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Sample records for execute severe phytotoxicity

  1. Phragmites australis root secreted phytotoxin undergoes photo-degradation to execute severe phytotoxicity.

    Science.gov (United States)

    Rudrappa, Thimmaraju; Choi, Yong Seok; Levia, Delphis F; Legates, David R; Lee, Kelvin H; Bais, Harsh P

    2009-06-01

    Our study organism, Phragmites australis (common reed), is a unique invader in that both native and introduced lineages are found coexisting in North America. This allows one to make direct assessments of physiological differences between these different subspecies and examine how this relates to invasiveness. Recent efforts to understand plant invasive behavior show that some invasive plants secrete a phytotoxin to ward-off encroachment by neighboring plants (allelopathy) and thus provide the invaders with a competitive edge in a given habitat. Here we show that a varying climatic factor like ultraviolet (UV) light leads to photo-degradation of secreted phytotoxin (gallic acid) in P. australis rhizosphere inducing higher mortality of susceptible seedlings. The photo-degraded product of gallic acid (hereafter GA), identified as mesoxalic acid (hereafter MOA), triggered a similar cell death cascade in susceptible seedlings as observed previously with GA. Further, we detected the biological concentrations of MOA in the natural stands of exotic and native P. australis. Our studies also show that the UV degradation of GA is facilitated at an alkaline pH, suggesting that the natural habitat of P. australis may facilitate the photo-degradation of GA. The study highlights the persistence of the photo-degraded phytotoxin in the P. australis's rhizosphere and its inhibitory effects against the native plants.

  2. Effects of alcoholism severity and smoking on executive neurocognitive function.

    Science.gov (United States)

    Glass, Jennifer M; Buu, Anne; Adams, Kenneth M; Nigg, Joel T; Puttler, Leon I; Jester, Jennifer M; Zucker, Robert A

    2009-01-01

    Neurocognitive deficits in chronic alcoholic men are well documented. Impairments include memory, visual-spatial processing, problem solving and executive function. The cause of impairment could include direct effects of alcohol toxicity, pre-existing cognitive deficits that predispose towards substance abuse, comorbid psychiatric disorders and abuse of substances other than alcohol. Cigarette smoking occurs at higher rates in alcoholism and has been linked to poor cognitive performance, yet the effects of smoking on cognitive function in alcoholism are often ignored. We examined whether chronic alcoholism and chronic smoking have effects on executive function. Alcoholism and smoking were examined in a community-recruited sample of alcoholic and non-alcoholic men (n = 240) using standard neuropsychological and reaction-time measures of executive function. Alcoholism was measured as the average level of alcoholism diagnoses across the study duration (12 years). Smoking was measured in pack-years. Both alcoholism and smoking were correlated negatively with a composite executive function score. For component measures, alcoholism was correlated negatively with a broad range of measures, whereas smoking was correlated negatively with measures that emphasize response speed. In regression analyses, both smoking and alcoholism were significant predictors of executive function composite. However, when IQ is included in the regression analyses, alcoholism severity is no longer significant. Both smoking and alcoholism were related to executive function. However, the effect of alcoholism was not independent of IQ, suggesting a generalized effect, perhaps affecting a wide range of cognitive abilities of which executive function is a component. On the other hand, the effect of smoking on measures relying on response speed were independent of IQ, suggesting a more specific processing speed deficit associated with chronic smoking.

  3. Executive dysfunction, severity of traumatic brain injury, and IQ in workers with disabilities.

    Science.gov (United States)

    Matheson, Leonard

    2010-01-01

    To study whether severity of traumatic brain injury and the intelligence quotient are related to executive dysfunction. Sixty-two adults with brain injury who were referred for a work capacity evaluation. Retrospective review of severity of traumatic brain injury, intelligence quotient from a previously-conducted neuropsychological evaluation, determination of executive function status from the neuropsychological evaluation, and both self-report and informant-report executive dysfunction scores from the Behavior Rating Inventory of Executive Function. Executive dysfunction and the intelligence quotient are related to severity of traumatic brain injury, but executive dysfunction and the intelligence quotient are not related to each other. Executive dysfunction as determined by a neuropsychological evaluation was not consistent with clients' self-reports but was consistent with informant-reported executive dysfunction. Five types of executive dysfunction were reported by knowledgeable informants, with significant elevations on the Shift, Plan/Organize, Task Monitor, Organization of Materials, and Working Memory BRIEF clinical scales. The intelligence quotient is not a useful indicator of executive dysfunction. Informant-report executive dysfunction is a reliable and potentially useful adjunct to a neuropsychological evaluation. Working memory is the most severe type of executive dysfunction and may not be adequately measured by current neuropsychological evaluation methods.

  4. Catechin secretion and phytotoxicity

    Science.gov (United States)

    Kaushik, Shail

    2010-01-01

    Research indicates that the invasiveness of Centaurea stoebe is attributed to the stronger allelopathic effects on the native North American species than on the related European species, which is one of the unquestionable aspects of the “novel weapons hypothesis (NWH).” Studies originating from controlled to field conditions have shown that C. stoebe utilizes its biochemical potential to exert its invasiveness. The roots of C. stoebe secrete a potent phytotoxin, catechin, which has a detrimental effect on the surrounding plant species. Although, studies on catechin secretion and phytotoxicity represent one of the most well studied systems describing negative plant-plant interactions, it has also sparked controversies lately due to its phytotoxicity dosages and secretion effluxes. Previous reports negate the phytotoxic and pro-oxidant nature of catechin.1–3 In our recent study we have shown that catechin is highly phytotoxic against Arabidopsis thaliana and Festuca idahoensis. We also show that (±) catechin applied to roots of A. thaliana induces reactive oxygen species (ROS) confirming the pro-oxidant nature of catechin. In addition, activation of signature cell death genes such as acd2 and cad1 post catechin treatment in A. thaliana ascertains the phytotoxic nature of catechin. PMID:21057643

  5. Oculomotor executive function abnormalities with increased tic severity in Tourette syndrome.

    Science.gov (United States)

    Jeter, Cameron B; Patel, Saumil S; Morris, Jeffrey S; Chuang, Alice Z; Butler, Ian J; Sereno, Anne B

    2015-02-01

    Reports conflict as to whether Tourette syndrome (TS) confers deficits in executive function. This study's aim was to evaluate executive function in youths with TS using oculomotor tasks while controlling for confounds of tic severity, age, medication, and severity of comorbid disorders. Four saccade tasks requiring the executive functions of response generation, response inhibition, and working memory (prosaccade, antisaccade, 0-back, and 1-back) were administered. Twenty youths with TS and low tic severity (TS-low), nineteen with TS and moderate tic severity (TS-moderate), and 29 typically developing control subjects (Controls) completed the oculomotor tasks. There were small differences across groups in the prosaccade task. Controlling for any small sensorimotor differences, TS-moderate subjects had significantly higher error rates than Controls and TS-low subjects in the 0-back and 1-back tasks. In the 1-back task, these patients also took longer to respond than Controls or TS-low subjects. In a highly controlled design, the findings demonstrate for the first time that increased tic severity in TS is associated with impaired response inhibition and impaired working memory and that these executive function deficits cannot be accounted for by differences in age, medication or comorbid symptom severity. © 2014 Association for Child and Adolescent Mental Health.

  6. Investigating executive functions in children with severe speech and movement disorders using structured tasks

    Directory of Open Access Journals (Sweden)

    Kristine eStadskleiv

    2014-09-01

    Full Text Available Executive functions are the basis for goal-directed activity and include planning, monitoring, and inhibition, and language seems to play a role in the development of these functions. There is a tradition of studying executive function in both typical and atypical populations, and the present study investigates executive functions in children with severe speech and motor impairments who are communicating using communication aids with graphic symbols, letters and/or words. There are few neuropsychological studies of children in this group and little is known about their cognitive functioning, including executive functions. It was hypothesized that aided communication would tax executive functions more than speech. 29 children using communication aids and 27 naturally speaking children participated. Structured tasks resembling everyday activities, where the action goals had to be reached through communication with a partner, were used to get information about executive functions. The children a directed the partner to perform actions like building a Lego tower from a model the partner could not see and b gave information about an object without naming it to a person who had to guess what object it was. The executive functions of planning, monitoring and impulse control were coded from the children’s on-task behavior. Both groups solved most of the tasks correctly, indicating that aided communicators are able to use language to direct another person to do a complex set of actions. Planning and lack of impulsivity was positively related to task success in both groups. The aided group completed significantly fewer tasks, spent longer time and showed more variation in performance than the comparison group. The aided communicators scored lower on planning and showed more impulsivity than the comparison group, while both groups showed an equal degree of monitoring of the work progress. The results are consistent with the hypothesis that aided language

  7. Investigating executive functions in children with severe speech and movement disorders using structured tasks.

    Science.gov (United States)

    Stadskleiv, Kristine; von Tetzchner, Stephen; Batorowicz, Beata; van Balkom, Hans; Dahlgren-Sandberg, Annika; Renner, Gregor

    2014-01-01

    Executive functions are the basis for goal-directed activity and include planning, monitoring, and inhibition, and language seems to play a role in the development of these functions. There is a tradition of studying executive function in both typical and atypical populations, and the present study investigates executive functions in children with severe speech and motor impairments who are communicating using communication aids with graphic symbols, letters, and/or words. There are few neuropsychological studies of children in this group and little is known about their cognitive functioning, including executive functions. It was hypothesized that aided communication would tax executive functions more than speech. Twenty-nine children using communication aids and 27 naturally speaking children participated. Structured tasks resembling everyday activities, where the action goals had to be reached through communication with a partner, were used to get information about executive functions. The children (a) directed the partner to perform actions like building a Lego tower from a model the partner could not see and (b) gave information about an object without naming it to a person who had to guess what object it was. The executive functions of planning, monitoring, and impulse control were coded from the children's on-task behavior. Both groups solved most of the tasks correctly, indicating that aided communicators are able to use language to direct another person to do a complex set of actions. Planning and lack of impulsivity was positively related to task success in both groups. The aided group completed significantly fewer tasks, spent longer time and showed more variation in performance than the comparison group. The aided communicators scored lower on planning and showed more impulsivity than the comparison group, while both groups showed an equal degree of monitoring of the work progress. The results are consistent with the hypothesis that aided language tax

  8. Poor Executive Functions among Children with Moderate-into-Severe Asthma: Evidence from WCST Performance.

    Science.gov (United States)

    Taha, Haitham

    2017-01-01

    Executive functions (EFs) measures of 27 asthmatic children, with general learning difficulties, were tested by using the Wisconsin card sorting test (WCST), and were compared to the performances of 30 non-asthmatic children with general learning difficulties. The results revealed that the asthmatic group has poor performance through all the WCST psychometric parameters and especially the perseverative errors one. The results were discussed in light of the postulation that poor EFs could be associated with the learning difficulties of asthmatic children. Neurophysiological framework has been suggested to explain the etiology of poor EFs among children with moderate into severe asthma.

  9. Attitudes of Fortune 500 corporate executives toward the employability of persons with severe disabilities: a national study.

    Science.gov (United States)

    Levy, J M; Jessop, D J; Rimmerman, A; Levy, P H

    1992-04-01

    Executives (N = 341) responsible for hiring decisions in Fortune 500 industrial and service corporations returned a mail questionnaire measuring their attitudes toward persons with severe disabilities and their employability. Responses indicated that attitudes were favorable to persons with disabilities and to their employability, both in terms of advantages for the individual and lack of disadvantages for others in the work setting. Significant differences in attitudes existed among subgroups of executives. Executives who had contact with persons with disabilities in the corporate work world had more positive attitudes than did executives who did not have such experiences.

  10. The Phytotoxicity of Designated Pollutants

    Science.gov (United States)

    1982-11-01

    lengths. Results paralleled emer- gence; a reduction of growth occurred when fuel was applied (Table 46). Shoots appeared equally stressed since root...1954, Mode of action of phytotoxic oils, Weeds 3:55-65. Williams, G. R., E. Cumins , A. C. Gardner, M. Palmier, and T. Rubidge, 1981, The growth of

  11. Investigating executive functions in children with severe speech and movement disorders using structured tasks

    NARCIS (Netherlands)

    Stadskleiv, K.; Tetzchner, S. von; Batorowicz, B.; Balkom, L.J.M. van; Dahlgren-Sandberg, A.; Renner, G.

    2014-01-01

    Executive functions are the basis for goal-directed activity and include planning, monitoring, and inhibition, and language seems to play a role in the development of these functions. There is a tradition of studying executive function in both typical and atypical populations, and the present study

  12. Cytotoxicity and phytotoxicity of trichothecene mycotoxins produced by Fusarium spp.

    Science.gov (United States)

    Abbas, Hamed K; Yoshizawa, Takumi; Shier, W Thomas

    2013-11-01

    Trichothecenes, a major class of mycotoxins produced by Fusarium, Myrothecium, and Stachybotrys species, are toxic to both plants and mammals. Simple trichothecenes, including type A (e.g., T-2 toxin) and type B (e.g., deoxynivalenol), are generally less toxic than macrocyclic trichothecenes. We sought to determine if simple trichothecenes are a potential source of candidates for development as bioherbicides, which require high phytotoxicity and low mammalian toxicity. We examined 28 simple trichothecenes in vitro for phytotoxicity using a small aquatic plant, Lemna pausicostata, and for mammalian toxicity using four cultured mammalian cell lines. Several structure-activity relationships were identified, including the following two, which may be relevant to bioherbicide development: peracetylation of type B trichothecenes and de-epoxidation of type A trichothecenes both substantially reduced mammalian toxicity with little effect on phytotoxicity. It was concluded that simple trichothecenes possessing strong phytotoxicity and minimal mammalian toxicity in vitro can be identified. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. [Formula: see text]Executive functions and social information processing in adolescents with severe behavior problems.

    Science.gov (United States)

    Van Nieuwenhuijzen, M; Van Rest, M M; Embregts, P J C M; Vriens, A; Oostermeijer, S; Van Bokhoven, I; Matthys, W

    2017-02-01

    One tradition in research for explaining aggression and antisocial behavior has focused on social information processing (SIP). Aggression and antisocial behavior have also been studied from the perspective of executive functions (EFs), the higher-order cognitive abilities that affect other cognitive processes, such as social cognitive processes. The main goal of the present study is to provide insight into the relation between EFs and SIP in adolescents with severe behavior problems. Because of the hierarchical relation between EFs and SIP, we examined EFs as predictors of SIP. We hypothesized that, first, focused attention predicts encoding and interpretation, second, inhibition predicts interpretation, response generation, evaluation, and selection, and third, working memory predicts response generation and selection. The participants consisted of 94 respondents living in residential facilities aged 12-20 years, all showing behavior problems in the clinical range according to care staff. EFs were assessed using subtests from the Amsterdam Neuropsychological Test battery. Focused attention was measured by the Flanker task, inhibition by the GoNoGo task, and working memory by the Visual Spatial Sequencing task. SIP was measured by video vignettes and a structured interview. The results indicate that positive evaluation of aggressive responses is predicted by impaired inhibition and selection of aggressive responses by a combination of impaired focused attention and inhibition. It is concluded that different components of EFs as higher-order cognitive abilities affect SIP.

  14. Isolation of a phytotoxic isocoumarin from Diaporthe eres-infected Hedera helix (English ivy) and synthesis of its phytotoxic analogs.

    Science.gov (United States)

    Meepagala, Kumudini M; Briscoe, William E; Techen, Natascha; Johnson, Robert D; Clausen, Brandon M; Duke, Stephen O

    2018-01-01

    The fungus Diaporthe eres was isolated from a fungal pathogen-infected leaf of Hedera helix (English ivy) exhibiting necrosis. It is hypothesized that the causative fungus produces phytotoxins as evidenced by necrotic lesions on the leaves. The fungus was isolated and grown in Czapek Dox broth culture medium and potato dextrose broth culture medium and identified as Diaporthe eres. The ethyl acetate extracts of the culture broths were phytotoxic to lettuce (Lactuca sativa) and bentgrass (Agrostis stolonifera). 3,4-Dihydro-8-hydroxy-3,5-dimethylisocoumarin (1) and tyrosol (2) were isolated and identified as the phytotoxic constituents. Six analogs of 3,4-dihydro-isocoumarin were synthesized and shown to be phytotoxic. The synthesized 3,4-dihydro-8-hydroxy-3,7-dimethylisocoumarin and 3,4-dihydro-8-hydroxy-3,3,7-trimethylisocoumarin were two- to three-fold more phytotoxic than the naturally occurring 1 in a Lemna paucicostata growth bioassay. Synthesis and herbicidal activities of the several new analogs of 1 are reported for the first time. These promising molecules should be used as templates for synthesis and testing of more analogs. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  15. Phytotoxic property of the invasive plant Tithonia diversifolia and a phytotoxic substance.

    Science.gov (United States)

    Suzuki, Masahiko; Iwasaki, Arihiro; Suenaga, Kiyotake; Kato-Noguchi, Hisashi

    2017-06-01

    Tithonia diversifolia (Hermsl.) A. Gray is a perennial invasive plant and spreads quickly in the invasive areas. The extracts of T. diversifolia were found to be toxic to several crop plant species such as rice, maize, sorghum, lettuce and cowpea, and several putative allelopathic substances were identified. However, there is limited information available for the effects of T. diversifolia on wild plants including weed plant species. We investigated the allelopathic potential of T. diversifolia extracts on weed plants, and searched for phytotoxic substances with allelopathic activity. An aqueous methanol extract of T. diversifolia leaves inhibited the growth of weed plants, Lolium multiflorum Lam., Phleum pretense L., Echinochloa crus-galli (L.) Beauv. The extract was then purified by several chromatographic runs and a phytotoxic substance with allelopathic activity was isolated and identified by spectral analysis as tagitinin C. The substance inhibited the growth of Lolium multiflorum, Phleum pratense and Echinochloa crus-galli at concentrations greater than 0.1 - 0.3 mM. The present results suggest that T. diversifolia may possess allelopathic potential on weed plants and tagitinin C may be responsible for the allelopathic effects of T. diversifolia. The allelopathic potential of T. diversifolia may contribute to its invasive characteristics.

  16. The relationship of theory of mind and executive functions to symptom type and severity in children with autism.

    Science.gov (United States)

    Joseph, Robert M; Tager-Flusberg, Helen

    2004-01-01

    Although neurocognitive impairments in theory of mind and in executive functions have both been hypothesized to play a causal role in autism, there has been little research investigating the explanatory power of these impairments with regard to autistic symptomatology. The present study examined the degree to which individual differences in theory of mind and executive functions could explain variations in the severity of autism symptoms. Participants included 31 verbal, school-aged children with autism who were administered a battery of tests assessing the understanding of mental states (knowledge and false belief) and executive control skills (working memory, combined working memory and inhibitory control, and planning) and who were behaviorally evaluated for autism severity in the three core symptom domains. Whereas theory of mind and executive control abilities explained the significant variance beyond that accounted for by language level in communication symptoms, neither explained the significant variance in reciprocal social interaction or repetitive behaviors symptoms. These findings are discussed in terms of a proposed distinction between higher level, cognitive-linguistic aspects of theory of mind and related executive control skills, and more fundamental social-perceptual processes involved in the apprehension of mental state information conveyed through eyes, faces, and voices, which may be more closely linked to autistic deficits in social reciprocity.

  17. Screening agrochemicals as potential protectants of plants against ozone phytotoxicity

    International Nuclear Information System (INIS)

    Saitanis, Costas J.; Lekkas, Dimitrios V.; Agathokleous, Evgenios; Flouri, Fotini

    2015-01-01

    We tested seven contemporary agrochemicals as potential plant protectants against ozone phytotoxicity. In nine experiments, Bel-W3 tobacco plants were experienced weekly exposures to a) 80 nmol mol −1 of ozone-enriched or ozone-free air in controlled environment chambers, b) an urban air polluted area, and c) an agricultural-remote area. Ozone caused severe leaf injury, reduced chlorophylls' and total carotenoids' content, and negatively affected photosynthesis and stomatal conductance. Penconazole, (35% ± 8) hexaconazole (28% ± 5) and kresoxim-methyl (28% ± 15) showed higher plants’ protection (expressed as percentage; mean ± s.e.) against ozone, although the latter exhibited a high variability. Azoxystrobin (21% ± 15) showed lower protection efficacy and Benomyl (15% ± 9) even lower. Trifloxystrobin (7% ± 11) did not protect the plants at all. Acibenzolar-S-methyl + metalaxyl-M (Bion MX) (−6% ± 17) exhibited the higher variability and contrasting results: in some experiments it showed some protection while in others it intensified the ozone injury by causing phytotoxic symptoms on leaves, even in control plants. - Highlights: • Penconazole and hexaconazole offered some protection to plants against ozone. • Bion MX fungicide caused phytotoxic symptoms to Bel-W3 tobacco plants. • Stomatal conductance was reduced in ozone-fumigated plants. - Seven agrochemicals were assessed as potential protectants against ozone phytotoxicity – triazoles fungicides were the most effective

  18. Prenatal exposure to maternal very severe obesity is associated with impaired neurodevelopment and executive functioning in children.

    Science.gov (United States)

    Mina, Theresia H; Lahti, Marius; Drake, Amanda J; Denison, Fiona C; Räikkönen, Katri; Norman, Jane E; Reynolds, Rebecca M

    2017-07-01

    BackgroundPrenatal maternal obesity has been associated with an increased risk of neurocognitive problems in childhood, but there are fewer studies on executive functioning.MethodsTests and questionnaires to assess neurodevelopment, executive functioning, and the ability to delay gratification were conducted in 113 children (mean (SD)=4.24 (0.63) years of age) born to mothers with very severe obesity (SO, body mass index (BMI)⩾40 kg/m 2 , n=51) or to lean mothers (BMI⩽25 kg/m 2 , n=62).ResultsPrenatal maternal SO predicted poorer neurodevelopment (unstandardized regression coefficient (B)=-0.42, 95% confidence interval (CI) (-0.82; -0.02)), worse problem-solving (odd ratio (OR)=0.60, 95% CI (1.13; 0.07)), and fine motor skills (OR=4.91, 95% CI (1.27; 19.04)), poorer executive functioning in areas of attention, inhibitory control, and working memory (standardized B=3.75, 95% CI (1.01; 13.93)) but not in self-gratification delay. The effects were independent of maternal concurrent psychological well-being and child's BMI, but not independent of maternal education.ConclusionFuture studies should investigate whether perinatal management of maternal obesity could prevent adverse outcomes in child neurodevelopment.

  19. Isolation and identification of a phytotoxic substance from the emergent macrophyte Centrostachys aquatica.

    Science.gov (United States)

    Bich, Tran Thi Ngoc; Kato-Noguchi, Hisashi

    2014-12-01

    Centrostachys aquatica is a perennial emergent macrophyte in marshy places and in rivers. The species was recorded in Senegal and Nigeria, but widespread in tropical Africa, and South and East Asia. Aqueous methanol extracts C. aquatica was found to be toxic to several plant species. However, no phytotoxic substance has been reported in this species. Therefore, we investigated phytotoxic activity and searched for phytotoxic substances with allelopathic activity in C. aquatica. An aqueous methanol extract of C. aquatica inhibited the growth of roots and hypocotyls of cress (Lepidium sativum). The extract was then purified by several chromatographic runs and a phytotoxic substance with allelopathic activity was isolated and identified by spectral analysis as loliolide. Loliolide inhibited cress root and hypocotyl growth at concentrations greater than 0.03 μM. The concentrations required for 50% growth inhibition of cress roots and hypocotyls was 0.18 and 0.15 μM, respectively. These results suggest that loliolide is a phytotoxic substance and may contribute to the allelopathic effect caused by C. aquatica.

  20. Phytotoxic and Nematicidal Components of Lavandula luisieri.

    Science.gov (United States)

    Julio, Luis F; Barrero, Alejandro F; Herrador del Pino, M Mar; Arteaga, Jesús F; Burillo, Jesús; Andres, Maria Fe; Díaz, Carmen E; González-Coloma, Azucena

    2016-02-26

    Several preparations were obtained from the aerial parts of predomesticated Lavandula luisieri, including the essential oil and ethanolic, hexane, and ethyl acetate extractives. Additionally, pilot plant vapor pressure extraction was carried out at a pressure range of 0.5-1.0 bar to give a vapor pressure oil and an aqueous residue. A chemical study of the hexane extract led to the isolation of six necrodane derivatives (1, 2, and 4-7), with four of these (1, 2, 5, and 7) being new, as well as camphor, a cadinane sesquiterpene (9), tormentic acid, and ursolic acid. The EtOAc and EtOH extracts contained a mixture of phenolic compounds with rosmarinic acid being the major component. Workup of the aqueous residue resulted in the isolation of the necrodane 3 and (1R*,2S*,4R*)-p-menth-5-ene-1,2,8-triol (8), both new natural compounds. The structures of the new compounds were established based on their spectroscopic data. The phytotoxic and nematicidal activities of these compounds were evaluated.

  1. Catechin secretion and phytotoxicity: Fact not fiction.

    Science.gov (United States)

    Bais, Harsh P; Kaushik, Shail

    2010-09-01

    Research indicates that the invasiveness of Centaurea stoebe is attributed to the stronger allelopathic effects on the native North American species than on the related European species, which is one of the unquestionable aspects of the "novel weapons hypothesis (NWH)." Studies originating from controlled to field conditions have shown that C. stoebe utilizes its biochemical potential to exert its invasiveness. The roots of C. stoebe secrete a potent phytotoxin, catechin, which has a detrimental effect on the surrounding plant species. Although, studies on catechin secretion and phytotoxicity represent one of the most well studied systems describing negative plant-plant interactions, it has also sparked controversies lately due to its phytotoxicity dosages and secretion effluxes. Previous reports negate the phytotoxic and pro-oxidant nature of catechin.1-3 In our recent study we have shown that catechin is highly phytotoxic against Arabidopsis thaliana and Festuca idahoensis. We also show that (±) catechin applied to roots of A. thaliana induces reactive oxygen species (ROS) confirming the pro-oxidant nature of catechin. In addition, activation of signature cell death genes such as acd2 and cad1 post catechin treatment in A. thaliana ascertains the phytotoxic nature of catechin.

  2. C-Speak Aphasia alternative communication program for people with severe aphasia: importance of executive functioning and semantic knowledge.

    Science.gov (United States)

    Nicholas, Marjorie; Sinotte, Michele P; Helm-Estabrooks, Nancy

    2011-06-01

    Learning how to use a computer-based communication system can be challenging for people with severe aphasia even if the system is not word-based. This study explored cognitive and linguistic factors relative to how they affected individual patients' ability to communicate expressively using C-Speak Aphasia (CSA), an alternative communication computer program that is primarily picture-based. Ten individuals with severe non-fluent aphasia received at least six months of training with CSA. To assess carryover of training, untrained functional communication tasks (i.e., answering autobiographical questions, describing pictures, making telephone calls, describing a short video, and two writing tasks) were repeatedly probed in two conditions: (1) using CSA in addition to natural forms of communication, and (2) using only natural forms of communication, e.g., speaking, writing, gesturing, drawing. Four of the 10 participants communicated more information on selected probe tasks using CSA than they did without the computer. Response to treatment was also examined in relation to baseline measures of non-linguistic executive function skills, pictorial semantic abilities, and auditory comprehension. Only nonlinguistic executive function skills were significantly correlated with treatment response.

  3. C-Speak Aphasia Alternative Communication Program for People with Severe Aphasia: Importance of Executive Functioning and Semantic Knowledge

    Science.gov (United States)

    Nicholas, Marjorie; Sinotte, Michele P.; Helm-Estabrooks, Nancy

    2011-01-01

    Learning how to use a computer-based communication system can be challenging for people with severe aphasia even if the system is not word-based. This study explored cognitive and linguistic factors relative to how they affected individual patients’ ability to communicate expressively using C-Speak Aphasia, (CSA), an alternative communication computer program that is primarily picture-based. Ten individuals with severe non-fluent aphasia received at least six months of training with CSA. To assess carryover of training, untrained functional communication tasks (i.e., answering autobiographical questions, describing pictures, making telephone calls, describing a short video, and two writing tasks) were repeatedly probed in two conditions: 1) using CSA in addition to natural forms of communication, and 2) using only natural forms of communication, e.g., speaking, writing, gesturing, drawing. Four of the ten participants communicated more information on selected probe tasks using CSA than they did without the computer. Response to treatment also was examined in relation to baseline measures of non-linguistic executive function skills, pictorial semantic abilities, and auditory comprehension. Only nonlinguistic executive function skills were significantly correlated with treatment response. PMID:21506045

  4. Phytotoxic activity of flavonoids from Dicranostyles ampla.

    Science.gov (United States)

    Castro, Amaya; Cantrell, Charles L; Hale, Amber L; Duke, Stephen O

    2010-08-01

    Crude extracts from over 16 species of plants from the family Convolvulaceae were evaluated for phytotoxic activity against Agrostis stolonifera (bentgrass) and Lactuca sativa (lettuce) at 1000 microg/mL. Ethanol extracts of Dicranostyles ampla Ducke were among the most active of those species tested. Systematic bioassay-guided fractionation of the ethanol extract of the aerial parts from this species was performed to identify specifically the phytotoxic compounds. Two phytotoxic flavonoids, dihydromyricetin (1) and myricetin-3-O-alpha-rhamnoside or myricetrin (2), were found to be responsible for much of the activity of the extract as a whole in the A. stolonifera and L. sativa bioassay. In a Lemna paucicostata bioassay, 1 and 2 had no activity at 100 microM.

  5. Cytotoxic and phytotoxic actions of Heliotropium strigosum.

    Science.gov (United States)

    Shah, Syed Majid; Hussain, Sajid; Khan, Arif-Ullah; Shah, Azhar-Ul-Haq Ali; Khan, Haroon; Ullah, Farhat; Barkatullah

    2015-05-01

    This study describes the cytotoxic and phytotoxic activities of the crude extract of Heliotropium strigosum and its resultant fractions. In brine shrimp toxicology assays, profound cytotoxicity was displayed by ethyl acetate (LD50 8.3 μg/ml) and chloroform (LD50 8.8 μg/ml) fractions, followed by relatively weak crude methanolic extract of H. strigosum (LD50 909 μg/ml) and n-hexane fraction (LD50 1000 μg/ml). In case of phytotoxicity activity against Lemna acquinoctialis, highest phytotoxic effect was showed by ethyl acetate fraction (LD50 91.0 μg/ml), while chloroform fraction, plant crude extract and n-hexane, respectively, caused 50%, 30.76 ± 1.1% and 30.7 ± 1.1% inhibitory action at maximum concentration used, that is, 1000 μg/ml. These data indicates that H. strigosum exhibits cytotoxic and phytotoxic potential, which explore its use as anticancer and herbicidal medicine. The ethyl acetate and chloroform fractions were more potent for the evaluated toxicity effects, thus recommended for isolation and identification of the active compounds. © The Author(s) 2012.

  6. Olfactory identification and its relationship to executive functions, memory, and disability one year after severe traumatic brain injury.

    Science.gov (United States)

    Sigurdardottir, Solrun; Andelic, Nada; Skandsen, Toril; Anke, Audny; Roe, Cecilie; Holthe, Oyvor Oistensen; Wehling, Eike

    2016-01-01

    To explore the frequency of posttraumatic olfactory (dys)function 1 year after severe traumatic brain injury (TBI) and determine whether there is a relationship between olfactory identification and neuropsychological test performance, injury severity and TBI-related disability. A population-based multicenter study including 129 individuals with severe TBI (99 males; 16 to 85 years of age) that could accomplish neuropsychological examinations. Olfactory (dys)function (anosmia, hyposmia, normosmia) was assessed by the University of Pennsylvania Smell Identification Test (UPSIT) or the Brief Smell Identification Test (B-SIT). Three tests of the Delis-Kaplan Executive Function System (D-KEFS) were used to assess processing speed, verbal fluency, inhibition and set-shifting, and the California Verbal Learning Test-II was used to examine verbal memory. The Glasgow Outcome Scale-Extended (GOSE) was used to measure disability level. Employing 2 different smell tests in 2 equal-sized subsamples, the UPSIT sample (n = 65) classified 34% with anosmia and 52% with hyposmia, while the B-SIT sample (n = 64) classified 20% with anosmia and 9% with hyposmia. Individuals classified with anosmia by the B-SIT showed significantly lower scores for set-shifting, category switching fluency and delayed verbal memory compared to hyposmia and normosmia groups. Only the B-SIT scores were significantly correlated with neuropsychological performance and GOSE scores. Brain injury severity (Rotterdam CT score) and subarachnoid hemorrhage were related to anosmia. Individuals classified with anosmia demonstrated similar disability as those with hyposmia/normosmia. Different measures of olfaction may yield different estimates of anosmia. Nevertheless, around 1 third of individuals with severe TBI suffered from anosmia, which may also indicate poorer cognitive outcome. (c) 2015 APA, all rights reserved).

  7. Workplace Disruption following Psychological Trauma: Influence of Incident Severity Level on Organizations' Post-Incident Response Planning and Execution.

    Science.gov (United States)

    DeFraia, G S

    2016-04-01

    Psychologically traumatic workplace events (known as critical incidents), which occur globally, are increasing in prevalence within the USA. Assisting employers in their response is a growing practice area for occupational medicine, occupational social work, industrial psychology and other occupational health professions. Traumatic workplace events vary greatly in their level of organizational disruption. To explore whether extent of workplace disruption influences organizations' decisions for post-incident response planning and plan execution. Administrative data mining was employed to examine practice data from a workplace trauma response unit in the USA. Bivariate analyses were conducted to test whether scores from an instrument measuring extent of workplace disruption associated with organizational decisions regarding post-incident response. The more severe and disruptive the incident, the more likely organizations planned for and followed through to deliver on-site interventions. Following more severe incidents, organizations were also more likely to deliver group sessions and to complete follow-up consultations to ensure ongoing worker recovery. Increasing occupational health practitioners' knowledge of varying levels of organizational disruption and familiarity with a range of organizational response strategies improves incident assessment, consultation and planning, and ensures interventions delivered are consistent with the level of assistance needed on both worker and organizational levels.

  8. Workplace Disruption following Psychological Trauma: Influence of Incident Severity Level on Organizations' Post-Incident Response Planning and Execution

    Directory of Open Access Journals (Sweden)

    GS DeFraia

    2016-04-01

    Full Text Available Background: Psychologically traumatic workplace events (known as critical incidents, which occur globally, are increasing in prevalence within the USA. Assisting employers in their response is a growing practice area for occupational medicine, occupational social work, industrial psychology and other occupational health professions. Traumatic workplace events vary greatly in their level of organizational disruption. Objective: To explore whether extent of workplace disruption influences organizations' decisions for post-incident response planning and plan execution. Methods: Administrative data mining was employed to examine practice data from a workplace trauma response unit in the USA. Bivariate analyses were conducted to test whether scores from an instrument measuring extent of workplace disruption associated with organizational decisions regarding post-incident response. Results: The more severe and disruptive the incident, the more likely organizations planned for and followed through to deliver on-site interventions. Following more severe incidents, organizations were also more likely to deliver group sessions and to complete follow-up consultations to ensure ongoing worker recovery. Conclusion: Increasing occupational health practitioners' knowledge of varying levels of organizational disruption and familiarity with a range of organizational response strategies improves incident assessment, consultation and planning, and ensures interventions delivered are consistent with the level of assistance needed on both worker and organizational levels.

