Oviposition punctures in cucurbit fruits and their economic damage caused by the sterile female melon fly, Bactrocera cucurbitae Coquillett

International Nuclear Information System (INIS)

Miyatake, T.; Irabu, T.; Higa, R.

1993-01-01

Oviposition punctures caused by sterile females of the tephritid Bactrocera cucurbitae in cucurbit fruits were examined and economic damage was evaluated in Okinawa, Ryukyu Archipelago, Japan. Cage experiments in the field confirmed that sterile females make punctures (sterile stings) on fruits. The features of sterile stings differed depending on fruit species and were classified into 5 types

Female sterilization in India : The quality and effect of an observed sterilization camp at The Methodist Public Health Centre, Mursan, India

OpenAIRE

Wikborg, Pia; Svensk, Marie

2007-01-01

Population growth is a big challenge for India, and family planning is highly prioritized by the Government of India. Sterilization is the most common voluntary contraceptive method in India and has for many years been performed in camps. This thesis is based on our observation of a sterilization camp at the Methodist Public Health Centre in Mursan, India and available literature on the subject. We have looked closer at the effect of female sterilization as a method of contraception and t...

Geographic Variation in Characteristics of Postpartum Women Using Female Sterilization.

Science.gov (United States)

White, Kari; Potter, Joseph E; Zite, Nikki

2015-01-01

Southern states have higher rates of female sterilization compared with other areas of the United States, and the reasons for this are not well understood. We examined whether low-income and racial/ethnic minority women, who were previous targets of coercive practices, disproportionately report using sterilization in the South. We used data from 12 states participating in the Pregnancy Risk Assessment Monitoring System that collected information on women's contraceptive method use between 2006 and 2009. We categorized states according to geographic region: South, Midwest/West, and Northeast. Within each region, we computed the percentage of women using sterilization according to their demographic and obstetric characteristics and estimated multivariable-adjusted prevalence ratios to evaluate whether the same characteristics were associated with sterilization use. The percentage of postpartum women using sterilization ranged from 5.0% to 9.9% in the Northeast, 8.9% to 10.6% in the Midwest/West, and 11.6% to 22.4% in the South. Women in nearly all subgroups in Southern states were more likely to use sterilization than women in the Northeast. After multivariable adjustment, there were no differences in the prevalence of sterilization for Blacks compared with Whites in the Northeast (0.76; 95% CI, 0.55-1.06), Midwest/West (0.91; 95% CI, 0.80-1.04), and South (0.96; 95% CI, 0.85-1.07). Women with Medicaid-paid deliveries (vs. private insurance) had a higher prevalence of sterilization in all regions (p sterilization at disproportionately higher rates compared with other regions, and suggest that other differences, such as social norms and family planning policies, may contribute to this geographic variation. Copyright © 2015 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

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.

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.

Housefly population density correlates with shigellosis among children in Mirzapur, Bangladesh: a time series analysis.

Directory of Open Access Journals (Sweden)

Tamer H Farag

Full Text Available BACKGROUND: Shigella infections are a public health problem in developing and transitional countries because of high transmissibility, severity of clinical disease, widespread antibiotic resistance and lack of a licensed vaccine. Whereas Shigellae are known to be transmitted primarily by direct fecal-oral contact and less commonly by contaminated food and water, the role of the housefly Musca domestica as a mechanical vector of transmission is less appreciated. We sought to assess the contribution of houseflies to Shigella-associated moderate-to-severe diarrhea (MSD among children less than five years old in Mirzapur, Bangladesh, a site where shigellosis is hyperendemic, and to model the potential impact of a housefly control intervention. METHODS: Stool samples from 843 children presenting to Kumudini Hospital during 2009-2010 with new episodes of MSD (diarrhea accompanied by dehydration, dysentery or hospitalization were analyzed. Housefly density was measured twice weekly in six randomly selected sentinel households. Poisson time series regression was performed and autoregression-adjusted attributable fractions (AFs were calculated using the Bruzzi method, with standard errors via jackknife procedure. FINDINGS: Dramatic springtime peaks in housefly density in 2009 and 2010 were followed one to two months later by peaks of Shigella-associated MSD among toddlers and pre-school children. Poisson time series regression showed that housefly density was associated with Shigella cases at three lags (six weeks (Incidence Rate Ratio = 1.39 [95% CI: 1.23 to 1.58] for each log increase in fly count, an association that was not confounded by ambient air temperature. Autocorrelation-adjusted AF calculations showed that a housefly control intervention could have prevented approximately 37% of the Shigella cases over the study period. INTERPRETATION: Houseflies may play an important role in the seasonal transmission of Shigella in some developing

Desire for female sterilization among women wishing to limit births in rural Rakai, Uganda.

Science.gov (United States)

Lutalo, Tom; Gray, Ron; Mathur, Sanyukta; Wawer, Maria; Guwatudde, David; Santelli, John; Nalugoda, Fred; Makumbi, Fredrick

2015-11-01

Uganda has an unmet need for family planning of 34% and a total fertility rate of 6.2. We assessed the desire for female sterilization among sexually active women who wanted to stop childbearing in rural Rakai district, Uganda. 7192 sexually active women enrolled in a community cohort between 2002 and 2008 were asked about fertility intentions. Those stating that they did not want another child (limiters) were asked whether they would be willing to accept female sterilization, if available. Trends in desire for sterilization were determined by chi-square test for trend, and Modified Poisson regression was used to estimate prevalence rate ratios and 95% confidence intervals of the associations between desire for sterilization and socio-demographic characteristics and HIV status. From 2002 to 2008, the proportion of limiters dropped (from 47.2% to 43.7%; psterilization significantly increased from 54.2% to 63.1% (psterilization included higher number of living children (>=3), being HIV-infected and having received HIV counseling and testing. There is latent and growing desire for sterilization in this population. Our findings suggest a need to increase permanent contraception services for women who want to limit childbearing in this setting. A large unmet need for permanent female contraception services exists in Uganda. Efforts to increase the method mix by increasing permanent contraception services could reduce fertility rates and undesired births. Copyright © 2015 Elsevier Inc. All rights reserved.

Development of female medfly attractants to support the sterile insect technique: experiments conducted in Madeira, Portugal

International Nuclear Information System (INIS)

Pereira, R.

1999-01-01

With the availability of genetic sexing strains of Mediterranean fruit fly, Ceratitis capitata (Wied.), it is possible to release only sterile males in SIT programs. The availability of a new female medfly attractant can reduce labor costs because program progress can be monitored by trapping females instead of the usual male trapping with its labor intensive identification of sterile and wild males. Three Madeira studies evaluated new female attractants; ammonium acetate, putrescine and trimethylamine. One study was carried out in the same area during two different periods of 1996 (8 June to 27 July and 12 October to 30 November). A second study was conducted between 24 May to 05 July, 1997, in two different areas at the same altitude. One area had a wild fly population (sex ratio 1: 1) and the other was in an area where sterile males were released (sex ratio > 9: 1). The third study, conducted from 18 October to 29 November, 1997, compared wild fly captures at low elevations (80 m) with those at high elevations (700 m). The first study showed that the inclusion of the attractant trimethylamine significantly increased the wild female medfly. The percentage of medfly females in the traps with the two and the three attractants (FA-2 and FA-3) was more than 70%. In the second and third studies, the dry traps were more effective than wet traps in capturing wild medfly females. In areas with only wild females, the percentage of females captured was more than 62%. In areas where sterile males were released, the percentage of females captured was between 12% and 19%. In conclusion, the new attractants captured high percentages of females and, when combined with medfly genetic sexing strains, can reduce program costs significantly. (author)

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

Factors Related to Intention to Undergo Female Sterilization Among Married Women in Rural Kathmandu, Nepal.

Science.gov (United States)

Dhungana, Adhish; Nanthamongkolchai, Sutham; Pitikultang, Supachai

2016-03-01

Sterilization is most widely used fertility regulation method in Nepal. However, prevalence of uptake of female sterilization in central hilly region is less than the national average. The objective of the study was to explore the number and factors related to intention of married women to undergo female sterilization in rural Kathmandu which lies within central hilly region. This is a community based cross-sectional survey research conducted in rural area of Kathmandu valley. Two hundred and forty currently married women with at least one child of any age were interviewed using a structured pre-tested questionnaire. More than four-fifth of the respondents intended to undergo sterilization. Almost two-third of them wanted to limit their family size by taking this option. More than one-third of women not-intending to undergo sterilization feared weakness after sterilization. Age of the respondents, duration of marriage, and number of living children were significantly associated with intention to undergo sterilization. 15-24 years age group were six times more likely to have the intention for sterilization (OR 6.79, CI 2.28-20.19) compared to age 35 years and above group. Mothers with less than 3 living children are about three times more likely to have the intention to undergo sterilization (OR 2.87, CI 1.3-6.33) compared to women with more than 2 living children. Women married for 6 to 10 years were three times more likely to have the intention (OR 3.0, CI 1.09-8.27). However, gender of the living children was not associated with intention to undergo sterilization. There were significant numbers of women intending to undergo sterilization. Age of the mother, number of living children and the duration of marriage were found to be significantly influencing the intention to undergo sterilization. However, as intention refers to future plan, the respondents' intention may change over time. The national family planning program also needs to identify the key factors in

Variation of Musca domestica L. acetylcholinesterase in Danish housefly populations

DEFF Research Database (Denmark)

Kristensen, Michael; Huang, Jing; Qiao, Chuan-Ling

2006-01-01

Anti-cholinesterase resistance is in many cases caused by modified acetylcholinesterase (MACE). A comparison was made of toxicological data and AChE activity gathered from 21 field populations and nine laboratory strains of houseflies, Musca domestica L., to elucidate the best way of generating...... data to provide advice for management strategies and gathering information for resistance risk assessment on the organophosphates azamethiphos and dimethoate and the carbamate methomyl, which have been the primary insecticides used against adult houseflies in Denmark. Cluster analysis was performed...... and > 2000 houseflies were assigned to one of three phenotypes based on total acetylcholinesterase activity as well as inhibition by azamethiphos, methomyl or omethoate. A cluster, i.e. a phenotype, with high total AChE activity and high sensitivity to azamethiphos and less sensitivity to inhibition...

Hypertension and low birth weight babies in females sterilized with quinacrine in faisalabad from 1995 to 2005

International Nuclear Information System (INIS)

Afzal, S.; Mehboob, R.

2013-01-01

To find out hypertension and low birth weight babies in 6 to 17 years follow up after quinacrine sterilization (QS) during 1995-2005 in Faisalabad. Study design: The Cross sectional study. Place and duration of the study: The females who had transcervical insertion of quinacrine during 1995 to 2005 in Faisalabad were included in the survey. The duration of the survey was from January 2012 to April 2013. Subjects and Methods: The sample size calculated at 95% confidence level was 540. Sampling technique was simple random sampling. The home based survey of quinacrine sterilization was done by Lady health visitors and structured pretested questionnaires were filled. The examination and referral was done at the Manzar Medical Centre Faisalabad. Results: The frequency distribution and calculation of statistics showed the mean age at quinacrine sterilization was 38.5 years, standard deviation 6.517, standard error=0.461. The demographic features showed that the most of the females were living in rural areas (67%), poor (51.85%), unemployed (89.7%) and Iliterate (65%). In the study, low birth weight babies were in 9(1.66%) and hypertension was in 113 (20.9%) women after quinacrine sterilization. Conclusion: The hypertension and low birth weight babies were reported in females after quinacrine sterilization. Thus these findings may have a bearing on permanent sterilization practices and design of future investigations. (author)

A Z-linked sterility locus causes sexual abstinence in hybrid females and facilitates speciation in Spodoptera frugiperda.

Science.gov (United States)

Kost, Silvia; Heckel, David G; Yoshido, Atsuo; Marec, František; Groot, Astrid T

2016-06-01

In the fall armyworm, Spodoptera frugiperda (Lepidoptera, Noctuidae), two sympatric strains have been recognized that have been termed corn strain (C) and rice strain (R), referring to their most common host plants. Both strains are reproductively isolated via a distinct prezygotic barrier as well as via an intriguing postzygotic phenomenon: when R females have mated with C males, the resulting RC hybrid females exhibit dramatically reduced fertility independent of their mating partner. Here, we demonstrate that the reduced fertility is caused by the fact that these females refrain from mating, that is, females are behaviorally sterile. We identified a Z-chromosomally linked sterility locus that is most likely incompatible with yet to be identified autosomal (or cytoplasmic) factors, leading to the observed sexual abstinence. Within-chromosome mapping revealed the sterility locus to be located in an area of strongly reduced interstrain recombination. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

The Rise of Female Sterilization: A Closer Look at Colombia.

Science.gov (United States)

Folch, Beatriz M; Betstadt, Sarah; Li, Dongmei; Whaley, Natalie

2017-09-01

Objective In the 1970s, OCPs and IUDs were the most popular contraceptive methods in Colombia. According to data from the most recent Demographic and Health Survey (DHS), sterilization has become the most common form of birth control in Colombia. This study aims to examine the characteristics of Colombian women desiring long-acting contraception. Methods This study uses the 2005 and 2010 Colombian DHS dataset. Women who choose long-acting contraception were divided into those using female sterilization and those using long-acting reversible contraception (LARC). A multivariate logistic regression model was used to compare demographic and social determinants of contraceptive choice among reproductive age women seeking long-acting contraception between the years 2005 and 2010. Results Among women using a long-acting contraceptive method in 2010, compared to 2005, women were significantly more likely to be sterilized (1.14 OR, 95% CI 1.09-1.18) and less likely to use LARC (0.88 OR, 95% CI 0.85-0.92). Of women seeking long-acting contraception, those exposed to a family planning provider were less likely to undergo sterilization (0.54 OR, 95% CI 0.51-0.58) and more likely to use LARC (1.84 OR, 95% CI 1.73-1.96). When compared to all contraceptive users, younger women and women with less than two children were more likely to use LARC than sterilization. Conclusion Between 2005 and 2010, an increase in the proportion of contracepting women being sterilized in Colombia occurred. Our findings suggest that exposure to a family planning provider and appropriate contraceptive counseling appears to be key determinants of long-acting contraceptive choice. To improve use of long-acting, effective contraception, efforts should be made to increase access to family planning providers.

Provision of female sterilization in Ribeirão Preto, São Paulo, Brazil

Directory of Open Access Journals (Sweden)

Vieira Elisabeth Meloni

2004-01-01

Full Text Available Forty percent of Brazilian married women from 15 to 49 years of age have undergone surgical sterilization. The 1988 Brazilian Constitution states that all scientifically proven contraceptive methods should be available to all citizens, but it was only in 1997 that specific family planning legislation was approved. This study examines physicians' perceptions and attitudes towards the current provision of female sterilization and its legal implications, as well as women's experience with obtaining and undergoing sterilization. The study design included: (1 an investigation of the hospitals and health professionals and (2 a survey of women sterilized in combination with cesarean delivery in 1998. The survey showed they had a median of 3 living children, 60.0% had been sterilized between 30 and 39 years of age, and 61.0% had paid for the procedure. Many women reported previous method failure and adverse effects with hormonal contraceptives. Women with less schooling and lower socioeconomic status had more children and had begun childbearing and had been sterilized at younger ages than women with more schooling and higher socioeconomic status. Inequalities related to reproduction were strongly associated with teenage pregnancy and inadequate knowledge about contraceptives.

Provision of female sterilization in Ribeirão Preto, São Paulo, Brazil

Directory of Open Access Journals (Sweden)

Elisabeth Meloni Vieira

2004-10-01

Full Text Available Forty percent of Brazilian married women from 15 to 49 years of age have undergone surgical sterilization. The 1988 Brazilian Constitution states that all scientifically proven contraceptive methods should be available to all citizens, but it was only in 1997 that specific family planning legislation was approved. This study examines physicians' perceptions and attitudes towards the current provision of female sterilization and its legal implications, as well as women's experience with obtaining and undergoing sterilization. The study design included: (1 an investigation of the hospitals and health professionals and (2 a survey of women sterilized in combination with cesarean delivery in 1998. The survey showed they had a median of 3 living children, 60.0% had been sterilized between 30 and 39 years of age, and 61.0% had paid for the procedure. Many women reported previous method failure and adverse effects with hormonal contraceptives. Women with less schooling and lower socioeconomic status had more children and had begun childbearing and had been sterilized at younger ages than women with more schooling and higher socioeconomic status. Inequalities related to reproduction were strongly associated with teenage pregnancy and inadequate knowledge about contraceptives.

Infection rate of toxoplasma gondii and age distribution in female patients with sterility

International Nuclear Information System (INIS)

Li Shuhong; Dai Pei; Cui Liming; Zong Shan; Zuo Wenjing

2006-01-01

Objective: To discuss the relationship between the infection of Toxoplasma gondii and female sterility. Methods: Toxoplasma gondii serum antibody were determined in 882 women with sterility (experimental group) and 107 normal bearing women (control group) by using ELISA. At the same time the differences of the infection with Toxoplasma gondii between the ages of the sterility women were analyzed. Results: The positive rate in experimental group was 15.87% (140/882), the positive rate in control group was 5.61% (6/107), remarkable difference was found between two groups (P<0.01). The infection rate in the different age groups (20-24, 25-29, 30-34, 35-39 and ≥40) is 5.63%, 15.24%, 17.91%, 19.44% and 15.38%. Conclusion: Toxoplasma gondii infection may be one of the factors which can cause sterility, and the infection rates at different ages have no instinct differences. (authors)

Frequency of Resistance and Susceptible Bacteria Isolated from Houseflies

Directory of Open Access Journals (Sweden)

B Davari

2010-12-01

Conclusion: Houseflies collected from hospitals and slaughterhouse may be involved in the spread of drug resistant bacteria and may increase the potential of human exposure to drug resistant bacteria.

Sterilization of the melon fly, Dacus cucurbitae Coquillett (Diptera: Tephritidae), with gamma-radiation: Effect of dose on oviposition behavior of irradiated females

International Nuclear Information System (INIS)

Teruya, T.

1990-01-01

In a laboratory condition, the visiting and the puncturing frequencies of gamma-irradiated Dacus cucurbitae females on cucumber Cucumis sativus fruits were examined. In the non-irradiated females, the frequencies reached equilibrium ca. 1 week after adult emergence. The frequencies of the irradrated females decreased with irradiation dosage, but gradually resumed frequency with age. A similar trend was found in the relationship between the irradiation dose and the rates of the puncturing frequency to the visiting frequency. As the irradiation dose increased, the rate of under-developed ovaries increased. The ratio of cumulative puncturing frequency in the 70 Gy irradiated (completely sterile) females to that of the non-irradiated females was estimated as 1/200 when daily survival rate in the field was assumed to be 0.85. The completely sterile adult females (40 days old) made punctures on all sizes of cucumber cultivated in a greenhouse. However, these punctures do not significantly damage the fruit. The sting of the sterile melon fly would not be a serious problem in eradication programs based on the Sterile Insect Technique

Exuberant oral myiasis caused by Musca domestica (Housefly

Directory of Open Access Journals (Sweden)

Rajkumar N Parwani

2014-01-01

Full Text Available Tissues of oral cavity, when invaded by the parasitic larvae of houseflies, the condition is called as oral myiasis. It is a rare disease that is most common in developing countries and is associated with conditions leading to persistent mouth opening along with poor oral hygiene, suppurative lesions, severe halitosis and maxillofacial trauma. A case of exuberant oral myiasis in a 42-year-old female patient is described here. She reported with swelling, pain, mobility of teeth and foul odor. Diagnosis was based primarily on history and clinical features. Management included use of turpentine oil, mechanical removal of larvae followed by extraction of mobile teeth and curettage along with supportive antibiotic and analgesic therapy. Supportive nutritional supplements and timely institution of treatment encompassing removal of the offending larvae and carious teeth with proper education and motivation of the patient including oral hygiene instructions led to the resolution of these lesions.

Fatal attraction. Control of the housefly (Musca domestica)

NARCIS (Netherlands)

Smallegange, R.C.

2004-01-01

Despite its long association with man, the housefly (Musea domestica Linnaeus) remains one of the most difficult pests to control. It is a ubiquitous insect that can be found in houses, stables, food processing factories and other domesticated areas and buildings. Reliance on insecticides for fly

Genome-Wide Analysis of DNA Methylation During Ovule Development of Female-Sterile Rice fsv1

Directory of Open Access Journals (Sweden)

Helian Liu

2017-11-01

Full Text Available The regulation of female fertility is an important field of rice sexual reproduction research. DNA methylation is an essential epigenetic modification that dynamically regulates gene expression during development processes. However, few reports have described the methylation profiles of female-sterile rice during ovule development. In this study, ovules were continuously acquired from the beginning of megaspore mother cell meiosis until the mature female gametophyte formation period, and global DNA methylation patterns were compared in the ovules of a high-frequency female-sterile line (fsv1 and a wild-type rice line (Gui99 using whole-genome bisulfite sequencing (WGBS. Profiling of the global DNA methylation revealed hypo-methylation, and 3471 significantly differentially methylated regions (DMRs were observed in fsv1 ovules compared with Gui99. Based on functional annotation and Kyoto encyclopedia of genes and genomes (KEGG pathway analysis of differentially methylated genes (DMGs, we observed more DMGs enriched in cellular component, reproduction regulation, metabolic pathway, and other pathways. In particular, many ovule development genes and plant hormone-related genes showed significantly different methylation patterns in the two rice lines, and these differences may provide important clues for revealing the mechanism of female gametophyte abortion.

Enterobacteria associated with houseflies (Musca domestica) as an infection risk indicator in swine production farms.

Science.gov (United States)

Cervelin, V; Fongaro, G; Pastore, J B; Engel, F; Reimers, M A; Viancelli, A

2018-04-23

Houseflies (Musca domestica) spend part of their life development on animal or human manure. Manure is high in pathogenic microbes; thus, houseflies have been known as a mechanical vector for various important zoonotic diseases. Therefore, the present study showcases captured houseflies from intensive swine production regions (which are areas of high manure concentration) in Southern Brazil, and analyses their bodies' to the presence of Escherichia coli and Salmonella sp. and the sensitivity of these bacteria to various antibiotics. Additionally, Quantitative Microbiology Risk Assessment was performed simulating the contamination of lettuce by flies' bacteria and subsequent lettuce consumption by an adult human being. Houseflies were captured in swine buildings and farm houses from five farms. E. coli quantification values ranged from 10 4 to 10 6 CFU/20 flies, and all sampling sites had positive results from bacteria presence in the collected houseflies. On the other hand, Salmonella sp. presence was observed in only three farms, where the quantification ranged from 10 2 to 10 5 CFU/20 flies. The bacteria showed to be resistant to at least two from the four tested antibiotics (ampicillin, Cefalotin, Ciprofloxacin and Norfloxacin) antibiotics used in human or veterinary medicine. Infection probability analyses showed risk of human infection by E.coli, indicating possible transmission of zoonotic pathogens through flies. In this context, it was possible to conclude that there is a need for flies control, especially in swine farms where zoonotic pathogens can be abundant, to minimize the health impact of the vectorization of enteric bacteria. Copyright © 2018 Elsevier B.V. All rights reserved.

Pheromones of the housefly : A chemical and behavioural study

NARCIS (Netherlands)

Noorman, N

2001-01-01

Houseflies (Musca domestica L.) often make themselves a nuisance in human and livestock habitations. Moreover, these flies may transmit over a hundred different pathogens. They can transmit intestinal worms or their eggs, and are potential vectors of pathogens of, for example, dysentery,

Attitude toward, acceptance of and knowledge about female sterilization as a method of contraception.

Science.gov (United States)

Erlenwein, J; Kundu, S; Schippert, C; Soergel, P; Hillemanns, P; Staboulidou, I

2015-02-01

Surgical sterilization via tubal ligation or the disconnection of the tubes is a method of permanent contraception. The aim of this study was to evaluate the attitude, acceptance and knowledge of women about female sterilization as a method of contraception in terms of the social and cultural backgrounds of those women. Prospective study based on an anonymous questionnaire that analyzed background knowledge, attitude, influence factors and motivation regarding sterilization, as well as the reasons for declining. The questionnaire also attempted to evaluate the effects on the self-esteem of the women, as well as the impact of religious dogma and the related beliefs. One thousand, eight hundred questionnaires were distributed, and 1247 women completed the questionnaire—a response rate of 69.3%. There were mainly positive attitudes toward sterilization as a contraceptive method. Cultural background, including religion and faith; the mother's experiences and point of view; knowledge; family planning and the actual life situation have an influence on the attitudes toward and acceptance of sterilization as a contraceptive method and on the final choice of a contraceptive method. Cultural background and present life situation have a great impact on the attitude toward and acceptance of sterilization as a method of contraception, thus influencing the final choice of a contraceptive method. Detailed counselling about this topic is essential and should be improved. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Mediterranean fruit fly: interference of oviposition by radiation-sterilized females in field cages

Energy Technology Data Exchange (ETDEWEB)

McInnis, D. O. [Tropical Fruit and Vegetable Research Lab. USDA-ARS, Honolulu, HI (United States); Wong, T. T.Y.

1990-07-01

In experiments between April and September 1984, the behaviour of nonirradiated and radiation-sterilized laboratory-adapted adults of the tephritid Ceratitis capitata was observed on apples hung on guava trees in outdoor cages in Hawaii. The numbers of nonirradiated females observed resting on fruit were reduced several times by the presence of irradiated females, either alone or with irradiated males, but not by irradiated males alone. Similarly, the number of nonirradiated females observed ovipositing and the duration of oviposition was reduced by the presence of irradiated females. In control cages (all nonirradiated flies), the duration of oviposition by females averaged 255.9±15.0 s on fruit, while most of nonirradiated and irradiated females in the mixed (treatment) cage averaged 157±19.8 s and 77.5±7.5 s on fruit, resp. Irradiated females behaved skittishly on fruit and frequently engaged in physical encounters with other flies.

Laparoscopic female sterilization.

Science.gov (United States)

Filshie, G M

1989-09-01

An overview of laparoscopic sterilization techniques from a historical and practical viewpoint includes instrumentation, operative techniques, mechanical occlusive devices, anesthesia, failure rates, morbidity and mortality. Laparoscope was first reported in 1893, but was developed simultaneously in France, Great Britain, Canada and the US in the 1960s. There are smaller laparoscopes for double-puncture procedures, and larger, single-puncture laparoscopes. To use a ring or clip, a much larger operating channel, up to 8 mm is needed. Insufflating gas may be CO2, which does not support combustion, but is more uncomfortable, NO2, which is also an anesthetic, and room air often used in developing countries. Unipolar electrocautery is now rarely used, in fact most third party payers do not allow it. Bipolar cautery, thermal coagulation and laser photocoagulation are safer methods. Falope rings, Hulka-Clemens, Filshie, Bleier, Weck and Tupla clips are described and illustrated. General anesthesia, usually a short acting agent with a muscle relaxant, causes 33% of the mortality of laparoscope, often due to cardiac arrest and arrhythmias, preventable with atropine. Local anesthesia is safer and cheaper and often used in developing countries. Failure rates of the various laparoscopic tubal sterilization methods are reviewed: most result from fistula formation. Mortality and morbidity can be caused by bowel damage, injury or infection, pre- existing pelvic infection, hemorrhage, gas embolism (avoidable by the saline drip test), and other rare events.

Inherited sterility in insects

International Nuclear Information System (INIS)

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

2005-01-01

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

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

International Nuclear Information System (INIS)

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

1976-01-01

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

Genetic Analysis of Three Dominant Female-Sterile Mutations Located on the X Chromosome of DROSOPHILA MELANOGASTER

OpenAIRE

Busson, D.; Gans, M.; Komitopoulou, K.; Masson, M.

1983-01-01

Three dominant female-sterile mutations were isolated following ethyl methanesulfonate (EMS) mutagenesis. Females heterozygous for two of these mutations show atrophy of the ovaries and produce no eggs (ovo D1) or few eggs (ovoD2); females heterozygous for the third mutation, ovoD3, lay flaccid eggs. All three mutations are germ line-dependent and map to the cytological region 4D-E on the X chromosome; they represent a single allelic series. Two doses of the wild-type allele restore fertility...

Inheritance of sterility in Dysdercus koenigii F. (Hemiptera: Pyrrhocoridae)

International Nuclear Information System (INIS)

Harwalkar, M.R.; Rahalkar, G.W.

1979-01-01

It has been suggested that for the control of Lepidopterous populations, release of fully competitive partially sterile males would be more advantageous than the release of completely sterile males. This suggestion is based on the fact, elucidated in many studies, that partially sterilized males mated to normal females produce totally sterile or partially sterile progeny. In Hemiptera too, F 1 progeny of partially sterile males has been shown to inherit sterility. Individual impact of sterility inherited by either sex of the F 1 progeny on population growth has been studied in an hemipteran insect Dysdercus koenigii. A dose of 7 krad induces near-complete sterility in males. When males irradiated with substerilizing doses of 1,2 and 3 krad were crossed with normal females, F 1 progeny of both sexes was partially sterile : the female being more sterile than the males. When the F 1 progeny was intercrossed, there was enhanced reduction in progeny production. (auth.)

Fungal dissemination by housefly (Musca domestica L.) and contamination of food commodities in rural areas of South Africa.

Science.gov (United States)

Phoku, J Z; Barnard, T G; Potgieter, N; Dutton, M F

2016-01-18

Several insects that act as vectors, including houseflies (Musca domestica L.), are often considered to be an important source of fungal contamination in human foods. Houseflies are also involved in the transmission of bacterial pathogens that may pose a serious hazard to human health. Thus, the rural population of South Africa, as typified by that in the Gauteng Province investigated in this study, is at high risk from fungal exposure disseminated by houseflies and it is therefore important to assess the role of flies in contaminating various food commodities. Eighty four samples of houseflies (captured from households and pit toilets) were studied for their potential to carry fungal spores into food commodities. The fungi occurring in samples of raw maize (15) and porridge (19) were also assessed. Fungal isolates were identified based on morphological characteristics by conventional identification methods. Fifteen genera of fungi were isolated and identified, of which Aspergillus, Fusarium, Penicillium, Cladosporium, Moniliella and Mucor were the most prevalent in all three sample types analysed. The incidence rates of fungal contamination per total fungal count isolated in houseflies, maize and porridge were recorded with mean fungal load of 2×10(8) CFU/ml, 1×10(7)CFU/g and 2×10(7)CFU/g respectively. Additionally, A. flavus, A. parasiticus, F. verticillioides, F. proliferatum, P. verrucosum, P. aurantiogriseum and M. suaveolens were the most frequent fungal isolates in houseflies with incidence rate of 34%, 11%, 27%, 21%, 22%, 17% and 32% respectively. F. verticillioides, A. flavus, A. niger and P. oslonii were the most prevalent species contaminating porridge and maize with incidence rate of 23%, 32%, 16% and 28% in maize samples, while incidence rates of 59%, 15% and 29% were recorded in porridge samples with the exception of F. verticillioides. The prevalence of these genera of fungi may pose serious health risks. Copyright © 2015 Elsevier B.V. All rights

Genetic basis of the sterile insect technique

International Nuclear Information System (INIS)

Robinson, A.S.

2014-01-01

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

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

International Nuclear Information System (INIS)

Kiyoku, Masao; Tsukuda, Ritsuko

1974-01-01

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

Linkage of male determining factor(M) in a Danish housefly strain

DEFF Research Database (Denmark)

Højland, Dorte Heidi; Kristensen, Michael; Scott, Jeffrey G

Spinosad has been introduced for housefly control within the last decade and plays an essential role in pest management strategies of multiple insect pests. However, spinosad resistance is emerging in various pest species, questioning the further use of spinosad in pest management. Prior to use a...

Distribution and substrate specificity of esterases in the housefly, Musca domestica L.

NARCIS (Netherlands)

Asperen, K. van

1959-01-01

Housefly homogenates perform high cholinesterase and ali-esterase activity. Warburg-manometric studies show that acetylcholine, acetyl-β-methylcholine, butyrylcholine, and benzoylcholine are exclusively hydrolysed by a cholinesterase, the properties of which are more or less comparable to those of

Quinacrine non-surgical female sterilization in Bangladesh.

Science.gov (United States)

Bhuiyan, S N; Begum, R

2001-11-01

This study was undertaken to evaluate the efficacy, safety, and acceptability of transcervical applications of quinacrine along with other adjuvants, such as ampicillin and ibuprofen, for sterilization. The cohort consisted of 750 normal women who requested sterilization and volunteered for this method at the family planning clinic of a tertiary hospital and community clinics in Chittagong, Bangladesh. Several different protocols were followed from October 1989 to April 1999. Each woman received one or two insertions of 180 mg or 252 mg quinacrine with or without adjuvants including 55.5 mg ibuprofen or 125 mg ampicillin. Supplementary contraception was given in the form of combined oral contraceptive pills, barrier methods, or injection of depot medroxyprogesterone acetate for 3 months. Details of each protocol are described in the text. The gross pregnancy failure rate for insertion of 180 mg in 590 women was 3.9% compared to 1.9% for the 160 who received 252 mg. There were no serious complications, and side effects were transient. We conclude that quinacrine non-surgical sterilization is a safe, acceptably effective method when two insertions of 252 mg quinacrine with medroxyprogesterone injection as a supplement is used.

Combining the Sterile Insect Technique with Wolbachia-Based Approaches: II--A Safer Approach to Aedes albopictus Population Suppression Programmes, Designed to Minimize the Consequences of Inadvertent Female Release.

Directory of Open Access Journals (Sweden)

Dongjing Zhang

Full Text Available Due to the absence of a perfect method for mosquito sex separation, the combination of the sterile insect technique and the incompatible insect technique is now being considered as a potentially effective method to control Aedes albopictus. In this present study first we examine the minimum pupal irradiation dose required to induce complete sterility in Wolbachia triple-infected (HC, double-infected (GUA and uninfected (GT female Ae. albopictus. The HC line is a candidate for Ae. albopictus population suppression programmes, but due to the risk of population replacement which characterizes this triple infected line, the individuals to be released need to be additionally irradiated. After determining the minimum irradiation dose required for complete female sterility, we test whether sterilization is sufficient to prevent invasion of the triple infection from the HC females into double-infected (GUA populations. Our results indicate that irradiated Ae. albopictus HC, GUA and GT strain females have decreased fecundity and egg hatch rate when irradiated, inversely proportional to the dose, and the complete sterilization of females can be acquired by pupal irradiation with doses above 28 Gy. PCR-based analysis of F1 and F2 progeny indicate that the irradiated HC females, cannot spread the new Wolbachia wPip strain into a small cage GUA population, released at a 1:5 ratio. Considering the above results, we conclude that irradiation can be used to reduce the risk of population replacement caused by an unintentional release of Wolbachia triple-infected Ae. albopictus HC strain females during male release for population suppression.

Influence of spermatogenesis functional state on female sterility under single local x-irradiation

International Nuclear Information System (INIS)

Strel'nikova, N.K.; Kudritskaya, O.Yu.

1978-01-01

An experiment which simulated conditions of radiation exposure in X ray studies of human beings was staged to see what was the contribution of the sex-related radiosensitivity to the biologic effect from local exposure of the pelvis region. Second-generation white mice were irradiated with doses of 7.34 to 360 R. It was found that with the dose increase, the number of sterile females also increased with a concomitant reduction in the number of live spermatozoa in the seman of males, which can be considered as evidence that these two processes are interrelated

The Effects of Oral Application of Cyromazine and Triflumuron on House-Fly Larvae

Directory of Open Access Journals (Sweden)

B Vazirianzadeh

2007-12-01

Full Text Available Accumulations of large quantities of wastes (manure, used litter, dead birds which are excellent medium for fly-larvae over poultry houses provide breeding places for different groups of fly pests, with house-flies being the dominant species. This project is a comparative lab study. In this research project the larvicidal effects of cyromazine and triflumuron were studied as two Insect Growth Regulators (IGRs to reduce the fly population using oral application. Both IGRs had a signifi-cant effect on larval mortality compared with their controls among the concentrations (P< 0.01, Fisher's LSD with Bonf-feroni correction including a dose-dependent relationship. Comparisons among LC50 and LC90 values, using fiducial limits, showed that cyromazine was significantly more toxic to the larvae of the two strains than triflumuron. It is concluded that cyromazine should be used in a larvicidal programme to control house-fly rather than triflumuron.

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

Interaction of some organophosphorus compounds in susceptible and resistant houseflies (Musca domestica L.)

NARCIS (Netherlands)

Abdallah, M.D.

1963-01-01

The effect of tri-ortho-cresylphosphate (TOCP) on poisoning by parathion and paraoxon in susceptible and resistant houseflies (Musca domestica L.) was investigated.

TOCP influenced the penetration of parathion and paraoxon, and this could explain the contradictory results of both an

Mastitis in dairy cattle caused by Corynebacterium pseudotuberculosis and the feasibility of transmission by houseflies. I.

Science.gov (United States)

Yeruham, I; Braverman, Y; Shpigel, N Y; Chizov-Ginzburg, A; Saran, A; Winkler, M

1996-09-01

Morbidity due to Corynebacterium pseudotuberculosis infection occurred in 29 dairy herds. The disease appeared basically in three clinical forms: cutaneous, mastitic, and visceral. The appearance of the disease showed a marked seasonality: in 23 herds it occurred during the spring and summer months (dry season) (March-October). The mastitic form occurred in only 10 herds and the causative bacterium was isolated from 33 cows (5.8%). All the strains of C. pseudotuberculosis isolated from the milk samples were found not to be nitrate reducers. The bacterium was excreted in the milk of six cows from herd B during a period of 11 months. In the mastitic cows, a decrease in milk production and considerable increases in the somatic cell count were noted. C. pseudotuberculosis was isolated from houseflies collected over a cow lesion. Laboratory-reared houseflies were successfully infected with C. pseudotuberculosis-contaminated milk, broth and sugar cubes. Flies infected with the bacterium from contaminated milk excreted the bacterium in their droppings for up to 4 h and from their saliva for up to 3 h post infection. The bacterium survived on the external organs of houseflies for no longer than 10 min post infection, after the flies had been dipped in contaminated broth.

