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Sample records for bed bug problem

  1. Bed Bugs

    Science.gov (United States)

    Prevent, identify, and treat bed bug infestations using EPA’s step-by-step guides, based on IPM principles. Find pesticides approved for bed bug control, check out the information clearinghouse, and dispel bed bug myths.

  2. Protecting Your Home from Bed Bugs

    Science.gov (United States)

    ... your home: Inspect the luggage rack in your hotel room for bed bugs. Check secondhand furniture, beds, ... with Bed Bug Problems Discover. Accessibility EPA Administrator Budget & Performance Contracting Grants January 19, 2017 Web Snapshot ...

  3. Bed Bug Infestations and Control Practices in China: Implications for Fighting the Global Bed Bug Resurgence

    Directory of Open Access Journals (Sweden)

    Changlu Wang

    2011-04-01

    Full Text Available The bed bug resurgence in North America, Europe, and Australia has elicited interest in investigating the causes of the widespread and increasing infestations and in developing more effective control strategies. In order to extend global perspectives on bed bug management, we reviewed bed bug literature in China by searching five Chinese language electronic databases. We also conducted telephone interviews of 68 pest control firms in two cities during March 2011. In addition, we conducted telephone interviews to 68 pest control companies within two cities in March 2011. Two species of bed bugs (Cimex lectularius L. and Cimex hemipterus (F. are known to occur in China. These were common urban pests before the early1980s. Nationwide “Four-Pest Elimination” campaigns (bed bugs being one of the targeted pests were implemented in China from 1960 to the early 1980s. These campaigns succeeded in the elimination of bed bug infestations in most communities. Commonly used bed bug control methods included applications of hot water, sealing of bed bug harborages, physical removal, and applications of residual insecticides (mainly organophosphate sprays or dusts. Although international and domestic travel has increased rapidly in China over the past decade (2000–2010, there have only been sporadic new infestations reported in recent years. During 1999–2009, all documented bed bug infestations were found in group living facilities (military dormitories, worker dormitories, and prisons, hotels, or trains. One city (Shenzhen city near Hong Kong experienced significantly higher number of bed bug infestations. This city is characterized by a high concentration of migratory factory workers. Current bed bug control practices include educating residents, washing, reducing clutter, putting items under the hot sun in summer, and applying insecticides (pyrethroids or organophosphates. There have not been any studies or reports on bed bug insecticide

  4. Bed Bug Epidemic: A Challenge to Public Health

    Science.gov (United States)

    Ratnapradipa, Dhitinut; Ritzel, Dale O.; Haramis, Linn D.; Bliss, Kadi R.

    2011-01-01

    In recent years, reported cases of bed bug infestations in the U.S. and throughout the world have escalated dramatically, posing a global public health problem. Although bed bugs are not known to transmit disease to humans, they pose both direct and indirect public health challenges in terms of health effects, treatment, cost, and resource…

  5. The odorant receptor co-receptor from the bed bug, Cimex lectularius L.

    Directory of Open Access Journals (Sweden)

    Immo A Hansen

    Full Text Available Recently, the bed bug, Cimex lectularius L. has re-emerged as a serious and growing problem in many parts of the world. Presence of resistant bed bugs and the difficulty to eliminate them has renewed interest in alternative control tactics. Similar to other haematophagous arthropods, bed bugs rely on their olfactory system to detect semiochemicals in the environment. Previous studies have morphologically characterized olfactory organs of bed bugs' antenna and have physiologically evaluated the responses of olfactory receptor neurons (ORNs to host-derived chemicals. To date, odorant binding proteins (OBPs and odorant receptors (ORs associated with these olfaction processes have not been studied in bed bugs. Chemoreception in insects requires formation of heteromeric complexes of ORs and a universal OR coreceptor (Orco. Orco is the constant chain of every odorant receptor in insects and is critical for insect olfaction but does not directly bind to odorants. Orco agonists and antagonists have been suggested as high-value targets for the development of novel insect repellents. In this study, we have performed RNAseq of bed bug sensory organs and identified several odorant receptors as well as Orco. We characterized Orco expression and investigated the effect of chemicals targeting Orco on bed bug behavior and reproduction. We have identified partial cDNAs of six C. lectularius OBPs and 16 ORs. Full length bed bug Orco was cloned and sequenced. Orco is widely expressed in different parts of the bed bug including OR neurons and spermatozoa. Treatment of bed bugs with the agonist VUAA1 changed bed bug pheromone-induced aggregation behavior and inactivated spermatozoa. We have described and characterized for the first time OBPs, ORs and Orco in bed bugs. Given the importance of these molecules in chemoreception of this insect they are interesting targets for the development of novel insect behavior modifiers.

  6. Effectiveness of Bed Bug Pesticides

    Science.gov (United States)

    Before EPA allows a bed bug claim on a label, the product must be supported by data showing it will kill bed bugs when applied according to the label. Also consider factors such as extent of infestation, site preparation, and insect life stages.

  7. Find a Bed Bug Pesticide Product

    Science.gov (United States)

    Introduces the Bed Bug Product Search Tool, to help consumers find EPA-registered pesticides for bed bug infestation control. Inclusion in this database is not an endorsement. Always follow label directions carefully.

  8. Bed Bug Guidance for School Nurses

    Science.gov (United States)

    School nurses are often called upon to provide vital information to students, parents, teachers, and administrators. These tips on identifying, managing and preventing bed bugs will help you to effectively respond if bed bugs appear in your school.

  9. Cases of bed bug (Cimex lectularius infestations in Northwest Italy

    Directory of Open Access Journals (Sweden)

    Federica Giorda

    2013-12-01

    Full Text Available Bed bugs (Cimex lectularius have been a common problem for humans for at least 3,500 years and in Europe their presence was endemic until the end of World War II, when infestations began to decrease. However, since the beginning of the 21st century new cases of infestations have been reported in developed countries. Many theories have been put forward to explain this change of direction, but none has been scientifically proven. The aim of this study is to provide some reports of bed bug infestations in Northern Italy (Liguria, Piedmont and Aosta valley regions and a brief summary about their identification, clinical significance, bioecology and control. From 2008 to date, 17 bed bug infestations were identified in Northwest Italy. Knowledge about the presence and distribution of bed bugs in Italy is scanty, prior to this work only 2 studies reported the comeback of these arthropods in the Italian territory; further investigations would be necessary to better understand the current situation.

  10. Real-Time Measurement of Volatile Chemicals Released by Bed Bugs during Mating Activities

    DEFF Research Database (Denmark)

    Kilpinen, Ole Østerlund; Liu, Dezhao; Adamsen, Anders Peter

    2012-01-01

    In recent years, bed bug (Hemiptera: Cimicidae) problems have increased dramatically in many parts of the world, leading to a renewed interest in their chemical ecology. Most studies of bed bug semiochemicals have been based on the collection of volatiles over a period of time followed by chemical...

  11. Bed Bugs and Schools

    Science.gov (United States)

    Bed bugs have long been a pest – feeding on blood, causing itchy bites and generally irritating their human hosts. They are successful hitchhikers, and can move from an infested site to furniture, bedding, baggage, boxes, and clothing.

  12. Print a Bed Bug Card - (Single Cards)

    Science.gov (United States)

    Two sets of business-card-sized lists of tips for recognizing bed bugs and the signs of an infestation, including a photo of bed bugs to assist identification. One card is for general use around home or office, the other for travelers.

  13. Bed Bugs FAQs

    Science.gov (United States)

    ... Europe. Bed bugs have been found in five-star hotels and resorts and their presence is not ... Health – Division of Parasitic Diseases Email Recommend Tweet YouTube Instagram Listen Watch RSS ABOUT About CDC Jobs ...

  14. Role of vision and mechanoreception in bed bug, Cimex lectularius L. behavior.

    Directory of Open Access Journals (Sweden)

    Narinderpal Singh

    Full Text Available The role of olfactory cues such as carbon dioxide, pheromones, and kairomones in bed bug, Cimex lectularius L. behavior has been demonstrated. However, the role of vision and mechanoreception in bed bug behavior is poorly understood. We investigated bed bug vision by determining their responses to different colors, vertical objects, and their ability to detect colors and vertical objects under low and complete dark conditions. Results show black and red paper harborages are preferred compared to yellow, green, blue, and white harborages. A bed bug trapping device with a black or red exterior surface was significantly more attractive to bed bugs than that with a white exterior surface. Bed bugs exhibited strong orientation behavior toward vertical objects. The height (15 vs. 30 cm tall and color (brown vs. black of the vertical object had no significant effect on orientation behavior of bed bugs. Bed bugs could differentiate color and detect vertical objects at very low background light conditions, but not in complete darkness. Bed bug preference to different substrate textures (mechanoreception was also explored. Bed bugs preferred dyed tape compared to painted tape, textured painted plastic, and felt. These results revealed that substrate color, presence of vertical objects, and substrate texture affect host-seeking and harborage-searching behavior of bed bugs. Bed bugs may use a combination of vision, mechanoreception, and chemoreception to locate hosts and seek harborages.

  15. Getting Rid of Bed Bugs

    Science.gov (United States)

    ... Directory Planning, Budget and Results Jobs and Internships Headquarters Offices Regional Offices Labs and Research Centers Bed ... to be careful in how you select a company. Related Information Collaborative Strategy on Bed Bugs - highlights ...

  16. EPA-Registered Bed Bug Products

    Science.gov (United States)

    ... rest or hide in hampers, bed frames, even furniture); Failing to treat adjacent areas where bed bugs ... to work (some pesticides, such as desiccators or growth regulators, may be very effective but take some ...

  17. Bed Bug Myths

    Science.gov (United States)

    Learn the truth about bed bugs, such as how easy they are to see with the naked eye, their preferred habitat, whether they transmit diseases, their public health effects, and whether pesticides are the best way to deal with an infestation.

  18. Infestation by pyrethroids resistant bed bugs in the suburb of Paris, France

    Directory of Open Access Journals (Sweden)

    Durand R.

    2012-11-01

    Full Text Available Bed bugs are hematophagous insects responsible for a re-emerging and challenging indoor pest in many countries. Bed bugs infestations may have health consequences including nuisance biting, cutaneous and systemic reactions. This resurgence can probably be attributed to factors such as increased international travel and development of resistance against insecticides. Resistance against pyrethroids has been reported several times from the USA and rarely in Europe. In France, very few data on bed bugs are available. The present study aimed to assess the infestation by bed bugs of a complex of two high-rise apartment buildings in the suburb of Paris and to evaluate their susceptibility to pyrethroid insecticides. We inspected for bed bugs 192 out of 198 apartments units (97% and interviewed their residents. 76 (39.6% apartments were infested. Among the 97 residents living in infested apartments, 53 (54.6% reported bed bug bites. A total of 564 bed bugs were collected in the infested units. Bioassays showed that 54 out of 143 bed bugs were resistant to pyrethroids (37.8%; 95% confidence interval: 29.9-45.7%. DNA sequencing showed that all bed bugs tested (n = 124 had homozygous L925I kdr-like gene mutation. The level of pyrethroid resistance found indicates that this phenomenon was already established in the site and prompts the need to reevaluate the wide use of pyrethroids to control bed bugs.

  19. Bed Bug Information Clearinghouse

    Science.gov (United States)

    Its purpose is to help states, communities, and consumers in efforts to prevent and control bed bug infestations. Currently includes only reviewed material from federal/state/local government agencies, extension services, and universities.

  20. Essential oils as fumigants for bed bugs (Hemiptera: Cimicidae)

    Science.gov (United States)

    In Petri dish assays, fumigation of a pyrethroid-susceptible strain of bed bugs Cimex lectularius L. (Hemiptera: Cimicidae) with various essential oils resulted in mortality that approached or equaled 100%, after 5 days. However, when bed bugs were exposed to the same essential oils in sealed, comme...

  1. Comparison of Three Bed Bug Management Strategies in a Low-Income Apartment Building

    Directory of Open Access Journals (Sweden)

    Changlu Wang

    2012-04-01

    Full Text Available Bed bug (Cimex lectularius L. infestations are currently controlled by a variety of non-chemical and chemical methods. There have been few studies on the comparative effectiveness of these control techniques. We evaluated three bed bug management strategies in an apartment building: (1 non-chemical methods only (n = 9; (2 insecticides only (n = 6; and (3 integrated pest management including both non-chemical methods and insecticides (n = 9. The apartments were one-bedroom units occupied by seniors or people with disabilities. Bed bug numbers in each apartment were determined by visual inspection and/or installing intercepting devices under bed and sofa legs. The median (min, max bed bug counts in the non-chemical methods only, insecticides only, and integrated pest management (IPM treatment were: 4 (1, 57, 19 (1, 250, and 14 (1, 219, respectively prior to the treatments. The apartments were retreated if found necessary during biweekly to monthly inspections. After 10 weeks, bed bugs were found to be eliminated from 67, 33, and 44% of the apartments in the three treatment groups, respectively. The final (after 10 weeks median (min, max bed bug counts in the non-chemical methods only, insecticides only, and IPM treatment were: 0 (0, 134, 11.5 (0, 58, and 1 (0, 38, respectively. There were no significant differences in the speed of bed bug count reduction or the final bed bug counts. Lack of resident cooperation partially contributed to the failure in eliminating bed bugs from some of the apartments. Results of this study suggest that non-chemical methods can effectively eliminate bed bugs in lightly infested apartments.

  2. Posttreatment Feeding Affects Mortality of Bed Bugs (Hemiptera: Cimicidae) Exposed to Insecticides.

    Science.gov (United States)

    Singh, Narinderpal; Wang, Changlu; Cooper, Richard

    2016-02-01

    Insecticide sprays and dusts are used for controlling bed bugs, Cimex lectularius L. In natural environments, bed bugs have daily access to hosts after they are exposed to insecticides. The established laboratory insecticide bioassay protocols do not provide feeding after insecticide treatments, which can result in inflated mortality compared with what would be encountered in the field. We evaluated the effect of posttreatment feeding on mortality of bed bugs treated with different insecticides. None of the insecticides tested had a significant effect on the amount of blood consumed and percent feeding. The effect of posttreatment feeding on bed bug mortality varied among different insecticides. Feeding significantly reduced mortality in bed bugs exposed to deltamethrin spray, an essential oil mixture (Bed Bug Fix) spray, and diatomaceous earth dust. Feeding increased the mean survival time for bed bugs treated with chlorfenapyr spray and a spray containing an essential oil mixture (Ecoraider), but did not affect the final mortality. First instars hatched from eggs treated with chlorfenapyr liquid spray had reduced feeding compared with nymphs hatched from nontreated eggs. Those nymphs hatched from eggs treated with chlorfenapyr liquid spray and successfully fed had reduced mortality and a higher mean survival time than those without feeding. We conclude that the availability of a bloodmeal after insecticide exposure has a significant effect on bed bug mortality. Protocols for insecticide efficacy testing should consider offering a bloodmeal to the treated bed bugs within 1 to 3 d after treatment. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Histamine as an emergent indoor contaminant: Accumulation and persistence in bed bug infested homes.

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    Zachary C DeVries

    Full Text Available Histamine is used in bronchial and dermal provocation, but it is rarely considered an environmental risk factor in allergic disease. Because bed bugs defecate large amounts of histamine as a component of their aggregation pheromone, we sought to determine if histamine accumulates in household dust in bed bug infested homes, and the effects of bed bug eradication with spatial heat on histamine levels in dust. We collected dust in homes and analyzed for histamine before, and up to three months after bed bug eradication. Histamine levels in bed bug infested homes were remarkably high (mean = 54.6±18.9 μg/100 mg of sieved household dust and significantly higher than in control homes not infested with bed bugs (mean < 2.5±1.9 μg/100 mg of sieved household dust. Heat treatments that eradicated the bed bug infestations failed to reduce histamine levels, even three months after treatment. We report a clear association between histamine levels in household dust and bed bug infestations. The high concentrations, persistence, and proximity to humans during sleep suggest that bed bug-produced histamine may represent an emergent contaminant and pose a serious health risk in the indoor environment.

  4. Histamine as an emergent indoor contaminant: Accumulation and persistence in bed bug infested homes.

    Science.gov (United States)

    DeVries, Zachary C; Santangelo, Richard G; Barbarin, Alexis M; Schal, Coby

    2018-01-01

    Histamine is used in bronchial and dermal provocation, but it is rarely considered an environmental risk factor in allergic disease. Because bed bugs defecate large amounts of histamine as a component of their aggregation pheromone, we sought to determine if histamine accumulates in household dust in bed bug infested homes, and the effects of bed bug eradication with spatial heat on histamine levels in dust. We collected dust in homes and analyzed for histamine before, and up to three months after bed bug eradication. Histamine levels in bed bug infested homes were remarkably high (mean = 54.6±18.9 μg/100 mg of sieved household dust) and significantly higher than in control homes not infested with bed bugs (mean emergent contaminant and pose a serious health risk in the indoor environment.

  5. How to Find Bed Bugs

    Science.gov (United States)

    Find and correctly identify an infestation early before it becomes widespread. Look for rusty or reddish stains and pinpoint dark spots on bed sheets or mattresses, and search for bugs near the piping, seams and tags of the mattress and box spring.

  6. Prevalence of bed bug (Cimex lectularius in human settlement area of Bahnamir, Iran

    Directory of Open Access Journals (Sweden)

    Seyyed Farzad Motevalli Haghi

    2014-09-01

    Full Text Available Objective: To survey the factors concerning with bed bugs epidemiology among human settlement area of Bahnamir, Iran in 2012-2013. Methods: Bed bugs were collected from 500 households which lived in eight villages in suburban areas. After random cluster classification, we checked their houses to collect information on presence of bed bugs. When bed bugs infestation revealed, they were preserved in properly labeled specimen containing 70% alcohol. Bugs were transferred to the Faculty of Health and identified by stereomicroscopy. A questionnaire was filled by the owners. The recorded data were coded and analyzed statistically using the Chi-square test. Results: In the study area, 14 from 500 families were infested by bed bugs which revealed almost 2.8% of infestation in that area. Five infested villages had shown 62.50% infestation. From the total of 256 caught bugs, 56.45%, 31.25%, 8.59%, and 3.91% was separated from bedroom, setting room, kitchen and other parts of the infested houses, respectively. Regarding to 256 trapped bugs in the bedroom, 33.2% were immature (nymph and 66.8% were mature. Conclusions: The results illustrated the role of education and guidance of the owners towards improving personal hygiene and public health with using insecticides to control by professional persons, not using secondhand instrument in the home and washing sheets and blankets and drying on suitable hot drier in order to reduce the infestation rate of bed bug among human settlement.

  7. Long-Term Efficacy of Various Natural or "Green" Insecticides against Bed Bugs: A Double-Blind Study.

    Science.gov (United States)

    Goddard, Jerome

    2014-11-28

    Bed bugs are resurging throughout the world, and, thus, effective pest control strategies are constantly needed. A few studies have evaluated 25(b) and other natural, or so-called "green" products, as well as over-the-counter insecticides for bed bugs, but additional studies are needed to determine efficacy of bed bug control products. This double-blinded research project was initiated to examine long-term effectiveness of six commercially available natural or "green" insecticides against bed bugs and to compare them with three known traditional residual products. Water was used as a control. Products were evaluated against both susceptible and resistant strains of bed bugs (1200 bugs each), and two different substrates were used. Temprid(®) (Bayer Corporation, Monheim, Germany), Transport(®) (FMC Corp., Philadelphia, PA, USA), Invader(®) (FMC Corporation, Philadelphia, PA USA), Cimexa(®) (Rockwell Laboratories, Kansas City, MO, USA), and BBT-2000(®) (Swepe-Tite LLC, Tupelo, MS, USA) were the only products which showed any substantial (>40%) bed bug control upon exposure to treated substrates after the six-month waiting period, although results with the resistant bed bug strain were much reduced. Alpine dust(®) (BASF Corporation, Florham Park, NJ, USA) killed 27% of bed bugs or less, depending on strain and substrate. EcoRaider(®) (North Bergen, NJ, USA) and Mother Earth D(®) (Whitmire Microgen, Florham Park, NJ, USA) (diatomaceous earth) produced 11% control or less. Cimi-Shield Protect(®) (Pest Barrier, Carson, CA, USA) showed no activity against bed bugs in this study. Analysis using SAS software showed a three-way interaction between treatment, substrate, and bed bug strain (Numerator DF 9; Denominator DF 80; F = 4.90; p < 0.0001).

  8. Do-it-yourself Bed Bug Control

    Science.gov (United States)

    ... Contact Us Share Do-it-yourself Bed Bug Control Información relacionada disponible en español Can you treat ... all of the residents to participate. Achieving complete control can take weeks to months, depending on the ...

  9. Bed Bugs are Public Health Pests

    Science.gov (United States)

    EPA and the Centers for Disease Control and Prevention (CDC) issued a joint statement on the public health impacts of bed bugs, which are blood-sucking ectoparasites (external parasites). EPA also has a pesticide registration notice on this topic.

  10. 76 FR 550 - Second National Bed Bug Summit; Notice of Public Meeting

    Science.gov (United States)

    2011-01-05

    ... identify knowledge gaps and barriers to effective community-wide bed bug control; propose the next steps in addressing knowledge gaps and eliminating barriers; and develop a framework for addressing the highest... many areas of the country. As this resilient pest has become a nationwide problem affecting hotels...

  11. Insecticide resistance and resistance mechanisms in bed bugs, Cimex spp. (Hemiptera: Cimicidae).

    Science.gov (United States)

    Dang, Kai; Doggett, Stephen L; Veera Singham, G; Lee, Chow-Yang

    2017-06-29

    The worldwide resurgence of bed bugs [both Cimex lectularius L. and Cimex hemipterus (F.)] over the past two decades is believed in large part to be due to the development of insecticide resistance. The transcriptomic and genomic studies since 2010, as well as morphological, biochemical and behavioral studies, have helped insecticide resistance research on bed bugs. Multiple resistance mechanisms, including penetration resistance through thickening or remodelling of the cuticle, metabolic resistance by increased activities of detoxification enzymes (e.g. cytochrome P450 monooxygenases and esterases), and knockdown resistance by kdr mutations, have been experimentally identified as conferring insecticide resistance in bed bugs. Other candidate resistance mechanisms, including behavioral resistance, some types of physiological resistance (e.g. increasing activities of esterases by point mutations, glutathione S-transferase, target site insensitivity including altered AChEs, GABA receptor insensitivity and altered nAChRs), symbiont-mediated resistance and other potential, yet undiscovered mechanisms may exist. This article reviews recent studies of resistance mechanisms and the genes governing insecticide resistance, potential candidate resistance mechanisms, and methods of monitoring insecticide resistance in bed bugs. This article provides an insight into the knowledge essential for the development of both insecticide resistance management (IRM) and integrated pest management (IPM) strategies for successful bed bug management.

  12. Efficacy of an Essential Oil-Based Pesticide for Controlling Bed Bug (Cimex lectularius Infestations in Apartment Buildings

    Directory of Open Access Journals (Sweden)

    Changlu Wang

    2014-11-01

    Full Text Available Bed bugs (Cimex lectularius L. and Cimex hemipterus F. are among the most difficult urban pests to manage. Many essential oil-based bed bug control products that are considered reduced risk to mammals compared to synthetic insect neurotoxins have become commercially available, but their effectiveness as a stand-alone control method is unknown. This study assessed the field efficacy of an essential oil-based bed bug control product (EcoRaider; a.i. 1% geraniol + 1% cedar oil + 2% sodium lauryl sulfate compared to a pyrethroid and neonicotinoid mixture spray (0.075% Temprid SC; a.i. beta-cyfluthrin + imidacloprid. After 12 weeks, the three treatments—EcoRaider, Temprid SC, and EcoRaider + Temprid SC caused 92.5 ± 2.7, 92.9 ± 3.0, and 91.7% ± 2.7% bed bug count reduction, respectively. No significant differences existed in the bed bug reduction among the treatments. Bed bugs were eliminated from only 22% of the treated apartments. Among those still with bed bugs, 76% of the residents did not know bed bugs were present. We documented the residents’ self-control practices and discussed the potential of using essential oil-based insecticides in bed bug management programs to minimize the health risks to building occupants and pets and to slow down the development of insecticide resistance.

  13. Bed Bug Clearinghouse by Type of Resource

    Science.gov (United States)

    This information is to help states, communities, and consumers prevent and control bed bug infestations. These brochures, fact sheets, manuals, posters, checklists, videos, and more provide guidance such as hotel room inspection and pesticide safety.

  14. Effectiveness of a Reduced-Risk Insecticide Based Bed Bug Management Program in Low-Income Housing

    Directory of Open Access Journals (Sweden)

    Narinderpal Singh

    2013-11-01

    Full Text Available Bed bug (Cimex lectularius L. infestations are becoming increasingly common in low-income communities. Once they are introduced, elimination is very difficult. As part of the efforts to develop effective and safe bed bug management programs, we conducted a laboratory study evaluating the efficacy of a reduced-risk insecticide—Alpine aerosol (0.5% dinotefuran. We then conducted a field evaluation of a reduced-risk insecticide based integrated pest management (IPM program in low-income family apartments with young children. In laboratory evaluations, direct spray and 5 min exposure to dry Alpine aerosol residue caused 100.0 ± 0.0 and 91.7 ± 8.3% mortality to bed bug nymphs, respectively. Direct Alpine aerosol spray killed 91.3 ± 4.3% of the eggs. The IPM program included education, steam, bagging infested linens, placing intercepting devices under furniture legs and corners of rooms, applying Alpine aerosol and Alpine dust (0.25% dinotefuran, 95% diatomaceous earth dust, and regularly scheduled monitoring and re-treatment. Nine apartments ranging from 1–1,428 (median: 29 bed bugs based on visual inspection and Climbup interceptor counts were included. Over a 6-month period, an average 172 g insecticide (Alpine aerosol + Alpine dust was used in each apartment, a 96% reduction in pesticide usage compared to chemical only treatment reported in a similar environment. The IPM program resulted in an average of 96.8 ± 2.2% reduction in the number of bed bugs. However, elimination of bed bugs was only achieved in three lightly infested apartments (<30 bed bugs at the beginning. Elimination success was closely correlated with the level of bed bug populations.

  15. Effects of Starvation on Deltamethrin Tolerance in Bed Bugs, Cimex lectularius L. (Hemiptera: Cimicidae

    Directory of Open Access Journals (Sweden)

    Zachary C. DeVries

    2015-01-01

    Full Text Available Bed bugs, Cimex lectularius L., are a major pest in the urban environment. Their presence often results in physical, psychological, and financial distress of homeowners and apartment dwellers. Although many insecticide bioassays have been performed on this pest, little attention has been paid to bed bug feeding status, which is closely linked to metabolism, molting, and mass. Therefore, we evaluated the toxicity of topically applied deltamethrin on insecticide susceptible adult male bed bugs fed 2 d, 9 d, and 21 d prior to testing. When toxicity was evaluated on a “per-bug” basis, there was no difference between 2 d [LD50 = 0.498 (0.316 − 0.692 ng·bug−1] and 9 d [LD50 = 0.572 (0.436 − 0.724 ng·bug−1] starved bugs, while 21 d starved bugs had a significantly lower LD50 [0.221 (0.075 − 0.386 ng·bug−1]. When toxicity was evaluated in terms of body mass, 9 d starved bugs had the highest LD50 values [0.138 (0.102 − 0.176 ng·mg−1], followed by 2 d starved bugs [0.095 (0.060 − 0.134 ng·mg−1], and then 21 d starved bugs [0.058 (0.019–0.102 ng·mg−1]; the LD50 values of 2 d and 9 d starved bugs were significantly different from 21 d starved bugs. These results indicate that feeding status plays an important role in the toxicity of deltamethrin. In addition, the lack of differences between 2 d and 9 d starved bugs indicate that the blood meal itself has little impact on tolerance, but rather it is some physiological change following feeding that confers increased tolerance to bed bugs.

  16. Toxicities of Selected Essential Oils, Silicone Oils, and Paraffin Oil against the Common Bed Bug (Hemiptera: Cimicidae).

    Science.gov (United States)

    Zha, Chen; Wang, Changlu; Li, Andrew

    2018-02-09

    The common bed bug [Cimex lectularius L. (Hemiptera: Cimicidae)] and tropical bed bug [Cimex hemipterus F. (Hemiptera: Cimicidae)] resurged in the United States and many other countries over the past decades. The need for safe and effective bed bug control products propelled the development of numerous 'green insecticides', mostly with essential oils listed as active ingredients. Various inorganic and organic oils also were used for bed bug management. However, there are no published studies on their toxicities against bed bugs. In this study, we screened 18 essential oils, three silicone oils, and paraffin oil (C5-20 paraffins) for their toxicities against bed bugs. All the oils exhibited insecticidal activity in topical assays. Their toxicities varied significantly; all of the evaluated essential oils were less effective than silicone oils and paraffin oil. The LD50 values of the most effective essential oil (blood orange), paraffin oil, and the most effective silicone oil (dodecamethylpentasiloxane) are 0.184 ± 0.018, 0.069 ± 0.012, and 0.036 ± 0.005 mg per bug, respectively. Direct spray of 1% water solution of 3-[hydroxy (polyethyleneoxy) propyl] heptamethyltrisiloxane, the only silicone oil that mixes well with water, resulted in 92% bed bug mortality after 1 d. Results of this study indicate silicone oils and paraffin oil have the potential to be used as safer alternative bed bug control materials. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Stress Tolerance of Bed Bugs: A Review of Factors That Cause Trauma to Cimex lectularius and C. Hemipterus

    Directory of Open Access Journals (Sweden)

    Joshua B. Benoit

    2011-04-01

    Full Text Available Recent emergence of bed bugs (Cimex spp. has prompted a significant expansion of research devoted to this pest. The ability to survive and recover from stress has significant implications on the distribution and survival of insects, and bed bugs are no exception. Research on bed bug stress tolerance has shown considerable progress and necessitates a review on this topic. Bed bugs have an extraordinary ability to resist dehydration between bloodmeals, and this represents a critical factor allowing their prolonged survival when no host is available. High relative humidities are detrimental to bed bugs, leading to reduced survival in comparison to those held at lower relative humidities. Continual exposure of bed bugs, eggs and mobile stages, to temperatures below freezing and short term exposure (=1 h to temperatures below −16 to −18 °C results in mortality. The upper thermal limit for short term exposure of eggs, nymphs and adults is between 40–45 °C for the common (Cimex lectularius and tropical (C. hemipterus bed bugs. Long-term exposure to temperatures above 35 °C results in significant reduction in survival of mobile bed bugs. Eggs for C. lectularius and C. hemipterus are no longer viable when held below 10 °C or above 37 °C throughout embryogenesis. Blood feeding, although necessary for survival and reproduction, is discussed as a stress due to thermal and osmotic fluctuations that result from ingesting a warm bloodmeal from a vertebrate host. Cold, heat, water stress and blood feeding prompted the expression of heat shock proteins (Hsps. Pesticide application is a common human-induced stress for urban pests, and recent studies have documented pesticide resistance in many bed bug populations. High levels of traumatic insemination (mating of bed bugs has been linked to reduced survival and fecundity along with possibly exposing individuals to microbial infections after cuticular penetration by the paramere (=male reproductive organ

  18. Prevention and Control of Bed Bugs in Residences

    Science.gov (United States)

    ... in other rooms, including bathrooms, living rooms and laundry rooms. Look for spots or smears Dark blood ... having the inspection done by a pest control service provider (exterminator). If you find a bed bug, ...

  19. Interactions among Carbon Dioxide, Heat, and Chemical Lures in Attracting the Bed Bug, Cimex lectularius L. (Hemiptera: Cimicidae

    Directory of Open Access Journals (Sweden)

    Narinderpal Singh

    2012-01-01

    Full Text Available Commercial bed bug (Cimex lectularius L. monitors incorporating carbon dioxide (CO2, heat, and chemical lures are being used for detecting bed bugs; however, there are few reported studies on the effectiveness of chemical lures in bed bug monitors and the interactions among chemical lure, CO2, and heat. We screened 12 chemicals for their attraction to bed bugs and evaluated interactions among chemical lures, CO2, and heat. The chemical lure mixture consisting of nonanal, 1-octen-3-ol, spearmint oil, and coriander Egyptian oil was found to be most attractive to bed bugs and significantly increased the trap catches in laboratory bioassays. Adding this chemical lure mixture when CO2 was present increased the trap catches compared with traps baited with CO2 alone, whereas adding heat did not significantly increase trap catches when CO2 was present. Results suggest a combination of chemical lure and CO2 is essential for designing effective bed bug monitors.

  20. Hiring a Pest Management Professional for Bed Bugs

    Science.gov (United States)

    If you hire someone to treat your bed bug infestation, make sure they use Integrated Pest Management (IPM) techniques, check credentials, and know they may need multiple visits, to take apart furniture, and to use vacuums, heat, and pesticides.

  1. Status of Urban Bed Bug Infestations in Southern China: An Analysis of Pest Control Service Records in Shenzhen in 2012 and Dongguan in 2013.

    Science.gov (United States)

    Wang, Lei; Cai, Xuquan; Xu, Yijuan

    2015-01-01

    The recent resurgence of bed bugs (Cimex spp.) in many developed countries has drawn increasing attention worldwide. The status of urban bed bug infestations were investigated in Shenzhen and Dongguan, two major cities in southern Guangdong Province of southern China, based on pest control service records from two different companies (one during 2012 and another during 2013). The results showed that Shenzhen and Dongguan have a severe problem with bed bug infestations: the control of bed bugs is a constant concern, except during the winter. In Shenzhen, a similar number of premises were treated for bed bugs in central business districts and suburban districts. However, in Dongguan, more premises were treated for bed bugs in suburban districts than in central business districts. The treatment rate for worker sleeping quarters, apartments, hotel, and private houses in Shenzhen was 53.8, 43.0, 1.9, and 1.3%, respectively. The percentage of treated rooms was 56.1% for worker sleeping quarters and 91.1% for apartments. In Dongguan, the treatment rate for worker sleeping quarters, apartments, hotel, and private houses was 90.0, 10.0, 0.0, and 0.0%, respectively. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Unique features of a global human ectoparasite identified through sequencing of the bed bug genome.

    Science.gov (United States)

    Benoit, Joshua B; Adelman, Zach N; Reinhardt, Klaus; Dolan, Amanda; Poelchau, Monica; Jennings, Emily C; Szuter, Elise M; Hagan, Richard W; Gujar, Hemant; Shukla, Jayendra Nath; Zhu, Fang; Mohan, M; Nelson, David R; Rosendale, Andrew J; Derst, Christian; Resnik, Valentina; Wernig, Sebastian; Menegazzi, Pamela; Wegener, Christian; Peschel, Nicolai; Hendershot, Jacob M; Blenau, Wolfgang; Predel, Reinhard; Johnston, Paul R; Ioannidis, Panagiotis; Waterhouse, Robert M; Nauen, Ralf; Schorn, Corinna; Ott, Mark-Christoph; Maiwald, Frank; Johnston, J Spencer; Gondhalekar, Ameya D; Scharf, Michael E; Peterson, Brittany F; Raje, Kapil R; Hottel, Benjamin A; Armisén, David; Crumière, Antonin Jean Johan; Refki, Peter Nagui; Santos, Maria Emilia; Sghaier, Essia; Viala, Sèverine; Khila, Abderrahman; Ahn, Seung-Joon; Childers, Christopher; Lee, Chien-Yueh; Lin, Han; Hughes, Daniel S T; Duncan, Elizabeth J; Murali, Shwetha C; Qu, Jiaxin; Dugan, Shannon; Lee, Sandra L; Chao, Hsu; Dinh, Huyen; Han, Yi; Doddapaneni, Harshavardhan; Worley, Kim C; Muzny, Donna M; Wheeler, David; Panfilio, Kristen A; Vargas Jentzsch, Iris M; Vargo, Edward L; Booth, Warren; Friedrich, Markus; Weirauch, Matthew T; Anderson, Michelle A E; Jones, Jeffery W; Mittapalli, Omprakash; Zhao, Chaoyang; Zhou, Jing-Jiang; Evans, Jay D; Attardo, Geoffrey M; Robertson, Hugh M; Zdobnov, Evgeny M; Ribeiro, Jose M C; Gibbs, Richard A; Werren, John H; Palli, Subba R; Schal, Coby; Richards, Stephen

    2016-02-02

    The bed bug, Cimex lectularius, has re-established itself as a ubiquitous human ectoparasite throughout much of the world during the past two decades. This global resurgence is likely linked to increased international travel and commerce in addition to widespread insecticide resistance. Analyses of the C. lectularius sequenced genome (650 Mb) and 14,220 predicted protein-coding genes provide a comprehensive representation of genes that are linked to traumatic insemination, a reduced chemosensory repertoire of genes related to obligate hematophagy, host-symbiont interactions, and several mechanisms of insecticide resistance. In addition, we document the presence of multiple putative lateral gene transfer events. Genome sequencing and annotation establish a solid foundation for future research on mechanisms of insecticide resistance, human-bed bug and symbiont-bed bug associations, and unique features of bed bug biology that contribute to the unprecedented success of C. lectularius as a human ectoparasite.

  3. Unique features of a global human ectoparasite identified through sequencing of the bed bug genome

    Science.gov (United States)

    Benoit, Joshua B.; Adelman, Zach N.; Reinhardt, Klaus; Dolan, Amanda; Poelchau, Monica; Jennings, Emily C.; Szuter, Elise M.; Hagan, Richard W.; Gujar, Hemant; Shukla, Jayendra Nath; Zhu, Fang; Mohan, M.; Nelson, David R.; Rosendale, Andrew J.; Derst, Christian; Resnik, Valentina; Wernig, Sebastian; Menegazzi, Pamela; Wegener, Christian; Peschel, Nicolai; Hendershot, Jacob M.; Blenau, Wolfgang; Predel, Reinhard; Johnston, Paul R.; Ioannidis, Panagiotis; Waterhouse, Robert M.; Nauen, Ralf; Schorn, Corinna; Ott, Mark-Christoph; Maiwald, Frank; Johnston, J. Spencer; Gondhalekar, Ameya D.; Scharf, Michael E.; Peterson, Brittany F.; Raje, Kapil R.; Hottel, Benjamin A.; Armisén, David; Crumière, Antonin Jean Johan; Refki, Peter Nagui; Santos, Maria Emilia; Sghaier, Essia; Viala, Sèverine; Khila, Abderrahman; Ahn, Seung-Joon; Childers, Christopher; Lee, Chien-Yueh; Lin, Han; Hughes, Daniel S. T.; Duncan, Elizabeth J.; Murali, Shwetha C.; Qu, Jiaxin; Dugan, Shannon; Lee, Sandra L.; Chao, Hsu; Dinh, Huyen; Han, Yi; Doddapaneni, Harshavardhan; Worley, Kim C.; Muzny, Donna M.; Wheeler, David; Panfilio, Kristen A.; Vargas Jentzsch, Iris M.; Vargo, Edward L.; Booth, Warren; Friedrich, Markus; Weirauch, Matthew T.; Anderson, Michelle A. E.; Jones, Jeffery W.; Mittapalli, Omprakash; Zhao, Chaoyang; Zhou, Jing-Jiang; Evans, Jay D.; Attardo, Geoffrey M.; Robertson, Hugh M.; Zdobnov, Evgeny M.; Ribeiro, Jose M. C.; Gibbs, Richard A.; Werren, John H.; Palli, Subba R.; Schal, Coby; Richards, Stephen

    2016-01-01

    The bed bug, Cimex lectularius, has re-established itself as a ubiquitous human ectoparasite throughout much of the world during the past two decades. This global resurgence is likely linked to increased international travel and commerce in addition to widespread insecticide resistance. Analyses of the C. lectularius sequenced genome (650 Mb) and 14,220 predicted protein-coding genes provide a comprehensive representation of genes that are linked to traumatic insemination, a reduced chemosensory repertoire of genes related to obligate hematophagy, host–symbiont interactions, and several mechanisms of insecticide resistance. In addition, we document the presence of multiple putative lateral gene transfer events. Genome sequencing and annotation establish a solid foundation for future research on mechanisms of insecticide resistance, human–bed bug and symbiont–bed bug associations, and unique features of bed bug biology that contribute to the unprecedented success of C. lectularius as a human ectoparasite. PMID:26836814

  4. Evaluation of cimi-shield knock-out bed bug eliminator against house fly (Musca domestica) adults.

    Science.gov (United States)

    Cimi-Shield Knock-Out (CSKO) Bed Bug Eliminator is a green treatment labeled for use against bed bugs, carpet beetles, ants, roaches, fleas, ticks, silverfish, millipedes and centipedes. The active ingredient is soybean oil. If CSKO is formulated according to label instructions and sprayed directly ...

  5. Protecting Yourself from Bed Bugs in Public Places

    Science.gov (United States)

    ... office. By reducing clutter in your workplace or school, you provide fewer places for the bed bugs to hide and fewer opportunities for them to hitchhike to your home. Keep your ... office or school, consider storing your belongings in a plastic bin. ...

  6. Bullous reactions to bed bug bites reflect cutaneous vasculitis

    Science.gov (United States)

    This study evaluates bullous cutaneous reactions and sequential histopathology in an individual sensitized to bed bug bites in an effort to better understand the allergic response and histology associated with these bites. There was a progression of the inflammatory response across time ranging from...

  7. Climbing ability of teneral and sclerotized adult bed bugs and assessment of adhesive properties of the exoskeletal fluid using atomic force microscopy.

    Directory of Open Access Journals (Sweden)

    Kevin R Hinson

    Full Text Available We observed that teneral adults (72 h, and sclerotized group 2 (S2 bed bugs (n = 30, height climbed = 2.64 cm at >72 h post molt. When heights from all climbing events were summed, teneral bed bugs (650.8 cm climbed differed significantly (P< 0.01 from recently sclerotized (82 cm climbed and sclerotized (group 1 = 104.6 cm climbed, group 2 = 107.8 cm climbed bed bugs. These findings suggested that the external surface of teneral bed bug exoskeletons possess an adhesive property. Using atomic force microscopy (AFM, we found that adhesion force of an exoskeletal (presumably molting fluid decreased almost five-fold from 88 to 17 nN within an hour of molting. Our findings may have implications for laboratory safety and the effectiveness of bed bug traps, barriers, and biomimetic-based adhesives.

  8. Bed Bug (Cimex lectularius L. Population Composition as Determined by Baited Traps

    Directory of Open Access Journals (Sweden)

    Elizabeth J. Schaafsma

    2012-04-01

    Full Text Available Two established field populations of bed bugs were sampled using host-mimicking traps baited with a combination of CO2, heat and a synthetic kairomone. The proportion of first instar nymphs (between 52% and 78% of all captured insects was significantly higher than reported in previous studies, which had employed different sampling methods. The proportion of adults was correspondingly much lower than previously reported, between 5% and 7% of total capture. As many as 120 bed bugs were captured in a single trap in one night; the variation in catches between sampling locations within the same room and between days at the same location indicates that multiple nights of trapping may be required to obtain an accurate representation of population structure.

  9. Comparison of ingestion and topical application of insecticides against the common bed bug, Cimex lectularius (Hemiptera: Cimicidae)

    Science.gov (United States)

    Sierras, Angela; Schal, Coby

    2016-01-01

    Background The global prevalence of Cimex lectularius infestations has challenged current intervention efforts, as pyrethroid resistance has become ubiquitous, availability of labeled insecticides for bed bugs is limited, and non-chemical treatment options, such as heat, are often unaffordable. We evaluated representative insecticides toward the goal of developing a novel, ingestible liquid bait for hematophagous arthropods. Results LC50 values were estimated for adult males and first instar nymphs of an insecticide-susceptible strain for abamectin, clothianidin, fipronil and indoxacarb, after ingestion from an in vitro feeder. LD50 values were calculated based on the ingested blood volume. Ingested abamectin, clothianidin and fipronil caused rapid mortality in both life stages. Fipronil was ∼43-fold more effective by ingestion than by topical application. Indoxacarb and its bioactive metabolite decarbomethoxyllated JW062 (DCJW) were ineffective at causing bed bug mortality even at concentrations as high as 1000 ng mL−1 blood. Conclusions Fipronil, clothianidin and abamectin have potential for being incorporated into a liquid bait for bed bug control; indoxacarb and DCJW were not effective. Bed bugs are a good candidate for an ingestible liquid bait because systemic formulations generally require less active ingredient than residual sprays, they remain contained and more effectively target hematophagous arthropods. PMID:27766740

  10. RNA interference of NADPH-cytochrome P450 reductase results in reduced insecticide resistance in the bed bug, Cimex lectularius.

    Science.gov (United States)

    Zhu, Fang; Sams, Sarah; Moural, Tim; Haynes, Kenneth F; Potter, Michael F; Palli, Subba R

    2012-01-01

    NADPH-cytochrome P450 reductase (CPR) plays a central role in cytochrome P450 action. The genes coding for P450s are not yet fully identified in the bed bug, Cimex lectularius. Hence, we decided to clone cDNA and knockdown the expression of the gene coding for CPR which is suggested to be required for the function of all P450s to determine whether or not P450s are involved in resistance of bed bugs to insecticides. The full length Cimex lectularius CPR (ClCPR) cDNA was isolated from a deltamethrin resistant bed bug population (CIN-1) using a combined PCR strategy. Bioinformatics and in silico modeling were employed to identify three conserved binding domains (FMN, FAD, NADP), a FAD binding motif, and the catalytic residues. The critical amino acids involved in FMN, FAD, NADP binding and their putative functions were also analyzed. No signal peptide but a membrane anchor domain with 21 amino acids which facilitates the localization of ClCPR on the endoplasmic reticulum was identified in ClCPR protein. Phylogenetic analysis showed that ClCPR is closer to the CPR from the body louse, Pediculus humanus corporis than to the CPRs from the other insect species studied. The ClCPR gene was ubiquitously expressed in all tissues tested but showed an increase in expression as immature stages develop into adults. We exploited the traumatic insemination mechanism of bed bugs to inject dsRNA and successfully knockdown the expression of the gene coding for ClCPR. Suppression of the ClCPR expression increased susceptibility to deltamethrin in resistant populations but not in the susceptible population of bed bugs. These data suggest that P450-mediated metabolic detoxification may serve as one of the resistance mechanisms in bed bugs.

  11. Toxicity of selected essential oils, silicone oils, and paraffino oil against the common bed bug, cimex lectularius L. (Hemiptera: Cimicidae)

    Science.gov (United States)

    The common bed bug (Cimex lectularius L.) resurged in the U.S. and many other countries over the past decade. The need for safe and effective bed bug control products propelled the development of numerous “green pesticides”, mostly with essential oils listed as active ingredients. Various inorganic ...

  12. Metabolic Resistance in Bed Bugs

    Directory of Open Access Journals (Sweden)

    Omprakash Mittapalli

    2011-03-01

    Full Text Available Blood-feeding insects have evolved resistance to various insecticides (organochlorines, pyrethroids, carbamates, etc. through gene mutations and increased metabolism. Bed bugs (Cimex lectularius are hematophagous ectoparasites that are poised to become one of the major pests in households throughout the United States. Currently, C. lectularius has attained a high global impact status due to its sudden and rampant resurgence. Resistance to pesticides is one factor implicated in this phenomenon. Although much emphasis has been placed on target sensitivity, little to no knowledge is available on the role of key metabolic players (e.g., cytochrome P450s and glutathione S-transferases towards pesticide resistance in C. lectularius. In this review, we discuss different modes of resistance (target sensitivity, penetration resistance, behavioral resistance, and metabolic resistance with more emphasis on metabolic resistance.

  13. Field Study of the Comparative Efficacy of Three Pyrethroid/Neonicotinoid Mixture Products for the Control of the Common Bed Bug, Cimex lectularius

    Directory of Open Access Journals (Sweden)

    Changlu Wang

    2015-03-01

    Full Text Available Three insecticide mixtures that contain two classes of insecticides (pyrethroid and neonicotinoid were recently developed to control bed bugs. We evaluated three integrated bed bug management strategies in apartments, each using the same non-chemical control methods and one of the three insecticide mixture products: Tandem (lambda-cyhalothrin + thiamethoxam, Temprid SC (beta-cyfluthrin + imidacloprid, and Transport Mikron (bifenthrin + acetamiprid. No insecticides were applied in the Control apartments. In all apartments, we installed vinyl mattress encasements (if not already present and applied steam to beds and other infested upholstered furniture. Insecticide sprays were applied in the three treatments. Each treatment and the Control included 8–10 occupied apartments. Re-treatment was conducted during biweekly inspections if necessary. After eight weeks, the mean (± SEM bed bug count reduction in the Tandem, Temprid SC, Transport Mikron, and Control was 89 ± 9, 87 ± 6, 98 ± 1, and 23 ± 54%, respectively. Only Tandem and Transport Mikron treatments resulted in significantly higher population reduction than the Control at eight weeks. There were no significant differences in mean percent reduction among the three treatments (Tandem, Temprid SC, Transport Mikron at eight weeks. Tandem spray caused significantly faster bed bug reduction than Temprid SC spray and Transport Mikron spray.

  14. Detection of Reduced Susceptibility to Chlorfenapyr- and Bifenthrin-Containing Products in Field Populations of the Bed Bug (Hemiptera: Cimicidae).

    Science.gov (United States)

    Ashbrook, Aaron R; Scharf, Michael E; Bennett, Gary W; Gondhalekar, Ameya D

    2017-06-01

    Insecticide resistance is a major impediment for effective control of Cimex lectularius L. Previous resistance detection studies with bed bugs have focused on certain pyrethroid, neonicotinoid, organochlorine, organophosphate, and carbamate insecticides. Within the pyrethroid class, resistance studies have mostly been limited to deltamethrin, lambda-cyhalothrin, and alpha- and beta-cyfluthrin. The goal of this study was to develop diagnostic concentration bioassays for assessing bed bug susceptibility levels to chlorfenapyr- and bifenthrin-containing products. First, glass vial and filter paper bioassay methods were compared for their utility in susceptibility monitoring. Statistical comparison of toxicity data between bioassays indicated that the vial assay was less confounded by assay susbtrate effects, required less insecticide, and was faster, especially for chlorfenapyr. Next, using vial diagnostic concentrations (LC99) for each insecticide, 10 laboratory-adapted field strains and the Harlan lab-susceptible strain were screened for susceptibility to chlorfenapyr and bifenthrin. The results of this study reveal recent bed bug susceptibility levels to certain chlorfenapyr- and bifenthrin-containing products. Reduced susceptibility was detected in three and five field strains to chlorfenapyr and bifenthrin, respectively. Detection of reduced susceptibility suggests that certain strains may be segregating toward greater chlorfenapyr and bifenthrin resistance. These results merit continuous resistance monitoring efforts to detect chlorfenapyr and bifenthrin susceptibility shifts. Additionally, to reduce insecticide selection pressures and delay resistance development, adoption of integrated bed bug control strategies that combine chemical and nonchemical methods is recommended. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Laboratory efficacy of mycoparasitic fungi (Aspergillus tubingensis and Trichoderma harzianum against tropical bed bugs (Cimex hemipterus (Hemiptera: Cimicidae

    Directory of Open Access Journals (Sweden)

    Zulaikha Zahran

    2017-04-01

    Conclusions: Approaches to the bed bugs treatment should be explored in-depth using a natural biological agent like fungus especially A. tubingensis to reduce this pest population, in order to replace chemical methods.

  16. New Introductions, Spread of Existing Matrilines, and High Rates of Pyrethroid Resistance Result in Chronic Infestations of Bed Bugs (Cimex lectularius L. in Lower-Income Housing.

    Directory of Open Access Journals (Sweden)

    Ronald W Raab

    Full Text Available Infestations of the common bed bug (Cimex lectularius L. have increased substantially in the United States in the past 10-15 years. The housing authority in Harrisonburg, Virginia, conducts heat-treatments after bed bugs are detected in a lower-income housing complex, by treating each infested unit at 60°C for 4-6 hours. However, a high frequency of recurrent infestations called into question the efficacy of this strategy. Genetic analysis using Bayesian clustering of polymorphic microsatellite loci from 123 bed bugs collected from 23 units from May 2012 to April 2013 in one building indicated that (a 16/21 (73% infestations were genetically similar, suggesting ineffective heat-treatments or reintroductions from within the building or from a common external source, followed by local spread of existing populations; and (b up to 5 of the infestations represented new genotypes, indicating that 5 new populations were introduced into this building in one year, assuming they were not missed in earlier screens. There was little to no gene flow among the 8 genetic clusters identified in the building. Bed bugs in the U.S. often possess one or both point mutations in the voltage-gated sodium channel, termed knockdown resistance (kdr, from valine to leucine (V419L and leucine to isoleucine (L925I that confer target-site resistance against pyrethroid insecticides. We found that 48/121 (40% bed bugs were homozygous for both kdr mutations (L419/I925, and a further 59% possessed at least one of the kdr mutations. We conclude that ineffective heat treatments, new introductions, reintroductions and local spread, and an exceptionally high frequency of pyrethroid resistance are responsible for chronic infestations in lower-income housing. Because heat treatments fail to protect from reintroductions, and pesticide use has not decreased the frequency of infestations, preventing new introductions and early detection are the most effective strategies to avoid bed bug

  17. Exposure of bed bugs to metarhizium anisopliae, and the effect of defensive secretions on fungal growth in vitro

    Science.gov (United States)

    Bed bugs Cimex lectularius were treated with conidia of the entomopathogenic fungus Metarhizium anisopliae by topical, spray, and contact exposure. One week post-exposure, inconsistent mortalities were observed, averaging 30% across all treatment groups and replicates. Microscopic examination of top...

  18. Molecular markers reveal infestation dynamics of the bed bug (Hemiptera: Cimicidae) within apartment buildings.

    Science.gov (United States)

    Booth, Warren; Saenz, Virna L; Santangelo, Richard G; Wang, Changlu; Schal, Coby; Vargo, Edward L

    2012-05-01

    The bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), has experienced an extraordinary global resurgence in recent years, the reasons for which remain poorly understood. Once considered a pest of lower socioeconomic classes, bed bugs are now found extensively across all residential settings, with widespread infestations established in multiapartment buildings. Within such buildings, understanding the population genetic structure and patterns of dispersal may prove critical to the development of effective control strategies. Here, we describe the development of 24 high-resolution microsatellite markers through next generation 454 pyrosequencing and their application to elucidate infestation dynamics within three multistory apartment buildings in the United States. Results reveal contrasting characteristics potentially representative of geographic or locale differences. In Raleigh, NC, an infestation within an apartment building seemed to have started from a single introduction followed by extensive spread. In Jersey City, NJ, two or more introductions followed by spread are evident in two buildings. Populations within single apartments in all buildings were characterized by high levels of relatedness and low levels of diversity, indicative of foundation from small, genetically depauperate propagules. Regardless of the number of unique introductions, genetic data indicate that spread within buildings is extensive, supporting both active and human-mediated dispersal within and between adjacent rooms or apartments spanning multiple floors.

  19. Molecular characterization of Wolbachia infection in bed bugs (Cimex lectularius collected from several localities in France

    Directory of Open Access Journals (Sweden)

    Akhoundi Mohammad

    2016-01-01

    Full Text Available Wolbachia symbionts are maternally inherited intracellular bacteria that have been detected in numerous insects including bed bugs. The objective of this study, the first epidemiological study in Europe, was to screen Wolbachia infection among Cimex lectularius collected in the field, using PCR targeting the surface protein gene (wsp, and to compare obtained Wolbachia strains with those reported from laboratory colonies of C. lectularius as well as other Wolbachia groups. For this purpose, 284 bed bug specimens were caught and studied from eight different regions of France including the suburbs of Paris, Bouches-du-Rhône, Lot-et-Garonne, and five localities in Alpes-Maritimes. Among the samples, 166 were adults and the remaining 118 were considered nymphs. In all, 47 out of 118 nymphs (40% and 61 out of 166 adults (37% were found positive on wsp screening. Among the positive cases, 10 samples were selected randomly for sequencing. The sequences had 100% homology with wsp sequences belonging to the F-supergroup strains of Wolbachia. Therefore, we confirm the similarity of Wolbachia strains detected in this epidemiological study to Wolbachia spp. reported from laboratory colonies of C. lectularius.

  20. Insecticide Resistance in Eggs and First Instars of the Bed Bug, Cimex lectularius (Hemiptera: Cimicidae

    Directory of Open Access Journals (Sweden)

    Brittany E. Campbell

    2015-01-01

    Full Text Available Two strains of the common bed bug, Cimex lectularius L., eggs and first instars collected from pyrethroid-resistant adults were evaluated for insecticide resistance and compared to a susceptible strain. Dose-response bioassays were conducted using two insecticide formulations (Temprid: imidacloprid/β-cyfluthrin, and Transport: acetamiprid/ bifenthrin. The lethal concentration (LC50 for the two resistant egg strains exposed to imidacloprid/β-cyfluthrin ranged from 3 to 5-fold higher than susceptible strain eggs. Resistant strain eggs dipped into formulations of acetamiprid/bifenthrin had LC50 values which were significantly greater (39 to 1,080-fold than susceptible strain eggs. Similar to eggs, resistant strain first instars exposed to residual applications of imidacloprid/β-cyfluthrin had LC50 values ranging from 121 to 493-fold greater than susceptible strain first instars. When resistant strain first instars were treated with acetamiprid/bifenthrin, they had LC50 values that were 99 to >1,900-fold greater than susceptible strain first instars. To determine differences between egg and first instar resistance, stage resistance ratios (SRR were compared between the two stages. There was little difference between the egg and first instar stages, indicated by small SRR values ranging from 1.1 to 10.0. This study suggests that insecticide resistance is expressed early during bed bug development.

  1. Egg Hatch Rate and Nymphal Survival of the Bed Bug (Hemiptera: Cimicidae) After Exposure to Insecticide Sprays.

    Science.gov (United States)

    Hinson, K R; Benson, E P; Zungoli, P A; Bridges, W C; Ellis, B R

    2016-12-01

    Few studies have addressed the efficacy of insecticides used against eggs and first-instar nymphs of the bed bug, Cimex lectularius L. (Hemiptera: Cimicidae). Insect eggs are often resistant to insecticides; therefore, information on which products are effective is important. We evaluated the efficacy of four commonly used insecticide sprays applied directly to bed bug eggs. We also evaluated the efficacy of these insecticides to first-instar nymphs exposed to residuals resulting from directly spraying eggs. Temprid SC (beta-cyfluthrin, imidacloprid) was the most effective insecticide at preventing egg hatch (13% hatch rate) for pyrethroid-resistant, field-strain (Jersey City) bed bugs compared with a control (water [99% hatch rate]), Bedlam (MGK-264, sumithrin [84% hatch rate]), Demand CS (lambda-cyhalothrin [91% hatch rate]), and Phantom SC (chlorfenapyr [95% hatch rate]). Demand CS and Temprid SC were most effective at preventing egg hatch (0%) for an insecticide-susceptible (Harold Harlan) strain, followed by Bedlam (28%). Phantom SC produced a hatch rate similar to the control (97% and 96%, respectively). Harold Harlan-strain nymphs showed 100% survival for the control but 0% survival for Bedlam and Phantom SC. Jersey City-strain nymphs showed 100% survival for the control, 99% survival for Bedlam, 0% survival for Demand CS, 4% survival for Phantom SC, and 38% survival for Temprid SC. Demand CS was less effective at preventing hatch (91% hatch rate) of Jersey City-strain nymphs but was the only product to kill all nymphs (0% survival). One of the least effective products for preventing Jersey City-strain egg hatch (Phantom SC, 95% hatch rate) was the second most effective at killing nymphs, leaving only six of 141 alive. These findings indicate that survival of directly sprayed eggs and residually exposed, first-instar nymphs varies by strain, life stage, and product used. © The Authors 2016. Published by Oxford University Press on behalf of Entomological

  2. Bed Bugs Appearance and Life Cycle

    Science.gov (United States)

    Identify these bugs accurately, from egg to nymph to adult. Adults are about the size of an apple seed, brown and oval-shaped, and either flat or balloon-like depending on how recently fed. Nymphs are a bit smaller and translucent or whitish yellow.