  9. Screening agrochemicals as potential protectants of plants against ozone phytotoxicity.

    Science.gov (United States)

    Saitanis, Costas J; Lekkas, Dimitrios V; Agathokleous, Evgenios; Flouri, Fotini

    2015-02-01

    We tested seven contemporary agrochemicals as potential plant protectants against ozone phytotoxicity. In nine experiments, Bel-W3 tobacco plants were experienced weekly exposures to a) 80 nmol mol(-1) of ozone-enriched or ozone-free air in controlled environment chambers, b) an urban air polluted area, and c) an agricultural-remote area. Ozone caused severe leaf injury, reduced chlorophylls' and total carotenoids' content, and negatively affected photosynthesis and stomatal conductance. Penconazole, (35% ± 8) hexaconazole (28% ± 5) and kresoxim-methyl (28% ± 15) showed higher plants' protection (expressed as percentage; mean ± s.e.) against ozone, although the latter exhibited a high variability. Azoxystrobin (21% ± 15) showed lower protection efficacy and Benomyl (15% ± 9) even lower. Trifloxystrobin (7% ± 11) did not protect the plants at all. Acibenzolar-S-methyl + metalaxyl-M (Bion MX) (-6% ± 17) exhibited the higher variability and contrasting results: in some experiments it showed some protection while in others it intensified the ozone injury by causing phytotoxic symptoms on leaves, even in control plants. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Assessing the potential phytotoxicity of digestate from winery wastes.

    Science.gov (United States)

    Da Ros, Cinzia; Libralato, Giovanni; Ghirardini, Annamaria Volpi; Radaelli, Marta; Cavinato, Cristina

    2018-04-15

    In this study, digestate from winery wastes was investigated focusing on phytotoxicity using macrophytes and evaluating the potential contribution of ammonium and copper. Spreading of digestate on soil could represent a suitable approach to recycle nutrients and organic matter, creating an on site circular economy. In this study, digestate quality was evaluated considering both chemical-physical characteristics and biological toxicity applying germination test. The effluent did not meet the entire amendment quality standard defined by Italian law (Decree 75/2010 germination index > 60% with solution of 30% v/v of digestate), but bio-stimulation was observed at low doses (3.15-6.25% v/v) for S. alba and S. saccharatum. The beneficial concentration agreed with Nitrate Directive dose and suggested that limited addition of digestate could have several positive effects on soil characteristics and on crop growth. Specific test using ammonium and copper solutions showed that these pollutants were not directly correlated to observed phytotoxicity. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Describing phytotoxic effects on cumulative germination

    OpenAIRE

    Dias, L.S.

    2001-01-01

    Phytotoxic studies strongly depend on evaluation of germination responses, which implies the need for adequate procedures to account for distinct aspects of the germinative process. For this, indices, comparisons among treatments at various times, and model fitting have been proposed. The objective of this work is to compare the three approaches and select the one providing greater insight and precision. Speed of germination, speed of accumulated germination, the coefficient of the rate of ge...

  12. How preschool executive functioning predicts several aspects of math achievement in Grades 1 and 3: A longitudinal study.

    Science.gov (United States)

    Viterbori, Paola; Usai, M Carmen; Traverso, Laura; De Franchis, Valentina

    2015-12-01

    This longitudinal study analyzes whether selected components of executive function (EF) measured during the preschool period predict several indices of math achievement in primary school. Six EF measures were assessed in a sample of 5-year-old children (N = 175). The math achievement of the same children was then tested in Grades 1 and 3 using both a composite math score and three single indices of written calculation, arithmetical facts, and problem solving. Using previous results obtained from the same sample of children, a confirmatory factor analysis examining the latent EF structure in kindergarten indicated that a two-factor model provided the best fit for the data. In this model, inhibition and working memory (WM)-flexibility were separate dimensions. A full structural equation model was then used to test the hypothesis that math achievement (the composite math score and single math scores) in Grades 1 and 3 could be explained by the two EF components comprising the kindergarten model. The results indicate that the WM-flexibility component measured during the preschool period substantially predicts mathematical achievement, especially in Grade 3. The math composite scores were predicted by the WM-flexibility factor at both grade levels. In Grade 3, both problem solving and arithmetical facts were predicted by the WM-flexibility component. The results empirically support interventions that target EF as an important component of early childhood mathematics education. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Phytotoxicity of chiral herbicide bromacil: Enantioselectivity of photosynthesis in Arabidopsis thaliana

    International Nuclear Information System (INIS)

    Chen, Zunwei; Zou, Yuqin; Wang, Jia; Li, Meichao; Wen, Yuezhong

    2016-01-01

    With the wide application of chiral herbicides and the frequent detection of photosystem II (PSII) herbicides, it is of great importance to assess the direct effects of PSII herbicides on photosynthesis in an enantiomeric level. In the present study, the enantioselective phytotoxicity of bromacil (BRO), typical photosynthesis inhibition herbicide, on Arabidopsis thaliana was investigated. The results showed that S-BRO exhibited a greater inhibition of electron transmission in photosystem I (PSI) of A. thaliana than R-BRO by inhibiting the transcription of fnr 1. S-BRO also changed the chlorophyll fluorescence parameters Y (II), Y (NO), and Y (NPQ) to a greater extent than R-Bro. Transcription of genes psbO2, Lhcb3 and Lhcb6 was down-regulated in an enantioselective rhythm and S-BRO caused more serious influence, indicating that S-BRO did worse damage to the photosystem II (PSII) of A. thaliana than R-BRO. This study suggested that S-BRO disturbed the photosynthesis of plants to a larger extent than R-BRO and provided a new sight to evaluate the phytotoxicity of chiral herbicides. - Highlights: • It is necessary to assess the direct effects of PSII herbicides on photosynthesis. • Phytotoxicity of bromacil is investigated in an enantiomeric level. • Bromacil disturbed enantioselectively the photosystem II of Arabidopsis thaliana. • S-bromacil caused severer damage to photosynthesis of Arabidopsis than R-bromacil. • Photosynthesis should be considered for phytotoxicity assessment of herbicides.

  14. Phytotoxicity of chiral herbicide bromacil: Enantioselectivity of photosynthesis in Arabidopsis thaliana

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zunwei; Zou, Yuqin; Wang, Jia [MOE Key Laboratory of Environmental Remediation & Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Li, Meichao [Research Center of Analysis and Measurement, Zhejiang University of Technology, Hangzhou 310032 (China); Wen, Yuezhong, E-mail: wenyuezhong@zju.edu.cn [MOE Key Laboratory of Environmental Remediation & Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China)

    2016-04-01

    With the wide application of chiral herbicides and the frequent detection of photosystem II (PSII) herbicides, it is of great importance to assess the direct effects of PSII herbicides on photosynthesis in an enantiomeric level. In the present study, the enantioselective phytotoxicity of bromacil (BRO), typical photosynthesis inhibition herbicide, on Arabidopsis thaliana was investigated. The results showed that S-BRO exhibited a greater inhibition of electron transmission in photosystem I (PSI) of A. thaliana than R-BRO by inhibiting the transcription of fnr 1. S-BRO also changed the chlorophyll fluorescence parameters Y (II), Y (NO), and Y (NPQ) to a greater extent than R-Bro. Transcription of genes psbO2, Lhcb3 and Lhcb6 was down-regulated in an enantioselective rhythm and S-BRO caused more serious influence, indicating that S-BRO did worse damage to the photosystem II (PSII) of A. thaliana than R-BRO. This study suggested that S-BRO disturbed the photosynthesis of plants to a larger extent than R-BRO and provided a new sight to evaluate the phytotoxicity of chiral herbicides. - Highlights: • It is necessary to assess the direct effects of PSII herbicides on photosynthesis. • Phytotoxicity of bromacil is investigated in an enantiomeric level. • Bromacil disturbed enantioselectively the photosystem II of Arabidopsis thaliana. • S-bromacil caused severer damage to photosynthesis of Arabidopsis than R-bromacil. • Photosynthesis should be considered for phytotoxicity assessment of herbicides.

  15. Production of phytotoxic cationic α-helical antimicrobial peptides in plant cells using inducible promoters.

    Directory of Open Access Journals (Sweden)

    Nuri Company

    Full Text Available Synthetic linear antimicrobial peptides with cationic α-helical structures, such as BP100, have potent and specific activities against economically important plant pathogenic bacteria. They are also recognized as valuable therapeutics and preservatives. However, highly active BP100 derivatives are often phytotoxic when expressed at high levels as recombinant peptides in plants. Here we demonstrate that production of recombinant phytotoxic peptides in transgenic plants is possible by strictly limiting transgene expression to certain tissues and conditions, and specifically that minimization of this expression during transformation and regeneration of transgenic plants is essential to obtain viable plant biofactories. On the basis of whole-genome transcriptomic data available online, we identified the Os.hsp82 promoter that fulfilled this requirement and was highly induced in response to heat shock. Using this strategy, we generated transgenic rice lines producing moderate yields of severely phytotoxic BP100 derivatives on exposure to high temperature. In addition, a threshold for gene expression in selected tissues and stages was experimentally established, below which the corresponding promoters should be suitable for driving the expression of recombinant phytotoxic proteins in genetically modified plants. In view of the growing transcriptomics data available, this approach is of interest to assist promoter selection for specific purposes.

  16. Identification and Phytotoxicity Assessment of Phenolic Compounds in Chrysanthemoides monilifera subsp. monilifera (Boneseed.

    Directory of Open Access Journals (Sweden)

    Md Abdullah Yousuf Al Harun

    Full Text Available Chrysanthemoides monilifera subsp. monilifera (boneseed, a weed of national significance in Australia, threatens indigenous species and crop production through allelopathy. We aimed to identify phenolic compounds produced by boneseed and to assess their phytotoxicity on native species. Phenolic compounds in water and methanol extracts, and in decomposed litter-mediated soil leachate were identified using HPLC, and phytotoxicity of identified phenolics was assessed (repeatedly through a standard germination bioassay on native Isotoma axillaris. The impact of boneseed litter on native Xerochrysum bracteatum was evaluated using field soil in a greenhouse. Collectively, we found the highest quantity of phenolic compounds in boneseed litter followed by leaf, root and stem. Quantity varied with extraction media. The rank of phenolics concentration in boneseed was in the order of ferulic acid > phloridzin > catechin > p-coumaric acid and they inhibited germination of I. axillaris with the rank of ferulic acid > catechin > phloridzin > p-coumaric acid. Synergistic effects were more severe compared to individual phenolics. The litter-mediated soil leachate (collected after15 days exhibited strong phytotoxicity to I. axillaris despite the level of phenolic compounds in the decomposed leachate being decreased significantly compared with their initial level. This suggests the presence of other unidentified allelochemicals that individually or synergistically contributed to the phytotoxicity. Further, the dose response phytotoxic impacts exhibited by the boneseed litter-mediated soil to native X. bracteatum in a more naturalistic greenhouse experiment might ensure the potential allelopathy of other chemical compounds in the boneseed invasion. The reduction of leaf relative water content and chlorophyll level in X. bracteatum suggest possible mechanisms underpinning plant growth inhibition caused by boneseed litter allelopathy. The presence of a substantial

  17. Identification and Phytotoxicity Assessment of Phenolic Compounds in Chrysanthemoides monilifera subsp. monilifera (Boneseed).

    Science.gov (United States)

    Al Harun, Md Abdullah Yousuf; Johnson, Joshua; Uddin, Md Nazim; Robinson, Randall W

    2015-01-01

    Chrysanthemoides monilifera subsp. monilifera (boneseed), a weed of national significance in Australia, threatens indigenous species and crop production through allelopathy. We aimed to identify phenolic compounds produced by boneseed and to assess their phytotoxicity on native species. Phenolic compounds in water and methanol extracts, and in decomposed litter-mediated soil leachate were identified using HPLC, and phytotoxicity of identified phenolics was assessed (repeatedly) through a standard germination bioassay on native Isotoma axillaris. The impact of boneseed litter on native Xerochrysum bracteatum was evaluated using field soil in a greenhouse. Collectively, we found the highest quantity of phenolic compounds in boneseed litter followed by leaf, root and stem. Quantity varied with extraction media. The rank of phenolics concentration in boneseed was in the order of ferulic acid > phloridzin > catechin > p-coumaric acid and they inhibited germination of I. axillaris with the rank of ferulic acid > catechin > phloridzin > p-coumaric acid. Synergistic effects were more severe compared to individual phenolics. The litter-mediated soil leachate (collected after15 days) exhibited strong phytotoxicity to I. axillaris despite the level of phenolic compounds in the decomposed leachate being decreased significantly compared with their initial level. This suggests the presence of other unidentified allelochemicals that individually or synergistically contributed to the phytotoxicity. Further, the dose response phytotoxic impacts exhibited by the boneseed litter-mediated soil to native X. bracteatum in a more naturalistic greenhouse experiment might ensure the potential allelopathy of other chemical compounds in the boneseed invasion. The reduction of leaf relative water content and chlorophyll level in X. bracteatum suggest possible mechanisms underpinning plant growth inhibition caused by boneseed litter allelopathy. The presence of a substantial quantity of free

  18. Catechol-O-Methyltransferase Genotypes and Parenting Influence on Long-Term Executive Functioning After Moderate to Severe Early Childhood Traumatic Brain Injury: An Exploratory Study.

    Science.gov (United States)

    Kurowski, Brad G; Treble-Barna, Amery; Zang, Huaiyu; Zhang, Nanhua; Martin, Lisa J; Yeates, Keith Owen; Taylor, H Gerry; Wade, Shari L

    To examine catechol-O-methyltransferase (COMT) rs4680 genotypes as moderators of the effects of parenting style on postinjury changes in parent behavior ratings of executive dysfunction following moderate to severe early childhood traumatic brain injury. Research was conducted in an outpatient setting. Participants included children admitted to hospital with moderate to severe traumatic brain injury (n = 55) or orthopedic injuries (n = 70) between ages 3 and 7 years. Prospective cohort followed over 7 years postinjury. Parenting Practices Questionnaire and the Behavior Rating Inventory of Executive Functioning obtained at baseline, 6, 12, and 18 months, and 3.5 and 6.8 years postinjury. DNA was collected from saliva samples, purified using the Oragene (DNA Genotek, Ottawa, Ontario, Canada) OG-500 self-collection tubes, and analyzed using TaqMan (Applied Biosystems, Thermo Fisher Scientific, Waltham, Massachusetts) assay protocols to identify the COMT rs4680 polymorphism. Linear mixed models revealed a significant genotype × parenting style × time interaction (F = 5.72, P = .02), which suggested that the adverse effects of authoritarian parenting on postinjury development of executive functioning were buffered by the presence of the COMT AA genotype (lower enzyme activity, higher dopamine levels). There were no significant associations of executive functioning with the interaction between genotype and authoritative or permissive parenting ratings. The lower activity COMT rs4680 genotype may buffer the negative effect of authoritarian parenting on long-term executive functioning following injury in early childhood. The findings provide preliminary evidence for associations of parenting style with executive dysfunction in children and for a complex interplay of genetic and environmental factors as contributors to decreases in these problems after traumatic injuries in children. Further investigation is warranted to understand the interplay among genetic and

  19. Phytotoxic Activities of Mediterranean Essential Oils

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Rolim de Almeida

    2010-06-01

    Full Text Available Twelve essential oils from Mediterranean aromatic plants were tested for their phytotoxic activity, at different doses, against the germination and the initial radicle growth of seeds of Raphanus sativus, Lactuca sativa and Lepidium sativum. The essential oils were obtained from Hyssopus officinalis, Lavandula angustifolia, Majorana hortensis, Melissa officinalis, Ocimum basilicum, Origanum vulgare, Salvia officinalis and Thymus vulgaris (Lamiaceae, Verbena officinalis (Verbenaceae, Pimpinella anisum, Foeniculum vulgare and Carum carvi (Apiaceae. The germination and radicle growth of tested seeds were affected in different ways by the oils. Thyme, balm, vervain and caraway essential oils were more active against both germination and radicle elongation.

  20. Evaluation of heavy metal complex phytotoxicity

    Directory of Open Access Journals (Sweden)

    Vita Vasilyevna Datsenko

    2016-07-01

    Full Text Available The experimental data dealing with the effect of heavy metals contained in the technogenic contaminated soils on plant objects under controlled conditions was discussed. The aim of this work is to define the quantitative indicators of copper and zinc potential phytotoxicity, namely germination energy, simultaneous germination and duration of the test plants. It was found that the activity of the test plant growth is linked with copper and zinc complex action. Joint effect of copper and zinc is manifested both in inhibition of lettuce growth and determined, above all, by the nature contamination, soil properties and biological specificity of the test plants.

  1. Failure in Pantomime Action Execution Correlates with the Severity of Social Behavior Deficits in Children with Autism: A Praxis Study

    Science.gov (United States)

    Gizzonio, Valentina; Avanzini, Pietro; Campi, Cristina; Orivoli, Sonia; Piccolo, Benedetta; Cantalupo, Gaetano; Tassinari, Carlo Alberto; Rizzolatti, Giacomo; Fabbri-Destro, Maddalena

    2015-01-01

    Here we describe the performance of children with autism, their siblings, and typically developing children using the Florida Apraxia Battery. Children with autism showed the lowest performance in all sections of the test. They were mostly impaired in pantomime actions execution on imitation and on verbal command, and in imitation of meaningless…

  2. What to Wear to a Severance Party: A Former Corporate Executive Reflects on Her Own Downsizing Experience

    Science.gov (United States)

    Cumberland, Denise M.

    2013-01-01

    A corporate executive provides an amusing and reflective account on her experience of being downsized. This "day in the life" perspective documents the feelings of an individual who found herself served with "divorce papers" from a job that had, in many ways, defined her identity. Her personal story shines the spotlight on…

  3. Bioassay of naturally occurring allelochemicals for phytotoxicity.

    Science.gov (United States)

    Leather, G R; Einhellig, F A

    1988-10-01

    The bioassay has been one of the most widely used tests to demonstrate allelopathic activity. Often, claims that a particular plant species inhibits the growth of another are based entirely on the seed germination response to solvent extracts of the suspected allelopathic plant; few of these tests are of value in demonstrating allelopathy under natural conditions. The veracity of the bioassay for evaluating naturally occurring compounds for phytotoxicity depends upon the physiological and biochemical response capacity of the bioassay organism and the mechanism(s) of action of the allelochemicals. The possibility that more than one allelochemical, acting in concert at very low concentrations, may be responsible for an observed allelopathic effect makes it imperative that bioassays be extremely sensitive to chemical growth perturbation agents. Among the many measures of phytotoxicity of allelochemicals, the inhibition (or stimulation) of seed germination, radicle elongation, and/or seedling growth have been the parameters of choice for most investigations. Few of these assays have been selected with the view towards the possible mechanism of the allelopathic effect.

  4. Phytotoxic potential of Onopordum acanthium L. (Asteraceae).

    Science.gov (United States)

    Watanabe, Yusuke; Novaes, Paula; Varela, Rosa M; Molinillo, José M G; Kato-Noguchi, Hisashi; Macías, Francisco A

    2014-08-01

    Onopordum acanthium L. (Asteraceae) is a plant native to southern Europe and southwestern Asia, but it is invasive in disturbed areas and agricultural fields around the world, causing many agronomic problems by interfering with crops or preventing animals from grazing on pastures. Allelopathy could be one of the reasons that this plant has spread over different continents. The aim of the present study was to bioprospect O. acanthium leaf extracts through the isolation and purification of allelopathic secondary metabolites with phytotoxicity to explain their invasive behavior. Phytotoxic activity was tested using etiolated wheat coleoptiles. The most active extract was selected to perform a bioassay-guided isolation of two flavonoids, pectolarigenin (1) and scutellarein 4'-methyl ether (2), and two sesquiterpene lactones, elemanolide 11(13)-dehydromelitensin β-hydroxyisobutyrate (3) and acanthiolide (4). All compounds were isolated for the first time from O. acanthium, and acanthiolide (4) is described for the first time. Compound 3 strongly inhibited the growth of wheat coleoptiles and 1 showed an intermediate effect. The results indicate that these compounds could contribute to the invasion of O. acanthium in ecological systems and agricultural fields. Copyright © 2014 Verlag Helvetica Chimica Acta AG, Zürich.

  5. Phytotoxic potential of Drimys brasiliensis Miers for use in weed control

    Directory of Open Access Journals (Sweden)

    Simoni Anese

    2015-10-01

    Full Text Available This study aims to evaluate the phytotoxicity potential of leaf and root extracts of Drimys brasiliensis on the germination and seedling growth of Panicum maximum and Euphorbia heterophylla and its influence on metaxylem cell size in the seedling roots of the latter specie. The leaf and root extracts were fractionated by partition chromatography, and the hexane and ethyl acetate fractions obtained from each organ were evaluated at different concentrations for phytotoxic activity in several bioassays. In seedling growth tests, we compared the effects of these fractions with the herbicide oxyfluorfen. The hexane fraction of the root extracts showed a higher inhibitory potential on the germination and growth of weeds and reduced the average size of the metaxylem cells of E. heterophylla roots by more than 50%.The inhibitory effects of the root hexane fraction on seedling growth was similar to the herbicide, indicating that D. brasiliensis is a possible alternative form of control for the weed species examined.

  6. [Decision making and executive function in severe traumatic brain injured patients: validation of a decision-making task and correlated features].

    Science.gov (United States)

    Wiederkehr, S; Barat, M; Dehail, P; de Sèze, M; Lozes-Boudillon, S; Giroire, J-M

    2005-02-01

    At the chronic stage, severe traumatic brain injured (TBI) patients experience difficulty in making decisions. Several studies have demonstrated the involvement of the prefrontal cortex, in particular the orbitofrontal region, in decision-making. The aim of the present study was to validate a decision-making task in this population and to ascertain whether the components of their dysexecutive syndrome may affect their decision-making and lead to difficulties for social rehabilitation. Fifteen TBI patients and 15 controlled subjects matched for age, sex and years of education were assessed by a battery of executive tests (GREFEX) and by the gambling task (GT). The TBI subjects performed significantly worse than the controlled group in five out of six GREFEX tests. The TBI choices are significantly more disadvantageous than the choices of the control group when considering the three last blocks of 20 cards of the GT. The GT total score correlated significantly with execution time of the Stroop interference condition and the Trail Making Task B, as well as with the two measures (correct sequence span and number of crossed boxes) of the double condition of Baddeley's task. We postulate that executive functioning (supervisory attentional system) influence performance in the gambling task through mechanisms of inhibitory control, divided attention and working memory. Thus, this task seems to be determined by multiple factors; the process of decision-making may depend on frontal integrity.

  7. Antimicrobial, Cytotoxic and Phytotoxic Potency of Ethyl Acetate ...

    African Journals Online (AJOL)

    The antifungal activity was determined by inhibitory effect on the growth of. Alternaria ... Results: The extract showed phytotoxic activity (at 95% level of significance) against Lemna minor ..... screening of various organic extracts of caesalpinia.

  8. Tabanone a new phytotoxic constituent of cogongrass (Imperta culindrica)

    Science.gov (United States)

    Cogongrass [Imperata cylindrica (L.) Beauv.] is a troublesome invasive weedy species with reported allelopathic properties. The phytotoxicity of different constituents isolated from roots and aerial parts of this species was evaluated on Lactuca sativa and Agrostis stolonifera. No significant phytot...

  9. Abscisic acid protects bean leaves from ozone-induced phytotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, R.A.; Adedipe, N.O.; Ormrod, D.P.

    1972-01-01

    Abscisic acid treatment of primary bean leaves caused a partial closure of stomates and thus considerably reduced the phytotoxicity of ozone. The symptoms of ozone-induced phytotoxicity in the water-treated leaves are a marked decrease in chlorophyll and slight decreases in the levels of protein and RNA. The evidence indicates that ozone injury to leaves is not metabolically related to normal leaf senescence.

  10. Phytotoxic substances with allelopathic activity may be central to the strong invasive potential of Brachiaria brizantha.

    Science.gov (United States)

    Kato-Noguchi, Hisashi; Kobayashi, Ai; Ohno, Osamu; Kimura, Fukiko; Fujii, Yoshiharu; Suenaga, Kiyotake

    2014-04-15

    The grass Brachiaria brizantha, native to eastern Africa, becomes naturalized and dominant quickly in the non-native areas. It was hypothesized that phytotoxic chemical interaction between this plant and native plants may play an important role in the invasion of B. brizantha. However, no potent phytotoxic substance has been reported in this species. Therefore, we investigated possible allelopathic activity and searched for phytotoxic substances with allelopathic activity in B. brizantha. An aqueous methanol extract of B. brizantha inhibited the growth of roots and shoots of garden cress (Lepidium sativum), lettuce (Lactuca sativa), timothy (Phleum pratense) and ryegrass (Lolium multiflorum) seedlings. The extract was purified by several chromatographic runs and three allelopathically active substances were isolated and identified by spectral analysis as (6R,9R)-3-oxo-α-ionol, (6R,9S)-3-oxo-α-ionol and 4-ketopinoresinol. (6R,9R)-3-Oxo-α-ionol and (6R,9S)-3-oxo-α-ionol inhibited root and shoot growth of garden cress at concentrations greater than 30 and 10 μM, respectively. The activity of (6R,9S)-3-oxo-α-ionol was 5.3- to 6.2-fold that of (6R,9R)-3-oxo-α-ionol. The stereochemistry of the hydroxyl group at position C-9 may be important for the inhibitory activities of those compounds. 4-Ketopinoresinol inhibited root and shoot growth of garden cress at concentrations greater than 30 μM. The growth inhibitory activity of (6R,9S)-3-oxo-α-ionol was the greatest and followed by 4-ketopinoresinol and (6R,9R)-3-oxo-α-ionol. These results suggest that those phytotoxic substances may contribute to the allelopathic effect caused by B. brizantha and may be involved in the invasion of B. brizantha. Copyright © 2013 Elsevier GmbH. All rights reserved.

  11. Composition of the volatile fraction of a sample of Brazilian green propolic and its phytotoxic activity.

    Science.gov (United States)

    Fernandes-Silva, Caroline C; Lima, Carolina A; Negri, Giuseppina; Salatino, Maria L F; Salatino, Antonio; Mayworm, Marco A S

    2015-12-01

    Propolis is a resinous material produced by honeybees, containing mainly beeswax and plant material. Despite the wide spectrum of biological activity of propolis, to our knowledge no studies have been carried out about phytotoxic properties of Brazilian propolis and its constituents. The aims of this study were to analyze the chemical composition and to evaluate the phytotoxic activity of the volatile fraction of a sample of Brazilian green propolis. Main constituents are the phenylpropanoid 3-prenylcinnamic acid allyl ester (26.3%) and the sesquiterpene spathulenol (23.4%). Several other sesquiterpenes and phenylpropanoids, in addition to linalool and α-terpineol (monoterpenes), were also detected. The activity of solutions of the volatile fraction at 1.0, 0.5 and 0.1% was tested on lettuce seeds and seedlings. The solution at 1% inhibited completely the seed germination and solutions at 0.1 and 0.5% reduced the germination rate index. The solution at 0.5% reduced the growth of the hypocotyl-radicle axis and the development of the cotyledon leaf. The chemical composition of the volatile fraction of this Brazilian green propolis is different from those previously described, and these results may contribute to a better understanding about the chemical variations in propolis. The volatile fraction of Brazilian green propolis influences both germination of seed lettuce and the growth of its seedlings, showing an phytotoxic potential. © 2014 Society of Chemical Industry.

  12. Extended Erythropoietin Treatment Prevents Chronic Executive Functional and Microstructural Deficits Following Early Severe Traumatic Brain Injury in Rats

    Directory of Open Access Journals (Sweden)

    Shenandoah Robinson

    2018-06-01

    Full Text Available Survivors of infant traumatic brain injury (TBI are prone to chronic neurological deficits that impose lifelong individual and societal burdens. Translation of novel interventions to clinical trials is hampered in part by the lack of truly representative preclinical tests of cognition and corresponding biomarkers of functional outcomes. To address this gap, the ability of a high-dose, extended, post-injury regimen of erythropoietin (EPO, 3000U/kg/dose × 6d to prevent chronic cognitive and imaging deficits was tested in a postnatal day 12 (P12 controlled-cortical impact (CCI model in rats, using touchscreen operant chambers and regional analysis of diffusion tensor imaging (DTI. Results indicate that EPO prevents functional injury and MRI injury after infant TBI. Specifically, subacute DTI at P30 revealed widespread microstructural damage that is prevented by EPO. Assessment of visual discrimination on a touchscreen operant chamber platform demonstrated that all groups can perform visual discrimination. However, CCI rats treated with vehicle failed to pass reversal learning, and perseverated, in contrast to sham and CCI-EPO rats. Chronic DTI at P90 showed EPO treatment prevented contralateral white matter and ipsilateral lateral prefrontal cortex damage. This DTI improvement correlated with cognitive performance. Taken together, extended EPO treatment restores executive function and prevents microstructural brain abnormalities in adult rats with cognitive deficits in a translational preclinical model of infant TBI. Sophisticated testing with touchscreen operant chambers and regional DTI analyses may expedite translation and effective yield of interventions from preclinical studies to clinical trials. Collectively, these data support the use of EPO in clinical trials for human infants with TBI.

  13. Phytotoxicity of polycyclic aromatic hydrocarbons to willow trees

    Energy Technology Data Exchange (ETDEWEB)

    Thygesen, R.S.; Trapp, S. [Environment and Resources DTU, Technical Univ. of Denmark, Lyngby (Denmark)

    2002-07-01

    The toxicity of PAH to willow trees (Salix alba, S. viminalis, S. viminalis x schwerinii) was investigated. Willow cuttings were grown in PAH-saturated hydroponic solution (naphthalene NAP, phenanthrene PHEN and benzo(a)pyrene BaP). Toxicity was related to aqueous solubility and was highest for NAP. PHEN did not show significant effects, except in one case. Exposure of trees to BaP showed no effect in two cases, but increased transpiration and growth in two others. High dosages of NAP were fatal for the trees, the lowest dosage significantly stimulated growth. Soil samples were taken from several PAH contaminated sites, among them gas works sites and a former sludge basin. The PAH contents ranged from 1.76 mg/kg to 1451 mg/kg. None of the soils was lethally toxic to the trees, and difference between growth in control soils and growth in PAH contaminated soils was not apparent. Growth and water use efficiency were positively, but not significantly correlated to the PAH content of the soils. Outdoor growth of willows and poplars on the former sludge basin in Valby was monitored, with willows growing faster than poplars (Populus trichocarpa). Phytotoxic effects could be observed at some willows at the Valby sludge basin, but it is not sure whether these effects can be contributed to PAH. (orig.)

  14. Phytotoxicity, bioaccumulation and degradation of isoproturon in green algae.

    Science.gov (United States)

    Bi, Yan Fang; Miao, Shan Shan; Lu, Yi Chen; Qiu, Chong Bin; Zhou, You; Yang, Hong

    2012-12-01

    Isoproturon (IPU) is a pesticide used for protection of land crops from weed or pathogen attack. Recent survey shows that IPU has been detected as a contaminant in aquatic systems and may have negative impact on aquatic organisms. To understand the phytotoxicity and potential accumulation and degradation of IPU in algae, a comprehensive study was performed with the green alga Chlamydomonas reinhardtii. Algae exposed to 5-50 μg L(-1) IPU for 3d displayed progressive inhibition of cell growth and reduced chlorophyll fluorescence. Time-course experiments with 25 μg L(-1) IPU for 6d showed similar growth responses. The 72 h EC50 value for IPU was 43.25 μg L(-1), NOEC was 5 μg L(-1) and LOEC was 15 μg L(-1). Treatment with IPU induced oxidative stress. This was validated by a group of antioxidant enzymes, whose activities were promoted by IPU exposure. The up-regulation of several genes coding for the enzymes confirmed the observation. IPU was shown to be readily accumulated by C. reinhardtii. However, the alga showed a weak ability to degrade IPU accumulated in its cells, which was best presented at the lower concentration (5 μg L(-1)) of IPU in the medium. The imbalance of accumulation and degradation of IPU may be the cause that resulted in the detrimental growth and cellular damage. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Phytotoxic substance with allelopathic activity in Brachiaria decumbens.

    Science.gov (United States)

    Kobayashi, Ai; Kato-Noguchi, Hisashi

    2015-05-01

    The grass Brachiaria decumbens becomes naturalized and quickly dominant in non-native areas. It was hypothesized that phytotoxic substances of plants may contribute to the domination and invasion of the plants. However, no potent phytotoxic substance has been reported in B. decumbens. Therefore, we searched for phytotoxic substances with allelopathic activity in this species. An aqueous methanol extract of B. decumbens inhibited the growth of roots and shoots of cress (Lepidium sativum), lettuce (Lactuca sativa), timothy (Phleum pratense) and ryegrass (Lolium multiflorum) seedlings. The extract was then purified using chromatographic methods and a phytotoxic substance with allelopathic activity was isolated and identified by spectral analysis as (6R,9S)-3-oxo-α-ionol. These results suggest that this compound may contribute to the allelopathic effect caused by the B. decumbens extract and may be in part responsible for the invasion and domination of B. decumbens. Two other Brachiaria species, B. brizantha and a Brachiaria hybrid were also confirmed to contain (6R,9S)-3-oxo-α-ionol. Therefore, this compound may play an important role in the phytotoxicity of the Brachiaria species.

  16. PLANT CONTAMINATION AND PHYTOTOXICITY DUE TO HEAVY METALS FROM SOIL AND WATER

    Directory of Open Access Journals (Sweden)

    Judith Prieto Mendez

    2008-12-01

    Full Text Available High levels of heavy metals, such as: lead, nickel, cadmium and manganese, which are present in soil and wastewater used for agricultural irrigation, are due to the fact that these metals can be accumulated into these systems, of main importance for agriculture. Because of its non-biodegradability features, toxicity effects onto several crops and consequences on their bio-availability, this may result hazardous. This literature survey highlights and remarks relative sensitivity of some plants before heavy metals presence and crops trend to accumulate them, emphasizing aspects related to some soil physicochemical characteristics and heavy metals phyto-toxicity.