The Effects of Oral Application of Cyromazine and Triflumuron on House-Fly Larvae

Directory of Open Access Journals (Sweden)

B Vazirianzadeh

2007-11-01

Full Text Available Accumulations of large quantities of wastes (manure, used litter, dead birds which are excellent medium for fly-larvae over poultry houses provide breeding places for different groups of fly pests, with house-flies being the dominant species. This project is a comparative lab study. In this research project the larvicidal effects of cyromazine and triflumuron were studied as two Insect Growth Regulators (IGRs to reduce the fly population using oral application. Both IGRs had a signifi-cant effect on larval mortality compared with their controls among the concentrations (P< 0.01, Fisher's LSD with Bonf-feroni correction including a dose-dependent relationship. Comparisons among LC50 and LC90 values, using fiducial limits, showed that cyromazine was significantly more toxic to the larvae of the two strains than triflumuron. It is concluded that cyromazine should be used in a larvicidal programme to control house-fly rather than triflumuron.

Transcriptome Analysis of an Insecticide Resistant Housefly Strain: Insights about SNPs and Regulatory Elements in Cytochrome P450 Genes.

Science.gov (United States)

Mahmood, Khalid; Højland, Dorte H; Asp, Torben; Kristensen, Michael

2016-01-01

Insecticide resistance in the housefly, Musca domestica, has been investigated for more than 60 years. It will enter a new era after the recent publication of the housefly genome and the development of multiple next generation sequencing technologies. The genetic background of the xenobiotic response can now be investigated in greater detail. Here, we investigate the 454-pyrosequencing transcriptome of the spinosad-resistant 791spin strain in relation to the housefly genome with focus on P450 genes. The de novo assembly of clean reads gave 35,834 contigs consisting of 21,780 sequences of the spinosad resistant strain. The 3,648 sequences were annotated with an enzyme code EC number and were mapped to 124 KEGG pathways with metabolic processes as most highly represented pathway. One hundred and twenty contigs were annotated as P450s covering 44 different P450 genes of housefly. Eight differentially expressed P450s genes were identified and investigated for SNPs, CpG islands and common regulatory motifs in promoter and coding regions. Functional annotation clustering of metabolic related genes and motif analysis of P450s revealed their association with epigenetic, transcription and gene expression related functions. The sequence variation analysis resulted in 12 SNPs and eight of them found in cyp6d1. There is variation in location, size and frequency of CpG islands and specific motifs were also identified in these P450s. Moreover, identified motifs were associated to GO terms and transcription factors using bioinformatic tools. Transcriptome data of a spinosad resistant strain provide together with genome data fundamental support for future research to understand evolution of resistance in houseflies. Here, we report for the first time the SNPs, CpG islands and common regulatory motifs in differentially expressed P450s. Taken together our findings will serve as a stepping stone to advance understanding of the mechanism and role of P450s in xenobiotic detoxification.

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

Development of female medfly attractant systems for trapping and sterility assessment. Proceedings of a final research co-ordination meeting

International Nuclear Information System (INIS)

1999-07-01

Practical application of the sterile insect technique (SIT) against major insect pests will continue to increase as the repeated use of insecticides is recognized as an environmental problem. In the case of the Mediterranean fruit fly (medfly), which attacks over 300 species of fruits and vegetables in tropical, subtropical, and temperate climates on all five continents, control is still largely based on frequent insecticide spraying, often more than 10 sprays per fruiting season. Methods for population estimation, which accurately reflect changes due to movement, mortality or reproduction, are a prerequisite for effective pest management and in particular for use of SIT. With better monitoring tools medfly populations can be estimated more accurately and compared under different conditions, to guide decisions on alternative (i.e. more effective and more environment-friendly) control strategies. In support of this need in the application of SIT field programmes against medfly, an FAO/IAEA co-ordinated research project (CRP) was carried out which resulted in a TECDOC published in 1996 on Standardization of Medfly Trapping for Use in sterile insect technique Programmes. Following the development of male only genetic sexing strains at the FAO/IAEA Agriculture and Biotechnology Laboratories in Seibersdorf, Austria, it was recognized that the development of a female medfly targeted trapping system, in conjunction with only male sterile releases, would improve the efficacy of the SIT, reduce costs, and more effectively utilize sterile males. As a result, a new FAO/IAEA Co-ordinated Research Project on Development of Female Medfly Attractant Systems for Trapping and Sterility Assessment was initiated in 1994 with the objective to develop new synthetic female medfly attractants and to determine their efficacy compared to proteinaceous baits under different weather, host-tree and population density conditions. Findings obtained during the course of this 5-year CRP are

Development of female medfly attractant systems for trapping and sterility assessment. Proceedings of a final research co-ordination meeting

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-07-01

Practical application of the sterile insect technique (SIT) against major insect pests will continue to increase as the repeated use of insecticides is recognized as an environmental problem. In the case of the Mediterranean fruit fly (medfly), which attacks over 300 species of fruits and vegetables in tropical, subtropical, and temperate climates on all five continents, control is still largely based on frequent insecticide spraying, often more than 10 sprays per fruiting season. Methods for population estimation, which accurately reflect changes due to movement, mortality or reproduction, are a prerequisite for effective pest management and in particular for use of SIT. With better monitoring tools medfly populations can be estimated more accurately and compared under different conditions, to guide decisions on alternative (i.e. more effective and more environment-friendly) control strategies. In support of this need in the application of SIT field programmes against medfly, an FAO/IAEA co-ordinated research project (CRP) was carried out which resulted in a TECDOC published in 1996 on Standardization of Medfly Trapping for Use in sterile insect technique Programmes. Following the development of male only genetic sexing strains at the FAO/IAEA Agriculture and Biotechnology Laboratories in Seibersdorf, Austria, it was recognized that the development of a female medfly targeted trapping system, in conjunction with only male sterile releases, would improve the efficacy of the SIT, reduce costs, and more effectively utilize sterile males. As a result, a new FAO/IAEA Co-ordinated Research Project on Development of Female Medfly Attractant Systems for Trapping and Sterility Assessment was initiated in 1994 with the objective to develop new synthetic female medfly attractants and to determine their efficacy compared to proteinaceous baits under different weather, host-tree and population density conditions. Findings obtained during the course of this 5-year CRP are

Multilevel Perspectives on Female Sterilization in Low-Income Communities in Mumbai, India.

Science.gov (United States)

Brault, Marie A; Schensul, Stephen L; Singh, Rajendra; Verma, Ravi K; Jadhav, Kalpita

2016-09-01

Surgical sterilization is the primary method of contraception among low-income women in India. This article, using qualitative analysis of key informant, in-depth interviews, and quantitative analyses, examines the antecedents, process, and outcomes of sterilization for women in a low-income area in Mumbai, India. Family planning policies, socioeconomic factors, and gender roles constrain women's reproductive choices. Procedures for sterilization rarely follow protocol, particularly during pre-procedure counseling and consent. Women who choose sterilization often marry early, begin conceiving soon after marriage, and reach or exceed ideal family size early due to problems in accessing reversible contraceptives. Despite these constraints, this study indicates that from the perspective of women, the decision to undergo sterilization is empowering, as they have fulfilled their reproductive duties and can effectively exercise control over their fertility and sexuality. This empowerment results in little post-sterilization regret, improved emotional health, and improved sexual relationships following sterilization. © The Author(s) 2015.

A sterile-female technique proposed for control of Striga hermonthica and other intractable weeds: Advantages, shortcomings, and risk management

Science.gov (United States)

Weeds have posed intractable challenges to farmers since the dawn of agriculture. This article describes in detail a proposed control strategy based on the introduction of genes conferring female-sterility into the genomes of intractable target weeds. Spread of these genes through target populations...

Genetic complexity underlying hybrid male sterility in Drosophila.

Science.gov (United States)

Sawamura, Kyoichi; Roote, John; Wu, Chung-I; Yamamoto, Masa-Toshi

2004-02-01

Recent genetic analyses of closely related species of Drosophila have indicated that hybrid male sterility is the consequence of highly complex synergistic effects among multiple genes, both conspecific and heterospecific. On the contrary, much evidence suggests the presence of major genes causing hybrid female sterility and inviability in the less-related species, D. melanogaster and D. simulans. Does this contrast reflect the genetic distance between species? Or, generally, is the genetic basis of hybrid male sterility more complex than that of hybrid female sterility and inviability? To clarify this point, the D. simulans introgression of the cytological region 34D-36A to the D. melanogaster genome, which causes recessive male sterility, was dissected by recombination, deficiency, and complementation mapping. The 450-kb region between two genes, Suppressor of Hairless and snail, exhibited a strong effect on the sterility. Males are (semi-)sterile if this region of the introgression is made homozygous or hemizygous. But no genes in the region singly cause the sterility; this region has at least two genes, which in combination result in male sterility. Further, the males are less fertile when heterozygous with a larger introgression, which suggests that dominant modifiers enhance the effects of recessive genes of male sterility. Such an epistatic view, even in the less-related species, suggests that the genetic complexity is special to hybrid male sterility.

Chromosome Synapsis and Recombination in Male-Sterile and Female-Fertile Interspecies Hybrids of the Dwarf Hamsters (Phodopus, Cricetidae

Directory of Open Access Journals (Sweden)

Tatiana I. Bikchurina

2018-04-01

Full Text Available Hybrid sterility is an important step in the speciation process. Hybrids between dwarf hamsters Phodopus sungorus and P. campbelli provide a good model for studies in cytological and genetic mechanisms of hybrid sterility. Previous studies in hybrids detected multiple abnormalities of spermatogenesis and a high frequency of dissociation between the X and Y chromosomes at the meiotic prophase. In this study, we found that the autosomes of the hybrid males and females underwent paring and recombination as normally as their parental forms did. The male hybrids showed a significantly higher frequency of asynapsis and recombination failure between the heterochromatic arms of the X and Y chromosomes than the males of the parental species. Female hybrids as well as the females of the parental species demonstrated a high incidence of centromere misalignment at the XX bivalent and partial asynapsis of the ends of its heterochromatic arms. In all three karyotypes, recombination was completely suppressed in the heterochromatic arm of the X chromosome, where the pseudoautosomal region is located. We propose that this recombination pattern speeds up divergence of the X- and Y-linked pseudoautosomal regions between the parental species and results in their incompatibility in the male hybrids.

Background odour induces adaptation and sensitization of olfactory receptors in the antennae of houseflies

NARCIS (Netherlands)

Kelling, F.J; Ialenti, F.; den Otter, C.J

The presence of background odour was found to have a small but significant effect on the sensitivity of the antennal olfactory system of houseflies, Musca domestica Linnaeus (Diptera: Muscidae), to new pulses of odour. We show that cross-adaptation and cross-sensitization between a background odour

Differential distribution of glutamate- and GABA-gated chloride channels in the housefly Musca domestica.

Science.gov (United States)

Kita, Tomo; Ozoe, Fumiyo; Azuma, Masaaki; Ozoe, Yoshihisa

2013-09-01

l-Glutamic acid (glutamate) mediates fast inhibitory neurotransmission by affecting glutamate-gated chloride channels (GluCls) in invertebrates. The molecular function and pharmacological properties of GluCls have been well studied, but not much is known about their physiological role and localization in the insect body. The distribution of GluCls in the housefly (Musca domestica L.) was thus compared with the distribution of γ-aminobutyric acid (GABA)-gated chloride channels (GABACls). Quantitative PCR and ligand-binding experiments indicate that the GluCl and GABACl transcripts and proteins are predominantly expressed in the adult head. Intense GluCl immunostaining was detected in the lamina, leg motor neurons, and legs of adult houseflies. The GABACl (Rdl) immunostaining was more widely distributed, and was found in the medulla, lobula, lobula plate, mushroom body, antennal lobe, and ellipsoid body. The present findings suggest that GluCls have physiological roles in different tissues than GABACls. Copyright © 2013 Elsevier Ltd. All rights reserved.

Segregation of male-sterility alleles across a species boundary.

Science.gov (United States)

Weller, S G; Sakai, A K; Culley, T M; Duong, L; Danielson, R E

2014-02-01

Hybrid zones may serve as bridges permitting gene flow between species, including alleles influencing the evolution of breeding systems. Using greenhouse crosses, we assessed the likelihood that a hybrid zone could serve as a conduit for transfer of nuclear male-sterility alleles between a gynodioecious species and a hermaphroditic species with very rare females in some populations. Segregation patterns in progeny of crosses between rare females of hermaphroditic Schiedea menziesii and hermaphroditic plants of gynodioecious Schiedea salicaria heterozygous at the male-sterility locus, and between female S. salicaria and hermaphroditic plants from the hybrid zone, were used to determine whether male-sterility was controlled at the same locus in the parental species and the hybrid zone. Segregations of females and hermaphrodites in approximately equal ratios from many of the crosses indicate that the same nuclear male-sterility allele occurs in the parent species and the hybrid zone. These rare male-sterility alleles in S. menziesii may result from gene flow from S. salicaria through the hybrid zone, presumably facilitated by wind pollination in S. salicaria. Alternatively, rare male-sterility alleles might result from a reversal from gynodioecy to hermaphroditism in S. menziesii, or possibly de novo evolution of male sterility. Phylogenetic analysis indicates that some species of Schiedea have probably evolved separate sexes independently, but not in the lineage containing S. salicaria and S. menziesii. High levels of selfing and expression of strong inbreeding depression in S. menziesii, which together should favour females in populations, argue against a reversal from gynodioecy to hermaphroditism in S. menziesii. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Inherited sterility in cabbage pest crocidolomia binotalis zell as induced by gamma rays

International Nuclear Information System (INIS)

Sutrisno, S.

1983-01-01

Male moths of crocidolomia binotalis which have been irradiated with gamma rays at a dose of 0.325 kGy were mated with the untreated females. The resulted sterility observed from this mating was 70.86%. A higher sterility was obtained from either male or female F1 offspring when mated with untreated insects (88.62% and 89.46%, respectively). Irradiation of female moths at a dose of 0.15 kGy resulted in 79.6% sterility, however, the sterility of their first offsprings was lower. (author)

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.)

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)

Evaluation of Beauveria bassiana infection in the hemolymph serum proteins of the housefly, Musca domestica L. (Diptera: Muscidae).

Science.gov (United States)

Mishra, Sapna; Kumar, Peeyush; Malik, Anushree

2017-11-01

Beauveria bassiana plays a prominent role in biocontrol of houseflies, Musca domestica (L.). Thus, a deeper insight into immune response of M. domestica during B. bassiana infection was warranted to assist the production of more efficient mycoinsecticides. The present study investigates changes in protein profile of M. domestica hemolymph serum post B. bassiana infection using two-dimensional difference gel electrophoresis (2D-DIGE) followed by identification of selected proteins by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). The non-infected or control group of flies showed an expression of 54 proteins, while M. domestica infected with B. bassiana expressed a total of 68 hemolymph serum proteins. Thirty three proteins were expressed in both groups of houseflies, whereas 35 proteins were exclusively expressed in infected flies and 21 proteins were exclusively expressed in control flies. Among the 33 proteins which were expressed in both groups of houseflies, 17 proteins showed downregulation, while16 proteins were upregulated in the infected flies compared to the non-infected ones. The results from this study are expected to facilitate better understanding of insect's immune response mechanism.

Relative efficacy of sterile adults in the control of potato tuberworm, Phthorimaea operculella (Zellar)

International Nuclear Information System (INIS)

Rananavare, H.D.; Harwalkar, M.R.; Rahalkar, G.W.

1989-01-01

Effectiveness of releasing sterile males or females alone or both sexes together in the control of potato tuberworm has been experimentally examined. For female, a dose of 30 Krad was adequate to cause near complete sterility. Reduction in progeny production in one generation was 76 per cent when only sterile males were released while female alone or both sexes together were released, it was to the order of 41.9 and 63.2 per cent, respectively. The relative merits of release of sterile adult males or females alone or both sexes together, have been discussed. (author). 12 refs

Sustainable production of housefly (Musca domestica) larvae as a protein-rich feed ingredient by utilizing cattle manure

Science.gov (United States)

Hussein, Mahmoud; Pillai, Viju V.; Goddard, Joshua M.; Park, Hui G.; Kothapalli, Kumar S.; Ross, Deborah A.; Ketterings, Quirine M.; Brenna, J. Thomas; Milstein, Mark B.; Marquis, Helene; Johnson, Patricia A.; Nyrop, Jan P.

2017-01-01

The common housefly, Musca domestica, is a considerable component of nutrient recycling in the environment. Use of housefly larvae to biodegrade manure presents an opportunity to reduce waste disposal while the rapidly assimilated insect biomass can also be used as a protein rich animal feed. In this study, we examine the biodegradation of dairy cattle manure using housefly larvae, and the nutritional value of the resulting larva meal as a feed ingredient. Our results demonstrated that dairy cattle manure presents a balanced substrate for larval growth, and the spent manure showed reductions in concentration of total nitrogen (24.9%) and phosphorus (6.2%) with an overall reduction in mass. Larva yield at an optimum density was approximately 2% of manure weight. Nutritional analysis of M. domestica larva meal showed values comparable to most high protein feed ingredients. Larva meal was 60% protein with a well-balanced amino acid profile, and 20% fat with 57% monounsaturated fatty acids, and 39% saturated fatty acids. Larva meal lacked any significant amount of omega-3 fatty acids. Evaluation of micronutrients in larva meal suggested that it is a good source of calcium and phosphorus (0.5% and 1.1% respectively). The nutritional value of larva meal closely matches that of fishmeal, making it a potentially attractive alternative for use as a protein-rich feed ingredient for livestock and aquaculture operations. PMID:28170420

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

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

Genetic basis of the sterile insect technique

International Nuclear Information System (INIS)

Robinson, A.S.

2005-01-01

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

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

Medfly (Ceratitis capitata Wiedemann) female attractant studies and development of trapping systems for sterility assessment

International Nuclear Information System (INIS)

Vasquez, L.A.; Sponagel, K.

1999-01-01

In four years of research, we evaluated different traps (McPhail, Tephri, Closed-bottom dry trap, Open-bottom dry trap, and Frutect), lures (FA-2 and FA-3 synthetic lures composed of ammonium acetate + putrescine, and ammonium acetate + putrescine + trimethylamine, respectively), and insect retention methods (water, sticky inserts, insecticides) to develop a selective trapping system for female Mediterranean fruit fly (Ceratitis capitata, Wiedemann) sterility assessment. The trapping systems were compared with protein-baited McPhail traps, which are the standard method for C. capitata female capture, during eight to fifteen week trials in coffee and orthanique orange plantations at two different localities in Honduras. Trimedlure-baited Jackson traps were also used as the standard indicator of the C. capitata populations. The Closed-bottom trap baited with the two-component synthetic lure captured eight to twelve times fewer C. capitata than the Jackson trap. The McPhail trap and the modified Open-bottom trap, both baited with the two-component synthetic lure, captured 1.6 to 3.5 times more C. capitata females than the protein-baited McPhail trap. The addition of trimethylamine to the two-component synthetic lure resulted in 9.8 to 15.8 times increases in C. capitata female capture over the protein-baited McPhail trap. The presence of water in McPhail or Tephri traps did not affect the capture of C. capitata females. Throughout the study, all female-targeted trapping systems captured the same proportion of females. (author)

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

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)

Pain Associated With Hysteroscopic Sterilization

Science.gov (United States)

Levy, Jenna; Childers, Meredith E.

2007-01-01

Background and Objectives: The safety and efficacy of female hysteroscopic sterilization using the Essure system has been well documented. Given the marked differences in the execution of hysteroscopic and laparoscopic sterilization, the objective of this study was to assess the experience of pain postprocedure between the 2. Secondary end-points included postoperative pain medication, time to return to normal activities, postprocedure bleeding, and patient satisfaction. Methods: Twenty cases each of laparoscopic sterilization (LS) and hysteroscopic sterilization (HS) were performed. Patients were surveyed regarding their experience of pain immediately postoperatively, 1 week, and 4 weeks post-procedure. Results: The average pain score immediately postprocedure was significantly lower among HS patients than among LS patients (t=−8.17, P<.0001). One-week post-procedure, none of the patients in the HS group reported any pain, while the average pain score among the LS patients was 2.65 (t =−9.67, P<.0001). Four weeks post-procedure, women in the HS group continued to report no pain, 35% of the LS group continued to report some pain (t=−3.04, P=.004). Conclusions: Hysteroscopic sterilization offers a minimally invasive, less painful, equally efficacious modality for sterilization than laparoscopic sterilization and should be available to all women seeking permanent birth control. PMID:17651558

Levels of Cadmium, Chromium and Lead in dumpsites soil, earthworm (Lybrodrilus Violaceous), Housefly (Musca Domestica) and dragon fly (Libellula luctosa)

International Nuclear Information System (INIS)

Adeniyi, A.A.; Okedeyi, O.O.; Idowu, A.B.

2003-01-01

Chemical analyses of cadmium, chromium and lead in dumpsites soil, earthworm (Lybrodrilus violaceous), housefly (Musca domestica) and in indigenous dragonfly (Libellula luctosa) were performed by atomic absorption spectrophotometry to estimate the degree of metal pollution in two Lagos dumpsites located at Iba Housing Estate (dumpsite A) and Soluos along LASU - Isheri road (dumpsite B). Soil pH and moisture content were also determined. Chromium was not detected (ND) in most of the samples except in the soil samples whose mean and standard deviation (SD) were 0.43 Plus minus 0.37 micro g/g and 0.23 plus minus 0.37 micro g/g, respectively for dumpsites A and B, and the earthworm samples harvested from dumpsite B (1.00 plus minus 1.41 micro g/g the cadmium levels were 4.00 plus minus 3.16 micro g/g and 7.50 plus minus 6.37 micro g/g for earthwarm; 2.86 plus minus 1.43 micro g/g and 4.29 plus minus 3.74 micro g/g for housefly, 0.75 plus minus 1.26 micro g/g and 1.25 plus minus 0.95 micro g/g for dragonfly, respectively for dumpsites A and B. However, the concentration of lead in the invertebrates were, 130.00 plus minus 112.58 micro g/g and 105.75 plus minus 94.44 micro g/g for earthworm; 145.71 plus minus 101.87 micro g/g and 225.71 plus minus 79.31 micro g/g for housefly; 165.00 plus minus 69.78 micro g/g and 85.00 plus minus 69.73 micro g/g for dragonfly respectively for dumpsites A and B. Cadmium and lead levels were found to be higher in the invertebrates harvested from the dumpsites than those collected from the non-dumpsites. The non-dumpsite values for cadmium were 1.24 plus minus 0,94 micro g/g, 0.45 plus minus 0.56 micro g/g and 0.38 plus minus 0.4 micro g/g for earthworm, housefly and dragonfly, respectively. Similarly, the non-dumpsite lead levels for earthworm, housefly and dragonfly were 23.12 plus minus 10.11 micro g/g, 20.75 plus minus 11.85 micro g/g and 33.62 plus minus 14.95 micro g/g, respectively.(author)

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

International Nuclear Information System (INIS)

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

1999-01-01

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

Evolution of postmating reproductive isolation: measuring the fitness effects of chromosomal regions containing hybrid male sterility factors.

Science.gov (United States)

Johnson, N A; Wu, C I

1993-08-01

At least six regions of the X chromosome can cause male sterility when introgressed from Drosophila mauritiana into Drosophila simulans. In this article, we present the results of the other fitness effects caused by two X-linked regions that contain hybrid male sterility factors. In both regions, females that are heterozygous for an introgression with such a sterility factor produce substantially-fewer offspring than females heterozygous for an introgression that lacks the sterility factor. Thus, the hybrid male sterility factors, or other genes nearby, have substantial effects on female productivity. In contrast, hybrid male sterility factors have little or no effect on the relative viabilities of either sex. The evolutionary implications of these findings are discussed.

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)

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.

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

International Nuclear Information System (INIS)

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

2014-01-01

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

Comparative mating and reproductive performance of radiation sterilized and radiation induced F1 sterile males of Earias vittella (Fabricius)

International Nuclear Information System (INIS)

Shantharam, K.; Tamhankar, A.J.; Harwalkar, M.R.

1995-01-01

Studies were conducted on mating behaviour and reproductive performance of a) Earias vittella (F.) males rendered sterile by exposing them to 300 Gy gamma rays and b) F 1 sterile males obtained by exposing parent male to 100 Gy gamma rays. For the study, males were allowed only one mating with a normal female. Results revealed that premating period, period in copula and per cent insects mating were not adversely affected in case of both types of sterile males and fecundity also remained unaffected. However, in both types of sterile males, incidence of spermatophore transfer without sperm was very large and such an occurrence (including reduced spermatophore transfer) was significantly higher in case of radiation sterilized males compared to the F 1 sterile males. Inability to produce and transfer spermatophore and/or sperm appeared to be a major cause behind the reduced mating competitiveness of both types of males. (author). 22 refs., 2 tabs

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)

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)

Effect of gamma irradiation on fertility of potato tuber moth males and study of inherited sterility phenomena in partially sterile males

International Nuclear Information System (INIS)

Saour, G.; Makee, H.

1996-01-01

Newly emerged adult males (0-18 h) potato tuber moth (PTM) phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) were irradiated with various doses of gamma irradiation ranging from 5 to 45 krad. Sterility in order of 91% was induced when males were irradiated with a dose of 45 Krad. Longevity of male PTM was not affected by the application of irradiation, while mating ability and frequency of mating of the males irradiated with 25, 35 and 45 Krad were decreased. The mean number of eggs laid by females mated with males irradiated at 35 and 45 Krad was lower than the control. When males PTM were irradiated with high doses their competitiveness values were reduced, while the competitiveness was increased when the sex ratio of irradiated males to normal males was increased, specially with ration 1 : 10 : 1 (Normal male: Irradiated males: Normal female). Application of 15 Krad dose permitted, the ability to obtain a desired level of male sterility with acceptable reduction in its competitiveness. The inherited sterility phenomena in partially sterile males irradiated with 10-15 and 20 Krad was studied. Sterility in F1 progeny was higher than that in their irradiated male parents. The sex ratio of F1 progeny was distorted in favour of the males. (author). 24 refs., 5 figs

Effect of gamma irradiation on fertility of potato tuber moth males and study of inherited sterility phenomena in partially sterile males

Energy Technology Data Exchange (ETDEWEB)

Saour, G; Makee, H [Atomic Energy Commission, Damascus (Syrian Arab Republic). Dept. of Radiation Agriculture

1996-01-01

Newly emerged adult males (0-18 h) potato tuber moth (PTM) phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) were irradiated with various doses of gamma irradiation ranging from 5 to 45 krad. Sterility in order of 91% was induced when males were irradiated with a dose of 45 Krad. Longevity of male PTM was not affected by the application of irradiation, while mating ability and frequency of mating of the males irradiated with 25, 35 and 45 Krad were decreased. The mean number of eggs laid by females mated with males irradiated at 35 and 45 Krad was lower than the control. When males PTM were irradiated with high doses their competitiveness values were reduced, while the competitiveness was increased when the sex ratio of irradiated males to normal males was increased, specially with ration 1 : 10 : 1 (Normal male: Irradiated males: Normal female). Application of 15 Krad dose permitted, the ability to obtain a desired level of male sterility with acceptable reduction in its competitiveness. The inherited sterility phenomena in partially sterile males irradiated with 10-15 and 20 Krad was studied. Sterility in F1 progeny was higher than that in their irradiated male parents. The sex ratio of F1 progeny was distorted in favour of the males. (author). 24 refs., 5 figs.

Evaluation of the efficiency of various medfly female trapping combinations in Costa Rica in support of the sterile insect technique

International Nuclear Information System (INIS)

Camacho, H.

1999-01-01

This report contains information from a four-year research programme co-ordinated by the International Atomic Energy Agency. The objective of the programme was to develop a trapping system for females of the Mediterranean fruit fly (medfly), Ceratitis capitata (Diptera: Tephritidae), for practical use in Sterile Insect Technique (SIT) programs and to design and evaluate a trap to obtain eggs from wild female medflies in order to estimate sterility induction in the field population. The study was carried out at two different Agricultural Research Stations of the University of Costa Rica, the Fabio Baudrit Agricultural Research Station (FBS) and Laguna de Fraijanes Agricultural Research Station (LFS), and in a privately-owned coffee and orange plantation in Grecia canton (Coope-Victoria Farm). Female medfly attractants tested were three food based 'female' attractants (FA-3), namely ammonium acetate (AA), 1,4 diaminobutane (putrescine) and trimethylamine, all formulated to last at least one month. These attractants were evaluated either in combinations of two (AA + putrescine, termed FA-2) or all three (termed FA-3). The attractants were tested in various traps including the plastic International Pheromone's McPhail traps (IPMT) and Tephri traps, a Spanish trap similar to the IPMT. Traps were used either as a dry trap (provided with DDVP) or a wet trap (provided with water and 0.01% surfactant). Jackson traps with Trimedlure (JT,TML), a routinely used male medfly trapping system, was also used. Trapping experiments conducted in the citrus plantation of the FBS resulted in the following fly/trap/day indices (F/T/D): 7.18 with JT,TML; 4.62 with open bottom dry traps (OBDT) baited with FA-3; 4.18 with OBDT (PVC) baited with FA-3; 7.73 with IPMT baited with FA-3, wet; 8.245 with IPMT baited with FA-3, dry; 5.27 with IPMT baited with NuLure; 4.79 with Tephri baited with FA-3, wet; and 5.42 with Tephri, FA-3, dry. The F/T/D indices at the Coope-Victoria Farm, in coffee

Evaluation of the efficiency of various medfly female trapping combinations in Costa Rica in support of the sterile insect technique

Energy Technology Data Exchange (ETDEWEB)

Camacho, H [Laboratorio de Investigacion en Mosca del Mediterraneo, Escuela de Biologia, Universidad de Costa Rica, San Jose (Costa Rica)

1999-07-01

This report contains information from a four-year research programme co-ordinated by the International Atomic Energy Agency. The objective of the programme was to develop a trapping system for females of the Mediterranean fruit fly (medfly), Ceratitis capitata (Diptera: Tephritidae), for practical use in Sterile Insect Technique (SIT) programs and to design and evaluate a trap to obtain eggs from wild female medflies in order to estimate sterility induction in the field population. The study was carried out at two different Agricultural Research Stations of the University of Costa Rica, the Fabio Baudrit Agricultural Research Station (FBS) and Laguna de Fraijanes Agricultural Research Station (LFS), and in a privately-owned coffee and orange plantation in Grecia canton (Coope-Victoria Farm). Female medfly attractants tested were three food based `female` attractants (FA-3), namely ammonium acetate (AA), 1,4 diaminobutane (putrescine) and trimethylamine, all formulated to last at least one month. These attractants were evaluated either in combinations of two (AA + putrescine, termed FA-2) or all three (termed FA-3). The attractants were tested in various traps including the plastic International Pheromone`s McPhail traps (IPMT) and Tephri traps, a Spanish trap similar to the IPMT. Traps were used either as a dry trap (provided with DDVP) or a wet trap (provided with water and 0.01% surfactant). Jackson traps with Trimedlure (JT,TML), a routinely used male medfly trapping system, was also used. Trapping experiments conducted in the citrus plantation of the FBS resulted in the following fly/trap/day indices (F/T/D): 7.18 with JT,TML; 4.62 with open bottom dry traps (OBDT) baited with FA-3; 4.18 with OBDT (PVC) baited with FA-3; 7.73 with IPMT baited with FA-3, wet; 8.245 with IPMT baited with FA-3, dry; 5.27 with IPMT baited with NuLure; 4.79 with Tephri baited with FA-3, wet; and 5.42 with Tephri, FA-3, dry. The F/T/D indices at the Coope-Victoria Farm, in coffee

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)

On the difficulties of discriminating between major and minor hybrid male sterility factors in Drosophila by examining the segregation ratio of sterile and fertile sons in backcrossing experiments.

Science.gov (United States)

Maside, X R; Naveira, H F

1996-10-01

The observation of segregation ratios of sterile and fertile males in offspring samples from backcrossed hybrid females is, in principle, a valid method to unveil the genetic basis of hybrid male sterility in Drosophila. When the female parent is heterozygous (hybrid) for a sterility factor with major effects, equal proportions of fertile and sterile sons are expected in her offspring. However, intact (not recombined) chromosome segments of considerable length are expected to give segregation ratios that can not be easily differentiated from the 1:1 ratio expected from a single factor. When the phenotypic character under analysis can be determined by combinations of minor factors from the donor species spanning a certain chromosome length, very large offspring samples may be needed to test this alternative hypothesis against the null hypothesis of a single major factor. This is particularly the case of hybrid male sterility determinants in Drosophila.

Proteomic Analysis of Pachytene Spermatocytes of Sterile Hybrid Male Mice.

Science.gov (United States)

Wang, Lu; Guo, Yueshuai; Liu, Wenjing; Zhao, Weidong; Song, Gendi; Zhou, Tao; Huang, Hefeng; Guo, Xuejiang; Sun, Fei

2016-09-01

Incompatibilities in interspecific hybrids, such as reduced hybrid fertility and lethality, are common features resulting from reproductive isolation that lead to speciation. Subspecies crosses of house mice produce offspring in which one sex is infertile or absent, yet the molecular mechanisms of hybrid sterility are poorly understood. In this study, we observed extensive asynapsis of chromosomes and disturbance of the sex body in pachytene spermatocytes of sterile F1 males (PWK/Ph female × C57BL/6J male). We report the high-confidence identification of 4005 proteins in the pachytene spermatocytes of fertile F1 males (PWK/Ph male × C57BL/6J female) and sterile F1 males (PWK/Ph female × C57BL/6J male), of which 215 were upregulated and 381 were downregulated. Bioinformatics analysis of the proteome led to the identification of 43 and 59 proteins known to be essential for male meiosis and spermatogenesis in mice, respectively. Characterization of the proteome of pachytene spermatocytes associated with hybrid male sterility provides an inventory of proteins that is useful for understanding meiosis and the mechanisms of hybrid male infertility. © 2016 by the Society for the Study of Reproduction, Inc.

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)

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)

Surgical sterilization of free-ranging wolves.

Science.gov (United States)

Spence, C E; Kenyon, J E; Smith, D R; Hayes, R D; Baer, A M

1999-02-01

The objective of the study was to determine whether surgical sterilization of both males and females in wolf pairs alters basic wolf social and territorial behaviors. Wolves were located from the air by snow-tracking methods and were tranquilizer-darted from a helicopter. Surgeries were performed either in a tent at the capture site or in a heated building in a nearby village. Six vasectomies and seven uterine horn ligations were performed in January and February of 1996 and 1997. Two females died: one likely related to the capture procedure, the other of a peritonitis unrelated to the surgery. One wolf had a litter. None of the wolves have shown changes in behavioral patterns. Surgical sterilization can be effective, but other, less invasive, fertility control techniques should be investigated.

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.

Esterilização feminina: liberdade e opressão Female sterilization: free choice and oppression

Directory of Open Access Journals (Sweden)

Carmen Barroso

1984-04-01

Full Text Available É mostrado que a esterilização feminina tem aumentado extraordinariamente nos últimos anos no Brasil. Em alguns Estados do Nordeste, este é o meio anticoncepcional mais comumente usado, sendo os hospitais estaduais e municipais e o Instituto Nacional de Assistência Médica e Previdência Social (INAMPS os principais fornecedores. Entretanto, em que pese haver numerosos abusos praticados, de esterilizações realizadas sem o consentimento consciente da mulher, é provável que grande parte das esterilizações tenha sido solicitada pelas clientes, mas dentro de um conjunto de alternativas que elas individualmente são impotentes para alterar. Estas alternativas decorrem de determinantes sociais: posição desvantajosa da mulher na família e no mercado de trabalho, a cultura patriarcal, a política de mercantilização da saúde e a política demográfica.Female sterilization has increased extraordinarily in the last few years in Brazil. In some Northeastern States, it is already the most common contraceptive method used, as it is provided by state and municipal hospitals and National Institute of Medical and Social Welfare. In spite of a large number of abuses, when women are sterilized without their informed consent, it is likely that a large proportion of sterilizations are actively sought by clients. However, this happens in response to a series of options which the women, as individuals, are powerless to change. These options arise from social determinative factors such as: the disavantages of the woman's position in the family and in the labor market, the patriarchal culture, commoditization of health and demographic policies.

Radiation sterilization of the greenhouse white fly (Trialeurodes vaporariorum Westw., Homoptera, Aleyrodidae). Part 2

International Nuclear Information System (INIS)

Genchev, N.

1987-01-01

Results are reported of studies of the sterilizing effect on puparia and imagoes of the greenhouse white fly (T. vaporariorum). The irradiation was made by gamma rays at the rate of 12+-5% rad/s. The parameters of radiation-induced sterility were sex determined. The sterilizing effect was expressed in emergence of dominant lethal mutations in spermatozoa accompanied by partial sperm inactivation and of partial aspermia. The absolute sterilizing doses for the two ontogenetic stage are 6 and 7 krad respectively. Radiation induced sterilization of the male parent resulted in forced arrhenotoky in F 1 and was regarded as a transformation of parthogenesis factor necessary for the normal propagation in the insect process into one that is lethal to the population factor. Radiation induced female sterility in females was expressed in the emergence of dominant lethals in oocytes. The absolute sterilizing doses for the puparium and the imago were 5 and 6 krad, respectively. Doses ≥4 krad caused partial infertility

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

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

Science.gov (United States)

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

2016-02-01

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

Mass-rearing for sterile insect release

International Nuclear Information System (INIS)

Parker, A.G.

2005-01-01

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

Non-surgical female sterilization with quinacrine-induced tubal occlusion: a clinical trial

Directory of Open Access Journals (Sweden)

Seifi

2008-08-01

Full Text Available Background: Over the last 35 years, quinacrine has been used to sterilize more than 150,000 women in 40 countries, first in the form of slurry and now in the form of cylindrical pellets. Some studies confirmed the tubal occlusion by hysterosalpyngo-graphy, but this method increases the chance of failure. Only a few studies on tubal occlusion have used transvaginal sonography for confirmation, and there were some doubts about the effect of quinacrine on the endometrium. We performed this study to evaluate the tubal scar and endometrial pattern by ultrasound and to determine the feasibility, acceptance, and side effects of quinacrine sterilization (QS in Iranian women. Methods: This prospective clinical trial was done at the Vali-e-Asr Reproductive Health Research Center of the Tehran University of Medical Sciences between April 2005 and July 2006. One hundred sexually active women ranging from 30 to 47 years of age, who had at least two children above two years old, requesting sterilization, were sterilized by this method. By the end of menstrual bleeding, seven pellets, each containing 36mg quinacrine, were inserted in the uterine fundal area via the cervical canal. The procedure was repeated one month later. Three cycles after the first step, transvaginal sonography was performed to visualize the tubal scar and determine the endometrial pattern. Patients were followed at one and three years after initiation of the procedure. Results: All women were satisfied with the procedure. There were no side effects. No pregnancies had occurred, nor were there endometrial thickness abnormalities. Scar formation was visible in the tubes. "nConclusion: Quinacrine sterilization is a useful method for women and can be recommended to family planning services as an ambulatory procedure due to its efficacy, simplicity, acceptance and cost effectiveness.

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.)

Resistance risk assessment of 2 insect development inhibitors, diflubenzuron and cyromazine, for control of the housefly musca-domestica l

DEFF Research Database (Denmark)

Keiding, J.; El-Khodary, A.S.; Jespersen, Jørgen B.

1992-01-01

pressure is compared with other investigations and discussed. Moderate to high resistance to DFB or CYR can develop in housefly populations if the selection pressure is strong, especially when used as feed-through applications on poultry farms where all feed contains DFB or CYR. If the treatment of fly...

Hysteroscopic tubal sterilization: a systematic review of the Essure system

DEFF Research Database (Denmark)

Hurskainen, Ritva; Hovi, Sirpa-Liisa; Gissler, Mika

2010-01-01

OBJECTIVE: To update the evidence of the efficacy and safety of the Essure system. Female sterilization has undergone changes in the last decade. Besides laparoscopic tubal occlusion, the Essure system is now a viable option, with about 200,000 women sterilized using this method. DESIGN: The review...... in ambulatory settings. However, sterilization is not immediate and women must use additional contraception for 3 months until permanent tubal occlusion is verified by transvaginal ultrasound, hysterosalpingosonography, hysterosalpingography, or pelvic radiography. The evidence on efficacy and safety is mainly...... sterilization, but more information on the total cost is needed. CONCLUSION(S): The Essure system appears to be safe, permanent, irreversible, and a less invasive method of contraception compared with laparoscopic sterilization. Copyright (c) 2010 American Society for Reproductive Medicine. Published...

Genetic complexity underlying hybrid male sterility in Drosophila.

OpenAIRE

Sawamura, Kyoichi; Roote, John; Wu, Chung-I; Yamamoto, Masa-Toshi

2004-01-01

Recent genetic analyses of closely related species of Drosophila have indicated that hybrid male sterility is the consequence of highly complex synergistic effects among multiple genes, both conspecific and heterospecific. On the contrary, much evidence suggests the presence of major genes causing hybrid female sterility and inviability in the less-related species, D. melanogaster and D. simulans. Does this contrast reflect the genetic distance between species? Or, generally, is the genetic b...

Sterilization of DACUS CUCUMIS FRENCH (DIPTERA:TEPHRITIDAE) by gamma radiation

International Nuclear Information System (INIS)

Hooper, G.H.S.

1975-01-01

The effect of gamma radiation administered to newly emerged adults of Dacus cucumis French on sterility and competitiveness was evaluated. A dose of 11 krad caused almost complete sterility in males while females given 6 krad were totally sterile, through infecundity. Sterilized males showed reduced competitiveness. In competitive mating tests a dose of 7 krad gave the lowest egg hatch and this hatch was significantly lower than that given by 9 and 11 krad. In a paired comparison mating test, 7 and 9 krad treated males mated significantly less frequently than untreated males, but the ability of 6 krad treated males was unimpared. (author)

Perturbation in protein expression of the sterile salmonid hybrids between female brook trout Salvelinus fontinalis and male masu salmon Oncorhynchus masou during early spermatogenesis.

Science.gov (United States)

Zheng, Liang; Senda, Yoshie; Abe, Syuiti

2013-05-01

Most males and females of intergeneric hybrid (BM) between female brook trout (Bt) Salvelinus fontinalis and male masu salmon (Ms) Oncorhynchus masou had undeveloped gonads, with abnormal germ cell development shown by histological examination. To understand the cause of this hybrid sterility, expression profiles of testicular proteins in the BM and parental species were examined with 2-DE coupled with MALDI-TOF/TOF MS. Compared with the parental species, more than 60% of differentially expressed protein spots were down-regulated in BM. A total of 16 up-regulated and 48 down-regulated proteins were identified in BM. Up-regulated were transferrin and other somatic cell-predominant proteins, whereas down-regulated were some germ cell-specific proteins such as DEAD box RNA helicase Vasa. Other pronouncedly down-regulated proteins included tubulins and heat shock proteins that are supposed to have roles in spermatogenesis. The present findings suggest direct association of the observed perturbation in protein expression with the failure of spermatogenesis and the sterility in the examined salmonid hybrids. Copyright © 2013 Elsevier B.V. All rights reserved.

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.

A synthetic combination of mutations, including fs(1)pyrSu(b), rSu(b) and b, causes female sterility and reduces embryonic viability in Drosophila melanogaster

DEFF Research Database (Denmark)

Piskur, Jure; Gojkovic, Zoran; Bahn, E.

1999-01-01

A Drosophila melangaster mutant, fs(1)pyr(Su(b)), carrying a mutation that maps to the tip of the X chromosome, has been isolated. The mutation, when present alone, does not confer a detectable phenotype. However, this mutation causes female sterility and reduces embryonic viability when combined...

Construction of a male sterility system for hybrid rice breeding and seed production using a nuclear male sterility gene.

Science.gov (United States)

Chang, Zhenyi; Chen, Zhufeng; Wang, Na; Xie, Gang; Lu, Jiawei; Yan, Wei; Zhou, Junli; Tang, Xiaoyan; Deng, Xing Wang

2016-12-06

The breeding and large-scale adoption of hybrid seeds is an important achievement in agriculture. Rice hybrid seed production uses cytoplasmic male sterile lines or photoperiod/thermo-sensitive genic male sterile lines (PTGMS) as female parent. Cytoplasmic male sterile lines are propagated via cross-pollination by corresponding maintainer lines, whereas PTGMS lines are propagated via self-pollination under environmental conditions restoring male fertility. Despite huge successes, both systems have their intrinsic drawbacks. Here, we constructed a rice male sterility system using a nuclear gene named Oryza sativa No Pollen 1 (OsNP1). OsNP1 encodes a putative glucose-methanol-choline oxidoreductase regulating tapetum degeneration and pollen exine formation; it is specifically expressed in the tapetum and miscrospores. The osnp1 mutant plant displays normal vegetative growth but complete male sterility insensitive to environmental conditions. OsNP1 was coupled with an α-amylase gene to devitalize transgenic pollen and the red fluorescence protein (DsRed) gene to mark transgenic seed and transformed into the osnp1 mutant. Self-pollination of the transgenic plant carrying a single hemizygous transgene produced nontransgenic male sterile and transgenic fertile seeds in 1:1 ratio that can be sorted out based on the red fluorescence coded by DsRed Cross-pollination of the fertile transgenic plants to the nontransgenic male sterile plants propagated the male sterile seeds of high purity. The male sterile line was crossed with ∼1,200 individual rice germplasms available. Approximately 85% of the F1s outperformed their parents in per plant yield, and 10% out-yielded the best local cultivars, indicating that the technology is promising in hybrid rice breeding and production.

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)

Postpartum Sterilization

Science.gov (United States)

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

Overcoming inter-subspecific hybrid sterility in rice by developing indica-compatible japonica lines.

Science.gov (United States)

Guo, Jie; Xu, Xiaomei; Li, Wentao; Zhu, Wenyin; Zhu, Haitao; Liu, Ziqiang; Luan, Xin; Dai, Ziju; Liu, Guifu; Zhang, Zemin; Zeng, Ruizhen; Tang, Guang; Fu, Xuelin; Wang, Shaokui; Zhang, Guiquan

2016-06-01

Rice (Oryza sativa L.) is an important staple crop. The exploitation of the great heterosis that exists in the inter-subspecific crosses between the indica and japonica rice has long been considered as a promising way to increase the yield potential. However, the male and female sterility frequently occurred in the inter-subspecific hybrids hampered the utilization of the heterosis. Here we report that the inter-subspecific hybrid sterility in rice is mainly affected by the genes at Sb, Sc, Sd and Se loci for F1 male sterility and the gene at S5 locus for F1 female sterility. The indica-compatible japonica lines (ICJLs) developed by pyramiding the indica allele (S-i) at Sb, Sc, Sd and Se loci and the neutral allele (S-n) at S5 locus in japonica genetic background through marker-assisted selection are compatible with indica rice in pollen fertility and in spikelet fertility. These results showed a great promise of overcoming the inter-subspecific hybrid sterility and exploiting the heterosis by developing ICJLs.

The causes of genetic male sterility in 3 soybaen lines.

Science.gov (United States)

Rubaihayo, P R; Gumisiriza, G

1978-11-01

The cause of male sterility in 3 soybean lines, TGM 103-1, N-69-2774 and TGM 242-4 was studied. In TGM 103-1, which was both male and female sterile, two different abnormalities were associated with sterility. Precocious movement of a few chromosomes at the metaphase I stage resulted into the production of non-functional pollen while cells which underwent apparent normal meiotic division had disintergration of the tapetal cell wall immediately after the free microspore stage leading to the starvation and subsequent death of the developing microspores. In lines N-69-2774 and TGM 242-4, both of which were partially sterile, male sterility resulted from a failure of cytokinesis after the telophase II stage. Meiosis proceeded normally but the 4 microspores after telophase II failed to separate into pollen grains and degenerated thereafter.

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

Sterilization of full grown pupae of the long headed flour beetle with gamma radiation and its effect on mating competitiveness

International Nuclear Information System (INIS)

Ahmed, M.Y.Y.; Aboul-Nasr, A.E.; Abdel-Rahmal, A.M.; Ahmed, Z.A.

1985-01-01

When fully grown pupae of Lathyticus oryzae were irradiated at 8Krad, the resulting adults were completely sterile. When sterile males were added to the unirradiated males and females ratios of 1:1:1, 5:1:1, 10:1:1 and 15:1:1, the percentage of egg hatch decreased from 79.2 for the controls to 48.1 at the ratio of 1:1:1. Male competitiveness value for this ratio was 0.64. Increasing the ratio to 15:1:1 decreased percentage of egg hatch to 4.0. The competitiveness value at this ratio was 1.3 (i.e. the sterile males were fully competitive). The effects of releasing both sterile males and females were also investigated. The present results indicated that release of sterile females together with sterile males give good results, especially with flooding ratio 15:15:1:1, which gave 98.3% infertility in the resulting eggs. The competitiveness value showed that the sterile adults were fully competitive with normal adults at this flooding ratio

Surgical sterilization of free-ranging wolves.

OpenAIRE

Spence, C E; Kenyon, J E; Smith, D R; Hayes, R D; Baer, A M

1999-01-01

The objective of the study was to determine whether surgical sterilization of both males and females in wolf pairs alters basic wolf social and territorial behaviors. Wolves were located from the air by snow-tracking methods and were tranquilizer-darted from a helicopter. Surgeries were performed either in a tent at the capture site or in a heated building in a nearby village. Six vasectomies and seven uterine horn ligations were performed in January and February of 1996 and 1997. Two females...

Hysteroscopic Sterilization

Science.gov (United States)

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

Gender variation, partial male sterility and labile sex expression in gynodioecious Plantago coronopus

NARCIS (Netherlands)

Koelewijn, HP; VanDamme, JMM

Gynodioecy is a breeding system consisting of male steriles (MS, females) and hermaphrodites (H). There is however within such sq stems a third, often neglected, class of partially male sterile plants (PMS), i.e. plants with an intermediate sex expression. In natural populations of Plantago

Gender variation, partial male sterility and labile sex expression in gynodioecious Plantago coronopus

NARCIS (Netherlands)

Koelewijn, H.P.; Van Damme, J.M.M.

1996-01-01

Gynodioecy is a breeding system consisting of male steriles (MS, females) and hermaphrodites (H). There is however within such sq stems a third, often neglected, class of partially male sterile plants (PMS), i.e. plants with an intermediate sex expression. In natural populations of Plantago

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

The effect of methyl eugenol exposure on subsequent mating performance of sterile males of the oriental fruit fly, Bactrocera dorsalis

International Nuclear Information System (INIS)

Ji Qing'e; Guo Qingliang; Chen Jiahua

2011-01-01

The effect of methyl eugenol (ME) on the total times of mating, consecutive mating, mating competitiveness, multiple mating, and the incidence of wild female remating were studied in sterile males from a genetic sexing strain of Bactrocera dorsalis (Hendel). Male pupae were irradiated at dose of 100 Gy by 137 Cs at 2 d before emergence and the dose rate was 1.00 Gy/min. Sexually mature 10 day old sterile males were fed ME, while Non-ME-fed sterile males and normal wild males were used as control, and wild females as mating partners. The results showed that some ME-fed sterile males could mate continuously up to nine times, but the total times of consecutive mating and the mean value of continuous mating times were not significant (P > 0.05) compared with the control. The total mating times of ME-fed sterile males was 344.33 ± 12.55 and the mean value was 6.88 ± 0.25, but both have no significant difference compared with the control. The mating success rate of ME-fed and non-ME-fed sterile males mated with wild females were 44.67 ± 2.40% and 22.00 ± 2.31% separately. There were significant differences between them (t = -6.8, P = 0.002). The outcomes were that feeding on ME did not increase the frequency of multiple mating by sterile males, but significantly increased the mating competitiveness of sterile males against wild males. At the same time, sterile males fed ME did not significantly affect the remating of wild females 5 days after the initial mating, but increased the remating frequency of females 10 and 15 days after the initial mating. (authors)

The effect of methyl eugenol exposure on subsequent mating performance of sterile males of the oriental fruit fly, bactrocera dorsalis

International Nuclear Information System (INIS)

Ji Qing'e; Guo Qingliang; Chen Jiaye

2012-01-01

The effect of methyl eugenol (ME) on the total times of mating, consecutive mating, mating competitiveness, multiple mating, and the incidence of wild female remating were studied in sterile males from a genetic sexing strain of Bactrocera dorsalis (Hendel). Male pupae were irradiated at dose of 100 Gy by 137 Cs at 2 d before emergence and the dose rate was 1.00 Gy/min. Sexually mature 10 day old sterile males were fed ME, while Non-ME-fed sterile males and normal wild males were used as control, and wild females as mating partners. The results showed that some ME-fed sterile males could mate continuously up to nine times, but the total times of consecutive mating and the mean value of continuous mating times were not significant (P> 0.05) compared with the control. The total mating times of ME-fed sterile males was 344.33±12.55 and the mean value was 6.88±0.25, but both have no significant difference compared with the control. The mating success rate of ME-fed and non- ME-fed sterile males mated with wild females were (44.67±2.40)% and (22.00±2.31)% separately. There were significant differences between them (t = -6.8, P = 0.002). The outcomes were that feeding on ME did not increase the frequency of multiple mating by sterile males, but significantly increased the mating competitiveness of sterile males against wild males. At the same time, sterile males fed ME did not significantly affect the remating of wild females 5 days after the initial mating, but increased the remating frequency of females 10 and 15 days after the initial mating. (authors)

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.

Interspecific Mating between Wild and Sterile Fruit Flies of Oriental Fruit Fly, Bactrocera dorsalis (Hendel) with Guava Fruit Fly, Bactrocera correcta (Bezzi) in Cages

International Nuclear Information System (INIS)

Pransopon, Prapon; Sutantawong, Manon

2003-06-01

Copulation and sperm transfer were observed between wild flies and sterile flies of Bactrocera dorsalis (Hendel) and Bactrocera correcta (Bezzi) in cages. 8-day old pupae of B. dorsalis and B. correcta were irradiated with gamma rays at 90 and 80 gray respectively. Wild flies from infested fruits and sterile flies from artificial diet in the labolatory were used for testing. The experiments were conducted 3 treatments and 3 replications. The ratio of sterile male : wild male: wild female were 3:1:1 by using sterile male of B. dorsalis: wild male of B. correcta : wild female of B. correcta and sterile male of B. correcta: wild male of B. dorsalis: wild female of B. dorsalis as 60:20:20 flies respectively. The experiment found 69 pairs of copulation consisting of 3 mating pairs(4.3%) of wild male with wild female of B. dorsalis, 22 mating pairs (31.9%) of wild male with wild female of B. correcta, 2 mating pairs(2.9%) of sterile male of B dorsalis with wild female of B. correcta, 42 mating pairs(60.9%) of sterile male of B. correcta with wild female of B. dorsalis. The cages which ratio 1:1 consisted of wild B. dorsalis and wild B. correcta (male and female = 50:50 flies) were observed and found that 43 pairs of copulation such as 2 mating pairs (4.6%) of wild male with wild female of B. dorsalis, 26 mating pairs (60.5%) of wild male with wild female of B. correcta, 2 mating pairs(2.9%) of sterile male of B. dorsalis with wild female of B. correcta and 15 mating pairs(34.9%) of wild male of B. correcta with wild female of B. dorsalis. Mated female flies were separated from male flies. Egg hatch and sperm were checked. The hatchability of normal copulation of B. dorsalis and B. correcta were 81 and 90%. The average sperm level in spermathecae of normal copulation of B. dorsalis and B. correcta were 2.2 and 2.3 respectively but had no sperm in their spemathecae of females of interspecific copulations Mating behavior of both species began in the evening before sunset at

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

Trends in sterilization since the introduction of Essure hysteroscopic sterilization.

Science.gov (United States)

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

2009-01-01

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

"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.

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

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

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

Complete depletion of primordial germ cells in an All-female fish leads to Sex-biased gene expression alteration and sterile All-male occurrence.

Science.gov (United States)

Liu, Wei; Li, Shi-Zhu; Li, Zhi; Wang, Yang; Li, Xi-Yin; Zhong, Jian-Xiang; Zhang, Xiao-Juan; Zhang, Jun; Zhou, Li; Gui, Jian-Fang

2015-11-18

Gynogenesis is one of unisexual reproduction modes in vertebrates, and produces all-female individuals with identical genetic background. In sexual reproduction vertebrates, the roles of primordial germ cells on sexual dimorphism and gonadal differentiation have been largely studied, and two distinct functional models have been proposed. However, the role of primordial germ cells remains unknown in unisexual animals, and it is also unclear whether the functional models in sexual reproduction animals are common in unisexual animals. To solve these puzzles, we attempt to utilize the gynogenetic superiority of polyploid Carassius gibelio to create a complete germ cell-depleted gonad model by a similar morpholino-mediated knockdown approach used in other examined sexual reproduction fishes. Through the germ cell-depleted gonad model, we have performed comprehensive and comparative transcriptome analysis, and revealed a complete alteration of sex-biased gene expression. Moreover, the expression alteration leads to up-regulation of testis-biased genes and down-regulation of ovary-biased genes, and results in the occurrence of sterile all-males with testis-like gonads and secondary sex characteristics in the germ cell-depleted gynogenetic Carassius gibelio. Our current results have demonstrated that unisexual gynogenetic embryos remain keeping male sex determination information in the genome, and the complete depletion of primordial germ cells in the all-female fish leads to sex-biased gene expression alteration and sterile all-male occurrence.

Objections to tubal sterilization: what reversibility can and cannot overcome.

Science.gov (United States)

Shain, R N

1980-09-01

In a study of 1074 women, 696 and 338 subjects would not seriously consider permanent and hypothetically reversible sterilization, respectively; they were asked to explain their feelings. The reason accounting for most objections to permanent sterilization (65%) was irreversibility and of the subjects who would not consider reversible sterilization or were unsure, 42.7% attributed their principal objection to unnecessary surgery, a factor at least currently intrinsic to the procedure and not readily overcome by education. Many of the remaining objections to both permanent and reversible sterilization may be amenable to change either through education or financial subsidies. In response to a question concerning female attractiveness subsequent to permanent sterilization, 3% of the sample felt attractiveness would decrease and 17.5% were unsure of the surgery's effect. Unsure responses were largely negative in character. This issue is important because of its relationship to intention to undergo sterilization. Upon consideration of reversible sterilization, negative and unsure responses significantly declined, even on the part of those women whose friends have had a poor experience with currently available procedures. Thus, whereas the option of reversibility cannot overcome objections to surgery, it does overcome those regarding permanency; moreover, the "temporary" character it bestows upon surgical sterilization appears to help certain individuals overcome their fears of losing their physical appeal as a result of such procedures.

A simple genetic incompatibility causes hybrid male sterility in mimulus.

Science.gov (United States)

Sweigart, Andrea L; Fishman, Lila; Willis, John H

2006-04-01

Much evidence has shown that postzygotic reproductive isolation (hybrid inviability or sterility) evolves by the accumulation of interlocus incompatibilities between diverging populations. Although in theory only a single pair of incompatible loci is needed to isolate species, empirical work in Drosophila has revealed that hybrid fertility problems often are highly polygenic and complex. In this article we investigate the genetic basis of hybrid sterility between two closely related species of monkeyflower, Mimulus guttatus and M. nasutus. In striking contrast to Drosophila systems, we demonstrate that nearly complete hybrid male sterility in Mimulus results from a simple genetic incompatibility between a single pair of heterospecific loci. We have genetically mapped this sterility effect: the M. guttatus allele at the hybrid male sterility 1 (hms1) locus acts dominantly in combination with recessive M. nasutus alleles at the hybrid male sterility 2 (hms2) locus to cause nearly complete hybrid male sterility. In a preliminary screen to find additional small-effect male sterility factors, we identified one additional locus that also contributes to some of the variation in hybrid male fertility. Interestingly, hms1 and hms2 also cause a significant reduction in hybrid female fertility, suggesting that sex-specific hybrid defects might share a common genetic basis. This possibility is supported by our discovery that recombination is reduced dramatically in a cross involving a parent with the hms1-hms2 incompatibility.

Radiobiology of Small Hive Beetle (Coleoptera: Nitidulidae) and Prospects for Management Using Sterile Insect

International Nuclear Information System (INIS)

Downey, Danielle; Chun, Stacey; Follett, Peter

2016-01-01

Small hive beetle, Aethina tumida Murray (Coleoptera: Nitidulidae), is considered a serious threat to beekeeping in the Western Hemisphere, Australia, and Europe mainly due to larval feeding on honey, pollen, and brood of the European honeybee, Apis mellifera L. Control methods are limited for this pest. Studies were conducted to provide information on the radiobiology of small hive beetle and determine the potential for sterile insect releases as a control strategy. Adult males and females were equally sensitive to a radiation dose of 80 Gy and died within 5–7 d after treatment. In reciprocal crossing studies, irradiation of females only lowered reproduction to a greater extent than irradiation of males only. For matings between unirradiated males and irradiated females, mean reproduction was reduced by >99% at 45 and 60 Gy compared with controls, and no larvae were produced at 75 Gy. Irradiation of prereproductive adults of both sexes at 45 Gy under low oxygen (1–4%) caused a high level of sterility (>99%) while maintaining moderate survivorship for several weeks, and should suffice for sterile insect releases. Sterile insect technique holds potential for suppressing small hive beetle populations in newly invaded areas and limiting its spread. (author)

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

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

Laboratory studies of radiation-induced sterility on the onion maggot, delia antiqua (diptera: anthomyiidae)

International Nuclear Information System (INIS)

McEwen, F.L.; Ritchey, G.; Liu, H.J.

1984-01-01

A dose of 4 krad was the most appropriate for sterilizing pupae of Delia antiqua (Meigen) for field release: adult emergence was not reduced, emerging female flies were sterile, and the eggs produced by normal females which had mated with males irradiated as pupae had a lower hatch than those resulting from matings with normal males. Males irradiated as 6- to 8-day-old pupae were fully competitive under laboratory conditions. Continuous scrutiny of laboratory cultures to detect reduction in adult emergence or reduced competitiveness of males is stressed

Voluntary sterilization in Serbia: Unmet need?

Directory of Open Access Journals (Sweden)

Rašević Mirjana M.

2002-01-01

Full Text Available Is voluntary sterilization as a birth control method accepted in Serbia? This is certainly a question that is being imposed for research, regardless of the fact that voluntary sterilization is neither accessible nor promoted. Most importantly because there is no understanding in the social nor political sphere for legalization of voluntary sterilization as a form of birth control, apart from the clear necessity for this, first, step. They are: the recognition that voluntary sterilization is an efficient and safe birth control method, respectability of basic human as well as sexual and reproductive rights, spreading of sterilization as a form of birth control among population of both developed and developing countries and an epidemic diffusion of repeated induced abortions in Serbia. Thus individual recognition of the advantages of relying on voluntary sterilization, in a non-encouraging atmosphere, certainly represents one more argument to enable couples to prevent conception by sterilization. Since it was impossible to carry out a representative research among the population of men and women who are at risk for conception, an attempt was made to obtain a reply to the set question among women who decided to induce abortion. It was done out of at least two reasons. The first being that women with induced abortion in their reproductive history were the target group for voluntary sterilization. The second reason was based on the assumption that bringing a decision on induced abortion is preceded by the reconsideration of an earlier adopted strategy regarding children, giving birth and contraception and thus its rational component is revealed more and therefore more easily measurable. The research was carried out in the University Clinic of Obstetrics and Gynecology 'Narodni front' in Belgrade from January 21st o March 1st 2002, and included 296 women. By comparing the social and demographic characteristics of the female respondents, as well as

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

Induction of sterility in Anastrepha Fraterculus (Diptera: Tephritidae) by gamma radiation

International Nuclear Information System (INIS)

Allinghi, A.; Gramajo, C.; Willink, E.; Vilardi, J.

2007-01-01

In relation to the application of the sterile insect technique (SIT) for the South American fruit fly Anastrepha fraterculus (Wiedemann), we analyzed the effect on adult fertility of different doses of gamma irradiation and the age of pupae at the time of irradiation. In a first experiment, we applied doses of 50, 70, and 90 Gy to pupae at 24, 48, 72, and 96 h before adult emergence. In a second experiment we irradiated pupae 48 h before emergence with 20, 40, and 60 Gy and estimated male and female fertility and sperm transfer by irradiated males. The results indicated pupal age at irradiation does not significantly affect male fertility. If males irradiated with 60 Gy are crossed to non-irradiated females the fertility is about 1%. Females irradiated with 40 Gy did not lay eggs independently of the male to which they mated. No significant effects of radiation were observed with respect to the ability of males to transfer sperm. A dose of 70 Gy applied 48 h before adult emergence induces 100% sterility in both males and females. (author) [es

Radiation sterilization

International Nuclear Information System (INIS)

Jacobs, G.P.

1989-01-01

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

Induced pollen sterility in petunia. Mode of inheritance and tapetal behavior

International Nuclear Information System (INIS)

Singh, I.S.

1975-01-01

A study was undertaken to investigate the characteristics of different mutants for induced pollen sterility in Petunia hybrida Hort. The F 1 hybrid zygotes (TL-h 1 #female# x Sf-la #male#) were exposed to a 0.2% solution of ethyl methane sulfonate and to 0.75kR of 60 Co gamma rays. Their seeds were sown and pollen sterile plants were observed in the M 1 . The pattern of inheritance in the F 2 and the backcrosses of some selected pollen sterile M 1 mutants showed that sterility mutations had been induced. Whether the mutations are recessive or dominant is not yet known, but it has been shown that they act through the sporophytic tissues. Morphological and cytological observations on four highly sterile M 1 plants showed a similar abnormal behavior of the tapetum. The tapetum of the pollen sterile anthers was thicker, more vacuolated and did persist until a later stage than those in fertile anthers. It is suggested that the persistence of the tapetum after a certain stage blocks the trophic process required for the development of the microspore into viable pollen, and the cause of pollen abortion is sporophytic even when no inheritance of the sterility is observed [fr

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.

Hysteroscopic tubal sterilization: a systematic review of the Essure system.

Science.gov (United States)

Hurskainen, Ritva; Hovi, Sirpa-Liisa; Gissler, Mika; Grahn, Riitta; Kukkonen-Harjula, Katriina; Nord-Saari, Merja; Mäkelä, Marjukka

2010-06-01

To update the evidence of the efficacy and safety of the Essure system. Female sterilization has undergone changes in the last decade. Besides laparoscopic tubal occlusion, the Essure system is now a viable option, with about 200,000 women sterilized using this method. The review is based on the report of the Alberta Heritage Foundation for Medical Research and completed with systematic literature searches up to April 8, 2008. The Managed Uptake of Medical Methods program of the Finnish National Research and Development Center for Health and Welfare. Women over 30 years, who had been sterilized by the Essure method. Hysteroscopic tubal sterilization using Essure system. Efficacy/effectiveness, adverse events, costs. Sterilization by Essure can be performed under local anesthesia or with oral analgesics in ambulatory settings. However, sterilization is not immediate and women must use additional contraception for 3 months until permanent tubal occlusion is verified by transvaginal ultrasound, hysterosalpingosonography, hysterosalpingography, or pelvic radiography. The evidence on efficacy and safety is mainly available from short follow-up case series but shows good efficacy and safety of the Essure system. Only a few small risks are associated with the procedure. Two economic studies, one of which implemented Essure as an in-office procedure, suggest that Essure could be more cost-effective than laparoscopic sterilization, but more information on the total cost is needed. The Essure system appears to be safe, permanent, irreversible, and a less invasive method of contraception compared with laparoscopic sterilization. Copyright (c) 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Sterile neutrino

International Nuclear Information System (INIS)

Anon.

2007-01-01

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

Gamma-sterilization

International Nuclear Information System (INIS)

Lindgren, E.

1974-01-01

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

Plant's sterilization rule for fertile women cited.

Science.gov (United States)

1979-01-01

The American Cyanamid Corporation has been cited by the Occupational Safety and Health Administration (OSHA) for violating federal law by requiring female employees of childbearing age to be sterilized in order to continue working in areas of the plant where they would be exposed to high levels of airborne lead. High levels of airborne lead can cause damage to workers' reproductive systems and be responsible for birth defects in fetuses. The OSHA charged that American Cyanamid's policy constituted a "willful violation" of the 1970 Occupational Safety and Health Act. The Act requires employers to provide employment that is free from recognized hazards likely to cause death or physical harm. According to OSHA, the Act does not allow an employer to eliminate the hazard by compelling employees to choose between losing their jobs and undergoing sterilization. The reproductive health of workers is considered a valid part of OSHA's regulatory concern. The citation, which carries a $10,000 fine, grew out of a complaint that was filed by the Oil, Chemical and Atomic Workers Union on behalf of 5 female workers working in the lead pigment division of the company's Willow Island, West Virginia plant. The 5 employees alleged that they had themselves sterilized to avoid being transferred to other and possibly lower paying janitorial jobs or losing thier jobs completely. The company is appealing the citation. The union has also filed a complaint with the Equal Employment Opportunity Commission charging American Cyanamid with sex discrimination, since only the women workers are at risk of being transferred to lower paying jobs.

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)

Sex chromosome abnormalities and sterility in river buffalo.

Science.gov (United States)

Di Meo, G P; Perucatti, A; Di Palo, R; Iannuzzi, A; Ciotola, F; Peretti, V; Neglia, G; Campanile, G; Zicarelli, L; Iannuzzi, L

2008-01-01

Thirteen male river buffaloes, 119 females with reproductive problems (which had reached reproductive age but had failed to become pregnant in the presence of bulls) and two male co-twins underwent both clinical and cytogenetic investigation. Clinical analyses performed by veterinary practitioners revealed normal body conformation and external genitalia for most females. However, some subjects showed some slight male traits such as large base horn circumference, prominent withers and tight pelvis. Rectal palpation revealed damage to internal sex adducts varying between atrophy of Mullerian ducts to complete lack of internal sex adducts (with closed vagina). All bulls had normal karyotypes at high resolution banding, while 25 animals (23 females and 2 male co-twins) (20.7%) with reproductive problems were found to carry the following sex chromosome abnormalities: X monosomy (2 females); X trisomy (1 female); sex reversal syndrome (2 females); and free-martinism (18 females and 2 males). All female carriers were sterile. Copyright 2008 S. Karger AG, Basel.

Ephestia Kuehniella Z.: Gamma irradiation effects on the adult stage and mating competitiveness of sterile males

International Nuclear Information System (INIS)

Ahmed, M.Y.Y.; El-Banby, M.A.; Salem, Y.S.; Abdel-Baky, S.M.

1985-01-01

Effects of gamma radiation dosages from 5 to 50 Krad on the adult stage of Ephestia Kuehielia Z. were studied. Irradiated adults paired with untreated adults produced fewer eggs than pairs of unirradiated adults, and these eggs had reduced hatch. This effect was more pronounced with irradiated females or when both parents were irradiated. Radiation greatly reduced life span of treated adults. Adult females were more sensitive to the sterilizing effect of gamma radiation than were males. Males were sterilized when irradiated at 50 Krad, but females at 25 Krad. Previous studies showed that males irradiated as fully grown pupae at 45 Krad were completely sterile. When irradiated (I) males were confined with unirradiated (U) males and females (1:1:1 ratio), infertility of eggs was 48%. Increasing the ratio to 5:1:1, 10:1:1 and 15:1:1 caused 77.9, 84.6 and 94.4 percent infertility of the resulting eggs, respectively. The calculated competitiveness values for the 4 ratios were 0.55, 0.52, 0.42 and 0.88, respectively. Thus I males were only competitive at the highest flooding ration (15:1:1)

Biological basis of the sterile insect technique

International Nuclear Information System (INIS)

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

2005-01-01

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

Sterilization of melon flies: mating competitiveness after treatment with tepa or gamma irradiation and ratios of treated to untreated flies producing population suppression

International Nuclear Information System (INIS)

Ashraf, M.; Keiser, I.; Harris, E.J.

1976-01-01

Male melon flies, Dacus cucurbitae Coquillett, treated with a single dose of the chemosterilant tepa (tris(l-aziridinyl) phosphine oxide), or with gamma irradiation, either single or fractionated doses, did not differ significantly in sexual competitiveness as determined by percentage hatch of eggs. Mating competitiveness of males treated by either method ranged from 53 to 66 percent of that of untreated males. In another study, melon flies (males and females) sterilized with 0.0125 percent tepa, the threshold dose for both sexes, completely suppressed a population when the ratio was 16:16:1:1 (sterile males-sterile females-untreated males-untreated females) as determined by no egg hatch

Speciation and reduced hybrid female fertility in house mice.

Science.gov (United States)

Suzuki, Taichi A; Nachman, Michael W

2015-09-01

In mammals, intrinsic postzygotic isolation has been well studied in males but has been less studied in females, despite the fact that female gametogenesis and pregnancy provide arenas for hybrid sterility or inviability that are absent in males. Here, we asked whether inviability or sterility is observed in female hybrids of Mus musculus domesticus and M. m. musculus, taxa which hybridize in nature and for which male sterility has been well characterized. We looked for parent-of-origin growth phenotypes by measuring adult body weights in F1 hybrids. We evaluated hybrid female fertility by crossing F1 females to a tester male and comparing multiple reproductive parameters between intrasubspecific controls and intersubspecific hybrids. Hybrid females showed no evidence of parent-of-origin overgrowth or undergrowth, providing no evidence for reduced viability. However, hybrid females had smaller litter sizes, reduced embryo survival, fewer ovulations, and fewer small follicles relative to controls. Significant variation in reproductive parameters was seen among different hybrid genotypes, suggesting that hybrid incompatibilities are polymorphic within subspecies. Differences in reproductive phenotypes in reciprocal genotypes were observed and are consistent with cyto-nuclear incompatibilities or incompatibilities involving genomic imprinting. These findings highlight the potential importance of reduced hybrid female fertility in the early stages of speciation. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

Radiobiology of Small Hive Beetle (Coleoptera: Nitidulidae) and Prospects for Management Using Sterile Insect Releases.

Science.gov (United States)

Downey, Danielle; Chun, Stacey; Follett, Peter

2015-06-01

Small hive beetle, Aethina tumida Murray (Coleoptera: Nitidulidae), is considered a serious threat to beekeeping in the Western Hemisphere, Australia, and Europe mainly due to larval feeding on honey, pollen, and brood of the European honeybee, Apis mellifera L. Control methods are limited for this pest. Studies were conducted to provide information on the radiobiology of small hive beetle and determine the potential for sterile insect releases as a control strategy. Adult males and females were equally sensitive to a radiation dose of 80 Gy and died within 5-7 d after treatment. In reciprocal crossing studies, irradiation of females only lowered reproduction to a greater extent than irradiation of males only. For matings between unirradiated males and irradiated females, mean reproduction was reduced by >99% at 45 and 60 Gy compared with controls, and no larvae were produced at 75 Gy. Irradiation of prereproductive adults of both sexes at 45 Gy under low oxygen (1-4%) caused a high level of sterility (>99%) while maintaining moderate survivorship for several weeks, and should suffice for sterile insect releases. Sterile insect technique holds potential for suppressing small hive beetle populations in newly invaded areas and limiting its spread. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

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

Energy Technology Data Exchange (ETDEWEB)

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

1968-06-15

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

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'

Transcervical Sterilization: A Comparison of Essure® Permanent Birth Control System and Adiana® Permanent Contraception System

Science.gov (United States)

Palmer, Sophia N; Greenberg, James A

2009-01-01

Transcervical sterilization has moved female sterilization from a minimally invasive laparoscopic technique, which requires entry into the abdominal cavity, to a less invasive hysteroscopic procedure. Along with the decreased potential for complications, its ease of performance with minimal anesthesia has facilitated a move from the operating room to the office. This review compares the available data on transcervical sterilization procedures to better understand the strengths and weakness of each system. PMID:19609402

The effect of gamma radiation on sterility and mating ability of brown planthopper, Nilaparvata lugens(Stål) in field cage

Science.gov (United States)

Limohpasmanee, W.; Kongratarpon, T.; Tannarin, T.

2017-06-01

The brown planthopper, Nilaparvata lugens(Stål) is the major rice pest in Thailand. Adults and nymphs suck the sap from the rice plant causing it to wilt and transmitting the grassy stunt and the ragged stunt diseases. The population suppression by the sterile insect technique is overwhelmingly a function of mating between sterile males and wild females. The objectives of these experiments were to determine the suitable dose which induces partially sterile in N. lugens and their effect on wild population in the field cages. One-day-old 4th and 5th instar nymphs and adults were irradiated in a 60Co irradiator at the doses of 30, 60, 90 and 120 Gy. It was found that irradiation at the dose of 90 Gy induced complete sterility in female and 78.47 % sterility in males. The inherited sterility were transferred to their progenies and induced 51.46 and 77.00 % sterility in F-1 males and females. The irradiation as the mention dose did not affect mating ability. The competitiveness index was increased when the ratio of irradiated males per normal male was increased. The releasing irradiated males at 10 fold of normal males in field cages could suppress F-1 population 80.11 % and suppress F-2 population 80.32 % when compare with the control. This technique may be applied to delay and/or reduce seasonal increase of brown planthopper.

Population suppression in support of the sterile insect technique

International Nuclear Information System (INIS)

Mangan, R.L.

2005-01-01

Suppression or eradication of insect pest populations by the release of sterile insects is often dependent on supplementary methods of pest reduction to levels where the target pest population can be overflooded with sterile insects. Population suppression activities take place in advance of, or coincide with, the production of sterile insects. Supplementary methods to remove breeding opportunities, or management methods that prevent access of pests to the hosts, may reduce the population or prevent damage. Insecticides have been used widely in direct applications or applied as baits, in traps, or on specific sites where the pest makes contact or reproduces. As sterile insect release does not kill the pest, adult biting pests or fertile mated females of the pests will continue to attack hosts after the release of sterile insects. Thus supplementary pest suppression programmes and quarantine measures are essential to prevent damage or the spread of disease. Eradication or effective pest management requires that the entire population of the pest be treated, or that the programme apply immigration barriers. When supplementary pest control activities benefit the human population in areas being treated, such as in mosquito or screwworm eradication programmes, these activities are usually acceptable to the public, but when the public receives no direct benefit from supplementary control activities such as in fruit fly programmes, social resistance may develop. (author)

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

Mortality and sterility induced in Piophila casei by x-ray and neutron irradiation

Energy Technology Data Exchange (ETDEWEB)

Sacchi, L; Gasperi, G [Pavia Univ. (Italy). Ist. di Zoologia; Grigolo, A [Bari Univ. (Italy). Ist. di Zoologia e Anatomia Comparata; Caprotti, M [Pavia Univ. (Italy). Fondazio Clinica del Lavoro. Reparto di Radiologia; Pinelli, T; Altieri, S [Pavia Univ. (Italy). Istituto di Fisica Nucleare

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.

Effect of Gamma Radiation on Sterility , Sexual Competitiveness and Mating Ability of Carob Moth Ephestia calidella (Guen.) Irradiated as Pupae

International Nuclear Information System (INIS)

Ahmad, T.R.; Hamad, B.S.; Barkhi, G.S.

2007-01-01

When mature pupae (2 days before eclosion) of Ephestia calidella (Guen.) were irradiated with the doses of 0, 100, 200, 300 and 400 Gy, the males had a high level of sterility which was 92% at 300 Gy, but it was not significantly different from those treated with 200 and 400 Gy respectively.Furthermore,a high level of sterility (100%) was obtained for female pupae treated with 400 Gy.Meanwhile, when both males and females irradiated as pupae (2 days before eclosion) with 200, 300 and 400 Gy showed a high level of sterility which was 94.4, 98.2 and 99.6%, respectively.It is evident that females were less radio-resistant than males.When males from irradiated pupae at different doses added to untreated adult at ratio of (3:1:1) irradiated males :unirradiated males: unirradiated females the percentage og egg hatch decreased from 76.4% in the control to 36.3% at the dose of 400 Gy.However, sexual competitiveness value and inseminate female irradiated as pupae reduced with increasing doses

Studies on the ecology of insects sterilized artificially (gamma radiation), 8. Experimental analysis of the sexual competitiveness between normal males of the oriental fruit fly and males sterilized by the /sup 137/Cs gamma radiation

Energy Technology Data Exchange (ETDEWEB)

Kiyoku, M; Tsukuda, R [Okayama Univ. (Japan). Faculty of Agriculture

1974-09-01

Gamma-ray irradiation of 7 KR from /sup 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..gamma.. x N/sup -/, N..gamma.. x S/sup -/ and S..gamma.. x S/sup -/. 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..gamma.. and N..gamma.. has been examined in experiments of S..gamma.. x N..gamma.. x N/sup -/. (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..gamma../N..gamma.. (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..gamma../N..gamma.., showed in three convex curves under three degrees of competitiveness (0.265, 0.576 and 1.001). When both the values of S..gamma../N..gamma.. in the mating experiments and the sterility percentages are given, it is possible to obtain degrees of competitiveness using the curves.

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

Current status of backcross sterility in Heliothis virescens (F.)

International Nuclear Information System (INIS)

Hardee, D.D.; Laster, M.L.

1996-01-01

Because of insecticide resistance, high cost of controls and the need to reduce pesticide use, attempts have been made to manage Heliothis virescens with non-insecticidal techniques. One such approach has been the use of sterile male interspecific hybrids produced from crosses between males of H. virescens and females of H. subflexa

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.

Study of sexual functioning and disorder in women before and after tubal sterilization (tubectomy)

OpenAIRE

Kunkeri, Shweta Patil; Sathyanarayana Rao, T. S.; Andrade, Chittaranjan

2017-01-01

Introduction: Sexual relationship is a basis for mental health and continuity of the healthy generation. There are very few studies on the female sexual functioning, especially in India. Sterilization being the most common contraceptive method, sexual functioning in women undergoing this surgical intervention has not been adequately explored. Available studies have found conflicting results; some have reported that sterilization has positive effects on sexual functioning since anxiety of gett...

The sterilizing effect of pyriproxyfen on the malaria vector Anopheles gambiae: physiological impact on ovaries development.

Science.gov (United States)

Koama, Bayili; Namountougou, Moussa; Sanou, Roger; Ndo, Sévérin; Ouattara, Abdoulaye; Dabiré, Roch K; Malone, David; Diabaté, Abdoulaye

2015-03-04

Adult females An. gambiae were exposed in 3 min cone test to treated nets with PPF before or after they were blood fed. The effects of PPF on ovaries development, females oviposition and eggs hatching were assessed. Both unfed and fed mosquitoes exposed to PPF exhibited nearly complete inhibition of fecundity (70-100%) and fertility (90-100%). After females have been exposed once to PPF, the sterilizing effect on their fecundity was observed over 3 consecutive blood meals suggesting that PPF might have an irreversible sterilizing effect. Observation of the ovaries of exposed females to PPF under microscope revealed that the ovaries failed to develop even after several blood meals. The combination of PPF to pyrethroids on bednets could provide better malaria control tool and prevent the further development and spread of pyrethroid resistance in malaria vectors.

'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

Genetic basis to hybrid inviability is more complex than hybrid male sterility in Caenorhabditis nematodes.

Science.gov (United States)

Bundus, Joanna D; Wang, Donglin; Cutter, Asher D

2018-04-07

Hybrid male sterility often evolves before female sterility or inviability of hybrids, implying that the accumulation of divergence between separated lineages should lead hybrid male sterility to have a more polygenic basis. However, experimental evidence is mixed. Here, we use the nematodes Caenorhabditis remanei and C. latens to characterize the underlying genetic basis of asymmetric hybrid male sterility and hybrid inviability. We demonstrate that hybrid male sterility is consistent with a simple genetic basis, involving a single X-autosome incompatibility. We also show that hybrid inviability involves more genomic compartments, involving diverse nuclear-nuclear incompatibilities, a mito-nuclear incompatibility, and maternal effects. These findings demonstrate that male sensitivity to genetic perturbation may be genetically simple compared to hybrid inviability in Caenorhabditis and motivates tests of generality for the genetic architecture of hybrid incompatibility across the breadth of phylogeny.

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

International Nuclear Information System (INIS)

Sutrisno, Singgih

1986-01-01

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

Hybrid Sterility in Rice (Oryza sativa L.) Involves the Tetratricopeptide Repeat Domain Containing Protein.

Science.gov (United States)

Yu, Yang; Zhao, Zhigang; Shi, Yanrong; Tian, Hua; Liu, Linglong; Bian, Xiaofeng; Xu, Yang; Zheng, Xiaoming; Gan, Lu; Shen, Yumin; Wang, Chaolong; Yu, Xiaowen; Wang, Chunming; Zhang, Xin; Guo, Xiuping; Wang, Jiulin; Ikehashi, Hiroshi; Jiang, Ling; Wan, Jianmin

2016-07-01

Intersubspecific hybrid sterility is a common form of reproductive isolation in rice (Oryza sativa L.), which significantly hampers the utilization of heterosis between indica and japonica varieties. Here, we elucidated the mechanism of S7, which specially causes Aus-japonica/indica hybrid female sterility, through cytological and genetic analysis, map-based cloning, and transformation experiments. Abnormal positioning of polar nuclei and smaller embryo sac were observed in F1 compared with male and female parents. Female gametes carrying S7(cp) and S7(i) were aborted in S7(ai)/S7(cp) and S7(ai)/S7(i), respectively, whereas they were normal in both N22 and Dular possessing a neutral allele, S7(n) S7 was fine mapped to a 139-kb region in the centromere region on chromosome 7, where the recombination was remarkably suppressed due to aggregation of retrotransposons. Among 16 putative open reading frames (ORFs) localized in the mapping region, ORF3 encoding a tetratricopeptide repeat domain containing protein was highly expressed in the pistil. Transformation experiments demonstrated that ORF3 is the candidate gene: downregulated expression of ORF3 restored spikelet fertility and eliminated absolutely preferential transmission of S7(ai) in heterozygote S7(ai)/S7(cp); sterility occurred in the transformants Cpslo17-S7(ai) Our results may provide implications for overcoming hybrid embryo sac sterility in intersubspecific hybrid rice and utilization of hybrid heterosis for cultivated rice improvement. Copyright © 2016 by the Genetics Society of America.

Status and potential of F1 sterility for control of European corn borer, Ostrinia nubilalis Hb

International Nuclear Information System (INIS)

Rosca, I.; Barbulescu, A.

1994-01-01

In certain lepidopterous insects partially gamma-ray-sterilized males mated with normal females produce progeny which are more sterile than their male parents. Inherited sterility has been observed in numerous pests including the European corn borer, Ostrinia nubilalis Hb. The most important discoveries contributing the development of this techniques are reviewed. The studies on the European corn borer have revealed a dramatic inherited sterility effect when pupae have been irradiated with a low dose of 100 or 150 Gy. Data on the growth, development and behaviour of F 1 individuals indicate that the treated insects are highly competitive with the normal insects. Field tests of the inherited sterility technique in isolated O. nubilalis infestations have indicated that this method is effective and a small eradication has been done. These studies are continuing. (author)

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)

Radiation sterilization of livestock feeds

International Nuclear Information System (INIS)

Kawashima, Koji

1984-01-01

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

Housefly Larva Vermicomposting Efficiently Attenuates Antibiotic Resistance Genes in Swine Manure, with Concomitant Bacterial Population Changes.

Science.gov (United States)

Wang, Hang; Li, Hongyi; Gilbert, Jack A; Li, Haibo; Wu, Longhua; Liu, Meng; Wang, Liling; Zhou, Qiansheng; Yuan, Junxiang; Zhang, Zhijian

2015-11-01

Manure from swine treated with antimicrobials as feed additives is a major source for the expansion of the antibiotic resistance gene (ARG) reservoir in the environment. Vermicomposting via housefly larvae (Musca domestica) can be efficiently used to treat manure and regenerate biofertilizer, but few studies have investigated its effect on ARG attenuation. Here, we tracked the abundances of 9 ARGs and the composition and structure of the bacterial communities in manure samples across 6 days of full-scale manure vermicomposting. On day 6, the abundances of genes encoding tetracycline resistance [tet(M), tet(O), tet(Q), and tet(W)] were reduced (P biofertilizer in agroecosystems. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Anatomic Study of Female Sterility of Pinus tabulaeformis Carr.

Institute of Scientific and Technical Information of China (English)

Cheng Pengjun; Li Fenglan; Zheng Caixia

2003-01-01

The anatomic research on the mutant clone of Pinus tabulaeformis Carr. in the seed orchard in Xingcheng, LiaoningProvince was carried out. The female cone of the mutant clone looked like normal, but its ovules degenerated in the early stage. Thispaper tries to find out the reason and time of ovule abortion. It seems that the ovule abortion is probably caused by female sterilitybecause the microspores of this mutant clone were normal. Through the serial observations on the one-year-old macrosporangiatesand the ovules of two-year-old female cones of mutant and normal clone, it is found that the reason of ovule abortion in mutant cloneis the failure of the mitosis of free nuclei in the female gametophyte, and the time is about in the early April.

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

International Nuclear Information System (INIS)

Dimundu Puena, I.; Cirio, Ugo.

1978-01-01

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

[Essure--a novel method of sterilization].

Science.gov (United States)

Revel, Ariel; Nadjary, Michel; Shushan, Asher

2008-02-01

Essure hysteroscopic sterilization is a minimally invasive, outpatient approach to female sterilization, which avoids the possible complications of laparoscopic sterilization. This procedure has been available since 2003 in both Europe and North America. We present our experience of the first 12 cases of the procedure performed in Israel. Women who have completed their family planning were offered to consider Essure as their permanent contraception. The procedure was performed without anesthesia by the vaginoscopic technique at the hospital's outpatient clinic. Patients completed a questionnaire and were discharged immediately following the procedure. A follow-up checkup was completed after three months including three dimensional sonography, abdominal X-ray and occasional hysterosalpingogram. Twelve patients participated in the pilot group at Hadassah. The average age was 40 years (34-45) and the average number of children was 5 (4-8). The average time for the procedure was under 8 minutes. Periostial adhesions required adhesiolysis prior to insertion of the device in one patient. All patients resumed their normal activity on the same day. Our patient satisfaction survey revealed that the procedure was associated with high satisfaction levels. Sonographic and radiographic studies confirmed the good placement of the device. The Essure procedure was well tolerated by patients. The limitation is probably going to be the price of Essure, as this procedure is not covered by the 'health basket' in Israel.

Gamma radiation effects on mating behavior, inherited sterility, and competitiveness of Cadra cautella (Walker) (Lepidoptera:Pyralidae)

International Nuclear Information System (INIS)

Amoako-Atta, B.

1976-01-01

Mating efficiency of male Cadra cautella is restricted to within 72 hr of pose-eclosion. Gamma radiation of 8-day pupae did not affect the mating frequency of males in constant association with females for 72 hrs. When association was delayed for 1--7 days, there was progressive decrease in mating efficiency. The decline was related to reduced sperm viability. Increasing the dose accentuated the reduction in reproductive potential. Reproductive behavior of generation lines (F 1 --F 5 ) between irradiated males and normal females was studied. The sex ratio was distorted (more males) primarily in the F 1 and F 2 generations; the reproductive rate was lower in these early generations. When reproductive rate increased, the sex ratio was not distorted. A partially sterilizing dose of 20 krad to P 1 males induced complete inherited sterility in the progeny; the population of F 1 --F 2 collapsed. The ratio of sterile to fertile males needed to reduce reproductive nonirradiated females to 0 in the laboratory was studied. Release ratios of sterile males (S) : normal males (M) : fertile virgin females (N) varied from 0--20 S:M:N respectively. Population increases from various release ratios were lowered in each successive release ratio. The 20 S reduced the mean population increase of 2N from the expected 300-fold (as in the controls 0S:2M:2N) to only 4-fold. In that 20S:2M:2N release ratio, only 15% of the cultures produced any measurable F 1 progeny (average = 4F 1 progeny/culture) whereas the remaining 85% of the cultures did not produce any F 1 progeny. All control cultures were productive

Laboratory and field evaluation of sterile male boll weevil competitiveness

International Nuclear Information System (INIS)

McGovern, W.L.

1976-01-01

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

Combined effects of a chemical mutagen and radiation sterilized diet in mutagenicity and reproduction studies in the same mouse

International Nuclear Information System (INIS)

Renner, H.W.

1975-01-01

The possible intensification of the mutagenic effect of cyclophosphamide (Endoxan) by the feeding of a radiation-sterilized diet (dose, 4.5 Mrad) was studied in 2000 NMRI/Han mice. In a dominant lethal test, males were pretreated with 100 mg Endoxan/kg body weight. The greatest sensitivity towards Endoxan was observed during the late-spermatid stage. No significant differences were detected between the control group (Endoxan plus non-irradiated diet) and the experimental group (Endoxan plus radiation-sterilized diet). In this test, radiation-sterilized feed showed no co-mutagenic effect when combined with Endoxan treatment. In a reproduction study of 7 months duration (continuous mating without lactation periods), the females were treated every 2 wk with 20 mg Endoxan/kg body weight. The decline in litter size with increasing number of litters (i.e. with advancing age of the females) was more pronounced after treatment with the chemical mutagen than in the untreated group. Increases in the frequency of abortions and in premature sterility resulted from Endoxan treatment. During the entire observation period, no effects from the intake of radiation-sterilized food were detected. (author)

Induction of inherited sterility and sex ratio distribution due to exposure to substerilising doses of gamma radiation in cotton bollworm Earias vittella fabricius

International Nuclear Information System (INIS)

Tamhankar, A.J.; Shantharam, K.

2005-01-01

Substerilising doses of gamma radiation induced inherited sterility and sex ratio distortion in the cotton bollworm Earias vittella fabricius. Adults irradiated with 75 Gy and self-crossed, provided sterile F 1 adults, suitable for direct use in sterile insect technique (SIT). In case of 50 Gy, the F 1 adults, when backcrossed, produced F 2 progeny with sex ratio in favour of females (1: >3). With 25 Gy, a sex ratio distortion was recorded in F 1 (1 male: 2.25 females) and self-crossing of F 1 resulted in progeny with a sex ratio of 3:1. Backcrossing of the F 1 female produced F 2 progeny with a sex ratio of 1:5. These results have implications in improving cost/benefit ratio of SIT for this species. (author)

[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.

Transient population dynamics of mosquitoes during sterile male releases: modelling mating behaviour and perturbations of life history parameters.

Directory of Open Access Journals (Sweden)

Christopher M Stone

Full Text Available The release of genetically-modified or sterile male mosquitoes offers a promising form of mosquito-transmitted pathogen control, but the insights derived from our understanding of male mosquito behaviour have not fully been incorporated into the design of such genetic control or sterile-male release methods. The importance of aspects of male life history and mating behaviour for sterile-male release programmes were investigated by projecting a stage-structured matrix model over time. An elasticity analysis of transient dynamics during sterile-male releases was performed to provide insight on which vector control methods are likely to be most synergistic. The results suggest that high mating competitiveness and mortality costs of released males are required before the sterile-release method becomes ineffective. Additionally, if released males suffer a mortality cost, older males should be released due to their increased mating capacity. If released males are of a homogenous size and size-assortative mating occurs in nature, this can lead to an increase in the abundance of large females and reduce the efficacy of the population-suppression effort. At a high level of size-assortative mating, the disease transmission potential of the vector population increases due to male releases, arguing for the release of a heterogeneously-sized male population. The female population was most sensitive to perturbations of density-dependent components of larval mortality and female survivorship and fecundity. These findings suggest source reduction might be a particularly effective complement to mosquito control based on the sterile insect technique (SIT. In order for SIT to realize its potential as a key component of an integrated vector-management strategy to control mosquito-transmitted pathogens, programme design of sterile-male release programmes must account for the ecology, behaviour and life history of mosquitoes. The model used here takes a step in this

Study on stable fly eradication by sterile-male technique. Effects of X-ray irradiation on the stable fly

Energy Technology Data Exchange (ETDEWEB)

Chung, K H; Ryu, J; Kwon, S H [Korea Atomic Energy Research Inst., Seoul (Republic of Korea)

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.

Sterilization of fruit flies (Diptera: Tephritidae) with X-rays for sterile insect technique programs; Esterilizacao de moscas-das-frutas (Diptera: Tephritidae) com raios-X para programas de tecnica do inseto esteril

Energy Technology Data Exchange (ETDEWEB)

Mastrangelo, Thiago de Araujo

2009-07-01

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 {gamma} radiation from {sup 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 {gamma} rays (thus, a RBE{approx}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 {gamma} rays decreased in 99% comparing with the control group (RBE{approx}1.5). 99% sterility of A. fraterculus irradiated females was achieved with 60-80 Gy (RBE{approx}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{approx}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 {gamma} 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

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

Science.gov (United States)

Mao, Jialin; Pfeifer, Samantha; Schlegel, Peter

2015-01-01

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

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.

Radiation sterilization of medical products

International Nuclear Information System (INIS)

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

1989-01-01

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

A novel male sterility-fertility restoration system in plants for hybrid seed production.

Science.gov (United States)

Singh, Surendra Pratap; Singh, Sudhir P; Pandey, Tripti; Singh, Ram Rakshpal; Sawant, Samir V

2015-06-15

Hybrid seeds are used for stimulated crop production, as they harness heterosis. The achievement of complete male-sterility in the female-parent and the restored-fertility in F1-hybrids are the major bottlenecks in the commercial hybrid seed production. Here, we report a male sterility-fertility restoration system by engineering the in most nutritive anther wall layer tapetum of female and male parents. In the female parent, high-level, and stringent expression of Arabidopsis autophagy-related gene BECLIN1 was achieved in the tapetum, which altered the tapetal degeneration program, leading to male sterility. This works on our previously demonstrated expression cassette based on functional complementation of TATA-box mutant (TGTA) promoter and TATA-binding protein mutant3 (TBPm3), with modification by conjugating Long Hypocotyle in Far-Red1 fragment (HFR1(NT131)) with TBPm3 (HFR1(NT131)-TBPm3) to exercise regulatory control over it. In the male parent, tapetum-specific Constitutive photo-morphogenesis1 (COP1) was expressed. The F1 obtained by crossing these engineered parents showed decreased BECLIN1 expression, which was further completely abolished when COP1-mutant (COP1(L105A)) was used as a male parent, leading to normal tapetal development and restored fertility. The system works on COP1-HFR1 interaction and COP1-mediated degradation of TBPm3 pool (HFR1(NT131)-TBPm3). The system can be deployed for hybrid seed production in agricultural crops.

A general method for identifying major hybrid male sterility genes in Drosophila.

Science.gov (United States)

Zeng, L W; Singh, R S

1995-10-01

The genes responsible for hybrid male sterility in species crosses are usually identified by introgressing chromosome segments, monitored by visible markers, between closely related species by continuous backcrosses. This commonly used method, however, suffers from two problems. First, it relies on the availability of markers to monitor the introgressed regions and so the portion of the genome examined is limited to the marked regions. Secondly, the introgressed regions are usually large and it is impossible to tell if the effects of the introgressed regions are the result of single (or few) major genes or many minor genes (polygenes). Here we introduce a simple and general method for identifying putative major hybrid male sterility genes which is free of these problems. In this method, the actual hybrid male sterility genes (rather than markers), or tightly linked gene complexes with large effects, are selectively introgressed from one species into the background of another species by repeated backcrosses. This is performed by selectively backcrossing heterozygous (for hybrid male sterility gene or genes) females producing fertile and sterile sons in roughly equal proportions to males of either parental species. As no marker gene is required for this procedure, this method can be used with any species pairs that produce unisexual sterility. With the application of this method, a small X chromosome region of Drosophila mauritiana which produces complete hybrid male sterility (aspermic testes) in the background of D. simulans was identified. Recombination analysis reveals that this region contains a second major hybrid male sterility gene linked to the forked locus located at either 62.7 +/- 0.66 map units or at the centromere region of the X chromosome of D. mauritiana.

Dominance of sterilization and alternative choices of contraception in India: An appraisal of the socioeconomic impact

OpenAIRE

Oliveira, I.; Dias, J. G.; Padmadas, S. S.

2014-01-01

WOS:000330510000069 (Nº de Acesso Web of Science) Background: The recent decline in fertility in India has been unprecedented especially in southern India, where fertility is almost exclusively controlled by means of permanent contraceptive methods, mainly female sterilization, which constitutes about two-thirds of overall contraceptive use. Many Indian women undergo sterilization at relatively young ages as a consequence of early marriage and childbearing in short birth intervals. This re...

Biological and Histological Studies of Inherited Sterility on Irradiated Males of the Potato Tuber Moth Phthorimaea operculella (Zeller)

International Nuclear Information System (INIS)

Abdel-Kawy, F.K; Ghally, S.E.; Abd-Alla, M.S; Mohamed, S.A.

2005-01-01

In this study, gamma radiation was applied at sub sterilizing doses, 100, 150 and 200 Gy for full grown pupae of male Ph. operculella. Sterility, reproduction, mortality, and histological effects on the testis were investigated. The percent mating was not affected to any dosage except at (To x N+) in the parents at 200 Gy and in the progeny with 150 Gy. The number of spermatophores per mated female for parents and progeny was not obviously different from the control. The percent sperm transfer for both normal and irradiated males was not affected. The average number of eggs per female significantly reduced when when mated with parental males irradiated with 200 Gy. Fecundity of female progeny was negatively correlated with the dose received by parental males. The amount of inherited sterility of progeny was dependent on the dosage received by the male parent. Irradiation had not effect on male and female longevity for parents and their progeny, however the sex ratio was in favour of males in the resulting progenies. Gamma radiation had effect on emergency of parental males more than their progeny. The size and structure of testis contents were severely affected with increase the dosage from 150 to 200 Gy and the effects were more pronounced in the progeny than the parental adults

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

International Nuclear Information System (INIS)

Ahmed, H.

2015-01-01

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

Radiosterilization and gas sterilization

International Nuclear Information System (INIS)

Schultz, H.A.; Gruenewald, T.

1987-01-01

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

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

International Nuclear Information System (INIS)

2006-01-01

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

Retrospective cost analysis comparing Essure hysteroscopic sterilization and laparoscopic bilateral tubal coagulation.

Science.gov (United States)

Hopkins, Matthew R; Creedon, Douglas J; Wagie, Amy E; Williams, Arthur R; Famuyide, Abimbola O

2007-01-01

To compare the institutional cost of permanent female sterilization by Essure hysteroscopic sterilization and laparoscopic bilateral coagulation. Retrospective cohort study (Canadian Task Force classification II-2). Midwestern academic medical center. Women of reproductive age who elected for permanent contraception by the Essure method (n = 43) or by laparoscopic tubal coagulation (n = 44) during the time frame studied. Placement of the Essure inserts according to the manufacturer's instructions or laparoscopic tubal sterilization using bipolar forceps according to standard techniques of open or closed laparoscopy. Cost-center data for the institutional cost of the procedure was abstracted for each patient included in the study. In addition, demographic data and procedural information were obtained and compared for the patient populations. The Essure system of hysteroscopic sterilization had a significantly decreased cost compared with laparoscopic tubal sterilization when both procedures were performed in an operating room setting. The decrease per patient in institutional cost was 180 dollars (p = .038). This included the cost of the confirmatory hysterosalpingogram 3 months after Essure placement and the cost of laparoscopic tubal occlusion by Filshie clip if the Essure micro-inserts could not be placed. The majority of the cost was related to hospital costs as opposed to physician costs. The Essure procedure had higher costs for disposable equipment (p Essure hysteroscopic sterilization had significant cost savings compared with laparoscopic tubal sterilization (p = .038). We believe that our data represent the minimum of potential savings using this approach, and future developments will only increase the cost difference found in our study.

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

International Nuclear Information System (INIS)

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

2007-01-01

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

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

A syndrome of multiorgan hyperplasia with features of gigantism, tumorigenesis, and female sterility in p27(Kip1)-deficient mice.

Science.gov (United States)

Fero, M L; Rivkin, M; Tasch, M; Porter, P; Carow, C E; Firpo, E; Polyak, K; Tsai, L H; Broudy, V; Perlmutter, R M; Kaushansky, K; Roberts, J M

1996-05-31

Targeted disruption of the murine p27(Kip1) gene caused a gene dose-dependent increase in animal size without other gross morphologic abnormalities. All tissues were enlarged and contained more cells, although endocrine abnormalities were not evident. Thymic hyperplasia was associated with increased T lymphocyte proliferation, and T cells showed enhanced IL-2 responsiveness in vitro. Thus, p27 deficiency may cause a cell-autonomous defect resulting in enhanced proliferation in response to mitogens. In the spleen, the absence of p27 selectively enhanced proliferation of hematopoietic progenitor cells. p27 deletion, like deletion of the Rb gene, uniquely caused neoplastic growth of the pituitary pars intermedia, suggesting that p27 and Rb function in the same regulatory pathway. The absence of p27 also caused an ovulatory defect and female sterility. Maturation of secondary ovarian follicles into corpora lutea, which express high levels of p27, was markedly impaired.

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)

Investigating the potential of selected natural compounds to increase the potency of pyrethrum against houseflies Musca domestica (Diptera: Muscidae)

DEFF Research Database (Denmark)

Joffe, Tanya; Gunning, Robin V; Allen, Geoff R

2012-01-01

oil, grapefruit oil and parsley seed oil, with 59, 50 and 41% mortality respectively, compared with 18% mortality with unsynergised pyrethrum. Against 381zb houseflies, the most effective natural synergists were parsley seed oil and dillapiole oil. Esterase inhibition by the natural compounds and PBO...... in vitro showed no correlation with pyrethrum synergism in vivo, whereas the inhibition of oxidases in vitro more closely correlated with pyrethrum synergism in vivo. CONCLUSION: Dillapiole oil and parsley seed oil showed the greatest potential as pyrethrum synergists. PBO remained the most effective...

Sterilization of DACUS CUCUMIS FRENCH (DIPTERA: TEPHRITDAE) by gamma radiation

International Nuclear Information System (INIS)

Hooper, G.H.S.

1976-01-01

When newly emerged adult Dacus cucumis French were irradiated in nitrogen, following a 15 min exposure to an atmosphere of pure nitrogen, the degree of sterility induced by a given dose was less than that obtained with the same dose in air. To achieve sterility in males of approximately 98 per cent doses of 7 krad in air and 13 krad in nitrogen were required. With females, total sterility through infecundity was achieved by 6 krad in air and 13 krad in nitrogen. Based on the hatch of eggs from competitive mating tests, males receiving 14 krad in nitrogen were significantly more competitive than males given 9 krad in air. The optimal light intensity for mating of D. cucumis under artificial conditions was 16.2, 1x. With this light intensity the mating propensity of males irradiated with 9 and 11 krad in air was significantly less than that of untreated males. The mating propensity of males given 14 krad in nitrogen approximated that of untreated males. (author)

The sterile-male-release technique in Great Lakes sea lamprey management

Science.gov (United States)

Twohey, Michael B.; Heinrich, John W.; Seelye, James G.; Fredricks, Kim T.; Bergstedt, Roger A.; Kaye, Cheryl A.; Scholefield, Ron J.; McDonald, Rodney B.; Christie, Gavin C.

2003-01-01

The implementation of a sterile-male-release technique from 1991 through 1999 and evaluation of its effectiveness in the Great Lakes sea lamprey (Petromyzon marinus) management program is reviewed. Male sea lampreys were injected with the chemosterilant bisazir (P,P-bis(1-aziridinyl)-N-methylphosphinothioic amide) using a robotic device. Quality assurance testing indicated the device delivered a consistent and effective dose of bisazir. Viability of embryos in an untreated control group was 64% compared to 1% in a treatment group. A task force developed nine hypotheses to guide implementation and evaluation of the technique. An annual average of 26,000 male sea lampreys was harvested from as many as 17 Great Lakes tributaries for use in the technique. An annual average of 16,100 sterilized males was released into 33 tributaries of Lake Superior to achieve a theoretical 59% reduction in larval production during 1991 to 1996. The average number of sterile males released in the St. Marys River increased from 4,000 during 1991 to 1996 to 20,100 during 1997 to 1999. The theoretical reduc-stertion in reproduction when combined with trapping was 57% during 1991 to 1996 and 86% during 1997 to 1999. Evaluation studies demonstrated that sterilized males were competitive and reduced production of larvae in streams. Field studies and simulation models suggest reductions in reproduction will result in fewer recruits, but there is risk of periodic high recruitment events independent of sterile-male release. Strategies to reduce reproduction will be most reliable when low densities of reproducing females are achieved. Expansion of the technique is limited by access to additional males for sterilization. Sterile-male release and other alternative controls are important in delivering integrated pest management and in reducing reliance on pesticides.

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

Field trials in South China to control the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae) using radiation-induced sterility

International Nuclear Information System (INIS)

Yang, R.; Xia, D.; Gu, W.; Zhang, Y.

2002-01-01

This paper discusses the control of the diamondback moth, Plutella xylostella by the sterile insect technique (SIT). Our studies included mating characteristics, sterility of the F 1 generation, dispersal and recapture of irradiated moths, as well as control of DBM using SIT and F 1 sterility, and an economic evaluation of F 1 sterility to protect cabbage. Male DBM mated an average of 16 times and female DBM mated an average of 4 times. However, irradiated male DBM only mated an average of 7.2 times. Seventy percent of matings occurred from 18:00-24:00 h with an average duration of 80 min. Irradiated male moths and untreated male moths exhibited the same attraction to female moths. After 10 days, most (94.2%) of the released, sterile DBM were recaptured within 40 m of the release site. Only one DBM was recaptured at 120 m from the release site. The area of dispersal was calculated to be 696 m 2 during the first three days. In a field study to control DBM by releases of irradiated insects, the ratio of sterile to wild DBM was 4.7:1. During this study, the egg sterility in the F 1 and F 2 generations was 79.0% and 81.7%, respectively. The developmental times for the F 1 and F 2 generations were 4 and 12 days longer, respectively, than for DBM in the control area. Thus, the number of DBM generations was reduced in the treated field. With successive releases over two generations, the control effectiveness was 80.8% in the F 1 generation and 79.1% in the F 2 generation. The cost of using F 1 sterility to control DBM in a small field was similar to the cost of using pesticides. Therefore, the use of F 1 sterility should be an economically viable control strategy for DBM that also would help protect the environment from the overuse of pesticides. (author)

Computer model for predicting the effect of inherited sterility on population growth

International Nuclear Information System (INIS)

Carpenter, J.E.; Layton, R.C.

1993-01-01

A Fortran based computer program was developed to facilitate modelling different inherited sterility data sets under various paradigms. The model was designed to allow variable input for several different parameters, such as rate of increase per generation, release ratio and initial population levels, reproductive rates and sex ratios resulting from different matings, and the number of nights a female is active in mating and oviposition. The model and computer program should be valuable tools for recognizing areas in which information is lacking and for identifying the effect that different parameters can have on the efficacy of the inherited sterility method. (author). 8 refs, 4 figs

The pachytene checkpoint and its relationship to evolutionary patterns of polyploidization and hybrid sterility.

Science.gov (United States)

Li, X C; Barringer, B C; Barbash, D A

2009-01-01

Sterility is a commonly observed phenotype in interspecific hybrids. Sterility may result from chromosomal or genic incompatibilities, and much progress has been made toward understanding the genetic basis of hybrid sterility in various taxa. The underlying mechanisms causing hybrid sterility, however, are less well known. The pachytene checkpoint is a meiotic surveillance system that many organisms use to detect aberrant meiotic products, in order to prevent the production of defective gametes. We suggest that activation of the pachytene checkpoint may be an important mechanism contributing to two types of hybrid sterility. First, the pachytene checkpoint may form the mechanistic basis of some gene-based hybrid sterility phenotypes. Second, the pachytene checkpoint may be an important mechanism that mediates chromosomal-based hybrid sterility phenotypes involving gametes with non-haploid (either non-reduced or aneuploid) chromosome sets. Studies in several species suggest that the strength of the pachytene checkpoint is sexually dimorphic, observations that warrant future investigation into whether such variation may contribute to differences in patterns of sterility between male and female interspecific hybrids. In addition, plants seem to lack the pachytene checkpoint, which correlates with increased production of unreduced gametes and a higher incidence of polyploid species in plants versus animals. Although the pachytene checkpoint occurs in many animals and in fungi, at least some of the genes that execute the pachytene checkpoint are different among organisms. This finding suggests that the penetrance of the pachytene checkpoint, and even its presence or absence can evolve rapidly. The surprising degree of evolutionary flexibility in this meiotic surveillance system may contribute to the observed variation in patterns of hybrid sterility and in rates of polyploidization.

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

Energy Technology Data Exchange (ETDEWEB)

Kratochvil, H [Department of Evolutionary Biology, University of Vienna, Halsriegelstr. 34, Vienna A-1090 (Austria); Noll, A [Institut fuer Schallforschung, Oe Ak d Wiss, Wohllebengasse 12-14, Vienna A-1040 (Austria); Bolldorf, J [Umweltbundesamt, Spittelauer Laende 5, Vienna A-1090 (Austria); Parker, A G [Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, FAO/IAEA Agriculture and Biotechnology Laboratory, Seibersdorf A-2444 (Austria)

2012-07-15

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)

No evidence for faster male hybrid sterility in population crosses of an intertidal copepod (Tigriopus californicus).

Science.gov (United States)

Willett, Christopher S

2008-06-01

Two different forces are thought to contribute to the rapid accumulation of hybrid male sterility that has been observed in many inter-specific crosses, namely the faster male and the dominance theories. For male heterogametic taxa, both faster male and dominance would work in the same direction to cause the rapid evolution of male sterility; however, for taxa lacking differentiated sex chromosomes only the faster male theory would explain the rapid evolution of male hybrid sterility. It is currently unknown what causes the faster evolution of male sterility, but increased sexual selection on males and the sensitivity of genes involved in male reproduction are two hypotheses that could explain the observation. Here, patterns of hybrid sterility in crosses of genetically divergent copepod populations are examined to test potential mechanisms of faster male evolution. The study species, Tigriopus californicus, lacks differentiated, hemizygous sex chromosomes and appears to have low levels of divergence caused by sexual selection acting upon males. Hybrid sterility does not accumulate more rapidly in males than females in these crosses suggesting that in this taxon male reproductive genes are not inherently more prone to disruption in hybrids.

Hybrid male sterility between Drosophila willistoni species is caused by male failure to transfer sperm during copulation.

Science.gov (United States)

Civetta, Alberto; Gaudreau, Chelsea

2015-05-01

The biological concept of species stresses the importance of understanding what mechanisms maintain species reproductively isolated from each other. Often such mechanisms are divided into premating and postmating, with the latest being the result of either prezygotic or postzygotic isolation barriers. Drosophila willistoni quechua and Drosophila willistoni willistoni are two subspecies that experience reproductive isolation. When a D. w. quechua female is crossed with a D. w. willistoni male, the hybrid males (F1QW) are unable to father progeny; however, the reciprocal cross produces fertile hybrids. Thus, the mechanism of isolation is unidirectional hybrid male sterility. However, the sterile F1QW males contain large amounts of motile sperm. Here we explore whether pre-copulatory or post-copulatory pre-zygotic mechanisms serve as major deterrents in the ability of F1QW males to father progeny. Comparisons of parental and hybrid males copulation durations showed no significant reduction in copulation duration of F1QW males. Interrupted copulations of the parental species confirmed that sperm transfer occurs before the minimum copulation duration registered for F1QW males. However, we found that when females mate with F1QW males, sperm is not present inside the female storage organs and that the lack of sperm in storage is due to failure to transfer sperm rather than spillage or active sperm dumping by females. Sterility of F1QW hybrid males is primarily driven by their inability to transfer sperm during copulation.

Management of long-term and reversible hysteroscopic sterilization: a novel device with nickel-titanium shape memory alloy

Science.gov (United States)

2014-01-01

Background Female sterilization is the second most commonly used method of contraception in the United States. Female sterilization can now be performed through laparoscopic, abdominal, or hysteroscopic approaches. The hysteroscopic sterilization may be a safer option than sterilization through laparoscopy or laparotomy because it avoids invading the abdominal cavity and undergoing general anaesthesia. Hysteroscopic sterilization mainly includes chemical agents and mechanical devices. Common issues related to the toxicity of the chemical agents used have raised concerns regarding this kind of contraception. The difficulty of the transcervical insertion of such mechanical devices into the fallopian tubes has increased the high incidence of device displacement or dislodgment. At present, Essure® is the only commercially available hysteroscopic sterilization device being used clinically. The system is irreversible and is not effective immediately. Presentation of the hypothesis Our new hysteroscopic sterility system consists of nickel-titanium (NiTi) shape memory alloy and a waterproof membrane. The NiTi alloy is covered with two coatings to avoid toxic Ni release and to prevent stimulation of epithelial tissue growth around the oviducts. Because of the shape memory effect of the NiTi alloy, the device works like an umbrella: it stays collapsed at low temperature before placement and opens by the force of shape memory activated by the body temperature after it is inserted hysteroscopically into the interstitial tubal lumen. The rim of the open device will incise into interstitial myometrium during the process of unfolding. Once the device is fixed, it blocks the tube completely. When the patient no longer wishes for sterilization, the device can be closed by perfusing liquid with low temperature into the uterine cavity, followed by prospective hysteroscopic removal. After the device removal, the fallopian tube will revert to its physiological functions. Testing the

Prospects of radiation sterilization of medical devices

International Nuclear Information System (INIS)

Hosobuchi, Kazunari

1992-01-01

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

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

Science.gov (United States)

Mann, A; Kiefer, M; Leuenberger, H

2001-03-01

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

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.

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.

Hybrid sterility in crosses between two Brazilian sibling species of the Anopheles albitarsis complex.

Science.gov (United States)

Fontoura, Nathalia Giglio; Araki, Alejandra Saori; Van Der Maas Azevedo, Renata; Galardo, Allan Kardec Ribeiro; Peixoto, Alexandre Afranio; Lima, José Bento Pereira

2014-12-04

Complexes of cryptic species are common in several taxa and this is also the case in the Anopheles genus, a group including all known human malaria vectors. The Anopheles albitarsis complex comprises at least nine cryptic species, some of which are implicated as vectors of human malaria. Several different types of data have been generated for this species complex such as cytogenetics, alloenzymes, morphological and feeding behavioral, hybridization experiments, RAPD-PCR and RFLP and mitochondrial and nuclear markers. Studies focused on its postzygotic isolation are still somewhat rare in the literature despite their importance to understand the speciation process and the level of gene flow potentially occurring among the different sibling species. Hybridization experiments between Anopheles albitarsis s.s. and Anopheles marajoara, as well as backcrosses between hybrids and Anopheles albitarsis s.s., were performed using the induced mating technique. Results were compared to intraspecific crosses. Larva-to-adult viability and sex ratio were also assessed. Male hybrids show very low insemination rates and nearly complete sterility, apparently due to abnormalities in their reproductive organs. Evidence of partial sterility among the hybrid females was also observed. Our data indicated that Anopheles albitarsis s.s. and Anopheles marajoara show a high level of postzygotic isolation with a strong hybrid male sterility. This result is consistent with the Haldane's rule which states that in interspecific crosses the heterogametic sex is the first to be affected. However, the fact that the females are not completely sterile raises the possibility of introgression between these two siblings species.

Production of a sterile species via active-sterile mixing: An exactly solvable model

Science.gov (United States)

Boyanovsky, D.

2007-11-01

The production of a sterile species via active-sterile mixing in a thermal medium is studied in an exactly solvable model. The exact time evolution of the sterile distribution function is determined by the dispersion relations and damping rates Γ1,2 for the quasiparticle modes. These depend on γ˜=Γaa/2ΔE, with Γaa the interaction rate of the active species in absence of mixing and ΔE the oscillation frequency in the medium without damping. γ˜≪1, γ˜≫1 describe the weak and strong damping limits, respectively. For γ˜≪1, Γ1=Γaacos⁡2θm; Γ2=Γaasin⁡2θm where θm is the mixing angle in the medium and the sterile distribution function does not obey a simple rate equation. For γ˜≫1, Γ1=Γaa and Γ2=Γaasin⁡22θm/4γ˜2, is the sterile production rate. In this regime sterile production is suppressed and the oscillation frequency vanishes at an Mikheyev-Smirnov-Wolfenstein (MSW) resonance, with a breakdown of adiabaticity. These are consequences of quantum Zeno suppression. For active neutrinos with standard model interactions the strong damping limit is only available near an MSW resonance if sin⁡2θ≪αw with θ the vacuum mixing angle. The full set of quantum kinetic equations for sterile production for arbitrary γ˜ are obtained from the quantum master equation. Cosmological resonant sterile neutrino production is quantum Zeno suppressed relieving potential uncertainties associated with the QCD phase transition.

Cost-effectiveness analysis comparing the essure tubal sterilization procedure and laparoscopic tubal sterilization.

Science.gov (United States)

Thiel, John A; Carson, George D

2008-07-01

To analyze the financial implications of establishing a hysteroscopic sterilization program using the Essure micro-insert tubal sterilization system in an ambulatory clinic. A retrospective cohort study (Canadian Task Force classification Type II-2), in an ambulatory women's health clinic in a tertiary hospital, of 108 women undergoing Essure coil insertion between 2005 and 2006, and 104 women undergoing laparoscopic tubal sterilization for permanent sterilization between 2001 and 2004. The Essure procedures used a 4 mm single channel operative hysteroscope and conscious sedation (fentanyl and midazolam); the laparoscopic tubal sterilizations were completed under general anaesthesia with a 7 mm laparoscope and either bipolar cautery or Filshie clips. Costs associated with the procedure, follow-up, and management of any complications (including nursing, hospital charges, equipment, and disposables) were tabulated. The Essure coils were successfully placed on the first attempt in 103 of 108 women (95%). Three patients required a second attempt to complete placement and two patients required laparoscopic tubal sterilization after an unsuccessful Essure. All 104 laparoscopic tubals were completed on the first attempt with no complications reported. The total cost for the 108 Essure procedures, including follow-up evaluation, was $138,996 or $1287 per case. The total cost associated with the 104 laparoscopic tubal sterilization procedures was $148,227 or $1398 per case. The incremental cost-effectiveness ratio was $111. The Essure procedure in an ambulatory setting resulted in a statistically significant cost saving of $111 per sterilization procedure. Carrying out the Essure procedure in an ambulatory setting frees space in the operating room for other types of cases, improving access to care for more patients.

Juvenile sterile granulomatous dermatitis (puppy strangle in Pekingese and German shepherd puppies

Directory of Open Access Journals (Sweden)

Mohammad Abbaszadeh Hasiri

2015-07-01

Full Text Available Juvenile sterile granulomatous dermatitis is an uncommon granulomatous and pustular disorder of the face, pinnae, and submandibular lymph nodes of puppies. A 10-week-old male Pekingese and a 8-week-old female German shepherd presented with submandibular lymphadenomegaly, skin lesions on muzzle and periocular area (Papules, crusts and pustules. The case did not respond to antibiotic therapy. Results of a hemogram, biochemical panel, and urinalysis were normal. Due to skin scraping, cytology examination (impression smear, fungal and bacterial culture and response to therapy puppy strangle (juvenile cellulitis was diagnosed. The puppies made a full recovery on glucocorticoid therapy. The present case report describes the first report of juvenile sterile granulomatous dermatitis in Iran.

Essure hysteroscopic sterilization versus interval laparoscopic bilateral tubal ligation: a comparative effectiveness review.

Science.gov (United States)

Ouzounelli, Myrsini; Reaven, Nancy L

2015-01-01

A comparative effectiveness analysis was performed to examine the risks and benefits of laparoscopic bilateral tubal ligation compared with hysteroscopic sterilization using the Essure Permanent Birth Control System (Bayer HealthCare AG, Whippany, NJ). Existing evidence shows that both LBTL and Essure are safe and effective methods of female sterilization. Both have high rates of efficacy and low rates of complications although when complications do occur, those related to the Essure procedure are more likely to be minor in nature. The analysis was limited by the restricted number of studies involving head-to-head comparisons of the 2 approaches. Copyright © 2015 AAGL. Published by Elsevier Inc. All rights reserved.

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.

Genetic and Cytogenetic Basis of Radiation-Induced Sterility in the Adult Male Cabbage Looper Trichoplusia Ni

Energy Technology Data Exchange (ETDEWEB)

North, D. T.; Holt, G. G. [Metabolism and Radiation Research Laboratory, Entomology Research Division, ARS, United States Department of Agriculture, Fargo, ND (United States)

1968-06-15

The relationship of egg hatch as a function of radiation dose is of a two-hit nature when irradiated adult males are mated to non-irradiated virgin females. Sterility as a function of dose is usually linear in insects. However, other species of moths respond similarly to irradiation, so it is indicative that the mechanism involved in producing sterility in Lepidoptera is basically different from that in other insects. The significance of the two-hit kinetics is discussed in relation to the chromosome structure and possible mechanisms for the induction of sterility in Lepidoptera. Many workers using Lepidoptera have reported that females mated to irradiated males oviposit substantially fewer eggs than normally. This response has been correlated to a lack of sperm transfer by irradiated males, even though they pass a spermatophore. The phenomenon is dose-dependent. Although Lepidoptera are far more radioresistant than other insect species when measured by the induction of sterility in the male, there appears to be very little difference when longevity is used as the criterion. The radiation dose required to reduce the lifespan of a newly emerged cabbage looper male by 50% was found to be approximately the same as that for the house fly. High doses of radiation have no immediate effect on the mating behaviour of the irradiated male. With a recessive eye-colour mutant as a sperm marker, it was determined in tests utilizing double matings that the second mating is the effective mating. Sperm mixing is not prevalent; rather it appears to be a 'sperm flushing' phenomenon in that sperm from the first mating are displaced by sperm from the second mating. Radiation studies with the cabbage looper have demonstrated that the progeny of a cross where the male parent receives a sub-sterilizing dose of gamma radiation are often semi-sterile when mated to non-irradiated individuals. The amount of inherited sterility is directly dependent on the amount of radiation given the

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)

Eugenics and Involuntary Sterilization: 1907-2015.

Science.gov (United States)

Reilly, Philip R

2015-01-01

In England during the late nineteenth century, intellectuals, especially Francis Galton, called for a variety of eugenic policies aimed at ensuring the health of the human species. In the United States, members of the Progressive movement embraced eugenic ideas, especially immigration restriction and sterilization. Indiana enacted the first eugenic sterilization law in 1907, and the US Supreme Court upheld such laws in 1927. State programs targeted institutionalized, mentally disabled women. Beginning in the late 1930s, proponents rationalized involuntary sterilization as protecting vulnerable women from unwanted pregnancy. By World War II, programs in the United States had sterilized approximately 60,000 persons. After the horrific revelations concerning Nazi eugenics (German Hereditary Health Courts approved at least 400,000 sterilization operations in less than a decade), eugenic sterilization programs in the United States declined rapidly. Simplistic eugenic thinking has faded, but coerced sterilization remains widespread, especially in China and India. In many parts of the world, involuntary sterilization is still intermittently used against minority groups.

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

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

Cytoembryologic study of gamma-ray induced sterile Pisum sativum L. mutants

International Nuclear Information System (INIS)

Molkhova, E.; Vasileva, M.

1977-01-01

Three new pea mutant forms are described - 1878, Crampled petal Waxless type, and Lathyrus type - which were induced by different gamma-ray ( 60 Co) doses and rates. The flowers of the 1878 and Crampled petal Waxless type mutants were very much deformed, while those of the Lathyrus type had smaller flowers with normal morphology. The three mutant forms were entirely sterile and were propagated by segregation in the progeny of heterozygous sister plants. PMC meiosis and the development of the male gametophyte of the Lathyrus type mutant had a normal course, while in the mutant forms Crampled petal Waxless type and 1878 slight disturbances were observed, but the pollen of all three mutants was not functional. The development of the female gametophyte of the three mutants stops at an early phase and only in the Lathyrus type mutant in single cases embryosacks were formed with differentiated sex apparatus and early stages of embryo and endosperm development were scored, but they also soon degenerate. It is pointed out that sterility of the three pea mutant forms studied depends on factors, which stop at different stages the normal development of the generative organs, of the female gametophyte and of embryogenesis. (author)

Improving hybrid seed production in corn with glyphosate-mediated male sterility.

Science.gov (United States)

Feng, Paul C C; Qi, Youlin; Chiu, Tommy; Stoecker, Martin A; Schuster, Christopher L; Johnson, Scott C; Fonseca, Augustine E; Huang, Jintai

2014-02-01

Hybrid corn varieties exhibit benefits associated with heterosis and account for most of the corn acreage in the USA. Hybrid seed corn is produced by crossing a female parent which is male-sterile and therefore incapable of self-pollination with a male parent as the pollen donor. The majority of hybrid seed corn is produced by mechanical detasseling which involves physically removing the tassel, a process that is laborious and costly. Glyphosate-resistant corn was developed via expression of a glyphosate insensitive 5-enolpyruvyl-shikimate 3-phosphate synthase enzyme (CP4-EPSPS). Experimentation with molecular expression elements resulted in selective reduction of CP4-EPSPS expression in male reproductive tissues. The resulting plant demonstrated sterile tassel following glyphosate application with little to no injury to the rest of the plant. Using (14)C-glyphosate as a marker, we also examined the translocation of glyphosate to the tassel via spray application in a track sprayer to simulate field application. The results allowed optimization of spray parameters such as dose, spray timing and target to maximize tassel delivery of glyphosate for efficient sterilization. The Roundup hybridization system (RHS) is a novel process for hybrid seed production based on glyphosate-mediated male sterility. RHS replaces mechanical detasseling with glyphosate spray and greatly simplifies the process of hybrid seed corn production. © 2013 Society of Chemical Industry.

Genetic analysis of a hybrid sterility gene that causes both pollen and embryo sac sterility in hybrids between Oryza sativa L. and Oryza longistaminata.

Science.gov (United States)

Chen, H; Zhao, Z; Liu, L; Kong, W; Lin, Y; You, S; Bai, W; Xiao, Y; Zheng, H; Jiang, L; Li, J; Zhou, J; Tao, D; Wan, J

2017-09-01

Oryza longistaminata originates from African wild rice and contains valuable traits conferring tolerance to biotic and abiotic stress. However, interspecific crosses between O. longistaminata and Oryza sativa cultivars are hindered by reproductive barriers. To dissect the mechanism of interspecific hybrid sterility, we developed a near-isogenic line (NIL) using indica variety RD23 as the recipient parent and O. longistaminata as the donor parent. Both pollen and embryo sac semi-sterility were observed in F 1 hybrids between RD23 and NIL. Cytological analysis demonstrated that pollen abortion in F 1 hybrids occurred at the early bi-nucleate stage due to a failure of the first mitosis in microspores. Partial embryo sacs in the F 1 hybrids were defective during the functional megaspore formation stage. Most notably, nearly half of the male or female gametes were aborted in heterozygotes S40 i S40 l , regardless of their genotypes. Thus, S40 was indicated as a one-locus sporophytic sterility gene controlling both male and female fertility in hybrids between RD23 and O. longistaminata. A population of 16 802 plants derived from the hybrid RD23/NIL-S40 was developed to fine-map S40. Finally, the S40 locus was delimited to an 80-kb region on the short arm of chromosome 1 in terms with reference sequences of cv. 93-11. Eight open reading frames (ORFs) were localized in this region. On the basis of gene expression and genomic sequence analysis, ORF5 and ORF8 were identified as candidate genes for the S40 locus. These results are helpful in cloning the S40 gene and marker-assisted transferring of the corresponding neutral allele in rice breeding programs.

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.

Sterile insect technique: A model for dose optimisation for improved sterile insect quality

International Nuclear Information System (INIS)

Parker, A.; Mehta, K.

2007-01-01

The sterile insect technique (SIT) is an environment-friendly pest control technique with application in the area-wide integrated control of key pests, including the suppression or elimination of introduced populations and the exclusion of new introductions. Reproductive sterility is normally induced by ionizing radiation, a convenient and consistent method that maintains a reasonable degree of competitiveness in the released insects. The cost and effectiveness of a control program integrating the SIT depend on the balance between sterility and competitiveness, but it appears that current operational programs with an SIT component are not achieving an appropriate balance. In this paper we discuss optimization of the sterilization process and present a simple model and procedure for determining the optimum dose. (author) [es

Sterile insect technique: new technology to control fruit flies, Ceratitis capitata, in the Lower Basin of the Sao Francisco Valley; Tecnica do inseto esteril: nova tecnologia para combater a mosca-das-frutas, Ceratitis capitata, no Submedio do Vale do Sao Francisco

Energy Technology Data Exchange (ETDEWEB)

Paranhos, Beatriz Aguiar Jordao; Barbosa, Flavia Rabelo [Embrapa Semi-Arido, Petrolina, PE (Brazil); Nascimento, Antonio Souza do [Embrapa Mandioca e Fruticultura, Cruz das Almas, BA (Brazil); Viana, Rodrigo; Malavasi, Aldo [Moscamed Brasil, Juazeiro, BA (Brazil); Sampaio, Raimundo [Agencia Estadual de Defesa Agropecuaria da Bahia (ADAB-BA), Salvador, BA (Brazil); Walder, Julio Marcos Melges [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

2008-12-15

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

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.

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

Science.gov (United States)

Reed, Laura K; LaFlamme, Brooke A; Markow, Therese A

2008-08-27

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. 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. 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.

Lack of insurance and parity influence choice between long-acting reversible contraception and sterilization in women postpregnancy.

Science.gov (United States)

Baldwin, Maureen K; Rodriguez, Maria I; Edelman, Alison B

2012-07-01

Disparities in postpregnancy contraception utilization exist, with low-income women disproportionately undergoing sterilization. We assessed the impact of increased intrauterine device (IUD) availability on rates of female sterilization. Hospital billing records were used to identify women with an IUD placement or sterilization within 1 year of a pregnancy at a university hospital between Oct 2005 and Jun 2007. Demographic data were compared between women receiving either an IUD or sterilization. There were 365 sterilizations and 223 IUD placements during the study period. IUD placements doubled over the study period from 6% to 12% of all deliveries, while sterilizations remained stable at 11% (pwomen with either public or private insurance who had financial access to both sterilization (n=253) and IUD (n=223). Women receiving sterilization were slightly older (mean age 31 years versus 30 years, p=.03), of higher parity (median three versus two, pwomen who received IUD. Approximately 45% of women delivering in Oregon in 2007 were publicly insured (2010 Maternal and Child Health Update: States Make Progress Towards Improving Systems of Care. National Governor's Association, Table 6. Available at http://www.nga.org/files/live/sites/NGA/files/pdf/MCHUPDATE2010.PDF, accessed Nov 2011). After adjusting for age, parity and type of delivery, women choosing sterilization were more likely to have public insurance than women choosing IUD (odds ratio 8.4, 95% confidence interval 4.7-14.9, pWomen choosing sterilization are more likely to have public insurance than women choosing IUD and may represent a continued trend toward nonreversible contraception among women of lower socioeconomic status despite available long-acting reversible methods. Copyright © 2012 Elsevier Inc. All rights reserved.

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)

Current attitudes toward, and incidence of, sterilization of cats and dogs by caregivers (owners) in Auckland, New Zealand.

Science.gov (United States)

McKay, Stacey A; Farnworth, Mark J; Waran, Natalie K

2009-01-01

This study distributed a questionnaire to cat or dog caregivers (owners) throughout Auckland, New Zealand, to investigate the attitudes of human companions toward the sterilization of their cats and dogs and the degree to which this occurs relative to demographic information gathered. A total of 276 recipients returned questionnaires with data pertinent to 477 cats and dogs. Female owners were more likely than were males to sterilize cats or dogs: 90.2% sterilization rate compared with 80%. Statistical trends also suggested that owners with a postschool education had a higher percentage of sterilized nonhuman animals than owners with no postschool or only school-age education. Cats were more likely than dogs to be neutered: 91.7% versus 78.5%. Companion animals not annually vaccinated were more likely to be sterilized than animals who were vaccinated annually: 93.6% and 85.4%. The study also showed gender bias and age differences in owner attitudes toward a number of the statements regarding sterilization, with male owners more likely to be concerned about the effect of neutering or spaying on the sexuality or masculinity of the animal.

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.

Gamma irradiation effects on some biological aspects of Ephestia Kuehniella (Zell.), inherited sterility and mating competitiveness

International Nuclear Information System (INIS)

EI-Orabi, M.N.; Sawires, S.G.; Antonious, A.G.; Salama, S.I.

2007-01-01

Full grown male and female pupae of the Mediterranean flour moth, Ephestia kuehniella (Zell.) were exposed to gamma irradiation doses ranging from 40 to 450 Gy. Irradiated males were more radio-resistant than females. Reduction in fecundity and egg hatch were dose-dependant. Irradiated males or females showed significant shorter lifespan than control group. Also, there were reductions in F 1 progeny as a result of irradiating male and female parents with sub-sterilizing doses, which were more apparent in irradiating of male parents. The average larval pupal developmental period of F1 male and female progeny was affected. The sex ratio of F 1 generation was shifted in favor of males. The parental males or females irradiated as full-grown pupae were affected with sub-sterilizing dose of 200 Gy for male line and 100 Gy for female line. All possible mating combinations in F1, F 2 and F3 of males and females lines were examined. Fecundity and fertility of F I adults descendant from irradiated male parents were significantly reduced than F1 adults descendant from irradiated female parents. Also, the number of laid eggs and percentage of egg hatch were reduced drastically in crosses of F 1 males mated to unirradiated females of male line. Fecundity and fertility of the different mating combinations among F2 generation for both male and female treated lines were significantly decreased than the unirradiated control. Also, the number of adults resulting from all mating crosses among F2 generation was greatly reduced as compared to control adult progeny. There was a recovery in reproductive potential in moths of third generation for irradiated male line and in the second generation of the irradiated female line

Male gametophytic sterility. 1 - Gametic sterilities and deletions in petunia

Energy Technology Data Exchange (ETDEWEB)

Cornu, A.; Maizonnier, D. (Station d' Amelioration des Plantes de l' I.N.R.A., Dijon (France))

1982-01-01

Terminal deletions induced by ionizing radiations in Petunia are not sexually transmitted. Cytogenetic study of plants with a heterozygous deletion and their progenies shows that this lack of transmission is accompanied by a gametic semi-sterility due to the fact that gametes carrying the deleted chromosome are not viable. The interest of such a male sterility with a gametophytic determinism for the study of sporophyte-gametophyte relationships is underlined.

Confirmation test for hysteroscopic sterilization: a descriptive study of patient tolerability and impressions

Directory of Open Access Journals (Sweden)

Chapa HO

2013-03-01

appointment (12%. Of the 70 HSGs performed, 69 revealed satisfactory micro insert positions with bilateral occlusion; one was unilaterally patent at 13 weeks post-sterilization, with satisfactory micro insert position. Repeat testing 10 weeks later documented bilateral occlusion.Conclusion: Confirmation testing for hysteroscopic sterilization is well tolerated, with favorable patient impressions after completion.Keywords: emale permanent birth control, female sterilization, Essure confirmation test, contraception

Gamma-ray irradiation, autoclave and ethylene oxide sterilization to thermosetting polyurethane: sterilization to polyurethane

International Nuclear Information System (INIS)

Hirata, Noriko; Matsumoto, Ken-Ichi; Inishita, Takashi; Takenaka, Yoshinori; Suma, Yasunori; Shintani, Hideharu; National Inst. of Health Sciences, Tokyo

1995-01-01

Thermosetting polyurethane (PU) is widely used in a large variety of medical devices. 4,4'-methylenedianiline (MDA) was produced from PU by sterilization and it was studied for the relationship between urethane components or polymer characteristics and formation of MDA upon sterilization, using the commercially available dialyzers fabricated with different combination of isocyanate and polyol. We confirmed that the molecular-weight of polyol influenced the production of MDA upon sterilization. (author)

"Forgotten" Chapters in the History of Transcervical Sterilization: Carl Clauberg and Hans-Joachim Lindemann.

Science.gov (United States)

Hildebrandt, Sabine; Benedict, Susan; Miller, Erin; Gaffney, Michael; Grodin, Michael A

2017-07-01

Transcervical sterilization is a non-surgical method of permanent female sterilization that is widely used and critically discussed. A review of the historiography of the method reveals that instances of its coercive use are not included in the historical account. This study offers a reexamination of the work of Carl Clauberg and Hans-Joachim Lindemann, to more deeply contextualize within the framework of current usage the coercive use of transcervical sterilization during the Third Reich and in postwar Germany. This inquiry is based on postwar criminal trial records on Clauberg, and on archival documents detailing Lindemann's activities in 1979. A comparative analysis examines arguments by medical historian Karl-Heinz Roth, and identifies shared characteristics and differences between Clauberg and Lindemann, their methods and scientific connections. The results demonstrate that the technique of transcervical sterilization has an abusive potential that may be explained as a function of the person of the physician, of the scientific method itself, and of societal and political influences. The analysis supports the argument that insights from the cases of Clauberg and Lindemann are transferrable geographically and over time, and have the potential to inform current medical practice, such as transcervical sterilization with the Essure device, whose historiographic exploration remains a desideratum. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

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

Science.gov (United States)

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

2017-12-01

There is still limited quantitative understanding of how environmental factors affect sterility of Environment-conditioned genic male sterility (EGMS) lines. A model was developed for this purpose and tested based on experimental data from Ndiaye (Senegal) in 2013-2015. For the two EGMS lines tested here, it was not clear if one or more recessive gene(s) were causing male sterility. This was tested by studying sterility segregation of the F2 populations. Daylength (photoperiod) and minimum temperatures during the period from panicle initiation to flowering had significant effects on male sterility. Results clearly showed that only one recessive gene was involved in causing male sterility. The model was applied to determine the set of sowing dates of two different EGMS lines such that both would flower at the same time the pollen would be completely sterile. In the same time the local popular variety (Sahel 108, the male pollen donor) being sufficiently fertile to produce the hybrid seeds. The model was applied to investigate the viability of the two line breeding system in the same location with climate change (+2oC) and in two other potential locations: in M'Be in Ivory Coast and in the Nile delta in Egypt. Apart from giving new insights in the relation between environment and EGMS, this study shows that these insights can be used to assess safe sowing windows and assess the suitability of sterility and fertility period of different environments for a two line hybrid rice production system.

Materials Surfaces and sterility

Energy Technology Data Exchange (ETDEWEB)

Schmidt, R.

2001-04-01

A question of great interest in sterile and clean room technology is how can we devise a standard for the guarantee of sterility? Sterility is of widespread importance: it gives the life-time of our daily milk or yogurt, dominates the nature of food packing, and determines the feasibility of the miniaturization of biotechnology plants. All these phenomena are based on the principle of bioadhesion. Bioadhesion is also the basis of the biomimetic material technologies, like the attachment of selected protein layers that can be used for nanomasking. (orig.)

Genetic technologies to enhance the Sterile Insect Technique (SIT)

International Nuclear Information System (INIS)

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

2006-01-01

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

Genetic technologies to enhance the Sterile Insect Technique (SIT)

Energy Technology Data Exchange (ETDEWEB)

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

2006-07-01

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

Steam sterilization does not require saturated steam

NARCIS (Netherlands)

van Doornmalen Gomez Hoyos, J. P.C.M.; Paunovic, A.; Kopinga, K.

2017-01-01

The most commonly applied method to sterilize re-usable medical devices in hospitals is steam sterilization. The essential conditions for steam sterilization are derived from sterilization in water. Microbiological experiments in aqueous solutions have been used to calculate various time–temperature

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.

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.

Sterilization of 4-5-day-old pupae of the Indian meal moth with gamma radiation and its effect on mating competitiveness

International Nuclear Information System (INIS)

Ahmed, M.Y.Y.; Brower, J.H.; Tilton, E.W.

1978-01-01

Females of the Indian meal moth, Plodia interpunctella (Huebner), irradiated as 4-5-day-old pupae with an absorbed dose of 35 krad of gamma radiation and confined with unirradiated (U) males were sterile. Male moths treated similarly and confined with U females were only partially sterile. Irradiated (I) males confined with U males and females at a ratio of 1:1:1 caused 18.2% of the eggs produced to be infertile; increasing the ratio to 5:1:1, 10:1:1, 15:1:1 and 25:1:1 caused 48.7, 46.6, 47.7 and 58.9%, respectively, infertile eggs. The calculated competitiveness values (CV) for the 5 ratios were 0.39, 0.70, 0.63, 0.62 and 0.75, respectively. When I females were confined with U males and females in the same 5 ratios: 1:1:1, 5:1:1, etc., 15.6, 66.2, 74.3, 100.0 and 100.0% respectively, of the eggs were infertile. The CVs calculated for these ratios were 0.73, 1.52, 1.28, 1.50 and 1.30. Thus, I females were more effective in reducing egg fertility than were I males. (author)

Effect of irradiation sterilizing dose on the mating competitiveness of Trogoderma Granarium Everts treated as adults at different ages

International Nuclear Information System (INIS)

Gharieb, O.H.

2002-01-01

Males of Trogoderma Granarium at ages of 1, 3, 5 and 7 days were irradiated with 200 GY (sterilizing dose) and combined with the same ages of the normal males mated with 1-d-old females. (I male : u male : U ) in the fohowing ratios of (1:1:1), (5:1:1), (10:1:1) and (15:1:1). At 15 irradiated males per pair, egg hatch was reduced to 4.5 and 2.2% at male ages of 1 and 3 d-old, respectively, but, it was 4.9 and 7.5 at male ages of 5 and 7 d-old, respectively. The calculated degree of mating competitiveness at this ratio was 1.10, 1.03, 0.97 and 0.94 for the corresponding ages. Females at the aformentioned ages irradiated with 60 GY (sterilizing dose) and competed with normal females for normal males. At 15 irradiated females per pair, the egg hatch was reduced to 5.4, 2.1, 1.8 and 1.4 % for the corresponding ages tested. Therefore, (I) females showed good competitiveness at most release ratios, but (I) females were fully competitive (1.00) at the higher release ratio I:U females (15:1). In general, (I) females were more competitive (based on number of eggs per female and percent infertility) than the corresponding (I) males especially at later ages (5 and 7 d-old adults) even, at the higher release ratios. =

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.

21 CFR 522.1862 - Sterile pralidoxime chloride.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sterile pralidoxime chloride. 522.1862 Section 522....1862 Sterile pralidoxime chloride. (a) Chemical name. 2-Formyl-1-methylpyridinium chloride oxime. (b) Specifications. Sterile pralidoxime chloride is packaged in vials. Each vial contains 1 gram of sterile...

Preliminary studies on inherited sterility for field management of diamondback moth (plutella xylostella) (Lepidoptera: plutellidae) on crucifiers in Ghana

International Nuclear Information System (INIS)

Ewusie, E.A.; Nkumsah, A.K.; Alimatu, S.; Osae, M.Y.

2010-01-01

The diamondback moth (DBM), plutella xylostella (L.) (Lepidoptera: plutellidae) is the most destructive insect pest crucifiers in Ghana and the world over. It is estimated to cost about USD 1 billion to control annually worldwide. Reliance on chemicals as the sole control measure for diamondback moth has resulted in the development of a myriad of problems including resistance, high residue levels on produce, destruction of natural enemies and pest resurgence among others. Inherited sterility in Lepidoptera insects has a potential for suppressing DBM populations. We conducted this study to evaluate the use of the technique to manage the diamond back moth in Ghana. When 3 - 4 day old pupae were treated with 130 Gy and 150 Gy of gamma radiation, 47% and 46% respectively of the male pupae developed as normal adults while 40% and 17% respectively of the female pupae developed as normal adults. However, radiation-induced reductions in fecundity and egg viability were expressed in the parental and first filial (F 1 ) generations. Sterility exceeded 66% in the treated parental male and 92% in the treated parental female in both treatments as compared with 78% and 95% in treated F 1 male and female, respectively. The sex ratio was skewed in favour of males in the parental progeny. These results indicate the possibility of using inherited sterility for DBM control. (au)

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.)

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.)

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....

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.)

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.

Sterilization can change properties of bioceramics

International Nuclear Information System (INIS)

Willmann, G.

2003-01-01

Bioceramics made of bioinert alumina or zirconia and bioactive hydroxyapatite are well established implant materials. Implants have to be cleaned and sterilized. When sterilized some bioceramics change their color. This may effect their properties. No decrease of mechanical strength is observed when sterilizing alumina and the novel ceramic biocomposite AMC (Alumina Matrix Composite) with steam or Co 60 Gamma irradiation. When sterilizing Y-TZP zirconia with steam a decrease of strength is observed. (Abstract Copyright [2003], Wiley Periodicals, Inc.) [de

International Standards for Radiation Sterilization of Medical Devices

International Nuclear Information System (INIS)

Miller, A.

2007-01-01

For a terminally sterilized medical device to be designated '' STERILE '', probability of finding the viable micro-organisms in the device shall be equal to or less than 1 x 10 -6 (EN 556-1:2001: Sterilization of medical devices - Requirements for medical devices to be designated '' STERILE '' - Part 1: Requirements for terminally sterilized medical devices). Author presents the main legal aspects of the international standards for radiation sterilization of medical devices

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.

Construction of a male sterility system for hybrid rice breeding and seed production using a nuclear male sterility gene

OpenAIRE

Chang, Zhenyi; Chen, Zhufeng; Wang, Na; Xie, Gang; Lu, Jiawei; Yan, Wei; Zhou, Junli; Tang, Xiaoyan; Deng, Xing Wang

2016-01-01

Nuclear male sterility is common in flowering plants, but its application in hybrid breeding and seed production is limited because of the inability to propagate a pure male sterile line for commercial hybrid seed production. Here, we characterized a rice nuclear gene essential for sporophytic male fertility and constructed a male sterility system that can propagate the pure male sterile seeds on a large scale. This system is fundamentally advantageous over the current cytoplasmic male steril...

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

The male gametophytic sterility. 1 - Gametic sterilities and deletions in petunia

International Nuclear Information System (INIS)

Cornu, A.; Maizonnier, D.

1982-01-01

Terminal deletions induced by ionizing radiations in Petunia are not sexually transmitted. Cytogenetic study of plants with a heterozygous deletion and their progenies shows that this lack of transmission is accompanied by a gametic semi-sterility due to the fact that gametes carrying the deleted chromosome are not viable. The interest of such a male sterility with a gametophytic determinism for the study of sporophyte-gametophyte relationships is underlined [fr

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.

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

Assessing the putative roles of X-autosome and X-Y interactions in hybrid male sterility of the Drosophila bipectinata species complex.

Science.gov (United States)

Mishra, Paras Kumar; Singh, Bashisth Narayan

2007-07-01

Interspecific F1 hybrid males of the Drosophila bipectinata species complex are sterile, while females are fertile, following Haldane's rule. A backcross scheme involving a single recessive visible marker on the X chromosome has been used to assess the putative roles of X-autosome and X-Y interactions in hybrid male sterility in the D. bipectinata species complex. The results suggest that X-Y interactions are playing the major role in hybrid male sterility in the crosses D. bipectinata x D. parabipectinata and D. bipectinata x D. pseudoananassae, while X-autosome interactions are largely involved in hybrid male sterility in the crosses D. malerkotliana x D. bipectinata and D. malerkotliana x D. parabipectinata. However, by using this single marker it is not possible to rule out the involvement of autosome-autosome interactions in hybrid male sterility. These findings also lend further support to the phylogenetic relationships among 4 species of the D. bipectinata complex.

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

International Nuclear Information System (INIS)

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

1996-01-01

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

[Legal statutes on sterilization].

Science.gov (United States)

Zupancic, K

1980-01-01

Sterilization in Yugoslavia is no population policy measure. Decision about the birth of children is free, a private problem of any individual, a basic right guaranteed by the Constitution. However, according to certain laws in Slovenia and Croatia, sterilization is allowed as a family planning method in persons over 35 year old. Only exceptionally can sterilization be applied in persons younger than 35 years: according to the Slovenian law, in cases when a person lacks the capacity of reasoning and also when there are medical indications, and according to the Croatian law, when there are medical and eugenic reasons (if the child is supposed to be born with negative congenital properties).

Electron sterilization validation techniques using the controlled depth of sterilization process

International Nuclear Information System (INIS)

Cleghorn, D.A.; Nablo, S.V.

1990-01-01

Many pharmaceutical products, especially parenteral drugs, cannot be sterilized with gamma rays or high energy electrons due to the concomitant product degradation. In view of the well-controlled electron energy spectrum available in modern electron processors, it is practical to deliver sterilizing doses over depths considerably less than those defining the thickness of blister-pack constructions or pharmaceutical containers. Because bremsstrahlung and X-ray production are minimized at these low electron energies and in these low Z materials, very high electron: penetrating X-ray dose ratios are possible for the application of the technique. Thin film dosimetric techniques have been developed utilizing radiochromic film in the 10-60 g/m 2 range for determining the surface dose distribution in occluded surface areas where direct electron illumination is not possible. Procedures for validation of the process using dried spore inoculum on the product as well as in good geometry are employed to determine the process lethality and its dependence on product surface geometry. Applications of the process to labile pharmaceuticals in glass and polystyrene syringes are reviewed. It has been applied to the sterilization of commercial sterile products since 1987, and the advantages and the natural limitations of the technique are discussed. (author)

Male sterility in chestnuts

International Nuclear Information System (INIS)

Omura, Mitsuo; Akihama, Tomoya

1982-01-01

A tentative plan was proposed for chestnuts based on their pollination system, male sterility and restoration. The studies on the male sterility of 1,063 cultivars and clones suggested that there were three types of male sterility. The first type (S-1) was characterized by antherless florets. In the second type (S-2), the catkins fell before anthesis, and the third type (S-3) appeared to develop normally in gross floral morphology, but the pollen grains were abnormal in shape and did not have germinating power. In an interspecific hybrid clone CS which belonged to S-1, fertility was restored in an open pollinated progeny. The use of CS and CSO-3 with its restored fertility, permitted the planning of breeding the chestnut hybrid cultivars propagated by seeds. The inbred clones with either male sterility or restorer genes are first bred mainly by back crossing with parents with favorable pollen. The clones are selected individually for early bearing, wasp and disease resistance, and restoration. Then, the hybrid seedling lines between male sterile and restorer inbreds are evaluated for homogenity in nut characters and tree habits. Next, the hybrid seedling lines selected will be examined for crop yield, vigor and cross compatibility. The superior seedling lines are finally selected, and the parental inbreds are grafted to be propagated for seed production orchards. (Kaihara, S.)

Gamma sterilization of disposable medical products (DMP's)

International Nuclear Information System (INIS)

Brinston, R.M.

1990-01-01

Ten million cubic meters (361 million cubic feet) of disposable medical products (DMP) and related health care items are estimated to be sterilized in the world. In this paper, current conditions and perspectives of gamma sterilization is discussed in comparison with ethylene oxide gas and electron beams. Of the total sterilization estimates for DMP, 2.8 million cubic meters (99 million cubic feet) are sterilized with gamma radiation, with a market share of 27%. Gamma radiation is becoming increased from both general market growth and the introduction of new products, as well as the conversion of product from ethylene oxide gas to cobalt-60. Regulatory pressures, legal considerations, and increasing publicity surrounding ethylene oxide usage are encouraging manufactures to switch to gamma radiation. Gamma's performance features include: no temperature change during the sterilization, high penetration, even through hermetically sealed packages, no residues, and no post-sterilization treatment or quarantine period. Gamma sterilization is economically beneficial in large volumes of product. Cost saving to the end user of gamma sterilization has meant lower minimum dose levels than 25 KGy. Despite of an increasingly accepted gamma radiation, there are still four factors to be considered, including cobalt-60 availability, price, transportation, and disposal. The price of cobalt-60 is based on neutron cost. In the future, cobalt-60 price is expected to be flat and enables gamma processing to become even more competitive with other sterilization methods. Gamma radiation using cobalt-60 has been proven as a safe, effective, and cost-competitive sterilization method for treating DMP and related health care items. It's wide use and many processing advantages will continue to make it a preferred sterilization method. (N.K.)

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

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.

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.

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

International Nuclear Information System (INIS)

Kamburov, S.S.; Yawetz, A.

1975-01-01

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

Sterility induction in tsetse

Energy Technology Data Exchange (ETDEWEB)

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

1982-01-01

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

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

Sterile mutant of Verbena hybrida induced by heavy ion beam irradiation and wild species V. peruviana exhibit self-incompatible phenotype

International Nuclear Information System (INIS)

Saito, H.; Hayashi, Y.; Abe, T.; Kanaya, T.; Suzuki, K.

2005-01-01

Full text: Garden verbenas (Verbena hybrida) belonging to the Verbenaceae family are originated from interspecific hybridization among several species, many cultivars frequently produce seeds. Recently, a sterile mutant has been isolated in the verbena cultivar 'Coral Pink' of Temari series (Suntory Flowers Ltd., Tokyo, Japan) by mutation induction using heavy-ion beams at RIKEN Accelarator Research Facility (RARF, Saitama, Japan). We investigated pollen and ovule fertility assessed by acetocarmin staining, seed-set following controlled-pollination tests and behavior of pollen tubes in pistils with the sterile mutant of 'Coral Pink' (SC) and its original fertile one (FC). As the results, although SC has functional male and female gametes, few self-pollinated flowers carry out seed-set, leading to sterile phenotype. Additionally, the sterile mechanism of SC was compared with the wild species V. peruviana (VP) which is one of origin of Temari series and exhibits sterility. Interestingly, similar phenotype was observed in PV. We further investigated, therefore, whether there are differences on self-incompatible reaction between SC and VP. (author)

Sterile mutant of Verbena hybrida induced by heavy ion beam irradiation and wild species V. peruviana exhibit self-incompatible phenotype

Energy Technology Data Exchange (ETDEWEB)

Saito, H; Hayashi, Y; Abe, T [RIKEN, Wako (Japan); Kanaya, T; Suzuki, K [Suntory Flowers Ltd., Higashiomi (Japan)

2005-07-01

Full text: Garden verbenas (Verbena hybrida) belonging to the Verbenaceae family are originated from interspecific hybridization among several species, many cultivars frequently produce seeds. Recently, a sterile mutant has been isolated in the verbena cultivar 'Coral Pink' of Temari series (Suntory Flowers Ltd., Tokyo, Japan) by mutation induction using heavy-ion beams at RIKEN Accelarator Research Facility (RARF, Saitama, Japan). We investigated pollen and ovule fertility assessed by acetocarmin staining, seed-set following controlled-pollination tests and behavior of pollen tubes in pistils with the sterile mutant of 'Coral Pink' (SC) and its original fertile one (FC). As the results, although SC has functional male and female gametes, few self-pollinated flowers carry out seed-set, leading to sterile phenotype. Additionally, the sterile mechanism of SC was compared with the wild species V. peruviana (VP) which is one of origin of Temari series and exhibits sterility. Interestingly, similar phenotype was observed in PV. We further investigated, therefore, whether there are differences on self-incompatible reaction between SC and VP. (author)

Dynamic sterilization of titanium implants with ultraviolet light

International Nuclear Information System (INIS)

Singh, S.; Schaaf, N.G.

1989-01-01

All implantable devices must be sterile. However, autoclaves produce poor surface properties that jeopardize the integration process. The application of a modified ultraviolet light source has proven to enhance bioreactivity by controlling surface properties, but it lacks validation of its sterilization capabilities. Forty-eight titanium implants were contaminated with spores of the biological indicator Bacillus stearothermophilus and subjected to dynamic sterilization by ultraviolet light. Forty-seven of the implants were successfully sterilized, as indicated by not producing turbidity in a suitable growth medium. This sterilization technique only requires a 20-second exposure to achieve sterility

Evaluation of Influencing Factors on Tubal Sterilization Regret: A Cross-Sectional Study

Directory of Open Access Journals (Sweden)

Shahideh Jahanian Sadatmahalleh

2018-06-01

Full Text Available Background The aim of this study is to evaluate the menstrual pattern, sexual function, and anxiety, and depression in women with poststerilization regret, and potential influencing factors for regret following tubal ligation (TL in Iranian women. Materials and Methods In this cross-sectional study, 166 women with TL were subdivided into two groups including women with poststerilization regret (n=41 and women without poststerilization regret (n=125. They were selected from a health care center in Guilan province (Iran during 2015-2016. Menstrual blood loss was measured using the Pictorial Blood Loss Assessment Chart (PBLAC and through a self-administered questionnaire. In addition, sexual function was assessed by the Female Sexual Function Index (FSFI, and psychological distress was measured by employing the Hospital Anxiety and Depression Scale (HADS. Student’s t test and Chi-square test were used to reveal the statistical differences between the two groups. We used logistic regression to determine the influencing factors associated with regretting sterilization. Results Women with poststerilization regret had more menorrhagia (78 vs. 57.6%, P=0.03 than those who did not regret sterilization. A significant difference was found in sexual dysfunction in orgasm (P=0.02, satisfaction (P=0.004, pain (P=0.02, and total FSFI scores (P=0.007 between the two groups. Also, there was a significant difference between the two groups in anxiety, depression and total scores HADS (P=0.01. In the logistic regression model, age of sterilization [odds ratio (OR=2.67, confidence interval (CI: 1.03-7.81, P=0.04], pre-sterilization counseling (OR=19.92, CI: 6.61-59.99, P<0.001, score of PBLAC (OR=1.01, CI: 1.004-1.01, P=0.001, the number of days of bleeding (OR=1.37, CI: 1.01-1.99, P=0.04, and the length of menstrual cycles (OR=0.91, CI: 0.84-0.99, P=0.03 were significantly associated with regretting sterilization. Conclusion Complications due to sterilization are

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.

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.

The Trojan Female Technique: A Novel, Effective and Humane Approach for Pest Population Control

Energy Technology Data Exchange (ETDEWEB)

Gemmell, Neil J. [Centre for Reproduction and Genomics and Allan Wilson Centre for Molecular Ecology and Evolution, Department of Anatomy, University of Otago, Dunedin (New Zealand); Jalilzadeh, Aidin [Department of Mathematics and Statistics, University of Otago, Dunedin (New Zealand); Didham, Raphael K. [School of Animal Biology, University of Western Australia (Australia); CSIRO Ecosystem Sciences, Perth, Western Australia (Australia); Soboleva, Tanya [Science and Risk Assessment Directorate, Ministry for Primary Industries, PO Box 2526, Wellington (New Zealand); Tompkins, Daniel M. [Landcare Research, Private Bag 1930, Dunedin (New Zealand); New Zealand Institute for Plant and Food Research Ltd., Christchurch (New Zealand)

2014-01-15

Full-text: Humankind's ongoing battle with pest species spans millennia. Pests cause or carry disease, damage or consume food crops and other resources, and drive global environmental change. Conventional approaches to pest management usually involve lethal control, but such approaches are costly, of varying efficiency and often have ethical issues. Thus, pest management via control of reproductive output is increasingly considered an optimal solution. One of the most successful such 'fertility control' strategies developed to date is the sterile male technique (SMT), in which large numbers of sterile males are released into a population each generation. However, this approach is time-consuming, labour- intensive and costly. We use mathematical models to test a new twist on the SMT, using maternally inherited mitochondrial (mtDNA) mutations that affect male, but not female reproductive fitness. 'Trojan females' carrying such mutations, and their female descendants, produce 'sterile-male'-equivalents under natural conditions over multiple generations. We find that the Trojan Female Technique (TFT) has the potential to be a novel humane approach for pest control. Single large releases and relatively few small repeat releases of Trojan females both provided effective and persistent control within relatively few generations. Although greatest efficacy was predicted for high-turnover species, the additive nature of multiple releases made the TFT applicable to the full range of life histories modelled. The extensive conservation of mtDNA among eukaryotes suggests this approach could have broad utility for pest control. (author)

The Trojan female technique: a novel, effective and humane approach for pest population control.

Science.gov (United States)

Gemmell, Neil J; Jalilzadeh, Aidin; Didham, Raphael K; Soboleva, Tanya; Tompkins, Daniel M

2013-12-22

Humankind's ongoing battle with pest species spans millennia. Pests cause or carry disease, damage or consume food crops and other resources, and drive global environmental change. Conventional approaches to pest management usually involve lethal control, but such approaches are costly, of varying efficiency and often have ethical issues. Thus, pest management via control of reproductive output is increasingly considered an optimal solution. One of the most successful such 'fertility control' strategies developed to date is the sterile male technique (SMT), in which large numbers of sterile males are released into a population each generation. However, this approach is time-consuming, labour-intensive and costly. We use mathematical models to test a new twist on the SMT, using maternally inherited mitochondrial (mtDNA) mutations that affect male, but not female reproductive fitness. 'Trojan females' carrying such mutations, and their female descendants, produce 'sterile-male'-equivalents under natural conditions over multiple generations. We find that the Trojan female technique (TFT) has the potential to be a novel humane approach for pest control. Single large releases and relatively few small repeat releases of Trojan females both provided effective and persistent control within relatively few generations. Although greatest efficacy was predicted for high-turnover species, the additive nature of multiple releases made the TFT applicable to the full range of life histories modelled. The extensive conservation of mtDNA among eukaryotes suggests this approach could have broad utility for pest control.

Genomic networks of hybrid sterility.

Science.gov (United States)

Turner, Leslie M; White, Michael A; Tautz, Diethard; Payseur, Bret A

2014-02-01

Hybrid dysfunction, a common feature of reproductive barriers between species, is often caused by negative epistasis between loci ("Dobzhansky-Muller incompatibilities"). The nature and complexity of hybrid incompatibilities remain poorly understood because identifying interacting loci that affect complex phenotypes is difficult. With subspecies in the early stages of speciation, an array of genetic tools, and detailed knowledge of reproductive biology, house mice (Mus musculus) provide a model system for dissecting hybrid incompatibilities. Male hybrids between M. musculus subspecies often show reduced fertility. Previous studies identified loci and several X chromosome-autosome interactions that contribute to sterility. To characterize the genetic basis of hybrid sterility in detail, we used a systems genetics approach, integrating mapping of gene expression traits with sterility phenotypes and QTL. We measured genome-wide testis expression in 305 male F2s from a cross between wild-derived inbred strains of M. musculus musculus and M. m. domesticus. We identified several thousand cis- and trans-acting QTL contributing to expression variation (eQTL). Many trans eQTL cluster into eleven 'hotspots,' seven of which co-localize with QTL for sterility phenotypes identified in the cross. The number and clustering of trans eQTL-but not cis eQTL-were substantially lower when mapping was restricted to a 'fertile' subset of mice, providing evidence that trans eQTL hotspots are related to sterility. Functional annotation of transcripts with eQTL provides insights into the biological processes disrupted by sterility loci and guides prioritization of candidate genes. Using a conditional mapping approach, we identified eQTL dependent on interactions between loci, revealing a complex system of epistasis. Our results illuminate established patterns, including the role of the X chromosome in hybrid sterility. The integrated mapping approach we employed is applicable in a broad

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.

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.

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

Hybrid Sterility Locus on Chromosome X Controls Meiotic Recombination Rate in Mouse.

Directory of Open Access Journals (Sweden)

Maria Balcova

2016-04-01

Full Text Available Meiotic recombination safeguards proper segregation of homologous chromosomes into gametes, affects genetic variation within species, and contributes to meiotic chromosome recognition, pairing and synapsis. The Prdm9 gene has a dual role, it controls meiotic recombination by determining the genomic position of crossover hotspots and, in infertile hybrids of house mouse subspecies Mus m. musculus (Mmm and Mus m. domesticus (Mmd, it further functions as the major hybrid sterility gene. In the latter role Prdm9 interacts with the hybrid sterility X 2 (Hstx2 genomic locus on Chromosome X (Chr X by a still unknown mechanism. Here we investigated the meiotic recombination rate at the genome-wide level and its possible relation to hybrid sterility. Using immunofluorescence microscopy we quantified the foci of MLH1 DNA mismatch repair protein, the cytological counterparts of reciprocal crossovers, in a panel of inter-subspecific chromosome substitution strains. Two autosomes, Chr 7 and Chr 11, significantly modified the meiotic recombination rate, yet the strongest modifier, designated meiotic recombination 1, Meir1, emerged in the 4.7 Mb Hstx2 genomic locus on Chr X. The male-limited transgressive effect of Meir1 on recombination rate parallels the male-limited transgressive role of Hstx2 in hybrid male sterility. Thus, both genetic factors, the Prdm9 gene and the Hstx2/Meir1 genomic locus, indicate a link between meiotic recombination and hybrid sterility. A strong female-specific modifier of meiotic recombination rate with the effect opposite to Meir1 was localized on Chr X, distally to Meir1. Mapping Meir1 to a narrow candidate interval on Chr X is an important first step towards positional cloning of the respective gene(s responsible for variation in the global recombination rate between closely related mouse subspecies.

Hybrid Sterility Locus on Chromosome X Controls Meiotic Recombination Rate in Mouse.

Science.gov (United States)

Balcova, Maria; Faltusova, Barbora; Gergelits, Vaclav; Bhattacharyya, Tanmoy; Mihola, Ondrej; Trachtulec, Zdenek; Knopf, Corinna; Fotopulosova, Vladana; Chvatalova, Irena; Gregorova, Sona; Forejt, Jiri

2016-04-01

Meiotic recombination safeguards proper segregation of homologous chromosomes into gametes, affects genetic variation within species, and contributes to meiotic chromosome recognition, pairing and synapsis. The Prdm9 gene has a dual role, it controls meiotic recombination by determining the genomic position of crossover hotspots and, in infertile hybrids of house mouse subspecies Mus m. musculus (Mmm) and Mus m. domesticus (Mmd), it further functions as the major hybrid sterility gene. In the latter role Prdm9 interacts with the hybrid sterility X 2 (Hstx2) genomic locus on Chromosome X (Chr X) by a still unknown mechanism. Here we investigated the meiotic recombination rate at the genome-wide level and its possible relation to hybrid sterility. Using immunofluorescence microscopy we quantified the foci of MLH1 DNA mismatch repair protein, the cytological counterparts of reciprocal crossovers, in a panel of inter-subspecific chromosome substitution strains. Two autosomes, Chr 7 and Chr 11, significantly modified the meiotic recombination rate, yet the strongest modifier, designated meiotic recombination 1, Meir1, emerged in the 4.7 Mb Hstx2 genomic locus on Chr X. The male-limited transgressive effect of Meir1 on recombination rate parallels the male-limited transgressive role of Hstx2 in hybrid male sterility. Thus, both genetic factors, the Prdm9 gene and the Hstx2/Meir1 genomic locus, indicate a link between meiotic recombination and hybrid sterility. A strong female-specific modifier of meiotic recombination rate with the effect opposite to Meir1 was localized on Chr X, distally to Meir1. Mapping Meir1 to a narrow candidate interval on Chr X is an important first step towards positional cloning of the respective gene(s) responsible for variation in the global recombination rate between closely related mouse subspecies.

Sterilization of instruments in solar ovens

Energy Technology Data Exchange (ETDEWEB)

Fjendbo Joergensen, A. [Odense Univ. Hospital, Dept. of Infectious Diseases, Odense (Denmark); Noehr, K. [Odense Technical College, Dept. of Metal, Odense (Denmark); Boisen, F. [The Danish Veterinary and Food Administration Funen, Dept. of Microbiology, Odense (Denmark)

2000-07-01

The sterilization of instruments in rural health clinics in less developed countries is an increasing problem because chemical methods can no longer be recommended and wood fuel is becoming more and more scarce. Thus, it seemed obvious to try to utilize solar energy for sterilization purposes. A solar oven was designed and manufactured using local materials and simple tools. The solar oven was tested by physical, chemical, and microbiological methods. A mathematical model for the sterilization effect was developed and programmed into a microprocessor that was connected to a thermocouple. The microprocessor switches on a green light when the sterilization is completed. After successful testing, the oven was built into the west-facing wall of a rural health clinic and used daily for sterilization. The oven was able to generate temperatures above 180 deg. C. On all days with direct sunlight the oven fulfilled the international recommendations for hot air sterilization because no growth could be detected from any of the test bacteria spores. The chemical indicators Brownes tubes types 3 and 5 also changed colours. The solar oven was easy to use for the clinic staff, but during the seasons with low sun position (in Tanzania, December and June) it was difficult to achieve a high enough temperature for sterilization. Therefore, if the method is to be used throughout the year the oven must be moved to collect the sun's rays from several directions, or the clinic must have more than one solar oven facing in different directions. We conclude that the solar oven is a realistic method for sterilization of instruments. (au)

Aspectos positivos e negativos da esterilização tubária do ponto de vista de mulheres esterilizadas Positive and negative aspects of Fallopian tube sterilization as viewed by sterilized women

Directory of Open Access Journals (Sweden)

Luzinete Simões Minella

1998-01-01

Full Text Available O objetivo deste artigo consiste em tratar os aspectos positivos e negativos da esterilização feminina, de acordo com o ponto de vista de dois grupos de mulheres esterilizadas em Florianópolis, Santa Catarina, Brasil, a partir de uma discussão sociológica sobre o seu estado de saúde atual, avaliando-se as relações que costumam fazer entre este estado e a condição de esterilizada. O primeiro grupo está constituído por mulheres provenientes de um bairro de baixa renda, predominantemente donas de casa, e o segundo grupo inclui funcionárias públicas, estudantes e professoras universitárias, provenientes dos setores médios da sociedade, totalizando quarenta mulheres. A metodologia da pesquisa baseou-se em um questionário estruturado com perguntas abertas de modo a registrar tanto aspectos ligados a variáveis sócio-econômicas e demográficas, quanto dados subjetivos ligados às representações das mulheres sobre o período pós-esterilização. Além de uma série de outros aspectos, tornou-se possível concluir que não existe consenso sobre as conseqüências da esterilização, tendo-se constatado a existência de uma proporção significativa de mulheres esterilizadas (11 principalmente antes dos 30 anos que percebem alterações de saúde após a laqueadura.The objective of this paper is to point out the positive and negative aspects of female sterilization as seen by two groups of sterilized women in Florianópolis, Santa Catarina, Brazil, based on a sociological discussion of their present health status, evaluating the associations that they generally make with the fact that they have been sterilized. The first group included mostly housewives from a low-income neighborhood, while the second involved upper-middle-class female public employees, students, and university professors, totaling 40 women. Data were obtained through a structured questionnaire with open-ended questions. Information on social, economic, and

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)

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

Science.gov (United States)

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

2010-01-01

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

Compodock, a new device for sterile docking

NARCIS (Netherlands)

van der Meer, P. F.; Biekart, F. T.; Pietersz, R. N.; Rebers, S. P.; Reesink, H. W.

2000-01-01

BACKGROUND: A new device for sterile docking, the Compodock (Fresenius NPBI Transfusion Technology), was developed for connecting PVC tubing for medical use while maintaining sterility. STUDY DESIGN AND METHODS: Sterility of the connections was assessed by welding tubing with a heavy exterior

Pilot application of sterile insect technique for the oriental fruit fly, Bactrocera Philippinensis, in Naoway islet

International Nuclear Information System (INIS)

Manoto, E.C.; Resilva, S.S.; Obra, G.B.; Reyes, M.R.; Golez, H.G.; Covacha, S.A.; Bignayan, H.G.; Zamora, N.F.; Gaitan, E.D.

1996-01-01

The sterile insect technique for the Oriental fruit fly was pilot tested in Naoway, a 12-ha islet about 1.5 km. southeast of Guimaras island. The Oriental fruit fly population (male) in the islet was first estimated at 3,432 using the mark-release-recapture experiments. From August to October 1995, six releases of sterile fruit flies (male and female) at biweekly intervals were conducted in the islet. Except for the 7 wild fruit flies collected by a trap 10 days after the first release, not a single fly was collected from the pilot site thereafter. Furthermore, field collections of infested fruits yield only 6 pupae on the first and zero on the subsequent collections. The results suggested that SIT proved successful in Naoway islet. For Guimaras, an island-wide implementation of SIT could be undertaken after reducing the wild male fruit fly population by field sanitation and the male annihilation method in order to overflood the wild population with sterile fruit flies. (Author)

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→ V_τ 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.

Radio-induced inherited sterility in Heliothis zea (Boddie)

International Nuclear Information System (INIS)

Carpenter, J.E.

1985-01-01

Heliothis zea (Boddie) (Lepidoptera: Noctuidae) males and females were irradiated with substerilizing doses of radiation. These moths were inbred and outcrossed and observed for their ability to reproduce. The inherited deleterious effects resulting from the irradiated P 1 males were recorded for several generations. Larvae from both irradiated (10 krad) and normal parents were compared for their ability to survive under field conditions on whole-stage sweet corn and these results were compared with those from a laboratory study using meridic diet. Irradiated males and females and F 1 males from an irradiated (10 krad) male x normal female cross were released in the field and in field cages and observed for their ability to search/attract and secure a mate. Females that had mated with normal and irradiated (10 krad) males were studied to determine the effect of different mating histories on the subsequent mating propensity of the females. A 10-krad dose of radiation induced deleterious effects which were inherited through the F 2 generation. These radiation-induced deleterious effects were similar to those reported in other species of Lepidoptera. The relationship between the survival of normal larvae and larvae from irradiated parents was similar under laboratory and field rearing conditions. Females mated to normal males and males irradiated with 10 krad had the same mating propensity and experienced the same intermating interval. These effects of substerilizing doses of radiation and inherited sterility on the reproductive ability and behavior of H. zea suggest that a great potential exists for population suppression

Mating competitiveness of irradiated males and females of the indian meal moth (Lepidoptera: Pyralidae)

International Nuclear Information System (INIS)

Brower, J.H.

1978-01-01

One-day-old adults of the Indian meal moth, Plodia interpunctella (Huebner), were irradiated (I) with either 35 krad (a partially sterilizing dose) or 50 krad (a sterilizing dose) and combined with untreated (U) adults at numbers of 1, 5, 10, 15, or 25 treated males or females per pair of untreated adults. At 25 males per pair, egg hatch was reduced to 4.8 and 22.2% at 35 and 50 krad, respectively. The calculated degree of competitiveness showed that both males and females were more competitive after treatment with 35 krad than after treatment with 50 krad and that treated females were more competitive (based on percentage egg hatch) at both doses than corresponding males. Irradiated females were fully competitive at most release ratios, but I males were not fully competitive even at the higher release ratios, although the decreases were not large enough to seriously affect their use for field control. (author)

Life history evolution in social insects : A female perspective

NARCIS (Netherlands)

Negroni, Matteo Antoine; Jongepier, Evelien; Feldmeyer, Barbara; Kramer, Boris H.; Foitzik, Susanne

2016-01-01

Social insects are known for their unusual life histories with fecund, long-lived queens and sterile, short-lived workers. We review ultimate factors underlying variation in life history strategies in female social insects, whose social life reshapes common trade-offs, such as the one between

Partial pine sterility in 1986 and 1987 within the zone of Chernobyl accident

International Nuclear Information System (INIS)

Khromova, L.V.; Romanovskij, M.G.; Dukharev, V.A.

1990-01-01

Reproductive potency of Pinus silvestris was studied in 1986 and 1987 within the zone of Chernobyl accident by the estimates of the survival rate of seed-buds during the gametophyte and embryonal development. At the radiation level of 4 Gy a partial female pine sterility was manifested by the decreased gametophyte survival rate of seedbuds, pollinated in 1986, and by the diminished embryonal survival rate of seed-buds pollinated in 1985

When Eggs Don't Hatch. The Benefits of the Sterile Insect Technique

International Nuclear Information System (INIS)

Kilian, Lizette

2012-01-01

Insect pests, such as the medfly, tsetse flies and carob moth can devastate crops and infect herds, causing severe economic hardship. To suppress the insect pest population and protect their livestock and crops, farmers usually use large quantities of pesticides. However, these pesticides are expensive, a risk to public health and cause environmental damage. Another technique, however, can reduce the insect pest population using natural means that do not require toxic chemicals: the sterile insect technique, or SIT. When female insect pests mate with male partners that have been radiation sterilized, the insemination produces eggs that cannot hatch. Since mating does not produce offspring, the insect population decreases naturally. The pest population can be suppressed with little or no use of pesticides. With the help of the IAEA, farmers have applied SIT successfully in over 20 countries on five continents, for over 15 insect species worldwide.

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

Dominance of sterilization and alternative choices of contraception in India: an appraisal of the socioeconomic impact.

Directory of Open Access Journals (Sweden)

Isabel Tiago de Oliveira

Full Text Available BACKGROUND: The recent decline in fertility in India has been unprecedented especially in southern India, where fertility is almost exclusively controlled by means of permanent contraceptive methods, mainly female sterilization, which constitutes about two-thirds of overall contraceptive use. Many Indian women undergo sterilization at relatively young ages as a consequence of early marriage and childbearing in short birth intervals. This research aims to investigate the socioeconomic factors determining the choices for alternative contraceptive choices against the dominant preference for sterilization among married women in India. METHODS: Data for this study are drawn from the 2005-06 National Family Health Surveys focusing on a sample of married women who reported having used a method of contraception in the five years preceding the survey. A multilevel multinomial logit regression is used to estimate the impact of socioeconomic factors on contraceptive choices, differentiating temporary modern or traditional methods versus sterilization. FINDINGS: Religious affiliation, women's education and occupation had overarching influence on method choices amongst recent users. Muslim women were at higher odds of choosing a traditional or modern temporary method than sterilization. Higher level of women's education increased the odds of modern temporary method choices but the education effect on traditional method choices was only marginally significant. Recent users belonging to wealthier households had higher odds of choosing modern methods over sterilization. Exposure to family planning messages through radio had a positive effect on modern and traditional method choices. Community variations in method choices were highly significant. CONCLUSION: The persistent dominance of sterilization in the Indian family planning programme is largely determined by socioeconomic conditions. Reproductive health programmes should address the socioeconomic barriers

Dominance of sterilization and alternative choices of contraception in India: an appraisal of the socioeconomic impact.

Science.gov (United States)

de Oliveira, Isabel Tiago; Dias, José G; Padmadas, Sabu S

2014-01-01

The recent decline in fertility in India has been unprecedented especially in southern India, where fertility is almost exclusively controlled by means of permanent contraceptive methods, mainly female sterilization, which constitutes about two-thirds of overall contraceptive use. Many Indian women undergo sterilization at relatively young ages as a consequence of early marriage and childbearing in short birth intervals. This research aims to investigate the socioeconomic factors determining the choices for alternative contraceptive choices against the dominant preference for sterilization among married women in India. Data for this study are drawn from the 2005-06 National Family Health Surveys focusing on a sample of married women who reported having used a method of contraception in the five years preceding the survey. A multilevel multinomial logit regression is used to estimate the impact of socioeconomic factors on contraceptive choices, differentiating temporary modern or traditional methods versus sterilization. Religious affiliation, women's education and occupation had overarching influence on method choices amongst recent users. Muslim women were at higher odds of choosing a traditional or modern temporary method than sterilization. Higher level of women's education increased the odds of modern temporary method choices but the education effect on traditional method choices was only marginally significant. Recent users belonging to wealthier households had higher odds of choosing modern methods over sterilization. Exposure to family planning messages through radio had a positive effect on modern and traditional method choices. Community variations in method choices were highly significant. The persistent dominance of sterilization in the Indian family planning programme is largely determined by socioeconomic conditions. Reproductive health programmes should address the socioeconomic barriers and consider multiple cost-effective strategies such as mass

[Emotional consequences of sterilization. Clinical comments on the methodology of psychological studies].

Science.gov (United States)

Petersen, P

1983-04-01

72 detailed psychiatric and psychological retrospective and prospective investigations (from 1928-1975) on the emotional consequences of male and female sterilization were reviewed and the international literature is summarized. Favorable conditions for sterilization are clear and decisive motivation, freedom of decision making, throrough understanding of the decision of the sexual partner, a harmonious relationship with that partner, a stable and sensitive personality, and thorough preoperative individual counseling. Integration of the procedure may take from 1-4 years and occurs in both partners. This is a dynamic process which brings with it a crisis during which the disturbance may be integrated. Consequently, surgical contraception is a challenge to the relationship of the partners. Investigations to date point to coveted motivation. Personal ambition of the investigator, justification for the operation, political motives in favor of widespread surgical sterilization, and pragmatic clinical motives are often found. Rarely is the motive in the investigation the mere search for scientific truth. Frequently, perfectionistic objectivisim and positivism are found and the subjectivity of the investigator and client is eliminated. In future investigations, the transparency in the relationship of the investigator and client and anthropological concepts should be considered. Part of the investigation must consider transcultural comparisons in the significance of liberty, love, and loyality in reproduction and family planning. (author's)

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)

Sterilization of heparinized cuprophan hemodialysis membranes

OpenAIRE

ten Hoopen, Hermina W.M.; Hinrichs, W.L.J.; Hinrichs, W.L.J.; Engbers, G.H.M.; Feijen, Jan

1996-01-01

The effects of sterilization of dry heparinized Cuprophan hemodialysis membranes by means of ethylene oxide (EtO) exposure, gamma irradiation, or steam on the anticoagulant activity and chemical characteristics of immobilized heparin and the permeability of the membrane were investigated. Sterilization did not result in a release of heparin or heparin fragments from heparinized Cuprophan. Sterilization of heparinized Cuprophan by means of EtO exposure and gamma irradiation induced a slight, i...

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

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

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

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

Hybrid male sterility between the fresh- and brackish-water types of ninespine stickleback Pungitius pungitius (Pisces, Gasterosteidae).

Science.gov (United States)

Takahashi, Hiroshi; Nagai, Terumi; Goto, Akira

2005-01-01

Two ecologically distinct forms, fresh- and brackish-water types, of ninespine stickleback co-exist in several freshwater systems on the coast of eastern Hokkaido. Recent genetic analyses of 13 allozyme loci revealed genetic separation between the two types even though their spawning grounds were in close proximity. On the other hand, there is only a small difference in mitochondrial DNA (mtDNA) sequence between the two types suggesting that they diverged quite recently or that mtDNA introgression occurred between them. To test for postzygotic reproductive isolating mechanisms and hybrid mediated gene flow, we examined the viability and reproductive performance of reciprocal F1 hybrids. The hybrids grew to the adult size normally and both sexes expressed secondary sexual characters in the reciprocal crosses. The female hybrids were reciprocally fertile, while the male hybrids were reciprocally sterile. Histological and flow-cytometric analyses of the hybrid testis revealed that the sterility pattern was classified as 'gametic sterility,' with gonads of normal size but abnormal spermatogenesis. To our knowledge, the present finding is a novel example of one sex hybrid sterility in the stickleback family (Gasterosteidae).

Genetic dissection of hybrid incompatibilities between Drosophila simulans and D. mauritiana. I. Differential accumulation of hybrid male sterility effects on the X and autosomes.

Science.gov (United States)

Tao, Yun; Chen, Sining; Hartl, Daniel L; Laurie, Cathy C

2003-08-01

The genetic basis of hybrid incompatibility in crosses between Drosophila mauritiana and D. simulans was investigated to gain insight into the evolutionary mechanisms of speciation. In this study, segments of the D. mauritiana third chromosome were introgressed into a D. simulans genetic background and tested as homozygotes for viability, male fertility, and female fertility. The entire third chromosome was covered with partially overlapping segments. Many segments were male sterile, while none were female sterile or lethal, confirming previous reports of the rapid evolution of hybrid male sterility (HMS). A statistical model was developed to quantify the HMS accumulation. In comparison with previous work on the X chromosome, we estimate that the X has approximately 2.5 times the density of HMS factors as the autosomes. We also estimate that the whole genome contains approximately 15 HMS "equivalents"-i.e., 15 times the minimum number of incompatibility factors necessary to cause complete sterility. Although some caveats for the quantitative estimate of a 2.5-fold density difference are described, this study supports the notion that the X chromosome plays a special role in the evolution of reproductive isolation. Possible mechanisms of a "large X" effect include selective fixation of new mutations that are recessive or partially recessive and the evolution of sex-ratio distortion systems.

The development of radiation-induced sterility for the management of lepidopterous maize stem bores:El dana saccharina walker (pyraldae) and sesmia calamistis hampson (noctuidae)

International Nuclear Information System (INIS)

Annoh, C. E

2003-01-01

Radio-sterilization study was conducted on the biology of two lepidopterous maize stem borers, Eldana saccharina Walker and Sesamia calamistis Hampson to induce inherited sterility for insect pest management programme in Ghana. Bioecology of the two borer species was also studied for a 3-year period, 1997-1999 at Medie, a predominantly maize growing community in the Ga District of Greater Accra Region, to determine the population dynamics and climatic factors influencing the population of the borer species. It was observed that Sesamia species usually attacked the young maize crop, with peak infestations occurring about 6-S weeks after emergence of the crop. Eldana species preferred mature maize with peak infestations around 10-12 weeks after emergence of the maize crop. Larval numbers of E. saccharina showed inverse relations with rainfall, r= - 0.5899; p= 0.043. Infestation levels of larvae of both species were relatively higher during the minor rainy season than the major season. Larvae and pupae of E. saccharina that developed separately on natural and artificial diets did not show significant difference in most of their biological parameters. In both borer species, pupal weights of natural dieters were slightly heavier than those of artificial dieters. Exposure of young pupae (less than 6 days old) of the two borer species to increasing doses of ionizing radiation, SO-ISO Gy, resulted in high percentage of deformity and un emerged adults. Mature pupae of 6-S days old were less susceptible to increased doses and exhibited fewer body deformities and unemerged adults. The mating capability of adults emerged from irradiated mature pupae of E. saccharina was not adversely affected. In the parent generation (P), fecundity and fertility decreased with increased doses of radiation for crosses involving irradiated males and normal females as well as irradiated females and normal males. While the treatment m the former crosses resulted in partial fertility (40% at 180

Pre-sterilization contamination of disposable medical products and the choice of minimum sterilization dose

International Nuclear Information System (INIS)

Horakova, V.; Buriankova, E.

1975-01-01

The bacterial contamination was assessed on randomly taken samples of blood-transfusion devices, donor sets, intra-uterine contraceptive devices and inserters, surgical gloves and dressing material prior to sterilization. The quantitative and qualitative efficiency of six nutrient media was compared. The best results were obtained with the enriched ''Universal'' medium. It was confirmed that the contamination of plastic products was low compared with dressing material. Most frequently, Gram-positive aerobic spore-forming rods and Gram-positive cocci were found on non-sterile medical disposable products. A method was tested to obtain a general informative picture of the resistance of bacteria on products. The methods used for choosing the dose for radiation sterilization of medical products are discussed. (author)

Hysteroscopic tubal sterilization: a health economic literature review.

Science.gov (United States)

2013-01-01

Hysteroscopic sterilization is a minimally invasive alternative to laparoscopic tubal ligation for women who want permanent contraception. In contrast to the laparoscopic technique, a hysteroscope is used to pass permanent microinserts through the cervix and place them in the fallopian tubes. This procedure does not require local or general anesthesia and can be performed in an office setting. The objective of this analysis was to determine, based on published literature, the cost-effectiveness of hysteroscopic tubal sterilization (HS) compared with laparoscopic tubal ligation (LS) for permanent female sterilization. A systematic literature search was conducted for studies published between January 1, 2008, and December 11, 2012. Potentially relevant studies were identified based on the title and abstract. Cost-utility analyses (studies that report outcomes in terms of costs and quality-adjusted life-years) were prioritized for inclusion. When not available, cost-effectiveness, cost-benefit, and cost-consequence analyses were considered. Costing studies were considered in the absence of all other analyses. A total of 33 abstracts were identified. Three cost analyses were included. A retrospective chart review from Canada found that HS was $111 less costly than LS; a prospective activity-based cost management study from Italy reported that it was €337 less costly than LS; and the results of an American decision model showed that HS was $1,178 less costly than LS. All studies had limited applicability to the Ontario health care system due to differences in setting, resource use, and costs. Three cost analyses found that, although the HS procedure was more expensive due to the cost of the microinserts, HS was less costly than LS overall due to the shorter recovery time required. Hysteroscopic sterilization is a minimally invasive alternative to conventional tubal ligation for women who want a permanent method of contraception. Both approaches involve closing off the

Heat or gamma irradiation sterilization affects the hypocholesterolemic effect of guar gum in axenic and heteroxenic rats

International Nuclear Information System (INIS)

Alvarez-Leite, J.I.; Vieira, E.C.; Andrieux, C.

1994-01-01

Twenty-two axenic (germ free) or thirty heteroxenic (axenic colonized with human flora) 2.5-3.5 months old female Fisher rats were fed for four weeks either a hypercholesterolemic (hyper) diet or a hyper diet containing 5% guar gum (GG) sterilized by heat or gamma radiation. Axenic s rat fed the irradiated GG diet had had high cholesterolemia than their counterparts fed in autoclave diet (4.50 vs 2.29 mmol/l), whereas the method of sterilization had no effect on plasma cholesterol on axenic hyper or heteroxenic animals fed (7.35 vs 6.51 mg/dl). The levels of hepatic esterified cholesterol were higher in heteroxenic animals fed the irradiated GG diet than in their counterparts fed the autoclave GG diet (5.65 vs 3.57 mmol/g tissue). The composition of volatile fatty acids in the cecal contents of heteroxenic rats was dependent on the method of sterilization regardless of the presence of fiber: the levels of butyrate were 2.88 and 0,85 μmol/g for rats fed the autoclave and irradiated diets, respectively. Gamma radiation abolished the cholesterol-lowering effect of guar gum, whereas sterilization by heat preserved this effect. The hypocholesterolemic effect of guar was reduced by gamma irradiation sterilization and was probably mediated by qualitative changes in the intestinal microflora which interfered with bile acid absorption. (author)

Simulating sterilization, vaccination, and test-and-remove as brucellosis control measures in bison

Science.gov (United States)

Ebinger, M.; Cross, P.; Wallen, Rick; White, P.J.; Treanor, John

2011-01-01

Brucella abortus, the causative agent of bovine brucellosis, infects wildlife, cattle, and humans worldwide, but management of the disease is often hindered by the logistics of controlling its prevalence in wildlife reservoirs. We used an individually based epidemiological model to assess the relative efficacies of three management interventions (sterilization, vaccination, and test-and-remove). The model was parameterized with demographic and epidemiological data from bison in Yellowstone National Park, USA. Sterilization and test-and-remove were most successful at reducing seroprevalence when they were targeted at young seropositive animals, which are the most likely age and sex category to be infectious. However, these approaches also required the most effort to implement. Vaccination was less effective (even with a perfect vaccine) but also required less effort to implement. For the treatment efforts we explored (50–100 individuals per year or 2.5–5% of the female population), sterilization had little impact upon the bison population growth rate when selectively applied. The population growth rate usually increased by year 25 due to the reduced number of Brucella-induced abortions. Initial declines in seroprevalence followed by rapid increases (>15% increase in 5 years) occurred in 3–13% of simulations with sterilization and test-and-remove, but not vaccination. We believe this is due to the interaction of superspreading events and the loss of herd immunity in the later stages of control efforts as disease prevalence declines. Sterilization provided a mechanism for achieving large disease reductions while simultaneously limiting population growth, which may be advantageous in some management scenarios. However, the field effort required to find the small segment of the population that is infectious rather than susceptible or recovered will likely limit the utility of this approach in many free-ranging wildlife populations. Nevertheless, we encourage

Sowing the seeds of economic entomology: houseflies and the emergence of medical entomology in Britain.

Science.gov (United States)

Clark, J F M

2008-12-01

The golden age of medical entomology, 1870-1920, is often celebrated for the elucidation of the aetiology of vector-borne diseases within the rubric of the emergent discipline of tropical medicine. Within these triumphal accounts, the origins of vector control science and technology remain curiously underexplored; yet vector control and eradication constituted the basis of the entomologists' expertise within the emergent specialism of medical entomology. New imperial historians have been sensitive to the ideological implications of vector control policies in the colonies and protectorates, but the reciprocal transfer of vector-control knowledge, practices and policies between periphery and core have received little attention. This paper argues that medical entomology arose in Britain as an amalgam of tropical medicine and agricultural entomology under the umbrella of "economic entomology". An examination of early twentieth-century anti-housefly campaigns sheds light on the relative importance of medical entomology as an imperial science for the careers, practices, and policies of economic entomologists working in Britain. Moreover, their sensitivity to vector ecology provides insight into late nineteenth- and early twentieth-century urban environments and environmental conditions of front-line war.

Standardized Method for High-throughput Sterilization of Arabidopsis Seeds.

Science.gov (United States)

Lindsey, Benson E; Rivero, Luz; Calhoun, Chistopher S; Grotewold, Erich; Brkljacic, Jelena

2017-10-17

Arabidopsis thaliana (Arabidopsis) seedlings often need to be grown on sterile media. This requires prior seed sterilization to prevent the growth of microbial contaminants present on the seed surface. Currently, Arabidopsis seeds are sterilized using two distinct sterilization techniques in conditions that differ slightly between labs and have not been standardized, often resulting in only partially effective sterilization or in excessive seed mortality. Most of these methods are also not easily scalable to a large number of seed lines of diverse genotypes. As technologies for high-throughput analysis of Arabidopsis continue to proliferate, standardized techniques for sterilizing large numbers of seeds of different genotypes are becoming essential for conducting these types of experiments. The response of a number of Arabidopsis lines to two different sterilization techniques was evaluated based on seed germination rate and the level of seed contamination with microbes and other pathogens. The treatments included different concentrations of sterilizing agents and times of exposure, combined to determine optimal conditions for Arabidopsis seed sterilization. Optimized protocols have been developed for two different sterilization methods: bleach (liquid-phase) and chlorine (Cl2) gas (vapor-phase), both resulting in high seed germination rates and minimal microbial contamination. The utility of these protocols was illustrated through the testing of both wild type and mutant seeds with a range of germination potentials. Our results show that seeds can be effectively sterilized using either method without excessive seed mortality, although detrimental effects of sterilization were observed for seeds with lower than optimal germination potential. In addition, an equation was developed to enable researchers to apply the standardized chlorine gas sterilization conditions to airtight containers of different sizes. The protocols described here allow easy, efficient, and

Transcriptomic profiling of gametogenesis in triploid Pacific Oysters Crassostrea gigas: towards an understanding of partial sterility associated with triploidy.

Directory of Open Access Journals (Sweden)

Nolwenn M Dheilly

Full Text Available Triploidy can occur in many animal species but is often lethal. Among invertebrates, amphibians and fishes, triploids are viable although often sterile or infertile. Most triploids of the Pacific oyster Crassostrea gigas are almost sterile (named "3nβ" yet a low but significant proportion show an advanced gametogenesis (named "3nα". These oysters thus constitute an interesting model to study the effect of triploidy on germ cell development. We used microarrays to compare the gonad transcriptomes of diploid 2n and the abovementioned triploid 3nβ and 3nα male and female oysters throughout gametogenesis.All triploids displayed an upregulation of genes related to DNA repair and apoptosis and a downregulation of genes associated with cell division. The comparison of 3nα and 3nβ transcriptomes with 2n revealed the likely involvement of a cell cycle checkpoint during mitosis in the successful but delayed development of gonads in 3nα individuals. In contrast, a disruption of sex differentiation mechanisms may explain the sterility of 3nβ individuals with 3nβ females expressing male-specific genes and 3nβ males expressing female-specific genes.The disruption of sex differentiation and mitosis may be responsible for the impaired gametogenesis of triploid Pacific oysters. The function of the numerous candidate genes identified in our study should now be studied in detail in order to elucidate their role in sex determination, mitosis/meiosis control, pachytene cell cycle checkpoint, and the control of DNA repair/apoptosis.

Sterile neutrinos as dark matter

International Nuclear Information System (INIS)

Dodelson, S.; Widrow, L.M.

1994-01-01

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

Exploiting novel sterilization techniques for porous polyurethane scaffolds.

Science.gov (United States)

Bertoldi, Serena; Farè, Silvia; Haugen, Håvard Jostein; Tanzi, Maria Cristina

2015-05-01

Porous polyurethane (PU) structures raise increasing interest as scaffolds in tissue engineering applications. Understanding the effects of sterilization on their properties is mandatory to assess their potential use in the clinical practice. The aim of this work is the evaluation of the effects of two innovative sterilization techniques (i.e. plasma, Sterrad(®) system, and ozone) on the morphological, chemico-physical and mechanical properties of a PU foam synthesized by gas foaming, using water as expanding agent. In addition, possible toxic effects of the sterilization were evaluated by in vitro cytotoxicity tests. Plasma sterilization did not affect the morphological and mechanical properties of the PU foam, but caused at some extent degradative phenomena, as detected by infrared spectroscopy. Ozone sterilization had a major effect on foam morphology, causing the formation of new small pores, and stronger degradation and oxidation on the structure of the material. These modifications affected the mechanical properties of the sterilized PU foam too. Even though, no cytotoxic effects were observed after both plasma and ozone sterilization, as confirmed by the good values of cell viability assessed by Alamar Blue assay. The results here obtained can help in understanding the effects of sterilization procedures on porous polymeric scaffolds, and how the scaffold morphology, in particular porosity, can influence the effects of sterilization, and viceversa.

Application of radiation sterilization to bone allografts

International Nuclear Information System (INIS)

Li Youchen; Li Baoxing; Sun Shiquan

2003-01-01

With prominent features of high penetration, no temperature increases, no harm residues and easy dose control, radiation sterilization technology is widely used in the sterilization of bone allografts. During the radiation sterilization of bone allografts, the irradiation dose should be optimized to ensure sterilization of grafts and preservation of biological properties of bone. The immunogenicity of allografts is decreased by irradiation. IAEA devoted great efforts to generalization of the radiation sterilization of tissue allografts in developing countries since 1986. Tissue Bank of China Institute for Radiation Protection (CIRP) was initially established in 1988 with the support of IAEA, afterwards restructured into Shanxi Provincial Tissue Bank (SPTB). The SPTB, as the first manufacturer of the irradiated bone allografts in the country, was granted production license by the State Food and Drug Administration of China. The SPTB sponsored IAEA/RCA Training Courses, National Symposium on Bone Grafting, and National Training Course on Bone Banking. Technique of radiation sterilization for bone grafts has become popularized in China after these activities. (authors)

Radiation sterilization of some pharmaceutical preparations and medical products

International Nuclear Information System (INIS)

Tashmetov, M.Yu.; Makhkamov, Sh.M.; Urinov, Sh.S.; Turaev, A.S.; Sultanov, M.S.; Inagomov, Kh.S.

2006-01-01

Full text: In connection with intensive development of pharmacology and medical techniques, use of the products contacting to blood, with the internal environment of an organism, with wound surface, with mucous membranes and skin there were high requirements to sterility of pharmaceutical preparations and medical products. Traditional methods of sterilization (heat treatment, gas processing and processing the ferry) have some restrictions in application, and not insufficient degree of sterilization required for pharmaceutical preparations and medical products. Thermal processing can lead to degradation of structure (medicine), mechanical changes and loss of medical properties. Besides, it is impossible to carry out sterilization of many pharmaceutical preparations by a method of heat treatment. Sterilization of products in packing is very complicated, because sterilization temperature of packing and a product is different. Gas processing is basically applied to sterilization of medical products (syringes, bandage, cotton wools, etc.). However, the degree of sterility is low, because of rather low ability and heterogeneity of sterilizing substance. Sterilization in packing represents special difficulty and demands additional charges related with delivery of the purified gas from abroad. Last years alongside with known technological methods of sterilization of medical products and pharmaceutical preparations radiating methods of processing have found wide application. Use of electronic bunches with the moderate energy and various isotopes became a basis for formation and development of a new direction in the medicine, called by 'radiation sterilization'. The radiation technology is highly harmless and economic, not polluting substance and surrounding space. Unlike the specified traditional methods, radiating processing of products by the isotope 60 Co, radiating the gamma quantum, has unique opportunities - high penetrability in substance, providing uniformity of

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

Science.gov (United States)

Vyskocilová, Martina; Prazanová, Gabriela; Piálek, Jaroslav

2009-02-01

The hybrid sterility-1 (Hst1) locus at Chr 17 causes male sterility in crosses between the house mouse subspecies Mus musculus domesticus (Mmd) and M. m. musculus (Mmm). This locus has been defined by its polymorphic variants in two laboratory strains (Mmd genome) when mated to PWD/Ph mice (Mmm genome): C57BL/10 (carrying the sterile allele) and C3H (fertile allele). The occurrence of sterile and/or fertile (wild Mmm x C57BL)F1 males is evidence that polymorphism for this trait also exists in natural populations of Mmm; however, the nature of this polymorphism remains unclear. Therefore, we derived two wild-origin Mmm strains, STUS and STUF, that produce sterile and fertile males, respectively, in crosses with C57BL mice. To determine the genetic basis underlying male fertility, the (STUS x STUF)F1 females were mated to C57BL/10 J males. About one-third of resulting hybrid males (33.8%) had a significantly smaller epididymis and testes than parental animals and lacked spermatozoa due to meiotic arrest. A further one-fifth of males (20.3%) also had anomalous reproductive traits but produced some spermatozoa. The remaining fertile males (45.9%) displayed no deviation from values found in parental individuals. QTL analysis of the progeny revealed strong associations of male fitness components with the proximal end of Chr 17, and a significant effect of the central section of Chr X on testes mass. The data suggest that genetic incompatibilities associated with male sterility have evolved independently at the proximal end of Chr 17 and are polymorphic within both Mmd and Mmm genomes.

Inherited sterility in progeny of irradiated male cotton leafworm, spodoptera littoralis (boisd)

International Nuclear Information System (INIS)

Sallam, H.A.

1991-01-01

Full grown male pupae of spodoptera littoralis were exposed to sub sterilizing doses of 7.5, 10, 12.5 or 15 krad of gamma radiation and mated with unirradiated females. In another trial, male pupae irradiated with 10 krad were crossed with unirradiated females, and their progeny were out crossed or inbred. In all cases, the effects of these treatments on some biological aspects in the resulting progeny for 3 generations were studied. Larval and pupal mortality were 21 to 53% and 5 to 30% higher than the normal among F 1 and F 2 , respectively. THE average developmental time from egg hatch to adult emergence was not affected and so, also sex ratio which seemed about normal.2 tab

Inherited sterility in progeny of irradiated male cotton leafworm, spodoptera littoralis (boisd)

Energy Technology Data Exchange (ETDEWEB)

Sallam, H A

1991-01-01

Full grown male pupae of spodoptera littoralis were exposed to sub sterilizing doses of 7.5, 10, 12.5 or 15 krad of gamma radiation and mated with unirradiated females. In another trial, male pupae irradiated with 10 krad were crossed with unirradiated females, and their progeny were out crossed or inbred. In all cases, the effects of these treatments on some biological aspects in the resulting progeny for 3 generations were studied. Larval and pupal mortality were 21 to 53% and 5 to 30% higher than the normal among F[sub 1] and F[sub 2], respectively. THE average developmental time from egg hatch to adult emergence was not affected and so, also sex ratio which seemed about normal.2 tab.

Sterilization of Hulecoeteomyia japonica japonica (=Aedes japonicus japonicus) (Theobald, 1901) by high-energy photon irradiation: implications for a sterile insect technique approach in Europe

International Nuclear Information System (INIS)

Balestrino, F.; Mathis, A.; Veronesi, E.; Lang, S.

2017-01-01

Hulecoeteomyia japonica japonica (=Aedes japonicus japonicus) (Diptera: Culicidae) (Theobald 1901), a container breeding invasive species in North America and Europe, is attracting particular attention for its high local abundances and possible roles in the transmission of human and animal pathogens. The preferential habitats of this species are forested and bushy areas, which renders control measures extremely inefficient. Use of the sterile insect technique (SIT) may contribute to the implementation of area-wide integrated pest management strategies, as has been successfully proven with other aedine mosquito species. The present study investigates the effects of irradiation at a dose of 40 Gy on fitness parameters in H. j. japonica. Irradiation was performed on 16–24- h-old pupae from a colonized strain (PA) using a True- Beam linear accelerator. Males from the PA strain were crossed with females of the same colony or with field-collected females. Irradiation induced a slight increase in mortality in male pupae, but did not alter the survival and mating abilities of emerging adult males. Rates of blood feeding and fertility were lower when PA strain males were kept with field-collected females rather than PA females. Irradiated males induced reductions in fertility (residual fertility: 2.6%) and fecundity in mated females. The data indicate that the SIT is a suitable technique to enhance the control of this species. (author)

EPR STUDIES OF THERMALLY STERILIZED VASELINUM ALBUM.

Science.gov (United States)

Ramos, Paweł; Pilawa, Barbara

2015-01-01

Electron paramagnetic resonance (EPR) spectroscopy was used for examination of free radicals in thermally treated vaselinum album (VA). Thermal treatment in hot air as sterilization process was tested. Conditions of thermal sterilization were chosen according to the pharmaceutical norms. Vaselinum album was heated at the following conditions (T--temperature, t--time): T = 160°C and t = 120 min, T = 170°C and t = 60 min and T = 180°C and t = 30 min. The aim of this work was to determine concentration and free radical properties of thermally sterilized VA. EPR analysis for VA was done 15 min after sterilization. EPR measurements were done at room temperature. EPR spectra were recorded in the range of microwave power of 2.2-70 mW. g-Factor, amplitudes (A) and line width (ΔBpp) of the spectra were determined. The shape of the EPR spectra was analyzed. Free radical concentration (N) in the heated samples was determined. EPR spectra were not obtained for the non heated VA. EPR spectra were detected for all thermally sterilized samples. The spectra revealed complex character, their asymmetry depends on microwave power. The lowest free radicals concentration was found for the VA sterilized at 180°C during 30 min. EPR spectroscopy is proposed as the method useful for optimization of sterilization process of drugs.

[Determinants of sterilization among married couples in Korea].

Science.gov (United States)

Kim, Ju Hee; Chung, Woojin; Lee, Sunmi; Suh, Moonhee; Kang, Dae Ryong

2007-11-01

The purpose of this study was to examine the determinants of sterilization in South Korea. This study was based on the data from the Korea National Fertility Survey carried out in the year 2000 by the Korea Institute of Health and Social Affairs. The subjects of the analysis were 4,604 women and their husbands who were in their first marriage, in the age group of 15-49 years. The data were analyzed by multiple logistic regression analysis. Consistent with the findings of previous studies, the woman's age and the number of total children increased the likelihood of sterilization. In addition, the year of marriage had a strong positive association with sterilization. Interestingly, the number of surviving sons tended to increase the likelihood of sterilization, whereas the woman's education level and age at the time of marriage showed a negative association with sterilization. Religion, place of residence, son preference, and the husband's education level, age and type of occupation were not significant determinants of sterilization. The sex of previous children and lower level of education are distinct determinants of sterilization among women in South Korea. More studies are needed in order to determine the associations between sterilization rate and decreased fertility.

Studies on induced mutation of sesame male sterility

International Nuclear Information System (INIS)

Li Yingde; Feng Xiangyun; Zhao Yingzhong

2001-01-01

The dry seeds of the high yielding cultivar, Yuzhi-4, were irradiated with 300, 500 and 700 Gy of 60 Co- gamma rays. 3277 M 1 plants were harvested separately as single plants and also in bulk, by doses. In M 2 , the single plant seeds were grown in progeny rows and the bulked seeds were grown as bulks. 25 male sterile plants were screened from M 2 . 10 of the 25 male sterile plants were from the progenies of the single plant seeds and 15 were from the progenies of the bulked seeds. In further genetic research of the 25 male sterile plants in M 3 and M 4 , 6 separate genic male sterile (GMS) lines were identified. Their male sterility was stable and was controlled by a pair of alleles, male fertility being dominant to sterility. (author)

A see-saw mechanism with light sterile neutrinos

International Nuclear Information System (INIS)

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

2001-01-01

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

Cosmology seeking friendship with sterile neutrinos

International Nuclear Information System (INIS)

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

2011-01-01

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

Sterilization of solutions for parenterals products. Problem analysis

Directory of Open Access Journals (Sweden)

Yanelys Montes-González

2017-09-01

Full Text Available The solutions for the formulation of parenteral products must be sterile before the aseptic formulation process. For this reason, different methods of sterilization referred in the literature are analyzed. Thermodynamic criteria that rule the sterilization are presented. Furthermore, previous experiences in the sterilization of solutions for the formulation of parental products in an autoclave are analyzed, that take large time of processing and only low volumes of solution can be handled. Using jacketed stirred tanks for the sterilization may solve the problem and, therefore, criteria for the design of the later that allow to process high volumes of solution for the formulation of parenteral products are shown.

A novel steam explosion sterilization improving solid-state fermentation performance.

Science.gov (United States)

Zhao, Zhi-Min; Wang, Lan; Chen, Hong-Zhang

2015-09-01

Traditional sterilization of solid medium (SM) requires lengthy time, degrades nutrients, and even sterilizes inadequately compared with that of liquid medium due to its low thermal conductivity. A novel sterilization strategy, high-temperature and short-time steam explosion (SE), was exploited for SM sterilization in this study. Results showed that SE conditions for complete sterilization were 172 °C for 2 min and 128 °C for 5 min. Glucose and xylose contents in medium after SE sterilization increased by 157% and 93% respectively compared with those after conventional sterilization (121 °C, 20 min) while fermentation inhibitors were not detected. FTIR spectra revealed that the mild SE conditions helped to release monosaccharides from the polysaccharides. Bacillus subtilis fermentation productivity on medium after SE sterilization was 3.83 times of that after conventional sterilization. Therefore, SE shortened sterilization time and improved SM nutrition, which facilitated fermentability of SM and should promote economy of solid-state fermentation. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

Sewage sterilization through gamma radiation

International Nuclear Information System (INIS)

Vieira, D.V.; Teixeira, W.M.S.; Silva, F.C.A. da

2017-01-01

Lack of sewage treatment and adequate sanitation conditions can contribute to the proliferation of numerous parasitic and infectious diseases in addition to water degradation. Approximately fifty types of infections can be transmitted from a sick to a healthy person through different pathways involving human excreta. Untreated sewage can contaminate water, food, hands, soil, etc. Epidemics of certain diseases such as typhoid, cholera, dysenteries, etc., and countless cases of worms are responsible for high mortality rates in third world countries. In the work the different techniques of sewage treatment by disinfestation and sterilization were analyzed, highlighting the use and the advantages of the gamma radiation as well as the aspects of the radiological protection involved. The technique of sewage sterilization using gamma radiation is a method of controlling bacteria and microorganisms. It is estimated that more than 200 large irradiators are in operation worldwide, of which 5 are in Brazil, for general sterilization use. These facilities use a large amount of radioactive material, in the order of millions of Becquerel, for sterilization with high doses of radiation, which can generate lethal doses in a few minutes. These industrial facilities use Cobalt-60, being classified by the International Atomic Energy Agency - IAEA as Category 1 of high risk, and must possess a high level of radiological protection to carry out the sterilization, standing out the defense in depth. Specific legislation on radiological protection should be drafted for safe work and avoid future radiation accidents

Searching for Sterile Neutrinos with MINOS

Energy Technology Data Exchange (ETDEWEB)

Timmons, Ashley [Manchester U.

2016-01-01

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

Ionizing radiation for sterilization of medical products and biological tissues

Energy Technology Data Exchange (ETDEWEB)

Kumar, S K; Raghevendrarao, M K [Bhabha Atomic Research Centre, Bombay (India). Library and Technical Information Section

1975-10-01

The article reviews the deliberations of the International Symposium on Ionizing Radiation for Sterilization of Medical Products and Biological Tissues which was held during 9-13 December 1974 under the auspices of the IAEA at the Bhabha Atomic Research Centre, Bombay. 42 papers were presented in the following broad subject areas: (1) Microbiological Control aspects of radiation sterilization, (2) Dosimetry aspects of radiation sterilization practices, (3) Effects of sterilizing radiation dose on the constituents of medical products, (4) Application of radiation sterilization of medical products of biological origin, (5) Technological aspects of radiation sterilization facilities, (6) Radiation sterilization of pharmaceutical substances, (7) Reports on current status of radiation sterilization of medical products in IAEA member states and (8) Working group discussion on the revision of the IAEA recommended code of practice for radiation sterilization of medical products.

Medfly female attractant trapping studies in Guatemala

International Nuclear Information System (INIS)

Jeronimo, F.; Rendon, P.; Villatoro, C.

1999-01-01

Experiments were conducted from 1994 - 1998 to test the attractiveness of combinations of food-based chemicals for C. capitata (medfly) in Guatemala. Most studies were done in coffee. The 1995 studies, using the FA-2 attractants (ammonium acetate and putrescine) showed that this combination was attractive for females and had potential for use in conjunction with a SIT program. The 1996 studies at three elevations demonstrated that, in general, these attractants, when used in either the Open Bottom Dry Trap (OBDT), Closed Bottom Dry Trap (CBDT), or International Pheromone's McPhail Trap (IPMT) performed better than the Jumbo McPhail trap (JMT) baited with NuLure and borax (NU+B) for capture of feral females. At the high elevation (1400 m), the IPMT with FA-2 and OBDT with FA-2 were best; at the middle elevation (1100 m), the ORDT, IPMT, and CBDT with FA-2 were best; and at low elevations (659 m), the IPMT with FA-2, JMT with NU+B and ORDT with FA-2 were equal in performance. At the middle elevation, using sterile flies, the OBDT with FA-2 worked best. When experiments were carried out in pear, the traps using the FA-2 attractants captured more female flies than the JMT, NU+B, but not significantly more. During the 1997 trials, a third component, trimethylamine was added to the two component lure (FA-3). This attractant was tested in a number of locally produced traps using 2 I soft drink bottles with different color bottoms. The dry versions of the traps contained a yellow sticky insert. All study sites were at low elevation 600 - 650 m, in coffee, testing both sterile and feral flies. With the feral flies during the first phase of the study at finca San Carlos, there were no significant differences between treatments, at finca San Luis, the clear local trap with sticky insert and the green local trap with sticky insert were best, and at finca Valapraiso, the green local trap with yellow sticky insert and yellow local trap with sticky insert captured more flies

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.

Effect of Gamma Irradiation on Male Sterilization and Structure of the Male Reproductive Accessory Glands of the Khapra Beetle Trogoderma Granarium Everts

International Nuclear Information System (INIS)

Abdel-Kawy, F.K.; El-Naggar, S.E.

2000-01-01

Changes in the male reproductive ability of Trogoderma Granarium Everts as regards to sterilization and structural changes in the accessory glands due to gamma radiation were studied. The reproductive ability of males irradiated as full grown pupae and mated with normal females was dose-dependent. A dose 100 Gy increased sterility of males to about 61.1%, while 200 Gy dose sterilized males completely. The number of eggs per mated female was significantly different from the control. The number of eggs decreased from 51.1 at 50 Gy to 5.9 at 200 Gy. Eclosion and deformity of males irradiated from 50 to 200 Gy seemed to be less affected as compared to the reproductive ability. When full grown male pupae were irradiated with the sterilizing dose, a considerable effect on the structure of accessory glands was observed. The dose 200 Gy caused lysis and damage of all type of secretory cells. The secretory epithelial cells showed abnormal appearance and became separated from each other. The cytoplasm was often shrunk, leaving spaces. The muscular sheaths surrounding the gland and lining its lumen were shrunk and damaged in some parts. The mitochondria and golgi bodies were completely lost. The multi microvilli lining the lumen of the gland disappeared. The basement membrane became loose and acquired irregular appearance in most parts. Intercellular microtubules disappeared completely. The gland generally was greatly damaged and lost its normal structure

9 CFR 116.4 - Sterilization and pasteurization -records.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Sterilization and pasteurization... REPORTS § 116.4 Sterilization and pasteurization -records. Records shall be made by means of automatic... ingredients, equipment, or biological product subjected to sterilization or pasteurization. (Approved by the...

Housefly maggot-treated composting as sustainable option for pig manure management.

Science.gov (United States)

Zhu, Feng-Xiang; Yao, Yan-Lai; Wang, Su-Juan; Du, Rong-Guang; Wang, Wei-Ping; Chen, Xiao-Yang; Hong, Chun-Lai; Qi, Bing; Xue, Zhi-Yong; Yang, Hong-Quan

2015-01-01

In traditional composting, large amounts of bulking agents must be added to reduce the moisture of pig manure, which increases the cost of composting and dilutes the N, P and K content in organic fertilizers. In this study, maggot treatment was used in composting instead of bulking agents. In experiment of selecting an optimal inoculum level for composting, the treatment of 0.5% maggot inoculum resulted in the maximum yield of late instar maggots, 11.6% (maggots weight/manure weight). The manure residue became noticeably granular by day 6 and its moisture content was below 60%, which was suitable for further composting without bulking agents. Moreover, in composting experiment with a natural compost without maggot inoculum and maggot-treated compost at 0.5% inoculum level, there were no significant differences in nutrient content between the two organic fertilizers from the two treatments (paired Student's t15=1.0032, P=0.3317). Therefore, maggot culturing did not affect the characteristics of the organic fertilizer. The content of TNPK (total nitrogen+total phosphorus+total potassium) in organic fertilizer from maggot treatment was 10.72% (dry weight), which was far more than that of organic fertilizer made by conventional composting with bulking agents (about 8.0%). Dried maggots as feed meet the national standard (GB/T19164-2003) for commercial fish meal in China, which contained 55.32 ± 1.09% protein; 1.34 ± 0.02% methionine; 4.15 ± 0.10% lysine. This study highlights housefly maggot-treated composting can be considered sustainable alternatives for pig manure management to achieve high-quality organic fertilizer and maggots as feed without bulking agents. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Preliminary Study of Lonicera hypoglauca on Germination Conditions of Sand Culture Seeds and Sterilization Method of Sand Culture Seedling Sterilization].

Science.gov (United States)

Tan, Mu-xiu; Zeng, Wen-wen; Wei, Peng-xiao; Mo, Qiao-cheng; Pu, Zu-ning; Cen, Xiu-fen; Shi, Feng-hua

2015-05-01

To explore the germination conditions of Lonicera hypoglauca sand culture seeds and the effects of sand culture seedlings sterilization. 0.1% HgCl2 with different sterilization time, different illumination time and temperature culture condition were adopted to study the germination conditions of sand culture seeds. Different sterilization treatments and different hardening-seedling days were used to test the sterilization effect of sand culture seedlings. The sterilization effect of the combination of 75% ethanol 30 s + 0.1% HgCl2 5 min on Lonicera hypoglauca seeds was the optimum,with the average pollution rate of 15.56%, and the average germination rate reached 51.11%. The combination of varied temperature-room temperature under light for 12 h/d was the best, with the average germination rate peaked at 75.49%, and the average germination potential reached 68.36%. The treatment of detergent liquor scrub-tap water wash on the part above the hypocotyl, which was sand cultured under the opening condition and had no root, showed the best sterilization effect, with the average pollution rate was zero, and the average survival rate peaked at 100.00%. The sterilization effect of sand culture seedlings, which was disinfected after cleaning by detergent liquor scrub-tap water wash after hardening-seeding for 30 days, was the best, with the average pollution rate of 50.00%, and the average survival rate of 100.00%. The best sterilization effect is the combination of 75% ethanol 30 s + 0.1% HgCl2 5 min; Lighting for 12 h/d of varied temperature-room temperature is regarded as the optimum culture condition. The treatment of detergent liquor scrub-tap water wash treatment on the part above the hypocotyl,which is sand cultured under the opening condition and had no root, shows the best sterilization effect. For the sand culture seedlings, before inoculated in subculture medium, should be hardening-seedling for some days and sterilized after detergent liquor scrub-tap water wash.

Ozone--the latest advance in sterilization of medical devices.

Science.gov (United States)

Murphy, Lorna

2006-06-01

How many times have procedures in your operating rooms been delayed because the instruments needed were still in the sterilizer? As Perioperative nurses you are likely to be quite familiar with the constant pressure to ensure that scarce instrumentation is available when needed. In 2003, a Canadian company developed a unique sterilization process employing ozone as the sterilizing agent. This technology is a safe, rapid and economical alternative to other low temperature sterilization modalities and may relieve some of the pressure experienced when instruments in short supply are in high demand. This article will discuss the principles of the sterilizer and the cycle and will explore the advantages of using this sterilization technology.

A Z-linked sterility locus causes sexual abstinence in hybrid females and facilitates speciation in Spodoptera frugiperda

Czech Academy of Sciences Publication Activity Database

Kost, S.; Heckel, D. G.; Yoshido, Atsuo; Marec, František; Groot, A. T.

2016-01-01

Roč. 70, č. 6 (2016), s. 1418-1427 ISSN 0014-3820 R&D Projects: GA ČR(CZ) GA14-22765S Grant - others:European Union Seventh Framework Programme (FP7/2007-2013)(CZ) 316304 Program:FP7 Institutional support: RVO:60077344 Keywords : hybrid sterility * sex chromosome * speciation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.201, year: 2016 http://onlinelibrary.wiley.com/doi/10.1111/evo.12940/abstract

Characterization and fine mapping of a female fertility associated ...

Indian Academy of Sciences (India)

2015-03-12

Mar 12, 2015 ... 1Key Laboratory of Agriculture Responding to Climate Change, Jiangxi ... Female-sterile line can be used as a pollinator which has a great potential for hybrid seeds production. ... Reciprocal crosses and pollen vitality assay suggest that the .... per plant, and seed-setting rate were investigated in ff1(t).

Allelic interaction of F1 pollen sterility loci and abnormal chromosome behaviour caused pollen sterility in intersubspecific autotetraploid rice hybrids.

Science.gov (United States)

He, J H; Shahid, M Q; Li, Y J; Guo, H B; Cheng, X A; Liu, X D; Lu, Y G

2011-08-01

The intersubspecific hybrids of autotetraploid rice has many features that increase rice yield, but lower seed set is a major hindrance in its utilization. Pollen sterility is one of the most important factors which cause intersubspecific hybrid sterility. The hybrids with greater variation in seed set were used to study how the F(1) pollen sterile loci (S-a, S-b, and S-c) interact with each other and how abnormal chromosome behaviour and allelic interaction of F(1) sterility loci affect pollen fertility and seed set of intersubspecific autotetraploid rice hybrids. The results showed that interaction between pollen sterility loci have significant effects on the pollen fertility of autotetraploid hybrids, and pollen fertility further decreased with an increase in the allelic interaction of F(1) pollen sterility loci. Abnormal ultra-structure and microtubule distribution patterns during pollen mother cell (PMC) meiosis were found in the hybrids with low pollen fertility in interphase and leptotene, suggesting that the effect-time of pollen sterility loci interaction was very early. There were highly significant differences in the number of quadrivalents and bivalents, and in chromosome configuration among all the hybrids, and quadrivalents decreased with an increase in the seed set of autotetraploid hybrids. Many different kinds of chromosomal abnormalities, such as chromosome straggling, chromosome lagging, asynchrony of chromosome disjunction, and tri-fission were found during the various developmental stages of PMC meiosis. All these abnormalities were significantly higher in sterile hybrids than in fertile hybrids, suggesting that pollen sterility gene interactions tend to increase the chromosomal abnormalities which cause the partial abortion of male gametes and leads to the decline in the seed set of the autotetraploid rice hybrids. © 2011 The Author(s).

Male sterility in plants. Induction, isolation and utilization

International Nuclear Information System (INIS)

Driscoll, C.J.; Barlow, K.K.

1976-01-01

Both induced and spontaneously arising male sterility mutants exist in a number of important plant species. These mutants are somewhat unique in that they effect procedures for breeding improved varieties. They allow for the possibility of easily obtaining large numbers of hybrids, population breeding systems and the production of hybrid varieties. These mutants are normally classified as cytoplasmic mutants or chromosomal mutants, the latter also being referred to as nuclear or genic mutants. Specific examples of these types of sterility are examined in relation to the breeding system of the species and their potential use for varietal development. Male sterility in diploid and polyploid species is compared, with reference to gene duplication in polyploids. The mechanism of male sterility is examined in the various species at the anatomical and biochemical levels. Methods of isolating male sterility mutants are compared and a specific example is outlined for hexaploid wheat. Future use of male sterility mutants for improving varieties of various crops is examined. (author)

High Consumption of Iron Exacerbates Hyperlipidemia, Atherosclerosis, and Female Sterility in Zebrafish via Acceleration of Glycation and Degradation of Serum Lipoproteins

Directory of Open Access Journals (Sweden)

So-Hee Kim

2017-07-01

Full Text Available Elevated serum iron level is linked with an increased risk of diabetes and atherosclerosis. However, the pathological mechanism by which iron affects serum lipoprotein levels is unknown. To elucidate the mechanism, a high dose of ferrous ion was applied (final 60 µM, 120 µM to human serum lipoproteins, macrophages, and human dermal fibroblast (HDF cells. Iron-treated lipoproteins showed loss of antioxidant ability along with protein degradation and multimerization, especially co-treatment with fructose (final 10 mM. In the presence of fructose, HDF cells showed 3.5-fold more severe cellular senescence, as compared to the control, dependent on the dosage of fructose. In macrophages, phagocytosis of acetylated low-density lipoprotein (acLDL was more accelerated by ferrous ion, occurring at a rate that was up to 1.8-fold higher, than acLDL alone. After 24 weeks supplementation with 0.05% and 0.1% ferrous ion in the diet (wt/wt, serum total cholesterol (TC level was elevated 3.7- and 2.1-fold, respectively, under normal diet (ND. Serum triglyceride (TG was elevated 1.4- and 1.7-fold, respectively, under ND upon 0.05% and 0.1% ferrous ion supplementation. Serum glucose level was elevated 2.4- and 1.2-fold under ND and high cholesterol diet (HCD, respectively. However, body weight was decreased by the Fe2+ consumption. Iron consumption caused severe reduction of embryo laying and reproduction ability, especially in female zebrafish via impairment of follicular development. In conclusion, ferrous ion treatment caused more pro-atherogenic, and pro-senescence processes in human macrophages and dermal cells. High consumption of iron exacerbated hyperlipidemia and hyperglycemia as well as induced fatty liver changes and sterility along with reduction of female fertility.

High Consumption of Iron Exacerbates Hyperlipidemia, Atherosclerosis, and Female Sterility in Zebrafish via Acceleration of Glycation and Degradation of Serum Lipoproteins.

Science.gov (United States)

Kim, So-Hee; Yadav, Dhananjay; Kim, Suk-Jeong; Kim, Jae-Ryong; Cho, Kyung-Hyun

2017-07-02

Elevated serum iron level is linked with an increased risk of diabetes and atherosclerosis. However, the pathological mechanism by which iron affects serum lipoprotein levels is unknown. To elucidate the mechanism, a high dose of ferrous ion was applied (final 60 µM, 120 µM) to human serum lipoproteins, macrophages, and human dermal fibroblast (HDF) cells. Iron-treated lipoproteins showed loss of antioxidant ability along with protein degradation and multimerization, especially co-treatment with fructose (final 10 mM). In the presence of fructose, HDF cells showed 3.5-fold more severe cellular senescence, as compared to the control, dependent on the dosage of fructose. In macrophages, phagocytosis of acetylated low-density lipoprotein (acLDL) was more accelerated by ferrous ion, occurring at a rate that was up to 1.8-fold higher, than acLDL alone. After 24 weeks supplementation with 0.05% and 0.1% ferrous ion in the diet (wt/wt), serum total cholesterol (TC) level was elevated 3.7- and 2.1-fold, respectively, under normal diet (ND). Serum triglyceride (TG) was elevated 1.4- and 1.7-fold, respectively, under ND upon 0.05% and 0.1% ferrous ion supplementation. Serum glucose level was elevated 2.4- and 1.2-fold under ND and high cholesterol diet (HCD), respectively. However, body weight was decreased by the Fe 2+ consumption. Iron consumption caused severe reduction of embryo laying and reproduction ability, especially in female zebrafish via impairment of follicular development. In conclusion, ferrous ion treatment caused more pro-atherogenic, and pro-senescence processes in human macrophages and dermal cells. High consumption of iron exacerbated hyperlipidemia and hyperglycemia as well as induced fatty liver changes and sterility along with reduction of female fertility.

Targeted Sequence Capture Provides Insight into Genome Structure and Genetics of Male Sterility in a Gynodioecious Diploid Strawberry, Fragaria vesca ssp. bracteata (Rosaceae)

Science.gov (United States)

Tennessen, Jacob A.; Govindarajulu, Rajanikanth; Liston, Aaron; Ashman, Tia-Lynn

2013-01-01

Gynodioecy is a sexual system wherein females coexist with hermaphrodites. It is of interest not only because male-sterile plants are advantageous in plant breeding but also because it can be a crucial step in the evolutionary transition to entirely separate sexes (dioecy) from a hermaphroditic ancestor. The gynodioecious diploid wild strawberry, Fragaria vesca ssp. bracteata (Rosaceae), is a member of a clade with both dioecious and cultivated species, making it an ideal model in which to study the genetics of male sterility. To create a genetic map of F. v. ssp. bracteata, we identified informative polymorphisms from genomic sequencing (3−5x coverage) of two outbred plants from the same population. Using targeted enrichment, we sequenced 200 bp surrounding each of 6575 polymorphisms in 48 F1 offspring, yielding genotypes at 98% of targeted sites with mean coverage >100x, plus more than 600-kb high-coverage nontargeted sequence. With the resulting linkage map of 7802 stringently filtered markers (5417 targeted), we assessed recombination rates and genomic incongruities. Consistent with past work in strawberries, male sterility is dominant, segregates 1:1, and maps to a single location in the female. Further mapping an additional 55 offspring places male sterility in a gene-dense, 338-kb region of chromosome 4. The region is not syntenic with the sex-determining regions in the closely related octoploids, F. chiloensis and F. virginiana, suggesting either independent origins or translocation. The 57 genes in this region do not include protein families known to control male sterility and thus suggest alternate mechanisms for the suppression of male function. PMID:23749450

Evaluation of steam sterilization conditions for [18F]fludeoxyglucose

International Nuclear Information System (INIS)

Santos, Priscilla F.; Nascimento, Leonardo T.; Valente, Eduardo S.; Silva, Juliana B.; Silveira, Marina B.; Ferreira, Soraya Z.

2011-01-01

[ 18 F]Flu deoxyglucose ( 18 FDG) is the most commonly used radiopharmaceutical for positron emission tomography. Sterile filtration of the final product into sterile vials using 0.22 μm filter membrane is usually adopted for 18 FDG. However, Good Manufacturing Practice (GMP) guidelines recommend heat sterilization as the method of choice to ensure sterility of pharmaceutical preparations. The aim of this study was to essay different steam sterilization conditions in order to choose the best one for 18 FDG. Three different sterilization conditions were essayed. The first one at 121 deg C for 15 minutes, the second one at 135 deg C for 3.5 minutes and the third one at 133 deg C for 2 minutes. 18 FDG pH-formulation was kept around 6.0. At the end of autoclave cycles, 18 FDG sterility was evaluated by direct inoculation of 18 FDG in culture media and radiochemical purity was determined by TLC and HPLC. Results demonstrated that all essayed conditions were able to ensure 18 FDG sterility, but caused a decrease in radiochemical purity of 18 FDG. Autoclave cycle at 133 deg C for 2 minutes was the best essayed condition for 18 FDG terminal sterilization, once it provided the greater radiochemical purity value and took less time. 18 FDG was able to meet specifications after autoclave cycles, what supports the application of steam sterilization in routine 18 FDG production, in compliance with GMP. (author)

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.

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)

Determination of zinc concentration in female reproductive system by instrumental neutron activation

International Nuclear Information System (INIS)

Carvalho, Fernando Ramos de

2009-01-01

Non-surgical female sterilization through the transcervical insertion of quinacrine pellets was considered a definitive, low-cost, safe and effective contraceptive method. The zinc, present in both uterus and Fallopian tubes, inhibit the quinacrine efficiency. The addition of copper increases the efficacy of quinacrine, reducing the risk of pregnancy due to the failure to obstruct the Fallopian tubes. The copper neutralized the deleterious effect of the zinc and so the treatment efficacy is increased. In order to obtain a mapping to study the zinc content in the female reproductive system, samples of both uterus and Fallopian tubes were analyzed by instrumental neutron activation. The results show that, on average, the obtained zinc concentrations in tubes (89 μg-g -1 ) is lower than in the uterus (118 μg-g -1 ), confirming results obtained by other authors. These results will support a research project about non-surgical female sterilization of the 'Faculdade de Medicina da Universidade Federal de Minas Gerais' (Medical School of Federal University of Minas Gerais). The used methodology and obtained results are here reported. (author)

Determination of zinc concentration in female reproductive system by instrumental neutron activation

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Fernando Ramos de, E-mail: framosc@oi.com.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear; Oliveira, Arno Heeren de, E-mail: heeren@nuclear.ufmg.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Medicina. Dept. de Ginecologia e Obstetricia; Ferreira, Claudia R.C.; Ferreira, Ricardo Alberto Neto; Menezes, Maria Angela de B.C., E-mail: claudia@medicina.ufmg.b, E-mail: ranf@cdtn.b, E-mail: menezes@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2009-07-01

Non-surgical female sterilization through the transcervical insertion of quinacrine pellets was considered a definitive, low-cost, safe and effective contraceptive method. The zinc, present in both uterus and Fallopian tubes, inhibit the quinacrine efficiency. The addition of copper increases the efficacy of quinacrine, reducing the risk of pregnancy due to the failure to obstruct the Fallopian tubes. The copper neutralized the deleterious effect of the zinc and so the treatment efficacy is increased. In order to obtain a mapping to study the zinc content in the female reproductive system, samples of both uterus and Fallopian tubes were analyzed by instrumental neutron activation. The results show that, on average, the obtained zinc concentrations in tubes (89 mug-g{sup -1}) is lower than in the uterus (118 mug-g{sup -1}), confirming results obtained by other authors. These results will support a research project about non-surgical female sterilization of the 'Faculdade de Medicina da Universidade Federal de Minas Gerais' (Medical School of Federal University of Minas Gerais). The used methodology and obtained results are here reported. (author)

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.

7 CFR 305.23 - Steam sterilization treatment schedules.

Science.gov (United States)

2010-01-01

... 7 Agriculture 5 2010-01-01 2010-01-01 false Steam sterilization treatment schedules. 305.23... Steam sterilization treatment schedules. Treatment schedule Temperature( °F) Pressure Exposure period (minutes) Directions T303-b-1 10 lbs 20 Use 28″ vacuum. Steam sterilization is not practical for treatment...

Assessing hybrid sterility in Oryza glaberrima x O. sativa hybrid progenies by PCR marker analysis and crossing with wide compatibility varieties.

Science.gov (United States)

Heuer, Sigrid; Miézan, Kouamé M

2003-09-01

Interspecific crossing of the African indigenous rice Oryza glaberrima with Oryza sativa cultivars is hindered by crossing barriers causing 100% spikelet sterility in F(1) hybrids. Since hybrids are partially female fertile, fertility can be restored by back crossing (BC) to a recurrent male parent. Distinct genetic models on spikelet sterility have been developed predicting, e.g., the existence of a gamete eliminator and/or a pollen killer. Linkage of sterility to the waxy starch synthase gene and the chromogen gene C, both located on chromosome 6, have been demonstrated. We selected a segregating BC(2)F(3) population of semi-sterile O. glaberrima x O. sativa indica hybrid progenies for analyses with PCR markers located at the respective chromosome-6 region. These analyses revealed that semi-sterile plants were heterozygous for a marker (OSR25) located in the waxy promoter, whereas fertile progenies were homozygous for the O. glaberrima allele. Adjacent markers showed no linkage to spikelet sterility. Semi-sterility of hybrid progenies was maintained at least until the F(4) progeny generation, suggesting the existence of a pollen killer in this plant material. Monitoring of reproductive plant development showed that spikelet sterility was at least partially due to an arrest of pollen development at the microspore stage. In order to address the question whether genes responsible for F(1) sterility in intraspecific hybrids ( O. sativa indica x japonica) also cause spikelet sterility in interspecific hybrids, crossings with wide compatibility varieties (WCV) were performed. WCV accessions possess "neutral" S-loci ( S(n)) improving fertility in intraspecific hybrids. This experiment showed that the tested S(n)-loci had no fertility restoring effect in F(1) interspecific hybrids. Pollen development was completely arrested at the microspore stage and grains were never obtained after selfing. This suggests that distinct or additional S-loci are responsible for sterility

Color stability of shade guides after autoclave sterilization.

Science.gov (United States)

Schmeling, Max; Sartori, Neimar; Monteiro, Sylvio; Baratieri, Luiz

2014-01-01

This study evaluated the influence of 120 autoclave sterilization cycles on the color stability of two commercial shade guides (Vita Classical and Vita System 3D-Master). The specimens were evaluated by spectrophotometer before and after the sterilization cycles. The color was described using the three-dimensional CIELab system. The statistical analysis was performed in three chromaticity coordinates, before and after sterilization cycles, using the paired samples t test. All specimens became darker after autoclave sterilization cycles. However, specimens of Vita Classical became redder, while those of the Vita System 3D-Master became more yellow. Repeated cycles of autoclave sterilization caused statistically significant changes in the color coordinates of the two shade guides. However, these differences are considered clinically acceptable.

Radio-sterilization and processing of frozen human skin

International Nuclear Information System (INIS)

Zarate S, Herman; Aguirre H, Paulina; Silva R, Samy; Hitschfeld G, Mario

2006-01-01

The Laboratory of Radio-sterilized Biological Tissues Processing (LPTR) belonging to the Chilean Commission of Nuclear Energy and the International Atomic Energy Agency have played a paramount role in our country, concerning the biological tissue processing, which can be radio-sterilized as human skin, pig skin, amniotic membrane, human bone and bovine bone. The frozen radio.-sterilized human skin processing began in 2001, by means of putting into practice the knowledge acquired in training courses through the IAEA and the experience transferred by experts who visited our laboratory. The human skin processing of dead donor can be divided into 6 stages: a) Profuse washing with physiological sterilized serum in to remove the microorganisms, chemical and pharmacological compounds; b) immersion in glycerol solution at 10% to better keep the stored tissues; c) packing, to avoid post manipulation of the sterilized tissue; d) microbiological controls which allow and guarantee a sterility assurance level of 10 6 ; e) radio-sterilization, technique that consists of exposing the grafts to electromagnetic gamma waves which eliminate the microorganisms of the tissue, f) and finally, dispatching and liberation of the frozen sterilized human skin for its clinical use in different centers that take care of burned people. The LPTR receives feedback from surgeons who have used these tissues in order to improve the processing stages based in an integral quality system ISO 9001.2000. The State Health System in our country counts on limited and scarce resources to implement synthetic substitutes that is why It is considered necessary to spread the use of these noble tissues which have sterility assurance and they are processed at low price

Gamma radiation effects on the structure of the sex pheromone producing gland in the female Trogoderma Granarium Everts

International Nuclear Information System (INIS)

Gharib, O.H.; Elnaggar, S.E.M.; Abdelkawy, F.K.

1993-01-01

Effect of gamma irradiation on the structure of the sex pheromone producing gland in 2-day-old females, Trogoderma Granarium Everts was investigated. With the sub sterilizing doses 20 and 40 Gray, the structure started to be destroyed and became undistinguished as well as the sterilizing dose 60 Gray caused complete damage and the glandular tissue appeared as a narrow ribbon. 4 fig

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 ...

Male sterile mutant in Vigna radiata

International Nuclear Information System (INIS)

Pande, Kalpana; Raghuvanshi, S.S.

1987-01-01

Single and combined treatment of γ-rays and 0.25 per cent EMS were tried on Vigna radiata variety K851. A male sterile mutant was isolated in M 2 generation. Experiments indicated male sterility to be recessive and monogenic in nature. 6 figures. (author)

Radiation: A means of sterilization

Energy Technology Data Exchange (ETDEWEB)

Mukherjee, R N [International Atomic Energy Agency, Division of Life Sciences, Radiation Biology Section, Vienna (Austria)

1975-12-15

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.

Reionization in sterile neutrino cosmologies

Science.gov (United States)

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

2016-12-01

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

Revisiting cosmological bounds on sterile neutrinos

Energy Technology Data Exchange (ETDEWEB)

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

2015-04-01

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

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....

21 CFR 880.6860 - Ethylene oxide gas sterilizer.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ethylene oxide gas sterilizer. 880.6860 Section... Miscellaneous Devices § 880.6860 Ethylene oxide gas sterilizer. (a) Identification. An ethylene gas sterilizer is a nonportable device intended for use by a health care provider that uses ethylene oxide (ETO) to...

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

Sterilization of health care products - Ethylene oxide - Part 1: Requirements for development, validation and routine control of a sterilization process for medical devices

International Nuclear Information System (INIS)

2007-01-01

This part of ISO 11135 describes requirements that, if met, will provide an ethylene oxide sterilization process intended to sterilize medical devices, which has appropriate microbicidal activity. Furthermore, compliance with the requirements ensures that this activity is both reliable and reproducible so that it can be predicted, with reasonable confidence, that there is a low level of probability of there being a viable microorganism present on product after sterilization. Specification of this probability is a matter for regulatory authorities and may vary from country to country. The paper provides information on scope, normative references, terms and definitions, quality management systems, sterilizing agent characterization, process and equipment characterization, product definition, process definition, validation, routine monitoring and control, product release from sterilization and maintaining process effectiveness followed by Annex A (Determination of lethal rate of the sterilization process - Biological indicator/bioburden approach), Annex B (Conservative determination of lethal rate of the sterilization process - Overkill approach, annex C (General guidance) and a bibliography.

Intersectional Discrimination of Romani Women Forcibly Sterilized in the Former Czechoslovakia and Czech Republic.

Science.gov (United States)

Albert, Gwendolyn; Szilvasi, Marek

2017-12-01

This paper reviews domestic and international activism seeking justice for Romani and other women harmed by coercive, forced, and involuntary sterilization in the former Czechoslovakia and Czech Republic. Framed by Michel Foucault's theory of biopower, it summarizes the history of these abuses and describes human rights campaigns involving domestic and international litigation, advocacy, and grassroots activism, as well as the responses of the Czech governments. The paper describes how legal and policy work during the past decade has led to recognition of coercive, forced, and involuntary sterilization as a present-day human rights issue worldwide, to the adoption of new guidelines on female sterilization, and to a joint statement on the issue by seven UN agencies. Relying on academic literature, reports by domestic and international human rights groups, state investigations, judgments from Czech courts and the European Court of Human Rights (ECHR), media reports, and the experience of the authors, who have been allies of the Romani women harmed in the Czech Republic since 2005 and 2012, respectively, the paper describes the current state of play with respect to achieving redress for them, including current conceptual, legal, political, and social obstacles and their antecedents in 20th century notions of population control.

Effective sampling range of food-based attractants for female Anastrepha suspensa (Diptera: Tephritidae).

Science.gov (United States)

Kendra, Paul E; Epsky, Nancy D; Heath, Robert R

2010-04-01

Release-recapture studies were conducted with both feral and sterile females of the Caribbean fruit fly, Anastrepha suspensa (Loew) (Diptera: Tephritidae), to determine sampling range for a liquid protein bait (torula yeast/borax) and for a two-component synthetic lure (ammonium acetate and putrescine). Tests were done in a guava, Psidium guajava L., grove and involved releasing flies at a central point and recording the numbers captured after 7 h and 1, 2, 3, and 6 d in an array of 25 Multilure traps located 9-46 m from the release point. In all tests, highest rate of recapture occurred within the first day of release, so estimations of sampling range were based on a 24-h period. Trap distances were grouped into four categories (30 m from release point) and relative trapping efficiency (percentage of capture) was determined for each distance group. Effective sampling range was defined as the maximum distance at which relative trapping efficiency was > or = 25%. This corresponded to the area in which 90% of the recaptures occured. Contour analysis was also performed to document spatial distribution of fly dispersal. In tests with sterile flies, immature females dispersed farther and were recovered in higher numbers than mature females, regardless of attractant, and recapture of both cohorts was higher with torula yeast. For mature feral flies, range of the synthetic lure was determined to be 30 m. With sterile females, effective range of both attractants was 20 m. Contour maps indicated that wind direction had a strong influence on the active space of attractants, as reflected by distribution of captured flies.

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.

Cleaning, disinfection and sterilization of surface prion contamination.

Science.gov (United States)

McDonnell, G; Dehen, C; Perrin, A; Thomas, V; Igel-Egalon, A; Burke, P A; Deslys, J P; Comoy, E

2013-12-01

Prion contamination is a risk during device reprocessing, being difficult to remove and inactivate. Little is known of the combined effects of cleaning, disinfection and sterilization during a typical reprocessing cycle in clinical practice. To investigate the combination of cleaning, disinfection and/or sterilization on reducing the risk of surface prion contamination. In vivo test methods were used to study the impact of cleaning alone and cleaning combined with thermal disinfection and high- or low-temperature sterilization processes. A standardized test method, based on contamination of stainless steel wires with high titres of scrapie-infected brain homogenates, was used to determine infectivity reduction. Traditional chemical methods of surface decontamination against prions were confirmed to be effective, but extended steam sterilization was more variable. Steam sterilization alone reduced the risk of prion contamination under normal or extended exposure conditions, but did show significant variation. Thermal disinfection had no impact in these studies. Cleaning with certain defined formulations in combination with steam sterilization can be an effective prion decontamination process, in particular with alkaline formulations. Low-temperature, gaseous hydrogen peroxide sterilization was also confirmed to reduce infectivity in the presence and absence of cleaning. Prion decontamination is affected by the full reprocessing cycle used on contaminated surfaces. The correct use of defined cleaning, disinfection and sterilization methods as tested in this report in the scrapie infectivity assay can provide a standard precaution against prion contamination. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

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

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.

Production of a sterile species: Quantum kinetics

Science.gov (United States)

Boyanovsky, D.; Ho, C. M.

2007-10-01

Production of a sterile species is studied within an effective model of active-sterile neutrino mixing in a medium in thermal equilibrium. The quantum kinetic equations for the distribution functions and coherences are obtained from two independent methods: the effective action and the quantum master equation. The decoherence time scale for active-sterile oscillations is τdec=2/Γaa, but the evolution of the distribution functions is determined by the two different time scales associated with the damping rates of the quasiparticle modes in the medium: Γ1=Γaacos⁡2θm; Γ2=Γaasin⁡2θm where Γaa is the interaction rate of the active species in the absence of mixing and θm the mixing angle in the medium. These two time scales are widely different away from Mikheyev-Smirnov-Wolfenstein resonances and preclude the kinetic description of active-sterile production in terms of a simple rate equation. We give the complete set of quantum kinetic equations for the active and sterile populations and coherences and discuss in detail the various approximations. A generalization of the active-sterile transition probability in a medium is provided via the quantum master equation. We derive explicitly the usual quantum kinetic equations in terms of the “polarization vector” and show their equivalence to those obtained from the quantum master equation and effective action.

Effect of sub-sterilizing doses of gamma radiation on Spodoptera frugiperda (Smith) pupae

International Nuclear Information System (INIS)

Duarte Aguilar, J.A.; Arthur, Valter

1998-01-01

Studies were undertaken to verify the effects of sub-sterilizing doses of gamma radiations on pupae of Spodoptera frugiperda (Smith) and transfer of genetic heredity on the first and second generations. Statistical analysis showed difference in the ageing effect of gamma radiations on the larval phase and larval viability ranged between 72 and 94 percent, when irradiated (50 Gy) males or females were crossed with non-irradiated adults. With doses of 100, 125, 150 and 175 Gy the crossing of irradiated males x non irradiated females the larval viability was between 64 and 94 per cent in F-1 and F-2 generations. The duration and other life parameters of the pupae and adults did not differ from the controls. The egg laying ability was not affected by doses up to 150 Gy on both the sexes. If irradiated females with doses of 175 and 200 Gy were crossed with non-irradiated males, the egg laying was inhibited when males were irradiated with one of these doses, the offspring females did not lay eggs or laid non-fertile eggs. (author)

Induction of male sterility in rice using chemical mutagens

Energy Technology Data Exchange (ETDEWEB)

Minocha, J L; Gupta, R K [Department of Genetics, Punjab Agricultural University, Ludhiana (India)

1988-07-01

Full text: To diversify the sources of cytoplasmic male sterility for hybrid seed production in rice (Oryza sativa L.) attempts were made to induce this character in a popular indica cultivar PR 106 through chemical mutagens. Seeds were treated with 0.4% ethidium bromide (EB) for 24 or 48h at 10 deg. C, with 0.4% ethyl methanesulphonate (EMS) for 24 or 48h at 10 deg. C for 16 hr at 20 deg. C or with 0.2% streptomycin sulphate (SM) for 24 or 48 hr at 10 deg. C. In M{sub 2} male sterile plants were detected in eleven different progenies, one from SM treatment and the remaining from EMS treatments. All the sterile plants had 100% non-stainable aborted pollen. Seed set upon open-pollination of the male sterile plants with the variety PR 106 ranged from 0.03 to 4.93 per cent whereas no seed formed in bagged panicles. In M{sub 3}, open-pollinated progenies of the male sterile plants and their fertile sibs were further studied. Two progenies segregated for male sterility, all others had only fertile plants. In one of the segregating progenies, five out of six and in the other nine out of fourteen plants were male sterile. The progenies of fertile sibs did not have any male sterile plant. The results indicate that sterility of cytoplasmic type has been induced by EMS. The parental variety PR 106 acts as the maintainer. (author)

Induction of male sterility in rice using chemical mutagens

International Nuclear Information System (INIS)

Minocha, J.L.; Gupta, R.K.

1988-01-01

Full text: To diversify the sources of cytoplasmic male sterility for hybrid seed production in rice (Oryza sativa L.) attempts were made to induce this character in a popular indica cultivar PR 106 through chemical mutagens. Seeds were treated with 0.4% ethidium bromide (EB) for 24 or 48h at 10 deg. C, with 0.4% ethyl methanesulphonate (EMS) for 24 or 48h at 10 deg. C for 16 hr at 20 deg. C or with 0.2% streptomycin sulphate (SM) for 24 or 48 hr at 10 deg. C. In M 2 male sterile plants were detected in eleven different progenies, one from SM treatment and the remaining from EMS treatments. All the sterile plants had 100% non-stainable aborted pollen. Seed set upon open-pollination of the male sterile plants with the variety PR 106 ranged from 0.03 to 4.93 per cent whereas no seed formed in bagged panicles. In M 3 , open-pollinated progenies of the male sterile plants and their fertile sibs were further studied. Two progenies segregated for male sterility, all others had only fertile plants. In one of the segregating progenies, five out of six and in the other nine out of fourteen plants were male sterile. The progenies of fertile sibs did not have any male sterile plant. The results indicate that sterility of cytoplasmic type has been induced by EMS. The parental variety PR 106 acts as the maintainer. (author)

Sterile insect supply, emergence, and release

International Nuclear Information System (INIS)

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

2005-01-01

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

Sterilization and disinfection: the prevailing indifference

International Nuclear Information System (INIS)

Mirza, I.

2007-01-01

To evaluate the knowledge and attitude of health care professionals towards the process of sterilization and disinfection, and to check the adequacy of the reading material accessible to them. The study comprised of three components. In the first part, sections devoted to this subject in the popular books read by the students of operation theatre assistant course and students of diploma in general nursing were examined for adequacy and authenticity of information. In the second part, standard operating procedures were examined regarding sterilization of textile, rubber tubes of suction units and diathermy hand pieces of 20 operation theatres of three teaching hospital attached to undergraduate medical college of Punjab. In the third part of the study, working knowledge of 64 practicing operation theatre assistants and 57 practicing nurses was assessed through a questionnaire. It was found that popular books either did not contain the required information or the information provided was misleading or incorrect. Standard operating procedures for sterilization of selected items of all the operation theatres studied fell much below the standard of practice desired in the light of current knowledge and contemporary practices. Finally the working knowledge of the professionals studied was much below the bare minimum expected by the profession. There is a dire need for upgrading the knowledge and attitude of health care professionals regarding sterilization, besides improving the operation theatres sterilization procedures. (author)

Long-term effects of prenatal x-ray of human females: reproductive experience

International Nuclear Information System (INIS)

Meyer, M.B.; Tonascia, J.

1981-01-01

A cohort of singleton black human females exposed to diagnostic x-ray in utero and controls matched by parity, hospital of birth and birthdate have been followed to ages 25 to 30 years in Baltimore, Maryland. The search for possible effects of prenatal irradiation has focused on health, growth, development, and reproductive experience of exposed and control women. This paper reports findings related to reproductive experience. From an original data set of 1458 matched exposed-control pairs of women, questionnaire responses were received from 1109 exposed and 1124 control women including 852 each from pairs in which both the exposed and control woman responded. After careful search for alternative explanations of the findings, the authors concluded that females exposed in utero to low doses of x-ray (probably 1 to 5 rads) had significant increases in their rates of early onset of menses, births at age 15 years or less, numbers of living children, stillbirths, and sterilizing operations by their mid-twenties. These findings are compatible with animal studies in which prenatal irradiation kills many oocytes, but accelerates the development of remaining cells to stages more closely correlated with fertility. Although these animals subsequently became sterile, this cannot be tested in the current study because significantly more of the irradiated women have had surgical sterilizations

Status of radiation sterilization of healthcare products in China

International Nuclear Information System (INIS)

Zhu Nankang; Wang Chunlei; Teng Weifang

2004-01-01

This paper describes the status of 60 Co radiation facilities both in service and under construction in China and examines the future market for radiation sterilization of healthcare products. Policies for developing the industry of radiation sterilization are also put forward; these include implementation of appropriate quality systems, scale-up and merging of existing radiation facilities, development of electron beam radiation for sterilization purposes and increasing awareness of the technology of radiation sterilization

Sterilization processes. Meeting the demands of today's health care technology.

Science.gov (United States)

Crow, S

1993-09-01

Universal Precautions dictate sterilization for all invasive equipment that break the blood barrier; however, current methods of sterilization, such as steam and ethylene oxide gas (ETO), are not compatible with many of the delicate, heat-sensitive surgical instruments used in modern health care. In addition, traditional sterilization methods are often too time consuming for practical use in the operating room. Clearly, new sterilization processes need to be developed. In this article, the criteria modern sterilization processes must meet and how some manufacturers plan to meet this challenge are discussed. In addition, the pros and cons of using peracetic acid (the newest sterilization process currently available) are examined.

Sterilization of health care products - Radiation. Part 1: Requirements for development, validation and routine control of a sterilization process for medical devices

International Nuclear Information System (INIS)

2006-01-01

A sterile medical device is one that is free of viable microorganisms. International Standards, which specify requirements for validation and routine control of sterilization processes, require, when it is necessary to supply a sterile medical device, that adventitious microbiological contamination of a medical device prior to sterilization be minimized. Even so, medical devices produced under standard manufacturing conditions in accordance with the requirements for quality management systems (see, for example, ISO 13485) may, prior to sterilization, have microorganisms on them, albeit in low numbers. Such medical devices are non-sterile. The purpose of sterilization is to inactivate the microbiological contaminants and thereby transform the nonsterile medical devices into sterile ones. The kinetics of inactivation of a pure culture of microorganisms by physical and/or chemical agents used to sterilize medical devices can generally best be described by an exponential relationship between the numbers of microorganisms surviving and the extent of treatment with the sterilizing agent; inevitably this means that there is always a finite probability that a microorganism may survive regardless of the extent of treatment applied. For a given treatment, the probability of survival is determined by the number and resistance of microorganisms and by the environment in which the organisms exist during treatment. It follows that the sterility of any one medical device in a population subjected to sterilization processing cannot be guaranteed and the sterility of a processed population is defined in terms of the probability of there being a viable microorganism present on a medical device. This part of ISO 11137 describes requirements that, if met, will provide a radiation sterilization process intended to sterilize medical devices, that has appropriate microbicidal activity. Furthermore, compliance with the requirements ensures that this activity is both reliable and

Global dynamics of a PDE model for aedes aegypti mosquitoe incorporating female sexual preference

KAUST Repository

Parshad, Rana

2011-01-01

In this paper we study the long time dynamics of a reaction diffusion system, describing the spread of Aedes aegypti mosquitoes, which are the primary cause of dengue infection. The system incorporates a control attempt via the sterile insect technique. The model incorporates female mosquitoes sexual preference for wild males over sterile males. We show global existence of strong solution for the system. We then derive uniform estimates to prove the existence of a global attractor in L-2(Omega), for the system. The attractor is shown to be L-infinity(Omega) regular and posess state of extinction, if the injection of sterile males is large enough. We also provide upper bounds on the Hausdorff and fractal dimensions of the attractor.

Current Sterilization Protocols-An Orthodontic Perspective

Directory of Open Access Journals (Sweden)

Abraham Vinod Korath

2010-01-01

Part I of this article focuses on the working principles of various methods of sterilization with an appraisalof their effects on orthodontic instruments. Additionally,contributory factors of instrument damage is enumerated to emphasis the importance of adhering to precise protocols and manufacturer recommendations as well as in alleviating some misconceptions about sterilization induced instrument damage.

Present studies on the radio-sterilized drugs

International Nuclear Information System (INIS)

Marciniec, B.; Dettlaff, K.

2007-01-01

Lecture presents present status of radiosterilization of drugs and medical materials as compared to other sterilization methods. Literature review is shown on degradation of different kinds of drugs sterilized upon action of the sterilising doses of radiation

Dark matter relic abundance and light sterile neutrinos

Energy Technology Data Exchange (ETDEWEB)

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

2017-01-09

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

submitter Prospects of Sterile Neutrino Search with the FCC-ee

CERN Document Server

Bay Nielsen, Sissel

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

Dark radiation sterile neutrino candidates after Planck data

Energy Technology Data Exchange (ETDEWEB)

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

2013-11-01

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

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

Sterile Neutrinos in Cold Climates

International Nuclear Information System (INIS)

Jones, Benjamin J.P.

2015-01-01

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 sin 2 2θ 24 ≤ 0.02 at m 2 ~ 0.3 eV 2 , and the LSND and MiniBooNE allowed regions are excluded at

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

Science.gov (United States)

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

2018-04-01

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

Comparative transcript profiling of fertile and sterile flower buds from multiple-allele-inherited male sterility in Chinese cabbage (Brassica campestris L. ssp. pekinensis).

Science.gov (United States)

Zhou, Xue; Liu, Zhiyong; Ji, Ruiqin; Feng, Hui

2017-10-01

We studied the underlying causes of multiple-allele-inherited male sterility in Chinese cabbage (Brassica campestris L. ssp. pekinensis) by identifying differentially expressed genes (DEGs) related to pollen sterility between fertile and sterile flower buds. In this work, we verified the stages of sterility microscopically and then performed transcriptome analysis of mRNA isolated from fertile and sterile buds using Illumina HiSeq 2000 platform sequencing. Approximately 80% of ~229 million high-quality paired-end reads were uniquely mapped to the reference genome. In sterile buds, 699 genes were significantly up-regulated and 4096 genes were down-regulated. Among the DEGs, 28 pollen cell wall-related genes, 54 transcription factor genes, 45 phytohormone-related genes, 20 anther and pollen-related genes, 212 specifically expressed transcripts, and 417 DEGs located on linkage group A07 were identified. Six transcription factor genes BrAMS, BrMS1, BrbHLH089, BrbHLH091, BrAtMYB103, and BrANAC025 were identified as putative sterility-related genes. The weak auxin signal that is regulated by BrABP1 may be one of the key factors causing pollen sterility observed here. Moreover, several significantly enriched GO terms such as "cell wall organization or biogenesis" (GO:0071554), "intrinsic to membrane" (GO:0031224), "integral to membrane" (GO:0016021), "hydrolase activity, acting on ester bonds" (GO:0016788), and one significantly enriched pathway "starch and sucrose metabolism" (ath00500) were identified in this work. qRT-PCR, PCR, and in situ hybridization experiments validated our RNA-seq transcriptome analysis as accurate and reliable. This study will lay the foundation for elucidating the molecular mechanism(s) that underly sterility and provide valuable information for studying multiple-allele-inherited male sterility in the Chinese cabbage line 'AB01'.

Sterile Neutrino Search with MINOS