  3. Efficacy of Selected Insecticide Sprays and Aerosols against the Common Bed Bug, Cimex lectularius (Hemiptera: Cimicidae

    Directory of Open Access Journals (Sweden)

    Changlu Wang

    2016-01-01

    Full Text Available We evaluated the residual efficacy of four liquid sprays and four ready-to-use aerosols that are commonly used in the U.S. against a field-collected bed bug, Cimex lectularius L., strain with moderate resistance level to pyrethroids. The four liquid sprays were: Tandem (0.1% thiamethoxam, 0.03% lambda-cyhalothrin, Temprid SC (0.05% imidacloprid, 0.025% cyfluthrin, Transport GHP (0.05% acetamiprid, 0.06% bifenthrin, and Demand CS (0.03% lambda-cyhalothrin. The four aerosols were: Alpine (0.5% dinotefuran, Bedlam (0.4% sumithrin, 1.6% MGK 264, Bedlam Plus (0.4% sumithrin, 1% MGK 264, 0.05% imidacloprid, and Phantom (0.5% chlorfenapyr. Bed bugs were confined for 4 h to treated substrates (aged 24 h. Four substrates were tested: fabric, unpainted wood, painted wood, and vinyl. Bedlam, Demand CS, and Temprid SC resulted in ≤70% mortality on all tested substrates. Among the other five products, substrate type significantly affected their residual efficacy, except for Transport GHP, which caused ≥89.7% mortality regardless of the substrate. The effect of exposure time (5 min, 4 h, and 24 h on the efficacy of Transport GHP and Phantom aerosol also was evaluated. A 4 h continuous exposure to Phantom aerosol or Transport GHP residue caused similar mortality to 24 h exposure and higher mortality than 5 min exposure.

  4. Inhibition of the entomopathogenic fungus Metarhizium anisopliae in vitro by the bed bug defensive secretions (E)-2-hexenal and (E)-2-octenal

    Science.gov (United States)

    The two major aldehydes (E)-2-hexenal and (E)-2-octenal emitted as defensive secretions by bed bugs Cimex lectularius L. (Hemiptera: Cimicidae), inhibit the in vitro growth of Metarhizium anisopliae (Metsch.) Sokorin (Hypocreales: Clavicipitaceae). These chemicals inhibit fungal growth by direct con...

  5. Variability Bugs:

    DEFF Research Database (Denmark)

    Melo, Jean

    . Although many researchers suggest that preprocessor-based variability amplifies maintenance problems, there is little to no hard evidence on how actually variability affects programs and programmers. Specifically, how does variability affect programmers during maintenance tasks (bug finding in particular......)? How much harder is it to debug a program as variability increases? How do developers debug programs with variability? In what ways does variability affect bugs? In this Ph.D. thesis, I set off to address such issues through different perspectives using empirical research (based on controlled...... experiments) in order to understand quantitatively and qualitatively the impact of variability on programmers at bug finding and on buggy programs. From the program (and bug) perspective, the results show that variability is ubiquitous. There appears to be no specific nature of variability bugs that could...

  6. A review of data on laboratory colonies of bed bugs (Cimicidae, an insect of emerging medical relevance

    Directory of Open Access Journals (Sweden)

    Cannet Arnaud

    2015-01-01

    Full Text Available Cimicidae are hematophagous Heteroptera, feeding on human blood, that have been the subject of significant medical investigation. In particular, they have been colonized under laboratory conditions to study their medical relevance. Laboratory colonization of these bugs is a multifactorial phenomenon. Our goal was to conduct a comparative literature review to classify the published data, demonstrating preferred bed bug colony conditions. We show that physical factors including temperature, relative humidity and photoperiod, and physiological factors such as type and frequency of blood meals play important roles in laboratory colonies. Any change in these factors produces changes in life-cycle duration. Temperature and blood meal are the most important factors, with a marked impact on the life-cycle of laboratory populations, depending on the species. A wide range of temperatures (15–34 °C and relative humidity (46–75% with an average of 25 °C and 59% were found for these colonies. Two widely used blood sources for the colonies were rabbits and humans.

  7. Nymphs of the common bed bug (Cimex lectularius produce anti-aphrodisiac defence against conspecific males

    Directory of Open Access Journals (Sweden)

    Harraca Vincent

    2010-09-01

    Full Text Available Abstract Background Abdominal wounding by traumatic insemination and the lack of a long distance attraction pheromone set the scene for unusual sexual signalling systems. Male bed bugs (Cimex lectularius mount any large, newly fed individual in an attempt to mate. Last instar nymphs overlap in size with mature females, which make them a potential target for interested males. However, nymphs lack the female's specific mating adaptations and may be severely injured by the abdominal wounding. We, therefore, hypothesized that nymphs emit chemical deterrents that act as an honest status signal, which prevents nymph sexual harassment and indirectly reduces energy costs for males. Results Behavioural mating assays showed that males mount nymphs significantly shorter time compared to females, although initial mounting preference was the same. In support of our hypothesis, nymphs experienced the same percentage of mating with sperm transfer as females if they were unable to emit (E-2-hexenal, (E-2-octenal 4-oxo-(E-2-hexenal and 4-oxo-(E-2-octenal, from their dorsal abdominal glands. We report that the aldehydes and 4-oxo-(E-2-hexenal are detected by olfactory receptor neurons housed in smooth and grooved peg sensilla, respectively, on the adult antennae, at biologically relevant concentrations. Behavioural experiments showed that application of 4-oxo-(E-2-hexenal or the two aldehydes at a nymph-emitted ratio, to a male/female pair during mounting initiation, decreased mating frequency to a rate comparable to that of a male/nymph pair. Conclusions By combining behavioural and sensory studies, we show that the nymph-specific alarm pheromone plays an important role in intra-specific communication in the common bed bug. Alarm pheromones are commonly looked upon as a system in predator/prey communication, but here we show that alarm pheromones may be used as multipurpose signals such as decreasing the risk of nymphal mating by males. See commentary: http

  8. IDENTIFIKASI DUPLIKASI LAPORAN BUG PADA REPOSITORI LAPORAN BUG UNTUK MENGHASILKAN SARAN RESOLUSI BUG PERANGKAT LUNAK

    Directory of Open Access Journals (Sweden)

    Sugiyanto Sugiyanto

    2013-07-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Repositori laporan bug perangkat lunak sebenarnya menyediakan informasi dan saran resolusi bug tertentu yang dapat digunakan untuk memperbaiki bug yang terjadi pada tahap perbaikan perangkat lunak. Pengembang dapat mencari saran resolusi bug perangkat lunak tertentu dengan mengidentifikasi duplikasi bug pada repositori laporan bug perangkat lunak. Penelitian ini mengusulkan sistem identifikasi duplikasi laporan bug pada repositori laporan bug untuk menghasilkan saran resolusi bug perangkat lunak menggunakan teknik pendekatan temu kembali informasi. Pengembang dapat menemukan informasi alasan kegagalan perangkat lunak dan memperoleh saran resolusi untuk memperbaiki bug tersebut. Hasil penelitian ini menunjukkan bahwa teknik pendekatan temu kembali informasi dapat digunakan untuk mengidentifikasi duplikasi laporan bug pada repositori laporan bug untuk menghasilkan saran resolusi bug perangkat lunak.

  9. Top Ten Bed Bug Tips

    Science.gov (United States)

    ... Directory Planning, Budget and Results Jobs and Internships Headquarters Offices Regional Offices Labs and Research Centers Bed ... you hire an expert, be sure it’s a company with a good reputation and request that it ...

  10. The BUG BITBUS Universal Gateway

    International Nuclear Information System (INIS)

    Nawrocki, G.

    1996-01-01

    The BITBUS Universal Gateway (BUG) provides a unique, cost effective solution to many different computer interface problems. Each BUG node, utilizing ''on board'' intelligence, has the ability to provide a communication link between BITBUS protocol and other computer-signal interfaces. Among them, IEEE-488, RS232, and raw analog and binary signal 1/0. BITBUS is a multidrop, multinode link with the ability to communicate over great distances. By using this method of signal transfer, along with the communication conversion ability of the BUG, one could accomplish such things as the ability to run IEEE-488 instruments over great distances, extend a multidrop links to RS232 instruments, and provide a convenient interface point for remote analog and binary 1/0 signals, all on one homogeneous network. The BUG not only provides this through the wired ''twisted pair'' standard of BITBUS, but extends the ability to fiber optic communications for signal transfer over extreme distances and through electrically ''noisy'' environments

  11. Mining Bug Databases for Unidentified Software Vulnerabilities

    Energy Technology Data Exchange (ETDEWEB)

    Dumidu Wijayasekara; Milos Manic; Jason Wright; Miles McQueen

    2012-06-01

    Identifying software vulnerabilities is becoming more important as critical and sensitive systems increasingly rely on complex software systems. It has been suggested in previous work that some bugs are only identified as vulnerabilities long after the bug has been made public. These vulnerabilities are known as hidden impact vulnerabilities. This paper discusses the feasibility and necessity to mine common publicly available bug databases for vulnerabilities that are yet to be identified. We present bug database analysis of two well known and frequently used software packages, namely Linux kernel and MySQL. It is shown that for both Linux and MySQL, a significant portion of vulnerabilities that were discovered for the time period from January 2006 to April 2011 were hidden impact vulnerabilities. It is also shown that the percentage of hidden impact vulnerabilities has increased in the last two years, for both software packages. We then propose an improved hidden impact vulnerability identification methodology based on text mining bug databases, and conclude by discussing a few potential problems faced by such a classifier.

  12. Effective Bug Finding

    DEFF Research Database (Denmark)

    Rivas, Iago Abal

    Lightweight bug finders (also known as code scanners) are becoming popular, they scale well and can find simple yet common programming errors. It is now considered a good practice to integrate these tools as part of your development process. The Linux project, for instance, has an automated testing...... service, known as the Kbuild robot, that runs a few of these code scanners. In this project, I have carefully studied tens of historical Linux bugs, and I have found that many of these bugs, despite being conceptually simple, were not caught by any code scanning tool. The reason is that, by design, code...... by matching temporal bug-patterns against the control-flow graph of this program abstraction. I have implemented a proof-of-concept bug finder based on this technique, EBA, and confirmed that it is both scalable and effective at finding bugs. On a benchmark of historical Linux double-lock bugs, EBA was able...

  13. Four bugs on a rectangle

    KAUST Repository

    Chapman, S. J.

    2010-11-10

    The idealized mathematical problem of four bugs in cyclic pursuit starting from a 2-by-1 rectangle is considered, and asymptotic formulas are derived to describe the motion. In contrast to the famous case of four bugs on a square, here the trajectories quickly freeze to essentially one dimension. After the first rotation about the centre point, the scale of the configuration has shrunk by a factor of 10427907250, and this number is then exponentiated four more times with each successive cycle. Relations to Knuth\\'s double-arrow notation and level-index arithmetic are discussed. This journal is © 2011 The Royal Society.

  14. Effective Bug Finding

    DEFF Research Database (Denmark)

    Rivas, Iago Abal

    Lightweight bug finders (also known as code scanners) are becoming popular, they scale well and can find simple yet common programming errors. It is now considered a good practice to integrate these tools as part of your development process. The Linux project, for instance, has an automated testing...... service, known as the Kbuild robot, that runs a few of these code scanners. In this project, I have carefully studied tens of historical Linux bugs, and I have found that many of these bugs, despite being conceptually simple, were not caught by any code scanning tool. The reason is that, by design, code...... scanners will find mostly superficial errors. Thus, when bugs span multiple functions, even if simple, they become undetectable by most code scanners. The studied set of historical bugs contained many of such cases. This PhD thesis proposes a bug-finding technique that is both lightweight and capable...

  15. Harvesting Venom Toxins from Assassin Bugs and Other Heteropteran Insects.

    Science.gov (United States)

    Walker, Andrew Allan; Rosenthal, Max; Undheim, Eivind E A; King, Glenn F

    2018-04-21

    Heteropteran insects such as assassin bugs (Reduviidae) and giant water bugs (Belostomatidae) descended from a common predaceous and venomous ancestor, and the majority of extant heteropterans retain this trophic strategy. Some heteropterans have transitioned to feeding on vertebrate blood (such as the kissing bugs, Triatominae; and bed bugs, Cimicidae) while others have reverted to feeding on plants (most Pentatomomorpha). However, with the exception of saliva used by kissing bugs to facilitate blood-feeding, little is known about heteropteran venoms compared to the venoms of spiders, scorpions and snakes. One obstacle to the characterization of heteropteran venom toxins is the structure and function of the venom/labial glands, which are both morphologically complex and perform multiple biological roles (defense, prey capture, and extra-oral digestion). In this article, we describe three methods we have successfully used to collect heteropteran venoms. First, we present electrostimulation as a convenient way to collect venom that is often lethal when injected into prey animals, and which obviates contamination by glandular tissue. Second, we show that gentle harassment of animals is sufficient to produce venom extrusion from the proboscis and/or venom spitting in some groups of heteropterans. Third, we describe methods to harvest venom toxins by dissection of anaesthetized animals to obtain the venom glands. This method is complementary to other methods, as it may allow harvesting of toxins from taxa in which electrostimulation and harassment are ineffective. These protocols will enable researchers to harvest toxins from heteropteran insects for structure-function characterization and possible applications in medicine and agriculture.

  16. R2WinBUGS: A Package for Running WinBUGS from R

    Directory of Open Access Journals (Sweden)

    Sibylle Sturtz

    2005-01-01

    Full Text Available The R2WinBUGS package provides convenient functions to call WinBUGS from R. It automatically writes the data and scripts in a format readable by WinBUGS for processing in batch mode, which is possible since version 1.4. After the WinBUGS process has finished, it is possible either to read the resulting data into R by the package itself--which gives a compact graphical summary of inference and convergence diagnostics--or to use the facilities of the coda package for further analyses of the output. Examples are given to demonstrate the usage of this package.

  17. Modified bug-1 algorithm based strategy for obstacle avoidance in multi robot system

    Directory of Open Access Journals (Sweden)

    Kandathil Jom J.

    2018-01-01

    Full Text Available One of the primary ability of an intelligent mobile robot system is obstacle avoidance. BUG algorithms are classic examples of the algorithms used for achieving obstacle avoidance. Unlike many other planning algorithms based on global knowledge, BUG algorithms assume only local knowledge of the environment and a global goal. Among the variations of the BUG algorithms that prevail, BUG-0, BUG-1 and BUG-2 are the more prominent versions. The exhaustive search algorithm present in BUG-1 makes it more reliable and safer for practical applications. Overall, this provides a more predictable and dependable performance. Hence, the essential focus in this paper is on implementing the BUG-1 algorithm across a group of robots to move them from a start location to a target location. The results are compared with the results from BUG-1 algorithm implemented on a single robot. The strategy developed in this work reduces the time involved in moving the robots from starting location to the target location. Further, the paper shows that the total distance covered by each robot in a multi robot-system is always lesser than or equal to that travelled by a single robot executing the same problem.

  18. Two-dimensional lift-up problem for a rigid porous bed

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Y.; Huang, L. H.; Yang, F. P. Y. [Department of Civil Engineering, National Taiwan University, Taipei, Taiwan (China)

    2015-05-15

    The present study analytically reinvestigates the two-dimensional lift-up problem for a rigid porous bed that was studied by Mei, Yeung, and Liu [“Lifting of a large object from a porous seabed,” J. Fluid Mech. 152, 203 (1985)]. Mei, Yeung, and Liu proposed a model that treats the bed as a rigid porous medium and performed relevant experiments. In their model, they assumed the gap flow comes from the periphery of the gap, and there is a shear layer in the porous medium; the flow in the gap is described by adhesion approximation [D. J. Acheson, Elementary Fluid Dynamics (Clarendon, Oxford, 1990), pp. 243-245.] and the pore flow by Darcy’s law, and the slip-flow condition proposed by Beavers and Joseph [“Boundary conditions at a naturally permeable wall,” J. Fluid Mech. 30, 197 (1967)] is applied to the bed interface. In this problem, however, the gap flow initially mainly comes from the porous bed, and the shear layer may not exist. Although later the shear effect becomes important, the empirical slip-flow condition might not physically respond to the shear effect, and the existence of the vertical velocity affects the situation so greatly that the slip-flow condition might not be appropriate. In contrast, the present study proposes a more general model for the problem, applying Stokes flow to the gap, the Brinkman equation to the porous medium, and Song and Huang’s [“Laminar poroelastic media flow,” J. Eng. Mech. 126, 358 (2000)] complete interfacial conditions to the bed interface. The exact solution to the problem is found and fits Mei’s experiments well. The breakout phenomenon is examined for different soil beds, mechanics that cannot be illustrated by Mei’s model are revealed, and the theoretical breakout times obtained using Mei’s model and our model are compared. The results show that the proposed model is more compatible with physics and provides results that are more precise.

  19. Developing e-Bug web games to teach microbiology.

    Science.gov (United States)

    Farrell, David; Kostkova, Patty; Lazareck, Lisa; Weerasinghe, Dasun; Weinberg, Julius; Lecky, Donna M; Adriaenssens, Niels; Koprivová Herotová, Tereza; Holt, Jette; Touboul, Pia; Merakou, Kyriakoula; Koncan, Raffaella; Olczak-Pienkowska, Anna; Avô, António Brito; Campos, José; McNulty, Cliodna A M

    2011-06-01

    As a complement to the e-Bug teaching pack, two e-Bug games were developed to provide content that aimed to entertain as well as to educate. A set of agreed learning outcomes (LOs) were provided by the scientific partners of the e-Bug Project and the games were developed using user-centred design techniques (the needs, wants and limitations of the potential game players were assessed at each stage of the design process). The e-Bug games were designed for two age groups: Junior (9-12 year olds); and Senior (13-15 year olds). A study using focus groups was done to gain an understanding as to the types of games enjoyed by the target users. According to the preliminary study, the Junior Game was developed as a platform game and the Senior Game was developed as a story-based detective game. The Junior Game consists of five levels, each associated with a set of LOs. Similarly, the Senior Game consists of four missions, each comprising five stages using problem-based learning techniques and LOs. In this paper, the process of development for each game is described in detail and an illustration is provided of how each game level or mission addresses the target LOs. Development of the games used feedback acquired from children in four schools across the UK (Glasgow, London and two in Gloucester). The children were selected according to their willingness to participate. European Partners of the e-Bug Project also provided further support, translation and requests for modifications. The knowledge gained of LOs and further evaluation of the games is continuing, and preliminary results are in press. The final versions of the games, translated into 11 European languages, are available online via www.e-bug.eu.

  20. Using Software Dependency to Bug Prediction

    Directory of Open Access Journals (Sweden)

    Peng He

    2013-01-01

    Full Text Available Software maintenance, especially bug prediction, plays an important role in evaluating software quality and balancing development costs. This study attempts to use several quantitative network metrics to explore their relationships with bug prediction in terms of software dependency. Our work consists of four main steps. First, we constructed software dependency networks regarding five dependency scenes at the class-level granularity. Second, we used a set of nine representative and commonly used metrics—namely, centrality, degree, PageRank, and HITS, as well as modularity—to quantify the importance of each class. Third, we identified how these metrics were related to the proneness and severity of fixed bugs in Tomcat and Ant and determined the extent to which they were related. Finally, the significant metrics were considered as predictors for bug proneness and severity. The result suggests that there is a statistically significant relationship between class’s importance and bug prediction. Furthermore, betweenness centrality and out-degree metric yield an impressive accuracy for bug prediction and test prioritization. The best accuracy of our prediction for bug proneness and bug severity is up to 54.7% and 66.7% (top 50, Tomcat and 63.8% and 48.7% (top 100, Ant, respectively, within these two cases.

  1. Bayesian modeling using WinBUGS

    CERN Document Server

    Ntzoufras, Ioannis

    2009-01-01

    A hands-on introduction to the principles of Bayesian modeling using WinBUGS Bayesian Modeling Using WinBUGS provides an easily accessible introduction to the use of WinBUGS programming techniques in a variety of Bayesian modeling settings. The author provides an accessible treatment of the topic, offering readers a smooth introduction to the principles of Bayesian modeling with detailed guidance on the practical implementation of key principles. The book begins with a basic introduction to Bayesian inference and the WinBUGS software and goes on to cover key topics, including: Markov Chain Monte Carlo algorithms in Bayesian inference Generalized linear models Bayesian hierarchical models Predictive distribution and model checking Bayesian model and variable evaluation Computational notes and screen captures illustrate the use of both WinBUGS as well as R software to apply the discussed techniques. Exercises at the end of each chapter allow readers to test their understanding of the presented concepts and all ...

  2. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... and treatments Acne and rosacea Bumps and growths Color problems Contagious skin diseases Cosmetic treatments Dry / sweaty ... prevent bug bites, dermatologists recommend the following tips: Use insect repellent. To protect against mosquitoes, ticks and ...

  3. 42 Variability Bugs in the Linux Kernel

    DEFF Research Database (Denmark)

    Abal, Iago; Brabrand, Claus; Wasowski, Andrzej

    2014-01-01

    Feature-sensitive verification pursues effective analysis of the exponentially many variants of a program family. However, researchers lack examples of concrete bugs induced by variability, occurring in real large-scale systems. Such a collection of bugs is a requirement for goal-oriented research...... provide self-contained simplified C99 versions of the bugs, facilitating understanding and tool evaluation. Our study provides insights into the nature and occurrence of variability bugs in a large C software system, and shows in what ways variability affects and increases the complexity of software bugs....

  4. Analysis of 44 Cases before the Landlord and Tenant Board Involving Bed Bug Infestations in Ontario, Canada: Focus on Adjudicator Decisions Based on Entomological/Pest Management Evidence and Accountability under the Residential Tenancy Act and Other Applicable Legislation.

    Science.gov (United States)

    Bryks, Sam

    2011-07-19

    The resurgence of bed bugs in major urban centres in North America has resulted in conflict between landlords and tenants. This is commonly focused on attribution of blame for source of infestation, on responsibility, on costs for preparation, treatment and losses, and for compensation as rent abatement and/or alternative temporary housing. In Ontario, Canada, these issues are often decided by adjudicators at the Landlord and Tenant Board hearing claims, counter-claims and defense by legal representation (lawyers and paralegals) as well as through mediation. Evidence in these hearings may include photographs, invoices for costs as well as testimony by tenants, landlords and "expert witnesses" who are most often pest control firms representing their landlord clients. A total of 44 Landlord and Tenant Board adjudicated cases available online were analyzed. The analysis included elements of the decisions such as adjudicator, claimant (landlord or tenant), basis of claim, review of evidence, amount of claim, amount awarded, and evaluation of the quality of the evidence. The results of the analysis of these findings are discussed. Recommendations for improvement of adjudicator decisions on the basis of knowledge of bed bug biology and Integrated Pest Management best practices are presented as well as the importance of education of tenants and landlords to a process of mutual trust, support and accountability.

  5. Analysis of 44 Cases before the Landlord and Tenant Board Involving Bed Bug Infestations in Ontario, Canada: Focus on Adjudicator Decisions Based on Entomological/Pest Management Evidence and Accountability under the Residential Tenancy Act and Other Applicable Legislation

    Science.gov (United States)

    Bryks, Sam

    2011-01-01

    The resurgence of bed bugs in major urban centres in North America has resulted in conflict between landlords and tenants. This is commonly focused on attribution of blame for source of infestation, on responsibility, on costs for preparation, treatment and losses, and for compensation as rent abatement and/or alternative temporary housing. In Ontario, Canada, these issues are often decided by adjudicators at the Landlord and Tenant Board hearing claims, counter-claims and defense by legal representation (lawyers and paralegals) as well as through mediation. Evidence in these hearings may include photographs, invoices for costs as well as testimony by tenants, landlords and “expert witnesses” who are most often pest control firms representing their landlord clients. A total of 44 Landlord and Tenant Board adjudicated cases available online were analyzed. The analysis included elements of the decisions such as adjudicator, claimant (landlord or tenant), basis of claim, review of evidence, amount of claim, amount awarded, and evaluation of the quality of the evidence. The results of the analysis of these findings are discussed. Recommendations for improvement of adjudicator decisions on the basis of knowledge of bed bug biology and Integrated Pest Management best practices are presented as well as the importance of education of tenants and landlords to a process of mutual trust, support and accountability. PMID:26467732

  6. Monitoring stink bugs (Hemiptera: Pentatomidae) in mid-Atlantic apple and peach orchards.

    Science.gov (United States)

    Leskey, T C; Hogmire, H W

    2005-02-01

    Pyramid traps coated with "industrial safety yellow" exterior latex gloss enamel paint and baited with Euschistus spp. aggregation pheromone, methyl (2E,4Z)-decadienoate captured more stink bugs than all other baited and unbaited trap types in both apple and peach orchards in 2002 and 2003. Commercial sources of dispensers of methyl (2E,4Z)-decadienoate deployed in association with pyramid traps had a significant impact on trap captures. Captures in pyramid traps were four-fold greater when baited with lures from IPM Technologies, Inc. (Portland, OR) than with lures from Suterra (Bend, OR). Variation in yellow pyramid trap color ("industrial safety yellow" and "standard coroplast yellow") and material (plywood, plastic, and masonite) did not affect trap captures. Brown stink bug was the predominant species captured (58%), followed by dusky stink bug, Euschistus tristigmus (Say) (20%); green stink bug, Acrosternum hilare (Say) (14%); and other stink bugs (Brochymena spp. and unidentified nymphs) (8%). Captures in baited pyramid traps were significantly correlated with tree beating samples in both managed and unmanaged apple orchards and with sweep netting samples in the unmanaged apple orchard. However, problems associated with trapping mechanisms of pyramid trap jar tops and jar traps likely resulted in reduced captures in baited traps. Improved trapping mechanisms must be established to develop an effective monitoring tool for stink bugs in mid-Atlantic orchards.

  7. Bug City: Beetles [Videotape].

    Science.gov (United States)

    1998

    "Bug City" is a video series created to help children learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic photography,…

  8. Bug City: Bees [Videotape].

    Science.gov (United States)

    1998

    "Bug City" is a video series created to help children learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic photography,…

  9. Bug City: Ants [Videotape].

    Science.gov (United States)

    1998

    "Bug City" is a video series created to help children (grades 1-6) learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic…

  10. 40 Variability Bugs in the Linux Kernel

    DEFF Research Database (Denmark)

    Abal Rivas, Iago; Brabrand, Claus; Wasowski, Andrzej

    2014-01-01

    Feature-sensitive verification is a recent field that pursues the effective analysis of the exponential number of variants of a program family. Today researchers lack examples of concrete bugs induced by variability, and occurring in real large-scale software. Such a collection of bugs is a requi......Feature-sensitive verification is a recent field that pursues the effective analysis of the exponential number of variants of a program family. Today researchers lack examples of concrete bugs induced by variability, and occurring in real large-scale software. Such a collection of bugs...... the outcome of our analysis into a database. In addition, we provide self-contained simplified C99 versions of the bugs, facilitating understanding and tool evaluation. Our study provides insights about the nature and occurrence of variability bugs in a large C software system, and shows in what ways...

  11. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... Tips to prevent and treat bug bites Although most bug bites are harmless, some can spread dangerous ... one’s greatest efforts, bug bites still happen. Fortunately, most bug bites and stings can be safely treated ...

  12. RNA-Seq and molecular docking reveal multi-level pesticide resistance in the bed bug

    Directory of Open Access Journals (Sweden)

    Mamidala Praveen

    2012-01-01

    Full Text Available Abstract Background Bed bugs (Cimex lectularius are hematophagous nocturnal parasites of humans that have attained high impact status due to their worldwide resurgence. The sudden and rampant resurgence of C. lectularius has been attributed to numerous factors including frequent international travel, narrower pest management practices, and insecticide resistance. Results We performed a next-generation RNA sequencing (RNA-Seq experiment to find differentially expressed genes between pesticide-resistant (PR and pesticide-susceptible (PS strains of C. lectularius. A reference transcriptome database of 51,492 expressed sequence tags (ESTs was created by combining the databases derived from de novo assembled mRNA-Seq tags (30,404 ESTs and our previous 454 pyrosequenced database (21,088 ESTs. The two-way GLMseq analysis revealed ~15,000 highly significant differentially expressed ESTs between the PR and PS strains. Among the top 5,000 differentially expressed ESTs, 109 putative defense genes (cuticular proteins, cytochrome P450s, antioxidant genes, ABC transporters, glutathione S-transferases, carboxylesterases and acetyl cholinesterase involved in penetration resistance and metabolic resistance were identified. Tissue and development-specific expression of P450 CYP3 clan members showed high mRNA levels in the cuticle, Malpighian tubules, and midgut; and in early instar nymphs, respectively. Lastly, molecular modeling and docking of a candidate cytochrome P450 (CYP397A1V2 revealed the flexibility of the deduced protein to metabolize a broad range of insecticide substrates including DDT, deltamethrin, permethrin, and imidacloprid. Conclusions We developed significant molecular resources for C. lectularius putatively involved in metabolic resistance as well as those participating in other modes of insecticide resistance. RNA-Seq profiles of PR strains combined with tissue-specific profiles and molecular docking revealed multi-level insecticide

  13. Bug City: Aquatic Insects [Videotape].

    Science.gov (United States)

    1998

    "Bug City" is a video series created to help children learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic photography,…

  14. Bug City: Flies & Mosquitoes [Videotape].

    Science.gov (United States)

    1998

    "Bug City" is a video series created to help children (grades 1-6) learn about insects and other small critters. All aspects of bug life are touched upon, including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic…

  15. Bug City: Ladybugs & Fireflies [Videotape].

    Science.gov (United States)

    1998

    "Bug City" is a video series created to help children (grades 1-6) learn about insects and other small critters. All aspects of bug life are touched upon, including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic…

  16. Towards Easing the Diagnosis of Bugs in OS Code

    DEFF Research Database (Denmark)

    Stuart, Henrik; Hansen, René Rydhof; Lawall, Julia Laetitia

    2007-01-01

    The rapid detection and treatment of bugs in operating systems code is essential to maintain the overall security and dependability of a computing system.  A number of techniques have been proposed for detecting bugs, but little has been done to help developers analyze and treat them.  In this pa......The rapid detection and treatment of bugs in operating systems code is essential to maintain the overall security and dependability of a computing system.  A number of techniques have been proposed for detecting bugs, but little has been done to help developers analyze and treat them.......  In this paper we propose to combine bug-finding rules with transformations that automatically introduce bug-fixes or workarounds when a possible bug is detected.  This work builds on our previous work on the Coccinelle tool, which targets device driver evolution....

  17. Variability Bugs in Highly Configurable Systems: A Qualitative Analysis

    DEFF Research Database (Denmark)

    Abal, Iago; Melo, Jean; Stanciulescu, Stefan

    2018-01-01

    Variability-sensitive verification pursues effective analysis of the exponentially many variants in number of features of a program family. Several variability-aware techniques have been proposed, but researchers still lack examples of concrete bugs induced by variability, occurring in real large......-scale systems. A collection of real world bugs is needed to evaluate tool implementations of variability-sensitive analyses by testing them on real bugs. We present a qualitative study of 98 diverse variability bugs collected from bug-fixing commits in the Apache, BusyBox, Linux kernel and Marlin repositories....... We analyze each of the bugs, and record the results in a database. For each bug, we create a self-contained simplified C99 version and a simplified patch, in order to help researchers who are not experts on these subject studies to understand them, so that they can use it for evaluation...

  18. Extensive fragmentation of the X chromosome in the bed bug Cimex lectularius Linnaeus, 1758 (Heteroptera, Cimicidae: a survey across Europe

    Directory of Open Access Journals (Sweden)

    David Sadílek

    2013-10-01

    Full Text Available Variation in the number of chromosomes was revealed in 61 samples of Cimex lectularius Linnaeus, 1758 from the Czech Republic and other European countries, hosted on Myotis Kaup, 1829 (4 and Homo sapiens Linnaeus, 1758 (57. The karyotype of all the specimens of C. lectularius analysed contained 26 autosomes and a varying number of the sex chromosomes. The number of sex chromosomes showed extensive variation, and up to 20 fragments were recorded. Altogether, 12 distinct karyotypes were distinguished. The male karyotypes consisted of 29, 30, 31, 32, 33, 34, 35, 36, 37, 40, 42 and 47 chromosomes. The females usually exhibited the number of chromosomes which was complementary to the number established in the males from the same sample. However, 11 polymorphic samples were revealed in which the karyotypes of females and males were not complementary each other. The complement with 2n = 26+X1X2Y was found in 44% of the specimens and 57,4% samples of bed bugs studied. The karyotypes with higher chromosome numbers as well as individuals with chromosomal mosaics were usually found within the samples exhibiting particularly extensive variation between individuals, and such complements were not found within samples contaning a few or single specimen. The occurrence of chromosomal mosaics with the karyotype constitution varying between cells of single individual was observed in five specimens (4.3% from five samples. We assume that polymorphism caused by fragmentation of the X chromosome may result in meiotic problems and non-disjunction can produce unbalanced gametes and result in lowered fitness of individuals carrying higher numbers of the X chromosome fragments. This effect should be apparently enhanced with the increasing number of the fragments and this may be the reason for the observed distribution pattern of individual karyotypes in the studied samples and the rarity of individuals with extremely high chromosome numbers. The assumed lowering of the

  19. Genetic Diversity and Phylogenetic Relationships of Cytochrome C Oxidase Subunit I in Cimex hemipterus (Hemiptera: Cimicidae) Populations in Malaysia.

    Science.gov (United States)

    Seri Masran, Siti Nor Ain; Ab Majid, Abdul Hafiz

    2017-07-01

    The tropical bed bug is scientifically recognized as a significant public health problem. While there is an increased awareness about their resurgence by medical and life science committees, efficient bed bug management still remains unresolved. The solution may soon arise, as information about bed bugs' infestation dynamics and systematics are becoming more distinguishable. Recent developments in studies about bed bugs are based on molecular intervention by determining their genetic variation and phylogeography. The aim of this study is to assess the phylogenetic relationships and genetic diversity among the populations of tropical bed bugs inhabiting Malaysia. A molecular genotyping study was conducted with 22 tropical bed bug populations composed of three individuals per population. The mitochondrial (COI) gene was used as a marker. The data obtained were analyzed using the T-Coffee, ClustalX, MEGA 6.0, and PAUP software. The results showed one main monophyletic clade that consisted of two groups: Ch01 and Ch02. Ch02 consists of samples from the Bandar Hilir population, differing from the other populations studied by one singleton base. However, as there were no changes in the amino acid, this singleton genetic variation was considered to have no effect on genetic differentiation. Ch01 shows similarity with some sequence of Cimex hemipterus (F.) from Thailand, suggesting an international diversity connection. The disparity index apparently suggests that all isolates are homogeneous populations and are supported by the low value of the mean pairwise distance between isolates. This study will increase the knowledge about phylogeographic diversity of tropical bed bug in Malaysia. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Assassin bug uses aggressive mimicry to lure spider prey.

    Science.gov (United States)

    Wignall, Anne E; Taylor, Phillip W

    2011-05-07

    Assassin bugs (Stenolemus bituberus) hunt web-building spiders by invading the web and plucking the silk to generate vibrations that lure the resident spider into striking range. To test whether vibrations generated by bugs aggressively mimic the vibrations generated by insect prey, we compared the responses of spiders to bugs with how they responded to prey, courting male spiders and leaves falling into the web. We also analysed the associated vibrations. Similar spider orientation and approach behaviours were observed in response to vibrations from bugs and prey, whereas different behaviours were observed in response to vibrations from male spiders and leaves. Peak frequency and duration of vibrations generated by bugs were similar to those generated by prey and courting males. Further, vibrations from bugs had a temporal structure and amplitude that were similar to vibrations generated by leg and body movements of prey and distinctly different to vibrations from courting males or leaves, or prey beating their wings. To be an effective predator, bugs do not need to mimic the full range of prey vibrations. Instead bugs are general mimics of a subset of prey vibrations that fall within the range of vibrations classified by spiders as 'prey'.

  1. Stink Bug Feeding Induces Fluorescence in Developing Cotton Bolls

    Directory of Open Access Journals (Sweden)

    Toews Michael D

    2011-08-01

    Full Text Available Abstract Background Stink bugs (Hemiptera: Pentatomidae comprise a critically important insect pest complex affecting 12 major crops worldwide including cotton. In the US, stink bug damage to developing cotton bolls causes boll abscission, lint staining, reduced fiber quality, and reduced yields with estimated losses ranging from 10 to 60 million dollars annually. Unfortunately, scouting for stink bug damage in the field is laborious and excessively time consuming. To improve scouting accuracy and efficiency, we investigated fluorescence changes in cotton boll tissues as a result of stink bug feeding. Results Fluorescent imaging under long-wave ultraviolet light showed that stink bug-damaged lint, the inner carpal wall, and the outside of the boll emitted strong blue-green fluorescence in a circular region near the puncture wound, whereas undamaged tissue emissions occurred at different wavelengths; the much weaker emission of undamaged tissue was dominated by chlorophyll fluorescence. We further characterized the optimum emission and excitation spectra to distinguish between stink bug damaged bolls from undamaged bolls. Conclusions The observed characteristic fluorescence peaks associated with stink bug damage give rise to a fluorescence-based method to rapidly distinguish between undamaged and stink bug damaged cotton bolls. Based on the fluorescent fingerprint, we envision a fluorescence reflectance imaging or a fluorescence ratiometric device to assist pest management professionals with rapidly determining the extent of stink bug damage in a cotton field.

  2. Kissing Bug ( spp. Intrusion into Homes: Troublesome Bites and Domiciliation

    Directory of Open Access Journals (Sweden)

    Stephen A. Klotz

    2016-01-01

    Full Text Available Kissing bugs ( Triatoma spp. frequently enter homes and bite human and pet occupants. Bites may lead to severe allergic reactions and, in some cases, death. Kissing bugs are also vectors of Trypanosoma cruzi , the cause of Chagas disease. In general, modern houses in the United States are not conducive to domiciliation of kissing bugs (bugs living out their entire life within the home with the presence of eggs, nymphs, adults, and exuviae. Construction features such as concrete foundations, solid walls and ceilings, window screens, tight thresholds for doors and windows, and other measures impede bug entry into homes, and air conditioning reduces the need for open doors and windows. Where Chagas disease is endemic in Mexico and Central and South America, homes often have thatch roofs, adobe walls, and open doors and windows. We investigated numerous instances of kissing bug intrusions into homes in Southern Arizona, California, and Louisiana and documented the reactions to kissing bug bites. Our work confirms the importance of modern home construction in limiting kissing bug intrusions. Older homes, especially those lacking modern screening, caulking, and weather stripping to reduce air leakage, may be subject to kissing bug intrusions and domiciliation. We describe a community in Southern Arizona where domiciliation of homes by Triatoma recurva is common. We also provide recent data regarding kissing bug bites and allergic reactions to the bites.

  3. Bug City: Crickets, Grasshoppers & Friends [Videotape].

    Science.gov (United States)

    1998

    "Bug City" is a video series created to help children (grades 1-6) learn about insects and other small critters. All aspects of bug life are touched upon, including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic…

  4. Bug City: Spiders and Scorpions [Videotape].

    Science.gov (United States)

    1998

    "Bug City" is a video series created to help children learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic photography,…

  5. Bug City: Butterflies and Moths [Videotape].

    Science.gov (United States)

    1998

    "Bug City" is a video series created to help children learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic photography,…

  6. Machine Learning or Information Retrieval Techniques for Bug Triaging: Which is better?

    Directory of Open Access Journals (Sweden)

    Anjali Goyal

    2017-07-01

    Full Text Available Bugs are the inevitable part of a software system. Nowadays, large software development projects even release beta versions of their products to gather bug reports from users. The collected bug reports are then worked upon by various developers in order to resolve the defects and make the final software product more reliable. The high frequency of incoming bugs makes the bug handling a difficult and time consuming task. Bug assignment is an integral part of bug triaging that aims at the process of assigning a suitable developer for the reported bug who corrects the source code in order to resolve the bug. There are various semi and fully automated techniques to ease the task of bug assignment. This paper presents the current state of the art of various techniques used for bug report assignment. Through exhaustive research, the authors have observed that machine learning and information retrieval based bug assignment approaches are most popular in literature. A deeper investigation has shown that the trend of techniques is taking a shift from machine learning based approaches towards information retrieval based approaches. Therefore, the focus of this work is to find the reason behind the observed drift and thus a comparative analysis is conducted on the bug reports of the Mozilla, Eclipse, Gnome and Open Office projects in the Bugzilla repository. The results of the study show that the information retrieval based technique yields better efficiency in recommending the developers for bug reports.

  7. NRFixer: Sentiment Based Model for Predicting the Fixability of Non-Reproducible Bugs

    Directory of Open Access Journals (Sweden)

    Anjali Goyal

    2017-08-01

    Full Text Available Software maintenance is an essential step in software development life cycle. Nowadays, software companies spend approximately 45\\% of total cost in maintenance activities. Large software projects maintain bug repositories to collect, organize and resolve bug reports. Sometimes it is difficult to reproduce the reported bug with the information present in a bug report and thus this bug is marked with resolution non-reproducible (NR. When NR bugs are reconsidered, a few of them might get fixed (NR-to-fix leaving the others with the same resolution (NR. To analyse the behaviour of developers towards NR-to-fix and NR bugs, the sentiment analysis of NR bug report textual contents has been conducted. The sentiment analysis of bug reports shows that NR bugs' sentiments incline towards more negativity than reproducible bugs. Also, there is a noticeable opinion drift found in the sentiments of NR-to-fix bug reports. Observations driven from this analysis were an inspiration to develop a model that can judge the fixability of NR bugs. Thus a framework, {NRFixer,} which predicts the probability of NR bug fixation, is proposed. {NRFixer} was evaluated with two dimensions. The first dimension considers meta-fields of bug reports (model-1 and the other dimension additionally incorporates the sentiments (model-2 of developers for prediction. Both models were compared using various machine learning classifiers (Zero-R, naive Bayes, J48, random tree and random forest. The bug reports of Firefox and Eclipse projects were used to test {NRFixer}. In Firefox and Eclipse projects, J48 and Naive Bayes classifiers achieve the best prediction accuracy, respectively. It was observed that the inclusion of sentiments in the prediction model shows a rise in the prediction accuracy ranging from 2 to 5\\% for various classifiers.

  8. Kissing Bug (Triatoma spp.) Intrusion into Homes: Troublesome Bites and Domiciliation.

    Science.gov (United States)

    Klotz, Stephen A; Shirazi, F Mazda; Boesen, Keith; Beatty, Norman L; Dorn, Patricia L; Smith, Shannon; Schmidt, Justin O

    2016-01-01

    Kissing bugs (Triatoma spp.) frequently enter homes and bite human and pet occupants. Bites may lead to severe allergic reactions and, in some cases, death. Kissing bugs are also vectors of Trypanosoma cruzi, the cause of Chagas disease. In general, modern houses in the United States are not conducive to domiciliation of kissing bugs (bugs living out their entire life within the home with the presence of eggs, nymphs, adults, and exuviae). Construction features such as concrete foundations, solid walls and ceilings, window screens, tight thresholds for doors and windows, and other measures impede bug entry into homes, and air conditioning reduces the need for open doors and windows. Where Chagas disease is endemic in Mexico and Central and South America, homes often have thatch roofs, adobe walls, and open doors and windows. We investigated numerous instances of kissing bug intrusions into homes in Southern Arizona, California, and Louisiana and documented the reactions to kissing bug bites. Our work confirms the importance of modern home construction in limiting kissing bug intrusions. Older homes, especially those lacking modern screening, caulking, and weather stripping to reduce air leakage, may be subject to kissing bug intrusions and domiciliation. We describe a community in Southern Arizona where domiciliation of homes by Triatoma recurva is common. We also provide recent data regarding kissing bug bites and allergic reactions to the bites.

  9. Early perception of stink bug damage in developing seeds of field-grown soybean induces chemical defences and reduces bug attack.

    Science.gov (United States)

    Giacometti, Romina; Barneto, Jesica; Barriga, Lucia G; Sardoy, Pedro M; Balestrasse, Karina; Andrade, Andrea M; Pagano, Eduardo A; Alemano, Sergio G; Zavala, Jorge A

    2016-08-01

    Southern green stink bugs (Nezara viridula L.) invade field-grown soybean crops, where they feed on developing seeds and inject phytotoxic saliva, which causes yield reduction. Although leaf responses to herbivory are well studied, no information is available about the regulation of defences in seeds. This study demonstrated that mitogen-activated protein kinases MPK3, MPK4 and MPK6 are expressed and activated in developing seeds of field-grown soybean and regulate a defensive response after stink bug damage. Although 10-20 min after stink bug feeding on seeds induced the expression of MPK3, MPK6 and MPK4, only MPK6 was phosphorylated after damage. Herbivory induced an early peak of jasmonic acid (JA) accumulation and ethylene (ET) emission after 3 h in developing seeds, whereas salicylic acid (SA) was also induced early, and at increasing levels up to 72 h after damage. Damaged seeds upregulated defensive genes typically modulated by JA/ET or SA, which in turn reduced the activity of digestive enzymes in the gut of stink bugs. Induced seeds were less preferred by stink bugs. This study shows that stink bug damage induces seed defences, which is perceived early by MPKs that may activate defence metabolic pathways in developing seeds of field-grown soybean. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  10. Finding error handling bugs in OpenSSL using Coccinelle

    DEFF Research Database (Denmark)

    Lawall, Julia; Laurie, Ben; Hansen, René Rydhof

    2010-01-01

    OpenSSL is a library providing various functionalities relating to secure network communication.  Detecting and fixing bugs in OpenSSL code is thus essential, particularly when such bugs can lead to malicious attacks.  In previous work, we have proposed a methodology for finding API usage protocols...... in Linux kernel code using the program matching and transformation engine Coccinelle.  In this work, we report on our experience in applying this methodology to OpenSSL, focusing on API usage protocols related to error handling.  We have detected over 30 bugs in a recent OpenSSL snapshot, and in many cases...... it was possible to correct the bugs automatically.  Our patches correcting these bugs have been accepted by the OpenSSL developers.  This work furthermore confirms the applicability of our methodology to user-level code....

  11. Bug City: House and Backyard Insects [Videotape].

    Science.gov (United States)

    1998

    "Bug City" is a video series created to help children learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic photography,…

  12. Comparison of management strategies for squash bugs (Hemiptera: Coreidae) in watermelon.

    Science.gov (United States)

    Dogramaci, Mahmut; Shrefler, James W; Roberts, B Warren; Pair, Sam; Edelson, J V

    2004-12-01

    Two watermelon pest management practices, a squash trap crop and a standard recommendation using soil-applied carbofuran, were compared using large-scale field plots to assess trap crop suitability as a replacement for the standard in 2000, 2001, and 2002. In both systems, foliar insecticide applications were used to control squash bugs when populations exceeded threshold levels. During 2001 and 2002, a treatment of untreated watermelon was used. Early season adult insects, from seedling to fruit set, are most critical for watermelon. Significantly fewer early adult bugs were found on watermelon in the trap crop than in the standard recommended practice in 1 of 3 yr. In both years, significantly fewer adult squash bugs were found in watermelon in the trap crop than in untreated fields. The standard recommended practice significantly reduced adult squash bugs in watermelon compared with the untreated in 1 of 2 yr. There was no significant correlation of watermelon yield and squash bug density, indicating that squash bug densities were too low to impact yield. Although squash bugs were reduced significantly by the trap crop, marketable watermelon yields were lower in the squash trap crop than in untreated watermelon, suggesting that pest management treatments may interfere with crop productivity factors other than squash bug colonization. Results suggest that mid-season production squash bug should be managed by monitoring populations and using insecticides as needed rather than using at-plant treatment. Further research is needed to compare treatments during early-season production.

  13. Effective Bug Finding in C Programs with Shape and Effect Abstractions

    DEFF Research Database (Denmark)

    Abal, Iago; Brabrand, Claus; Wasowski, Andrzej

    2017-01-01

    Software projects tend to suffer from conceptually simple resource manipulation bugs, such as accessing a de-allocated memory region, or acquiring a non-reentrant lock twice. Static code scanners are used extensively to remove these bugs from projects like the Linux kernel. Yet, when the manipula......Software projects tend to suffer from conceptually simple resource manipulation bugs, such as accessing a de-allocated memory region, or acquiring a non-reentrant lock twice. Static code scanners are used extensively to remove these bugs from projects like the Linux kernel. Yet, when...... the Linux kernel. Our results show that our tool is more effective at finding bugs than similar code-scanning tools. EBA analyzes the drivers/ directory of Linux (nine thousand files) in less than thirty minutes, and uncovers a handful previously unknown double-lock bugs in various drivers....

  14. Between-group transmission dynamics of the swallow bug, Oeciacus vicarius.

    Science.gov (United States)

    Brown, Charles R; Brown, Mary Bomberger

    2005-06-01

    The parasitic cimicid swallow bug, Oeciacus vicarius, is the principal invertebrate vector for Buggy Creek virus (BCRV) and has also been associated with Venezuelan equine encephalitis virus. To help understand the spread of this vector, we experimentally measured the transmission of O. vicarius between groups (colonies) of its main host, the cliff swallow (Petrochelidonpyrrhonota), in the field. Transmission of bugs between colonies varied significantly with year, size of the colony, and week within the season. Bug immigration into sites tended to peak in mid-summer. Swallow nests in larger colonies had more consistent rates of bug introduction than did nests in small colonies, but within a colony a given nest's weekly immigrant-bug count varied widely across the season. Transmission of O. vicarius between host social groups follows broadly predictable seasonal patterns, but there is nevertheless temporal and spatial heterogeneity in bug transmission. By understanding how long-distance movement by this vector varies in time and space, we can better predict where and when BCRV epizootics may occur.

  15. Implementation of the e-Bug Project in Greece.

    Science.gov (United States)

    Gennimata, Dimitra; Merakou, Kyriakoula; Barbouni, Anastasia; Kremastinou, Jenny

    2011-06-01

    The e-Bug pack and web site educational material has been translated and adapted to the Greek language and educational background, and implemented throughout Greece as a supplementary educational resource in elementary and junior high schools. Elementary and junior high school teachers in Greece have actively participated in the development of the e-Bug educational resource and supported the implementation of all e-Bug activities. Dissemination to all key national stakeholders has been undertaken, and endorsement has been obtained from educational and medical associations, societies and institutions. Independent evaluation has been carried out, as part of dissertation thesis projects, for postgraduate studies. The e-Bug educational resource provides all the essentials for the dissemination of good health behaviours in hygiene, monitoring the spread of infection and the prudent use of antibiotics, to the youth of this country. Its contribution is expected to be evident in the next adult generation.

  16. Formal solution for the fields within a beam-bug calibrator

    International Nuclear Information System (INIS)

    Fessenden, T J.

    1998-01-01

    For some time I was bothered by the fact that measurements of offsets in the various bug calibration setups never agreed with the simple formulae (2) used for determining electron beam position in the Livermore induction linacs and transport systems. About 1983 I realized that the discrepancy arises from the way the bug calibrator simulates an electron beam in a conducting pipe. At that time I solved the problem using the method presented here. Unfortunately, I did not write it up at that time. After considerable effort, I was able to repeat the calculation. Since I have little confidence that after a few years I could ever do it again, I felt obliged to write it up in some detail. Our beam bug calibrator consists of two conducting cylinders, nominally concentric, that simulate the electron beam within a drift tube. The radii of the larger cylinder is 2.3 times that of the smaller giving an electrical impedance of 50 Ohms to the coaxial combination. To simulate a beam off-axis within a drift tube, the inner tube is moved relative to the outer tube. This only approximately simulates the motion of a beam because the surface current on the inner tube redistributes in response to the translation. Fortunately, the fields of the translated inner cylinder can be found exactly using complex variable theory (1)

  17. Learning from Mistakes --- A Comprehensive Study on Real World Concurrency Bug Characteristics

    International Nuclear Information System (INIS)

    Shan Lu; Soyeon Park; Eunsoo Seo; Yuanyuan Zhou

    2008-01-01

    The reality of multi-core hardware has made concurrent programs pervasive. Unfortunately, writing correct concurrent programs is difficult. Addressing this challenge requires advances in multiple directions, including concurrency bug detection, concurrent program testing, concurrent programming model design, etc. Designing effective techniques in all these directions will significantly benefit from a deep understanding of real world concurrency bug characteristics. This paper provides the first (to the best of our knowledge) comprehensive real world concurrency bug characteristic study. Specifically, we have carefully examined concurrency bug patterns, manifestation, and fix strategies of 105 randomly selected real world concurrency bugs from 4 representative server and client opensource applications (MySQL, Apache, Mozilla and OpenOffice). Our study reveals several interesting findings and provides useful guidance for concurrency bug detection, testing, and concurrent programming language design. Some of our findings are as follows: (1) Around one third of the examined non-deadlock concurrency bugs are caused by violation to programmers order intentions, which may not be easily expressed via synchronization primitives like locks and transactional memories; (2) Around 34% of the examined non-deadlock concurrency bugs involve multiple variables, which are not well addressed by existing bug detection tools; (3) About 92% of the examined concurrency bugs can be reliably triggered by enforcing certain orders among no more than 4 memory accesses. This indicates that testing concurrent programs can target at exploring possible orders among every small groups of memory accesses, instead of among all memory accesses; (4) About 73% of the examined non-deadlock concurrency bugs were not fixed by simply adding or changing locks, and many of the fixes were not correct at the first try, indicating the difficulty of reasoning concurrent execution by programmers.

  18. BUGS at work : a bicycle user group guide

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This guide provides practical advice to cyclists on how start a Bicycle User Group (BUG) at their workplace. It offers tools to encourage employers to be proactive in improving facilities in support of cycle commuting. Several BUGs across Canada have worked towards getting better bicycle parking, lockers and shower facilities at their workplace. Other incentives include policies such as flexible work hours for cyclist commuters; casual dress on Friday; reimbursement for the subsidized cost of free parking provided by employers; and, use of a company car if needed for company business during the work day. The advantages to employers include: reduced health care costs because cyclists are physically fit; decreased absenteeism; increased productivity; reduced parking costs; lower company transportation bills; and, a greener corporate image. BUGs provide cycling information ranging from cycling maps to pamphlets and they raise cycle awareness. This guide includes cycling survey samples and examples of successful BUG activities across Canada. refs., tabs., figs.

  19. The effect of Dry Bed Training on behavioural problems in enuretic children

    NARCIS (Netherlands)

    Hira Sing, R.A.; van Leerdam, F.J.M.; Bolk-Bennink, L.F.; Koot, H.M.

    2002-01-01

    Children with nocturnal enuresis (n = 91) selected by school doctors in the Netherlands from 1991 to 1994 were included in a study to assess the course of behavioural problems especially when the children became dry after the Dry Bed Training (DBT) programme. The Child Behaviour Checklist (CBCL)

  20. The chemical volatiles (semiochemicals) produced by neo tropical stink bugs (Hemiptera: Pentatomidae)

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Maria C.B.; Pareja, Martin; Laumann, Raul A.; Borges, Miguel [EMBRAPA Recursos Geneticos e Biotecnologia, Brasilia, DF (Brazil). Nucleo Tematico Controle Biologico

    2008-09-15

    In recent years the growing concern about environmental changes and how we are using the natural resources have triggered a search for natural products as alternatives to synthetic pesticides. The stink bugs produce a wide variety of chemical compounds (semiochemicals) that show potential to manage these insects. The stink bugs Chinavia impicticornis (Stal), C. ubica (Rolston), Dichelops melacanthus (Dallas), Euschistus heros (F.), Piezodorus guildinii (Westwood), Thyanta perditor (Westwood) and Tibraca limbativentris (Stal) had their blends of defensive compounds evaluated both qualitative and quantitatively. The main compounds identified on the glands of Brazilian stink bugs are: 2-alkenals, mainly the E isomer; saturated aliphatic hydrocarbons; and 4 oxo-(E)-2-alkenals. The first sex attractant determined from a stink bug was obtained from Nezara viridula L., and consists on a mix of two isomers cis - and trans bisabolene-epoxides. Later the soybean stink bug E. heros was also studied and its sex attractant was identified as three esters methyl: 2,6,10-trimethyl decanoate, methyl 2,6,10-trimethyl dodecanoate, and methyl E2, Z4-decadienoate. Recently, three new Brazilian sting bugs were studied and had their sex attractant elucidated. Males of T. perditor produce the ester, methyl 2E, 4Z, 6Z-decatrienoate. Whereas, the stink bug, P. guildinii has as sexual pheromone, the sesquiterpene beta-sesqui phellandrene, and the stink bug T. limbativentris produces as sex attractant the zingiberenol. In this review we discuss the advances obtained on the behaviour and identification of sex and defensive compound of stink bugs from Brazilian crops and the application of this knowledge to manage the stink bugs. (author)

  1. The chemical volatiles (semiochemicals) produced by neo tropical stink bugs (Hemiptera: Pentatomidae)

    International Nuclear Information System (INIS)

    Moraes, Maria C.B.; Pareja, Martin; Laumann, Raul A.; Borges, Miguel

    2008-01-01

    In recent years the growing concern about environmental changes and how we are using the natural resources have triggered a search for natural products as alternatives to synthetic pesticides. The stink bugs produce a wide variety of chemical compounds (semiochemicals) that show potential to manage these insects. The stink bugs Chinavia impicticornis (Stal), C. ubica (Rolston), Dichelops melacanthus (Dallas), Euschistus heros (F.), Piezodorus guildinii (Westwood), Thyanta perditor (Westwood) and Tibraca limbativentris (Stal) had their blends of defensive compounds evaluated both qualitative and quantitatively. The main compounds identified on the glands of Brazilian stink bugs are: 2-alkenals, mainly the E isomer; saturated aliphatic hydrocarbons; and 4 oxo-(E)-2-alkenals. The first sex attractant determined from a stink bug was obtained from Nezara viridula L., and consists on a mix of two isomers cis - and trans bisabolene-epoxides. Later the soybean stink bug E. heros was also studied and its sex attractant was identified as three esters methyl: 2,6,10-trimethyl decanoate, methyl 2,6,10-trimethyl dodecanoate, and methyl E2, Z4-decadienoate. Recently, three new Brazilian sting bugs were studied and had their sex attractant elucidated. Males of T. perditor produce the ester, methyl 2E, 4Z, 6Z-decatrienoate. Whereas, the stink bug, P. guildinii has as sexual pheromone, the sesquiterpene beta-sesqui phellandrene, and the stink bug T. limbativentris produces as sex attractant the zingiberenol. In this review we discuss the advances obtained on the behaviour and identification of sex and defensive compound of stink bugs from Brazilian crops and the application of this knowledge to manage the stink bugs. (author)

  2. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... var c = 0; c Tips to prevent and treat bug bites Although most bug bites are harmless, some can spread dangerous diseases like Zika virus, dengue, Lyme disease, and malaria. Particularly if you’re ...

  3. Automated Bug Assignment: Ensemble-based Machine Learning in Large Scale Industrial Contexts

    OpenAIRE

    Jonsson, Leif; Borg, Markus; Broman, David; Sandahl, Kristian; Eldh, Sigrid; Runeson, Per

    2016-01-01

    Bug report assignment is an important part of software maintenance. In particular, incorrect assignments of bug reports to development teams can be very expensive in large software development projects. Several studies propose automating bug assignment techniques using machine learning in open source software contexts, but no study exists for large-scale proprietary projects in industry. The goal of this study is to evaluate automated bug assignment techniques that are based on machine learni...

  4. Biochemical characterization of digestive amylase of wheat bug ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-08-04

    Aug 4, 2009 ... ... Boyd et al., 2002). Wheat bug also feeds on different stage of developing grains. ... the grain during feeding, Wheat bug enzymes degrade gluten proteins and cause rapid relaxation of dough resulting in the production of .... A blank without substrate but with α-amylase extract and a control containing no ...

  5. Zero bugs and program faster

    CERN Document Server

    Thompson, Kate

    2015-01-01

    A book about programming, improving skill, and avoiding mistakes. The author spent two years researching every bug avoidance technique she could find. This book contains the best of them. If you want to program faster, with fewer bugs, and write more secure code, buy this book! "This is the best book I have ever read." - Anonymous reviewer "Four score and seven years ago this book helped me debug my server code." -Abraham Lincoln "Would my Javascript have memory leaks without this book? Would fishes fly without water?" -Socrates "This book is the greatest victory since the Spanish Armada, and the best about programming." -Queen Elizabeth

  6. WinBUGSio: A SAS Macro for the Remote Execution of WinBUGS

    Directory of Open Access Journals (Sweden)

    Michael K. Smith

    2007-09-01

    Full Text Available This is a macro which facilitates remote execution of WinBUGS from within SAS. The macro pre-processes data for WinBUGS, writes the WinBUGS batch-script, executes this script and reads in output statistics from the WinBUGS log-file back into SAS native format. The user specifies the input and output file names and directory path as well as the statistics to be monitored in WinBUGS. The code works best for a model that has already been set up and checked for convergence diagnostics within WinBUGS. An obvious extension of the use of this macro is for running simulations where the input and output files all have the same name but all that differs between simulation iterations is the input dataset. The functionality and syntax of the macro call are described in this paper and illustrated using a simple linear regression model.