  17. Modelling the effect of autotoxicity on density-dependent phytotoxicity.

    Science.gov (United States)

    Sinkkonen, A

    2007-01-21

    An established method to separate resource competition from chemical interference is cultivation of monospecific, even-aged stands. The stands grow at several densities and they are exposed to homogenously spread toxins. Hence, the dose received by individual plants is inversely related to stand density. This results in distinguishable alterations in dose-response slopes. The method is often recommended in ecological studies of allelopathy. However, many plant species are known to release autotoxic compounds. Often, the probability of autotoxicity increases as sowing density increases. Despite this, the possibility of autotoxicity is ignored when experiments including monospecific stands are designed and when their results are evaluated. In this paper, I model mathematically how autotoxicity changes the outcome of dose-response slopes as different densities of monospecific stands are grown on homogenously phytotoxic substrata. Several ecologically reasonable relations between plant density and autotoxin exposure are considered over a range of parameter values, and similarities between different relations are searched for. The models indicate that autotoxicity affects the outcome of density-dependent dose-response experiments. Autotoxicity seems to abolish the effects of other phytochemicals in certain cases, while it may augment them in other cases. Autotoxicity may alter the outcome of tests using the method of monospecific stands even if the dose of autotoxic compounds per plant is a fraction of the dose of non-autotoxic phytochemicals with similar allelopathic potential. Data from the literature support these conclusions. A faulty null hypothesis may be accepted if the autotoxic potential of a test species is overlooked in density-response experiments. On the contrary, if test species are known to be non-autotoxic, the method of monospecific stands does not need fine-tuning. The results also suggest that the possibility of autotoxicity should be investigated in

  18. A novel approach for phytotoxicity assessment by CCD fluorescence imaging

    Czech Academy of Sciences Publication Activity Database

    Gavel, Alan; Maršálek, Blahoslav

    2004-01-01

    Roč. 19, - (2004), s. 429-432 ISSN 1520-4081 R&D Projects: GA AV ČR KSK6005114 Institutional research plan: CEZ:AV0Z6005908 Keywords : phytotoxicity * chlorophyll fluorescence * algal bioassay Subject RIV: EF - Botanics Impact factor: 1.373, year: 2004

  19. Phytotoxic activity of the methanol leaves extract of Paullinia pinnata ...

    African Journals Online (AJOL)

    The activity of the extract against the growth of Lemna minor was used to investigate the phytotoxic activity. The activity of the methanol extract of P. pinnata leaves against Lemna minor increased in a dose- dependent manner and was significant at 1000 μg/ml. Therefore, the methanol leaves extract of P. pinnata exhibited ...

  20. Antioxidant, Phytotoxic and Antiurease Activities, and Total Phenolic ...

    African Journals Online (AJOL)

    Purpose: To evaluate the antioxidant, phytotoxic and anti-urease properties of dichloromethane and methanol extracts of Conocarpus lancifolius in correlation with total phenolic and flavonoid contents. Methods: The whole plant (dried aerial parts and root) of Conocarpus lancifolius was extracted successively with ...

  1. Studies of teh phytotoxicity of the seed of phytochemical screening ...

    African Journals Online (AJOL)

    The phytotoxicity of the seed and phytochemical screening of the leaf of Ricinus communis were investigated. The secondary metabolites in the leaf were screened and identified. The leaves were sun dried, pulverized and sieved. The resulting powdered extract was subjected to phytochemical tests. A proximate analysis ...

  2. Nimbolide B and Nimbic Acid B, Phytotoxic Substances in Neem Leaves with Allelopathic Activity

    Directory of Open Access Journals (Sweden)

    Hisashi Kato-Noguchi

    2014-05-01

    Full Text Available Neem (Azadirachta indica has been widely used as a traditional medicine and several bioactive compounds have been isolated from this species, but to date no potent allelopathic active substance has been reported. Therefore, we investigated possible allelopathic property and phytotoxic substances with allelopathic activity in neem. An aqueous methanol extract of neem leaves inhibited the growth of roots and shoots of cress, lettuce, alfalfa, timothy, crabgrass, ryegrass, barnyard grass and jungle rice. The extracts were then purified by several chromatographic runs while monitoring the inhibitory activity and two phytotoxic substances were isolated. The chemical structures of the two substances were determined by spectral data to correspond to novel compounds, nimbolide B (1 and nimbic acid B (2. Nimbolide B inhibited the growth of cress and barnyard grass at concentrations greater than 0.1‒3.0 μM. Nimbic acid B inhibited the growth of cress and barnyard grass at concentrations greater than 0.3–1.0 μM. These results suggest that nimbolide B and nimbic acid B may contribute to the allelopathic effects caused by neem leaves.

  3. Execution and executability

    Science.gov (United States)

    Bradford, Robert W.; Harrison, Denise

    2015-09-01

    "We have a new strategy to grow our organization." Developing the plan is just the start. Implementing it in the organization is the real challenge. Many organizations don't fail due to lack of strategy; they struggle because it isn't effectively implemented. After working with hundreds of companies on strategy development, Denise and Robert have distilled the critical areas where organizations need to focus in order to enhance profitability through superior execution. If these questions are important to your organization, you'll find useful answers in the following articles: Do you find yourself overwhelmed by too many competing priorities? How do you limit how many strategic initiatives/projects your organization is working on at one time? How do you balance your resource requirements (time and money) with the availability of these resources? How do you balance your strategic initiative requirements with the day-to-day requirements of your organization?

  4. Essays in Executive Compensation

    NARCIS (Netherlands)

    D. Zhang (Dan)

    2012-01-01

    textabstractThis dissertation focuses on how executive compensation is designed and its implications for corporate finance and government regulations. Chapter 2 analyzes several proposals to restrict CEO compensation and calibrates two models of executive compensation that describe how firms would

  5. Phytotoxicity as an indicator of stability of broiler production residues.

    Science.gov (United States)

    Mendes, P M; Becker, R; Corrêa, L B; Bianchi, I; Dai Prá, M A; Lucia, T; Corrêa, E K

    2016-02-01

    Beddings used for successive broiler lots act as substrate to absorb water and feed from the excreta and may be subsequently used as agricultural fertilizers. This study evaluated the physicochemical characteristics and the phytotoxicity of beddings used to raise five consecutive broiler lots in five aviaries. Samples were collected for beddings not used yet and for beddings used at each of the five broiler lots. Lettuce and cucumber seeds were considered as phytotoxicity bioindicators. As beddings were used for greater number of lots, N, Ca, K, Mg and P contents generally increased, but the C content decreased, the pH alkalinized and humidity was reduced (P lettuce and cucumber seeds was reduced with increased bedding (P seeds. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Selenium inhibits the phytotoxicity of mercury in garlic (Allium sativum)

    International Nuclear Information System (INIS)

    Zhao, Jiating; Gao, Yuxi; Li, Yu-Feng; Hu, Yi; Peng, Xiaomin; Dong, Yuanxing; Li, Bai; Chen, Chunying; Chai, Zhifang

    2013-01-01

    To investigate the influence of selenium on mercury phytotoxicity, the levels of selenium and mercury were analyzed with inductively coupled plasma-mass spectrometry (ICP-MS) in garlic tissues upon exposure to different dosages of inorganic mercury (Hg 2+ ) and selenite (SeO 3 2− ) or selenate (SeO 4 2− ). The distributions of selenium and mercury were examined with micro-synchrotron radiation X-ray fluorescence (μ-SRXRF), and the mercury speciation was investigated with micro-X-ray absorption near edge structure (μ-XANES). The results show that Se at higher exposure levels (>1 mg/L of SeO 3 2− or SeO 4 2− ) would significantly inhibit the absorption and transportation of Hg when Hg 2+ levels are higher than 1 mg/L in culture media. SeO 3 2− and SeO 4 2− were found to be equally effective in reducing Hg accumulation in garlic. The inhibition of Hg uptake by Se correlates well with the influence of Se on Hg phytotoxicity as indicated by the growth inhibition factor. Elemental imaging using μ-SRXRF also shows that Se could inhibit the accumulation and translocation of Hg in garlic. μ-XANES analysis shows that Hg is mainly present in the forms of Hg–S bonding as Hg(GSH) 2 and Hg(Met) 2 . Se exposure elicited decrease of Hg–S bonding in the form of Hg(GSH) 2 , together with Se-mediated alteration of Hg absorption, transportation and accumulation, may account for attenuated Hg phytotoxicity by Se in garlic. -- Highlights: ► Hg phytotoxicity can be mitigated by Se supplement in garlic growth. ► Se can inhibit the accumulation and transportation of Hg in garlic tissues. ► Localization and speciation of Hg in garlic can be modified by Se

  7. Phytotoxic flavonoids from roots of Stellera chamaejasme L. (Thymelaeaceae).

    Science.gov (United States)

    Yan, Zhiqiang; Guo, Hongru; Yang, Jiayue; Liu, Quan; Jin, Hui; Xu, Rui; Cui, Haiyan; Qin, Bo

    2014-10-01

    Allelopathy, the negative effect on plants of chemicals released to the surroundings by a neighboring plant, is an important factor which contributes to the spread of some weeds in plant communities. In this field, Stellera chamaejasme L. (Thymelaeaceae) is one of the most toxic and ecologically-threatening weeds in some of the grasslands of north and west China. Bioassay-guided fractionation of root extracts of this plant led to the isolation of eight flavonoids 1-8, whose structures were elucidated by spectroscopic analysis. All compounds obtained, except 7-methoxylneochaejasmin A (4) and (+)-epiafzelechin (5), showed strong phytotoxic activity against Arabidopsis thaliana seedlings. Seedling growth was reduced by neochamaejasmin B (1), mesoneochamaejasmin A (2), chamaejasmenin C (3), genkwanol A (6), daphnodorin B (7) and dihydrodaphnodorin B (8) with IC50 values of 6.9, 12.1, 43.2, 74.8, 7.1 and 27.3μg/mL, respectively, and all of these compounds disrupted root development. Endogenous auxin levels at the root tips of the A. thaliana DR5::GUS transgenic line were largely reduced by compounds 1, 2 and 6-8, and were increased by compound 4. Moreover, the inhibition rate of A. thaliana auxin transport mutants pin2 and aux1-7 by compounds 1-8 were all lower than the wild type (Col-0). The influence of these compounds on endogenous auxin distribution is thus proposed as a critical factor for the phytotoxic effect. Compounds 1, 2, 4 and 8 were found in soils associated with S. chamaejasme, and these flavonoids also showed phytotoxicity to Clinelymus nutans L., an associated weed of S. chamaejasme. These results indicated that some phytotoxic compounds from roots of S. chamaejasme may be involved in the potential allelopathic behavior of this widespread weed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Antimicrobial, Cytotoxic, Phytotoxic and Antioxidant Potential of Heliotropium strigosum Willd.

    Science.gov (United States)

    Khurm, Muhammad; Chaudhry, Bashir A; Uzair, Muhammad; Janbaz, Khalid H

    2016-07-28

    Background: Heliotropium strigosum Willd. (Chitiphal) is a medicinally important herb that belongs to the Boraginaceae family. Traditionally, this plant was used in the medication therapy of various ailments in different populations of the world. The aim of the study is to probe the therapeutic aspects of H. strigosum described in the traditional folklore history of medicines. Methods: In the present study, the dichloromethane crude extract of this plant was screened to explore the antimicrobial, cytotoxic, phytotoxic and antioxidant potential of H. strigosum . For antibacterial, antifungal and antioxidant activities, microplate alamar blue assay (MABA), agar tube dilution method and diphenyl picryl hydrazine (DPPH) radical-scavenging assay were used, respectively. The cytotoxic and phytotoxic potential were demonstrated by using brine shrimp lethality bioassay and Lemna minor assay. Results: The crude extract displayed positive cytotoxic activity in the brine shrimp lethality assay, with 23 of 30 shrimps dying at the concentration of 1000 µg/mL. It also showed moderate phytotoxic potential with percent inhibition of 50% at the concentration of 1000 µg/mL. The crude extract exhibited no significant antibacterial activity against Staphylococcus aureus , Shigella flexneri , Escherichia coli and Pseudomonas aeruginosa . Non-significant antifungal and radical scavenging activity was also shown by the dichloromethane crude extract. Conclusion: It is recommended that scientists focus on the identification and isolation of beneficial bioactive constituents with the help of advanced scientific methodologies that seems to be helpful in the synthesis of new therapeutic agents of desired interest.

  9. Phytotoxicity of sarmentine isolated from long pepper (Piper longum) fruit.

    Science.gov (United States)

    Huang, Huazhang; Morgan, Christy M; Asolkar, Ratnakar N; Koivunen, Marja E; Marrone, Pamela G

    2010-09-22

    Discovery of novel natural herbicides has become crucial to overcome increasing weed resistance and environmental issues. In this article, we describe the finding that a methanol extract of dry long pepper (Piper longum L.) fruits is phytotoxic to lettuce (Lactuca sativa L.) seedlings. The bioassay-guided fractionation and purification of the crude extract led to isolation of sarmentine (1), a known compound, as the active principle. Phytotoxicity of 1 was examined with a variety of seedlings of field crops and weeds. Results indicated that 1 was a contact herbicide and possessed broad-spectrum herbicidal activity. Moreover, a series of sarmentine analogues were then synthesized to study the structure-activity relationship (SAR). SAR studies suggested that phytotoxicity of sarmentine and its analogues was specific due to chemical structures, i.e., the analogues of the acid moiety of 1 were active, but the amine and its analogues were inactive; the ester analogues and amide analogues with a primary amine of 1 were also inactive. In addition, quantification of 1 from different resources of the dry P. longum fruits using liquid chromatography-mass spectrometry showed a wide variation, ranging from almost zero to 0.57%. This study suggests that 1 has potential as an active lead molecule for synthesized herbicides as well as for bioherbicides derived from natural resources.

  10. Phytotoxicity Assessment of Certain Phytochemical Products Containing Pyrrolizidine Alkaloids

    Directory of Open Access Journals (Sweden)

    Cristina Șeremet Oana

    2013-10-01

    Full Text Available Introduction: Tussilago farfara (coltsfoot, Petasites hybridus (common butterbur, Senecio vernalis (eastern groundsel and Symphytum officinale (comfrey are species traditionally used in phytotherapy that besides the therapeutic compounds contain toxic pyrrolizidine alkaloids (PAs. The aim of the paper is to determine the total PAs content and the phytotoxicity of the above species. Material and methods: The quantitative determination of pyrrolizidine alkaloids is based on the stoichiometric reaction of protonated alkaloids with methyl orange. In acidic conditions the dye is released from the complex and its color is assessed spectrophotometrically using a linear regression curve of senecionine as a standard. The phytotoxicity was assessed by Triticum bioassay that studies the effect of the extracts (0.001-5.00%, w/v upon root elongation (inhibitory concentration - IC50 and on the karyokinetic film. Results: The highest amount of total PAs was found in Senecio vernalis (654.8 ± 35.96 μg/g dry plant and the lowest in Petasites hybridus. The lowest IC50 was found for Tussilago farfara followed by Petasites hybridus, Senecio vernalis, and Symphytum officinale. The results were supported by microscopic examination. Conclusions: The results of the spectrophotometric assay are consistent with the ones found in the literature. All extracts inhibited the elongation of the main root of wheat caryopses, however, no correlation between phytotoxicity and the PAs concentration could be emphasized

  11. Phytotoxicity of zinc and manganese to seedlings grown in soil contaminated by zinc smelting

    International Nuclear Information System (INIS)

    Beyer, W.N.; Green, C.E.; Beyer, M.; Chaney, R.L.

    2013-01-01

    Historic emissions from two zinc smelters have injured the forest on Blue Mountain near Palmerton, Pennsylvania, USA. Seedlings of soybeans and five tree species were grown in a greenhouse in a series of mixtures of smelter-contaminated and reference soils and then phytotoxic thresholds were calculated. As little as 10% Palmerton soil mixed with reference soil killed or greatly stunted seedlings of most species. Zinc was the principal cause of the phytotoxicity to the tree seedlings, although Mn and Cd may also have been phytotoxic in the most contaminated soil mixtures. Calcium deficiency seemed to play a role in the observed phytotoxicity. Exposed soybeans showed symptoms of Mn toxicity. A test of the effect of liming on remediation of the Zn and Mn phytotoxicity caused a striking decrease in Sr-nitrate extractable metals in soils and demonstrated that liming was critical to remediation and restoration. -- Highlights: •Zinc in smelter-contaminated acid soil was highly toxic to tree seedlings. •Phytotoxic thresholds (Zn in soil, leaves and roots) were estimated. •Liming greatly ameliorated the phytotoxicity. •Calcium deficiency played a role in the phytotoxicity. •Soybeans showed symptoms of Mn toxicity. -- This work estimates the phytotoxic thresholds of Zn to tree seedlings in smelter-contaminated soil and explains the interactions of Zn with Mn and Ca

  12. Mechanism of artemisinin phytotoxicity action: induction of reactive oxygen species and cell death in lettuce seedlings.

    Science.gov (United States)

    Yan, Zhi-Qiang; Wang, Dan-Dan; Ding, Lan; Cui, Hai-Yan; Jin, Hui; Yang, Xiao-Yan; Yang, Jian-She; Qin, Bo

    2015-03-01

    Artemisinin has been recognized as an allelochemical that inhibits growth of several plant species. However, its mode of action is not well clarified. In this study, the mechanism of artemisinin phytotoxicity on lettuce seedlings was investigated. Root and shoot elongation of lettuce seedlings were inhibited by artemisinin in a concentration-dependent manner. The compound effectively arrested cell division and caused loss of cell viability in root tips of lettuce. Overproduction of reactive oxygen species (ROS) was induced by artemisinin. Lipid peroxidation, proline overproduction and reduction of chlorophyll content in lettuce seedlings were found after treatments. These results suggested that artemisinin could induce ROS overproduction, which caused membrane lipids peroxidation and cell death, and impacted mitosis and physiological processes, resulting in growth inhibition of receptor plants. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  13. Hydrothermal Extraction of Microalgae Fatty Acid Influences Hydrochar Phytotoxicity

    Directory of Open Access Journals (Sweden)

    Christopher J. Ennis

    2017-08-01

    Full Text Available Hydrothermal carbonization (HTC of microalgae biomass for the production of triacylglycerides is a potentially valuable enabling technology for a waste water treatment-based integrated biorefinery. Here, HTC was used to treat Phaeodactylum tricornutum lipid-rich biomass producing a solid hydrochar from the surface of which adsorbed lipids were removed by hexane extraction following filtration of the solid hydrochar from the process liquid product. Approximately 7% of the input biomass was recovered and transesterified for qualitative and quantitative GC-MS analysis for fatty acid methyl esters. Transesterifiable lipids accounted for 94% of the material recovered by solvent extraction. Of the transesterified fatty acids (FA analyzed, the majority was monounsaturated (40.4% and saturated (37% C-16 FA. Other FA detected included saturated and monounsaturated C-18 (7.7 and 1.9% and saturated C-14 (5.3% and C-25 (1.5%. Thermal analysis (TGA/DSC of the hydrochar in air showed calorific values of 10.6 MJ kg−1 (delipidated hydrochar and 3.1 MJ kg−1 (non-delipidated hydrochar with the latter exhibiting the presence of volatalizable components. Germination trials were conducted to assess the potential phytotoxic effects of these hydrochars. Delipidated hydrochar showed a germination index of 73% suggesting the presence of some phytotoxicity. Non-delipidated hydrochar showed high germination index results of 102% (unground and 126% (ground. Taken together with the observation of reduced root hair proliferation in these two test conditions, this suggests the operation of a second phytotoxic effect that is removed by delipidation.

  14. Phytotoxicity of zinc and manganese to seedlings grown in soil contaminated by zinc smelting

    Science.gov (United States)

    Beyer, W.N.; Green, C.E.; Beyer, M.; Chaney, R.L.

    2013-01-01

    Historic emissions from two zinc smelters have injured the forest on Blue Mountain near Palmerton, Pennsylvania, USA. Seedlings of soybeans and five tree species were grown in a greenhouse in a series of mixtures of smelter-contaminated and reference soils and then phytotoxic thresholds were calculated. As little as 10% Palmerton soil mixed with reference soil killed or greatly stunted seedlings of most species. Zinc was the principal cause of the phytotoxicity to the tree seedlings, although Mn and Cd may also have been phytotoxic in the most contaminated soil mixtures. Calcium deficiency seemed to play a role in the observed phytotoxicity. Exposed soybeans showed symptoms of Mn toxicity. A test of the effect of liming on remediation of the Zn and Mn phytotoxicity caused a striking decrease in Sr-nitrate extractable metals in soils and demonstrated that liming was critical to remediation and restoration.

  15. Selenium inhibits the phytotoxicity of mercury in garlic (Allium sativum)

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Jiating [CAS Key Laboratory of Nuclear Analytical Techniques, Key Lab for Biomedical Effects of Nanomaterial and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Gao, Yuxi, E-mail: gaoyx@ihep.ac.cn [CAS Key Laboratory of Nuclear Analytical Techniques, Key Lab for Biomedical Effects of Nanomaterial and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Li, Yu-Feng; Hu, Yi; Peng, Xiaomin [CAS Key Laboratory of Nuclear Analytical Techniques, Key Lab for Biomedical Effects of Nanomaterial and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Dong, Yuanxing [Department of Physics, Xinzhou Teachers University, Xinzhou 034000 (China); Li, Bai; Chen, Chunying [CAS Key Laboratory of Nuclear Analytical Techniques, Key Lab for Biomedical Effects of Nanomaterial and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Chai, Zhifang, E-mail: chaizf@ihep.ac.cn [CAS Key Laboratory of Nuclear Analytical Techniques, Key Lab for Biomedical Effects of Nanomaterial and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

    2013-08-15

    To investigate the influence of selenium on mercury phytotoxicity, the levels of selenium and mercury were analyzed with inductively coupled plasma-mass spectrometry (ICP-MS) in garlic tissues upon exposure to different dosages of inorganic mercury (Hg{sup 2+}) and selenite (SeO{sub 3}{sup 2−}) or selenate (SeO{sub 4}{sup 2−}). The distributions of selenium and mercury were examined with micro-synchrotron radiation X-ray fluorescence (μ-SRXRF), and the mercury speciation was investigated with micro-X-ray absorption near edge structure (μ-XANES). The results show that Se at higher exposure levels (>1 mg/L of SeO{sub 3}{sup 2−} or SeO{sub 4}{sup 2−}) would significantly inhibit the absorption and transportation of Hg when Hg{sup 2+} levels are higher than 1 mg/L in culture media. SeO{sub 3}{sup 2−} and SeO{sub 4}{sup 2−} were found to be equally effective in reducing Hg accumulation in garlic. The inhibition of Hg uptake by Se correlates well with the influence of Se on Hg phytotoxicity as indicated by the growth inhibition factor. Elemental imaging using μ-SRXRF also shows that Se could inhibit the accumulation and translocation of Hg in garlic. μ-XANES analysis shows that Hg is mainly present in the forms of Hg–S bonding as Hg(GSH){sub 2} and Hg(Met){sub 2}. Se exposure elicited decrease of Hg–S bonding in the form of Hg(GSH){sub 2}, together with Se-mediated alteration of Hg absorption, transportation and accumulation, may account for attenuated Hg phytotoxicity by Se in garlic. -- Highlights: ► Hg phytotoxicity can be mitigated by Se supplement in garlic growth. ► Se can inhibit the accumulation and transportation of Hg in garlic tissues. ► Localization and speciation of Hg in garlic can be modified by Se.

  16. Executive Dysfunction

    Science.gov (United States)

    Rabinovici, Gil D.; Stephens, Melanie L.; Possin, Katherine L.

    2015-01-01

    Purpose of Review: Executive functions represent a constellation of cognitive abilities that drive goal-oriented behavior and are critical to the ability to adapt to an ever-changing world. This article provides a clinically oriented approach to classifying, localizing, diagnosing, and treating disorders of executive function, which are pervasive in clinical practice. Recent Findings: Executive functions can be split into four distinct components: working memory, inhibition, set shifting, and fluency. These components may be differentially affected in individual patients and act together to guide higher-order cognitive constructs such as planning and organization. Specific bedside and neuropsychological tests can be applied to evaluate components of executive function. While dysexecutive syndromes were first described in patients with frontal lesions, intact executive functioning relies on distributed neural networks that include not only the prefrontal cortex, but also the parietal cortex, basal ganglia, thalamus, and cerebellum. Executive dysfunction arises from injury to any of these regions, their white matter connections, or neurotransmitter systems. Dysexecutive symptoms therefore occur in most neurodegenerative diseases and in many other neurologic, psychiatric, and systemic illnesses. Management approaches are patient specific and should focus on treatment of the underlying cause in parallel with maximizing patient function and safety via occupational therapy and rehabilitation. Summary: Executive dysfunction is extremely common in patients with neurologic disorders. Diagnosis and treatment hinge on familiarity with the clinical components and neuroanatomic correlates of these complex, high-order cognitive processes. PMID:26039846

  17. Phytotoxicity associated to microcystins: a review

    Directory of Open Access Journals (Sweden)

    MC Bittencourt-Oliveira

    Full Text Available Microcystins (MC are the most studied toxins of cyanobacteria since they are widely distributed and account for several cases of human and animal poisoning, being potent inhibitors of the serine/threonine protein phosphatases 1 (PP1 and 2A (PP2A. The phosphatases PP1 and PP2A are also present in plants, which may also suffer adverse effects due to the inhibition of these enzymes. In aquatic plants, biomass reduction is usually observed after absorption of cyanotoxins, which can bioaccumulate in its tissues. In terrestrial plants, the effects caused by microcystins vary from inhibition to stimulation as the individuals develop from seedling to adult, and include reduction of protein phosphatases 1 and 2A, oxidative stress, decreased photosynthetic activity and even cell apoptosis, as well as bioaccumulation in plant tissues. Thus, the irrigation of crop plants by water contaminated with microcystins is not only an economic problem but becomes a public health issue because of the possibility of food contamination, and this route of exposure requires careful monitoring by the responsible authorities.

  18. Accumulation and phytotoxicity of engineered nanoparticles to Cucurbita pepo.

    Science.gov (United States)

    Hawthorne, Joseph; Musante, Craig; Sinha, Saion K; White, Jason C

    2012-04-01

    The effect of bulk and engineered nanoparticle (NP) Ag, Au, Cu, Si, and C at 250 and 750 mg/L on zucchini biomass, transpiration, and element content was determined. The pH of bulk and NP solutions prior to plant growth frequently differed. Nanoparticle Cu solution pH was significantly higher than bulk Cu, whereas for Ag and C, the NPs had significantly lower pH. Plants were unaffected by Au, regardless of particle size or concentration. NP Ag reduced plant biomass and transpiration by 49-91% compared to equivalent bulk Ag. NP Si at 750 mg/L reduced plant growth and transpiration by 30-51% relative to bulk Si. Bulk and NP Cu were phytotoxic but much of the effect was alleviated by humic acid. The shoot Ag and Cu content did not differ based on particle size or concentration. The accumulation of bulk Au was greater than the NP, but humic acid increased the accumulation of NP and bulk Au by 5.6-fold and 80%, respectively. The uptake of NP Si was 5.6-6.5-fold greater than observed with the bulk element. These findings show that the NPs may have unique phytotoxicity or accumulation patterns and that solution properties can significantly impact particle fate and effects.

  19. Flavonolignans from Elymus natans L. and Phytotoxic Activities.

    Science.gov (United States)

    Liu, Quan; Wu, Chenghui; Peng, Aifeng; Gao, Kun; Chen, Jianjun; Li, Ya; Fu, Hua

    2017-02-22

    Elymus natans, a perennial gramineous grass, plays an important role in animal husbandry and environmental sustenance in the Qinghai-Tibet plateau as a result of its high forage quality and good adaptability to the local environment. A bioassay showed that the extracts of green grasses of E. natans (GG) exhibited stronger phytotoxic activities than withered grasses (WG) against crops and grasses. In view of the secondary metabolites, which may be responsible for the resistance of the plant, the chemical components of GG were investigated. The flavone tricin, E1, and 10 flavonolignans, E2-E11, including three new flavonolignans, E2, E10, and E11, were isolated and identified. As far as we know, this is the first report on the chemical constitutions of the plant until now. The contents of compounds E1 and E4-E7 in GG were significantly higher than those in WG in high-performance liquid chromatography analysis, and they also showed observably phytotoxic activities against lettuce and Festuca arundinacea.

  20. Phytotoxicity testing of winery wastewater for constructed wetland treatment.

    Science.gov (United States)

    Arienzo, Michele; Christen, Evan W; Quayle, Wendy C

    2009-09-30

    Rapid and inexpensive phytotoxicity bioassays for winery wastewater (WW) are important when designing winery wastewater treatment systems involving constructed wetlands. Three macrophyte wetland species (Phragmites australis, Schoenoplectus validus and Juncus ingens) were tested using a pot experiment simulating a wetland microcosm. The winery wastewater concentration was varied (0.5%, 5%, 10%, 25%, 50%, 75% and 100%) and pH was corrected for some concentrations using lime as an amendment. The tolerance of the three aquatic macrophytes species to winery wastewater was studied through biomass production, total chlorophyll and nitrogen, phosphorous and potassium tissue concentrations. The results showed that at greater than 25% wastewater concentration all the macrophytes died and that Phragmites was the least hardy species. At less than 25% wastewater concentration the wetland microcosms were effective in reducing chemical oxygen demand, phenols and total soluble solids. We also evaluated the performance of two laboratory phytotoxicity assays; (1) Garden Cress (Lepidium sativum), and (2) Onion (Allium coepa). The results of these tests revealed that the effluent was highly toxic with effective concentration, EC(50), inhibition values, as low as 0.25%. Liming the WW increased the EC(50) by 10 fold. Comparing the cress and onion bioassays with the wetland microcosm results indicated that the thresholds for toxicity were of the same order of magnitude. As such we suggest that the onion and cress bioassays could be effectively used in the wine industry for rapid wastewater toxicity assessment.

  1. The phytotoxic effects of present NH3 immissions

    International Nuclear Information System (INIS)

    Adaros, G.; Daemmgen, U.

    1994-01-01

    The phytotoxic effects of NH 3 have been known since the end of the previous century. The significance of ammonia as harmful substance or stressor even in ambient concentrations has been only realized and investigated during the last decades. This volume is aimed at accounting the effects produced by ambient doses of NH 3 . The entities relevant for the description of potential dose response relationships are discussed. The major source of potential dose response relationships are discussed. The major source of atmospheric pollution of ammonia and ammonium is intensive agriculture, in particular intensive cattle production. However, sources and transmission processes are not dealt with in this paper. Potential pathways of ammonia into the plants and the respective reaction mechanisms are discussed in detail. (orig./MG) [de

  2. Root uptake and phytotoxicity of nanosized molybdenum octahedral clusters

    International Nuclear Information System (INIS)

    Aubert, Tangi; Burel, Agnès; Esnault, Marie-Andrée; Cordier, Stéphane; Grasset, Fabien; Cabello-Hurtado, Francisco

    2012-01-01

    Highlights: ► We investigated the effect of nanosized Mo 6 clusters on the growth of rapeseed plants. ► The aggregation state of the clusters depends on the dispersion medium. ► The concentration-dependant toxicity of the clusters depends on aggregation state. ► We took into account the possible contribution to toxicity of dissolved ionic species. ► The root uptake of the clusters was followed by NanoSIMS. - Abstract: Here are examined the root uptake and phytotoxicity of octahedral hexamolybdenum clusters on rapeseed plants using the solid state compound Cs 2 Mo 6 Br 14 as cluster precursor. [Mo 6 Br 14 ] 2− cluster units are nanosized entities offering a strong and stable emission in the near-infrared region with numerous applications in biotechnology. To investigate cluster toxicity on rapeseed plants, two different culture systems have been set up, using either a water-sorbing suspension of cluster aggregates or an ethanol-sorbing solution of dispersed nanosized clusters. Size, shape, surface area and state of clusters in both medium were analyzed by FE-SEM, BET and XPS. The potential contribution of cluster dissolution to phytotoxicity was evaluated by ICP-OES and toxicity analysis of Mo, Br and Cs. We showed that the clusters did not affect seed germination but greatly inhibited plant growth. This inhibition was much more important when plants were treated with nanosized entities than with microsized cluster aggregates. In addition, nanosized clusters affected the root morphology in a different manner than microsized cluster aggregates, as shown by FE-SEM observations. The root penetration of the clusters was followed by secondary ion mass spectroscopy with high spatial resolution (NanoSIMS) and was also found to be much more important for treatments with nanosized clusters.

  3. Assessing biochar ecotoxicology for soil amendment by root phytotoxicity bioassays.

    Science.gov (United States)

    Visioli, Giovanna; Conti, Federica D; Menta, Cristina; Bandiera, Marianna; Malcevschi, Alessio; Jones, Davey L; Vamerali, Teofilo

    2016-03-01

    Soil amendment with biochar has been proposed as effective in improving agricultural land fertility and carbon sequestration, although the characterisation and certification of biochar quality are still crucial for widespread acceptance for agronomic purposes. We describe here the effects of four biochars (conifer and poplar wood, grape marc, wheat straw) at increasing application rates (0.5, 1, 2, 5, 10, 20, 50% w/w) on both germination and root elongation of Cucumis sativus L., Lepidium sativum L. and Sorghum saccharatum Moench. The tested biochars varied in chemical properties, depending on the type and quality of the initial feedstock batch, polycyclic aromatic hydrocarbons (PAHs) being high in conifer and wheat straw, Cd in poplar and Cu in grape marc. We demonstrate that electrical conductivity and Cu negatively affected both germination and root elongation at ≥5% rate biochar, together with Zn at ≥10% and elevated pH at ≥20%. In all species, germination was less sensitive than root elongation, strongly decreasing at very high rates of chars from grape marc (>10%) and wheat straw (>50%), whereas root length was already affected at 0.5% of conifer and poplar in cucumber and sorghum, with marked impairment in all chars at >5%. As a general interpretation, we propose here logarithmic model for robust root phytotoxicity in sorghum, based on biochar Zn content, which explains 66% of variability over the whole dosage range tested. We conclude that metal contamination is a crucial quality parameter for biochar safety, and that root elongation represents a stable test for assessing phytotoxicity at recommended in-field amendment rates (<1-2%).

  4. Root uptake and phytotoxicity of nanosized molybdenum octahedral clusters

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, Tangi [Solid State Chemistry and Materials Group, UMR CNRS 6226 Sciences Chimiques de Rennes, University of Rennes 1, 263 av. du General Leclerc, Campus de Beaulieu, 35042 Rennes (France); Burel, Agnes [Electronic Microscopy Department, University of Rennes 1, 2 av. du Professeur Leon-Bernard, Campus de Villejean, 35043 Rennes (France); Esnault, Marie-Andree [Mechanisms at the Origin of Biodiversity Team, UMR CNRS 6553 Ecobio, University of Rennes 1, 263 av. du General Leclerc, Campus de Beaulieu, 35042 Rennes (France); Cordier, Stephane; Grasset, Fabien [Solid State Chemistry and Materials Group, UMR CNRS 6226 Sciences Chimiques de Rennes, University of Rennes 1, 263 av. du General Leclerc, Campus de Beaulieu, 35042 Rennes (France); Cabello-Hurtado, Francisco, E-mail: francisco.cabello@univ-rennes1.fr [Mechanisms at the Origin of Biodiversity Team, UMR CNRS 6553 Ecobio, University of Rennes 1, 263 av. du General Leclerc, Campus de Beaulieu, 35042 Rennes (France)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer We investigated the effect of nanosized Mo{sub 6} clusters on the growth of rapeseed plants. Black-Right-Pointing-Pointer The aggregation state of the clusters depends on the dispersion medium. Black-Right-Pointing-Pointer The concentration-dependant toxicity of the clusters depends on aggregation state. Black-Right-Pointing-Pointer We took into account the possible contribution to toxicity of dissolved ionic species. Black-Right-Pointing-Pointer The root uptake of the clusters was followed by NanoSIMS. - Abstract: Here are examined the root uptake and phytotoxicity of octahedral hexamolybdenum clusters on rapeseed plants using the solid state compound Cs{sub 2}Mo{sub 6}Br{sub 14} as cluster precursor. [Mo{sub 6}Br{sub 14}]{sup 2-} cluster units are nanosized entities offering a strong and stable emission in the near-infrared region with numerous applications in biotechnology. To investigate cluster toxicity on rapeseed plants, two different culture systems have been set up, using either a water-sorbing suspension of cluster aggregates or an ethanol-sorbing solution of dispersed nanosized clusters. Size, shape, surface area and state of clusters in both medium were analyzed by FE-SEM, BET and XPS. The potential contribution of cluster dissolution to phytotoxicity was evaluated by ICP-OES and toxicity analysis of Mo, Br and Cs. We showed that the clusters did not affect seed germination but greatly inhibited plant growth. This inhibition was much more important when plants were treated with nanosized entities than with microsized cluster aggregates. In addition, nanosized clusters affected the root morphology in a different manner than microsized cluster aggregates, as shown by FE-SEM observations. The root penetration of the clusters was followed by secondary ion mass spectroscopy with high spatial resolution (NanoSIMS) and was also found to be much more important for treatments with nanosized clusters.

  5. Executive summary

    NARCIS (Netherlands)

    van Nimwegen, N.; van Nimwegen, N.; van der Erf, R.

    2009-01-01

    The Demography Monitor 2008 gives a concise overview of current demographic trends and related developments in education, the labour market and retirement for the European Union and some other countries. This executive summary highlights the major findings of the Demography Monitor 2008 and further

  6. Phytotoxicity of the combination of some insecticides and fungicides on the ornamental species Petunia sp.

    Directory of Open Access Journals (Sweden)

    Renata Bažok

    2016-12-01

    Full Text Available In the production of ornamental plants, it is often necessary to combine plant protection products (PPPs for simultaneous pest control. The use of a combination of PPPs often leads to phytotoxicity. The aim of this study was to determine the phytotoxicity of the combination of fungicides (azoxystrobin and cyprodinil + fludioxonil and insecticides based on abamectin and thiomethoxam on the ornamental plant Petunia sp. The PPPs are used at recommended and double doses. Based on the damage, phytotoxicity indices were calculated. Petunia plants are sensitive even when PPPs are used in recommended doses. Combinations of the both insecticides with the combined fungicide based on cyprodinil and fludioxinil can be advised to protect petunias only if one applies the recommended doses. All combinations of insecticides with a fungicide based on azoxystrobin should not be applied because there is a serious risk of phytotoxicity.

  7. Effect of sweet pepper cultivation on the content of phytotoxic phenolic compounds in substrates

    Directory of Open Access Journals (Sweden)

    Barbara Politycka

    2013-12-01

    Full Text Available The aim of the conducted study was to determine to what extent the cultivation of sweet pepper lowers the phytotoxicity of a substrate. The examined material was a highly phytotoxic substrate due to repeated cucumber growing on it. This substrate was a mixture of pine and beech bark, low peat and sawdust. Five sweet pepper cultivars: Amador, Bell Boy, Culinar, Poznańska Słodka and WSE 2/82 were planted. During vegetation of the sweet pepper phytotoxicity and phenolics levels were determined in the substrate. It was found that cultivation of sweet pepper had a significant effect on lowering phytotoxicity and phenolics content in the substrate. Among the five tested cultivars, the highest detoxicating ability was exhibited by Amador, Culinar and WSE 2/82 while the Poznańska Słodka did not show such abilities.

  8. Use of algal fluorescence for determination of phytotoxicity of heavy metals and pesticides as environmental pollutants.

    Science.gov (United States)

    Samson, G; Popovic, R

    1988-12-01

    The phytotoxicity of heavy metals and pesticides was studied by using the fluorescence induction from the alga Dunaliella tertiolecta. The complementary area calculated from the variable fluorescence induction was used as a direct parameter to estimate phytotoxicity. The value of this parameter was affected when algae were treated with different concentrations of mercury, copper, atrazine, DCMU, Dutox, and Soilgard. The toxic effect of these pollutants was estimated by monitoring the decrease in the complementary area, which reflects photosystem II photochemistry. Further, the authors have demonstrated the advantage of using the complementary area as a parameter of phytotoxicity over using variable fluorescence yield. The complementary area of algal fluorescence can be used as a simple and sensitive parameter in the estimation of the phytotoxicity of polluted water.

  9. Studies on cytotoxic, phytotoxic and volatile profile of the bark extract ...

    African Journals Online (AJOL)

    rams

    2013-10-23

    Oct 23, 2013 ... (Roxb.) Kurz. by GC-MS analysis and also to investigate the cytotoxic and phytotoxic activity of. Mallotus ... tannins, terpenoids, coumarins, benzopyrans and chalcones ..... Euphorbin I, a new dimeric hydrolyzable tannin from ...

  10. [Phytotoxic activity of chernozem saprophytic micromycetes: specificity, sorption and stability of phytotoxins in soil].

    Science.gov (United States)

    Svistova, I D; Shcherbakov, A P; Frolova, L O

    2003-01-01

    Micromycetes of the complex of typical chernozem saprotrophic fungi released phytotoxic metabolites into medium. The metabolites displayed their phytotoxic activities directly in soil. Evaluation of the toxicities, range of biological effects activities, and stabilities of phytotoxins in soil and the rates of their biodegradation allowed the species that can serve as indicators of chernozem microbial toxicosis to be selected, namely, Aspergillus clavatus, Fusarium solani, Talaromyces flavus, Penicillium rubrum, and P. funiculosum.

  11. Identification and Phytotoxicity Assessment of Phenolic Compounds in Chrysanthemoides monilifera subsp. monilifera (Boneseed)

    OpenAIRE

    Al Harun, Md Abdullah Yousuf; Johnson, Joshua; Uddin, Md Nazim; Robinson, Randall W.

    2015-01-01

    Chrysanthemoides monilifera subsp. monilifera (boneseed), a weed of national significance in Australia, threatens indigenous species and crop production through allelopathy. We aimed to identify phenolic compounds produced by boneseed and to assess their phytotoxicity on native species. Phenolic compounds in water and methanol extracts, and in decomposed litter-mediated soil leachate were identified using HPLC, and phytotoxicity of identified phenolics was assessed (repeatedly) through a stan...

  12. Healthcare. Executive Summary

    Science.gov (United States)

    Carnevale, Anthony P.; Smith, Nicole; Gulish, Artem; Beach, Bennett H.

    2012-01-01

    This executive summary highlights several findings about healthcare. These are: (1) Healthcare is 18 percent of the U.S. economy, twice as high as in other countries; (2) There are two labor markets in healthcare: high-skill, high-wage professional and technical jobs and low-skill, low-wage support jobs; (3) Demand for postsecondary education in…

  13. Cyanobacterial toxins: modes of actions, fate in aquatic and soil ecosystems, phytotoxicity and bioaccumulation in agricultural crops.

    Science.gov (United States)

    Corbel, Sylvain; Mougin, Christian; Bouaïcha, Noureddine

    2014-02-01

    The occurrence of harmful cyanobacterial blooms in surface waters is often accompanied by the production of a variety of cyanotoxins. These toxins are designed to target in humans and animals specific organs on which they act: hepatotoxins (liver), neurotoxins (nervous system), cytotoxic alkaloids, and dermatotoxins (skin), but they often have important side effects too. When introduced into the soil ecosystem by spray irrigation of crops they may affect the same molecular pathways in plants having identical or similar target organs, tissues, cells or biomolecules. There are also several indications that terrestrial plants, including food crop plants, can bioaccumulate cyanotoxins and present, therefore, potential health hazards for human and animals. The number of publications concerned with phytotoxic effects of cyanotoxins on agricultural plants has increased recently. In this review, we first examine different cyanotoxins and their modes of actions in humans and mammals and occurrence of target biomolecules in vegetable organisms. Then we present environmental concentrations of cyanotoxins in freshwaters and their fate in aquatic and soil ecosystems. Finally, we highlight bioaccumulation of cyanotoxins in plants used for feed and food and its consequences on animals and human health. Overall, our review shows that the information on the effects of cyanotoxins on non-target organisms in the terrestrial environment is particularly scarce, and that there are still serious gaps in the knowledge about the fate in the soil ecosystems and phytotoxicity of these toxins. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Production of Phytotoxic Metabolite Using Biphasic Fermentation System from Strain C1136 of Lasiodiplodia pseudotheobromae, a Potential Bioherbicidal Agent

    OpenAIRE

    Charles Oluwaseun ADETUNJI; Julius Kola OLOKE; Gandham PRASAD; Moses ABALAKA; Emenike Onyebum IROKANULO

    2017-01-01

    Formulation of effective and environmental friendly bioherbicides depends on the type of fermentation medium used for the production of phytotoxic metabolites. The effect of biomass, colony forming unit and the phytotoxic metabolite produced from the biphasic fermentation was carried out, while the phytotoxic metabolite was tested in vivo and in-vitro on Echinochola crus-galli and dicotyledonous Chromolaena odorata. The mutant strain of Lasiodiplodia pseudotheobromae C1136 (Lp90) produced th...

  15. Phytotoxicity assessment of a methanolic coal dust extract in Lemna minor.

    Science.gov (United States)

    Coronado-Posada, Nadia; Cabarcas-Montalvo, Maria; Olivero-Verbel, Jesus

    2013-09-01

    Coal mining generates negative effects on environment, human health, hydrodynamics of mining areas and biodiversity. However, the impacts of this activity are less known in plants. Lemna minor is one of the most commonly used plants in aquatic toxicity tests due to its ubiquitous distribution in ponds and lakes, culture conditions and the free-floating habitat that exposes it to hydrophobic as well as dissolved compounds. The goal of this research was to evaluate the effects of a methanolic coal dust extract on L. minor. Macrophytes were exposed to six different concentrations of coal extract (from 7.81 to 250 mg/L) for 5 days, following the OECD test guideline 221. The coal extract had a half inhibitory concentration (IC50) of 99.66 (184.95-54.59) mg/L for the number of fronds. Several signs of toxicity such as chlorosis, reduction in the size of the fronds, abscission of fronds and roots, and the presence of necrotic tissues were observed at concentrations lower than the IC50. Preliminary Gas Chromatography-Mass Spectrometry analysis of the coal dust extract revealed the presence of several compounds, including, among others, alkanes, carboxylic acids and polycyclic aromatic hydrocarbons (PAHs), these lasts, may be responsible for some of the observed effects. These results demonstrated that coal dust has phytotoxic effects and should not be considered as an inert material. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Genetic analyses of the stability of executive functioning during childhood.

    NARCIS (Netherlands)

    Polderman, T.J.C.; Posthuma, D.; de Sonneville, L.M.J.; Stins, J.F.; Verhulst, F.C.; Boomsma, D.I.

    2007-01-01

    Executive functioning is an umbrella term for several related cognitive functions like selective- and sustained attention, working memory, and inhibition. Little is known about the stability of executive functioning during childhood. In this study the longitudinal stability of executive functioning

  17. Executive summary

    International Nuclear Information System (INIS)

    1981-02-01

    This paper is an 'executive summary' of work undertaken to review proposals for transport, handling and emplacement of high level radioactive wastes in an underground repository, appropriate to the U.K. context, with particular reference to: waste block size and configuration; self-shielded or partially-shielded block; stages of disposal; transportation within the repository; emplacement in vertical holes or horizontal tunnels; repository access by adit, incline or shaft; and costs. The paper contains a section on general conclusions and recommendations. (U.K.)

  18. Graphene oxide amplifies the phytotoxicity of arsenic in wheat

    Science.gov (United States)

    Hu, Xiangang; Kang, Jia; Lu, Kaicheng; Zhou, Ruiren; Mu, Li; Zhou, Qixing

    2014-08-01

    Graphene oxide (GO) is widely used in various fields and is considered to be relatively biocompatible. Herein, ``indirect'' nanotoxicity is first defined as toxic amplification of toxicants or pollutants by nanomaterials. This work revealed that GO greatly amplifies the phytotoxicity of arsenic (As), a widespread contaminant, in wheat, for example, causing a decrease in biomass and root numbers and increasing oxidative stress, which are thought to be regulated by its metabolisms. Compared with As or GO alone, GO combined with As inhibited the metabolism of carbohydrates, enhanced amino acid and secondary metabolism and disrupted fatty acid metabolism and the urea cycle. GO also triggered damage to cellular structures and electrolyte leakage and enhanced the uptake of GO and As. Co-transport of GO-loading As and transformation of As(V) to high-toxicity As(III) by GO were observed. The generation of dimethylarsinate, produced from the detoxification of inorganic As, was inhibited by GO in plants. GO also regulated phosphate transporter gene expression and arsenate reductase activity to influence the uptake and transformation of As, respectively. Moreover, the above effects of GO were concentration dependent. Given the widespread exposure to As in agriculture, the indirect nanotoxicity of GO should be carefully considered in food safety.

  19. Phytotoxicity of silver nanoparticles to Lemna minor L

    Energy Technology Data Exchange (ETDEWEB)

    Gubbins, Eva J. [Department of Geography and Environmental Science, University of Birmingham, Edgbaston, Birmingham, B15 2TT (United Kingdom); Batty, Lesley C., E-mail: l.c.batty@bham.ac.uk [Department of Geography and Environmental Science, University of Birmingham, Edgbaston, Birmingham, B15 2TT (United Kingdom); Lead, Jamie R. [Department of Geography and Environmental Science, University of Birmingham, Edgbaston, Birmingham, B15 2TT (United Kingdom)

    2011-06-15

    The use of silver nanoparticles (AgNPs) in commercial products has increased significantly in recent years. Although there has been some attempt to determine the toxic effects of AgNPs, there is little information on aquatic plants which have a vital role in ecosystems. This study reports the use of Lemna minor L. clone St to investigate the phytotoxicity of AgNPs under modified OECD test conditions. AgNPs were synthesised, characterised and subsequently presented to the L. minor. Results showed that inhibition of plant growth was evident after exposure to small ({approx}20 nm) and larger ({approx}100 nm) AgNPs at low concentrations (5 {mu}g L{sup -1}) and this effect became more acute with a longer exposure time. There was a linear dose-response relationship after 14 d exposure. Using predicted environmental concentrations for wastewaters it was found that AgNPs may pose a significant potential risk to the environment. - Highlights: > Silver nanoparticles are toxic to Lemna minor at concentrations of 5 {mu}g L{sup -1}. > The effect of silver nanoparticles varies with size and concentration. > Standard toxicity tests are not appropriate for application to NPs. > Silver nanoparticles pose a potential environmental risk based on modelled environmental concentrations. - Silver nanoparticles are toxic to Lemna minor at low concentrations and constitute a significant environmental risk.

  20. Phytotoxicity of silver nanoparticles to Lemna minor L

    International Nuclear Information System (INIS)

    Gubbins, Eva J.; Batty, Lesley C.; Lead, Jamie R.

    2011-01-01

    The use of silver nanoparticles (AgNPs) in commercial products has increased significantly in recent years. Although there has been some attempt to determine the toxic effects of AgNPs, there is little information on aquatic plants which have a vital role in ecosystems. This study reports the use of Lemna minor L. clone St to investigate the phytotoxicity of AgNPs under modified OECD test conditions. AgNPs were synthesised, characterised and subsequently presented to the L. minor. Results showed that inhibition of plant growth was evident after exposure to small (∼20 nm) and larger (∼100 nm) AgNPs at low concentrations (5 μg L -1 ) and this effect became more acute with a longer exposure time. There was a linear dose-response relationship after 14 d exposure. Using predicted environmental concentrations for wastewaters it was found that AgNPs may pose a significant potential risk to the environment. - Highlights: → Silver nanoparticles are toxic to Lemna minor at concentrations of 5 μg L -1 . → The effect of silver nanoparticles varies with size and concentration. → Standard toxicity tests are not appropriate for application to NPs. → Silver nanoparticles pose a potential environmental risk based on modelled environmental concentrations. - Silver nanoparticles are toxic to Lemna minor at low concentrations and constitute a significant environmental risk.

  1. Phytotoxicity and Plant Productivity Analysis of Tar-Enriched Biochars

    Science.gov (United States)

    Keller, M. L.; Masiello, C. A.; Dugan, B.; Rudgers, J. A.; Capareda, S. C.

    2008-12-01

    Biochar is one of the three by-products obtained by the pyrolysis of organic material, the other two being syngas and bio-oil. The pyrolysis of biomass has generated a great amount of interest in recent years as all three by-products can be put toward beneficial uses. As part of a larger project designed to evaluate the hydrologic impact of biochar soil amendment, we generated a biochar through fast pyrolysis (less than 2 minutes) of sorghum stock at 600°C. In the initial biochar production run, the char bin was not purged with nitrogen. This inadvertent change in pyrolysis conditions produced a fast-pyrolysis biochar enriched with tars. We chose not to discard this batch, however, and instead used it to test the impact of tar-enriched biochars on plants. A suite of phytotoxicity tests were run to assess the effects of tar-rich biochar on plant germination and plant productivity. We designed the experiment to test for negative effects, using an organic carbon and nutrient-rich, greenhouse- optimized potting medium instead of soil. We used Black Seeded Simpson lettuce (Lactuca sativa) as the test organism. We found that even when tars are present within biochar, biochar amendment up to 10% by weight caused increased lettuce germination rates and increased biomass productivity. In this presentation, we will report the statistical significance of our germination and biomass data, as well as present preliminary data on how biochar amendment affects soil hydrologic properties.

  2. Pseudomonas orientalis F9: A Potent Antagonist against Phytopathogens with Phytotoxic Effect in the Apple Flower

    Directory of Open Access Journals (Sweden)

    Veronika Zengerer

    2018-02-01

    Full Text Available In light of public concerns over the use of pesticides and antibiotics in plant protection and the subsequent selection for spread of resistant bacteria in the environment, it is inevitable to broaden our knowledge about viable alternatives, such as natural antagonists and their mode of action. The genus Pseudomonas is known for its metabolic versatility and genetic plasticity, encompassing pathogens as well as antagonists. We characterized strain Pseudomonas orientalis F9, an isolate from apple flowers in a Swiss orchard, and determined its antagonistic activity against several phytopathogenic bacteria, in particular Erwinia amylovora, the causal agent of fire blight. P. orientalis F9 displayed antagonistic activity against a broad suite of phytopathogenic bacteria in the in vitro tests. The promising results from this analysis led to an ex vivo assay with E. amylovora CFBP1430Rif and P. orientalis F9 infected detached apple flowers. F9 diminished the fire blight pathogen in the flowers but also revealed phytotoxic traits. The experimental results were discussed in light of the complete genome sequence of F9, which revealed the strain to carry phenazine genes. Phenazines are known to contribute to antagonistic activity of bacterial strains against soil pathogens. When tested in the cress assay with Pythium ultimum as pathogen, F9 showed results comparable to the known antagonist P. protegens CHA0.

  3. Pseudomonas orientalis F9: A Potent Antagonist against Phytopathogens with Phytotoxic Effect in the Apple Flower.

    Science.gov (United States)

    Zengerer, Veronika; Schmid, Michael; Bieri, Marco; Müller, Denise C; Remus-Emsermann, Mitja N P; Ahrens, Christian H; Pelludat, Cosima

    2018-01-01

    In light of public concerns over the use of pesticides and antibiotics in plant protection and the subsequent selection for spread of resistant bacteria in the environment, it is inevitable to broaden our knowledge about viable alternatives, such as natural antagonists and their mode of action. The genus Pseudomonas is known for its metabolic versatility and genetic plasticity, encompassing pathogens as well as antagonists. We characterized strain Pseudomonas orientalis F9, an isolate from apple flowers in a Swiss orchard, and determined its antagonistic activity against several phytopathogenic bacteria, in particular Erwinia amylovora , the causal agent of fire blight. P. orientalis F9 displayed antagonistic activity against a broad suite of phytopathogenic bacteria in the in vitro tests. The promising results from this analysis led to an ex vivo assay with E. amylovora CFBP1430 Rif and P. orientalis F9 infected detached apple flowers. F9 diminished the fire blight pathogen in the flowers but also revealed phytotoxic traits. The experimental results were discussed in light of the complete genome sequence of F9, which revealed the strain to carry phenazine genes. Phenazines are known to contribute to antagonistic activity of bacterial strains against soil pathogens. When tested in the cress assay with Pythium ultimum as pathogen, F9 showed results comparable to the known antagonist P. protegens CHA0.

  4. Accumulation and phytotoxicity of perfluorooctanoic acid in the model plant species Arabidopsis thaliana

    International Nuclear Information System (INIS)

    Yang, Xinping; Ye, Chengchen; Liu, Yu; Zhao, Fang-Jie

    2015-01-01

    Perfluorooctanoic acid (PFOA) is widely used in the manufacture of many industrial and household products. To assess the potential environmental risk of PFOA, its accumulation, translocation and phytotoxic effects were investigated using the model plant species Arabidopsis thaliana. Exposure to 18 μM PFOA-F in agar plates did not affect plant growth, but 181–1811 μM PFOA-F inhibited root and shoot growth. PFOA was more phytotoxic on shoot growth than NaF at the equivalent F concentration, with the latter having 3.9–7.6 times higher EC50 for shoot biomass than PFOA. PFOA was efficiently translocated from roots to shoots, where it existed as intact PFOA molecules without transformation evidenced by the 19 F NMR spectra. PFOA caused a significant increase in the concentration of H 2 O 2 and malondialdehyde (MDA) in shoots, indicating that oxidative stress is a likely cause of PFOA phytotoxicity. - Highlights: • PFOA is more phytotoxic on shoot growth than NaF at the equivalent F concentration. • PFOA is readily taken up and translocated from roots to shoots. • PFOA exists as intact molecules without transformation in Arabidopsis shoots. • PFOA causes oxidative stress in Arabidopsis shoots. - Perfluorooctanoic acid causes oxidative stress and is more phytotoxic on shoot growth than inorganic fluoride at the equivalent F concentration.

  5. Phytotoxicity evaluation and phytochemical analysis of three medicinally important plants from Pakistan.

    Science.gov (United States)

    Ullah, Nazif; Haq, Ihsan-Ul; Mirza, Bushra

    2015-05-01

    This work examines the crude methanolic extracts of three medicinally important plants native to Pakistan for potent phytotoxic activities and important phytochemicals. These plants include Euphorbia wallichii, Bergenia ciliata and Phytolacca latbenia. The phytotoxic effects were checked at 10,000, 1000, and 100 µg/ml against two economically important standard target species, Triticum aestivum (monocot representative) and Brassica napus (dicot representative). The phytotoxicity effects on seed germination, seedling growth and seedling weight were checked. A simple, cost-effective in vitro phytotoxicity assay (that uses petri plates) was used to evaluate the allelopathic properties of crude extracts. At highest concentration, extracts from all the three plants showed phytotoxic activities such that P. latbenia > E. wallichii > B. ciliata. In seedling growth, root length was affected more than shoot length, whereas among the target species B. napus was found to be more sensitive towards extracts when compared with T. aestivum. Phytochemical analysis showed that P. latbenia is rich in saponins and terpenoids, while E. wallichii and B. ciliata are rich in tannins, terpenoids and cardiac glycoside. P. latbenia also carries a moderate amount of cardiac glycosides. © The Author(s) 2012.

  6. Phytotoxicity Study on Bidens sulphurea Sch. Bip. as a Preliminary Approach for Weed Control.

    Science.gov (United States)

    da Silva, Bruna P; Nepomuceno, Mariluce P; Varela, Rosa M; Torres, Ascensión; Molinillo, José M G; Alves, Pedro L C A; Macías, Francisco A

    2017-06-28

    Farmers of the Franca region in Brazil observed that Bidens sulphurea was able to eliminate the Panicum maximum weed, which infected coffee plantations, without affecting the crop. In an effort to determine if the inhibitory effects observed were due to the presence of phytotoxic compounds from leaves and roots, a biodirected isolation and spectroscopic characterization has been carried out. The leaf dichloromethane and root acetone extracts were the most active, and the former appeared to be more phytotoxic to the target species, including four weeds. A total of 26 compounds were isolated from leaves and roots, and four of them are described here for the first time. The major compounds in the leaf extract are the sesquiterpene lactones costunolide, reynosin, and santamarine, and these showed marked inhibition. Amaranthus viridis and Panicum maximum were the most sensitive species of the weeds tested. These three phytotoxic lactones were also evaluated on A. viridis and P. maximum under hydroponic conditions. A. viridis was the most affected species with the three lactones, and santamarine was the most phytotoxic compound on both. This is the first time that the phytotoxicity of sesquiterpene lactones has been evaluated on hydroponic culture. The work described here is a preliminary approach for the use of B. sulphurea for weed control in agriculture, both as a cover crop and by use of its components as natural herbicide leads.

  7. Assessing Executive Functioning: A Pragmatic Review

    Science.gov (United States)

    Hass, Michael R.; Patterson, Ashlea; Sukraw, Jocelyn; Sullivan, Brianna M.

    2014-01-01

    Despite the common usage of the term "executive functioning" in neuropsychology, several aspects of this concept remain unsettled. In this paper, we will address some of the issues surrounding the notion of executive functioning and how an understanding of executive functioning and its components might assist school-based practitioners…

  8. Executive summary

    International Nuclear Information System (INIS)

    2002-01-01

    On 18 May 2001, the Finnish Parliament ratified the Decision in Principle on the final disposal facility for spent nuclear fuel at Olkiluoto, within the municipality of Eurajoki. The Municipality Council and the government has made positive decisions earlier, at the end of 2000, and in compliance with the Nuclear Energy Act, Parliament's ratification was then required. The decision is valid for the spent fuel generated by the existing Finnish nuclear power plants and means that the construction of the final disposal facility is considered to be in line with the overall good of society. Earlier steps included, amongst others, the approval of the technical project by the Safety Authority. Future steps include construction of an underground rock characterisation facility, ONKALO (2003-2004), and application for separate construction and operating licences for the final disposal facility (from about 2010). How did this political and societal decision come about? The FSC Workshop provided the opportunity to present the history leading up to the Decision in Principle (DiP), and to examine future perspectives with an emphasis on stakeholder involvement. This Executive Summary gives an overview of the presentations and discussions that took place at the workshop. It presents, for the most part, a factual account of the individual presentations and of the discussions that took place. It relies importantly on the notes that were taken at the meeting. Most materials are elaborated upon in a fuller way in the texts that the various speakers and session moderators contributed for these proceedings. The structure of the Executive Summary follows the structure of the workshop itself. Complementary to this Summary and also provided with this document, is a NEA Secretariat's perspective aiming to place the results of all discussions, feedback and site visit into an international perspective. (authors)

  9. Phytotoxic Effects of Lanthanum Oxide Nanoparticles on Maize (Zea mays L.)

    Science.gov (United States)

    Liu, Yinglin; Xu, Lina; Dai, Yanhui

    2018-02-01

    The use of lanthanum oxide nanoparticles (La2O3 NPs) in life products have increased dramatically in the past decades, which are inevitable released into natural environment. In this study, we determined the phytotoxicity of La2O3 NPs to maize (Zea mays L.) grown in one-fourth strength Hoagland solution. After being exposed for two weeks, the biomass, roots length and the relative chlorophyll content were measured. La2O3 NPs had phytotoxicity to maize at 5 mg/L. La2O3 NPs decreased shoot biomass (≥10 mg/L), the root biomass and length (≥5 mg/L). Moreover, La2O3 NPs had adverse effects on the chlorophyll content (≥10 mg/L). The decreased chlorophyll content may reduce net photosynthetic rate. This research offers vital information about the phytotoxicity of La2O3 NPs.

  10. Lipid peroxidation: A phytotoxic consequence of air pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Kunert, K J; Mehlhorn, H; Schmidt, A; Horsch, F; Filby, G; Fund, N; Gross, S; Hanisch, B; Kilz, E; Seidel, A [comps.

    1986-04-01

    Spruce and fir, both 10 years of age, were exposed to purified air, ozone (0.14 mg/m/sup 3/ air), SO/sub 2/ (0.03 mg/m/sup 3/ air), or a combination of both gases in open top chambers. With age, a combination of both gases significantly increased the content of the antioxidants vitamin E and C and glutathione in needles of fir and spruce when compared to the control treated with purified air. The increase was stronger in needles of fir than in needles of spruce. Further, the increase was already found in the youngest needles of fir. Compared to the control, no significant higher amount of antioxidants was observed when trees were exposed to ozone alone. Moreover, ozone exposure was less effective than SO/sub 2/ exposure. Combination of both air pollutants induced synergistic effects. In field studies (location: Schwarzwald, Kaelbelescheuer/Haldenhof), needles of spruce also showed an increase in the vitamin E content dependent on the extent of damage. This increase was partly accompanied by a higher amount of vitamin C and an increased degree of lipid peroxidation, measured as ethane production. Our results from open top experiments are consistent with our previous data investigating natural aging in higher plants. Therefore we suggest that by the phytotoxic action of air pollutants, such as SO/sub 2/ and SO/sub 2/ + ozone, age-related peroxidative processes are accelerated. Further, both vitamin E and glutathione are specific indicators of these processes. By now, no direct and significant correlation between field studies and studies with open tops has been found.

  11. Pore-water chemistry explains zinc phytotoxicity in soil.

    Science.gov (United States)

    Kader, Mohammed; Lamb, Dane T; Correll, Ray; Megharaj, Mallavarapu; Naidu, Ravi

    2015-12-01

    Zinc (Zn) is a widespread soil contaminant arising from a numerous anthropogenic sources. However, adequately predicting toxicity of Zn to ecological receptors remains difficult due to the complexity of soil characteristics. In this study, we examined solid-solution partitioning using pore-water data and toxicity of Zn to cucumber (Cucumis sativus L.) in spiked soils. Pore-water effective concentration (ECx, x=10%, 20% and 50% reduction) values were negatively related to pH, indicating lower Zn pore water concentration were needed to cause phytotoxicity at high pH soils. Total dissolved zinc (Znpw) and free zinc (Zn(2+)) in soil-pore water successfully described 78% and 80.3% of the variation in relative growth (%) in the full dataset. When the complete data set was used (10 soils), the estimated EC50pw was 450 and 79.2 µM for Znpw and Zn(2+), respectively. Total added Zn, soil pore water pH (pHpw) and dissolve organic carbon (DOC) were the best predictors of Znpw and Zn(2+) in pore-water. The EC10 (total loading) values ranged from 179 to 5214 mg/kg, depending on soil type. Only pH measurements in soil were related to ECx total Zn data. The strongest relationship to ECx overall was pHca, although pHw and pHpw were in general related to Zn ECx. Similarly, when a solution-only model was used to predict Zn in shoot, DOC was negatively related to Zn in shoot, indicating a reduction in uptake/ translocation of Zn from solution with increasing DOC. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Essential Oil Constituents of Tanacetum cilicicum: Antimicrobial and Phytotoxic Activities

    Directory of Open Access Journals (Sweden)

    Zeynep Ulukanli

    2017-01-01

    Full Text Available Aerial parts of Tanacetum cilicicum were hydrodistillated for 3 h using Clevenger. Essential oil (EO yield was 0.4% (v/w. According to the GC/MS analyses, EO of T. cilicicum consisted of monoterpenes [α-pinene (2.95 ± 0.19%, sabinene (2.32 ± 0.11%, and limonene (3.17 ± 0.25], oxygenated monoterpenes [eucalyptol (5.08 ± 0.32%, camphor (3.53 ± 0.27%, linalool (7.01 ± 0.32%, α-terpineol (3.13 ± 0.23%, and borneol (4.21 ± 0.17%], and sesquiterpenes [sesquisabinene hydrate (6.88 ± 0.41%, nerolidol (4.90 ± 0.33%, α-muurolol (4.57%  ± 0.35, spathulanol (2.98 ± 0.12%, juniper camphor (2.68 ± 0.19%, (--caryophyllene oxide (2.64 ± 0.19%, 8-hydroxylinalool (2.62 ± 0.15%, and Δ-cadinene (2.48 ± 0.16%]. In the antimicrobial assay, MIC/MBC values of the EO were the most significant on B. subtilis (0.39/0.78 µL/mL and B. cereus (0.78/1.56 µL/mL. The most prominent phytotoxic activities of the EO were observed on L. sativa, L. sativum, and P. oleracea. The results of the present study indicated that EO of T. cilicicum includes various medicinally and industrially crucial phytoconstituents that could be in use for industrial applications. The finding of this study is the first report on this species from the East Mediterranean region.

  13. Phytotoxic activity of bibenzyl derivatives from the orchid Epidendrum rigidum.

    Science.gov (United States)

    Hernández-Romero, Yanet; Acevedo, Laura; Sánchez, María de los Angeles; Shier, W Thomas; Abbas, Hamed K; Mata, Rachel

    2005-08-10

    A whole plant chloroform-methanol extract of the orchid Epidendrum rigidum inhibited radicle growth of Amaranthus hypochondriacus seedlings (IC50 = 300 microg/mL). Bioassay-guided fractionation furnished four phytotoxins, namely, gigantol (1), batatasin III (2), 2,3-dimethoxy-9,10-dihydrophenathrene-4,7-diol (9), and 3,4,9-trimethoxyphenanthrene-2,5-diol (11), along with the known flavonoids apigenin, vitexin, and isovetin and the triterterpenoids 24,24-dimethyl-9,19-cyclolanostane-25-en-3beta-ol (14) and 24-methyl-9,19-cyclolanostane-25-en-3beta-ol (15). Stilbenoids 1, 2, 9, and 11 inhibited radicle growth of A. hypochondriacus with IC50 values of 0.65, 0.1, 0.12, and 5.9 microM, respectively. Foliar application of gigantol (1) at 1 microM to 4 week old seedlings of A. hypochondriacus reduced shoot elongation by 69% and fresh weight accumulation by 54%. Bibenzyls 1 and 2, as well as synthetic analogues 4'-hydroxy-3,3',5-trimethoxybibenzyl (3), 3,3',4',5-tetramethoxybibenzyl (4), 3,4'-dihydroxy-5-methoxybibenzyl (5), 3'-O-methylbatatasin III (6), 3,3',5-trihydroxybibenzyl (7), and 3,4',5-trihydroxybibenzyl (8), were tested for phytotoxicity in axenic cultures of the small aquatic plant Lemna pausicostata. All bibenzyls derivatives except 7 and 8 inhibited growth and increased cellular leakage with IC50 values of 89.9-180 and 89.9-166 microM, respectively. The natural and synthetic bibenzyls showed marginal cytotoxicity on animal cells. The results suggest that orchid bibenzyls may be good lead compounds for the development of novel herbicidal agents.

  14. Acute phytotoxicity of seven metals alone and in mixture: Are Italian soil threshold concentrations suitable for plant protection?

    International Nuclear Information System (INIS)

    Baderna, Diego; Lomazzi, Eleonora; Pogliaghi, Alberto; Ciaccia, Gianluca; Lodi, Marco; Benfenati, Emilio

    2015-01-01

    Metals can pollute soils in both urban and rural areas with severe impacts on the health of humans, plants and animals living there. Information on metal toxicity is therefore important for ecotoxicology. This study investigated the phytotoxicity of different metals frequently found as pollutants in soils: arsenic, cadmium, chromium, lead, mercury, nickel and zinc. Cucumber (Cucumis sativus), sorghum (Sorghum saccharatum) and cress (Lepidium sativum) seeds were used as models for other plants used in human nutrition such as cereals, rice, fruits and vegetables. The 72-h germination rate and root elongations were selected as short-term ecotoxicological endpoints in seeds exposed to single metals and mixtures. Metals were spiked onto OECD standard soils in concentrations comparable to current Italian contamination threshold concentrations for residential and commercial soils. Arsenic, chromium, mercury and nickel were the most toxic metals in our experimental conditions, particularly to cress seeds (5.172, 152 and 255.4 mg/kg as 72 h IC50 for arsenic, mercury and nickel respectively). Italian limits were acceptable for plant protection only for exposure to each metal alone but not for the mixtures containing all the metals concentrations expected by their respective legislative threshold. The effects of the mixture were class-specific: trends were comparable in dicots but different in monocots. The response induced by the mixture at high concentrations differed from that theoretically obtainable by summing the effects of the individual metals. This might be due to partial antagonism of the metals in soil or to the formation of complexes between the metals, which reduce the bioavailability of the pollutants for plants. - Graphical abstract: Metals investigated: Arsenic, Cadmium, Chromium, Lead, Mercury, Nickel and Zinc. - Highlights: • The short-term phytotoxicity of seven metals was investigated with 3 higher plants. • Italian limits for arsenic and nickel in

  15. Phytotoxicity of trace metals in spiked and field-contaminated soils: Linking soil-extractable metals with toxicity.

    Science.gov (United States)

    Hamels, Fanny; Malevé, Jasmina; Sonnet, Philippe; Kleja, Dan Berggren; Smolders, Erik

    2014-11-01

    Soil tests have been widely developed to predict trace metal uptake by plants. The prediction of metal toxicity, however, has rarely been tested. The present study was set up to compare 8 established soil tests for diagnosing phytotoxicity in contaminated soils. Nine soils contaminated with Zn or Cu by metal mining, smelting, or processing were collected. Uncontaminated reference soils with similar soil properties were sampled, and series of increasing contamination were created by mixing each with the corresponding soil. In addition, each reference soil was spiked with either ZnCl2 or CuCl2 at several concentrations. Total metal toxicity to barley seedling growth in the field-contaminated soils was up to 30 times lower than that in corresponding spiked soils. Total metal (aqua regia-soluble) toxicity thresholds of 50% effective concentrations (EC50) varied by factors up to 260 (Zn) or 6 (Cu) among soils. For Zn, variations in EC50 thresholds decreased as aqua regia > 0.43 M HNO3  > 0.05 M ethylenediamine tetraacetic acid (EDTA) > 1 M NH4 NO3  > cobaltihexamine > diffusive gradients in thin films (DGT) > 0.001 M CaCl2 , suggesting that the last extraction is the most robust phytotoxicity index for Zn. The EDTA extraction was the most robust for Cu-contaminated soils. The isotopically exchangeable fraction of the total soil metal in the field-contaminated soils markedly explained the lower toxicity compared with spiked soils. The isotope exchange method can be used to translate soil metal limits derived from soils spiked with metal salts to site-specific soil metal limits. © 2014 SETAC.

  16. Acute phytotoxicity of seven metals alone and in mixture: Are Italian soil threshold concentrations suitable for plant protection?

    Energy Technology Data Exchange (ETDEWEB)

    Baderna, Diego, E-mail: diego.baderna@marionegri.it; Lomazzi, Eleonora; Pogliaghi, Alberto; Ciaccia, Gianluca; Lodi, Marco; Benfenati, Emilio

    2015-07-15

    Metals can pollute soils in both urban and rural areas with severe impacts on the health of humans, plants and animals living there. Information on metal toxicity is therefore important for ecotoxicology. This study investigated the phytotoxicity of different metals frequently found as pollutants in soils: arsenic, cadmium, chromium, lead, mercury, nickel and zinc. Cucumber (Cucumis sativus), sorghum (Sorghum saccharatum) and cress (Lepidium sativum) seeds were used as models for other plants used in human nutrition such as cereals, rice, fruits and vegetables. The 72-h germination rate and root elongations were selected as short-term ecotoxicological endpoints in seeds exposed to single metals and mixtures. Metals were spiked onto OECD standard soils in concentrations comparable to current Italian contamination threshold concentrations for residential and commercial soils. Arsenic, chromium, mercury and nickel were the most toxic metals in our experimental conditions, particularly to cress seeds (5.172, 152 and 255.4 mg/kg as 72 h IC50 for arsenic, mercury and nickel respectively). Italian limits were acceptable for plant protection only for exposure to each metal alone but not for the mixtures containing all the metals concentrations expected by their respective legislative threshold. The effects of the mixture were class-specific: trends were comparable in dicots but different in monocots. The response induced by the mixture at high concentrations differed from that theoretically obtainable by summing the effects of the individual metals. This might be due to partial antagonism of the metals in soil or to the formation of complexes between the metals, which reduce the bioavailability of the pollutants for plants. - Graphical abstract: Metals investigated: Arsenic, Cadmium, Chromium, Lead, Mercury, Nickel and Zinc. - Highlights: • The short-term phytotoxicity of seven metals was investigated with 3 higher plants. • Italian limits for arsenic and nickel in

  17. Arsenic-contaminated soils. Phytotoxicity studies with sunflower and sorghum

    Energy Technology Data Exchange (ETDEWEB)

    Lyubun, Y.V.; Kosterin, P.V.; Zakharova, E.A.; Fedorov, E.E. [Inst. of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, Saratov (Russian Federation); Shcherbakov, A.A. [Saratov Military Inst. of Radiological, Chemical and Biological Defence, Saratov (Russian Federation)

    2002-07-01

    Background, Aim and Scope. Environmental pollution caused by arsenic (As) is a major ecological problem. There has been intense worldwide effort to find As-hyperaccumulating plants that can be used in phytoremediation - the green-plant-assisted removal of chemical pollutants from soils. For phytoremediation, it is natural to prefer cultivated rather than wild plants, because their agriculture is well known. This study was conducted to evaluate the tolerance of common sunflower (Helianthus annuus L.) and sugar sorghum (Sorghum saccharatum Pers.) for soil-As contents of 10-100 mg As kg{sup -1} soil, with sodium arsenite as a model contaminant. Methods. Plants were grown in a growth chamber for 30 days. Microfield experiments were conducted on experimental plots. To study the phytoremediation effect of the auxins indole-3-acetic acid (IAA) and 2,4-dichlorophenoxyacetic acid (2,4-D), we treated 1- and 3-day-old plant seedlings with water solutions of the auxins (concentrations of 10{sup -5}, 10{sup -7}, and 10{sup -9} g l{sup -1}). The soil and plant-biomass samples were analyzed for total As by using the color reaction of ammonium molybdate with As. Results and Discussion. Phytotoxicity studies showed that 100 mg as kg{sup -1} soil poisoned sunflower and sorghum growth by 50%. There was a linear correlation between soil-As content and As accumulation in the plants. Laboratory experiments showed that the soil-As content was reduced two- to threefold after sunflower had been grown with 10-100 mg As kg{sup -1} soil for 30 days. Treatment of sunflower and sorghum seedlings with IAA and 2,4-D at a concentration of 10{sup -5} g l{sup -1} in microfield experiments enhanced the phytoremediation two- to fivefold as compared with untreated control plants. The best results were obtained with 3-day-old seedlings. Conclusion, Recommendation and Outlook. (a) Sunflower and sorghum are good candidates to remediate As-polluted soils. (b) Phytoremediation can be improved with IAA or 2

  18. Prevalence and severity of gingivitis in school students aged 6-11 years in Tafelah Governorate, South Jordan: results of the survey executed by National Woman's Health Care Center.

    Science.gov (United States)

    Rodan, Rania; Khlaifat, Feryal; Smadi, Leena; Azab, Reem; Abdalmohdi, Asma

    2015-11-09

    A cross-sectional census was conducted on 994 public school students aged 6-11 years living in 3 different parts of Tafeleh Governorate-South of Jordan, to determine the prevalence, and severity of gingivitis and to evaluate the oral hygiene habits among them as a part a survey executed by National Woman's Health Care Center. All students were examined for gingival index (GI) and plaque index (PI), information about oral hygiene habits was recorded. Only 29.8 % had healthy gingiva, 38.5 % had mild gingivitis, 31.4 % had moderate gingivitis, and 0.3 % had severe gingivitis. The difference between both genders was not statistically significant P > 0.05. 36.8 % of the examined students never brushed their teeth. Average gingival index (GI) and average plaque index (PI) were 0.77 and 0.61 respectively. Fair oral hygiene with mild to moderate gingivitis is highly prevalent among Tafelah school children. This study indicated that oral health status among schoolchildren in Tafelah is poor and needs to be improved. Long-term school based oral health education programme is highly recommended.

  19. PHYTOTOXIC POTENTIAL OF THE GEOPROPOLIS EXTRACTS OF THE JANDAIRA STINGLESS BEE (Melipona subnitida IN WEEDS

    Directory of Open Access Journals (Sweden)

    DANIEL SANTIAGO PEREIRA

    2017-01-01

    Full Text Available The objective of the present research is to characterize the phytotoxic activity of geopropolis from the Jandaira bee (Melipona subnitida Ducke in the state of Ceará in Northeast Brazil and to analyze its effects. Extracts were prepared in 80% v/v grain alcohol at 0.25, 0.5, 0.75, and 1.0%. Their effects were determined on seed germination, radicle elongation, and hypocotyl growth of the pasture weeds malícia (Mimosa pudica and mata-pasto (Senna obtusifolia. Extract phytotoxicity varied as functions of plant species, application dosage, and plant organ. M. pudica was more sensitive to the inhibitory effects of geopropolis than S. obtusifolia. There was a phytotoxic effect of 50% (PE50 for S. obtusifolia in terms of seed germination and in rootlet development near the maximum applied concentrations. M. pudica had PE50 and PE90 at the minimum concentration (0.25% and near the maximum (1.00%, respectively. Thus, geopropolis extracts from the Jandaira bee (M. subnitida are potentially phytotoxic to certain plant species.

  20. Phytotoxic activity of crude aqueous extracts and fractions of young leaves of Sapindus saponaria L. (Sapindaceae

    Directory of Open Access Journals (Sweden)

    Patrícia Umeda Grisi

    2013-03-01

    Full Text Available The aim of this study was to evaluate the phytotoxic potential of aqueous extract of young leaves of Sapindus saponaria L. (soapberry on the diaspore germination and seedling growth Lactuca sativa L. (lettuce and Allium cepa L. (onion, as well as to determine, by bioassay-guided fractioning, whether the fractionated extracts of those leaves are phytotoxic to Triticum aestivum L. (wheat coleoptiles. The aqueous extract was prepared using 100 g of dried plant material dissolved in 1000 ml of distilled water, resulting in a concentration of 10.0%. Distilled water was added in order to obtain dilutions of 7.5%, 5.0%, and 2.5%. The extraction was carried out with young leaves (in powder form and organic solvents of various polarities. We fractioned the ethyl acetate extract using column chromatography. The phytotoxic potential of the aqueous extract of young leaves S. saponaria varied according to the receiving species and the concentration-dependent inhibitory effect. The ethyl acetate extract, specifically fraction 6 (57-70, had the greatest inhibitory effect on the elongation of wheat coleoptiles, indicating that the compounds responsible for the phytotoxic effect reside within this fraction.

  1. Phytotoxicity of Sodium Fluoride and Uptake of Fluoride in Willow Trees

    DEFF Research Database (Denmark)

    Clausen, Lauge Peter Westergaard; Gosewinkel Karlson, Ulrich; Trapp, Stefan

    2015-01-01

    The willow tree (Salix viminalis) toxicity test and a cress seed germination test (Lepidium sativum) were used to determine uptake and phytotoxicity of NaF. Concentrations in hydroponic solutions were 0-1000 mg F/L and 0-400 mg F/L in the preliminary and definitive test. A third test was done...

  2. Influence of amino acids on the phytotoxicity of 2-benzoxazolinone on Lemna paucicostata

    Science.gov (United States)

    2-Benzoxazolinone (BOA) is a phytotoxic compound that induces strong effects on plant metabolism. BOA effects include increased membrane permeability, degradation of proteins and pigments, increased lipid peroxidation, oxidative stress and senescence induction. In this work, the effects of amino aci...

  3. Phytotoxicity data safeguard the performance of the recipient plants in leachate irrigation

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, C.Y. [Department of Biology, Chinese University of Hong Kong, Shatin, N.T., Hong Kong (China); Chu, L.M. [Department of Biology, Chinese University of Hong Kong, Shatin, N.T., Hong Kong (China)]. E-mail: leemanchu@cuhk.edu.hk

    2007-01-15

    Leachates from an operating and a closed landfill were examined for their phytotoxicity by seed germination/root elongation tests using seeds of Brassica chinensis and Lolium perenne. Their EC50s ranged from 3% to 46% v/v, which varied remarkably with the operating status of the landfills. Seedlings of twelve tree species were grown in pots, which were irrigated with landfill leachate at the EC50 levels, with tap water as control. No tree mortality or growth inhibition was observed after 90 days of leachate application. Chlorophyll fluorescence measurement also showed that plants receiving leachate did not suffer from a decline in photosynthetic efficiency. Litsea glutinosa and Hibiscus tiliaceus had remarkable growth, and other non-N-fixers were not inferior to the N-fixing Acacia auriculiformis. Leachate irrigation improved soil N content, though P deficiency is still a problem. The seed bioassay provided a conservative estimate of the phytotoxicity of landfill leachate. Plants irrigated can be protected from growth inhibition when the leachate irrigation plan is designed with reference to phytotoxicity data. - Irrigated plants could be benefited by leachate when the application rate was determined according to phytotoxicity data.

  4. Phytotoxicity data safeguard the performance of the recipient plants in leachate irrigation

    International Nuclear Information System (INIS)

    Cheng, C.Y.; Chu, L.M.

    2007-01-01

    Leachates from an operating and a closed landfill were examined for their phytotoxicity by seed germination/root elongation tests using seeds of Brassica chinensis and Lolium perenne. Their EC50s ranged from 3% to 46% v/v, which varied remarkably with the operating status of the landfills. Seedlings of twelve tree species were grown in pots, which were irrigated with landfill leachate at the EC50 levels, with tap water as control. No tree mortality or growth inhibition was observed after 90 days of leachate application. Chlorophyll fluorescence measurement also showed that plants receiving leachate did not suffer from a decline in photosynthetic efficiency. Litsea glutinosa and Hibiscus tiliaceus had remarkable growth, and other non-N-fixers were not inferior to the N-fixing Acacia auriculiformis. Leachate irrigation improved soil N content, though P deficiency is still a problem. The seed bioassay provided a conservative estimate of the phytotoxicity of landfill leachate. Plants irrigated can be protected from growth inhibition when the leachate irrigation plan is designed with reference to phytotoxicity data. - Irrigated plants could be benefited by leachate when the application rate was determined according to phytotoxicity data

  5. Novel Alleviation Mechanisms of Aluminum Phytotoxicity via Released Biosilicon from Rice Straw-Derived Biochars

    Science.gov (United States)

    Qian, Linbo; Chen, Baoliang; Chen, Mengfang

    2016-07-01

    Replacing biosilicon and biocarbon in soil via biochar amendment is a novel approach for soil amelioration and pollution remediation. The unique roles of silicon (Si)-rich biochar in aluminum (Al) phytotoxicity alleviation have not been discovered. In this study, the alleviation of Al phytotoxicity to wheat plants (root tips cell death) by biochars fabricated from rice straw pyrolyzed at 400 and 700 °C (RS400 and RS700) and the feedstock (RS100) were studied using a slurry system containing typical acidic soils for a 15-day exposure experiment. The distributions of Al and Si in the slurry solution, soil and plant root tissue were monitored by staining methods, chemical extractions and SEM-EDS observations. We found that the biological sourced silicon in biochars served dual roles in Al phytotoxicity alleviation in acidic soil slurry. On one hand, the Si particles reduced the amount of soil exchangeable Al and prevented the migration of Al to the plant. More importantly, the Si released from biochars synchronously absorbed by the plants and coordinated with Al to form Al-Si compounds in the epidermis of wheat roots, which is a new mechanism for Al phytotoxicity alleviation in acidic soil slurry by biochar amendment. In addition, the steady release of Si from the rice straw-derived biochars was a sustainable Si source for aluminosilicate reconstruction in acidic soil.

  6. Pyrenophoric acids B and C, two new phytotoxic sesquiterpenoids produced by Pyrenophora semeniperda

    Science.gov (United States)

    Marco Masi; Susan Meyer; Alessio Cimmino; Suzette Clement; Beth Black; Antonio Evidente

    2014-01-01

    Two new phytotoxic sesquiterpenoid acids, named pyrenophoric acids B and C, were isolated together with the related pyrenophoric and abscisic acids from solid Bromus tectorum (cheatgrass) seed culture of the seed pathogen Pyrenophora semeniperda. This fungus has been proposed as a mycoherbicide for biocontrol of cheatgrass (Bromus tectorum), a Eurasian annual grass...

  7. Phytotoxicity of acyclic nucleoside phosphonates in Brassica pekinensis and Solanum lycopersicum

    Czech Academy of Sciences Publication Activity Database

    Špak, Josef; Janeba, Zlatko; Jansa, Petr; Baszczyňski, Ondřej; Pavingerová, Daniela; Špaková, Vlastimila

    2016-01-01

    Roč. 125, č. 2 (2016), s. 375-379 ISSN 0167-6857 Institutional support: RVO:60077344 ; RVO:61388963 Keywords : Chemotherapy * Virus eradication * Phytotoxicity Subject RIV: EE - Microbiology, Virology; CC - Organic Chemistry (UOCHB-X) Impact factor: 2.002, year: 2016

  8. Phytotoxicity of effluents from swine slaughterhouses using lettuce and cucumber seeds as bioindicators.

    Science.gov (United States)

    Gerber, Michel David; Lucia, Thomaz; Correa, Luciara; Neto, José Eduardo Pereira; Correa, Érico Kunde

    2017-08-15

    This study evaluated the phytotoxic effects of raw and treated effluents from a swine slaughterhouse on cucumber and lettuce seeds and determined correlations among physicochemical characteristics of such effluents and the germination of seeds used as bioindicators. Physicochemical parameters were characterized for both effluents and their phytotoxicity was determined through the germination index (GI), the root length (RL) and the number of germinated seeds (SG) for both plant species. The effluents treatment system was efficient to reduce the concentration of some physicochemical parameters to levels within those recommended by the Brazilian legislation, except for P, ammoniacal N and TKN concentration. Although phytotoxicity of the treated effluent was less in comparison to the raw effluent, the GI for cucumber and lettuce seeds submitted to each of the tested effluents was lower than 80%. Thus, both effluents were phytotoxic for the tested bioindicators (peffluent. The Zn concentration in the treated effluent showed a negative correlation (peffluents from swine slaughterhouses may impair the germination of the evaluated plant species if used for agricultural purposes. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Phytotoxicity and Benzoxazinone Concentration in Field Grown Cereal Rye (Secale cereale L.

    Directory of Open Access Journals (Sweden)

    C. La Hovary

    2016-01-01

    Full Text Available Winter rye (Secale cereale L. is used as a cover crop because of the weed suppression potential of its mulch. To gain insight into the more effective use of rye as a cover crop we assessed changes in benzoxazinone (BX levels in rye shoot tissue over the growing season. Four rye varieties were planted in the fall and samples harvested at intervals the following spring. Two different measures of phytotoxic compound content were taken. Seed germination bioassays were used as an estimate of total phytotoxic potential. Dilutions of shoot extracts were tested using two indicator species to compare the relative toxicity of tissue. In addition, BX (DIBOA, DIBOA-glycoside, and BOA levels were directly determined using gas chromatography. Results showed that rye tissue harvested in March was the most toxic to indicator species, with toxicity decreasing thereafter. Likewise the BX concentration in rye shoot tissue increased early in the season and then decreased over time. Thus, phytotoxicity measured by bioassay and BX levels measured by GC have a similar but not identical temporal profile. The observed decrease in phytotoxic potential and plant BX levels in rye later in the season appears to correlate with the transition from vegetative to reproductive growth.

  10. Phytotoxic potential of young leaves from Blepharocalyx salicifolius (Kunth O. Berg (Myrtaceae

    Directory of Open Access Journals (Sweden)

    E. Habermann

    Full Text Available Abstract The loss of leaves by plant species found in the Cerrado (Brazilian savanna is an energetically expensive process due to adverse environmental conditions and predation by herbivory. The mature leaves have adaptations which minimize these events. However, the young individuals lack these structures and produce high leaf concentrations of secondary metabolites as a form of protection. These compounds can be used in bioprospection of natural herbicides. Thus, this study aimed to evaluate the phytotoxicity of hexane, ethyl acetate and aqueous extracts of young leaves from Blepharocalyx salicifolius (Kunth O. Berg on the elongation of wheat coleoptiles (Triticum aestivum L. and evaluate the potential phytotoxic of ethyl acetate extract on germination, growth and cell size of metaxylem of sesame (Sesamum indicum L. seedlings. The hexane and ethyl acetate extracts inhibited the elongation of wheat coleoptiles at all concentrations; however, the most promising results were observed in coleoptile fragments treated with the ethyl acetate extract. This treatment changed the mean germination time and the synchrony of sesame seeds, inhibited the growth of shoots and roots, reduced the dry weight of seedlings, led to abnormalities in the seedlings and reduced the length of the metaxylem cells in the sesame seedlings. These results demonstrated the phytotoxic potential of young leaf extracts of B. salicifolius and the high phytotoxicity of the ethyl acetate extract in the initial development of S. indicum.

  11. Residues of bioenergy production chains as soil amendments: Immediate and temporal phytotoxicity

    NARCIS (Netherlands)

    Gell, K.; Groenigen, van J.W.; Cayuela, M.L.

    2011-01-01

    The current shift towards bioenergy production increases streams of bioenergy rest-products (RPs), which are likely to end-up as soil amendments. However, their impact on soil remains unclear. In this study we evaluated crop phytotoxicity of 15 RPs from common bioenergy chains (biogas, biodiesel,

  12. Phytotoxicity and uptake of nanoscale zero-valent iron (nZVI) by two plant species

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xingmao, E-mail: ma@engr.siu.edu [Civil and Environmental Engineering, Southern Illinois University Carbondale, IL 62901 (United States); Gurung, Arun [Civil and Environmental Engineering, Southern Illinois University Carbondale, IL 62901 (United States); Deng, Yang [Earth and Environmental Studies, Montclair State University, NJ 07403 (United States)

    2013-01-15

    Use of nano-scale zero valent iron (nZVI) for the treatment of various environmental pollutants has been proven successful. However, large scale introduction of engineered nanomaterials such as nZVI into the environment has recently attracted serious concerns. There is an urgent need to investigate the environmental fate and impact of nZVI due to the scope of its application. The goal of this study was to evaluate the toxicity and accumulation of bare nZVI by two commonly encountered plant species: cattail (Typha latifolia) and hybrid poplars (Populous deltoids × Populous nigra). Plant seedlings were grown hydroponically in a greenhouse and dosed with different concentrations of nZVI (0–1000 mg/L) for four weeks. The nZVI exhibited strong toxic effect on Typha at higher concentrations (> 200 mg/L) but enhanced plant growth at lower concentrations. nZVI also significantly reduced the transpiration and growth of hybrid poplars at higher concentrations. Microscopic images indicated that large amount of nZVI coated on plant root surface as irregular aggregates and some nZVI penetrated into several layers of epidermal cells. Transmission electron microscope (TEM) and scanning transmission electron microscope (STEM) confirmed the internalization of nZVI by poplar root cells but similar internalization was not observed for Typha root cells. The upward transport to shoots was minimal for both plant species. - Highlights: ► nZVI may exert phytotoxic effects on plants at concentrations (> 200 mg/L) often encountered in site remediation practices. ► nZVI deposits on plant root surface as aggregates and some could internalize in plant root cells. ► Plant uptake and accumulation of nZVI are plant species-dependent. ► Upward transport from roots to shoots was not observed.

  13. Phytotoxicity of veterinary antibiotics to seed germination and root elongation of crops.

    Science.gov (United States)

    Pan, Min; Chu, L M

    2016-04-01

    Large quantities of veterinary antibiotics (VAs) are being used worldwide in agricultural fields through wastewater irrigation and manure application. They cause damages to the ecosystem when discharged into the environment, but there is a lack of information on their toxicity to plants and animals. This study evaluated the phytotoxic effects of five major VAs, namely tetracycline (TC), sulfamethazine (SMZ), norfloxacin (NOR), erythromycin (ERY) and chloramphenicol (CAP), on seed germination and root elongation in lettuce, tomato, carrot and cucumber, and investigated the relationship between their physicochemical properties and phytotoxicities. Results show that these compounds significantly inhibited root elongation (ptest. TC was associated with the highest level of toxicity, followed by NOR, ERY, SMZ and CAP. Regarding crop species, lettuce was found to be sensitive to most of the VAs. The median effect concentration (EC50) of TC, SMZ, NOR, ERY and CAP to lettuce was 14.4, 157, 49.4, 68.8 and 204 mg/L, respectively. A quantitative structure-activity relationship (QSAR) model has been established based on the measured data. It is evident that hydrophobicity was the most important factor governing the phytotoxicity of these compounds to seeds, which could be explained by the polar narcosis mechanism. Lettuce is considered a good biomarker for VAs in the environment. According to the derived equation, phytotoxicities of selected VA compounds on different crops can be calculated, which could be applicable to other VAs. Environmental risks of VAs were summarized based on the phytotoxicity results and other persistent factors. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Phytotoxicity of Alachlor, Bromacil and Diuron as single or mixed herbicides applied to wheat, melon, and molokhia

    OpenAIRE

    El-Nahhal, Yasser; Hamdona, Nisreen

    2015-01-01

    This study investigated the phytotoxicity of herbicides applied singly or as mixtures to different crops under greenhouse conditions. Growth inhibition of the crops was taken as an indicator of phytotoxicity. Phytotoxicity of mixtures was estimated by calculating EC50 value in toxic units. EC50 (mg/kg soil) of Alachlor, Bromacil and/or Diuron were: 11.37, 4.77, 1.64, respectively, on melon; 0.11, 0.08, 0.24, respectively, on molokhia, and 3.91, 3.08, 1.83, respectively, on wheat. EC50 values ...

  15. Production of Phytotoxic Metabolite Using Biphasic Fermentation System from Strain C1136 of Lasiodiplodia pseudotheobromae, a Potential Bioherbicidal Agent

    Directory of Open Access Journals (Sweden)

    Charles Oluwaseun ADETUNJI

    2017-09-01

    Full Text Available Formulation of effective and environmental friendly bioherbicides depends on the type of fermentation medium used for the production of phytotoxic metabolites. The effect of biomass, colony forming unit and the phytotoxic metabolite produced from the biphasic fermentation was carried out, while the phytotoxic metabolite was tested in vivo and in-vitro on Echinochola crus-galli and dicotyledonous Chromolaena odorata. The mutant strain of Lasiodiplodia pseudotheobromae C1136 (Lp90 produced the highest amount of conidia and the largest necrotic area on the two tested weeds when compared to its wild strain in the different biphasic media combinations. The study revealed that the biphasic system containing PDB + rice produced the highest bioherbicidal activities. Therefore, the phytotoxic metabolites from strain C1136 are suggested for large scale production of bioherbicides for the management of weeds in conventional farming to improve yield and enhance food security.

  16. New phytotoxic diterpenoids from Vellozia gigantea (Velloziaceae), an endemic neotropical plant living in the endangered Brazilian biome Rupestrian grasslands

    Science.gov (United States)

    Vellozia gigantea is a rare, ancient and endemic neotropical plant present in the Brazilian Rupestrian grasslands. The dichloromethane extract of V. gigantea adventitious roots was phytotoxic against Lactuca sativa, Agrostis stolonifera and Lemna paucicostata, and showed larvicidal activity against ...

  17. ECOTOXICITY AND PHYTOTOXICITY OF PLANT PROTECTION PRODUCTS TO RHIZOSPHERE FUNGI AND WINTER WHEAT SEEDLINGS

    Directory of Open Access Journals (Sweden)

    Anna Daria Stasiulewicz-Paluch

    2015-11-01

    Full Text Available Registration of plant protection products involves the analysis of their effects on soil microorganisms. The residues of plant protection products penetrate the soil, but their impact on fungi remains scarcely researched. In this study, the influence of selected plant protection products on the abundance of rhizosphere-dwelling fungi and the growth of winter wheat seedlings was evaluated under greenhouse conditions. The analysed plant protection products had an inhibitory effect on the growth of filamentous fungi in the rhizosphere, whereas yeasts were resistant to those products applied to soil. Tebuconazole exerted the strongest suppressive effect on the growth of filamentous fungi, and propiconazole was characterized by the greatest phytotoxic activity against winter wheat seedlings. Azoxystrobin had the weakest ecotoxic and phytotoxic effects, and its application to soil usually led to a rapid increase in the counts of fungi of the genus Acremonium.

  18. Allelopathy of small everlasting (Antennaria microphylla) : Phytotoxicity to leafy spurge (Euphorbia esula) in tissue culture.

    Science.gov (United States)

    Hogan, M E; Manners, G D

    1990-03-01

    Media and media extracts from callus cultures of small everlasting (Antennaria microphylla) inhibited leafy spurge (Euphorbia esula L.) callus tissue and suspension culture growth (50 and 70% of control, respectively) and were phytotoxic in lettuce and leafy spurge root elongation bioassays (64 and 77% of control, respectively). Hydroquinone, a phytotoxic compound previously isolated from small everlasting, was also biosynthesized by callus and suspension cultures of this species. Exogenously supplied hydroquinone (0.5 mM) was toxic to leafy spurge suspension culture cells and was only partially biotransformed to its nontoxic water-soluble monoglucoside, arbutin, by these cells. This report confirms the chronic involvement of hydroquinone in the allelopathic interaction between small everlasting and leafy spurge.

  19. Stereoselective Phytotoxicity of HCH Mediated by Photosynthetic and Antioxidant Defense Systems in Arabidopsis thaliana

    OpenAIRE

    Zhang, Qiong; Zhou, Cong; Zhang, Quan; Qian, Haifeng; Liu, Weiping; Zhao, Meirong

    2013-01-01

    BACKGROUND: Hexachlorocyclohexane (HCH) has been used for plant protection and sanitation world-widely, and its isomers have been detected in water, soil, and air as well as in vegetation. As a sink for lipophilic pollutants, vegetation is very important for the degradation and fate of organic contamination; however, little was known about their phytotoxicity and mechanisms of toxic effect. In this study, the stereoselective phototoxicity of four isomers (α, β, γ, and δ) of HCHs mediated by i...

  20. The phytotoxic effects and biodegradability of stored rapeseed oil and rapeseed oil methyl ester

    Directory of Open Access Journals (Sweden)

    V. VAUHKONEN

    2008-12-01

    Full Text Available The aims of this study were to determine the phytotoxicity of stored rapeseed (Brassica rapa oil (RSO and rapeseed oil methyl ester (RME after "spill like" contamination on the growth of barley (Hordeum vulgare and the biodegradability of these substances in OECD 301F test conditions and in ground water. Rapeseed oil and rapeseed oil methyl ester were both stored for a period of time and their fuel characteristics (e.g. acid number had changed from those set by the fuel standards and are considered to have an effect on its biodegradation. The phytotoxicity was tested using two different types of barley cultivars: ‘Saana’ and ‘Vilde’. The phytotoxic effect on the barley varieties was determined, after the growth season, by measuring the total biomass growth and the mass of 1000 kernels taken from the tests plots. Also visual inspection was used to determine what the effects on the barley growth were. These measurements suggest that both RSO and RME have a negative impact on barley sprouts and therefore the total growth of the barley. RSO and RME both decreased the total amount of harvested phytomass. The weight of 1000 kernels increased with low concentrations of these contaminants and high contamination levels reduced the mass of the kernels. The results of these experiments suggest that the stored rapeseed oil and rapeseed oil methyl ester are both phytotoxic materials and therefore will cause substantial loss of vegetation in the case of a fuel spill. The RSO and RME biodegraded effectively in the measurement period of 28 days under OECD test conditions: the degree of biodegradation being over 60%. The biodegradation in the ground water was much slower: the degree of biodegradation being about 10% after 28 days.;

  1. Effect of Metal Oxides on Plant Germination: Phytotoxicity of Nanoparticles, Bulk Materials, and Metal Ions

    Czech Academy of Sciences Publication Activity Database

    Landa, Přemysl; Cyrusová, Tereza; Jeřábková, J.; Drábek, O.; Vaněk, Tomáš; Podlipná, Radka

    2016-01-01

    Roč. 227, č. 12 (2016), č. článku 448. ISSN 0049-6979 R&D Projects: GA MŠk(CZ) LD14100; GA MŠk LD14125 Institutional support: RVO:61389030 Keywords : zno nanoparticles * pseudokirchneriella-subcapitata * particle solubility * oxidative stress * root-growth * toxicity * aluminum * cuo * ph * cytotoxicity * Nanoparticles * Phytotoxicity * Accumulation * Germination * Sinapis alba Subject RIV: DJ - Water Pollution ; Quality Impact factor: 1.702, year: 2016

  2. Suitability of some growth characteristics to indicate phytotoxicity in pot experiments on maize test plants

    Energy Technology Data Exchange (ETDEWEB)

    Bujtas, K [Research Institute for Soil Science and Agricultural Chemistry (RISSAC) of the Hungarian Academy of Sciences, 1022 Budapest (Hungary)

    1994-11-01

    Assessment of phytotoxic conditions is often based on measuring the dry matter production of plants, although other growth characteristics may be more sensitive indicators of toxic circumstances. Purpose of this study was to evaluate the suitability of such variables as fresh weight, dry matter accumulation of shoots, longitudinal growth of leaves, and correlations between these variables for quantifying phytotoxicity caused by provocative rates of a lenacil-based herbicide. Impact of soil texture and soil pH on the manifestation of toxic symptoms were also investigated in a pot experiment on three soil types with maize (Zea mays L. cv. Carla) as test plant. Although the external circumstances were much different from field conditions, the observed differences in the phytotoxicity on the three soils were consistent with the application recommendations of the herbicide. High toxicities were observed on acidic sandy soil, and less on a similarly acidic soil of heavier texture. In contrast, slight stimulations were observed on chernozem soil at application rates lower than or corresponding to recommended field rates. Sum of the lengths of the leaves was a relatively sensitive indicator of bioactivity, showing cumulatively the effects observed for the individual leaves. Correlations between fresh weight/dry matter accumulation and fresh weight/sum of the lengths of leaves were shown to be linear over the application range, with slopes depending mostly on soil texture, and less so on soil pH. The results indicate that the suitability of the investigated variables for assessing phytotoxicity may be different on the different soil types. (author)

  3. Phytotoxic effects of (+/--catechin in vitro, in soil, and in the field.

    Directory of Open Access Journals (Sweden)

    Inderjit

    Full Text Available BACKGROUND: Exploring the residence time of allelochemicals released by plants into different soils, episodic exposure of plants to allelochemicals, and the effects of allelochemicals in the field has the potential to improve our understanding of interactions among plants. METHODOLOGY/PRINCIPAL FINDINGS: We conducted experiments in India and the USA to understand the dynamics of soil concentrations and phytotoxicity of (+/--catechin, an allelopathic compound exuded from the roots of Centaurea maculosa, to other plants in vitro and in soil. Experiments with single and pulsed applications into soil were conducted in the field. Experimental application of (+/--catechin to soils always resulted in concentrations that were far lower than the amounts added but within the range of reported natural soil concentrations. Pulses replenished (+/--catechin levels in soils, but consistently at concentrations much lower than were applied, and even pulsed concentrations declined rapidly. Different natural soils varied substantially in the retention of (+/--catechin after application but consistent rapid decreases in concentrations over time suggested that applied experimental concentrations may overestimate concentrations necessary for phytotoxicity by over an order of magnitude. (+/--Catechin was not phytotoxic to Bambusa arundinacea in natural Indian soil in a single pulse, but soil concentrations at the time of planting seeds were either undetectable or very low. However, a single dose of (+/--catechin suppressed the growth of bamboo in sand, in soil mixed with organic matter, and Koeleria macrantha in soils from Montana and Romania, and in field applications at 40 microg l(-1. Multiple pulses of (+/--catechin were inhibitory at very low concentrations in Indian soil. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that (+/--catechin is highly dynamic in natural soils, but is phytotoxic well below natural concentrations measured in some soils and applied

  4. Phytotoxic Effects of (±)-Catechin In vitro, in Soil, and in the Field

    Science.gov (United States)

    Inderjit; Pollock, Jarrod L.; Callaway, Ragan M.; Holben, William

    2008-01-01

    Background Exploring the residence time of allelochemicals released by plants into different soils, episodic exposure of plants to allelochemicals, and the effects of allelochemicals in the field has the potential to improve our understanding of interactions among plants. Methodology/Principal Findings We conducted experiments in India and the USA to understand the dynamics of soil concentrations and phytotoxicity of (±)-catechin, an allelopathic compound exuded from the roots of Centaurea maculosa, to other plants in vitro and in soil. Experiments with single and pulsed applications into soil were conducted in the field. Experimental application of (±)-catechin to soils always resulted in concentrations that were far lower than the amounts added but within the range of reported natural soil concentrations. Pulses replenished (±)-catechin levels in soils, but consistently at concentrations much lower than were applied, and even pulsed concentrations declined rapidly. Different natural soils varied substantially in the retention of (±)-catechin after application but consistent rapid decreases in concentrations over time suggested that applied experimental concentrations may overestimate concentrations necessary for phytotoxicity by over an order of magnitude. (±)-Catechin was not phytotoxic to Bambusa arundinacea in natural Indian soil in a single pulse, but soil concentrations at the time of planting seeds were either undetectable or very low. However, a single dose of (±)-catechin suppressed the growth of bamboo in sand, in soil mixed with organic matter, and Koeleria macrantha in soils from Montana and Romania, and in field applications at 40 µg l−1. Multiple pulses of (±)-catechin were inhibitory at very low concentrations in Indian soil. Conclusions/Significance Our results demonstrate that (±)-catechin is highly dynamic in natural soils, but is phytotoxic well below natural concentrations measured in some soils and applied at low concentrations in

  5. Phytotoxicity of vulpia residues: III. Biological activity of identified allelochemicals from Vulpia myuros.

    Science.gov (United States)

    An, M; Pratley, J E; Haig, T

    2001-02-01

    Twenty compounds identified in vulpia (Vulpia myuros) residues as allelochemicals were individually and collectively tested for biological activity. Each exhibited characteristic allelochemical behavior toward the test plant, i.e., inhibition at high concentrations and stimulation or no effect at low concentrations, but individual activities varied. Allelopathins present in large quantities, such as syringic, vanillic, and succinic acids, possessed low activity, while those present in small quantities, such as catechol and hydrocinnamic acid, possessed strong inhibitory activity. The concept of a phytotoxic strength index was developed for quantifying the biological properties of each individual allelopathin in a concise, comprehensive, and meaningful format. The individual contribution of each allelopathin, assessed by comparing the phytotoxic strength index to the overall toxicity of vulpia residues, was variable according to structure and was influenced by its relative proportion in the residue. The majority of compounds possessed low or medium biological activity and contributed most of the vulpia phytotoxicity, while compounds with high biological activity were in the minority and only present at low concentration. Artificial mixtures of these pure allelochemicals also produced phytotoxicity. There were additive/synergistic effects evident in the properties of these mixtures. One such mixture, formulated from allelochemicals found in the same proportions as occur in vulpia extract, produced stronger activity than another formulated from the same set of compounds but in equal proportions. These results suggest that the exploration of the relative composition of a cluster of allelopathins may be more important than simply focusing on the identification of one or two compounds with strong biological activity and that synergism is fundamental to the understanding of allelopathy.

  6. Suitability of some growth characteristics to indicate phytotoxicity in pot experiments on maize test plants

    International Nuclear Information System (INIS)

    Bujtas, K.

    1994-01-01

    Assessment of phytotoxic conditions is often based on measuring the dry matter production of plants, although other growth characteristics may be more sensitive indicators of toxic circumstances. Purpose of this study was to evaluate the suitability of such variables as fresh weight, dry matter accumulation of shoots, longitudinal growth of leaves, and correlations between these variables for quantifying phytotoxicity caused by provocative rates of a lenacil-based herbicide. Impact of soil texture and soil pH on the manifestation of toxic symptoms were also investigated in a pot experiment on three soil types with maize (Zea mays L. cv. Carla) as test plant. Although the external circumstances were much different from field conditions, the observed differences in the phytotoxicity on the three soils were consistent with the application recommendations of the herbicide. High toxicities were observed on acidic sandy soil, and less on a similarly acidic soil of heavier texture. In contrast, slight stimulations were observed on chernozem soil at application rates lower than or corresponding to recommended field rates. Sum of the lengths of the leaves was a relatively sensitive indicator of bioactivity, showing cumulatively the effects observed for the individual leaves. Correlations between fresh weight/dry matter accumulation and fresh weight/sum of the lengths of leaves were shown to be linear over the application range, with slopes depending mostly on soil texture, and less so on soil pH. The results indicate that the suitability of the investigated variables for assessing phytotoxicity may be different on the different soil types. (author)

  7. Purification and Phytotoxic Analysis of Botrytis cinerea Virulence Factors: New Avenues for Crop Protection

    Directory of Open Access Journals (Sweden)

    Maria R. Davis

    2012-07-01

    Full Text Available Botrytis cinerea is a necrotrophic fungus infecting over 230 plant species worldwide. This highly adaptable pathogen can afflict agricultural products from seed to storage, causing significant economic losses and instability in the food supply. Small protein virulence factors secreted by B. cinerea during infection play an important role in initiation and spread of disease. BcSnod1 was found to be abundantly expressed upon exposure to media containing strawberry extract. From sequence similarity, BcSnod2 was also identified and both were recognized as members of the Ceratoplatanin family of small phytotoxic proteins. Recombinant BcSnod1 was shown to have a phytotoxic effect and play an important role in pathogenicity while the role of BcSnod2 remains less clear. Both bacterial and yeast production systems are reported, though the bacterial protein is less toxic and mostly unfolded relative to that made in yeast. Compared to BcSnod1, recombinant bacterial BcSnod2 shows similar, but delayed phytotoxicity on tomato leaves. Further studies of these critical virulence factors and their inhibition promise to provide new avenues for crop protection.

  8. Phytotoxicity of pesticides mancozeb and chlorpyrifos: correlation with the antioxidative defence system in Allium cepa.

    Science.gov (United States)

    Fatma, Firdos; Verma, Sonam; Kamal, Aisha; Srivastava, Alka

    2018-02-01

    Pesticides are a group of chemical substances which are widely used to improve agricultural production. However, these substances could be persistent in soil and water, accumulative in sediment or bio-accumulative in biota depending on their solubility, leading to different types of environmental pollution. The present study was done to assess the impact of pesticides-mancozeb and chlorpyrifos, via morphological and physiological parameters using Allium cepa test system. Phytotoxic effects of pesticides were examined via germination percentage, survival percentage, root and shoot length, root shoot length ratio, seedling vigor index, percentage of phytotoxicity and tolerance index. Oxidative stress on Allium seedlings caused by pesticides was also assessed by investigating the activity of antioxidative enzymes viz. catalase, peroxidase and superoxide dismutase. Correlation was worked out between morphological parameters and antioxidative enzymes to bring out the alliance between them. Mancozeb and chlorpyrifos concentrations were significantly and positively correlated with the activity of antioxidative enzymes and negatively correlated with morphological parameters. Significant positive correlation between various morphological parameters showed their interdependency. However, negative correlation was obtained between activity of antioxidative enzymes and morphological parameters. The enzymes however, showed positive correlation with each other. Based on our result we can conclude that all morphological parameters were adversely affected by the two pesticides as reflected by phytotoxicity in Allium . Their negative correlation with activity of antioxidative enzymes indicates that upregulation of antioxidative enzymes is not sufficient to overcome the toxic effect, thereby signifying the threat being caused by the regular use of these pesticides.

  9. Phytotoxicity and biodirected fractionation of extracts of barks of Blepharocalyx salicifolius (Kunth O.Berg. (Myrtaceae

    Directory of Open Access Journals (Sweden)

    Eduardo Habermann

    2015-02-01

    Full Text Available This study aimed to evaluate the phytotoxicity of extracts and fractions of barks of Blepharocalyx salicifolius on elongation of etiolated coleoptiles of Triticum aestivum (wheat. The extracts hexane (Hx, ethyl acetate (AcOET, and aqueous (H2O were obtained by means of exhaustive extraction with CH2Cl2/CH3OH and subsequent fractionation by partition chromatography coefficient. The extracts AcOET and Hx were fractionated by column chromatography by using organic solvents in increasing order of polarity, yielding 7 hexanic fractions and 6 ethylic acetate fractions. Subsequently, the fractions Hx1 and Hx5 were subfractionated by column chromatography. The extracts AcOET and Hx inhibited elongation of coleoptiles. Four ethylic acetate fractions inhibited elongation of coleoptiles at all concentrations. Five hexanic fractions inhibited elongation of coleoptiles, the fractions Hx5 and Hx1 fractions showed phytotoxic effects equivalent or superior to those observed by the herbicide GOAL® at the same concentrations. All subfractions obtained by means of fractionation of Hx1 inhibited elongation of coleoptiles. Six fractions obtained by means of fractionation of Hx5 inhibited elongation of coleoptiles at all concentrations. This study proves the phytotoxicity of extracts of barks of B. salicifolius, providing indications that they may act as promising natural herbicides.

  10. Phytotoxic risk assessment of ambient air pollution on agricultural crops in Selangor State, Malaysia

    International Nuclear Information System (INIS)

    Ishii, S.; Bell, J.N.B.; Marshall, F.M.

    2007-01-01

    The phytotoxic risk of ambient air pollution to local vegetation was assessed in Selangor State, Malaysia. The AOT40 value was calculated by means of the continuously monitored daily maximum concentration and the local diurnal pattern of O 3 . Together with minor risks associated with the levels of NO 2 and SO 2 , the study found that the monthly AOT40 values in these peri-urban sites were consistently over 1.0 ppm.h, which is well in exceedance of the given European critical level. Linking the O 3 level to actual agricultural crop production in Selangor State also indicated that the extent of yield losses could have ranged from 1.6 to 5.0% (by weight) in 2000. Despite a number of uncertainties, the study showed a simple but useful methodological framework for phytotoxic risk assessment with a limited data set, which could contribute to appropriate policy discussion and countermeasures in countries under similar conditions. - There is a large potential of phytotoxic risk on vegetation in Selangor State, Malaysia

  11. Tabled Execution in Scheme

    Energy Technology Data Exchange (ETDEWEB)

    Willcock, J J; Lumsdaine, A; Quinlan, D J

    2008-08-19

    Tabled execution is a generalization of memorization developed by the logic programming community. It not only saves results from tabled predicates, but also stores the set of currently active calls to them; tabled execution can thus provide meaningful semantics for programs that seemingly contain infinite recursions with the same arguments. In logic programming, tabled execution is used for many purposes, both for improving the efficiency of programs, and making tasks simpler and more direct to express than with normal logic programs. However, tabled execution is only infrequently applied in mainstream functional languages such as Scheme. We demonstrate an elegant implementation of tabled execution in Scheme, using a mix of continuation-passing style and mutable data. We also show the use of tabled execution in Scheme for a problem in formal language and automata theory, demonstrating that tabled execution can be a valuable tool for Scheme users.

  12. FIXING HEALTH SYSTEMS / Executive Summary (2008 update ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2010-12-14

    Dec 14, 2010 ... FIXING HEALTH SYSTEMS / Executive Summary (2008 update) ... In several cases, specific approaches recommended by the TEHIP team have been acted upon regionally and internationally, including the ... Related articles ...

  13. Tutoring executives online

    DEFF Research Database (Denmark)

    Bignoux, Stephane; Sund, Kristian J.

    2018-01-01

    Studies of learning and student satisfaction in the context of online university programmes have largely neglected programmes catering specifically to business executives. Such executives have typically been away from higher education for a number of years, and have collected substantial practical...... experience in the subject matters they are taught. Their expectations in terms of both content and delivery may therefore be different from non-executive students. We explore perceptions of the quality of tutoring in the context of an online executive MBA programme through participant interviews. We find...... that in addition to some of the tutor behaviours already discussed in the literature, executive students look specifically for practical industry knowledge and experience in tutors, when judging how effective a tutor is. This has implications for both the recruitment and training of online executive MBA tutors....

  14. Tutoring Executives Online

    DEFF Research Database (Denmark)

    Bignoux, Stephane; Sund, Kristian J.

    2016-01-01

    Studies of learning and student satisfaction in the context of online university programs have largely neglected programs catering specifically to business executives. Such executives have typically been away from higher education for a number of years, and have collected substantial practical...... experience in the subject matters they are taught. Their expectations in terms of both content and delivery may therefore be different from non-executive students. We explore perceptions of the quality of tutoring in the context of an online executive MBA program through participant interviews. We find...... that in addition to some of the tutor behaviors already discussed in the literature, executive students look specifically for practical industry knowledge and experience in tutors, when judging how effective a tutor is. This has implications for both the recruitment and training of online executive MBA tutors....

  15. Phyto-toxicity and Phyto-remediation Potential of Mercury in Indian Mustard and Two Ferns with Mercury Contaminated Water and Oak Ridge Soil

    International Nuclear Information System (INIS)

    Su, Y.; Han, F.X.; Chen, J.; Shiyab, S.; Monts, D.L.; Monts, D.L.

    2009-01-01

    Phyto-remediation is an emerging technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. Certain fern and Indian mustard species have been suggested as candidates for phyto-remediation of heavy metal-contaminated soil and water because of their high efficiency of accumulating metals in shoots and their high biomass production. Currently, no known hyper-accumulator plants for mercury have been found. Here we report the Hg uptake and phyto-toxicity by two varieties of fern and Indian mustard. Their potential for Hg phyto-remediation application was also investigated. Anatomical, histochemical and biochemical approaches were used to study mercury phyto-toxicity as well as anti-oxidative responses in ferns [Chinese brake fern (P. vittata) and Boston fern (N. exaltata)] and Indian mustard (Florida broadleaf and longstanding) (Brassica juncea L.) grown in a hydroponic system. Phyto-remediation potentials of these plant species were estimated based on their Hg uptake performance with contaminated soils from Oak Ridge (TN, USA). Our results show that mercury exposure led to severe phyto-toxicity accompanied by lipid peroxidation and rapid accumulation of hydrogen peroxide (H 2 O 2 ) in P. vittata, but not in N. exaltata. The two cultivars of fern responded differently to mercury exposure in terms of anti-oxidative enzymes (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD; glutathione reductase, GR). Mercury exposure resulted in the accumulation of ascorbic acid (ASA) and glutathione (GSH) in the shoots of both cultivars of fern. On the other hand, Indian mustard effectively generated an enzymatic antioxidant defense system (especially CAT) to scavenge H 2 O 2 , resulting in lower H 2 O 2 in shoots with higher mercury concentrations. These two cultivars of Indian mustard demonstrated an efficient metabolic defense and adaptation system to mercury-induced oxidative stress. In both varieties of fern and Indian

  16. Phytotoxic Activity of Ocimum tenuiflorum Extracts on Germination and Seedling Growth of Different Plant Species

    Directory of Open Access Journals (Sweden)

    A. K. M. Mominul Islam

    2014-01-01

    Full Text Available Phytotoxic activity of Ocimum tenuiflorum (Lamiaceae plant extracts was investigated against the germination and seedling growth of cress (Lepidium sativum, lettuce (Lactuca sativa, alfalfa (Medicago sativa, Italian ryegrass (Lolium multiflorum, barnyard grass (Echinochloa crus-galli, and timothy (Phleum pratense at four different concentrations. The plant extracts at concentrations greater than 30 mg dry weight equivalent extract mL−1 reduced significantly the total germination percent (GP, germination index (GI, germination energy (GE, speed of emergence (SE, seedling vigour index (SVI, and coefficient of the rate of germination (CRG of all test species except barnyard grass and GP of lettuce. In contrast, time required for 50% germination (T50 and mean germination time (MGT were increased at the same or higher than this concentration. The increasing trend of T50 and MGT and the decreasing trend of other indices indicated a significant inhibition or delay of germination of the test species by O. tenuiflorum plant extracts and vice versa. In addition, the shoot and root growth of all test species were significantly inhibited by the extracts at concentrations greater than 10 mg dry weight equivalent extract mL−1. The I50 values for shoot and root growth were ranged from 26 to 104 mg dry weight equivalent extract mL−1. Seedling growth was more sensitive to the extracts compared to seed germination. Results of this study suggest that O. tenuiflorum plant extracts have phytotoxic properties and thus contain phytotoxic substances. Isolation and characterization of those substances from this plant may act as a tool for new natural, biodegradable herbicide development to control weeds.

  17. Effectiveness of amendments on the spread and phytotoxicity of contaminants in metal-arsenic polluted soil

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, V., E-mail: vga220@ual.es [Departamento de Edafologia y Quimica Agricola, ESI CITE IIB, Universidad de Almeria, Carretera de Sacramento s/n, 04129 Almeria (Spain); Garcia, I.; Del Moral, F.; Simon, M. [Departamento de Edafologia y Quimica Agricola, ESI CITE IIB, Universidad de Almeria, Carretera de Sacramento s/n, 04129 Almeria (Spain)

    2012-02-29

    Highlights: Black-Right-Pointing-Pointer The effectiveness of soil amendments was studied in lixiviates and in pore water. Black-Right-Pointing-Pointer Heavy metals and arsenic showed different partitioning. Black-Right-Pointing-Pointer The amendment which was effective against arsenic was not effective against metals. Black-Right-Pointing-Pointer The amendment that fixed metals increased the arsenic concentration in lixiviates. Black-Right-Pointing-Pointer Using amendments in combination did not improve the effectiveness. - Abstract: A metal-arsenic polluted soil from sulphide-mine waste was treated, in all possible combinations, with two different amounts of marble sludge (98% CaCO{sub 3}), compost (41% organic carbon), and Byferrox (70% Fe). Lixiviate and pore water from each treated and untreated soil were analysed, and lettuce-seed bioassays were performed. None of the treatments decreased the electrical conductivity of lixiviates or the concentrations of all pollutants found in both solutions. Marble sludge and compost increased the pH values and decreased the zinc, cadmium, copper, and lead concentrations in both solutions while increasing the arsenic concentrations in the lixiviates. Byferrox did not alter the physicochemical parameters or the concentrations of zinc, cadmium, copper, or lead in either solution but significantly decreased the arsenic concentrations in pore water. Compared with the Byferrox treatment, the mixture of marble sludge and Byferrox decreased redox potential values, increasing the arsenic concentrations in both solutions and the electrical conductivity of the pore water. All lixiviates were highly phytotoxic and seeds did not germinate. Pore-water phytotoxicity was related to electrical conductivity values and heavy-metal concentrations. The combination of marble sludge and compost was most effective at diminishing toxicity in lettuce. The soils treated with Byferrox, alone or mixed with marble sludge or compost, were the most

  18. Effectiveness of amendments on the spread and phytotoxicity of contaminants in metal–arsenic polluted soil

    International Nuclear Information System (INIS)

    González, V.; García, I.; Del Moral, F.; Simón, M.

    2012-01-01

    Highlights: ► The effectiveness of soil amendments was studied in lixiviates and in pore water. ► Heavy metals and arsenic showed different partitioning. ► The amendment which was effective against arsenic was not effective against metals. ► The amendment that fixed metals increased the arsenic concentration in lixiviates. ► Using amendments in combination did not improve the effectiveness. - Abstract: A metal–arsenic polluted soil from sulphide-mine waste was treated, in all possible combinations, with two different amounts of marble sludge (98% CaCO 3 ), compost (41% organic carbon), and Byferrox (70% Fe). Lixiviate and pore water from each treated and untreated soil were analysed, and lettuce-seed bioassays were performed. None of the treatments decreased the electrical conductivity of lixiviates or the concentrations of all pollutants found in both solutions. Marble sludge and compost increased the pH values and decreased the zinc, cadmium, copper, and lead concentrations in both solutions while increasing the arsenic concentrations in the lixiviates. Byferrox did not alter the physicochemical parameters or the concentrations of zinc, cadmium, copper, or lead in either solution but significantly decreased the arsenic concentrations in pore water. Compared with the Byferrox treatment, the mixture of marble sludge and Byferrox decreased redox potential values, increasing the arsenic concentrations in both solutions and the electrical conductivity of the pore water. All lixiviates were highly phytotoxic and seeds did not germinate. Pore-water phytotoxicity was related to electrical conductivity values and heavy-metal concentrations. The combination of marble sludge and compost was most effective at diminishing toxicity in lettuce. The soils treated with Byferrox, alone or mixed with marble sludge or compost, were the most phytotoxic.

  19. Foliar phosphite application has minor phytotoxic impacts across a diverse range of conifers and woody angiosperms.

    Science.gov (United States)

    Scott, Peter; Bader, Martin Karl-Friedrich; Williams, Nari Michelle

    2016-10-01

    Phytophthora plant pathogens cause tremendous damage in planted and natural systems worldwide. Phosphite is one of the only effective chemicals to control broad-scale Phytophthora disease. Little work has been done on the phytotoxic effects of phosphite application on plant communities especially in combination with plant physiological impacts. Here, we tested the phytotoxic impact of phosphite applied as foliar spray at 0, 12, 24 and 48 kg a.i. ha(-1) . Eighteen-month-old saplings of 13 conifer and angiosperm species native to New Zealand, and two exotic coniferous species were treated and the development of necrotic tissue and chlorophyll-a-fluorescence parameters (optimal quantum yield, Fv /Fm ; effective quantum yield of photosystem II, ΦPSII ) were assessed. In addition, stomatal conductance (gs ) was measured on a subset of six species. Significant necrosis assessed by digital image analysis occurred in only three species: in the lauraceous canopy tree Beilschmiedia tawa (8-14%) and the understory shrub Dodonaea viscosa (5-7%) across phosphite concentrations and solely at the highest concentration in the myrtaceous pioneer shrub Leptospermum scoparium (66%). In non-necrotic tissue, Fv /Fm , ΦPSII and gs remained unaffected by the phosphite treatment. Overall, our findings suggest minor phytotoxic effects resulting from foliar phosphite application across diverse taxa and regardless of concentration. This study supports the large-scale use of phosphite as a management tool to control plant diseases caused by Phytophthora pathogens in plantations and natural ecosystems. Long-term studies are required to ascertain potential ecological impacts of repeated phosphite applications. © 2016 Scandinavian Plant Physiology Society.

  20. Cytotoxic, phytotoxic, and mutagenic appraisal to ascertain toxicological potential of particulate matter emitted from automobiles.

    Science.gov (United States)

    Anwar, Khaleeq; Ejaz, Sohail; Ashraf, Muhammad; Altaf, Imran; Anjum, Aftab Ahmad

    2013-07-01

    Vehicular air pollution is a mounting health issue of the modern age, particularly in urban populations of the developing nations. Auto-rickshaws are not considered eco-friendly as to their inefficient engines producing large amount of particulate matter (PM), thus posing significant environmental threat. The present study was conducted to ascertain the cytotoxic, phytotoxic, and mutagenic potential of PM from gasoline-powered two-stroke auto-rickshaws (TSA) and compressed natural gas-powered four-stroke auto-rickshaws (FSA). Based on the increased amount of aluminum quantified during proton-induced X-ray emission analysis of PM from TSA and FSA, different concentrations of aluminum sulfate were also tested to determine its eco-toxicological potential. The MTT assay demonstrated significant (p < 0.001) dose-dependent cytotoxic effects of different concentrations of TSA, FSA, and aluminum sulfate on BHK-21 cell line. LC50 of TSA, FSA, and aluminum sulfate was quantified at 16, 11, and 23.8 μg/ml, respectively, establishing PM from FSA, a highly cytotoxic material. In case of phytotoxicity screening using Zea mays, the results demonstrated that all three tested materials were equally phytotoxic at higher concentrations producing significant reduction (p < 0.001) in seed germination. Aluminum sulfate proved to be a highly phytotoxic agent even at its lowest concentration. Mutagenicity was assessed by fluctuation Salmonella reverse mutation assay adopting TA100 and TA98 mutant strains with (+S9) and without (-S9) metabolic activation. Despite the fact that different concentrations of PM from both sources, i.e., TSA and FSA were highly mutagenic (p < 0.001) even at lower concentrations, the mutagenic index was higher in TSA. Data advocate that all tested materials are equally ecotoxic, and if the existing trend of atmospheric pollution by auto-rickshaws is continued, airborne heavy metals will seriously affect the normal growth of local inhabitants and

  1. Chemical Composition and Possible in Vitro Phytotoxic Activity of Helichrsyum italicum (Roth Don ssp. italicum

    Directory of Open Access Journals (Sweden)

    Vincenzo De Feo

    2011-09-01

    Full Text Available The chemical composition of the essential oil of Helichrysum italicum (Roth Don ssp. italicum, collected in the National Park of Cilento and Diano Valley, Southern Italy, was studied by means of GC and GC/MS. Forty four compounds of 45 constituents were identified in the oil, mainly oxygenated sesquiterpenes. The essential oil was evaluated for its potential in vitro phytotoxic activity against germination and early radicle elongation of radish and garden cress. The radicle elongation of radish was significantly inhibited at the highest doses tested, while germination of both seeds was not affected.

  2. Phytotoxicity and Benzoxazinone Concentration in Field Grown Cereal Rye (Secale cereale L.)

    OpenAIRE

    La Hovary, C.; Danehower, D. A.; Ma, G.; Reberg-Horton, C.; Williamson, J. D.; Baerson, S. R.; Burton, J. D.

    2016-01-01

    Winter rye (Secale cereale L.) is used as a cover crop because of the weed suppression potential of its mulch. To gain insight into the more effective use of rye as a cover crop we assessed changes in benzoxazinone (BX) levels in rye shoot tissue over the growing season. Four rye varieties were planted in the fall and samples harvested at intervals the following spring. Two different measures of phytotoxic compound content were taken. Seed germination bioassays were used as an estimate of tot...

  3. Phytotoxicity: An Overview of the Physiological Responses of Plants Exposed to Fungicides

    Directory of Open Access Journals (Sweden)

    Maria Celeste Dias

    2012-01-01

    Full Text Available In the last decades, the use of fungicides in agriculture for fungi diseases control has become crucial. Fungicide research has produced a diverse range of products with novel modes of action. However, the extensive use of these compounds in the agriculture system raises public concern because of the harmful potential of such substances in the environment and human health. Moreover, the phytotoxic effects of some fungicides are already recognized but little is known about the impact of these compounds on the photosynthetic apparatus. This paper presents a comprehensive overview of the literature considering different classes of fungicides and their effects on plant physiology, with particular emphasis on photosynthesis.

  4. Executive functioning in pre-school children with autism spectrum disorders: The relationship between executive functioning and language

    OpenAIRE

    Linnerud, Ida Cathrine Wang

    2014-01-01

    Background: Executive function difficulties are prevalent in children with autism spectrum disorders (ASD) and there are several indications of a modifying relationship between executive functions and language in children. However, there is limited research on the relationship between executive functioning and language in young children with ASD. The current study compared real-world executive functioning between groups of children with ASD, language disorders (LD), and typical development (T...

  5. Enantioselective Separation of 4,8-DHT and Phytotoxicity of the Enantiomers on Various Plant Species.

    Science.gov (United States)

    Yang, Li; Ma, Xiao-Yan; Ruan, Xiao; Jiang, De-An; Pan, Cun-De; Wang, Qiang

    2016-04-22

    As a candidate for bioherbicide, 4,8-dihydroxy-1-tetralone (4,8-DHT) was isolated from Caryospora callicarpa epicarp and its two enantiomers, S-(+)-isosclerone and R-(-)-regiolone, were separated by chiral high-performance liquid chromatography (HPLC) on a Chiralcel OD column with chiral stationary phase (CSP)-coated cellulose-tris(3,5-dimethylphenylcarbamate). Then, the phytotoxicity of 4,8-DHT and its enantiomers toward the seeds germination and seedling growth of the five tested plant species, including lettuce (Latuca sativa), radish (Raphanus sativus), cucumber (Cucumis sativus), onion (Allium cepa), and wheat (Triticum aestivum), were investigated and the results indicated a hormesis at low concentration of 4,8-DHT and its enantiomers, but a retardant effect at high concentration. Between the two enantiomers of 4,8-DHT, the S-(+)-isosclerone was more toxic to seeds germination and seedling growth of the five tested plant species than the R-(-)-regiolone, and also the phytotoxicity of S-(+)-isosclerone varied with different plants. For example, S-(+)-isosclerone was the most active to seedling growth of lettuce, indicating that S-(+)-isosclerone had specific effects on different organisms. Thus, all of the chirality and concentration of 4,8-DHT, as well as the affected plant species, need to be taken into consideration in the development and utilization of 4,8-DHT.

  6. Ozone distribution and phytotoxic potential in mixed conifer forests of the San Bernardino Mountains, southern California

    International Nuclear Information System (INIS)

    Bytnerowicz, Andrzej; Arbaugh, Michael; Schilling, Susan; Fraczek, Witold; Alexander, Diane

    2008-01-01

    In the San Bernardino Mountains of southern California, ozone (O 3 ) concentrations have been elevated since the 1950s with peaks reaching 600 ppb and summer seasonal averages >100 ppb in the 1970s. During that period increased mortality of ponderosa and Jeffrey pines occurred. Between the late 1970s and late1990s, O 3 concentrations decreased with peaks ∼180 ppb and ∼60 ppb seasonal averages. However, since the late 1990s concentrations have not changed. Monitoring during summers of 2002-2006 showed that O 3 concentrations (2-week averages) for individual years were much higher in western sites (58-69 ppb) than eastern sites (44-50 ppb). Potential O 3 phytotoxicity measured as various exposure indices was very high, reaching SUM00 - 173.5 ppm h, SUM60 - 112.7 ppm h, W126 - 98.3 ppm h, and AOT40 - 75 ppm h, representing the highest values reported for mountain areas in North America and Europe. - Although peak ozone concentrations have greatly decreased in the San Bernardino Mountains, very high ozone phytotoxic potential remains

  7. Antioxidant, phytotoxic and cytotoxic activity of methanolic extract of Trigonella foenum-graecum

    Directory of Open Access Journals (Sweden)

    Amin Ullah

    2016-05-01

    Full Text Available Objective: To analyze the methanol extract of Trigonella foenum-graecum (T. foenumgraecum for antioxidant, phytotoxic and cytotoxic activity. Methods: The powder of T. foenum-graecum was extracted in diluted methanol with the help of random shaking method. All extracts of the plant were measured for cytotoxic activity (beside brine shrimp and antioxidant activity vs. 1, 1-diphenyl-2-picrylhydrazyl free radical. Results: Various concentrations of methanolic extract of T. foenum-graecum were observed as 36.16% to 54.12% with rising concentrations of 50 to 1000 μg/mL. Significantly phytotoxic activity (100 and 1000 μg/mL reduced the growth of roots (radicals and shoots (hypocotyls of rice when compared to control after 3 and 7 days’ treatment. At a concentration of 10 μg/ mL, the survival rate of cytotoxic activity of brine shrimp was maximum and at a concentration of 250 μg/mL, the death rate of brine shrimp was maximum. Conclusions: T. foenum-graecum has potential activity against free radical mediated sickness and thus it is possible to treat cancer.

  8. Biochemical characterization of systemic bacteria in bananas, sensitivity to antibiotics and plant phytotoxicity during shoot proliferation

    Directory of Open Access Journals (Sweden)

    Janiffe Peres de Oliveira

    2016-04-01

    Full Text Available The objective of this work was to characterize the biochemically systemic bacterial isolated from banana plants, to evaluate the bacterial sensitivity to antibiotics, and to determine the phytotoxicity of banana shoots during in vitro proliferation. Systemic bacteria belonging to the Klebsiella and Aeromonas genera were isolated from the “Maravilha” (FHIA 01 AAAB, “Preciosa” (PV 4285 AAAB and “Thap Maeo” (AAB varieties and were then characterized. Tests of shoot sensitivity to antibiotics were performed, and the minimum inhibitory concentration (MIC and phytotoxic effects of selected antibiotics to plants were determined. Among the 20 antibiotics evaluated, the strains showed sensitivity to cefaclor, cefalexin, cefalotin, nalidixic acid, chloramphenicol, and vancomycin. However, during MIC determination, the best results were obtained with cefaclor, vancomycin or nalidixic acid alone in concentrations ranging from 512 to 1,024 mg L-1. In culture medium, cefaclor at 1,024 mg L-1 was the only antibiotic to affect the multiplication and the shoot survival in culture.

  9. Phytotoxicity and Chemical Characterization of Compost Derived from Pig Slurry Solid Fraction for Organic Pellet Production

    Directory of Open Access Journals (Sweden)

    Niccolò Pampuro

    2017-11-01

    Full Text Available The phytotoxicity of four different composts obtained from pig slurry solid fraction composted by itself (SSFC and mixed with sawdust (SC, woodchips (WCC and wheat straw (WSC was tested with bioassay methods. For each compost type, the effect of water extracts of compost on seed germination and primary root growth of cress (Lepidium Sativum L. was investigated. Composts were also chemically analysed for total nitrogen, ammonium, electrical conductivity and heavy metal (Cu and Zn. The chemicals were correlated to phytotoxicity indices. The mean values of the germination index (GI obtained were 160.7, 187.9, 200.9 and 264.4 for WSC, WCC, SC and SSFC, respectively. Growth index (GrI ranged from the 229.4%, the highest value, for SSFC, followed by 201.9% for SC, and 193.1% for WCC, to the lowest value, 121.4%, for WSC. Electrical conductivity showed a significant and negative correlation with relative seed germination at the 50% and 75% concentrations. A strong positive correlation was found for water-extractable Cu with relative root growth and germination index at the 10% concentration. Water-extractable Zn showed a significant positive correlation with relative root growth and GI at the 10% concentration. These results highlighted that the four composts could be used for organic pellet production and subsequently distributed as a soil amendment with positive effects on seed germination and plant growth (GI > 80%.

  10. Relationships between Chemical Characteristics and Phytotoxicity of Biochar from Poultry Litter Pyrolysis.

    Science.gov (United States)

    Rombolà, Alessandro G; Marisi, Giovanni; Torri, Cristian; Fabbri, Daniele; Buscaroli, Alessandro; Ghidotti, Michele; Hornung, Andreas

    2015-08-05

    Three biochars were prepared by intermediate pyrolysis from poultry litter at different temperatures (400, 500, and 600 °C with decreasing residence times) and compared with biochars from corn stalk prepared under the same pyrolysis conditions. The phytotoxicity of these biochars was estimated by means of seed germination tests on cress (Lepidium sativum L.) conducted in water suspensions (at 2, 5, and 40 g/L) and on biochars wetted according to their water-holding capacity. Whereas the seeds germinated after 72 h in water suspensions with corn stalk biochar were similar to the control (water only), significant inhibition was observed with poultry litter biochars. In comparison to corn stalk, poultry litter generated biochars with higher contents of ash, ammonium, nitrogen, and volatile fatty acids (VFAs) and a similar concentration of polycyclic aromatic hydrocarbons (PAHs). Results from analytical pyrolysis (Py-GC-MS) indicated that nitrogen-containing organic compounds (NCCs) and aliphatic components were distinctive constituents of the thermally labile fraction of poultry litter biochar. The inhibition of germination due to poultry litter biochar produced at 400 °C (PL400) was suppressed after solvent extraction or treatment with active sludge. A novel method based on solid-phase microextraction (SPME) enabled the identification of mobile organic compounds in PL400 capable of being released in air and water, including VFAs and NCCs. The higher phytotoxicity of poultry litter than corn biochars was tentatively attributed to hydrophilic biodegradable substances derived from lipids or proteins removable by water leaching or microbial treatments.

  11. Phytotoxic effects of aqueous leaf extracts of four Myrtaceae species on three weeds

    Directory of Open Access Journals (Sweden)

    Maristela Imatomi

    2015-05-01

    Full Text Available Research on allelopathic interactions can be useful in the search for phytotoxins produced by plants that may be employed as natural herbicides. The aim of this study was to assess the phytotoxic action of aqueous leaf extract of Blepharocalyx salicifolius, Myrcia multiflora, Myrcia splendens and Myrcia tomentosa on the germination and development of three weeds. The working hypothesis was that leaf extracts of Myrtaceae may negatively influence the development of weed species. Aqueous leaf extracts at 5 and 10% (g mL-1 were tested on the germination and growth of Euphorbia heterophylla, Echinochloa crus-galli and Ipomoea grandifolia and compared with the herbicide oxyfluorfen and distilled water (control. The most extracts caused pronounced delays in seed germination and inhibited the growth of seedlings of E. heterophylla; I. grandifolia and E. crus-galli, with the last target species had no growth shoot inhibited by the extracts. In this study, the potential and efficiency of the tested aqueous leaf extracts were evident because they were more phytotoxic to the weeds than the herbicide. Thus, the aqueous extracts of leaves from Myrtaceae species show potential for the isolation of active compounds that can be used for the production of natural herbicides in the future.

  12. Natural products phytotoxicity A bioassay suitable for small quantities of slightly water-soluble compounds.

    Science.gov (United States)

    Dornbos, D L; Spencer, G F

    1990-02-01

    A large variety of secondary metabolites that can inhibit germination and/or seedling growth are produced by plants in low quantities. The objective of this study was to develop a bioassay capable of reliably assessing reductions in germination percentage and seedling length of small-seeded plant species caused by exposure to minute quantities of these compounds. The germination and growth of alfalfa (Medicago saliva), annual ryegrass (Lolium multiflorum), and velvetleaf (Abutilon theophrasti) were evaluated against six known phytotoxins from five chemical classes; cinmethylin (a herbicidal cineole derivative) was selected as a comparison standard. Each phytotoxin, dissolved in a suitable organic solvent, was placed on water-agar in small tissue culture wells. After the solvent evaporated, imbibed seeds were placed on the agar; after three days, germination percentages and seedling lengths were measured. Compared to a commonly used filter paper procedure, this modified agar bioassay required smaller quantities of compound per seed for comparable bioassay results. This bioassay also readily permitted the measurement of seedling length, a more sensitive indicator of phytotoxicity than germination. Seedling length decreased sigmoidally as the toxin concentration increased logarithmically. Phytotoxicity was a function of both compound and plant species. Cinmethylin, a grass herbicide, reduced the length of annual ryegrass seedlings by 90-100%, whereas that of alfalfa and velvetleaf was inhibited slightly. The agar bioassay facilitated the rapid and reliable testing of slightly water-soluble compounds, requiring only minute quantities of each compound to give reproducible results.

  13. Enantioselective Separation of 4,8-DHT and Phytotoxicity of the Enantiomers on Various Plant Species

    Directory of Open Access Journals (Sweden)

    Li Yang

    2016-04-01

    Full Text Available As a candidate for bioherbicide, 4,8-dihydroxy-1-tetralone (4,8-DHT was isolated from Caryospora callicarpa epicarp and its two enantiomers, S-(+-isosclerone and R-(−-regiolone, were separated by chiral high-performance liquid chromatography (HPLC on a Chiralcel OD column with chiral stationary phase (CSP-coated cellulose-tris(3,5-dimethylphenylcarbamate. Then, the phytotoxicity of 4,8-DHT and its enantiomers toward the seeds germination and seedling growth of the five tested plant species, including lettuce (Latuca sativa, radish (Raphanus sativus, cucumber (Cucumis sativus, onion (Allium cepa, and wheat (Triticum aestivum, were investigated and the results indicated a hormesis at low concentration of 4,8-DHT and its enantiomers, but a retardant effect at high concentration. Between the two enantiomers of 4,8-DHT, the S-(+-isosclerone was more toxic to seeds germination and seedling growth of the five tested plant species than the R-(−-regiolone, and also the phytotoxicity of S-(+-isosclerone varied with different plants. For example, S-(+-isosclerone was the most active to seedling growth of lettuce, indicating that S-(+-isosclerone had specific effects on different organisms. Thus, all of the chirality and concentration of 4,8-DHT, as well as the affected plant species, need to be taken into consideration in the development and utilization of 4,8-DHT.

  14. Phytotoxic potential of celtis australis L. (family ulmaceae) against four crop species

    International Nuclear Information System (INIS)

    Ahmad, I.; Hussain, F.

    2014-01-01

    Bioassays were conducted to test the phytotoxic potential of Celtis australis against Trifolium alexandrinum, Brassica campestris, Triticum aestivum and Lactuca sativa under laboratory condition. Aqueous extracts from twigs and leaves were obtained by soaking 5 and 10g plant material in 100 ml distilled water for 24 and 48hr durations. Aqueous extracts significantly delayed/retarded the germination and reduced the plumule and radicle growth of all the four test species. Generally, extracts soaked for 48h especially 10 gm/100ml were inhibitory than 24h extracts of 5 or 10gm material. Extracts from twigs were inhibitory to germination of wheat while same extracts inhibited the plumule growth of B. campestris. Radicle growth of T. alexandrinum was inhibited more by twig extracts. Hot water extracts from twigs were less inhibitory than leaf extracts. Litter and mulch also significantly delayed the seed germination and retarded the overall growth of seedlings of all test species. The number and length of seminal roots of T. aestivum was suppressed by all aqueous extracts, added litter and mulch. The inhibitory response depended upon the test species, concentration, soaking duration and physiological parameters. The results suggested that Celtis australis has strong phytotoxic potential. (author)

  15. Advanced oxidation of commercial herbicides mixture: experimental design and phytotoxicity evaluation.

    Science.gov (United States)

    López, Alejandro; Coll, Andrea; Lescano, Maia; Zalazar, Cristina

    2017-05-05

    In this work, the suitability of the UV/H 2 O 2 process for commercial herbicides mixture degradation was studied. Glyphosate, the herbicide most widely used in the world, was mixed with other herbicides that have residual activity as 2,4-D and atrazine. Modeling of the process response related to specific operating conditions like initial pH and initial H 2 O 2 to total organic carbon molar ratio was assessed by the response surface methodology (RSM). Results have shown that second-order polynomial regression model could well describe and predict the system behavior within the tested experimental region. It also correctly explained the variability in the experimental data. Experimental values were in good agreement with the modeled ones confirming the significance of the model and highlighting the success of RSM for UV/H 2 O 2 process modeling. Phytotoxicity evolution throughout the photolytic degradation process was checked through germination tests indicating that the phytotoxicity of the herbicides mixture was significantly reduced after the treatment. The end point for the treatment at the operating conditions for maximum TOC conversion was also identified.

  16. Phytotoxicity of water-soluble substances from alfalfa and barley soil extracts on four crop species.

    Science.gov (United States)

    Read, J J; Jensen, E H

    1989-02-01

    Problems associated with continuously planting alfalfa (Medicago saliva L.) or seeding to thicken depleted alfalfa stands may be due to autotoxicity, an intraspecific form of allelopathy. A bioassay approach was utilized to characterize the specificity and chemical nature of phytotoxins in extracts of alfalfa soils as compared to fallow soil or soil where a cereal was the previous crop. In germination chamber experiments, water-soluble substances present in methanol extracts of soil cropped to alfalfa or barley (Hordeum vulgare L.) decreased seedling root length of alfalfa L-720, winter wheat (Triticum aestivum L. Nugaines) and radish (Raphanus sativa L. Crimson Giant). Five days after germination, seedling dry weights of alfalfa and radish in alfalfa soil extracts were lower compared to wheat or red clover (Trifolium pralense L. Kenland). Growth of red clover was not significantly reduced by soil extracts from cropped soil. Extracts of crop residue screened from soil cropped to alfalfa or barley significantly reduced seedling root length; extracts of alfalfa residue caused a greater inhibition of seedling dry weight than extracts of barely residue. A phytotoxic, unidentified substance present in extracts of crop residue screened from alfalfa soil, which inhibited seedling root length of alfalfa, was isolated by thin-layer chromatography (TLC). Residues from a soil cropped continuously to alfalfa for 10 years had the greatest phytotoxic activity.

  17. Screening of Bunium bulbocastanum for antibacterial, antifungal, phytotoxic and haemagglutination activities.

    Science.gov (United States)

    Khan, Ibrar; Ahmad, Haroon; Ali, Nasir; Ahmad, Bashir; Tanoli, Hamid

    2013-07-01

    The current study was aimed at screening the Bunium bulbocastanum for its antibacterial, antifungal, phytotoxic and haemagglutination activities.The crude methanolic extract and n-hexane fraction showed significant (89%) and good activity (61%) against Staphylococcus aureus while the CHCl3fraction was moderately active against S.aureus (53%). Moderate activitywas shown by the EtOAc fraction against B. subtilis (44%). This fraction was inactive against P.aerogenosa and S.aureus. The aqueous fraction showed significant activity against B. subtilis (85%), moderate against S.aureus(34 %) and E. coli (33%)and low activity against P.aerogenosa(29%). Our results for antifungal assay indicated that all the test samples were inactive against all the test fungi. The phytotoxic activity of the plant at 1000 and 100 μg/ml was: crude methanolic extract (53.33 and 46.66%), n-hexane (46.66 and 26.66%), CHCl3 (20 and 6.66%), EtOAc (46.66 and 26.66%) and aqueous (40 and 33.33%). All the test samples (crude methanolic extract and fractions) of B. bulbocastanum were unable to agglutinate RBCs of the human blood indicating that this species lack phytolectins.

  18. In Vitro Phytotoxicity and Antioxidant Activity of Selected Flavonoids

    Directory of Open Access Journals (Sweden)

    Rita Patrizia Aquino

    2012-05-01

    Full Text Available The knowledge of flavonoids involved in plant-plant interactions and their mechanisms of action are poor and, moreover, the structural characteristics required for these biological activities are scarcely known. The objective of this work was to study the possible in vitro phytotoxic effects of 27 flavonoids on the germination and early radical growth of Raphanus sativus L. and Lepidium sativum L., with the aim to evaluate the possible structure/activity relationship. Moreover, the antioxidant activity of the same compounds was also evaluated. Generally, in response to various tested flavonoids, germination was only slightly affected, whereas significant differences were observed in the activity of the various tested flavonoids against radical elongation. DPPH test confirms the antioxidant activity of luteolin, quercetin, catechol, morin, and catechin. The biological activity recorded is discussed in relation to the structure of compounds and their capability to interact with cell structures and physiology. No correlation was found between phytotoxic and antioxidant activities.

  19. The assessment of executive functioning in children

    OpenAIRE

    Henry, L.; Bettenay, C.

    2010-01-01

    Background: Executive functioning is increasingly seen as incorporating several component sub-skills and clinical assessments should reflect this complexity. \\ud \\ud Method: Tools for assessing executive functioning in children are reviewed within five key areas, across verbal and visuospatial abilities, with emphasis on batteries of tests. \\ud \\ud Results: There are many appropriate tests for children, although the choice is more limited for those under the age of 8 years. \\ud \\ud Conclusion...

  20. Executive Information Systems' Multidimensional Models

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available Executive Information Systems are design to improve the quality of strategic level of management in organization through a new type of technology and several techniques for extracting, transforming, processing, integrating and presenting data in such a way that the organizational knowledge filters can easily associate with this data and turn it into information for the organization. These technologies are known as Business Intelligence Tools. But in order to build analytic reports for Executive Information Systems (EIS in an organization we need to design a multidimensional model based on the business model from the organization. This paper presents some multidimensional models that can be used in EIS development and propose a new model that is suitable for strategic business requests.

  1. Hydrophilic compounds in culture filtrates of Fusarium oxysporum f. sp. cubense GCV [01210] induce protection to banana leave toward a main pathogen phytotoxic component

    Directory of Open Access Journals (Sweden)

    Nayanci Portal González

    2014-07-01

    Full Text Available Panama disease caused by Fusarium oxysporum f. sp. cubense (Foc, is among the most important diseases in Musa spp. Foc is a necrotrophic fungus, their phytotoxins play a role in disease development. Previously culture filtrate (FCC 15 days incubation with differential phytotoxic activity against two Musa cultivars was obtained. From this, the main fraction with nonspecific phytotoxic activity against both cultivars was purified. In this study, the biological activity of the aqueous phase and the main phytotoxic fraction purified from organic extract of Fusarium oxysporum f. sp. cubense VCG [01210] Race 1 FCC was determined on banana leaves of cv. `Gros Michel' (susceptible and `FHIA-01' (resistant. Foc FCC phytotoxic effect was confirmed. The aqueous phase showed no phytotoxic activity on both cultivars, while the simultaneous application of the aqueous phase with the main phytotoxic fraction induced a differential response of tissues in susceptible and resistant cultivars evaluated. The results indicated that the compounds present in the aqueous phase are required to induce the protection of leaf tissue against phytotoxic main component of the pathogen. Key words: culture filtrate, Panama disease, resistant, susceptible

  2. Using in situ pore water concentrations to estimate the phytotoxicity of nicosulfuron in soils to corn (Zea mays L.).

    Science.gov (United States)

    Liu, Kailin; Cao, Zhengya; Pan, Xiong; Yu, Yunlong

    2012-08-01

    The phytotoxicity of an herbicide in soil is typically dependent on the soil characteristics. To obtain a comparable value of the concentration that inhibits growth by 50% (IC50), 0.01 M CaCl(2) , excess pore water (EPW) and in situ pore water (IPW) were used to extract the bioavailable fraction of nicosulfuron from five different soils to estimate the nicosulfuron phytotoxicity to corn (Zea mays L.). The results indicated that the phytotoxicity of nicosulfuron in soils to corn depended on the soil type, and the IC50 values calculated based on the amended concentration of nicosulfuron ranged from 0.77 to 9.77 mg/kg among the five tested soils. The range of variation in IC50 values for nicosulfuron was smaller when the concentrations of nicosulfuron extracted with 0.01 M CaCl(2) and EPW were used instead of the amended concentration. No significant difference was observed among the IC50 values calculated from the IPW concentrations of nicosulfuron in the five tested soils, suggesting that the concentration of nicosulfuron in IPW could be used to estimate the phytotoxicity of residual nicosulfuron in soils. Copyright © 2012 SETAC.

  3. Pyrenophoric acid, a phytotoxic sesquiterpenoid penta-2,4-dienoic acid produced by a potential mycoherbicide, Pyrenophora semeniperda

    Science.gov (United States)

    Marco Masi; Susan Meyer; Alessio Cimmino; Anna Andolfi; Antonio Evidente

    2014-01-01

    A new phytotoxic sesquiterpenoid penta-2,4- dienoic acid, named pyrenophoric acid, was isolated from solid wheat seed culture of Pyrenophora semeniperda, a fungal pathogen proposed as a mycoherbicide for biocontrol of cheatgrass (Bromus tectorum) and other annual bromes. These bromes are serious weeds in winter cereals and also on temperate semiarid rangelands....

  4. Temporal variability in Cu speciation, phytotoxicity, and soil microbial activity of Cu-polluted soils as affected by elevated temperature.

    Science.gov (United States)

    Fu, Qing-Long; Weng, Nanyan; Fujii, Manabu; Zhou, Dong-Mei

    2018-03-01

    Global warming has obtained increasing attentions due to its multiple impacts on agro-ecosystem. However, limited efforts had been devoted to reveal the temporal variability of metal speciation and phytotoxicity of heavy metal-polluted soils affected by elevated temperature under the global warming scenario. In this study, effects of elevated temperature (15 °C, 25 °C, and 35 °C) on the physicochemical properties, microbial metabolic activities, and phytotoxicity of three Cu-polluted soils were investigated by a laboratory incubation study. Soil physicochemical properties were observed to be significantly altered by elevated temperature with the degree of temperature effect varying in soil types and incubation time. The Biolog and enzymatic tests demonstrated that soil microbial activities were mainly controlled and decreased with increasing incubation temperature. Moreover, plant assays confirmed that the phytotoxicity and Cu uptake by wheat roots were highly dependent on soil types but less affected by incubation temperature. Overall, the findings in this study have highlighted the importance of soil types to better understand the temperature-dependent alternation of soil properties, Cu speciation and bioavailability, as well as phytotoxicity of Cu-polluted soils under global warming scenario. The present study also suggests the necessary of investigating effects of soil types on the transport and accumulation of toxic elements in soil-crop systems under global warming scenario. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Nitric Oxide Ameliorates Zinc Oxide Nanoparticles Phytotoxicity in Wheat Seedlings: Implication of the Ascorbate–Glutathione Cycle

    Science.gov (United States)

    Tripathi, Durgesh K.; Mishra, Rohit K.; Singh, Swati; Singh, Samiksha; Vishwakarma, Kanchan; Sharma, Shivesh; Singh, Vijay P.; Singh, Prashant K.; Prasad, Sheo M.; Dubey, Nawal K.; Pandey, Avinash C.; Sahi, Shivendra; Chauhan, Devendra K.

    2017-01-01

    The present study investigates ameliorative effects of nitric oxide (NO) against zinc oxide nanoparticles (ZnONPs) phytotoxicity in wheat seedlings. ZnONPs exposure hampered growth of wheat seedlings, which coincided with reduced photosynthetic efficiency (Fv/Fm and qP), due to increased accumulation of zinc (Zn) in xylem and phloem saps. However, SNP supplementation partially mitigated the ZnONPs-mediated toxicity through the modulation of photosynthetic activity and Zn accumulation in xylem and phloem saps. Further, the results reveal that ZnONPs treatments enhanced levels of hydrogen peroxide and lipid peroxidation (as malondialdehyde; MDA) due to severely inhibited activities of the following ascorbate–glutatione cycle (AsA–GSH) enzymes: ascorbate peroxidase, glutathione reductase, monodehydroascorbate reductase and dehydroascorbate reductase, and its associated metabolites ascorbate and glutathione. In contrast to this, the addition of SNP together with ZnONPs maintained the cellular functioning of the AsA–GSH cycle properly, hence lesser damage was noticed in comparison to ZnONPs treatments alone. The protective effect of SNP against ZnONPs toxicity on fresh weight (growth) can be reversed by 2-(4carboxy-2-phenyl)-4,4,5,5-tetramethyl- imidazoline-1-oxyl-3-oxide, a NO scavenger, and thus suggesting that NO released from SNP ameliorates ZnONPs toxicity. Overall, the results of the present study have shown the role of NO in the reducing of ZnONPs toxicity through the regulation of accumulation of Zn as well as the functioning of the AsA–GSH cycle. PMID:28220127

  6. Sediment Resuspension and Deposition on Seagrass Leaves Impedes Internal Plant Aeration and Promotes Phytotoxic H2S Intrusion.

    Science.gov (United States)

    Brodersen, Kasper E; Hammer, Kathrine J; Schrameyer, Verena; Floytrup, Anja; Rasheed, Michael A; Ralph, Peter J; Kühl, Michael; Pedersen, Ole

    2017-01-01

    HIGHLIGHTS: Sedimentation of fine sediment particles onto seagrass leaves severely hampers the plants' performance in both light and darkness, due to inadequate internal plant aeration and intrusion of phytotoxic H 2 S. Anthropogenic activities leading to sediment re-suspension can have adverse effects on adjacent seagrass meadows, owing to reduced light availability and the settling of suspended particles onto seagrass leaves potentially impeding gas exchange with the surrounding water. We used microsensors to determine O 2 fluxes and diffusive boundary layer (DBL) thickness on leaves of the seagrass Zostera muelleri with and without fine sediment particles, and combined these laboratory measurements with in situ microsensor measurements of tissue O 2 and H 2 S concentrations. Net photosynthesis rates in leaves with fine sediment particles were down to ~20% of controls without particles, and the compensation photon irradiance increased from a span of 20-53 to 109-145 μmol photons m -2 s -1 . An ~2.5-fold thicker DBL around leaves with fine sediment particles impeded O 2 influx into the leaves during darkness. In situ leaf meristematic O 2 concentrations of plants exposed to fine sediment particles were lower than in control plants and exhibited long time periods of complete meristematic anoxia during night-time. Insufficient internal aeration resulted in H 2 S intrusion into the leaf meristematic tissues when exposed to sediment resuspension even at relatively high night-time water-column O 2 concentrations. Fine sediment particles that settle on seagrass leaves thus negatively affect internal tissue aeration and thereby the plants' resilience against H 2 S intrusion.

  7. Sediment Resuspension and Deposition on Seagrass Leaves Impedes Internal Plant Aeration and Promotes Phytotoxic H2S Intrusion

    Directory of Open Access Journals (Sweden)

    Kasper E. Brodersen

    2017-05-01

    Full Text Available HIGHLIGHTS:Sedimentation of fine sediment particles onto seagrass leaves severely hampers the plants' performance in both light and darkness, due to inadequate internal plant aeration and intrusion of phytotoxic H2S.Anthropogenic activities leading to sediment re-suspension can have adverse effects on adjacent seagrass meadows, owing to reduced light availability and the settling of suspended particles onto seagrass leaves potentially impeding gas exchange with the surrounding water. We used microsensors to determine O2 fluxes and diffusive boundary layer (DBL thickness on leaves of the seagrass Zostera muelleri with and without fine sediment particles, and combined these laboratory measurements with in situ microsensor measurements of tissue O2 and H2S concentrations. Net photosynthesis rates in leaves with fine sediment particles were down to ~20% of controls without particles, and the compensation photon irradiance increased from a span of 20–53 to 109–145 μmol photons m−2 s−1. An ~2.5-fold thicker DBL around leaves with fine sediment particles impeded O2 influx into the leaves during darkness. In situ leaf meristematic O2 concentrations of plants exposed to fine sediment particles were lower than in control plants and exhibited long time periods of complete meristematic anoxia during night-time. Insufficient internal aeration resulted in H2S intrusion into the leaf meristematic tissues when exposed to sediment resuspension even at relatively high night-time water-column O2 concentrations. Fine sediment particles that settle on seagrass leaves thus negatively affect internal tissue aeration and thereby the plants' resilience against H2S intrusion.

  8. The Executive as Integrator.

    Science.gov (United States)

    Cohn, Hans M.

    1983-01-01

    Argues that although the executive has many tasks, he or she must view internal organizational integration as a primary task, making use of organizational charts, job descriptions, statements of goals and objectives, evaluations, and feedback devices. (RH)

  9. Executive control of attention in narcolepsy.

    Directory of Open Access Journals (Sweden)

    Sophie Bayard

    Full Text Available BACKGROUND: Narcolepsy with cataplexy (NC is a disabling sleep disorder characterized by early loss of hypocretin neurons that project to areas involved in the attention network. We characterized the executive control of attention in drug-free patients with NC to determine whether the executive deficits observed in patients with NC are specific to the disease itself or whether they reflect performance changes due to the severity of excessive daytime sleepiness. METHODOLOGY: Twenty-two patients with NC compared to 22 patients with narcolepsy without cataplexy (NwC matched for age, gender, intellectual level, objective daytime sleepiness and number of sleep onset REM periods (SOREMPs were studied. Thirty-two matched healthy controls were included. All participants underwent a standardized interview, completed questionnaires, and neuropsychological tests. All patients underwent a polysomnography followed by multiple sleep latency tests (MSLT, with neuropsychological evaluation performed the same day between MSLT sessions. PRINCIPAL FINDINGS: Irrespective of diagnosis, patients reported higher self-reported attentional complaints associated with the intensity of depressive symptoms. Patients with NC performed slower and more variably on simple reaction time tasks than patients with NwC, who did not differ from controls. Patients with NC and NwC generally performed slower, reacted more variably, and made more errors than controls on executive functioning tests. Individual profile analyses showed a clear heterogeneity of the severity of executive deficit. This severity was related to objective sleepiness, higher number of SOREMPs on the MSLT, and lower intelligence quotient. The nature and severity of the executive deficits were unrelated to NC and NwC diagnosis. CONCLUSIONS: We demonstrated that drug-free patients with NC and NwC complained of attention deficit, with altered executive control of attention being explained by the severity of objective

  10. WEBSITE EXECUTION OF CAD MODULES

    Directory of Open Access Journals (Sweden)

    A. A. Lyalinsky

    2013-01-01

    Full Text Available Web-based interface of modules that are part of the computer-aided design system in microelectronics is considered. The influence of several factors (available computer  memory, maximum allowed run time, degree of homogeneity of the software on the structure of the created system is investigated. Synchronous and asynchronous variants of interaction between control and executive parts are described. References on the systems that allow an access to applications in CAD microelectronics and are based on the principles discussed in this article are given.

  11. Warhead Monitoring Planning and Execution

    Energy Technology Data Exchange (ETDEWEB)

    Nakae, L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-12-05

    The Warhead Measurement Campaign is a multi-laboratory project lead by the Los Alamos National Laboratory. The project will measure several items of the US nuclear weapons stockpile with a wide range of radiation detection systems. This report provides a brief summary of those LLNL executed activities for the Warhead Measurement Campaign from FY11 through FY16. A more detailed description of all of LLNL’s activiites for the WMC will be presented in the final report of a follow-on project, , LA17-V-Wx.

  12. Effects of sulfur nutrition on phytotoxicity and growth responses of bean plants to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Adedipe, N O; Hofstra, G; Ormrod, D P

    1972-01-01

    Phaseolus vulgaris L. cv. Blue Lake plants were grown in sand culture at three temperatures, and fed with nutrient solution containing 1.3 or 32 mg/liter sulfur (S). Plants were fumigated twice with ozone at 50 parts per hundred million (pphm) for 2 h. Intensity of phytotoxicity was markedly lower in plants grown at the high S rate. Ozone reduced chlorophyll content of plants grown in low S at 25/20 and 30/25/sup 0/. With the high S treatment, however, ozone had no significant effect on chlorophyll content particularly at the lower temperatures. Irrespective of S nutrition, ozone had no effect on total soluble carbohydrate content. Ozone effects on plant growth depended on plant part, growth temperature, and S nutrition.

  13. Phytotoxic effects of aqueous leaf extracts of two eucalyptus SPP. against parthenium hysterophorus L

    International Nuclear Information System (INIS)

    Javaid, A.; Shah, M.B.M.

    2007-01-01

    The present study was carried out to investigate the phytotoxic effect of aqueous leaf extracts of two eucalyptus species viz. E citriodora Hook and E. camaldulensis Dehnh. Against the germination and seeding growth of alien aggressive weed parthenium hysterophorus L. The experiment was conducted in department of Mycology and plant Pathology in 2006. Aqueous leaf extracts of 2, 4, 6, 8 and 10% (w/v) of the two aforementioned Eucalyptus species were employed in the present study. Extracts of 2-8% concentration of both the Eucalyptus species significantly suppressed germination of the target weed species. A 10% extract of both the species completely arrested the germination. Aqueous extracts also reduced the root and shoot length of parthenium. Effect of extracts on seedling biomass was insignificant. (author)

  14. An overview on manufactured nanoparticles in plants: Uptake, translocation, accumulation and phytotoxicity.

    Science.gov (United States)

    Tripathi, Durgesh Kumar; Shweta; Singh, Shweta; Singh, Swati; Pandey, Rishikesh; Singh, Vijay Pratap; Sharma, Nilesh C; Prasad, Sheo Mohan; Dubey, Nawal Kishore; Chauhan, Devendra Kumar

    2017-01-01

    The unprecedented capability to control and characterize materials on the nanometer scale has led to the rapid expansion of nanostructured materials. The expansion of nanotechnology, resulting into myriads of consumer and industrial products, causes a concern among the scientific community regarding risk associated with the release of nanomaterials in the environment. Bioavailability of excess nanomaterials ultimately threatens ecosystem and human health. Over the past few years, the field of nanotoxicology dealing with adverse effects and the probable risk associated with particulate structures ways of phytotoxicity on morpho-anatomical, physiological, biochemical and molecular traits of plants. Besides this, the present review also examines the intrinsic detoxification mechanisms in plants in light of nanomaterial accumulation within plant cells or parts. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  15. Synthesis and phytotoxicity of 4,5 functionalized tetrahydrofuran-2-ones

    Energy Technology Data Exchange (ETDEWEB)

    Resende, Gabriela C.; Alvarenga, Elson S., E-mail: elson@ufv.br [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Quimica; Galindo, Juan C.G.; Macias, Francisco A. [Grupo de Alelopatia, Departamento de Quimica Organica, Facultad de Ciencias, Universidad de Cadiz (Spain)

    2012-12-15

    In this work we report a versatile synthesis of fourteen {gamma}-lactones all structurally related, nine of which are novel compounds, accomplished from the readily available furfural. The phytotoxic activity of the synthesized compounds was evaluated in vitro by the influence on the growth of heat coleoptiles. The percentages of inhibition were mostly small and not statistically different from control after the third dilution (100 Greek-Small-Letter-Mu mol L{sup -1}). In general, {alpha},{beta}-unsaturated lactones presented better activities than the saturated ones. The most active compounds presented 51, 68 and 76% of inhibition in 1000 Greek-Small-Letter-Mu mol L-1. The results indicate that regardless of saturation, the presence of the {gamma}-lactone moiety is important for the bioactivity, but their presence has no implications with potency. (author)

  16. Orthophosphate modulates the phytotoxicity of nano-ZnO to Lemna minor (L.).

    Science.gov (United States)

    Chen, Xiaolin; O'Halloran, John; Jansen, Marcel A K

    2018-03-02

    Because of their applications in large numbers of products, Zinc Oxide nanoparticles (nano-ZnO) will inevitably enter into the environment. Nano-ZnO released into the environment will be present in a complex matrix which can cause various chemical and physical transformations and modulate the biological reactivity of these particles. Due to their rapid growth and small size, Lemna minor is recommended by OECD for toxicological testing. Here, we tested how nano-ZnO reactivity is modulated by the suite of macro- and micronutrients that are present in Lemna minor growth media. Specifically, we measured ex situ Reactive Oxygen Species (ROS) formation by nano-ZnO, and subsequent in planta toxicity. The data show how orthophosphate can modulate both ex situ ROS formation, and in planta toxicity. This has ramifications for phytotoxicity testing, which is commonly performed under controlled conditions and on media containing orthophosphate.

  17. Chemical basis for the phytotoxicity of N-aryl hydroxamic acids and acetanilide analogues.

    Science.gov (United States)

    Bravo, Héctor R; Villarroel, Elisa; Copaja, Sylvia V; Argandoña, Victor H

    2008-01-01

    Germination inhibition activity of N-aryl hydroxamic acids and acetanilide analogues was measured on lettuce seeds (Lactuca sativa). Lipophilicity of the compounds was determined by HPLC. A correlation between lipophilicity values and percentage of germination inhibition was established. A model mechanism of action for auxin was used for analyzing the effect of the substituent at the alpha carbon atom (Ca) on the polarization of hydroxamic and amide functions in relation to the germination inhibition activity observed. Results suggest that the lipophilic and acidic properties play an important role in the phytotoxicity of the compounds. A test with the microalga Chlorella vulgaris was used to evaluate the potential herbicide activity of the hydroxamic acids and acetanilides.

  18. Contribution of a phytotoxic compound to the allelopathy of Ginkgo biloba.

    Science.gov (United States)

    Kato-Noguchi, Hisashi; Takeshita, Sayaka

    2013-11-01

    Ginkgo (Ginkgo biloba L.) has not changed over 121 million years. There may be unknown special strategy for the survival. Gingko litter inhibited the growth of weed species ryegrass (Lolium multiflorum L.). The inhibition was greater with the litter of the close position than that of the far position from the gingko tree. A phytotoxic substance, 2-hydroxy-6-(10-hydroxypentadec-11-enyl)benzoic acid (HHPEBA) was isolated in the litter. HHPEBA concentration was greater in the litter of the close position than that of the far position from the tree. HHPEBA inhibited the ryegrass growth at concentrations greater than 3 μM. HHPEBA was estimated to be able to cause 47-62% of the observed growth inhibition of ryegrass by the gingko litter. Therefore, HHPEBA may contribute to the inhibitory effect caused by ginkgo litter and may provide a competitive advantage for gingko to survive through the growth inhibition of the neighboring plants.

  19. A miniature bioassay for testing the acute phytotoxicity of photosystem II herbicides on seagrass.

    Directory of Open Access Journals (Sweden)

    Adam D Wilkinson

    Full Text Available Photosystem II (PSII herbicides have been detected in nearshore tropical waters such as those of the Great Barrier Reef and may add to the pressure posed by runoff containing sediments and nutrients to threatened seagrass habitats. There is a growing number of studies into the potential effects of herbicides on seagrass, generally using large experimental setups with potted plants. Here we describe the successful development of an acute 12-well plate phytotoxicity assay for the PSII herbicide Diuron using isolated Halophila ovalis leaves. Fluorescence images demonstrated Diuron affected the entire leaf surface evenly and responses were not influenced by isolating leaves from the plant. The optimum exposure duration was 24 h, by which time the inhibition of effective quantum yield of PSII (∆F/F(m' was highest and no deterioration of photosystems was evident in control leaves. The inhibition of ∆F/F(m' by Diuron in isolated H. ovalis leaves was identical to both potted and hydroponically grown plants (with leaves remaining attached to rhizomes, indicating similar reductions in photosynthetic activity in these acute well-plate assays. The sensitivity of the assay was not influenced by irradiance (range tested 40 to 400 μmol photons m(-2 s(-1. High irradiance, however, caused photo-oxidative stress in H. ovalis and this generally impacted in an additive or sub-additive way with Diuron to damage PSII. The bioassay using isolated leaves is more rapid, uses far less biological material and does not rely on specialised aquarium facilities in comparison with assays using potted plants. The development and validation of this sensitive bioassay will be useful to reliably screen and monitor the phytotoxicity of existing and emerging PSII herbicides and contribute to risk assessments and water quality guideline development in the future.

  20. A Miniature Bioassay for Testing the Acute Phytotoxicity of Photosystem II Herbicides on Seagrass

    Science.gov (United States)

    Wilkinson, Adam D.; Collier, Catherine J.; Flores, Florita; Mercurio, Phil; O’Brien, Jake; Ralph, Peter J.; Negri, Andrew P.

    2015-01-01

    Photosystem II (PSII) herbicides have been detected in nearshore tropical waters such as those of the Great Barrier Reef and may add to the pressure posed by runoff containing sediments and nutrients to threatened seagrass habitats. There is a growing number of studies into the potential effects of herbicides on seagrass, generally using large experimental setups with potted plants. Here we describe the successful development of an acute 12-well plate phytotoxicity assay for the PSII herbicide Diuron using isolated Halophila ovalis leaves. Fluorescence images demonstrated Diuron affected the entire leaf surface evenly and responses were not influenced by isolating leaves from the plant. The optimum exposure duration was 24 h, by which time the inhibition of effective quantum yield of PSII (∆F/Fm’) was highest and no deterioration of photosystems was evident in control leaves. The inhibition of ∆F/Fm’ by Diuron in isolated H. ovalis leaves was identical to both potted and hydroponically grown plants (with leaves remaining attached to rhizomes), indicating similar reductions in photosynthetic activity in these acute well-plate assays. The sensitivity of the assay was not influenced by irradiance (range tested 40 to 400 μmol photons m-2 s-1). High irradiance, however, caused photo-oxidative stress in H. ovalis and this generally impacted in an additive or sub-additive way with Diuron to damage PSII. The bioassay using isolated leaves is more rapid, uses far less biological material and does not rely on specialised aquarium facilities in comparison with assays using potted plants. The development and validation of this sensitive bioassay will be useful to reliably screen and monitor the phytotoxicity of existing and emerging PSII herbicides and contribute to risk assessments and water quality guideline development in the future. PMID:25674791

  1. Regional differences in plant levels and investigations on the phytotoxicity of lithium.

    Science.gov (United States)

    Franzaring, Jürgen; Schlosser, Sonja; Damsohn, Walter; Fangmeier, Andreas

    2016-09-01

    The growing use of lithium (Li) in industrial and energetic applications and the inability to completely recycle the alkali metal will most likely increase anthropogenic emissions and environmental concentrations in the future. Although non-essential to plants, Li(+) is an important ultra-trace element in the animal and human diet and is also used in the treatment of e.g. mental disorders. Most of the lithium is consumed with the drinking water and vegetables, but concentrations in foodstuffs vary with the geochemistry of the element. In order to identify potential risks and to avoid an overmedication due to consumption of Li rich or Li contaminated foods it is advisable to identify background levels and to derive recommended Daily Allowances (RDAs) for the element. Although Germany does not possess large amounts of primary or secondary resources of lithium, geochemical investigations (mineral and ground waters and soils) in this country confirm a wide variation of environmental concentrations with generally higher levels in the southwest. Despite the large number of soil and water data, only very few data exist on lithium concentrations in plants and its phytotoxicity. Within the scope of present study common grassland plant species were sampled in regions of SW-Germany with reportedly high geogenic levels of Li. The data are discussed with regard to literature surveys and existing reference values. Since lithium has phytotoxic effects a greenhouse experiment was performed with different Li salts (LiCl and Li2CO3) and plant species (maize, bean and buckwheat) to derive dose-response relationships for the endpoint shoot growth. While corn growth was not reduced significantly by soil concentrations of 118 ppm, EC50 values in buckwheat were 47 and 16 ppm for lithium derived from LiCl and Li2CO3, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Phytotoxic activity and chemical composition of aqueous volatile fractions from Eucalyptus species.

    Directory of Open Access Journals (Sweden)

    Jinbiao Zhang

    Full Text Available The essential oils from four Eucalyptus species (E. spathulata, E. salubris, E. brockwayii and E. dundasii have been previously confirmed to have stronger inhibitory effects on germination and seedling growth of silverleaf nightshade (Solanum elaeagnifolium Cav.. The aqueous volatile fractions (AVFs were the water soluble volatile fractions produced together with the essential oils (water insoluble fractions during the steam distillation process. The aim of this study was to further assess the phytotoxicity of AVFs from the four Eucalyptus species and their chemical composition. The fresh leaves of the four Eucalyptus species were used for the extraction of AVFs. The AVFs were tested for their phytotoxic effects on the perennial weed, silverleaf nightshade under laboratory conditions. The chemical compositions of the AVFs were determined by gas chromatograph-mass spectrometry (GC-MS. Our results showed that the AVFs had strong inhibition on the germination and seedling growth of silverleaf nightshade. The inhibition index increased with the increasing concentrations of AVFs. The inhibitory effects of the AVFs varied between different Eucalyptus species. The AVF from E. salubris demonstrated the highest inhibitory activity on the weed tested, with complete inhibition on germination and seedling growth at a concentration of 75%. The GC-MS analysis revealed that 1,8-cineole, isopentyl isovalerate, isomenthol, pinocarvone, trans-pinocarveol, alpha-terpineol and globulol were the main compounds in the AVFs. These results indicated that all AVFs tested had differential inhibition on the germination and seedling growth of silverleaf nightshade, which could be due to the joint effects of compounds present in the AVFs as these compounds were present in different quantities and ratio between Eucalyptus species.

  3. Phytotoxic Activity and Chemical Composition of Aqueous Volatile Fractions from Eucalyptus Species

    Science.gov (United States)

    Zhang, Jinbiao; An, Min; Wu, Hanwen; Liu, De Li; Stanton, Rex

    2014-01-01

    The essential oils from four Eucalyptus species (E. spathulata, E. salubris, E. brockwayii and E. dundasii) have been previously confirmed to have stronger inhibitory effects on germination and seedling growth of silverleaf nightshade (Solanum elaeagnifolium Cav.). The aqueous volatile fractions (AVFs) were the water soluble volatile fractions produced together with the essential oils (water insoluble fractions) during the steam distillation process. The aim of this study was to further assess the phytotoxicity of AVFs from the four Eucalyptus species and their chemical composition. The fresh leaves of the four Eucalyptus species were used for the extraction of AVFs. The AVFs were tested for their phytotoxic effects on the perennial weed, silverleaf nightshade under laboratory conditions. The chemical compositions of the AVFs were determined by gas chromatograph–mass spectrometry (GC-MS). Our results showed that the AVFs had strong inhibition on the germination and seedling growth of silverleaf nightshade. The inhibition index increased with the increasing concentrations of AVFs. The inhibitory effects of the AVFs varied between different Eucalyptus species. The AVF from E. salubris demonstrated the highest inhibitory activity on the weed tested, with complete inhibition on germination and seedling growth at a concentration of 75%. The GC-MS analysis revealed that 1,8-cineole, isopentyl isovalerate, isomenthol, pinocarvone, trans-pinocarveol, alpha-terpineol and globulol were the main compounds in the AVFs. These results indicated that all AVFs tested had differential inhibition on the germination and seedling growth of silverleaf nightshade, which could be due to the joint effects of compounds present in the AVFs as these compounds were present in different quantities and ratio between Eucalyptus species. PMID:24681490

  4. Chaetoglobosins from Chaetomium globosum, an endophytic fungus in Ginkgo biloba, and their phytotoxic and cytotoxic activities.

    Science.gov (United States)

    Li, He; Xiao, Jian; Gao, Yu-Qi; Tang, Jiang Jiang; Zhang, An-Ling; Gao, Jin-Ming

    2014-04-30

    In preceding studies, cultivation of Chaetomium globosum, an endophytic fungus in Ginkgo biloba, produced five cytochalasan mycotoxins, chaetoglobosins A, G, V, Vb, and C (1-5), in three media. In the present work, five known chaetoglobosins, C, E, F, Fex, and 20-dihydrochaetoglobosin A (5-9), together with the four known compounds (11-14), were isolated from the MeOH extracts of the solid culture of the same endophyte. The structures of these metabolites were elucidated on the basis of spectroscopic analysis. Treatment of chaetoglobosin F (7) with (diethylamino)sulfur trifluoride (DAST) in dichloromethane afforded an unexpected fluorinated chaetoglobosin, named chaetoglobosin Fa (10), containing an oxolane ring between C-20 and C-23. The phytotoxic effects of compounds 1, 3-8, and 10 were assayed on radish seedlings; some of these compounds (1, 3, and 6-8) significantly inhibited the growth of radish (Raphanus sativus) seedlings with inhibitory rates of >60% at a concentration of 50 ppm, which was comparable or superior to the positive control, glyphosate. In addition, the cytotoxic activities against HCT116 human colon cancer cells were also tested, and compounds 1 and 8-10 showed remarkable cytotoxicity with IC50 values ranging from 3.15 to 8.44 μM, in comparison to the positive drug etoposide (IC50 = 2.13 μM). The epoxide ring between C-6 and C-7 or the double bond at C-6(12) led to a drastically increased cytotoxicity, and chaetoglobosin Fa (10) displayed a markedly increased cytotoxicity but decreased phytotoxicity.

  5. Quaternary ammonium salts with tetrafluoroborate anion: Phytotoxicity and oxidative stress in terrestrial plants

    Energy Technology Data Exchange (ETDEWEB)

    Biczak, Robert, E-mail: r.biczak@ajd.czest.pl

    2016-03-05

    Highlights: • The level of oxidative stress in mono- and dicotyledonous plants was comparable. • Chlorophyll content in the plants was correlated with QAS concentration in the soil. • POD activity increased in plants cultivated in soil with high QAS content. - Abstract: This paper discusses the impact of four quaternary ammonium salts (QAS) such as tetraethylammonium tetrafluoroborate [TEA][BF{sub 4}], tetrabutylammonium tetrafluoroborate [TBA][BF{sub 4}], tetrahexylammonium tetrafluoroborate [THA][BF{sub 4}], and tetraoctylammonium tetrafluoroborate [TOA][BF{sub 4}] on the growth and development of spring barley and common radish. Analogous tests were performed with the inorganic salt ammonium tetrafluoroborate [A][BF{sub 4}] for comparison purposes. Results indicated that the phytotoxicity of the QAS applied is dependent on the concentration of the substance and their number of carbon atoms. The most toxic compound was [TBA][BF{sub 4}], causing the greatest drop in fresh weight of both study plants, similar to the phytotoxic effects of [A][BF{sub 4}]. All the tested compounds caused oxidative stress in spring barley and common radish seedlings due to a drop in the chlorophyll content. Stress was also observed in plants, which was indicated by the increased level of ROS (reactive oxygen species) such as H{sub 2}O{sub 2} and lipid peroxidation of MDA (malondialdehyde). Due to the stress, both plants displayed changes in the activity of antioxidative enzymes such as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD). Based on the results of the study, it was concluded that changes in chlorophyll levels and peroxidase activity are the best biomarkers to determine oxidative stress in plants.

  6. Educating Executive Function

    Science.gov (United States)

    Blair, Clancy

    2016-01-01

    Executive functions are thinking skills that assist with reasoning, planning, problem solving, and managing one’s life. The brain areas that underlie these skills are interconnected with and influenced by activity in many different brain areas, some of which are associated with emotion and stress. One consequence of the stress-specific connections is that executive functions, which help us to organize our thinking, tend to be disrupted when stimulation is too high and we are stressed out, or too low when we are bored and lethargic. Given their central role in reasoning and also in managing stress and emotion, scientists have conducted studies, primarily with adults, to determine whether executive functions can be improved by training. By and large, results have shown that they can be, in part through computer-based videogame-like activities. Evidence of wider, more general benefits from such computer-based training, however, is mixed. Accordingly, scientists have reasoned that training will have wider benefits if it is implemented early, with very young children as the neural circuitry of executive functions is developing, and that it will be most effective if embedded in children’s everyday activities. Evidence produced by this research, however, is also mixed. In sum, much remains to be learned about executive function training. Without question, however, continued research on this important topic will yield valuable information about cognitive development. PMID:27906522

  7. Evaluation of phytotoxicity effect of olive mill wastewater treated by different technologies on seed germination of barley (Hordeum vulgare L.).

    Science.gov (United States)

    Rusan, Munir J M; Albalasmeh, Ammar A; Zuraiqi, Said; Bashabsheh, Mohammad

    2015-06-01

    Olive-mill wastewater (OMW) is a by-product effluent of olive oil extraction process that is produced in large amount in the Mediterranean region. OMW is believed to induce phytotoxic effect on organisms including seed germination and plant growth. The objective of this study was to evaluate the impact of untreated and treated OMW with different techniques on seed germination of barley (Hordeum vulgare L.). The following treatments were investigated: (1) tap water (control); (2) OMW treated by aerobic biological technology in a Jacto Reactor (JR); (3) OMW treated by solar fenton oxidation (SFO); (4) OMW treated by microfiltration followed by nanofiltration (MF+NF); (5) OMW treated by microfiltration followed by reverse osmosis (MF+RO) process; (6) diluted OMW with tap water (25 % OMW); (7) diluted OMW with tap water (50 % OMW); (8) diluted OMW with tap water (75 % OMW); and (9) untreated OMW (100 % OMW). A germination test was conducted in an incubator at temperature of 23 (∘)C. In each petri dish, a filter paper was mounted and ten seeds of barley were placed on the filter paper. Five milliliter of water were added to each petri dish. The seed germination was determined by counting the number of germinated seeds to calculate the percentage of germination (G %). Germination rate index (GRI), seed vigor index (SVI), and phytotoxicity index (PI) were also calculated. Then, the dry weights and lengths of the shoots and the roots of the germinated seeds were measured. The results show that 100, 75, and 50 %OMW were very phytotoxic and completely prohibited seed germination. However, phytotoxicity decreased significantly following treatments of OMW with all techniques investigated and by the 25 % OMW dilution, as results of removing the phenols and other phytotoxic organic compounds from the OMW or by diluting it. This was evidenced by relative enhancement of the dry weights and lengths of shoot and root as well as the G %, GRI, SVG, and PI. It was concluded that if

  8. MIV Project: Executive Summary

    DEFF Research Database (Denmark)

    Ravazzotti, Mariolina T.; Jørgensen, John Leif; Neefs, Marc

    1997-01-01

    Under the ESA contract #11453/95/NL/JG(SC), aiming at assessing the feasibility of Rendez-vous and docking of unmanned spacecrafts, a reference mission scenario was defined. This report gives an executive summary of the achievements and results from the project.......Under the ESA contract #11453/95/NL/JG(SC), aiming at assessing the feasibility of Rendez-vous and docking of unmanned spacecrafts, a reference mission scenario was defined. This report gives an executive summary of the achievements and results from the project....

  9. Phytotoxicity of brominated diphenyl ether-47 (BDE-47) and its hydroxylated and methoxylated analogues (6-OH-BDE-47 and 6-MeO-BDE-47) to maize (Zea mays L.).

    Science.gov (United States)

    Xu, Xuehui; Huang, Honglin; Wen, Bei; Wang, Sen; Zhang, Shuzhen

    2015-03-16

    Polybrominated diphenyl ethers (PBDEs), methoxylated PBDEs (MeO-PBDEs), and hydroxylated PBDEs (OH-PBDEs) are widely found in various environmental media, which is of concern given their biological toxicity. In this study, the phytotoxicities of BDE-47, 6-MeO-BDE-47, and 6-OH-BDE-47 to maize (Zea mays L.) were investigated by an in vivo exposure experiment. Results showed that BDE-47, 6-MeO-BDE-47, and 6-OH-BDE-47 inhibited seed germination and seedling development, and elevated malondialdehyde (MDA), carbonyl groups, and phosphorylated histone H2AX levels in maize roots, suggesting the inducement of lipid peroxidation, protein carbonylation, and DNA damage to maize. Exposure to BDE-47, 6-MeO-BDE-47, and 6-OH-BDE-47 caused the overproduction of H2O2, O2(•-), and •OH, and elevated the activities of antioxidant enzymes in the roots. In addition, 6-OH-BDE-47 caused more severe damage and reactive oxygen species (ROS) generation in maize than did BDE-47 and 6-MeO-BDE-47. These results demonstrated the phytotoxicities of BDE-47, 6-OH-BDE-47, and 6-MeO-BDE-47 to maize, and clarified that overproduction of ROS was the key mechanism leading to toxicity. This study offers useful information for a more comprehensive understanding of the environmental behaviors and toxicities of PBDEs, MeO-PBDEs, and OH-PBDEs.

  10. Executions in The Bahamas

    Directory of Open Access Journals (Sweden)

    Lofquist, William Steele

    2010-01-01

    Full Text Available The stories of those who have been executed in the Bahamas are heretofore untold. In telling these stories and in linking them to the changing course of Bahamian history, the present research adds an important dimension to our understanding of Bahamian history and politics. The major theme of this effort is that the changing practice of the death penalty is much more than a consequence of changes in crime. The use of the death penalty parallels the changing interests of colonial rulers, the changing practice of slavery, and the changing role of the Bahamas in colonial and regional affairs. Four distinctive eras of death penalty practice can be identified: (1 the slave era, where executions and commutations were used liberally and with a clear racial patterning; (2 a long era of stable colonialism, a period of marginalization and few executions; (3 an era of unstable colonialism characterized by intensive and efficient use of the death penalty; and (4 the current independence era of high murder rates and equally high impediments to the use of executions.

  11. Executive functions in synesthesia

    NARCIS (Netherlands)

    Rouw, Romke; van Driel, Joram; Knip, Koen; Richard Ridderinkhof, K.

    2013-01-01

    In grapheme-color synesthesia, a number or letter can evoke two different and possibly conflicting (real and synesthetic) color sensations at the same time. In this study, we investigate the relationship between synesthesia and executive control functions. First, no general skill differences were

  12. School Executive Website Study

    Science.gov (United States)

    Thiede, Robert

    2009-01-01

    The School Executive Website will be a one-stop, online site for officials who are looking for educational data, best practices, product reviews, school documents, professional opinions, and/or job-related networking. The format of the website is designed in certain sections similar to other current and popular websites, such as Angie's List.com,…

  13. EXECUTIVE FUNCTIONING IN SCHIZOPHRENIA

    Directory of Open Access Journals (Sweden)

    Gricel eOrellana

    2013-06-01

    Full Text Available The executive function (EF is a set of abilities, which allows us to invoke voluntary control of our behavioral responses. These functions enable human beings to develop and carry out plans, make up analogies, obey social rules, solve problems, adapt to unexpected circumstances, do many tasks simultaneously and locate episodes in time and place. EF includes divided attention and sustained attention, working memory, set-shifting, flexibility, planning and the regulation of goal directed behavior and can be defined as a brain function underlying the human faculty to act or think not only in reaction to external events but also in relation with internal goals and states. EF is mostly associated with dorsolateral prefrontal cortex (PFC. Besides EF, PFC is involved in self-regulation of behavior, i.e. the ability to regulate behavior according to internal goals and constraints, particularly in less structured situations. Self-regulation of behavior is subtended by ventral medial /orbital PFC. Impairment of EF is one of the most commonly observed deficits in schizophrenia through the various disease stages. Impairment in tasks measuring conceptualization, planning, cognitive flexibility, verbal fluency, ability to solve complex problems and working memory occur in schizophrenia. Disorders detected by executive tests are consistent with evidence from functional neuroimaging, which have shown PFC dysfunction in patients while performing these kinds of tasks. Schizophrenics also exhibit deficit in odor identifying, decision-making and self-regulation of behavior suggesting dysfunction of the orbital PFC. However, impairment in executive tests is explained by dysfunction of prefronto-striato-thalamic, prefronto-parietal and prefronto-temporal neural networks mainly. Disorders in executive functions may be considered central facts with respect to schizophrenia and it has been suggested that negative symptoms may be explained by that executive dysfunction.

  14. Educating executive function.

    Science.gov (United States)

    Blair, Clancy

    2017-01-01

    Executive functions are thinking skills that assist with reasoning, planning, problem solving, and managing one's life. The brain areas that underlie these skills are interconnected with and influenced by activity in many different brain areas, some of which are associated with emotion and stress. One consequence of the stress-specific connections is that executive functions, which help us to organize our thinking, tend to be disrupted when stimulation is too high and we are stressed out, or too low when we are bored and lethargic. Given their central role in reasoning and also in managing stress and emotion, scientists have conducted studies, primarily with adults, to determine whether executive functions can be improved by training. By and large, results have shown that they can be, in part through computer-based videogame-like activities. Evidence of wider, more general benefits from such computer-based training, however, is mixed. Accordingly, scientists have reasoned that training will have wider benefits if it is implemented early, with very young children as the neural circuitry of executive functions is developing, and that it will be most effective if embedded in children's everyday activities. Evidence produced by this research, however, is also mixed. In sum, much remains to be learned about executive function training. Without question, however, continued research on this important topic will yield valuable information about cognitive development. WIREs Cogn Sci 2017, 8:e1403. doi: 10.1002/wcs.1403 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.

  15. Phytotoxic effects of calotropis procera, tamarix aphylla and peganum harmala on plant growth of wheat and mustard

    International Nuclear Information System (INIS)

    Aslam, M.M.; Khatoon, A.; Rehman, A.; Khan, P.; Shakir, S.U.K.; Irfan, S.; Rehman, S.U.; Jamil, M.; Mlaook, I.; Bashar, K.U.; Afridi, M.; Rahim, A.; Ullah, F.

    2016-01-01

    Phytotoxic effects of many plants are known on growth of different useful crops. This research study was designed to find out phytotoxic effects of Calotropis procera, Tamarix aphylla and Peganum harmala on seed germination and seedling length of wheat and mustard. Results showed that seed germination of wheat was significantly decreased by 5 percent, 10 percent, 15 percent, 20 percent and 25 percent while mustard seeds were resistant and were affected by higher dilutions (15 percent, 20 percent and 25 percent) of all plant extracts. Roots of both wheat and mustard were highly affected by plant aqueous extracts at all concentrations (5 percent, 10 percent, 15 percent, 20 percent and 25 percent) but shoots were inhibited by higher concentrations (20 percent and 25 percent). This study revealed that wheat is more sensitive to different plant extracts as compared to mustard. It is thus concluded that inhibitory effect increases with the increase of extracts concentration. (author)

  16. Allelopathic potential of Artemisia arborescens: isolation, identification and quantification of phytotoxic compounds through fractionation-guided bioassays.

    Science.gov (United States)

    Araniti, Fabrizio; Lupini, Antonio; Sorgonà, Agostino; Conforti, Filomena; Marrelli, Mariangela; Statti, Giancarlo Antonio; Menichini, Francesco; Abenavoli, Maria Rosa

    2013-01-01

    The aerial part of Artemisia arborescens L. (Asteraceae) was extracted with water and methanol, and both extracts were fractionated using n-hexane, chloroform, ethyl acetate and n-butanol. The potential phytotoxicity of both crude extracts and their fractions were assayed in vitro on seed germination and root growth of lettuce (Lactuca sativa L.), a sensitive species largely employed in the allelopathy studies. The inhibitory activities were analysed by dose-response curves and the ED 50 were estimated. Crude extracts strongly inhibited both germination and root growth processes. The fraction-bioassay indicated the following hierarchy of phytotoxicity for both physiological processes: ethyl acetate ≥ n-hexane > chloroform ≥ n-butanol. On the n-hexane fraction, GC-MS analyses were carried out to characterise and quantify some of the potential allelochemicals. Twenty-one compounds were identified and three of them, camphor, trans-caryophyllene and pulegone were quantified.

  17. Phytotoxic effects of bottom sediments from Ignalina NPP wastewater canals and cooler

    International Nuclear Information System (INIS)

    Montvydiene, D.

    2002-01-01

    In the paper impact of Ignalina Nuclear Power Plant (INPP) waste upon phytotoxicity of sediments from Lake Drukshiai was recognized. Samples of bottom sediments were collected from various wastewater canals of INPP, from the canal of wastewater treatment plant (WWTP), small lake and rivulet, which are on the route of that wastes into Drukshiai. In 1995, 132 sites of Drukshiai were observed in order to assess the phytotoxicity of its bottom sediments. The research was carried out in July of 1993-2000. Number of somatic mutations (pink, colourless and morphological) and nonviable stamen hairs (the quantity of whose indicates lethality, when hair contains less than 12 cells) in Tradescantia (clone 02) stamen hair (SH) system was counted. Genotoxic effect of bottom sediments on Tradescantia was estimated according to Sparrow et al. (1972) and Marciulioniene et al. (1996). Genotoxic effects were considered weak if amount of somatic mutations not exceeded 1%, there were no non-viable stamen hairs, and medium effect was when the number of somatic mutations was between 1.0-4.0% and non-viable stamen hairs did not reach 40,0%. As well as strong effect was when numbers of somatic mutations and non-viable stamen hairs exceeding 4.0% and 40.0%, respectively. L. sativum is a rather sensitive, widely applied biotest because of its simplicity, cheapness and short duration. This test based on Magone (1989) method and lasted for 48 hours, after which time the seeds germination and root length of seedlings was measured. Tested bottom sediments causing percent inhibitions of 100-60%, 61-40%, 41-20%, and 20-0% were classified as highly toxic, moderately toxic, slightly toxic and non-toxic, respectively. Estimations in both cases were run in triplicates. The data were estimated using the analysis of variance with significance defined at α = 0,05. It was established that in accordance with the phytotoxic impact, the wastes discharged by INPP into Drukshiai in 1993-2000 are attributed

  18. A novel isoindoline, porritoxin sulfonic acid, from Alternaria porri and the structure-phytotoxicity correlation of its related compounds.

    Science.gov (United States)

    Horiuchi, Masayuki; Ohnishi, Keiichiro; Iwase, Noriyasu; Nakajima, Yoshikazu; Tounai, Kenji; Yamashita, Masakazu; Yamada, Yasumasa

    2003-07-01

    Novel zinniol-related compound 3, named porritoxin sulfonic acid, with an isoindoline skeleton was isolated from the culture liquid of Alternaria porri. The structure was determined to be 2-(2"-sulfoethyl)-4-methoxy-5-methyl-6-(3'-methyl-2'-butenyloxy)-2,3-dihydro-1H-isoindol-1-one. The phytotoxic activities of three isoindolines (1-3) were evaluated in a seedling-growth assay against stone leek and lettuce.

  19. Phytotoxicity evaluation of five pharmaceutical pollutants detected in surface water on germination and growth of cultivated and spontaneous plants.

    Science.gov (United States)

    D'Abrosca, Brigida; Fiorentino, Antonio; Izzo, Angelina; Cefarelli, Giuseppe; Pascarella, Maria Teresa; Uzzo, Piera; Monaco, Pietro

    2008-02-15

    The phytotoxicity of 5 pharmaceuticals detected in Italian rivers, atorvastatin (7-[2-(4-fluorophenyl)-3-phenyl-4-(phenylcarbamoyl)-5-propan-2-yl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid), gemfibrozil (5-(2,5-dimethylphenoxy)-2,2-dimethyl-pentanoic acid), tamoxifene (2-[4-(1,2-diphenylbut-1-enyl)phenoxy]-N,N-dimethyl-ethanamine), ethinyl estradiol (17-ethynyl-13-methyl-7,8,9,11, 12,13,14,15,16,17-decahydro-6H-cyclopenta[a]phenanthrene-3,17-diol) and sildenafil (methyl-9-propyl-2,4,7,8-tetrazabicyclo[4.3.0] nona-3,8,10-trien-5-one), has been assessed in a laboratory model. The treatment system consists of three main successive sections. The first one includes the phytotoxic evaluation of the single compounds on crops, Lactuca sativa (lettuce), Dacus carota subsp. sativa (carrot), and Lycopersicon esculentum (tomato), until the 10(-9) M, concentration lower then the environmental amounts. The second section includes the phytotoxicity assessment of all the selected chemicals on wild species, Avena fatua (wild oats), Amaranthus retroflexus (redroot pigweed), Lolium perenne (perennial ryegrass), Taraxacum officinale (common dandelion), and Chenopodium album (lambsquarter), at the same concentration as previously used. The third section of the procedure includes the evaluation of the effects of the five pharmaceuticals, at 1 microM and 1 nM environmental concentrations, on the metabolism of L. sativa. The variation of the composition of the photosynthetic pigments, sugars, lipids, phenols, fatty acids and flavonoids in lettuce seedlings exposed to the pollutants in respect to the blank was evaluated. The results of the phytotoxicity assays showed the possibility of a notable impact on the different vegetal communities and evidenced different sensitivity among cultivated and wild species, probably due to the different plant physiology.

  20. Phytotoxicity of Alachlor, Bromacil and Diuron as single or mixed herbicides applied to wheat, melon, and molokhia.

    Science.gov (United States)

    El-Nahhal, Yasser; Hamdona, Nisreen

    2015-01-01

    This study investigated the phytotoxicity of herbicides applied singly or as mixtures to different crops under greenhouse conditions. Growth inhibition of the crops was taken as an indicator of phytotoxicity. Phytotoxicity of mixtures was estimated by calculating EC50 value in toxic units. EC50 (mg/kg soil) of Alachlor, Bromacil and/or Diuron were: 11.37, 4.77, 1.64, respectively, on melon; 0.11, 0.08, 0.24, respectively, on molokhia, and 3.91, 3.08, 1.83, respectively, on wheat. EC50 values of binary mixture tests of (Alachlor + Bromacil), (Alachlor + Diuron), and (Bromacil + Diuron) were 12.21, 5.84, 10.22 on melon, 0.982, 925.4, 38.1 on molokhia, and 0.673, 1.34, 0.644 on wheat. Tertiary mixture tests showed EC50 values (TU/kg soil) of (Alachlor + Bromacil + Diuron) was 633.9 on melon, 3.02 on molokhia and 32.174 on wheat. Diuron was more toxic than Alachlor and Bromacil to the tested crops based on individual tests. Molokhia was the most sensitive crop to herbicides. Binary mixtures showed a synergistic effect as compared to the tertiary mixtures.

  1. Purification of phytotoxic metabolites from culture filtrate of Fusarium oxysporum f. sp. cubense gcv 01210 (race 1

    Directory of Open Access Journals (Sweden)

    Nayanci Portal

    2011-04-01

    Full Text Available Panama disease, caused by Fusarium oxysporum f. sp. cubense, is considered a destructive disease of economic importance in the genus Musa. The culture filtrates of the pathogen have been used to differentiate cultivars, but have not been identified metabolites involved in the differential response. The aim of this study was to purify phytotoxic metabolites present in the culture filtrate of Fusarium oxysporum f. sp. cubense GCV [01210] Race 1 for further chemical characterization. We used a culture filtrate of 15 days of incubation. The phytotoxic activity was tested with a leaf bioassay on the susceptible cultivar ‘Gros Michel’ and resistant ‘FHIA 01’. The organic extract was extracted and fractionated. It was partitioned with organic solvents of rising polarity and found the complexity of each of the fractions by TLC. The metabolites were purified by flash column chromatography. Two compounds were purified from the culture filtrate of the pathogen which not only differed in color (blue and pale yellow, but also in polarity. Fractions B (containing blue compound and E (containing yellow compound produced significant differences in lesion area between resistant and susceptible cultivar. These results are not conclusive but, it is the basis for the identification of compounds involved in the differential response of Musa spp. cultivars to the culture filtrate of Fusarium oxysporum f. sp. cubense. Key Words: phytotoxic activity, chromatography, organic extract, Panama disease, plantains and bananas

  2. Phytotoxicity of wastewater-born micropollutants – Characterisation of three antimycotics and a cationic surfactant

    International Nuclear Information System (INIS)

    Richter, Elisabeth; Roller, Elias; Kunkel, Uwe; Ternes, Thomas A.; Coors, Anja

    2016-01-01

    Sewage sludge applied to soil may be a valuable fertiliser but can also introduce poorly degradable and highly adsorptive wastewater-born residues of pharmaceuticals and personal care products (PPCPs) to the soil, posing a potential risk to the receiving environment. Three azole antimycotics (climbazole, ketoconazole and fluconazole), and one quaternary ammonium compound (benzyldimethyldodecylammonium chloride, BDDA) that are frequently detected in municipal sewage sludge and/or treated wastewater were therefore characterised in their toxicity toward terrestrial (Brassica napus) and aquatic (Lemna minor) plants. Fluconazole and climbazole showed the greatest toxicity to B. napus, while toxicity of ketoconazole and BDDA was by one to two orders of magnitude lower. Sludge amendment to soil at an agriculturally realistic rate of 5 t/ha significantly reduced the bioconcentration of BDDA in B. napus shoots compared to tests without sludge amendment, although not significantly reducing phytotoxicity. Ketoconazole, fluconazole and BDDA proved to be very toxic to L. minor with median effective concentrations ranging from 55.7 μg/L to 969 μg/L. In aquatic as well as terrestrial plants, the investigated azoles exhibited growth-retarding symptoms presumably related to an interference with phytohormone synthesis as known for structurally similar fungicides used in agriculture. While all four substances exhibited considerable phytotoxicity, the effective concentrations were at least one order of magnitude higher than concentrations measured in sewage sludge and effluent. Based on preliminary hazard quotients, BDDA and climbazole appeared to be of greater environmental concern than the two pharmaceuticals fluconazole and ketoconazole. - Highlights: • Azole antimycotics and the investigated QAC are highly toxic toward aquatic plants at concentrations in the µg/L range. • Climbazole and fluconazole are very toxic toward terrestrial plants and show symptoms specific

  3. Executive Functions in Developmental Dyslexia

    Directory of Open Access Journals (Sweden)

    Pamela eVarvara

    2014-03-01

    Full Text Available The present study was aimed at investigating different aspects of Executive Functions (EF in children with Developmental Dyslexia (DD.A neuropsychological battery tapping verbal fluency, spoonerism, attention, verbal shifting, short-term and working memory was used to assess 60 children with DD and 65 with typical reading abilities.Compared to their controls, children with DD showed deficits in several EF domains such as verbal categorical and phonological fluency, visual-spatial and auditory attention, spoonerism, verbal and visual short-term memory, and verbal working memory. