterilization by marital status was driven in large part by differences in parity. Conclusion(s) This study shows that being unmarried at sterilization—an important risk factor for post-sterilization regret—was much more common among women than men. In addition to contributing to the predominance of female versus male sterilization, this pattern highlights the importance of educating women on the permanency of sterilization, as well as an opportunity to increase reliance on long-acting reversible contraceptive methods. PMID:25881875

  7. Molecular characterization of cytoplasmic male sterility (CMS) in perennial ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Islam, Md Shofiqul

    2011-01-01

    to increase biomass yield, improve nutritional value and tolerance towards abiotic and biotic stress. Cytoplasmic male sterility (CMS) is an efficient tool to control pollination for hybrid seed production. In order to identify the causative polymorphism of the CMS phenotype, a cytoplasmic male sterile plant......Perennial ryegrass (Lolium perenne L.) is a key grassland species in temperate climates. As an out breeding crop, ryegrass is currently being bred as population and synthetic families, thereby not fully exploiting the genetically available heterosis. Thus, hybrid breeding has the potential...... using 454 next-generation sequencing technology, resulting in approximately 800,000 high quality single reads. Here we report on the sequencing and the assembly of the mitochondrial genome from perennial ryegrass. Moreover, the assembly and annotation of the male-sterile and fertile mitochondrial...

  8. Genetic architecture of male sterility and segregation distortion in Drosophila pseudoobscura Bogota-USA hybrids.

    Science.gov (United States)

    Phadnis, Nitin

    2011-11-01

    Understanding the genetic basis of reproductive isolation between recently diverged species is a central problem in evolutionary genetics. Here, I present analyses of the genetic architecture underlying hybrid male sterility and segregation distortion between the Bogota and USA subspecies of Drosophila pseudoobscura. Previously, a single gene, Overdrive (Ovd), was shown to be necessary but not sufficient for both male sterility and segregation distortion in F(1) hybrids between these subspecies, requiring several interacting partner loci for full manifestation of hybrid phenomena. I map these partner loci separately on the Bogota X chromosome and USA autosomes using a combination of different mapping strategies. I find that hybrid sterility involves a single hybrid incompatibility of at least seven interacting partner genes that includes three large-effect loci. Segregation distortion involves three loci on the Bogota X chromosome and one locus on the autosomes. The genetic bases of hybrid sterility and segregation distortion are at least partially--but not completely--overlapping. My results lay the foundation for fine-mapping experiments to identify the complete set of genes that interact with Overdrive. While individual genes that cause hybrid sterility or inviability have been identified in a few cases, my analysis provides a comprehensive look at the genetic architecture of all components of a hybrid incompatibility underlying F(1) hybrid sterility. Such an analysis would likely be unfeasible for most species pairs due to their divergence time and emphasizes the importance of young species pairs such as the D. pseudoobscura subspecies studied here.

  9. De novo-based transcriptome profiling of male-sterile and fertile watermelon lines.

    Science.gov (United States)

    Rhee, Sun-Ju; Kwon, Taehyung; Seo, Minseok; Jang, Yoon Jeong; Sim, Tae Yong; Cho, Seoae; Han, Sang-Wook; Lee, Gung Pyo

    2017-01-01

    The whole-genome sequence of watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai), a valuable horticultural crop worldwide, was released in 2013. Here, we compared a de novo-based approach (DBA) to a reference-based approach (RBA) using RNA-seq data, to aid in efforts to improve the annotation of the watermelon reference genome and to obtain biological insight into male-sterility in watermelon. We applied these techniques to available data from two watermelon lines: the male-sterile line DAH3615-MS and the male-fertile line DAH3615. Using DBA, we newly annotated 855 watermelon transcripts, and found gene functional clusters predicted to be related to stimulus responses, nucleic acid binding, transmembrane transport, homeostasis, and Golgi/vesicles. Among the DBA-annotated transcripts, 138 de novo-exclusive differentially-expressed genes (DEDEGs) related to male sterility were detected. Out of 33 randomly selected newly annotated transcripts and DEDEGs, 32 were validated by RT-qPCR. This study demonstrates the usefulness and reliability of the de novo transcriptome assembly in watermelon, and provides new insights for researchers exploring transcriptional blueprints with regard to the male sterility.

  10. Expression of kenaf mitochondrial chimeric genes HM184 causes male sterility in transgenic tobacco plants.

    Science.gov (United States)

    Zhao, Yanhong; Liao, Xiaofang; Huang, Zhipeng; Chen, Peng; Zhou, Bujin; Liu, Dongmei; Kong, Xiangjun; Zhou, Ruiyang

    2015-08-01

    Chimeric genes resulting from the rearrangement of a mitochondrial genome were generally thought to be a causal factor in the occurrence of cytoplasmic male sterility (CMS). In the study, earlier we reported that identifying a 47 bp deletion at 3'- flanking of atp9 that was linked to male sterile cytoplasm in kenaf. The truncated fragment was fused with atp9, a mitochondrial transit signal (MTS) and/or GFP, comprised two chimeric genes MTS-HM184-GFP and MTS-HM184. The plant expression vector pBI121 containing chimeric genes were then introduced to tobacco plants by Agrobacterium-mediated T-DNA transformation. The result showed that certain transgenic plants were male sterility or semi-sterility, while some were not. The expression analysis further demonstrated that higher level of expression were showed in the sterility plants, while no expression or less expression in fertility plants, the levels of expression of semi-sterility were in between. And the sterile plant (containing MTS-HM184-GFP) had abnormal anther produced malformed/shriveled pollen grains stained negative that failed to germinate (0%), the corresponding fruits was shrunken, the semi-sterile plants having normal anther shape produced about 10-50% normal pollen grains, the corresponding fruits were not full, and the germination rate was 58%. Meanwhile these transgenic plants which altered on fertility were further analyzed in phenotype. As a result, the metamorphosis leaves were observed in the seedling stage, the plant height of transgenic plants was shorter than wild type. The growth duration of transgenic tobacco was delayed 30-45 days compared to the wild type. The copy numbers of target genes of transgenic tobacco were analyzed using the real-time quantitative method. The results showed that these transgenic plants targeting-expression in mitochondrial containing MTS-HM184-GFP had 1 copy and 2 copies, the other two plants containing MTS-HM184 both had 3 copies, but 0 copy in wild type. In

  11. Genetic architecture of autosome-mediated hybrid male sterility in Drosophila

    Energy Technology Data Exchange (ETDEWEB)

    Marin, I. [Stanford Univ., CA (United States)

    1996-04-01

    Several estimators have been developed for assesing the number of sterility factors in a chromosome based on the sizes of fertile and sterile introgressed fragments. Assuming that two factors are required for producing sterility, simulations show that one of these, twice the inverse of the relative size of the largest fertile fragment, provides good average approximations when as few as five fertile fragments are analyzed. The estimators have been used for deducing the number of factors from previous data on several pairs of species. A particular result contrasts with the authors` interpretations: instead of the high number of sterility factors suggested, only a few per autosome are estimated in both reciprocal crosses involving Drosophila buzzatii and D. koepferae. It has been possible to map these factors, between three and six per chromosome, in the autosomes 3 and 4 of these species. Out of 203 introgressions of different fragments or combinations of fragments, the outcome of at least 192 is explained by the mapped zones. These results suggest that autosome-mediated sterility in the male hybrids of these species is mediated by a few epistatic factors, similarly to X-mediated sterility in the hybrids of other Drosophila species. 48 refs., 5 tabs.

  12. Non-coding RNA may be associated with cytoplasmic male sterility in Silene vulgaris

    Czech Academy of Sciences Publication Activity Database

    Stone, James D.; Koloušková, Pavla; Sloan, D.B.; Štorchová, Helena

    2017-01-01

    Roč. 68, č. 7 (2017), s. 1599-1612 ISSN 0022-0957 R&D Projects: GA ČR(CZ) GA16-09220S Institutional support: RVO:61389030 Keywords : Cytoplasmic male sterility * Editing * Mitochondrion * Non-coding RNA * Silene vulgaris * Splicing * Transcriptome Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 5.830, year: 2016

  13. A duplicated coxI gene is associated with cytoplasmic male sterility ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 86; Issue 2. A duplicated coxI gene is associated with cytoplasmic male sterility in an alloplasmic Brassica juncea line derived from somatic hybridization with Diplotaxis catholica. Aruna Pathania Rajesh Kumar V. Dinesh Kumar Ashutosh K. K. Dwivedi P. B. Kirti P. Prakash V. L. ...

  14. Cytoplasmic male sterility in Petunia hybrida : a structural and histochemical analysis

    NARCIS (Netherlands)

    Bino, R.J.

    1986-01-01

    This thesis presents an analysis of the structural and histochemical aspects of cytoplasmic male sterility (cms) in Petuniahybrida . In petunia and in other crops, cms is the most commonly used tool for hybrid seed production. Application of the trait

  15. Linkage mapping of a dominant male sterility gene Ms-cd1 in Brassica oleracea

    NARCIS (Netherlands)

    Wang, X.; Lou, P.; Bonnema, A.B.; Yang, Boujun; He, H.; Zhang, Y.; Fang, Z.

    2005-01-01

    The dominant male sterility gene Ms-cd1 (c, cabbage; d, dominant) was identified as a spontaneous mutation in the spring cabbage line 79-399-3. The Ms-cd1 gene is successfully applied in hybrid seed production of several Brassica oleracea cultivars in China. Amplified fragment length polymorphism

  16. Breeding and characterization of homokaryotic heteroplasmic male sterile lines in rice (oryza sativa)

    International Nuclear Information System (INIS)

    Mei, Q.; Zhou, X.; Liu, C.

    2011-01-01

    Twelve different Cytoplasmic Male-Sterile (CMS) lines were crossed with 18 rice varieties. From the hybrid with japonica rice Nongken 58, twelve homokaryotic-heteroplasmic male sterile lines were developed in B7F1 after successive back crossing and selection for stable male sterility and desirable agronomic traits such as flowering habit and high out crossing rate. The experimental results demonstrated that expression of the CMS factors were influenced by the corresponding nuclear genes. Three pollen abortion types, including the typical, the spherical and the stained abortion, were observed in the homokaryotic-heteroplasmic male sterile lines. Formation of the aborted pollen grains was influenced by the interaction among specific cytoplasmic and the corresponding nuclear genes. As the CMS carriers, these homokaryotic-heteroplasmic lines will have significant impact on the utilization of multiple types of CMS in hybrid rice breeding. What is more important is that these CMS lines are the invaluable materials for the investigation of the molecular mechanism of CMS formation in rice. (author)

  17. A dominant, recombination-defective allele of Dmc1 causing male-specific sterility

    NARCIS (Netherlands)

    Bannister, Laura A.; Pezza, Roberto J.; Donaldson, Janet R.; de Rooij, Dirk G.; Schimenti, Kerry J.; Camerini-Otero, R. Daniel; Schimenti, John C.

    2007-01-01

    DMC1 is a meiosis-specific homolog of bacterial RecA and eukaryotic RAD51 that can catalyze homologous DNA strand invasion and D-loop formation in vitro. DMC1-deficient mice and yeast are sterile due to defective meiotic recombination and chromosome synapsis. The authors identified a male dominant

  18. Molecular analysis of a new cytoplasmic male sterile genotype in sunflower

    NARCIS (Netherlands)

    Spassova, Mariana; Christov, Michail; Bohorova, Natasha; Petrov, Peter; Dudov, Kalin; Atanassov, Atanas; Nijkamp, H. John J.; Hille, Jaques

    1992-01-01

    Mitochondrial DNA from 1 fertile and 6 cytoplasmic male sterile (CMS) sunflower genotypes was studied. The CMS genotypes had been obtained either by specific crosses between different Helianthus species or by mutagenesis. CMS-associated restriction fragment length polymorphisms (RFLPs) were found in

  19. Transcriptome profiling of differentially expressed genes in floral buds and flowers of male sterile and fertile lines in watermelon.

    Science.gov (United States)

    Rhee, Sun-Ju; Seo, Minseok; Jang, Yoon-Jeong; Cho, Seoae; Lee, Gung Pyo

    2015-11-09

    Male sterility is an important mechanism for the production of hybrid seeds in watermelon. Although fruit development has been studied extensively in watermelon, there are no reports on gene expression in floral organs. In this study, RNA-sequencing (RNA-seq) was performed in two near-isogenic watermelon lines (genic male sterile [GMS] line, DAH3615-MS and male fertile line, DAH3615) to identify the differentially expressed genes (DEGs) related to male sterility. DEG analysis showed that 1259 genes were significantly associated with male sterility at a FDR P-value of watermelon. This analysis revealed essential genes responsible for stamen development, including pollen development and pollen tube elongation, and allowed their functional classification. These results provided new information on global mechanisms related to male sterility in watermelon.

  20. Male perceptions on female sterilization: a community-based study in rural Central India.

    Science.gov (United States)

    Char, Arundhati; Saavala, Minna; Kulmala, Teija

    2009-09-01

    Use of modern contraceptive methods has increased fourfold in India since the 1970s, characterized by a predominance of female sterilization. There has been considerable investigation about women's choice of female sterilization, but little from the male perspective. Seven focus group discussions were conducted among 58 men currently married to women aged 15-45, followed by a cross-sectional survey among 793 men currently married to same-aged women. Bivariate analysis was used for the survey data, and content analysis was used for the qualitative data. Men's primary source of reproductive health information was mass media, although they expressed interest in getting information through discussion with knowledgeable sources. Men understood family planning and contraception to be two separate issues: Men viewed "family planning" as synonymous with female sterilization, whereas they saw "contraception" as referring to spacing methods, knowledge of which was limited. Thirty-four percent of men reported that their wives had been sterilized; 79% of men who did not rely on any permanent method said they wanted their wives to be sterilized. In focus group discussions, most men reported themselves as their family's sole decision maker about reproductive health; however, only one-third of survey respondents did so. Men are interested in acquiring family planning information, but lack knowledge about available information sources, which hampers their ability to make informed family planning choices. Family planning service providers and program planners need to be aware of males' knowledge and perceptions pertaining to family planning, and make appropriate modifications to communication strategies.

  1. Potential for control of Cadra cautella (Walker) by release of fully or partially sterile males

    International Nuclear Information System (INIS)

    Brower, J.H.; Tilton, E.W.

    1975-01-01

    Modifications of the sterile-male release technique appear to offer promise for the control of post-harvest lepidopteran pest populations within storage structures. Theoretical models of release strategies for Cadra cautella showed that each method has an 'ideal' flooding ratio. This ratio represents the best balance between extinction in a few generations and minimization of the total number of insects released. From data reported concerning the population dynamics of Cadra cautella in the field an ideal flooding ratio for fully sterile (S) males to fertile (F) males of 97:1 would achieve extinction in 3 generations. Total numbers of males released per 100 native insects that would be needed to achieve extinction at these flooding ratios would be 14,850, 14,900 and 18,500, respectively. (author)

  2. 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

  3. Characterisation and expression of the mitochondrial genome of a new type of cytoplasmic male-sterile sunflower

    NARCIS (Netherlands)

    Spassova, Mariana; Moneger, Françoise; Leaver, Christopher J.; Petrov, Peter; Atanassov, Atanas; Nijkamp, H. John J.; Hille, Jacques

    1994-01-01

    A new cytoplasmic male sterile sunflower, CMS3, was characterised in relation to the Petiolaris (PET1) cytoplasmic male-sterile sunflower, CMS89. Southern blot analysis showed that the mitochondrial genome of CMS3 contains unique rearrangements in at least five loci (atp6, atp9, atpA, nad1 + 5 and

  4. Effects of x-ray irradiation on male navel orangeworm (Lepidoptera: Pyralidae) on mating, fecundity, fertility, and inherited sterility

    Science.gov (United States)

    Male adult navel orangeworm, Amyelois transitella, were irradiated using a laboratory x-ray emitter to determine the dose needed to achieve complete egg sterility of mated female moths and inherited egg sterility of F1 generation. Adult male A. transitella were irradiated in a series of two experime...

  5. Genetic architecture of hybrid male sterility in Drosophila: analysis of intraspecies variation for interspecies isolation.

    Directory of Open Access Journals (Sweden)

    Laura K Reed

    Full Text Available BACKGROUND: The genetic basis of postzygotic isolation is a central puzzle in evolutionary biology. Evolutionary forces causing hybrid sterility or inviability act on the responsible genes while they still are polymorphic, thus we have to study these traits as they arise, before isolation is complete. METHODOLOGY/PRINCIPAL FINDINGS: Isofemale strains of D. mojavensis vary significantly in their production of sterile F(1 sons when females are crossed to D. arizonae males. We took advantage of the intraspecific polymorphism, in a novel design, to perform quantitative trait locus (QTL mapping analyses directly on F(1 hybrid male sterility itself. We found that the genetic architecture of the polymorphism for hybrid male sterility (HMS in the F(1 is complex, involving multiple QTL, epistasis, and cytoplasmic effects. CONCLUSIONS/SIGNIFICANCE: The role of extensive intraspecific polymorphism, multiple QTL, and epistatic interactions in HMS in this young species pair shows that HMS is arising as a complex trait in this system. Directional selection alone would be unlikely to maintain polymorphism at multiple loci, thus we hypothesize that directional selection is unlikely to be the only evolutionary force influencing postzygotic isolation.

  6. Single-layer tungsten oxide as intelligent photo-responsive nanoagents for permanent male sterilization.

    Science.gov (United States)

    Liu, Zhen; Liu, Xianjun; Ran, Xiang; Ju, Enguo; Ren, Jinsong; Qu, Xiaogang

    2015-11-01

    Permanent male sterilization has been recognized as useful tools for the development of neuter experimental animals and fattening livestock, as well as efficient control of pet overpopulation. Traditional routes such as surgical ways, chemical injections, and anti-fertility vaccines have addressed these crucial problems with idea outcomes. However, these routes usually bring out serious pain and infection towards animals, as well as induce long-term adverse reaction and immune suppression. Thus, a convenient, but non-surgical strategy for male sterilization under a mild manner is highly desirable. Here, for the first time, we demonstrate a novel platform for male sterilization by using single-layer WO2.72 nanosheets as smart photo-responsive sterilants. Upon a 980 nm irradiation, these nanoagents can possess intrinsic NIR-induced hyperthermia and sensitize the formation of singlet oxygen due to the cooperation of photothermal and photodynamic effects. Mechanism of cellular injury can be attributed to the denaturation of protein and apoptosis-related death. Moreover, long-term toxicity and possible metabolism route after testicular injection are discussed, indicating the neglectable systemic toxicity and high bio-compatibility of our nanoagents. Overall, our strategy can extremely overcome the shortcomings in various routine routes and suggest the new biological application of nanomaterials. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Gamma irradiation of the western cherry fruit fly for the sterile male control technique

    International Nuclear Information System (INIS)

    Brown, R.D.

    1978-01-01

    The western cherry fruit fly, Rhagoletis indifferens Curran, was studied to determine the suitability of the sterile insect technique for its control. The western cherry fruit fly is strictly univoltine; only 1.1 percent adult emergence occurred without chilling under laboratory conditions at 26.7 0 C and photoperiod of 19L:5D. Percent emergence increased with longer periods of chilling. Synchroniztion of emergence was maximized after about 200 days at 3 0 C. Time to emergence decreased with increasing days of chilling; after a minimum of 200 days of chilling at 3 0 C, flies emerged after an average of 26 days at 26.7 0 C. Flies exhibited a pre-mating and pre-oviposition period in the laboratory, during which flies spent little time on cherries. The presence of a male pheromone was demonstrated. Sterile males were more competitive in ratios of 1:1 and 4:1 than 8:1 in laboratory cages: the total number of matings was about the same with 8:1 ratios as with 4:1. Females were less receptive to males after several matings, so that with a constant number of females, the number of matings by unirradiated males was reduced in the presence of sterile males. Irradiated males mated about 80 percent as frequently as normal males. Males irradiated as pupae were less than half as competitive as males irradiated as adults. Sperm from the last-mated male had precedence, but some mixing of the sperm occurred. Field cage studies showed about 94 percent reduction in infestation with 20:1 sterile to normal male ratios. The low economic threshold, the small dispersal capability, and favorable radiobiology of the flies make this insect an attractive candidate for the sterile insect technique. The technique may be used alone, or in an integrated control program in combination with chemicals. Post-harvest release of flies would efficiently prevent build-up of the population in the remnant of cherries left after mechanical harvesting

  8. 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

  9. Semiochemical mediated enhancement of males to complement sterile insect technique in management of the tephritid pest Bactrocera tryoni (Froggatt).

    Science.gov (United States)

    Khan, Mohammed Abul Monjur; Manoukis, Nicholas C; Osborne, Terry; Barchia, Idris M; Gurr, Geoff M; Reynolds, Olivia L

    2017-10-17

    Queensland fruit fly, Bactrocera tryoni (Froggatt), is the most significant pest of Australia's $9 billion horticulture industry. The sterile insect technique (SIT) and cue-lure (a synthetic analogue of raspberry ketone (RK))-based male annihilation technique (MAT) are two of the most effective management tools against this pest. However, combining these two approaches is considered incompatible as MAT kills sterile and 'wild' males indiscriminately. In the present study we tested the effect of pre-release feeding of B. tryoni on RK on their post-release survival and response to MAT in field cages and in a commercial orchard. In both settings, survival was higher for RK supplemented adults compared to control (i.e. RK denied) adults. A lower number of RK supplemented sterile males were recaptured in MAT baited traps in both the field cages and orchard trials compared to RK denied sterile males. The advantage of this novel "male replacement" approach (relatively selective mortality of wild males at lure-baited traps while simultaneously releasing sterile males) is increasing the ratio of sterile to wild males in the field population, with potential for reducing the number of sterile males to be released.

  10. Eradication of melon flies (Dacus cucurbitae) of the Kume Island using sterile males under field conditions

    International Nuclear Information System (INIS)

    Iwahashi, Osamu

    1984-01-01

    On the assumption that there were approximately 250,000 normal melon flies (Dacus cucurbitae) in the Kume Island as of February 1975, sterile flies have been released into the field. A previous experiment undertaken in the Kudaka Island revealed that the number of sterile pupae (with 7 kR of irradiation) should be ten times larger than that of normal flies for obtaining satisfactory results. 2,500,000 or more pupae per week were required for the purpose of eradication in the Kume Island. Satisfactory results were not obtained because of the limited production of sterile flies (1,000,000 per week). Since a mass-production facility was established in Autumn 1975, the weekly release of 1,500,000 - 2,000,000 flies became possible. Since May 1976, 3,500,000 - 4,000,000 sterile flies began to be released weekly. As a result, the rate of hatchability of eggs decreased with increasing the proportion of sterile flies to normal flies. The number of female flies caught in monitor traps also suggested that there were few normal male flies. The incidence of injuried fruits of Melothria japonica Maxim. Okinawa began to decrease remarkably from May 1976. None of 156,000 fruits were injuried between October 1976 and September 1977. (Namekawa, K.)

  11. 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

  12. Whole Mitochondrial Genome Sequencing and Re-Examination of a Cytoplasmic Male Sterility-Associated Gene in Boro-Taichung-Type Cytoplasmic Male Sterile Rice.

    Science.gov (United States)

    Kazama, Tomohiko; Toriyama, Kinya

    2016-01-01

    Nuclear genome substitutions between subspecies can lead to cytoplasmic male sterility (CMS) through incompatibility between nuclear and mitochondrial genomes. Boro-Taichung (BT)-type CMS rice was obtained by substituting the nuclear genome of Oryza sativa subsp. indica cultivar Chinsurah Boro II with that of Oryza sativa subsp. japonica cultivar Taichung 65. In BT-type CMS rice, the mitochondrial gene orf79 is associated with male sterility. A complete sequence of the Boro-type mitochondrial genome responsible for BT-type CMS has not been determined to date. Here, we used pyrosequencing to construct the Boro-type mitochondrial genome. The contiguous sequences were assembled into five circular DNA molecules, four of which could be connected into a single circle. The two resulting subgenomic circles were unable to form a reliable master circle, as recombination between them was scarcely detected. We also found an unequal abundance of DNA molecules for the two loci of atp6. These results indicate the presence of multi-partite DNA molecules in the Boro-type mitochondrial genome. Expression patterns were investigated for Boro-type mitochondria-specific orfs, which were not found in the mitochondria from the standard japonica cultivar Nipponbare. Restorer of fertility 1 (RF1)-dependent RNA processing has been observed in orf79-containing RNA but was not detected in other Boro-type mitochondria-specific orfs, supporting the conclusion that orf79 is a unique CMS-associated gene in Boro-type mitochondria.

  13. Epistasis among Drosophila persimilis factors conferring hybrid male sterility with D. pseudoobscura bogotana.

    Directory of Open Access Journals (Sweden)

    Audrey S Chang

    2010-10-01

    Full Text Available The Bateson-Dobzhansky-Muller model posits that hybrid incompatibilities result from genetic changes that accumulate during population divergence. Indeed, much effort in recent years has been devoted to identifying genes associated with hybrid incompatibilities, often with limited success, suggesting that hybrid sterility and inviability are frequently caused by complex interactions between multiple loci and not by single or a small number of gene pairs. Our previous study showed that the nature of epistasis between sterility-conferring QTL in the Drosophila persimilis-D. pseudoobscura bogotana species pair is highly specific. Here, we further dissect one of the three QTL underlying hybrid male sterility between these species and provide evidence for multiple factors within this QTL. This result indicates that the number of loci thought to contribute to hybrid dysfunction may have been underestimated, and we discuss how linkage and complex epistasis may be characteristic of the genetics of hybrid incompatibilities. We further pinpoint the location of one locus that confers hybrid male sterility when homozygous, dubbed "mule-like", to roughly 250 kilobases.

  14. Comparative transcriptome profiling of the fertile and sterile flower buds of a dominant genic male sterile line in sesame (Sesamum indicum L.).

    Science.gov (United States)

    Liu, Hongyan; Tan, Mingpu; Yu, Haijuan; Li, Liang; Zhou, Fang; Yang, Minmin; Zhou, Ting; Zhao, Yingzhong

    2016-11-10

    Sesame (Sesamum indicum L.) is a globally important oilseed crop with highly-valued oil. Strong hybrid vigor is frequently observed within this crop, which can be exploited by the means of genic male sterility (GMS). We have previously developed a dominant GMS (DGMS) line W1098A that has great potential for the breeding of F 1 hybrids. Although it has been genetically and anatomically characterized, the underlying molecular mechanism for male sterility remains unclear and therefore limits the full utilization of such GMS line. In this study, RNA-seq based transcriptome profiling was carried out in two near-isogenic DGMS lines (W1098A and its fertile counterpart, W1098B) to identify differentially expressed genes (DEGs) related to male sterility. A total of 1,502 significant DEGs were detected, among which 751 were up-regulated and 751 were down-regulated in sterile flower buds. A number of DEGs were implicated in both ethylene and JA synthesis & signaling pathway; the expression of which were either up- or down-regulated in the sterile buds, respectively. Moreover, the majority of NAC and WRKY transcription factors implicated from the DEGs were up-regulated in sterile buds. By querying the Plant Male Reproduction Database, 49 sesame homologous genes were obtained; several of these encode transcription factors (bHLH089, MYB99, and AMS) that showed reduced expression in sterile buds, thus implying the possible role in specifying or determining tapetal fate and development. The predicted effect of allelic variants on the function of their corresponding DEGs highlighted several Insertions/Deletions (InDels), which might be responsible for the phenotype of sterility/fertility in DGMS lines. The present comparative transcriptome study suggested that both hormone signaling pathway and transcription factors control the male sterility of DGMS in sesame. The results also revealed that several InDels located in DEGs prone to cause loss of function, which might contribute to

  15. Identification of novel putative causative genes and genetic marker for male sterility in Japanese cedar (Cryptomeria japonica D.Don).

    Science.gov (United States)

    Mishima, Kentaro; Hirao, Tomonori; Tsubomura, Miyoko; Tamura, Miho; Kurita, Manabu; Nose, Mine; Hanaoka, So; Takahashi, Makoto; Watanabe, Atsushi

    2018-04-23

    Japanese cedar (Cryptomeria japonica) is an important tree for Japanese forestry. Male-sterile marker development in Japanese cedar would facilitate selection of male-sterile plus trees, addressing the widespread social problem of pollinosis and facilitating the identification of heterozygotes, which are useful for breeding. This study used next-generation sequencing for single-nucleotide polymorphism discovery in libraries constructed from several organs, including male-sterile and male-fertile strobili. The single-nucleotide polymorphisms obtained were used to construct a high-density linkage map, which enabled identification of a locus on linkage group 9 strongly correlated with male-sterile trait. Expressed sequence tags corresponding to 11 marker loci from 5 isotigs were associated with this locus within 33.4-34.5 cM. These marker loci explained 100% of the phenotypic variation. Several homologs of these sequences are associated with male sterility in rice or Arabidopsis, including a pre-mRNA splicing factor, a DEAD-box protein, a glycosyl hydrolase, and a galactosyltransferase. These proteins are thus candidates for the causal male-sterile gene at the ms-1 locus. After we used a SNaPshot assay to develop markers for marker-assisted selection (MAS), we tested F 2 progeny between male-sterile and wild-type plus trees to validate the markers and extrapolated the testing to a larger plus-tree population. We found that two developed from one of the candidates for the causal gene were suitable for MAS. More than half of the ESTs and SNPs we collected were new, enlarging the genomic basis for genetic research on Japanese cedar. We developed two SNP markers aimed at MAS that distinguished individuals carrying the male-sterile trait with 100% accuracy, as well as individuals heterozygous at the male-sterile locus, even outside the mapping population. These markers should enable practical MAS for conifer breeding.

  16. Programmed cell death promotes male sterility in the functional dioecious Opuntia stenopetala (Cactaceae).

    Science.gov (United States)

    Flores-Rentería, Lluvia; Orozco-Arroyo, Gregorio; Cruz-García, Felipe; García-Campusano, Florencia; Alfaro, Isabel; Vázquez-Santana, Sonia

    2013-09-01

    The sexual separation in dioecious species has interested biologists for decades; however, the cellular mechanism leading to unisexuality has been poorly understood. In this study, the cellular changes that lead to male sterility in the functionally dioecious cactus, Opuntia stenopetala, are described. The spatial and temporal patterns of programmed cell death (PCD) were determined in the anthers of male and female flowers using scanning electron microscopy analysis and histological observations, focusing attention on the transition from bisexual to unisexual development. In addition, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling assays were used as an indicator of DNA fragmentation to corroborate PCD. PCD was detected in anthers of both female and male flowers, but their patterns differed in time and space. Functionally male individuals developed viable pollen, and normal development involved PCD on each layer of the anther wall, which occurred progressively from the inner (tapetum) to the outer layer (epidermis). Conversely, functional female individuals aborted anthers by premature and displaced PCD. In anthers of female flowers, the first signs of PCD, such as a nucleus with irregular shape, fragmented and condensed chromatin, high vacuolization and condensed cytoplasm, occurred at the microspore mother cell stage. Later these features were observed simultaneously in all anther wall layers, connective tissue and filament. Neither pollen formation nor anther dehiscence was detected in female flowers of O. stenopetala due to total anther disruption. Temporal and spatial changes in the patterns of PCD are responsible for male sterility of female flowers in O. stenopetala. Male fertility requires the co-ordination of different events, which, when altered, can lead to male sterility and to functionally unisexual individuals. PCD could be a widespread mechanism in the determination of functionally dioecious species.

  17. Advances in insect population control by the sterile-male technique

    International Nuclear Information System (INIS)

    1965-01-01

    The sterile male technique has been successfully used in the control or eradication of at least eight species of insects in experimental or field trials. In view of the importance of the method the IAEA convened a Panel of experts in July 1964 to review the progress made in research on the application of the technique and to suggest future actions. The findings of the Panel are published in this Technical Report. 52 refs, 10 figs, 10 tabs

  18. The role of non-coding RNAs in cytoplasmic male sterility in flowering plants

    Czech Academy of Sciences Publication Activity Database

    Štorchová, Helena

    2017-01-01

    Roč. 18, č. 11 (2017), č. článku 2429. E-ISSN 1422-0067 R&D Projects: GA ČR GA16-09220S Institutional support: RVO:61389030 Keywords : Cytoplasmic male sterility * Gene expression * Global transcriptome * Non-coding RNA * Pollen development Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 3.226, year: 2016

  19. Sex ratio meiotic drive as a plausible evolutionary mechanism for hybrid male sterility.

    Directory of Open Access Journals (Sweden)

    Linbin Zhang

    2015-03-01

    Full Text Available Biological diversity on Earth depends on the multiplication of species or speciation, which is the evolution of reproductive isolation such as hybrid sterility between two new species. An unsolved puzzle is the exact mechanism(s that causes two genomes to diverge from their common ancestor so that some divergent genes no longer function properly in the hybrids. Here we report genetic analyses of divergent genes controlling male fertility and sex ratio in two very young fruitfly species, Drosophila albomicans and D. nasuta. A majority of the genetic divergence for both traits is mapped to the same regions by quantitative trait loci mappings. With introgressions, six major loci are found to contribute to both traits. This genetic colocalization implicates that genes for hybrid male sterility have evolved primarily for controlling sex ratio. We propose that genetic conflicts over sex ratio may operate as a perpetual dynamo for genome divergence. This particular evolutionary mechanism may largely contribute to the rapid evolution of hybrid male sterility and the disproportionate enrichment of its underlying genes on the X chromosome--two patterns widely observed across animals.

  20. A pentatricopeptide repeat protein restores nap cytoplasmic male sterility in Brassica napus.

    Science.gov (United States)

    Liu, Zhi; Dong, Faming; Wang, Xiang; Wang, Tao; Su, Rui; Hong, Dengfeng; Yang, Guangsheng

    2017-07-10

    Two forms of male-sterile cytoplasm, designated nap and pol, are found in the oilseed rape species, Brassica napus. The nap cytoplasm is observed in most B. napus varieties, and it confers male sterility on a limited number of cultivars that lack the corresponding restorer gene, Rfn. In the present study, using linkage analysis in combination with 5652 BC1 progeny derived from a cross between a nap cytoplasmic male sterility (CMS) line 181A and a restorer line H5, we delimited the Rfn gene to a 10.5 kb region on chromosome A09, which contained three putative ORFs. Complementation by transformation rescue revealed that the introduction of ORF2, which encodes a pentatricopeptide repeat (PPR) protein, resulted in the recovery of fertility of nap CMS plants. Expression analysis suggested that the Rfn was highly expressed in flower buds and it was preferentially expressed in the tapetum and meiocytes during anther development. Further RNA gel blots and immunodetection suggested that the Rfn gene may play a complicated role in restoring the nap CMS. Our work laid the foundation for dissecting the molecular basis of CMS fertility restoration and the nuclear-mitochondrial interactions in CMS/Rf systems. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  1. 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.

  2. Differential Proteomic Analysis of Anthers between Cytoplasmic Male Sterile and Maintainer Lines in Capsicum annuum L.

    Directory of Open Access Journals (Sweden)

    Zhiming Wu

    2013-11-01

    Full Text Available Cytoplasmic male sterility (CMS, widely used in the production of hybrid seeds, is a maternally inherited trait resulting in a failure to produce functional pollen. In order to identify some specific proteins associated with CMS in pepper, two-dimensional gel electrophoresis (2-DE was applied to proteomic analysis of anthers/buds between a CMS line (designated NA3 and its maintainer (designated NB3 in Capsicum annuum L. Thirty-three spots showed more than 1.5-fold in either CMS or its maintainer. Based on mass spectrometry, 27 spots representing 23 distinct proteins in these 33 spots were identified. Proteins down-regulated in CMS anthers/buds includes ATP synthase D chain, formate dehydrogenase, alpha-mannosidas, RuBisCO large subunit-binding protein subunit beta, chloroplast manganese stabilizing protein-II, glutathione S-transferase, adenosine kinase isoform 1T-like protein, putative DNA repair protein RAD23-4, putative caffeoyl-CoA 3-O-methyltransferase, glutamine synthetase (GS, annexin Cap32, glutelin, allene oxide cyclase, etc. In CMS anthers/buds, polyphenol oxidase, ATP synthase subunit beta, and actin are up-regulated. It was predicted that male sterility in NA3 might be related to energy metabolism turbulence, excessive ethylene synthesis, and suffocation of starch synthesis. The present study lays a foundation for future investigations of gene functions associated with pollen development and cytoplasmic male sterility, and explores the molecular mechanism of CMS in pepper.

  3. 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

  4. Cytological study of radiation induced alterations in cytoplasmic factors controlling male sterility in corn. Progress report, February 28, 1975--December 1, 1975

    International Nuclear Information System (INIS)

    Edwardson, J.R.

    1975-01-01

    Progress is reported on the following research projects: cytoplasmic constituents of the embryo of various gymnosperms and angiosperms; cytoplasmic male sterility in corn; modification of cytoplasmic sterility factors using gamma radiation, EMS, and ethidium bromide; selection for sterile, blight-resistant corn plants; electron microscopy study of abnormal mitochondria in cytoplasm of corn; cytoplasmic male sterility in Petunia; non-Mendelian variegation in Petunia and Nicotiana; graft transmission of cytoplasmic male sterility; cytoplasmic male sterility in Vicia faba; and studies on Blakeslee's I virus in Datura

  5. Introduction, maintenance and utilization of male sterility in leek (Allium ampeloprasum L.) = [Inductie, handhaving en gebruik van mannelijke steriliteit in prei (Allium ampeloprasum L.)

    NARCIS (Netherlands)

    Silvertand, B.

    1996-01-01


    This thesis describes research work performed in leek in relation to efforts to obtain or exploit a male sterility system for hybrid leek breeding. Male sterile plants can be found in every leek cultivar. The male sterility trait can be explained by a nuclear monogenic inheritance or by a

  6. Ontogenetically-regulated male sterility in tissue culture - induced and spontaneous sorghum mutants

    Directory of Open Access Journals (Sweden)

    Elkonin L.A.

    2003-01-01

    Full Text Available Variability of male fertility expression in the AS-1 line, a somaclonal variant obtained from tissue culture of CMS-plant, and in the progeny of revenant '124-1' obtained from fertile tiller, which developed on CMS-plant transferred from the field to the greenhouse, was investigated. Both revertants were characterized by similar expression of male fertility during plant ontogenesis: the panicle on the main tiller was almost completely sterile whereas formation of fertile pollen grains and seed set were observed on the panicles of the shoot tillers. A clear basipetal gradient of male fertility was manifested on all panicles: the base had significantly higher per cent of fertile pollen grains in comparison with the middle part, while in the top the anthers were either absent or had few sterile pollen grains. Such an ontogenetically-regulated restoration of male fertility was controlled by nuclear genes and could be transferred through the pollen in crosses with progenitor CMS-line. Growing of AS-1 plants in the growth chambers simultaneously under a long (16/8 and a short (12/12 daylength conditions demonstrated that differences of fertility level in different tillers was not caused by change of photoperiod during plant ontogenesis and functioning of photoperiod-sensitive fertility restoring gene. Whereas, the ontogenetically-regulated expression of male fertility in both revenants was temperature-dependent and was clearly manifested under relatively cool conditions during 2-week period before the beginning of anthesis of the first panicle (average daily temperature 21°C. The increase of the average daily temperature by 2-3 С resulted in sharp increase of male fertility level. Possibility of using AS-1 line in a new "two-line system" of hybrid seed production, which require only two lines (sterile mutant and fertility restorer, is discussed.

  7. Selection and characterization of a novel photoperiod-sensitive male sterile line in upland cotton.

    Science.gov (United States)

    Ma, Jianhui; Wei, Hengling; Liu, Ji; Song, Meizhen; Pang, Chaoyou; Wang, Long; Zhang, Wenxiang; Fan, Shuli; Yu, Shuxun

    2013-07-01

    Upland cotton (Gossypium hirsutum L.) shows strong heterosis. However, heterosis is not widely utilized owing to the high cost of hybrid seed production. Creation of a photoperiod-sensitive genetic male sterile line could substantially reduce the cost of hybrid seed production in upland cotton. Such a mutant with virescent marker was found by space mutation in near-earth orbit and its traits had been stable after 4 years of selection in Anyang and Sanya, China. This mutant was fertile with an 11-12.5 h photoperiod when the temperature was higher than 21.5 °C and was sterile with a 13-14.5 h photoperiod. Genetic analysis indicated that both traits were controlled by a single recessive gene or two closely linked genes. Also, the cytological observations and transcriptome profiling analysis showed that the degradation of pollen grain cytoplasm should be the primary reason why the mutant line were male sterile under long-day conditions. © 2013 Institute of Botany, Chinese Academy of Sciences.

  8. Identification of Proteins Involved in Carbohydrate Metabolism and Energy Metabolism Pathways and Their Regulation of Cytoplasmic Male Sterility in Wheat

    Directory of Open Access Journals (Sweden)

    Xingxia Geng

    2018-01-01

    Full Text Available Cytoplasmic male sterility (CMS where no functional pollen is produced has important roles in wheat breeding. The anther is a unique organ for male gametogenesis and its abnormal development can cause male sterility. However, the mechanisms and regulatory networks related to plant male sterility are poorly understood. In this study, we conducted comparative analyses using isobaric tags for relative and absolute quantification (iTRAQ of the pollen proteins in a CMS line and its wheat maintainer. Differentially abundant proteins (DAPs were analyzed based on Gene Ontology classifications, metabolic pathways and transcriptional regulation networks using Blast2GO. We identified 5570 proteins based on 23,277 peptides, which matched with 73,688 spectra, including proteins in key pathways such as glyceraldehyde-3-phosphate dehydrogenase, pyruvate kinase and 6-phosphofructokinase 1 in the glycolysis pathway, isocitrate dehydrogenase and citrate synthase in the tricarboxylic acid cycle and nicotinamide adenine dinucleotide (NADH-dehydrogenase and adenosine-triphosphate (ATP synthases in the oxidative phosphorylation pathway. These proteins may comprise a network that regulates male sterility in wheat. Quantitative real time polymerase chain reaction (qRT-PCR analysis, ATP assays and total sugar assays validated the iTRAQ results. These DAPs could be associated with abnormal pollen grain formation and male sterility. Our findings provide insights into the molecular mechanism related to male sterility in wheat.

  9. Sterility and mating competitiveness of irradiated males of the large milkweed bug, Oncopeltus fasciatus

    International Nuclear Information System (INIS)

    Moursy, L.E.; Eesa, N.M.; Cutkomp, L.K.

    1991-01-01

    Low level gamma radiation adversely affected the reproductive capacity of the large milkweed bug, oncopeltus fasciatus dallas, as expressed by fecundity and fertility. Treatment was applied to late 5th instar male nymphs. Both fecundity and fertility decreased linearly with the treatment dose and complete sterility occurred when males were exposed to 6 kilorads and mated with normal females. The mating competitiveness of O. fasciatus males irradiated at late 5th instar nymphs decreased linearly with the treatment dose. A strong negative relationship existed between dose and mating competitiveness ( r = -0.93). A 3:2 ratio of irradiated males at 4 kilorads ( as late 5th instar as many progeny as normal in F 1 .2 tab.,1 fig

  10. 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.

  11. Cytoplasmic effects on DNA methylation between male sterile lines and the maintainer in wheat (Triticum aestivum L.).

    Science.gov (United States)

    Ba, Qingsong; Zhang, Gaisheng; Niu, Na; Ma, Shoucai; Wang, Junwei

    2014-10-01

    Male sterile cytoplasm plays an important role in hybrid wheat, and three-line system including male sterile (A line), its maintainer (B line) and restoring (R line) has played a major role in wheat hybrid production. It is well known that DNA methylation plays an important role in gene expression regulation during biological development in wheat. However, no reports are available on DNA methylation affected by different male sterile cytoplasms in hybrid wheat. We employed a methylation-sensitive amplified polymorphism technique to characterize nuclear DNA methylation in three male sterile cytoplasms. A and B lines share the same nucleus, but have different cytoplasms which is male sterile for the A and fertile for the B. The results revealed a relationship of DNA methylation at these sites specifically with male sterile cytoplasms, as well as male sterility, since the only difference between the A lines and B line was the cytoplasm. The DNA methylation was markedly affected by male sterile cytoplasms. K-type cytoplasm affected the methylation to a much greater degree than T-type and S-type cytoplasms, as indicated by the ratio of methylated sites, ratio of fully methylated sites, and polymorphism between A lines and B line for these cytoplasms. The genetic distance between the cytoplasm and nucleus for the K-type is much greater than for the T- and S-types because the former is between Aegilops genus and Triticum genus and the latter is within Triticum genus between Triticum spelta and Triticum timopheevii species. Thus, this difference in genetic distance may be responsible for the variation in methylation that we observed. Copyright © 2014. Published by Elsevier B.V.

  12. Semiochemical mediated enhancement of males to complement sterile insect technique in management of the tephritid pest Bactrocera tryoni (Froggatt)

    OpenAIRE

    Khan, Mohammed Abul Monjur; Manoukis, Nicholas C.; Osborne, Terry; Barchia, Idris M.; Gurr, Geoff M.; Reynolds, Olivia L.

    2017-01-01

    Queensland fruit fly, Bactrocera tryoni (Froggatt), is the most significant pest of Australia’s $9 billion horticulture industry. The sterile insect technique (SIT) and cue-lure (a synthetic analogue of raspberry ketone (RK))-based male annihilation technique (MAT) are two of the most effective management tools against this pest. However, combining these two approaches is considered incompatible as MAT kills sterile and ‘wild’ males indiscriminately. In the present study we tested the effect ...

  13. Quality of Sterile Male Tsetse after Long Distance Transport as Chilled, Irradiated Pupae.

    Directory of Open Access Journals (Sweden)

    Momar Talla Seck

    2015-11-01

    Full Text Available Tsetse flies transmit trypanosomes that cause human and African animal trypanosomosis, a debilitating disease of humans (sleeping sickness and livestock (nagana. An area-wide integrated pest management campaign against Glossina palpalis gambiensis has been implemented in Senegal since 2010 that includes a sterile insect technique (SIT component. The SIT can only be successful when the sterile males that are destined for release have a flight ability, survival and competitiveness that are as close as possible to that of their wild male counterparts.Tests were developed to assess the quality of G. p. gambiensis males that emerged from pupae that were produced and irradiated in Burkina Faso and Slovakia (irradiation done in Seibersdorf, Austria and transported weekly under chilled conditions to Dakar, Senegal. For each consignment a sample of 50 pupae was used for a quality control test (QC group. To assess flight ability, the pupae were put in a cylinder filtering emerged flies that were able to escape the cylinder. The survival of these flyers was thereafter monitored under stress conditions (without feeding. Remaining pupae were emerged and released in the target area of the eradication programme (RF group. The following parameter values were obtained for the QC flies: average emergence rate more than 69%, median survival of 6 days, and average flight ability of more than 35%. The quality protocol was a good proxy of fly quality, explaining a large part of the variances of the examined parameters.The quality protocol described here will allow the accurate monitoring of the quality of shipped sterile male tsetse used in operational eradication programmes in the framework of the Pan-African Tsetse and Trypanosomosis Eradication Campaign.

  14. High-resolution fine mapping of ps-2, a mutated gene conferring functional male sterility in tomato due to non-dehiscent anthers

    NARCIS (Netherlands)

    Gorguet, B.J.M.; Schipper, E.H.; Heusden, van A.W.; Lindhout, P.

    2006-01-01

    Functional male sterility is an important trait for the production of hybrid seeds. Among the genes coding for functional male sterility in tomato is the positional sterility gene ps-2. ps-2 is monogenic recessive, confers non-dehiscent anthers and is the most suitable for practical uses. In order

  15. Use of sterile male technique for insects to eradicate red palm weevil

    International Nuclear Information System (INIS)

    Al-Turaihi, E.H.

    2012-01-01

    The date palm plantations in the Middle East countries are infested by a devastating insect which is called red palm weevil originally from India and spread firstly into the Arab Gulf countries through imported palm trees. Red palm weevil is mainly controlled by using synthetic chemical pesticides and aggregative pheromone traps. Use of chemical pesticides has dramatically increased during recent years and posed many poisoning cases, pollution of environment, killed beneficial and non-target insects. The aim of this study is to highlight the application of Sterile Insect Technique to suppress or eradicate red palm weevil. The results revealed that the application of Sterile Insect Technique to control cotton boll weevil (Anthonomus grandis) in USA could be considered as an ideal example to apply the Sterile Insect Technique against red palm weevil because both species have similarities such as : both are exotic pests; have protected larval and pupal stages; have limited hosts; have economic importance; have an aggregative pheromone that attracts males and females; that can be used for detection and survey; and finally both insects are Coleopterans belonging to the same family.

  16. Development of Novel Cytoplasmic Male Sterile Source from Dongxiang Wild Rice (Oryza rufipogon

    Directory of Open Access Journals (Sweden)

    Xian-hua SHEN

    2013-09-01

    Full Text Available This study was conducted to develop and characterize a novel cytoplasmic male sterile (CMS source which was identified from Dongxiang wild rice (Oryza rufipogon by crossing Dongxiang wild rice as female with Zhongzao 35, an indica inbred variety, as male and continuous backcrossing with Zhongzao 35. Observation under optical microscope manifested that this novel CMS belonged to typical abortion type with less pollen compared with wild abortive type cytoplasm (CMS-WA. Sequential planting showed that this novel CMS has complete and stable male sterility. Testcross experiment showed that all the 24 tested materials including maintainer and restorer lines of CMS-WA and Honglian type cytoplasm (CMS-HL and other indica inbred varieties are the maintainers with complete maintaining ability, suggesting that this novel CMS has fertility restoration totally different from CMS-WA and CMS-HL and belongs to a novel type of CMS. So far, we only discovered a unique fertility restoration source for this novel CMS. Inheritance analysis showed that the fertility restoration of this CMS was governed by three pairs of independent dominant genes. Prospect for application of this novel CMS system in hybrid rice breeding was also discussed.

  17. Research on cotton anther development of three male-sterile lines

    International Nuclear Information System (INIS)

    Dou Liping; Tang Canming; Yue Jieyu; Wang Qingya

    2009-01-01

    Pollens of Sumian 22 were irradiated by 60 Co γ-rays at a dose of 20Gy, then fertilized to pistil and harvested seed. Three male-sterile lines were selected from M 1 plants, their anther observed by paraffin slice technique. Although there were some different characteristics during the abortion anther development, the abortion was consistent: the abortion stage from the development periods of pollen mother cells to microspore, pollen mother cells, tapetum, middle layer cells and the shape of anther were affected, the results contained micronucleus and double nucleus, cytoplasm expansion during the period of meiosis, tapetum and middle layer cells and so on were abnormal. (authors)

  18. 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.

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

    Science.gov (United States)

    de Souza, João Maria Gomes Alencar; Molina, Wagner Franco; de Almeida, Lúcia Maria; de Gouveia, Milson Bezerra; de Macêdo, Francisco Pepino; Laumann, Raul Alberto; Paranhos, Beatriz Aguiar Jordão

    2015-01-01

    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. PMID:26075293

  20. A study on the spreading ability of radiation-sterilized male moth of bombyx mandarin in field

    International Nuclear Information System (INIS)

    Yang Rongxin; Xia Darong; Gu Weiping; Zhang Yanjun

    1998-01-01

    The mulberry wild silkworm (MWS), belong to the Bombycidae of Lepidoptera, is serious pest of sericulture. The female moth of MWS is sterile and the male moth is sub-sterile when they were treated with 250 Gy 60 Co γ-ray (dose rate: 1.05 Gy/min), and their filial generations was sterile. The spreading ability of male moth of MWS in field and retrieving the marked MWS male moth with the trapping method was studied. The trapping solution was composed of sugar, vinegar, wine and alive female moth. The retrieving rate of MWS male moth amounted to 12.6%∼13.5% of released moth in field. The spreading range in 24 hours for sterile MWS male moth reached to 700 m, and 90.8% of MWS male moth was in an area of 5 m radius from the releasing centre. It is concluded that thirty releasing centres per hectare are needed to make the irradiated sterilized insects spread for controlling the MWS in field

  1. Genetic studies on cytoplasmic male sterility in maize. Progress report, April 15, 1990--April 14, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Laughnan, J.R.

    1992-05-01

    Our research concerns the basic mechanisms of cytoplasmic male sterility (CMS) and fertility restoration in maize. The molecular determination of CMS is in the DNA of the mitochondria (mtDNA) but specific nuclear restorer-of-fertility (Rf) genes can overrule the male-sterile effect of the cytoplasm. Our approach to the study of the Rf genes is threefold. We are attempting to tag the cms-S Rf genes and the cms-T Rf2 gene with controlling elements (CEs). Since we have identified a number of spontaneous Rf genes for cms-S and have demonstrated that they are themselves transposable, we are also searching for cases in which an Rf gene is inserted into a wild-type gene. The other aspect of our research involves the nuclear control over the organization of the mitochondrial genome. We found that the changes in mtDNA organization upon cytoplasmic reversion to fertility were characteristic of the nuclear background in which the reversion event occurred. We have investigated whether these differences are a reflection of differences in the organization of the mtDNA genome before reversion.

  2. Laparoscopic-assisted colopexy and sterilization in male dogs: short-term results and physiologic consequences.

    Science.gov (United States)

    Mathon, Didier H; Palierne, Sophie; Meynaud-Collard, Patricia; Layssol-Lamour, Catherine; Dulaurent-Ferrieres, Alice; Colson, Arnaud; Lacroix, Marlene; Bousquet-Melou, Alain; Delverdier, Maxence; Autefage, Andre

    2011-06-01

    To describe laparoscopic-assisted colopexy and sterilization, and evaluate outcome and effects in healthy male dogs. Experimental study. Male Beagle dogs (n=7). A laparoscopic-assisted, extracorporeally sutured colopexy, and sterilization by ligation and section of the testicular vessels and ductus deferens were evaluated 11 weeks after surgery. Ex vivo tensile tests were performed on the colopexy sites and loss of testicular function was assessed by monitoring serum testosterone, and by ultrasonographic and histologic examinations of the testes. Systemic inflammation and potential iatrogenic colonic functional disorders were investigated by monitoring serum C-reactive protein (CRP) in the perioperative period and from a sulfapyridine (SP) kinetic profile obtained before and 10 weeks after surgery. No intraoperative complications were recorded and clinical outcome was considered fair in all dogs. A mean tensile force of 42 N was required to disrupt colopexies. No relevant postoperative increase in CRP concentrations or changes in SP kinetics were observed. Testicular function was lost. Laparoscopic-assisted colopexy achieved adhesion of the colon to the abdominal wall and testicular endocrine function and spermatogenesis were eliminated by laparoscopic castration. © Copyright 2011 by The American College of Veterinary Surgeons.

  3. Wild Nicotiana Species as a Source of Cytoplasmic Male Sterility in Nicotianatabacum

    Directory of Open Access Journals (Sweden)

    Nikova V

    2014-12-01

    Full Text Available The results of our experiments executed to obtain tobacco male sterile lines through interspecific hybridization are summarized. Ten wild species from the genus Nicotiana: N. excelsior (exc, N. amplexicaulis (amp, N. rustica (rus, Nicotianaglauca (gla, N. velutina (vel, N. benthamiana (ben, N. maritima (mar, N. paniculata (pan, N. longiflora (lon and N. africana (afr were used as cytoplasmic donors and N. tabacum, cv. HarmanliiskaBasma (HB as a donor of the nucleus. Genetic effects of cytoplasmic-nuclear interaction of the studied species are discussed. Our results suggested that cytoplasmic male sterility (CMS was expressed when the cytoplasms of the above mentioned wild Nicotiana species were combined with the nucleus of N. tabacum. The 10 sources of CMS obtained in tobacco were characterized by altered flower phenotypes. Flowers are classified into types according the stamen, pistil and corolla modification. All these CMS sources were backcrossed to Oriental tobaccos, cvs. Tekne, Nevrokop B-12, Kroumovgrad 90 and Djebel 576, to develop corresponding CMS lines. The investigated cytoplasms produced compete male sterility in all those cultivars. The CMS lines preserved flower types, specific for every “sterile” cytoplasm. The extent of male organ modifications varied from apparently normal (but pollenless stamens in CMS (pan, (afr, some plants of (vel (mar through different degrees of malformations (shriveled anther on shortened filaments (lon, pinnate-like anthers on filaments of normal length (amp, petal - (ben, pistil- or stigma-like structures (rus, (gla to lack of male reproductive organs in (exc and in some plants of (vel, (mar, (rus and (gla. Most of the above mentioned cytoplasms had normal female gametophyte and good seed productivity. Alterations of the pistils were observed in CMS (rus, (exc and (ben causing reduction of the seed set. Electrophoresis of seed proteins of the tobacco cultivars and their CMS lines also suggested that

  4. Influence of ionizing radiation on flight activity of F-1 progeny of sub-sterilized male moths of Spodoptera litura (fabr.) (lepidoptera: noctuidae)

    International Nuclear Information System (INIS)

    Zubeda; Zarin, Mahtab; Seth, R.K.; Seth, Ranjana

    2012-01-01

    Radiation mediated 'Inherited or F-1 sterility', as a parabiological (genetic) control measure using a range of 100-130 Gy to the male parents, has been proposed for the suppression of Spodoptera litura (Seth and Sehgal 1993; Seth and Sharma 2001). This is a modified Sterile Insect Technique (SIT) wherein sub-sterilizing gamma doses are preferred than the high (100%) sterilizing dose in order to sustain the insects competitiveness. In the present study the flight activity of F-1 progeny of sub-sterilized male moths was ascertained to judge the performance of F-1 sterility as a control tactic. The male flight ability of F-1 progeny males derived from sub-sterilized male moths, S. litura in presence of normal females, was tested in two modes in 'Flight assay chamber' (a perspex cage of size, 45 x 45 x 60 cm) having a black hollow cylinder (25.4 cm dia, 30.5 cm ht.) placed inside

  5. Functional Marker Assisted Improvement of Stable Cytoplasmic Male Sterile Lines of Rice for Bacterial Blight Resistance.

    Science.gov (United States)

    Ramalingam, Jegadeesan; Savitha, Palanisamy; Alagarasan, Ganesh; Saraswathi, Ramasamy; Chandrababu, Ranganathan

    2017-01-01

    Bacterial blight (BB), caused by Xanthomonas oryzae pv .oryzae is one among the major diseases in rice, which in severe condition cause losses up to 60% in total yield. Marker assisted pyramiding of three broad spectrum BB resistance genes ( xa5, xa13 , and Xa21 ) in prominent rice varieties is the most economical and effective strategy for the management of the BB disease. We report here the pyramiding of three genes ( xa5, xa13 , and Xa21 ) in maintainer lines (CO 2B, CO 23B, and CO 24B) of three promising wild abortive cytoplasmic male sterile lines (CO 2A, CO 23A, and CO 24A) through functional markers assisted back cross breeding. IRBB60 with xa5, xa13 , and Xa21 genes is used as a donor parent. BC 2 F 1 and BC 2 F 2 generations from a cross of CO 2B, CO 23B, and CO 24B with IRBB60 were evaluated for bacterial blight and non-fertility restoration. In BC 2 F 1 , plants with all three resistance genes ( xa5, xa13 , and Xa21 ) and high parent genome recovery was identified. In BC 2 F 2 , plants with all resistance genes and without fertility restorer ( Rf3 and Rf4 ) were selected. Based on agronomic traits, BB resistance and maintenance of sterility, two plants each in CO 2B × IRBB60, CO 24B × IRBB60 and one plant in CO 23B × IRBB60 combinations were identified. The identified lines were crossed with respective male sterile lines for conversion of improved B line into CMS line through back-crossing, in addition to selfing. The plants with high recurrent genome and phenotypically similar to parental lines and sterile are being used for the hybrid rice development program. Currently, using these lines (improved CMS line), test crosses were made to develop new rice hybrids. Hybrids combinations viz. , CO 23A × AD08009R and CO 24A × IET20898R were found to be stable at different locations with high yield. The R line used in this study has been introgressed with xa5, xa13 , and Xa21 genes in a separate breeding program. These new hybrids with resistance against

  6. Functional Marker Assisted Improvement of Stable Cytoplasmic Male Sterile Lines of Rice for Bacterial Blight Resistance

    Directory of Open Access Journals (Sweden)

    Jegadeesan Ramalingam

    2017-06-01

    Full Text Available Bacterial blight (BB, caused by Xanthomonas oryzae pv.oryzae is one among the major diseases in rice, which in severe condition cause losses up to 60% in total yield. Marker assisted pyramiding of three broad spectrum BB resistance genes (xa5, xa13, and Xa21 in prominent rice varieties is the most economical and effective strategy for the management of the BB disease. We report here the pyramiding of three genes (xa5, xa13, and Xa21 in maintainer lines (CO 2B, CO 23B, and CO 24B of three promising wild abortive cytoplasmic male sterile lines (CO 2A, CO 23A, and CO 24A through functional markers assisted back cross breeding. IRBB60 with xa5, xa13, and Xa21 genes is used as a donor parent. BC2F1 and BC2F2 generations from a cross of CO 2B, CO 23B, and CO 24B with IRBB60 were evaluated for bacterial blight and non-fertility restoration. In BC2F1, plants with all three resistance genes (xa5, xa13, and Xa21 and high parent genome recovery was identified. In BC2F2, plants with all resistance genes and without fertility restorer (Rf3 and Rf4 were selected. Based on agronomic traits, BB resistance and maintenance of sterility, two plants each in CO 2B × IRBB60, CO 24B × IRBB60 and one plant in CO 23B × IRBB60 combinations were identified. The identified lines were crossed with respective male sterile lines for conversion of improved B line into CMS line through back-crossing, in addition to selfing. The plants with high recurrent genome and phenotypically similar to parental lines and sterile are being used for the hybrid rice development program. Currently, using these lines (improved CMS line, test crosses were made to develop new rice hybrids. Hybrids combinations viz., CO 23A × AD08009R and CO 24A × IET20898R were found to be stable at different locations with high yield. The R line used in this study has been introgressed with xa5, xa13, and Xa21 genes in a separate breeding program. These new hybrids with resistance against bacterial blight

  7. Functional Marker Assisted Improvement of Stable Cytoplasmic Male Sterile Lines of Rice for Bacterial Blight Resistance

    Science.gov (United States)

    Ramalingam, Jegadeesan; Savitha, Palanisamy; Alagarasan, Ganesh; Saraswathi, Ramasamy; Chandrababu, Ranganathan

    2017-01-01

    Bacterial blight (BB), caused by Xanthomonas oryzae pv.oryzae is one among the major diseases in rice, which in severe condition cause losses up to 60% in total yield. Marker assisted pyramiding of three broad spectrum BB resistance genes (xa5, xa13, and Xa21) in prominent rice varieties is the most economical and effective strategy for the management of the BB disease. We report here the pyramiding of three genes (xa5, xa13, and Xa21) in maintainer lines (CO 2B, CO 23B, and CO 24B) of three promising wild abortive cytoplasmic male sterile lines (CO 2A, CO 23A, and CO 24A) through functional markers assisted back cross breeding. IRBB60 with xa5, xa13, and Xa21 genes is used as a donor parent. BC2F1 and BC2F2 generations from a cross of CO 2B, CO 23B, and CO 24B with IRBB60 were evaluated for bacterial blight and non-fertility restoration. In BC2F1, plants with all three resistance genes (xa5, xa13, and Xa21) and high parent genome recovery was identified. In BC2F2, plants with all resistance genes and without fertility restorer (Rf3 and Rf4) were selected. Based on agronomic traits, BB resistance and maintenance of sterility, two plants each in CO 2B × IRBB60, CO 24B × IRBB60 and one plant in CO 23B × IRBB60 combinations were identified. The identified lines were crossed with respective male sterile lines for conversion of improved B line into CMS line through back-crossing, in addition to selfing. The plants with high recurrent genome and phenotypically similar to parental lines and sterile are being used for the hybrid rice development program. Currently, using these lines (improved CMS line), test crosses were made to develop new rice hybrids. Hybrids combinations viz., CO 23A × AD08009R and CO 24A × IET20898R were found to be stable at different locations with high yield. The R line used in this study has been introgressed with xa5, xa13, and Xa21 genes in a separate breeding program. These new hybrids with resistance against bacterial blight will increase

  8. Short range attraction of Ceratitis capitata (Diptera: Tephritidae) sterile males to six commercially available plant essential oils

    Science.gov (United States)

    Plant essential oils have a number of roles in insect pest management. For male Ceratitis capitata, this includes use of angelica seed oil as long range attractants and ginger root oil as aromatherapy, which is exposure to sterile males to increase mating success. Neither of these plants are hosts f...

  9. On the sterile male release technique: sterilization by γ-radiation (60Co) in Amblyomma variegatum (Fabricius, 1794), Hyalomma anatolicum excavatum (Koch, 1844), and Rhipicephalus appendiculatus (Neumann, 1901)

    International Nuclear Information System (INIS)

    Beuthner, U.

    1975-01-01

    Nymphal stages (2-3 days before moulting) and adult male ticks (one week after moulting) of Amblyomma variegatum, Hyalomma a. excavatum, and Rhipicephalus appendiculatus were exposed to irradiation with gamma-rays in the range of 0-8 krad. All ticks irradiated with a dose of 2 krad or more became 100% sterile. There was found no significant difference in engorged weight, time of engorgement, and egg weight in control-ticks and female partner-ticks of Amblyomma variegatum, males of which had received an irradiation dose of 2 krad as nymphs or adults. The same result was obtained in Hyalomma a. excavatum and Rhipicephalus appendiculatus when the males were irradiated as adults with 2 krad. However, significant differences occured when males of Hyalomma a. excavatum and Rhipicephalus appendiculatus were irradiated as nymphs with 2 krad. This applied also when males of all 3 species of ticks (nymphs or adults) were irradiated with higher doses. Since it was found that parthenogenesis occured in different degrees in all 3 species of ticks the practical application of the sterile-male-release-technique appears doubtful at least in the 3 investigated strains. (orig.) [de

  10. Mapping of a rice thermosensitive genic male sterility gene from a TGMS mutant line

    Energy Technology Data Exchange (ETDEWEB)

    Vu Duc Quang; Nguyen Van Dong; Pham Ngoc Luong; Tran Duy Quy [Argicultural Genetics Institute, Hanoi (Viet Nam); Nguyen, Henry T. [Texas Tech Univ., Department of Plant and Soil Science, Lubbock TX (United States)

    2001-03-01

    At the Agricultural Genetics Institute (AGI), Hanoi, Vietnam, a number of thermo-sensitive genic male sterility (TGMS) homozygous rice lines have been developed by means of experimental mutagenesis followed by anther culture techniques. One of them (TGMS-1 indica mutant line) was used in this research. The critical temperature (at the period from pollen mother cell formation to the beginning of meiotic division) for TGMS-1 sterility was 24-25degC, below which the plants were fertile and above which the plants became sterile. Segregation analysis showed that the TGMS trait of the TGMS-1 mutant line was controlled by a single recessive gene. An F{sub 2} mapping population from a cross between TGMS-1 mutant line and CH1 (a fertile indica line) was developed for tagging and mapping the TGMS gene. From survey of 200 AFLP primer combinations in a bulked segregant analysis, 4 AFLP markers (E2/M5-200, E3/M16-400, E5/M12-600 and E5/M12-200) linked to TGMS-1 gene were identified and cloned. All except E2/M5-200 were found to be low-copy number sequences. The marker E5/M12-600 showed polymorphism in RFLP analysis and was closely linked to the TGMS gene at a distance of 3.3cM. This marker was subsequently mapped on chromosome 2 using doubled-haploid mapping populations derived from the crosses IR64xAzucena and CT9993xIR62666. Linkage of microsatellite marker RM27 with the TGMS gene further confirmed its location on chromosome 2. The closest marker, E5/M12-600, was sequenced so that a PCR marker can be developed for the use in marker-assisted breeding. The application of TGMS genes to the commercial two-line hybrid rice breeding system was discussed. (author)

  11. Mapping of a rice thermosensitive genic male sterility gene from a TGMS mutant line

    International Nuclear Information System (INIS)

    Vu Duc Quang; Nguyen Van Dong; Pham Ngoc Luong; Tran Duy Quy; Nguyen, Henry T.

    2001-01-01

    At the Agricultural Genetics Institute (AGI), Hanoi, Vietnam, a number of thermo-sensitive genic male sterility (TGMS) homozygous rice lines have been developed by means of experimental mutagenesis followed by anther culture techniques. One of them (TGMS-1 indica mutant line) was used in this research. The critical temperature (at the period from pollen mother cell formation to the beginning of meiotic division) for TGMS-1 sterility was 24-25degC, below which the plants were fertile and above which the plants became sterile. Segregation analysis showed that the TGMS trait of the TGMS-1 mutant line was controlled by a single recessive gene. An F 2 mapping population from a cross between TGMS-1 mutant line and CH1 (a fertile indica line) was developed for tagging and mapping the TGMS gene. From survey of 200 AFLP primer combinations in a bulked segregant analysis, 4 AFLP markers (E2/M5-200, E3/M16-400, E5/M12-600 and E5/M12-200) linked to TGMS-1 gene were identified and cloned. All except E2/M5-200 were found to be low-copy number sequences. The marker E5/M12-600 showed polymorphism in RFLP analysis and was closely linked to the TGMS gene at a distance of 3.3cM. This marker was subsequently mapped on chromosome 2 using doubled-haploid mapping populations derived from the crosses IR64xAzucena and CT9993xIR62666. Linkage of microsatellite marker RM27 with the TGMS gene further confirmed its location on chromosome 2. The closest marker, E5/M12-600, was sequenced so that a PCR marker can be developed for the use in marker-assisted breeding. The application of TGMS genes to the commercial two-line hybrid rice breeding system was discussed. (author)

  12. 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

  13. 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

  14. De Novo Assembly and Transcriptome Analysis of Wheat with Male Sterility Induced by the Chemical Hybridizing Agent SQ-1.

    Directory of Open Access Journals (Sweden)

    Qidi Zhu

    Full Text Available Wheat (Triticum aestivum L., one of the world's most important food crops, is a strictly autogamous (self-pollinating species with exclusively perfect flowers. Male sterility induced by chemical hybridizing agents has increasingly attracted attention as a tool for hybrid seed production in wheat; however, the molecular mechanisms of male sterility induced by the agent SQ-1 remain poorly understood due to limited whole transcriptome data. Therefore, a comparative analysis of wheat anther transcriptomes for male fertile wheat and SQ-1-induced male sterile wheat was carried out using next-generation sequencing technology. In all, 42,634,123 sequence reads were generated and were assembled into 82,356 high-quality unigenes with an average length of 724 bp. Of these, 1,088 unigenes were significantly differentially expressed in the fertile and sterile wheat anthers, including 643 up-regulated unigenes and 445 down-regulated unigenes. The differentially expressed unigenes with functional annotations were mapped onto 60 pathways using the Kyoto Encyclopedia of Genes and Genomes database. They were mainly involved in coding for the components of ribosomes, photosynthesis, respiration, purine and pyrimidine metabolism, amino acid metabolism, glutathione metabolism, RNA transport and signal transduction, reactive oxygen species metabolism, mRNA surveillance pathways, protein processing in the endoplasmic reticulum, protein export, and ubiquitin-mediated proteolysis. This study is the first to provide a systematic overview comparing wheat anther transcriptomes of male fertile wheat with those of SQ-1-induced male sterile wheat and is a valuable source of data for future research in SQ-1-induced wheat male sterility.

  15. De Novo Assembly and Transcriptome Analysis of Wheat with Male Sterility Induced by the Chemical Hybridizing Agent SQ-1

    Science.gov (United States)

    Zhang, Gaisheng; Ju, Lan; Zhang, Jiao; Yu, Yongang; Niu, Na; Wang, Junwei; Ma, Shoucai

    2015-01-01

    Wheat (Triticum aestivum L.), one of the world’s most important food crops, is a strictly autogamous (self-pollinating) species with exclusively perfect flowers. Male sterility induced by chemical hybridizing agents has increasingly attracted attention as a tool for hybrid seed production in wheat; however, the molecular mechanisms of male sterility induced by the agent SQ-1 remain poorly understood due to limited whole transcriptome data. Therefore, a comparative analysis of wheat anther transcriptomes for male fertile wheat and SQ-1–induced male sterile wheat was carried out using next-generation sequencing technology. In all, 42,634,123 sequence reads were generated and were assembled into 82,356 high-quality unigenes with an average length of 724 bp. Of these, 1,088 unigenes were significantly differentially expressed in the fertile and sterile wheat anthers, including 643 up-regulated unigenes and 445 down-regulated unigenes. The differentially expressed unigenes with functional annotations were mapped onto 60 pathways using the Kyoto Encyclopedia of Genes and Genomes database. They were mainly involved in coding for the components of ribosomes, photosynthesis, respiration, purine and pyrimidine metabolism, amino acid metabolism, glutathione metabolism, RNA transport and signal transduction, reactive oxygen species metabolism, mRNA surveillance pathways, protein processing in the endoplasmic reticulum, protein export, and ubiquitin-mediated proteolysis. This study is the first to provide a systematic overview comparing wheat anther transcriptomes of male fertile wheat with those of SQ-1–induced male sterile wheat and is a valuable source of data for future research in SQ-1–induced wheat male sterility. PMID:25898130

  16. Photosynthetic characteristics of leaves of male-sterile and hermaphrodite sex types of Plantago lanceolata grown under conditions of contrasting nitrogen and light availabilities

    NARCIS (Netherlands)

    Poot, P.; Pilon, J.; Pens, T.L.

    1996-01-01

    Plantago lanceolata is it gynodioecious species: In natural populations male steriles (MS) coexist with hermaphrodites (H). Since male steriles have a reproductive disadvantage, without any compensation for their loss in male function by an increase in female function, they are expected to disappear

  17. Assessment of knowledge and perception regarding male sterilization (Non-Scalpel Vasectomy) among community health workers in Jharkhand, India

    OpenAIRE

    Swati Mahapatra; Chahat Narula; Chander Pal Thakur; Tapan Jyoti Kalita; Rakesh Mehra

    2014-01-01

    Introduction: In India, community health workers are the main source of information for family planning services and male population want to interact and discuss with them to clear their doubts about male oriented family planning methods. Objective: The objective of the study was to assess the knowledge and perception of community health workers regarding the modern male sterilization method. Methodology: This was a cross-sectional study conducted in Simdega district of Jharkhand. The target ...

  18. Precocious sexual signalling and mating in Anastrepha fraterculus (Diptera: Tephritidae) sterile males achieved through juvenile hormone treatment and protein supplements.

    Science.gov (United States)

    Liendo, M C; Devescovi, F; Bachmann, G E; Utgés, M E; Abraham, S; Vera, M T; Lanzavecchia, S B; Bouvet, J P; Gómez-Cendra, P; Hendrichs, J; Teal, P E A; Cladera, J L; Segura, D F

    2013-02-01

    Sexual maturation of Anastrepha fraterculus is a long process. Methoprene (a mimic of juvenile hormone) considerably reduces the time for sexual maturation in males. However, in other Anastrepha species, this effect depends on protein intake at the adult stage. Here, we evaluated the mating competitiveness of sterile laboratory males and females that were treated with methoprene (either the pupal or adult stage) and were kept under different regimes of adult food, which varied in the protein source and the sugar:protein ratio. Experiments were carried out under semi-natural conditions, where laboratory flies competed over copulations with sexually mature wild flies. Sterile, methoprene-treated males that reached sexual maturity earlier (six days old), displayed the same lekking behaviour, attractiveness to females and mating competitiveness as mature wild males. This effect depended on protein intake. Diets containing sugar and hydrolyzed yeast allowed sterile males to compete with wild males (even at a low concentration of protein), while brewer´s yeast failed to do so even at a higher concentration. Sugar only fed males were unable to achieve significant numbers of copulations. Methoprene did not increase the readiness to mate of six-day-old sterile females. Long pre-copulatory periods create an additional cost to the management of fruit fly pests through the sterile insect technique (SIT). Our findings suggest that methoprene treatment will increase SIT effectiveness against A. fraterculus when coupled with a diet fortified with protein. Additionally, methoprene acts as a physiological sexing method, allowing the release of mature males and immature females and hence increasing SIT efficiency.

  19. 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

  20. Effects of surgical and chemical sterilization on the behavior of free-roaming male dogs in Puerto Natales, Chile.

    Science.gov (United States)

    Garde, E; Pérez, G E; Vanderstichel, R; Dalla Villa, P F; Serpell, J A

    2016-01-01

    Population management of free-roaming domestic dogs (Canis lupus familiaris) is of interest due to the threat these animals pose to people, other animals and the environment. Current sterilization procedures for male dogs include surgical and chemical methods. However, little is known about how these procedures affect their behavior. The primary objective of this study was to investigate changes in selected behaviors following chemical and surgical sterilization in a male free-roaming dog (FRD) population in southern Chile. We also examined the association between serum testosterone levels and behaviors thought to be influenced by circulating androgens. A total of 174 dogs were randomly assigned to either a surgical or chemical sterilization group, or a control group. At the onset of the intervention period, 119 dogs remained and 102 dogs successfully completed the study. Each dog was monitored pre- and post-intervention using video recordings, GPS collars, and blood samples for the measurement of testosterone. Analysis of behavior revealed that surgically castrated dogs showed no reduction of sexual activity or aggression when compared to their pre-intervention behavior. Chemically sterilized dogs showed a statistically significant increase in dog-directed aggression, but no change in sexual activity. There was no change in home range size in any groups between the pre- and post-intervention measurement. We found no consistent association between levels of serum testosterone concentration and behavioral changes in any of the groups. This study presents the first detailed behavioral observations following surgical and chemical sterilization in male FRDs. The information generated is highly relevant to communities struggling with the control of FRDs. Complementary studies to further our understanding of the effects of male sterilization on the behavioral and reproductive dynamics of FRD populations are needed. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Desbalance redox en la infertilidad masculina Lack of Redox balance in male sterility

    Directory of Open Access Journals (Sweden)

    Akel Mallok

    2011-06-01

    Full Text Available La infertilidad masculina es considerada como uno de los factores que más contribuyen a la infertilidad de la pareja. En conjunción a los factores convencionales que la originan se ha identificado una causa de extraordinaria repercusión: el estrés oxidativo, el cual es el resultado del desequilibrio entre la generación de especies reactivas del oxígeno y los antioxidantes, que puede originar daños o deformidades a los espermatozoides y eventualmente infertilidad masculina. Las especies reactivas del oxígeno se producen por diversos mecanismos en el semen, por espermatozoides inmóviles o con problemas de movilidad, leucocitos y por espermatozoides normales morfológicamente pero funcionalmente anormales. Entre estos daños, se registran la peroxidación lipídica a la membrana espermática y la fragmentación del ADN tanto nuclear como mitocondrial. Los daños que causa el estrés oxidativo sobre el ADN pueden originar trastornos en la descendencia que incluyen cáncer y acondroplastia. La peroxidación lipídica, origina la alteración de la membrana que afecta su estructura y función. La membrana del espermatozoide humano contiene una elevada proporción de ácidos grasos poliinsaturados, por lo tanto su susceptibilidad a la peroxidación lipídica es muy elevada. Las especies reactivas del oxígeno tienen diversos efectos sobre las células espermáticas, constituyendo un tema muy controvertido, por lo que este artículo tuvo como propósito actualizar al lector sobre algunos de los aspectos bioquímicos relacionados con la producción de especies reactivas del oxígeno y los métodos de diagnóstico que se emplean para detectarlo en la infertilidad humana.The male sterility is considered as one of the factors more contributing to couple sterility. Join to conventional factors originate it condition it was possible to identify a cause with a high level of repercussion: the oxidative stress, which is the result of the imbalance

  2. Cytological observations on microspore degeneration in cytoplasmic male sterility induced by gamma-irradiation in sugar beets

    International Nuclear Information System (INIS)

    Mikami, Tetsuo; Kinoshita, Toshiro; Takahashi, Man-emon

    1978-01-01

    Meiotic behaviours and the abnormalities of microsporogenesis were investigated in the complete sterile plants from four kinds of γ-line, which are the progenies of the male sterile mutants induced by γ-irradiations from H-2002, and these sterile plants were compared with those of H-19 MS with S cytoplasms in spontaneous origin. In the meiosis, there was no chromosomal abnormality showing the association of nine bivalents and the regular distribution of chromosomes irrespective of the source of cytoplasms. After the liberation of quartets, the conspicuous deformity of tapetal cells occurred in the complete sterile plants throughout all kinds of γ-line and H-19 MS. The modified type of anther tapeta was newly found in several plants from γ-114. The tapetal cells surrounding anther cavity enlarged vadially without the formation of tapetal plasmodium in this type. It is suggested that the different mechanism on pollen sterility has something to do with the cytoplasmic types which are responsible for the expression of complete sterile plants. The starch reaction in the middle layer and the endothecium of the anther also correlated with the type of tapetal abnormality. (Kobatake, H.)

  3. K-Domain Splicing Factor OsMADS1 Regulates Open Hull Male Sterility in Rice

    Directory of Open Access Journals (Sweden)

    SUN Lian-ping

    2015-09-01

    Full Text Available We identified the rice floral organ development mutant, termed as open hull and male sterile 1 (ohms1, from the progeny of the indica restorer line Zhonghui 8015 treated with 60Co γ-ray irradiation. The ohms1 mutant exhibited an open hull and lemma- and palea-like structure conversion between the anthers and stigma, which resulted in the ohms1 mutant spikelet showing ‘tridentate lemma’. The ohms1 mutant was entirely sterile but had 60%–70% fertile pollen. Genetic analysis and gene mapping showed that ohms1 was controlled by a single recessive gene, and the mutant gene was fine-mapped to a 42-kb interval on the short arm of chromosome 3 between markers KY2 and KY29. Sequence analysis of the four open reading frames in this region revealed that the mutant carried a single nucleotide transformation (A to G at the last base of the fifth intron, which was likely corresponded to ohms1 phynotype, in an MIKC type MADS-box gene OsMADS1 (LOC_Os03g11614. Enzyme digestion and cDNA sequencing further indicated that the variable splicing was responsible for the deletion of the sixth exon in ohms1, but no structural changes in the MADS domain or amino acid frame shifts appeared. Additionally, real-time fluorescent quantitative PCR analysis showed that the OsMADS1 expression level decreased significantly in the ohms1 mutant. The expression levels of rice flowering factors and floral glume development-related genes also changed significantly. These results demonstrate that OsMADS1 may play an important role in rice floral organ development, particularly in floral glume development and floret primordium differentiation.

  4. Study of genetic variation at the level of DNA between normal and sterilized potato tuber moth males (phthorimaea operculella, zeller)

    International Nuclear Information System (INIS)

    Ammouneh, H.; Makee, H.; Idris, E.

    2009-06-01

    The main objective of current study was to determine the genetic variation at the level of DNA between the normal and sterilized potato tuber moth males. The required mating experiments were carried out to obtain partially sterilized males at 150 Gy and their offspring. Some biological factors of these males were estimated and compared to their unirradiated siblings. To acquire good quality and quantity of DNA for the AFLP technique, several methods were undertaken to isolate DNA of potato tuber moth male from different developmental stages especially from adult stage. However, a method called Modified M5 was used. By Modified M5, which required phenol for the isolation of DNA, in some samples 8 to 12 μg were obtained from one insect with 95-100% purity. In our study, AFLP technique was used to analyze the DNA samples of irradiated and unirradiated males from required mating. The result analysis showed that there was a clear genetic variability between examined individuals. However, the relationship between unirradiated F1 and F2 males was stronger than that between irradiated males. Thus, our result demonstrates that the AFLP could be efficiently utilized for studying genetic variation between insect species or between individuals of the same line which have biological differences induced by several factors such as irradiation. Moreover, this technique could enhance the effectiveness of sterile insect technique by using the AFLP in the monitoring system of released insects. (author)

  5. Prerelease exposure to methyl eugenol increases the mating competitiveness of sterile males of the oriental fruit fly (Diptera: Tephritidae) in a Hawaiian orchard.

    Science.gov (United States)

    McInnis, D; Kurashima, R; Shelly, T; Komatsu, J; Edu, J; Pahio, E

    2011-12-01

    Males of the oriental fruit fly, Bactrocera dorsalis (Hendel), are strongly attracted to methyl eugenol (ME), and recent work demonstrated that ingestion of this chemical enhances male mating success, apparently owing its role as a precursor in the synthesis of the male sex pheromone. The current study expanded upon earlier laboratory and field-cage experiments by assessing whether prerelease exposure to ME increased the mating competitiveness of mass-reared, sterile males in Hawaiian orchards. Releases of sterile males from a pupal color-based sexing strain were made weekly in two fruit orchards over 8 mo, with the sterile males at one site given ME for 24 h before release (treated) and the sterile males at the other site given no ME before release (control). Fruits were collected periodically during the study period, and eggs were dissected and incubated to score hatch rate. At both sites, releases of sterile males increased the proportion of unhatched eggs well above prerelease levels, but the incidence of egg sterility was consistently, and statistically, greater in the orchard receiving ME-exposed males. Computed over the entire release period, the average value of Fried's competitive index (that characterizes the mating success of sterile males relative to their wild counterparts) for ME-treated males was 3.5 times greater than that for control males, although this difference was not statistically significant. However, when computed over the period during which egg sterility values were elevated and stable, presumably when females inseminated before the releases were rare or absent, the competitive indices were significantly higher for ME-treated sterile males. The implications of these results for implementing the Sterile Insect Technique against this species are discussed.

  6. Construction of a multicontrol sterility system for a maize male-sterile line and hybrid seed production based on the ZmMs7 gene encoding a PHD-finger transcription factor.

    Science.gov (United States)

    Zhang, Danfeng; Wu, Suowei; An, Xueli; Xie, Ke; Dong, Zhenying; Zhou, Yan; Xu, Liwen; Fang, Wen; Liu, Shensi; Liu, Shuangshuang; Zhu, Taotao; Li, Jinping; Rao, Liqun; Zhao, Jiuran; Wan, Xiangyuan

    2018-02-01

    Although hundreds of genetic male sterility (GMS) mutants have been identified in maize, few are commercially used due to a lack of effective methods to produce large quantities of pure male-sterile seeds. Here, we develop a multicontrol sterility (MCS) system based on the maize male sterility 7 (ms7) mutant and its wild-type Zea mays Male sterility 7 (ZmMs7) gene via a transgenic strategy, leading to the utilization of GMS in hybrid seed production. ZmMs7 is isolated by a map-based cloning approach and encodes a PHD-finger transcription factor orthologous to rice PTC1 and Arabidopsis MS1. The MCS transgenic maintainer lines are developed based on the ms7-6007 mutant transformed with MCS constructs containing the (i) ZmMs7 gene to restore fertility, (ii) α-amylase gene ZmAA and/or (iii) DNA adenine methylase gene Dam to devitalize transgenic pollen, (iv) red fluorescence protein gene DsRed2 or mCherry to mark transgenic seeds and (v) herbicide-resistant gene Bar for transgenic seed selection. Self-pollination of the MCS transgenic maintainer line produces transgenic red fluorescent seeds and nontransgenic normal colour seeds at a 1:1 ratio. Among them, all the fluorescent seeds are male fertile, but the seeds with a normal colour are male sterile. Cross-pollination of the transgenic plants to male-sterile plants propagates male-sterile seeds with high purity. Moreover, the transgene transmission rate through pollen of transgenic plants harbouring two pollen-disrupted genes is lower than that containing one pollen-disrupted gene. The MCS system has great potential to enhance the efficiency of maize male-sterile line propagation and commercial hybrid seed production. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  7. DETERMINATION OF FERTILITY AND POLLEN VIABILITY OF BREEDING LINE OF PATTYUPAN SQUASH WITH MALE STERILITY OF FUNCTIONAL TYPE

    Directory of Open Access Journals (Sweden)

    A. M. Shantasov

    2014-01-01

    Full Text Available This article describes the features of the development of male sterility trait of functional type in patty"pan squash. The viability of pollen grains in different periods of vegetation was studied. The determined fertility ability of pollen can be used for hybrid seed production of different varieties of pumpkin.

  8. Comparative studies of mitochondrial proteomics reveal an intimate protein network of male sterility in wheat (Triticum aestivum L.)

    Science.gov (United States)

    Wang, Shuping; Zhang, Gaisheng; Zhang, Yingxin; Song, Qilu; Chen, Zheng; Wang, Junsheng; Guo, Jialin; Niu, Na; Wang, Junwei; Ma, Shoucai

    2015-01-01

    Plant male sterility has often been associated with mitochondrial dysfunction; however, the mechanism in wheat (Triticum aestivum L.) has not been elucidated. This study set out to probe the mechanism of physiological male sterility (PHYMS) induced by the chemical hybridizing agent (CHA)-SQ-1, and cytoplasmic male sterility (CMS) of wheat at the proteomic level. A total of 71 differentially expressed mitochondrial proteins were found to be involved in pollen abortion and further identified by MALDI-TOF/TOF MS (matrix-assisted laser desorption/ionization-time of fight/time of flight mass spectrometry). These proteins were implicated in different cellular responses and metabolic processes, with obvious functional tendencies toward the tricarboxylic acid cycle, the mitochondrial electron transport chain, protein synthesis and degradation, oxidation stress, the cell division cycle, and epigenetics. Interactions between identified proteins were demonstrated by bioinformatics analysis, enabling a more complete insight into biological pathways involved in anther abortion and pollen defects. Accordingly, a mitochondria-mediated male sterility protein network in wheat is proposed; this network was further confirmed by physiological data, RT-PCR (real-time PCR), and TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling) assay. The results provide intriguing insights into the metabolic pathway of anther abortion induced by CHA-SQ-1 and also give useful clues to identify the crucial proteins of PHYMS and CMS in wheat. PMID:26136264

  9. Mitochondrial Dysfunction Causes Oxidative Stress and Tapetal Apoptosis in Chemical Hybridization Reagent-Induced Male Sterility in Wheat

    Directory of Open Access Journals (Sweden)

    Shuping Wang

    2018-01-01

    Full Text Available Male sterility in plants has been strongly linked to mitochondrial dysfunction. Chemical hybridization agent (CHA-induced male sterility is an important tool in crop heterosis. Therefore, it is important to better understand the relationship between mitochondria and CHA-induced male sterility in wheat. This study reports on the impairment of mitochondrial function duo to CHA-SQ-1, which occurs by decreasing cytochrome oxidase and adenosine triphosphate synthase protein levels and theirs activities, respiratory rate, and in turn results in the inhibition of the mitochondrial electron transport chain (ETC, excessive production of reactive oxygen species (ROS and disruption of the alternative oxidase pathway. Subsequently, excessive ROS combined with MnSOD defects results in damage to the mitochondrial membrane, followed by ROS release into the cytoplasm. The microspores underwent severe oxidative stress during pollen development. Furthermore, chronic oxidative stress, together with the overexpression of type II metacaspase, triggered premature tapetal apoptosis, which resulted in pollen abortion. Accordingly, we propose a metabolic pathway for mitochondrial-mediated male sterility in wheat, which provides information on the molecular events underlying CHA-SQ-1-induced abortion of anthers and may serve as an additional guide to the practical application of hybrid breeding.

  10. Semiochemical mediated enhancement of males to complement sterile insect technique in management of the tephritid pest Bactrocera tryoni (Froggatt)

    Science.gov (United States)

    Queensland fruit fly, Bactrocera tryoni (Froggatt), is the most significant pest of Australia’s $9 billion horticulture industry. The sterile insect technique (SIT) and male annihilation technique (MAT) based on traps baited with a synthetic analogue of raspberry ketone (RK) are two of the most effe...

  11. Tubulin cytoskeleton during microsporogenesis in the male-sterile genotype of Allium sativum and fertile Allium ampeloprasum L.

    Science.gov (United States)

    Tchórzewska, Dorota; Deryło, Kamil; Błaszczyk, Lidia; Winiarczyk, Krystyna

    2015-12-01

    Microsporogenesis in garlic. The male-sterile Allium sativum (garlic) reproduces exclusively in the vegetative mode, and anthropogenic factors seem to be the cause of the loss of sexual reproduction capability. There are many different hypotheses concerning the causes of male sterility in A.sativum; however, the mechanisms underlying this phenomenon have not been comprehensively elucidated.Numerous attempts have been undertaken to understand the causes of male sterility, but the tubulin cytoskeleton in meiotically dividing cells during microsporogenesis has never been investigated in this species. Using sterile A.sativum genotype L13 and its fertile close relative A. ampeloprasum (leek), we have analysed the distribution of the tubulin cytoskeleton during microsporogenesis. We observed that during karyokinesis and cytokinesis, in both meiotic divisions I and II, the microtubular cytoskeleton in garlic L13 formed configurations that resembled tubulin arrangement typical of monocots. However, the tubulin cytoskeleton in garlic was distinctly poorer (composed of a few MT filaments) compared with that found in meiotically dividing cells in A. ampeloprasum. These differences did not affect the course of karyogenesis, chondriokinesis, and cytokinesis, which contributed to completion of microsporogenesis, but there was no further development of the male gametophyte. At the very beginning of the successive stage of development of fertile pollen grains, i.e. gametogenesis, there were disorders involving the absence of a normal cortical cytoskeleton and dramatically progressive degeneration of the cytoplasm in garlic. Therefore,we suggest that, due to disturbances in cortical cytoskeleton formation at the very beginning of gametogenesis, the intracellular transport governed by the cytoskeleton might be perturbed, leading to microspore decay in the male-sterile garlic genotype.

  12. A comparison of the vegetative growth of male-sterile and hermaphroditic lines of Plantago lanceolata in relation to N supply

    NARCIS (Netherlands)

    Poot, P.; Van den Broek, T.; Van Damme, J.M.M.; Lambers, H.

    1997-01-01

    Gynodioecy is a dimorphic breeding system in which hermaphrodites coexist with male steriles in natural populations. Theoretical models predict that without any compensation in female fitness, male steriles will quickly disappear from a population. The amount of compensation required depends upon

  13. Assessment of knowledge and perception regarding male sterilization (Non-Scalpel Vasectomy among community health workers in Jharkhand, India

    Directory of Open Access Journals (Sweden)

    Swati Mahapatra

    2014-12-01

    Full Text Available Introduction: In India, community health workers are the main source of information for family planning services and male population want to interact and discuss with them to clear their doubts about male oriented family planning methods. Objective: The objective of the study was to assess the knowledge and perception of community health workers regarding the modern male sterilization method. Methodology: This was a cross-sectional study conducted in Simdega district of Jharkhand. The target population was the community health workers and randomly selected from four randomly selected from blocks out of total seven in the district. A self-administered quantitative questionnaire was used for data collection comprising questions related to knowledge and perception of community health workers about modern male sterilization method. Results: 43% CHWs didn’t know that this method is different from traditional male sterilization method and around 62% thought man’s sexual performance get affected after NSV and 77% did not have any idea about time required to resume normal work. Conclusions: The poor knowledge and wrong perception could be one of the main reasons for poor male participation in family planning process in India.

  14. Induction of Tetraploid Male Sterile Tagetes erecta by Colchicine Treatment and Its Application for Interspecific Hybridization

    Directory of Open Access Journals (Sweden)

    Yanhong He

    2016-09-01

    Full Text Available Tagetes erecta is an annual multifunctional plant which can be cultivated under a broad range of climatic conditions. Polyploidization and interspecific hybridization are applied to facilitate breeding cultivars of T. erecta with improved ornamental qualities. Colchicine treatment to the germinating seeds was proved to be a useful tool for chromosome doubling of the male sterile two-type line ‘M525AB’, with the resulting frequency of polyploid seedlings ranging from 88.89% (following 0.05% w/v colchicine applied for a 3–6 h exposure period to a maximum of 100.00% (following 0.1% for 3–6 h, or 0.2% for 3 h. Morphological observation, stomatal size and density analysis, flow cytometric analysis and chromosome counting were conducted to identify the tetraploid plants. Distinctive morphological changes were observed in a notable proportion of polyploid plants. The colchicine-treated polyploid T. erecta plants showed dwarfed and more robust growth, thicker, larger and greener leaves, larger inflorescences and florets. The mutant plants identified through morphological observation all aligned as polyploid plants, thus morphological observation could be an effective method for the detection of polyploidy. The polyploid plants had significant larger stomata size over the abaxial leaf surface, whereas the density of stomata distribution was remarkably reduced. The survival rate of tetraploid cuttings (i.e. 38% was greatly reduced compared to that of diploid plants. The fertility of tetraploid plants was also decreased, as shown by cross-pollination yields. Interspecific hybridizations between colchicine-induced tetraploid plants of a male sterile T. erecta line and the naturally tetraploid fully fertile Tagetes patula species resulted in hybrid progeny. Most of these hybrids displayed the dwarfed growth stature and compact, larger-flower morphology which is the typical ideotype of herbaceous flowers. Thus, polyploidization may be employed

  15. Changes in blood testosterone concentrations after surgical and chemical sterilization of male free-roaming dogs in southern Chile.

    Science.gov (United States)

    Vanderstichel, R; Forzán, M J; Pérez, G E; Serpell, J A; Garde, E

    2015-04-01

    There is a growing interest in chemical sterilization as an alternative to surgical castration in large-scale sterilization campaigns to control canine populations. An important step toward understanding the short-term and long-term effects of chemical sterilants is to determine their impact on blood testosterone concentrations, particularly as these could influence dog behavior after treatment. A field trial was conducted with 118 free-roaming male dogs in the Chilean Patagonia, where 36 dogs were chemically sterilized using EsterilSol, 39 dogs were surgically castrated, and 43 dogs remained intact as controls. Blood testosterone levels were determined at four time periods: on enrollment 6 months before treatment (t-6m), at the time of treatment (t0, within one hour after surgical castration or chemical sterilization and during a concurrent 2-week period for the control group), four (t+4m), and six (t+6m) months after treatment. Intrinsic and temporal factors were evaluated; age was significantly associated with testosterone, where dogs 2- to 4-year-old had the highest testosterone concentrations (P = 0.036), whereas body weight and body condition scores were not associated with testosterone; testosterone concentration was not influenced by time of day, month, or season. After treatment (t+4m and t+6m), all of the surgically castrated dogs had testosterone concentrations below 1.0 ng/mL. On the basis of this cut point (sterilized dogs at both t+4m and t+6m; it remained low for 22% of dogs at both t+4m and t+6m; it was unchanged at t+4m but low at t+6m in 9% of dogs; and, it was low at t+4m but reverted back to unchanged at t+6m in one dog (3%). Incidentally, testosterone in chemically sterilized dogs increased dramatically within 1 hour of treatment (t0), more than doubling (131%) the concentration of control dogs at the time of treatment (t0), likely because of severe necrosis of interstitial cells. The use of EsterilSol as a method of sterilizing dogs had a

  16. Mode of inheritance of irradiation induced dwarfism and male sterility in the tomato, Lycopersicon esculentum

    International Nuclear Information System (INIS)

    Garofalo, J.F.

    1975-01-01

    Seedlings of the Louisiana tomato cultivar ''Pelican'' were irradiated in the cotyledonary stage with 10,000 roentgen (R) of gamma radiation from 60 Co at 1.67 R/min by Dr. Milton J. Constantin, Comparative Animal Research Laboratory operated by the University of Tennessee for the Atomic Energy Commission. From these irradiated plants one dwarf and six stamenless mutants were selected and propagated. In 1973 to 1974 a genetic study was conducted to determine the mode of inheritance of these mutant characters. Also a combining ability study was conducted to determine the potential value of the dwarf mutant as a parent in the production of F 1 hybrid seed. The results of the genetic study showed that the induced dwarf character was simply inherited and recessive. Results indicate that this gene is probably located at a locus different from that of genes controlling dwarfism in other tomato lines. The combining ability study showed that this dwarf mutant is of little value as a breeding parent. The genetic study of the stamenless lines showed this character to be simply inherited and recessive. It was also shown that the gene controlling male sterility is located at the same locus in the lines L 39 and L 43, and it is assumed that the same locus is involved in all six lines. The stamenless lines have, as far as has been observed, retained the good combining ability of the original parent cultivar ''Pelican''

  17. Association of nad7a Gene with Cytoplasmic Male Sterility in Pigeonpea

    Directory of Open Access Journals (Sweden)

    Pallavi Sinha

    2015-07-01

    Full Text Available Cytoplasmic male sterility (CMS has been exploited in the commercial pigeonpea [ (L. Millsp.] hybrid breeding system; however, the molecular mechanism behind this system is unknown. To understand the underlying molecular mechanism involved in A CMS system derived from (Haines Maesen, 34 mitochondrial genes were analyzed for expression profiling and structural variation analysis between CMS line (ICRISAT Pigeonpea A line, ICPA 2039 and its cognate maintainer (ICPB 2039. Expression profiling of 34 mitochondrial genes revealed nine genes with significant fold differential gene expression at ≤ 0.01, including one gene, , with 1366-fold higher expression in CMS line as compared with the maintainer. Structural variation analysis of these mitochondrial genes identified length variation between ICPA 2039 and ICPB 2039 for (subunit of gene. Sanger sequencing of and genes in the CMS and the maintainer lines identified two single nucleotide polymorphisms (SNPs in upstream region of and a deletion of 10 bp in in the CMS line. Protein structure evaluation showed conformational changes in predicted protein structures for between ICPA 2039 and ICPB 2039 lines. All above analyses indicate association of gene with the CMS for A cytoplasm in pigeonpea. Additionally, one polymerase chain reaction (PCR based Indel marker ( has been developed and validated for testing genetic purity of A derived CMS lines to strengthen the commercial hybrid breeding program in pigeonpea.

  18. F1 HYBRIDS BREEDING OF RADISH (RAPHANUS SATIVUS L. ON THE BASIS OF MALE STERILE LINES

    Directory of Open Access Journals (Sweden)

    G. F. Monakhos

    2015-01-01

    Full Text Available The line fixers of sterility from the other pairs with genotype TsitNrfrf are encouraged to use for off-patent biological copyright protection paternal pollinating lines. In this case, the F1 hybrids will always have a TsitSrfrf genotype and will be sterile, which makes it impossible to obtain F2 progeny.

  19. Sporoderm infrastructural and cytochemical modifications in cytoplasmic male sterile broad-bean (Vicia faba L.

    Directory of Open Access Journals (Sweden)

    Jean-Claude Audran

    2014-01-01

    Full Text Available A comparative study of mature sporoderms of sterile and fertile pollen grains was performed using electron microscopic techniques. In sterile pollen grains, intine is lacking; ectexine sculpture is reduced and tectum is overlaid by membranous systems. Infratectal texture is compact and a sporopollenin granulous mass is obturing the aperture central region. Endexine reacts with proteins and acidic carbohydrates tests.

  20. Sterilization of males Diabrotica speciosa (Coleoptera: Chrysomelidae) with gamma irradiation for control in cultures of economic importance

    International Nuclear Information System (INIS)

    Araujo, Marcio Martins

    2017-01-01

    Diabrotica speciosa (Germar, 1824), causes direct and indirect damage on crops by feeding and acting as virus vector for diverse groups of plants. The main control form is the use of agrochemicals so, aiming to manage the population without environment impact, the present work had as objective to determine the dose of gamma radiation that provides male sterility, its foliar consumption and gonads histological changes. Adult males were submitted to gamma radiation ( 60 Co) on the third day after emergence at doses of 0, 25, 50, 75 and 100 Gy at 0,808 KGy/ hour rate, totaling 20 replicates/ dose. The sterilizing dose was based on the fertility of sexually mature non-irradiated females mated by irradiated males. The couples were individualized in 'arenas' and fed with leaflets Phaseolus vulgaris L. with black gauze moistened for oviposition. Eggs were treated and arranged in plastic containers lined with filter paper. After hatching, larvae were transferred to a larger container with a cover cap containing fine vermiculite and maize seedlings (Zea mays L.), which were replaced every 10 days, until adult emergence. After the 4 th day of irradiation, a leaf disc with 3.2 cm in diameter was available for 24 hours for each couple. The discs were scanned and analyzed in ImageJ software. To evaluate the gonads, 3 males with 8 days of age were used per dose. They were dissected in PBS, through the Hematoxylin-Eosin technique the laminas were evaluated under an optical microscope. We observed that male sterility occurred from 75 Gy and the average longevity of this group was of 12.5 days. Consumption of the leaf area by couples composed by a sterile male was 42.9% and the testicular histological analysis demonstrated tissue disorganisation and gaps between germ cells at the highest doses of 75 Gy and 100 Gy. (author)

  1. Pre-Release Consumption of Methyl Eugenol Increases the Mating Competitiveness of Sterile Males of the Oriental Fruit Fly, Bactrocera dorsalis, in Large Field Enclosures

    Science.gov (United States)

    Shelly, Todd E.; Edu, James; McInnis, Donald

    2010-01-01

    The sterile insect technique may be implemented to control populations of the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), when environmental concerns preclude widespread use of chemical attractants or toxicants. The goal of the present study was to evaluate whether the mating competitiveness of sterile B. dorsalis males could be increased via pre-release feeding on methyl eugenol. Males of the oriental fruit fly are strongly attracted to this plant-borne compound, which they ingest and use in the synthesis of the sex pheromone. Previous studies conducted in the laboratory and small field-cages have shown that males given methyl eugenol produce a more attractive pheromone for females and have a higher mating success rate than males denied methyl eugenol. Here, levels of egg sterility were compared following the release of wild-like flies and either methyl eugenol-fed (treated) or methyl eugenol-deprived (control) sterile males in large field enclosures at four over flooding ratios ranging from 5:1 to 60:1 (sterile: wild-like males). Treated sterile males were fed methyl eugenol for 1–4 h (depending on the over flooding ratio tested) 3 d prior to release. Eggs were dissected from introduced fruits (apples), incubated in the laboratory, and scored for hatch rate. The effect of methyl eugenol was most pronounced at lower over flooding ratios. At the 5:1 and 10:1 over flooding ratios, the level of egg sterility observed for treated, sterile males was significantly greater than that observed for control, sterile males. In addition, the incidence of egg sterility reported for treated sterile males at these lower over flooding ratios was similar to that noted for treated or control sterile males at the 30:1 or 60:1 over flooding ratios. This latter result, in particular, suggests that pre-release feeding on methyl eugenol allows for a reduction in the number of sterile flies that are produced and released, thus increasing the cost

  2. Pre-release consumption of methyl eugenol increases the mating competitiveness of sterile males of the oriental fruit fly, Bactrocera dorsalis, in large field enclosures.

    Science.gov (United States)

    Shelly, Todd E; Edu, James; McInnis, Donald

    2010-01-01

    The sterile insect technique may be implemented to control populations of the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), when environmental concerns preclude widespread use of chemical attractants or toxicants. The goal of the present study was to evaluate whether the mating competitiveness of sterile B. dorsalis males could be increased via pre-release feeding on methyl eugenol. Males of the oriental fruit fly are strongly attracted to this plant-borne compound, which they ingest and use in the synthesis of the sex pheromone. Previous studies conducted in the laboratory and small field-cages have shown that males given methyl eugenol produce a more attractive pheromone for females and have a higher mating success rate than males denied methyl eugenol. Here, levels of egg sterility were compared following the release of wild-like flies and either methyl eugenol-fed (treated) or methyl eugenol-deprived (control) sterile males in large field enclosures at four over flooding ratios ranging from 5:1 to 60:1 (sterile: wild-like males). Treated sterile males were fed methyl eugenol for 1-4 h (depending on the over flooding ratio tested) 3 d prior to release. Eggs were dissected from introduced fruits (apples), incubated in the laboratory, and scored for hatch rate. The effect of methyl eugenol was most pronounced at lower over flooding ratios. At the 5:1 and 10:1 over flooding ratios, the level of egg sterility observed for treated, sterile males was significantly greater than that observed for control, sterile males. In addition, the incidence of egg sterility reported for treated sterile males at these lower over flooding ratios was similar to that noted for treated or control sterile males at the 30:1 or 60:1 over flooding ratios. This latter result, in particular, suggests that pre-release feeding on methyl eugenol allows for a reduction in the number of sterile flies that are produced and released, thus increasing the cost

  3. A randomized, controlled, multicenter contraceptive efficacy clinical trial of the intravas device, a nonocclusive surgical male sterilization

    Science.gov (United States)

    Lu, Wen-Hong; Liang, Xiao-Wei; Gu, Yi-Qun; Wu, Wei-Xiong; Bo, Li-Wei; Zheng, Tian-Gui; Chen, Zhen-Wen

    2014-01-01

    Because of unavoidable complications of vasectomy, this study was undertaken to assess the efficacy and safety of male sterilization with a nonobstructive intravas device (IVD) implanted into the vas lumen by a mini-surgical method compared with no-scalpel vasectomy (NSV). IVDs were categorized into two types: IVD-B has a tail used for fixing to the vas deferens (fixed wing) whereas IVD-A does not. A multicenter prospective randomized controlled clinical trial was conducted in China. The study was comprised of 1459 male volunteers seeking vasectomy who were randomly assigned to the IVD-A (n = 487), IVD-B (n = 485) or NSV (n = 487) groups and underwent operation. Follow-up included visits at the 3rd–6th and 12th postoperative months. The assessments of the subjects involved regular physical examinations (including general and andrological examinations) and semen analysis. The subjects’ partners also underwent monitoring for pregnancy by monthly interviews regarding menstruation and if necessary, urine tests. There were no significant differences in pregnancy rates (0.65% for IVD-A, 0 for IVD-B and 0.21% for NSV) among the three groups (P > 0.05). The cumulative rates of complications at the 12th postoperative month were zero, 0.9% and 1.7% in the three groups, respectively. In conclusion, IVD male sterilization exhibits a low risk of long-term adverse events and was found to be effective as a male sterilization method, similar to the NSV technique. IVD male sterilization is expected to be a novel contraceptive method. PMID:24589454

  4. A randomized, controlled, multicenter contraceptive efficacy clinical trial of the intravas device, a nonocclusive surgical male sterilization

    Directory of Open Access Journals (Sweden)

    Wen-Hong Lu

    2014-06-01

    Full Text Available Because of unavoidable complications of vasectomy, this study was undertaken to assess the efficacy and safety of male sterilization with a nonobstructive intravas device (IVD implanted into the vas lumen by a mini-surgical method compared with no-scalpel vasectomy (NSV. IVDs were categorized into two types: IVD-B has a tail used for fixing to the vas deferens (fixed wing whereas IVD-A does not. A multicenter prospective randomized controlled clinical trial was conducted in China. The study was comprised of 1459 male volunteers seeking vasectomy who were randomly assigned to the IVD-A (n = 487, IVD-B (n = 485 or NSV (n = 487 groups and underwent operation. Follow-up included visits at the 3 rd -6 th and 12 th postoperative months. The assessments of the subjects involved regular physical examinations (including general and andrological examinations and semen analysis. The subjects' partners also underwent monitoring for pregnancy by monthly interviews regarding menstruation and if necessary, urine tests. There were no significant differences in pregnancy rates (0.65% for IVD-A, 0 for IVD-B and 0.21% for NSV among the three groups (P > 0.05. The cumulative rates of complications at the 12 th postoperative month were zero, 0.9% and 1.7% in the three groups, respectively. In conclusion, IVD male sterilization exhibits a low risk of long-term adverse events and was found to be effective as a male sterilization method, similar to the NSV technique. IVD male sterilization is expected to be a novel contraceptive method.

  5. A randomized, controlled, multicenter contraceptive efficacy clinical trial of the intravas device, a nonocclusive surgical male sterilization.

    Science.gov (United States)

    Lu, Wen-Hong; Liang, Xiao-Wei; Gu, Yi-Qun; Wu, Wei-Xiong; Bo, Li-Wei; Zheng, Tian-Gui; Chen, Zhen-Wen

    2014-01-01

    Because of unavoidable complications of vasectomy, this study was undertaken to assess the efficacy and safety of male sterilization with a nonobstructive intravas device (IVD) implanted into the vas lumen by a mini-surgical method compared with no-scalpel vasectomy (NSV). IVDs were categorized into two types: IVD-B has a tail used for fixing to the vas deferens (fixed wing) whereas IVD-A does not. A multicenter prospective randomized controlled clinical trial was conducted in China. The study was comprised of 1459 male volunteers seeking vasectomy who were randomly assigned to the IVD-A (n = 487), IVD-B (n = 485) or NSV (n = 487) groups and underwent operation. Follow-up included visits at the 3 rd -6 th and 12 th postoperative months. The assessments of the subjects involved regular physical examinations (including general and andrological examinations) and semen analysis. The subjects' partners also underwent monitoring for pregnancy by monthly interviews regarding menstruation and if necessary, urine tests. There were no significant differences in pregnancy rates (0.65% for IVD-A, 0 for IVD-B and 0.21% for NSV) among the three groups (P > 0.05). The cumulative rates of complications at the 12 th postoperative month were zero, 0.9% and 1.7% in the three groups, respectively. In conclusion, IVD male sterilization exhibits a low risk of long-term adverse events and was found to be effective as a male sterilization method, similar to the NSV technique. IVD male sterilization is expected to be a novel contraceptive method.

  6. Transcriptomic Profiling Reveals Complex Molecular Regulation in Cotton Genic Male Sterile Mutant Yu98-8A.

    Directory of Open Access Journals (Sweden)

    Weiping Fang

    Full Text Available Although cotton genic male sterility (GMS plays an important role in the utilization of hybrid vigor, its precise molecular mechanism remains unclear. To characterize the molecular events of pollen abortion, transcriptome analysis, combined with histological observations, was conducted in the cotton GMS line, Yu98-8A. A total of 2,412 genes were identified as significant differentially expressed genes (DEGs before and during the critical pollen abortion stages. Bioinformatics and biochemical analysis showed that the DEGs mainly associated with sugars and starch metabolism, oxidative phosphorylation, and plant endogenous hormones play a critical and complicated role in pollen abortion. These findings extend a better understanding of the molecular events involved in the regulation of pollen abortion in genic male sterile cotton, which may provide a foundation for further research studies on cotton heterosis breeding.

  7. Characterizing and marker-assisting a novel chili pepper (Capsicum annuum L.) yellow bud mutant with cytoplasmic male sterility.

    Science.gov (United States)

    Sun, G S; Dai, Z L; Bosland, P W; Wang, Q; Sun, C Q; Zhang, Z C; Ma, Z H

    2017-02-23

    Cytoplasmic male sterility (CMS) in pepper is a better way to produce hybrid seeds compared to manual production. We used the two sequence characterized amplified region (SCAR) markers (CRF-SCAR and CMS-SCAR 130 ) in CMS pepper, to identify the genotype. We assembled two CMS yellow bud mutants (YBM; YBM12-A and YBM12-B). This mutation in leaf color is controlled by a single dominant nuclear gene. The aim was to create a new hybrid seed production method that reduces the costs and increases F 1 hybrid seed purity. The results suggest that the CRF-SCAR and CMS-SCAR 130 markers can be used together in multiple generations to screen for restorer or maintainer genes. We found the marker linked to the restorer gene (Rf) in the C-line and F 1 hybrids, as well as partially in the F 2 generation, whereas it was not found in the sterile YBM12-A or the maintainer line YBM12-B. In the F 2 population, sterility and fertility segregated at a 3:1 ratio based on the CRF-SCAR marker. A 130 bp fragment was produced in the YBM12-A, F 1 , and F 2 populations, suggesting that these lines contained sterile cytoplasm. A 140 bp fragment present in the YBM12-B and C-line indicated that these lines contained normal cytoplasm. In addition, we identified some morphological characters distinguishing sterile and fertile buds and flowers that may be linked to the sterility gene. If more restorer lines are identified, CMS expressing the YBM trait can be used in hybrid seed production.

  8. Meiotic behavior of economically important plant species: the relationship between fertility and male sterility

    Directory of Open Access Journals (Sweden)

    Maria Suely Pagliarini

    2000-12-01

    Full Text Available Meiosis is an event of high evolutionary stability which culminates in a reduction of chromosome number. The normal and harmonious course of meiosis ensures gamete viability. The cytologic events of gametogenesis are controlled by a large number of genes that act from premeiotic to postmeiotic mitosis. Mutations in these genes cause anomalies that may impair fertility, and many abnormalities affecting plant fertility or causing total male sterility have been detected during the evaluation of meiotic behavior in some species. Some of these abnormalities have been frequently described in the literature, while others have not been previously reported. The most frequent abnormalities found in the species analyzed were irregular chromosome segregation, cytomixis, chromosome stickiness, mixoploidy, chromosome fragmentation, syncyte formation, abnormal spindles, and failure of cytokinesis. Uncommon abnormalities, such as chromosome elimination during microsporogenesis, were found in one species. Original meiotic mutations affecting different steps of meiosis were also observed in these species, especially in maize, Paspalum and soybean. Some mutants present characteristics that may be exploited successfully in breeding programs because they cause total male sterility.A meiose é um evento de alta estabilidade evolucionária que culmina na redução do número de cromossomos. O curso normal e harmonioso da meiose garante a viabilidade gamética. Os eventos citológicos da gametogênese são controlados por um grande número de genes que atuam desde as mitoses pré-meióticas até as pós-meióticas. Mutações nestes genes causam anomalias que podem afetar a fertilidade. Durante a avaliação do comportamento meiótico em algumas espécies de plantas, muitas anormalidades que afetaram a fertilidade ou causaram total macho-esterilidade foram detectadas. Algumas das anormalidades encontradas já eram descritas na literatura, enquanto outras eram

  9. Marker-Assisted Backcrossing to Develop an Elite Cytoplasmic Male Sterility Line in Rice

    Directory of Open Access Journals (Sweden)

    Asadollah Ahmadikhah

    2015-07-01

    Full Text Available Cytoplasmic male sterility (CMS is a cornerstone of hybrid production in many crops. In three-line hybrid systems, use of CMS, maintainer, and fertility restorer lines is necessary for production of hybrid seeds. Limited resources of CMS and low variation of CMS lines cause genetic vulnerability to pathogens. Therefore, diversifying the CMS sources is indispensible for a sustainable production system of hybrid seed. In this study, we attempted for the first time to transfer CMS into maintainer line Yosen B in restricted generations using the marker-assisted backcrossing (MABC method. The resultant F hybrid of IR68897 A/Yosen B cross was backcrossed to Yosen B, and CMS plants in each backcross generation (from BCF to BCF were selected based on phenotyping test and MABC. Molecular assessment of backcross progenies was conducted using a mitochondrial CMS-specific marker and 34 polymorphic nuclear simple-sequence repeat (SSR markers in early generations (from BCF to BCF and was continued using 9 additional SSRs and 82 inter-simple sequence repeat (ISSR markers in BCF. A MABC strategy could successfully recover the recurrent parent genome (RPG in BCF generation, and decreased heterozygosity of final CMS plants. Restorability test with known wild-abortive restorer lines (viz. IR36 and IR24 showed that combination of Yosen A × IR24 could produce highly fertile F hybrid. Evaluation of some important agronomic traits of the final CMS line (BCF at field condition showed that it was comparable to the original maintainer fertile counterpart. Phenotypic and marker-assisted selections could considerably decrease the time needed for full recovery of RPG so that final CMS line could show a high similarity to original fertile counterpart.

  10. Mitochondrial ORF79 levels determine pollen abortion in cytoplasmic male sterile rice.

    Science.gov (United States)

    Kazama, Tomohiko; Itabashi, Etsuko; Fujii, Shinya; Nakamura, Takahiro; Toriyama, Kinya

    2016-03-01

    Cytoplasmic male sterility (CMS) is an important agricultural trait characterized by lack of functional pollen, and caused by ectopic and defective mitochondrial gene expression. The pollen function in CMS plants is restored by the presence of nuclear-encoded restorer of fertility (Rf) genes. Previously, we cloned Rf2, which restores the fertility of Lead Rice (LD)-type CMS rice. However, neither the function of Rf2 nor the identity of the mitochondrial gene causing CMS has been determined in LD-CMS rice. Here, we show that the mitochondrial gene orf79 acts as a CMS-associated gene in LD-CMS rice, similar to its role in BT-CMS rice originating from Chinsurah Boro II, and Rf2 weakly restores fertility in BT-CMS rice. We also show that RF2 promotes degradation of atp6-orf79 RNA in a different manner from that of RF1, which is the Rf gene product in BT-CMS rice. The amount of ORF79 protein in LD-CMS rice was one-twentieth of the amount in BT-CMS rice. The difference in ORF79 protein levels probably accounts for the mild and severe pollen defects in LD-CMS and BT-CMS rice, respectively. In the presence of Rf2, accumulation of ORF79 was reduced to almost zero and 25% in LD-CMS and BT-CMS rice, respectively, which probably accounts for the complete and weak fertility restoration abilities of Rf2 in LD-CMS and BT-CMS rice, respectively. These observations indicate that the amount of ORF79 influences the pollen fertility in two strains of rice in which CMS is induced by orf79. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  11. Intraspecific variation in mitochondrial genome sequence, structure, and gene content in Silene vulgaris, an angiosperm with pervasive cytoplasmic male sterility

    Czech Academy of Sciences Publication Activity Database

    Sloan, D.B.; Müller, Karel; McCauley, D.; Taylor, D.R.; Štorchová, Helena

    2012-01-01

    Roč. 196, č. 4 (2012), s. 1228-1239 ISSN 0028-646X R&D Projects: GA ČR GA521/09/0261; GA MŠk(CZ) LC06004; GA MŠk ME09035 Institutional research plan: CEZ:AV0Z50380511 Keywords : cytoplasmic male sterility (CMS) * gynodioecy * intracellular gene transfer Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.736, year: 2012

  12. Polymorphism in hybrid male sterility in wild-derived Mus musculus musculus strains on proximal chromosome 17

    Czech Academy of Sciences Publication Activity Database

    Vyskočilová, Martina; Pražanová, G.; Piálek, Jaroslav

    2009-01-01

    Roč. 20, č. 2 (2009), s. 83-91 ISSN 0938-8990 R&D Projects: GA MŠk LC06073; GA ČR GA206/06/0955 Institutional research plan: CEZ:AV0Z60930519 Keywords : hybrid male sterility * QTL mapping * polymorphism * Mus musculus musculus * Mus musculus domesticus Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.942, year: 2009

  13. Proteome analysis of the wild and YX-1 male sterile mutant anthers of wolfberry (Lycium barbarum L..

    Directory of Open Access Journals (Sweden)

    Rui Zheng

    Full Text Available Pollen development is disturbed in the early tetrad stage of the YX-1 male sterile mutant of wolfberry (Lycium barbarum L.. The present study aimed to identify differentially expressed anther proteins and to reveal their possible roles in pollen development and male sterility. To address this question, the proteomes of the wild-type (WT and YX-1 mutant were compared. Approximately 1760 protein spots on two-dimensional differential gel electrophoresis (2D-DIGE gels were detected. A number of proteins whose accumulation levels were altered in YX-1 compared with WT were identified by mass spectrometry and the NCBInr and Viridiplantae EST databases. Proteins down-regulated in YX-1 anthers include ascorbate peroxidase (APX, putative glutamine synthetase (GS, ATP synthase subunits, chalcone synthase (CHS, CHS-like, putative callose synthase catalytic subunit, cysteine protease, 5B protein, enoyl-ACP reductase, 14-3-3 protein and basic transcription factor 3 (BTF3. Meanwhile, activities of APX and GS, RNA expression levels of apx and atp synthase beta subunit were low in YX-1 anthers which correlated with the expression of male sterility. In addition, several carbohydrate metabolism-related and photosynthesis-related enzymes were also present at lower levels in the mutant anthers. In contrast, 26S proteasome regulatory subunits, cysteine protease inhibitor, putative S-phase Kinase association Protein 1(SKP1, and aspartic protease, were expressed at higher levels in YX-1 anthers relative to WT anthers. Regulation of wolfberry pollen development involves a complex network of differentially expressed genes. The present study lays the foundation for future investigations of gene function linked with wolfberry pollen development and male sterility.

  14. Development of transgenic lines from a male-sterile potato variety, with potential resistance to Tecia solanivora Povolny

    Directory of Open Access Journals (Sweden)

    Emy Shilena Torres

    2012-08-01

    Full Text Available Male sterility is a very important characteristic for environmental safety in genetically modified (GM plants, particularly in the release of transgenic plants in the centers of origin or high biodiversity areas. In order to contribute to the development of environmentally safe agricultural technologies that allow the proper use of transgenic potato crops in Colombia, this project developed transgenic potato cry1Ac of Bacillus thuringiensis (Bt, lines that are potentially resistant to T. solanivora, from the male-sterile variety Pastusa Suprema (PS (Solanum tuberosum ssp. andigena. Modifications were made to the Agrobacterium tumefaciens mediated-transformation protocol which allowed the genetic transformation of leaves of in vitro plants, with transformation efficiencies of 22 and 37%. Cry1Ac protein levels in transgenic leaves ranged from 88 to 639 ng mg-1 of fresh leaf tissue, suggesting a better potential plant resistance. This is the first report on transgenic lines with potential resistance to T. solanivora from a male-sterile variety of S. tuberosum ssp. andigena

  15. Organelle Simple Sequence Repeat Markers Help to Distinguish Carpelloid Stamen and Normal Cytoplasmic Male Sterile Sources in Broccoli

    Science.gov (United States)

    Shu, Jinshuai; Liu, Yumei; Li, Zhansheng; Zhang, Lili; Fang, Zhiyuan; Yang, Limei; Zhuang, Mu; Zhang, Yangyong; Lv, Honghao

    2015-01-01

    We previously discovered carpelloid stamens when breeding cytoplasmic male sterile lines in broccoli (Brassica oleracea var. italica). In this study, hybrids and multiple backcrosses were produced from different cytoplasmic male sterile carpelloid stamen sources and maintainer lines. Carpelloid stamens caused dysplasia of the flower structure and led to hooked or coiled siliques with poor seed setting, which were inherited in a maternal fashion. Using four distinct carpelloid stamens and twelve distinct normal stamens from cytoplasmic male sterile sources and one maintainer, we used 21 mitochondrial simple sequence repeat (mtSSR) primers and 32 chloroplast SSR primers to identify a mitochondrial marker, mtSSR2, that can differentiate between the cytoplasm of carpelloid and normal stamens. Thereafter, mtSSR2 was used to identify another 34 broccoli accessions, with an accuracy rate of 100%. Analysis of the polymorphic sequences revealed that the mtSSR2 open reading frame of carpelloid stamen sterile sources had a deletion of 51 bases (encoding 18 amino acids) compared with normal stamen materials. The open reading frame is located in the coding region of orf125 and orf108 of the mitochondrial genomes in Brassica crops and had the highest similarity with Raphanus sativus and Brassica carinata. The current study has not only identified a useful molecular marker to detect the cytoplasm of carpelloid stamens during broccoli breeding, but it also provides evidence that the mitochondrial genome is maternally inherited and provides a basis for studying the effect of the cytoplasm on flower organ development in plants. PMID:26407159

  16. 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

  17. 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

  18. Evaluation of the courtship and of the hybrid male sterility among Drosophila buzzatii cluster species (Diptera, Drosophilidae

    Directory of Open Access Journals (Sweden)

    MACHADO L. P. de B.

    2002-01-01

    Full Text Available In the Drosophila repleta group the establishment of subgroups and complexes made on the basis of morphological and cytological evidences is supported by tests of reproductive isolation. Among species in the repleta group, the buzzatii cluster, due to its polymorphism and polytipism, is an excellent material for ecological and speciation studies. Some interspecific crosses involving Drosophila seriema, Drosophila sp. B, D. koepferae and D. buzzatii strains were completely sterile while others involving strains from these species produced F1 hybrids that did not yield F2. In the present work, data on courtship duration and copula occurrence obtained in the analysis of flies from parental sterile crosses and on spermatozoon mobility observed in F1 hybrids that did not yield F2 are presented. Copula did not occur during one hour of observation and the spermatozoon also did not show mobility at any of the analyzed stages (3, 7, 9 and 10 days old. There was a high variation in courtship average duration and in the percentage of males that courted the females. The reproductive isolation mechanisms indicated by these observations were pre and post-zygotic, as supported by the absence of copula and male sterility. Data obtained also showed the occurrence of different degrees of reproductive compatibility among the strains classified as the same species but from distinct geographic localities.

  19. Individual and combined (Plus-hybrid effect of cytoplasmic male sterility and xenia on maize grain yield

    Directory of Open Access Journals (Sweden)

    Sofija Bozinovic

    2015-06-01

    Full Text Available Plus-hybrid effect refere to a combined effect of cytoplasmic male sterility (CMS and xenia in maize (Zea mays L. It could be used in commercial production by growing a mixture of 80% CMS hybrid and 20% of another fertile hybrid. The aim of this research was to examine individual and combined CMS and xenia effects on two hybrids widely grown in Serbia. Sterile and fertile versions of ZP 1 and ZP 2 hybrids (three-way; Iodent x Lancaster dents were used as females, while ZP 1, ZP 2, ZP 3, ZP 4, and ZP 5 (three-way or single cross; Iodent (BSSS x Lancaster dents were used as pollinators. All of them belong to medium maturity group. The trial was set up at one location in Serbia (Zemun Polje in 2009, 2010, and 2011. Molecular analysis of the five genotypes was done using simple sequence repeat (SSR primers. Plus-hybrid effect on grain yield ranged from -6.2% to 6.2%; on thousand kernel weight from -1.7% to 5.2%; on number of kernels per area from -1.0% to 8.0%. The poor response could be due to a use of three-way instead of single cross hybrids in S type of sterility. Modified Rogers' distance between hybrids was in the range 0.211 to 0.378 and was not relevant for the effect, which depended mostly on the sterile hybrid genotype and the fertile hybrid pollinator ability. This approach should be more suitable for female hybrids with slightly poorer performance, already being produced on a sterile base.

  20. Use of rhodamine B to mark the body and seminal fluid of male Aedes aegypti for mark-release-recapture experiments and estimating efficacy of sterile male releases.

    Directory of Open Access Journals (Sweden)

    Brian J Johnson

    2017-09-01

    Full Text Available Recent interest in male-based sterile insect technique (SIT and incompatible insect technique (IIT to control Aedes aegypti and Aedes albopictus populations has revealed the need for an economical, rapid diagnostic tool for determining dispersion and mating success of sterilized males in the wild. Previous reports from other insects indicated rhodamine B, a thiol-reactive fluorescent dye, administered via sugar-feeding can be used to stain the body tissue and seminal fluid of insects. Here, we report on the adaptation of this technique for male Ae. aegypti to allow for rapid assessment of competitiveness (mating success during field releases.Marking was achieved by feeding males on 0.1, 0.2, 0.4 or 0.8% rhodamine B (w/v in 50% honey solutions during free flight. All concentrations produced >95% transfer to females and successful body marking after 4 days of feeding, with 0.4 and 0.8% solutions producing the longest-lasting body marking. Importantly, rhodamine B marking had no effect on male mating competitiveness and proof-of-principle field releases demonstrated successful transfer of marked seminal fluid to females under field conditions and recapture of marked males.These results reveal rhodamine B to be a potentially useful evaluation method for male-based SIT/IIT control strategies as well as a viable body marking technique for male-based mark-release-recapture experiments without the negative side-effects of traditional marking methods. As a standalone method for use in mating competitiveness assays, rhodamine B marking is less expensive than PCR (e.g. paternity analysis and stable isotope semen labelling methods and less time-consuming than female fertility assays used to assess competitiveness of sterilised males.

  1. Use of rhodamine B to mark the body and seminal fluid of male Aedes aegypti for mark-release-recapture experiments and estimating efficacy of sterile male releases.

    Science.gov (United States)

    Johnson, Brian J; Mitchell, Sara N; Paton, Christopher J; Stevenson, Jessica; Staunton, Kyran M; Snoad, Nigel; Beebe, Nigel; White, Bradley J; Ritchie, Scott A

    2017-09-01

    Recent interest in male-based sterile insect technique (SIT) and incompatible insect technique (IIT) to control Aedes aegypti and Aedes albopictus populations has revealed the need for an economical, rapid diagnostic tool for determining dispersion and mating success of sterilized males in the wild. Previous reports from other insects indicated rhodamine B, a thiol-reactive fluorescent dye, administered via sugar-feeding can be used to stain the body tissue and seminal fluid of insects. Here, we report on the adaptation of this technique for male Ae. aegypti to allow for rapid assessment of competitiveness (mating success) during field releases. Marking was achieved by feeding males on 0.1, 0.2, 0.4 or 0.8% rhodamine B (w/v) in 50% honey solutions during free flight. All concentrations produced >95% transfer to females and successful body marking after 4 days of feeding, with 0.4 and 0.8% solutions producing the longest-lasting body marking. Importantly, rhodamine B marking had no effect on male mating competitiveness and proof-of-principle field releases demonstrated successful transfer of marked seminal fluid to females under field conditions and recapture of marked males. These results reveal rhodamine B to be a potentially useful evaluation method for male-based SIT/IIT control strategies as well as a viable body marking technique for male-based mark-release-recapture experiments without the negative side-effects of traditional marking methods. As a standalone method for use in mating competitiveness assays, rhodamine B marking is less expensive than PCR (e.g. paternity analysis) and stable isotope semen labelling methods and less time-consuming than female fertility assays used to assess competitiveness of sterilised males.

  2. DEVELOPMENT OF MELON F1 SEEDS BASED ON LINES WITH GENIC MALE STERILITY

    Directory of Open Access Journals (Sweden)

    A. S. Sokolov

    2014-01-01

    Full Text Available The perspective technology of development of melon of F1hybrids seeds by use maternal lines with an original form of genic mail sterility and marker trait (lobed leaves was studied. Elements of technology allow developing hybrid seeds of melon with hybridity of 90-95%.

  3. genetic analysis of male sterility genes in different a and b sorghum ...

    African Journals Online (AJOL)

    ACSS

    2018-02-06

    Feb 6, 2018 ... the generation of backcrossing from F1 to BC3, linear regression analysis was used following the formula of Hoshmand (2006): y = α + βx. Where: y = Proportion of sterility α = Intercept of the regression line β = Slope of the regression line x = Generation. Similarly, linear regression analysis was used.

  4. Transcriptomic Analysis of Differentially Expressed Genes during Flower Organ Development in Genetic Male Sterile and Male Fertile Tagetes erecta by Digital Gene-Expression Profiling.

    Directory of Open Access Journals (Sweden)

    Ye Ai

    Full Text Available Tagetes erecta is an important commercial plant of Asteraceae family. The male sterile (MS and male fertile (MF two-type lines of T. erecta have been utilized in F1 hybrid production for many years, but no report has been made to identify the genes that specify its male sterility that is caused by homeotic conversion of floral organs. In this study, transcriptome assembly and digital gene expression profiling were performed to generate expression profiles of MS and MF plants. A cDNA library was generated from an equal mixture of RNA isolated from MS and MF flower buds (1 mm and 4 mm in diameter. Totally, 87,473,431 clean tags were obtained and assembled into 128,937 transcripts among which 65,857 unigenes were identified with an average length of 1,188 bp. About 52% of unigenes (34,176 were annotated in Nr, Nt, Pfam, KOG/COG, Swiss-Prot, KO (KEGG Ortholog database and/or GO. Taking the above transcriptome as reference, 125 differentially expressed genes were detected in both developmental stages of MS and MF flower buds. MADS-box genes were presumed to be highly related to male sterility in T. erecta based on histological and cytological observations. Twelve MADS-box genes showed significantly different expression levels in flower buds 4 mm in diameter, whereas only one gene expressed significantly different in flower buds 1 mm in diameter between MS and MF plants. This is the first transcriptome analysis in T. erecta and will provide a valuable resource for future genomic studies, especially in flower organ development and/or differentiation.

  5. Exploration of miRNAs and target genes of cytoplasmic male sterility line in cotton during flower bud development.

    Science.gov (United States)

    Nie, Hushuai; Wang, Yumei; Su, Ying; Hua, Jinping

    2018-04-07

    Cytoplasmic male sterility (CMS) lines provide crucial material to harness heterosis for crop plants, which serves as an important strategy for hybrid seed production. However, the molecular mechanism remains obscure. Although microRNAs (miRNAs) play important roles in vegetative growth and reproductive growth, there are few reports on miRNAs regulating the development of male sterility in Upland cotton. In present study, 12 small RNA libraries were constructed and sequenced for two development stages of flower buds from a CMS line and its maintainer line. Based on the results, 256 novel miRNAs were allocated to 141 new miRNA families, and 77 known miRNAs belonging to 54 conserved miRNA families were identified as well. Comparative analysis revealed that 61 novel and 10 conserved miRNAs were differentially expressed. Further transcriptome analysis identified 232 target genes for these miRNAs, which participated in cellular developmental process, cell death, pollen germination, and sexual reproduction. In addition, expression patterns of typical miRNA and the negatively regulated target genes, such as PPR, ARF, AP2, and AFB, were verified by qRT-PCR in cotton flower buds. These targets were previously reported to be related to reproduction development and male sterility, suggesting that miRNAs might act as regulators of CMS occurrence. Some miRNAs displayed specific expression profiles in special developmental stages of CMS line and its fertile hybrid (F 1 ). Present study offers new information on miRNAs and their related target genes in exploiting CMS mechanism, and revealing the miRNA regulatory networks in Upland cotton.

  6. microRNAs involved in auxin signalling modulate male sterility under high-temperature stress in cotton (Gossypium hirsutum).

    Science.gov (United States)

    Ding, Yuanhao; Ma, Yizan; Liu, Nian; Xu, Jiao; Hu, Qin; Li, Yaoyao; Wu, Yuanlong; Xie, Sai; Zhu, Longfu; Min, Ling; Zhang, Xianlong

    2017-09-01

    Male sterility caused by long-term high-temperature (HT) stress occurs widely in crops. MicroRNAs (miRNAs), a class of endogenous non-coding small RNAs, play an important role in the plant response to various abiotic stresses. To dissect the working principle of miRNAs in male sterility under HT stress in cotton, a total of 112 known miRNAs, 270 novel miRNAs and 347 target genes were identified from anthers of HT-insensitive (84021) and HT-sensitive (H05) cotton cultivars under normal-temperature and HT conditions through small RNA and degradome sequencing. Quantitative reverse transcriptase-polymerase chain reaction and 5'-RNA ligase-mediated rapid amplification of cDNA ends experiments were used to validate the sequencing data. The results show that miR156 was suppressed by HT stress in both 84021 and H05; miR160 was suppressed in 84021 but induced in H05. Correspondingly, SPLs (target genes of miR156) were induced both in 84021 and H05; ARF10 and ARF17 (target genes of miR160) were induced in 84021 but suppressed in H05. Overexpressing miR160 increased cotton sensitivity to HT stress seen as anther indehiscence, associated with the suppression of ARF10 and ARF17 expression, thereby activating the auxin response that leads to anther indehiscence. Supporting this role for auxin, exogenous Indole-3-acetic acid (IAA) leads to a stronger male sterility phenotype both in 84021 and H05 under HT stress. Cotton plants overexpressing miR157 suppressed the auxin signal, and also showed enhanced sensitivity to HT stress, with microspore abortion and anther indehiscence. Thus, we propose that the auxin signal, mediated by miRNAs, is essential for cotton anther fertility under HT stress. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  7. Clinical Evaluation of Non-surgical Sterilization of Male Cats with Single Intra-testicular Injection of Calcium Chloride

    Directory of Open Access Journals (Sweden)

    Samanta Prabhat K

    2011-07-01

    Full Text Available Abstract Background Calcium chloride solution is an established injectable sterilant in dogs and other mammals. With cat populations a continuing problem, we sought to explore its first use in cats. Six cats per group were injected with 5%, 10% or 20% calcium chloride dihydrate in saline solution with lignocaine hydrochloride, a local anaesthetic. Results At the 60th day post-injection, cat testes were collected and showed complete testicular necrosis and replacement by fibrous tissue; very low sperm counts; and reduction of serum testosterone by at least 70% in 20% dose. Androgenic enzyme activities and their expressions were also reduced in all the treated groups along with intra-testicular testosterone concentration was also low. Increased testicular lipid peroxidation, with reduced antioxidants and mitochondrial membrane potential, were evident following calcium chloride treatments. However, there were no apparent changes in serum concentrations of cortisol, fasting blood sugar level, blood urea nitrogen, packed cell volume, or total serum protein following calcium chloride injection, suggesting that this method of sterilization is not associated with any general stress response. Conclusion Calcium chloride solution demonstrates potential for androgenesis-eliminating nonsurgical sterilization of male cats in addition to its proven efficacy in dogs and other mammals.

  8. Recombination Events Involving the atp9 Gene Are Associated with Male Sterility of CMS PET2 in Sunflower

    Directory of Open Access Journals (Sweden)

    Antje Reddemann

    2018-03-01

    Full Text Available Cytoplasmic male sterility (CMS systems represent ideal mutants to study the role of mitochondria in pollen development. In sunflower, CMS PET2 also has the potential to become an alternative CMS source for commercial sunflower hybrid breeding. CMS PET2 originates from an interspecific cross of H. petiolaris and H. annuus as CMS PET1, but results in a different CMS mechanism. Southern analyses revealed differences for atp6, atp9 and cob between CMS PET2, CMS PET1 and the male-fertile line HA89. A second identical copy of atp6 was present on an additional CMS PET2-specific fragment. In addition, the atp9 gene was duplicated. However, this duplication was followed by an insertion of 271 bp of unknown origin in the 5′ coding region of the atp9 gene in CMS PET2, which led to the creation of two unique open reading frames orf288 and orf231. The first 53 bp of orf288 are identical to the 5′ end of atp9. Orf231 consists apart from the first 3 bp, being part of the 271-bp-insertion, of the last 228 bp of atp9. These CMS PET2-specific orfs are co-transcribed. All 11 editing sites of the atp9 gene present in orf231 are fully edited. The anther-specific reduction of the co-transcript in fertility-restored hybrids supports the involvement in male-sterility based on CMS PET2.

  9. 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

  10. The effects of cytoplasmic male sterility and xenia on the chemical composition of maize grain

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    Vančetović Jelena

    2009-01-01

    Full Text Available Sterile hybrids often outyield their fertile counterparts, especially if pollinated by a genetically unrelated pollinator. The combined effect of cms and xenia is referred to as the Plus-hybrid effect. The objective of this study was to determine the individual, as well as, combining effect of cms and xenia on the maize grain chemical composition. The percent of oil, protein and starch in the grain was also observed. Two sterile hybrids, their fertile counterparts and five fertile pollinator-hybrids were selected for the studies. The three-replicate trial set up according to the split-plot experimental design was performed at Zemun Polje in 2008. The obtained results show that the effects of cms on the oil percent was not significant in the studied hybrid ZP 341, while it increased at the significance level of P = 0.1 in the second observed hybrid ZP 360. The effect of this factor on the protein and starch percent was also significant (P = 0.01 in some hybrid combinations. Xenia effects on all three chemical parameters were significant (P = 0.01 in some hybrid combinations. The gained results indicate that the identification of a good combination of two hybrids, in which one would be a sterile female component, and the other a pollinator, would end up not only in the increased yield, but also in the improved maize grain quality.

  11. Identification and Functional Analysis of microRNAs Involved in the Anther Development in Cotton Genic Male Sterile Line Yu98-8A

    Directory of Open Access Journals (Sweden)

    Xiaojie Yang

    2016-10-01

    Full Text Available Hybrid vigor contributes in a large way to the yield and quality of cotton (Gossypium hirsutum fiber. Although microRNAs play essential regulatory roles in flower induction and development, it is still unclear if microRNAs are involved in male sterility, as the regulatory molecular mechanisms of male sterility in cotton need to be better defined. In this study, two independent small RNA libraries were constructed and sequenced from the young buds collected from the sporogenous cell formation to the meiosis stage of the male sterile line Yu98-8A and the near-isogenic line. Sequencing revealed 1588 and 1536 known microRNAs and 347 and 351 novel miRNAs from male sterile and male fertile libraries, respectively. MicroRNA expression profiles revealed that 49 conserved and 51 novel miRNAs were differentially expressed. Bioinformatic and degradome analysis indicated the regulatory complexity of microRNAs during flower induction and development. Further RT-qPCR and physiological analysis indicated that, among the different Kyoto Encyclopedia Gene and Genomes pathways, indole-3-acetic acid and gibberellic acid signaling transduction pathways may play pivotal regulatory functions in male sterility.

  12. Characterization of cytoplasmic male sterility of rice with Lead Rice cytoplasm in comparison with that with Chinsurah Boro II cytoplasm.

    Science.gov (United States)

    Itabashi, Etsuko; Kazama, Tomohiko; Toriyama, Kinya

    2009-02-01

    Rice with LD-type cytoplasmic male sterility (CMS) possesses the cytoplasm of 'Lead Rice' and its fertility is recovered by a nuclear fertility restorer gene Rf1. Rf1 promotes processing of a CMS-associated mitochondrial RNA of atp6-orf79, which consists of atp6 and orf79, in BT-CMS with the cytoplasm of 'Chinsurah Boro II'. In this study, we found that LD-cytoplasm contained a sequence variant of orf79 downstream of atp6. Northern blot analysis showed that atp6-orf79 RNA of LD-cytoplasm was co-transcribed and was processed in the presence of Rf1 in the same manner as in BT-cytoplasm. Western blot analysis showed that the ORF79 peptide did not accumulate in an LD-CMS line, while ORF79 accumulated in a BT-CMS line and was diminished by Rf1. These results suggest that accumulation of ORF79 is not the cause of CMS in LD-cytoplasm and the mechanism of male-sterility induction/fertility restoration in LD-CMS is different from that in BT-CMS.

  13. 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)

  14. Re-engineering the zinc fingers of PRDM9 reverses hybrid sterility in mice.

    Science.gov (United States)

    Davies, Benjamin; Hatton, Edouard; Altemose, Nicolas; Hussin, Julie G; Pratto, Florencia; Zhang, Gang; Hinch, Anjali Gupta; Moralli, Daniela; Biggs, Daniel; Diaz, Rebeca; Preece, Chris; Li, Ran; Bitoun, Emmanuelle; Brick, Kevin; Green, Catherine M; Camerini-Otero, R Daniel; Myers, Simon R; Donnelly, Peter

    2016-02-11

    The DNA-binding protein PRDM9 directs positioning of the double-strand breaks (DSBs) that initiate meiotic recombination in mice and humans. Prdm9 is the only mammalian speciation gene yet identified and is responsible for sterility phenotypes in male hybrids of certain mouse subspecies. To investigate PRDM9 binding and its role in fertility and meiotic recombination, we humanized the DNA-binding domain of PRDM9 in C57BL/6 mice. This change repositions DSB hotspots and completely restores fertility in male hybrids. Here we show that alteration of one Prdm9 allele impacts the behaviour of DSBs controlled by the other allele at chromosome-wide scales. These effects correlate strongly with the degree to which each PRDM9 variant binds both homologues at the DSB sites it controls. Furthermore, higher genome-wide levels of such 'symmetric' PRDM9 binding associate with increasing fertility measures, and comparisons of individual hotspots suggest binding symmetry plays a downstream role in the recombination process. These findings reveal that subspecies-specific degradation of PRDM9 binding sites by meiotic drive, which steadily increases asymmetric PRDM9 binding, has impacts beyond simply changing hotspot positions, and strongly support a direct involvement in hybrid infertility. Because such meiotic drive occurs across mammals, PRDM9 may play a wider, yet transient, role in the early stages of speciation.

  15. Mating competitiveness of male Anopheles arabiensis mosquitoes irradiated with a partially or fully sterilizing dose in small and large laboratory cages

    NARCIS (Netherlands)

    Helinski, M.; Knols, B.G.J.

    2008-01-01

    Male mating competitiveness is a crucial parameter in many genetic control programs including the sterile insect technique (SIT). We evaluated competitiveness of male Anopheles arabiensis Patton as a function of three experimental variables: (1) small or large cages for mating, (2) the effects of

  16. Study of effect of radiation on the parameters of quality of sterile males of Ceratitis Ceratitis capitata (Wied.) and their improvement aroma therapy

    International Nuclear Information System (INIS)

    Nouira, Manel

    2008-01-01

    In this present work, we are interested in studying the various stages in the production of sterile males, the effect of different doses of irradiation on longevity, compatibility and competitiveness of these males. And the effect of exposure of adults and pupae of Ceratitis to different doses of essential oil of ginger on their compatibility and competitiveness. (Author)

  17. iTRAQ-facilitated proteomic profiling of anthers from a photosensitive male sterile mutant and wild-type cotton (Gossypium hirsutum L.).

    Science.gov (United States)

    Liu, Ji; Pang, Chaoyou; Wei, Hengling; Song, Meizhen; Meng, Yanyan; Ma, Jianhui; Fan, Shuli; Yu, Shuxun

    2015-08-03

    Male sterility is a common phenomenon in flowering plants, and it has been successfully developed in several crops by taking advantage of heterosis. Cotton (Gossypium hirsutum L.) is an important economic crop, used mainly for the production of textile fiber. Using a space mutation breeding technique, a novel photosensitive genetic male sterile mutant CCRI9106 was isolated from the wild-type upland cotton cultivar CCRI040029. To use CCRI9106 in cotton hybrid breeding, it is of great importance to study the molecular mechanisms of its male sterility. Here, histological and iTRAQ-facilitated proteomic analyses of anthers were performed to explore male sterility mechanisms of the mutant. Scanning and transmission electron microscopy of the anthers showed that the development of pollen wall in CCRI9106 was severely defective with a lack of exine formation. At the protein level, 6121 high-confidence proteins were identified and 325 of them showed differential expression patterns between mutant and wild-type anthers. The proteins up- or down-regulated in MT anthers were mainly involved in exine formation, protein degradation, calcium ion binding,etc. These findings provide valuable information on the proteins involved in anther and pollen development, and contribute to elucidate the mechanism of male sterility in upland cotton. Copyright © 2015. Published by Elsevier B.V.

  18. Sterilization of male house mosquitoes, culex pipiens fatigans by means of low doses of gamma rays

    Energy Technology Data Exchange (ETDEWEB)

    Danusupadmo, C.J.; Sugiarto (National Atomic Energy Agency, Jakarta (Indonesia). Pasar Djumat Research Centre)

    1981-07-01

    The experiment of mating efficiency of normal and gamma irradiated male population of Medan (M), Jakarta (J) and Kupang (K) was calculated when they were mated to their respective normal females or to females of different populations. The criterion used was the degree of failure in the egg-hatch. As males, irradiated M, when mated to normal females of M, K, and J, showed comparable results in their LD/sub 50/ and LD/sub 100/ values, which indicated that there were no differences in the responses of M, K, and J normal females to irradiated M males. Matings between irradiated males of K and J and their respective normal females compared to that between irradiated M males and K and J females (KK vs MK, JJ vs MJ) revealed, viewed from their respective LD/sub 50/ and LD/sub 100/ values, that M and J males were inferior to K males. Complete failure of egg-hatch was achieved at radiation doses between 9 and 10 krad, while 50 percent egg-hatch took place at doses of 5 krad and slightly below.

  19. Comprehensive analysis of genic male sterility-related genes in Brassica rapa using a newly developed Br300K oligomeric chip.

    Directory of Open Access Journals (Sweden)

    Xiangshu Dong

    Full Text Available To identify genes associated with genic male sterility (GMS that could be useful for hybrid breeding in Chinese cabbage (Brassicarapa ssp. pekinensis, floral bud transcriptome analysis was carried out using a B. rapa microarray with 300,000 probes (Br300K. Among 47,548 clones deposited on a Br300K microarray with seven probes of 60 nt length within the 3' 150 bp region, a total of 10,622 genes were differentially expressed between fertile and sterile floral buds; 4,774 and 5,848 genes were up-regulated over 2-fold in fertile and sterile buds, respectively. However, the expression of 1,413 and 199 genes showed fertile and sterile bud-specific features, respectively. Genes expressed specifically in fertile buds, possibly GMS-related genes, included homologs of several Arabidopsis male sterility-related genes, genes associated with the cell wall and synthesis of its surface proteins, pollen wall and coat components, signaling components, and nutrient supplies. However, most early genes for pollen development, genes for primexine and callose formation, and genes for pollen maturation and anther dehiscence showed no difference in expression between fertile and sterile buds. Some of the known genes associated with Arabidopsis pollen development showed similar expression patterns to those seen in this study, while others did not. BrbHLH89 and BrMYP99 are putative GMS genes. Additionally, 17 novel genes identified only in B. rapa were specifically and highly expressed only in fertile buds, implying the possible involvement in male fertility. All data suggest that Chinese cabbage GMS might be controlled by genes acting in post-meiotic tapetal development that are different from those known to be associated with Arabidopsis male sterility.

  20. Sequencing and annotation of the chloroplast DNAs and identification of polymorphisms distinguishing normal male-fertile and male-sterile cytoplasms of onion.

    Science.gov (United States)

    von Kohn, Christopher; Kiełkowska, Agnieszka; Havey, Michael J

    2013-12-01

    Male-sterile (S) cytoplasm of onion is an alien cytoplasm introgressed into onion in antiquity and is widely used for hybrid seed production. Owing to the biennial generation time of onion, classical crossing takes at least 4 years to classify cytoplasms as S or normal (N) male-fertile. Molecular markers in the organellar DNAs that distinguish N and S cytoplasms are useful to reduce the time required to classify onion cytoplasms. In this research, we completed next-generation sequencing of the chloroplast DNAs of N- and S-cytoplasmic onions; we assembled and annotated the genomes in addition to identifying polymorphisms that distinguish these cytoplasms. The sizes (153 538 and 153 355 base pairs) and GC contents (36.8%) were very similar for the chloroplast DNAs of N and S cytoplasms, respectively, as expected given their close phylogenetic relationship. The size difference was primarily due to small indels in intergenic regions and a deletion in the accD gene of N-cytoplasmic onion. The structures of the onion chloroplast DNAs were similar to those of most land plants with large and small single copy regions separated by inverted repeats. Twenty-eight single nucleotide polymorphisms, two polymorphic restriction-enzyme sites, and one indel distributed across 20 chloroplast genes in the large and small single copy regions were selected and validated using diverse onion populations previously classified as N or S cytoplasmic using restriction fragment length polymorphisms. Although cytoplasmic male sterility is likely associated with the mitochondrial DNA, maternal transmission of the mitochondrial and chloroplast DNAs allows for polymorphisms in either genome to be useful for classifying onion cytoplasms to aid the development of hybrid onion cultivars.

  1. Mating competitiveness of male Anopheles arabiensis mosquitoes irradiated with a partially or fully sterilizing dose in small and large laboratory cages.

    Science.gov (United States)

    Helinski, M E H; Knols, B G J

    2008-07-01

    Male mating competitiveness is a crucial parameter in many genetic control programs including the sterile insect technique (SIT). We evaluated competitiveness of male Anopheles arabiensis Patton as a function of three experimental variables: (1) small or large cages for mating, (2) the effects of either a partially sterilizing (70 Gy) or fully sterilizing (120 Gy) dose, and (3) pupal or adult irradiation. Irradiated males competed for females with an equal number of unirradiated males. Competitiveness was determined by measuring hatch rates of individually laid egg batches. In small cages, pupal irradiation with the high dose resulted in the lowest competitiveness, whereas adult irradiation with the low dose gave the highest, with the latter males being equal in competitiveness to unirradiated males. In the large cage, reduced competitiveness of males irradiated in the pupal stage was more pronounced compared with the small cage; the males irradiated as adults at both doses performed similarly to unirradiated males. Unexpectedly, males irradiated with the high dose performed better in a large cage than in a small one. A high proportion of intermediate hatch rates was observed for eggs collected in the large cage experiments with males irradiated at the pupal stage. It is concluded that irradiation of adult An. arabiensis with the partially sterilizing dose results in the highest competitiveness for both cage designs. Cage size affected competitiveness for some treatments; therefore, competitiveness determined in laboratory experiments must be confirmed by releases into simulated field conditions. The protocols described are readily transferable to evaluate male competitiveness for other genetic control techniques.

  2. Microarray analysis reveals altered expression of a large number of nuclear genes in developing cytoplasmic male sterile Brassica napus flowers.

    Science.gov (United States)

    Carlsson, Jenny; Lagercrantz, Ulf; Sundström, Jens; Teixeira, Rita; Wellmer, Frank; Meyerowitz, Elliot M; Glimelius, Kristina

    2007-02-01

    To gain new insights into the mechanism underlying cytoplasmic male sterility (CMS), we compared the nuclear gene expression profiles of flowers of a Brassica napus CMS line with that of the fertile B. napus maintainer line using Arabidopsis thaliana flower-specific cDNA microarrays. The CMS line used has a B. napus nuclear genome, but has a rearranged mitochondrial (mt) genome consisting of both B. napus and A. thaliana DNA. Gene expression profiling revealed that a large number of genes differed in expression between the two lines. For example, nuclear genes coding for proteins that are involved in protein import into organelles, genes expressed in stamens and pollen, as well as genes implicated in either cell-wall remodeling or architecture, were repressed in the CMS line compared with B. napus. These results show that the mt genome of the CMS line strongly influences nuclear gene expression, and thus reveal the importance of retrograde signalling between the mitochondria and the nucleus. Furthermore, flowers of the CMS line are characterized by a replacement of stamens with carpelloid organs, and thus partially resemble the APETALA3 (AP3) and PISTILLATA (PI) mutants. In accordance with this phenotype, AP3 expression was downregulated in the stamens, shortly before these organs developed carpelloid characteristics, even though it was initiated correctly. Repression of PI succeeded that of AP3 and might be a consequence of a loss of AP3 activity. These results suggest that AP3 expression in stamens depends on proper mt function and a correct nuclear-mt interaction, and that mt alterations cause the male sterility phenotype of the CMS line.

  3. Effect of rearing diet on the infection rate in flies released for the control of tsetse populations by sterile males

    International Nuclear Information System (INIS)

    Maudlin, I.

    1990-01-01

    In areas where sleeping sickness is endemic, it is the practice of sterile insect technique (SIT) programmes to give sterilized males a bloodmeal before release into the wild in order to reduce the risk of these released flies acting as disease vectors. This strategy has been adopted because of experimental evidence which showed that it was essential to infect flies at their first feed to establish a Tripanosoma brucei gambiense or T. b rhodesiense infection in tsetse flies. The aim of the work was to test artificial tsetse diets produced in the IAEA Laboratory at Seibersdorf in order to determine whether they were as effective as whole blood in inhibiting T. brucei sensu lato (sl) infections in flies. Seven artificial diets were tested with T.b. rhodesiense; Glossina morsitans morsitans males were fed one meal of the diet and then starved for 3 days before the infective feed. None of these diets significantly altered the infection rate of the treated flies and the seven groups produced statistically homogeneous results, with a mean midgut rate of 16% (control flies fed pig blood: 17%). Flies infected as tenerals with the same trypanosome stock produced midgut rates of 61%. Three of the diets were also tested with a T. congolense stock. There were no significant differences between flies fed artificial (mean midgut infection rate: 15%) and whole blood diets (19%). G. m. morsitans infected as tenerals with this trypanosome stock produced midgut rates of 66%. As with T. brucei sl infections, teneral flies were far more likely to develop a T. congolense infection than fed flies; this result suggests that all the tsetse flies used in SIT programmes should be fed before release in order to reduce the risk both to man and his livestock. Artificial diets are as effective as whole blood in inhibiting trypanosome infections. The effect of bloodmeal on the fly infection rates is discussed in relation to lectin production in fed flies. (author). 13 refs, 2 tabs

  4. Cytogenetics of Triatominae: III - A study on male sterility induced through hybridization of Triatoma sórdida and Triatoma pseudomaculata

    Directory of Open Access Journals (Sweden)

    Giorgio Schreiber

    1975-08-01

    Full Text Available Males from bilateral crosses between Triatoma sórdida and Triatoma pseudomaculata were unable to give offspring, as shown by subsequent backcrosses (BC between hybrid males and parental females. This kind of sterility indueed through interspecific hybridization seems to be due to lack of sperm migration from the bursa copulatrix to the spermateca, thus suggesting primarily failure on the part of hybrid males to produce and/or to incorporate male accessory secretions into the spermatophore bulb. Addicional proof that sterility induced in hybrid males is at the sperm level has been afforded by the spermatogenesis herein studied. The anomalous processes like; 1 prophases of spermatogonia with the chromosomes scattered in the cytoplasm, 2 first metaphases with unpaired tetrades, 3 spermatids differing in size and 4 spermatozoa of abnormal shape and generdlly of giant size, can be taken as an indicator of the degree of departure from the normal course of spermatogenesis.

  5. Male sterility associated with overexpression of the noncoding hsrω ...

    Indian Academy of Sciences (India)

    A complete excision of the P transposon insertion restored male fertility as well as the fine-speckled pattern of omega speckles in the cyst cells. The in situ distribution patterns of ... The consequent limiting availability of hnRNPs is likely to trans-dominantly affect processing of other pre-mRNAs in cyst cells. We suggest that a ...

  6. [Study on psychiatric disorders and defensive process assessed by the "defense style questionnaire" in sterile males SAMPLE consulting in andrology].

    Science.gov (United States)

    Bellone, M; Cottencin, O; Rigot, J M; Goudemand, M

    2005-01-01

    The literature about artificial insemination and the associated psychological, psychiatric and sexual disorders is relatively rich. But the majority of these studies is made in gynaecology, with a feminine approach of the disorder. There are very few works led in andrology. This justified the investigation of new trails in order to understand better the clinical context of the sterile man. We undertake a study about the psychiatric disorders among sterile men and about the defense styles. These are a clinical entity recently introduced in the quantitative psychopathology research. The defense style questionnaire (DSQ) is a psychometric scale used in common practice in order to measure the defense styles. We made this study in order to examine the psychiatric state of a sterile males sample consulting in andrology; to assess the defense style by means of the Bond and al DSQ-88 ; to look into a difference between the defensive process according to their clinical situation of azoospermic males or as the oligoazoospermic males and finally, to reveal a correlation between the psychiatric disorders developed in this sample of sterile males and the defensive process they used. There were 42 people (22 azoospermic males and 20 oligoazoospermic males) aged between 23 and 49 years old in the analysed sample. These have been selected at the surgery of andrology at the RUHC of Lille, depending on their arrival order for 6 months. There was no significant difference between the two groups as far as the age and the education standard are concerned. The selection criteria were medical and somatic. Our sample population were divided into two groups: azoospermia (no spermatozoon found in the semen analysis) and oligoasthenospermia (decrease of the number and the mobility of the spermatozoa and an increase of the percentage of atypical forms). The method first consisted in the DSQ, followed by the analysis of the psychiatric state according to the DSM IV, a hetero questionnaire to

  7. Possibilities of eradicating the codling moth, Cydia pomonella L. from Syria, by releasing gamma irradiation sterilized males

    International Nuclear Information System (INIS)

    Mansour, M.

    1994-01-01

    Being a large apple producer, Syria is facing difficulties in exporting its surplus because of the high level of pesticide residues from the control of Codling moth, Cydia pomonella L. etc. In addition, these species are under quarantine in some countries. A solution could be in using the sterile insect release technique (SIRT) for Codling moth. This method, however, has some limitations. It requires a thorough knowledge of biology and ecology of the pest species. It is also specific and effective towards particular pest species. A disadvantage could be the necessity to spray for other apple pests. Reporting the life history of the Codling moth in the apple producing regions, this paper discusses the possibility of using the SIRT for codling moth eradication. The results of the study indicate that the Codling moth has two distinct generations in the three main producing regions of the country. They also show that the separation between generations is very clear which may facilitate decision making in Codling moth control and eradication methods and reduces the number of required pesticide sprays. This also could be useful in adjusting Codling moth mass reading and release operations in a sterile insect release programme. Sex ratio is about 1:1 (males to females) and fecundity of the summer generation is higher than the spring one. The results also show that a very small percentage of the spring generation larvae enter diapause, while most of the summer generation larvae and all of those maturing in September do so. Studies on population density show that it is more than 5 times higher in neglected orchards than in commercial ones. Also the Codling moth summer generation increases about three times more than the spring generation, due probably to higher fecundity and favourable climatic conditions. (author)

  8. Effects of rootstocks on cryotolerance and overwintering survivorship of genic male sterile lines in upland cotton (Gossypium hirsutum L..

    Directory of Open Access Journals (Sweden)

    Xin Zhang

    Full Text Available Grafting desirable scion on stress-tolerant rootstocks provides an opportunity to improve the cryotolerance of scion. Genic male sterile (GMS lines of plant could be used as sterile line and maintainer in breeding, and they have the conspicuous characteristics that the fertility of which is easy to regain but hard to maintain by sexual reproduction. In order to maintain the fertility of GMS cotton by means of its perennial growth on the basis of frostless winters in Nanning, Guangxi autonomous region, GMS line A4 was grafted onto 7 cryotolerant rootstocks (F118, F697, F098, F112, F113, P098 and P113, and the cryotolerance and the overwintering survivorship of scions were investigated. In consequence, when compared with control (self-grafted A4, the relative conductivity of the grafted plants in shoot bark was reduced (8.80%, the content of soluble sugar, soluble protein and free proline were higher, 25.00, 1.55, 3.46%, respectively; the overwintering survival rate and the height of regeneration bud under field condition of grafted plants were higher, 10.44, 15.75%, respectively; the order of the grafted plants based on the average subordinate function value of overwintering survivorship was A4/F113>A4/F118>A4/F098>A4/F697>A4/F112>A4/P098>A4/P113>A4/A4(CK; the correlation analyses indicated that the physiological parameters of cryotolerance could be used for forecasting the overwintering survivorship, and the relative conductivity could be chosen as the first physiological parameter for forecasting cryotolerance or overwintering survivorship. The results indicate that the cryotolerance and the overwintering survivorship of GMS cotton could be improved by grafting, and F113 appeared to be a valuable rootstock.

  9. Comparative Analysis of Genome Wide DNA Methylation Profiles for the Genic Male Sterile Cabbage Line 01-20S and Its Maintainer Line

    Science.gov (United States)

    Han, Fengqing; Zhang, Xiaoli; Liu, Xing; Su, Henan; Kong, Congcong; Fang, Zhiyuan; Yang, Limei; Zhuang, Mu; Zhang, Yangyong; Liu, Yumei; Li, Zhansheng; Lv, Honghao

    2017-01-01

    Methylation modifications play an important role in multiple biological processes. Several studies have reported altered methylation patterns in male sterile plants such as rice and wheat, but little is known about the global methylation profiles and their possible roles in the cabbage (Brassica oleracea) male sterile line. In this study, single-base-resolution bisulfite sequencing (BS-Seq) was adopted to identify the pattern and degree of cytosine methylation in the male sterile line 01-20S and its near-isogenic fertile line 01-20F. Similar methylation patterns were profiled, with some changes observed in local positions. In total, 505 differentially methylated genomic regions (DMRs) and 106 DMR-associated genes were detected. Nine genes related to pollen development were discovered and further validated by a quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Among these, four were downregulated in 01-20S. In particular, Bol039180 (an invertase/pectin methylesterase inhibitor family protein) is likely involved in pectin degradation, and might play an important role in the pollen separation defects of 01-20S. This study facilitates a better understanding of DNA methylation alterations and their possible roles in genic male sterility in cabbages. PMID:28621722

  10. Molecular Mapping of D1, D2 and ms5 Revealed Linkage between the Cotyledon Color Locus D2 and the Male-Sterile Locus ms5 in Soybean

    Directory of Open Access Journals (Sweden)

    Alina Ott

    2013-07-01

    Full Text Available In soybean, genic male sterility can be utilized as a tool to develop hybrid seed. Several male-sterile, female-fertile mutants have been identified in soybean. The male-sterile, female-fertile ms5 mutant was selected after fast neutron irradiation. Male-sterility due to ms5 was associated with the “stay-green” cotyledon color mutation. The cotyledon color trait in soybean is controlled by two loci, D1 and D2. Association between cotyledon color and male-sterility can be instrumental in early phenotypic selection of sterility for hybrid seed production. The use of such selection methods saves time, money, and space, as fewer seeds need to be planted and screened for sterility. The objectives of this study were to compare anther development between male-fertile and male-sterile plants, to investigate the possible linkages among the Ms5, D1 and D2 loci, and to determine if any of the d1 or d2 mutations can be applied in hybrid seed production. The cytological analysis during anther development displayed optically clear, disintegrating microspores and enlarged, engorged pollen in the male-sterile, female-fertile ms5ms5 plants, a common characteristic of male-sterile mutants. The D1 locus was mapped to molecular linkage group (MLG D1a and was flanked by Satt408 and BARCSOYSSR_01_1622. The ms5 and D2 loci were mapped to MLG B1 with a genetic distance ~12.8 cM between them. These results suggest that use of the d2 mutant in the selection of male-sterile line may attenuate the cost hybrid seed production in soybean.

  11. Sterilization: A Review and Update.

    Science.gov (United States)

    Moss, Chailee; Isley, Michelle M

    2015-12-01

    Sterilization is a frequently used method of contraception. Female sterilization is performed 3 times more frequently than male sterilization, and it can be performed immediately postpartum or as an interval procedure. Methods include mechanical occlusion, coagulation, or tubal excision. Female sterilization can be performed using an abdominal approach, or via laparoscopy or hysteroscopy. When an abdominal approach or laparoscopy is used, sterilization occurs immediately. When hysteroscopy is used, tubal occlusion occurs over time, and additional testing is needed to confirm tubal occlusion. Comprehensive counseling about sterilization should include discussion about male sterilization (vasectomy) and long-acting reversible contraceptive methods. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Produção de sementes macho-estéreis em arroz Male-sterile rice seed production

    Directory of Open Access Journals (Sweden)

    Claudio Bragantini

    2001-02-01

    Full Text Available A obtenção comercial de sementes da linhagem macho-estéril é uma das limitações para viabilizar a produção de híbridos de arroz (Oryza sativa L.. Este trabalho buscou estudar três proporções entre a linhagem macho-estéril (linhagem A e a mantenedora (linhagem B. As proporções estudadas foram 8:4, 10:2 e 14:4. As características avaliadas para determinar qual das proporções apresenta maior potencial foram: número e porcentagem de grãos cheios por panículas, e número de grãos de pólen por unidade de área. A proporção 8:4 produziu maior porcentagem de grãos cheios por panícula que as outras duas, mas, proporcionalmente, ocupa maior área física com a linhagem B no campo. Foram observadas diferenças estatísticas na porcentagem de grãos cheios entre as amostras coletadas nas várias fileiras da linhagem A (diferentes distâncias da fonte polinizadora, e observou-se uma influência marcante com relação à direção predominante dos ventos. O número de grãos de pólen foi igual para todas as relações e distâncias da fonte de pólen; por isso, não foi o fator determinante das diferenças observadas em porcentagem de grãos cheios por panícula. Os resultados permitiram concluir que a proporção 10:2 é a de maior potencial para a produção comercial de sementes da linhagem macho-estéril.Commercial male-sterile rice (Oryza sativa L. seed production is one of the limitations to allow large scale hybrid seed production. This work studied three ratios between male-sterile line (A line and maintainer (B line. The A:B ratios used in the study were: 8:4, 10:2 and 14:4. The evaluated traits to determine which ratio is more suitable were: number and percentage of filled grains per panicle and number of pollen grains per unit area. The 8:4 ratio produced statistically significant higher percentage of filled grains per panicle than the other two, but proportionally it requires more field area for the B line. Statistical

  13. [Male sterility and its association with genital disease and environmental factors].

    Science.gov (United States)

    Merino Ruiz, M C; De León Cervantes, M G; García Flores, R F

    1995-10-01

    Semen quality may be affected by many factors, as there is evidence that conditions as varicocele, criptorquidia, orchitis and bacterian infections; as well as to exposure to physical agents as heat, or chemical substances, or ingestion of alcohol and drugs, may affect semen quality. The objective of this study is to investigate the risk implied in the exposure to these factors on the semen quality. The study was carried out in a prospective way in a group of males at Clínica de Infertilidad, Unidad de Biología de la Reproducción del Hospital Universitario Dr. J.E. González. Ninety nine males were studied, they received an intentioned questionnaire about antecedents of exposure to environmental factors, and urologic resolved pathology. Espermatobioscopy was done and it was classified according to OMS. Two groups were formed, one with the individuals with normal espermatobioscopy (n = 25); and the abnormal ones (n = 74). The statistical Incidences Reason, square Xi and Atributable Risk, were applied in order to determine the impact that different factors may have on semen quality. The found alterations in semen were astenozoospermia (n = 58); hypospermia (n = 22); oligozoospermia (n = 18); teratozoospermia (n = 7); polizoospermia (n = 7); and azoospermia (n = 6). The results of the mentioned statistical tests, show that in these alterations there is an associated risk factor to the use of tobacco, exposure to chemical substances, to physical aggresors; and anatomic anomalies previously corrected. It is considered that obtention of this information is a great help because once the unfavorable factors are eliminated, the environment is improved in order to obtain an espermatogenesis in optimal conditions.

  14. Comparative Transcriptome Profile of the Cytoplasmic Male Sterile and Fertile Floral Buds of Radish (Raphanus sativus L.

    Directory of Open Access Journals (Sweden)

    Shiyong Mei

    2016-01-01

    Full Text Available Radish cytoplasmic male sterility (CMS has been widely used for breeding in Raphanus and Brassica genera. However, the detailed regulation network of the male sterility remains to be determined. Our previous work has shown that the abnormalities in a CMS radish appeared shortly after the tetrad stage when microspores were malformed and the tapetal cells grew abnormally large. In this work, histological analysis shows that anthers are at the tetrad stage when the radish buds are about 1.5 mm in length. Furthermore, a high throughput RNA sequencing technology was employed to characterize the transcriptome of radish buds with length about 1.5 mm from two CMS lines possessing the CMS-inducing orf138 gene and corresponding near-isogenic maintainer lines. A total of 67,140 unigenes were functionally annotated. Functional terms for these genes are significantly enriched in 55 Gene Ontology (GO groups and 323 Kyoto Encyclopedia of Genes and Genomes (KEGG pathways. The transcriptome detected transcripts for 72 out of a total of 79 protein genes encoded in the chloroplast genome from radish. In contrast, the radish mitochondrial genome contains 34 protein genes, but only 16 protein transcripts were detected from the transcriptome. The transcriptome comparison between CMS and near-isogenic maintainer lines revealed 539 differentially expressed genes (DEGs, indicating that the false positive rate for comparative transcriptome profiling was clearly decreased using two groups of CMS/maintainer lines with different nuclear background. The level of 127 transcripts was increased and 412 transcripts were decreased in the CMS lines. No change in levels of transcripts except CMS-inducing orf138 was identified from the mitochondrial and chloroplast genomes. Some DEGs which would be associated with the CMS, encoding MYB and bHLH transcription factors, pentatricopeptide repeat (PPR proteins, heat shock transcription factors (HSFs and heat shock proteins (HSPs, are

  15. Capture of Mediterranean fruit flies (Diptera: Tephritidae) in dry traps baited with a food-based attractant and Jackson traps baited with trimedlure during sterile male release in Guatemala.

    Science.gov (United States)

    Midgarden, David; Ovalle, Oscar; Epsky, Nancy D; Puche, Helena; Kendra, Paul E; Rendon, Pedro; Heath, Robert R

    2004-12-01

    Captures of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), in Jackson traps baited with trimedlure were compared with captures in cylindrical open-bottom dry traps baited with a food-based synthetic attractant (ammonium acetate, putrescine, and trimethylamine). Tests were conducted in Guatemala during a sterile male release program in an area where wild flies were present in low numbers. More wild and sterile females were captured in food-based traps, and more wild and sterile males were captured in trimedlure traps. The food-based traps captured almost twice as many total (male plus female) wild flies as the trimedlure traps, but the difference was not significant. Females made up approximately 60% of the wild flies caught in the food-based attractant traps; the trimedlure traps caught no females. The ratio of capture of males in trimedlure traps to food-based traps was 6.5:1 for sterile and 1.7:1 for wild flies. Because fewer sterile males are captured in the food-based traps, there is a reduction in the labor-intensive process of examining flies for sterility. The results indicate that traps baited with food-based attractants could be used in place of the Jackson/trimedlure traps for C. capitata sterile release programs because they can monitor distributions of sterile releases and detect wild fly populations effectively; both critical components of fruit fly eradication programs by using the sterile insect technique.

  16. Inherited Sterility of Fl Male Sitotroga cerealella (Olivier) and changes in the DNA Pattern as a Result of Using Gamma irradiation

    International Nuclear Information System (INIS)

    Rizk, S.A.; Mikhaiel, A.A.

    2009-01-01

    Full grown pupae of the Angoumois grain moth, Sitotroga cerealella were irradiated with 75 and 175 Gy or gamma irradiation .The sterility percent was increased by increasing of' gamma irradiation dose. Also, the sterility percent increased in F 1 males than in parents. Gamma irradiation caused a decrease in size or the ova doles and number of oocytes. The effects of gamma rays on the DNA patterns of adult male parents and Fl males showed alterations among the controls, the treated parents and Ft individuals. Exposure to radiation caused very frequently the appearance of some extra bands and the deficiency of others in the RAPD-PCR amplification patterns of the irradiated insects. However, the similarity in DNA patterns between some normal and treated samples was interpreted by assuming, that the radiation induced damage was in regions of' the genome other than at the loci under study

  17. Comparative Analysis of Anther Transcriptome Profiles of Two Different Rice Male Sterile Lines Genotypes under Cold Stress

    Directory of Open Access Journals (Sweden)

    Bin Bai

    2015-05-01

    Full Text Available Rice is highly sensitive to cold stress during reproductive developmental stages, and little is known about the mechanisms of cold responses in rice anther. Using the HiSeq™ 2000 sequencing platform, the anther transcriptome of photo thermo sensitive genic male sterile lines (PTGMS rice Y58S and P64S (Pei’ai64S were analyzed at the fertility sensitive stage under cold stress. Approximately 243 million clean reads were obtained from four libraries and aligned against the oryza indica genome and 1497 and 5652 differentially expressed genes (DEGs were identified in P64S and Y58S, respectively. Both gene ontology (GO and Kyoto Encyclopedia of Genes and Genomes (KEGG analyses were conducted for these DEGs. Functional classification of DEGs was also carried out. The DEGs common to both genotypes were mainly involved in signal transduction, metabolism, transport, and transcriptional regulation. Most of the DEGs were unique for each comparison group. We observed that there were more differentially expressed MYB (Myeloblastosis and zinc finger family transcription factors and signal transduction components such as calmodulin/calcium dependent protein kinases in the Y58S comparison group. It was also found that ribosome-related DEGs may play key roles in cold stress signal transduction. These results presented here would be particularly useful for further studies on investigating the molecular mechanisms of rice responses to cold stress.

  18. Cytoplasmic-genetic male sterility gene provides direct evidence for some hybrid rice recently evolving into weedy rice

    Science.gov (United States)

    Zhang, Jingxu; Lu, Zuomei; Dai, Weimin; Song, Xiaoling; Peng, Yufa; Valverde, Bernal E.; Qiang, Sheng

    2015-01-01

    Weedy rice infests paddy fields worldwide at an alarmingly increasing rate. There is substantial evidence indicating that many weedy rice forms originated from or are closely related to cultivated rice. There is suspicion that the outbreak of weedy rice in China may be related to widely grown hybrid rice due to its heterosis and the diversity of its progeny, but this notion remains unsupported by direct evidence. We screened weedy rice accessions by both genetic and molecular marker tests for the cytoplasmic male sterility (CMS) genes (Wild abortive, WA, and Boro type, BT) most widely used in the production of indica and japonica three-line hybrid rice as a diagnostic trait of direct parenthood. Sixteen weedy rice accessions of the 358 tested (4.5%) contained the CMS-WA gene; none contained the CMS-BT gene. These 16 accessions represent weedy rices recently evolved from maternal hybrid rice derivatives, given the primarily maternal inheritance of this trait. Our results provide key direct evidence that hybrid rice can be involved in the evolution of some weedy rice accessions, but is not a primary factor in the recent outbreak of weedy rice in China. PMID:26012494

  19. [Social representations of male sterilization. Vasectomy as viewed by professional counselors at the Men's Clinic in Bogotá,Colombia

    Science.gov (United States)

    Viveros; Gomez; Otero

    1998-03-30

    Vasectomy service providers at the Clínica del Hombre (Men's Clinic) in Bogotá, Colombia, construct their representations concerning male sterilization on the basis of biomedical discourse, their interaction with clinic users, and their own life experiences. During provision of such services, the counselors are the health professionals who have the closest contact with these clients of the clinic. Counselors are in charge of exploring their motivations in requesting the service, in addition to providing information allowing them to take a calm, sound decision. They also directly filter demand based on their experience, knowledge, and skills, in permanent negotiation between institutional criteria (number of children and gap between them, client's age, steadiness of couple's relationship, and conviction concerning the decision), and their perception and assessment of the client. An analysis of the counselors' representations of decision-making as pertaining to vasectomy indicates that it is a relatively simple and harmless procedure as well as a liberating option in terms of family planning.

  20. Reduction of indole-3-acetic acid methyltransferase activity compensates for high-temperature male sterility in Arabidopsis.

    Science.gov (United States)

    Abbas, Mohamad; Hernández-García, Jorge; Blanco-Touriñán, Noel; Aliaga, Norma; Minguet, Eugenio G; Alabadí, David; Blázquez, Miguel A

    2018-01-01

    High temperature is a general stress factor that causes a decrease in crop yield. It has been shown that auxin application reduces the male sterility caused by exposure to higher temperatures. However, widespread application of a hormone with vast effects on plant physiology may be discouraged in many cases. Therefore, the generation of new plant varieties that locally enhance auxin in reproductive organs may represent an alternative strategy. We have explored the possibility of increasing indole-3-acetic acid (IAA) in ovaries by reducing IAA methyltransferase1 (IAMT1) activity in Arabidopsis thaliana. The iamt1 mutant showed increased auxin signalling in funiculi, which correlated with a higher growth rate of wild-type pollen in contact with mutant ovaries and premature ovule fertilization. While the production of seeds per fruit was similar in the wild type and the mutant at 20 °C, exposure to 29 °C caused a more severe decrease in fertility in the wild type than in the mutant. Loss of IAMT1 activity was also associated with the production of more nodes after flowering and higher tolerance of the shoot apical meristem to higher temperatures. As a consequence, the productivity of the iamt1 mutant under higher temperatures was more than double of that of the wild type, with almost no apparent trade-off. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  1. Comparing the Entrepreneurial Intention between Female and Male Engineering Students

    OpenAIRE

    Lo Choitung; Sun Hongyi; Law Kris

    2012-01-01

    Women business ownership contributes to entrepreneurship quality and diversity. However, the new venture creation rate of females lags far behind that of males. How to increase female entrepreneurship by entrepreneurship education is an important topic in the field. It has been reported that students’ entrepreneurial intention is a key to their future entrepreneurial behaviors. This paper aims to empirically compare the entrepreneurial intentions between female and male engineering students w...

  2. Agronomic Performance of Flue-Cured Tobacco F1 Hybrids Obtained with Different Sources of Male Sterile Cytoplasm

    Directory of Open Access Journals (Sweden)

    Berbec A

    2014-12-01

    Full Text Available Four cytoplasmic male sterile (cms F1flue-cured hybrids cv. Wiaelica × cv. Virginia Golta (VG, the male fertile analogue and the parental varieties were tested at two locations in Poland in a replicated field trial. The cms sources in the hybrids wereN. suaveolens,N. amplexicaulis,N. bigeloviiand aN. tabacumcms mutant. Under the slight to moderate pressure from black root rot present at the trial sites the hybrids showed a moderate tolerance of the disease characteristic of VG as opposed to medium strong susceptibility of Wislica. Apart from the effect of black root rot tolerance the vegetative vigor of the hybrids (plant height, leaf size, earliness was affected by cytoplasm source. The F1hybrid withN. suaveolens cytoplasm flowered approximately three days later than the remaining hybrids. Of the cms hybrids tested cmsN. bigelovii produced the tallest plants with largest mid-position leaves. Yields of cured leaves were largely influenced by black root rot and were generally higher in VG and in the hybrids than in Wislica. Leaf yields and curability were generally little affected by cms source under low pressure from black root rot. At the site with a relatively high level of black root rot infestation the yields of cmsN. suaveolens were slightly lower but the percentage of light grades slightly higher compared to those of other cms hybrids. CmsN. suaveolens was the best hybrid in terms of money returns at the low black root rot field but it was the poorest hybrid performer under high pressure from the disease. Contents of nitrogen, sugars, nicotine and ash was little affected by source of cms. There was an increased incidence of potato virus Y (PVY and white spots in cmsN. suaveolens and, to a lesser extent, in cmsN. bigelovii as compared to the remaining disease-free entries.

  3. Basigin null mutant male mice are sterile and exhibit impaired interactions between germ cells and Sertoli cells.

    Science.gov (United States)

    Bi, Jiajia; Li, Yanfen; Sun, Fengyun; Saalbach, Anja; Klein, Claudia; Miller, David J; Hess, Rex; Nowak, Romana A

    2013-08-15

    Basigin (BSG) is a multifunctional glycoprotein that plays an important role in male reproduction since male knockout (KO) mice are sterile. The Bsg KO testis lacks elongated spermatids and mature spermatozoa, a phenotype similar to that of alpha-mannosidase IIx (MX) KO mice. MX regulates formation of N-acetylglucosamine (GlcNAc) terminated N-glycans that participate in germ cell-Sertoli cell adhesion. Results showed that Bsg KO spermatocytes displayed normal homologous chromosome synapsis and progression through meiosis. However, only punctate expression of the round spermatid marker SP-10 in the acrosomal granule of germ cells of Bsg KO mice was detected indicating that spermatogenesis in Bsg KO mice was arrested at the early round spermatid stages. We observed a large increase in the number of germ cells undergoing apoptosis in Bsg KO testes. Using lectin blotting, we determined that GlcNAc terminated N-glycans are linked to BSG. GlcNAc terminated N-glycans were significantly reduced in Bsg KO testes. These observations indicate that BSG may act as a germ cell-Sertoli cell attachment molecule. Loss of BSG significantly reduced adhesion between GC-2 and SF7 cells. Moreover, wild type testes showed strong expression of N-cadherin (CDH2) while expression was greatly reduced in the testes of Bsg KO mice. In addition, the integrity of the blood-testis barrier (BTB) was compromised in Bsg KO testes. In conclusion, although some Bsg KO spermatogonia can undergo normal progression to the spermatocyte stage, BSG-mediated germ cell-Sertoli cell interactions appear to be necessary for integrity of the BTB and spermatocyte progression to mature spermatozoa. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Male Sterile2 Encodes a Plastid-Localized Fatty Acyl Carrier Protein Reductase Required for Pollen Exine Development in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Chen, W.; Shanklin, J.; Yu, X.-H.; Zhang, K.; Shi, J.; De Oliveira, S.; Schreiber, L.; Zhang, D.

    2011-10-01

    Male Sterile2 (MS2) is predicted to encode a fatty acid reductase required for pollen wall development in Arabidopsis (Arabidopsis thaliana). Transient expression of MS2 in tobacco (Nicotiana benthamiana) leaves resulted in the accumulation of significant levels of C16 and C18 fatty alcohols. Expression of MS2 fused with green fluorescent protein revealed that an amino-terminal transit peptide targets the MS2 to plastids. The plastidial localization of MS2 is biologically important because genetic complementation of MS2 in ms2 homozygous plants was dependent on the presence of its amino-terminal transit peptide or that of the Rubisco small subunit protein amino-terminal transit peptide. In addition, two domains, NAD(P)H-binding domain and sterile domain, conserved in MS2 and its homologs were also shown to be essential for MS2 function in pollen exine development by genetic complementation testing. Direct biochemical analysis revealed that purified recombinant MS2 enzyme is able to convert palmitoyl-Acyl Carrier Protein to the corresponding C16:0 alcohol with NAD(P)H as the preferred electron donor. Using optimized reaction conditions (i.e. at pH 6.0 and 30 C), MS2 exhibits a K{sub m} for 16:0-Acyl Carrier Protein of 23.3 {+-} 4.0 {mu}m, a V{sub max} of 38.3 {+-} 4.5 nmol mg{sup -1} min{sup -1}, and a catalytic efficiency/K{sub m} of 1,873 m{sup -1} s{sup -1}. Based on the high homology of MS2 to other characterized fatty acid reductases, it was surprising that MS2 showed no activity against palmitoyl- or other acyl-coenzyme A; however, this is consistent with its plastidial localization. In summary, genetic and biochemical evidence demonstrate an MS2-mediated conserved plastidial pathway for the production of fatty alcohols that are essential for pollen wall biosynthesis in Arabidopsis.

  5. Post-translational mechanisms are associated with fertility restoration of cytoplasmic male sterility in sugar beet (Beta vulgaris).

    Science.gov (United States)

    Kitazaki, Kazuyoshi; Arakawa, Takumi; Matsunaga, Muneyuki; Yui-Kurino, Rika; Matsuhira, Hiroaki; Mikami, Tetsuo; Kubo, Tomohiko

    2015-07-01

    Genetic conflict between cytoplasmically inherited elements and nuclear genes arising from their different transmission patterns can be seen in cytoplasmic male sterility (CMS), the mitochondrion-encoded inability to shed functional pollen. CMS is associated with a mitochondrial open reading frame (ORF) that is absent from non-sterility inducing mitochondria (S-orf). Nuclear genes that suppress CMS are called restorer-of-fertility (Rf) genes. Post-transcriptional and translational repression of S-orf mediates the molecular action of Rf that encodes a class of RNA-binding proteins with pentatricopeptide repeat (PPR) motifs. Besides the PPR-type of Rfs, there are also non-PPR Rfs, but the molecular interactions between non-PPR Rf and S-orf have not been described. In this study, we investigated the interaction of bvORF20, a non-PPR Rf from sugar beet (Beta vulgaris), with preSatp6, the S-orf from sugar beet. Anthers expressing bvORF20 contained a protein that interacted with preSATP6 protein. Analysis of anthers and transgenic calli expressing a FLAG-tagged bvORF20 suggested the binding of preSATP6 to bvORF20. To see the effect of bvORF20 on preSATP6, which exists as a 250-kDa protein complex in CMS plants, signal bands of preSATP6 in bvORF20-expressing and non-expressing anthers were compared by immunoblotting combined with Blue Native polyacrylamide gel electrophoresis. The signal intensity of the 250-kDa band decreased significantly, and 200- and 150-kDa bands appeared in bvORF20-expressing anthers. Transgenic callus expressing bvORF20 also generated the 200- and 150-kDa bands. The 200-kDa complex is likely to include both preSATP6 and bvORF20. Post-translational interaction between preSATP6 and bvORF20 appears to alter the higher order structure of preSATP6 that may lead to fertility restoration in sugar beet. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  6. Comparative transcript profiling of a male sterile cybrid pummelo and its fertile type revealed altered gene expression related to flower development.

    Directory of Open Access Journals (Sweden)

    Bei-Bei Zheng

    Full Text Available Male sterile and seedless characters are highly desired for citrus cultivar improvement. In our breeding program, a male sterile cybrid pummelo, which could be considered as a variant of male fertile pummelo, was produced by protoplast fusion. Herein, ecotopic stamen primordia initiation and development were detected in this male sterile cybrid pummelo. Histological studies revealed that the cybrid showed reduced petal development in size and width, and retarded stamen primordia development. Additionally, disorganized cell proliferation was also detected in stamen-like structures (fused to petals and/or carpel. To gain new insight into the underlying mechanism, we compared, by RNA-Seq analysis, the nuclear gene expression profiles of floral buds of the cybrid with that of fertile pummelo. Gene expression profiles which identified a large number of differentially expressed genes (DEGs between the two lines were captured at both petal primordia and stamen primordia distinguishable stages. For example, nuclear genes involved in nucleic acid binding and response to hormone synthesis and metabolism, genes required for floral bud identification and expressed in particular floral whorls. Furthermore, in accordance with flower morphology of the cybrid, expression of PISTILLATA (PI was reduced in stamen-like structures, even though it was restricted to correct floral whorls. Down-regulated expression of APETALA3 (AP3 coincided with that of PI. These finding indicated that, due to their whorl specific effects in flower development, citrus class-B MADS-box genes likely constituted 'perfect targets' for CMS retrograde signaling, and that dysfunctional mitochondria seemed to cause male sterile phenotype in the cybrid pummelo.

  7. Effect of X-ray Irradiation on the Male Moths of Two Tropical Races of the Silkworm and Inheritance of Induced Sterility in the Progenies

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    G. Subramanya

    2010-01-01

    Full Text Available Newly emerged male moths of silkworm Bombyx mori were treated with in 24 h of eclosion irradiated with two independent doses of 50 Gy and 100 Gy X-rays. The effects of X-rays in the parental generation have indicated significant increase of unfertilized and unhatched eggs followed by significant reduction in the hatchability in the treated batches compared to control. The inheritance of induced sterility was examined in the succeeding generations by rearing the F 1 , F 2 and F 3 silkworm progenies and by crossing the progenies of treated males with untreated female moths. It is evident from the results that the number of hatched eggs gradually increased from F 1 –F 3 generations. Thus, the results showed that the egg hatchability do not remain constant at every generation and hatching tendency of eggs increase in the progenies of treated batches. The mechanism of inherited sterility was discussed.

  8. A novel comprehensive approach for human vascular allografts cryopreservation and radiation sterilization for the tissue engineering industry

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    Lauk-Dubitsky S.E.

    2015-12-01

    Full Text Available Aim: to verify new techniques for human cadaveric vascular allografts cryopreservation, thawing and sterilization for the tissue engineering purposes. We use polydimethylsiloxane (PDMS as a well-known, promising coolant. This allowed us to completely omit any cryoprotective or vitrifying solutions. Using of PDMS also makes possible an applying these allografts directly after freezing and decellularization and also it will also provide an opportunity to develop secure protocols of tissue— engineered vascular conduits cryopreservation. Matherial and methods. After mathematical modeling of cooling process and its validation the experiment for sealed (isolated freezing at low temperature conditions of 30 femoral arterial segments has been conducted. The segments were at least 10 cm in length and taken from 15 cadaveric donors in the age of 65-85 years. The freezing process was carried out using the abovementioned coolant— PDMS, and then physico-mechanical properties of these allografts were evaluated with the special Instron machine. According to the results obtained, a modeling of their sterilization conditions was conducted (the grafts were freezed. Results. By physico-mechanical properties validation and restricted histological analysis it was shown that there was an accordance between freezed/thawed allografts properties and native vessels. Conclusion. The abovementioned approach for allografts cryopreservation and thawing was efficient enough for further work in this direction.

  9. Genetic engineering technology for the improvement of the sterile insect technique. Proceedings of a final research co-ordination meeting

    International Nuclear Information System (INIS)

    1998-01-01

    Since the beginning of the joint FAO/IAEA programme on the research and development of insect pest control methodology, emphasis has been placed on the basic and applied aspects of implementing the sterile insect technique (SIT). Special emphasis has always been directed at the assembly of technological progress into workable systems that can be implemented in developing countries. The general intention is to solve problems associated with insect pests that have an adverse impact on production of food and fibre. For several insect species SIT has proven to be a powerful method for control. This includes the New World screwworm fly (Cochliomyia hominivorox), the Mediterranean fruit fly (Ceratitis capitata), the melon fly (Bactrocera cucurbitae), the Queensland fruit fly (Bactrocera tryoni) and one tsetse fly species (Glossina austeni). Improvements of the SIT are possible, especially through the use of molecular techniques. The final report of the Co-ordinated Research Programme on ''Genetic Engineering Technology for the Improvement of the Sterile Insect Technique'' highlights the progress made towards the development of transformation systems for non-drosophilid insects and the research aimed at the identification and engineering of potential target genes or traits

  10. Restorer-of-Fertility Mutations Recovered in Transposon-Active Lines of S Male-Sterile Maize

    Directory of Open Access Journals (Sweden)

    Susan Gabay-Laughnan

    2018-01-01

    Full Text Available Mitochondria execute key pathways of central metabolism and serve as cellular sensing and signaling entities, functions that depend upon interactions between mitochondrial and nuclear genetic systems. This is exemplified in cytoplasmic male sterility type S (CMS-S of Zea mays, where novel mitochondrial open reading frames are associated with a pollen collapse phenotype, but nuclear restorer-of-fertility (restorer mutations rescue pollen function. To better understand these genetic interactions, we screened Activator-Dissociation (Ac-Ds, Enhancer/Suppressor-mutator (En/Spm, and Mutator (Mu transposon-active CMS-S stocks to recover new restorer mutants. The frequency of restorer mutations increased in transposon-active stocks compared to transposon-inactive stocks, but most mutants recovered from Ac-Ds and En/Spm stocks were unstable, reverting upon backcrossing to CMS-S inbred lines. However, 10 independent restorer mutations recovered from CMS-S Mu transposon stocks were stable upon backcrossing. Many restorer mutations condition seed-lethal phenotypes that provide a convenient test for allelism. Eight such mutants recovered in this study included one pair of allelic mutations that were also allelic to the previously described rfl2-1 mutant. Targeted analysis of mitochondrial proteins by immunoblot identified two features that consistently distinguished restored CMS-S pollen from comparably staged, normal-cytoplasm, nonmutant pollen: increased abundance of nuclear-encoded alternative oxidase relative to mitochondria-encoded cytochrome oxidase and decreased abundance of mitochondria-encoded ATP synthase subunit 1 compared to nuclear-encoded ATP synthase subunit 2. CMS-S restorer mutants thus revealed a metabolic plasticity in maize pollen, and further study of these mutants will provide new insights into mitochondrial functions that are critical to pollen and seed development.

  11. Detection of the Diversity of Cytoplasmic Male Sterility Sources in Broccoli (Brassica Oleracea var. Italica) Using Mitochondrial Markers.

    Science.gov (United States)

    Shu, Jinshuai; Liu, Yumei; Li, Zhansheng; Zhang, Lili; Fang, Zhiyuan; Yang, Limei; Zhuang, Mu; Zhang, Yangyong; Lv, Honghao

    2016-01-01

    Broccoli (Brassica oleracea var. italica) is an important commercial vegetable crop. As part of an efficient pollination system, cytoplasmic male sterility (CMS) has been widely used for broccoli hybrid production. Identifying the original sources of CMS in broccoli accessions has become an important part of broccoli breeding. In this study, the diversity of the CMS sources of 39 broccoli accessions, including 19 CMS lines and 20 hybrids, were analyzed using mitochondrial markers. All CMS accessions contained the ogu orf138-related DNA fragment and the key genes of nap CMS, pol CMS, and tour CMS were not detected. The 39 CMS accessions were divided into five groups using six orf138-related and two simple sequence repeat markers. We observed that ogu CMS R3 constituted 79.49% of the CMS sources. CMS6 and CMS26 were differentiated from the other accessions using a specific primer. CMS32 was distinguished from the other accessions based on a 78-nucleotide deletion at the same locus as the orf138-related sequence. When the coefficient was about 0.90, five CMS accessions (13CMS6, 13CMS23, 13CMS24, 13CMS37, and 13CMS39) exhibiting abnormal floral organs with poor seed setting were grouped together. The polymerase chain reaction amplification profiles for these five accessions differed from those of the other accessions. We identified eight useful molecular markers that can be used to detect CMS types during broccoli breeding. Our data also provide important information relevant to future studies on the possible origins and molecular mechanisms of CMS in broccoli.

  12. Comparative Transcriptome Analysis between the Cytoplasmic Male Sterile Line NJCMS1A and Its Maintainer NJCMS1B in Soybean (Glycine max (L. Merr..

    Directory of Open Access Journals (Sweden)

    Jiajia Li

    Full Text Available The utilization of soybean heterosis is probably one of the potential approaches in future yield breakthrough as was the situation in rice breeding in China. Cytoplasmic male sterility (CMS plays an important role in the production of hybrid seeds. However, the molecular mechanism of CMS in soybean remains unclear.The comparative transcriptome analysis between cytoplasmic male sterile line NJCMS1A and its near-isogenic maintainer NJCMS1B in soybean was conducted using Illumina sequencing technology. A total of 88,643 transcripts were produced in Illumina sequencing. Then 56,044 genes were obtained matching soybean reference genome. Three hundred and sixty five differentially expressed genes (DEGs between NJCMS1A and NJCMS1B were screened by threshold, among which, 339 down-regulated and 26 up-regulated in NJCMS1A compared to in NJCMS1B. Gene Ontology (GO annotation showed that 242 DEGs were annotated to 19 functional categories. Clusters of Orthologous Groups of proteins (COG annotation showed that 265 DEGs were classified into 19 categories. Kyoto Encyclopedia of Genes and Genomes (KEGG analysis showed that 46 DEGs were assigned to 33 metabolic pathways. According to functional and metabolic pathway analysis combined with reported literatures, the relations between some key DEGs and the male sterility of NJCMS1A were discussed. qRT-PCR analysis validated that the gene expression pattern in RNA-Seq was reliable. Finally, enzyme activity assay showed that energy supply was decreased in NJCMS1A compared to in NJCMS1B.We concluded that the male sterility of NJCMS1A might be related to the disturbed functions and metabolism pathways of some key DEGs, such as DEGs involved in carbohydrate and energy metabolism, transcription factors, regulation of pollen development, elimination of reactive oxygen species (ROS, cellular signal transduction, and programmed cell death (PCD etc. Future research will focus on cloning and transgenic function validation of

  13. Analysis of a Partial Male-Sterile Mutant of Arabidopsis thaliana Isolated from a Low-Energy Argon Ion Beam Mutagenized Pool

    International Nuclear Information System (INIS)

    Xu Min; Bian Po; Wu Yuejin; Yu Zengliang

    2008-01-01

    A screen for Arabidopsis fertility mutants, mutagenized by low-energy argon ion beam, yielded two partial male-sterile mutants tc243-1 and tc243-2 which have similar phenotypes. tc243-2 was investigated in detail. The segregation ratio of the mutant phenotypes in the M2 pools suggested that mutation behaved as single Mendelian recessive mutations. tc243 showed a series of mutant phenotypes, among which partial male-sterile was its striking mutant characteristic. Phenotype analysis indicates that there are four factors leading to male sterility. a. Floral organs normally develop inside the closed bud, but the anther filaments do not elongate sufficiently to position the locules above the stigma at anthesis. b. The anther locules do not dehisce at the time of flower opening (although limited dehiscence occurs later). c. Pollens of mutant plants develop into several types of pollens at the trinucleated stage, as determined by staining with DAPI (4',6-diamidino-2-phenylindole), which shows a variable size, shape and number of nucleus. d. The viability of pollens is lower than that of the wild type on the germination test in vivo and vitro.

  14. Transcriptome sequencing and de novo analysis of a cytoplasmic male sterile line and its near-isogenic restorer line in chili pepper (Capsicum annuum L..

    Directory of Open Access Journals (Sweden)

    Chen Liu

    Full Text Available BACKGROUND: The use of cytoplasmic male sterility (CMS in F1 hybrid seed production of chili pepper is increasingly popular. However, the molecular mechanisms of cytoplasmic male sterility and fertility restoration remain poorly understood due to limited transcriptomic and genomic data. Therefore, we analyzed the difference between a CMS line 121A and its near-isogenic restorer line 121C in transcriptome level using next generation sequencing technology (NGS, aiming to find out critical genes and pathways associated with the male sterility. RESULTS: We generated approximately 53 million sequencing reads and assembled de novo, yielding 85,144 high quality unigenes with an average length of 643 bp. Among these unigenes, 27,191 were identified as putative homologs of annotated sequences in the public protein databases, 4,326 and 7,061 unigenes were found to be highly abundant in lines 121A and 121C, respectively. Many of the differentially expressed unigenes represent a set of potential candidate genes associated with the formation or abortion of pollen. CONCLUSIONS: Our study profiled anther transcriptomes of a chili pepper CMS line and its restorer line. The results shed the lights on the occurrence and recovery of the disturbances in nuclear-mitochondrial interaction and provide clues for further investigations.

  15. Irradiation Sterilized Gelatin-Water-Glycerol Ternary Gel as an Injectable Carrier for Bone Tissue Engineering.

    Science.gov (United States)

    Zhao, Yantao; Han, Liwei; Yan, Jun; Li, Zhonghai; Wang, Fuli; Xia, Yang; Hou, Shuxun; Zhong, Hongbin; Zhang, Feimin; Gu, Ning

    2017-01-01

    Injectable gelatin gels offer an attractive option for filling bone defects. The challenge is to fabricate gelatin gels with optimal gelation properties, which can be irradiation sterilized. Here, a gelatin-water-glycerol (GWG) gel is reported for use as a broad-spectrum injectable carrier. This ternary gel is high in glycerol and low in water, and remains stable after gamma irradiation at doses (25 kGy). As an injectable gel, it remains a viscous solution at gelatin concentrations ≤2.0%, at room temperature. Its storage modulus increases dramatically and eventually exceeds the loss modulus around 46-50 °C, indicating a transition from a liquid-like state to an elastic gel-like state. This ternary gel ranges significantly in terms of storage modulus (12-1700 Pa) while demonstrating a narrow pH range (5.58-5.66), depending on the gelatin concentration. Therefore, it can be loaded with a variety of materials. It is highly cytocompatible compared with saline in vivo and culture media in vitro. When loaded with demineralized bone matrix, the composites show favorable injectability, and excellent osteogenesis performance, after irradiation. These features can be attributed to high hydrophilicity and fast degradability. These findings justify that this ternary gel is promising as an irradiation-sterilized and universal injectable delivery system. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Influence of Genetic Drift of Restoring Gene (Rf on Seed Purity of Yuetai A, a Honglian-Type Cytoplasmic Male Sterile Line in Hybrid Rice

    Directory of Open Access Journals (Sweden)

    Ji-feng Wang

    2008-06-01

    Full Text Available The seed samples of Yuetai A, a Honglian (HL type cytoplasmic male sterile (CMS line in hybrid rice were investigated to assess the seed purity and to analyze the cause of off-type plants by imitating the biological contaminant to Yuetai A in Nanjing, Jiangsu Province and Lingshui, Hainan Province during 2004–2006. The seed impurity of Yuetai A mainly resulted from the genetic drift of restoring fertility gene (Rf after biological contamination but not from its sterility unstability. All of the ten maintainer lines, five restorer lines and three thermo-sensitive genic male sterile lines used in the study could pollinate Yuetai A and Yuetai B to produce F1 plants, directly or indirectly resulting in Rf-gene drifting into Yuetai A and generating ‘iso-cytoplasm restoring-generations’. Furthermore, high outcrossing rate and similar heading date of Yuetai A with many varieties used in rice production might easily result in the biological contamination. After removing all plants with Rf-gene mixed in Yuetai A and preventing Rf-gene drifting into Yuetai A, the seed purity of Yuetai A and Yuetai B had been raised to 100%.

  17. Improving Blast Resistance of a Thermo-Sensitive Genic Male Sterile Rice Line GD-8S by Molecular Marker-Assisted Selection

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    Wu-ge LIU

    2008-09-01

    Full Text Available The broad-spectrum blast resistance gene Pi-1, from donor line BL122, was introduced into a thermo-sensitive genic male sterile rice line GD-8S, which possessed good grain quality but high susceptibility to rice blast, by using backcross breeding and molecular marker-assisted selection. Five elite improved male sterile lines, RGD8S-1, RGD8S-2, RGD8S-3, RGD8S-4 and RGD8S-5, were selected based on the results of molecular marker analysis, spikelet sterility, recovery rate of genetic background and agronomic traits. Thirty-three representative blast isolates collected from Guangdong Province, China were used to inoculate the improved lines and the original line GD-8S artificially. The resistance frequencies of the improved lines ranged from 76.47% to 100%, much higher than that of the original line GD-8S (9.09%. On the agronomic characters, there were no significant differences between the improved lines and GD-8S except for flag leaf length and panicle number per plant. The improved lines could be used for breeding hybrid rice with high blast resistance.

  18. Comparative analysis of mitochondrial genomes between a wheat K-type cytoplasmic male sterility (CMS line and its maintainer line

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    Liu Dongcheng

    2011-03-01

    Full Text Available Abstract Background Plant mitochondria, semiautonomous organelles that function as manufacturers of cellular ATP, have their own genome that has a slow rate of evolution and rapid rearrangement. Cytoplasmic male sterility (CMS, a common phenotype in higher plants, is closely associated with rearrangements in mitochondrial DNA (mtDNA, and is widely used to produce F1 hybrid seeds in a variety of valuable crop species. Novel chimeric genes deduced from mtDNA rearrangements causing CMS have been identified in several plants, such as rice, sunflower, pepper, and rapeseed, but there are very few reports about mtDNA rearrangements in wheat. In the present work, we describe the mitochondrial genome of a wheat K-type CMS line and compare it with its maintainer line. Results The complete mtDNA sequence of a wheat K-type (with cytoplasm of Aegilops kotschyi CMS line, Ks3, was assembled into a master circle (MC molecule of 647,559 bp and found to harbor 34 known protein-coding genes, three rRNAs (18 S, 26 S, and 5 S rRNAs, and 16 different tRNAs. Compared to our previously published sequence of a K-type maintainer line, Km3, we detected Ks3-specific mtDNA (> 100 bp, 11.38% and repeats (> 100 bp, 29 units as well as genes that are unique to each line: rpl5 was missing in Ks3 and trnH was absent from Km3. We also defined 32 single nucleotide polymorphisms (SNPs in 13 protein-coding, albeit functionally irrelevant, genes, and predicted 22 unique ORFs in Ks3, representing potential candidates for K-type CMS. All these sequence variations are candidates for involvement in CMS. A comparative analysis of the mtDNA of several angiosperms, including those from Ks3, Km3, rice, maize, Arabidopsis thaliana, and rapeseed, showed that non-coding sequences of higher plants had mostly divergent multiple reorganizations during the mtDNA evolution of higher plants. Conclusion The complete mitochondrial genome of the wheat K-type CMS line Ks3 is very different from that of

  19. Supportive Organisational Cultures and their effects on Male Civil Engineers

    Directory of Open Access Journals (Sweden)

    Valarie Francis

    2012-11-01

    Full Text Available Substantial changes, not only in the demographic composition of the Australian workforce, but also,in the roles and expectations of men and women, have led to organisational and employee attempts to reconcile work and non-work demands. Research suggests that when work-family balance practices are introduced they can greatly enhance organisational efficency. However factors embedded in the organisational culture can undermine these policies rendering them ineffective. This quantitative study examined the relationship between the perceptions of a supportive work culture and some work and non-work experiences of Australian male civil engineers. The research investigated the prevalence of organisational values supportive of work-life balances as well as the level of work-family conflict perceived by those engineers. This paper reports some initial results of the study. These indicated that male civil engineers experienced moderate levels of work-family conflict but do not perceive their organisations to be very supportive of employee nneeds to balance work and personal life. However those that reported a supportive work environment also reported higher levels of organisational commitment, greater job and life satisfaction as well as lower level of work-family conflict and lower intentions to quit. The implications of the findings for organisations employing civil engineers are discussed.   

  20. Spacecraft sterilization.

    Science.gov (United States)

    Kalfayan, S. H.

    1972-01-01

    Spacecraft sterilization is a vital factor in projects for the successful biological exploration of other planets. The microorganisms of major concern are the fungi and bacteria. Sterilization procedures are oriented toward the destruction of bacterial spores. Gaseous sterilants are examined, giving attention to formaldehyde, beta-propiolactone, ethylene oxide, and the chemistry of the bactericidal action of sterilants. Radiation has been seriously considered as another method for spacecraft sterilization. Dry heat sterilization is discussed together with the effects of ethylene oxide decontamination and dry heat sterilization on materials.

  1. Comparative transcript profiling of alloplasmic male-sterile lines revealed altered gene expression related to pollen development in rice (Oryza sativa L.).

    Science.gov (United States)

    Hu, Jihong; Chen, Guanglong; Zhang, Hongyuan; Qian, Qian; Ding, Yi

    2016-08-05

    Cytoplasmic male sterility (CMS) is an ideal model for investigating the mitochondrial-nuclear interaction and down-regulated genes in CMS lines which might be the candidate genes for pollen development in rice. In this study, a set of rice alloplasmic sporophytic CMS lines was obtained by successive backcrossing of Meixiang B, with three different cytoplasmic types: D62A (D type), ZS97A (WA type) and XQZ-A (DA type). Using microarray, the anther transcript profiles of the three indica rice CMS lines revealed 622 differentially expressed genes (DEGs) in each of the three CMS lines compared with the maintainer line Meixiang B. GO and MapMan analysis indicated that these DEGs were mainly involved in lipid metabolism and cell wall organization. Compared with the gene expression of sporophytic and gametophytic CMS lines, 303 DEGs were identified and 56 of them were down-regulated in all the CMS lines of rice. These down-regulated DEGs in the CMS lines were found to be involved in tapetum or cell wall formation and their suppressed expression might be related to male sterility. Weighted gene co-expression network analysis (WGCNA) revealed that two modules were significantly associated with male sterility and many hub genes that were differentially expressed in the CMS lines. A large set of putative genes involved in anther development was identified in the present study. The results will give some information for the nuclear gene regulation by different cytoplasmic genotypes and provide a rich resource for further functional research on the pollen development in rice.

  2. Mapping and Identifying a Candidate Gene (Bnmfs for Female-Male Sterility through Whole-Genome Resequencing and RNA-Seq in Rapeseed (Brassica napus L.

    Directory of Open Access Journals (Sweden)

    Changcai Teng

    2017-12-01

    Full Text Available In oilseed crops, carpel and stamen development play vital roles in pollination and rapeseed yield, but the genetic mechanisms underlying carpel and stamen development remain unclear. Herein, a male- and female-sterile mutant was obtained in offspring of a (Brassica napus cv. Qingyou 14 × (Qingyou 14 × B. rapa landrace Dahuang cross. Subsequently, F2–F9 populations were generated through selfing of the heterozygote plants among the progeny of each generation. The male- and female-sterility exhibited stable inheritance in successive generations and was controlled by a recessive gene. The mutant kept the same chromosome number (2n = 38 as B. napus parent but showed abnormal meiosis for male and female. One candidate gene for the sterility was identified by simple sequence repeat (SSR and insertion deletion length polymorphism (InDel markers in F7–F9 plants, and whole-genome resequencing with F8 pools and RNA sequencing with F9 pools. Whole-genome resequencing found three candidate intervals (35.40–35.68, 35.74–35.75, and 45.34–46.45 Mb on chromosome C3 in B. napus and candidate region for Bnmfs was narrowed to approximately 1.11-Mb (45.34–46.45 M by combining SSR and InDel marker analyses with whole-genome resequencing. From transcriptome profiling in 0–2 mm buds, all of the genes in the candidate interval were detected, and only two genes with significant differences (BnaC03g56670D and BnaC03g56870D were revealed. BnaC03g56870D was a candidate gene that shared homology with the CYP86C4 gene of Arabidopsis thaliana. Quantitative reverse transcription (qRT-PCR analysis showed that Bnmfs primarily functioned in flower buds. Thus, sequencing and expression analyses provided evidence that BnaC03g56870D was the candidate gene for male and female sterility in the B. napus mutant.

  3. Development of an ideal plant type and male sterility system in sesame suitable for summer rice fallow in the coastal regions of Tamil Nadu

    International Nuclear Information System (INIS)

    Ganesan, J.

    2001-01-01

    In Tamil Nadu, sesame growing on available residual soil moisture after the rice harvest is expanding. In order to achieve higher and more reliable yields under these conditions, a more suitable plant type is needed: with shorter stature and growing period, moderate basal branching and higher productivity. Seeds of 6 varieties were treated with gamma rays, diethyl sulphate (DES) and ethyl methane sulphonate (EMS). The M 1 -M 4 generations were studied and several promising mutants were selected. Among them were also male sterile mutants; it is thought that such mutants will assist in producing hybrid varieties which will give the desired yield breakthrough. (author)

  4. Reversible Sterilization

    Science.gov (United States)

    Largey, Gale

    1977-01-01

    Notes that difficult questions arise concerning the use of sterilization for alleged eugenic and euthenic purposes. Thus, how reversible sterilization will be used with relation to the poor, mentally ill, mentally retarded, criminals, and minors, is questioned. (Author/AM)

  5. Sterilization in the United States

    Science.gov (United States)

    Bartz, Deborah; Greenberg, James A

    2008-01-01

    Unintended pregnancies are expensive for patients and for society in terms of medical costs, the cost of caring for more children, and the cost to personal and professional goals. Sterilization is the most common contraceptive method utilized by couples in the United States. Given technological advances over the past few decades, male and female surgical sterilization has become a safe, convenient, easy, and highly effective birth control method for the long term. This article reviews current male and female sterilization options. PMID:18701927

  6. Overexpression of rice black-streaked dwarf virus p7-1 in Arabidopsis results in male sterility due to non-dehiscent anthers.

    Directory of Open Access Journals (Sweden)

    Feng Sun

    Full Text Available Rice black-streaked dwarf virus (RBSDV, a member of the genus Fijivirus in the family Reoviridae, is propagatively transmitted by the small brown planthopper (Laodelphax striatellus Fallén. RBSDV causes rice black-streaked dwarf and maize rough dwarf diseases, which lead to severe yield losses in crops in China. Although several RBSDV proteins have been studied in detail, the functions of the nonstructural protein P7-1 are still largely unknown. To investigate the role of the P7-1 protein in virus pathogenicity, transgenic Arabidopsis thaliana plants were generated in which the P7-1 gene was expressed under the control of the 35S promoter. The RBSDV P7-1-transgenic Arabidopsis plants (named P7-1-OE were male sterility. Flowers and pollen from P7-1-transgenic plants were of normal size and shape, and anthers developed to the normal size but failed to dehisce. The non-dehiscent anthers observed in P7-1-OE were attributed to decreased lignin content in the anthers. Furthermore, the reactive oxygen species levels were quite low in the transgenic plants compared with the wild type. These results indicate that ectopic expression of the RBSDV P7-1 protein in A. thaliana causes male sterility, possibly through the disruption of the lignin biosynthesis and H2O2-dependent polymerization pathways.

  7. Comparative Analysis of the Cytology and Transcriptomes of the Cytoplasmic Male Sterility Line H276A and Its Maintainer Line H276B of Cotton (Gossypium barbadense L.

    Directory of Open Access Journals (Sweden)

    Xiangjun Kong

    2017-10-01

    Full Text Available In this study, the tetrad stage of microspore development in a new cotton (Gossypium barbadense L. cytoplasmic male sterility (CMS line, H276A, was identified using paraffin sections at the abortion stage. To explore the molecular mechanism underlying CMS in cotton, a comparative transcriptome analysis between the CMS line H276A and its maintainer line H276B at the tetrad stage was conducted using an Illumina HiSeq 4000 platform. The comparison of H276A with H276B revealed a total of 64,675 genes, which consisted of 59,255 known and 5420 novel genes. An analysis of the two libraries with a given threshold yielded a total of 3603 differentially expressed genes (DEGs, which included 1363 up- and 2240 down-regulated genes. Gene Ontology (GO annotation showed that 2171 DEGs were distributed into 38 categories, and a Kyoto Encyclopedia of Genes and Genomes (KEGG analysis showed that 2683 DEGs were classified into 127 groups. Thirteen DEGs were randomly selected and detected by quantitative reverse-transcribed PCR (qRT-PCR, and the results indicated that the transcriptome sequencing results were reliable. The bioinformatic analysis results in conjunction with previously reported data revealed key DEGs that might be associated with the male sterility features of H276A. Our results provide a comprehensive foundation for understanding anther development and will accelerate the study of the molecular mechanisms of CMS in cotton.

  8. Overexpression of rice black-streaked dwarf virus p7-1 in Arabidopsis results in male sterility due to non-dehiscent anthers.

    Science.gov (United States)

    Sun, Feng; Yuan, Xia; Xu, Qiufang; Zhou, Tong; Fan, Yongjian; Zhou, Yijun

    2013-01-01

    Rice black-streaked dwarf virus (RBSDV), a member of the genus Fijivirus in the family Reoviridae, is propagatively transmitted by the small brown planthopper (Laodelphax striatellus Fallén). RBSDV causes rice black-streaked dwarf and maize rough dwarf diseases, which lead to severe yield losses in crops in China. Although several RBSDV proteins have been studied in detail, the functions of the nonstructural protein P7-1 are still largely unknown. To investigate the role of the P7-1 protein in virus pathogenicity, transgenic Arabidopsis thaliana plants were generated in which the P7-1 gene was expressed under the control of the 35S promoter. The RBSDV P7-1-transgenic Arabidopsis plants (named P7-1-OE) were male sterility. Flowers and pollen from P7-1-transgenic plants were of normal size and shape, and anthers developed to the normal size but failed to dehisce. The non-dehiscent anthers observed in P7-1-OE were attributed to decreased lignin content in the anthers. Furthermore, the reactive oxygen species levels were quite low in the transgenic plants compared with the wild type. These results indicate that ectopic expression of the RBSDV P7-1 protein in A. thaliana causes male sterility, possibly through the disruption of the lignin biosynthesis and H2O2-dependent polymerization pathways.

  9. 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

  10. Effect of symbiotic bacteria added to the larval environment on the quality of the sterile male Mediterranean fruit fly, Ceratitis capitata

    International Nuclear Information System (INIS)

    Fekiri, Abdelwaheb; Arfaoui, Chaker

    2009-01-01

    The program of fight against Ceratite being based on the TIS becomes increasingly efficient when one controls these various factors well mainly the performances of the produced sterile males. While basing itself on the symbiotic relation between the bacteria present in the intestine of Ceratite and the latter, we have in this present adopted work at a method of breeding which could improve qualities of the male. This method consists in introducing certain beneficial bacteria in Ceratite (Pseudomonas, Citrobacter and Klebsiella) into the medium of breeding following various combinations. The effect of these bacteria was analyzed by carrying out various tests of quality control to release the parameters of quality (Productivity, Poids, Emergence and Aptitude for the flight) and the parameters of the sexual behavior (Latency time, Duration of coupling and competitiveness). (author)

  11. Field performance of Lynfield and McPhail traps for monitoring male and female sterile Bactrocera tryoni (Froggatt) and wild Dacus newmani (Perkins).

    Science.gov (United States)

    Dominiak, Bernie C; Nicol, Helen I

    2010-07-01

    McPhail traps, baited with protein food lure, are used worldwide for surveillance of many species of fruit flies. Queensland fruit fly (Qfly) Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) is a native Australian fruit fly and normally monitored using Lynfield traps baited with cuelure. On some occasions, McPhail traps with wet food lures are deployed to detect female flies or to find the incursion epicentre. This paper reviews field results on the merits of Lynfield and McPhail traps for detection of male and female Qfly. Following release of equal numbers of sterile males and females, Lynfield traps baited with cuelure captured more Qfly males than protein autolysate or orange concentrate in McPhail traps. Significantly more male than female Qfly were captured in McPhail traps baited with protein autolysate or orange. There was no significant difference between orange concentrate lure and protein autolysate lure in attracting either males or females. Another Australian native fruit fly, Dacus newmani (Perkins), was attracted to cuelure in Lynfield traps but not to either lure in McPhail traps. The data obtained run counter to the reputation of McPhail traps baited with protein autolysate or orange concentrate as a specialist lure/trap combination for female Qfly. Copyright (c) 2010 Society of Chemical Industry.

  12. Exposure to trace amounts of sulfonylurea herbicide tribenuron-methyl causes male sterility in 17 species or subspecies of cruciferous plants.

    Science.gov (United States)

    Yu, Cheng-Yu; Dong, Jun-Gang; Hu, Sheng-Wu; Xu, Ai-Xia

    2017-06-01

    For most cruciferous plants, which are known as important crops and a number of weeds, hybrid breeding is hampered by the unavailability of a pollination control system. Male sterility induced by a gametocide can be useful for the utilization of plant heterosis. The gametocidal effect of sulfonylurea herbicide tribenuron-methyl was tested across seventeen cruciferous species or subspecies including Brassica juncea, B. carinata, B. oleracea ssp. capitata, B. oleracea ssp. acephala, B. rapa ssp. pekinensis, B. rapa ssp. chinensis, B. rapa ssp. parachinensis, B. nigra, Orychophragmus violaceus, Matthiola incana, Raphanus sativa, Sisymbrium altissimum, Eruca sativa, Sinapis alba, Sinapis arvensis, Capsella bursa-pastoris and Camelina sativa. The plants of 23 cultivars in these species or subspecies were foliar sprayed with 10 ml of 0.2 or 0.4 mg/L of tribenuron-methyl before the vacuolated microspore formed in the largest flower buds; the application was repeated ten to twelve days afterwards. Tribenuron-methyl exposure significantly changed the flowering phenology and reproductive function. The treated plants demonstrated a one to four day delay in flowering time and a shortened duration of flowering, as well as other slight phytotoxic effects including a reduction in plant height and floral organ size. Approximately 80% to 100% male sterility, which was estimated by both pollen staining and selfing seed-set rate, was induced in the plants. As a result, plants were rendered functionally able to out-cross, with an average 87% and 54% manually pollinated seed-set rate compared to the corresponding controls at the 0.2 mg/L and 0.4 mg/L doses, respectively. The results suggested that male reproductive function was much more sensitive to tribenuron-methyl exposure than female function. This sulfonylurea herbicide has a promising use as the gametocide for hybrid production in cruciferous plants.

  13. Identification of Genes Potentially Associated with the Fertility Instability of S-Type Cytoplasmic Male Sterility in Maize via Bulked Segregant RNA-Seq.

    Directory of Open Access Journals (Sweden)

    Aiguo Su

    Full Text Available S-type cytoplasmic male sterility (CMS-S is the largest group among the three major types of CMS in maize. CMS-S exhibits fertility instability as a partial fertility restoration in a specific nuclear genetic background, which impedes its commercial application in hybrid breeding programs. The fertility instability phenomenon of CMS-S is controlled by several minor quantitative trait locus (QTLs, but not the major nuclear fertility restorer (Rf3. However, the gene mapping of these minor QTLs and the molecular mechanism of the genetic modifications are still unclear. Using completely sterile and partially rescued plants of fertility instable line (FIL-B, we performed bulk segregant RNA-Seq and identified six potential associated genes in minor effect QTLs contributing to fertility instability. Analyses demonstrate that these potential associated genes may be involved in biological processes, such as floral organ differentiation and development regulation, energy metabolism and carbohydrates biosynthesis, which results in a partial anther exsertion and pollen fertility restoration in the partially rescued plants. The single nucleotide polymorphisms (SNPs identified in two potential associated genes were validated to be related to the fertility restoration phenotype by KASP marker assays. This novel knowledge contributes to the understanding of the molecular mechanism of the partial fertility restoration of CMS-S in maize and thus helps to guide the breeding programs.

  14. Sterilization System

    Science.gov (United States)

    1990-01-01

    Cox Sterile Products, Inc.'s Rapid Heat Transfer Sterilizer employs a heat exchange process that induces rapid air movement; the air becomes the heat transfer medium, maintaining a uniform temperature of 375 degrees Fahrenheit. It features pushbutton controls for three timing cycles for different instrument loads, a six-minute cycle for standard unpackaged instruments, eight minutes for certain specialized dental/medical instruments and 12 minutes for packaged instruments which can then be stored in a drawer in sterile condition. System will stay at 375 degrees all day. Continuous operation is not expensive because of the sterilizer's very low power requirements.

  15. Climatic factors and populational dynamics of Mahanarva posticata (Stal-1855) (Homoptera-Cercopidae) as a contribution to a possible regional implantation of the sterile male technique

    International Nuclear Information System (INIS)

    Oliveira, M.L. de

    1981-01-01

    A field study on the population dynamics of M. posticata (STAL, 1855) (Homoptera-Cercopidae) was carried out from 1971 to 1978 under the ecological conditions prevailing in the Litoral-Mata-Sul Zone of Pernambuco, Brazil. The results indicated that maximal infestation of the sugar cane crops by the insect generally occured in June and in July, and it was dependent on rainfall, temperature and relative humidity. The population density of adults was decreased markedly during the months of January, February and March. Technical and economical viability of the insect control by the male-sterilization-techniques through radiation was also demonstrated. The technique is to be used isolated or with other conventional procedures in the combat of froghopper infestations in the sugar cane growing in Pernambuco, Brazil. (Author) [pt

  16. Cytogenetics of Triatominae: III - A study on male sterility induced through hybridization of Triatoma sórdida and Triatoma pseudomaculata

    Directory of Open Access Journals (Sweden)

    Giorgio Schreiber

    1975-08-01

    Full Text Available Males from bilateral crosses between Triatoma sórdida and Triatoma pseudomaculata were unable to give offspring, as shown by subsequent backcrosses (BC between hybrid males and parental females. This kind of sterility indueed through interspecific hybridization seems to be due to lack of sperm migration from the bursa copulatrix to the spermateca, thus suggesting primarily failure on the part of hybrid males to produce and/or to incorporate male accessory secretions into the spermatophore bulb. Addicional proof that sterility induced in hybrid males is at the sperm level has been afforded by the spermatogenesis herein studied. The anomalous processes like; 1 prophases of spermatogonia with the chromosomes scattered in the cytoplasm, 2 first metaphases with unpaired tetrades, 3 spermatids differing in size and 4 spermatozoa of abnormal shape and generdlly of giant size, can be taken as an indicator of the degree of departure from the normal course of spermatogenesis.Os machos provenientes de cruzamentos bilaterais entre Triatoma sórdida e Triatoma pseudomaculata revelaram a incapacidade de produzir progênie, como se demonstra nos retrocruzamentos de machos híbridos com fêmeas das espécies paternas. Esta modalidade de esterilidade induzida através da hibridação interespecífica, parece ser devida à ausência de migração do esperma, determinada pela incapacidade dos híbridos machos produzirem a secreção opaca em suas glândulas acessórias e/ou incorporá-la à luz do espermatóforo. A prova adicional de que a incompatibilidade induzida em triatomíneos, através da hibridação inter específica, está no nível do esperma é fornecida pelo tipo anômalo de espermatogênese em híbridos aqui descrito, mostrando deste modo que: as prófases espermatogoniais têm os núcleos disruptos e os cromossomos espelhados no citoplasma. As primeiras metáfases meióticas têm as tétrades desemparelhadas. Os grupos de cromatídes assim obtidos

  17. Contraception Update: Sterilization.

    Science.gov (United States)

    Antell, Karen; Deshmukh, Prium; Brown, Elizabeth J

    2017-11-01

    Female sterilization procedures include postpartum partial salpingectomy via cesarean or minilaparotomy incision, interval laparoscopic procedures, or hysteroscopic placement of microinserts. Rates of failure and serious complications are low and comparable among the various methods. A hysteroscopic procedure requires a 3-month confirmatory hysterosalpingogram before it is considered effective for contraception. Hysteroscopic sterilization has been shown to be associated with a higher reoperation rate than laparoscopic procedures. For male sterilization, vasectomy is a noninvasive and highly effective method. Vasectomy is an outpatient procedure performed under local anesthesia. The procedure requires confirmation of azoospermia with a semen analysis 8 to 16 weeks after the procedure. Patients who are considering sterilization should be counseled about all the available options and the permanent nature of such procedures. Written permission from the American Academy of Family Physicians is required for reproduction of this material in whole or in part in any form or medium.

  18. Female Engineers: Their Career Socialization into a Male-Dominated Occupation.

    Science.gov (United States)

    Eden, Devorah

    1992-01-01

    Studies female engineers' characteristics, how they were socialized into engineering, and coping mechanisms for a male-dominated work world. Interviews with 29 women and 3 men suggest that women choose engineering because of the challenge, interest, and parental influence. Many female engineers experience gender discrimination and problems with…

  19. The effect of disease on the evolution of females and the genetic basis of sex in populations with cytoplasmic male sterility.

    Science.gov (United States)

    Miller, Ian; Bruns, Emily

    2016-02-10

    The evolution of separate males and females is an important evolutionary transition that has occurred multiple times in flowering plants. While empirical studies have stressed the potential importance of natural enemies and organismal interactions in the evolution of separate sexes, there has been no treatment of natural enemies in the theoretical literature. We investigated the effects of disease on the evolution of females in gynodioecious populations composed of females and hermaphrodites, where sex is determined by the interaction of cytoplasmic male sterility (CMS) and nuclear restorer genes. When females are significantly more resistant than hermaphrodites, disease drives an increase in the frequency of females and sex determination becomes nuclear, creating the pre-conditions for the evolution of separate males and females. However, when females are only moderately more resistant, disease drives changes in the frequency of CMS and restorer alleles, but has little effect on the frequency of females. We discuss our results in the context of the evolution of mating systems and cyto-nuclear epistasis. © 2016 The Author(s).

  20. 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

  1. Swarming and mating behavior of male Anopheles arabiensis Patton (Diptera: Culicidae) in an area of the Sterile Insect Technique Project in Dongola, northern Sudan.

    Science.gov (United States)

    Hassan, Mo'awia M; Zain, Hussam M; Basheer, Mohammed A; Elhaj, Hassab-Elrasoul F; El-Sayed, Badria B

    2014-04-01

    The problems facing the conventional mosquito control methods including resistance to insecticides have led to the development of alternative methods such as the Sterile Insect Technique (SIT) to suppress populations of the malaria vector Anopheles arabiensis in northern Sudan. This method entails the release of large numbers of irradiated males to compete against wild conspecifics for mating with virgin females in the field. The swarming and mating behaviors of this species were conducted at two field sites during the period 2009-2012 in Dongola, northern Sudan. Observations were made in the field sites and in a contained semi-field enclosure. In addition, participation of released irradiated-marked males in the swarms of wild mosquito was investigated. Swarms were observed on sunset in the vicinity of larval habitats around irrigation channel and stopped with the onset of the darkness about 21-25 min after the start. Swarms were observed above visual markers such as palm trees, bare ground, and manure. Several couples were observed leaving the swarms in copula in the direction of the sunlight. The majority of copulations were observed within 12-15 min of the start of swarming. Relatively low insemination rates (28%) of females collected from coupling pairs were observed. Irradiated-marked males were observed to join the natural swarms regularly, indicating their probable competitiveness with the other wild males. These findings enhance the feasibility of staging an SIT campaign against malaria vector in Northern State-Sudan. Copyright © 2013 International Atomic Energy Agency 2013. Published by Elsevier B.V. All rights reserved.

  2. 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

  3. The addition of the Eckhardts method of the conversion of maize hybrid on the male sterility background regarding the possibility of the late break of sterility of the mother component

    Directory of Open Access Journals (Sweden)

    Vančetović Jelena

    2006-01-01

    Full Text Available It is given a scheme of the conversion of the mother and father of a maize hybrid with three checking of the possibility of the late break of sterility of the mother component. Only hybrids with stable sterility are recommended for the practical use. The scheme is needed a 6 years, so researchers should be careful in choosing hybrids for conversion and the starting point for it.

  4. Sterile neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, J. [PRISMA Cluster of Excellence & Mainz Institute for Theoretical Physics, Johannes Gutenberg University, 55099 Mainz (Germany); Machado, P. A. N., E-mail: pedro.machado@uam.es [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); Maltoni, M. [Instituto de Física Teórica UAM/CSIC, Calle Nicolás Cabrera 13-15, Cantoblanco E-28049 Madrid (Spain); Schwetz, T. [Institute for Nuclear Physics, Karlsruhe Institute of Technology (KIT), Postfach 3640, 76021 Karlsruhe (Germany)

    2016-06-21

    We characterize statistically the indications of a presence of one or more light sterile neutrinos from MiniBooNE and LSND data, together with the reactor and gallium anomalies, in the global context. The compatibility of the aforementioned signals with null results from solar, atmospheric, reactor, and accelerator experiments is evaluated. We conclude that a severe tension is present in the global fit, and therefore the addition of eV-scale sterile neutrinos does not satisfactorily explain the anomalies.

  5. 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.

  6. Mouse autosomal homolog of DAZ, a candidate male sterility gene in humans, is expressed in male germ cells before and after puberty

    Energy Technology Data Exchange (ETDEWEB)

    Reijo, R.; Seligman, J.; Jaffe, T. [Massachusetts Institute of Technology, Cambridge, MA (United States)] [and others

    1996-07-15

    Deletion of the Azoospermia Factor (AZF) region of the human Y chromosome results in spermatogenic failure. While the identity of the critical missing gene has yet to be established, a strong candidate is the putative RNA-binding protein DAZ (Deleted in Azoospermia). Here we describe the mouse homolog of DAZ. Unlike human DAZ, which is Y-linked, in mouse the Dazh (DAZ homolog) gene maps to chromosome 17. Nonetheless, the predicted amino acid sequences of the gene products are quite similar, especially in their RNP/RRM (putative RNA-binding) domains, and both genes are transcribed predominantly in testes; the mouse gene is transcribed at a lower level in ovaries. Dazh transcripts were not detected in testes of mice that lack germ cells. In testes of wildtype mice, Dazh transcription is detectable 1 day after birth (when the only germ cells are prospermatogonia), increases steadily as spermatogonial stem cells appear, plateaus as the first wave of spermatogenic cells enters meiosis (10 days after birth), and is sustained at this level thereafter. This unique pattern of expression suggests the Dazh participates in differentiation, proliferation, or maintenance of germ cell founder populations before, during, and after the pubertal onset of spermatogenesis. Such functions could readily account for the diverse spermatogenic defects observed in human males with AZF deletion. 29 refs., 4 figs.

  7. 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

  8. A comparison of personality characteristics of male and female engineering students

    Science.gov (United States)

    Williams, Erin Beth

    The purpose of this study was to investigate differences between personality characteristics of female and male freshmen, engineering students. A secondary purpose was to ascertain whether personality characteristics of freshmen, engineering students were different from those of general collegiate students of the same sex. The Millon Index of Personality Styles (MIPS) was administered to a sample of 72 female and 86 male freshmen, engineering students at a private midwestern engineering institution. The MIPS college normative sample of 1,600 college students was used as a comparison group. A total of 24 personality characteristics were assessed in the domains of motivation aims, cognitive modes, and interpersonal behaviors. Four hypotheses, which dealt with comparisons of the engineering samples, were tested by way of discriminant analyses. Two hypotheses, which compared the engineering samples to the collegiate samples of the same sex, were tested by way of t-tests. All six hypotheses yielded significant differences across various personality variables. It was concluded that engineering students of both sexes were more similar than different in personality characteristics. It was also concluded that there were greater personality differences between freshmen male engineering students and male college students than there are between freshmen female engineering students and female college students.

  9. Voluntary sterilization in Britain.

    Science.gov (United States)

    Jackson, L N

    1968-01-01

    Only recently has the value and importance of sterilization as an effective method of birth control come to be widely recognized in Britian. Credit for this recognition is largely due to the initiative of Dr. C. P. Blacker, chairman of the Simon Population Trust. The Trust's sterilization project was conceived by him and, heralded by an article in The Lancet on 30 April 1966, was launched at a press conference in London in May of that year. Since then the Project has gone from strength to strength. It first function was to make known how voluntary sterilization can help to solve or prevent family problems and to facilitate its practice in Britian. The project has also been concerned to correct the erroneous belief, still held by a dwindling number of medical and law persons, that sterilization is against the law. A prerequisite was to enlist cooperative surgeons all over the country, whose names are now being sent on request to family doctors wishing to refer men for sterilization. The project is concerned mainly with male, rather than female, sterilization. The reason for this is that, when the relative simplicity of vasectomy as compared with tubal ligation is explained to them most couples choose vasectomy. Information about sterilization is supplied not only to applicants but also to university and hospital authorities, surgeons, health and welfare workers, family planning clinics. Forms of consent are provided for the couple concerned, and a follow-up inquiry is being conducted on a substantial scale among men who have been sterilized through the agency of the Project. Though this inquiry is far from complete, replies so far received indicate almost universal satisfaction with the results of the operation. Indeed, with the fear of unwanted pregnancies removed, many couples report that marital harmony is increased. It is known that at least 2000 men have already been sterilized through the mediation of this Project and, as family doctors become increasingly

  10. Characterization and classification of one new cytoplasmic male sterility (CMS) line based on morphological, cytological and molecular markers in non-heading Chinese cabbage (Brassica rapa L.).

    Science.gov (United States)

    Heng, Shuangping; Shi, Dianyi; Hu, Zhenhua; Huang, Tao; Li, Jinping; Liu, Liyan; Xia, Chunxiu; Yuan, Zhenzhen; Xu, Yuejin; Fu, Tingdong; Wan, Zhengjie

    2015-09-01

    A new non-heading Chinese cabbage CMS line M119A was characterized and specific molecular markers were developed to classify different CMS types. One new non-heading Chinese cabbage (Brassica rapa L.) cytoplasmic male sterile (CMS) line M119A was obtained by interspecific crosses between the recently discovered hau CMS line of Brassica juncea and B. rapa. Furthermore, the line was characterized and compared with other five isonuclear-alloplasmic CMS lines. The M119A line produced six stamens without pollen and only two stamen fused together in fewer flowers. Tissue section indicated that anther abortion in M119A may have occurred during differentiation of the archesporial cells without pollen sac. All the six CMS lines were grouped into three types based on the presence of three PCR fragments of 825, 465 and 772 bp amplified with different mitochondrial genes specific primers. The 825-bp fragment was amplified both in 09-10A and H201A using the specific primer pair P-orf224-atp6, and showed 100 % identity with the mitochondrial gene of pol CMS. The 465-bp fragment was amplified in 30A and 105A using the primer pair P-orf138 and shared 100 % identity with the mitochondrial gene of ogu CMS. The 772-bp fragment was amplified in M119A and H203A using the primer pair P-orf288 and showed 100 % identity with the mitochondrial gene of hau CMS. Therefore, these markers could efficiently distinguish different types of isonuclear-alloplasmic CMS lines of non-heading Chinese cabbage, which were useful for improving the efficiency of cross-breeding and heterosis utilization in cruciferous vegetables.

  11. Identification of the predominant nonrestoring allele for Owen-type cytoplasmic male sterility in sugar beet (Beta vulgarisL.): development of molecular markers for the maintainer genotype.

    Science.gov (United States)

    Moritani, Mari; Taguchi, Kazunori; Kitazaki, Kazuyoshi; Matsuhira, Hiroaki; Katsuyama, Takaya; Mikami, Tetsuo; Kubo, Tomohiko

    2013-06-01

    Hybrid seed production in sugar beet relies on cytoplasmic male sterility (CMS). As time-consuming and laborious test crosses with a CMS tester are necessary to identify maintainer lines, development of a marker-assisted selection method for the rf gene (the nonrestoring allele of restorer - of - fertility locus) is highly desirable for sugar-beet breeding. To develop such a method, we investigated genetic variation at the Rf1 locus, one of two Rf loci known in sugar beet. After Hin dIII-digestion, genomic DNAs from beet plants known to have a restoring Rf1 allele yielded a range of hybridization patterns on agarose gels, indicating that Rf1 is a multi-allelic locus. However, the hybridization patterns of 22 of 23 maintainer lines were indistinguishable. The nucleotide sequences of the rf1 coding regions of these 22 maintainer lines were found to be identical, confirming that the lines had the same rf1 allele. Two PCR markers were developed that targeted a downstream intergenic sequence and an intron of Rf1. The electrophoretic patterns of both markers indicated multiple Rf1 alleles, one of which, named the dd(L) type, was associated with the maintainer genotype. To test the validity of marker-assisted selection, 147 sugar beet plants were genotyped using these markers. Additionally, the 147 sugar beet plants were crossed with CMS plants to determine whether they possessed the maintainer genotype. Analysis of 5038 F1 offspring showed that 53 % of the dd(L) plants, but none of the plants with other alleles, had the maintainer genotype. Thus, selection for the dd(L) type considerably enriched the proportion of plants with the maintainer genotype.

  12. Ability of Rf5 and Rf6 to Restore Fertility of Chinsurah Boro II-type Cytoplasmic Male Sterile Oryza Sativa (ssp. Japonica) Lines.

    Science.gov (United States)

    Zhang, Honggen; Che, Jianlan; Ge, Yongshen; Pei, Yan; Zhang, Lijia; Liu, Qiaoquan; Gu, Minghong; Tang, Shuzhu

    2017-12-01

    Three-line Oryza sativa (ssp. japonica) hybrids have been developed mainly using Chinsurah Boro II (BT)-type cytoplasmic male sterility (CMS). The Rf1 gene restores the fertility of BT-type CMS lines, and is the only fertility restorer gene (Rf) that has been used to produce three-line japonica hybrids. Using more Rf genes to breed BT-type restorer lines may broaden the genetic diversity of the restorer lines, and represents a viable approach to improve the heterosis level of BT-type japonica hybrids. We identified two major Rf genes from '93-11' that are involved in restoring the fertility of BT-type CMS plants. These genes were identified from resequenced chromosome segment substitution lines derived from a cross between the japonica variety 'Nipponbare' and the indica variety '93-11'. Molecular mapping results revealed that these genes were Rf5 and Rf6, which are the Rf genes that restore fertility to Honglian-type CMS lines. The BT-type F 1 hybrids with either Rf5 or Rf6 exhibited normal seed setting rates, but F 1 plants carrying Rf6 showed more stable seed setting rates than those of plants carrying Rf5 under heat-stress conditions. Furthermore, the seed setting rates of F 1 hybrids carrying both Rf5 and Rf6 were more stable than that of F 1 plants carrying only one Rf gene. Rf6 is an important genetic resource for the breeding of BT-type japonica restorer lines. Our findings may be useful for breeders interested in developing BT-type japonica hybrids.

  13. The roles played by mitochondrial DNA and nuclear genes in reversion to fertility in S-Type male-sterile maize. Progress report, April 1, 1985--March 31, 1989

    Energy Technology Data Exchange (ETDEWEB)

    Laughnan, J.R.

    1995-03-01

    This is a progress report/renewal request for work of the roles played by mitochondrial DNA and nuclear genes in reversion to fertility in s-type male sterile maize. Information is included for the following major catagories of research on this project: molecular basis for nuclear reversion; molecular characterization of cytoplasmic revertants; nuclear control over cytoplasmic reversion and over replication of S1 and S2; developmental studies; transposition of nuclear restorer elements.

  14. Explaining Academic Success in Engineering Degree Programs : Do Female and Male Students Differ?

    NARCIS (Netherlands)

    Kamphorst, Jan C.; Hofman, W.H. Adriaan; Jansen, Ellen P.W.A.; Terlouw, Cees

    2015-01-01

    Background In Dutch engineering education, female students outperform male students. Using an interactionalist framework, this study explores factors that contribute to this gender-based difference. Purpose This study aims to answer two questions: Do female and male students differ in background

  15. An unedited 1.1 kb mitochondrial orfB gene transcript in the Wild Abortive Cytoplasmic Male Sterility (WA-CMS system of Oryza sativa L. subsp. indica

    Directory of Open Access Journals (Sweden)

    Maiti Mrinal K

    2010-03-01

    Full Text Available Abstract Background The application of hybrid rice technology has significantly increased global rice production during the last three decades. Approximately 90% of the commercially cultivated rice hybrids have been derived through three-line breeding involving the use of WA-CMS lines. It is believed that during the 21st century, hybrid rice technology will make significant contributions to ensure global food security. This study examined the poorly understood molecular basis of the WA-CMS system in rice. Results RFLPs were detected for atp6 and orfB genes in sterile and fertile rice lines, with one copy of each in the mt-genome. The RNA profile was identical in both lines for atp6, but an additional longer orfB transcript was identified in sterile lines. 5' RACE analysis of the long orfB transcript revealed it was 370 bp longer than the normal transcript, with no indication it was chimeric when compared to the genomic DNA sequence. cDNA clones of the longer orfB transcript in sterile lines were sequenced and the transcript was determined unedited. Sterile lines were crossed with the restorer and maintainer lines, and fertile and sterile F1 hybrids were respectively generated. Both hybrids contained two types of orfB transcripts. However, the long transcript underwent editing in the fertile F1 hybrids and remained unedited in the sterile lines. Additionally, the editing of the 1.1 kb orfB transcript co-segregated with fertility restoring alleles in a segregating population of F2 progeny; and the presence of unedited long orfB transcripts was detected in the sterile plants from the F2 segregating population. Conclusion This study helped to assign plausible operative factors responsible for male-sterility in the WA cytoplasm of rice. A new point of departure to dissect the mechanisms governing the CMS-WA system in rice has been identified, which can be applied to further harness the opportunities afforded by hybrid vigor in rice.

  16. Use of the sterile male technique as an adjunct to insecticidal and physical methods for stable fly control on the island of St. Croix, U.S.V.I

    International Nuclear Information System (INIS)

    Patterson, R.S.; Labrecque, G.C.

    1980-01-01

    A three-year feasibility study was conducted on the island of St. Croix, U.S.V.I., on the use of the sterile male technique as an adjunct to insecticidal and physical measures to control the stable fly, Stomoxys calcitrans L. The native stable fly population cycled in relation to moisture; it was the highest during the rainy season in the autumn (1.9x10 6 ) then gradually declined to a low point (0.7x10 5 ) during the summer in the dry season. The releases were carried out with an indigenous strain of flies reared on the island. The adult flies (24-28-h old) were exposed to 2 kR of gamma irradiation in a cobalt source. This treatment plus marking reduced the competitiveness by about 15%. The sterile flies were released in lots of 4000 at prearranged points throughout the island. Approximately 1x10 5 sterile males/day for 18 months were released at 2 km intervals over the 218 km 2 island. This reduced the native population by about 50%. On selected farms where insecticide or sterile males could not be released, the fly pupal parasite, Spalangia endius Walker, was released. Sanitation and cleanup of breeding habitats were recommended to all farmers, but were practised by very few. When all control techniques were in practice, the native stable fly population was reduced by 99.9%. A few fertile flies were found during the last six months of this experiment. These came from isolated breeding sites, flies immigrating from other islands about 40 km away or were introduced with imported livestock and/or pets. During this period no larval breeding was observed indicating that immigration was probably the main cause of the fertile flies on the island. (author)

  17. MS26/CYP704B is required for anther and pollen wall development in bread wheat (Triticum aestivum L. and combining mutations in all three homeologs causes male sterility.

    Directory of Open Access Journals (Sweden)

    Manjit Singh

    Full Text Available Development of anthers and pollen represents an important aspect of the life cycle in flowering plants. Genes contributing to anther and pollen development have been widely studied in many plant species. Ms26/CYP704B genes play an important role in pollen development through biosynthesis of sporopollenin for pollen exine formation. To investigate the role of Ms26/CYP704B genes in anther and pollen development of bread wheat, mutations in the A-, B-, and D-homeologs of the putative Ms26/CYP704B gene were analyzed. Single and double homozygous mutants in any of the homeologs did not affect pollen development and male fertility. Triple homozygous mutants resulted in completely male sterile plants that were defective in pollen and anther development. Additionally, double homozygous-single heterozygous mutants were also male sterile although with varying levels of residual fertility. The fertility of these triple mutants was dependent upon the homeolog contributing the wild-type allele. Two heterologous Ms26/CYP704B genes, when transformed into a triple homozygous mutant background, completely restored male fertility, whereas a single gene was unable to restore fertility. Functional analysis of Ms26/CYP704B furthers the understanding of male fertility genes which can be utilized for the development of novel hybrid seed production systems in wheat.

  18. Cytoplasmic Male Sterility of Rice with Boro II Cytoplasm Is Caused by a Cytotoxic Peptide and Is Restored by Two Related PPR Motif Genes via Distinct Modes of mRNA Silencing[W

    Science.gov (United States)

    Wang, Zhonghua; Zou, Yanjiao; Li, Xiaoyu; Zhang, Qunyu; Chen, Letian; Wu, Hao; Su, Dihua; Chen, Yuanling; Guo, Jingxin; Luo, Da; Long, Yunming; Zhong, Yang; Liu, Yao-Guang

    2006-01-01

    Cytoplasmic male sterility (CMS) and nucleus-controlled fertility restoration are widespread plant reproductive features that provide useful tools to exploit heterosis in crops. However, the molecular mechanism underlying this kind of cytoplasmic–nuclear interaction remains unclear. Here, we show in rice (Oryza sativa) with Boro II cytoplasm that an abnormal mitochondrial open reading frame, orf79, is cotranscribed with a duplicated atp6 (B-atp6) gene and encodes a cytotoxic peptide. Expression of orf79 in CMS lines and transgenic rice plants caused gametophytic male sterility. Immunoblot analysis showed that the ORF79 protein accumulates specifically in microspores. Two fertility restorer genes, Rf1a and Rf1b, were identified at the classical locus Rf-1 as members of a multigene cluster that encode pentatricopeptide repeat proteins. RF1A and RF1B are both targeted to mitochondria and can restore male fertility by blocking ORF79 production via endonucleolytic cleavage (RF1A) or degradation (RF1B) of dicistronic B-atp6/orf79 mRNA. In the presence of both restorers, RF1A was epistatic over RF1B in the mRNA processing. We have also shown that RF1A plays an additional role in promoting the editing of atp6 mRNAs, independent of its cleavage function. PMID:16489123

  19. Cytoplasmic male sterility of rice with boro II cytoplasm is caused by a cytotoxic peptide and is restored by two related PPR motif genes via distinct modes of mRNA silencing.

    Science.gov (United States)

    Wang, Zhonghua; Zou, Yanjiao; Li, Xiaoyu; Zhang, Qunyu; Chen, Letian; Wu, Hao; Su, Dihua; Chen, Yuanling; Guo, Jingxin; Luo, Da; Long, Yunming; Zhong, Yang; Liu, Yao-Guang

    2006-03-01

    Cytoplasmic male sterility (CMS) and nucleus-controlled fertility restoration are widespread plant reproductive features that provide useful tools to exploit heterosis in crops. However, the molecular mechanism underlying this kind of cytoplasmic-nuclear interaction remains unclear. Here, we show in rice (Oryza sativa) with Boro II cytoplasm that an abnormal mitochondrial open reading frame, orf79, is cotranscribed with a duplicated atp6 (B-atp6) gene and encodes a cytotoxic peptide. Expression of orf79 in CMS lines and transgenic rice plants caused gametophytic male sterility. Immunoblot analysis showed that the ORF79 protein accumulates specifically in microspores. Two fertility restorer genes, Rf1a and Rf1b, were identified at the classical locus Rf-1 as members of a multigene cluster that encode pentatricopeptide repeat proteins. RF1A and RF1B are both targeted to mitochondria and can restore male fertility by blocking ORF79 production via endonucleolytic cleavage (RF1A) or degradation (RF1B) of dicistronic B-atp6/orf79 mRNA. In the presence of both restorers, RF1A was epistatic over RF1B in the mRNA processing. We have also shown that RF1A plays an additional role in promoting the editing of atp6 mRNAs, independent of its cleavage function.

  20. Digital Games, Gender and Learning in Engineering: Do Females Benefit as Much as Males?

    Science.gov (United States)

    Joiner, Richard; Iacovides, Jo; Owen, Martin; Gavin, Carl; Clibbery, Stephen; Darling, Jos; Drew, Ben

    2011-01-01

    The aim of this paper was to explore whether there is a gender difference in the beneficial effects of Racing Academy, which is a video game used to support undergraduate students learning of Mechanical Engineering. One hundred and thirty-eight undergraduate students (15 females and 123 males) participated in the study. The students completed a…

  1. Female and male Hispanic students majoring in science or engineering: Their stories describing their educational journeys

    Science.gov (United States)

    Brown, Susan Wightman

    National statistics clearly demonstrate an underrepresentation of minorities in the fields of science and engineering. Blacks, Hispanics, American Indians, and Asians do not typically choose science or engineering as their college major; therefore, there is a very small representation of these minorities in the science and engineering labor force. The decision not to major in science and engineering may begin as soon as the child can begin to recognize role models in the media. News stories, magazine articles, television programs, teachers, parents, administrators, and other agencies have painted the picture of a scientist or engineer as being dominantly a White male. Schools have continued society's portrayal by using curriculum, textbooks, role models, instructional strategies, and counseling that continues to encourage the White male to succeed in science and engineering, but discourages the minority students, male and female, from succeeding in these fields. In this qualitative study, 22 Hispanic students, 12 female and 10 male, who are majoring in science or engineering, were interviewed using Seidman's in-depth interviewing technique. These students were shadowed in their college science or engineering classes; their high school and college transcripts were analyzed; and, a focus group was brought together at the end of the interviewing process in order to allow interaction between the participants. The goal was to explore the educational journeys of the 22 Hispanic students. What made a difference in the journeys of these 22 students so that they could succeed in majors that have historically discouraged minority students? Seven themes emerged: family support, honors program, challenging and interactive curriculum, college preparation in high school courses, caring and kind teachers, small class size, and small communities. Gender comparison of the educational journeys documents these differences between the females and males: college preparation, mentoring

  2. Genetic expression of induced rice sterility under alien-cytoplasm

    International Nuclear Information System (INIS)

    Wang Naiyuan; Cai Zhijun; Liang Kangjing; Li Yu

    2005-01-01

    Rice restorer lines were treated with 60 Co γ-ray and 4 male sterile mutants obtained with the fertility of controlled by 4 non-allelic recessive genes, respectively. Sixty combinations were made by using male sterile plants/fertile plants as male parents, and 15 different cytoplasmic substitution lines of the same cell nucleus as female parents. The result showed that F 1 spikelets were normal and fertile, and different numbers of male sterile plants were segregated in F 2 . Complete fertility genotype was not found among interactions between induced male sterile genes and alien-cytoplasms. (authors)

  3. The use of radiation induced sterility for the control of the codling moth. Part of a coordinated programme on the use of the sterile male technique for the control of lepidopterous insects attacking fruit and forest trees

    International Nuclear Information System (INIS)

    Jermy, T.

    1977-12-01

    Studies were conducted from 1973 - 1977 in Hungary to obtain background information necessary for the implementation of sterile insect techniques (SIT) and pest management systems. The flight of the codling moth (CM), monitored by sex-pheromone traps, lasted from May to September. The two peaks (corresponding to the two generations per year) and the break between the two flights appeared blurred, i.e. control measures should be carried out nearly continuously during the whole season. The number of CM pairs was estimated by the release-recapture method as 100 to 500 per ha in mid-summer in an untreated orchard. Such naturally occurring low population levels could help initiating successful SIT against the CM even in not thoroughly treated apple stands. Mixed house gardens containing abandoned host trees have to be considered in Hungary as the main reservoir of the supposed ''semiwild type'' CM. Oak forests proved to harbour autonomous ''wild type'' CM populations on wild apple and sorb trees. The chemically well treated apple orchards have generally very low ''farm type'' CM populations. Natural occurrence of the CM granulosis virus in larvae developing in wild apples has been found. Transmission of the virus in laboratory rearings by the mite Tyrophagus putrescentiae was detected. Spraying with virus suspensions fully protected apples against the CM; however, no spread of the virus to neighbouring untreated trees was observed. Surveys for other major insect pests (Lepidoptera, aphids and scales) of apples were also made and the high population levels of several species in the untreated apple stands have been found indicating that (1) natural control generally cannot reduce these populations to an economically acceptable level, and (2) the SIT against the CM must be combined with chemical treatments or with selective methods against these species. Based on a theoretical analysis of economic aspects of the SIT for codling moth control, it was found that in Hungary

  4. Genomic networks of hybrid sterility.

    Directory of Open Access Journals (Sweden)

    Leslie M Turner

    2014-02-01

    Full Text Available 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

  5. Digital Games, Gender and Learning in Engineering: Do Females Benefit as Much as Males?

    Science.gov (United States)

    Joiner, Richard; Iacovides, Jo; Owen, Martin; Gavin, Carl; Clibbery, Stephen; Darling, Jos; Drew, Ben

    2011-04-01

    The aim of this paper was to explore whether there is a gender difference in the beneficial effects of Racing Academy, which is a video game used to support undergraduate students learning of Mechanical Engineering. One hundred and thirty-eight undergraduate students (15 females and 123 males) participated in the study. The students completed a pre-test a week before they started using Racing Academy. The pre-test consisted of a test of students' knowledge of engineering, and a measure of students' motivation towards studying engineering. A week after using Racing Academy the students completed a post-test which was identical to the pre-test, except it also included a measure of how frequently they used Racing Academy and how motivating the students found playing Racing Academy. We found that after playing Racing Academy the students learnt more about engineering and there was no gender difference in the beneficial effect of Racing Academy, however there is some evidence that, female students found Racing Academy more motivating than male students. The implications for the use and design of video games for supporting learning for both males and females are discussed.

  6. Interval Female Sterilization.

    Science.gov (United States)

    Stuart, Gretchen S; Ramesh, Shanthi S

    2018-01-01

    Female sterilization is relied on by nearly one in three women aged 35-44 years in the United States. Sterilization procedures are among the most common procedures that obstetrician-gynecologists perform. The most frequent sterilization procedures include postpartum tubal ligation, laparoscopic tubal disruption or salpingectomy, and hysteroscopic tubal occlusion. The informed consent process for sterilization is crucial and requires shared decision-making between the patient and the health care provider. Counseling should include the specific risks and benefits of the specific surgical approaches. Additionally, women should be counseled on the alternatives to sterilization, including intrauterine contraceptives and subdermal contraceptive implants. Complications, including unplanned pregnancy after successful female sterilization, are rare. The objectives of this Clinical Expert Series are to describe the epidemiology of female sterilization, access to postpartum sterilization, advances in interval sterilization techniques, and clinical considerations in caring for women requesting sterilization.

  7. Transgenic technologies to induce sterility

    Directory of Open Access Journals (Sweden)

    Wimmer Ernst A

    2009-11-01

    Full Text Available Abstract The last few years have witnessed a considerable expansion in the number of tools available to perform molecular and genetic studies on the genome of Anopheles mosquitoes, the vectors of human malaria. As a consequence, knowledge of aspects of the biology of mosquitoes, such as immunity, reproduction and behaviour, that are relevant to their ability to transmit disease is rapidly increasing, and could be translated into concrete benefits for malaria control strategies. Amongst the most important scientific advances, the development of transgenic technologies for Anopheles mosquitoes provides a crucial opportunity to improve current vector control measures or design novel ones. In particular, the use of genetic modification of the mosquito genome could provide for a more effective deployment of the sterile insect technique (SIT against vector populations in the field. Currently, SIT relies on the release of radiation sterilized males, which compete with wild males for mating with wild females. The induction of sterility in males through the genetic manipulation of the mosquito genome, already achieved in a number of other insect species, could eliminate the need for radiation and increase the efficiency of SIT-based strategies. This paper provides an overview of the mechanisms already in use for inducing sterility by transgenesis in Drosophila and other insects, and speculates on possible ways to apply similar approaches to Anopheles mosquitoes.

  8. Sterilization of mentally retarded persons.

    Science.gov (United States)

    Van der Merwe, J V; Roux, J P

    1987-08-01

    South Africa's Abortion and Sterilization Act No 2 (1975) authorizes sterilization for severely retarded women provided the procedure is performed in a state hospital, certified by 2 medical practitioners (1 a psychiatrist), and the parent or guardian gives informed consent. Since 1975, 152 sterilizations (140 female, 12 male) have been performed under the provisions of this Act at Pretoria's H F Verwoerd Hospital. 92% of the patients were under 20 years of age. The majority were classified as profoundly or severely retarded (74) or moderately severely retarded (68). There were 20 patients with Down's syndrome and 22 with cerebral palsy. Hysterectomy was the method of choice in the 109 women in whom menstrual hygiene was a pertinent factor; the remaining 31 women were sterilized by tubal ligation. 98% of the parents or guardians of hysterectomy acceptors surveyed were satisfied with their decision and its outcome. Several indicated their daughter was more calm, cooperative, productive, and less irritable once relieved of her menstrual periods. A multidisciplinary team approach to the decision making process and the individualization of each case are essential to protect the rights of the mentally retarded. Factors such as the psychological trauma likely to result from pregnancy and childbirth, an inability to use contraception, and unsuitability to rear a child must be demonstrated. To ensure that legislation pertaining to the sterilization of the mentally retarded does not lead to abuse, inputs from the mental health professions are required.

  9. Conditional sterility in plants

    Science.gov (United States)

    Meagher, Richard B.; McKinney, Elizabeth; Kim, Tehryung

    2010-02-23

    The present disclosure provides methods, recombinant DNA molecules, recombinant host cells containing the DNA molecules, and transgenic plant cells, plant tissue and plants which contain and express at least one antisense or interference RNA specific for a thiamine biosynthetic coding sequence or a thiamine binding protein or a thiamine-degrading protein, wherein the RNA or thiamine binding protein is expressed under the regulatory control of a transcription regulatory sequence which directs expression in male and/or female reproductive tissue. These transgenic plants are conditionally sterile; i.e., they are fertile only in the presence of exogenous thiamine. Such plants are especially appropriate for use in the seed industry or in the environment, for example, for use in revegetation of contaminated soils or phytoremediation, especially when those transgenic plants also contain and express one or more chimeric genes which confer resistance to contaminants.

  10. 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'

  11. Investigations on the use of the sterile male technique for the control of codling moth in an integrated pest control system

    International Nuclear Information System (INIS)

    Russ, K.

    1978-10-01

    The diapause of the codling moth, Laspeyresia pomonella L., was studied in relation to various altitudes of origin. Altitudes of 350 m and 1300 m above sea level showed that low-altitude moths had a longer diapause. Altitude appears to affect the duration of larval diapause. Biological control by virus-induced granulosis was investigated, using 3 to 4 applications of the virus per tree per season, at the rate of 2x10 11 to 9x10 11 virus capsules per application. Codling moth infestation was reduced by 74.2% to 88.2%. Trichomma enecator and Ascogaster quadridentatus Wesm., both parasites of the codling moth, were both colonized in the laboratory, and population dynamics are being studied. Copulatory behaviour in the males of A. quadridentatus is elicited primarily by pheromones produced by the female. Males emit some sounds which appear primarily intended to convey territorial rights to other males. The frequencies produced by males and by females differ. Codling moth odours stimulate females to oviposit. The effect of pesticides on parasitation is being studied. Details of a planned mass-rearing facility for lepidopteran and other pests are given

  12. Guidelines for pre-sterilization counseling.

    Science.gov (United States)

    1996-09-01

    The following guidelines for pre-sterilization counseling have been adopted by the Association for Voluntary Surgical Contraception: 1) emphasize that sterilization is permanent; 2) involve both partners in the decision making and present male sterilization as a viable option; 3) even if sterilization is requested, also present the range of long-term reversible methods available; 4) inform the client of failure rates associated with female sterilization and the associated risk of ectopic pregnancy; 5) emphasize that sterilization provides no protection against sexually transmitted diseases, including human immunodeficiency virus; 6) screen candidates for risk factors of post-sterilization regret, including young age and sterilization at the time of abortion or delivery; 7) fully explain the surgical procedure, preoperative instructions, surgical site, timing of the procedure, type of anesthesia, surgical risks, and length of recovery; 8) describe the possibility of unrelated changes in menstruation; 9) answer all questions; 10) discuss the positive effects on sexuality once concerns about unwanted pregnancy are removed; and 11) provide printed educational materials that the couple can review privately.

  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. Bringing men to the table: sterilization can be for him or for her.

    Science.gov (United States)

    Shih, Grace; Zhang, Ying; Bukowski, Kyle; Chen, Angela

    2014-12-01

    Sterilization, male and female combined, is the most common use of contraception in the United States. Despite the lower risk, higher cost-efficacy, and high efficacy of vasectomy compared with female sterilization, more US women rely on female sterilization than male sterilization. Reasons for low use of vasectomy include lack of knowledge and misconceptions about the procedure, lack of access, provider bias, and patient preferences. This article will provide a basic overview of male and female sterilization, an exploration of vasectomy barriers, and ways obstetrician-gynecologists can increase vasectomy uptake including regular recommendation of vasectomy to patients in long-term committed relationships considering sterilization.

  15. Sterile neutrinos in cosmology

    Science.gov (United States)

    Abazajian, Kevork N.

    2017-11-01

    Sterile neutrinos are natural extensions to the standard model of particle physics in neutrino mass generation mechanisms. If they are relatively light, less than approximately 10 keV, they can alter cosmology significantly, from the early Universe to the matter and radiation energy density today. Here, we review the cosmological role such light sterile neutrinos can play from the early Universe, including production of keV-scale sterile neutrinos as dark matter candidates, and dynamics of light eV-scale sterile neutrinos during the weakly-coupled active neutrino era. We review proposed signatures of light sterile neutrinos in cosmic microwave background and large scale structure data. We also discuss keV-scale sterile neutrino dark matter decay signatures in X-ray observations, including recent candidate ∼3.5 keV X-ray line detections consistent with the decay of a ∼7 keV sterile neutrino dark matter particle.

  16. Genotipagem de polimorfismos associados com sistemas de macho-esterilidade em acessos de cebola adaptados ao Brasil Genotyping of polymorphisms associated with male-sterility systems in onion accessions adapted for cultivation in Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Francisco Ragassi

    2012-09-01

    Full Text Available A produção em escala comercial de sementes híbridas de cebola (Allium cepa tem sido conduzida com o emprego de dois sistemas de macho-esterilidade do tipo genética-citoplasmática (CMS-S e CMS-T em associação ao citoplasma normal (macho-fértil. No entanto, a análise molecular desses diferentes tipos citoplasmáticos ainda não está disponível para um grande número de acessos de cebola adaptados para cultivo em regiões tropicais. Além de adaptação às condições edafoclimáticas do Brasil, muitos desses acessos apresentam tolerância a doenças, sendo de potencial valor como genitores de híbridos. O presente trabalho visou identificar os tipos citoplasmáticos de acessos de cebola de diferentes grupos morfoagronômicos de interesse para o melhoramento genético no Brasil, usando a reação da polimerase em cadeia (PCR com 'primers' específicos para regiões polimórficas do genoma mitocondrial de cebola. Foi observada, nos 66 acessos amostrados, a presença dos três principais tipos de citoplasma descritos para cebola (S, N e T. Foi constatada maior frequência do citoplasma S (56% seguido do citoplasma T (25,8%. Em 18,2% das amostras, foi encontrado exclusivamente o citoplasma N. Essa caracterização pode ser útil para guiar a escolha de materiais genéticos dentro dos programas de melhoramento com objetivo de desenvolver cultivares híbridas adaptadas às condições tropicais.The synthesis of onion (Allium cepa hybrids relies upon the use of two genetic-cytoplasmic male-sterility systems, CMS-S and CMS-T, in association to the normal male-fertile (N cytoplasm. However, the molecular phenotyping of male-sterility-inducing and normal cytoplasms of many onion accessions adapted for cultivation under tropical conditions is not available. Some of these accessions were reported as presenting tolerance to diseases and adaptation to tropical and subtropical regions. Therefore, these accessions are potential sources of parental

  17. Women Break an Engineering Barrier: While Other Engineering Disciplines Stumble, BME Represents a Success Story in Attracting American Women to a Male-Dominated Field.

    Science.gov (United States)

    Gutierrez, Claudia; Paulosky, Meaghan; Aguinaldo, Angeline; Gerhart, Jackie

    2017-01-01

    While the field of engineering as a whole is largely male-dominated, biomedical engineering (BME) is one area poised to overturn this trend. Women in the United States were awarded only 20% of all engineering B.S. degrees in 2015; in BME, however, 40.9% of the degree recipients were women. This stands in stark contrast to the more traditional fields of mechanical and electrical engineering, where women were awarded just 13.2% and 12.5% of B.S. degrees, respectively. This trend toward more female participation in BME continues at both the M.S. and Ph.D. degree levels. In fact, in 2015, BME had the highest percentage of female engineering M.S. degree recipients in the United States of all engineering disciplines, according to the American Society for Engineering Education (Figure 1).

  18. Sex differences in gender characteristics of Australian nurses and male engineers: a comparative cross-sectional survey.

    Science.gov (United States)

    J Fisher, Murray

    2011-08-01

    There continue to be assumptions within the nursing literature that nursing is synonymous with a feminine sex role identity. A comparative cross-sectional survey consisting of the Bem Sex Role Inventory and the Australian sex role scale was used to determine sex difference in gender characteristics of Australian nurses and with male engineers. A statistically significant difference in femininity was found between all the samples (F((2,908)) = 20.24, p relationships between the samples and expressive orientation (t = 27.67) and self display (t = 12.42). Whilst differences in expressive characteristics were found between male and female nurses, a similar difference was found between male nurses and male engineers, supporting the notion that male nurses perceive themselves as having feminine characteristics essentially required for nursing.

  19. ACOG Practice bulletin no. 133: benefits and risks of sterilization.

    Science.gov (United States)

    2013-02-01

    Female and male sterilization are both safe and effective methods of permanent contraception used by more than 220 million couples worldwide . Approximately 600,000 tubal occlusions and 200,000 vasectomies are performed in the United States annually . For women seeking permanent contraception, sterilization obviates the need for user-dependent contraception throughout their reproductive years and provides an excellent alternative for those with medical contraindications to reversible methods. The purpose of this document is to review the evidence for the safety and effectiveness of female sterilization in comparison with male sterilization and other forms of contraception.

  20. Committee Opinion No. 695: Sterilization of Women: Ethical Issues and Considerations.

    Science.gov (United States)

    2017-04-01

    Sterilization is the most common method of contraception among married couples, with nearly twice as many couples choosing female partner sterilization over male sterilization. Although sterilization is among the most straightforward surgical procedures an obstetrician-gynecologist performs, it is enormously complex when considered from a historical, sociological, or ethical perspective. Sterilization practices have embodied a problematic tension, in which some women who desired fertility were sterilized without their knowledge or consent, and other women who wanted sterilization to limit their family size lacked access to it. An ethical approach to the provision of sterilization must, therefore, promote access for women who wish to use sterilization as a method of contraception, but at the same time safeguard against coercive or otherwise unjust uses. This Committee Opinion reviews ethical issues related to the sterilization of women and outlines an approach to providing permanent sterilization within a reproductive justice framework that recognizes that all women have a right to pursue and to prevent pregnancy.

  1. Committee Opinion No 695 Summary: Sterilization of Women: Ethical Issues and Considerations.

    Science.gov (United States)

    2017-04-01

    Sterilization is the most common method of contraception among married couples, with nearly twice as many couples choosing female partner sterilization over male sterilization. Although sterilization is among the most straightforward surgical procedures an obstetrician-gynecologist performs, it is enormously complex when considered from a historical, sociological, or ethical perspective. Sterilization practices have embodied a problematic tension, in which some women who desired fertility were sterilized without their knowledge or consent, and other women who wanted sterilization to limit their family size lacked access to it. An ethical approach to the provision of sterilization must, therefore, promote access for women who wish to use sterilization as a method of contraception, but at the same time safeguard against coercive or otherwise unjust uses. This Committee Opinion reviews ethical issues related to the sterilization of women and outlines an approach to providing permanent sterilization within a reproductive justice framework that recognizes that all women have a right to pursue and to prevent pregnancy.

  2. [Regret of female sterilization].

    Science.gov (United States)

    Öhman, Malin Charlotta; Andersen, Lars Franch

    2015-11-16

    Regret of sterilization is inversely correlated to age at the time of sterilization. The minimum age for legal sterilization in Denmark has recently been lowered to 18 years. In Denmark surgical refertilization has almost completely been replaced by in vitro fertilization (IVF). In recent literature pregnancy results after surgical refertilization are easily comparable to IVF. Refertilization may in some cases be advantageous to IVF treatment. Women requesting reversal of sterilization should be offered individualized evaluation and differentiated treatment. It is recommended that surgical refertilization is performed at very few centres.

  3. Conservation of Male Sterility 2 function during spore and pollen wall development supports an evolutionarily early recruitment of a core component in the sporopollenin biosynthetic pathway.

    Science.gov (United States)

    Wallace, Simon; Chater, Caspar C; Kamisugi, Yasuko; Cuming, Andrew C; Wellman, Charles H; Beerling, David J; Fleming, Andrew J

    2015-01-01

    The early evolution of plants required the acquisition of a number of key adaptations to overcome physiological difficulties associated with survival on land. One of these was a tough sporopollenin wall that enclosed reproductive propagules and provided protection from desiccation and UV-B radiation. All land plants possess such walled spores (or their derived homologue, pollen). We took a reverse genetics approach, consisting of knock-out and complementation experiments to test the functional conservation of the sporopollenin-associated gene MALE STERILTY 2 (which is essential for pollen wall development in Arabidopsis thaliana) in the bryophyte Physcomitrella patens. Knock-outs of a putative moss homologue of the A. thaliana MS2 gene, which is highly expressed in the moss sporophyte, led to spores with highly defective walls comparable to that observed in the A. thaliana ms2 mutant, and extremely compromised germination. Conversely, the moss MS2 gene could not rescue the A. thaliana ms2 phenotype. The results presented here suggest that a core component of the biochemical and developmental pathway required for angiosperm pollen wall development was recruited early in land plant evolution but the continued increase in pollen wall complexity observed in angiosperms has been accompanied by divergence in MS2 gene function. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  4. Enhanced stability of Mcl1, a prosurvival Bcl2 relative, blunts stress-induced apoptosis, causes male sterility, and promotes tumorigenesis.

    Science.gov (United States)

    Okamoto, Toru; Coultas, Leigh; Metcalf, Donald; van Delft, Mark F; Glaser, Stefan P; Takiguchi, Megumi; Strasser, Andreas; Bouillet, Philippe; Adams, Jerry M; Huang, David C S

    2014-01-07

    The B-cell CLL/lymphoma 2 (Bcl2) relative Myeloid cell leukemia sequence 1 (Mcl1) is essential for cell survival during development and for tissue homeostasis throughout life. Unlike Bcl2, Mcl1 turns over rapidly, but the physiological significance of its turnover has been unclear. We have gained insight into the roles of Mcl1 turnover in vivo by analyzing mice harboring a modified allele of Mcl1 that serendipitously proved to encode an abnormally stabilized form of Mcl1 due to a 13-aa N-terminal extension. Although the mice developed normally and appeared unremarkable, the homozygous males unexpectedly proved infertile due to defective spermatogenesis, which was evoked by enhanced Mcl1 prosurvival activity. Under unstressed conditions, the modified Mcl1 is present at levels comparable to the native protein, but it is markedly stabilized in cells subjected to stresses, such as protein synthesis inhibition or UV irradiation. Strikingly, the modified Mcl1 allele could genetically complement the loss of Bcl2, because introduction of even a single allele significantly ameliorated the severe polycystic kidney disease and consequent runting caused by Bcl2 loss. Significantly, the development of c-MYC-induced acute myeloid leukemia was also accelerated in mice harboring that Mcl1 allele. Our collective findings reveal that, under certain circumstances, the N terminus of Mcl1 regulates its degradation; that some cell types require degradation of Mcl1 to induce apoptosis; and, most importantly, that rapid turnover of Mcl1 can serve as a tumor-suppressive mechanism.

  5. A progress report on the eradication program of the sweet potato weevil, Cylas formicarius (Fabricius) (Coleoptera: Brentidae), with both male annihilation using sex pheromone and sterile insect releases in Kume island, Okinawa, Japan

    International Nuclear Information System (INIS)

    Kohama, Tsuguo; Yamagishi, Masaaki; Kuba, Hiroyuki; Kinjo, Kunio

    2003-01-01

    In order to eradicate Cylas formicarius (Fabricius), an experimental project was started in Kume Island (5600ha) in 1994. The suppression of wild weevils by male annihilation technique (MAT) was conducted from November 1994 to January 1999. Wood fiberboard squares containing synthetic sex pheromone and MEP was used for the MAT. The infestation and trapping data show that the density of the weevil population on the island decreased to approximately one tenth of that before the control experiment began. In February 1999, we started the mass release of sterile weevils. In 2000 and 2001, the infestation rates of vines were 0.4% and 0.16% in peak season. During this period, we conducted intensive host surveys and identified high density areas (hot spots). As a result, we started additional releases into these hot spots in June 2001. From January through December 2002, no wild weevils were found, except on the southeastern coast (20ha) of the island. We thus concluded that C. formicarius seems close to being eradicated. (author)

  6. Silencing of the pollen-specific gene NTP303 and its family members in tobacco affects in vivo pollen tube growth and results in male sterile plants.

    Science.gov (United States)

    de Groot, Peter; Weterings, Koen; de Been, Mark; Wittink, Floyd; Hulzink, Raymond; Custers, Jan; van Herpen, Marinus; Wullems, George

    2004-07-01

    In seed plants, successful fertilization requires correct regulation of pollen tube growth. At germination and during growth, the pollen tube interacts with tissues from the pistil while the pollen tube extends via tip growth. Despite the fact that much research has been devoted to the mechanisms regulating pollen tube growth, many aspects are currently unknown. Previously, we have isolated a pollen-specific gene from tobacco--NTP303--that probably functions during pollen tube growth. NTP303 is part of a family of five members. Its expression is regulated both at the transcriptional and at the translational level. While NTP303 transcripts accumulate to high levels between early bi-cellular and mature pollen stages, NTP303 protein is hardly detectable until germination and pollen tube growth. In order to elucidate the role and function of NTP303 in the pollen tube, we studied the effect of NTP303 gene silencing on pollen function. Therefore, we have transformed tobacco plants with NTP303 co-suppression and anti-sense gene constructs. In these plants, the kanamycin resistance trait--which was linked to the NTP303-silencing gene--was not transmitted through the male gametophyte. This indicated that lowering the transcript level of NTP303 and/or its family members interferes with pollen function. Because we could not find a readily distinguishable phenotype in pollen from the hemizygous anti-sense and co-suppression plants, we rescued the defective pollen to produce doubled haploid plants that were homozygous for the NTP303 anti-sense gene. We found that in pollen from these plants the transcript levels of all NTP303 family members were reduced. Although pollen and pollen tubes from these plants appeared completely normal in vitro, the pollen tubes showed slower growth rates in vivo and arrested in the style before they reached the ovary, so that fertilization failed. These data demonstrate that NTP303 and its family members are essential for normal pollen tube growth

  7. Sterilization of males Diabrotica speciosa (Coleoptera: Chrysomelidae) with gamma irradiation for control in cultures of economic importance; Esterilização de machos de Diabrotica speciosa (Coleoptera: Chrysomelidae) com irradiação gama visando o controle em culturas de importância econômica

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Marcio Martins

    2017-07-01

    Diabrotica speciosa (Germar, 1824), causes direct and indirect damage on crops by feeding and acting as virus vector for diverse groups of plants. The main control form is the use of agrochemicals so, aiming to manage the population without environment impact, the present work had as objective to determine the dose of gamma radiation that provides male sterility, its foliar consumption and gonads histological changes. Adult males were submitted to gamma radiation ({sup 60}Co) on the third day after emergence at doses of 0, 25, 50, 75 and 100 Gy at 0,808 KGy/ hour rate, totaling 20 replicates/ dose. The sterilizing dose was based on the fertility of sexually mature non-irradiated females mated by irradiated males. The couples were individualized in 'arenas' and fed with leaflets Phaseolus vulgaris L. with black gauze moistened for oviposition. Eggs were treated and arranged in plastic containers lined with filter paper. After hatching, larvae were transferred to a larger container with a cover cap containing fine vermiculite and maize seedlings (Zea mays L.), which were replaced every 10 days, until adult emergence. After the 4{sup th} day of irradiation, a leaf disc with 3.2 cm in diameter was available for 24 hours for each couple. The discs were scanned and analyzed in ImageJ software. To evaluate the gonads, 3 males with 8 days of age were used per dose. They were dissected in PBS, through the Hematoxylin-Eosin technique the laminas were evaluated under an optical microscope. We observed that male sterility occurred from 75 Gy and the average longevity of this group was of 12.5 days. Consumption of the leaf area by couples composed by a sterile male was 42.9% and the testicular histological analysis demonstrated tissue disorganisation and gaps between germ cells at the highest doses of 75 Gy and 100 Gy. (author)

  8. 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

  9. Estimation of populations and sterility induction in Anastrepha ludens (Diptera: Tephritidae) fruit flies

    International Nuclear Information System (INIS)

    Flores, Salvador; Montoya, Pablo; Toledo, Jorge; Liedo, Pablo; Enkerlin, Walther

    2015-01-01

    The relationship between different release densities of sterile flies and fly trap captures, expressed as flies per trap per day, in the monitoring of Anastrepha ludens (Loew) populations was evaluated in mango orchards. The induction of sterility in fertile females was evaluated using different ratios of sterile: fertile males under field cage conditions. A direct relationship between recaptured flies and densities of release sterile flies was found. However, trap efficiency, expressed as percentage of recaptured flies, decreased as the density of released flies increased. Sterility induction was positively correlated to the ratio of sterile: fertile flies. A significant difference in egg fertility among treatments was observed. The trajectory of sterility induction slowed down after a sterile: wild ratio of 30:1, which suggests that this ratio could be appropriate in an sterile insect technique program with A. ludens. Sterility induction was greater when only sterile males were released than when releasing both sterile males and females, but the differences were not significant. Our findings contribute to a better interpretation of fly captures obtained from the field trapping networks, and to an improvement in the efficiency of sterile insect technique against A. ludens fruit flies, through the implementation of more rational sterile fly release densities. (author)

  10. A Poisoned Chalice? Why UK Women Engineering and Technology Students May Receive More "Help" than Their Male Peers

    Science.gov (United States)

    Powell, Abigail; Dainty, Andrew; Bagilhole, Barbara

    2011-01-01

    The UK engineering and technology (E&T) sector is male-dominated, with women facing various cultural and structural barriers in entering and developing their careers within it. Existing research in this area has focused on women's recruitment or retaining women in employment, but little has addressed women's transition to industry through the…

  11. [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.

  12. Gamma radiation sterilization of Bactrocera invadens (Diptera ...

    African Journals Online (AJOL)

    The African invader fly, Bactrocera invadens, an invasive pest in Africa since 2003, causes damage and poses a threat to the mango and horticultural industry. Its control is therefore needed. Sterilization of males using gamma radiation doses (25, 50 and 75 Gy) as a means of population control was investigated. Irradiation ...

  13. Mapping of quantitative trait loci for thermosensitive genic male sterility in indica rice Mapeamento de controladores de caracteres quantitativos de macho-esterilidade gênica termossensível em arroz indica

    Directory of Open Access Journals (Sweden)

    Antonio Alberto Neves de Alcochete

    2005-12-01

    Full Text Available The objective of this work was to select and use microsatellite markers, to map genomic regions associated with the genetic control of thermosensitive genic male sterility (TGMS in rice. An F2 population, derived from the cross between fertile and TGMS indica lines, was used to construct a microsatellite-based genetic map of rice. The TGMS phenotype showed a continuous variation in the segregant population. A low level of segregation distortion was detected in the F2 (14.65%, whose cause was found to be zygotic selection. There was no evidence suggesting a cause-effect relationship between zygotic selection and the control of TGMS in this cross. A linkage map comprising 1,213.3 cM was constructed based on the segregation data of the F2 population. Ninety-five out of 116 microsatellite polymorphic markers were assembled into 11 linkage groups, with an average of 12.77 cM between two adjacent marker loci. The phenotypic and genotypic data allowed for the identification of three new quantitative trait loci (QTL for thermosensitive genic male sterility in indica rice. Two of the QTL were mapped on chromosomes that, so far, have not been associated with the genetic control of the TGMS trait (chromosomes 1 and 12. The third QTL was mapped on chromosome 7, where a TGMS locus (tms2 has recently been mapped. Allelic tests will have to be developed, in order to clarify if the two regions are the same or not.O objetivo deste estudo foi selecionar e utilizar marcadores microssatélites, para mapear as regi��es genômicas associadas ao controle genético de macho-esterilidade termossensível (TGMS em arroz. Uma popu- lação F2, derivada do cruzamento entre linhagens indica fértil e TGMS, foi usada para construir um mapa genético de arroz, baseado em marcadores microssatélites. O fenótipo TGMS analisado apresentou uma variação contínua na população segregante. Um baixo nível de distorção da segregação foi detectado na população segregante

  14. Completion of the mitochondrial genome sequence of onion (Allium cepa L.) containing the CMS-S male-sterile cytoplasm and identification of an independent event of the ccmFNgene split.

    Science.gov (United States)

    Kim, Bongju; Kim, Kyunghee; Yang, Tae-Jin; Kim, Sunggil

    2016-11-01

    Cytoplasmic male-sterility (CMS) conferred by the CMS-S cytoplasm has been most commonly used for onion (Allium cepa L.) F 1 hybrid seed production. We first report the complete mitochondrial genome sequence containing CMS-S cytoplasm in this study. Initially, seven contigs were de novo assembled from 150-bp paired-end raw reads produced from the total genomic DNA using the Illumina NextSeq500 platform. These contigs were connected into a single circular genome consisting of 316,363 bp (GenBank accession: KU318712) by PCR amplification. Although all 24 core protein-coding genes were present, no ribosomal protein-coding genes, except rps12, were identified in the onion mitochondrial genome. Unusual trans-splicing of the cox2 gene was verified, and the cox1 gene was identified as part of the chimeric orf725 gene, which is a candidate gene responsible for inducing CMS. In addition to orf725, two small chimeric genes were identified, but no transcripts were detected for these two open reading frames. Thirteen chloroplast-derived sequences, with sizes of 126-13,986 bp, were identified in the intergenic regions. Almost 10 % of the onion mitochondrial genome was composed of repeat sequences. The vast majority of repeats were short repeats of onion ccmF N gene was different from that of other Brassicaceae species. This split of the ccmF N gene was also present in 30 other Allium species. The complete onion mitochondrial genome sequence reported in this study would be fundamental information for elucidation of onion CMS evolution.

  15. Identification of microRNAs and their target genes explores miRNA-mediated regulatory network of cytoplasmic male sterility occurrence during anther development in radish (Raphanus sativus L.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2016-07-01

    Full Text Available MicroRNAs (miRNAs are a type of endogenous non-coding small RNAs that play critical roles in plant growth and developmental processes. Cytoplasmic male sterility (CMS is typically a maternally inherited trait and widely used in plant heterosis utilization. However, the miRNA-mediated regulatory network of CMS occurrence during anther development remains largely unknown in radish. In this study, a comparative small RNAome sequencing was conducted in floral buds of CMS line ‘WA’ and its maintainer line ‘WB’ by high-throughput sequencing. A total of 162 known miRNAs belonging to 25 conserved and 24 non-conserved miRNA families were isolated and 27 potential novel miRNA families were identified for the first time in floral buds of radish. Of these miRNAs, 28 known and 14 potential novel miRNAs were differentially expressed during anther development. Several target genes for CMS occurrence-related miRNAs encoding important transcription factors and functional proteins, which might be involved in multiple biological processes including auxin signaling pathways, signal transduction, miRNA target silencing, floral organ development and organellar gene expression. Moreover, the expression patterns of several CMS occurrence-related miRNAs and their targets during three stages of anther development were validated by qRT-PCR. In addition, a potential miRNA-mediated regulatory network of CMS occurrence during anther development was firstly proposed in radish. These findings contribute new insights into complex miRNA-mediated genetic regulatory network of CMS occurrence and advance our understanding of the roles of miRNAs during CMS occurrence and microspore formation in radish and other crops.

  16. Sterilization by Laparoscopy

    Science.gov (United States)

    ... If pregnancy does occur, the risk of an ectopic pregnancy is higher than in women who did not ... pregnant. Also, the risk of problems, such as ectopic pregnancy, is increased. What are some alternatives to sterilization? ...

  17. 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)

  18. 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.

  19. Degradation of chitosan-based materials after different sterilization treatments

    Science.gov (United States)

    San Juan, A.; Montembault, A.; Gillet, D.; Say, J. P.; Rouif, S.; Bouet, T.; Royaud, I.; David, L.

    2012-02-01

    Biopolymers have received in recent years an increasing interest for their potential applications in the field of biomedical engineering. Among the natural polymers that have been experimented, chitosan is probably the most promising in view of its exceptional biological properties. Several techniques may be employed to sterilize chitosan-based materials. The aim of our study was to compare the effect of common sterilization treatments on the degradation of chitosan-based materials in various physical states: solutions, hydrogels and solid flakes. Four sterilization methods were compared: gamma irradiation, beta irradiation, exposure to ethylene oxide and saturated water steam sterilization (autoclaving). Exposure to gamma or beta irradiation was shown to induce an important degradation of chitosan, regardless of its physical state. The chemical structure of chitosan flakes was preserved after ethylene oxide sterilization, but this technique has a limited use for materials in the dry state. Saturated water steam sterilization of chitosan solutions led to an important depolymerization. Nevertheless, steam sterilization of chitosan flakes bagged or dispersed in water was found to preserve better the molecular weight of the polymer. Hence, the sterilization of chitosan flakes dispersed in water would represent an alternative step for the preparation of sterilized chitosan solutions. Alternatively, autoclaving chitosan physical hydrogels did not significantly modify the macromolecular structure of the polymer. Thus, this method is one of the most convenient procedures for the sterilization of physical chitosan hydrogels after their preparation.

  20. Degradation of chitosan-based materials after different sterilization treatments

    International Nuclear Information System (INIS)

    San Juan, A; Montembault, A; Royaud, I; David, L; Gillet, D; Say, J P; Rouif, S; Bouet, T

    2012-01-01

    Biopolymers have received in recent years an increasing interest for their potential applications in the field of biomedical engineering. Among the natural polymers that have been experimented, chitosan is probably the most promising in view of its exceptional biological properties. Several techniques may be employed to sterilize chitosan-based materials. The aim of our study was to compare the effect of common sterilization treatments on the degradation of chitosan-based materials in various physical states: solutions, hydrogels and solid flakes. Four sterilization methods were compared: gamma irradiation, beta irradiation, exposure to ethylene oxide and saturated water steam sterilization (autoclaving). Exposure to gamma or beta irradiation was shown to induce an important degradation of chitosan, regardless of its physical state. The chemical structure of chitosan flakes was preserved after ethylene oxide sterilization, but this technique has a limited use for materials in the dry state. Saturated water steam sterilization of chitosan solutions led to an important depolymerization. Nevertheless, steam sterilization of chitosan flakes bagged or dispersed in water was found to preserve better the molecular weight of the polymer. Hence, the sterilization of chitosan flakes dispersed in water would represent an alternative step for the preparation of sterilized chitosan solutions. Alternatively, autoclaving chitosan physical hydrogels did not significantly modify the macromolecular structure of the polymer. Thus, this method is one of the most convenient procedures for the sterilization of physical chitosan hydrogels after their preparation.

  1. Auditing radiation sterilization facilities

    Science.gov (United States)

    Beck, Jeffrey A.

    The diversity of radiation sterilization systems available today places renewed emphasis on the need for thorough Quality Assurance audits of these facilities. Evaluating compliance with Good Manufacturing Practices is an obvious requirement, but an effective audit must also evaluate installation and performance qualification programs (validation_, and process control and monitoring procedures in detail. The present paper describes general standards that radiation sterilization operations should meet in each of these key areas, and provides basic guidance for conducting QA audits of these facilities.

  2. Introduction to sterile neutrinos

    Science.gov (United States)

    Volkas, R. R.

    2002-07-01

    Model-building issues raised by the prospect of light sterile neutrinos are discussed in a pedagogical way. I first review the naive proposal that sterile neutrinos be identified with “right handed neutrinos”. A critical discussion of the simple expedient of adding three gauge singlet fermions to the usual minimal standard model matter content is followed by an examination of right handed neutrinos in extended theories. I introduce the terminology of “fully sterile” and “weakly sterile” to classify varieties usually conflated under the sterile neutrino banner. After introducing the concepts of “technical naturalness” and plain “naturalness”, the unbearable lightness of being a sterile neutrino is confronted. This problem is used to motivate mirror neutrinos, whose connection with pairwise maximal mixing is emphasised. Some brief remarks about phenomenology are made throughout. The impossibility of identifying the sole sterile neutrino of the currently favoured 2 + 2 and 3 + 1 phenomenological constructs as a lone gauge singlet fermion added to the minimal standard model is explained. Finally, I remark on the beauty and subtlety of light sterile neutrino cosmology.

  3. 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

  4. Hysteroscopic Tubal Sterilization

    Science.gov (United States)

    McMartin, K

    2013-01-01

    Background Hysteroscopic tubal sterilization is a minimally invasive alternative to laparoscopic tubal ligation for women who want permanent contraception. The procedures involves non-surgical placement of permanent microinserts into both fallopian tubes. Patients must use alternative contraception for at least 3 months postprocedure until tubal occlusion is confirmed. Compared to tubal ligation, potential advantages of the hysteroscopic procedure are that it can be performed in 10 minutes in an office setting without the use of general or even local anesthesia. Objective The objective of this analysis was to determine the effectiveness and safety of hysteroscopic tubal sterilization compared with tubal ligation for permanent female sterilization. Data Sources A standard systematic literature search was conducted for studies published from January 1, 2008, until December 11, 2012. Review Methods Observational studies, randomized controlled trials (RCTs), systematic reviews and meta-analyses with 1 month or more of follow-up were examined. Outcomes included failure/pregnancy rates, adverse events, and patient satisfaction. Results No RCTs were identified. Two systematic reviews covered 22 observational studies of hysteroscopic sterilization. Only 1 (N = 93) of these 22 studies compared hysteroscopic sterilization to laparoscopic tubal ligation. Two other noncomparative case series not included in the systematic reviews were also identified. In the absence of comparative studies, data on tubal ligation were derived for this analysis from the CREST study, a large, multicentre, prospective, noncomparative observational study in the United States (GRADE low). Overall, hysteroscopic sterilization is associated with lower pregnancy rates and lower complication rates compared to tubal ligation. No deaths have been reported for hysteroscopic sterilization. Limitations A lack of long-term follow-up for hysteroscopic sterilization and a paucity of studies that directly

  5. Study on the radiation sterile mechanism of China mulberry wild silkworm (Bombyx mandorina Moore)

    International Nuclear Information System (INIS)

    Yang Rongxin; Xia Darong; Gu Weiping; Meng Zhiqi; Weng Hongbiao

    2000-01-01

    The sterile mechanism of China mulberry wild silkworm (Bombyx mandorina Moore) was studied on the chromosome structure variation by means of 60 Co γ-rays irradiation of the pupae. The dose of sub-sterilization for the wild silkworm was 250 Gy, under which the females of present generation were whole sterilized and the males were sub-sterilized. The chromosome structure variation such as deficiency and inversion of larva reproductive cells could be obviously observed. Most of cells with the abnormal chromosomes were sterilized, which was the main reason or radiation sterilization of Bombyx mandorina Moore

  6. Indução à macho-esterilidade e formação de sementes em genótipos de trigo Induction to male-sterility and cross-pollination in wheat

    Directory of Open Access Journals (Sweden)

    Diego Girardi Pegoraro

    1999-06-01

    variability is obtained through genetic recombination in plants originated from crosses involving contrating genotypes. However, artificial cresses in wheat is a difficult task because of its selfpolinization. The induction of male-sterility may be na altemative for the production of hybrid seeds. The present work had the following objectives: evaluate the efficiency of the gametocide 2-chloroethilphosphonic (Ethrel in the induction of maleterility in wheat, estimate the frequency of crosspoilination in wheat genotypes cultivated in the field, and verify the effect of Ethrel in the production o f wheat hybrid seeds in the field. The product was appiied in five wheat varieties in three different doses in the pre-booting development stage, and the variety BR 43 was used as tester to verify the frequency of crossing. The evaluated traits were: percentage of viable pollen, number of grains produced in protected ears, percentage of artificial and natural cross-poilination. The results indicated that the product Ethrel was efficient in the induction of male-sterility in ali tested genotypes; however, the ovules were aiso affected, evidenced by the reduction in the number of seeds produced in piots treated with the gametocide. The doses of 10l/ha and 20l/ha caused accentuated pollen sterility; on the other hand, na increment in the production of hybrid seeds was not observed. As a consequence, it is necessary to adjust the technique of appiication of Ethrel for the production of hybrid seeds in wheat.

  7. Sterility and meeting competitiveness of medfly, Ceratitis Capitata (Wiedemann)

    International Nuclear Information System (INIS)

    Taein-Tun; Molly-Maung-Maung

    2001-01-01

    The basic methodology in the determination of sterilising dosage in male med flies and mating competitiveness with the normal males was carried out in the laboratory. Application of the Sterile Insect Technique (S.I.T.) by three irradiation dosages on Seib-6096 pupae results in sterility when dosage increased. A lower mating competitiveness was observed with the increase in sterility value. This value was determined from the corrected egg hatch percent. The resulting data showed that irradiation dosage of γ 10.0 Krad gave a good advantage to suppress the population in the next generation. The method suggested a good application in the control and eradication of fruit flies. (author)

  8. 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

  9. Optimizing irradiation dose for sterility induction and quality of Bactrocera tryoni.

    Science.gov (United States)

    Collins, S R; Weldon, C W; Banos, C; Taylor, P W

    2009-10-01

    The current study is an important step toward calibrating, validating, and improving irradiation methods used for Bactrocera tryoni (Froggatt) sterile insect technique (SIT). We used routine International Atomic Energy Agency/U.S. Department of Agriculture/Food and Agriculture Organization quality control tests assessing percentage of emergence, flight ability, sex ratio, mortality under stress, reproductive sterility, and sexual competitiveness, as well as a nonstandard test of longevity under nutritional stress to assess the impact of a range of target irradiation doses (60, 65, 70, 75, and 80 Gy) on the product quality of mass reared B. tryoni used in SIT. Sterility induction remained adequate (>99.5%) for sterile male-fertile female crosses, and 100% sterility was achieved in fertile male-sterile female crosses and sterile male-sterile female crosses for each irradiation doses tested. There was significant increase in mortality under stress as irradiation dose increased, and reduced participation in mating by males irradiated at higher doses. The current target-sterilizing dose for SIT of 70-75 Gy is associated with significant reduction in fly product "quality". Our data suggest that adequate sterility and improved fly quality could be achieved through a small reduction in target sterilizing dose.

  10. Heat sterilization of wood

    Science.gov (United States)

    Xiping Wang

    2010-01-01

    Two important questions should be considered in heat sterilizing solid wood materials: First, what temperature–time regime is required to kill a particular pest? Second, how much time is required to heat the center of any wood configuration to the kill temperature? The entomology research on the first question has facilitated the development of international standards...

  11. 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 oscillation between the two detectors using the v μ→ Vτ transition. A complementary measurement can be made to search for the existence of sterile neutrinos; an oft theorized, but experimentally unvalidated particle. The following thesis will show the results of a sterile neutrino search using MINOS RunI and RunII data totaling ~2.5 x 1020 protons on target. Due to the theoretical nature of sterile neutrinos, complete formalism that covers transition probabilities for the three known active states with the addition of a sterile state is also presented.

  12. Sterilization of Native Americans

    Science.gov (United States)

    Dillingham, Brint

    1977-01-01

    The U.S. State Department's Agency for International Development (AID) is spending more than $143 million this year for population control measures in over 70 nations around the world and it is estimated that as much as $10 million was spent in one year for surgical sterilization procedures. (JC)

  13. About the Sterilization of Chitosan Hydrogel Nanoparticles.

    Directory of Open Access Journals (Sweden)

    Raquel Galante

    Full Text Available In the last years, nanostructured biomaterials have raised a great interest as platforms for delivery of drugs, genes, imaging agents and for tissue engineering applications. In particular, hydrogel nanoparticles (HNP associate the distinctive features of hydrogels (high water uptake capacity, biocompatibility with the advantages of being possible to tailor its physicochemical properties at nano-scale to increase solubility, immunocompatibility and cellular uptake. In order to be safe, HNP for biomedical applications, such as injectable or ophthalmic formulations, must be sterile. Literature is very scarce with respect to sterilization effects on nanostructured systems, and even more in what concerns HNP. This work aims to evaluate the effect and effectiveness of different sterilization methods on chitosan (CS hydrogel nanoparticles. In addition to conventional methods (steam autoclave and gamma irradiation, a recent ozone-based method of sterilization was also tested. A model chitosan-tripolyphosphate (TPP hydrogel nanoparticles (CS-HNP, with a broad spectrum of possible applications was produced and sterilized in the absence and in the presence of protective sugars (glucose and mannitol. Properties like size, zeta potential, absorbance, morphology, chemical structure and cytotoxicity were evaluated. It was found that the CS-HNP degrade by autoclaving and that sugars have no protective effect. Concerning gamma irradiation, the formation of agglomerates was observed, compromising the suspension stability. However, the nanoparticles resistance increases considerably in the presence of the sugars. Ozone sterilization did not lead to significant physical adverse effects, however, slight toxicity signs were observed, contrarily to gamma irradiation where no detectable changes on cells were found. Ozonation in the presence of sugars avoided cytotoxicity. Nevertheless, some chemical alterations were observed in the nanoparticles.

  14. About the Sterilization of Chitosan Hydrogel Nanoparticles.

    Science.gov (United States)

    Galante, Raquel; Rediguieri, Carolina F; Kikuchi, Irene Satiko; Vasquez, Pablo A S; Colaço, Rogério; Serro, Ana Paula; Pinto, Terezinha J A

    2016-01-01

    In the last years, nanostructured biomaterials have raised a great interest as platforms for delivery of drugs, genes, imaging agents and for tissue engineering applications. In particular, hydrogel nanoparticles (HNP) associate the distinctive features of hydrogels (high water uptake capacity, biocompatibility) with the advantages of being possible to tailor its physicochemical properties at nano-scale to increase solubility, immunocompatibility and cellular uptake. In order to be safe, HNP for biomedical applications, such as injectable or ophthalmic formulations, must be sterile. Literature is very scarce with respect to sterilization effects on nanostructured systems, and even more in what concerns HNP. This work aims to evaluate the effect and effectiveness of different sterilization methods on chitosan (CS) hydrogel nanoparticles. In addition to conventional methods (steam autoclave and gamma irradiation), a recent ozone-based method of sterilization was also tested. A model chitosan-tripolyphosphate (TPP) hydrogel nanoparticles (CS-HNP), with a broad spectrum of possible applications was produced and sterilized in the absence and in the presence of protective sugars (glucose and mannitol). Properties like size, zeta potential, absorbance, morphology, chemical structure and cytotoxicity were evaluated. It was found that the CS-HNP degrade by autoclaving and that sugars have no protective effect. Concerning gamma irradiation, the formation of agglomerates was observed, compromising the suspension stability. However, the nanoparticles resistance increases considerably in the presence of the sugars. Ozone sterilization did not lead to significant physical adverse effects, however, slight toxicity signs were observed, contrarily to gamma irradiation where no detectable changes on cells were found. Ozonation in the presence of sugars avoided cytotoxicity. Nevertheless, some chemical alterations were observed in the nanoparticles.

  15. A Molecular Method to Discriminate between Mass-Reared Sterile and Wild Tsetse Flies during Eradication Programmes That Have a Sterile Insect Technique Component.

    Directory of Open Access Journals (Sweden)

    Soumaïla Pagabeleguem

    2016-02-01

    Full Text Available The Government of Senegal has embarked several years ago on a project that aims to eradicate Glossina palpalis gambiensis from the Niayes area. The removal of the animal trypanosomosis would allow the development more efficient livestock production systems. The project was implemented using an area-wide integrated pest management strategy including a sterile insect technique (SIT component. The released sterile male flies originated from a colony from Burkina Faso.Monitoring the efficacy of the sterile male releases requires the discrimination between wild and sterile male G. p. gambiensis that are sampled in monitoring traps. Before being released, sterile male flies were marked with a fluorescent dye powder. The marking was however not infallible with some sterile flies only slightly marked or some wild flies contaminated with a few dye particles in the monitoring traps. Trapped flies can also be damaged due to predation by ants, making it difficult to discriminate between wild and sterile males using a fluorescence camera and / or a fluorescence microscope. We developed a molecular technique based on the determination of cytochrome oxidase haplotypes of G. p. gambiensis to discriminate between wild and sterile males. DNA was isolated from the head of flies and a portion of the 5' end of the mitochondrial gene cytochrome oxidase I was amplified to be finally sequenced. Our results indicated that all the sterile males from the Burkina Faso colony displayed the same haplotype and systematically differed from wild male flies trapped in Senegal and Burkina Faso. This allowed 100% discrimination between sterile and wild male G. p. gambiensis.This tool might be useful for other tsetse control campaigns with a SIT component in the framework of the Pan-African Tsetse and Trypanosomosis Eradication Campaign (PATTEC and, more generally, for other vector or insect pest control programs.

  16. 21 CFR 880.6850 - Sterilization wrap.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Sterilization wrap. 880.6850 Section 880.6850 Food... § 880.6850 Sterilization wrap. (a) Identification. A sterilization wrap (pack, sterilization wrapper... sterilized by a health care provider. It is intended to allow sterilization of the enclosed medical device...

  17. Studies on the ecology of insects sterilized artificially (gamma radiation), 8

    International Nuclear Information System (INIS)

    Kiyoku, Masao; Tsukuda, Ritsuko

    1974-01-01

    Gamma-ray irradiation of 7 KR from 137 Cs on the oriental fruit fly pupae two days before emerging did not significantly reduce the percentage of emergence and longevity of adult flies. However, highly sterile adults (more than 98.9%) were found in those combinations, S#male# x N#female#, N#male# x S#female# and S#male# x S#female#. The result of observation of sperm activity in spermathecae of females mated with sterilized males showed that the sterility is caused by dominant lethalities. The sexual competitiveness between S#male# and N#male# has been examined in experiments of S#male# x N#male# x N#female#. (1) The data suggest that the sterility percentage concerning with egg hatchability is proportional to the rate of sterilized males replaced for normal males when that is expressed with a multiple of the ratio of normal males to normal females. Seven such straight lines thus obtained made us possible to find the theoretical expectation of sterility percentage. (2) Relationship between the percent egg hatch observed (y), or that estimated theoretically (Y), and logarithm of ratio, S#male#/N#male# (x) was showed to be two straight regression equations, y=18.413-11.952 (x - 1.295) and Y=11.890-15.462 (x - 1.295). Ratio of regression coefficients of the equations was 0.772. (3) Correlations between the sterility percentage and ratio, S#male#/N#male#, showed in three convex curves under three degrees of competitiveness (0.265, 0.576 and 1.001). When both the values of S#male#/N#male# in the mating experiments and the sterility percentages are given, it is possible to obtain degrees of competitiveness using the curves. (auth.)

  18. Some Adverse Effects of Used Engine Oil (Common Waste Pollutant On Reproduction of Male Sprague Dawley Rats

    Directory of Open Access Journals (Sweden)

    Wasiu Olalekan Akintunde

    2015-03-01

    Full Text Available AIM: Used oil is contaminated not only with heavy metals but also with polycyclic aromatic hydrocarbons (PAHs that are insignificant in the unused oil. In our study we determined possible reproductive effects of used engine oil on male rats. MATERIAL AND METHODS: Twenty eight male Wistar rats were used for the study. The rats had average weight of 181.5 ± 10 g, animal feeds and portable water was provided ad-libitum. The rats were assigned to 4 groups (n = 7 including control. The treated groups orally received 0.1 ml/rat, 0.2 ml/rat and 0.4 ml/rat of the used engine oil every other day for 28 days using oral canulla. The spermatozoa were collected from epididymis for sperm analysis and testes were removed and preserved in Bouin’s fluid for routine histological analysis. RESULTS: Our results showed that there was progressive weight increase among the control group of rats that received distilled water. Meanwhile, rats that received 0.4 ml/rat of the used engine oil showed significant (P 0.05 weight reduction. The spermatozoa number was decreased with significance (P 0.05. The percentage of head deformity been 41.43 ± 2.61 and 42.00 ± 3.74 at 0.2 ml/rat and 0.4 ml/rat respectively, also significant increase of middle piece deformity was observed only at 0.1 ml/rat (45.71 ± 2.02 while tail deformity significantly decreased (15.71 ± 2.02, 20.00 ± 4.36 and 20.00 ± 4.47 when compared with the control (30.00 ± 1.29. The testicular seminiferous tubules were slightly degenerated with absence of Lumen. The germinal cell layer consisting of necrosis of spermatogonia and interstitial (Leydig cells with affected Sertoli cells at different maturation stages. CONCLUSION: Hence, it can be said that there is a negative relation between used engine oil and male reproductive parameters. And it can be concluded that used engine oil should be  prevented from leaking, spilling or improperly discarded as through medium it may enter storm water runoff and

  19. Sterile neutrino anarchy

    Science.gov (United States)

    Heeck, Julian; Rodejohann, Werner

    2013-02-01

    Lepton mixing, which requires physics beyond the Standard Model, is surprisingly compatible with a minimal, symmetryless and unbiased approach, called anarchy. This contrasts with highly involved flavor symmetry models. On the other hand, hints for light sterile neutrinos have emerged from a variety of independent experiments and observations. If confirmed, their existence would represent a groundbreaking discovery, calling for a theoretical interpretation. We discuss anarchy in the two-neutrino eV-scale seesaw framework. The distributions of mixing angles and masses according to anarchy are in agreement with global fits for the active and sterile neutrino parameters. Our minimal and economical scenario predicts the absence of neutrinoless double beta decay and one vanishing neutrino mass, and can therefore be tested in future experiments.

  20. Abortion and sterilization.

    Science.gov (United States)

    Steele, S J

    1970-01-01

    This discusses activities current in England under the abortion law of April 1968. In England and Wales in 1969 there were 54,013 recorded abortions and 15 related deaths. Since then both the number of deaths and the number of abortions have been increasing. This abortion increase is partly attributed to the adverse publicity regarding the pill which has caused many women to give up oral contraceptives. Complications have included incomplete removal of the products of conception, sepsis, hemorrhage, and perforation of the uterus. There have been wide variation in interpretations of the law by different hospitals and staffs. Sterilization operations are being done in increasing number for both men and women. Carefully worded consent forms are now in use to insure patient understanding and consent. Psychological changes may follow sterilization, but are relatively uncommon. Physicians should do all possible to help women avoid unwanted pregnancies and thereby reduce the demand for termination.

  1. The Boys Club: Engineering a More Positive Environment for Women in Male-Dominated Majors

    Directory of Open Access Journals (Sweden)

    Brooke E. Dresden

    2018-01-01

    Full Text Available Sexual harassment has been widely studied in the workforce, but the factors that contribute to hostile educational environments for women have received less attention. The present study focuses on male dominance, gender harassment, gender threats, masculinity, and their influences on creating a hostile environment for women in academia. One hundred and forty-two male participants from a private university in the Southwestern United States self-reported their masculinity, completed a group task with a female confederate leader serving as a gender threat in half the conditions, and had their subsequent affect, perceptions of leadership effectiveness, and behavioral aggression measured. Men from male-dominated majors and men who had received a gender threat did not differ from men from gender-equivalent majors and men who had not received a gender threat on affect, perceptions of leadership effectiveness, or behavioral aggression (ps > 0.201, ηp2s ≤ 0.007. However, post-hoc analyses revealed that as masculinity increased among men from male-dominated majors under gender threat, they became significantly more behaviorally aggressive (b = 5.92, p = 0.003 and perceived their female leader as less effective (b = −0.83, p = 0.076. Implications and suggestions for future research are discussed.

  2. Sterilization studies on the adult indian meal moth, plodia interpunctella (HUBNER)

    International Nuclear Information System (INIS)

    Boshra, S.A.; Hasaballa, Z.A.

    1993-01-01

    The effects of gamma radiation doses ranging between 10 and 65 krad on adult plodia interpunctella (Hubner) were studied. Irradiation of adult affected clearly the egg production and fertility of both sexes at different mating combinations. Females were more sensitive to the sterilizing effects of gamma radiation than males. Complete sterility of females and males was achieved at 50 and 65 krad, respectively. Replacing normal males by sterile ones in the normal population decreased the egg hatch ability when compared with the control population. Newly emerged unmated females laid completely infertile eggs when confined with irradiated (65 krad) males, whether mating occurred on the day of treatment or 2 days after treatment. Sterilized males were able to compete with normal ones in a population at the highest flooding ratios. Adding sterile females to this competing population gave excellent results.5 tab

  3. Molecular tools for sterile sperm detection to monitor Ceratitis capitata populations under SIT programmes.

    Science.gov (United States)

    Juan-Blasco, María; Sabater-Muñoz, Beatriz; Argilés, Rafael; Jacas, Josep A; Castañera, Pedro; Urbaneja, Alberto

    2013-07-01

    The success of an area-wide sterile insect technique (SIT) programme against Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) relies on the mating success of sterile males in the field. Limited information is available about the effectiveness of sterile males in achieving mates with wild females and how these matings contribute to reducing wild populations. To this end, firstly a mating competition test was performed in the laboratory with different release ratios (1:1:0, 1:1:1, 1:1:5, 1:1:10 and 1:1:20 for wild females:wild males:sterile VIENNA-8 males respectively) and different host fruit. Secondly, the same release ratios were evaluated under semi-natural conditions on caged trees and on sentinel host. By means of molecular markers, VIENNA-8 male sperm was positively detected in those females exposed to the male ratios 1:5, 1:10 and 1:20 in the laboratory. In the field test, sterile VIENNA-8 male matings and the C. capitata progeny on apples were positively correlated with the ratio of sterile males released and with the percentage of sterile matings respectively. These results confirm the validity of using the molecular detection of VIENNA-8 male sperm to predict the C. capitata population under semi-natural conditions. Implications of these results in measuring the efficacy of an SIT programme are discussed. © 2012 Society of Chemical Industry.

  4. Dominant Lethal Pathologies in Male Mice Engineered to Contain an X-Linked DUX4 Transgene

    Directory of Open Access Journals (Sweden)

    Abhijit Dandapat

    2014-09-01

    Full Text Available Facioscapulohumeral muscular dystrophy (FSHD is an enigmatic disease associated with epigenetic alterations in the subtelomeric heterochromatin of the D4Z4 macrosatellite repeat. Each repeat unit encodes DUX4, a gene that is normally silent in most tissues. Besides muscular loss, most patients suffer retinal vascular telangiectasias. To generate an animal model, we introduced a doxycycline-inducible transgene encoding DUX4 and 3′ genomic DNA into a euchromatic region of the mouse X chromosome. Without induction, DUX4 RNA was expressed at low levels in many tissues and animals displayed a variety of unexpected dominant leaky phenotypes, including male-specific lethality. Remarkably, rare live-born males expressed DUX4 RNA in the retina and presented a retinal vascular telangiectasia. By using doxycycline to induce DUX4 expression in satellite cells, we observed impaired myogenesis in vitro and in vivo. This mouse model, which shows pathologies due to FSHD-related D4Z4 sequences, is likely to be useful for testing anti-DUX4 therapies in FSHD.

  5. Electron beam sterilization for dishes

    International Nuclear Information System (INIS)

    Deren, Wang; Meizhen, Fang

    1995-01-01

    Modern biological science often needs various fine strike devices which are often made from non-toxic transparent plastic. The application of high temperature steam to the sterilization as a traditional methods often causes deformation and colour change. When chemicals are applied to the sterilization residure of chemical grain often causes toxicity. Only application of radiation to the sterilization can overcome this faults and carry out with sterility assurance at room temperature. In this research 1.3 MeV electron beam coming from Model JJ-2 accelerator was applied for sterilization to 96-well tissue culture plates. After clean packaging the plates were irradiated with 31.7 XGy and operational voltage 1.3 MeV and 100 μA on the PY device. Repeated tests demonstrate that the products are sterile. The output is 2 x 10 5 pieces for each year. (author)

  6. 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

  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. 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)

  9. Use of sterile insect technique in Brazil by the sterilization of Ceratitis capitata (Wied., 1824)

    International Nuclear Information System (INIS)

    Okeese, G.O.; Kitomer, T.J.; Gayaradus, L.B.; Etrigan, M.; Jansen, C.W.J.H.; Houlahar, H.L.

    2006-01-01

    The Sterile Insect Technique is a method of pest control allowed in Integrated Pest Management programs in fruit growing, where sterile insects released compete in mate process against fertile wild ones, generating a gradative population reduction. The most used sterilization method is using ionizing radiation from 60 Co or 137 Cs. For efficient application of SIT, an important item is the sterilizing dose. This must be as lower as possible in order to preserve insect behavior. In this work, it was studied the reproductive potential of fruit fly Ceratitis capitata, tsl VIENNA 8 strain, irradiated with different doses of gamma radiation. This strain has been used in population suppression programs at fruit-growing areas from Northeast of Brazil, through a partnership between CENA and Bio factory MOSCAMED Brazil, intending only sterile male releases. Radiation source used was a 60 Co irradiator, with 17.2 x 1012 Bq. Individualized couples were distributed in a randomized delineament with 10 replicates for each treatment and eggs were collected for fifteen days. With 9 and 10 days old, pupae were irradiated with doses ranging from 30 to 120 Gy. All averages of emerged adult's percentages were higher than 90%. In regards to fecundity, different doses did not affect the number of eggs laid, being the overall mean around 30 eggs/couple/day. Fertility data showed that as radiation dose increases, sterility increases. It was concluded that the dose of 90 Gy can be used in Brazil, since to SIT programs a dose is chosen witch prevents an egg hatch higher than 1%. (author)

  10. Skilled immigrant labour: country of origin and the occupational locations of male engineers

    Directory of Open Access Journals (Sweden)

    Thomas, Derrick

    2002-01-01

    Full Text Available EnglishDo high skill immigrant workers find employment corresponding to theirtraining? Using unpublished data from the 1996 census, we examine the occupational locations of menage 30-54 who have a university degree with a major in engineering. We focus on three groups: Canadianborn, foreign born who immigrated before age 19 and the foreign-born arriving after age 27... We findbirth place differences in the percentages who are working in managerial, engineering, technical andall other occupations, with differences being most pronounced for those immigrating after age 27.Multinomial logit analysis confirms that these differences cannot be attributed to differences inmeasured human capital stock. Accreditation requirements are one likely explanation, particularly forthose who have received training outside Canada.FrenchLes immigrants hautement qualifiés trouvent-ils de l'emploi correspondant r leur formation? R l'aide de données non publiées du Recensement de 1996, nous examinons la situation professionnelle des hommes de 30?54 ans qui ont un grade universitaire avec majeure en génie. Nous nous intéressons r trois groupes : les personnes nées au Canada, les personnes nées à l'étranger qui ont immigré avant 19 ans et les personnes nées à l'étranger arrivées après 27 ans, partant du principe que les deux premiers groupes sont très susceptibles d'avoir fait leurs études au Canada, au contraire du dernier groupe. Nous observons des différences de lieu de naissance au niveau des pourcentages de ceux qui occupent des postes de direction, en génie, en technique et dans l'qui ont immigré après l'âge de 27 ans. L'analyse multinomiale des logits confirme que ces différences ne peuvent être attribuées à des différences du stock de capital humain mesuré. Les exigences d'accréditation sont une explication probable, particulièrement pour ceux qui ont acquis leur formation à l'extérieur du Canada.

  11. Perceptions of male versus female students enrolled in science, technology, engineering and mathematics courses regarding peer tutoring, a component for student retention

    Science.gov (United States)

    Kingsbury, Cheryl D.

    Academic departments in the areas of science, technology, engineering, and mathematics, strive to develop in students the ability to problem solve, analyze, and to critically think about solutions to problems. Academic departments are committed to success, yet retention rates are lower than would be expected for females in science, technology, engineering, and mathematics fields of study, where female students are underrepresented. The purpose of the study was to explore the perceptions of male and female traditional and nontraditional students who participated in a science, technology, engineering or mathematics STEM course during the spring 2010 semester regarding peer tutoring, and to understand why females are underrepresented and not retained at the same level as males in science, technology, engineering and mathematics STEM courses at the University of North Dakota. The participants in this quantitative study were students enrolled at the University of North Dakota who voluntarily completed a peer tutoring usage survey. A total of 231 students enrolled in Concepts of Biology (Biol 111), Introduction to Chemistry (Chem 115), Advanced Applications of CADD (Tech 202), Material Properties and Selection (ME 313), and College Algebra (Math 103), completed a survey about their spring 2010 semester. Five research questions searched for the differences between male and female perceptions regarding peer tutoring, a component of student retention. The independent variable was gender, the dependent variables were the factors regarding peer tutoring: academic preparedness, academic support and cost, and demographics. Two significant differences were found: (a) females viewed themselves as less prepared for science, technology, engineering, and mathematics courses than did male students, and (b) females were more in favor of the costs of peer tutoring than were male students. These findings support Merton's Self-fulfilling Prophecy Theory. Female students perceived

  12. Sterilization of Lung Matrices by Supercritical Carbon Dioxide.

    Science.gov (United States)

    Balestrini, Jenna L; Liu, Angela; Gard, Ashley L; Huie, Janet; Blatt, Kelly M S; Schwan, Jonas; Zhao, Liping; Broekelmann, Tom J; Mecham, Robert P; Wilcox, Elise C; Niklason, Laura E

    2016-03-01

    Lung engineering is a potential alternative to transplantation for patients with end-stage pulmonary failure. Two challenges critical to the successful development of an engineered lung developed from a decellularized scaffold include (i) the suppression of resident infectious bioburden in the lung matrix, and (ii) the ability to sterilize decellularized tissues while preserving the essential biological and mechanical features intact. To date, the majority of lungs are sterilized using high concentrations of peracetic acid (PAA) resulting in extracellular matrix (ECM) depletion. These mechanically altered tissues have little to no storage potential. In this study, we report a sterilizing technique using supercritical carbon dioxide (ScCO2) that can achieve a sterility assurance level 10(-6) in decellularized lung matrix. The effects of ScCO2 treatment on the histological, mechanical, and biochemical properties of the sterile decellularized lung were evaluated and compared with those of freshly decellularized lung matrix and with PAA-treated acellular lung. Exposure of the decellularized tissue to ScCO2 did not significantly alter tissue architecture, ECM content or organization (glycosaminoglycans, elastin, collagen, and laminin), observations of cell engraftment, or mechanical integrity of the tissue. Furthermore, these attributes of lung matrix did not change after 6 months in sterile buffer following sterilization with ScCO2, indicating that ScCO2 produces a matrix that is stable during storage. The current study's results indicate that ScCO2 can be used to sterilize acellular lung tissue while simultaneously preserving key biological components required for the function of the scaffold for regenerative medicine purposes.

  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. Control of dengue vector by the sterile insect technique considering logistic recruitment

    International Nuclear Information System (INIS)

    Esteva, L.; Yang, H.M.

    2006-01-01

    We propose a mathematical model to assess the effects of irradiated male insects introduction in a previously infested region, taking into account the logistic recruitment of sterile male insects. The release of sterile male insects aims to displace gradually the natural (or wild) insect from the habitat. We discuss the suitability of this release technique when applied to peridomestic adapted Aedes aegypyti mosquitoes which are transmitters of Yellow Fever and Dengue disease. (author)

  15. Control of dengue vector by the sterile insect technique considering logistic recruitment

    Energy Technology Data Exchange (ETDEWEB)

    Esteva, L. [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico). Facultad de Ciencias. Dept. de Matematicas; Lab-Epifisma, Mexico, D.F. (Mexico); Yang, H.M. [Universidade Estadual de Campinas, SP (Brazil). Inst. de Matematica, Estatistica e Ciencia da Computacao. Dept. de Matematica Aplicada; Lab-Epifisma, Campinas, SP (Brazil)

    2006-07-01

    We propose a mathematical model to assess the effects of irradiated male insects introduction in a previously infested region, taking into account the logistic recruitment of sterile male insects. The release of sterile male insects aims to displace gradually the natural (or wild) insect from the habitat. We discuss the suitability of this release technique when applied to peridomestic adapted Aedes aegypyti mosquitoes which are transmitters of Yellow Fever and Dengue disease. (author)

  16. Sterilization of Extracted Human Teeth.

    Science.gov (United States)

    Pantera, Eugene A., Jr.; Schuster, George S.

    1990-01-01

    At present, there is no specific recommendation for sterilization of extracted human teeth used in dental technique courses. The purpose of this study was to determine whether autoclaving would be effective in the sterilization of extracted teeth without compromising the characteristics that make their use in clinical simulations desirable. (MLW)

  17. The Sterile Insect Technique

    International Nuclear Information System (INIS)

    Kiragu, J.

    2006-01-01

    Insect pests have caused an increasing problem in agriculture and human health through crop losses and disease transmission to man and livestock. Intervention to ensure food security and human health has relied on Integrated Pest Management (IPM) strategies to keep the pests population below economic injury levels. IPM integrate a variety of methods, but there has been over-reliance on chemical control following the discovery of insecticidal properties of DDT. It is now realized that, maintaining pest populations at controlled levels is unsustainable and eradication options is now being considered. Although the Sterile Insect Technique(SIT) could be used for insect suppression, it is gaining favour in the elimination (eradication) of the target pest population through Areawide-based IPM (Author)

  18. Ethylene Oxide Gaseous Sterilization

    Science.gov (United States)

    Ernst, Robert R.; Shull, James J.

    1962-01-01

    The duration of the equilibration period between admission of water vapor and subsequent introduction of gaseous ethylene oxide to an evacuated sterilizer chamber was studied with respect to its effect on the inactivation of spores of Bacillus subtilis var. niger under simulated practical conditions. Introduction of a water-adsorbing cotton barrier between the spores and an incoming gas mixture of water vapor and ethylene oxide caused a marked increase in the observed thermochemical death time of the spore populations. This effect was negated by admission of water vapor one or more minutes prior to introduction of ethylene oxide gas. Increases in temperature and relative humidity of the system promoted passage of water vapor through the cotton barriers and diminished their effect. PMID:13890660

  19. 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.

  20. 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.

  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. 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.

  3. Studies on the control of the Mediterranean fruit fly, Ceratitis capitata Wiedemann, using gamma radiation. Part of a coordinated programme on fruit fly eradication or control by the sterile-male technique

    International Nuclear Information System (INIS)

    Wakid, A.M.

    1975-01-01

    Wheat bran and molasses were used in larval medium of the Mediterranean fruit fly, Ceratitis capitata instead of the dried carrot previously used in Egypt. The new larval medium consists of wheat bran, molasses, yeast, sodium benzoate, hydrochloric acid and tap water. This substitution reduced the production costs of pupae in our laboratories. The adults produced from this medium showed almost similar emergence, fecundity, fertility and longevity as those produced from carrot medium. New large larval breeding cabinet was constructed which improved the larval production and can help in mass production purposes. Large oviposition cage was also used instead of the small ones previously used in Egypt. Six field cages made of wire screen, glass and wood were constructed to conduct semi field experiments on the competitiveness of the irradiated males. Competitiveness decreased with increased dose, doses of 5-9 krad led to almost similar reduction in egg hatch. Ratios of 13:13:1:1 and 2:2:1:1 (treated males : treated females : untreated males : untreated females) were tested in the field cages. There was no clear indication of whether male competitiveness of a particular dose was affected by the ratio of irradiated males to untreated males and females. Generally competitiveness of the irradiated males decreased by time. Flight range of the irradiated (9 krad) tagged flies was found to be 700 m within an orchard. Flies released in an orchard did not reach another orchard 700 m far from the release point

  4. Sperm antibody production in female sterility.

    Science.gov (United States)

    Mettler, L; Scheidel, P; Shirwani, D

    1974-01-01

    A review of the immunological implications in reproductive physiology is presented. Although attempts have been made to ascribe the antigenicity of semen to individual components, it has not been possible to isolate the human semen antigen responsible for infertility. In monkeys total ejaculates and seminal plasma have shown higher antigenicity than washed spermatozoa. In bulls some evidence of such antigens have been found in the seminal plasma. They are iron-binding proteins resembling lactoferrin. Most investigators have found no evidence for any participation of the ABO blood group antigens in cases of sterility. On the surface of human spermatozoa histo-incompatibility antigens have been detected. Transplantation antigens may be related to sterility. However, an immulogic tolerance of the maternal organism exists against the genetically foreign fetal tissue. Autoimmune spermagglutinating antibodies have been detected in the sera and in the seminal plasma of males with sterility. An obstruction of the seminal pathways may facilitate the production of such antibodies against retained sperm. Isoimmunity in females against seminal components has been shown in cases of sterility; however, fertile women have also been shown to have such conditions. In a group of infertile women spermagglutination activity was detected in 7.5% of cases. In another series of 46 cases with primary unexplained infertility agglutinating antibodies were found in 17.4%. Other investigators have also reported higher rates than the authors. The sperm immobilization test seems to be more sensitive than the agglutination test. No sera were found positive with both tests. With immunofluorescent techniques humoral sperm antibodies have been found to be the IgM and IgG fractions. Each acts on a different part of the spermatozoa. The only promising therapy against humoral sperm antibodies is avoidance of sperm contact over a long period of time. Reported results have been conflicting. Cortisone

  5. Sociodemographic and Marital Heterogamy Influences on the Decision for Voluntary Sterilization.

    Science.gov (United States)

    Bean, Frank D.; And Others

    1987-01-01

    Examined relationships between religious and age heterogamy and choice of voluntary contraceptive sterilization and decision for male or female procedure. Found that couples of disparate ages and mixed-faith marriages exhibited greater tendency to elect sterilization than did other couples. No relationship emerged between measures of heterogamy…

  6. The perplexing links between contraceptive sterilization and (dis)advantage in ten low-fertility countries1

    Science.gov (United States)

    Eeckhaut, Mieke C. W.; Sweeney, Megan M.

    2015-01-01

    This study investigates the association between sterilization and socioeconomic status in comparative context, using data from the 2006–10 National Survey of Family Growth and the 2004–10 Generations and Gender Surveys. We first confirm that longstanding patterns of association between socioeconomic status and sterilization persist in the contemporary United States. Specifically, female sterilization is associated with economic disadvantage whereas male sterilization is associated with economic advantage. We next show that female sterilization is similarly associated with disadvantage in most study countries, whereas a positive association between socioeconomic advantage and male sterilization is largely unique to the United States. However, while basic demographic background factors such as early childbearing and parity can explain the observed associations in most study countries, a strong gendered association between sterilization and socioeconomic status remains in the U.S. and Belgium even when adjusting for these factors. PMID:26792541

  7. [Sterilization: necessity or genocide?].

    Science.gov (United States)

    Muraro, R M

    1991-01-01

    Recent warnings by the UN Fund for Population Activities about the rapid growth of the world population and the overwhelming role in it played by impoverished women in developing countries are of interest to all women in Latin America. According to the document, Third World Women require drastic improvements in their socioeconomic positions in order to achieve reductions in their family sizes and avoid an increase in the world population from 5 billion at present to 10 billion in 2025, which would be a disaster for the planet. The document states that much of the environmental damage that would occur would be attributable to the combination of poverty and rapid population increase. If the proportion of the world's women using contraceptives increases from the current 45% to 58% by the year 2000, the world population in 2025 will be 8.5 billion. The document recommends that the amount of money invested in family planning be greatly increased by 2000 in order to make possible increased use of family planning. It appears, however, that much of the funding for family planning is under the control of private organizations and is used to serve the interests of foreign countries. The 2 principal private family planning organizations in Brazil, for example, received 18.2 million US dollars between 1978--84, which were used largely to finance a campaign of mass sterilization. Brazil's rate of population growth, which was 2.1% in 1980-85 and 1.8% in 1990, is expected to drop to 1.6% in 1995. With the decline in the rate of growth, the population will be 170 million in 2000 instead of the 220 million projected using data from the 1970s. A much higher proportion of fertile-aged women in Brazil is sterilized than in the US or Europe . Closer examination of the premises behind family planning policies shows them to be questionable. The premise that population density affects the environment is questionable; Japan, West Germany, and Holland have some of the highest population

  8. Effects of radiation on inherited sterility in the European grapevine moth (Lobesia botrana).

    Science.gov (United States)

    Steinitz, Hadass; Sadeh, Adi; Kliot, Adi; Harari, Ally

    2015-01-01

    The sterile insect technique (SIT) is an alternative, environmentally friendly method for controlling insect pests. In the Lepidoptera, a low dose of gamma irradiation causes inherited sterility (SIT-IS), leading to full sterility in females but only partial sterility in males, which successfully compete with wild males for mates. This study examined the effect of a low radiation dose (150 Gy) on the fitness parameters of male and female Lobesia botrana, a polyphagous and major pest of vineyards found in the Middle East, Europe and the Americas. Irradiation of the pupae did not affect their emergence rate, flight ability out of a cylinder, male response to sex pheromone in a field cage or male or female mating success. A major effect of irradiation was observed in the significantly reduced number of irradiated females' offspring reaching pupation, and as a consequence a limited number of F2 offspring. The effect of irradiation on male partial sterility (also called inherited sterility) was reflected in the male-biased sex ratio of F1 offspring of irradiated males, the reduced number of F1 offspring and the very low number of F2 descendants. This study demonstrates the feasibility of controlling L. botrana using SIT-IS. Adding this method to the arsenal of environmentally friendly tools to control this pest may assist in further reducing the use of insecticides on edible crops. © 2014 Society of Chemical Industry.

  9. Exploration of Relationship Between Stress and Spirituality Characteristics of Male and Female Engineering Students: A Comprehensive Study.

    Science.gov (United States)

    Yadav, Radha; Khanna, Ashu; Singh, Dharmendra

    2017-04-01

    This observational paper endeavours to recognize the connection between spirituality and stress. Four types of indicators are utilized for the estimation of anxiety, vis-à-vis, behavioural indicators, emotional indicators, sleep indicators and personal habits. As per pre-documented theory, if spirituality is high within an individual, then his/her stress will be low and vice versa. In college, the stress of education and scoring grades influences the understudy. Information is gathered through a survey in the light of spirituality index and stress index. Findings prove that the indicators of the stress are more visible in female students. Apart from this, there has been not much substantial study in the area of stress and spirituality among college students. Hence, the main purpose of this study was to discuss the various types of stress and effects of spirituality on the engineering students belonging to the age group of 21-26 years, prioritizing the indicators of stress as per the gender of students. The entire study constituted of a sample group of 200 participants, and for the entire process, correlation analysis was used to find the relative relation between spirituality and stress among girls and boys. T test is used for rejection of the null hypothesis. The article focuses on the current issues that students have been facing in the twenty-first century. Result of the study showed that there is a negative relationship between the spirituality and stress of male and female students. Moreover, the article provides unique contribution to the literature and also offers suggestions for generating new research ideas that can be used to ameliorate the problems that plague individuals and organizations in today's world. This is the first article which covers the spirituality and stress of the engineering student and discusses the impact on young adults, as well as highlighting certain ways to overcome stress and enhance spirituality.

  10. Food irradiation and sterilization

    International Nuclear Information System (INIS)

    Josephson, E.S.

    1981-01-01

    Radiation sterilization of food (radappertization) requires exposing food in sealed containers to ionizing radiation at absorbed doses high enough (25 to 70 kGy) to kill all organisms of food spoilage and public health significance. Radappertization is analogous to thermal canning in achieving shelf stability (long term storage without refrigeration). Except for dry products in which autolysis is negligible, the radappertization process also requires that the food be heated to an internal temperature of 70 to 80 0 C (bacon to 53 0 C) to inactivate autolytic enzymes which catalyze spoilage during storage without refrigeration. To minimize the occurrence of irradiation induced off-flavors and odors, undesirable color changes, and textural and nutritional losses from exposure to the high doses required for radappertization, the foods are vacuum sealed and irradiated frozen (-40 0 C to -20 0 C). Radappertized foods have the characteristic of fresh foods prepared for eating. Radappertization can substitute in whole or in part for some chemical food additives such as ethylene oxide and nitrites which are either toxic, carcinogenic, mutagenic, or teratogenic. After 27 years of testing for 'wholesomeness' (safety for consumption) of radappertized foods, no confirmed evidence has been obtained of any adverse effects of radappertization on the 'wholesomeness' characteristics of these foods. (author)

  11. Food irradiation and sterilization

    Science.gov (United States)

    Josephson, Edward S.

    Radiation sterilization of food (radappertization) requires exposing food in sealed containers to ionizing radiation at absorbed doses high enough (25-70 kGy) to kill all organisms of food spoilage and public health significance. Radappertization is analogous to thermal canning is achieving shelf stability (long term storage without refrigeration). Except for dry products in which autolysis is negligible, the radappertization process also requires that the food be heated to an internal temperature of 70-80°C (bacon to 53°C) to inactivate autolytic enzymes which catalyze spoilage during storage without refrigeration. To minimize the occurence of irradiation induced off-flavors and odors, undesirable color changes, and textural and nutritional losses from exposure to the high doses required for radappertization, the foods are vacuum sealed and irradiated frozen (-40°C to -20°C). Radappertozed foods have the characteristic of fresh foods prepared for eating. Radappertization can substitute in whole or in part for some chemical food additives such as ethylene oxide and nitrites which are either toxic, carcinogenic, mutagenic, or teratogenic. After 27 years of testing for "wholesomeness" (safety for consumption) of radappertized foods, no confirmed evidence has been obtained of any adverse effecys of radappertization on the "wholesomeness" characteristics of these foods.

  12. Supercritical Carbon Dioxide–Based Sterilization of Decellularized Heart Valves

    Directory of Open Access Journals (Sweden)

    Ryan S. Hennessy, MD

    2017-02-01

    Full Text Available Summary: Sterilization of grafts is essential. Supercritical carbon dioxide, electrolyzed water, gamma radiation, ethanol-peracetic acid, and hydrogen peroxide techniques were compared for impact on sterility and mechanical integrity of porcine decellularized aortic valves. Ethanol-peracetic acid– and supercritical carbon dioxide–treated valves were found to be sterile using histology, microbe culture, and electron microscopy assays. The cusp tensile properties of supercritical carbon dioxide–treated valves were higher compared with valves treated with other techniques. Superior sterility and integrity was found in the decellularized valves treated with supercritical carbon dioxide sterilization. This sterilization technique may hold promise for other decellularized soft tissues. Key Words: decellularized, decontamination, heart valve, tensile properties, tissue engineering

  13. The perplexing links between contraceptive sterilization and (dis)advantage in ten low-fertility countries.

    Science.gov (United States)

    Eeckhaut, Mieke C W; Sweeney, Megan M

    2016-01-01

    This study investigated the association between contraceptive sterilization and socio-economic status (measured by educational attainment) in ten countries, using data from the 2006-10 National Survey of Family Growth and the 2004-10 Generations and Gender Surveys. The findings confirm that a long-standing association between socio-economic status and sterilization persists in the contemporary United States: female sterilization is associated with economic disadvantage, whereas male sterilization is associated with economic advantage. The latter association is found to be unique to the United States, but female sterilization is associated with disadvantage in most of the other countries studied. While basic demographic background factors such as early childbearing and parity can explain the observed associations in most of the countries, a strong gendered association between sterilization and socio-economic status remains in the United States and Belgium even after adjusting for these factors.

  14. 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....

  15. Sterile pyuria: a forgotten entity

    OpenAIRE

    Goonewardene, Sanchia; Persad, Raj

    2015-01-01

    Sterile pyuria is a common entity. Yet there are no guidelines to address this issue. We have conducted a systematic review over 20 years and reviewed the results. Guidelines for assessment, diagnosis and management are developed based on these results.

  16. Sterile pyuria: a forgotten entity.

    Science.gov (United States)

    Goonewardene, Sanchia; Persad, Raj

    2015-10-01

    Sterile pyuria is a common entity. Yet there are no guidelines to address this issue. We have conducted a systematic review over 20 years and reviewed the results. Guidelines for assessment, diagnosis and management are developed based on these results.

  17. Sterilization of fruit flies (Diptera: Tephritidae) with X-rays for sterile insect technique programs

    International Nuclear Information System (INIS)

    Mastrangelo, Thiago de Araujo

    2009-01-01

    Recent fear of acts of terrorism provoked an increase of delays and denials in the shipment of radioisotopes. This truly represented a menace to sterile insect production projects around the world. In order to validate the use of a new kind of low-energy Xray irradiator, a series of radiobiological studies on Ceratitis capitata (tsl-VIENNA 8 strain) (Wied., 1824) (Diptera: Tephritidae) and an Argentinean strain of Anastrepha fraterculus (Wied., 1830) (Diptera: Tephritidae) were carried out, also comparing biological effectiveness between X-rays and traditional γ radiation from 60 Co. Pupae 48- 24 h before adult emergence of C. capitata males and both sexes of A. fraterculus were irradiated with doses ranging from 15 to 120 Gy and 10 to 70 Gy respectively. Doses that induce 50, 90 and 99% of sterility were estimated and the hypothesis of Parallelism for the Probit equations was tested. Doses of 82.7 Gy of X-rays and 128.2 Gy of γ rays (thus, a RBE∼1.5) induced 99% sterility on medfly males. The fertility of A. fraterculus fertile females crossed with 41 Gy of X-rays and 62.7 Gy of γ rays decreased in 99% comparing with the control group (RBE∼1.5). 99% sterility of A. fraterculus irradiated females was achieved with 60-80 Gy (RBE∼0.7). The standard quality control parameters of fecundity, adult emergence, fliers and survival were not significantly affected by the two types of radiation (RBE∼1) either for medfly or A. fraterculus (p>0.01), being averages in conformity with the values required by FAO/IAEA/USDA. Only fecundity of irradiated A. fraterculus females was severely reduced with increasing doses and no egg was laid at 70 Gy of both radiations. There were no significant differences between X-rays and γ rays regarding mating indices (RSI for medfly, RII, ISI, MRPI and FRPI for A. fraterculus) (p>0.05), what indicated more random matings for fertile and sterile insects. The results demonstrated that no significant difference in biological

  18. Sterility assurance of medical products

    International Nuclear Information System (INIS)

    Dierksheide, W.C.

    1977-01-01

    The present methods of regulating medical devices under the Food, Drug and Cosmetic Act in the United States of America are outlined. Reference is made to the position of drugs sterilized by irradiation. Surgical sutures and surgical dressings are regulated as drugs. Some details are given of proposed changes in the Act. The subject is further discussed under the headings: sterility assurance, and biocompatibility. (U.K.)

  19. 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.)

  20. 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.

  1. 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.

  2. Radiation sterilization of buckwheat flour

    International Nuclear Information System (INIS)

    Ito, Hitoshi; Ishigaki, Isao; Muramatsu, Nobuyuki; Oohinata, Hiroshi; Ohara, Tadahiko; Oh-ike, Terui; Matsuhashi, Tetsujiro.

    1989-01-01

    For buckwheat noodle in which taste is important and its main material, buckwheat flour, the ordinary sterilization by heating or ozone cannot be applied. The number of the bacteria sticking to buckwheat flour is much more as compared with that of wheat flour, and is 10 5 -10 7 per 1 g. The effective countermeasures are not yet found. Also noxious insects are apt to infect buckwheat flour. It has been known that radiation is effective for the sterilization of flavorings. In this study, the microorganism contamination of buckwheat flour and sterilization dose, the change of taste and properties after irradiation, and the capability of storage were examined, and the results are reported. The bacteria in buckwheat flour were mostly Erwinia which forms yellow colonies, and is plant-parasitic bacteria having sugar fermentation function, and also some Enterobacer, Klebsiella and Aspergillus were found. When gamma ray was irradiated on buckwheat flour, it was sterilized to less than 10 3 per 1 g bacteria at the dose of 5 kGy, and microorganisms were almost sterilized at 10 kGy. With the electron beam of 3 MeV, the effect of sterilization somewhat decreased. The noodle-making property of irradiated buckwheat flour, and the taste and storage capability of the noodle of irradiated flour were tested. (K.I.)

  3. The basic principles of the application of sterile insect technique for area-wide insect pest control

    International Nuclear Information System (INIS)

    Singgih Sutrisno

    2006-01-01

    Sterile Insect Technique (SIT) is a new insect pest control technique, potential, and compatible to other techniques. This technique includes irradiation of insect colony in the laboratory using gamma, n, or x-rays and then release them in the field periodically to obtain the increase of sterility probability level from the first generation to the dependence as the result the decrease of the fertility level in the field. The effect the release of sterile insects ( 9:1 ratio to the male indigenous and reproductive potential every single female of each generation reproduce 5 females ) to the insect reduction population model is conceptually discussed. From one million of the female parental decrease to be 26, 316; 1,907; 10; and 0 insects at the first, second, third, and the forth progeny respectively. Then if sterile insect technique integrated with chemical technique (insecticide) 90% kill, it will be much more effective compared to the application sterile insect technique only. From the number of one million population of insects will decrease to be 2,632; 189; and 0 insects at the first, second, and the third progeny respectively. In the Lepidoptera insects was found a phenomenon of inherited sterility. According to Knipling (1970) the inherited sterility in the first offspring caused by chromosome translocation in the gamete . In the individual of heterozygote will be die and in the homozygotes is still alive. Interspecific hybrid sterility first time was found by Laster (1972) from a cross between males Heliothis virescens (F) and females Heliothis subflexa Guenee. Male moths of the first offspring from the cross between H. virescens and H. subflexa is sterile and the females still remain fertile. If the female moths of the first offspring back crossed with male H. virescens the phenomenon of sterility always found will same situation as mention earlier the male offspring is sterile and the females is fertile ( the male F2 will be sterile and the females will

  4. Prevention of chronic alcohol and nicotine-induced azospermia, sterility and decreased libido, by a novel tri-substituted benzoflavone moiety from Passiflora incarnata Linneaus in healthy male rats.

    Science.gov (United States)

    Dhawan, Kamaldeep; Sharma, Anupam

    2002-11-15

    Excessive long term consumption of alcohol and nicotine have serious detrimental effects upon the libido, fertility, and sperm count in male species. The present work describes the beneficial effects of a novel tri-substituted benzoflavone moiety (BZF) isolated from Passiflora incarnata Linneaus, the phyto-chemical isolation, spectroscopic elucidation, and multifarious biological activities of which have recently been reported by the authors. The BZF moiety has been reported to increase libido, sperm count, and sexual fertility in 2 years old male rats at 10 mg/kg, po dose, in the one of our previous studies. Presently, the BZF moiety has been evaluated against chronic ethanol- and nicotine-induced decrease in libido, sexual fertility and mating efficiency in healthy male rats. The male rats were given ethanol (3 g/kg, po) A, nicotine (2 mg/kg, sc) N, alcohol-nicotine combinations (AN) alone, and also with 10 mg/kg po dose of BZF (concurrent administrations). These treatments were given for 30 days. At the end of treatments, it was observed that rat groups A, N, and AN had no libido (evaluated by mounting behaviour), declined sperm count, and consequently no mating efficiency or fertility (upon pairing with pro-estrus female rats). However, the rats which were given 10 mg/kg BZF along-with nicotine (NP group), alcohol (AP group), and alcohol-nicotine combination (ANP) exhibited significant libido-oriented mounting behaviour, increased sperm count (significantly comparable to the control group), and increased fertilization potential. The rats having decreased sperm count, libido and fertilization potential due to chronic administration of alcohol, nicotine and alcohol-nicotine combinations, i.e., rats of A, N, and AN groups were again subdivided and were given 10 mg/kg BZF for 7 days. This treatment confirmed that BZF speeds up the restoration of sexuality in rats upon cessation of the administration of substances like alcohol, nicotine and alcohol

  5. The problem of sterility in men and women after wide area sub-diaphragmatic irradiation

    International Nuclear Information System (INIS)

    Dana, M.; Weisgerber, C.; Teillet, F.; Desprez-Curely, J.P.; Goguel, A.; Chotin, G.; Bernard, J.

    1976-01-01

    Sub-diaphragmatic irradiation in an upside down Y pattern for Hodgkin's disease results in sterility in the woman. Protection consists of irradiating the lumbar chain only when possible or by displacement of the ovary before irradiation, and laterally for preference. Although subsequent pregnancy is then possible, the genetic risk remains. In the male, Y irradiation results in prolonged virtually complete azoospermia. Associated chemotherapy also causes definitive sterility in the male. Collection for a sperm bank before treatment is advised [fr

  6. 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

  7. Sterility inheritance in the irradiated European Corn Borer

    International Nuclear Information System (INIS)

    Rosca, I.; Barbulescu, Al.

    1990-01-01

    The inherited sterility in F 1 and F 2 of the European Corn Borer (Ostrinia nubilalis Hb.) irradiated with sub-sterilizing doses of 10 and 15 Krad has been studied at Research Institute for Cereals and Industrial Crops, Fundulea, Romania. Irradiations were done with a 60 Co source delivering 1,805 roentgen/h/m in containers of 23 mm diameter and 125 mm height, placed apart from the 60 Co source. Following irradiation of male parent generation, no significant differences were recorded in F 1 and F 2 referring to the number of deposited egg-batches and adult longevity. Nevertheless, there was a significant decrease of the percentage of viable eggs and an increase of the number of sterile couples. (author)

  8. Radiation: A means of sterilization

    International Nuclear Information System (INIS)

    Mukherjee, R.N.

    1975-01-01

    The sterilization of medical products by ionizing radiation is a well-established industrial process in a number of technologically advanced countries. It is indeed encouraging to note the rate of growth experienced during the past fifteen years. Starting with the first commercial plant in the early sixties in the USA there are to date more than sixty large facilities of this kind located in USA, Canada, Australia and the countries of Europe including USSR. The geographical distribution of these sterilization plants is rather unbalanced. In this respect Europe is far ahead of the other continents of the world, with about 65% of all sterilization plants, followed by North and South America with 17%, Asia with 8%, Australia and New Zealand with 9% and Africa with only 1%. During the last 10 years the IAEA has actively contributed to the development of radiation sterilization practices and technology in the Member States, with particular emphasis on the developing countries. Such promotional efforts have been made by (a) supporting co-ordinated research to accumulate relevant technical information, (b) organizing scientific meetings and training courses, (c) providing technical expertise in the form of fellowships and expert services, (d) providing technical assistance to conduct market surveys and economic feasibility assessment, (e) scientific publications, including technical manuals and proceedings reports, and (f) assistance in the formulation of an international 'Code of Practice' for standardization of the manufacturing practices for radiation sterilized medical products to meet the specified requirements of the various national Pharmacopoeias and of the international consumer market

  9. Neutrinos in a Sterile Throat

    CERN Document Server

    Gripaios, Ben Matthew

    2007-01-01

    We consider field-theoretic models of a warped extra dimension with multiple throats, in which fermions that are singlets of the Standard Model gauge group propagate in a separate throat from the Standard Model fields, which we call the sterile throat. The singlets mix with Standard Model fields via interactions localized on the UV brane that connects the two throats. This leads to three, light, mostly-active, Majorana neutrinos via a higher-dimensional see-saw mechanism, together with Kaluza-Klein towers of mostly-sterile neutrinos, whose scale is set by the warp factor in the sterile throat and can be very low if the throat is deep. We suggest that a model of this kind may explain all the neutrino data, reconciling the LSND result with astrophysical constraints.

  10. Determination of the sterile release rate for stopping growing age-structured populations

    International Nuclear Information System (INIS)

    Barclay, Hugh John

    2016-01-01

    A freely-growing age-structured population was modelled for growth and control by sterile male releases. Equilibrium populations yield critical sterile male release rates that would hold the population at equilibrium. It is shown here that these rates may be different from the release rates required to stop a growing population and bring it to an equilibrium. A computer simulation was constructed of this population and a parameter sensitivity analysis graphed the effects on the required sterile male release rate of fertility, mating delay in adult females, net juvenile survivorship, three adult survivorship curves, the time spent in the juvenile stages, and total life span. The adult survivorship curves had the greatest effect on the required sterile release rate for population elimination. The required release rate was also determined for Ceratitis capitata (Wiedemann) using survivorship and fertility data from a laboratory strain. The concepts of over-flooding ratio and release ratio were discussed and quantified for the cases above. (author)

  11. A soybean MADS-box protein modulates floral organ numbers, petal identity and sterility.

    Science.gov (United States)

    Huang, Fang; Xu, Guangli; Chi, Yingjun; Liu, Haicui; Xue, Qian; Zhao, Tuanjie; Gai, Junyi; Yu, Deyue

    2014-04-02

    The MADS-box transcription factors play fundamental roles in reproductive developmental control. Although the roles of many plant MADS-box proteins have been extensively studied, there are almost no functional studies of them in soybean, an important protein and oil crop in the world. In addition, the MADS-box protein orthologs may have species-specific functions. Controlling male fertility is an important goal in plant hybrid breeding but is difficult in some crops like soybean. The morphological structure of soybean flowers prevents the cross-pollination. Understanding the molecular mechanisms for floral development will aid in engineering new sterile materials that could be applied in hybrid breeding programs in soybean. Through microarray analysis, a flower-enriched gene in soybean was selected and designated as GmMADS28. GmMADS28 belongs to AGL9/SEP subfamily of MADS-box proteins, localized in nucleus and showed specific expression patterns in floral meristems as well as stamen and petal primordia. Expression of GmMADS28 in the stamens and petals of a soybean mutant NJS-10Hfs whose stamens are converted into petals was higher than in those of wild-type plants. Constitutive expression of GmMADS28 in tobacco promoted early flowering and converted stamens and sepals to petals. Interestingly, transgenic plants increased the numbers of sepal, petal and stamen from five to six and exhibited male sterility due to the shortened and curly filaments and the failure of pollen release from the anthers. The ectopic expression of GmMADS28 was found to be sufficient to activate expression of tobacco homologs of SOC1, LEAFY, AGL8/FUL, and DEF. In addition, we observed the interactions of GmMADS28 with soybean homologs of SOC1, AP1, and AGL8/FUL proteins. In this study, we observed the roles of GmMADS28 in the regulation of floral organ number and petal identity. Compared to other plant AGL9/SEP proteins, GmMADS28 specifically regulates floral organ number, filament length and

  12. Agronomic performance of male-sterile and fertile maize genotypes at two plant populations Performace agronômica de genótipos macho-estéreis e férteis de milho em duas densidades de semeadura

    Directory of Open Access Journals (Sweden)

    Luís Sangoi

    1996-12-01

    Full Text Available This experiment was conducted in 1994 at Ames, Iowa, US to test whether cytoplasmic male-sterility can be used to decrease barrenness and to increase grain yield of maize at two plant populations. Four genotypes were tested: a hybrid (NK 6330 and an inbred, wifh sterile and fertile counterparts. Each genotype owas evaluated at plant populations equivalent to 25,000 and 75,000 pl. ha-1. Hybrids produced higher grain yield than inbreds at both plant populations. Gram yield was higher at 75,000 than at 25,000 pl. ha-1. No difference in gram yield, number of ears per plant, number of grains per ear, tassel length, and tassel number of branches was found between sterile and fertile counterparts of the inbred and hybrid, regardiess of plant population. Fertile genotypes bore heavier tassels at anthesis than their sterile counterparts. Adequate precipitation distribution and high fertility level in the soil probably decreased competition between tassel and ears, mitigating potential yield benefits of suppressing genetically pollen production.Este experimento foi conduzido em Ames, Iowa, US durante o ano agrícola de 1994, tendo como objetivo avaliar se a macho-esterelidade genético-citoplasmática pode ser utilizada para aumentar o rendimento de grãos de milho em diferentes populações de planta. Quatro genótipos foram utilizados: um híbrido (NK 6330 e uma linhagem, ambos em suas versões fértil e macho-estéril. Cada genótipo foi avaliado em duas densidades de semeadura, equivalentes a 25.000 e 75.000 pl.ha-1. Os híbridos produziram maiores rendimentos de grão do que as linhagens nas duas populações utilizadas. O rendimento de grãos por área foi maior em 75.000 do que em 25.000 pl.ha-1. Nenhuma diferença significativa em termos de rendimento de grãos, número de espigas por planta, número de grãos por espiga, comprimento e número de ramos do pendão, foi observada entre genótipos férteis e macho-estéreis, independentemente da

  13. Radiation sterilization of hydrocortisone acetate

    International Nuclear Information System (INIS)

    Charef, A.; Boussaha, A.

    1989-09-01

    The feasibility of using high energy ionizing radiation for the sterilization of hydrocortisone acetate was investigated. Hydrocortisone acetate in the form of powder was exposed to different dose levels of gamma radiation using a Cobalt-60 source. The irradiated samples were examined by various physico-chemical techniques in order to detect possible radiolysis products. It was of interest to know if one could insure sterility and retain biological properties of the drug by suitable choice of radiation dose. The results showed that a 10 KGy radiation dose causes no change in the physico-chemical properties of the drug and is sufficient to obtain contaminant-free product

  14. Widespread over-expression of the X chromosome in sterile F₁hybrid mice.

    Directory of Open Access Journals (Sweden)

    Jeffrey M Good

    2010-09-01

    Full Text Available The X chromosome often plays a central role in hybrid male sterility between species, but it is unclear if this reflects underlying regulatory incompatibilities. Here we combine phenotypic data with genome-wide expression data to directly associate aberrant expression patterns with hybrid male sterility between two species of mice. We used a reciprocal cross in which F₁ males are sterile in one direction and fertile in the other direction, allowing us to associate expression differences with sterility rather than with other hybrid phenotypes. We found evidence of extensive over-expression of the X chromosome during spermatogenesis in sterile but not in fertile F₁ hybrid males. Over-expression was most pronounced in genes that are normally expressed after meiosis, consistent with an X chromosome-wide disruption of expression during the later stages of spermatogenesis. This pattern was not a simple consequence of faster evolutionary divergence on the X chromosome, because X-linked expression was highly conserved between the two species. Thus, transcriptional regulation of the X chromosome during spermatogenesis appears particularly sensitive to evolutionary divergence between species. Overall, these data provide evidence for an underlying regulatory basis to reproductive isolation in house mice and underscore the importance of transcriptional regulation of the X chromosome to the evolution of hybrid male sterility.

  15. "Absolute" sterility and "absolute" freedom from particle contamination.

    Science.gov (United States)

    Knapp, J Z

    1998-01-01

    standardization of the results of a visual inspection for contaminating particles. The control of particle contamination in injectable products is a two-fold problem for the pharmaceutical industry. The two parts of the problem are 1) achieving contamination free product and 2) achieving this contamination free quality at an economic cost acceptable to the user. Today, there is no commonly accepted framework for the definition or analysis of the results of a manual inspection for "visible" particles. Any progress toward global harmonization of the results of a visual particle inspection must commence with the development of a common scientific language with which inspection security and economic effectiveness of an inspection can be discussed and rationally evaluated. The tools with which to define and control the results of this inspection have been developed in biophysics, illumination engineering, optics, pharmaceutical manufacturing and statistics. With them, statistically replicable measures have been developed. The statistically replicable measures are then used to evaluate the results of semi- and fully automated particle inspection systems in terms of human inspection performance. The numerical evaluation of both the freedom from contamination achieved with an inspection for particle contamination and the economic effectiveness of the inspection are compared to Pflug's sterility index. In the case of particle contamination, the final product quality depends on product quality prior to inspection and to the parameters of the inspection process.

  16. The effects of gamma radiation in nitrogen and air atmosphere on the sterility of crocidolomia binotalis zell

    International Nuclear Information System (INIS)

    Sastradihardja, S.I.; Sutrisno, S.

    1979-01-01

    Doses of 0, 5, 10, 15, 20, 25, 30, 35, 40, and 45 Krad were given to six-day old sexed pupae in nitrogen and air atmosphere to study its effects on sterility. A dose of 45 Krad caused 100% sterility on male in both air and nitrogen atmosphere on females 100% sterility was found at a dose of 20 Krad in air atmosphere and 25 Krad in nitrogen atmosphere. (author)

  17. Sterilization of Helicoverpa armigera (hubner) moth (lepidoptera; Noctudae) by using Gamma rays radiation

    International Nuclear Information System (INIS)

    Subiyakto; Wari D Astati; Sunarto Dwi A

    1998-01-01

    This experiment was conducted at the Radiation Facility, National Atomic Energy, Jakarta and Entomology Laboratory of the Research Institute for Tobacco and Crops Malang in 1991. Sterilization of moth by radiating insect on pupae stage. The dosage were 0 (unradiated), 1,3,5,7,9,11,13,and 15 krad. The treatments were arranged in complete randomized design with three replications. Each treatments were made variation of copulation (1) two females radiated with a make unradiated (2) two females unradiated with a male radiated, and (3) two females radiated with a male radiated. The results showed that sub sterile dosage (LD 50 ) for male was 0.94 krad and 7.02 krad for female. The sterile dosage (LD 95 ) for male was 10.85 krad and 14.35 krad for female. Research of the competition for copulation between the male radiated and unradiated is needed. (author)

  18. Radiation treatment for sterilization of packaging materials

    International Nuclear Information System (INIS)

    Haji-Saeid, Mohammad; Sampa, Maria Helena O.; Chmielewski, Andrzej G.

    2007-01-01

    Treatment with gamma and electron radiation is becoming a common process for the sterilization of packages, mostly made of natural or synthetic plastics, used in the aseptic processing of foods and pharmaceuticals. The effect of irradiation on these materials is crucial for packaging engineering to understand the effects of these new treatments. Packaging material may be irradiated either prior to or after filling. The irradiation prior to filling is usually chosen for dairy products, processed food, beverages, pharmaceutical, and medical device industries in the United States, Europe, and Canada. Radiation effects on packaging material properties still need further investigation. This paper summarizes the work done by different groups and discusses recent developments in regulations and testing procedures in the field of packaging technology

  19. [The psychosocial background of sterile patients].

    Science.gov (United States)

    Pusch, H H; Urdl, W; Walcher, W

    1989-01-01

    The psychosocial background of 300 childless couples from the Infertility Clinic of the Department of Gynecology and Obstetrics, University of Graz, was evaluated by means of a questionnaire and statistical analysis of data from their files. Points of special interest were problems such as interactions of the couple, motivations for the desire of children, psychosomatics, andrological investigation within the gynecological department, sexual habits and motivation and compliance concerning investigations and treatment. 72% of the questionnaires were returned. 50% of the sterile couples preferred to attend the infertility clinic together. 26% felt restrictions in their sexual behaviour due to the unrealized desire of children, 48% expected improvements in their partnership if they could have children. Compliance of male partners concerning the regular intake of prescribed medicaments was 83%, 63% accepted to stop smoking in cases of pathospermia.

  20. 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....

  1. Establishment of a sterilization dose

    International Nuclear Information System (INIS)

    Kaluska, I.

    2007-01-01

    Factors that impact on product bioburden (population of diable microorganisms on or in product and/or sterile barrier system) are: Raw materials, components, product design and size, manufacturing process, manufacturing equipment, manufacturing environment and manufacturing location. Presented lecture describes all these factors in details

  2. 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.

  3. Sterilization In Protective Trade Policies

    OpenAIRE

    寺崎, 克志; Katsushi, Terasaki; 経営学部経営学科

    2007-01-01

    Under a government budget constraint export subsidies automatically sterilize distortions caused by import tariffs, i.e., without the cost of the trade policy implementation the policy mix of export subsidies and import tariffs with budget constraint makes the economy effective.

  4. Influence of modifying factors on induction of sterility and mating ability of potato tuberworm, Phthorimaea operculella (Zeller)

    International Nuclear Information System (INIS)

    Rananavare, H.D.; Harwalkar, M.R.; Rahalkar, G.W.

    1991-01-01

    Influence of modifying factors like dose fractionation, temperature, gaseous atmosphere and photoperiod on induction of sterility and mating ability of potato tuberworm was evaluated. Fractionation of 50 Krad (0.50 kGy) and 55 Krad (0.55 kGy) doses administered to adult males had no effect on the level of sterility induced, but there was improvement in the mating ability, when the dose was given in two equal fractions. Low temperature during irradiation had no significant effect on the level of sterility induced except that of marginal improvement in the mating competitiveness. When males were irradiated during scotophase of 14 L :10 D photoperiod, there was marginal decrease in the level of induced sterility. Sterility induced in males irradiated under nitrogen atmosphere was significantly lower than those irradiated in air. (author). 16 refs., 4 tabs

  5. Radiation sterilization: an industrial process

    International Nuclear Information System (INIS)

    Ley, F.J.

    1975-01-01

    A new dimension has been added to the use of radiation in the medical field with the introduction of radiation as a sterilizing agent. Its use in diagnosis through radioactive tracers or X-rays and in therapy administered with the most sophisticated of electrical machines or radioisotope units, is familiar in the hospital world, being well established therein. In contrast, the application of radiation sterilization is in industry where the installation of large radiation sources is already commonplace in many countries. The beginnings in the early 1950's centered on the Van de Graaff machine and linear accelerators and the pioneering efforts of Ethicon Inc. here in the United States must be recognized. However, although sterilization with electron beams is still current practice in a number of plants, the use of gamma rays from cobalt-60 is preferred. The first steps in this direction were taken by the U.K.A.E.A. which, in common with similar organizations elsewhere, was attempting to exploit the tremendous potential for cobalt-60 production arising through the rapid construction of nuclear reactors. The first full-scale commercial gamma plant was commissioned in the U.K. in 1960. It reached a loading of 500,000 curies before its demolition after twelve years of operation. The process gained rapid acceptance within industry and approval by health authorities because it provided a ''cold'' sterilization method combining the property of lethal effect with penetration. Its immediate impact occurred in the introduction of disposable products making it possible, for example, to use heat-labile plastics and new packaging materials and package designs. Certainly, the technique has proved complementary to sterilization methods based on heat and to the use of chemical agents, in particular ethylene oxide gas

  6. Implementação da seleção recorrente no melhoramento de plantas autógamas através da macho-esterilidade Implementation of recurrent selection in plant breding of autogamous crops through male sterility

    Directory of Open Access Journals (Sweden)

    Paulo Cesar Canci

    1997-08-01

    Full Text Available Os sistemas de melhoramento convencionais baseados no método genealógico, utilizados principalmente em cereais de estação fria, determinam a redução da variabilidade e da capacidade de recombinação, devido a utilização de um número de genitores limitado nos cruzamentos. O incremento da probabilidade de recombinação através da seleção recorrente pelo aumento do número de cruzamentos pode ser a saída para este problema. A utilização da macho-esterilidade representa uma alternativa viável para propiciar o cruzamento natural em espécies de autofecundação, favorecendo a utilização da seleção recorrente como uma importante ferramenta para o melhoramento de plantas autógamas.The mechanism of pedigree system used in smallgrain cereals reduce genetic variability and recombination capacity due to the limited number of parent used in crosses. The increase in recombination through recurrent selection by maximizing number of crosses may be a solution for this problem. The use of male sterility may overcome the difficult of performing artificial crosses, supporting recurrent selection as a viable and important tool for autogamous crops breeding.

  7. 45 CFR 96.73 - Sterilization.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Sterilization. 96.73 Section 96.73 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION BLOCK GRANTS Social Services Block Grants § 96.73 Sterilization. If a State authorizes sterilization as a family planning service, it must comply...

  8. Reversal of sterilization by microsurgical technique.

    Science.gov (United States)

    Gaspari, A L; Ortensi, A; Parlangeli, V; Pellizzari, G; Setti, C; Lania, M

    1988-01-01

    Tubal sterilization techniques that spare the fimbriae and cause the least amount of tubal destruction offer the best chance for reversal of sterilization. Patients seeking reversal of sterilization should be carefully selected. Surgical technique and equipment are important factors in reversal procedures; microsurgical techniques are shown to be more effective than macroscopic techniques.

  9. A novel approach identifying hybrid sterility QTL on the autosomes of Drosophila simulans and D. mauritiana.

    Directory of Open Access Journals (Sweden)

    Christopher T D Dickman

    Full Text Available When species interbreed, the hybrid offspring that are produced are often sterile. If only one hybrid sex is sterile, it is almost always the heterogametic (XY or ZW sex. Taking this trend into account, the predominant model used to explain the genetic basis of F1 sterility involves a deleterious interaction between recessive sex-linked loci from one species and dominant autosomal loci from the other species. This model is difficult to evaluate, however, as only a handful of loci influencing interspecies hybrid sterility have been identified, and their autosomal genetic interactors have remained elusive. One hindrance to their identification has been the overwhelming effect of the sex chromosome in mapping studies, which could 'mask' the ability to accurately map autosomal factors. Here, we use a novel approach employing attached-X chromosomes to create reciprocal backcross interspecies hybrid males that have a non-recombinant sex chromosome and recombinant autosomes. The heritable variation in phenotype is thus solely caused by differences in the autosomes, thereby allowing us to accurately identify the number and location of autosomal sterility loci. In one direction of backcross, all males were sterile, indicating that sterility could be entirely induced by the sex chromosome complement in these males. In the other direction, we identified nine quantitative trait loci that account for a surprisingly large amount (56% of the autosome-induced phenotypic variance in sterility, with a large contribution of autosome-autosome epistatic interactions. These loci are capable of acting dominantly, and thus could contribute to F1 hybrid sterility.

  10. 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

  11. Comparison of postoperative surgical site infection after preoperative marking done with non-sterile stationary grade markers versus sterile surgical markers

    International Nuclear Information System (INIS)

    Mir, Z.A.

    2015-01-01

    Objectives: To compare the frequencies of post- operative surgical site infection after preoperative marking done with non-sterile stationary. grade markers versus sterile surgical markers in the same patient. Design: Randomized control trial. Place and Duration of Study: The department of Plastic surgery, Mayo hospital, Lahore from August 2013 to August 2014. Methods: This study was conducted after taking approval from the departmental ethical committee. Forty consecutive patients were included. A sterile surgical marker was used to mark one incision site while an alcohol based stationary grade marker was used to mark another incision site on the same patient. A standard preoperative, intraoperative and postoperative protocol was followed. Cultures were performed on swabs taken from the incision sites and surgical site infection was assessed for 30 days. Results: The study included 40 patients; 17 males and 23 females. The mean age of subjects was 25.32 ± 19.69 years with the minimum age being 2 years and the maximum being 63 years. No growth was seen in cultures taken from all the incision sites after skin preparation in the non sterile stationary grade marker group as well as the sterile surgical grade marker group. Also no surgical site infection appeared during the 30 day postoperative observation period in the non sterile stationary grade marker group as well as the sterile surgical grade marker group. (author)

  12. Microwave Sterilization and Depyrogenation System

    Science.gov (United States)

    Akse, James R.; Dahl, Roger W.; Wheeler, Richard R., Jr.

    2009-01-01

    A fully functional, microgravity-compatible microwave sterilization and depyrogenation system (MSDS) prototype was developed that is capable of producing medical-grade water (MGW) without expendable supplies, using NASA potable water that currently is available aboard the International Space Station (ISS) and will be available for Lunar and planetary missions in the future. The microwave- based, continuous MSDS efficiently couples microwaves to a single-phase, pressurized, flowing water stream that is rapidly heated above 150 C. Under these conditions, water is rapidly sterilized. Endotoxins, significant biological toxins that originate from the cell walls of gram-negative bacteria and which represent another defining MGW requirement, are also deactivated (i.e., depyrogenated) albeit more slowly, with such deactivation representing a more difficult challenge than sterilization. Several innovations culminated in the successful MSDS prototype design. The most significant is the antenna-directed microwave heating of a water stream flowing through a microwave sterilization chamber (MSC). Novel antenna designs were developed to increase microwave transmission efficiency. These improvements resulted in greater than 95-percent absorption of incident microwaves. In addition, incorporation of recuperative heat exchangers (RHxs) in the design reduced the microwave power required to heat a water stream flowing at 15 mL/min to 170 C to only 50 W. Further improvements in energy efficiency involved the employment of a second antenna to redirect reflected microwaves back into the MSC, eliminating the need for a water load and simplifying MSDS design. A quick connect (QC) is another innovation that can be sterilized and depyrogenated at temperature, and then cooled using a unique flow design, allowing collection of MGW at atmospheric pressure and 80 C. The final innovation was the use of in-line mixers incorporated in the flow path to disrupt laminar flow and increase contact time

  13. Sterilization of Exopolysaccharides Produced by Deep-Sea Bacteria: Impact on Their Stability and Degradation

    Directory of Open Access Journals (Sweden)

    Sylvia Colliec-Jouault

    2011-02-01

    Full Text Available Polysaccharides are highly heat-sensitive macromolecules, so high temperature treatments are greatly destructive and cause considerable damage, such as a great decrease in both viscosity and molecular weight of the polymer. The technical feasibility of the production of exopolysaccharides by deep-sea bacteria Vibrio diabolicus and Alteromonas infernus was previously demonstrated using a bioproduct manufacturing process. The objective of this study was to determine which sterilization method, other than heat sterilization, was the most appropriate for these marine exopolysaccharides and was in accordance with bioprocess engineering requirements. Chemical sterilization using low-temperature ethylene oxide and a mixture of ionized gases (plasmas was compared to the sterilization methods using gamma and beta radiations. The changes to both the physical and chemical properties of the sterilized exopolysaccharides were analyzed. The use of ethylene oxide can be recommended for the sterilization of polysaccharides as a weak effect on both rheological and structural properties was observed. This low-temperature gas sterilizing process is very efficient, giving a good Sterility Assurance Level (SAL, and is also well suited to large-scale compound manufacturing in the pharmaceutical industry.

  14. Terminal sterilization of alginate hydrogels: efficacy and impact on mechanical properties.

    Science.gov (United States)

    Stoppel, Whitney L; White, Joseph C; Horava, Sarena D; Henry, Anna C; Roberts, Susan C; Bhatia, Surita R

    2014-05-01

    Terminal, or postprocessing, sterilization of composite biomaterials is crucial for their use in wound healing and tissue-engineered devices. Recent research has focused on optimizing traditional biomaterial formulations to create better products for commercial and academic use which incorporate hydrophobic compounds or secondary gel networks. To use a hydrogel in a clinical setting, terminal sterilization is necessary to ensure patient safety. Lyophilization, gamma-irradiation, and ethylene oxide treatment all have negative consequences when applied to alginate scaffolds for clinical use. Here, we aim to find alternative terminal sterilization methods for alginate and alginate-based composite hydrogels which maintain the structure of composite alginate networks for use in biomedical applications. A thorough investigation of the effect of common sterilization methods on swollen alginate-based hydrogels has not been reported and therefore, this work examines autoclaving, ethanol washing, and ultraviolet light as sterilization techniques for alginate and alginate/Pluronic® F68 composite hydrogels. Preservation of structural integrity is evaluated using shear rheology and analysis of water retention, and efficacy of sterilization is determined via bacterial persistence within the hydrogel. Results indicate that ethanol sterilization is the best method of those investigated because ethanol washing results in minimal effects on mechanical properties and water retention and eliminates bacterial persistence. Furthermore, this study suggests that ethanol treatment is an efficacious method for terminally sterilizing interpenetrating networks or other composite hydrogel systems. Copyright © 2013 Wiley Periodicals, Inc.

  15. Sterilization of Exopolysaccharides Produced by Deep-Sea Bacteria: Impact on Their Stability and Degradation

    Science.gov (United States)

    Rederstorff, Emilie; Fatimi, Ahmed; Sinquin, Corinne; Ratiskol, Jacqueline; Merceron, Christophe; Vinatier, Claire; Weiss, Pierre; Colliec-Jouault, Sylvia

    2011-01-01

    Polysaccharides are highly heat-sensitive macromolecules, so high temperature treatments are greatly destructive and cause considerable damage, such as a great decrease in both viscosity and molecular weight of the polymer. The technical feasibility of the production of exopolysaccharides by deep-sea bacteria Vibrio diabolicus and Alteromonas infernus was previously demonstrated using a bioproduct manufacturing process. The objective of this study was to determine which sterilization method, other than heat sterilization, was the most appropriate for these marine exopolysaccharides and was in accordance with bioprocess engineering requirements. Chemical sterilization using low-temperature ethylene oxide and a mixture of ionized gases (plasmas) was compared to the sterilization methods using gamma and beta radiations. The changes to both the physical and chemical properties of the sterilized exopolysaccharides were analyzed. The use of ethylene oxide can be recommended for the sterilization of polysaccharides as a weak effect on both rheological and structural properties was observed. This low-temperature gas sterilizing process is very efficient, giving a good Sterility Assurance Level (SAL), and is also well suited to large-scale compound manufacturing in the pharmaceutical industry. PMID:21566796

  16. Understanding him in STEM: Sharing the stories of African American male scholars in engineering academic programs at a predominantly White university

    Science.gov (United States)

    Hayes, Robert E., III

    Globalization of the world economy has confirmed the need for citizens to exemplify competitive capacities in science, technology, engineering, and mathematics fields. Since the 1970s, American higher education has seen increasing numbers of students entering college but has witnessed a decline in the number of students enrolling in STEM programs. African American men fall behind other students in regards to academic performance, persistence, and success throughout primary, secondary, and tertiary schooling. Accordingly, participation of African American men in STEM disciplines is low in comparison to White males and other race groups. Various factors have been identified as contributing to the academic failures of Black men. Poor academic and social preparedness, racial identity issues, institutional climates, negative stereotypes, and fear of success have been cited as potential contributors to the relative invisibility of African American men in STEM disciplines. This study explores the life stories of five African American male scholars in the college of engineering at a predominantly white university. The goal of the qualitative investigation is to help university faculty and administrators understand the institutional, interpersonal, and collective mechanisms influencing the success identities of African American male undergraduates in STEM academic programs. Understanding the lived experiences of this population may help universities innovate stronger supports for men of color in college and broaden the borders for all students interested in STEM careers.

  17. The effect of endoscopic sterilization on reproductive behavior and pair bond maintenance of feral pigeons (Columba livia).

    Science.gov (United States)

    Heiderich, E; Failing, K; Lierz, M; Schildger, B

    2016-01-01

    Problems related to feral pigeons (Columba livia) in cities mainly result from their large numbers due to uncontrolled population growth. The aim of this study was to evaluate whether endoscopic guided sterilization affects the reproductive behavior of feral pigeons under experimental conditions, with the intention of assessing this technique as a potential method for feral pigeon population control. Five groups of four pairs of feral pigeons each were studied from 8 weeks before, to 7 weeks after sterilization. Both the male and female of the first pair of each group were sterilized, in the second pair only the female and in the third pair only the male was sterilized. The fourth pair acted as a control. All eggs laid were candled to assess fertility. Surgical sterilization had minimal effects on behavior and therefore seems not to have impact on possible field application for population control. All pairs maintained their pair bonds and continued to defend their nesting sites against other pigeons. Only one female copulated with a foreign fertile male while her primary partner was debilitated due to surgery, but returned to him as soon as he recovered. All eggs laid more than 5 days after male sterilization were infertile, whereas all control pairs had fertile eggs. Only one fertile clutch was produced, 5 days after the male's sterilization. Therefore it is assumed that males remain fertile for a limited period of time. Endoscopic sterilization seems to be a promising method for field control of feral pigeon populations and sterilization of the male only seems sufficient.

  18. Mortality and sterility induced in Piophila casei by x-ray and neutron irradiation

    International Nuclear Information System (INIS)

    Sacchi, L.; Gasperi, G.; Grigolo, A.; Caprotti, M.; Pinelli, T.; Altieri, S.

    1977-01-01

    Different doses of neutrons and X-rays were given to 5-day-old pupae of Piophila casei L. (Diptera, Piophilidae), just before their emergence. The mortality and sterility induced by the different types of radiation were measured. Neutrons are more effective than X-rays in provoking lethal lesions in somatic cells. Females are more resistant than males to the sterilizing action of neutrons, the relative biological efficiency of neutrons being 6 and 3.5, respectively

  19. Sterility of the uterine cavity

    DEFF Research Database (Denmark)

    Møller, Birger R.; Kristiansen, Frank V.; Thorsen, Poul

    1995-01-01

    In a prospective open study the sterility of the uterine cavity was evaluated in 99 women admitted for hysterectomy. The indications for hysterectomy were in most cases persistent irregular vaginal bleeding and fibromyomas of the uterus. Samples for both aerobic and anaerobic bacteria, Chlamydia ...... which may play a causative role in endometritis. The results indicate that inflammation of the uterine cavity should be evaluated by hysteroscopic examination before hysterectomy is undertaken in patients with persistent irregular vaginal bleeding. Udgivelsesdato: 1995-Mar...

  20. Signature of heavy sterile neutrinos at CEPC

    Science.gov (United States)

    Liao, Wei; Wu, Xiao-Hong

    2018-03-01

    We study the production of heavy sterile neutrino N , e+e-→N ν (ν ¯), at the Circular Electron Positron Collider (CEPC) and its l j j signal in its decay to three charged fermions. We study background events for this process which are mainly events coming from W pair production. We study the production of a single heavy sterile neutrino and the sensitivity of CEPC to the mixing of the sterile neutrino with active neutrinos. We study the production of two degenerate heavy sterile neutrinos in a low energy seesaw model by taking into account the constraints on mixings of sterile neutrinos from the neutrinoless double β decay experiment and the masses and mixings of active neutrinos. We show that CEPC under proposal has a good sensitivity to the mixing of sterile neutrinos with active neutrinos for a mass of a sterile neutrino around 100 GeV.

  1. Characterization of Prdm9 in equids and sterility in mules.

    Directory of Open Access Journals (Sweden)

    Cynthia C Steiner

    Full Text Available Prdm9 (Meisetz is the first speciation gene discovered in vertebrates conferring reproductive isolation. This locus encodes a meiosis-specific histone H3 methyltransferase that specifies meiotic recombination hotspots during gametogenesis. Allelic differences in Prdm9, characterized for a variable number of zinc finger (ZF domains, have been associated with hybrid sterility in male house mice via spermatogenic failure at the pachytene stage. The mule, a classic example of hybrid sterility in mammals also exhibits a similar spermatogenesis breakdown, making Prdm9 an interesting candidate to evaluate in equine hybrids. In this study, we characterized the Prdm9 gene in all species of equids by analyzing sequence variation of the ZF domains and estimating positive selection. We also evaluated the role of Prdm9 in hybrid sterility by assessing allelic differences of ZF domains in equine hybrids. We found remarkable variation in the sequence and number of ZF domains among equid species, ranging from five domains in the Tibetan kiang and Asiatic wild ass, to 14 in the Grevy's zebra. Positive selection was detected in all species at amino acid sites known to be associated with DNA-binding specificity of ZF domains in mice and humans. Equine hybrids, in particular a quartet pedigree composed of a fertile mule showed a mosaic of sequences and number of ZF domains suggesting that Prdm9 variation does not seem by itself to contribute to equine hybrid sterility.

  2. Non-surgical methods of contraception and sterilization.

    Science.gov (United States)

    Kutzler, Michelle; Wood, Anna

    2006-08-01

    The Humane Society of the United States estimates that each year between 8 and 10 million dogs and cats enter shelters and 4-5 million of these animals are euthanized due to lack of homes. Many veterinarians within the United States recommend surgical sterilization for population control in dogs and cats. However, there are non-surgical methods to control reproduction. Pharmacologic methods of contraception and sterilization can be safe, reliable and reversible. Hormonal treatments using progestins, androgens, or gonadotropin releasing hormone (GnRH) analogs act to either directly block reproductive hormone receptor-mediated events, or indirectly block conception via negative feedback mechanisms. Immunocontraception, via vaccination against GnRH, the luteinizing hormone receptor or zona pellucida proteins, is also possible. Intratesticular or intraepididymal injections provide a method for non-surgical sterilization of the male dog and cat. Additional methods have been employed for mechanical disruption of fertility including intravaginal and intrauterine devices and ultrasound testicular ablation. Alternative approaches to surgical sterilization will be reviewed.

  3. The efficacy of four gametocides for induction of pollen sterility in ...

    African Journals Online (AJOL)

    Habteab Ghebrehiwot

    2015-02-19

    Feb 19, 2015 ... Effective chemical hybridizing agents (CHAs) or male gametocides enhance cross pollination in plant breeding and genetic analysis ... priate equipment and skilled personnel (Berhe and Miller,. 1976; Ketema, 1997; Gugsa ... The gametocidal property of gibberellic acid in inducing male sterility is also well ...

  4. The development of new radiation protocols for insect sterilization using long wavelength x-rays

    Science.gov (United States)

    Urquidi, Jacob; Brar, Ramaninder K.; Rodriguez, Stacy; Hansen, Immo

    2015-07-01

    Control of insect species for the protection of crops, livestock, and prevention of disease such as dengue fever and malaria is a high priority in today's global economy. Traditional methods such as pesticides have fallen out of favor because its effects are indiscriminate as well as adverse and unpredictable impacts on the environment. Modern novel techniques such as genetic modification have had trouble gaining traction due to ethics concerns and the potential for unforeseen side effects. One approach that has gained traction and has proven its efficacy is the use of ionizing radiation to affect sterility in insect species in order to scale back their population. Known as Sterile Insect Technique (SIT), it has proven very effective in eradicating certain dipteran insect populations. However, when standard sterilization methods developed for dipertans are applied to mosquito populations significant complications arise, such as an inability to compete with non-irradiated males and high mortality rates. We have investigated the effect of treatment with x-rays of different wavelengths on x-ray sterilized mosquito males. Our results have demonstrated that longer wavelength x-rays have a significant effect on the outcome of the sterile males' longevity as well as an increase on the efficacy of sterilization while employing a substantially lower dose.

  5. Sterile Neutrinos in Cold Climates

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Benjamin J.P. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2015-09-01

    Measurements of neutrino oscillations at short baselines contain an intriguing set of experimental anomalies that may be suggestive of new physics such as the existence of sterile neutrinos. This three-part thesis presents research directed towards understanding these anomalies and searching for sterile neutrino oscillations. Part I contains a theoretical discussion of neutrino coherence properties. The open-quantum-system picture of neutrino beams, which allows a rigorous prediction of coherence distances for accelerator neutrinos, is presented. Validity of the standard treatment of active and sterile neutrino oscillations at short baselines is verified, and non-standard coherence loss effects at longer baselines are predicted. Part II concerns liquid argon detector development for the MicroBooNE experiment, which will search for short-baseline oscillations in the Booster Neutrino Beam at Fermilab. Topics include characterization and installation of the MicroBooNE optical system; test-stand measurements of liquid argon optical properties with dissolved impurities; optimization of wavelength-shifting coatings for liquid argon scintillation light detection; testing and deployment of high-voltage surge arrestors to protect TPC field cages; and software development for optical and TPC simulation and reconstruction. Part III presents a search for sterile neutrinos using the IceCube neutrino telescope, which has collected a large sample of atmospheric-neutrino-induced events in the 1-10 TeV energy range. Sterile neutrinos would modify the detected neutrino flux shape via MSW-resonant oscillations. Following a careful treatment of systematic uncertainties in the sample, no evidence for MSW-resonant oscillations is observed, and exclusion limits on 3+1 model parameter space are derived. Under the mixing assumptions made, the 90% confidence level exclusion limit extends to sin224 ≤ 0.02 at m2 ~ 0.3 eV2, and the LSND and Mini

  6. 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.

  7. 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.

  8. 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.

  9. Male circumcision.

    Science.gov (United States)

    2012-09-01

    Male circumcision consists of the surgical removal of some, or all, of the foreskin (or prepuce) from the penis. It is one of the most common procedures in the world. In the United States, the procedure is commonly performed during the newborn period. In 2007, the American Academy of Pediatrics (AAP) convened a multidisciplinary workgroup of AAP members and other stakeholders to evaluate the evidence regarding male circumcision and update the AAP's 1999 recommendations in this area. The Task Force included AAP representatives from specialty areas as well as members of the AAP Board of Directors and liaisons representing the American Academy of Family Physicians, the American College of Obstetricians and Gynecologists, and the Centers for Disease Control and Prevention. The Task Force members identified selected topics relevant to male circumcision and conducted a critical review of peer-reviewed literature by using the American Heart Association's template for evidence evaluation. Evaluation of current evidence indicates that the health benefits of newborn male circumcision outweigh the risks; furthermore, the benefits of newborn male circumcision justify access to this procedure for families who choose it. Specific benefits from male circumcision were identified for the prevention of urinary tract infections, acquisition of HIV, transmission of some sexually transmitted infections, and penile cancer. Male circumcision does not appear to adversely affect penile sexual function/sensitivity or sexual satisfaction. It is imperative that those providing circumcision are adequately trained and that both sterile techniques and effective pain management are used. Significant acute complications are rare. In general, untrained providers who perform circumcisions have more complications than well-trained providers who perform the procedure, regardless of whether the former are physicians, nurses, or traditional religious providers. Parents are entitled to factually correct

  10. Dog and cat management through sterilization: Implications for population dynamics and veterinary public policies.

    Science.gov (United States)

    Dias, Ricardo Augusto; Baquero, Oswaldo Santos; Guilloux, Aline Gil Alves; Moretti, Caio Figueiredo; de Lucca, Tosca; Rodrigues, Ricardo Conde Alves; Castagna, Cláudio Luiz; Presotto, Douglas; Kronitzky, Yury Cezar; Grisi-Filho, José Henrique Hildebrand; Ferreira, Fernando; Amaku, Marcos

    2015-11-01

    The present study aimed to compare different sterilization scenarios allowing the adoption of the most adequate strategy to control owned dog and cat population sizes as the official veterinary public policy for animal control in an urban area of Campinas municipality, Brazil. To achieve this goal, the vital parameters of the owned pet population were measured in a neighborhood of Campinas called Jardim Vila Olimpia through questionnaires used in two census studies performed in February 2012 and June 2013. Different hypothetical sterilization scenarios were compared with the scenario of a single sterilization campaign performed in the study area between the census studies. Using a deterministic mathematical model, population dynamics were simulated for these different scenarios. We have observed that for both owned dogs and cats, the impact on the population size achieved by a single sterilization campaign would be diluted over the years, equating to the impact achieved by the usual sterilization rate practiced before the sterilization campaign yearly. Moreover, using local and global sensitivity analyses, we assessed the relative influence on animal population evolution of each vital parameter used in the mathematical models. The more influential parameters for both species were the carrying capacity of the environment and sterilization rates of males and females (for both species). We observed that even with sterilizing 100% of the intact animals annually, it would not be possible to obtain proportions greater than 86% and 88% of sterilized dogs and cats, respectively, after 20 years due to the high introduction of new intact animals. There is no public dog and cat sterilization service in place in the city, and sporadic and local sterilization campaigns are performed with a prior communication to the owners to bring their animals to be sterilized in a selected veterinary facility. If a sterilization campaign was performed annually in the study area, it would

  11. Experimental bounds on sterile neutrino mixing angles

    CERN Document Server

    Ruchayskiy, Oleg

    2012-01-01

    We derive bounds on the mixing between the left-chiral ("active") and the right-chiral ("sterile") neutrinos, provided from the combination of neutrino oscillation data and direct experimental searches for sterile neutrinos. We demonstrate that the mixing of sterile neutrinos with any flavour can be significantly suppressed, provided that the angle theta_13 is non-zero. This means that the lower bounds on sterile neutrino lifetime, coming from the negative results of direct experimental searches can be relaxed (by as much as the order of magnitude at some masses). We also demonstrate that the results of the negative searches of sterile neutrinos with PS191 and CHARM experiments are not applicable directly to the see-saw models. The reinterpretation of these results provides up to the order of magnitude stronger bounds on sterile neutrino lifetime than previously discussed in the literature. We discuss the implications of our results for the Neutrino Minimal Standard Model (the NuMSM).

  12. 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.

  13. Surgical Sterilization, Regret, and Race: Contemporary Patterns*

    Science.gov (United States)

    Shreffler, Karina M.; McQuillan, Julia; Greil, Arthur L.; Johnson, David R.

    2014-01-01

    Surgical sterilization is a relatively permanent form of contraception that has been disproportionately used by Black, Hispanic, and Native American women in the United States in the past. We use a nationally representative sample of 4,609 women ages 25 to 45 to determine whether sterilization continues to be more common and consequential by race for reproductive-age women. Results indicate that Native American and Black women are more likely to be sterilized than non-Hispanic White women, and Hispanic and Native American women are more likely than non-Hispanic White women to report that their sterilization surgeries prevent them from conceiving children they want. Reasons for sterilization differ significantly by race. These findings suggest that stratified reproduction has not ended in the United States and that the patterns and consequences of sterilization continue to vary by race. PMID:25592919

  14. Surgical sterilization, regret, and race: contemporary patterns.

    Science.gov (United States)

    Shreffler, Karina M; McQuillan, Julia; Greil, Arthur L; Johnson, David R

    2015-03-01

    Surgical sterilization is a relatively permanent form of contraception that has been disproportionately used by Black, Hispanic, and Native American women in the United States in the past. We use a nationally representative sample of 4592 women ages 25-45 to determine whether sterilization continues to be more common and consequential by race for reproductive-age women. Results indicate that Native American and Black women are more likely to be sterilized than non-Hispanic White women, and Hispanic and Native American women are more likely than non-Hispanic White women to report that their sterilization surgeries prevent them from conceiving children they want. Reasons for sterilization differ significantly by race. These findings suggest that stratified reproduction has not ended in the United States and that the patterns and consequences of sterilization continue to vary by race. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Development and Validation of Sterility Systems for Trees

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, Steve; Shevchenko, Olga; Ma, Caiping (Cathleen)

    2007-03-30

    The overall goal of this project was to develop and validate sterility systems in poplar with the ultimate goal of fulfilling the basic requirements for commercial use. For this, sterility must be complete and stable over multiple growing seasons, cause no detrimental effects on vegetative growth, and successful transformation events must be identifiable via molecular tests when trees are still juvenile. Because of the inherent difficulties in achieving and demonstrating complete sterility in trees, our approach was to study alternate sterility systems in Arabidopsis and/or early-flowering tree systems. The public benefit from this work is the capacity for containment of genes or exotic forms of trees so they can be of benefit for industry for production of wood, energy, and renewable products, while having minimal impact on wild populations of trees. We tested three methods for engineering sterility: dominant negative mutant (DNM) proteins, floral tissue ablation, and RNA interference (RNAi) to suppress the expression of several floral regulatory genes. The ultimate goal of this work was to produce a number of transgenic poplars that could be outplanted to enable future assessments of the effectiveness of these transgenic sterility methods. Our attempts to produce ablation constructs that did not interfere with tree health were partially successful. Using the poplar LEAFY gene promoter and the barnase/barstar system, we were able to regenerate plants that grew well in the greenhouse, but they showed poor health in the field. Four of seven DNM genes tested were considered promising enough, based on results in Arabidopsis, to produce transgenic poplars. Single, double, and triple RNAi genes were produced and transformed into poplar. Over all, we produced 1,964 PCR-confirmed transgenic events with 19 different kinds of sterility genes and several kinds of control genes. We propagated 5,640, 6,820, and 7,055 trees for each of three test poplar genotypes, and field

  16. EB surface sterilization of food material

    International Nuclear Information System (INIS)

    Kaneko, H.; Mizutani, A.; Kato, K.; Nishikimi, T.; Taniguchi, S.

    2001-01-01

    In this paper, we introduce a food irradiation with low energetic, lower than 300keV, electrons (so-called SOFT ELECTRON) as a rather new method of food sterilization. It is also a physical sterilization method, and free from the problems mentioned above. Low energetic electrons have small penetration power (50-200micron) through raw materials, and by selecting a proper energy of electrons we can sterilize only the surfaces or skins of target materials

  17. "We never thought of a vasectomy": a qualitative study of men and women's counseling around sterilization.

    Science.gov (United States)

    Shih, Grace; Dubé, Kate; Dehlendorf, Christine

    2013-09-01

    Sterilization is the most commonly used method of contraception in the United States; however, little is known about how providers counsel about these procedures or the information patients desire. In this study, we explore male and female experiences of sterilization counseling and their perspectives on ideal sterilization counseling. In-depth individual and group interviews were conducted with 37 heterosexual couples between the ages of 25 and 55 years. Each couple had reached their desired family size. Interviews were recorded and transcribed using NVivo software and analyzed using modified grounded theory. Men and women differed in their experiences of sterilization counseling. Women commonly received counseling on female sterilization but not vasectomy, while men rarely discussed either form of sterilization with their providers. Both men and women desired more information about sterilization. Contraceptive counseling of couples who have completed childbearing does not routinely include men or the option of vasectomy, despite the advantages of this method with respect to safety, efficacy and cost. Family planning and primary care providers have an important role in ensuring that couples are aware of all their options and can make an informed decision about their contraception. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. First results in the use of sterile insect technique against Trialeurodes vaporariorum (Homoptera: Aleyroididae) in greenhouses

    International Nuclear Information System (INIS)

    Calvitti, M.; Remotti, P.C.; Pasquali, A.; Cirio, U.

    1998-01-01

    Trials for the evaluation of the effectiveness of the sterile insect technique for the suppression of greenhouse whitefly, Trialeurodes vaporariorum (Westwood), both in cage and in greenhouse conditions are described. The results show a significant reduction of the reproductive capacity of the untreated whitefly populations interacting with sterile insects. Untreated whiteflies, co-existing in a mixed population together with sterile insects, attained less than the half (44%) of their potential reproductive capacity. This trend was also evident in the cage test where the untreated whitefly population, crossed with the sterile whiteflies, increased without exceeding 2/3 of the density recorded in the control cages. These results may be based on 2 joint sterile insect technique effects: primarily a drastic reduction of the progeny of normal untreated females, when mating with sterile males, carriers of dominant lethal mutations, and secondarily a progressive reduction of the females in the population due to an increasing rate of unsuccessful matings resulting in a condition of forced arrhenotoky. No deleterious effects, on plant health and fruit quality, were observed on plants exposed to high sterile whitefly pressures

  19. (SSR) markers for non-pollen type thermo-sensitive genic male

    African Journals Online (AJOL)

    sensitive genic male sterility (TGMS) lines. In this study, a TGMS line showing non-pollen type thermo-sensitive genic male sterility was used. Crossing between TGMS line (female parent) and normal pollen varieties; CNT1 and PTT1 (male parent) ...

  20. Sterilization of oils: Data to support the use of a continuous point-of-use sterilizer.

    Science.gov (United States)

    Bader, F G; Boekeloo, M K; Graham, H E; Cagle, J W

    1984-08-01

    The continuous slow feed of animal and vegetable oils is frequently found to be an economically attractive method for maintaining antibiotic fermentations at a highly productive rate. The sterilization of oil feeds can present a major problem in the production plant. In this article, we present data and methodology on the kinetics of the thermal sterilization of No. 2 lard oil and soybean oil. It was also determined that dry heat sterilization condition could occur if dry spores were added to dry oil. This condition could only be partially alleviated by the addition of water to the oil. The theory and design of a small tubular coil continuous sterilizer for sterilizing oils at the point of use is also presented. This type of sterilizer is economical and versatile and simplifies control and instrument requirements. It provides a realistic alternative to the use of sterile feed tanks and sterile headers.

  1. 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

  2. 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)

  3. 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.

  4. 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.

  5. Seeking sterile neutrinos in Finslerian cosmology

    Science.gov (United States)

    Wang, Deng; Meng, Xin-He

    2017-11-01

    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_0 tension more effectively than the other three models. For the Finslerian massless sterile neutrino model, we obtain the constraint N_eff=3.237^{+0.092}_{-0.185}, which is consistent with Δ N_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_eff=3.143^{+0.064}_{-0.066}, which favors Δ N_eff > 0 at the 1.47σ CL, and m_{ν , sterile}^eff 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.

  6. Inherited sterility in Eldana saccharina Walker (Lepidoptera: Pyralidae): effect of sub-sterilizing doses of gamma radiation on mating, fecundity and fertility

    International Nuclear Information System (INIS)

    Annoh, C.E.; Adabie-Gomez, D.A. Biotechnology and Nuclear Agriculture Research Institute; Botchey, M.A.; Mensah, B.A.

    2003-01-01

    Mature pupae (6-8 days old) of Eldana saccharina were exposed to increasing sub-sterilizing doses of ionizing gamma radiation in the range of 80-180 Gy. In the parental (P) generation, emerged male and female moths were out-crossed with untreated moths of the opposite sex. Reciprocal crosses between progeny of treated and untreated moths were also made in the F1 generation. In both generations, radiation doses used did not have any significant effect on mating behaviour of adults E. saccharina. There was also no significant difference in the mean number of spermatophores (approximately 1.0 per female) transferred by males to females during copulation among treated and control crosses. Fecundity in the parental generation was reduced by 40-44% in crosses between treated males and untreated females without any clear dose dependence. In the reciprocal crosses, however, fecundity considerably decreased with the increasing dose of radiation. The dose-dependent decreased of fecundity, similar in both reciprocal crosses, was also observed in F1 generation. Increasing doses of radiation generally resulted in decreasing fertility of treated moths in both the P and F1 generations. There was, however, a remarkable difference between reciprocal crosses. While radiation induced only partial sterility of treated P males even at the highest dose (180 Gy), treated P females exhibited a high sterility at 100 Gy. In both F1 crosses, fertility was lower than in treated P males, and F1 males exhibited a higher level of inherited sterility than F1 females. The results demonstrate a potential of using inherited sterility in integrated pest management programme to suppress the pest population of E. saccharina and other related stemborer species (author)

  7. Factors affecting the efficiency of the sterile insect release method for tsetse

    International Nuclear Information System (INIS)

    Curtis, C.F.

    1980-01-01

    Data are reviewed on the levels of sterility, survival and competitiveness of Glossina males after irradiation with various gamma-ray doses delivered in air or nitrogen. A simple population model helps in the choice of the optimum dose. Field studies of mating competitiveness require a measure of the ratio of sterile to fertile males and of sterile to fertile matings, and both ratio estimates will be subject to sampling error. Data on multiple mating of female Glossina are reviewed. There is some degree of precedence for sperm from the first mating but sterile sperm are fully competitive for fertilization and, following the early death of an embryo, the timing of the next ovulation is only advanced to a slight extent. Thus in an isolated population the occurrence or non-occurrence of female polygamy would be of almost no consequence. Where mated females were immigrating into the release area female polygamy would be advantageous. The low recovery potential of tsetse populations is the main reason for thinking them suitable for control by the introduction of sterility. In trying to measure this recovery potential it is important to distinguish it from natural seasonal increase. If natural population fluctuations are studied to detect density dependent effects it is important not to confuse cause with effect. Non-isolation of the 'target' population is almost certainly the most serious obstacle to practical application of the sterile insect release method, and a steady 'rolling forward' of the release area may be a possible solution. (author)

  8. The development of new radiation protocols for insect sterilization using long wavelength x-rays

    Energy Technology Data Exchange (ETDEWEB)

    Urquidi, Jacob, E-mail: jurquidi@nmsu.edu; Brar, Ramaninder K. [X-ray and Neutron Science Laboratory, Department of Physics, New Mexico State University, Las Cruces, NM (United States); Rodriguez, Stacy; Hansen, Immo [Molecular Vector Physiology Lab, Department of Biology, New Mexico State University, Las Cruces, NM (United States)

    2015-07-23

    Control of insect species for the protection of crops, livestock, and prevention of disease such as dengue fever and malaria is a high priority in today’s global economy. Traditional methods such as pesticides have fallen out of favor because its effects are indiscriminate as well as adverse and unpredictable impacts on the environment. Modern novel techniques such as genetic modification have had trouble gaining traction due to ethics concerns and the potential for unforeseen side effects. One approach that has gained traction and has proven its efficacy is the use of ionizing radiation to affect sterility in insect species in order to scale back their population. Known as Sterile Insect Technique (SIT), it has proven very effective in eradicating certain dipteran insect populations. However, when standard sterilization methods developed for dipertans are applied to mosquito populations significant complications arise, such as an inability to compete with non-irradiated males and high mortality rates. We have investigated the effect of treatment with x-rays of different wavelengths on x-ray sterilized mosquito males. Our results have demonstrated that longer wavelength x-rays have a significant effect on the outcome of the sterile males’ longevity as well as an increase on the efficacy of sterilization while employing a substantially lower dose.

  9. The development of new radiation protocols for insect sterilization using long wavelength x-rays

    International Nuclear Information System (INIS)

    Urquidi, Jacob; Brar, Ramaninder K.; Rodriguez, Stacy; Hansen, Immo

    2015-01-01

    Control of insect species for the protection of crops, livestock, and prevention of disease such as dengue fever and malaria is a high priority in today’s global economy. Traditional methods such as pesticides have fallen out of favor because its effects are indiscriminate as well as adverse and unpredictable impacts on the environment. Modern novel techniques such as genetic modification have had trouble gaining traction due to ethics concerns and the potential for unforeseen side effects. One approach that has gained traction and has proven its efficacy is the use of ionizing radiation to affect sterility in insect species in order to scale back their population. Known as Sterile Insect Technique (SIT), it has proven very effective in eradicating certain dipteran insect populations. However, when standard sterilization methods developed for dipertans are applied to mosquito populations significant complications arise, such as an inability to compete with non-irradiated males and high mortality rates. We have investigated the effect of treatment with x-rays of different wavelengths on x-ray sterilized mosquito males. Our results have demonstrated that longer wavelength x-rays have a significant effect on the outcome of the sterile males’ longevity as well as an increase on the efficacy of sterilization while employing a substantially lower dose

  10. Use of gamma irradiation and inert gases in the sterilization of Ceratitis capitata (Wiedemann, 1824) (Diptera-Tephritidae) with the objective of using the sterile insect technique

    International Nuclear Information System (INIS)

    Almeida, M.S.-P. de.

    1983-11-01

    The sterilization of Ceratitis capitata (Wied., 1824) (Dip. Tephritidae) using gamma irradiation (γ) was studied under laboratory conditions at Center for Nuclear Energy in Agriculture (CENA), Piracicaba, Sao Paulo, Brazil. Living conditions for Med fly are optimum in this country and its biological cycle is completed in less than 30 days. There is a large number of varying host fruits for larvae development, which makes this pest very harmful, especially to citrus crops. The sterile insect technique (SIT) is a type of physical control of pests, which does not cause any harm to other insects. Pupae with different ages were initially submitted to 0, 30, 40, 50, 60, 70, 80 and 90 Gy doses. Sterility was determined from fertility of eggs resulting from crosses of irradiated male x normal female and normal male x irradiated female. Later, pupae with 72 + - 12 hrs before emergence were submitted to 70 and 90 Gy doses with carbon dioxide, nitrogen and oxygen fluxes. The sterilizing dose for the males was 90 Gy. Activity, of irradiated with and without gas lux and normal male, was evaluated with an activity-meter, and the dose least harmful to their behaviour was found to be 90 Gy with nitrogen flux. (Author) [pt

  11. Light Sterile Neutrinos: A White Paper

    DEFF Research Database (Denmark)

    Abazajian, K. N.; Acero, M. A.; Agarwalla, S. K.

    2012-01-01

    This white paper addresses the hypothesis of light sterile neutrinos based on recent anomalies observed in neutrino experiments and the latest astrophysical data.......This white paper addresses the hypothesis of light sterile neutrinos based on recent anomalies observed in neutrino experiments and the latest astrophysical data....

  12. Sodium hypochlorite sterilization of culture medium in ...

    African Journals Online (AJOL)

    With the purpose of finding an alternative to thermal sterilization, this research aimed at assessing the efficiency and ideal concentration of sodium hypochlorite for sterilization of culture media and glassware used during rooting of micropropagated Gerbera hybrida cv. Essandre. Two experiments were carried out. In the first ...

  13. 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...

  14. Las representaciones sociales sobre la esterilización masculina. El punto de vista de los orientadores del servicio de vasectomía en la Clínica del Hombre, en Bogotá, Colombia Social representations of male sterilization. Vasectomy as viewed by professional counselors at the Men's Clinic in Bogotá, Colombia

    Directory of Open Access Journals (Sweden)

    Mara Viveros

    1998-01-01

    Full Text Available Los oferentes del servicio de vasectomía en la Clínica del Hombre, en Bogotá, construyen sus representaciones sobre este método anticonceptivo con base en un discurso biomédico, en su interacción con el usuario y en sus propias experiencias de vida. En la oferta del servicio, los orientadores tienen el mayor contacto con los usuarios. Son los encargados de indagar los motivos para solicitar el servicio y dar información que permita tomar una decisión con tranquilidad y certeza. Adicionalmente, son quienes, de manera directa, filtran la demanda del servicio a partir de sus experiencias, conocimientos y destrezas. Esto, conforme a una permanente negociación que realizan entre los criterios institucionales (número y espaciamiento de los hijos, edad del cliente, estabilidad de la pareja y grado de seguridad en la decisión, y su percepción y valoración del usuario. Las representaciones de los orientadores estudiados sobre la toma de decisión de la vasectomía muestran que es presentada, por una parte, como un método fácil e inofensivo y, por otra, como una opción de planificación liberadora.Vasectomy service providers at the Clínica del Hombre (Men's Clinic in Bogotá, Colombia, construct their representations concerning male sterilization on the basis of biomedical discourse, their interaction with clinic users, and their own life experiences. During provision of such services, the counselors are the health professionals who have the closest contact with these clients of the clinic. Counselors are in charge of exploring their motivations in requesting the service, in addition to providing information allowing them to take a calm, sound decision. They also directly filter demand based on their experience, knowledge, and skills, in permanent negotiation between institutional criteria (number of children and gap between them, client's age, steadiness of couple's relationship, and conviction concerning the decision, and their

  15. Iran eases limits on sterilization.

    Science.gov (United States)

    Roudi, N

    1991-03-01

    The government of Iran announced in November 1990, in an abrupt reversal of previous policies, the legislation of sterilization and its provision free-of-charge upon request, as well as the distribution of other contraceptive gratis. At the time of the Islamic Revolution in 1979 the government adopted a pronatalist policy, family planning programs were interrupted, legal ages of marriage were lowered, and barriers against polygamy were loosened. Iran had a 3.5% growth rate in 1990 and a total fertility rate of 6.3 lifetime births/woman. After the end of the war between Iran and Iraq in 1988, the population explosion became an obstacle to reconstruction. In 1950, the population numbered 14.2 million; by 1970 it had doubled to 28.4 million. In 1990, the country had 54.6 million people. According to a 1990 UN assessment the population will soar to 100 million by 2020. Over 8 million live in Tehran where overcrowding, traffic congestion, air pollution, and high living costs are the norm. the 1989 National Birth Control Policy Summary adopted targets to reduce the average number of lifetime births per woman to 4 children and natural growth rate to 2.3% by 2011, and to provide family planning to 24% of reproductive-age women whereby 1 million conceptions would be prevented. Indirect measures to curb fertility include raising literacy promoting the education of girls, improving the status and health conditions of women, and reducing maternal and child mortality. A media campaign has started to encourage a small family model. The low legal, social, educational, and employment status of women poses obstacles to this plan, however, the revision of laws that conflict with these goals has been urged. In other Islamic countries such as Turkey, Tunisia, Indonesia, Pakistan, and Bangladesh, female sterilization is legal. Abortion in Iran remains banned except for saving the life of the mother.

  16. Federally funded sterilization: time to rethink policy?

    Science.gov (United States)

    Borrero, Sonya; Zite, Nikki; Creinin, Mitchell D

    2012-10-01

    In the 1970s, concern about coercive sterilization of low-income and minority women in the United States led the US Department of Health, Education, and Welfare to create strict regulations for federally funded sterilization procedures. Although these policies were instituted to secure informed consent and protect women from involuntary sterilization, there are significant data indicating that these policies may not, in fact, ensure that consent is truly informed and, further, may prevent many low-income women from getting a desired sterilization procedure. Given the alarmingly high rates of unintended pregnancy in the United States, especially among low-income populations, we feel that restrictive federal sterilization policies should be reexamined and modified to simultaneously ensure informed decision-making and honor women's reproductive choices.

  17. Studies of the ecology of insects sterilized artificially (gamma radiation), 10

    International Nuclear Information System (INIS)

    Kiyoku, Masao

    1976-01-01

    Progenies of a combination, T#male# x T#female# (a dose of 2.5 KR from 137 Cs), showed a striking inherited sterility until the fourth generation when the mating was made between inbred lines of the combination. In combinations that irradiated flies were crossed as either male or female with unirradiated ones, some inherited sterility was found in the first and second generations, and was almost entirely disappeared after the third of fourth generation. However, conspicuous inherited sterility was maintained through thirteen generations when progeny flies from the combination of T#male# x U#female#, which was irradiated by a dose of 7.5 KR, were inbred. From cytological studies, it is observed that the oriental fruit fly has chromosome number of n=6 both in salivary gland cells and in meiotic division. An amitosis like cell division occured among meiotic cells of irradiated male flies and those of male progenies that had been mated with unirradiated females. Several different types of chromosome aberrations were found frequently in the salivary gland chromosomes of flies showing inherited sterility. By statistical analysis, the relationship between the second power of frequency (X) of the chromosome aberration and hatchability (Y) of eggs laid was showed to be a straight regression equation, Y=40.69 - (X - 18.75)*. The correlation-coefficient (r), -867* was obtained. (auth.)

  18. 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)

  19. Sterile insect technique: new technology to control fruit flies, Ceratitis capitata, in the Lower Basin of the Sao Francisco Valley

    International Nuclear Information System (INIS)

    Paranhos, Beatriz Aguiar Jordao; Barbosa, Flavia Rabelo; Nascimento, Antonio Souza do; Viana, Rodrigo; Malavasi, Aldo; Sampaio, Raimundo; Walder, Julio Marcos Melges

    2008-01-01

    The SIT is the creation, on a large scale, the insect-pest to be controlled and weekly release of these insects sterilized in the field.The sterile insects copulate with the wild, but do not generate descendants. The basic premises for the use of SIT in insect control are: the reproduction is through sexual intercourse, the female copulate preferably only once there is ease of creation of the plague in industrial scale in artificial diet. The efficiency of the SIT may be greater when only the males are released in the field because they increase the probability of copulating with wild females only, with reductions in the cost of production and release. In the case of fruit-flies, sterile females continue doing puncture in the fruits, which decreases the quality for export. To be able to release only males in the field, in 1980s, was developed a mutant strain, whose females emerge from pupae white, thus being able to discard the white ones, keeping the pupae Brown for the release of sterile males. Ten years after, to save on the industrial scale production system, was obtained a mutant whose females possess lethal temperature sensitivity of 34 deg C, still in the embryo stage. Then the eggs are placed on artificial diet, and when they arrive at the pupa stage, they are all brown and males. Forty-eight to 24 hours before the emergence of adults, the pupae are painted with fluorescent powder paint, bagged and irradiated with gamma radiation of 95Gy of Co-60 or X-ray. As soon as the males emerge, are marked with fluorescent ink and when they reach 3 to 5 days old, are released into the field. Thus, when monitoring is done in Jackson traps in the field, it is possible to distinguish wild male sterile under black light or epifluorescence microscope with males, because the sterile are fluorescent. On application of the SIT to Moscamed, sterile males are released in the field must display good dispersibility, good survival and good sexual performance. The efficiency and

  20. Sterile insect technique for tsetse control and eradication

    International Nuclear Information System (INIS)

    1990-01-01

    The current publication contains the contributions made by scientists who participated in the fourth Co-ordinated Research Programme. A range of topics, covering both field and laboratory activities, was addressed: Eradication of Glossina palpalis palpalis (Robineau-Desvoidy) (Diptera: Glossinidae) from agropastoral land in Central Nigeria by means of the sterile insect technique; Research and development in the IAEA Laboratory at Seibersdorf in support of BICOT for the eradication of Glossina palpalis palpalis; Tsetse fly eradication in Burkina Faso and evaluation of traps and targets; Ecology of Glossina species inhabiting peridomestic agroecosystems in relation to options for tsetse fly control; Population dynamics of Glossina fuscipes fuscipes on Buvuma Island, Lake Victoria, Uganda; Population estimation from mark-recapture data: Equations for a pooled mark system and for pooled data, with applications to a study on island populations of tsetse flies in Zimbabwe; Surveillance of tsetse fly and cattle populations for trypanosomes in the BICOT area during the sterile insect technique control programme; Freeze dried blood and development of an artificial diet for blood feeding anthropods; Effects of the nutritional quality of locally obtained blood diets on the performance of Glossina palpalis palpalis fed in vitro; Mycetomes and symbionts of tsetse flies maintained on a membrane feeding system and the agents interfering with natural reproduction; Virus particles infection in laboratory reared Glossina pallidipes Austen (Diptera: Glossinidae); Influence of different nutritional sources on haemolymph composition and vitellogenesis in haematophagous arthropods; Effect of rearing diet on the injection rate in flies released for the control of tsetse populations by sterile males; Use of juvenile hormone mimics in the sterilization of tsetse flies; Studies of Glossina pallidipes and G. morsitans subspecies related to the genetic control of tsetse flies

  1. Preparatory selection of sterilization regime for canned Natural Atlantic Mackerel with oil based on developed mathematical models of the process

    Directory of Open Access Journals (Sweden)

    Maslov A. A.

    2016-12-01

    Full Text Available Definition of preparatory parameters for sterilization regime of canned "Natural Atlantic Mackerel with Oil" is the aim of current study. PRSC software developed at the department of automation and computer engineering is used for preparatory selection. To determine the parameters of process model, in laboratory autoclave AVK-30M the pre-trial process of sterilization and cooling in water with backpressure of canned "Natural Atlantic Mackerel with Oil" in can N 3 has been performed. Gathering information about the temperature in the autoclave sterilization chamber and the can with product has been carried out using Ellab TrackSense PRO loggers. Due to the obtained information three transfer functions for the product model have been identified: in the least heated area of autoclave, the average heated and the most heated. In PRSC programme temporary temperature dependences in the sterilization chamber have been built using this information. The model of sterilization process of canned "Natural Atlantic Mackerel with Oil" has been received after the pre-trial process. Then in the automatic mode the sterilization regime of canned "Natural Atlantic Mackerel with Oil" has been selected using the value of actual effect close to normative sterilizing effect (5.9 conditional minutes. Furthermore, in this study step-mode sterilization of canned "Natural Atlantic Mackerel with Oil" has been selected. Utilization of step-mode sterilization with the maximum temperature equal to 125 °C in the sterilization chamber allows reduce process duration by 10 %. However, the application of this regime in practice requires additional research. Using the described approach based on the developed mathematical models of the process allows receive optimal step and variable canned food sterilization regimes with high energy efficiency and product quality.

  2. Modelling the effects of the sterile insect technique applied to Eldana saccharina Walker in sugarcane

    Directory of Open Access Journals (Sweden)

    L Potgieter

    2012-12-01

    Full Text Available A mathematical model is formulated for the population dynamics of an Eldana saccharina Walker infestation of sugarcane under the influence of partially sterile released insects. The model describes the population growth of and interaction between normal and sterile E.saccharina moths in a temporally variable, but spatially homogeneous environment. The model consists of a deterministic system of difference equations subject to strictly positive initial data. The primary objective of this model is to determine suitable parameters in terms of which the above population growth and interaction may be quantified and according to which E.saccharina infestation levels and the associated sugarcane damage may be measured. Although many models have been formulated in the past describing the sterile insect technique, few of these models describe the technique for Lepidopteran species with more than one life stage and where F1-sterility is relevant. In addition, none of these models consider the technique when fully sterile females and partially sterile males are being released. The model formulated is also the first to describe the technique applied specifically to E.saccharina, and to consider the economic viability of applying the technique to this species. Pertinent decision support is provided to farm managers in terms of the best timing for releases, release ratios and release frequencies.

  3. 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.)

  4. 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.

  5. Chemical sterilization of allograft dermal tissues.

    Science.gov (United States)

    Phipps, Abigail; Vaynshteyn, Edward; Kowalski, John B; Ngo, Manh-Dan; Merritt, Karen; Osborne, Joel; Chnari, Evangelia

    2017-12-01

    Common terminal sterilization methods are known to alter the natural structure and properties of soft tissues. One approach to providing safe grafts with preserved biological properties is the combination of a validated chemical sterilization process followed by an aseptic packaging process. This combination of processes is an accepted method for production of sterile healthcare products as described in ANSI/AAMI ST67:2011. This article describes the validation of the peracetic acid and ethanol-based (PAAE) chemical sterilization process for allograft dermal tissues at the Musculoskeletal Transplant Foundation (MTF, Edison, NJ). The sterilization capability of the PAAE solution used during routine production of aseptically processed dermal tissue forms was determined based on requirements of relevant ISO standards, ISO 14161:2009 and ISO 14937:2009. The resistance of spores of Bacillus subtilis, Clostridium sporogenes, Mycobacterium terrae, Pseudomonas aeruginosa, Enterococcus faecium, and Staphylococcus aureus to the chemical sterilization process employed by MTF was determined. Using a worst-case scenario testing strategy, the D value was calculated for the most resistant microorganism, Bacillus. The 12D time parameter determined the minimum time required to achieve a SAL of 10 -6 . Microbiological performance qualification demonstrated a complete kill of 10 6 spores at just a quarter of the full cycle time. The validation demonstrated that the PAAE sterilization process is robust, achieves sterilization of allograft dermal tissue to a SAL 10 -6 , and that in combination with aseptic processing secures the microbiological safety of allograft dermal tissue while avoiding structural and biochemical tissue damage previously observed with other sterilization methods such as ionizing irradiation.

  6. Sterilization for Women and Men

    Science.gov (United States)

    ... semen to become totally free of sperm. A couple must use another method of birth control or ... child. Scrotum: The external genital sac in the male that contains the testes. Semen: The fluid made ...

  7. Microscope sterility during spine surgery.

    Science.gov (United States)

    Bible, Jesse E; O'Neill, Kevin R; Crosby, Colin G; Schoenecker, Jonathan G; McGirt, Matthew J; Devin, Clinton J

    2012-04-01

    Prospective study. Assess the contamination rates of sterile microscope drapes after spine surgery. The use of the operating microscope has become more prevalent in certain spine procedures, providing superior magnification, visualization, and illumination of the operative field. However, it may represent an additional source of bacterial contamination and increase the risk of developing a postoperative infection. This study included 25 surgical spine cases performed by a single spine surgeon that required the use of the operative microscope. Sterile culture swabs were used to obtain samples from 7 defined locations on the microscope drape after its use during the operation. The undraped technician's console was sampled in each case as a positive control, and an additional 25 microscope drapes were swabbed immediately after they were applied to the microscope to obtain negative controls. Swab samples were assessed for bacterial growth on 5% sheep blood Columbia agar plates using a semiquantitative technique. No growth was observed on any of the 25 negative control drapes. In contrast, 100% of preoperative and 96% of postoperative positive controls demonstrated obvious contamination. In the postoperative group, all 7 sites of evaluation were found to be contaminated with rates of 12% to 44%. Four of the 7 evaluated locations were found to have significant contamination rates compared with negative controls, including the shafts of the optic eyepieces on the main surgeon side (24%, P = 0.022), "forehead" portion on both the main surgeon (24%, P = 0.022) and assistant sides (28%, P = 0.010), and "overhead" portion of the drape (44%, P = 0.0002). Bacterial contamination of the operative microscope was found to be significant after spine surgery. Contamination was more common around the optic eyepieces, likely due to inadvertent touching of unsterile portions. Similarly, all regions above the eyepieces also have a propensity for contamination because of unknown contact

  8. Dosimetry requirements derived from the sterilization standards

    DEFF Research Database (Denmark)

    Miller, A.

    1998-01-01

    The main standards for radiation sterilization, ISO 11137 and EN 552, rest the documentation for the properly executed sterilization process on dosimetry. Both standards describe general requirements to the dosimetry system: The dose measurements must be traceable to national standards......, the uncertainty of the dose measurement and the environmental influences must be known. This paper discusses how to obtain and maintain traceability and how to document measurement uncertainty. The implications of these requirements in the process control of radiation sterilization are further discussed. Known...

  9. Spore-Forming Bacteria that Resist Sterilization

    Science.gov (United States)

    LaDuc, Myron; Venkateswaran, Kasthuri

    2003-01-01

    A report presents a phenotypic and genotypic characterization of a bacterial species that has been found to be of the genus Bacillus and has been tentatively named B. odysseensis because it was isolated from surfaces of the Mars Odyssey spacecraft as part of continuing research on techniques for sterilizing spacecraft to prevent contamination of remote planets by terrestrial species. B. odysseensis is a Gram-positive, facultatively anaerobic, rod-shaped bacterium that forms round spores. The exosporium has been conjectured to play a role in the elevated resistance to sterilization. Research on the exosporium is proposed as a path toward improved means of sterilization, medical treatment, and prevention of biofouling.

  10. Signatures of extra dimensional sterile neutrinos

    Directory of Open Access Journals (Sweden)

    Werner Rodejohann

    2014-10-01

    Full Text Available We study a large extra dimension model with active and sterile Dirac neutrinos. The sterile neutrino masses stem from compactification of an extra dimension with radius R and are chosen to have masses around eV or keV, in order to explain short-baseline anomalies or act as warm dark matter candidates. We study the effect of the sterile neutrino Kaluza–Klein tower in short-baseline oscillation experiments and in the beta spectrum as measurable by KATRIN-like experiments.

  11. Observations on female sterilization in Chile.

    Science.gov (United States)

    Menanteau-Horta, D

    1982-01-01

    Prior to 1976, voluntary female sterilization was 1 of the regular family planning services offered in Chile. After that the Ministry of Public Health declared that it could not be considered a fertility regulation activity and could thus be performed only for health reasons. Between 1971-75, there was almost a 6-fold increase in the number of sterilizations performed at the Valdivia Regional Hospital, with a rise to 2400 procedures. Such an unprecedented increase in voluntary sterilization prompted this study. The results are based on a 1976 survey of women sterilized between 1971-75 at the Valdivia Regional Hospital. Personal interviews were conducted. The number of voluntary sterilizations there during the aforementioned period showed a sustained upward trend; the number of births increased only moderately during that time. The data on sterilization in the Valdivia area is compared to that collected by the Santiago study. Age, marital status, place of origin or residence, education, and religion were compared. Socioeconomic and occupational data were also examined. 9 of 10 women in Valdivia were from low-income families. This agrees closely with the Santiago data. About 1/4 of the women in both samples were employed outside the home. Also in both samples, about 1/2 of the spouses of sterilized women were blue collar workers; only 1/5 or less were white collar, and very few were professionals. About 52% in Valdivia and 45% in Santiago had borne 7 or more viable offspring. The average number of spontaneous abortions was also similar. A significantly higher percentage (P0.01) of Valdivia women used contraceptives. There are some general trends apparent in both groups as to the reasons for sterilization; most were prompted by difficult socioeconomic conditions. 37.9% of the Santiago women felt their families were complete and 27.3% of the other group cited the same reason. Other reasons were medical, failure of contraception, problems with spouse, and other. Medical

  12. Radiation induced F1 sterility in diamondback moth, Plutella xylostella L., and tropical army worm, Spodoptera litura F

    International Nuclear Information System (INIS)

    Sutrisno, S.; Hoedaya, M.S.; Sutardji, D.; Rahayu, A.

    1993-01-01

    A 300 Gy dose of gamma irradiation can be used as the sterilizing dose for the diamond-back moth (DBM). This caused 90% sterility of the moths. Releases of irradiated moths into the normal populations (nine irradiated to one normal) in laboratory cages, field cages and small field plots reduced the F 1 population by 61, 55 and 42%, respectively. The effects of substerilizing doses of 175 and 200 Gy to the irradiated parents caused 26 and 36% sterilities, respectively. The dose of 175 Gy caused the levels of sterility of the male and female F 1 progeny to be 54 and 74%, respectively, while the dose of 200 Gy caused 56% sterility of the F 1 male and 71% of the F 1 female. The sterility of the F 2 population was nearly the same as that of the irradiated parents. At a radiation doses of 175 Gy the sterility of F 2 males was about 11% and of females 37%. At a dose of 200 Gy the levels of sterility of the males and females were 9 and 14%, respectively. Gamma irradiation did not affect the fecundity of the irradiated parents or of the F 1 and F 2 progeny. The average number of eggs produced by one pair of DBM moths was 180. The viabilities of unirradiated pupae, irradiated parents, F 1 and F 2 at a dose of 200 Gy were 94, 89, 54 and 65%, respectively. The effect of releasing F 1 sterile moths into untreated populations at a ratio of 45:1 could be a reduction in the population by 22%. Delta traps baited with the sex pheromone Sj showed the highest trapping efficiency. The highest population of DBMs in the dry season is in May and the lowest point is in July. The longevity of the tropical army worm was slightly affected by gamma irradiation. The dose of irradiation did not affect the viability of the pupae. A substerilizing dose of 100 Gy caused 43% parental sterility, 76% F 1 sterility and 54% F 2 sterility. (author). 7 refs, 3 figs, 8 tabs

  13. The effect of sterilization methods on the physical properties of silk sericin scaffolds.

    Science.gov (United States)

    Siritientong, Tippawan; Srichana, Teerapol; Aramwit, Pornanong

    2011-06-01

    Protein-based biomaterials respond differently to sterilization methods. Since protein is a complex structure, heat, or irradiation may result in the loss of its physical or biological properties. Recent investigations have shown that sericin, a degumming silk protein, can be successfully formed into a 3-D scaffolds after mixing with other polymers which can be applied in skin tissue engineering. The objective of this study was to investigate the effectiveness of ethanol, ethylene oxide (EtO) and gamma irradiation on the sterilization of sericin scaffolds. The influence of these sterilization methods on the physical properties such as pore size, scaffold dimensions, swelling and mechanical properties, as well as the amount of sericin released from sericin/polyvinyl alcohol/glycerin scaffolds, were also investigated. Ethanol treatment was ineffective for sericin scaffold sterilization whereas gamma irradiation was the most effective technique for scaffold sterilization. Moreover, ethanol also caused significant changes in pore size resulting from shrinkage of the scaffold. Gamma-irradiated samples exhibited the highest swelling property, but they also lost the greatest amount of weight after immersion for 24 h compared with scaffolds obtained from other sterilization methods. The results of the maximum stress test and Young's modulus showed that gamma-irradiated and ethanol-treated scaffolds are more flexible than the EtO-treated and untreated scaffolds. The amount of sericin released, which was related to its collagen promoting effect, was highest from the gamma-irradiated scaffold. The results of this study indicate that gamma irradiation should have the greatest potential for sterilizing sericin scaffolds for skin tissue engineering.

  14. Sterility Caused by Floral Organ Degeneration and Abiotic Stresses in Arabidopsis and Cereal Grains

    Directory of Open Access Journals (Sweden)

    Ashley Rae Smith

    2016-10-01

    Full Text Available Natural floral organ degeneration or abortion results in unisexual or fully sterile flowers, while abiotic stresses lead to sterility after initiation of floral reproductive organs. Since normal flower development is essential for plant sexual reproduction and crop yield, it is imperative to have a better understanding of plant sterility under regular and stress conditions. Here, we review the functions of ABC genes together with their downstream genes in floral organ degeneration and the formation of unisexual flowers in Arabidopsis and several agriculturally significant cereal grains. We further explore the roles of hormones, including auxin, brassinosteroids, jasmonic acid, gibberellic acid, and ethylene, in floral organ formation and fertility. We show that alterations in genes affecting hormone biosynthesis, hormone transport and perception cause loss of stamens/carpels, abnormal floral organ development, poor pollen production, which consequently result in unisexual flowers and male/female sterility. Moreover, abiotic stresses, such as heat, cold, and drought, commonly affect floral organ development and fertility. Sterility is induced by abiotic stresses mostly in male floral organ development, particularly during meiosis, tapetum development, anthesis, dehiscence, and fertilization. A variety of genes including those involved in heat shock, hormone signaling, cold tolerance, metabolisms of starch and sucrose, meiosis, and tapetum development are essential for plants to maintain normal fertility under abiotic stress conditions. Further elucidation of cellular, biochemical and molecular mechanisms about regulation of fertility will improve yield and quality for many agriculturally valuable crops.

  15. A tortoiseshell male cat

    DEFF Research Database (Denmark)

    Pedersen, A. S.; Berg, Lise Charlotte; Almstrup, Kristian

    2014-01-01

    Tortoiseshell coat color is normally restricted to female cats due to X-linkage of the gene that encodes the orange coat color. Tortoiseshell male cats do, however, occur at a low frequency among tortoiseshell cats because of chromosome aberrations similar to the Klinefelter syndrome in man...... tissue from a tortoiseshell male cat referred to us. Chromosome analysis using RBA-banding consistently revealed a 39,XXY karyotype. Histological examinations of testis biopsies from this cat showed degeneration of the tubules, hyperplasia of the interstitial tissue, and complete loss of germ cells....... Immunostaining using anti-vimentin and anti-VASA (DDX4) showed that only Sertoli cells and no germ cells were observed in the testicular tubules. As no sign of spermatogenesis was detected, we conclude that this is a classic case of a sterile, male tortoiseshell cat with a 39,XXY chromosome complement. © 2013 S...

  16. Radiation sterilization of animal farm sewage

    International Nuclear Information System (INIS)

    Rosiak, J.; Perkowski, J.; Pekala, W.

    1984-01-01

    Influence of irradiation on organisms appearing in farm sewage has been discussed. Practical examples of employing the radiation to sterilization of municipal wastes and liquid sewage from the industrial swine farms have been presented. (author)

  17. How to make a sterile helper.

    Science.gov (United States)

    Downing, Philip A; Cornwallis, Charlie K; Griffin, Ashleigh S

    2017-01-01

    The sterile worker castes found in the colonies of social insects are often cited as archetypal examples of altruism in nature. The challenge is to explain why losing the ability to mate has evolved as a superior strategy for transmitting genes into future generations. We propose that two conditions are necessary for the evolution of sterility: completely overlapping generations and monogamy. A review of the literature indicates that when these two conditions are met we consistently observe the evolution of sterile helpers. We explain the theory and evidence behind these ideas, and discuss the importance of ecology in predicting whether sterility will evolve using examples from social birds, mammals, and insects. In doing so, we offer an explanation for the extraordinary lifespans of some cooperative species which hint at ways in which we can unlock the secrets of long life. © 2016 WILEY Periodicals, Inc.

  18. Encapsulation process sterilizes and preserves surgical instruments

    Science.gov (United States)

    Montgomery, L. C.; Morelli, F. A.

    1964-01-01

    Ethylene oxide is blended with an organic polymer to form a sterile material for encapsulating surgical instruments. The material does not bond to metal and can be easily removed when the instruments are needed.

  19. Determination of sterilizing dose of lincocine drug

    International Nuclear Information System (INIS)

    Adawi, M.A.; Shamma, M.; Al-Mousa, A.

    1998-01-01

    There are too many antibiotics that have been studied on their dry solid state to determine their safe sterilizing dose by decreasing their bio burden in order to reach the sterility assurance level (SAL) needed. The sterilizing radiating dose of lincocine was determined according to information about their bio burden and radiating sensitivity at the sterility assurance level 10-6. The study of bio burden has shown that the contamination was fungal (Pemicillium sp.) and by applying the same tests to the raw materials of lincocine it came out that the cause of contamination was bad storage and that the radiating dose required to decrease the bio burden was 5.5 kGy. (author)

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

    Science.gov (United States)

    Mao, Jialin; Pfeifer, Samantha; Schlegel, Peter; Sedrakyan, Art

    2015-10-13

    To compare the safety and efficacy of hysteroscopic sterilization with the "Essure" device with laparoscopic sterilization in a large, all-inclusive, state cohort. Population based cohort study. Outpatient interventional setting in New York State. Women undergoing interval sterilization procedure, including hysteroscopic sterilization with Essure device and laparoscopic surgery, between 2005 and 2013. 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. 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%, Psterilization 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. 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 should be discussed with patients for informed decisions making. © Mao et al 2015.

  1. Cosmological and astrophysical implications of sterile neutrinos

    Science.gov (United States)

    Petraki, Kalliopi

    The discovery of neutrino masses suggests that the Standard Model should be supplemented with new gauge-singlet fermions, often called sterile neutrinos. The interplay among the new couplings introduced in the Standard Model can accommodate the neutrino oscillation data for a variety of choices: the new particles can be extremely heavy and practically unobservable, or they can be light, in which case they can solve several long-standing puzzles. It has been shown, for example, that sterile neutrinos in some range of masses can account for dark matter, their emission from a supernova can explain pulsar kicks, arid their decays can play an important role in the formation of the first stars. Though indirect, these clues indicate that sterile neutrinos can be the minimal solution to a variety of unsolved problems. This emphasizes the importance of investigating further the consequences of these new degrees of freedom for cosmology and astrophysics. In this dissertation, I explore the possible role of sterile neutrinos of different mass scales in some cosmological and astrophysical phenomena. A minimal extension of the Higgs sector of the Standard Model, with a gauge- singlet boson coupled to sterile neutrinos, can provide a consistent framework for the theory of neutrino masses, and can produce a relic population of keV sterile neutrinos via decays of the singlet Higgs. The latter can account for the dark matter of the universe. The mechanism operates around the electroweak scale, and has interesting consequences for the electroweak phase transition. Relic sterile neutrinos produced via decays at the electroweak scale constitute colder dark matter than those produced via other previously suggested mechanisms. The primordial thermal content of dark matter has important implications for the formation of cosmic structures, such as clusters and galaxies. The assessment of the relevant properties suggests that sterile neutrinos produced at the electroweak scale are a