  7. Evaluation of Blood Regimen on the Survival of Cimex lectularius L. Using Life Table Parameters

    Directory of Open Access Journals (Sweden)

    Edwin G. Rajotte

    2013-06-01

    Full Text Available Knowledge of bed bug development under varying conditions can lead to more sophisticated management techniques. Development rate, age and stage-specific life tables were compared for a laboratory strain (HS and field strain (ECL-05 of bed bug Cimex lectularius L. (Hemiptera: Heteroptera reared on two blood regimens: human or rabbit blood. Harlan and ECL-05 bed bugs reared on human blood had a life expectancy of 207 and 208 days respectively from the egg stage. Egg to adult development of HS bed bugs reared on human blood (~35 days was significantly longer than that of the ECL-05 strain (~33 days in the third, fourth, and fifth instars. The HS and ECL-05 bed bugs reared on rabbit blood had a life expectancy of 149 and 174 days respectively. Egg to adult development time of HS on rabbit blood (~52 days was significantly longer than ECL-05 (~37 days in every instar, and HS total life span was significantly shorter compared to ECL-05. Developmental differences based on strain and blood regimen suggest rabbit blood is an inferior blood source for colony maintenance, and strain has variable effects on bed bug development. Findings suggest that blood regimen should strongly be considered in bed bug colony maintenance.

  8. Insect-specific irreversible inhibitors of acetylcholinesterase in pests including the bed bug, the eastern yellowjacket, German and American cockroaches, and the confused flour beetle.

    Science.gov (United States)

    Polsinelli, Gregory A; Singh, Sanjay K; Mishra, Rajesh K; Suranyi, Robert; Ragsdale, David W; Pang, Yuan-Ping; Brimijoin, Stephen

    2010-09-06

    Insecticides directed against acetylcholinesterase (AChE) are facing increased resistance among target species as well as increasing concerns for human toxicity. The result has been a resurgence of disease vectors, insects destructive to agriculture, and residential pests. We previously reported a free cysteine (Cys) residue at the entrance to the AChE active site in some insects but not higher vertebrates. We also reported Cys-targeting methanethiosulfonate molecules (AMTSn), which, under conditions that spared human AChE, caused total irreversible inhibition of aphid AChE, 95% inhibition of AChE from the malaria vector mosquito (Anopheles gambia), and >80% inhibition of activity from the yellow fever mosquito (Aedes aegypti) and northern house mosquito (Culex pipiens). We now find the same compounds inhibit AChE from cockroaches (Blattella germanica and Periplaneta americana), the flour beetle (Tribolium confusum), the multi-colored Asian ladybird beetle (Harmonia axyridis), the bed bug (Cimex lectularius), and a wasp (Vespula maculifrons), with IC(50) values of approximately 1-11muM. Our results support further study of Cys-targeting inhibitors as conceptually novel insecticides that may be free of resistance in a range of insect pests and disease vectors and, compared with current compounds, should demonstrate much lower toxicity to mammals, birds, and fish. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  9. Catching the Bug: How Virtual Coaching Improves Teaching

    Science.gov (United States)

    Allen, Megan

    2014-01-01

    In this article the author describes virtual coaching and why it is so effective. The following six points of virtual coaching are explained: (1) Also known as bug-in-ear coaching, virtual coaching is not new; (2) Virtual coaching can save money and time; (3) Bug-in-ear coaching increases the frequency of observations for novice teachers; (4) It…

  10. Ecosystem-Based Incorporation of Nectar-Producing Plants for Stink Bug Parasitoids

    Directory of Open Access Journals (Sweden)

    Glynn Tillman

    2017-06-01

    Full Text Available Adult parasitoids of pest insects rely on floral resources for survival and reproduction, but can be food-deprived in intensively managed agricultural systems lacking these resources. Stink bugs are serious pests for crops in southwest Georgia. Provisioning nectar-producing plants for parasitoids of stink bugs potentially can enhance biocontrol of these pests. Knowledge of spatial and temporal availability and distribution of stink bugs in host plants is necessary for appropriate timing and placement of flowering plants in agroecosystems. Stink bugs move between closely associated host plants throughout the growing season in response to deteriorating suitability of their host plants. In peanut-cotton farmscapes, stink bugs develop in peanut, and subsequently the adults disperse into adjacent cotton. Parasitism of Nezara viridula (L. adults by Trichopoda pennipes (F. at the peanut-cotton interface was significantly higher in cotton with a strip of milkweed or buckwheat between the two crops than in cotton alone. Milkweed and buckwheat also provided nectar to a wide range of insect pollinators. Monarch butterflies fed on milkweed. When placed between peanut and cotton, a strip of soybean was an effective trap crop for cotton, reducing economic damage. Incorporation of buckwheat near soybean enhanced parasitism of Euschistus servus (Say eggs by Telenomus podisi Ashmead in cotton. In conclusion, nectar provision enhances biocontrol of stink bugs, acts together with other management tactics for stink bug control, and aids in conservation of natural enemies, insect pollinators, and the monarch butterfly.

  11. WYSIWIB: A Declarative Approach to Finding Protocols and Bugs in Linux Code

    DEFF Research Database (Denmark)

    Lawall, Julia Laetitia; Brunel, Julien Pierre Manuel; Hansen, Rene Rydhof

    2008-01-01

    the tools to be able to find specific kinds of bugs. In this paper, we propose a declarative approach based on a control-flow based program search engine. Our approach is WYSIWIB (What You See Is Where It Bugs), since the programmer is able to express specifications for protocol and bug finding using...

  12. How Does Bug-Handling Effort Differ Among Different Programming Languages?

    OpenAIRE

    Zhang, Jie; Li, Feng; Hao, Dan; Wang, Meng; Zhang, Lu

    2018-01-01

    Handling bugs is an essential part of software development. The impact of programming language on this task has long been a topic of much debate. For example, some people hold the view that bugs in Python are easy to handle because its code is easy to read and understand, while some others believe the absence of static typing in Python will lead to higher bug-handling effort. This paper presents the first large-scale study to investigate whether the ecosystems of different (categories of) pro...

  13. Insects: Bugged Out!

    Science.gov (United States)

    Piehl, Kathy

    2011-01-01

    Insects really need no introduction. They have lived on earth much longer than humans and vastly outnumber people and all other animal species combined. People encounter them daily in their houses and yards. Yet, when children want to investigate insects, books can help them start their explorations. "Paleo Bugs" carries readers back to the time…

  14. A Contribution to the Problem of Initiation of a Combustion Source in an Oil-Saturated Bed

    Science.gov (United States)

    Koznacheev, I. A.; Dobrego, K. V.

    2013-11-01

    The problem on in-situ self-ignition of an oil-saturated bed under the conditions of forced filtration of an oxygen-containing gas has been solved with analytical and numerical methods with account of the burnout of a deficient gas component. The influence of the burnout of this component and of convective removal of heat from the bed on the time of its self-ignition has been determined. Recommendations for the optimum regime of initiation of the self-ignition of the bed with account of variation of the blast flow rate and the oxygen content have been given.

  15. A methodology for quantitatively managing the bug fixing process using Mahalanobis Taguchi system

    Directory of Open Access Journals (Sweden)

    Boby John

    2015-12-01

    Full Text Available The controlling of bug fixing process during the system testing phase of software development life cycle is very important for fixing all the detected bugs within the scheduled time. The presence of open bugs often delays the release of the software or result in releasing the software with compromised functionalities. These can lead to customer dissatisfaction, cost overrun and eventually the loss of market share. In this paper, the authors propose a methodology to quantitatively manage the bug fixing process during system testing. The proposed methodology identifies the critical milestones in the system testing phase which differentiates the successful projects from the unsuccessful ones using Mahalanobis Taguchi system. Then a model is developed to predict whether a project is successful or not with the bug fix progress at critical milestones as control factors. Finally the model is used to control the bug fixing process. It is found that the performance of the proposed methodology using Mahalanobis Taguchi system is superior to the models developed using other multi-dimensional pattern recognition techniques. The proposed methodology also reduces the number of control points providing the managers with more options and flexibility to utilize the bug fixing resources across system testing phase. Moreover the methodology allows the mangers to carry out mid- course corrections to bring the bug fixing process back on track so that all the detected bugs can be fixed on time. The methodology is validated with eight new projects and the results are very encouraging.

  16. Pheromones of milkweed bugs (Heteroptera: Lygaeidae) attract wayward plant bugs: Phytocoris mirid sex pheromone.

    Science.gov (United States)

    Zhang, Qing-He; Aldrich, Jeffrey R

    2003-08-01

    The synthetic aggregation pheromone of the large milkweed bug, Oncopeltus fasciatus (Dallas) (Lygaeinae), also attracted males of the plant bug, Phytocoris difficilis Knight (Miridae). Field testing partial blends against the six-component blend comprising the Oncopeltus pheromone showed that cross-attraction of P. difficilis males was due to synergism between (E)-2-octenyl acetate and (E,E)-2,4-hexadienyl acetate. Hexyl acetate was abundant in the metathoracic scent gland (MSG) secretion of P. difficilis males, but because female P. difficilis could not initially be found in the field, further combinatorial tests were guided by prior research on the pheromones of two Phytocoris species in the western United States. The combination of hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates was as attractive to P. difficilis males as the milkweed bug pheromone, yet no milkweed bugs were drawn to this blend. Gas chromatographic (GC)-electroantennographic detection (EAD) and GC-mass spectrometric (MS) analyses of female P. difficilis MSGs determined that their secretion contained predominantly hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates (all strongly EAD-active)-the latter two compounds found only in trace amounts from males-plus five minor female-specific compounds, three of which were EAD-active. (E,E)-2,4-Hexadienyl acetate was not detected from P. difficilis females or males. The blend of the three major components, hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates (2:1.5:1 by volume), was as attractive as the blend of all six EAD-active compounds identified from females, indicating that this ternary blend constitutes the sex pheromone of P. difficilis. Hexyl acetate with (E)-2-octenyl acetate also attracted males of another species, P. breviusculus Reuter, but addition of (E)-2-hexenyl acetate and/or (E,E)-2,4-hexadienyl acetate inhibited attraction of P. breviusculus males. Attraction of P. difficilis males occurred mainly during the first half of scotophase. The

  17. Production of polycrystalline silicon by fluidized-bed-problems and recent progress of study

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Toshinori

    1988-10-01

    Concerning the production of polycrystalline silicon from SiH/sub 4/ by applying fluidized bed reaction, recent progress of study, problems involved, and countermeasures to them were reported. For the experiment, stainless tube with 50mm inside diameter attached with electric heater on the wall as auxillary heat source was used to measure the temperature distribution in the bed. As the diluting gas, hydrogen and argon were used to investigate the effect of diluent gas and it was understood that sort of diluent gas affected on the crogging and reaction rate. It was indicated that, in the fluidized bed reaction which gave large depositing area and high productivity, contamination was easily occurred. Observation of fine powder by electronic-microscope revealed that different diluent caused the difference of fine powder shape and that the higher the reaction temperature the more fine powder was produced. Crogging condition was affected by tower diameter, together with temperature and fluidizing conditions. In addition, two recent patents were introduced. 11 references, 10 figures.

  18. Synthèse bibliographique sur le comportement de recherche de l'hôte chez la punaise de lit (Cimex lectularius et applications dans le cadre de la lutte intégrée

    Directory of Open Access Journals (Sweden)

    Legrand, P.

    2016-01-01

    Full Text Available Host-seeking behavior in the bed bug (Cimex lectularius and applications in integrated pest management. A review. Description of the subject. This study analyzes host-seeking behavior in the common bed bug, Cimex lectularius, paying particular attention to human stimuli involved in this orientation process. The potential applications in integrated pest management are discussed. Literature. The common bed bug is an obligate hematophagous that has been associated with humans for millennia. When searching for food, this insect relies for orientation on signals produced by its hosts. Carbon dioxide emitted by human respiration is more attractive to bugs than body heat. The response of bed bugs to other volatile organic compounds released by the human body has been tested, but their perception and behavioral impact are not always studied together, and some discrepancies occasionally appear. Conclusions. Currently, carbon dioxide is the most efficient lure for bed bugs, although real human bait is more attractive. Some home-made traps baited with dry ice are more efficient than other traps using complicated chemical blends. Dry ice seems to be more efficient as a lure than complex chemical blends, and it can be used in simple traps. Our knowledge of host-seeking behavior in bed bugs is still partial and new questions are constantly arising. Further efforts in the study of the chemical ecology of this process are needed in order to improve the management of this pest. The control of bed bugs in European countries appears to be a major challenge for the years to come.

  19. Aggregation and Association of NDVI, Boll Injury, and Stink Bugs in North Carolina Cotton.

    Science.gov (United States)

    Reisig, Dominic D; Reay-Jones, F P F; Meijer, A D

    2015-01-01

    Sampling of herbivorous stink bugs in southeastern U.S. cotton remains problematic. Remote sensing was explored to improve sampling of these pests and associated boll injury. Two adjacent 14.5-ha cotton fields were grid sampled in 2011 and 2012 by collecting stink bug adults and bolls every week during the third, fourth, and fifth weeks of bloom. Satellite remote sensing data were collected during the third week of bloom during both years, and normalized difference vegetation index (NDVI) values were calculated. Stink bugs were spatially aggregated on the third week of bloom in 2011. Boll injury from stink bugs was spatially aggregated during the fourth week of bloom in 2012. The NDVI values were aggregated during both years. There was a positive association and correlation between stink bug numbers and NDVI values, as well as injured bolls and NDVI values, during the third week of bloom in 2011. During the third week of bloom in 2012, NDVI values were negatively correlated with stink bug numbers. During the fourth week of bloom in 2011, stink bug numbers and boll injury were both positively associated and correlated with NDVI values. During the fourth week of bloom in 2012, stink bugs were negatively correlated with NDVI values, and boll injury was negatively associated and correlated with NDVI values. This study suggests the potential of remote sensing as a tool to assist with sampling stink bugs in cotton, although more research is needed using NDVI and other plant measurements to predict stink bug injury. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.

  20. Studies towards the sex pheromone of the green capsid bug

    NARCIS (Netherlands)

    Drijfhout, F.P.

    2001-01-01

    The green capsid bug, Lygocoris pabulinus (L.) (Heteroptera: Miridae) is a serious pest in fruit orchards, which is difficult to control. Because it is difficult to determine the actual population density, fruit growers apply insecticides against the green capsid bug on

  1. WYSIWYB: A Declarative Approach to Finding API Protocols and Bugs in Linux Code

    DEFF Research Database (Denmark)

    Lawall, Julia; Lawall, Julia; Palix, Nicolas

    2009-01-01

    the tools to be able to find specific kinds of bugs. In this paper, we propose a declarative approach based on a control-flow based program search engine. Our approach is WYSIWIB (What You See Is Where It Bugs), since the programmer is able to express specifications for protocol and bug finding using...

  2. WYSIWIB: A Declarative Approach to Finding API Protocols and Bugs in Linux Code

    DEFF Research Database (Denmark)

    Lawall, Julia; Brunel, Julien Pierre Manuel; Palix, Nicolas Jean-Michel

    2009-01-01

    the tools on specific kinds of bugs and to relate the results to patterns in the source code. We propose a declarative approach to bug finding in Linux OS code using a control-flow based program search engine. Our approach is WYSIWIB (What You See Is Where It Bugs), since the programmer expresses...

  3. Traveler's Health: Avoid Bug Bites

    Science.gov (United States)

    ... Safety Road Safety - 8 Steps MERS Health Advisory poster MERS Pictogram CDC Guide for Healthy Travel Website ... other accommodations that are air conditioned or have good window and door screens so bugs can’t ...

  4. An automated approach for finding variable-constant pairing bugs

    DEFF Research Database (Denmark)

    Lawall, Julia; Lo, David

    2010-01-01

    program-analysis and data-mining based approach to identify the uses of named constants and to identify anomalies in these uses.  We have applied our approach to a recent version of the Linux kernel and have found a number of bugs affecting both correctness and software maintenance.  Many of these bugs...... have been validated by the Linux developers....

  5. Improvement on the accuracy of beam bugs in linear induction accelerator

    International Nuclear Information System (INIS)

    Xie Yutong; Dai Zhiyong; Han Qing

    2002-01-01

    In linear induction accelerator the resistive wall monitors known as 'beam bugs' have been used as essential diagnostics of beam current and location. The author presents a new method that can improve the accuracy of these beam bugs used for beam position measurements. With a fine beam simulation set, this method locates the beam position with an accuracy of 0.02 mm and thus can scale the beam bugs very well. Experiment results prove that the precision of beam position measurements can reach submillimeter degree

  6. Apocalypse deterred : oil and gas community pulls out ahead in vaccinating itself against Y2K, the millennium bug

    International Nuclear Information System (INIS)

    Gordon, M.

    1999-01-01

    Results of a survey of the membership of the Canadian Association of Petroleum Producers (CAPP) regarding efforts to deal with the threat posed by the Y2K millennium bug are reviewed. Survey results reveal that CAPP's 170 member companies take the year 2000 date rollover very seriously, and the vast majority (99 per cent) have formal action plans to deal with the threat. The vast majority of plans have components that take into account the effects of the computer glitch on inventories, compliance and risk assessment matters, correction and replacement. All are doing testing and assessments involving business partners, and are developing contingency plans to keep operating if any problems develop despite all the efforts currently underway. Test results to date show low failure rates in field production control equipment. The current focus is on contingency plans for higher risk items. The downstream sector of the industry, involving transportation, distribution and retail marketing, is making similar efforts to minimize the threat of the Y2K bug, sometimes to the point of switching to new and improved equipment to vaccinate all its major operations against the expected computer failure. The cost of coping with the millennium bug is colossal. Canadian governments expect the cost to reach three billion dollars to purge the bug from government operations alone. Estimates of world-wide cost run to 530 billion dollars, plus another trillion dollars to clean up the aftermath of infections. Nevertheless, the current assessment is that the back of the problem has been broken at least in Canada, the United States and Western Europe. Nevertheless, there is no justification for complacency just yet

  7. Synthèse bibliographique sur le comportement de recherche de l'hôte chez la punaise de lit (Cimex lectularius) et applications dans le cadre de la lutte intégrée

    OpenAIRE

    Legrand, P.; Verheggen, F.; Haubruge, E.; Francis, F.

    2016-01-01

    Host-seeking behavior in the bed bug (Cimex lectularius) and applications in integrated pest management. A review. Description of the subject. This study analyzes host-seeking behavior in the common bed bug, Cimex lectularius, paying particular attention to human stimuli involved in this orientation process. The potential applications in integrated pest management are discussed. Literature. The common bed bug is an obligate hematophagous that has been associated with humans for millennia. Whe...

  8. Hybridization and adaptation to introduced balloon vines in an Australian soapberry bug.

    Science.gov (United States)

    Andres, J A; Thampy, P R; Mathieson, M T; Loye, J; Zalucki, M P; Dingle, H; Carroll, S P

    2013-12-01

    Contemporary adaptation of plant feeding insects to introduced hosts provides clear cases of ecologically based population divergence. In most cases the mechanisms permitting rapid differentiation are not well known. Here we study morphological and genetic variation associated with recent shifts by the Australian soapberry bug Leptocoris tagalicus onto two naturalized Neotropical balloon vines, Cardiospermum halicacabum and C. grandiflorum that differ in time since introduction. Our results show that these vines have much larger fruits than the native hosts (Whitewood tree -Atalaya hemiglauca- and Woolly Rambutan -Alectryon tomentosus-) and that bugs living on them have evolved significantly longer beaks and new allometries. Genetic analyses of mitochondrial haplotypes and amplified fragment length polymorphic (AFLP) markers indicate that the lineage of bugs on the annual vine C. halicacabum, the older introduction, is intermediate between the two subspecies of L. tagalicus found on native hosts. Moreover, where the annual vine and Whitewood tree co-occur, the morphology and genomic composition of the bugs are similar to those occurring in allopatry. These results show that hybridization provided the genetic elements underlying the strongly differentiated 'Halicacabum bugs'. In contrast, the bugs feeding on the recently introduced perennial balloon vine (C. grandiflorum) showed no evidence of admixture, and are genetically indistinguishable from the nearby populations on a native host. © 2013 John Wiley & Sons Ltd.

  9. Bug tracking and project management system application in an electronic design company

    Directory of Open Access Journals (Sweden)

    Sadık ARSLAN

    2016-05-01

    Full Text Available In this study, commercially available Bug Tracking and Management Information Systems has been investigated in a comprehensive manner. The systems that commonly used described in detail. Bug Tracking and Project Management Systems requirements analysis of medium-sized companies and Kentkart Ege Electronic which is an Information Technology company has been made. Obtained by the analysis requirements, the appropriate tools are selected for system application. JIRA that a product of Atlassian company was determined as a Bug Tracking and Project Management application tool. In this study, JIRA system adapted to the requirements, Bug Tracking and Project Management systems is designed in a structure which can be easily used by R&D employees. Cost-Benefit analysis is done and using this project was determined to be quite useful.

  10. Diversity of some endophytic fungi associated with rice black bug Paraeucosmetus pallicornis on rice plant

    OpenAIRE

    Nur, Amin; La Daha; Nurariaty, Agus; Ade, Rosmana; Muh., Fadlan

    2015-01-01

    A new rice insect pest was sighted in some rice producing areas of South Sulawesi Province, Indonesia. This pest is rice black bugs Paraeucosmetus pallicornis. The research aimed to isolation of fungi associated with rice black bugs Paraeucosmetus pallicornis, so as to know the cause of a bitter taste to the rice. The isolation of the fungi consist of three kinds of treatment, namely rice black bugs without sterilization, with sterilization and rice black bugs cut and sterilized. The resul...

  11. On the Problem of Filtration to an Imperfect Gallery in a Pressureless Bed

    Science.gov (United States)

    Bereslavskii, É. N.; Dudina, L. M.

    2018-01-01

    The problem of plane steady-state filtration in a pressureless bed to an imperfect gallery in the presence of evaporation from the flow free surface is considered. To study such type of flow, a mixed boundary-value problem of the theory of analytical functions is formulated and solved with application of the Polubarinova-Kochina method. Based on the model suggested, an algorithm for computing the discharge of the gallery and the ordinate of free surface emergence to the impermeable screen is developed. A detailed hydrodynamic analysis of the influence of all physical parameters of the model on the desired filtration characteristics is given.

  12. Stability of Spatial Distributions of Stink Bugs, Boll Injury, and NDVI in Cotton.

    Science.gov (United States)

    Reay-Jones, Francis P F; Greene, Jeremy K; Bauer, Philip J

    2016-10-01

    A 3-yr study was conducted to determine the degree of aggregation of stink bugs and boll injury in cotton, Gossypium hirsutum L., and their spatial association with a multispectral vegetation index (normalized difference vegetation index [NDVI]). Using the spatial analysis by distance indices analyses, stink bugs were less frequently aggregated (17% for adults and 4% for nymphs) than boll injury (36%). NDVI values were also significantly aggregated within fields in 19 of 48 analyses (40%), with the majority of significant indices occurring in July and August. Paired NDVI datasets from different sampling dates were frequently associated (86.5% for weekly intervals among datasets). Spatial distributions of both stink bugs and boll injury were less stable than for NDVI, with positive associations varying from 12.5 to 25% for adult stink bugs for weekly intervals, depending on species. Spatial distributions of boll injury from stink bug feeding were more stable than stink bugs, with 46% positive associations among paired datasets with weekly intervals. NDVI values were positively associated with boll injury from stink bug feeding in 11 out of 22 analyses, with no significant negative associations. This indicates that NDVI has potential as a component of site-specific management. Future work should continue to examine the value of remote sensing for insect management in cotton, with an aim to develop tools such as risk assessment maps that will help growers to reduce insecticide inputs. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Species composition, monitoring, and feeding injury of stink bugs (Heteroptera: Pentatomidae) in blackberry.

    Science.gov (United States)

    Brennan, S A; Liburd, O E; Eger, J E; Rhodes, E M

    2013-04-01

    Blackberry (Rubus spp.) production in Florida has increased > 100% within the past two decades. and several insect pests, including stink bugs (Heteroptera: Pentatomidae), have been observed feeding on this crop. The objectives for this study were to determine the stink bug species present in blackberry; to develop monitoring tools for stink bugs in blackberry; and to describe feeding injury to blackberries by Euschistus quadrator Rolston, a relatively new stink bug pest to Florida, that has spread throughout the state. In a field survey, E. quadrator was the most abundant stink bug species, followed by Euschistus servus Say, Euschistus obscurus (Palisot de Beauvois), Thyanta custator (F.), Proxys punctulatus (Palisot de Beauvois), and Podisus maculiventris Say. Yellow pyramid traps caught more stink bugs than tube traps with or without the addition of Euschistus spp. pheromone lures. There were no statistical differences between traps baited with a Trécé Pherocon Centrum lure, a Suterra Scenturion lure, and an unbaited trap. These results were supported by Y-tube olfactometer assays with E. quadrator where there were no differences between pheromone baited lures and a control. Injury to berries caused by E. quadrator adults and third instars was similar, and both adults and third instars fed more on green berries compared with turning berries. In addition, adults fed more on green berries compared with ripe fruit. The most common injury to green berries was discoloration. In contrast, misshapen drupelets were commonly seen on turning and ripe berries. The potential for managing stink bugs in blackberries to prevent them from reaching damaging levels is discussed.

  14. Green plant bug from South Texas gets a common name - the "verde plant" bug

    Science.gov (United States)

    Some cotton producers from south Texas and the Gulf Coast regions have been unfortunate over the last few years because they have had to deal with a green plant bug, Creontiades signatus, that will feed on cotton fruit. The insect was initially, and erroneously, thought to be Creontiades dilutus, an...

  15. Bug22 influences cilium morphology and the post-translational modification of ciliary microtubules

    Directory of Open Access Journals (Sweden)

    Teresa Mendes Maia

    2014-01-01

    Cilia and flagella are organelles essential for motility and sensing of environmental stimuli. Depending on the cell type, cilia acquire a defined set of functions and, accordingly, are built with an appropriate length and molecular composition. Several ciliary proteins display a high degree of conservation throughout evolution and mutations in ciliary genes are associated with various diseases such as ciliopathies and infertility. Here, we describe the role of the highly conserved ciliary protein, Bug22, in Drosophila. Previous studies in unicellular organisms have shown that Bug22 is required for proper cilia function, but its exact role in ciliogenesis has not been investigated yet. Null Bug22 mutant flies display cilia-associated phenotypes and nervous system defects. Furthermore, sperm differentiation is blocked at the individualization stage, due to impaired migration of the individualization machinery. Tubulin post-translational modifications (PTMs such as polyglycylation, polyglutamylation or acetylation, are determinants of microtubule (MT functions and stability in centrioles, cilia and neurons. We found defects in the timely incorporation of polyglycylation in sperm axonemal MTs of Bug22 mutants. In addition, we found that depletion of human Bug22 in RPE1 cells resulted in the appearance of longer cilia and reduced axonemal polyglutamylation. Our work identifies Bug22 as a protein that plays a conserved role in the regulation of PTMs of the ciliary axoneme.

  16. Health Information in Amharic (Amarɨñña / አማርኛ )

    Science.gov (United States)

    ... Bed Bug Control in Residences - Amarɨñña / አማርኛ (Amharic) MP3 Minnesota Department of Agriculture Vacuuming to Capture Bed ... Vacuuming to Capture Bed Bugs - Amarɨñña / አማርኛ (Amharic) MP3 Minnesota Department of Agriculture Benefits of Exercise Health ...

  17. Bug Distribution and Statistical Pattern Classification.

    Science.gov (United States)

    Tatsuoka, Kikumi K.; Tatsuoka, Maurice M.

    1987-01-01

    The rule space model permits measurement of cognitive skill acquisition and error diagnosis. Further discussion introduces Bayesian hypothesis testing and bug distribution. An illustration involves an artificial intelligence approach to testing fractions and arithmetic. (Author/GDC)

  18. Comparing Fine-Grained Source Code Changes And Code Churn For Bug Prediction

    NARCIS (Netherlands)

    Giger, E.; Pinzger, M.; Gall, H.C.

    2011-01-01

    A significant amount of research effort has been dedicated to learning prediction models that allow project managers to efficiently allocate resources to those parts of a software system that most likely are bug-prone and therefore critical. Prominent measures for building bug prediction models are

  19. Usage of data warehouse for analysing software's bugs

    Science.gov (United States)

    Živanov, Danijel; Krstićev, Danijela Boberić; Mirković, Duško

    2017-07-01

    We analysed the database schema of Bugzilla system and taking into account user's requirements for reporting, we presented a dimensional model for the data warehouse which will be used for reporting software defects. The idea proposed in this paper is not to throw away Bugzilla system because it certainly has many strengths, but to make integration of Bugzilla and the proposed data warehouse. Bugzilla would continue to be used for recording bugs that occur during the development and maintenance of software while the data warehouse would be used for storing data on bugs in an appropriate form, which is more suitable for analysis.

  20. Integrating Symbolic Execution with Sensornet Simulation for Efficient Bug Finding

    OpenAIRE

    Österlind, Fredrik; Sasnauskas, Raimondas; Dustmann, Oscar Soria; Dunkels, Adam; Wehrle, Klaus

    2010-01-01

    High-coverage testing of sensornet applications is vital for pre-deployment bug cleansing, but has previously been difficult due to the limited set of available tools. We integrate the KleeNet symbolic execution engine with the COOJA network simulator to allow for straight-forward and intuitive high-coverage testing initiated from a simulation environment. A tight coupling of simulation and testing helps detect, narrow down, and fix complex interaction bugs in an early ...

  1. Comparative Performance Analysis of Machine Learning Techniques for Software Bug Detection

    OpenAIRE

    Saiqa Aleem; Luiz Fernando Capretz; Faheem Ahmed

    2015-01-01

    Machine learning techniques can be used to analyse data from different perspectives and enable developers to retrieve useful information. Machine learning techniques are proven to be useful in terms of software bug prediction. In this paper, a comparative performance analysis of different machine learning techniques is explored f or software bug prediction on public available data sets. Results showed most of the mac ...

  2. Area-wide management approach for tarnished plant bug in the Mississippi Delta

    Science.gov (United States)

    The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is the major insect pest of cotton, Gossypium hirsutum (L.), within the Mid-South region. From 2001 to 2012, the tarnished plant bug has been the number one insect pest of cotton in Louisiana and Mississippi in eleven and nine of those...

  3. ASSESSMENT OF HEAVY METALS CONTENTS IN BOTTOM SEDIMENTS OF BUG RIVER

    Directory of Open Access Journals (Sweden)

    Elżbieta Skorbiłowicz

    2014-07-01

    Full Text Available The development of industry, agriculture, and transport contributes to an increased environmental pollution by heavy metals. The aim of the study was preliminary assessment of the contents of selected metals (lead, cobalt, copper, chromium, cadmium and nickel in the sediments of Bug river. The study comprised part of the river flowing through Poland. It was found that the Bug river sediments are not contaminated in respect to the content of tested metals. Based on the analysis of the study results, these metals can be lined up in the following order: Cr > Pb > Cu > Ni > Co > Cd. Statistical analysis showed that copper and chromium occur in Bug river sediments in forms bindings with organic matter in majority of cases. The granulometric analysis of sediments from Bug river revealed the largest percentage of two fractions: 1.0–0.2 mm with average of 47.7 ± 19.77% and 0.2–0.1 mm with average of 20.6 ± 7.7%. These are the dominant fractions with the accumulation of metals in river sediments, which has been confirmed by statistical analysis.

  4. Cytogenetika štěnic (Cimicidae) jako modelových ploštic (Insecta: Heteroptera)

    OpenAIRE

    Sadílek, David

    2010-01-01

    Cytogenetics of bed bugs (Cimicidae) as a model true bugs (Insecta: Heteroptera) The thesis provides current opinions about a phylogeny of bed bugs, family Cimicidae, and their classification within the order Heteroptera. There are briefly summarized cytological data about the order Heteroptera, known karyotypes of the cimicid subfamilies and introduction to cytogenetics of species Cimex lectularius Linnaeus, 1758. Heteroptera species differ from other organisms by holokinetic chromosomes, a ...

  5. Agglomeration of bed material: Influence on efficiency of biofuel fluidized bed boiler

    Directory of Open Access Journals (Sweden)

    Ryabov Georgy A.

    2003-01-01

    Full Text Available The successful design and operation of a fluidized bed combustor requires the ability to control and mitigate ash-related problems. The main ash-related problem of biomass filing boiler is agglomeration. The fluidized bed boiler with steam capacity of 66 t/h (4 MPa, 440 °C was started up at the Arkhangelsk Paper-Pi dp-Plant in 2001. This boiler was manufactured by the Russian companies "Energosofin" and "Belenergomash" and installed instead of the existing boiler with mechanical grate. Some constructional elements and steam drum of existing boiler remained unchanged. The primary air fan was installed past the common air fan, which supply part of the air into 24 secondary airports. First operating period shows that the bed material is expanded and then operator should increase the primary air rate, and the boiler efficiency dramatically decreases. Tills paper presents some results of our investigations of fuel, bed and fly ash chemical compositions and other characteristics. Special experiments were carried out to optimize the bed drain flow rate. The influence of secondly air supply improvement on mixing with the main flow and boiler efficiency are given.

  6. Degree Day Requirements for Kudzu Bug (Hemiptera: Plataspidae), a Pest of Soybeans.

    Science.gov (United States)

    Grant, Jessica I; Lamp, William O

    2018-04-02

    Understanding the phenology of a new potential pest is fundamental for the development of a management program. Megacopta cribraria Fabricius (Hemiptera: Plataspidae), kudzu bug, is a pest of soybeans first detected in the United States in 2009 and in Maryland in 2013. We observed the phenology of kudzu bug life stages in Maryland, created a Celsius degree-day (CDD) model for development, and characterized the difference between microhabitat and ambient temperatures of both kudzu, Pueraria montana (Lour.) Merr. (Fabales: Fabaceae) and soybeans, Glycine max (L.) Merrill (Fabales: Fabaceae). In 2014, low population numbers yielded limited resolution from field phenology observations. We observed kudzu bug populations persisting within Maryland; but between 2013 and 2016, populations were low compared to populations in the southeastern United States. Based on the degree-day model, kudzu bug eggs require 80 CDD at a minimum temperature of 14°C to hatch. Nymphs require 545 CDD with a minimum temperature of 16°C for development. The CDD model matches field observations when factoring a biofix date of April 1 and a minimum preoviposition period of 17 d. The model suggests two full generations per year in Maryland. Standard air temperature monitors do not affect model predictions for pest management, as microhabitat temperature differences did not show a clear trend between kudzu and soybeans. Ultimately, producers can predict the timing of kudzu bug life stages with the CDD model for the use of timing management plans in soybean fields.

  7. Prevention of Bed Agglomeration Problems in a Fluidized Bed Boiler by Finding the Trigging Value of Sewage Sludge Dosage Added to Combustion of Biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Kajsa; Gervind, Pernilla

    2009-07-01

    Agglomeration of bed sand is a common problem during combustion of biofuels with high ash content in fluidized bed boilers. Former studies have shown that co-combustion of biofuels with sewage sludge increases the agglomeration temperature. Sewage sludge has a low heating value and high ash content. It would therefore be better to use sludge as an additive to the combustion than as a co-combusted biofuel. In this study the trigging value of sludge addition to the combustion of some biofuel was investigated. The effect of adding sludge with different precipitation chemicals, iron sulphate and aluminium sulphate, was investigated. The biofuels used for the experiments were bark, refused derived fuel (RDF) and a mixture of wood and straw, 75/25 % on energy basis. All experiments were carried out in a laboratory scale fluidized bed reactor. Analyses of chemical composition of bed sand and SEM/EDX analyses were performed after the combustion. Eventually agglomeration tests were performed in order to find the agglomeration temperature of the samples. Some of the samples sintered during the combustion and were not tested for the agglomeration temperature. SEM/EDX showed that all samples of bed sand contained sand particles with more or less coatings. In some cases the coatings seemed to consist of one dense inner layer and one more porous outer layer. From SEM/EDX and chemical composition analyses it was found that the total amount of phosphorous in the bed sand samples was increased with an increased addition of sludge in all experiments. The concentration of phosphorous was especially higher in the outer layers/coatings. It was also found that elements from the sludge seem to get caught by a sticky layer at the bed sand surface and form a non-sticky or less sticky layer that prevents agglomeration. The total amount of aluminium was increased with an increased addition of sludge for the wood/straw samples, while it increased with an increased amount of combusted fuel for

  8. Fixed-bed Reactor Dynamics and Control - A Review

    DEFF Research Database (Denmark)

    Jørgensen, S. B.

    1986-01-01

    The industrial diversity of fixed bed reactors offers a challenging and relevant set of control problems. These intricate problems arise due to the rather complex dynamics of fixed bed reactors and to the complexity of actual reactor configurations. Many of these control problems are nonlinear...... and multi-variable. During the last decade fixed bed reactor control strategies have been proposed and investigated experimentally. This paper reviews research on these complex control problems with an emphasis upon solutions which have been demon-strated to work in the laboratory and hold promise...

  9. Bringing Up Girls in Science (BUGS): The Effectiveness of an Afterschool Environmental Science Program for Increasing Female Students' Interest in Science Careers

    Science.gov (United States)

    Tyler-Wood, Tandra; Ellison, Amber; Lim, Okyoung; Periathiruvadi, Sita

    2012-02-01

    Bringing Up Girls in Science (BUGS) was an afterschool program for 4th and 5th grade girls that provided authentic learning experiences in environmental science as well as valuable female mentoring opportunities in an effort to increase participants' academic achievement in science. BUGS participants demonstrated significantly greater amounts of gain in science knowledge as measured by the Iowa Test of Basic Skills in Science (ITBS-S). The original BUGS participants and contrasts have now completed high school and entered college, allowing researchers to assess the long-term impact of the BUGS program. Fourteen former BUGS participants completed two instruments to assess their perceptions of science and science, technology, engineering, and mathematics (STEM) careers. Their results were compared to four contrast groups composed entirely of females: 12 former BUGS contrasts, 10 college science majors, 10 non-science majors, and 9 current STEM professionals. Results indicate that BUGS participants have higher perceptions of science careers than BUGS contrasts. There were no significant differences between BUGS participants, Science Majors, and STEM professionals in their perceptions of science and STEM careers, whereas the BUGS contrast group was significantly lower than BUGS participants, Science Majors, and STEM Professionals. Additional results and implications are discussed within.

  10. Association of Verde plant bug, Creontiades signatus (Hemiptera: Miridae), with cotton boll rot

    Science.gov (United States)

    Cotton along the Gulf Coast of south Texas has experienced loss from cotton boll rot especially during the last 10 to 15 years, and stink bugs and plant bugs (Hemiptera: Pentatomidae and Miridae) that feed on cotton bolls have been suspected in introducing the disease. A replicated grower field surv...

  11. Fluidised bed heat exchangers

    International Nuclear Information System (INIS)

    Elliott, D.E.; Healey, E.M.; Roberts, A.G.

    1974-01-01

    Problems that have arisen during the initial stages of development of fluidised bed boilers in which heat transfer surfaces are immersed in fluidised solids are discussed. The very high heat transfer coefficients that are obtained under these conditions can be exploited to reduce the total heat transfer surface to a fraction of that in normal boilers. However, with the high heat flux levels involved, tube stressing becomes more important and it is advantageous to use smaller diameter tubes. One of the initial problems was that the pumping power absorbed by the fluidised bed appeared to be high. The relative influence of the fluidising velocity (and the corresponding bed area), tube diameter, tube spacing, heat transfer coefficient and bed temperature on pumping power and overall cost was determined. This showed the importance of close tube packing and research was undertaken to see if this would adversely affect the heat transfer coefficient. Pressure operation also reduces the pumping power. Fouling and corrosion tests in beds burning coal suggest that higher temperatures could be reached reliably and cost studies show that, provided the better refractory metals are used, the cost of achieving higher temperatures is not unduly high. It now remains to demonstrate at large scale that the proposed systems are viable and that the methods incorporated to overcome start up and part lead running problems are satisfactory. The promising role of these heat transfer techniques in other applications is briefly discussed

  12. Attraction of stink bug (Hemiptera: Pentatomidae) nymphs to Euschistus aggregation pheromone in the field

    Science.gov (United States)

    Phytophagous stink bugs (Hemiptera: Pentatomidae) are primary pests in most fruit, vegetable, grain, and row crops worldwide. Pheromones have been identified and synthesized for several species of economically important stink bug pests. When yellow pyramid traps are baited with lures containing thes...

  13. Adjacent habitat influence on stink bug (Hemiptera: Pentatomidae) densities and the associated damage at field corn and soybean edges.

    Science.gov (United States)

    Venugopal, P Dilip; Coffey, Peter L; Dively, Galen P; Lamp, William O

    2014-01-01

    The local dispersal of polyphagous, mobile insects within agricultural systems impacts pest management. In the mid-Atlantic region of the United States, stink bugs, especially the invasive Halyomorpha halys (Stål 1855), contribute to economic losses across a range of cropping systems. Here, we characterized the density of stink bugs along the field edges of field corn and soybean at different study sites. Specifically, we examined the influence of adjacent managed and natural habitats on the density of stink bugs in corn and soybean fields at different distances along transects from the field edge. We also quantified damage to corn grain, and to soybean pods and seeds, and measured yield in relation to the observed stink bug densities at different distances from field edge. Highest density of stink bugs was limited to the edge of both corn and soybean fields. Fields adjacent to wooded, crop and building habitats harbored higher densities of stink bugs than those adjacent to open habitats. Damage to corn kernels and to soybean pods and seeds increased with stink bug density in plots and was highest at the field edges. Stink bug density was also negatively associated with yield per plant in soybean. The spatial pattern of stink bugs in both corn and soybeans, with significant edge effects, suggests the use of pest management strategies for crop placement in the landscape, as well as spatially targeted pest suppression within fields.

  14. Adjacent habitat influence on stink bug (Hemiptera: Pentatomidae densities and the associated damage at field corn and soybean edges.

    Directory of Open Access Journals (Sweden)

    P Dilip Venugopal

    Full Text Available The local dispersal of polyphagous, mobile insects within agricultural systems impacts pest management. In the mid-Atlantic region of the United States, stink bugs, especially the invasive Halyomorpha halys (Stål 1855, contribute to economic losses across a range of cropping systems. Here, we characterized the density of stink bugs along the field edges of field corn and soybean at different study sites. Specifically, we examined the influence of adjacent managed and natural habitats on the density of stink bugs in corn and soybean fields at different distances along transects from the field edge. We also quantified damage to corn grain, and to soybean pods and seeds, and measured yield in relation to the observed stink bug densities at different distances from field edge. Highest density of stink bugs was limited to the edge of both corn and soybean fields. Fields adjacent to wooded, crop and building habitats harbored higher densities of stink bugs than those adjacent to open habitats. Damage to corn kernels and to soybean pods and seeds increased with stink bug density in plots and was highest at the field edges. Stink bug density was also negatively associated with yield per plant in soybean. The spatial pattern of stink bugs in both corn and soybeans, with significant edge effects, suggests the use of pest management strategies for crop placement in the landscape, as well as spatially targeted pest suppression within fields.

  15. Bug-in-Ear eCoaching: Impacts on Novice Early Childhood Special Education Teachers

    Science.gov (United States)

    Grygas Coogle, Christan; Ottley, Jennifer R.; Rahn, Naomi L.; Storie, Sloan

    2018-01-01

    A multiple-probe, single-case design was used to determine the effects of bug-in-ear eCoaching on teachers' use of two targeted naturalistic communication strategies and focus children's responses to these strategies. Results indicated that bug-in-ear eCoaching enhanced teachers' use of communication strategies and the appropriate responses of…

  16. The characteristics of bed agglomeration during fluidized bed combustion of eucalyptus bark

    International Nuclear Information System (INIS)

    Chaivatamaset, Pawin; Tia, Suvit

    2015-01-01

    The bed agglomeration behaviors were investigated experimentally when eucalyptus bark was burning tested in a laboratory scale fluidized bed reactor. The focuses of this work were the influences of operating conditions and bed materials on the bed agglomeration tendency and the elucidation in the behaviors of fuel inorganic elements and the governing mode of the agglomeration. It was found that the defluidization caused by the bed agglomeration was clearly detectable from the decrease in measured bed pressure. The growth of bed particle and accumulation of agglomerates during combustion provided the partial to complete defluidization. The defluidization was promoted by the increase of bed temperature and bed particle size, and the decrease of fluidizing air velocity. The SEM-EDS analyses revealed that the bed agglomeration was mainly attributed to the formation of potassium silicate compounds as liquid phase during the combustion. This was initiated by the chemical reaction between the bed particle and the released ash constituents. In this study, the inorganic migration from fuel particle to bed particle was likely dominated by the condensation/reaction. The thermodynamic examination by ternary phase diagram analysis corroborated that the liquid phase formation of the ash derived materials controlled the agglomeration. The alumina sand prevented the bed agglomeration since it was inactive in the formation of viscous molten substances during combustion at the observed temperatures. - Highlights: • The behaviors of bed agglomeration were studied during the fluidized bed combustion of eucalyptus bark. • The increase in bed temperature and sand size, and the decrease of air velocity promoted bed defluidization. • The formation of molten potassium silicate compounds conduced to the bed agglomeration. • Condensation/reaction was the dominant inorganic migration mechanism from fuel particle to bed particle. • The alumina sand prevented effectively the bed

  17. Milkweed, stink bugs, and Georgia cotton

    Science.gov (United States)

    In peanut-cotton farmscapes in Georgia, stink bugs, i.e., Nezara viridula (L.)(Say) and Chinavia hilaris (Say), develop in peanut and then disperse at the crop-to-crop interface to feed on fruit in cotton. The main objective of this study was to examine the influence of a habitat of tropical milkwe...

  18. Bug breakfast in the bulletin: human papilloma virus.

    Science.gov (United States)

    Wallace, Cate; Weisberg, Edith; McCaffery, Kirsten

    2007-01-01

    The Bug Breakfast topic for October was Human Papilloma Virus (HPV). The presenters covered the epidemiology of HPV, the newly introduced HPV vaccine and social and psychological issues relating to HPV vaccination.

  19. Verde plant bug is associated with cottong boll rot in South Texas cotton

    Science.gov (United States)

    Verde plant bug was the dominant boll-feeding sucking bug species (>98% of insects collected using a beat bucket) from peak to late bloom in cotton fields near the coast along the Coastal Bend of South Texas, from Port Lavaca to the Lower Rio qrande Valley in 2010 and 2011. It was common in fields w...

  20. Quasi-two-layer morphodynamic model for bedload-dominated problems: bed slope-induced morphological diffusion.

    Science.gov (United States)

    Maldonado, Sergio; Borthwick, Alistair G L

    2018-02-01

    We derive a two-layer depth-averaged model of sediment transport and morphological evolution for application to bedload-dominated problems. The near-bed transport region is represented by the lower (bedload) layer which has an arbitrarily constant, vanishing thickness (of approx. 10 times the sediment particle diameter), and whose average sediment concentration is free to vary. Sediment is allowed to enter the upper layer, and hence the total load may also be simulated, provided that concentrations of suspended sediment remain low. The model conforms with established theories of bedload, and is validated satisfactorily against empirical expressions for sediment transport rates and the morphodynamic experiment of a migrating mining pit by Lee et al. (1993 J. Hydraul. Eng. 119 , 64-80 (doi:10.1061/(ASCE)0733-9429(1993)119:1(64))). Investigation into the effect of a local bed gradient on bedload leads to derivation of an analytical, physically meaningful expression for morphological diffusion induced by a non-zero local bed slope. Incorporation of the proposed morphological diffusion into a conventional morphodynamic model (defined as a coupling between the shallow water equations, Exner equation and an empirical formula for bedload) improves model predictions when applied to the evolution of a mining pit, without the need either to resort to special numerical treatment of the equations or to use additional tuning parameters.

  1. Quasi-two-layer morphodynamic model for bedload-dominated problems: bed slope-induced morphological diffusion

    Science.gov (United States)

    Maldonado, Sergio; Borthwick, Alistair G. L.

    2018-02-01

    We derive a two-layer depth-averaged model of sediment transport and morphological evolution for application to bedload-dominated problems. The near-bed transport region is represented by the lower (bedload) layer which has an arbitrarily constant, vanishing thickness (of approx. 10 times the sediment particle diameter), and whose average sediment concentration is free to vary. Sediment is allowed to enter the upper layer, and hence the total load may also be simulated, provided that concentrations of suspended sediment remain low. The model conforms with established theories of bedload, and is validated satisfactorily against empirical expressions for sediment transport rates and the morphodynamic experiment of a migrating mining pit by Lee et al. (1993 J. Hydraul. Eng. 119, 64-80 (doi:10.1061/(ASCE)0733-9429(1993)119:1(64))). Investigation into the effect of a local bed gradient on bedload leads to derivation of an analytical, physically meaningful expression for morphological diffusion induced by a non-zero local bed slope. Incorporation of the proposed morphological diffusion into a conventional morphodynamic model (defined as a coupling between the shallow water equations, Exner equation and an empirical formula for bedload) improves model predictions when applied to the evolution of a mining pit, without the need either to resort to special numerical treatment of the equations or to use additional tuning parameters.

  2. Bayesian Analysis for Penalized Spline Regression Using WinBUGS

    Directory of Open Access Journals (Sweden)

    Ciprian M. Crainiceanu

    2005-09-01

    Full Text Available Penalized splines can be viewed as BLUPs in a mixed model framework, which allows the use of mixed model software for smoothing. Thus, software originally developed for Bayesian analysis of mixed models can be used for penalized spline regression. Bayesian inference for nonparametric models enjoys the flexibility of nonparametric models and the exact inference provided by the Bayesian inferential machinery. This paper provides a simple, yet comprehensive, set of programs for the implementation of nonparametric Bayesian analysis in WinBUGS. Good mixing properties of the MCMC chains are obtained by using low-rank thin-plate splines, while simulation times per iteration are reduced employing WinBUGS specific computational tricks.

  3. MENGGALI METRIK YANG PENTING DALAM RANGKAIAN AKTIVITAS PERUBAHAN PERANGKAT LUNAK UNTUK MEMPREDIKSI BUG DENGAN ATURAN ASOSIASI

    Directory of Open Access Journals (Sweden)

    Achmad Arwan

    2014-01-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Dalam evolusi perangkat lunak terdapat rangkaian aktivitas proses perubahan yang kemudian oleh Nachiapan diformulasikan menjadi metrik-metrik yang mampu memprediksi bug secara presisi. Akan tetapi secara spesifik belum ditemukan seberapa besar pengaruh masing-masing metrik tersebut terhadap hasil prediksi sebuah bug. Penelitian ini mengusulkan pengukuran jumlah kemunculan metrik dengan kemunculan bug pada proyek eclipse. Sehingga dengan penelitian ini dapat diketahui metrik -metrik mana yang penting dalam prediksi kemunculan bug. Aturan asosiasi dalam penggalian data telah dipergunakan secara luas untuk menggali variabel-variabel saling terkait dalam sampel data. Metrik-metrik dalam proyek eclipse kemudian digali dengan aturan asosiasi untuk mendapatkan metrik yang muncul bersama bug. Hasil pengujian menunjukkan bahwa metrik Numberofchangeslate rata-rata kemunculannya sebesar 46,9%, sedangkan metrik Peopletotal muncul bersama bug rata-rata sebesar 43,57% dan metrik Numberofchangesearly memiliki kemunculan rata-rata 14% sehingga ketiga metrik tersebut merupakan metrik yang penting dalam memprediksi bug.

  4. Edge effects of stink bugs in corn, cotton, peanut and soybean fields adjacent to woodland.

    Science.gov (United States)

    Producers face significant crop losses from stink bug species in the southeastern USA, but the high mobility and polyphagy of the bugs make predictions of their presence in crops difficult. While there is some evidence that they colonize crops from adjacent crops, there are no studies of their colo...

  5. Economic Injury Level of the Neotropical Brown Stink Bug Euschistus heros (F.) on Cotton Plants.

    Science.gov (United States)

    Soria, M F; Degrande, P E; Panizzi, A R; Toews, M D

    2017-06-01

    In Brazil, the Neotropical brown stink bug, Euschistus heros (F.) (Hemiptera: Pentatomidae), commonly disperses from soybeans to cotton fields. The establishment of an economic treatment threshold for this pest on cotton crops is required. Infestation levels of adults of E. heros were evaluated on cotton plants at preflowering, early flowering, boll filling, and full maturity by assessing external and internal symptoms of injury on bolls, seed cotton/lint production, and fiber quality parameters. A completely randomized experiment was designed to infest cotton plants in a greenhouse with 0, 2, 4, 6, and 8 bugs/plant, except at the full-maturity stage in which only infestation with 8 bugs/plant and uninfested plants were evaluated. Results indicated that the preflowering, early-flowering, and full-maturity stages were not affected by E. heros. A linear regression model showed a significant increase in the number of internal punctures and warts in the boll-filling stage as the population of bugs increased. The average number of loci with mottled immature fibers was significantly higher at 4, 6, and 8 bugs compared with uninfested plants with data following a quadratic regression model. The seed and lint cotton was reduced by 18 and 25% at the maximum level of infestation (ca. 8 bugs/plant) in the boll-filling stage. The micronaire and yellowing indexes were, respectively, reduced and increased with the increase of the infestation levels. The economic injury level of E. heros on cotton plants at the boll-filling stage was determined as 0.5 adult/plant. Based on that, a treatment threshold of 0.1 adult/plant can be recommended to avoid economic losses.

  6. Bedbugs in Schools? Halting a Possible Epidemic

    Science.gov (United States)

    Waldorf, Glenn

    2012-01-01

    Bedbugs are a growing problem in schools today. Bedbugs are often confused with other insects, and their signs are hard to recognize. School officials should work with an experienced pest control company to confirm whether the insects are bed bugs and, if they are not, to identify them so they can be treated effectively. Education and vigilance…

  7. Verde plant bug, Creontiades signatus (Hemiptera: Miridae) effects of insect density and bloom period of infestation on cotton damage and yield

    Science.gov (United States)

    The verde plant bug, Creontiades signatus Distant (Hemiptera: Miridae), has emerged as a threat to cotton in South Texas, causing boll damage similar to boll-feeding stink bugs (Hemiptera: Pentatomidae). Verde plant bugs were released into caged cotton for a one-week period to characterize the effec...

  8. BIOLOGICAL FEATURES OF TARAN (RUTILUS HECKELII OF THE DNIEPER-BUG ESTUARY SYSTEM

    Directory of Open Access Journals (Sweden)

    K. Geina

    2016-03-01

    Full Text Available Purpose. To analyze morphological variability and basic biological features of the modern stock of taran of the Dnieper-Bug estuary system in the conditions of the transformed Dnieper flow. Methodology. Morphological variability was determined based on the comparison of morphological features of roach Rutilus rutilus (Linnaeus, 1758 of the Kakhovka reservoir and semi-migratory taran Rutilus rutilus heckelii (Nordmann, 1840 of the Dnieper-Bug estuary system. As a main criterion of the evaluation of the taran stock biological state, we used age, sex structure, growth characteristics, fecundity and condition factor. Fish sampling was carried out at stationary monitoring-observation stations of the Institute of Fisheries NAAS of Ukraine. Field and cameral processing of the collected materials were performed based on conventional methods and guidelines. Findings. Morphological variability analysis demonstrated significant differences between Dnieper and Bug taran. The highest differences were observed for antroventral distance (td=11.19. Significant differences were also observed for antenanal and ventroanal distances td=4.05-4.14. No significant differences were found for meristic features. There were also significant differences between Dnieper-Bug taran and Kakhovka reservoir roach, which had formed a resident form after regulating the Dnieper River flow. Kakhovka reservoir roach is more deep-bodied with Н=32.79%, t-test value was 5.65. Pelvic fins were more shifted to the caudal fin (td=5.28 that resulted in significant difference (p<0.05 in ventroanal distance (td=4.26. Taran also had somewhat smaller length of the anal fin base (td=4.73 but its height was higher – td=5.78. The main peculiarity of the current biological state of taran stock is the domination of young age groups. The small number of fish in the boundary groups of the age series right wing with relative stability of growth features indicate on intensive pressure on the

  9. Bug bites and stings: When to see a dermatologist

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  10. Bug bites and stings: When to see a dermatologist

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    Full Text Available ... aging skin care Kids’ zone About skin: Your body's largest organ About hair: Not just on your ... bug bite, such as a rash, fever, or body aches, see your doctor or a board-certified ...

  11. Bug bites and stings: When to see a dermatologist

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    Full Text Available ... bites Although most bug bites are harmless, some can spread dangerous diseases like Zika virus, dengue, Lyme ... and tuck your shirt into your pants. You can also pre-treat outer layers of clothing with ...

  12. Bug bites and stings: When to see a dermatologist

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    Full Text Available ... a dermatologist Why see a board-certified dermatologist? Home Public and patients Skin, hair, and nail care ... bites and stings can be safely treated at home. To treat bug bites and stings at home, ...

  13. Biology, Pest Status, Microbiome and Control of Kudzu Bug (Hemiptera: Heteroptera: Plataspidae): A New Invasive Pest in the U.S.

    Science.gov (United States)

    Dhammi, Anirudh; van Krestchmar, Jaap B.; Ponnusamy, Loganathan; Bacheler, Jack S.; Reisig, Dominic D.; Herbert, Ames; Del Pozo-Valdivia, Alejandro I.; Roe, R. Michael

    2016-01-01

    Soybean is an important food crop, and insect integrated pest management (IPM) is critical to the sustainability of this production system. In recent years, the introduction into the United States of the kudzu bug currently identified as Megacopta cribraria (F.), poses a threat to soybean production. The kudzu bug was first discovered in the state of Georgia, U.S. in 2009 and since then has spread to most of the southeastern states. Because it was not found in the North American subcontinent before this time, much of our knowledge of this insect comes from research done in its native habitat. However, since the U.S. introduction, studies have been undertaken to improve our understanding of the kudzu bug basic biology, microbiome, migration patterns, host selection and management in its expanding new range. Researchers are not only looking at developing IPM strategies for the kudzu bug in soybean, but also at its unique relationship with symbiotic bacteria. Adult females deposit bacterial packets with their eggs, and the neonates feed on these packets to acquire the bacteria, Candidatus Ishikawaella capsulata. The kudzu bug should be an informative model to study the co-evolution of insect function and behavior with that of a single bacteria species. We review kudzu bug trapping and survey methods, the development of bioassays for insecticide susceptibility, insecticide efficacy, host preferences, impact of the pest on urban environments, population expansion, and the occurrence of natural enemies. The identity of the kudzu bug in the U.S. is not clear. We propose that the kudzu bug currently accepted as M. cribraria in the U.S. is actually Megacopta punctatissima, with more work needed to confirm this hypothesis. PMID:27649166

  14. Bug bites and stings: When to see a dermatologist

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    Full Text Available ... Particularly if you’re visiting areas with known insect-borne diseases, it’s important to take steps to ... bug bites, dermatologists recommend the following tips: Use insect repellent. To protect against mosquitoes, ticks and other ...

  15. Bug bites and stings: When to see a dermatologist

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    Full Text Available ... Choosing Wisely Education Online Learning Center MOC Recognized Credit Basic Derm Curriculum Teaching and learning guides Suggested ... it’s important to take steps to reduce your risk. To help prevent bug bites, dermatologists recommend the ...

  16. Bug bites and stings: When to see a dermatologist

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    Full Text Available ... and Lectureship Clarence S. Livingood Award and Lectureship Marion B. Sulzberger Award and Lectureship Master Dermatologist Award Members ... skin Bug bites and stings "); (function () { var a = "", b = [ "adid=aad-aad-1", "site=ehs.con.aad. ...

  17. Recolonization of bat roost by bat bugs (Cimex pipistrelli): could parasite load be a cause of bat roost switching?

    Science.gov (United States)

    Bartonička, Tomáš; Růžičková, Lucie

    2013-04-01

    Roost ectoparasites are believed to have a negative impact on fitness of their hosts as birds or mammals. Previous studies were mostly focussed on the synchronization between reproduction cycles of ectoparasites and hosts living in infested roosts. However, to date, it has not been examined how fast ectoparasites colonize new, non-infested roosts and thus increasing the impact on the local populations of hosts. The parasite-host model was studied, including bat bugs Cimex pipistrelli and soprano pipistrelles Pipistrellus pygmaeus, where bat behaviour was observed which tended to reduce the parasite load in bat roosts. We investigated (1) whether bats change their roosting behaviour when we discontinued synchronization of their reproduction and the life cycle of the bat bugs and (2) how fast and which stages of bat bugs reoccupy cleaned roosts. In a 3-year field experiment, we removed all bat bugs from six bat boxes in each spring. Pipistrelles bred young in all non-infested boxes during these 3 years. In addition, 8 years of regular observations before this experiment indicate that bats avoided breeding in the same bat boxes at all. Bat bugs were found again in clean boxes in mid-May. However, their densities did not maximise before the beginning of June, before parturition. A re-appearance of bugs was observed after 21-56 days after the first bat visit. Adult bugs, mainly females, colonised cleaned boxes first though at the same time there were a lot of younger and smaller instars in non-manipulated roosts in the vicinity.

  18. Big-Eyed Bugs Have Big Appetite for Pests

    Science.gov (United States)

    Many kinds of arthropod natural enemies (predators and parasitoids) inhabit crop fields in Arizona and can have a large negative impact on several pest insect species that also infest these crops. Geocoris spp., commonly known as big-eyed bugs, are among the most abundant insect predators in field c...

  19. Bug bites and stings: When to see a dermatologist

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    Full Text Available ... hair, and nail care Skin care Hair care / hair loss Injured skin Nail care Anti-aging skin care ... hair, and nail care Skin care Hair care / hair loss Injured skin Blisters Bug bites and stings How ...

  20. Bug bites and stings: When to see a dermatologist

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  1. Code development for debris bed coolability problem. Final report for the period 1997-05-01 - 1999-08-14

    International Nuclear Information System (INIS)

    Loboiko, A.I.

    2000-03-01

    The study was devoted to the problem of debris bed coolability arising from severe accident at nuclear power reactor. After reactor core melting occurs and subsequent debris bed is formed in the lower plenum of reactor pressure vessel (RPV) it is important to confine this debris bed inside RPV boundary. One of the possible accident scenarios assumes the interaction between coolant and molten core materials resulting from rapid melt quenching, freezing and fragmentation. Particulated fuel and steel may subsequently settle on available surfaces within the reactor vessel, forming debris porous beds which produce radioactive decay heating. In case of severe core degradation, such heat transfer mechanisms as radiation, conduction and natural single-phase convection may appear to be insufficient and coolant boiling may happen on the surface or inside the bed. Depending on rate of heat generation there may be sufficient debris cool down or its 'dryout' which pose a danger for RPV integrity. The study considers development of 2D numerical code capable to predict coolant saturation as a function of different parameters. Analysis of previous activities on one-dimensional and multi-dimensional models was done. On the basis of the analysis it was concluded that the correct prediction of the debris saturation on dryant power requires two-dimensional numerical simulation considering the processes like two-phase convection, capillary effects, different models of permeability, different models of heat transfer between solid debris and coolant, non-homogeneity of parameters porous medium, heat and mass transfer between debris bed and a highly porous gap along the inner RPV surface. Particular attention was given to consideration of boundary conditions for debris bed. Introduction of the analytical model for dependence of gap properties on heat flux from debris bed allowed to create an algorithm for use in numerical calculations and finally to develop a code which allowed for stable

  2. A Transcriptome Survey Spanning Life Stages and Sexes of the Harlequin Bug, Murgantia histrionica

    Directory of Open Access Journals (Sweden)

    Michael E. Sparks

    2017-05-01

    Full Text Available The harlequin bug, Murgantia histrionica (Hahn, is an agricultural pest in the continental United States, particularly in southern states. Reliable gene sequence data are especially useful to the development of species-specific, environmentally friendly molecular biopesticides and effective biolures for this insect. Here, mRNAs were sampled from whole insects at the 2nd and 4th nymphal instars, as well as sexed adults, and sequenced using Illumina RNA-Seq technology. A global assembly of these data identified 72,540 putative unique transcripts bearing high levels of similarity to transcripts identified in other taxa, with over 99% of conserved single-copy orthologs among insects being detected. Gene ontology and protein family analyses were conducted to explore the functional potential of the harlequin bug’s gene repertoire, and phylogenetic analyses were conducted on gene families germane to xenobiotic detoxification, including glutathione S-transferases, carboxylesterases and cytochrome P450s. Genic content in harlequin bug was compared with that of the closely related invasive pest, the brown marmorated stink bug, Halyomorpha halys (Stål. Quantitative analyses of harlequin bug gene expression levels, experimentally validated using quantitative real-time PCR, identified genes differentially expressed between life stages and/or sexes.

  3. Pheromone of the banana-spotting bug, amblypelta lutescens lutescens Distant (Hemiptera: Coreidae): identification, synthesis and field bioassay

    Science.gov (United States)

    The banana spotting bug Amblypelta lutescens lutescens Distant (Hemiptera: Coreidae) is one of the principal pests of tree fruits and nuts across northern and eastern Australia. Apart from damage assessments in orchards, there are currently no other methods for monitoring bug activity to aid manage...

  4. Environmental protection stability of river bed and banks using convex, concave, and linear bed sills.

    Science.gov (United States)

    Keshavarzi, Alireza; Noori, Lila Khaje

    2010-12-01

    River bed scourings are a major environmental problem for fish and aquatic habitat resources. In this study, to prevent river bed and banks from scouring, different types of bed sills including convex, concave and linear patterns were installed in a movable channel bed in a laboratory flume. The bed sills were tested with nine different arrangements and under different flow conditions. To find the most effective bed sill pattern, the scouring depth was measured downstream of the bed sill for a long experimental duration. The scour depth was measured at the middle and at the end of each experimental test for different ratios of the arch radius to the channel width [r/w]. The experimental results indicated that the convex pattern with r/w=0.35 produced minimum bed scouring depth at the center line whereas the concave pattern with r/w=0.23 produced the minimum scour depth at the wall banks. Therefore, the convex pattern was the most effective configuration for prevention of scouring at the center line of the river while the concave pattern was very effective to prevent scouring at the river banks. These findings can be suggested to be used in practical applications.

  5. 2016 All Bugs Good and Bad Webinar Series - eXtension

    Science.gov (United States)

    Importadas Resources Instructional Videos Publications Top of the Mound Game Fire Ant Images from BugMugs.org Breeding and Genomics Sheep Small and Backyard Flocks Small Meat Processors Sustainable Marine Fisheries

  6. Bug bites and stings: When to see a dermatologist

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    Full Text Available ... Mohs AUC MyDermPath+ Psoriasis Patient education resources Practice Management Center Coding and reimbursement Coding MACRA Fee schedule ... it’s important to take steps to reduce your risk. To help prevent bug bites, dermatologists recommend the ...

  7. Bug bites and stings: When to see a dermatologist

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    Full Text Available ... dress appropriately to prevent bug bites. Cover exposed skin as much as possible by wearing long-sleeved shirts, pants, socks and closed shoes instead of sandals. For additional protection, pull your socks up over your pants and ...

  8. Melt With This Kiss: Paralyzing and Liquefying Venom of The Assassin Bug Pristhesancus plagipennis (Hemiptera: Reduviidae).

    Science.gov (United States)

    Walker, Andrew A; Madio, Bruno; Jin, Jiayi; Undheim, Eivind A B; Fry, Bryan G; King, Glenn F

    2017-04-01

    Assassin bugs (Hemiptera: Heteroptera: Reduviidae) are venomous insects, most of which prey on invertebrates. Assassin bug venom has features in common with venoms from other animals, such as paralyzing and lethal activity when injected, and a molecular composition that includes disulfide-rich peptide neurotoxins. Uniquely, this venom also has strong liquefying activity that has been hypothesized to facilitate feeding through the narrow channel of the proboscis-a structure inherited from sap- and phloem-feeding phytophagous hemipterans and adapted during the evolution of Heteroptera into a fang and feeding structure. However, further understanding of the function of assassin bug venom is impeded by the lack of proteomic studies detailing its molecular composition.By using a combined transcriptomic/proteomic approach, we show that the venom proteome of the harpactorine assassin bug Pristhesancus plagipennis includes a complex suite of >100 proteins comprising disulfide-rich peptides, CUB domain proteins, cystatins, putative cytolytic toxins, triabin-like protein, odorant-binding protein, S1 proteases, catabolic enzymes, putative nutrient-binding proteins, plus eight families of proteins without homology to characterized proteins. S1 proteases, CUB domain proteins, putative cytolytic toxins, and other novel proteins in the 10-16-kDa mass range, were the most abundant venom components. Thus, in addition to putative neurotoxins, assassin bug venom includes a high proportion of enzymatic and cytolytic venom components likely to be well suited to tissue liquefaction. Our results also provide insight into the trophic switch to blood-feeding by the kissing bugs (Reduviidae: Triatominae). Although some protein families such as triabins occur in the venoms of both predaceous and blood-feeding reduviids, the composition of venoms produced by these two groups is revealed to differ markedly. These results provide insights into the venom evolution in the insect suborder

  9. Modelling the transition between fixed and mobile bed conditions in two-phase free-surface flows: The Composite Riemann Problem and its numerical solution

    Science.gov (United States)

    Rosatti, Giorgio; Zugliani, Daniel

    2015-03-01

    In a two-phase free-surface flow, the transition from a mobile-bed condition to a fixed-bed one (and vice versa) occurs at a sharp interface across which the relevant system of partial differential equations changes abruptly. This leads to the possibility of conceiving a new type of Riemann Problem (RP), which we have called Composite Riemann Problem (CRP), where not only the initial constant values of the variables but also the system of equations change from left to right of a discontinuity. In this paper, we present a strategy for solving a CRP by reducing it to a standard RP of a single, composite system of equations. This can be obtained by combining the two original systems by means of a suitable weighting function, namely the erodibility variable, and the introduction of an appropriate differential equation for this quantity. In this way, the CRP problem can be analyzed theoretically with standard methods, and the features of the solutions can be clearly identified. In particular, a stationary contact wave is able to correctly describe the sharp transition between mobile- and fixed-bed conditions. A finite volume scheme based on the Multiple Averages Generalized Roe approach (Rosatti and Begnudelli (2013) [22]) was used to numerically solve the fixed-mobile CRP. Several test cases demonstrate the effectiveness, exact well balanceness and high accuracy of the scheme when applied to problems that fall within the physical range of applicability of the relevant mathematical model.

  10. Computer games to teach hygiene: an evaluation of the e-Bug junior game.

    Science.gov (United States)

    Farrell, David; Kostkova, Patty; Weinberg, Julius; Lazareck, Lisa; Weerasinghe, Dasun; Lecky, Donna M; McNulty, Cliodna A M

    2011-06-01

    Handwashing, respiratory hygiene and antibiotic resistance remain major public health concerns. In order to facilitate an effective outcome when teaching the basic principles of hand and respiratory hygiene, educational interventions should first target school children. As computer games are ubiquitous in most children's lives, e-Bug developed computer games targeted at teaching children handwashing, respiratory hygiene and antibiotic resistance. The games were designed for two target audiences: junior school children (9-12 year olds); and senior school children (13-15 year olds). Between May and August 2009, the finalized junior game underwent an evaluation in three UK schools (in Glasgow, Gloucester and London), involving 62 children in the schools and ∼ 1700 players accessing the junior game online. The e-Bug junior game consists of a number of levels of play, each of which promotes a set of learning outcomes (LOs). These LOs, complementary to those in the e-Bug packs, are expressed through the game mechanics (the rules of the game) rather than through story or dialogue. Although the junior game's evaluation demonstrated a statistically significant change in the knowledge for only a small number of given LOs, because many children had the required knowledge already before playing the game, this is e-Bug's first statistical study on the junior game and the first comprehensive evaluation of its kind. Future work includes a re-examination of the quiz-style questionnaires utilized in this study and an exploration of the potential knowledge change acquired strictly through engagement.

  11. Single and multiple in-season measurements as indicators of at-harvest cotton boll damage caused by verde plant bug (Hemiptera: Miridae).

    Science.gov (United States)

    Brewer, Michael J; Armstrong, J Scott; Parker, Roy D

    2013-06-01

    The ability to monitor verde plant bug, Creontiades signatus Distant (Hemiptera: Miridae), and the progression of cotton, Gossypium hirsutum L., boll responses to feeding and associated cotton boll rot provided opportunity to assess if single in-season measurements had value in evaluating at-harvest damage to bolls and if multiple in-season measurements enhanced their combined use. One in-season verde plant bug density measurement, three in-season plant injury measurements, and two at-harvest damage measurements were taken in 15 cotton fields in South Texas, 2010. Linear regression selected two measurements as potentially useful indicators of at-harvest damage: verde plant bug density (adjusted r2 = 0.68; P = 0.0004) and internal boll injury of the carpel wall (adjusted r2 = 0.72; P = 0.004). Considering use of multiple measurements, a stepwise multiple regression of the four in-season measurements selected a univariate model (verde plant bug density) using a 0.15 selection criterion (adjusted r2 = 0.74; P = 0.0002) and a bivariate model (verde plant bug density-internal boll injury) using a 0.25 selection criterion (adjusted r2 = 0.76; P = 0.0007) as indicators of at-harvest damage. In a validation using cultivar and water regime treatments experiencing low verde plant bug pressure in 2011 and 2012, the bivariate model performed better than models using verde plant bug density or internal boll injury separately. Overall, verde plant bug damaging cotton bolls exemplified the benefits of using multiple in-season measurements in pest monitoring programs, under the challenging situation when at-harvest damage results from a sequence of plant responses initiated by in-season insect feeding.

  12. American Trypanosomiasis (Also Known as Chagas Disease) Triatomine Bug FAQs

    Science.gov (United States)

    ... are typically found in the southern United States, Mexico, Central America, and South America (as far south ... feed on the blood of mammals (including humans), birds, and reptiles. Triatomine bugs live in a wide ...

  13. Bugs, Planes, and Ferris Wheels: A Problem-Centered Curriculum

    Science.gov (United States)

    Campbell, William E.; Kemp, Joyce C.; Zia, Joan H.

    2006-01-01

    This article describes a problem-centered curriculum for grades 9-12, using problem sets developed by a mathematics department and designed to take the place of textbooks. The students discover mathematical concepts in the context of the problems and activities in the materials.

  14. Approximate solutions to the deep bed filtration problem; Solucoes aproximadas para o problema de deposicao profunda

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Julio M.; Marchesin, Dan [Instituto de Matematica Pura e Aplicada (IMPA), Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The deep bed filtration problem is closely related to secondary oil recovery. In this work we derive explicit solutions to two filtration problems. The filtration function varies non-linearly with the Darcy speed and linearly with the deposition, but very little. The first solution is built by the method of perturbations and although it is only an approximation it is available in multiple symmetries, including the radial geometry used in the field. The main motivation is the validation of numerical methods. The second solution is exact but it is only available in the linear symmetry, i.e., laboratory geometry. We use it to verify the accuracy of the first solution, but it can also be used to simulate the deposition in experiments. (author)

  15. Recovery strategies for fluxes affected by the Gill-Solent WindMaster-Pro "w-boost" firmware bug

    Science.gov (United States)

    Billesbach, D. P.; Chan, S. W.; Biraud, S.; David, C. R.

    2017-12-01

    In late 2015 and early 2016, work done by the AmeriFlux Tech Team helped to uncover a bug in the Gill WindMaster Pro sonic anemometers used by many researchers for eddy covariance flux measurements. Gill has addressed this issue and has since sent out a notice that the vertical wind speed component (a critical piece of all eddy covariance fluxes) was being erroneously computed and reported. The problem (known as the w-boost bug) resulted in positive (upward) wind speeds being under-reported by 16.6% and negative (downward) wind speeds being under-reported by 28.9%. This has the potential to cause similar underestimates in fluxes obtained from these instruments. While the manufacturer has offered a firmware upgrade to fix this bug, there exist many data sets that have already been affected by it. Researchers who use the affected units have contributed to numerous data archives (AmeriFlux, FluxNet, ICOS, etc.), and third-party scientists have, in turn used these data in many types of research projects. The volume of affected data over such a long period of time makes a complete reprocessing of the raw data sets impractical. To address this, the AmeriFlux Tech Team has endeavored to develop a method of correcting affected fluxes using only the downloadable data sets that are available from these archives. In a previous poster, we reported preliminary results from a pair of Arctic tundra flux towers, and showed that fluxes could be underestimated by 15% to 20%. In this poster, we present results that extend our study to include a forested site in Equatorial Africa. We also have evaluated methods to estimate flux errors without accessing the raw data sets.

  16. Virtual Reality Check: Teachers Use Bug-in-Ear Coaching to Practice Feedback Techniques with Student Avatars

    Science.gov (United States)

    Elford, Marti; Carter, Richard A., Jr.; Aronin, Sara

    2013-01-01

    There is not just one way to give feedback, nor is there just one kind of feedback. Bug-in-ear technology, which allows coaches to give teachers in the classroom immediate feedback, has been used successfully for 35 years. In an updated twist on this method, researchers at the University of Kansas used bug-in-ear coaching in a virtual classroom…

  17. Comparative susceptibilities of different life stages of the tarnished plant bug (Hemiptera: miridae) to three classes of insecticide

    Science.gov (United States)

    Insecticidal control of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is targeted at the adult and nymphal stages, but there is little information on relative susceptibilities of these insects to insecticides. Tarnished plant bug adults were collected from various locations in Mi...

  18. Seasonal and regional dynamics of M. ulcerans transmission in environmental context: deciphering the role of water bugs as hosts and vectors.

    Science.gov (United States)

    Marion, Estelle; Eyangoh, Sara; Yeramian, Edouard; Doannio, Julien; Landier, Jordi; Aubry, Jacques; Fontanet, Arnaud; Rogier, Christophe; Cassisa, Viviane; Cottin, Jane; Marot, Agnès; Eveillard, Matthieu; Kamdem, Yannick; Legras, Pierre; Deshayes, Caroline; Saint-André, Jean-Paul; Marsollier, Laurent

    2010-07-06

    Buruli ulcer, the third mycobacterial disease after tuberculosis and leprosy, is caused by the environmental mycobacterium M. ulcerans. Various modes of transmission have been suspected for this disease, with no general consensus acceptance for any of them up to now. Since laboratory models demonstrated the ability of water bugs to transmit M. ulcerans, a particular attention is focused on the transmission of the bacilli by water bugs as hosts and vectors. However, it is only through detailed knowledge of the biodiversity and ecology of water bugs that the importance of this mode of transmission can be fully assessed. It is the objective of the work here to decipher the role of water bugs in M. ulcerans ecology and transmission, based on large-scale field studies. The distribution of M. ulcerans-hosting water bugs was monitored on previously unprecedented time and space scales: a total of 7,407 water bugs, belonging to large number of different families, were collected over one year, in Buruli ulcer endemic and non endemic areas in central Cameroon. This study demonstrated the presence of M. ulcerans in insect saliva. In addition, the field results provided a full picture of the ecology of transmission in terms of biodiversity and detailed specification of seasonal and regional dynamics, with large temporal heterogeneity in the insect tissue colonization rate and detection of M. ulcerans only in water bug tissues collected in Buruli ulcer endemic areas. The large-scale detection of bacilli in saliva of biting water bugs gives enhanced weight to their role in M. ulcerans transmission. On practical grounds, beyond the ecological interest, the results concerning seasonal and regional dynamics can provide an efficient tool in the hands of sanitary authorities to monitor environmental risks associated with Buruli ulcer.

  19. Bug bites and stings: When to see a dermatologist

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    Full Text Available ... Private payer Medicare physician payment MACRA implementation Alternative payment models Fee schedule State policy State policy and action ... a dermatologist Why see a board-certified dermatologist? Home Public and patients Skin, hair, and nail care Injured skin Bug bites and stings "); (function () { var ...

  20. Biochemical Assay Detects Feeding Damage to Loblolly Pine Seeds Caused by the Leaffooted Pine Seed Bug (Hemiptera: Coreidae)

    Science.gov (United States)

    Cameron G. Lait; Daniel R. Miller; Sarah L. Bates; John H. Borden; Allison R. Kermode

    2003-01-01

    A large number of proteins in salivary gland extracts of the leaffooted pine seed bug, Leptoglossus corculus Say, were strongly recognized by a polyclonal antibody-based assay developed for detecting saliva of the western conifer seed bug, Lepfoglossus occidentalis Heidemann, in lodgepole pine, Pinus contorta var...

  1. The Bad Bugs Book Club: Science, Literacy, and Engagement

    Directory of Open Access Journals (Sweden)

    Joanna Verran

    2013-01-01

    Full Text Available The Bad Bugs Bookclub was launched in 2009. It comprises scientists and non-scientists. The aim of the Bookclub is to read and discuss novels where infectious disease forms part of the plot, in order to enhance learning about microbiology. The focus of the discussion is on appreciation of the novel, its scientific (microbiologic accuracy and relevance to contemporary microbiology. There are several potential audiences for the Bad Bugs Bookclub, for example students in a classroom setting, or in a more social environment, and/or the general public.  Meeting reports and reading guides have been posted on a dedicated website. For education purposes, additional project work for assessment is suggested for students reading each novel. Bookclub meetings may be held on particular dates in the microbiologic calendar, coupled with additional public engagement activities and student participation. The approach has significant flexibility in terms of intended audience, assessment and extension work, and provides a refreshing and stimulating alternative means for talking about microbiology.

  2. Verde plant bug associatioin with boll damage including cotton boll rot and potential in-season indicators of damage

    Science.gov (United States)

    Cotton along the Gulf Coast of south Texas has experienced loss from cotton boll rot especially during the last 10 to 15 years, and stink bugs and plant bugs (Hemiptera: Pentatomidae and Miridae) that feed on cotton bolls have been suspected in introducing the disease. A replicated grower field surv...

  3. Chemical Characterization of Bed Material Coatingsby LA-ICP-MS and SEM-EDS

    Science.gov (United States)

    Piispanen, M. H.; Mustonen, A. J.; Tiainen, M. S.; Laitinen, R. S.

    Bed material coatings and the consequent agglomeration of bed material are main ash-related problems in FB-boilers. The bed agglomeration is a particular problem when combusting biofuels and waste materials. Whereas SEM-EDS together with automated image processing has proven to be a convenient method to study compositional distribution in coating layers and agglomerates, it is a relatively expensive technique and is not necessarily widely available. In this contribution, we explore the suitability of LA-ICP-MS to provide analogous information of the bed.

  4. Potential health impacts of burning coal beds and waste banks

    Science.gov (United States)

    Finkelman, R.B.

    2004-01-01

    Uncontrolled release of pollutants from burning coal beds and waste banks presents potential environmental and human health hazards. On a global scale, the emissions of large volumes of greenhouse gases from burning coal beds may contribute to climate change that alters ecosystems and patterns of disease occurrence. On regional and local scales, the emissions from burning coal beds and waste banks of acidic gases, particulates, organic compounds, and trace elements can contribute to a range of respiratory and other human health problems. Although there are few published reports of health problems caused by these emissions, the potential for problems can be significant. In India, large numbers of people have been displaced from their homes because of health problems caused by emissions from burning coal beds. Volatile elements such as arsenic, fluorine, mercury, and selenium are commonly enriched in coal deposits. Burning coal beds can volatilize these elements, which then can be inhaled, or adsorbed on crops and foods, taken up by livestock or bioaccumulated in birds and fish. Some of these elements can condense on dust particles that can be inhaled or ingested. In addition, selenium, arsenic, lead, tin, bismuth, fluorine, and other elements condense where the hot gaseous emissions come in contact with ambient air, forming mats of concentrated efflorescent minerals on the surface of the ground. These mats can be leached by rainwater and washed into local water bodies providing other potential routes of exposure. Although there are little data linking burning coal beds and waste banks to known health problems, a possibly analogous situation exists in rural China where mineralized coal burned in a residential environment has caused widespread and severe health problems such as fluorosis and arseniasis. ?? 2004 Elsevier B.V. All rights reserved.

  5. Insecticide assays against the brown stink bug feeding on pecan

    Science.gov (United States)

    The brown stink bug, Euschistus servus (Say) (Hemiptera: Pentatomidae), is an economic pest of pecan, Carya illinoinensis (Wangenh) K. Koch (Juglandaceae), and other agronomic crops across the southeastern U.S. Management of this pest is mainly via insecticides. Many commercial products indicate o...

  6. Development of fluidized bed combustion of biomass; Leijupolttoprosessin kehittaeminen vaikeille biopolttoaineille soveltuvaksi

    Energy Technology Data Exchange (ETDEWEB)

    Hiltunen, M; Vaehaenen-Koivuluoma, T [Foster Wheeler Energia Oy, Karhula (Finland)

    1997-10-01

    Some commercial BFB boilers burning biofuels, or biofuels and industrial wood wastes have suffered serious problems in bed material sintering. In worst cases the cumulation of reactive alkali compounds has caused total sintering of bed material even during a few days` operation. This presentation reports the results obtained from three separate cases, where sintering problems occurred. Boiler A burned biofuel with quartz sand and limestone addition. Boiler B burned softwood bark and industrial wood waste with sand addition. Boiler C burned softwood bark and sludge with sand addition. Due to the fuel used, bed sintering occurred in all boilers. Obviously, sintering was also influenced by some technical problems. Bed material samples have been analyzed with XRF and SEM-EDS techniques. According to these analyses, the main reason for sintering in boiler A is the cumulation of reactive potassium in bed material. In boiler B, the main reason is the fuel change from a mixture of softwood bark and industrial wood waste to pure industrial wood waste. The extra load of reactive sodium exceeded the critical concentration of alkali compounds in bed material. Also in boiler C, the fuel change from a mixture of softwood bark and sludge to pure softwood bark seems to be one of the reasons for bed sintering. After the fuel change the bed saturated with reactive potassium and the bed sintered. (orig.)

  7. Respiratory function of the plastron in the aquatic bug Aphelocheirus aestivalis (Hemiptera, Aphelocheiridae).

    Science.gov (United States)

    Seymour, Roger S; Jones, Karl K; Hetz, Stefan K

    2015-09-01

    The river bug Aphelocheirus aestivalis is a 40 mg aquatic insect that, as an adult, relies totally on an incompressible physical gill to exchange respiratory gases with the water. The gill (called a 'plastron') consists of a stationary layer of air held in place on the body surface by millions of tiny hairs that support a permanent air-water interface, so that the insect never has to renew the gas at the water's surface. The volume of air in the plastron is extremely small (0.14 mm(3)), under slightly negative pressure and connected to the gas-filled tracheal system through spiracles on the cuticle. Here, we measure PO2 of the water and within the plastron gas with O2-sensing fibre optics to understand the effectiveness and limitations of the gas exchanger. The difference in PO2 is highest in stagnant water and decreases with increasing convection over the surface. Respiration of bugs in water-filled vials varies between 33 and 296 pmol O2 s(-1), depending on swimming activity. The effective thickness of the boundary layer around the plastron was calculated from respiration rate, PO2 difference and plastron surface area, according to the Fick diffusion equation and verified by direct measurements with the fibre-optic probes. In stagnant water, the boundary layer is approximately 500 μm thick, which nevertheless can satisfy the demands of resting bugs, even if the PO2 of the free water decreases to half that of air saturation. Active bugs require thinner boundary layers (∼ 100 μm), which are achieved by living in moving water or by swimming. © 2015. Published by The Company of Biologists Ltd.

  8. Statistical description of flume experiments on mixed-size bed-load transport and bed armoring processes

    Science.gov (United States)

    Chen, D.; Zhang, Y.

    2008-12-01

    The objective of this paper is to describe the statistical properties of experiments on non-uniform bed-load transport as well as the mechanism of bed armoring processes. Despite substantial effort made over the last two decades, the ability to compute the bed-load flux in a turbulent system remains poor. The major obstacles include the poor understanding of the formation of armor lays on bed surfaces. Such a layer is much flow-resistible than the underlying material and therefore significantly inhibits sediment transport from the reach. To study the problem, we conducted a flume study for mixed sand/gravel sediments. We observed that aggregated sediment blocks were the most common characters in armor layers - the largest sizes resist hydraulic forces, while the smaller sizes add interlocking support and prevent loss of fine material through gaps between the larger particles. Fractional transport rates with the existing of armor layers were measured with time by sediment trapping method at the end of flume. To address the intermittent and time-varying behavior of bed-load transport during bed armoring processes, we investigated the probability distribution of the fractional bed-load transport rates, and the underlying dynamic model derived from the continuous time random walk framework. Results indicate that it is critical to consider the impact of armor layers when a flow is sufficient to move some of the finer particles and yet insufficient to move all the larger particles on a channel bed.

  9. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... 0; c public SPOT Skin Cancer™ Diseases and treatments Skin, hair, and nail care Skin care Hair care / hair loss Injured skin Blisters Bug bites and stings How to remove a tick How to treat a bee sting When to see a dermatologist Burns Frostbite Splinters Treating sunburn Wound care Nail care ...

  10. Sea bed mapping and inspection

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The conference has 24 presentations on the topics: Sea bed mapping, inspection, positioning, hydrography, marine archaeology, remote operation vehicles and computerized simulation technologies, oil field activities and plans, technological experiences and problems. (tk)

  11. Insecticide susceptibility of Nezara viridula (Heteroptera: Pentatomidae) and three other stink bug species composing a soybean pest complex in Japan.

    Science.gov (United States)

    Takeuchi, Hiroaki; Endo, Nobuyuki

    2012-06-01

    The susceptibility of the stink bug species Nezara viridula (L.), Nezara antennata Scott, Piezodorus hybneri (Gmelin), and Riptortus pedestris (F.) to insecticides was tested, establishing their 50% lethal dose (LD50) values as baseline data. Third instars and adults of the four species were treated by topical application with seven insecticides: fenitrothion, fenthion, etofenprox, silafluofen, dinotefuran, clothianidin, and ethiprole. The weight of the stink bug and weight of the insecticide applied to each bug were used as explanatory variables in the probit regression analysis. The effect of the body weight on the dose-response relationship, the proportional model, was not uniform among the tested insecticide-stink bug combinations. However, the basic model fit all combinations and could estimate LD50 values successfully. Therefore, LD50 values at the medium (average) weight estimated by the basic model were selected to describe the susceptibility of the stink bugs. The LD50 value of silafluofen for N. viridula adults, and that of silafluofen and etofenprox for N. antennata adults, was at least 2,338 ng greater than the other species exposed to each insecticide. Almost all of the LD50 values for adults were over 10 times greater than those of the same species' nymphs treated with the same insecticide. Thus monitoring of occurring species and their developmental stages is important for controlling effectively the stink bug pest complex by insecticides, especially by silafluofen or etofenprox. The estimated LD50 values can be used as baseline data to compare the susceptibility of the species collected in another year or location.

  12. Bug22p, a conserved centrosomal/ciliary protein also present in higher plants, is required for an effective ciliary stroke in Paramecium.

    Science.gov (United States)

    Laligné, C; Klotz, C; de Loubresse, N Garreau; Lemullois, M; Hori, M; Laurent, F X; Papon, J F; Louis, B; Cohen, J; Koll, F

    2010-04-01

    Centrioles, cilia, and flagella are ancestral conserved organelles of eukaryotic cells. Among the proteins identified in the proteomics of ciliary proteins in Paramecium, we focus here on a protein, Bug22p, previously detected by cilia and basal-body high-throughput studies but never analyzed per se. Remarkably, this protein is also present in plants, which lack centrioles and cilia. Bug22p sequence alignments revealed consensus positions that distinguish species with centrioles/cilia from plants. In Paramecium, antibody and green fluorescent protein (GFP) fusion labeling localized Bug22p in basal bodies and cilia, and electron microscopy immunolabeling refined the localization to the terminal plate of the basal bodies, the transition zone, and spots along the axoneme, preferentially between the membrane and the microtubules. RNA interference (RNAi) depletion of Bug22p provoked a strong decrease in swimming speed, followed by cell death after a few days. High-speed video microscopy and morphological analysis of Bug22p-depleted cells showed that the protein plays an important role in the efficiency of ciliary movement by participating in the stroke shape and rigidity of cilia. The defects in cell swimming and growth provoked by RNAi can be complemented by expression of human Bug22p. This is the first reported case of complementation by a human gene in a ciliate.

  13. Characterization and Comparative Analysis of Olfactory Receptor Co-Receptor Orco Orthologs Among Five Mirid Bug Species

    Directory of Open Access Journals (Sweden)

    Qi Wang

    2018-03-01

    Full Text Available The phytophagous mirid bugs of Apolygus lucorum, Lygus pratensis as well as three Adelphocoris spp., including Adelphocoris lineolatus, A. suturalis, and A. fasciaticollis are major pests of multiple agricultural crops in China, which have distinct geographical distribution and occurrence ranges. Like many insect species, these bugs heavily rely on olfactory cues to search preferred host plants, thereby investigation on functional co-evolution and divergence of olfactory genes seems to be necessary and is of great interest. In the odorant detection pathway, olfactory receptor co-receptor (Orco plays critical role in the perception of odors. In this study, we identified the full-length cDNA sequences encoding three putative Orcos (AsutOrco, AfasOrco, and LpraOrco in bug species of A. suturalis, A. fasciaticollis, and L. pratensis based on homology cloning method. Next, sequence alignment, membrane topology and gene structure analysis showed that these three Orco orthologs together with previously reported AlinOrco and AlucOrco shared high amino acid identities and similar topology structure, but had different gene structure especially at the length and insertion sites of introns. Furthermore, the evolutional estimation on the ratios of non-synonymous to synonymous (Ka/Ks revealed that Orco genes were under strong purifying selection, but the degrees of variation were significant different between genera. The results of quantitative real-time PCR experiments showed that these five Orco genes had a similar antennae-biased tissue expression pattern. Taking these data together, it is thought that Orco genes in the mirid species could share conserved olfaction roles but had different evolution rates. These findings would lay a foundation to further investigate the molecular mechanisms of evolutionary interactions between mirid bugs and their host plants, which might in turn contribute to the development of pest management strategy for mirid bugs.

  14. Expanded-bed chromatography in primary protein purification.

    Science.gov (United States)

    Anspach, F B; Curbelo, D; Hartmann, R; Garke, G; Deckwer, W D

    1999-12-31

    Chromatography in stable expanded beds enables proteins to be recovered directly from cultivations of microorganisms or cells and preparations of disrupted cells, without the need for prior removal of suspended solids. The general performance of an expanded bed is comparable to a packed bed owing to reduced mixing of the adsorbent particles in the column. However, optimal operating conditions are more restricted than in a packed bed due to the dependence of bed expansion on the size and density of the adsorbent particles as well as the viscosity and density of the feedstock. The feedstock composition may become the most limiting restriction owing to interactions of adsorbent particles with cell surfaces, DNA and other substances, leading to their aggregation and consequently to bed instabilities and channeling. Despite these difficulties, expanded-bed chromatography has found widespread applications in the large scale purification of proteins from mammalian cell and microbial feedstocks in industrial bioprocessing. The basics and implementation of expanded-bed chromatography, its advantages as well as problems encountered in the use of this technique for the direct extraction of proteins from unclarified feedstocks are addressed.

  15. Sediment transport primer: estimating bed-material transport in gravel-bed rivers

    Science.gov (United States)

    Peter Wilcock; John Pitlick; Yantao Cui

    2009-01-01

    This primer accompanies the release of BAGS, software developed to calculate sediment transport rate in gravel-bed rivers. BAGS and other programs facilitate calculation and can reduce some errors, but cannot ensure that calculations are accurate or relevant. This primer was written to help the software user define relevant and tractable problems, select appropriate...

  16. Aflatoxin Contamination Detected in Nutrient and Anti-Oxidant Rich Edible Stink Bug Stored in Recycled Grain Containers.

    Directory of Open Access Journals (Sweden)

    Robert Musundire

    Full Text Available Recently, there has been multi-agency promotion of entomophagy as an environmentally-friendly source of food for the ever increasing human population especially in the developing countries. However, food quality and safety concerns must first be addressed in this context. We addressed these concerns in the present study using the edible stink bug Encosternum delegorguei, which is widely consumed in southern Africa. We analysed for mycotoxins, and health beneficials including antioxidants, amino acids and essential fatty acids using liquid chromatography coupled to quadrupole time of flight mass spectrometry (LC-Qtof-MS and coupled gas chromatography (GC-MS. We also performed proximate analysis to determine nutritional components. We identified the human carcinogen mycotoxin (aflatoxin B1 at low levels in edible stink bugs that were stored in traditonally woven wooden dung smeared baskets and gunny bags previously used to store cereals. However, it was absent in insects stored in clean zip lock bags. On the other hand, we identified 10 fatty acids, of which 7 are considered essential fatty acids for human nutrition and health; 4 flavonoids and 12 amino acids of which two are considered the most limiting amino acids in cereal based diets. The edible stink bug also contained high crude protein and fats but was a poor source of minerals, except for phosphorus which was found in relatively high levels. Our results show that the edible stink bug is a nutrient- and antioxidant-rich source of food and health benefits for human consumption. As such, use of better handling and storage methods can help eliminate contamination of the edible stink bug with the carcinogen aflatoxin and ensure its safety as human food.

  17. Aflatoxin Contamination Detected in Nutrient and Anti-Oxidant Rich Edible Stink Bug Stored in Recycled Grain Containers.

    Science.gov (United States)

    Musundire, Robert; Osuga, Isaac M; Cheseto, Xavier; Irungu, Janet; Torto, Baldwyn

    2016-01-01

    Recently, there has been multi-agency promotion of entomophagy as an environmentally-friendly source of food for the ever increasing human population especially in the developing countries. However, food quality and safety concerns must first be addressed in this context. We addressed these concerns in the present study using the edible stink bug Encosternum delegorguei, which is widely consumed in southern Africa. We analysed for mycotoxins, and health beneficials including antioxidants, amino acids and essential fatty acids using liquid chromatography coupled to quadrupole time of flight mass spectrometry (LC-Qtof-MS) and coupled gas chromatography (GC)-MS. We also performed proximate analysis to determine nutritional components. We identified the human carcinogen mycotoxin (aflatoxin B1) at low levels in edible stink bugs that were stored in traditonally woven wooden dung smeared baskets and gunny bags previously used to store cereals. However, it was absent in insects stored in clean zip lock bags. On the other hand, we identified 10 fatty acids, of which 7 are considered essential fatty acids for human nutrition and health; 4 flavonoids and 12 amino acids of which two are considered the most limiting amino acids in cereal based diets. The edible stink bug also contained high crude protein and fats but was a poor source of minerals, except for phosphorus which was found in relatively high levels. Our results show that the edible stink bug is a nutrient- and antioxidant-rich source of food and health benefits for human consumption. As such, use of better handling and storage methods can help eliminate contamination of the edible stink bug with the carcinogen aflatoxin and ensure its safety as human food.

  18. Status of the fluidized bed unit

    International Nuclear Information System (INIS)

    Williams, P.M.; Wade, J.F.

    1994-01-01

    Rocky Flats has a serious mixed waste problem. No technology or company has a license and available facilities to remedy this dilemma. One solution under study is to use a catalytic fluidized bed unit to destroy the combustible portion of the mixed waste. The fluidized bed thermal treatment program at Rocky Flats is building on knowledge gained over twenty years of successful development activity. The FBU has numerous technical advantages over other thermal technologies to treat Rocky Flats' mixed waste, the largest being the lower temperature (700 degrees C versus 1000 degrees C) which reduces acid corrosion and mechanical failures and obviates the need for ceramic lining. Successful demonstrations have taken place on bench, pilot, and full-scale tests using radioactive mixed wastes. The program is approaching implementation and licensing of a production-scale fluidized bed system for the safe treatment of mixed waste. The measure for success on this project is the ability to work closely with the community to jointly solve problems and respond to concerns of mixed waste treatment at Rocky Flats

  19. Advantages of forced non-steady operated trickle-bed reactors

    NARCIS (Netherlands)

    Boelhouwer, J.G.; Piepers, H.W.; Drinkenburg, A.A.H.

    2002-01-01

    Trickle-bed reactors are usually operated in the steady state trickle flow regime. Uneven liquid distribution and the formation of hot spots are the most serious problems experienced during trickle flow operation. In this paper, we advocate the use of non-steady state operation of trickle-bed

  20. Immune responses of a native and an invasive bird to Buggy Creek Virus (Togaviridae: Alphavirus and its arthropod vector, the swallow bug (Oeciacus vicarius.

    Directory of Open Access Journals (Sweden)

    Carol A Fassbinder-Orth

    Full Text Available Invasive species often display different patterns of parasite burden and virulence compared to their native counterparts. These differences may be the result of variability in host-parasite co-evolutionary relationships, the occurrence of novel host-parasite encounters, or possibly innate differences in physiological responses to infection between invasive and native hosts. Here we examine the adaptive, humoral immune responses of a resistant, native bird and a susceptible, invasive bird to an arbovirus (Buggy Creek virus; Togaviridae: Alphavirus and its ectoparasitic arthropod vector (the swallow bug; Oeciacus vicarius. Swallow bugs parasitize the native, colonially nesting cliff swallow (Petrochelidon pyrrhonota and the introduced house sparrow (Passer domesticus that occupies nests in cliff swallow colonies. We measured levels of BCRV-specific and swallow bug-specific IgY levels before nesting (prior to swallow bug exposure and after nesting (after swallow bug exposure in house sparrows and cliff swallows in western Nebraska. Levels of BCRV-specific IgY increased significantly following nesting in the house sparrow but not in the cliff swallow. Additionally, house sparrows displayed consistently higher levels of swallow bug-specific antibodies both before and after nesting compared to cliff swallows. The higher levels of BCRV and swallow bug specific antibodies detected in house sparrows may be reflective of significant differences in both antiviral and anti-ectoparasite immune responses that exist between these two avian species. To our knowledge, this is the first study to compare the macro- and microparasite-specific immune responses of an invasive and a native avian host exposed to the same parasites.

  1. Investigating Information Needs to Improve Cooperation Between Developers and Bug Reporters

    NARCIS (Netherlands)

    Breu, S.; Premraj, R.; Sillito, J.; Zimmermann, T.

    2010-01-01

    For many software projects, bug tracking systems play a central role in supporting collaboration between the developers and the users of the software. To better understand this collaboration and how tool support can be improved, we have quantitatively and qualitatively analysed the questions asked

  2. Ecosystem-based incorporation of nectar-producing plants for stink bug parasitoids

    Science.gov (United States)

    Adult parasitoids of pest insects rely on floral resources for survival and reproduction but can be food-deprived in intensively managed agricultural systems lacking these resources. Stink bugs are serious pests of crops in southwest Georgia. Provisioning nectar-producing plants for parasitoids of s...

  3. An Efficient Technique for Bayesian Modelling of Family Data Using the BUGS software

    Directory of Open Access Journals (Sweden)

    Harold T Bae

    2014-11-01

    Full Text Available Linear mixed models have become a popular tool to analyze continuous data from family-based designs by using random effects that model the correlation of subjects from the same family. However, mixed models for family data are challenging to implement with the BUGS (Bayesian inference Using Gibbs Sampling software because of the high-dimensional covariance matrix of the random effects. This paper describes an efficient parameterization that utilizes the singular value decomposition of the covariance matrix of random effects, includes the BUGS code for such implementation, and extends the parameterization to generalized linear mixed models. The implementation is evaluated using simulated data and an example from a large family-based study is presented with a comparison to other existing methods.

  4. Borehole-inclusion stressmeter measurements in bedded salt

    International Nuclear Information System (INIS)

    Cook, C.W.; Ames, E.S.

    1980-07-01

    Sandia purchased borehole-inclusion stressmeters from a commercial supplier to measure in situ stress changes in bedded salt. However, the supplied stressmeters were difficult to set in place and gave erratic results in bedded salt. These problems were overcome with a new extended platen design. Also a straingaged transducer was designed which can be read with a conventional data logger. Due to the nonlinear behavior of bedded salt under uniaxial loading, a new empirical calibration scheme was devised. In essence, the stressmeters are calibrated as force transducers and this calibration curve is then used to determine the relationship between uniaxial stress changes in bedded salt and the gage's output. The stressmeter and calibration procedures have been applied under mine conditions and produced viable results. Future work will involve finite element analysis to calculate the observed behavior of the stressmeters. The response of the stressmeters in bedded salt is neither that of a true stressmeter or of a true strainmeter. However, repeatable calibrations make the gages very useful

  5. An elementary introduction to Bayesian computing using WinBUGS.

    Science.gov (United States)

    Fryback, D G; Stout, N K; Rosenberg, M A

    2001-01-01

    Bayesian statistics provides effective techniques for analyzing data and translating the results to inform decision making. This paper provides an elementary tutorial overview of the WinBUGS software for performing Bayesian statistical analysis. Background information on the computational methods used by the software is provided. Two examples drawn from the field of medical decision making are presented to illustrate the features and functionality of the software.

  6. DIVERSITY OF THE SOUTHERN GREEN STINK BUG NEZARA VIRIDULA (L. (HETEROPTERA: PENTATOMIDAE

    Directory of Open Access Journals (Sweden)

    V MEGLIČ

    2002-05-01

    Full Text Available The southern green stink bug Nezara viridula (L. (Heteroptera: Pentatomidae is a global pest of considerable ecological, agricultural and economical interest. The ancestral home of this species is supposed to be Africa and/or Mediterranean and presumably it was spread worldwide during the last two centuries with human trade and agriculture. Bugs found today on different continents do not differ morphologically, however there are substantial differences in their mating behaviour. We used horizontal starch gel electrophoresis to determine the suitability of biochemical markers for assessment of genetic variation between geographically isolated populations of N. viridula. The initial survey of populations from Slovenia, France, French West Indies and Brazil resulted in the resolution of polymorphic banding patterns within the following enzyme systems: GPI, IDH, MDH, ME, MPI and PGM. Results indicate there are consistent differences among tested populations.

  7. Performance of Sandy Dry Beds for sludge dewatering

    International Nuclear Information System (INIS)

    Al-Muzaini, S.

    2003-01-01

    Sludge produced by the Jahra treatment plant was assessed. The assessment was directed at determining the performance of sand drying beds. The assessment of quality of the sludge produced was based on the standards for land application of sewage sludge. Analyses were carried out for trace heavy metals and bacteria. The results of analyses showed that the sludge produced was high in organic matter and sand content but low in heavy metals. The collected data indicated that the sand drying beds at the Jahra treatment plant are at present inadequate to handle the projected sludge production. The investigation showed that the sand drying beds are fully used and the plant will require 3-4 times the capacity of the existing drying beds when the plant becomes fully operational. In addition, these sand drying beds are subjected to uncontrollable conditions such as temperature, rainfall and sludge drainage rate. Thus, sand drying beds have become less popular as a dewatering system. This paper evaluates the performance of the existing sand drying beds and suggests the most appropriate technology to alleviate the above mentioned problems. (author)

  8. Countercurrent heat exchange and thermoregulation during blood-feeding in kissing bugs.

    Science.gov (United States)

    Lahondère, Chloé; Insausti, Teresita C; Paim, Rafaela Mm; Luan, Xiaojie; Belev, George; Pereira, Marcos H; Ianowski, Juan P; Lazzari, Claudio R

    2017-11-21

    Blood-sucking insects experience thermal stress at each feeding event on endothermic vertebrates. We used thermography to examine how kissing-bugs Rhodnius prolixus actively protect themselves from overheating. During feeding, these bugs sequester and dissipate the excess heat in their heads while maintaining an abdominal temperature close to ambient. We employed a functional-morphological approach, combining histology, µCT and X-ray-synchrotron imaging to shed light on the way these insects manage the flow of heat across their bodies. The close alignment of the circulatory and ingestion systems, as well as other morphological characteristics, support the existence of a countercurrent heat exchanger in the head of R. prolixus , which decreases the temperature of the ingested blood before it reaches the abdomen. This kind of system has never been described before in the head of an insect. For the first time, we show that countercurrent heat exchange is associated to thermoregulation during blood-feeding.

  9. Bug22p, a Conserved Centrosomal/Ciliary Protein Also Present in Higher Plants, Is Required for an Effective Ciliary Stroke in Paramecium ▿ †

    Science.gov (United States)

    Laligné, C.; Klotz, C.; Garreau de Loubresse, N.; Lemullois, M.; Hori, M.; Laurent, F. X.; Papon, J. F.; Louis, B.; Cohen, J.; Koll, F.

    2010-01-01

    Centrioles, cilia, and flagella are ancestral conserved organelles of eukaryotic cells. Among the proteins identified in the proteomics of ciliary proteins in Paramecium, we focus here on a protein, Bug22p, previously detected by cilia and basal-body high-throughput studies but never analyzed per se. Remarkably, this protein is also present in plants, which lack centrioles and cilia. Bug22p sequence alignments revealed consensus positions that distinguish species with centrioles/cilia from plants. In Paramecium, antibody and green fluorescent protein (GFP) fusion labeling localized Bug22p in basal bodies and cilia, and electron microscopy immunolabeling refined the localization to the terminal plate of the basal bodies, the transition zone, and spots along the axoneme, preferentially between the membrane and the microtubules. RNA interference (RNAi) depletion of Bug22p provoked a strong decrease in swimming speed, followed by cell death after a few days. High-speed video microscopy and morphological analysis of Bug22p-depleted cells showed that the protein plays an important role in the efficiency of ciliary movement by participating in the stroke shape and rigidity of cilia. The defects in cell swimming and growth provoked by RNAi can be complemented by expression of human Bug22p. This is the first reported case of complementation by a human gene in a ciliate. PMID:20118210

  10. Scaling of permeabilities and friction factors of homogeneously expanding gas-solids fluidized beds: Geldart’s A powders and magnetically stabilized beds

    Directory of Open Access Journals (Sweden)

    Hristov Jordan Y.

    2006-01-01

    Full Text Available The concept of a variable friction factor of fluid-driven de form able powder beds undergoing fluidization is discussed. The special problem discussed addresses the friction factor and bed permeability relationships of Geldart’s A powders and magnetically stabilized beds in axial fields. Governing equations and scaling relation ships are developed through three approaches (1 Minimization of the pressure drop with respect to the fluid velocity employing the Darcy-Forchheimer equation together with the Richardson-Zaki scaling law, (2 Minimization of the pres sure drop across an equivalent-channel replacing the actual packed beds by a straight pipe with bed-equivalent obstacle of a simple geometry, and (3 Entropy minimization method applied in cases of the Darcy-Forchheimer equation and the equivalent-channel model. Bed-to-surface heat transfer coefficients are commented in the context of the porosity/length scale relationships developed. Both the pressure drop curves developments and phase diagram de signs are illustrated by applications of the intersection of asymptotes technique to beds exhibiting certain degree of cohesion.

  11. Influence of Type of Electric Bright Light on the Attraction of the African Giant Water Bug, Lethocerus indicus (Hemiptera: Belostomatidae

    Directory of Open Access Journals (Sweden)

    Luke Chinaru Nwosu

    2012-01-01

    Full Text Available This study investigated the influence of type of electric bright light (produced by fluorescent light tube and incandescent light bulb on the attraction of the African giant water bug, Lethocerus indicus (Hemiptera: Belostomatidae. Four fluorescent light tubes of 15 watts each, producing white-coloured light and four incandescent light bulbs of 60 watts each, producing yellow-coloured light, but both producing the same amount of light, were varied and used for the experiments. Collections of bugs at experimental house were done at night between the hours of 8.30 pm and 12 mid-night on daily basis for a period of four months per experiment in the years 2008 and 2009. Lethocerus indicus whose presence in any environment has certain implications was the predominant belostomatid bug in the area. Use of incandescent light bulbs in 2009 significantly attracted more Lethocerus indicus 103 (74.6% than use of fluorescent light tubes 35 (25.41% in 2008 [4.92=0.0001]. However, bug’s attraction to light source was not found sex dependent [>0.05; (>0.18=0.4286 and >0.28=0.3897]. Therefore, this study recommends the use of fluorescent light by households, campgrounds, and other recreational centres that are potentially exposed to the nuisance of the giant water bugs. Otherwise, incandescent light bulbs should be used when it is desired to attract the presence of these aquatic bugs either for food or scientific studies.

  12. Tips for Travel

    Science.gov (United States)

    Avoid bringing bed bugs home by taking precautions when traveling such as inspecting bedding and luggage racks in hotel rooms, and upon returning home unpacking directly into a washing machine and dry at high temperatures.

  13. Using multiple bed load measurements: Toward the identification of bed dilation and contraction in gravel-bed rivers

    Science.gov (United States)

    Marquis, G. A.; Roy, A. G.

    2012-02-01

    This study examines bed load transport processes in a small gravel-bed river (Béard Creek, Québec) using three complementary methods: bed elevation changes between successive floods, bed activity surveys using tags inserted into the bed, and bed load transport rates from bed load traps. The analysis of 20 flood events capable of mobilizing bed material led to the identification of divergent results among the methods. In particular, bed elevation changes were not consistent with the bed activity surveys. In many cases, bed elevation changes were significant (1 to 2 times the D50) even if the bed surface had not been activated during the flood, leading to the identification of processes of bed dilation and contraction that occurred over 10% to 40% of the bed surface. These dynamics of the river bed prevent accurate derivation of bed load transport rates from topographic changes, especially for low magnitude floods. This paper discusses the mechanisms that could explain the dilation and contraction of particles within the bed and their implications in fluvial dynamics. Bed contraction seems to be the result of the winnowing of the fine sediments under very low gravel transport. Bed dilation seems to occur on patches of the bed at the threshold of motion where various processes such as fine sediment infiltration lead to the maintenance of a larger sediment framework volume. Both processes are also influenced by flood history and the initial local bed state and in turn may have a significant impact on sediment transport and morphological changes in gravel-bed rivers.

  14. Verde plant bug (Hemiptera: Miridae) feeding injury to cotton bolls characterized by boll age, size, and damage ratings.

    Science.gov (United States)

    Armstrong, J Scott; Brewer, Michael J; Parker, Roy D; Adamczyk, J J

    2013-02-01

    The verde plant bug, Creontiades signatus (Distant), has been present in south Texas for several years but has more recently been documented as an economic threat to cultivated cotton, (Gossypium hirsutum L. Our studies over 2 yr (2009 and 2010) and two locations (Weslaco and Corpus Christi, TX) investigated feeding-injury of the verde plant bug to a range of cotton boll age classes defined by boll diameter and accumulated degree-days (anthesis to the time of infesting) for first-position cotton bolls infested with the plant bugs. The most detrimental damage to younger cotton holls from verde plant bug feeding was boll abscission. Cotton bolls verde plant bug injured bolls compared with the controls up to 162 ACDD or a mean boll diameter 2.0 cm. Cotton seed weights were significantly reduced up to 179 ACDD or a boll diameter of 2.0 cm at Weslaco in 2009, and up to 317 ACDD or boll diameter 2.6 cm for Weslaco in 2010 when compared with the noninfested controls. Lint weight per cotton boll for infested and noninfested bolls was significantly reduced up to 262 ACDD or boll diameter 2.5 for Corpus Christi in 2010 and up to 288 ACCD or boll diameter 2.6 cm for Weslaco, TX, in 2010. Damage ratings (dependant variable) regressed against infested and noninfested seed-cotton weights showed that in every instance, the infested cotton bolls had a strong and significant relationship with damage ratings for all age classes of bolls. Damage ratings for the infested cotton bolls that did not abscise by harvest showed visual signs of verde plant bug feeding injury and the subsequent development ofboll rot; however, these two forms of injury causing lint and seed mass loss are hard to differentiate from open or boll-locked cotton bolls. Based on the results of both lint and seed loss over 2 yr and four studies cotton bolls should be protected up to approximately 300 ACDD or a boll diameter of 2.5 cm. This equilibrates to bolls that are 12-14 d of age dependent upon daily maximum

  15. The Heteroptera of the Netherlands Antilles – V Tingidae (Lace Bugs)

    NARCIS (Netherlands)

    Drake, Carl J.; Cobben, R.H.

    1960-01-01

    The present paper is based upon the lace bugs, Family Tingidae, collected by the junior author in the West Indies, on the islands of Aruba, Curaçao, Bonaire, St. Martin, Saba, and St. Eustatius. This collection of several tingids comprises 17 species, including the five new forms described below.

  16. Utilization of early soybeans for food and reproduction by the tarnished plant bug (Hemiptera: Miridae) in the delta of Mississippi.

    Science.gov (United States)

    Snodgrass, G L; Jackson, R E; Abel, C A; Perera, O P

    2010-08-01

    Commercially produced maturity group (MG) IV soybeans, Glycine max L., were sampled during bloom for tarnished plant bugs, Lygus lineolaris (Palisot de Beauvois), during May and June 1999 (3 fields) and 2001 (18 fields). The adults and nymphs were found primarily in single population peaks in both years, indicating a single new generation was produced during each year. The peak mean numbers of nymphs were 0.61 and 0.84 per drop cloth sample in 1999 and 2001, respectively. Adults peaked at 3.96 (1999) and 3.76 (2001) per sweep net sample (25 sweeps). Tests using laboratory-reared and field-collected tarnished plant bugs resulted in very poor survival of nymphs on 16 different soybean varieties (MG III, one; IV, four; V, nine; VI, two). A large cage (0.06 ha) field test found that the number of nymphs produced on eight soybean varieties after mated adults were released into the cages was lower than could be expected on a suitable host. These results indicated that soybean was a marginal host for tarnished plant bugs. However, the numbers of adults and nymphs found in the commercially produced fields sampled in the study may have been high enough to cause feeding damage to the flowering soybeans. The nature of the damage and its possible economic importance were not determined. Reproduction of tarnished plant bugs in the commercially produced early soybean fields showed that the early soybeans provided tarnished plant bugs with a very abundant host at a time when only wild hosts were previously available.

  17. A uranium bed with ceramic body for tritium storage

    Energy Technology Data Exchange (ETDEWEB)

    Khapov, A.S.; Grishechkin, S.K.; Kiselev, V.G. [' All Russia Research Institute of Automatics' - FSUE VNIIA, Moscow (Russian Federation)

    2015-03-15

    It is widely recognized that ceramic coatings provide an attractive solution to lower tritium permeation in structural materials. Alumina based ceramic coatings have the highest permeation reduction factor for hydrogen. For this reason an attempt was made to apply crack-free low porous ceramics as a structural material of a bed body for tritium storage in a setup used for hydrogenating neutron tube targets at VNIIA. The present article introduces the design of the bed. This bed possesses essentially a lower hydrogen permeation factor than traditionally beds with stainless steel body. Bed heating in order to recover hydrogen from the bed is suggested to be implemented by high frequency induction means. Inductive heating allows decreasing the time necessary for tritium release from the bed as well as power consumption. Both of these factors mean less thermal power release into glove box where a setup for tritium handling is installed and thus causes fewer problems with pressure regulations inside the glove box. Inductive heating allows raising tritium sorbent material temperature up to melting point. The latter allows achieving nearly full tritium recovery.

  18. Evaluating impacts of brown marmorated stink bug on non-fruiting nursery crops

    Science.gov (United States)

    Halyomorpha halys, commonly known as the brown marmorated stink bug (BMSB), has become a major pest and nuisance since it arrived in the US in 1998 for both agricultural growers and homeowners. They can feed on ~200 different plant species, several of which are important ornamental crop species. The...

  19. Populations of Rice Grain Bug, Paraeuscosmetus pallicomis, (Hemiptera: Lygaeidae) in Weed-free Paddy Field, Weedy Paddy Field and Paddy Dykes.

    Science.gov (United States)

    Abdullah, Tamrin; Nasruddin, Andi; Agus, Nurariaty

    2017-07-01

    Research on the populations of rice grain bug Paraeuscosmetus pallicomis Dallas (Hemiptera: Lygaeidae) in paddy field ecosystems was performed with the aim to determine the populations of rice grain bug in weed-free paddy field, weedy paddy field, and paddy dykes. Experiment was carried out in the village of Paccellekang in the district of Patallasang of Gowa Regency in South Sulawesi, Indonesia. Observations were performed during the milky grain stage (85 days after planting), the mature grain stage (105 days after planting), and one day after harvest (115 days after transplanting). Results showed that 85 days after the transplanting, the populations of rice grain bug was significantly higher in the weedy paddy field compared to weed-free field and paddy dykes with total numbers of 1.75, 3.53, and 0.31 insects per 2 hills, respectively. Similarly, 105 days after the transplanting, 2.53, 5.53, and 0.11 insects per hill, respectively. However, one day after the harvest (115 days after transplanting) the number of insects in weed-free field decreased, while in the dykes increased, and the weedy plot still had the highest number of insects per 2 hills. Our results suggested that weeds played an important role in regulating the bug population by providing alternative shelter and foods for the insect.

  20. Clinical physiology of bed rest

    Science.gov (United States)

    Greenleaf, John E.

    1993-01-01

    Maintenance of optimal health in humans requires the proper balance between exercise, rest, and sleep as well as time in the upright position. About one-third of a lifetime is spent sleeping; and it is no coincidence that sleeping is performed in the horizontal position, the position in which gravitational influence on the body is minimal. Although enforced bed rest is necessary for the treatment of some ailments, in some cases it has probably been used unwisely. In addition to the lower hydrostatic pressure with the normally dependent regions of the cardiovascular system, body fuid compartments during bed rest in the horizontal body position, and virtual elimination of compression on the long bones of the skeletal system during bed rest (hypogravia), there is often reduction in energy metabolism due to the relative confinement (hypodynamia) and alteration of ambulatory circadian variations in metabolism, body temperature, and many hormonal systems. If patients are also moved to unfamiliar surroundings, they probably experience some feelings of anxiety and some sociopsychological problems. Adaptive physiological responses during bed rest are normal for that environment. They are attempts by the body to reduce unnecessary energy expenditure, to optimize its function, and to enhance its survival potential. Many of the deconditioning responses begin within the first day or two of bed rest; these early responses have prompted physicians to insist upon early resumption of the upright posture and ambulation of bedridden patients.

  1. Scale insects and mealy bugs (Homoptera: Coccoidea) attacking deciduous fruit trees in the western north coast of Alexandria, Egypt.

    Science.gov (United States)

    Mourad, A K; Moursi Khadiga, S; Mesbah, H A; Abdel-Razak Soad, I

    2008-01-01

    This investigation covered a survey of scale insects and mealy bugs infesting ten growing species of deciduous fruit trees in three localities in Alexandria govemorate. These localities were Merghem, Burg El-Arab, and El-Nahda about 50 Km. West of Alexandria under both rain-fed and irrigation system conditions. The common inspected fruit trees were fig, white mulberry, pomegranate, apple, pear, apricot, European plum, peach, almond, and persimmon. It was shown that a group of twenty scale insects and meaty bug species pertaining to fifteen genera belonging to six families of the super family: Coccoidea were collected and identified during the elapsing period from January to December, 2004. Among these species, Diaspidiotus perniciosus (Comstock) was recorded for the first time in Egypt. In the present study, many insect and non-insect parasitoids and predators were also found associated with these scale insects and mealy bugs on deciduous fruit trees in the three concerned localities throughout this investigation. These natural enemies were identified and recorded.

  2. Strategies for fitting nonlinear ecological models in R, AD Model Builder, and BUGS

    Science.gov (United States)

    Bolker, Benjamin M.; Gardner, Beth; Maunder, Mark; Berg, Casper W.; Brooks, Mollie; Comita, Liza; Crone, Elizabeth; Cubaynes, Sarah; Davies, Trevor; de Valpine, Perry; Ford, Jessica; Gimenez, Olivier; Kéry, Marc; Kim, Eun Jung; Lennert-Cody, Cleridy; Magunsson, Arni; Martell, Steve; Nash, John; Nielson, Anders; Regentz, Jim; Skaug, Hans; Zipkin, Elise

    2013-01-01

    1. Ecologists often use nonlinear fitting techniques to estimate the parameters of complex ecological models, with attendant frustration. This paper compares three open-source model fitting tools and discusses general strategies for defining and fitting models. 2. R is convenient and (relatively) easy to learn, AD Model Builder is fast and robust but comes with a steep learning curve, while BUGS provides the greatest flexibility at the price of speed. 3. Our model-fitting suggestions range from general cultural advice (where possible, use the tools and models that are most common in your subfield) to specific suggestions about how to change the mathematical description of models to make them more amenable to parameter estimation. 4. A companion web site (https://groups.nceas.ucsb.edu/nonlinear-modeling/projects) presents detailed examples of application of the three tools to a variety of typical ecological estimation problems; each example links both to a detailed project report and to full source code and data.

  3. BED-time charts and their application to the problems of interruptions in external beam radiotherapy treatments

    International Nuclear Information System (INIS)

    Sinclair, Judith A.; Oates, Jason P.; Dale, Roger G.

    1999-01-01

    Purpose: The use of radiobiological modelling to examine the likely consequences of interruptions to radiotherapy schedules and to assess various compensatory measures. Methods and Materials: An effect-time graphical display, the BED-time chart, has been developed using the linear-quadratic (LQ) model. This is used to examine the effects on tumour and normal tissues of treatment interruption scenarios representative of clinical situations. The mathematical criteria governing successful salvage have also been drafted and applied to typical situations. Results: The successful salvage of an interrupted treatment is dependent on a number of interacting factors and the method presented here can be used to examine the trade-offs that exist. Although the mathematics may be complex, it is shown that the dilemmas posed by an interrupted treatment may be more easily appreciated with reference to BED-time charts. These may therefore have a useful role as a teaching aid for portraying a wider variety of radiotherapy problems and also in the documentation of interruptions to treatment and the measures taken to compensate for them. Conclusions: Interruptions to radiotherapy regimes are undesirable and compensatory measures need to be initiated as soon as possible after the gap, with a view to completing the amended treatment within the originally prescribed treatment time. Adequate compensation is particularly difficult for long gaps and gaps which occur towards the end of the scheduled treatment. Modelling exercises can help establish guidelines on the available windows of opportunity

  4. Plant growth stage-specific injury and economic injury level for verde plant bug, Creontiades signatus (Hemiptera: Miridae), on cotton: effect of bloom period of infestation.

    Science.gov (United States)

    Brewer, Michael J; Anderson, Darwin J; Armstrong, J Scott

    2013-10-01

    Verde plant bugs, Creontiades signatus Distant (Hemiptera: Miridae), were released onto caged cotton, Cossypium hirsutum L., for a 1-wk period to characterize the effects of insect density and bloom period of infestation on cotton injury and yield in 2011 and 2012, Corpus Christi, TX. When plants were infested during early bloom (10-11 nodes above first white flower), a linear decline in fruit retention and boll load and a linear increase in boll injury were detected as verde plant bug infestation levels increased from an average of 0.5 to 4 bugs per plant. Lint and seed yield per plant showed a corresponding decline. Fruit retention, boll load, and yield were not affected on plants infested 1 wk later at peak bloom (8-9 nodes above first white flower), even though boll injury increased as infestation levels increased. Second-year testing verified boll injury but not yield loss, when infestations occurred at peak bloom. Incidence of cotton boll rot, known to be associated with verde plant bug feeding, was low to modest (verde plant bug were important contributors to yield decline, damage potential was greatest during the early bloom period of infestation, and a simple linear response best described the yield response-insect density relationship at early bloom. Confirmation that cotton after peak bloom was less prone to verde plant bug injury and an early bloom-specific economic injury level were key findings that can improve integrated pest management decision-making for dryland cotton, at least under low-rainfall growing conditions.

  5. Rock bed heat accumulators. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Riaz, M.

    1977-12-01

    The principal objectives of the research program on rock bed heat accumulators (or RBHA) are: (1) to investigate the technical and economic feasibility of storing large amounts of thermal energy (in the tens of MWt range) at high temperature (up to 500/sup 0/C) over extended periods of time (up to 6 months) using native earth or rock materials; (2) to conduct studies to establish the performance characteristics of large rock bed heat accumulators at various power and temperature levels compatible with thermal conversion systems; and (3) to assess the materials and environmental problems associated with the operation of such large heat accumulators. Results of the study indicate that rock bed heat accumulators for seasonal storage are both technically and economically feasible, and hence could be exploited in various applications in which storage plays an essential role such as solar power and total energy systems, district and cogeneration heating systems.

  6. Possibility of removing condensate and scattered oil from gas-condensate field during bed flooding

    Energy Technology Data Exchange (ETDEWEB)

    Belkina, N.A.; Yagubov, M.S.

    1984-01-01

    The problem is set of evaluating the possible removal from the bed of scattered oil and condensate during flooding of the bed. For this purpose, an experimental study was made of the displacement by water from the porous medium of the oil and condensate saturating it. The obtained experimental results permit evaluation of the possible removal from the gas-condensate bed of scattered oil and condensate during flooding of the bed.

  7. The HACMS program: using formal methods to eliminate exploitable bugs.

    Science.gov (United States)

    Fisher, Kathleen; Launchbury, John; Richards, Raymond

    2017-10-13

    For decades, formal methods have offered the promise of verified software that does not have exploitable bugs. Until recently, however, it has not been possible to verify software of sufficient complexity to be useful. Recently, that situation has changed. SeL4 is an open-source operating system microkernel efficient enough to be used in a wide range of practical applications. Its designers proved it to be fully functionally correct, ensuring the absence of buffer overflows, null pointer exceptions, use-after-free errors, etc., and guaranteeing integrity and confidentiality. The CompCert Verifying C Compiler maps source C programs to provably equivalent assembly language, ensuring the absence of exploitable bugs in the compiler. A number of factors have enabled this revolution, including faster processors, increased automation, more extensive infrastructure, specialized logics and the decision to co-develop code and correctness proofs rather than verify existing artefacts. In this paper, we explore the promise and limitations of current formal-methods techniques. We discuss these issues in the context of DARPA's HACMS program, which had as its goal the creation of high-assurance software for vehicles, including quadcopters, helicopters and automobiles.This article is part of the themed issue 'Verified trustworthy software systems'. © 2017 The Authors.

  8. The HACMS program: using formal methods to eliminate exploitable bugs

    Science.gov (United States)

    Launchbury, John; Richards, Raymond

    2017-01-01

    For decades, formal methods have offered the promise of verified software that does not have exploitable bugs. Until recently, however, it has not been possible to verify software of sufficient complexity to be useful. Recently, that situation has changed. SeL4 is an open-source operating system microkernel efficient enough to be used in a wide range of practical applications. Its designers proved it to be fully functionally correct, ensuring the absence of buffer overflows, null pointer exceptions, use-after-free errors, etc., and guaranteeing integrity and confidentiality. The CompCert Verifying C Compiler maps source C programs to provably equivalent assembly language, ensuring the absence of exploitable bugs in the compiler. A number of factors have enabled this revolution, including faster processors, increased automation, more extensive infrastructure, specialized logics and the decision to co-develop code and correctness proofs rather than verify existing artefacts. In this paper, we explore the promise and limitations of current formal-methods techniques. We discuss these issues in the context of DARPA’s HACMS program, which had as its goal the creation of high-assurance software for vehicles, including quadcopters, helicopters and automobiles. This article is part of the themed issue ‘Verified trustworthy software systems’. PMID:28871050

  9. Infant's bed climate and bedding in the Japanese home.

    Science.gov (United States)

    Nakamura Ikeda, Rie; Fukai, Kiyoko; Okamoto Mizuno, Kazue

    2012-06-01

    to assess the bed climate of infants in their homes in Japan. descriptive, exploratory, non-experimental research design. the data were collected at the participants' homes under normal circumstances. nineteen healthy infants between the ages of two and five months. Their mothers, who joined a parenting class organised by a maternity clinic in Okayama, Japan, consented to participate in this study. we visited the infants' homes and interviewed their mothers concerning the types and use of bedding. The temperature and relative humidity of the bed climate at the back and foot of the bedding, and in the room were measured every minute for four consecutive days. Differences among the bed climates measured during three seasons (spring, summer, and autumn) were assessed by one-way analysis of variance. The bed temperature was higher for infants than for adults. No significant difference in temperature was noted among the three seasons. The bed temperature was about 36.0°C when waterproof sheets and futon mattresses for children or adult were used. The average relative humidity of the bed climate at the back was highest in summer, followed by that in spring and autumn; the differences were significant. The use of waterproof sheets and futon mattresses for children in summer increased the relative humidity to 80% or more. The use of infant beds, sunoko drainboards, and cotton futon mattresses in summer was effective in reducing the bed humidity. these results suggest that nurse-midwives should advise the parents on comfortable bed climates for their infants, as well as how to select and use bedding for them. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Natural insecticide based-leaves extract of Piper aduncum (Piperaceae in the control of stink bug brown soybean

    Directory of Open Access Journals (Sweden)

    Ludmila Porto Piton

    2014-11-01

    Full Text Available This research aimed to evaluate the insecticide potential of the leaves extract of Piper aduncum (L. (Piperaceae on development of brown stink bug, Euschistus heros (F., major pest in soybean crop in Mato Grosso State. For this a bioassay was conducted with eggs, nymphs and adults of this stink bug, using the concentrations 0.5; 1.0; 2.0; 4.0 and 8.0%, of the extract acetonic of P. aduncum and acetone for control. It was evaluated the numbers of unviable eggs, nymphs death and longevity, fecundity and fertility of the adults. In the immersing eggs bioassay, all concentrations greater than 1% unviable more than 70% of the eggs, while in the contact bioassay only 19% of the eggs were unviable in 8% concentration, differing of control. In nymphs bioassay the concentrations of 8% and 4% caused death of 72% and 52%, respectively. In adults bioassay all concentrations tested reduced significantly the survival and reproduction of the insects. Thus is evidence that P. aduncum is a potential plant for stink bug control, because it had deleterious action in all development phases on E. heros.

  11. A transcriptome survey spanning life stages and sexes of the Harlequin bug, Murgantia histrionica

    Science.gov (United States)

    The harlequin bug, Murgantia histrionica (Hahn), is an agricultural pest in the continental United States, particularly in southern states. Reliable gene sequence data are especially useful to the development of species-specific, environmentally friendly molecular biopesticides and effective biolure...

  12. No hospital is an island when it comes to Y2K bug

    Science.gov (United States)

    Silversides, A

    1999-01-01

    If a recent meeting on the millennium bug is any indication, Canada's health care facilities have plenty to worry about as the year 2,000 approaches. Topics discussed included the state of readiness within the health care sector and potential legal issues that may arise. PMID:9951449

  13. The Impact of Test Case Summaries on Bug Fixing Performance : An Empirical Investigation

    NARCIS (Netherlands)

    Panichella, S.; Panichella, A.; Beller, M.; Zaidman, A.E.; Gall, H.

    2015-01-01

    Automated test generation tools have been widely investigated with the goal of reducing the cost of testing activities. However, generated tests have been shown not to help developers in detecting and finding more bugs even though they reach higher structural coverage compared to manual testing. The

  14. The Impact of Test Case Summaries on Bug Fixing Performance : An Empirical Investigation

    NARCIS (Netherlands)

    Panichella, Sebastiano; Panichella, A.; Beller, M.M.; Zaidman, A.E.; Gall, Harald C.

    2016-01-01

    Automated test generation tools have been widely investigated with the goal of reducing the cost of testing activities. However, generated tests have been shown not to help developers in detecting and finding more bugs even though they reach higher structural coverage compared to manual testing.

  15. EPA Regulation of Bed Bug Pesticides

    Science.gov (United States)

    All pesticides must be registered by EPA before being sold and used in the U.S., other than those that rely on a limited set of active ingredients (so-called minimum risk pesticides). EPA reviews for safety and effectiveness.

  16. Bed Bugs: A Public Health Issue

    Science.gov (United States)

    Negative effects include allergic reactions to their bites, secondary infections from the bite reaction such as impetigo, and mental health impacts on people living in infested homes such as anxiety and insomnia.

  17. Wear oxidation of evaporator coils in fluidised bed captive power plants

    International Nuclear Information System (INIS)

    Ghosal, S.K.; De, P.K.

    2000-01-01

    Combustion of pulverised coal or gas to form steam in thermal power plants is a common practice. Corrosion of water-wall, superheater and reheater tubes is the typical problem faced in these power plants. Modification of process conditions, redesigning of equipment and selection of more corrosion resistant materials are few methods which have been tried to combat corrosion to a certain extent. Restricted heat transfer efficiency is another problem associated with these power plants. In order to bring upon improvements, fluidized bed combustors are being used in some advanced thermal power plants at present because of excellent combustion and heat transfer efficiencies. Even with low grade coals, higher combustion efficiency could be achieved in these combustors due to excellent gas/solid chemical reactivity at relatively low reaction temperatures. Further improvements in in-bed heat transfer and bed temperature uniformity have been possible with the use of sand in bed. However, erosion, corrosion and combined erosion/corrosion are some of the major modes of material degradation associated with these fluidized bed combustors using sand. Recently in a captive power unit using bubbling fluidized bed combustors containing sand, evaporator coils made of carbon steel were seen to be severely affected by erosion corrosion. The directional nature of metal removal from the studs, tube OD and ultimately the rupture of the thinned tube wall confirmed the above observation. Microstructural examinations showed loss of carbon at certain places including those near the leaked/punctured regions at the prevailing bed temperature of 850 deg C. This paper describes the detailed investigations carried out on wear oxidation phenomenon occurred in a captive thermal power plant using advanced bubbling fluidized bed combustors. (author)

  18. Cladistics and biogeography of the assassin bug genus Rasahus Amyot & Serville (Heteroptera: Reduviidae: Peiratinae)

    NARCIS (Netherlands)

    Morrone, J.J.; Coscarón, M. del C.

    1998-01-01

    The assassin bug genus Rasahus Amyot & Serville (Heteroptera: Reduviidae: Peiratinae) comprises 26 Neotropical species. A cladistic analysis of the genus was carried out using 63 characters from external morphology, body vestiture, and male and female genitalia, with the species considered as

  19. Side effects of kaolin particle films on apple orchard bug, beetle and spider communities

    NARCIS (Netherlands)

    Marko, V.; Bogya, S.; Kondorosy, E.; Blommers, L.H.M.

    2010-01-01

    The effects of multiple applications of hydrophobic kaolin particle film on apple orchard bug (Heteroptera), beetle (Coleoptera) and spider (Araneae) assemblages were studied in the Netherlands. Insecticide-free orchard plots served as a control. The kaolin applications significantly reduced the

  20. Analysis of wall-packed-bed thermal interactions

    International Nuclear Information System (INIS)

    Gorbis, Z.R.; Tillack, M.S.; Tehranian, F.; Abdou, M.A.

    1995-01-01

    One of the major issues remaining for ceramic breeder blankets involves uncertainties in heat transfer and thermomechanical interactions within the breeder and multiplier regions. Particle bed forms are considered in many reactor blanket designs for both the breeder and Be multiplier. The effective thermal conductivity of beds and the wall-bed thermal conductance are still not adequately characterized, particularly under the influence of mechanical stresses. The problem is particularly serious for the wall conductance between Be and its cladding, where the uncertainty can be greater than 50%. In this work, we describe a new model for the wall-bed conductance that treats the near-wall region as a finite-width zone. The model includes an estimate of the region porosity based on the number of contact points, and the contact area for smooth surfaces. It solves the heat conduction in a near-wall unit cell. The model is verified with existing data and used to predict the range of wall conductances expected in future simulation experiments and in reactor applications. (orig.)

  1. Studies of gamma emitters in the alluvial deposit and in water of the Bug River

    International Nuclear Information System (INIS)

    Chibowski, S.; Pawlik, M.

    1995-01-01

    Studies of the contents of gamma emitters in samples of water and deposit taken from the Bug River (in Poland only) are presented. The total γ-activity of deposits ranges from 120-650 Bq/kg and the average value is 350 Bq/kg. The elevated activity is chiefly due to the presence of natural radionuclides. The main artificial radionuclides are Cs-137 and Cs-134, whose contribution to the total activity ranges from 0.2 to 6%. The activity of waters samples is low, namely, 1.7-3.5 Bq/kg and is due to the presence of natural radionuclides. The heterogeneity of the distribution of natural and artificial radionuclides in the studies samples reveals the effect of economical and industrial activities on contamination of the Bug. (author). 7 refs, 1 fig., 4 tabs

  2. Electric versus hydraulic hospital beds: differences in use during basic nursing tasks.

    Science.gov (United States)

    Capodaglio, Edda Maria

    2013-01-01

    Biomechanical, postural and ergonomic aspects during real patient-assisting tasks performed by nurses using an electric versus a hydraulic hospital bed were observed. While there were no differences in the flexed postures the nurses adopted, longer performance times were recorded when electric beds were used. Subjective effort, force exertion and lumbar shear forces exceeding safety limits proved electric beds were superior. Patients' dependency level seemed to influence the type of nurses' intervention (duration and force actions), irrespective of the bed used. The nurses greatly appreciated the electric bed. Its use seemed to reduce the level of effort perceived during care giving and the postural load during critical subtasks. Ergonomics and organizational problems related to adopting electric beds in hospital wards should be addressed further to make their use more efficient.

  3. Morphometrics of the Southern Green Stink Bug [Nezara viridula (L.) (Hemiptera: Pentatomidae)] Stylet Bundle

    Science.gov (United States)

    The southern green stink bug, Nezara viridula (L.) (Hemiptera: Pentatomidae), is a cosmopolitan pest of high-value cash crops, including cotton (Gossypium hirsutum L.; Malvales: Malvaceae). The pest can ingest and transmit disease-causing bacterial and fungal pathogens of cotton. We hypothesized t...

  4. Fooling the harlequin bug (Hemiptera: Pentatomidae) using synthetic volatiles to alter host plant choice

    Science.gov (United States)

    Harlequin bug, Murgantia histrionica (Hahn) (Hemiptera: Pentatomidae), is a widespread invasive pest that feeds on a variety of brassicaceous crops and other plants. To understand olfactory cues which mediate host-finding, and possible utility in pest management, we deployed aggregation pheromone (m...

  5. Thermal-hydraulic considerations for particle bed reactors

    Science.gov (United States)

    Benenati, R.; Araj, K. J.; Horn, F.

    In the design of particle bed reactor (PBR) cores, consideration must be given to the gas coolant channels and their configuration. Neutronics analysis provides the relative volume fractions of the component materials, but these must be arranged in such a manner as to allow proper cooling of all components by the gas flow at relatively low pressure drops. The thermal hydraulic aspects of this problem are addressed. A description of the computer model used in the analysis of the steady state condition is also included. Blowdown tests on hot particle bed fuel elements were carried out and are described.

  6. Bed agglomeration characteristics of palm shell and corncob combustion in fluidized bed

    International Nuclear Information System (INIS)

    Chaivatamaset, Pawin; Sricharoon, Panchan; Tia, Suvit

    2011-01-01

    Bed particle agglomeration was studied experimentally in an atmospheric laboratory scale fluidized bed combustor using quartz sand as bed material. Palm shell and corncob were tested. The objectives of the study were (i) to describe the contributions of the biomass ash properties and the operating conditions on the bed agglomeration tendency in term of the bed defluidization time (t def ) and the extent of potassium accumulation in the bed (K/Bed) and (ii) to further elucidate the ash inorganic behaviors and the governing bed agglomeration mechanisms. Defluidization caused by the bed agglomeration was experienced in all experiments during combustion of these biomasses, as a consequence of the presence of potassium in biomass. The experimental results indicated that biomass ash characteristics were the significant influence on the bed agglomeration. The increasing bed temperature, bed particle size and static bed height and the decreasing fluidizing air velocity enhanced the bed agglomeration tendency. The SEM/EDS analyses on the agglomerates confirmed that the agglomeration was attributed to the formation of potassium silicate liquid enriched on the surface of quartz sand particles in conjunction with the high surface temperature of the burning biomass char particles. Thermodynamic examination based on the phase diagram analysis confirmed that the molten phase formation was responsible for the agglomeration. In this study, the high molten ash fraction resulting from the high potassium content in biomass promoted the agglomeration and thus defluidization. - Highlights: → Palm shell and corncob of Thailand are tested their bed agglomeration behaviors during fluidized bed combustion. → The increase of bed temperature, bed particle size and static bed height and the decrease of air velocity enhance bed agglomeration. → The formation of ash derived potassium silicate melts enriched on sand surface is the key process. → The collision between char and sand

  7. Evidence of environmental and vertical transmission of Burkholderia symbionts in the oriental chinch bug, Cavelerius saccharivorus (Heteroptera: Blissidae).

    Science.gov (United States)

    Itoh, Hideomi; Aita, Manabu; Nagayama, Atsushi; Meng, Xian-Ying; Kamagata, Yoichi; Navarro, Ronald; Hori, Tomoyuki; Ohgiya, Satoru; Kikuchi, Yoshitomo

    2014-10-01

    The vertical transmission of symbiotic microorganisms is omnipresent in insects, while the evolutionary process remains totally unclear. The oriental chinch bug, Cavelerius saccharivorus (Heteroptera: Blissidae), is a serious sugarcane pest, in which symbiotic bacteria densely populate the lumen of the numerous tubule-like midgut crypts that the chinch bug develops. Cloning and sequence analyses of the 16S rRNA genes revealed that the crypts were dominated by a specific group of bacteria belonging to the genus Burkholderia of the Betaproteobacteria. The Burkholderia sequences were distributed into three distinct clades: the Burkholderia cepacia complex (BCC), the plant-associated beneficial and environmental (PBE) group, and the stinkbug-associated beneficial and environmental group (SBE). Diagnostic PCR revealed that only one of the three groups of Burkholderia was present in ∼89% of the chinch bug field populations tested, while infections with multiple Burkholderia groups within one insect were observed in only ∼10%. Deep sequencing of the 16S rRNA gene confirmed that the Burkholderia bacteria specifically colonized the crypts and were dominated by one of three Burkholderia groups. The lack of phylogenetic congruence between the symbiont and the host population strongly suggested host-symbiont promiscuity, which is probably caused by environmental acquisition of the symbionts by some hosts. Meanwhile, inspections of eggs and hatchlings by diagnostic PCR and egg surface sterilization demonstrated that almost 30% of the hatchlings vertically acquire symbiotic Burkholderia via symbiont-contaminated egg surfaces. The mixed strategy of symbiont transmission found in the oriental chinch bug might be an intermediate stage in evolution from environmental acquisition to strict vertical transmission in insects. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  8. Cold acclimation increases cold tolerance independently of diapause programing in the bean bug, Riptortus pedestris.

    Science.gov (United States)

    Rozsypal, J; Moos, M; Goto, S G

    2017-10-17

    The bean bug (Riptortus pedestris) is a pest of soybeans and other legumes in Japan and other Asian countries. It enters a facultative adult diapause on exposure to short days. While photoperiodism and diapause are well understood in R. pedestris, knowledge of cold tolerance is very limited, as is information on the effect of diapause on cold tolerance. We examined the effect of photoperiod, cold acclimation, and feeding status on cold tolerance in R. pedestris. We found that cold acclimation significantly increased survival at -10°C in both long- and short-day adult R. pedestris. Since the difference in cold survival between long- and short-day cold-acclimated groups was only marginal, we conclude that entering diapause is not crucial for R. pedestris to successfully pass through cold acclimation and become cold tolerant. We observed similar effects in 5th instar nymphs, with both long- and short-day cold-acclimated groups surviving longer cold exposures compared with non-acclimated groups. Starvation, which was tested only in adult bugs, had only a negligible and negative impact on cold survival. Although cold tolerance significantly increased with cold acclimation in adult bugs, supercooling capacity unexpectedly decreased. Our results suggest that changes in supercooling capacity as well as in water content are unrelated to cold tolerance in R. pedestris. An analysis of metabolites revealed differences between the treatments, and while several metabolites markedly increased with cold acclimation, their concentrations were too low to have a significant effect on cold tolerance.

  9. Interpersonal Problems and Developmental Trajectories of Binge Eating Disorder

    Science.gov (United States)

    Blomquist, Kerstin K.; Ansell, Emily B.; White, Marney A.; Masheb, Robin M.; Grilo, Carlos M.

    2012-01-01

    Objective To explore associations between specific interpersonal constructs and the developmental progression of behaviors leading to binge eating disorder (BED). Method Eighty-four consecutively evaluated, treatment-seeking obese (BMI ≥ 30) men and women with BED were assessed with structured diagnostic and clinical interviews and completed a battery of established measures to assess the current and developmental eating- and weight-related variables as well as interpersonal functioning. Results Using the interpersonal circumplex structural summary method, amplitude, elevation, the affiliation dimension, and the quadratic coefficient for the dominance dimension were associated with eating and weight-related developmental variables. The amplitude coefficient and more extreme interpersonal problems on the dominance dimension (quadratic)—i.e., problems with being extremely high (domineering) or low in dominance (submissive)—were significantly associated with ayounger age at onset of binge eating, BED, and overweight as well as accounted for significant variance in age at binge eating, BED, and overweight onset. Greater interpersonal problems with having an overly affiliative interpersonal style were significantly associated with, and accounted for significant variance in, ayounger age at diet onset. Discussion Findings provide further support for the importance of interpersonal problems among adults with BED and converge with recent work highlighting the importance of specific types of interpersonal problems for understanding heterogeneity and different developmental trajectories of individuals with BED. PMID:22727087

  10. Biochemical characterisation of the tissue degrading enzyme, collagenase, in the spined soldier bug, Podisus maculiventris (Hemiptera: Pentatomidae

    Directory of Open Access Journals (Sweden)

    Ghamari Mahboob

    2014-07-01

    Full Text Available Podisus maculiventris (Say is a generalist predator attacking many insect species from different orders. The bug injects saliva into its prey's body. The ingested hemolymph and liquefied internal tissues pass through the bug's alimentary tract. Collagenase working on peptide bonds of collagen and basement membrane proteins, leads to the disintegration of the prey's internal organs. As yet, there is an almost complete lack of knowledge on the collagenase activity in P. maculiventris. The collagenase activity of the salivary glands and midgut was optimum at pH 8.0 which was congruent with the optimal pH of the total proteolytic activity of the salivary glands. More collagenolytic activity was determined in the posterior lobe of the salivary glands and anterior midgut. Significant inhibition of collagenolytic activity by ethylenediaminetetraacetic acid (EDTA revealed the enzyme is a metalloproteinase. The collagenase activity notably decreased when the bug went hungry. The salivary gland collagenase is a vital enzyme in extra-oral digestion and facilitates the action of other digestive enzymes. The midgut collagenase may be involved in the digestion of the ingested muscle fibers. The collagenase probably acts as an intoxicating agent in the saliva (venom of P. maculiventris. Paralysing toxins are present in the salivary gland secretion.

  11. Dynamic transition between fixed- and mobile-bed: mathematical and numerical aspects

    Science.gov (United States)

    Zugliani, Daniel; Pasqualini, Matteo; Rosatti, Giorgio

    2017-04-01

    Free-surface flows with high sediment transport (as debris flow or hyper-concentrated flow) are composed by a mixture of fluid and solid phase, usually water and sediment. When these flows propagate over loose beds, particles constituting the mixture of water and sediments strongly interact with the ones forming the bed, leading to erosion or deposition. However, there are lots of other situations when the mixture flows over rigid bedrocks or over artificially paved transects, so there is no mass exchange between bed and mixture. The two situations are usually referred to as, respectively, mobile- and fixed-bed conditions. From a mathematical point of view, the systems of Partial Differential Equations (PDEs) that describe these flows derive from mass and momentum balance of both phases, but, the two resulting PDEs systems are different. The main difference concerns the concentration: in the mobile-bed condition, the concentration is linked to the local flow conditions by means of a suitable rheological relation, while in the fixed-bed case, the concentration is an unknown of the problem. It is quite common that a free surface flow with high sediment transport, in its path, encounters both conditions. In the recent work of Rosatti & Zugliani 2015, the mathematical and numerical description of the transition between fixed- and mobile-bed was successfully resolved, for the case of low sediment transport phenomena, by the introduction of a suitable erodibility variable and satisfactory results were obtained. The main disadvantage of the approach is related to the erodibility variable, that changes in space, based on bed characteristics, but remains constant in time. However, the nature of the bed can change dynamically as result of deposition over fixed bed or high erosion over mobile bed. With this work, we extend the applicability of the mentioned approach to the more complex PDEs describing the hyper-concentrated flow. Moreover, we introduce a strategy that allows

  12. A case of extensive congregation of Man-faced Stink Bug Catacanthus incarnatus (Drury (Hemiptera: Pentatomidae together with new host records from western Maharashtra, India

    Directory of Open Access Journals (Sweden)

    S.H. Waghmare

    2015-06-01

    Full Text Available A study was conducted on the congregation of Stink Bug Catacanthus incarnatus. For the first time this bug was reported at high altitude i.e., 792m. The study reports the congregation of C. incarnatus on four new host plant species viz., Ixora brachiata, Memecylon umbellatum, Glochidion ellipticum and Olea dioica. More infestation was observed on I. brachiata. 

  13. Research and application of packing density for pebble bed in HTR

    International Nuclear Information System (INIS)

    Yu Fujiang; Xie Fei; Sun Ximing

    2015-01-01

    The pebble bed high temperature gas-cooled reactor is one of the major types of reactors developed by Chinese nuclear technology. The statistical analysis for packing density in the pebble bed is an important issue of physical-thermal calculation and safety analysis. Aimed to this problem, a new kind of method was set up to solve this problem. Compared with the traditional lattice-fill method and the experiment, its efficiency and accuracy were verified, while helping to find out the best length of unit in the traditional lattice-fill method. This method was used to analyze the boundary effects observed by experiments. (authors)

  14. Process and technological wastes compaction through a fluidized bed incineration process

    International Nuclear Information System (INIS)

    Guiroy, J.J.

    1993-01-01

    The various fluidized bed systems (dense or circulating) are reviewed and the advantages of the circulation fluidized bed are highlighted (excellent combustion performance, clean combustion, large operating range, poly-functionality with regards to waste type, ...). Applications to contaminated graphite (with the problem of ash management) and to plant process wastes (ion exchangers, technological wastes, aqueous effluents); study of the neutralization and chlorine emission

  15. Bed blocking by elderly patients in general-hospital wards.

    Science.gov (United States)

    Rubin, S G; Davies, G H

    1975-08-01

    A point prevalence survey, using a questionnaire, was performed in three general hospitals to investigate the problem of elderly patients blocking acute-hospital beds. A total of 1010 occupied general beds were surveyed and all patients, over the age of 60 years, who had been in hospital more than four weeks, and who, in the opinion of medical and nursing staff, were no longer in need of the facilities of a general hospital, were investigated. Forty-eight patients (4.8 per cent of the total) were found to be genuinely in bed inappropriate to their needs. Rehabilitation, together with assessment of these patients, appeared disorganized and lacked consistency, and decisions regarding suitable 'disposal' appeared to be made without sufficient consultation and conformed to no detectable pattern. The main reason for the continuing bed occupancy of the patients was the length of the waiting lists for alternative residential accommodation and the main single medical factor preventing discharge home or to a hostel was the problem of mobility. By interviewing staff and patients and scrutinizing the questionnaires, it was found that 23 patients (48 per cent) were only suitable for transfer to a long-stay hospital. Of these, however, 15 (31 per cent) could be placed in specialized accommodation if some degree of nursing care, at present not available, was provided.

  16. The Safety of Hospital Beds: Ingress, Egress, and In-Bed Mobility.

    Science.gov (United States)

    Morse, Janice M; Gervais, Pierre; Pooler, Charlotte; Merryweather, Andrew; Doig, Alexa K; Bloswick, Donald

    2015-01-01

    To explore the safety of the standard and the low hospital bed, we report on a microanalysis of 15 patients' ability to ingress, move about the bed, and egress. The 15 participants were purposefully selected with various disabilities. Bed conditions were randomized with side rails up or down and one low bed with side rails down. We explored the patients' use of the side rails, bed height, ability to lift their legs onto the mattress, and ability to turn, egress, and walk back to the chair. The standard bed was too high for some participants, both for ingress and egress. Side rails were used by most participants when entering, turning in bed, and exiting. We recommend that side rails be reconsidered as a means to facilitate in-bed movement, ingress, and egress. Furthermore, single deck height settings for all patients are not optimal. Low beds as a safety measure must be re-evaluated.

  17. Fast pyrolysis of biomass in fluidized bed reactor UNICAMP, Brazil: problems, causes and solutions; Pirolise rapida de biomassa em reator de leito fluidizado UNICAMP-Brasil: problemas, causas e solucoes

    Energy Technology Data Exchange (ETDEWEB)

    Mesa Perez, Juan Miguel; Marin Mesa, Henry Ramon [Bioware Tecnologia, Campinas, SP (Brazil); Rocha, Jose Dilcio; Olivares Gomez, Edgardo [Universidade Estadual de Campinas (NIPE/UNICAMP), SP (Brazil). Nucleo Interdisciplinar de Planejamento Energetico; Cortez, Luis Augusto Barbosa; Shimabukuro, Fabio Rodrigo; Vallin, Marco Jim Gui [Universidade Estadual de Campinas (FEAGRI/UNICAMP), SP (Brazil). Fac. de Engenharia Agricola

    2006-07-01

    The fluidized bed reactor developed by the researchers of the UNICAMP in the installations of the Sugar Cane Technology Center (CTC), in Piracicaba-SP, is the first reactor of biomass fast pyrolysis in Brazil to produce bio-oil. In this work the problems of operation with the reactor in functioning are presented as the emptying of gases produced in the pyrolysis by means of the biomass feeding system, the block of the thread of biomass feeding, the inert material sintering in the bed, etc. The possible causes are described. Thus it, the first ones could be solved, either by the reduction of the height of the inert bed, or by the increase of the wadding percentage of the thread, among others. These results of the exploratory tests make possible the steady work of the plant, greater knowledge of the phenomena that occur during the fast pyrolysis in flutizide bed, as well as the establishment of adjusted levels for the identified independent factors during the remaining experimental works. (author)

  18. A review of some parameters involved in fluidized bed bioreactors

    Energy Technology Data Exchange (ETDEWEB)

    Wright, P.C. [School of Chemical Engineering and Industrial Chemistry, The Univ. of New South Wales, Sydney (Australia); Raper, J.A. [School of Chemical Engineering and Industrial Chemistry, The Univ. of New South Wales, Sydney (Australia)

    1996-02-01

    Three-phase fluidized bed bioreactors have advantages over conventional chemical reaction systems. There is a lack of agreement over most major operational conditions, and a wide range of design variables are open to question. A large body of recent work in the field has been reviewed, with a degree of historical comparison and discussion. It has been found that aspects of fluidized bed biofilm reactors of vital importance include: choice of solid media, gas and liquid loadings, bacterial type and reactor mechanical design. A large proportion of the work in the field of three-phase fluidization is non-biologically specific, or not tested on a bacterially inoculated system. The majority of three-phase fluidized bed bioreactor work is in the field of water treatment. Although this work has highlighted the potential for use of bio-fluidized beds for this application, there are still specific problems hinderin the large scale industrial acceptance of three-phase fluidized bed bioreactors. (orig.)

  19. The nuclear dimension of the millennium bug: The Syrian experience

    International Nuclear Information System (INIS)

    Khudeir, I.

    1999-01-01

    Two nuclear facilities operated by the AECS have been investigated for the Y2K compliance. Computers and associated electronic systems in the Miniature Neutron Source Reactor and the Co-60 irradiator facility were examined. Real time clocks (BIOS) of the personal computers failed Y2K bug and needed to be manually rolled over January 1st 2000. Leap year checks, however were successful. Application software used by the operators for controlling facilities and performing measurements were able to function normally

  20. Application and Discussion of Dual Fluidized Bed Reactor in Biomass Energy Utilization

    Science.gov (United States)

    Guan, Haibin; Fan, Xiaoxu; Zhao, Baofeng; Yang, Liguo; Sun, Rongfeng

    2018-01-01

    As an important clean and renewable energy, biomass has a broad market prospect. The dual fluidized bed is widely used in biomass gasification technology, and has become an important way of biomass high-value utilization. This paper describes the basic principle of dual fluidized bed gasification, from the gas composition, tar content and thermal efficiency of the system point of view, analyzes and summarizes several typical dual fluidized bed biomass gasification technologies, points out the existence of gas mixing, the external heat source, catalyst development problems on gas. Finally, it is clear that the gasification of biomass in dual fluidized bed is of great industrial application and development prospect.

  1. Traveler's encounter with nymphs in a hotel bed.

    Science.gov (United States)

    Sandlund, Johanna; Banaei, Niaz

    2014-01-01

    This case illustrates skin lesions in a traveler staying in a hotel bed infested with tics. Although infestation of hotels with bedbugs belonging to the Cimex genus is a growing problem worldwide, tick infestation has never been reported before.

  2. Uncovering Bugs in Distributed Storage Systems during Testing (not in Production!)

    OpenAIRE

    Deligiannis, P; McCutchen, M; Thomson, P; Chen, S; Donaldson, AF; Erickson, J; Huang, C; Lal, A; Mudduluru, R; Qadeer, S; Schulte, W

    2016-01-01

    Testing distributed systems is challenging due to multiple sources of nondeterminism. Conventional testing techniques, such as unit, integration and stress testing, are ineffective in preventing serious but subtle bugs from reaching production. Formal techniques, such as TLA+, can only verify high-level specifications of systems at the level of logic-based models, and fall short of checking the actual executable code. In this paper, we present a new methodology for testing distributed systems...

  3. 7 CFR 2902.15 - Bedding, bed linens, and towels.

    Science.gov (United States)

    2010-01-01

    ... PROCUREMENT Designated Items § 2902.15 Bedding, bed linens, and towels. (a) Definition. (1) Bedding is that... minimum biobased content is 12 percent and shall be based on the amount of qualifying biobased carbon in..., and silk are not qualifying biobased feedstocks for the purpose of determining the biobased content of...

  4. Characterization of Halyomorpha halys (brown marmorated stink bug) biogenic volatile organic compound emissions and their role in secondary organic aerosol formation.

    Science.gov (United States)

    Solomon, Danielle; Dutcher, Dabrina; Raymond, Timothy

    2013-11-01

    The formation of aerosols is a key component in understanding cloud formation in the context of radiative forcings and global climate modeling. Biogenic volatile organic compounds (BVOCs) are a significant source of aerosols, yet there is still much to be learned about their structures, sources, and interactions. The aims of this project were to identify the BVOCs found in the defense chemicals of the brown marmorated stink bug Halymorpha halys and quantify them using gas chromatography-mass spectrometry (GC/MS) and test whether oxidation of these compounds by ozone-promoted aerosol and cloud seed formation. The bugs were tested under two conditions: agitation by asphyxiation and direct glandular exposure. Tridecane, 2(5H)-furanone 5-ethyl, and (E)-2-decenal were identified as the three most abundant compounds. H. halys were also tested in the agitated condition in a smog chamber. It was found that in the presence of 100-180 ppm ozone, secondary aerosols do form. A scanning mobility particle sizer (SMPS) and a cloud condensation nuclei counter (CCNC) were used to characterize the secondary aerosols that formed. This reaction resulted in 0.23 microg/ bug of particulate mass. It was also found that these secondary organic aerosol particles could act as cloud condensation nuclei. At a supersaturation of 1%, we found a kappa value of 0.09. Once regional populations of these stink bugs stablilize and the populations estimates can be made, the additional impacts of their contribution to regional air quality can be calculated.

  5. Doing bayesian data analysis a tutorial with R and BUGS

    CERN Document Server

    Kruschke, John K

    2011-01-01

    There is an explosion of interest in Bayesian statistics, primarily because recently created computational methods have finally made Bayesian analysis obtainable to a wide audience. Doing Bayesian Data Analysis, A Tutorial Introduction with R and BUGS provides an accessible approach to Bayesian data analysis, as material is explained clearly with concrete examples. The book begins with the basics, including essential concepts of probability and random sampling, and gradually progresses to advanced hierarchical modeling methods for realistic data. The text delivers comprehensive coverage of all

  6. Evaluation of a clay-based acidic bedding conditioner for dairy cattle bedding.

    Science.gov (United States)

    Proietto, R L; Hinckley, L S; Fox, L K; Andrew, S M

    2013-02-01

    This study investigated the effects of a clay-based acidic bedding conditioner on sawdust bedding pH, dry matter (DM), environmental pathogen counts, and environmental bacterial counts on teat ends of lactating dairy cows. Sixteen lactating Holstein cows were paired based on parity, days in milk, milk yield, and milk somatic cell count, and were negative for the presence of an intramammary pathogen. Within each pair, cows were randomly assigned to 1 of 2 treatments with 3-wk periods in a crossover design. Treatment groups consisted of 9 freestalls per group bedded with either untreated sawdust or sawdust with a clay-based acidic bedding conditioner, added at 3- to 4-d intervals over each 21-d period. Bedding and teat ends were aseptically sampled on d 0, 1, 2, 7, 14, and 21 for determination of environmental bacterial counts. At the same time points, bedding was sampled for DM and pH determination. The bacteria identified in the bedding material were total gram-negative bacteria, Streptococcus spp., and coliform bacteria. The bacteria identified on the teat ends were Streptococcus spp., coliform bacteria, and Klebsiella spp. Teat end score, milk somatic cell count, and intramammary pathogen presence were measured weekly. Bedding and teat cleanliness, environmental high and low temperatures, and dew point data were collected daily. The bedding conditioner reduced the pH, but not the DM, of the sawdust bedding compared with untreated sawdust. Overall environmental bacterial counts in bedding were lower for treated sawdust. Total bacterial counts in bedding and on teat ends increased with time over both periods. Compared with untreated sawdust, the treated bedding had lower counts of total gram-negative bacteria and streptococci, but not coliform counts. Teat end bacterial counts were lower for cows bedded on treated sawdust for streptococci, coliforms, and Klebsiella spp. compared with cows bedded on untreated sawdust. The clay-based acidic bedding conditioner

  7. India's first 100,000 lbs/hr atmospheric bed boiler

    International Nuclear Information System (INIS)

    Mahajan, S.K.

    1991-01-01

    This paper covers the operating experience at the Petrochemical Complex of Hindustan Polymers, a Member Company of the UB Group, India, on the India's first 100,000 Lbs/hr atmospheric fluidized bed boiler supplied by Bharat Heavy Electricals Ltd., India. This atmospheric fluidized bed boiler is in operation for over 7 years with over 51,000 operating hours. The paper covers the details of onstream hours, actual thermal efficiency achieved, type of coal used and operational advantages of such boilers as per experience of Hindustan Polymers. Paper also highlights the maintenance and equipment problems as well as the developments which have taken place to overcome such problems. Details of experience in the operation of this boiler with baghouse system using abrasive and high ash coal are also covered

  8. A new approach to define surface/sub-surface transition in gravel beds

    Science.gov (United States)

    Haynes, Heather; Ockelford, Anne-Marie; Vignaga, Elisa; Holmes, William

    2012-12-01

    The vertical structure of river beds varies temporally and spatially in response to hydraulic regime, sediment mobility, grain size distribution and faunal interaction. Implicit are changes to the active layer depth and bed porosity, both critical in describing processes such as armour layer development, surface-subsurface exchange processes and siltation/ sealing. Whilst measurements of the bed surface are increasingly informed by quantitative and spatial measurement techniques (e.g., laser displacement scanning), material opacity has precluded the full 3D bed structure analysis required to accurately define the surface-subsurface transition. To overcome this problem, this paper provides magnetic resonance imaging (MRI) data of vertical bed porosity profiles. Uniform and bimodal (σ g = 2.1) sand-gravel beds are considered following restructuring under sub-threshold flow durations of 60 and 960 minutes. MRI data are compared to traditional 2.5D laser displacement scans and six robust definitions of the surface-subsurface transition are provided; these form the focus of discussion.

  9. 75 FR 858 - Propoxur; Receipt of Application for Emergency Exemption; Solicitation of Public Comment

    Science.gov (United States)

    2010-01-06

    ... activity against bed bugs and would provide an effective insecticide in a different chemical class for bed... use of a pesticide which was voluntarily canceled under section 6(f) of the Federal Insecticide... section 18 of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) (7 U.S.C. 136p), at the...

  10. Bed-material entrainment and associated transportation infrastructure problems in streams of the Edwards Plateau, central Texas

    Science.gov (United States)

    Heitmuller, Franklin T.; Asquith, William H.

    2008-01-01

    The Texas Department of Transportation commonly builds and maintains low-water crossings (LWCs) over streams in the Edwards Plateau in Central Texas. LWCs are low-height structures, typically constructed of concrete and asphalt, that provide acceptable passage over seasonal rivers or streams with relatively low normal-depth flow. They are designed to accommodate flow by roadway overtopping during high-flow events. The streams of the Edwards Plateau are characterized by cobble- and gravel-sized bed material and highly variable flow regimes. Low base flows that occur most of the time occasionally are interrupted by severe floods. The floods entrain and transport substantial loads of bed material in the stream channels. As a result, LWCs over streams in the Edwards Plateau are bombarded and abraded by bed material during floods and periodically must be maintained or even replaced.

  11. Development and application of surrogate model for assessment of ex-vessel debris bed dryout probability - 15157

    International Nuclear Information System (INIS)

    Yakush, S.E.; Lubchenko, N.T.; Kudinov, P.

    2015-01-01

    In this work we consider a water-cooled power reactor severe accident scenario with pressure vessel failure and subsequent release of molten corium. A surrogate model for prediction of dryout heat flux for ex-vessels debris beds of different shapes is developed. Functional form of dryout heat flux dependence on problem parameters is developed by the analysis of coolability problem in non-dimensional variables. It is shown that for a flat debris bed the dryout heat flux can be represented in terms of three 1-dimensional functions for which approximating formulas are found. For two-dimensional debris beds (cylindrical, conical, Gaussian heap, mound-shaped), an additional function taking into account the bed shape geometry is obtained from numerical simulations using DECOSIM code as a full model. With the surrogate model in hand, risk analysis of debris bed coolability is carried out by Monte Carlo sampling of the input parameters within selected ranges, with assumed distribution functions

  12. Greater bottoms upgrading with Albemarle's e-bed catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Toshima, H.; Sedlacek, Z.; Backhouse, D.; Mayo, S.; Plantenga, F. [Albemarle Catalysts, Houston, TX (United States)

    2006-07-01

    The E-bed process is a heavy oil upgrading technology that produces near isothermal reactor conditions at a constant catalytic activity. However, E-bed conversion optimization is limited by reactor and downstream fouling problems caused by asphaltene precipitation. While asphaltene precipitation can controlled by reducing hydrogenation, high hydrogenation activity is needed for the removal of sulfur and heavy metals. This presentation described an asphaltene molecule management concept to reduce the fouling of E-bed units. Sediment reduction and high hydrogenation catalysts were used in a modified E-bed process with a variety of feeds and operating conditions. It was observed that the KF1312 catalyst achieved much higher sediment-reduction capability along with satisfactory hydrogenation activity with the different kinds of crude oil sources tested. The catalyst hydrocracked the asphaltenes into smaller molecules, which created greater asphaltene solubility. The sediment reduction capacity of the catalyst-staging technology is now being optimized. It was concluded that the technology will help to reduce fouling in E-bed processes and lead to improved conversion rates for refineries. refs., tabs., figs.

  13. Estimating potential stylet penetration of southern green stink bug (Hemiptera: Pentatomidae) - A mathematical modeling approach

    Science.gov (United States)

    Southern green stink bugs, Nezara viridula (L.), and related species are significant pests of cotton in the U.S. Cotton Belt. Using their stylets, adults introduce disease pathogens of cotton into cotton bolls, and preliminary data indicates nymphs can also ingest these pathogens. Data is lacking ...

  14. Improved design model for the multi-bed system in the storage and delivery system at ITER: Effects of decay of hydriding and dehydriding rate of a getter bed

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae-Uk [Department of Chemical Engineering, Pohang University of Science and Technology, San 31, Hyoja-Dong, Pohang 790-784 (Korea, Republic of); Chang, Min Ho; Yun, Sei-Hun [National Fusion Research Institute, 169-148-gil Kwahak-ro, Yusong-gu, Daejon 34133 (Korea, Republic of); Lee, Euy Soo, E-mail: eslee@dongguk.edu [Department of Chemical & Biochemical Engineering, Dongguk University, Seoul 100-715 (Korea, Republic of); Lee, In-Beum [Department of Chemical Engineering, Pohang University of Science and Technology, San 31, Hyoja-Dong, Pohang 790-784 (Korea, Republic of)

    2016-12-15

    This paper proposes an improved design model for the multi-bed system in the Storage and Delivery System considering that the hydriding and dehydriding rates of a getter bed decay over time. More specifically, the hydriding and dehydriding rates are influenced by the amount of remaining inventory in the getter bed and time simultaneously. Therefore, we formulate the rate decays mathematically to consider these features in the design model. The optimization problem is formulated as a mixed integer nonlinear program (MINLP) model with nonlinear constraints. Inductive operation scenario is presented to illustrate the applicability of the proposed model.

  15. Improved design model for the multi-bed system in the storage and delivery system at ITER: Effects of decay of hydriding and dehydriding rate of a getter bed

    International Nuclear Information System (INIS)

    Lee, Jae-Uk; Chang, Min Ho; Yun, Sei-Hun; Lee, Euy Soo; Lee, In-Beum

    2016-01-01

    This paper proposes an improved design model for the multi-bed system in the Storage and Delivery System considering that the hydriding and dehydriding rates of a getter bed decay over time. More specifically, the hydriding and dehydriding rates are influenced by the amount of remaining inventory in the getter bed and time simultaneously. Therefore, we formulate the rate decays mathematically to consider these features in the design model. The optimization problem is formulated as a mixed integer nonlinear program (MINLP) model with nonlinear constraints. Inductive operation scenario is presented to illustrate the applicability of the proposed model.

  16. Agglomeration mechanism in biomass fluidized bed combustion – Reaction between potassium carbonate and silica sand

    DEFF Research Database (Denmark)

    Anicic, Bozidar; Lin, Weigang; Dam-Johansen, Kim

    2018-01-01

    Agglomeration is one of the operational problems in fluidized bed combustion of biomass, which is caused by interaction between bed materials (e.g. silica sand) and the biomass ash with a high content of potassium species. However, the contribution of different potassium species to agglomeration ...

  17. An insight into the sialotranscriptome of the seed-feeding bug, Oncopeltus fasciatus

    OpenAIRE

    Francischetti, Ivo M.B.; Lopes, Angela H.; Dias, Felipe A.; Pham, Van M.; Ribeiro, José M.C.

    2007-01-01

    The salivary transcriptome of the seed-feeding hemipteran, Oncopeltus fasciatus (milkweed bug), is described following assembly of 1,025 ESTs into 305 clusters of related sequences. Inspection of these sequences reveals abundance of low complexity, putative secreted products rich in the amino acids (aa) glycine, serine or threonine, which might function as silk or mucins and assist food canal lubrication and sealing of the feeding site around the mouthparts. Several protease inhibitors were f...

  18. Purification performances of common reed beds based on the ...

    African Journals Online (AJOL)

    SARAH

    2013-11-30

    Nov 30, 2013 ... advantages, the reed bed is a solution to Beninese purification problems. Since technical service agent of ... Journal of Applied Biosciences 71:5682– 5691. ISSN 1997–5902 ..... 15N/14N ratios. Journal of Hydrology, vol. 199,.

  19. RNAi analysis of Deformed, proboscipedia and Sex combs reduced in the milkweed bug Oncopeltus fasciatus: novel roles for Hox genes in the hemipteran head.

    Science.gov (United States)

    Hughes, C L; Kaufman, T C

    2000-09-01

    Insects have evolved a large variety of specialized feeding strategies, with a corresponding variability in mouthpart morphology. We have, however, little understanding of the developmental mechanisms that underlie this diversity. Until recently it was difficult to perform any analysis of gene function outside of the genetic model insects Drosophila melanogaster and Tribolium castaneum. In this paper, we report the use of dsRNA-mediated interference (RNAi) to dissect gene function in the development of the milkweed bug Oncopeltus fasciatus, which has specialized suctorial mouthparts. The Hox genes Deformed (Dfd), proboscipedia (pb) and Sex combs reduced (Scr) have previously been shown to be expressed in the gnathal appendages of this species. Strikingly, the milkweed bug was found to have an unusual expression pattern of pb. Here, by analyzing single and combination RNAi depletions, we find that Dfd, pb and Scr are used in the milkweed bug to specify the identity of the mouthparts. The exact roles of the genes, however, are different from what is known in the two genetic model insects. The maxillary appendages in the bug are determined by the activities of the genes Dfd and Scr, rather than Dfd and pb as in the fly and beetle. The mandibular appendages are specified by Dfd, but their unique morphology in Oncopeltus suggests that Dfd's target genes are different. As in flies and beetles, the labium is specified by the combined activities of pb and Scr, but again, the function of pb appears to be different. Additionally, the regulatory control of pb by the other two genes seems to be different in the bug than in either of the other species. These novelties in Hox function, expression pattern and regulatory relationships may have been important for the evolution of the unique Hemipteran head.

  20. Comparative Mitogenomics of Plant Bugs (Hemiptera: Miridae): Identifying the AGG Codon Reassignments between Serine and Lysine

    Science.gov (United States)

    Wang, Pei; Song, Fan; Cai, Wanzhi

    2014-01-01

    Insect mitochondrial genomes are very important to understand the molecular evolution as well as for phylogenetic and phylogeographic studies of the insects. The Miridae are the largest family of Heteroptera encompassing more than 11,000 described species and of great economic importance. For better understanding the diversity and the evolution of plant bugs, we sequence five new mitochondrial genomes and present the first comparative analysis of nine mitochondrial genomes of mirids available to date. Our result showed that gene content, gene arrangement, base composition and sequences of mitochondrial transcription termination factor were conserved in plant bugs. Intra-genus species shared more conserved genomic characteristics, such as nucleotide and amino acid composition of protein-coding genes, secondary structure and anticodon mutations of tRNAs, and non-coding sequences. Control region possessed several distinct characteristics, including: variable size, abundant tandem repetitions, and intra-genus conservation; and was useful in evolutionary and population genetic studies. The AGG codon reassignments were investigated between serine and lysine in the genera Adelphocoris and other cimicomorphans. Our analysis revealed correlated evolution between reassignments of the AGG codon and specific point mutations at the antidocons of tRNALys and tRNASer(AGN). Phylogenetic analysis indicated that mitochondrial genome sequences were useful in resolving family level relationship of Cimicomorpha. Comparative evolutionary analysis of plant bug mitochondrial genomes allowed the identification of previously neglected coding genes or non-coding regions as potential molecular markers. The finding of the AGG codon reassignments between serine and lysine indicated the parallel evolution of the genetic code in Hemiptera mitochondrial genomes. PMID:24988409

  1. Computer games to teach hygiene: an evaluation of the e-Bug junior game

    OpenAIRE

    Farrell, D.; Kostkova, P.; Weinberg, J.; Lazareck, L.; Weerasinghe, D.; Lecky, D. M.; McNulty, C. A.

    2011-01-01

    Handwashing, respiratory hygiene and antibiotic resistance remain major public health concerns. In order to facilitate an effective outcome when teaching the basic principles of hand and respiratory hygiene, educational interventions should first target school children. As computer games are ubiquitous in most children's lives, e-Bug developed computer games targeted at teaching children handwashing, respiratory hygiene and antibiotic resistance. The games were designed for two target audienc...

  2. Could the bug Triatoma sherlocki be vectoring Chagas disease in small mining communities in Bahia, Brazil?

    Science.gov (United States)

    Almeida, C E; Folly-Ramos, E; Peterson, A T; Lima-Neiva, V; Gumiel, M; Duarte, R; Lima, M M; Locks, M; Beltrão, M; Costa, J

    2009-12-01

    Searches for Chagas disease vectors were performed at the type locality from which Triatoma sherlocki Papa et al. (Hemiptera: Reduviidae: Triatominae) was described in the municipality of Gentio do Ouro, in the state of Bahia, Brazil, and in a small artisan quarry-mining community approximately 13 km distant in a remote area of the same municipality. The latter site represents a new locality record for this species. Adults, nymphs and exuviae of T. sherlocki were found in 21% of human dwellings, indicating that the species is in the process of domiciliation. Prevalence of Trypanosoma cruzi infection in collected bugs was 10.8%. Simple predictive approaches based on environmental similarity were used to identify additional sites likely suitable for this species. The approach successfully predicted an additional five sites for the species in surrounding landscapes. Ecological and entomological indicators were combined to discuss whether this scenario likely represents an isolated case or an emerging public health problem.

  3. Simulating the 2012 High Plains drought using three single column versions (SCM) of BUGS5

    Science.gov (United States)

    Medina, I. D.; Denning, S.

    2013-12-01

    The impact of changes in the frequency and severity of drought on fresh water sustainability is a great concern for many regions of the world. One such location is the High Plains, where the local economy is primarily driven by fresh water withdrawals from the Ogallala Aquifer, which accounts for approximately 30% of total irrigation withdrawals from all U.S. aquifers combined. Modeling studies that focus on the feedback mechanisms that control the climate and eco-hydrology during times of drought are limited, and have used conventional General Circulation Models (GCMs) with grid length scales ranging from one hundred to several hundred kilometers. Additionally, these models utilize crude statistical parameterizations of cloud processes for estimating sub-grid fluxes of heat and moisture and have a poor representation of land surface heterogeneity. For this research, we will focus on the 2012 High Plains drought and will perform numerical simulations using three single column versions (SCM) of BUGS5 (Colorado State University (CSU) GCM coupled to the Simple Biosphere Model (SiB3)) at multiple sites overlying the Ogallala Aquifer for the 2011-2012 periods. In the first version of BUGS5, the model will be used in its standard bulk setting (single atmospheric column coupled to a single instance of SiB3), secondly, the Super-Parameterized Community Atmospheric Model (SP-CAM), a cloud resolving model (CRM consists of 64 atmospheric columns), will replace the single CSU GCM atmospheric parameterization and will be coupled to a single instance of SiB3, and for the third version of BUGS5, an instance of SiB3 will be coupled to each CRM column of the SP-CAM (64 CRM columns coupled to 64 instances of SiB3). To assess the physical realism of the land-atmosphere feedbacks simulated at each site by all versions of BUGS5, differences in simulated energy and moisture fluxes will be computed between the 2011 and 2012 period and will be compared to differences calculated using

  4. Unveiling Exception Handling Bug Hazards in Android Based on GitHub and Google Code Issues

    NARCIS (Netherlands)

    Coelho, R.; Almeida, L.; Gousios, G.; Van Deursen, A.

    2015-01-01

    This paper reports on a study mining the exception stack traces included in 159,048 issues reported on Android projects hosted in GitHub (482 projects) and Google Code (157 projects). The goal of this study is to investigate whether stack trace information can reveal bug hazards related to exception

  5. Effect of rolling bed on decubitus in bedridden nursing home patients.

    Science.gov (United States)

    Izutsu, T; Matsui, T; Satoh, T; Tsuji, T; Sasaki, H

    1998-02-01

    Decubitus is one of the most difficult management problems encountered in bedridden elderly patients. Relief of pressure over decubitus is the most important principle of the management. We developed a rolling air cushion bed which turns the patient to a 15-degree inclined lateral position with an inflating ripple mattress, a longitudinally aligned air inflatable tube. The position of the patients was changed between right and left laterals and to supine every 15 minutes automatically. Nineteen bedridden patients with decubitus used the rolling air cushion bed for 3 months and 12 bedridden patients with decubitus used a conventional bed and had their position changes every 2 hours by care givers. Severity of decubitus was divided into 4 grades and the decubitus significantly improved from 2.8 (S.E. 0.2) to 2.0 (S.E. 0.3) after 3 months in patients using the rolling air cushion bed, while in patients with conventional beds it changed from 3.0 (S.E. 0.2) to 3.2 (S.E. 0.2) (not statistically significant). We suggest that the rolling air cushion bed would be beneficial to decubitus relief in bedridden elderly and may relieve labor by care givers.

  6. Milkweed (Gentianales: Apocynaceae): a farmscape resource for increasing parasitism of stink bugs (Hemiptera: Pentatomidae) and providing nectar to insect pollinators and monarch butterflies.

    Science.gov (United States)

    Tillman, P G; Carpenter, J E

    2014-04-01

    In peanut-cotton farmscapes in Georgia, the stink bugs Nezara viridula (L.) and Chinavia hilaris (Say) (Hemiptera: Pentatomidae) and the leaffooted bug, Leptoglossus phyllopus (L.) (Hemiptera: Coreidae), disperse at crop-to-crop interfaces to feed on bolls in cotton. The main objective of this study was to determine whether insecticide-free tropical milkweed (Asclepias curassavica L.), a nectar-producing plant, can increase parasitism of these bugs by Trichopoda pennipes (F.) (Diptera: Tachinidae) and provide nectar to monarch butterflies and insect pollinators in these farmscapes. Peanut-cotton plots with and without flowering milkweed plants were established in 2009 and 2010. Adult T. pennipes, monarch butterflies, honey bees, and native insect pollinators readily fed on floral nectar of milkweed. Monarch larvae feeding on milkweed vegetation successfully developed into pupae. In 2009, N. viridula was the primary host of T. pennipes in cotton, and parasitism of this pest by the parasitoid was significantly higher in milkweed cotton (61.6%) than in control cotton (13.3%). In 2010, parasitism of N. viridula, C. hilaris, and L. phyllopus by T. pennipes was significantly higher in milkweed cotton (24.0%) than in control cotton (1.1%). For both years of the study, these treatment differences were not owing to a response by the parasitoid to differences in host density, because density of hosts was not significantly different between treatments. In conclusion, incorporation of milkweed in peanut-cotton plots increased stink bug parasitism in cotton and provided nectar to insect pollinators and monarch butterflies.

  7. Effects of setting new source performance standards for fluidized-bed combustion systems

    Energy Technology Data Exchange (ETDEWEB)

    1978-02-01

    This study was undertaken for the US Environmental Protection Agency to examine the potential consequences of revisions in New Source Performance Standards (NSPS) on fluidized-bed combustor-based steam electric generators of greater than 250,000,000 Btu. A study of the appropriateness and differential effects of alternate regulatory approaches to the standards-setting process was made. Problems dealing with an emerging technology such as fluidized-bed combustion were emphasized. Finally, an examination was made of the potential benefits of fluidized-bed combustion (FBC) systems relative to conventional coal-fired systems equipped with scrubbers. Information is included on the relative advantages and disadvantages of utility-sized fluidized-bed combustors, the technical consequences of NSPS alternatives, policy implications concerning NSPS for steam-electric generators, and cost models for atmospheric and pressurized FBC systems. (LCL)

  8. Preventing Run-Time Bugs at Compile-Time Using Advanced C++

    Energy Technology Data Exchange (ETDEWEB)

    Neswold, Richard [Fermilab

    2018-01-01

    When writing software, we develop algorithms that tell the computer what to do at run-time. Our solutions are easier to understand and debug when they are properly modeled using class hierarchies, enumerations, and a well-factored API. Unfortunately, even with these design tools, we end up having to debug our programs at run-time. Worse still, debugging an embedded system changes its dynamics, making it tough to find and fix concurrency issues. This paper describes techniques using C++ to detect run-time bugs *at compile time*. A concurrency library, developed at Fermilab, is used for examples in illustrating these techniques.

  9. Recovering stereo vision by squashing virtual bugs in a virtual reality environment

    OpenAIRE

    Vedamurthy, I; Knill, DC; Huang, SJ; Yung, A; Ding, J; Kwon, OS; Bavelier, D; Levi, DM

    2016-01-01

    Stereopsis is the rich impression of three-dimensionality, based on binocular disparity—the differences between the two retinal images of the same world. However, a substantial proportion of the population is stereo-deficient, and reliesmostly onmonocular cues to judge the relative depth or distance of objects in the environment. Here we trained adults who were stereo blind or stereodeficient owing to strabismus and/or amblyopia in a natural visuomotor task—a ‘bug squashing’ game—in a virtual...

  10. Dynamic longitudinal relations between binge eating symptoms and severity and style of interpersonal problems.

    Science.gov (United States)

    Luo, Xiaochen; Nuttall, Amy K; Locke, Kenneth D; Hopwood, Christopher J

    2018-01-01

    Despite wide recognition of the importance of interpersonal problems in binge eating disorder (BED), the nature of this association remains unclear. Examining the direction of this longitudinal relationship is necessary to clarify the role that interpersonal problems play in the course of binge eating problems, and thus to specify treatment targets and mechanisms. This study aimed to articulate the bidirectional, longitudinal associations between BED and both the general severity of interpersonal problems as well as warm and dominant interpersonal styles. Severity and styles of interpersonal problems and BED symptoms were measured at baseline, 12 weeks, 24 weeks, and 36 weeks in a sample of 107 women in treatment for BED. Results from bivariate latent change score models indicated that interpersonal problem severity and BED symptoms are associated longitudinally but do not directly influence each other. The results indicated a bidirectional interrelation between binge eating symptoms and dominance such that less dominance predicted greater decreases in binge eating problems, and less binge eating symptoms predicted greater increases in dominance. We also found that binge eating symptoms positively predicted changes in warmth (i.e., less binge eating symptoms predicted less increases or more decreases in warmth). These findings highlight the importance of using dynamic models to examine directionality and delineate the distinct roles of interpersonal severity and styles in BED trajectories. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  11. Instability and the formation of bubbles and the plugs in fluidized beds

    Directory of Open Access Journals (Sweden)

    Piotr Schulz

    2004-01-01

    Full Text Available This is an review paper, particulary concentrate on results not many researches by reason that are explain in the text. We consider stability of disperse, two-phase flow (gas-solid particles or liquid-solid particles linear and non-linear. In particular we discuss the result of Anderson, Sundareson and Jackson (1995 [Anderson K., Sundareson S., Jackson R.: Instabilities and the formation of bubbles in fluidized beds. J. Fluid Mech. 303 (1995, 327-366] that for vertical dispersion flow one- and two-dimensional, they attack problem growing disturbances directly by numerical integration of equations of motion from given initial conditions (using computer Cray C-90. In principle, this would allow authors to explore all aspects of dynamical behaviour of fluidized beds. It is interesting mechanism of periodic plug describing by Anderson et al. and attest by other researchers. Second part of paper is more general, dedicate the problem of linear stability of uniformly fluidized state ("fluidized bed". We make the most important stages of calculations (after to Jackson (2000 [Jackson R.: The Dynamics of Fluidized Particles. Cambridge University Press 2000] and demonstrate that the majority (but not all of fluidized beds with parameters having technical importance is unstable, or stable in narrow interval of wave numbers \\(k\\.

  12. Management bedding : vrijloopstal met composterende bedding van houtsnippers

    NARCIS (Netherlands)

    Boer, de H.C.; Wiersma, M.; Galama, P.J.; Szanto, G.L.

    2015-01-01

    In de vrijloopstal liggen de koeien meestal op een organische bedding en scheiden daar mest (feces en urine) uit. Om de bedding voldoende droog en schoon te houden wordt er regelmatig nieuw strooisel aangevoerd en wordt de toplaag bewerkt. Op basis van onderzoek- en praktijkervaringen tot nu toe

  13. Head of the bed elevation angle recorder for intensive care unit

    Science.gov (United States)

    Krefft, Maciej; Zamaro-Michalska, Aleksandra; Zabołotny, Wojciech M.; Zaworski, Wojciech; Grzanka, Antoni; Łazowski, Tomasz; Tavola, Mario; Siewiera, Jacek; Mikaszewska-Sokolewicz, Małgorzata

    2013-10-01

    This paper presents a recording system optimized for long term measurement of bed headrest elevation angle in the Intensive Care Unit. The continuous monitoring of this parameter allows to find the correlation between the patient's position in bed and the risk of the Ventilator Associated Pneumonia (VAP), a very serious problem in therapy of critically ill patients. Recorder might be be an important tool to evaluate the "care bundles" - sets of preventive procedures recommended for treatment of patients in the ICU.

  14. Biological control program is being developed for brown marmorated stink bug

    OpenAIRE

    Lara, Jesus; Pickett, Charlie; Ingels, Chuck; Haviland, David R; Grafton-Cardwell, Elizabeth E; Doll, David A; Bethke, James A; Faber, Ben; Dara, Surendra K; Hoddle, Mark

    2016-01-01

    Brown marmorated stink bug (BMSB) is an invasive, polyphagous pest that has been detected in 42 U.S. states. In 2010, it caused millions of dollars in crop damages to apple growers on the East Coast, where it arrived from Asia during the 1990s. In 2002, BMSB was reported in California; since then, it has been detected in 28 counties and is established in at least nine counties. Although this pest has not yet been found on commercial crops in the state, detections of BMSB in commercial orchard...

  15. Millennial angst? Insidious Y2K computer bug could have devastating consequences if not remedied

    International Nuclear Information System (INIS)

    Ross, E.

    1999-01-01

    The threat of the Y2K bug facing the petroleum industry was discussed. The bug can potentially affect every aspect of the industry relying on computerized and automated systems and equipment, from production to transportation. The importance for oil companies to establish contingency plans was emphasized. For example, Enbridge Energy Inc. is planning to be Y2K ready on all mission critical systems by June 1999. On the pipeline side, this means anything dealing with physical safety and the operational reliability of the pipeline. Canadian Occidental Petroleum Ltd., has tested everything dealing with environmental or public safety risk and regularly checks on how their suppliers are progressing with Y2K compliance. Companies will also face regulatory requirements, For example, the Alberta Energy and Utilities Board will be checking on 127 companies considered high risk, primarily for safety reasons. This includes operators of sour gas plants or pipelines and gas or electrical utilities. The upstream petroleum industry generally, is reported to be making good progress in addressing the issue

  16. How Do Visitors Relate to Biodiversity Conservation? An Analysis of London Zoo's "BUGS" Exhibit

    Science.gov (United States)

    Chalmin-Pui, Lauriane Suyin; Perkins, Richard

    2017-01-01

    Using a case study of London Zoo's BUGS (Biodiversity Underpinning Global Survival) exhibit, this article assesses the role of experiential learning in raising biodiversity knowledge, concern and potential pro-conservation actions. Using Personal Meaning Mindmapping, a novel method in visitor research, the study examines how adult visitors relate…

  17. Recovering stereo vision by squashing virtual bugs in a virtual reality environment.

    Science.gov (United States)

    Vedamurthy, Indu; Knill, David C; Huang, Samuel J; Yung, Amanda; Ding, Jian; Kwon, Oh-Sang; Bavelier, Daphne; Levi, Dennis M

    2016-06-19

    Stereopsis is the rich impression of three-dimensionality, based on binocular disparity-the differences between the two retinal images of the same world. However, a substantial proportion of the population is stereo-deficient, and relies mostly on monocular cues to judge the relative depth or distance of objects in the environment. Here we trained adults who were stereo blind or stereo-deficient owing to strabismus and/or amblyopia in a natural visuomotor task-a 'bug squashing' game-in a virtual reality environment. The subjects' task was to squash a virtual dichoptic bug on a slanted surface, by hitting it with a physical cylinder they held in their hand. The perceived surface slant was determined by monocular texture and stereoscopic cues, with these cues being either consistent or in conflict, allowing us to track the relative weighting of monocular versus stereoscopic cues as training in the task progressed. Following training most participants showed greater reliance on stereoscopic cues, reduced suppression and improved stereoacuity. Importantly, the training-induced changes in relative stereo weights were significant predictors of the improvements in stereoacuity. We conclude that some adults deprived of normal binocular vision and insensitive to the disparity information can, with appropriate experience, recover access to more reliable stereoscopic information.This article is part of the themed issue 'Vision in our three-dimensional world'. © 2016 The Author(s).

  18. Recovering stereo vision by squashing virtual bugs in a virtual reality environment

    Science.gov (United States)

    Vedamurthy, Indu; Knill, David C.; Huang, Samuel J.; Yung, Amanda; Ding, Jian; Kwon, Oh-Sang; Bavelier, Daphne

    2016-01-01

    Stereopsis is the rich impression of three-dimensionality, based on binocular disparity—the differences between the two retinal images of the same world. However, a substantial proportion of the population is stereo-deficient, and relies mostly on monocular cues to judge the relative depth or distance of objects in the environment. Here we trained adults who were stereo blind or stereo-deficient owing to strabismus and/or amblyopia in a natural visuomotor task—a ‘bug squashing’ game—in a virtual reality environment. The subjects' task was to squash a virtual dichoptic bug on a slanted surface, by hitting it with a physical cylinder they held in their hand. The perceived surface slant was determined by monocular texture and stereoscopic cues, with these cues being either consistent or in conflict, allowing us to track the relative weighting of monocular versus stereoscopic cues as training in the task progressed. Following training most participants showed greater reliance on stereoscopic cues, reduced suppression and improved stereoacuity. Importantly, the training-induced changes in relative stereo weights were significant predictors of the improvements in stereoacuity. We conclude that some adults deprived of normal binocular vision and insensitive to the disparity information can, with appropriate experience, recover access to more reliable stereoscopic information. This article is part of the themed issue ‘Vision in our three-dimensional world’. PMID:27269607

  19. Production of renewable energy from biomass and waste materials using fluidized bed technologies

    International Nuclear Information System (INIS)

    Rozainee, M.; Rashid, M.; Looi, S.

    2000-01-01

    Malaysian industries generate substantial amount of biomass and waste materials such as wastes from agricultural and wood based industries, sludge waste from waste-water treatment plants and solid waste from municipals. Incinerating these waste materials not only produces renewable energy, but also solving their disposal problems. Fluidized bed combustors are widely used for incinerating these biomass materials. The significant advantages of fluidized bed incineration include simple design, efficient, and ability to reduce air pollution emissions. This paper discusses the opportunities and challenges of producing the green energy from biomass materials using the fluidized bed technologies. (Author)

  20. Effect of bed particles to combustion of gases in fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Raiko, R.; Wallen, V.; Etelaeaho, R.; Correia, S. [Tampere Univ. of Technology (Finland). Energy and Process Engineering

    1997-10-01

    The objective of this project was to obtain experimental data on effects of sand particles to the combustion of gases. The effect of the surface area of the particles was tested using different sized particles. The fluidized bed reactor used in these experiments was a stainless-steel tube with an internal diameter of 42 mm surrounded by an electric heater. The test rig was built in the Laboratory of Energy and Process Engineering at Tampere University of Technology. In order to elucidate the possible changes of particle surface, microscopic and porosimetric studies were conducted with both fresh bed particles and used bed particles. These measurements indicate that carbon monoxide significantly reacts with oxygen in the particulate or emulsion phase of a fluidized bed, if the residence time is long enough. The reaction rate depends mainly on temperature, air coefficient, residence time and particle size of the solids. It seems that the combustion enhances if the average particle size increases. Whether this is caused by increased free path length or reduced specific surface area of the bed is yet unknown. The first might be more probable cause because the majority of reactions often took place in the freeboard right above the bed. It was clear that the bed hindered proper combustion in several cases. (orig.)

  1. Security Vulnerability Profiles of Mission Critical Software: Empirical Analysis of Security Related Bug Reports

    Science.gov (United States)

    Goseva-Popstojanova, Katerina; Tyo, Jacob

    2017-01-01

    While some prior research work exists on characteristics of software faults (i.e., bugs) and failures, very little work has been published on analysis of software applications vulnerabilities. This paper aims to contribute towards filling that gap by presenting an empirical investigation of application vulnerabilities. The results are based on data extracted from issue tracking systems of two NASA missions. These data were organized in three datasets: Ground mission IVV issues, Flight mission IVV issues, and Flight mission Developers issues. In each dataset, we identified security related software bugs and classified them in specific vulnerability classes. Then, we created the security vulnerability profiles, i.e., determined where and when the security vulnerabilities were introduced and what were the dominating vulnerabilities classes. Our main findings include: (1) In IVV issues datasets the majority of vulnerabilities were code related and were introduced in the Implementation phase. (2) For all datasets, around 90 of the vulnerabilities were located in two to four subsystems. (3) Out of 21 primary classes, five dominated: Exception Management, Memory Access, Other, Risky Values, and Unused Entities. Together, they contributed from 80 to 90 of vulnerabilities in each dataset.

  2. Bed retained products in swept fixed bed (SFB) coal hydropyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Mastral, A.M.; Perez-Surio, M.J. [CSIC, Zaragosa (Spain). Inst. de Carboquimica

    1997-12-31

    The hydropyrolysis of a low rank coal in a swept fixed bed (SFB) reactor is carried out by fixing the hydrogen pressure (40 kg/cm{sup 2}), the hydrogen flow (2 l/min) and the residence time (10 min) at increasing temperatures (400 C, 500 C and 600 C) and coal bed heights (h, 1.5h, 2h, 2.5h and 3h). It is shown that the percentages of tars and char directly depend on the coal bed height and that there is not only a quantitative dependence, but also the height of the coal bed is very important and plays a relevant role on the nature of the conversion products. (orig.)

  3. Competition between the phytophagous stink bugs Euschistus heros and Piezodorus guildinii in soybeans.

    Science.gov (United States)

    Tuelher, Edmar S; Silva, Éder H; Hirose, Edson; Guedes, Raul Narciso C; Oliveira, Eugênio E

    2016-10-01

    The abundance and contribution of the neotropical brown stink bug, Euschistus heros (F.), and the redbanded stink bug, Piezodorus guildinii (West.), to the composition of insect pests of soybean, Glycine max (L.), fields have changed both spatially and temporally in neotropical soybean production areas. Therefore, we assessed the competitiveness of each species in direct competition experiments following an additive series. We performed mixed (adult) insect infestations in soybean plants and evaluated the fitness of each species and the soybean yield. While the competitive ability of E. heros was significantly compromised by increments in conspecifics and heterospecifics (i.e. P. guildinii), the competitive ability of P. guildinii was compromised by the presence of heterospecifics (i.e. E. heros). The reproductive output of P. guildinii remained unaffected by increments in E. heros or of P. guildinii. Intriguingly, despite the fact that P. guildinii apparently lost the competition with E. heros, almost no pod production was observed in any plant colonised by the former. The higher abundance of E. heros in neotropical soybean fields seems to result from higher competitive ability than its heterospecific competitor P. guildinii, which may prevent the higher losses caused by P. guildinii. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  4. In-bed accountability of tritium in production scale metal hydride storage beds

    International Nuclear Information System (INIS)

    Klein, J.E.

    1995-01-01

    An ''in-bed accountability'' (IBA) flowing gas calorimetric measurement method has been developed and implemented to eliminate the need to remove tritium from production scale metal hydride storage beds for inventory measurement purposes. Six-point tritium IBA calibration curves have been completed for two, 390 gram tritium metal hydride storage beds. The calibration curves for the two tritium beds are similar to those obtained from the ''cold'' test program. Tritium inventory errors at the 95 percent confidence level ranged from ± 7.3 to 8.6 grams for the cold test results compared to ± 4.2 to 7.5 grams obtained for the two tritium calibrated beds

  5. The Kaldnes Moving Bed biofilm technology for treatment of industrial wastewater; Tecnologia Kaldnes Moving Bed biofilm (KMT) para la depuracion de aguas residuales industriales

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, V.; Garcia Carrion, M.; Farre Solsona, C.

    2004-07-01

    The Kaldnes Moving bed biofilm technology is a biofilm process which is very suitable for treatment of industrial wastewaters. Biofilm processes have several acknowledged advantages compared to suspended biomass processes, e. g. resistance to toxicity and load variations. Traditionally biofilm processes have been known to clog at high loads and hence have not been suited for industrial effluents: however, the Kaldnes Moving Bed biofilm process has overcome this problem. This article describes how the process has been used as pre-treatment up front of activated sludge at a dairy in USA, and as sole treatment at pharmaceutical industry in Sweden. (Author)

  6. Thermal Analysis of Fluidized Bed and Fixed Bed Latent Heat Thermal Storage System

    Science.gov (United States)

    Beemkumar, N.; Karthikeyan, A.; Shiva Keshava Reddy, Kota; Rajesh, Kona; Anderson, A.

    2017-05-01

    Thermal energy storage technology is essential because its stores available energy at low cost. Objective of the work is to store the thermal energy in a most efficient method. This work is deal with thermal analysis of fluidized bed and fixed bed latent heat thermal storage (LHTS) system with different encapsulation materials (aluminium, brass and copper). D-Mannitol has been used as phase change material (PCM). Encapsulation material which is in orbicular shape with 4 inch diameter and 2 mm thickness orbicular shaped product is used. Therminol-66 is used as a heat transfer fluid (HTF). Arrangement of encapsulation material is done in two ways namely fluidized bed and fixed bed thermal storage system. Comparison was made between the performance of fixed bed and fluidized bed with different encapsulation material. It is observed that from the economical point of view aluminium in fluidized bed LHTS System has highest efficiency than copper and brass. The thermal energy storage system can be analyzed with fixed bed by varying mass flow rate of oil paves a way to find effective heat energy transfer.

  7. Bed care for patients in palliative settings: considering risks to caregivers and bed surfaces.

    Science.gov (United States)

    Fragala, Guy

    2015-02-01

    Ensuring patients are comfortable in bed is key to effective palliative care, but when moving and positioning patients in bed, health professionals face an occupational risk of injury. The turning and positioning (TAP) system is a new method of moving patients in bed, that evidence has shown to reduce the risk of injury to caregivers. Providing the correct bed surface is another aspect of bed care essential to the comfort of the palliative patient, and to aid wound prevention and treatment. It is important to take a patient-centred approach when considering the most appropriate bed surface patients. This article provides an overview and discussion of these two aspects of bed care for palliative patients.

  8. Fluid bed porosity equation for an inverse fluidized bed bioreactor with particles growing biofilm

    International Nuclear Information System (INIS)

    Campos-Diaz, K. E.; Limas-Ballesteros, R.

    2009-01-01

    Fluid Bed Bioreactor performance is strongly affected by bed void fraction or bed porosity fluctuations. Particle size enlargement due to biofilm growth is an important factor that is involved in these variations and until now there are no mathematical equations that consider biofilm growth. In this work a mathematical equation is proposed to calculate bed void fraction in an inverse fluid bed bioreactor. (Author)

  9. Detection of fungi from rice black bug Paraeucosmetus pallicornis Dallas (Hemiptera: Lygaeidae) and inhibition with crude extract of Calatropis gigantea (Asclepiadaceae)

    Science.gov (United States)

    Sjam, S.; Surapati, U.; Adiwena; Syatri, A.; Dewi, V. S.; Rosmana, A.

    2018-05-01

    Rice black bug (P. palicornis) is one of the pests that attack the rice plants in the generative phase that causes the rice easily destroyed when milled and tasted bitter after cooking hence reduces the quality and quantity of rice. The bitter taste in rice may be due to the fungus associated with rice black bug. The aimed of this research was to detect the associated fungi with rice black bug P. pallicornis using some sterilization methods and inhibition with of leaf crude extract of C. gigatea. Detection of fungi from P. pallicornis was conducted using three sterilization methods and control (without sterilization) namely: (1) sterilization with aquades + alcohol 70% (5, 10, 15 and 20 times dipping) + aquades; (2) aquades + alcohol 70% (10 and 20 times dipping); (3) Aquades + alcohol 90 %+ NaCl 0.5 % +alcohol 90 % + aquades. Inhibition of fungi from P. pallicornis with crude extract of C. gigantea obtained by maceration method and then made some concentration to see the effect of its inhibition on the fungi associated with the P. pallicornis. The results showed that without sterilization, four microbe were obtained: Gliocladium sp., Aspergillus sp., black hyphae fungus and white hyphae fungus, sterilization method of Aquades + alcohol 70% with 5 times dipping in alcohol obtained Gliocladium sp., 10 and 20 times dipping found Aspergillus sp. and Gliocladium sp and 15 times dipping found Aspergillus sp. Sterilization with 10 and 20 times dipping in alcohol 70% then washing 2 times with aquades found Gliogladium sp. and Aspergillus sp. Sterilization with Aquades + alcohol 90 % + NaCl 0.5% + alcohol 90% + aquades found Gliocladium sp. Crude extract of C. gigantea had the potential to inhibit fungi Aspergillus sp. and Gliocladium sp. from rice black bug.

  10. An assessment of biological processes close to the sea bed in a slope region and its significance to the assessment of sea bed disposal of radioactive waste

    International Nuclear Information System (INIS)

    Hargreaves, P.M.; Ellis, C.J.; Angel, M.V.

    1984-01-01

    Vertical profiles of planktonic and micronektonic biomass observed close to the sea bed along a transect running up the continental slope on the southern flank of the Porcupine Seabight (to the southwest of Ireland) showed that a doubling in biomass concentration occurs from 100 to 10m above the sea bed. Comparison with biomass concentrations at two deep water stations, one in the Seabight and the other in the Rockall Trough, showed that there was a consistent increase in standing crop close to the sea bed over the slope. Supplementary data were collected on the northern flank of the Seabight. Analysis of both taxonomic groups and individual species showed that some taxa were more abundant near the sea floor and extended their vertical ranges to greater depths over the slope than over deep water, other taxa were unaffected. The implications to the problem of assessing the safety of sea bed disposal of high level radioactive waste are summarised. (author)

  11. A polytropic model of a critical two-phase flow in a bed of spherical particles

    Directory of Open Access Journals (Sweden)

    Tairov Emir

    2017-01-01

    Full Text Available The paper is concerned with a model of isenthalpic flow of vapor-water mixture in a fixed bed of solid particles. The mixture expansion process is considered to be polytropic. Similarly to the known problem of gas dynamics of a granular bed we obtained the relationships for calculation of a critical mass velocity. The results of the calculation based on a theoretical model are compared with the experimental data obtained in the packed beds of steel balls, 2 mm and 4 mm in diameter.

  12. Impact of Bug-in-Ear Professional Development on Early Childhood Co-Teachers' Use of Communication Strategies

    Science.gov (United States)

    Ottley, Jennifer R.; Grygas Coogle, Christan; Rahn, Naomi L.; Spear, Caitlin F.

    2017-01-01

    The goal of this study was to build the capacity of early childhood teachers to implement evidence-based strategies. We investigated the efficacy of professional development with bug-in-ear peer coaching in improving teachers' use of communication strategies, the teachers' maintenance of strategies post intervention, and the social validity of the…

  13. Characterization of TES bolometers used in 2-dimensional Backshort-Under-Grid (BUG) arrays for far-infrared astronomy

    International Nuclear Information System (INIS)

    Staguhn, J.G.; Allen, C.A.; Benford, D.J.; Chervenak, J.A.; Chuss, D.T.; Miller, T.M.; Moseley, S.H.; Wollack, E.J.

    2006-01-01

    We have produced a laboratory demonstration of our new Backshort-Under-Grid (BUG) bolometer array architecture in a monolithic, 2-dimensional, 8x8 format. The detector array is designed as a square grid of suspended, 1μm thick silicon bolometers with superconducting molybdium/gold bilayer TESs. These detectors use an additional layer of gold bars deposited on top of the bilayer, oriented transverse to the direction of the current flow, for the suppression of excess noise. This detector design has earlier been shown to provide near fundamental noise limited device performance. We present results from performance measurements of witness devices. In particular we demonstrate that the inband excess noise level of the TES detectors is less than 20% above the thermodynamic phonon noise limit and not significantly higher out of band at frequencies that cannot be attenuated by the Nyquist filter. Our 8x8 BUG arrays will be used in the near future for astronomical observations in several (sub-)millimeter instruments

  14. GCMS investigation of volatile compounds in green coffee affected by potato taste defect and the Antestia bug.

    Science.gov (United States)

    Jackels, Susan C; Marshall, Eric E; Omaiye, Angelica G; Gianan, Robert L; Lee, Fabrice T; Jackels, Charles F

    2014-10-22

    Potato taste defect (PTD) is a flavor defect in East African coffee associated with Antestiopsis orbitalis feeding and 3-isopropyl-2-methoxypyrazine (IPMP) in the coffee. To elucidate the manifestation of PTD, surface and interior volatile compounds of PTD and non-PTD green coffees were sampled by headspace solid phase microextraction and analyzed by gas chromatography mass spectrometry. Principal component analysis of the chromatographic data revealed a profile of surface volatiles distinguishing PTD from non-PTD coffees dominated by tridecane, dodecane, and tetradecane. While not detected in surface volatiles, IPMP was found in interior volatiles of PTD coffee. Desiccated antestia bugs were analyzed by GCMS, revealing that the three most prevalent volatiles were tridecane, dodecane, and tetradecane, as was found in the surface profile PTD coffee. Coffee having visible insect damage exhibited both a PTD surface volatile profile and IPMP in interior volatiles, supporting the hypothesis linking antestia bug feeding activity with PTD profile compounds on the surface and IPMP in the interior of the beans.

  15. Pebble-bed reactor

    International Nuclear Information System (INIS)

    Lohnert, G.; Mueller-Frank, U.; Heil, J.

    1976-01-01

    A pebble-bed nuclear reactor of large power rating comprises a container having a funnel-shaped bottom forming a pebble run-out having a centrally positioned outlet. A bed of downwardly-flowing substantially spherical nuclear fuel pebbles is positioned in the container and forms a reactive nuclear core maintained by feeding unused pebbles to the bed's top surface while used or burned-out pebbles run out and discharge through the outlet. A substantially conical body with its apex pointing upwardly and its periphery spaced from the periphery of the container spreads the bottom of the bed outwardly to provide an annular flow down the funnel-shaped bottom forming the runout, to the discharge outlet. This provides a largely constant downward velocity of the spheres throughout the diameter of the bed throughout a substantial portion of the down travel, so that all spheres reach about the same burned-out condition when they leave the core, after a single pass through the core area

  16. The Safety of Hospital Beds

    Science.gov (United States)

    Gervais, Pierre; Pooler, Charlotte; Merryweather, Andrew; Doig, Alexa K.; Bloswick, Donald

    2015-01-01

    To explore the safety of the standard and the low hospital bed, we report on a microanalysis of 15 patients’ ability to ingress, move about the bed, and egress. The 15 participants were purposefully selected with various disabilities. Bed conditions were randomized with side rails up or down and one low bed with side rails down. We explored the patients’ use of the side rails, bed height, ability to lift their legs onto the mattress, and ability to turn, egress, and walk back to the chair. The standard bed was too high for some participants, both for ingress and egress. Side rails were used by most participants when entering, turning in bed, and exiting. We recommend that side rails be reconsidered as a means to facilitate in-bed movement, ingress, and egress. Furthermore, single deck height settings for all patients are not optimal. Low beds as a safety measure must be re-evaluated. PMID:28462302

  17. Fluid-bed combustion

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, G.; Schoebotham, N.

    1981-02-01

    In Energy Equipment Company's two-stage fluidized bed system, partial combustion in a fluidized bed is followed by burn-off of the generated gases above the bed. The system can be retrofitted to existing boilers, and can burn small, high ash coal efficiently. It has advantages when used as a hot gas generator for process drying. Tests on a boiler at a Cadbury Schweppes plant are reported.

  18. Biodenitrification of gaseous diffusion plant aqueous wastes: stirred bed reactor

    International Nuclear Information System (INIS)

    Holland, M.E.

    1980-01-01

    Approximately 30 kilograms of nitrates per day are discarded in the raffinates (acid wastes) of the Portsmouth Gaseous Diffusion Plant's X-705 Uranium Recovery and Decontamination Facility. A biodenitrification process employing continuous-flow, stirred-bed reactors has been successfully used to remove nitrates from similar acid wastes at the Oak Ridge Y-12 Plant. Laboratory studies have been made at Portsmouth to characterize the X-705 raffinates and to test the stirred-bed biodenitrification process on such raffinates. Raffinates which had been previously characterized were pumped through continuous-flow, stirred-bed, laboratory-scale reactors. Tests were conducted over a period of 146 days and involved variations in composition, mixing requirements, and the fate of several metal ions in the raffinates. Tests results show that 20 weight percent nitrates were reduced to a target nitrate effluent concentration of 100 μg/ml with a 99.64 percent efficiency. However, the average denitrification rate achieved was only 33% of that demonstrated with the Y-12 stirred-bed system. These low rates were probably due to the toxic effects of heavy metal ions on the denitrifying bacteria. Also, most of the uranium in the raffinate feed remained in the biomass and calcite, which collected in the reactor. This could cause criticality problems. For these reasons, it was decided not to make use of the stirred-bed bioreactor at Portsmouth. Instead, the biodenitrification installation now planned will use fluidized bed columns whose performance will be the subject of a subsequent report

  19. BIOLOGICAL CHARACTERISTICS OF PRUSSIAN CARP (CARASSIUS AURATUS GIBELIO (BLOCH, 1782 COMMERCIAL STOCK OF THE DNIEPER-BUG ESTUARY

    Directory of Open Access Journals (Sweden)

    К. Heina

    2017-09-01

    Full Text Available Purpose. To provide the biological assessment of the silver Prussian carp (Carassius auratus gibelio (Bloch, 1782 commercial stock of the Dnieper-Bug estuary in the conditions of the transformed Dnieper river flow. Methodology. During the analysis of the biological state of the Prussian carp commercial stock, the main attention was given to the dynamics of age and sexual structure, length-weight growth rate, absolute fecundity and condition factor. The basic data were collected during the work of control-observation stations of the Institute of Fisheries in the Dnieper-Bug estuary during the current century. The collection and processing of ichthyological materials were performed in accordance with the generally accepted methodologies. Findings. The analysis showed that during the current century, the age structure of the Prussian carp of the Dnieper-Bug estuary was the most labile among other commercial cyprinids. It was found that as a result of an increase in the right wing of the age series, there was a gradual increase of the mean weighted age of its commercial stock. At the beginning of studies (2001-2002, the core of the stock was formed by age-3-6 fish (up ; however in subsequent years, a displacement of dominant groups toward the dominance of age-4-7 fish (more than 80% of the total stock was observed. At the same time, the relative number of age-3 fish (recruits was at a relatively high level – up to 10.6%. The linear growth varied more intensively until the age-5, but it reduced with ageing and did not show high variability. The body weight most variable was in age-4 fish (Cv=9.62%. The noted insignificant deviations in the body weight growth rate of the right wing of the age series was due to stable predominance of females in the stock structure, which were characterized by a variability of the mean weight as a result of different development of gonads. The dynamics of the age-related changes in the condition factor indicated on a

  20. Commercial-biological characteristics of tulka (Clupeonella cultriventris Nordmann, 1840 of the Dnieper-Bug estuary system

    Directory of Open Access Journals (Sweden)

    K. Geina

    2017-12-01

    Full Text Available Purpose. To give biological assessment of the commercial stock of tulka Clupeonella cultriventris (Nordmann, 1840 of the Dnieper-Bug estuary system in the conditions of the reduced Dnieper flow. Methodology. Analysis of the biological state of the tulka stock of the Dnieper-Bug estuary system was performed based on the data on the dynamics of its age structure, linear-weight growth and condition factor. Primary materials were obtained from scientific and commercial catches done during the current century. Field and laboratory processing of the ichthyological materials were performed according to generally accepted methods. Findings. Current commercial fishery situation in the Dnieper-Bug estuary system is characterized by reduced intensity of tulka harvest. Currently, major fish harvest is concentrated in the Mykolaiv fishing ground. As a result of continuous underfishing, a gradual growth of the mean weighed age of the tulka stock is observed with the accumulation of maximum groups of the right wing of the age series. At the beginning of the study (2001-2004, when age group was represented by three groups, the nucleus of the population was formed by age-1 and age-2 fish – 95.7%. However, last years, due to an increase in the number of age-4 fish, a reduction in the percentage of modal groups (age-1 and ahe-2 fish to 76.7% was observed. At the same time, the share of age-3 and age-4 fish gradually increased from 15.8% in 2013 to 23.2% in 2017. Against the background of a relatively instable age structure, the linear growth and body weight growth rates did not change significantly. The highest variability of linear parameters was observed in age-1 fish. With a mean body length of 40.55±0.53 mm (lim=36.2-45.2 mm, deviations from the modal value (Cv were 5.10%. With an increase in the age, the linear growth rate decreased and no significant variability was observed. The highest variability of body weight was typical for age-1 and age-2 fish (Cv

  1. Supporting Early Childhood Educators' Use of Embedded Communication Strategies by Providing Feedback via Bug-in-Ear Technology

    Science.gov (United States)

    Riggie, Jennifer

    2013-01-01

    The purpose of this study was to examine the relationship between coaching provided with bug-in-ear technology, the frequency of the early childhood educators' use of targeted communication strategies and children's expressive communication. Four multiple-baseline single-case design experiments were completed to evaluate these relationships.…

  2. Apparatus for controlling fluidized beds

    Science.gov (United States)

    Rehmat, A.G.; Patel, J.G.

    1987-05-12

    An apparatus and process are disclosed for control and maintenance of fluidized beds under non-steady state conditions. An ash removal conduit is provided for removing solid particulates from a fluidized bed separate from an ash discharge conduit in the lower portion of the grate supporting such a bed. The apparatus and process of this invention is particularly suitable for use in ash agglomerating fluidized beds and provides control of the fluidized bed before ash agglomeration is initiated and during upset conditions resulting in stable, sinter-free fluidized bed maintenance. 2 figs.

  3. An Evaluation of Reed Bed Technology to Dewater Army Wastewater Treatment Plant Sludge

    Science.gov (United States)

    1993-09-01

    speculated that the plants produced "root exudations" that were active against pathogens , and that the plants specifically showed an affinity for cadmium, zinc...mineralize and for pathogens to be destroyed. This downtime makes multiple beds necessary. The USEPA also reports that the major advantage of the reed...employee to regulate the sludge applications. This employee would also visually assess the beds for possible problems such as weed or insect ( aphid

  4. The importance of gut symbionts in the development of the brown marmorated stink bug, Halyomorpha halys (Stål.

    Directory of Open Access Journals (Sweden)

    Christopher M Taylor

    Full Text Available The invasive brown marmorated stink bug, Halyomorpha halys (Stål, has become a severe agricultural pest and nuisance problem since its introduction in the U.S. Research is being conducted to understand its biology and to find management solutions. Its symbiotic relationship with gut symbionts is one aspect of its biology that is not understood. In the family Pentatomidae, the reliance on gut symbionts for successful development seems to vary depending on the species of stink bug. This research assessed the role of gut symbionts in the development, survivorship, and fecundity of H. halys. We compared various fitness parameters of nymphs and adults reared from surface sterilized and untreated egg masses during two consecutive generations under laboratory conditions. Results provided direct evidence that H. halys is negatively impacted by the prevention of vertical transmission of its gut symbionts and that this impact is significant in the first generation and manifests dramatically in the subsequent generation. Developmental time and survivorship of treated cohorts in the first generation were significantly affected during third instar development through to the adult stage. Adults from the sterilized treatment group exhibited longer pre-oviposition periods, produced fewer egg masses, had significantly smaller clutch sizes, and the hatch rate and survivorship of those eggs were significantly reduced. Observations following hatch of surface sterilized eggs also revealed significant effects on wandering behavior of the first instars. The second generation progeny from adults of the sterilized cohorts showed significantly lower survival to adulthood, averaging only 0.3% compared to 20.8% for the control cohorts. Taken together, results demonstrate that H. halys is heavily impacted by deprival of its gut symbionts. Given the economic status of this invasive pest, further investigations may lead to management tactics that disrupt this close symbiotic

  5. Managing Vegetation on Peat-Sand Filter Beds for Wastewater Disposal

    Science.gov (United States)

    Arthur E. Elling

    1985-01-01

    Five species of grass, one sedge, and cattail were grown on a peat-sand filter bed irrigated with sewage effluent. Yields, uptake of nitrogen and phosphorus, and lodging problems were determined for all species when grown to various heights ranging from 5 to 75 cm.

  6. Retrofit design of rice husk feeding system in the production of amorphous silica ash in a pilot scale fluidized bed combustor

    International Nuclear Information System (INIS)

    Abdul, A.; Rozainee, M.; Anwar, J.; Wan Alwi, R.S.

    2010-01-01

    Full text: Rice husk is among the most important recovery resources for silica that is produced annually in huge quantities in many countries such as Malaysia which produces 2.38 (MT) of rice paddy. Rice husks accounts for 14-35 % of the weight of the paddy harvested, depending on the paddy variety and because of its abundance it poses serious environmental problems in the rice producing countries. Therefore, the thermo-chemical conversion of rice husks to useful silica ash by fluidized bed combustion is the proven and cost-effective technology for converting the renewable waste husks by making commercial use of this rice husk ash because of its self sustaining ability. However, feeding of rice husk into the reactor bed has become a difficult problem hindering the production of amorphous silica. This is due to the poor penetration and low bulk density as well as the flaky, abrasive and joined nature of rice husk. Most of the researches into fluidized bed combustion are on laboratory or bench scale and none had discussed pilot scale combustion of rice husk into amorphous silica. A recent attempt to solve this feeding problem from an experimental investigation in a bench-scale culminates into a pilot-scale fluidized bed combustor designed with a combined screw conveyor and an inclined pneumatic feeding by direct injection, yet the problem persists. This paper presents a retrofit design of the existing 0.5 m internal diameter pilot scale fluidized bed combustor by the use of combined screw feeding system. It is envisaged that at the end of the experimental investigation the retrofit design will address the problem associated with rice husk feeding in bubbling fluidized bed combustors. (author)

  7. Experimental study of flow field characteristics on bed configurations in the pebble bed reactor

    International Nuclear Information System (INIS)

    Jia, Xinlong; Gui, Nan; Yang, Xingtuan; Tu, Jiyuan; Jia, Haijun; Jiang, Shengyao

    2017-01-01

    Highlights: • PTV study of flow fields of pebble bed reactor with different configurations are carried out. • Some criteria are proposed to quantify vertical velocity field and flow uniformity. • The effect of different pebble bed configurations is also compared by the proposed criteria. • The displacement thickness is used analogically to analyze flow field characteristics. • The effect of mass flow variation in the stagnated region of the funnel flow is measured. - Abstract: The flow field characteristics are of fundamental importance in the design work of the pebble bed high temperature gas cooled reactor (HTGR). The different effects of bed configurations on the flow characteristics of pebble bed are studied through the PTV (Particle Tracking Velocimetry) experiment. Some criteria, e.g. flow uniformity (σ) and mass flow level (α), are proposed to estimate vertical velocity field and compare the bed configurations. The distribution of the Δθ (angle difference between the individual particle velocity and the velocity vector sum of all particles) is also used to estimate the resultant motion consistency level. Moreover, for each bed configuration, the thickness of displacement is analyzed to measure the effect of the funnel flow zone based on the boundary layer theory. Detailed information shows the quantified characteristics of bed configuration effects on flow uniformity and other characteristics; and the sequence of levels of each estimation criterion is obtained for all bed configurations. In addition, a good design of the pebble bed configuration is suggested and these estimation criteria can be also applied and adopted in testing other geometry designs of pebble bed.

  8. Bed diameter effects and incipient slugging in gas fluidized beds

    International Nuclear Information System (INIS)

    Agarwal, P.K.

    1986-01-01

    The coalescence and growth of bubble swarms formed at the distributor of a fluidized bed gives rise to lateral as well as vertical distributions of bubble properties. However, existing models employ average bubble properties obtained largely from semi-empirical considerations. In a recent Paper, the author developed a bubble growth model based on a population balance approach. Analytical expressions were derived for the bubble characteristic distributions and averages. However, the model, developed for unconstrained growth, did not take into account the effect of the bed diameter and the possibility of slugging. In this Paper, the model is extended to take these aspects into account. A slugging criterion is also developed which is expected to be valid for the regime where incipient slugging depends on the bed height as well as the region where bed height does not significantly affect minimum slugging conditions

  9. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... Use bed nets. If sleeping in the great outdoors, use bed nets to protect against mosquitoes. Look ... c Explore the Academy Member resources Practice Tools Education Meetings & events Advocacy Public & patients Academy resources for: ...

  10. Optimization Model for Capacity Management and Bed Scheduling for Hospital

    Science.gov (United States)

    Sitepu, Suryati; Mawengkang, Herman; Husein, Ismail

    2018-01-01

    Hospital is a very important institution to provide health care for people. It is not surprising that nowadays the people’s demands for hospital is increasing.. However, due to the rising cost of healthcare services, hospitals need to consider efficiencies in order to overcome these two problems. This paper deals with an integrated strategy of staff capacity management and bed allocation planning to tackle these problems. Mathematically, the strategy can be modeled as an integer linear programming problem. We solve the model using a direct neighborhood search approach, based on the notion of superbasic variables.

  11. Particulate Matter (PM) Pollution

    Science.gov (United States)

    ... Bed Bugs Chemicals and Toxics Environmental Information by Location Greener Living Health Land, Waste, and Cleanup Lead Mold Pesticides Radon Science Water A-Z Index Laws & Regulations By Business Sector By Topic Compliance Enforcement Laws and Executive ...

  12. Maladaptive Plasticity Masks the Effects of Natural Selection in the Red-Shouldered Soapberry Bug.

    Science.gov (United States)

    Cenzer, Meredith L

    2017-10-01

    Natural selection can produce local adaptation, but local adaptation can be masked by maladaptive plasticity. Maladaptive plasticity may arise as a result of gene flow producing novel gene combinations that have not been exposed to selection. In the 1980s, populations of the red-shouldered soapberry bug (Jadera haematoloma) were locally adapted to feed on the seeds of a native host plant and an introduced host plant; by 2014, local differentiation in beak length had been lost, likely as a consequence of increased gene flow. In this study, I assess the relative contributions of natural selection and plasticity to beak length on these two hosts. I confirm the earlier hypothesis that the host plant seedpod drives divergent natural selection on beak length. I then demonstrate that the proximate cause of the loss of observable differentiation in beak length is maladaptive plasticity, which masks persistent genetic differences between host-associated populations. Maladaptive plasticity is highest in areas where the two plants co-occur; in combination with historical measures of plasticity in hybrids, this indicates that maladaptive plasticity may be a consequence of ongoing gene flow. Although natural selection produced locally adapted genotypes in soapberry bugs, maladaptive plasticity is masking phenotypic differences between populations in nature.

  13. Effect of bed configuration on pebble flow uniformity and stagnation in the pebble bed reactor

    International Nuclear Information System (INIS)

    Gui, Nan; Yang, Xingtuan; Tu, Jiyuan; Jiang, Shengyao

    2014-01-01

    Highlights: • Pebble flow uniformity and stagnation characteristics are very important for HTR-PM. • Arc- and brachistochrone-shaped configuration effects are studied by DEM simulation. • Best bed configurations with uniform flow and no stagnated pebbles are suggested. • Detailed quantified characteristics of bed configuration effects are shown for explanation. - Abstract: Pebble flow uniformity and stagnation characteristics are very important for the design of pebble bed high temperature gas-cooled reactor. Pebble flows inside some specifically designed contraction configurations of pebble bed are studied by discrete element method. The results show the characteristics of stagnation rates, recycling rates, radial distribution of pebble velocity and residence time. It is demonstrated clearly that the bed with a brachistochrone-shaped configuration achieves optimum levels of flow uniformity and recycling rate concentration, and almost no pebbles are stagnated in the bed. Moreover, the optimum choice among the arc-shaped bed configurations is demonstrated too. Detailed information shows the quantified characteristics of bed configuration effects on flow uniformity. In addition, a good design of the pebble bed configuration is suggested

  14. Improvement for the design of packed moving bed adsorption column

    International Nuclear Information System (INIS)

    Xiao Wei

    2014-01-01

    The problems needed to pay attention to in the physical design of packed moving bed adsorption column were presented. The design of key parts such as the inlet and outlet of liquid phase and gas phase were improved. The expected effect was achieved by the improvement. (author)

  15. Visualization of bed material movement in a simulated fluidized bed heat exchanger by neutron radiography

    International Nuclear Information System (INIS)

    Umekawa, Hisashi; Ozawa, Mamoru; Takenaka, Nobuyuki; Matsubayashi, Masahito

    1999-01-01

    The bulk movement of fluidized bed material was visualized by neutron radiography by introducing tracers into the bed materials. The simulated fluidized bed consisted of aluminum plates, and the bed material was sand of 99.7% SiO 2 (mean diameter: 0.218 mm, density: 2555 kg/m 3 ). Both materials were almost transparent to neutrons. Then the sand was colored by the contamination of the sand coated by CdSO 4 . Tracer particles of about 2 mm diameter were made by the B 4 C, bonded by the vinyl resin. The tracer was about ten times as large as the particle of fluidized bed material, but the traceability was enough to observe the bed-material bulk movement owing to the large effective viscosity of the fluidized bed. The visualized images indicated that the bubbles and/or wakes were important mechanism of the behavior of the fluidized bed movement

  16. Method and apparatus for a combination moving bed thermal treatment reactor and moving bed filter

    Energy Technology Data Exchange (ETDEWEB)

    Badger, Phillip C.; Dunn, Jr., Kenneth J.

    2015-09-01

    A moving bed gasification/thermal treatment reactor includes a geometry in which moving bed reactor particles serve as both a moving bed filter and a heat carrier to provide thermal energy for thermal treatment reactions, such that the moving bed filter and the heat carrier are one and the same to remove solid particulates or droplets generated by thermal treatment processes or injected into the moving bed filter from other sources.

  17. Predicting the distribution of bed material accumulation using river network sediment budgets

    Science.gov (United States)

    Wilkinson, Scott N.; Prosser, Ian P.; Hughes, Andrew O.

    2006-10-01

    Assessing the spatial distribution of bed material accumulation in river networks is important for determining the impacts of erosion on downstream channel form and habitat and for planning erosion and sediment management. A model that constructs spatially distributed budgets of bed material sediment is developed to predict the locations of accumulation following land use change. For each link in the river network, GIS algorithms are used to predict bed material supply from gullies, river banks, and upstream tributaries and to compare total supply with transport capacity. The model is tested in the 29,000 km2 Murrumbidgee River catchment in southeast Australia. It correctly predicts the presence or absence of accumulation in 71% of river links, which is significantly better performance than previous models, which do not account for spatial variability in sediment supply and transport capacity. Representing transient sediment storage is important for predicting smaller accumulations. Bed material accumulation is predicted in 25% of the river network, indicating its importance as an environmental problem in Australia.

  18. Propagation of a Strong Shock Over a Random Bed of Spherical Particles

    Energy Technology Data Exchange (ETDEWEB)

    Mehta, Y. [Univ. of Florida, Gainesville, FL (United States); Neal, C. [Univ. of Florida, Gainesville, FL (United States); Salari, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Jackson, T. L. [Univ. of Florida, Gainesville, FL (United States); Balachandar, S. [Univ. of Florida, Gainesville, FL (United States); Thakur, S. [Univ. of Florida, Gainesville, FL (United States)

    2017-04-11

    Propagation of a strong shock through a bed of particles results in complex wave dynamics such as a reflected shock, a transmitted shock, and highly unsteady flow inside the particle bed. In this paper we present three-dimensional numerical simulations of shock propagation in air over a random bed of particles. We assume the flow is inviscid and governed by the Euler equations of gas dynamics. Simulations are carried out by varying the volume fraction of the particle bed at a fixed shock Mach number. We compute the unsteady inviscid streamwise and transverse drag coefficients as a function of time for each particle in the random bed as a function of volume fraction. We show that (i) there are significant variations in the peak drag for the particles in the bed, (ii) the mean peak drag as a function of streamwise distance through the bed decreases with a slope that increases as the volume fraction increases, and (iii) the deviation from the mean peak drag does not correlate with local volume fraction. We also present the local Mach number and pressure contours for the different volume fractions to explain the various observed complex physical mechanisms occurring during the shock-particle interactions. Since the shock interaction with the random bed of particles leads to transmitted and reflected waves, we compute the average flow properties to characterize the strength of the transmitted and reflected shock waves and quantify the energy dissipation inside the particle bed. Finally, to better understand the complex wave dynamics in a random bed, we consider a simpler approximation of a planar shock propagating in a duct with a sudden area change. We obtain Riemann solutions to this problem, which are used to compare with fully resolved numerical simulations.

  19. Fluidised bed combustion system

    International Nuclear Information System (INIS)

    McKenzie, E.C.

    1976-01-01

    Fluidized bed combustion systems that facilitates the maintenance of the depth of the bed are described. A discharge pipe projects upwardly into the bed so that bed material can flow into its upper end and escape downwardly. The end of the pipe is surrounded by an enclosure and air is discharged into the enclosure so that material will enter the pipe from within the enclosure and have been cooled in the enclosure by the air discharged into it. The walls of the enclosure may themselves be cooled

  20. Attempts on cardoon gasification in two different circulating fluidized beds

    Directory of Open Access Journals (Sweden)

    Chr. Christodoulou

    2014-11-01

    Full Text Available Few tests have been carried out in order to evaluate the use of cardoon in gasification and combustion applications most of the researchers dealt with agglomeration problems. The aim of this work is to deal with the agglomeration problem and to present a solution for the utilization of this biofuel at a near industrial application scale. For this reason, two experiments were conducted, one in TU Delft and one in Centre for Research and Technology Hellas (CERTH, using fuel cardoon and 50% w/w cardoon blended with 50% w/w giant reed respectively. Both experimental campaigns were carried out in similar atmospheric circulating fluidized bed gasifiers. Apart from the feedstock, the other differences were the gasification medium and the bed material used in each trial. The oxidizing agent at TUD׳s run was O2/steam, whereas CERTH׳s tests used air. When experiments with the cardoon 50% w/w–giant reed 50% w/w blend were performed no agglomeration problems were presented. Consequently, gasification could be achieved in higher temperature than that of pure cardoon which led to the reduction of tar concentration.

  1. WTP Pretreatment Facility Potential Design Deficiencies--Sliding Bed and Sliding Bed Erosion Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, E. K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-05-06

    This assessment is based on readily available literature and discusses both Newtonian and non-Newtonian slurries with respect to sliding beds and erosion due to sliding beds. This report does not quantify the size of the sliding beds or erosion rates due to sliding beds, but only assesses if they could be present. This assessment addresses process pipelines in the Pretreatment (PT) facility and the high level waste (HLW) transfer lines leaving the PT facility to the HLW vitrification facility concentrate receipt vessel.

  2. WTP Pretreatment Facility Potential Design Deficiencies--Sliding Bed and Sliding Bed Erosion Assessment

    International Nuclear Information System (INIS)

    Hansen, E. K.

    2015-01-01

    This assessment is based on readily available literature and discusses both Newtonian and non-Newtonian slurries with respect to sliding beds and erosion due to sliding beds. This report does not quantify the size of the sliding beds or erosion rates due to sliding beds, but only assesses if they could be present. This assessment addresses process pipelines in the Pretreatment (PT) facility and the high level waste (HLW) transfer lines leaving the PT facility to the HLW vitrification facility concentrate receipt vessel.

  3. Bacillus cereus in free-stall bedding.

    Science.gov (United States)

    Magnusson, M; Svensson, B; Kolstrup, C; Christiansson, A

    2007-12-01

    To increase the understanding of how different factors affect the bacterial growth in deep sawdust beds for dairy cattle, the microbiological status of Bacillus cereus and coliforms in deep sawdust-bedded free stalls was investigated over two 14-d periods on one farm. High counts of B. cereus and coliforms were found in the entire beds. On average, 4.1 log(10) B. cereus spores, 5.5 log(10) B. cereus, and 6.7 log(10) coliforms per gram of bedding could be found in the upper layers of the sawdust likely to be in contact with the cows' udders. The highest counts of B. cereus spores, B. cereus, and coliforms were found in the bedding before fresh bedding was added, and the lowest immediately afterwards. Different factors of importance for the growth of B. cereus in the bedding material were explored in laboratory tests. These were found to be the type of bedding, pH, and the type and availability of nutrients. Alternative bedding material such as peat and mixtures of peat and sawdust inhibited the bacterial growth of B. cereus. The extent of growth of B. cereus in the sawdust was increased in a dose-dependent manner by the availability of feces. Urine added to different bedding material raised the pH and also led to bacterial growth of B. cereus in the peat. In sawdust, a dry matter content greater than 70% was needed to lower the water activity to 0.95, which is needed to inhibit the growth of B. cereus. In an attempt to reduce the bacterial growth of B. cereus and coliforms in deep sawdust beds on the farm, the effect of giving bedding daily or a full replacement of the beds was studied. The spore count of B. cereus in the back part of the free stalls before fresh bedding was added was 0.9 log units lower in stalls given daily bedding than in stalls given bedding twice weekly. No effect on coliform counts was found. Replacement of the entire sawdust bedding had an effect for a short period, but by 1 to 2 mo after replacement, the counts of B. cereus spores in the

  4. Astronomical cycle origin of bedded chert: A middle Triassic bedded chert sequence, Inuyama, Japan

    Science.gov (United States)

    Ikeda, Masayuki; Tada, Ryuji; Sakuma, Hironobu

    2010-09-01

    Astronomical forcing is one of the main drivers of climate change, and astronomical cyclicity recorded in sediments provides a clue to understand the dynamics of the global climate system. Bedded cherts consist of rhythmic alternations of chert and shale beds. Although previous studies have hypothesized that the origin of bedded chert is related to astronomical cycles (e.g. Fischer, 1976; Hori et al., 1993), conclusive proof remains elusive. To explore this possibility, we established a continuous, high-resolution lithostratigraphy of middle Triassic bedded chert in Central Japan. The average duration of each chert-shale couplet is 20 kyr, similar to that of the precession cycle. Spectral analysis of a bed number series of thickness variations in chert beds was performed assuming that each chert-shale couplet represents a 20-kyr precession cycle. The results reveal cycles involving approximately 200, 20, 5, and 2-3 beds, corresponding to periodicities of approximately 4000, 400, 100, and 40-60 kyr, respectively. By further assuming that the 20-bed cycle represents a 405-kyr eccentricity cycle of constant and stable periodicity, we converted the bed number series to a time series. Spectral analysis of the time series revealed distinct periodicities of 3600, 117, 97, and 38 kyr, in addition to 405 kyr. Besides 3600 kyr, these periodicities agree well with the 120, 95, and 37 kyr periodicities for eccentricity cycles and the obliquity cycle during the Triassic. Moreover, we detected amplitude modulation of the approximately 100-kyr cycle of thickness variations in chert beds with a 405-kyr periodicity, which may correspond to amplitude modulation of 100-kyr climatic precession cycle with the 405-kyr periodicity. The approximately 3600-kyr periodicity described above and 1800-kyr periodicity manifested as the amplitude modulation of the 405-kyr cycle are correlated to present-day long-term eccentricity cycles of 2400 and 4800 kyr evolved by chaotic behavior of solar

  5. Coating and melt induced agglomeration in a poultry litter fired fluidized bed combustor

    International Nuclear Information System (INIS)

    Billen, Pieter; Creemers, Benji; Costa, José; Van Caneghem, Jo; Vandecasteele, Carlo

    2014-01-01

    The combustion of poultry litter, which is rich in phosphorus, in a fluidized bed combustor (FBC) is associated with agglomeration problems, which can lead to bed defluidization and consequent shutdown of the installation. Whereas earlier research indicated coating induced agglomeration as the dominant mechanism for bed material agglomeration, it is shown experimentally in this paper that both coating and melt induced agglomeration occur. Coating induced agglomeration mainly takes place at the walls of the FBC, in the freeboard above the fluidized bed, where at the prevailing temperature the bed particles are partially molten and hence agglomerate. In the ash, P 2 O 5 forms together with CaO thermodynamically stable Ca 3 (PO 4 ) 2 , thus reducing the amount of calcium silicates in the ash. This results in K/Ca silicate mixtures with lower melting points. On the other hand, in-bed agglomeration is caused by thermodynamically unstable, low melting HPO 4 2− and H 2 PO 4 − salts present in the fuel. In the hot FBC these salts may melt, may cause bed particles to stick together and may subsequently react with Ca salts from the bed ash, forming a solid bridge of the stable Ca 3 (PO 4 ) 2 between multiple particles. - Highlights: • Coating induced agglomeration not due to K phosphates, but due to K silicates. • Melt induced agglomeration due to H 2 PO 4 − and HPO 4 2− salts in the fuel. • Wall agglomeration corresponds to coating induced mechanism. • In-bed agglomeration corresponds to melt induced mechanism

  6. Characterizing Damage of Brown Marmorated Stink Bug (Hemiptera: Pentatomidae) in Blueberries.

    Science.gov (United States)

    Wiman, Nik G; Parker, Joyce E; Rodriguez-Saona, Cesar; Walton, Vaughn M

    2015-06-01

    Brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is a severe economic pest of growing importance in the United States, Canada, and Europe. While feeding damage from H. halys has been characterized in tree fruit, vegetables, and agronomic crops, less is known about the impacts of stink bugs on small fruits such as blueberries. In this study, we examined H. halys feeding on two representative early and late ripening blueberry cultivars in Oregon and New Jersey. This research examined how different densities of H. halys confined on blueberry clusters for week-long periods affected fruit quality at harvest. After fruit were ripe, we stained and quantified the number of salivary sheaths on berries as an indication of feeding pressure. Feeding by H. halys damaged the fruits by causing increased levels of external discoloration, and internal damage in the form of tissue necrosis. Exposure of berries to H. halys was also associated with decreasing berry weights and lower soluble solids in fruits. However, the different cultivars did not respond consistently to feeding pressure from H. halys. Weekly variability in feeding pressure of two of the cultivars as quantified by the number of stylet sheaths per berry was largely accounted for by environmental variables. We conclude that H. halys does have potential to severely damage blueberries and may become an important economic pest. Characterization of damage is important because correct identification of insect damage is key for successful management. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Thermofluid-neutronic stability of the rotating, fluidized bed, space-power reactor

    International Nuclear Information System (INIS)

    Lee, C.C.; Jones, O.C.; Becker, M.

    1993-01-01

    A rotating fluidized bed nuclear reactor has the potential of being a vary attractive option for ultra-high power space systems, especially for propulsion. Research has already examined fuel bed expansion due to variations in state variables, propellant flow rate, and rotational speed, and has also considered problems related to thermal stress. This paper describes the results of a coupled thermofluid-neutronic analysis where perturbations in fuel bed height caused by maneuvering changes in operating conditions alter power levels due to varying absorption of neutrons which would otherwise leak from the system, mainly through the nozzle. This first analysis was not a detailed stability analysis. Rather, it utilized simplified neutronic methods, and was intended to provide an order-of-magnitude assessment of the stability of the reactor with the intention to determine whether or not stability might be a 'concept killer'. Stability was compared with a fixed-fuel-bed reactor of identical geometry for three different cases comprising a set of small, medium and large sizes/powers from 250 MW to 5 GW. It was found that power fluctuations in the fluidized bed reactor were larger by 100 db or more than expected in a packed bed reactor of the same geometry, but never resulted in power excursions. Margins to unit gain in some cases, however, were sufficiently small that the approximations in this quasi-2-dimensional model may not be sufficiently accurate to preclude significant excursions. (orig.)

  8. Dissolved oxygen control in a coupled fluidized bed system

    International Nuclear Information System (INIS)

    Jones, R.M.; Melcer, H.

    1988-01-01

    The biological fluidized bed process is a modification of more conventional fixed film processes, such as the trickling filter, in which wastewater is passed upward through a bed of granular support medium, typically sand, at a sufficient velocity to expand or fluidize the medium. The granular medium provides a large surface area for the establishment of a biological film. The fluidized bed process was selected to investigate the treatment of coking plant wastewaters in view of the significant advantages offered in terms of reduced reactor volumes that result from the high biomass concentration maintained on the support medium. The technical feasibility of treating coal distillation condensates was evaluated during a 3-year study at Environment Canada's Wastewater Technology Centre (WTC). The feed to the pilot scale test system consisted of effluent from fixed and free leg ammonia stills at the by-product coke plant of Dofasco Inc. in Hamilton, Ontario. The pilot plant consisted of two fluidized bed reactors in series, coupled to provide carbon oxidation, nitrification and denitrification in the predenitrification operating mode. The anoxic denitrification reactor was 115 mm in diameter and the oxygenic nitrification reactor, 290 mm in diameter. The bed heights and reactor volumes were adjustable by relocation of the position of the sand/biomass wasting valve. The experimental objective of this research was to determine those operating conditions required to maintain stable nitrification and complete denitrification under both steady state and dynamic operating conditions. Details regarding operating, sampling and analytic procedures have been presented elsewhere. A specific operating problem existed relating to the control of the dissolved oxygen concentration in the oxygenic fluidized bed reactor, the solution of which forms the basis of the paper

  9. Application of CaO-Based Bed Material for Dual Fluidized Bed Steam Biomass Gasification

    Science.gov (United States)

    Koppatz, S.; Pfeifer, C.; Kreuzeder, A.; Soukup, G.; Hofbauer, H.

    Gasification of biomass is a suitable option for decentralized energy supply based on renewable sources in the range of up to 50 MW fuel input. The paper presents the dual fluidized bed (DFB) steam gasification process, which is applied to generate high quality and nitrogen-free product gas. Essential part of the DFB process is the bed material used in the fluidized reactors, which has significant impact on the product gas quality. By the use of catalytically active bed materials the performance of the overall process is increased, since the bed material favors reactions of the steam gasification. In particular, tar reforming reactions are favored. Within the paper, the pilot plant based on the DFB process with 100kW fuel input at Vienna University of Technology, Austria is presented. Actual investigations with focus on CaO-based bed materials (limestone) as well as with natural olivine as bed material were carried out at the pilot plant. The application of CaO-based bed material shows mainly decreased tar content in the product gas in contrast to experiments with olivine as bed material. The paper presents the results of steam gasification experiments with limestone and olivine, whereby the product gas composition as well as the tar content and the tar composition are outlined.

  10. Novel adipokinetic hormones in the kissing bugs Rhodnius prolixus, Triatoma infestans, Dipetalogaster maxima and Panstrongylus megistrus

    Czech Academy of Sciences Publication Activity Database

    Marco, H. G.; Šimek, Petr; Clark, K. D.; Gäde, G.

    2013-01-01

    Roč. 41, MAR 10 (2013), s. 21-30 ISSN 0196-9781 R&D Projects: GA MZd(CZ) NT11513 Grant - others:National Research Foundation(ZA) IFR 2008071500048; National Research Foundation(ZA) FA 2007021300002 Institutional support: RVO:60077344 Keywords : insects * kissing bugs * reduviidae Subject RIV: ED - Physiology Impact factor: 2.614, year: 2013 http://www.sciencedirect.com/science/article/pii/S0196978112004433

  11. Building-Up of a DNA Barcode Library for True Bugs (Insecta: Hemiptera: Heteroptera) of Germany Reveals Taxonomic Uncertainties and Surprises

    Science.gov (United States)

    Raupach, Michael J.; Hendrich, Lars; Küchler, Stefan M.; Deister, Fabian; Morinière, Jérome; Gossner, Martin M.

    2014-01-01

    During the last few years, DNA barcoding has become an efficient method for the identification of species. In the case of insects, most published DNA barcoding studies focus on species of the Ephemeroptera, Trichoptera, Hymenoptera and especially Lepidoptera. In this study we test the efficiency of DNA barcoding for true bugs (Hemiptera: Heteroptera), an ecological and economical highly important as well as morphologically diverse insect taxon. As part of our study we analyzed DNA barcodes for 1742 specimens of 457 species, comprising 39 families of the Heteroptera. We found low nucleotide distances with a minimum pairwise K2P distance 2.2% were detected for 16 traditionally recognized and valid species. With a successful identification rate of 91.5% (418 species) our study emphasizes the use of DNA barcodes for the identification of true bugs and represents an important step in building-up a comprehensive barcode library for true bugs in Germany and Central Europe as well. Our study also highlights the urgent necessity of taxonomic revisions for various taxa of the Heteroptera, with a special focus on various species of the Miridae. In this context we found evidence for on-going hybridization events within various taxonomically challenging genera (e.g. Nabis Latreille, 1802 (Nabidae), Lygus Hahn, 1833 (Miridae), Phytocoris Fallén, 1814 (Miridae)) as well as the putative existence of cryptic species (e.g. Aneurus avenius (Duffour, 1833) (Aradidae) or Orius niger (Wolff, 1811) (Anthocoridae)). PMID:25203616

  12. Monitoring of brown stink bug (Hemiptera: Pentatomidae) population dynamics in corn to predict its abundance using weather data

    Science.gov (United States)

    The brown stink bug (BSB), Euschistus servus (Say) (Hemiptera: Pentatomidae), is a serious economic pest of corn production in the Southeastern U. S. The BSB population dynamics was monitored for 17 wks from tasseling to pre-harvest of corn plants (i.e., late May to mid-September) using pheromone ...

  13. Verde plant bug (Hemiptera: Miridae) feeding injury to cotton bolls charcterized by boll age, size and damage ratings

    Science.gov (United States)

    Our studies over 2 years (2009 and 2010) and 2 locations (Weslaco and Corpus Christi, TX) investigated the relationship of feeding-injury of the verde plant bug, Creontiades signatus Distant, to a range of cotton boll age classes further defined by boll diameter and accumulated degree-days (anthesis...

  14. Biodegradation of phenolic waste liquors in stirred-tank, packed-bed, and fluidized-bed bioreactors

    Energy Technology Data Exchange (ETDEWEB)

    Holladay, D W; Hancher, G W; Chilcote, D D; Scott, C D

    1978-11-01

    The biological degradation of phenolic scrub liquors similar to those that arise in coal conversion processes was studied for symbiotic bacterial populations contained in a continuously stirred tank bioreactor, a three-phase packed-bed bioreactor, and a three-phase, fluidized-bed bioreactor. The conversions of phenol compounds were comparable in the three-phase, packed-bed bioreactor and the continuously stirred tank bioreactor; however, the packed-bed bioreactor degradation rates were as much as twice those in the continuously stirred tank bioreactor, and packed-bed bioreactor retention times were as low as one- tenth those of the continuously stirred tank bioreactors (minimum time was 12 hours).

  15. Bed and bed-site reuse by western lowland gorillas (Gorilla g. gorilla) in Moukalaba-Doudou National Park, Gabon.

    Science.gov (United States)

    Iwata, Yuji; Ando, Chieko

    2007-01-01

    In this paper we describe bed (nest) and bed-site reuse by western lowland gorillas (Gorilla g. gorilla) in Moukalaba-Doudou National Park, south-eastern Gabon. During an eight-month study 44 bed sites and 506 beds were found. Among these, 38.6% of bed sites and 4.1% of beds were reused. We analyzed the monthly frequency of bed-site reuse in relation to rainfall, fruit abundance, and fruit consumption by the gorillas. The different frequency of bed-site reuse in the rainy and dry seasons was not significant. More bed-site reuse was observed during the fruiting season than during the non-fruiting season. Results from fecal analysis suggested that gorillas ate more fruit in the fruiting season than in the non-fruiting season. The frugivorous diet of western gorillas may possibly cause gorillas to stay in some areas and, consequently, reuse their bed sites. Reuse of bed sites by gorillas suggests their frequent return to an area where preferred fruit is readily available. A higher percentage of arboreal beds may also affect bed-site reuse, because of the shortage of bed material.

  16. An Intelligent FPGA Based Anti-Sweating System for Bed Sore Prevention in a Clinical Environment

    Directory of Open Access Journals (Sweden)

    K. S. Jaichandar

    2011-01-01

    Full Text Available Bed sores, a common problem among immobile patients occur as a result of continuous sweating due to increase in skin to bed surface temperature in patients lying on same posture for prolonged period. If left untreated, the skin can break open and become infected. Currently adopted methods for bed sores prevention include: use of two hourly flip chat for repositioning patient or use of air fluidized beds. However, the setbacks of these preventive measures include either use of costly equipment or wastage of human resources. This paper introduces an intelligent low cost FPGA based anti-sweating system for bed sores prevention in a clinical environment. The developed system consists of bed surface implanted temperature sensors interfaced with an FPGA chip for sensing the temperature change in patient’s skin to bed surface. Based on the temperature change, the FPGA chip select the - mode (heater/cooler and speed of the fan module. Furthermore, an alarm module was implemented to alert the nurse to reposition the patient only if patient’s skin to bed surface temperature exceeds a predefined threshold thereby saving human resources. By integrating the whole system into a single FPGA chip, we were able to build a low cost compact system without sacrificing processing power and flexibility.

  17. Phylogeny of the true water bugs (Nepomorpha: Hemiptera–Heteroptera) based on 16S and 28S rDNA and morphology

    DEFF Research Database (Denmark)

    Hebsgaard, Martin Bay; Andersen, Nils M.; Damgaard, Jakob

    2004-01-01

    Morphological characters and molecular sequence data were for the first time analysed separately and combined for the true water bugs (Hemiptera-Heteroptera, infraorder Nepomorpha). Data from forty species representing all families were included, together with two outgroup species representing...

  18. Current scientific literature on tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) ecology in Mississippi, and critical information needs

    Science.gov (United States)

    Understanding the basic ecological patterns of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is required for implementing a successful integrated pest management program. As the primary pest of cotton in Mississippi and across the mid-south, L. lineolaris is a highly polyphagous m...

  19. Hazardous Air Pollutants

    Science.gov (United States)

    ... Search Main menu Environmental Topics Air Bed Bugs Chemicals and Toxics Environmental Information by Location Greener Living Health Land, ... regulate toxic air pollutants, also known as air toxics, from categories of industrial facilities in two phases . About Hazardous Air Pollutants ...

  20. The effect of vibration on bed voidage behaviors in fluidized beds with large particles

    Directory of Open Access Journals (Sweden)

    H. Jin

    2007-09-01

    Full Text Available The effects of vibration parameters, operating conditions and material properties on bed voidage were investigated using an optical fiber probe approach in a vibrating fluidized bed with a diameter of 148 mm. Variables studied included frequency (0-282 s-1, amplitude (0 mm-1 mm, bed height (0.1 m-0.4 m as well as four kinds of particles (belonging to Geldart's B and D groups. The axial and radial voidage distribution with vibration is compared with that without vibration, which shows vibration can aid in the fluidization behaviors of particles. For a larger vibration amplitude, the vibration seriously affects bed voidage. The vibration energy can damp out for particle layers with increasing the bed height. According to analysis of experimental data, an empirical correlation for predicting bed voidage, giving good agreement with the experimental data and a deviation within ±15%, was proposed.

  1. Direct contact condensation in packed beds

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yi; Klausner, James F.; Mei, Renwei; Knight, Jessica [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL 32611 (United States)

    2006-12-15

    A diffusion driven desalination process was recently described where a very effective direct contact condenser with a packed bed is used to condense water vapor out of an air/vapor mixture. A laboratory scale direct contact condenser has been fabricated as a twin tower structure with two stages, co-current and countercurrent. Experiments have been operated in each stage with respective saturated air inlet temperatures of 36, 40 and 43{sup o}C. The temperature and humidity data have been collected at the inlet and exit of the packed bed for different water to air mass flow ratios that vary between 0 and 2.5. A one-dimensional model based on conservation principles has been developed, which predicts the variation of temperature, humidity, and condensation rate through the condenser stages. Agreement between the model and experiments is very good. It is observed that the countercurrent flow stage condensation effectiveness is significantly higher than that for the co-current stage. The condensation heat and mass transfer rates were found to decrease when water blockages occur within the packed bed. Using high-speed digital cinematography, it was observed that this problem can occur at any operating condition, and is dependent on the packing surface wetting characteristics. This observation is used to explain the requirement for two different empirical constants, depending on packing diameter, suggested by Onda for the air side mass transfer coefficient correlation. (author)

  2. Parent-child bed-sharing: The good, the bad, and the burden of evidence.

    Science.gov (United States)

    Mileva-Seitz, Viara R; Bakermans-Kranenburg, Marian J; Battaini, Chiara; Luijk, Maartje P C M

    2017-04-01

    The practice of parent and child sharing a sleeping surface, or 'bed-sharing', is one of the most controversial topics in parenting research. The lay literature has popularized and polarized this debate, offering on one hand claims of dangers, and on the other, of benefits - both physical and psychological - associated with bed-sharing. To address the scientific evidence behind such claims, we systematically reviewed 659 published papers (peer-reviewed, editorial pieces, and commentaries) on the topic of parent-child bed-sharing. Our review offers a narrative walkthrough of the many subdomains of bed-sharing research, including its many correlates (e.g., socioeconomic and cultural factors) and purported risks or outcomes (e.g., sudden infant death syndrome, sleep problems). We found general design limitations and a lack of convincing evidence in the literature, which preclude making strong generalizations. A heat-map based on 98 eligible studies aids the reader to visualize world-wide prevalence in bed-sharing and highlights the need for further research in societies where bed-sharing is the norm. We urge for multiple subfields - anthropology, psychology/psychiatry, and pediatrics - to come together with the aim of understanding infant sleep and how nightly proximity to the parents influences children's social, emotional, and physical development. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Are environmental factors responsible for geographic variation in the sex ratio of the Greenlandic seed-bug Nysius groenlandicus?

    DEFF Research Database (Denmark)

    Bøcher, Jens Jensenius; Nachman, Gøsta Støger

    2010-01-01

    Until recently nothing indicated an unequal sex ratio in the widespread Greenland seed-bug Nysius groenlandicus (Zetterstedt) (Heteroptera: Lygaeidae). However, recently populations more or less devoid of males were discovered in high arctic Northeast Greenland. This initiated an inspection of th...

  4. Loading and Unloading Weaned Pigs: Effects of Bedding Types, Ramp Angle, and Bedding Moisture

    Directory of Open Access Journals (Sweden)

    Arlene Garcia

    2014-12-01

    Full Text Available The use of non-slip surfaces during loading and unloading of weaned pigs plays an important role in animal welfare and economics of the pork industry. Currently, the guidelines available only suggest the use of ramps below 20° to load and unload pigs. Three ramp angles (0°, 10° or 20°, five bedding materials (nothing, sand, feed, wood shavings or wheat straw hay, two moistures (dry or wet bedding; >50% moisture over two seasons (>23.9 °C summer, <23.9 °C winter were assessed for slips/falls/vocalizations (n = 6,000 pig observations. “Score” was calculated by the sum of slips, falls, and vocalizations. With the exception of using feed as a bedding, all beddings provided some protection against elevated slips, falls, and vocalizations (P < 0.01. Providing bedding reduced (P < 0.05 scores regardless of whether the bedding was dry or wet. Scores increased as the slope increased (P < 0.01. Provision of bedding, other than feed, at slopes greater than zero, decreased slips, falls and vocalizations. The total time it took to load and unload pigs was

  5. Experimental studies on the coolability of packed beds. Flooding of hot dry packed beds

    International Nuclear Information System (INIS)

    Leininger, S.; Kulenovic, R.; Laurien, E.

    2013-01-01

    In case of a severe accident in a nuclear power plant meltdown of the reactor core can occur and form a packed bed in the lower plenum of the reactor pressure vessel (RPV) after solidification due to contact with water. The removal of after-heat and the long-term coolability is of essential interest. The efficient injection of cooling water into the packed bed has to be assured without endangering the structural integrity of the reactor pressure vessel. The experiments performed aimed to study the dry-out and the quenching (flooding) of hot dry packed beds. Two different inflow variants, bottom- and top-flooding including the variation of the starting temperature of the packed bed and the injection rate were studied. In case of bottom flooding the quenching time increases with increasing packed bed temperature and decreasing injection rate. In case of top flooding the flow pattern is more complex, in a first phase the water flows preferentially toward the RPV wall, the flow paths conduct the water downwards. The flow resistance of the packed bed increases with increasing bed temperatures. The quenching temperatures increase significantly above average.

  6. Operating experience and development of fluidized-bed denitrators for UNH at Tokai Reprocessing Plant

    International Nuclear Information System (INIS)

    Sasaki, Minoru; Nakamichi, Hideya; Takeda, Seiichiro; Kubota, Kanya; Katoh, Shuji

    1983-01-01

    The fluidized bed denitrator for uranyl nitrate hexahydrate (UNH) at Tokai reprocessing plant has been operated since 1976. About 170 tons of spent fuel have been reprocessed, and the denitrator has encountered numerous operational problems during the period. This report deals with these technical problems and the associated countermeasures taken, including the dismantling and reconstruction of equipment and the improvement of operating method. The major problems encountered were as follows: (1) the crystallization of UNH on the UNH feeding line, (2) spray nozzle clogging and candle filter clogging, (3) particle growth, (4) plugging of the drawing-out line by nozzle caking, and (5) slugging in fluidized-bed denitration. The total quantity and quality of UO 3 products obtained so far at the plant are also briefly described together with some future R and D programs such as the improvement of UO 3 reactivity and the automation of denitrators. (Aoki, K.)

  7. Insect bite reactions

    Directory of Open Access Journals (Sweden)

    Sanjay Singh

    2013-01-01

    Full Text Available Insects are a class of living creatures within the arthropods. Insect bite reactions are commonly seen in clinical practice. The present review touches upon the medically important insects and their places in the classification, the sparse literature on the epidemiology of insect bites in India, and different variables influencing the susceptibility of an individual to insect bites. Clinical features of mosquito bites, hypersensitivity to mosquito bites Epstein-Barr virus NK (HMB-EBV-NK disease, eruptive pseudoangiomatosis, Skeeter syndrome, papular pruritic eruption of HIV/AIDS, and clinical features produced by bed bugs, Mexican chicken bugs, assassin bugs, kissing bugs, fleas, black flies, Blandford flies, louse flies, tsetse flies, midges, and thrips are discussed. Brief account is presented of the immunogenic components of mosquito and bed bug saliva. Papular urticaria is discussed including its epidemiology, the 5 stages of skin reaction, the SCRATCH principle as an aid in diagnosis, and the recent evidence supporting participation of types I, III, and IV hypersensitivity reactions in its causation is summarized. Recent developments in the treatment of pediculosis capitis including spinosad 0.9% suspension, benzyl alcohol 5% lotion, dimethicone 4% lotion, isopropyl myristate 50% rinse, and other suffocants are discussed within the context of evidence derived from randomized controlled trials and key findings of a recent systematic review. We also touch upon a non-chemical treatment of head lice and the ineffectiveness of egg-loosening products. Knockdown resistance (kdr as the genetic mechanism making the lice nerves insensitive to permethrin is discussed along with the surprising contrary clinical evidence from Europe about efficacy of permethrin in children with head lice carrying kdr-like gene. The review also presents a brief account of insects as vectors of diseases and ends with discussion of prevention of insect bites and some

  8. Altered gene regulation and potential association with metabolic resistance development to imidacloprid in the tarnished plant bug, Lygus lineolaris

    Science.gov (United States)

    Chemical spray on cotton is almost an exclusive method for control of tarnished plant bug (TPB, Lygus lineolaris). Frequent use of imidacloprid is a concern for neonicotinoid resistance in this key pest. Information of how and why TPB become less susceptible to imidacloprid is essential for effectiv...

  9. Integrative review of indigenous arthropod natural enemies of the invasive brown marmorated stink bug in North America and Europe

    Science.gov (United States)

    Since the establishment of the brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae) in North America and Europe, there has been a large, multi-group effort to characterize the composition and impact of the indigenous community of arthropod natural enemies attacking this invas...

  10. The impact of the invasive brown marmorated stink bug in North America and Europe: history, biology, ecology, and management

    Science.gov (United States)

    Brown marmorated stink bug (BMSB), Halyomorpha halys (Stål), is an invasive Pentatomidae introduced to the USA, Canada, and multiple European countries. In 2010, BMSB populations in the mid-Atlantic region USA reached outbreak levels, and subsequent feeding resulted in severe damage to tree fruit a...

  11. Strategies for fitting nonlinear ecological models in R, AD Model Builder, and BUGS

    DEFF Research Database (Denmark)

    Bolker, B.M.; Gardner, B.; Maunder, M.

    2013-01-01

    Ecologists often use nonlinear fitting techniques to estimate the parameters of complex ecological models, with attendant frustration. This paper compares three open-source model fitting tools and discusses general strategies for defining and fitting models. R is convenient and (relatively) easy...... to learn, AD Model Builder is fast and robust but comes with a steep learning curve, while BUGS provides the greatest flexibility at the price of speed. Our model-fitting suggestions range from general cultural advice (where possible, use the tools and models that are most common in your subfield...

  12. Multicell fluidized bed boiler design construction and test program. Quarterly progress status report, January--March 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-07-01

    The objective of this program is to design, construct, and test a multicell fluidized-bed boiler as a pollution-free method of burning high-sulfur or highly corrosive coals without excessive maintenance problems. The fluidized-bed boiler will provide approximately 300,000 pounds of steam per hour. Steam pressure and temperature conditions were selected to meet requirements of the site at which the boiler was installed.

  13. Infestation of Broad Bean (Vicia faba) by the Green Stink Bug (Nezara viridula) Decreases Shoot Abscisic Acid Contents under Well-Watered and Drought Conditions.

    Science.gov (United States)

    Ederli, Luisa; Brunetti, Cecilia; Centritto, Mauro; Colazza, Stefano; Frati, Francesca; Loreto, Francesco; Marino, Giovanni; Salerno, Gianandrea; Pasqualini, Stefania

    2017-01-01

    The response of broad bean ( Vicia faba ) plants to water stress alone and in combination with green stink bug ( Nezara viridula ) infestation was investigated through measurement of: (1) leaf gas exchange; (2) plant hormone titres of abscisic acid (ABA) and its metabolites, and of salicylic acid (SA); and (3) hydrogen peroxide (H 2 O 2 ) content. Furthermore, we evaluated the effects of experimentally water-stressed broad-bean plants on N. viridula performance in terms of adult host-plant preference, and nymph growth and survival. Water stress significantly reduced both photosynthesis ( A ) and stomatal conductance ( g s ), while infestation by the green stink bug had no effects on photosynthesis but significantly altered partitioning of ABA between roots and shoots. Leaf ABA was decreased and root ABA increased as a result of herbivore attack, under both well-watered and water-deprived conditions. Water stress significantly impacted on SA content in leaves, but not on H 2 O 2 . However, infestation of N. viridula greatly increased both SA and H 2 O 2 contents in leaves and roots, which suggests that endogenous SA and H 2 O 2 have roles in plant responses to herbivore infestation. No significant differences were seen for green stink bug choice between well-watered and water-stressed plants. However, for green stink bug nymphs, plant water stress promoted significantly lower weight increases and significantly higher mortality, which indicates that highly water-stressed host plants are less suitable for N. viridula infestation. In conclusion two important findings emerged: (i) association of water stress with herbivore infestation largely changes plant response in terms of phytohormone contents; but (ii) water stress does not affect the preference of the infesting insects, although their performance was impaired.

  14. The effect of bed non-uniformities and porosity of particles on dryout in boiling particle beds

    International Nuclear Information System (INIS)

    Macbeth, R.V.; Mogford, D.J.; Willshire, S.J.

    1988-03-01

    This report relates to an on-going experimental programme concerned with the coolability of beds of reactor core debris or rubble immersed in a liquid coolant, as might occur in an accident situation. The objectives are to develop experimental techniques, improve the understanding of bed cooling mechanisms, determine dry-out limitations of various bed configurations and particle shapes and sizes and devise ways of improving bed coolability. The report concentrates on a recently discovered effect on bed coolability of particle porosity, such as exists in fragmented UO 2 fuel pellets. It is shown that porosity can lower bed dry-out powers by a factor of 4 or 5. A mechanism which explains the effect is presented. The report also gives results of bed non-uniformities obtained by mixing glass particles with the dielectrically heated 'ferrite' particles used in the experiments. (author)

  15. Thermo-catalytic pyrolysis of waste polyethylene bottles in a packed bed reactor with different bed materials and catalysts

    International Nuclear Information System (INIS)

    Obeid, Farah; Zeaiter, Joseph; Al-Muhtaseb, Ala’a H.; Bouhadir, Kamal

    2014-01-01

    Highlights: • Thermo-catalytic pyrolysis of waste polyethylene bottles was investigated. • The highest yield of liquid (82%) was obtained over a cement powder bed. • Acidic catalysts narrowed the carbon chain length of the paraffins to C 10 –C 28 . • Combination of cement bed with HBeta catalyst gave the highest yield of liquid. • Significant yield of aromatics was obtained mainly naphthalene and D-limonene. - Abstract: Plastic waste is an increasing economic and environmental problem as such there is a great need to process this waste and reduce its environmental impact. In this work, the pyrolysis of high density polyethylene (HDPE) waste products was investigated using both thermal and catalytic cracking techniques. The experimental work was carried out using packed bed reactor operating under an inert atmosphere at 450 °C. Different reactor bed materials, including sand, cement and white clay were used to enhance the thermal cracking of HDPE. In addition, the catalytic effect of sodium hydroxide, HUSY and HBeta zeolite catalysts on the degradation of HDPE waste was also investigated. The reactor beds were found to significantly alter the yield as well as the product composition. Products such as paraffins (⩽C 44 ), olefins (⩽C 22 ), aromatics (⩽C 14 ) and alcohols (C 16 and C 17 ) were obtained at varying rates. The highest yield of liquid (82%) was obtained over a cement powder bed with a paraffin yield of 58%. The yield of paraffins and olefins followed separate paths, for paraffins it was found to increase in the order or Cement > White clay > Silica Sand, whereas for the olefins it was in the reverse order Silica Sand > White clay > Cement. The results obtained in this work exhibited a higher P/O ratio than expected, where the amount of generated paraffins was greater than 60% in most cases. Less olefin was generated as a consequence. This indicates that the product generated is more suited to be used as a fuel rather than as a chemical

  16. Psychological effects of acute physical inactivty during microgravitiy simulated by bed rest

    Directory of Open Access Journals (Sweden)

    Petra Dolenc

    2009-05-01

    Full Text Available Long-duration weightlessness simulated by bed rest represents an important model to study the consequences of physical inactivity and sedentarism on the human body. This study evaluated changes of mood status, psychological well-being, coping strategies and physical self in ten healthy young male subjects during a 35-day horizontal bed rest. Participants were asked to complete psychometrical inventories before and after the bed rest experiment. The preceived satisfaction with life and the physical self-concept did not change during bed rest period and mood states were relatively stable during the experiment according to the Emotional States Questionnaire. The neurotic level was enhanced during the bed rest period according to the Slovenian version of the General Health Questionnaire. However, even after the period of physical immobilization, the expression of these symptoms remains relatively low and does not represent a risk to the mental health of the subjects. The results from Coping Resources Inventory indicated a tendency toward an increase of emotion focused coping and a decrease of problem focused coping strategies. The importance of this research was to provide evidence that the provision of favourable habitability countermeasures can prevent deterioration in the psychological state under conditions of physical immobilisation. Our findings have applied value in the field of health prevention and rehabilitaion.

  17. Comparative genomics evidence that only protein toxins are tagging bad bugs

    Directory of Open Access Journals (Sweden)

    Kalliopi eGeorgiades

    2011-10-01

    Full Text Available The term toxin was introduced by Roux and Yersin and describes macromolecular substances that, when produced during infection or when introduced parenterally or orally, cause an impairment of physiological functions that lead to disease or to the death of the infected organism. Long after the discovery of toxins, early genetic studies on bacterial virulence demonstrated that removing a certain number of genes from pathogenic bacteria decreases their capacity to infect hosts. Each of the removed factors was therefore referred to as a virulence factor, and it was speculated that non-pathogenic bacteria lack such supplementary factors. However, many recent comparative studies demonstrate that the specialization of bacteria to eukaryotic hosts is associated with massive gene loss. We recently demonstrated that the only features that seem to characterize 12 epidemic bacteria are toxin-antitoxin (TA modules, which are addiction molecules in host bacteria. In this study, we investigated if protein toxins are indeed the only molecules specific to pathogenic bacteria by comparing 14 epidemic bacterial killers (bad bugs with their 14 closest non-epidemic relatives (controls. We found protein toxins in significantly more elevated numbers in all of the bad bugs. For the first time, statistical principal components analysis, including genome size, GC%, TA modules, restriction enzymes and toxins, revealed that toxins are the only proteins other than TA modules that are correlated with the pathogenic character of bacteria. Moreover, intracellular toxins appear to be more correlated with the pathogenic character of bacteria than secreted toxins. In conclusion, we hypothesize that the only truly identifiable phenomena, witnessing the convergent evolution of the most pathogenic bacteria for humans are the loss of metabolic activities, i.e., the outcome of the loss of regulatory and transcription factors and the presence of protein toxins, alone or coupled as TA

  18. Experimental measurement of variation of heat transfer coefficient and temperature gradients in 16'' deep fluidised beds

    International Nuclear Information System (INIS)

    Blacker, P.T.; McLain, D.R.

    1962-04-01

    The object of the experiments was to choose suitable particulate materials for a fluidised bed cooler, to test a deep fluidised bed for uniformity of heat transfer coefficient, and to explore the temperature distribution in a centrally heated annular fluidised bed. This memorandum records the techniques used and some of the practical aspects involved, together with the performance results obtained, for the assistance of other experimenters who may wish to use fluidised beds as a laboratory technique. Mathematical correlation of the results has not been attempted since some of the properties of the bed material were not known and to determine them was beyond the scope of the work programme. Rather, we have compared our results with those of other experimenters. Graphite tubes, for use in steady state thermal stress experiments, are to be heated by a graphite radiant heater situated in the bore and cooled on the outer surface. The tubes are 2 cm. bore, 8 cm. outside diameter and 48 cm. long. The outside temperature of the tubes is to be between 500 deg. C. and 1500 deg. C. It is estimated that the heat transfer rate required for fracture at the outer surface is 30 watts/cm 2 . This could readily be achieved by cooling with liquid metals, water or high velocity gas. However, serious problems of either materials compatibility or mechanical complexity make these undesirable. A water-cooled fluidised bed of compatible solids fluidised with nitrogen gas can overcome most of these problems and give heat transfer coefficients close to that required, vis. about 0.1 w/cm C . A coolant bed about 20'' long would be required and an annulus of about 2'' radial width round the specimen was considered to be practicable

  19. Experimental measurement of variation of heat transfer coefficient and temperature gradients in 16'' deep fluidised beds

    Energy Technology Data Exchange (ETDEWEB)

    Blacker, P T; McLain, D R [Reactor Development Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

    1962-04-15

    The object of the experiments was to choose suitable particulate materials for a fluidised bed cooler, to test a deep fluidised bed for uniformity of heat transfer coefficient, and to explore the temperature distribution in a centrally heated annular fluidised bed. This memorandum records the techniques used and some of the practical aspects involved, together with the performance results obtained, for the assistance of other experimenters who may wish to use fluidised beds as a laboratory technique. Mathematical correlation of the results has not been attempted since some of the properties of the bed material were not known and to determine them was beyond the scope of the work programme. Rather, we have compared our results with those of other experimenters. Graphite tubes, for use in steady state thermal stress experiments, are to be heated by a graphite radiant heater situated in the bore and cooled on the outer surface. The tubes are 2 cm. bore, 8 cm. outside diameter and 48 cm. long. The outside temperature of the tubes is to be between 500 deg. C. and 1500 deg. C. It is estimated that the heat transfer rate required for fracture at the outer surface is 30 watts/cm{sup 2}. This could readily be achieved by cooling with liquid metals, water or high velocity gas. However, serious problems of either materials compatibility or mechanical complexity make these undesirable. A water-cooled fluidised bed of compatible solids fluidised with nitrogen gas can overcome most of these problems and give heat transfer coefficients close to that required, vis. about 0.1 w/cm C . A coolant bed about 20'' long would be required and an annulus of about 2'' radial width round the specimen was considered to be practicable.

  20. Controlling Bed Bugs Using Integrated Pest Management (IPM)

    Science.gov (United States)

    Several non-chemical methods can help control an infestation, such as heat treatment or freezing, or mattress and box spring encasements. When using a pesticide, follow label directions carefully and check for EPA registration.

  1. Geological Changes of the Americas and their Influence on the Diversification of the Neotropical Kissing Bugs (Hemiptera: Reduviidae: Triatominae).

    Science.gov (United States)

    Justi, Silvia A; Galvão, Cleber; Schrago, Carlos G

    2016-04-01

    The family Reduviidae (Hemiptera: Heteroptera), or assassin bugs, is among the most diverse families of the true bugs, with more than 6,000 species. The subfamily Triatominae (kissing bugs) is noteworthy not simply because it is the only subfamily of the Reduviidae whose members feed on vertebrate blood but particularly because all 147 known members of the subfamily are potential Chagas disease vectors. Due to the epidemiological relevance of these species and the lack of an efficient treatment and vaccine for Chagas disease, it is more common to find evolutionary studies focusing on the most relevant vectors than it is to find studies aiming to understand the evolution of the group as a whole. We present the first comprehensive phylogenetic study aiming to understand the events that led to the diversification of the Triatominae. We gathered the most diverse samples of Reduviidae and Triatominae (a total of 229 Reduviidae samples, including 70 Triatominae species) and reconstructed a robust dated phylogeny with several fossil (Reduviidae and Triatominae) calibrations. Based on this information, the possible role of geological events in several of the major cladogenetic events within Triatominae was tested for the first time. We were able to not only correlate the geological changes in the Neotropics with Triatominae evolution but also add to an old discussion: Triatominae monophyly vs. paraphyly. We found that most of the diversification events observed within the Rhodniini and Triatomini tribes are closely linked to the climatic and geological changes caused by the Andean uplift in South America and that variations in sea levels in North America also played a role in the diversification of the species of Triatoma in that region.

  2. Uso de WinBUGS en los métodos bayesianos. Una aplicación en auditoría

    Directory of Open Access Journals (Sweden)

    Vázquez Polo, Francisco José

    2001-01-01

    Full Text Available Lo que se presenta es un breve recorrido por el programa WinBUGS, desarrollado para problemas de inferencia estadística bayesiana haciendo uso de métodos Markov Chain Monte Carlo, MCMC. Una dificultad recurrente en la inferencia bayesiana ha sido la enorme complejidad computacional que presenta en muchos casos el cálculo de cantidades a posteriori de interés. En los últimos años se están utilizando los métodos MCMC, que mediante la simulación Monte Carlo de cadenas de Markov, permiten salvar estas dificultades. El programa WinBUGS, de libre acceso en la red y diseñado por los británicos Spiegelhalter, Thomas y Best, implementa estas técnicas, y posibilita su uso a un amplio número de usuarios de la estadística bayesiana aplicada. En concreto, en este trabajo se presenta un ejemplo de su uso en un modelo de Auditoría Contable, para el cálculo del error total en una contabilidad.

  3. Sequential testing scheme for the assessment of the side-effects of plant protection products on the predatory bug Orius laevigatus

    NARCIS (Netherlands)

    Veire, Van de M.; Sterk, G.; Staaij, van der M.; Ramakers, P.M.J.; Tirry, L.

    2002-01-01

    This paper describes a number of test methods, to beused in a sequential scheme, for testing the side-effects ofplant protection products on anthocorid bugs. Orius laevigatuswas used as test species. A `worst case' laboratory method wasdeveloped for evaluating the effect on mortality of the

  4. Seaweed beds support more juvenile reef fish than seagrass beds in a south-western Atlantic tropical seascape

    Science.gov (United States)

    Eggertsen, L.; Ferreira, C. E. L.; Fontoura, L.; Kautsky, N.; Gullström, M.; Berkström, C.

    2017-09-01

    Seascape connectivity is regarded essential for healthy reef fish communities in tropical shallow systems. A number of reef fish species use separate adult and nursery habitats, and hence contribute to nutrient and energy transfer between habitats. Seagrass beds and mangroves often constitute important nursery habitats, with high structural complexity and protection from predation. Here, we investigated if reef fish assemblages in the tropical south-western Atlantic demonstrate ontogenetic habitat connectivity and identify possible nurseries on three reef systems along the eastern Brazilian coast. Fish were surveyed in fore reef, back reef, Halodule wrightii seagrass beds and seaweed beds. Seagrass beds contained lower abundances and species richness of fish than expected, while Sargassum-dominated seaweed beds contained significantly more juveniles than all other habitats (average juvenile fish densities: 32.6 per 40 m2 in Sargassum beds, 11.2 per 40 m2 in back reef, 10.1 per 40 m2 in fore reef, and 5.04 per 40 m2 in seagrass beds), including several species that are found in the reef habitats as adults. Species that in other regions worldwide (e.g. the Caribbean) utilise seagrass beds as nursery habitats were here instead observed in Sargassum beds or back reef habitats. Coral cover was not correlated to adult fish distribution patterns; instead, type of turf was an important variable. Connectivity, and thus pathways of nutrient transfer, seems to function differently in east Brazil compared to many tropical regions. Sargassum-dominated beds might be more important as nurseries for a larger number of fish species than seagrass beds. Due to the low abundance of structurally complex seagrass beds we suggest that seaweed beds might influence adult reef fish abundances, being essential for several keystone species of reef fish in the tropical south-western Atlantic.

  5. Investigation of heat transfer in bed and freeboard of fluidized bed combustors

    International Nuclear Information System (INIS)

    Mitor, V.V.; Matsnev, V.V.; Sorokin, A.P.

    1986-01-01

    Experimental results for heat transfer between immersed bundles of bare tubes and fluidized beds are reported. The experimental results are obtained on industrial boilers with a bed area from 2,5 to 4 m/sup 2/ under conditions of long term operation. The bed temperature range has been 1073 0 K-1233 0 K, gas velocity between 1,8-4,5 m/s, mean particle size from 1,5 mm to 6,0 mm, freeboard furnace height of 2,3 and 5 m. The obtained data are compared with experimental results from literature

  6. Hox gene function and interaction in the milkweed bug Oncopeltus fasciatus (Hemiptera).

    Science.gov (United States)

    Angelini, David R; Liu, Paul Z; Hughes, Cynthia L; Kaufman, Thomas C

    2005-11-15

    Studies in genetic model organisms such as Drosophila have demonstrated that the homeotic complex (Hox) genes impart segmental identity during embryogenesis. Comparative studies in a wide range of other insect taxa have shown that the Hox genes are expressed in largely conserved domains along the anterior-posterior body axis, but whether they are performing the same functions in different insects is an open question. Most of the Hox genes have been studied functionally in only a few holometabolous insects that undergo metamorphosis. Thus, it is unclear how the Hox genes are functioning in the majority of direct-developing insects and other arthropods. To address this question, we used a combination of RNAi and in situ hybridization to reveal the expression, functions, and regulatory interactions of the Hox genes in the milkweed bug Oncopeltus fasciatus. Our results reveal many similarities and some interesting differences compared to Drosophila. We find that the gene Antennapedia is required for the identity of all three thoracic segments, while Ultrabithorax, abdominal-A and Abdominal-B cooperate to pattern the abdomen. The three abdominal genes exhibit posterior prevalence like in Drosophila, but apparently via some post-transcriptional mechanism. The functions of the head genes proboscipedia, Deformed, and Sex combs reduced were shown previously, and here we find that the complex temporal expression of pb in the labium is like that of other insects, but its regulatory relationship with Scr is unique. Overall, our data reveal that the evolution of insect Hox genes has included many small changes within general conservation of expression and function, and that the milkweed bug provides a useful model for understanding the roles of Hox genes in a direct-developing insect.

  7. The ecotopes and evolution of triatomine bugs (triatominae and their associated trypanosomes

    Directory of Open Access Journals (Sweden)

    Gaunt Michael

    2000-01-01

    Full Text Available Triatomine bug species such as Microtriatoma trinidadensis, Eratyrus mucronatus, Belminus herreri, Panstrongylus lignarius, and Triatoma tibiamaculata are exquisitely adapted to specialist niches. This suggests a long evolutionary history, as well as the recent dramatic spread a few eclectic, domiciliated triatomine species. Virtually all species of the genus Rhodnius are primarily associated with palms. The genus Panstrongylus is predominantly associated with burrows and tree cavities and the genus Triatoma with terrestrial rocky habitats or rodent burrows. Two major sub-divisions have been defined within the species Trypanosoma cruzi, as T. cruzi 1 (Z1 and T. cruzi 2 (Z2. The affinities of a third group (Z3 are uncertain. Host and habitat associations lead us to propose that T. cruzi 1 (Z1 has evolved in an arboreal, palm tree habitat with the triatomine tribe Rhodniini, in association with the opossum Didelphis. Similarly we propose that T. cruzi (Z2 and Z3 evolved in a terrestrial habitat in burrows and in rocky locations with the triatomine tribe Triatomini, in association with edentates, and/or possibly ground dwelling marsupials. Both sub-divisions of T. cruzi may have been contemporary in South America up to 65 million years ago. Alternatively, T. cruzi 2 (Z2 may have evolved more recently from T. cruzi 1 (Z1 by host transfers into rodents, edentates, and primates. We have constructed a molecular phylogeny of haematophagous vectors, including triatomine bugs, which suggests that faecal transmission of trypanosomes may be the ancestral route. A molecular clock phylogeny suggests that Rhodnius and Triatoma diverged before the arrival, about 40 million years ago, of bats and rodents into South America.

  8. Fluidized bed combustion with the use of Greek solid fuels

    Directory of Open Access Journals (Sweden)

    Kakaras Emmanuel

    2003-01-01

    Full Text Available The paper is an overview of the results obtained up to date from the combustion and co-combustion activities with Greek brown coal in different installations, both in semi-industrial and laboratory scale. Combustion tests with Greek lignite were realized in three different Circulating Fluidized Bed Combustion (CFBC facilities. Low rank lignite was burned in a pilot scale facility of approx. 100kW thermal capacity, located in Athens (NTUA and a semi-industrial scale of 1.2 MW thermal capacity, located at RWE's power station Niederaussem in Germany. Co-combustion tests with Greek xylitic lignite and waste wood were carried out in the 1 MWth CFBC installation of AE&E, in Austria. Lab-scale co-combustion tests of Greek pre-dried lignite with biomass were accomplished in a bubbling fluidized bed in order to investigate ash melting problems. The obtained results of all aforementioned activities showed that fluidized bed is the appropriate combustion technology to efficiently exploit the low quality Greek brown coal either alone or in conjunction with biomass species.

  9. Improved lignin pyrolysis for phenolics production in a bubbling bed reactor--Effect of bed materials.

    Science.gov (United States)

    Li, Dongbing; Briens, Cedric; Berruti, Franco

    2015-01-01

    Lignin pyrolysis was studied in a bubbling fluidized bed reactor equipped with a fractional condensation train, using nitrogen as the fluidization gas. The effect of different bed materials (silica sand, lignin char, activated lignin char, birch bark char, and foamed glass beads) on bio-oil yield and quality was investigated for a pyrolysis temperature of 550 °C. Results how that a bed of activated lignin char is preferable to the commonly used silica sand: pyrolysis of Kraft lignin with a bed of activated lignin char not only provides a pure char product, but also a higher dry bio-oil yield (with a relative increase of 43%), lower pyrolytic water production, and better bio-oil quality. The bio-oil obtained from Kraft lignin pyrolysis with a bed of activated lignin char has a lower average molecular weight, less tar, more phenolics, and less acidity than when sand is used as bed material. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Peculiarities of the hydrological regime of the fishery water reservoirs at the basin of the Southern Bug of Vinnytsia region

    OpenAIRE

    V. Baban; I. Gamaliy.

    2014-01-01

    This paper deals with analysis of hydrological regime of the fishery water reservoirs at the basin of the Southern Bug of Vinnytsia region. Systematization of the investigated water bodies was performed by the authors on the basis of previously developed classification and typing of water reservoirs.

  11. Uranium bed oxidation vacuum process system

    International Nuclear Information System (INIS)

    McLeland, H.L.

    1977-01-01

    Deuterium and tritium gases are occluded in uranium powder for release into neutron generator tubes. The uranium powder is contained in stainless steel bottles, termed ''beds.'' If these beds become damaged, the gases must be removed and the uranium oxidized in order not to be flammable before shipment to ERDA disposal grounds. This paper describes the system and methods designed for the controlled degassing and oxidation process. The system utilizes sputter-ion, cryo-sorption and bellows pumps for removing the gases from the heated source bed. Removing the tritium gas is complicated by the shielding effect of helium-3, a byproduct of tritium decay. This effect is minimized by incremental pressure changes, or ''batch'' processing. To prevent runaway exothermic reaction, oxidation of the uranium bed is also done incrementally, or by ''batch'' processing, rather than by continuous flow. The paper discusses in detail the helium-3 shielding effect, leak checks that must be made during processing, bed oxidation, degree of gas depletion, purity of gases sorbed from beds, radioactivity of beds, bed disposal and system renovation

  12. Practice Hospital Bed Safety

    Science.gov (United States)

    ... Home For Consumers Consumer Updates Practice Hospital Bed Safety Share Tweet Linkedin Pin it More sharing options ... It depends on the complexity of the bed." Safety Tips CDRH offers the following safety tips for ...

  13. Bioenergy originating from biomass combustion in a fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Crujeira, T.; Gulyurtlu, I.; Lopes, H.; Abelha, P.; Cabrita, I. [INETI/DEECA, Lisboa (Portugal)

    2008-07-01

    Bioenergy could significantly contribute to reducing and controlling greenhouse emissions (GHG) and to replace fossil fuels in large power plants. Although the use of biomass, originating from forests, could be beneficial, particularly in preventing fires, there are obstacles to achieve a sustainable supply chain of biomass in most European countries. In addition, there are also technical barriers as requirements of biomass combustion may differ from those of coal, which could mean significant retrofitting of existing installations. The combustion behaviour of different biomass materials were studied on a pilot fluidised bed combustor, equipped with two cyclones for particulate matter removal. The gaseous pollutants leaving the stack were sampled under isokinetic conditions for particulate matter, chlorine compounds, heavy metals and dioxins and furans (PCDD/F). The results obtained indicated that the combustion of these materials did not present any operational problem, although for temperatures above 800{sup o}C, bed agglomeration could be observed for all biomass materials studied. Most of the combustion of biomass, contrary to what is observed for coal, takes place in the riser where the temperature was as much as 150{sup o}C above that of the bed. Stable combustion conditions were achieved as well as high combustion efficiency. When compared with the emissions of bituminous coal, the most used fossil fuel, the emissions of CO and SO2 were found to be lower and NOx emissions were similar to those of coal. HCl and PCDD/F could be considerable with biomasses containing high chlorine levels, as in the case of straw. It was observed that the nature of ash could give rise serious operating problems.

  14. Particle fuel bed tests

    International Nuclear Information System (INIS)

    Horn, F.L.; Powell, J.R.; Savino, J.M.

    1985-01-01

    Gas-cooled reactors, using packed beds of small diameter coated fuel particles have been proposed for compact, high-power systems. The particulate fuel used in the tests was 800 microns in diameter, consisting of a thoria kernel coated with 200 microns of pyrocarbon. Typically, the bed of fuel particles was contained in a ceramic cylinder with porous metallic frits at each end. A dc voltage was applied to the metallic frits and the resulting electric current heated the bed. Heat was removed by passing coolant (helium or hydrogen) through the bed. Candidate frit materials, rhenium, nickel, zirconium carbide, and zirconium oxide were unaffected, while tungsten and tungsten-rhenium lost weight and strength. Zirconium-carbide particles were tested at 2000 K in H 2 for 12 hours with no visible reaction or weight loss

  15. INCOME PER BED AS A DETERMINANT OF HOSPITAL’S FINANCIAL LIQUIDITY

    Directory of Open Access Journals (Sweden)

    Agnieszka Bem

    2014-10-01

    Full Text Available Hospitals’ financial condition is very important, in terms of availability and quality of inpatient health care services. Inpatient’s services consume, in Poland, an important part (about 50% of National Health Fund resources, but financial situation of hospitals is difficult and many hospitals report problems with liquidity and solvency. The purpose of this research is to study the relationship between the intensity of care, measured by the annual income per bed, and the static liquidity ratios (current ratio and quick ratio. The research has been conducted on the sample of 138 Polish hospitals, using data covering the period 2009-2011. In order to test research hypotheses, statistical tools have been used (T-Student distribution. The study has shown, that, during analyzed period, liquidity ratios have lowered and the level of financial liquidity is, in case of Polish hospitals, lower than recommended in the literature. The authors also confirmed the existence of the relationship between annual income per bed and liquidity ratios. However, the most important finding is that the relationship between the hospital’s income per bed and financial liquidity ratios is positive only up to a certain level, which has been estimated at about 60,000-70,000 EUR per bed. Above this level further increase in income per bed decreases liquidity ratios. This finding seems to be extremely important for health care managers, which usually strive for the income maximization.

  16. Identification of the western tarnished plant bug (lygus hesperus) olfactory co-receptor orco: expression profile and confirmation of atypical membrane topology

    Science.gov (United States)

    Lygus hesperus (western tarnished plant bug) is an agronomically important pest species of numerous cropping systems. Similar to other insects, a critical component underlying behaviors is the perception and discrimination of olfactory cues. Consequently, the molecular basis of olfaction in this spe...

  17. Effects of morning and night application of Beauveria bassiana strains NI8 and GHA against the tarnished plant bug in cotton

    Science.gov (United States)

    The tarnished plant bug, (TPB), Lygus lineolaris (Palisot de Beauvois), (Hemiptera: Miridae) an important pest of cotton (Gosssypium hirsutum L.) found in the Mississippi Delta is naturally attacked by the entomopathogenic fungus Beauveria bassiana (Balsamo) Vueillemin. In this study, two isolates o...

  18. Production of wood vinegars from coconut shells and additional materials for control of termite workers, Odontotermes sp. and striped mealy bugs, Ferrisia virgata

    Directory of Open Access Journals (Sweden)

    Sunan Wititsiri

    2011-06-01

    Full Text Available Coconut shells and coir are considered as wastes of coconut based products that have not been utilized efficiently.By using these abundant bioresources, which are widely available in Thailand, as raw materials, we were able to producewood vinegars that may be alternatives to termiticides and pesticides. The wood vinegars were obtained from carbonizationprocess using a 200-liter fuel tank as charcoal brazier under temperatures of 300-400°C. In this study, termiticidal and pesticidalactivities of wood vinegars were evaluated against termite workers, Odontotermes sp., and striped mealy bugs, Ferrisiavirgata, using direct contact application. Percent mortalities in the experiments were recorded after 24 hours and correctedfor control mortality with Abbott’s formula. Wood vinegars of 850, 696, and 898 milliliters were produced from coconut shell(wood vinegar A and the mixture of coconut shell and coir (wood vinegar B and the mixture of coconut shell, coir and holybasil (wood vinegar C, respectively. Wood vinegar A exhibited high termiticidal activity against termite workers at a dilutionof 1:50, wood vinegar: sterile water (v/v. By this way, 85% (81.71% corrected mortality of termite workers were killed afterthe 24 hours of test. At a dilution of 1:10, both wood vinegar A and B had exhibited high pesticidal activities against mealybugs, 96% (95.12% corrected mortality of striped mealy bugs were killed by those wood vinegars. In the weakest termiticidaland pesticidal activities, wood vinegar C was able to kill 60% (51.22% corrected mortality of termite workers at a dilution of1:50 within 24 hours. Also it killed 93% (91.89% corrected mortality of striped mealy bugs with a dilution of 1:10 (v/v withinthe same amount of time. Post-hoc comparisons (Tukey test revealed that wood vinegar A possessed the most effectivetermiticidal activity against termite workers. However, a similarity in high pesticidal activity was found among three woodvinegars

  19. Chaotic hydrodynamics of fluidized beds

    Energy Technology Data Exchange (ETDEWEB)

    Van der Stappen, M.L.M. [Unit Process and Systems Engineering, Advanced Manufacturing Technology Group, Unilever Research Laboratorium, Vlaardingen (Netherlands)

    1996-12-31

    The major goals of this thesis are: (1) to develop and evaluate an analysis method based on techniques from non-linear chaos theory to characterize the nonlinear hydrodynamics of gas-solids fluidized beds quantitatively; and (2) to determine the dependence of the chaotic invariants on the operating conditions and investigate how the chaos analysis method can be profitably applied to improve scale-up and design of gas-solids fluidized bed reactors. Chaos theory is introduced in chapter 2 with emphasis on analysis techniques for (experimental) time series, known from literature at the start of this work (1990-1991). In chapter 3, the testing of existing and newly developed techniques on both model and fluidized bed data is described. This leads to the development of the chaos analysis method to analyze measured pressure fluctuations time series of a fluidized bed. Following, in chapter 4, this method is tested and all choices for the parameters are evaluated. The influence of the experimental parameters and external disturbances on the measurements and analysis results is discussed and quantified. The result is a chaos measurement and analysis protocol, which is further used in this work. In chapter 5, the applications to fluidized beds are discussed. It is shown that the entropy is a good measure for the characterization of the dynamical behavior of gas-solids bubbling/slugging fluidized beds. Entropy is applied to characterize the influence of the operating conditions, to assess regime transitions and to analyze dimensionless similar beds of different scale. Quantitative design correlations that relate entropy to the operating parameters (including the bed diameter) are described. Finally, it is discussed how the results of this work might be used in scaling up the chaotic dynamics of fluidized beds. The overall conclusions and outlook from this work are presented in chapter 6. 182 refs.

  20. Comparison of packed bed and fluidized bed membrane reactors for methane reforming

    NARCIS (Netherlands)

    Gallucci, F.; van Sint Annaland, M.; Kuipers, J.A.M.

    2009-01-01

    In this work the performance of different membrane reactor concepts, both fluidized bed and packed bed membrane reactors, have been compared for the reforming of methane for the production of ultra-pure hydrogen. Using detailed theoretical models, the required membrane area to reach a given

  1. Effects of bed-load movement on flow resistance over bed forms

    Indian Academy of Sciences (India)

    Abstract. The effect of bed-load transport on flow resistance of alluvial channels with undulated bed was experimentally investigated. The experiments were carried out in a tilting flume 250mm wide and 12·5m long with glass-sides of rectan- gular cross-section and artificial dune shaped floor that was made from Plexi-glass.

  2. Staged fluidized-bed combustion and filter system

    International Nuclear Information System (INIS)

    Mei, J.S.; Halow, J.S.

    1994-01-01

    A staged fluidized-bed combustion and filter system are described for substantially reducing the quantity of waste through the complete combustion into ash-type solids and gaseous products. The device has two fluidized-bed portions, the first primarily as a combustor/pyrolyzer bed, and the second as a combustor/filter bed. The two portions each have internal baffles to define stages so that material moving therein as fluidized beds travel in an extended route through those stages. Fluidization and movement is achieved by the introduction of gases into each stage through a directional nozzle. Gases produced in the combustor/pyrolyzer bed are permitted to travel into corresponding stages of the combustor/filter bed through screen filters that permit gas flow but inhibit solids flow. Any catalyst used in the combustor/filter bed is recycled. The two beds share a common wall to minimize total volume of the system. A slightly modified embodiment can be used for hot gas desulfurization and sorbent regeneration. Either side-by-side rectangular beds or concentric beds can be used. The system is particularly suited to the processing of radioactive and chemically hazardous waste. 10 figures

  3. Comparative bio-ecological studies among two species of Urentius lace bugs (Hemiptera: Tingidae in Sudan

    Directory of Open Access Journals (Sweden)

    Abdalla Abdelrahim Satti

    2012-06-01

    Full Text Available Among the prevalent lace bugs in Sudan, Urentius hystricellus and Urentius euonymus are important pests of eggplant and pigeon pea, respectively. They attack alternative hosts, but some plants were reported as common hosts for both species. In fact, the identity of these pests and their actual host plants seems to be confusing. Therefore, the main objectives of this work were to; differentiate between such pest species based on certain morpho-biological investigations, verify their hosts’ ranges and study their intra-host distributions and seasonal trends through field surveys and experiments. The results showed clear morphological and biological differences among the two lace bug species. The durations of pre-imaginal stages of U. hystricellus were shorter than those of U. euonymus, while each pest took shorter durations in autumn as compared with winter season. Each pest has its own host range, and no shared hosts were detected, as believed. Hence, the mistaken hosts were corrected and new hosts were added. Such new records included Solanum incanum for U. hystricellus, and two hosts (Chrozophora plicata and Rhynchosia memnonia for U. euonymus. Counts of insects on either leaf sides have revealed variable distributions in different hosts. The seasonal trends of the two pests showed peak populations during autumn and summer seasons. In conclusion, the study made clear distinctions between U. hystricellus and U. euonymus, and gave supportive findings for ecological management.

  4. Stability analysis of the high temperature thermal pebble bed nuclear reactor concept

    International Nuclear Information System (INIS)

    Vondy, D.R.

    1981-02-01

    A study was made of the stability of the high temperature gas-cooled pebble bed core against xenon-driven oscillation. This generic study indicated that a core as large as 3000 MW(t) could be stable. Several aspects present a challenge to analysis including the void space above the pebble bed, the effects of possible control rod configurations, and the temperature feedback contribution. Special methods of analysis were developed in this effort. Of considerable utility was the scheme of including an azimuthal buckling loss term in the neturon balance equations admitting direct solution of the first azimuthal harmonic for a core having azimuthal symmetry. This technique allows the linear stability analysis to be done solving two-dimensional (RZ) problems instead of three-dimensional problems. A scheme for removing the fundamental source contribution was also implemented to allow direct iteration toward the dominant harmonic solution, treating up to three dimensions with diffusion theory

  5. Comparison of cotton square and boll damage and resulting lint and seed loss caused by verde plant bug, Creontiades signatus

    Science.gov (United States)

    Retention of bolls and squares (referred to as fruit retention), boll damage, and resulting cotton lint and seed weight loss were assessed when two (2010) and three (2011) age classes of sympodial fruiting branches with different ages of squares and bolls where exposed to verde plant bug, Creontiade...

  6. Calculation of local bed to wall heat transfer in a fluidized-bed

    International Nuclear Information System (INIS)

    Kilkis, B.I.

    1987-01-01

    Surface to bed heat transfer in a fluidized-bed largely depends upon its local and global hydrodynamical behavior including particle velocity, particle trajectory, gas velocity, and void fraction. In this study, a computer program was developed in order to calculate the local bed to wall heat transfer, by accounting for the local and global instantaneous hydrodynamics of the bed. This is accomplished by utilizing the CHEMFLUB computer program. This information at a given location is interpreted so that the most appropriate heat transfer model is utilized for each time increment. These instantaneous heat transfer coefficient for the given location. Repeating the procedure for different locations, a space average heat transfer coefficient is also calculated. This report briefly summarizes the various heat transfer models employed and gives sample computer results reporting the case study for Mickley - Trilling's experimental set-up. Comparisons with available experimental data and correlations are also provided in order to compare and evaluate the computer results

  7. The effects of temperature, activity and convection on the plastron PO2 of the aquatic bug Aphelocheirus aestivalis (Hemiptera; Aphelocheiridae).

    Science.gov (United States)

    Jones, Karl K; Hetz, Stefan K; Seymour, Roger S

    2017-07-05

    The aquatic bug Aphelocheirus aestivalis (Fabricius 1794) utilises a plastron, a thin bubble layer on the surface of its body to extract O 2 from the water. Millions of tiny hairs keep the bubble from collapsing, enabling the bug to remain submerged indefinitely. The development of fibre optic O 2 -probes has allowed measurements of O 2 pressure (PO 2 ) surrounding the plastron, and within the plastron although only for short periods. Here we developed methods to continuously measure plastron PO 2 , and investigate how it is affected by temperature (15, 20, 25°C), activity, and water circulation. We also made measurements of water PO 2 , temperature and velocity in the field and swimming velocity at the treatment temperatures. Results show that plastron PO 2 is inversely related to temperature, associated with differences in metabolic demand, and that small bouts of activity or changes in water convection result in rapid changes in plastron PO 2 . A model was developed to calculate the conditions under which Aphelocheirus would exist without becoming O 2 -limited in relation to water temperature, PO 2 and boundary layer thickness. This suggests that Aphelocheirus at one of two field sites may have a reduced metabolic scope even in well convected water in association with low PO 2 and moderate temperature, and that in well convected, air-saturated water, bugs may have a reduced metabolic scope where water temperatures are between 20 and 25°C. If exposed to 5kPa PO 2 , Aphelocheirus cannot sustain resting metabolic rate even in well-convected water and would die at temperatures above approximately 25°C. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. A Numerical Model for Trickle Bed Reactors

    Science.gov (United States)

    Propp, Richard M.; Colella, Phillip; Crutchfield, William Y.; Day, Marcus S.

    2000-12-01

    Trickle bed reactors are governed by equations of flow in porous media such as Darcy's law and the conservation of mass. Our numerical method for solving these equations is based on a total-velocity splitting, sequential formulation which leads to an implicit pressure equation and a semi-implicit mass conservation equation. We use high-resolution finite-difference methods to discretize these equations. Our solution scheme extends previous work in modeling porous media flows in two ways. First, we incorporate physical effects due to capillary pressure, a nonlinear inlet boundary condition, spatial porosity variations, and inertial effects on phase mobilities. In particular, capillary forces introduce a parabolic component into the recast evolution equation, and the inertial effects give rise to hyperbolic nonconvexity. Second, we introduce a modification of the slope-limiting algorithm to prevent our numerical method from producing spurious shocks. We present a numerical algorithm for accommodating these difficulties, show the algorithm is second-order accurate, and demonstrate its performance on a number of simplified problems relevant to trickle bed reactor modeling.

  9. A new method to quantify fluidized bed agglomeration in the combustion of biomass fuels

    Energy Technology Data Exchange (ETDEWEB)

    Oehman, M. [Umeaa Univ. (Sweden). Dept. of Chemistry

    1997-12-31

    The present licentiate thesis is a summary and discussion of four papers, dealing with the development, evaluation and use of a new method to quantify bed agglomeration tendencies for biomass fuels. An increased utilization of biomass related fuels has many environmental benefits, but also requires careful studies of potential new problems associated with these fuels such as bed agglomeration/defluidization during combustion and gasification in fluidized beds. From a thorough literature survey, no suitable methods to determine bed agglomeration tendencies of different fuels, fuel combinations or fuels with additives appeared to be available. It therefore seemed of considerable interest to develop a new method for the quantification of fluidized bed agglomeration tendencies for different fuels. A bench scale fluidized bed reactor (5 kW), specially designed to obtain a homogeneous isothermal bed temperature, is used. The method is based on controlled increase of the bed temperature by applying external heat to the primary air and to the bed section walls. The initial agglomeration temperature is determined by on- or off-line principal component analysis of the variations in measured bed temperatures and differential pressures. Samples of ash and bed material for evaluation of agglomeration mechanisms may also be collected throughout the operation. To determine potential effects of all the process related variables on the determined fuel specific bed agglomeration temperature, an extensive sensitivity analysis was performed according to a statistical experimental design. The results showed that the process variables had only relatively small effects on the agglomeration temperature, which could be determined to 899 deg C with a reproducibility of {+-} 5 deg C (STD). The inaccuracy was determined to be {+-} 30 deg C (STD). The method was also used to study the mechanism of both bed agglomeration using two biomass fuels and prevention of bed agglomeration by co

  10. The application of radioactive tracers for determination of bed-load transport in alluvial rivers

    International Nuclear Information System (INIS)

    Thomsen, T.

    1980-01-01

    Radioactive isotopes have been applied for determining the transport rate of bed load in an alluvial river on the basis of: centroid velocity of the tracer particles, size and material-transporting width of mobile layer. These parameters were found by detailed measurements in the field. Computed values were produced on the basis of Engelund and Fredsoee's model on sediment transport and on the propagation of bed forms. When comparing measured and computed values, the difference was about 25%. Finally, the applicability of tracer methods for solving practical problem is discussed. (author)

  11. Occurrence of lace bug Vatiga illudens and Vatiga manihotae (Hemiptera: Tingidae) in Mato Grosso do Sul, midwestern Brazil.

    Science.gov (United States)

    Bellon, Patrícia P; Wengrat, Ana P G S; Kassab, Samir O; Pietrowski, Vanda; Loureiro, Elisângela S

    2012-09-01

    Nymphs and adults of the lace bug (Hemiptera: Tingidae) have been found in cassava crops (Manihot esculenta) in Mato Grosso do Sul State, Brazil. The insects were collected in the field and taken to the laboratory where they were identified based on some morphological traits of the species Vatiga manihotae (Drake) and V. illudens (Drake), which are first reported in the aforementioned state.

  12. Learn about Lead

    Science.gov (United States)

    ... Search Main menu Environmental Topics Air Bed Bugs Chemicals and Toxics Environmental Information by Location Greener Living Health Land, ... it has some beneficial uses, it can be toxic to humans and animals causing of health ... some types of industrial facilities, and past use of lead-based paint ...

  13. Tests of Bed Agglomeration Tendency Using a Rotating Furnace; Roterugn foer bedoemning av sintringsbenaegenhet

    Energy Technology Data Exchange (ETDEWEB)

    Larfeldt, Jenny; Zintl, Frank [TPS Termiska Processer AB, Nykoeping (Sweden)

    2003-08-01

    Bed sintering is a well known problem in fluidised bed boilers. In order to avoid bed sintering the bed material turn over ratio is high which leads a high consumption of bed material. This work aims at developing and evaluating a method for testing the bed agglomeration tendency of a FB bed material by using a rotating furnace. A rotating furnace has been designed and tests have shown that three temperatures describing the increasing agglomeration tendency can be evaluated; TA when several particles stick to each other and to the crucible wall, TB when half of the material sticks to the wall and TC when almost all the material forms a ball in the crucible. Comparison with bed agglomeration tests has shown that TA is between 80 deg C to 130 deg C lower than the bed agglomeration temperature from fluid bed tests. It is shown that TB is closer to the bed agglomeration temperature and finally that the temperature TC is higher than the bed agglomeration temperature. It is concluded that in the rotating furnace sticking of particles is visualised early, and that this sticking will not cause defluidisation of the bed until more than half of the material in the crucible is sticky. Repeated tests has been performed at a heating rate of 5 deg/minute and a rotating speed of 12 rpm and a furnace inclination of 20 deg was found to give distinct results in the evaluation. The evaluation has shown to be reproducible at lower temperatures. At higher temperatures, around 1,000 deg C, the evaluation was complicated by a poor picture quality which probably can be improved by proper cooling of the camera. It has also been shown that sticking of material in the rotating furnace could be detected at relatively low temperatures of 750 deg C that disappeared at higher temperatures. This is likely to be explained by melting salts that evaporates as temperature increase. At even higher temperatures the sticking reappeared until a ball was formed in the crucible. The latter sticking is

  14. Effect of a Central Graphite Column on a Pebble Flow in a Pebble Bed Core

    International Nuclear Information System (INIS)

    In, W. K.; Lee, W. J.; Chang, J. H.

    2006-01-01

    A pebble bed reactor(PBR) uses coated fuel particles embedded in spherical graphite fuel pebbles. The fuel pebbles flow down through the core during an operation. The pebble bed core is configured as cylindrical or annular depending on the reactor power. It is well known that an annular core can increase a cores' thermal power. The annular inner core zone is typically filled with movable graphite balls or a fixed graphite column. The first problem with this conventional annular core is that it is difficult to maintain a boundary between the central graphite ball zone and the outer fuel zone. The second problem is that it is expensive to replace the central fixed graphite column after several tens of years of reactor operation. In order to resolve these problems, a PBR with a central graphite column in a low core is invented. This paper presents the effect of the central graphite column on a pebble flow by using the computational fluid dynamics(CFD) code, CFX-10

  15. An Apparatus for Bed Material Sediment Extraction From Coarse River Beds in Large Alluvial Rivers

    Science.gov (United States)

    Singer, M. B.; Adam, H.; Cooper, J.; Cepello, S.

    2005-12-01

    Grain size distributions of bed material sediment in large alluvial rivers are required in applications ranging from habitat mapping, calibration of sediment transport models, high resolution sediment routing, and testing of existing theories of longitudinal and cross steam sediment sorting. However, characterizing bed material sediment from coarse river beds is hampered by difficulties in sediment extraction, a challenge that is generally circumvented via pebble counts on point bars, even though it is unclear whether the bulk grain size distribution of bed sediments is well represented by pebble counts on bars. We have developed and tested a boat-based sampling apparatus and methodology for extracting bulk sediment from a wide range of riverbed materials. It involves the use of a 0.4 x 0.4 x 0.2 meter stainless steel toothed sampler, called the Cooper Scooper, which is deployed from and dragged downstream by the weight of a jet boat. The design is based on that of a river anchor such that a rotating center bar connected to a rope line in the boat aligns the sampler in the downstream direction, the teeth penetrate the bed surface, and the sampler digs into the bed. The sampler is fitted with lead weights to keep it from tipping over. The force of the sampler `biting' into the bed can be felt on the rope line held by a person in the boat at which point they let out slack. The boat then motors to the spot above the embedded sampler, which is hoisted to the water surface via a system of pulleys. The Cooper Scooper is then clipped into a winch and boom assembly by which it is brought aboard. This apparatus improves upon commonly used clamshell dredge samplers, which are unable to penetrate coarse or mixed bed surfaces. The Cooper Scooper, by contrast, extracts statistically representative bed material sediment samples of up to 30 kilograms. Not surprisingly, the sampler does not perform well in very coarse or armored beds (e.g. where surface material size is on the

  16. A mathematical model for supplying air-cooling for a building using a packed bed

    Energy Technology Data Exchange (ETDEWEB)

    Marewo, G.T. [Zimbabwe Univ., Mathematics Dept., Harare (Zimbabwe); Henwood, D.J. [School of Computing and Mathematical Sciences, Brighton (United Kingdom)

    2006-01-15

    The cooling system at the Harare International School uses a packed bed system for storing the coldness of the night-time to be used later for day-time air-conditioning. A two-phase mathematical model is described for the packed bed which includes heat dispersion in the fluid, and heat loss to the environment. This is in contrast to other studies, where at least one of these terms is neglected to simplify the mathematical model. A numerical method for obtaining a solution is proposed and implemented. Using measured inlet temperatures, the measured and predicted outlet temperatures of the bed show good trend agreement. The differences in detail are examined through sensitivity analyses for both the heat convection transfer and air velocity. It is apparent that adjusting these parameters can increase the agreement between the predicted and measured data. A parametric study for heat storage with various materials and bed sizes is given, which indicates how the code may be used as a tool for improving design and operational parameters. Practical application: A mathematical model of a packed bed is described; the bed is made up of fluid flowing over solid material with heat interchange between the two. The solid material is idealized as spheres and the fluid temperature is assumed uniform in a cross-section of the bed. The model includes heat interchange between the bed and its surrounding environment and allows for time varying fluid velocity. The input data is the inlet temperature to the bed, which may be measured. The comparison with measured data may be helpful to anyone attempting to develop and test a similar model. The sensitivity tests give an understanding of the significance of some of the parameters involved. The Appendix gives a mathematical statement of the problem and an outline of an approach to developing computer code for a numerical solution. (Author)

  17. Hypothetical operation model for the multi-bed system of the Tritium plant based on the scheduling approach

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae-Uk, E-mail: eslee@dongguk.edu [Department of Chemical Engineering, Pohang University of Science and Technology, San 31, Hyoja-Dong, Pohang 790-784 (Korea, Republic of); Chang, Min Ho; Yun, Sei-Hun [National Fusion Research Institute, 169-148-gil Kwahak-ro, Yusong-gu, Daejon 34133 (Korea, Republic of); Lee, Euy Soo [Department of Chemical & Biochemical Engineering, Dongguk University, Seoul 100-715 (Korea, Republic of); Lee, In-Beum [Department of Chemical Engineering and Graduate School of Engineering Mastership, Pohang University of Science and Technology, San 31, Hyoja-Dong, Pohang 790-784 (Korea, Republic of); Lee, Kun-Hong [Department of Chemical Engineering, Pohang University of Science and Technology, San 31, Hyoja-Dong, Pohang 790-784 (Korea, Republic of)

    2016-11-01

    Highlights: • We introduce a mathematical model for the multi-bed storage system in the tritium plant. • We obtain details of operation by solving the model. • The model assesses diverse operation scenarios with respect to risk. - Abstract: In this paper, we describe our hypothetical operation model (HOM) for the multi-bed system of the storage and delivery system (SDS) of the ITER tritium plant. The multi-bed system consists of multiple getter beds (i.e., for batch operation) and buffer vessels (i.e., for continuous operation). Our newly developed HOM is formulated as a mixed-integer linear programming (MILP) model and has been extensively investigated to optimize chemical and petrochemical production planning and scheduling. Our model determines the timing, duration, and size of tasks corresponding to each set of equipment. Further, inventory levels for each set of equipment are calculated. Our proposed model considers the operation of one cycle of one set of getter beds and is implemented and assessed as a case study problem.

  18. Apparatus and process for controlling fluidized beds

    Science.gov (United States)

    Rehmat, Amirali G.; Patel, Jitendra G.

    1985-10-01

    An apparatus and process for control and maintenance of fluidized beds under non-steady state conditions. An ash removal conduit is provided for removing solid particulates from a fluidized bed separate from an ash discharge conduit in the lower portion of the grate supporting such a bed. The apparatus and process of this invention is particularly suitable for use in ash agglomerating fluidized beds and provides control of the fluidized bed before ash agglomeration is initiated and during upset conditions resulting in stable, sinter-free fluidized bed maintenance.

  19. Fluidized bed boiler feed system

    Science.gov (United States)

    Jones, Brian C.

    1981-01-01

    A fluidized bed boiler feed system for the combustion of pulverized coal. Coal is first screened to separate large from small particles. Large particles of coal are fed directly to the top of the fluidized bed while fine particles are first mixed with recycled char, preheated, and then fed into the interior of the fluidized bed to promote char burnout and to avoid elutriation and carryover.

  20. Neurohormones implicated in the control of Malpighian tubule secretion in plant sucking Heteropterans: The stink bugs Acrosternum hilare and Nezara viridula

    Science.gov (United States)

    Plant sucking heteropteran bugs feed regularly on small amounts of K+rich plant material, in contrast to their hematophagous relatives which imbibe large volumes of Na+-rich blood. It was anticipated that this would be reflected in the endocrine control of MT secretion. To explore this, neuroendocri...

  1. Structural polarity and dynamics of male germline stem cells in an insect (milkweed bug Oncopeltus fasciatus).

    Science.gov (United States)

    Dorn, David C; Dorn, August

    2008-01-01

    Knowing the structure opens a door for a better understanding of function because there is no function without structure. Male germline stem cells (GSCs) of the milkweed bug (Oncopeltus fasciatus) exhibit a very extraordinary structure and a very special relationship with their niche, the apical cells. This structural relationship is strikingly different from that known in the fruit fly (Drosophila melanogaster) -- the most successful model system, which allowed deep insights into the signaling interactions between GSCs and niche. The complex structural polarity of male GSCs in the milkweed bug combined with their astonishing dynamics suggest that cell morphology and dynamics are causally related with the most important regulatory processes that take place between GSCs and niche and ensure maintenance, proliferation, and differentiation of GSCs in accordance with the temporal need of mature sperm. The intricate structure of the GSCs of the milkweed bug (and probably of some other insects, i.e., moths) is only accessible by electron microscopy. But, studying singular sections through the apical complex (i.e., GSCs and apical cells) is not sufficient to obtain a full picture of the GSCs; especially, the segregation of projection terminals is not tangible. Only serial sections and their overlay can establish whether membrane ingrowths merely constrict projections or whether a projection terminal is completely cut off. To sequence the GSC dynamics, it is necessary to include juvenile stages, when the processes start and the GSCs occur in small numbers. The fine structural analysis of segregating projection terminals suggests that these terminals undergo autophagocytosis. Autophagosomes can be labeled by markers. We demonstrated acid phosphatase and thiamine pyrophosphatase (TPPase). Both together are thought to identify autophagosomes. Using the appropriate substrate of the enzymes and cerium chloride, the precipitation of electron-dense cerium phosphate granules

  2. Fluidized bed incinerator development

    International Nuclear Information System (INIS)

    Ziegler, D.L.; Johnson, A.J.

    1976-01-01

    A fluidized bed incinerator is being developed for burning rad contaminated solid and liquid waste materials. In situ neutralization of acid gases by the bed material, catalytic afterburning, and gas filtration are used to produce a clean flue gas without the use of aqueous scrubbing

  3. Petrology and geochemistry of samples from bed-contact zones in Tunnel Bed 5, U12g-Tunnel, Nevada Test Site

    International Nuclear Information System (INIS)

    Connolly, J.R.; Keil, K.; Mansker, W.L.; Allen, C.C.; Husler, J.; Lowy, R.; Fortney, D.R.; Lappin, A.R.

    1984-10-01

    This report summarizes the detailed geologic characterization of samples of bed-contact zones and surrounding nonwelded bedded tuffs, both within Tunnel Bed 5, that are exposed in the G-Tunnel complex beneath Rainier Mesa on the Nevada Test Site (NTS). Original planning studies treated the bed-contact zones in Tunnel Bed 5 as simple planar surfaces of relatively high permeability. Detailed characterization, however, indicates that these zones have a finite thickness, are depositional in origin, vary considerably over short vertical and horizontal distances, and are internally complex. Fluid flow in a sequence of nonwelded zeolitized ash-flow or bedded tuffs and thin intervening reworked zones appears to be a porous-medium phenomenon, regardless of the presence of layering. There are no consistent differences in either bulk composition or detailed mineralogy between bedded tuffs and bed-contact zones in Tunnel Bed 5. Although the original bulk composition of Tunnel Bed 5 was probably peralkaline, extensive zeolitization has resulted in a present peraluminous bulk composition of both bedded tuffs and bed-contact zones. The major zeolite present, clinoptilolite, is intermediate (Ca:K:Na = 26:35:39) and effectively uniform in composition. This composition is similar to that of clinoptilolite from the tuffaceous beds of Calico Hills above the static water level in hole USW G-1, but somewhat different from that reported for zeolites from below the static water level in USW G-2. Tunnel Bed 5 also contains abundant hydrous manganese oxides. The similarity in composition of the clinoptilolites from Tunnel Bed 5 and those above the static water level at Yucca Mountain indicates that many of the results of nuclide-migration experiments in Tunnel Bed 5 would be transferrable to zeolitized nonwelded tuffs above the static water level at Yucca Mountain

  4. Theoretical comparison of packed bed and fluidized bed membrane reactors for methane reforming

    NARCIS (Netherlands)

    Gallucci, F.; van Sint Annaland, M.; Kuipers, J.A.M.

    2010-01-01

    In this theoretical work the performance of different membrane reactor concepts, both fluidized bed and packed bed membrane reactors, has been compared for ultra-pure hydrogen production via methane reforming. Using detailed theoretical models, the required membrane area to reach a given conversion

  5. Atmospheric Fluidized Bed Combustion testing of North Dakota lignite

    Energy Technology Data Exchange (ETDEWEB)

    Goblirsch, G; Vander Molen, R H; Wilson, K; Hajicek, D

    1980-05-01

    The sulfur retention by the inherent alkali, and added limestone sorbent, perform about the same and are reasonably predictable within a range of about +-10% retention by application of alkali to sulfur ratio. Temperature has a substantial effect on the retention of sulfur by the inherent alkali or limestone. The temperature effect is not yet fully understood but it appears to be different for different coals and operational conditions. The emission of SO/sub 2/ from the fluid bed burning the Beulah lignite sample used for these tests can be controlled to meet or better the current emission standards. The injection of limestone to an alkali-to-sulfur molar ratio of 1.5 to 1, should lower the SO/sub 2/ emissions below the current requirement of 0.6 lb SO/sub 2//10/sup 6/ Btu to 0.4 lb SO/sub 2//10/sup 6/ Btu, a safe 33% below the standard. Agglomeration of bed material, and consequent loss of fluidization quality can be a problem when burning high sodium lignite in a silica bed. There appears, however, to be several ways of controlling the problem including the injection of calcium compounds, and careful control of operating conditions. The heat transfer coefficients measured in the CPC and GFETC tests are comparable to data obtained by other researchers, and agree reasonably well with empirical conditions. The NO/sub x/ emissions measured in all of the tests on Beulah lignite are below the current New Source Performance Standard of 0.5 lb NO/sub 2//10/sup 6/ Btu input. Combustion efficiencies for the Beulah lignite are generally quite high when ash recycle is being used. Efficiencies in the range of 98% to 99%+ have been measured in all tests using this fuel.

  6. Fluid-bed process for SYNROC production

    International Nuclear Information System (INIS)

    Ackerman, F.J.; Grens, J.Z.; Ryerson, F.J.; Hoenig, C.L.; Bazan, F.; Peters, P.E.; Smith, R.; Campbell, J.H.

    1983-01-01

    SYNROC is a titanate-based ceramic waste developed for the immobilization of high-level nuclear reactor waste. Lawrence Livermore National Laboratory (LLNL) has investigated a fluid-bed technique for the large-scale production of SYNROC precursor powders. Making SYNROC in a fluid bed permits slurry drying, calcination and reduction-oxidation reactions to be carried out in a single unit. We present the results of SYNROC fluid-bed studies from two fluid-bed units 10 cm in diameter: an internally heated fluid-bed unit developed by Exxon Idaho and an externally heated unit constructed at LLNL. Bed operation over a range of temperatures, feed rates, fluidizing rates, and redox conditions indicate that SYNROC powders of a high density and a uniform particle size can be produced. These powders facilitate the densification step and yield dense ceramics (greater than 95% theoretical density) with well-developed phases and low leaching rates

  7. Method for the combustion of a gas, in fixed bed, with an oxidized solid and associated installation

    OpenAIRE

    Abanades García, Juan Carlos; Fernández García, José Ramón

    2014-01-01

    [EN] The present invention pertains to the field of the generation of energy from combustible gases, incorporating the capture of carbon dioxide for use or permanent storage and, specifically relates to cyclical methods of gas combustion with oxidized solids (chemical looping processes), in fixed bed, for solving the problem of controlling temperature in the combustion of gaseous fuels in fixed beds of metal oxides operating at high pressures, and also the associated installation.

  8. 76 FR 69728 - SFIREG Full Committee; Notice of Public Meeting

    Science.gov (United States)

    2011-11-09

    ...; telephone number: (703) 305-5561; fax number: (703) 305-1850; email address: [email protected] or Grier...; fax: (302) 422-2435; email address: Stayton, Grier at [email protected] . SUPPLEMENTARY... holidays. The Docket Facility telephone number is (703) 305-5805. II. Tentative Agenda Topics 1. Bed Bug IP...

  9. Clinical evaluation of an automated turning bed.

    Science.gov (United States)

    Melland, H I; Langemo, D; Hanson, D; Olson, B; Hunter, S

    1999-01-01

    The purposes of this study were to assess client comfort and sleep quality, client physiologic response (skin and respiratory status), the effect on the need for caregiver assistance, and cost when using an automated turning bed. Nonexperimental, evaluative study. Twenty-four adult home or long-term care resident subjects who had a degenerative disease, spinal cord injury, stroke, cerebral palsy, or back surgery. Each subject agreed to use the automated turning bed for four weeks. Researchers completed a demographic survey and skin assessment, and assessed each subject for pressure ulcer risk and for the need of assistance of a care giver for turning before and after the four weeks of using the turning bed. Subjects rated the turning bed in terms of comfort and sleep quality. Subjects rated the turning bed as more comfortable than their own bed and expressed satisfaction at the pain relief attained when on the turning bed. While using the turning bed, there was a significant improvement in sleep quality. No skin breakdown or deterioration in respiratory status occurred. Fewer subjects required the assistance of a caregiver for turning when on the turning bed. This automated turning bed shows great promise in meeting a need for patients with limited mobility whether they are homebound or in a residential community. Future studies that further investigate use of the turning bed for postoperative back patients while still in the acute care setting are indicated. Replicative studies with a larger sample size are also indicated.

  10. Soybean resistance to stink bugs (Nezara viridula and Piezodorus guildinii) increases with exposure to solar UV-B radiation and correlates with isoflavonoid content in pods under field conditions.

    Science.gov (United States)

    Zavala, Jorge A; Mazza, Carlos A; Dillon, Francisco M; Chludil, Hugo D; Ballaré, Carlos L

    2015-05-01

    Solar UV-B radiation (280-315 nm) has a significant influence on trophic relationships in natural and managed ecosystems, affecting plant-insect interactions. We explored the effects of ambient UV-B radiation on the levels of herbivory by stink bugs (Nezara viridula and Piezodorus guildinii) in field-grown soybean crops. The experiments included two levels of UV-B radiation (ambient and attenuated UV-B) and four soybean cultivars known to differ in their content of soluble leaf phenolics. Ambient UV-B radiation increased the accumulation of the isoflavonoids daidzin and genistin in the pods of all cultivars. Soybean crops grown under attenuated UV-B had higher numbers of unfilled pods and damaged seeds than crops grown under ambient UV-B radiation. Binary choice experiments with soybean branches demonstrated that stink bugs preferred branches of the attenuated UV-B treatment. We found a positive correlation between percentage of undamaged seeds and the contents of daidzin and genistin in pods. Our results suggest that constitutive and UV-B-induced isoflavonoids increase plant resistance to stink bugs under field conditions. © 2014 John Wiley & Sons Ltd.

  11. The combustion of low calorific value fuels (oil shale) by using fluidized bed combustor

    International Nuclear Information System (INIS)

    Azzam, S.M.

    1993-01-01

    The present work reports an experimental data for combustion of oil-shale in a fluidized bed combustor. The experimental set up was designed for the combustion of low calorific value fuel such as oil-shale to facilitate the variation of many parameters over a wide operating range. A cold run was firstly conducted to study the fluidization parameters. Fluidization experiment were made with different sized quartiz particles. Minimum fluidization velocities and other fluidization characteristics were determined at room temperature. Secondary a hot run was started, first studying the combustion of 'LPG' in a fluidized bed as a starting process, then studying the combustion if oil-shale with different flow rates. The experimetal results are promising and give rise to hopes that this valuable deposit can be used as a fuel source and can be burned sucessfully in a fluidized bed combustor. This study had prooved that utilization of oil-shale a fuel source is no more a complicated technical problem, this opens the way for power generation using fluidized bed combustors. (author). 17 refs., 32 figs., 3 tabs

  12. The combustion of low calorific value fuels (oil shale) by using fluidized bed combustor

    Energy Technology Data Exchange (ETDEWEB)

    Azzam, S M

    1994-12-31

    The present work reports an experimental data for combustion of oil-shale in a fluidized bed combustor. The experimental set up was designed for the combustion of low calorific value fuel such as oil-shale to facilitate the variation of many parameters over a wide operating range. A cold run was firstly conducted to study the fluidization parameters. Fluidization experiment were made with different sized quartiz particles. Minimum fluidization velocities and other fluidization characteristics were determined at room temperature. Secondary a hot run was started, first studying the combustion of `LPG` in a fluidized bed as a starting process, then studying the combustion if oil-shale with different flow rates. The experimetal results are promising and give rise to hopes that this valuable deposit can be used as a fuel source and can be burned sucessfully in a fluidized bed combustor. This study had prooved that utilization of oil-shale a fuel source is no more a complicated technical problem, this opens the way for power generation using fluidized bed combustors. (author). 17 refs., 32 figs., 3 tabs.

  13. Predicting fractional bed load transport rates: Application of the Wilcock‐Crowe equations to a regulated gravel bed river

    Science.gov (United States)

    Gaeuman, David; Andrews, E.D.; Krause, Andreas; Smith, Wes

    2009-01-01

    Bed load samples from four locations in the Trinity River of northern California are analyzed to evaluate the performance of the Wilcock‐Crowe bed load transport equations for predicting fractional bed load transport rates. Bed surface particles become smaller and the fraction of sand on the bed increases with distance downstream from Lewiston Dam. The dimensionless reference shear stress for the mean bed particle size (τ*rm) is largest near the dam, but varies relatively little between the more downstream locations. The relation between τ*rm and the reference shear stresses for other size fractions is constant across all locations. Total bed load transport rates predicted with the Wilcock‐Crowe equations are within a factor of 2 of sampled transport rates for 68% of all samples. The Wilcock‐Crowe equations nonetheless consistently under‐predict the transport of particles larger than 128 mm, frequently by more than an order of magnitude. Accurate prediction of the transport rates of the largest particles is important for models in which the evolution of the surface grain size distribution determines subsequent bed load transport rates. Values of τ*rm estimated from bed load samples are up to 50% larger than those predicted with the Wilcock‐Crowe equations, and sampled bed load transport approximates equal mobility across a wider range of grain sizes than is implied by the equations. Modifications to the Wilcock‐Crowe equation for determining τ*rm and the hiding function used to scale τ*rm to other grain size fractions are proposed to achieve the best fit to observed bed load transport in the Trinity River.

  14. How-To-Do-It: Snails, Pill Bugs, Mealworms, and Chi-Square? Using Invertebrate Behavior to Illustrate Hypothesis Testing with Chi-Square.

    Science.gov (United States)

    Biermann, Carol

    1988-01-01

    Described is a study designed to introduce students to the behavior of common invertebrate animals, and to use of the chi-square statistical technique. Discusses activities with snails, pill bugs, and mealworms. Provides an abbreviated chi-square table and instructions for performing the experiments and statistical tests. (CW)

  15. A new vibration isolation bed stage with magnetorheological dampers for ambulance vehicles

    International Nuclear Information System (INIS)

    Chae, Hee Dong; Choi, Seung-Bok

    2015-01-01

    The vibration experienced in an ambulance can lead to secondary injury to a patient and discourage a paramedic from providing emergency care. In this study, with the goal of resolving this problem, a new vibration isolation bed stage associated with magnetorheological (MR) dampers is proposed to ensure ride quality as well as better care for the patient while he/she is being transported. The bed stage proposed in this work can isolate vibrations in the vertical, rolling and pitching directions to reflect the reality that occurs in the ambulance. Firstly, an appropriate-sized MR damper is designed based on the field-dependent rheological properties of MR fluid, and the damping force characteristics of a MR damper are evaluated as a function of the current. A mechanical model of the proposed vibration isolation bed stage is then established to derive the governing equations of motion. Subsequently, a sliding mode controller is formulated to control the vibrations caused from the imposed excitation signals; those signals are directly measured using a real ambulance subjected to bump-and-curve road conditions. Using the controller based on the dynamic motion of the bed stage, the vibration control performance is evaluated in both the vertical and pitch directions. It is demonstrated that the magnitude of the vibration in the patient compartment of the ambulance can be significantly reduced by applying an input current to the MR dampers installed for the new bed stage. (technical note)

  16. DNA profiling of trace DNA recovered from bedding.

    Science.gov (United States)

    Petricevic, Susan F; Bright, Jo-Anne; Cockerton, Sarah L

    2006-05-25

    Trace DNA is often detected on handled items and worn clothing examined in forensic laboratories. In this study, the potential transfer of trace DNA to bedding by normal contact, when an individual sleeps in a bed, is examined. Volunteers slept one night on a new, lower bed sheet in their own bed and one night in a bed foreign to them. Samples from the sheets were collected and analysed by DNA profiling. The results indicate that the DNA profile of an individual can be obtained from bedding after one night of sleeping in a bed. The DNA profile of the owner of the bed could also be detected in the foreign bed experiments. Since mixed DNA profiles can be obtained from trace DNA on bedding, caution should be exercised when drawing conclusions from DNA profiling results obtained from such samples. This transfer may have important repercussions in sexual assault investigations.

  17. Utility of Recycled Bedding for Laboratory Rodents

    OpenAIRE

    Miyamoto, Toru; Li, Zhixia; Kibushi, Tomomi; Okano, Shinya; Yamasaki, Nakamichi; Kasai, Noriyuki

    2009-01-01

    Animal facilities generate a large amount of used bedding containing excrement as medical waste. We developed a recycling system for used bedding that involves soft hydrothermal processing. In this study, we examined the effects of bedding type on growth, hematologic and serum biochemical values, and organ weights of female and male mice reared on either recycled or fresh bedding from 3 to 33 wk of age. Neither growth nor physiology differed between mice housed on recycled bedding compared wi...

  18. Bed-To-Wall Heat Transfer in a Supercritical Circulating Fluidised Bed Boiler

    Directory of Open Access Journals (Sweden)

    Błaszczuk Artur

    2014-06-01

    Full Text Available The purpose of this work is to find a correlation for heat transfer to walls in a 1296 t/h supercritical circulating fluidised bed (CFB boiler. The effect of bed-to-wall heat transfer coefficient in a long active heat transfer surface was discussed, excluding the radiation component. Experiments for four different unit loads (i.e. 100% MCR, 80% MCR, 60% MCR and 40% MCR were conducted at a constant excess air ratio and high level of bed pressure (ca. 6 kPa in each test run. The empirical correlation of the heat transfer coefficient in a large-scale CFB boiler was mainly determined by two key operating parameters, suspension density and bed temperature. Furthermore, data processing was used in order to develop empirical correlation ranges between 3.05 to 5.35 m·s-1 for gas superficial velocity, 0.25 to 0.51 for the ratio of the secondary to the primary air, 1028 to 1137K for bed temperature inside the furnace chamber of a commercial CFB boiler, and 1.20 to 553 kg·m-3 for suspension density. The suspension density was specified on the base of pressure measurements inside the boiler’s combustion chamber using pressure sensors. Pressure measurements were collected at the measuring ports situated on the front wall of the combustion chamber. The obtained correlation of the heat transfer coefficient is in agreement with the data obtained from typical industrial CFB boilers.

  19. Using Passive Polyethylene Samplers to Evaluate Chemical Activities Controlling Fluxes and Bioaccumulation of Organic Contaminants in Bed Sediments

    Science.gov (United States)

    2010-11-01

    often yielding uncertain information regarding the degree of hazard and the spatial extent of the problem. Subsequent remediation commonly involves...suited to sampling organic contaminants across bed-water interfaces and down into the sediment bed. The methodology must yield data that are more...surrogate standards were Soxhlet extracted for 24 hr using 450 mL of dichloromethane. Extracts were reduced to approximately 10 mL using the rotary

  20. Bed Load Variability and Morphology of Gravel Bed Rivers Subject to Unsteady Flow: A Laboratory Investigation

    Science.gov (United States)

    Redolfi, M.; Bertoldi, W.; Tubino, M.; Welber, M.

    2018-02-01

    Measurement and estimation of bed load transport in gravel bed rivers are highly affected by its temporal fluctuations. Such variability is primarily driven by the flow regime but is also associated with a variety of inherent channel processes, such as flow turbulence, grain entrainment, and bed forms migration. These internal and external controls often act at comparable time scales, and are therefore difficult to disentangle, thus hindering the study of bed load variability under unsteady flow regime. In this paper, we report on laboratory experiments performed in a large, mobile bed flume where typical hydromorphological conditions of gravel bed rivers were reproduced. Data from a large number of replicated runs, including triangular and square-wave hydrographs, were used to build a statistically sound description of sediment transport processes. We found that the inherent variability of bed load flux strongly depends on the sampling interval, and it is significantly higher in complex, wandering or braided channels. This variability can be filtered out by computing the mean response over the experimental replicates, which allows us to highlight two distinctive phenomena: (i) an overshooting (undershooting) response of the mean bed load flux to a sudden increase (decrease) of discharge, and (ii) a clockwise hysteresis in the sediment rating curve. We then provide an interpretation of these findings through a conceptual mathematical model, showing how both phenomena are associated with a lagging morphological adaptation to unsteady flow. Overall, this work provides basic information for evaluating, monitoring, and managing gravel transport in morphologically active rivers.

  1. Use of bed nets and factors that influence bed net use among Jinuo Ethnic Minority in southern China.

    Science.gov (United States)

    Xu, Jian-wei; Liao, Yuan-mei; Liu, Hui; Nie, Ren-hua; Havumaki, Joshua

    2014-01-01

    Insecticide-treated nets (ITNs) are an integral part of vector control recommendations for malaria elimination in China. This study investigated the extent to which bed nets were used and which factors influence bed net use among Jinuo Ethnic Minority in China-Myanmar-Laos border areas. This study combined a quantitative household questionnaire survey and qualitative semi-structured in-depth interviews (SDI). Questionnaires were administered to 352 heads of households. SDIs were given to 20 key informants. The bed net to person ratio was 1∶2.1 (i.e., nearly one net for every two people), however only 169 (48.0%) households owned at least one net and 623 (47.2%) residents slept under bed nets the prior night. The percentages of residents who regularly slept under nets (RSUN) and slept under nets the prior night (SUNPN) were similar (48.0% vs. 47.2%, P>0.05), however the percentage correct use of nets (CUN) was significantly lower (34.5%, Pcash income per person (ACIP) was an independent factor that influenced bed net use (PHigh bed net availability does not necessarily mean higher coverage or bed net use. Household income, house type and knowledge of the ability of bed nets to prevent malaria are all independent factors that influence bed net use among Jinuo Ethnic Minority.

  2. Numerical calculation of wall-to-bed heat transfer coefficients in gas-fluidized beds

    NARCIS (Netherlands)

    Kuipers, J.A.M.; Prins, W.; van Swaaij, W.P.M.

    1992-01-01

    A computer model for a hot gas-fluidized bed has been developed. The theoretical description is based on a two-fluid model (TFM) approach in which both phases are considered to be continuous and fully interpenetrating. Local wall-to-bed heat-transfer coefficients have been calculated by the

  3. Field evaluation on the lethal effect of Beauveria bassiana strains NI8 and GHA against the tarnished plant bug in cotton

    Science.gov (United States)

    The entomopathogenic fungus Beauveria bassiana Delta native strain NI8 have shown great potential for the management of tarnished plant bug adults when compared with the commercial strain GHA. Population of L lineolaris in cages was reduced by 50% 10 days after application of the NI8 native strain a...

  4. Halophilanema prolata n. gen., n. sp. (Nematoda: Allantonematidae, a parasite of the intertidal bug, Saldula laticollis (Reuter(Hemiptera: Saldidae on the Oregon coast

    Directory of Open Access Journals (Sweden)

    Poinar George O

    2012-02-01

    Full Text Available Abstract Background It is rare to find terrestrial nematode lineages parasitizing arthropods inhabiting the intertidal or littoral zone of the oceans. During an ecological study along the Oregon dunes, an allantonematid nematode (Tylenchomorpha: Allantonematidae was discovered parasitizing the intertidal shore bug, Saldula laticollis (Reuter(Hemiptera: Saldidae. This shore bug is adapted to an intertidal environment and can survive short periods of submergence during high tides. The present study describes the nematode parasite and discusses aspects of its development, ecology and evolution. Methods Adults and last instar nymphs of S. laticollis (Hemiptera: Saldidae were collected from the high intertidal zone among clumps of Juncus L. (Juncaceae plants at Waldport, Oregon on October 3, 2011. The bugs were dissected in 1% saline solution and the nematodes killed in 1% Ringers solution and immediately fixed in 5% formalin (at 20°C. Third stage juveniles removed from infected hosts were maintained in 1% saline solution until they matured to the adult stage, molted and mated. Results Halophilanema prolata n. gen., n. sp. (Nematoda: Allantonematidae is described from last instar nymphs and adults of the intertidal bug, Saldula laticollis on the Oregon coast. The new genus can be distinguished from other genera in the Allantonematidae by a stylet lacking basal knobs in both sexes, an excretory pore located behind the nerve ring, ribbed spicules, a gubernaculum, the absence of a bursa and the elongate-tubular shape of the ovoviviparous parasitic females. Studies of the organogenesis of Halophilanema showed development to third stage juveniles in the uterus of parasitic females. Maturation to the free-living adults and mating occurred in the environment. The incidence of infection of S. laticollis ranged from 0% to 85% depending on the microhabitat in the intertidal zone. Conclusions Based on the habitat and morphological characters, it is proposed

  5. VA National Bed Control System

    Data.gov (United States)

    Department of Veterans Affairs — The VA National Bed Control System records the levels of operating, unavailable and authorized beds at each VAMC, and it tracks requests for changes in these levels....

  6. Tritium measurement technique using ''in-bed'' calorimetry

    International Nuclear Information System (INIS)

    Klein, J.E.; Mallory, M.K.; Nobile, A. Jr.

    1991-01-01

    One of the new technologies that has been introduced to the Savannah River Site (SRS) is the production scale use of metal hydride technology to store, pump, and compress hydrogen isotopes. For tritium stored in metal hydride storage beds, a unique relationship does not exist between the amount of tritium in the bed and the pressure-volume-temperature properties of the hydride material. Determining the amount of tritium in a hydride bed after desorbing the contents of the bed to a tank and performing pressure, volume, temperature, and composition (PVTC) measurements is not practical due to long desorption/absorption times and the inability to remove tritium ''heels'' from the metal hydride materials under normal processing conditions. To eliminate the need to remove tritium from hydride storage beds for measurement purposes, and ''in-bed'' tritium calorimetric measurement technique has been developed. The steady-state temperature rise of a gas stream flowing through a jacketed metal hydride storage bed is measured and correlated with power input to electric heaters used to simulate the radiolytic power generated by the decay of tritium to 3 He. Temperature rise results for prototype metal hydride storage beds and the effects of using different gases in the bed are shown. Linear regression results shows that for 95% confidence intervals, temperature rise measurements can be obtained in 14 hours and have an accuracy of ±1.6% of a tritium filled hydride storage bed

  7. Water scorpions (Heteroptera, Nepidae) and giant water bugs (Heteroptera, Belostomatidae): Sources of new members of the adipokinetic hormone/red pigment-concentrating hormone family

    Czech Academy of Sciences Publication Activity Database

    Gäde, G.; Šimek, Petr; Marco, H. G.

    2007-01-01

    Roč. 28, č. 7 (2007), s. 1359-1367 ISSN 0196-9781 Grant - others:Natioanl Research Foundation(ZA) 2053396 Institutional research plan: CEZ:AV0Z50070508 Keywords : Insects * Heteroptera * Water bugs Subject RIV: ED - Physiology Impact factor: 2.368, year: 2007

  8. Experimental and theoretical studies on hydrogenation of olefins in multiphase fixed bed reactors

    Energy Technology Data Exchange (ETDEWEB)

    Battsengel, B.; Datsevitch, L.; Jess, A. [Bayreuth Univ. (Germany). Dept. of Chemical Engineering

    2003-07-01

    Multi phase reactors like trickle bed systems are frequently used for gas-liquid reactions. In general, they have complex mass and heat transfer characteristics; scale-up is therefore difficult. The present work focuses on the role of mass transfer on the effective reaction rate, taking catalytic octene hydrogenation as a model reaction. The reaction rate in a trickle bed reactor is by a factor of about 20 smaller than (theoretically) in the absence of any mass transfer limitations. Based on the experimental results, the so-called pre-saturation concept is presented, where only the liquid saturated with hydrogen is fed into the reactor. The effective reaction rate in this two phase system (liquid and solid cat.) is equal or even higher than in a trickle bed reactor. Scale-up problems do not occur, and the pre-saturation concept has also other advantages (lower energy consumption), as discussed in detail in this paper. (orig.)

  9. Observations on the life history of giant water bugs Lethocerus Mayr, 1853 (Heteroptera: Nepomorpha: Belostomatidae in the Gangetic plains of India and Nepal

    Directory of Open Access Journals (Sweden)

    H. Nesemann

    2013-06-01

    Full Text Available Two species of giant water bugs Lethocerus were found in the Gangetic plains of northern India and Nepal. Lethocerus indicus is widespread, whereas a single record of Lethocerus patruelis confirms the eastern distribution range in Bihar. Four instars of aquatic nymphs occur exclusively in temporary shallow stagnant water bodies which harbor rich amphibian populations but lack permanent fish fauna. From mid-August to the first week of November adults fly. Later they live submerged in aquatic habitats of large rivers and permanent stagnant water bodies which harbor diverse fish fauna. Repeated findings of adults with ventrally attached egg-shaped pupae of aquatic mites (Hydracarina suggest that these are host-specific ones of Lethocerus. Thus, the occurrence of protelean parasites on giant water bugs in the Gangetic plains is a previously unknown unique finding since apparently mites have been noticed only from other Nepomorpha families.

  10. Fluidized bed combustion: mixing and pollutant limitation

    Energy Technology Data Exchange (ETDEWEB)

    Leckner, B. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Energy Conversion

    1997-10-01

    Fluidized bed combustion (FBC) has been applied commercially during a few decades, and sufficient knowledge is gained to design boilers with sizes of up to several hundreds of megawatt thermal power (MW{sub th}). The knowledge of what goes on inside a large combustion chamber is still limited, however, and this impedes further optimization and efficient solution of problems that might occur. Despite this lack of knowledge the present survey deals with combustion chamber processes and discusses mixing and distribution of fuel and air in the combustion chamber and its importance for sulphur capture and reduction of emissions of nitrogen oxides. It is desirable to present the material in a general way and to cover the entire field of FBC. However, the scarce openly published information deals mostly with coal combustion in atmospheric circulating fluidized bed (CFB) combustors, and therefore this application will receive most attention, but reference is also made to pressurized combustion and to other fuels than coal. In this context the important work made in the LIEKKI project on the analysis of different fuels and on the influence of pressure should be especially pointed out. (orig.)

  11. Equilibrium modeling of gasification: Gibbs free energy minimization approach and its application to spouted bed and spout-fluid bed gasifiers

    International Nuclear Information System (INIS)

    Jarungthammachote, S.; Dutta, A.

    2008-01-01

    Spouted beds have been found in many applications, one of which is gasification. In this paper, the gasification processes of conventional and modified spouted bed gasifiers were considered. The conventional spouted bed is a central jet spouted bed, while the modified spouted beds are circular split spouted bed and spout-fluid bed. The Gibbs free energy minimization method was used to predict the composition of the producer gas. The major six components, CO, CO 2 , CH 4 , H 2 O, H 2 and N 2 , were determined in the mixture of the producer gas. The results showed that the carbon conversion in the gasification process plays an important role in the model. A modified model was developed by considering the carbon conversion in the constraint equations and in the energy balance calculation. The results from the modified model showed improvements. The higher heating values (HHV) were also calculated and compared with the ones from experiments. The agreements of the calculated and experimental values of HHV, especially in the case of the circular split spouted bed and the spout-fluid bed were observed

  12. Adult Bed-Wetting: A Concern?

    Science.gov (United States)

    Adult bed-wetting: A concern? My 24-year-old husband has started to wet the bed at ... of Privacy Practices Notice of Nondiscrimination Manage Cookies Advertising Mayo Clinic is a not-for-profit organization ...

  13. Control of the Bed Temperature of a Circulating Fluidized Bed Boiler by using Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    AYGUN, H.

    2012-05-01

    Full Text Available Circulating fluidized bed boilers are increasingly used in the power generation due to their higher combustion efficiency and lower pollutant emissions. Such boilers require an effective control of the bed temperature, because it influences the boiler combustion efficiency and the rate of harmful emissions. A Particle-Swarm-Optimization-Proportional-Integrative-Derivative (PSO-PID controller for the bed temperature of a circulating fluidized bed boiler is presented. In order to prove the capability of the proposed controller, its performances are compared at different boiler loads with those of a Fuzzy Logic (FL controller. The simulation results demonstrate some advantages of the proposed controller.

  14. Study on transient of fluidized bed nuclear reactor

    International Nuclear Information System (INIS)

    Streck, E.E.

    1988-01-01

    The point kinetic equations for a Fluidized-Bed Nuclear Reactor are solved by the method of Hansen. Due to the time varying nature of the reactor volume, the equations have a non-conventional formulation (moving boundary problem), but the method of solution preserves its asymptotic convergence and efficiency characteristics under this formulation. A one dimensional and linearized thermal hydraulics feedback model was coupled to the point kinetic equations in order to obtain a more realistic representation of the reactor power. The resulting equations are solved by the Euler explicit method. (author)

  15. Supported Photocatalyst for Removal of Emerging Contaminants from Wastewater in a Continuous Packed-Bed Photoreactor Configuration

    Directory of Open Access Journals (Sweden)

    Mª Emma Borges

    2015-02-01

    Full Text Available Water pollution from emerging contaminants (ECs or emerging pollutants is an important environmental problem. Heterogeneous photocatalytic treatment, as advanced oxidation treatment of wastewater effluents, has been proposed to solve this problem. In this paper, a heterogeneous photocatalytic process was studied for emergent contaminants removal using paracetamol as a model contaminant molecule. TiO2 photocatalytic activity was evaluated using two photocatalytic reactor configurations: Photocatalyst solid suspension in wastewater in a stirred photoreactor and TiO2 supported on glass spheres (TGS configuring a packed bed photoreactor. The surface morphology and texture of the TGS were monitored by scanning electron microscope (SEM. The influence of photocatalyst amount and wastewater pH were evaluated in the stirred photoreactor and the influence of wastewater flowrate was tested in the packed bed photoreactor, in order to obtain the optimal operation conditions. Moreover, results obtained were compared with those obtained from photolysis and adsorption studies, using the optimal operation conditions. Good photocatalytic activities have been observed and leads to the conclusion that the heterogeneous photocatalytic system in a packed bed is an effective method for removal of emerging pollutants.

  16. Fluidization quality analyzer for fluidized beds

    Science.gov (United States)

    Daw, C.S.; Hawk, J.A.

    1995-07-25

    A control loop and fluidization quality analyzer for a fluidized bed utilizes time varying pressure drop measurements. A fast-response pressure transducer measures the overall bed pressure drop, or over some segment of the bed, and the pressure drop signal is processed to produce an output voltage which changes with the degree of fluidization turbulence. 9 figs.

  17. How to Find a Bug in Ten Thousand Lines Transport Solver? Outline of Experiences from AN Advection-Diffusion Code Verification

    Science.gov (United States)

    Zamani, K.; Bombardelli, F.

    2011-12-01

    Almost all natural phenomena on Earth are highly nonlinear. Even simplifications to the equations describing nature usually end up being nonlinear partial differential equations. Transport (ADR) equation is a pivotal equation in atmospheric sciences and water quality. This nonlinear equation needs to be solved numerically for practical purposes so academicians and engineers thoroughly rely on the assistance of numerical codes. Thus, numerical codes require verification before they are utilized for multiple applications in science and engineering. Model verification is a mathematical procedure whereby a numerical code is checked to assure the governing equation is properly solved as it is described in the design document. CFD verification is not a straightforward and well-defined course. Only a complete test suite can uncover all the limitations and bugs. Results are needed to be assessed to make a distinction between bug-induced-defect and innate limitation of a numerical scheme. As Roache (2009) said, numerical verification is a state-of-the-art procedure. Sometimes novel tricks work out. This study conveys the synopsis of the experiences we gained during a comprehensive verification process which was done for a transport solver. A test suite was designed including unit tests and algorithmic tests. Tests were layered in complexity in several dimensions from simple to complex. Acceptance criteria defined for the desirable capabilities of the transport code such as order of accuracy, mass conservation, handling stiff source term, spurious oscillation, and initial shape preservation. At the begining, mesh convergence study which is the main craft of the verification is performed. To that end, analytical solution of ADR equation gathered. Also a new solution was derived. In the more general cases, lack of analytical solution could be overcome through Richardson Extrapolation and Manufactured Solution. Then, two bugs which were concealed during the mesh convergence

  18. Characteristics of Sawdust and Cocopeat Beddings, and Their Usefulness According to the Fan and Pen Location for Rearing Hanwoo Cattle.

    Science.gov (United States)

    Ahn, Gyu Chul; Jang, Sun Sik; Lee, Kang Yeon; Kwak, Wan Sup; Oh, Young Kyun; Park, Keun Kyu

    2016-03-01

    This study was designed to examine the characteristics of sawdust and cocopeat bedding materials, including physicochemical properties (Exp. I) and on-farm trial (Exp. II). In Exp. I, the proportion of particle size was in the order of sawdust> cocopeat India>cocopeat Vietnam (pcocopeat Vietnam>sawdust (pfan (blowing 2.00 m/s) and no fan treatments, and feed bunk side (FB) and water supply side (WS) within a pen (4.5 m, width×9.0 m, length). Beddings were replaced with fresh bedding materials when moisture concentrations were over 65%. No interactions among treatments were detected for moisture concentration and increment rates, and ammonia concentrations, but a significant effect was observed (pfan than with fan. Moisture concentrations and increment rate within a pen were also higher (pfan-FB and sawdust-fan-FB were replaced with fresh bedding material between 4 to 5 experimental weeks. The ammonia concentrations and pH of beddings were not significantly different among treatments. Therefore, using cocopeat bedding with a blowing fan can extend twice the bedding utilization period, and WS within a pen showed twice the bedding-life compared to FB. Despite the outstanding characteristics of cocopeat compared with sawdust, using cocopeat as an alternative for sawdust bedding is not recommended for cattle management, considering it has 4.4 times higher bedding cost and a dust production problem.

  19. A safety re-evaluation of the AVR pebble bed reactor operation and its consequences for future HTR concepts

    Energy Technology Data Exchange (ETDEWEB)

    Moormann, R.

    2008-06-15

    The AVR pebble bed reactor (46 MW{sub th}) was operated 1967-88 at coolant outlet temperatures up to 990 C. A principle difference of pebble bed HTRs as AVR to conventional reactors is the continuous movement of fuel element pebbles through the core which complicates thermohydraulic, nuclear and safety estimations. Also because of a lack of other experience AVR operation is still a relevant basis for future pebble bed HTRs and thus requires careful examination. This paper deals mainly with some insufficiently published unresolved safety problems of AVR operation and of pebble bed HTRs but skips the widely known advantageous features of pebble bed HTRs. The AVR primary circuit is heavily contaminated with metallic fission products (Sr-90, Cs-137) which create problems in current dismantling. The amount of this contamination is not exactly known, but the evaluation of fission product deposition experiments indicates that the end of life contamination reached several percent of a single core inventory, which is some orders of magnitude more than precalculated and far more than in large LWRs. A major fraction of this contamination is bound on graphitic dust and thus partly mobile in depressurization accidents, which has to be considered in safety analyses of future reactors. A re-evaluation of the AVR contamination is performed here in order to quantify consequences for future HTRs (400 MW{sub th}). It leads to the conclusion that the AVR contamination was mainly caused by inadmissible high core temperatures, increasing fission product release rates, and not - as presumed in the past - by inadequate fuel quality only. The high AVR core temperatures were detected not earlier than one year before final AVR shut-down, because a pebble bed core cannot yet be equipped with instruments. The maximum core temperatures are still unknown but were more than 200 K higher than calculated. Further, azimuthal temperature differences at the active core margin of up to 200 K were

  20. A safety re-evaluation of the AVR pebble bed reactor operation and its consequences for future HTR concepts

    International Nuclear Information System (INIS)

    Moormann, R.

    2008-06-01

    The AVR pebble bed reactor (46 MW th ) was operated 1967-88 at coolant outlet temperatures up to 990 C. A principle difference of pebble bed HTRs as AVR to conventional reactors is the continuous movement of fuel element pebbles through the core which complicates thermohydraulic, nuclear and safety estimations. Also because of a lack of other experience AVR operation is still a relevant basis for future pebble bed HTRs and thus requires careful examination. This paper deals mainly with some insufficiently published unresolved safety problems of AVR operation and of pebble bed HTRs but skips the widely known advantageous features of pebble bed HTRs. The AVR primary circuit is heavily contaminated with metallic fission products (Sr-90, Cs-137) which create problems in current dismantling. The amount of this contamination is not exactly known, but the evaluation of fission product deposition experiments indicates that the end of life contamination reached several percent of a single core inventory, which is some orders of magnitude more than precalculated and far more than in large LWRs. A major fraction of this contamination is bound on graphitic dust and thus partly mobile in depressurization accidents, which has to be considered in safety analyses of future reactors. A re-evaluation of the AVR contamination is performed here in order to quantify consequences for future HTRs (400 MW th ). It leads to the conclusion that the AVR contamination was mainly caused by inadmissible high core temperatures, increasing fission product release rates, and not - as presumed in the past - by inadequate fuel quality only. The high AVR core temperatures were detected not earlier than one year before final AVR shut-down, because a pebble bed core cannot yet be equipped with instruments. The maximum core temperatures are still unknown but were more than 200 K higher than calculated. Further, azimuthal temperature differences at the active core margin of up to 200 K were observed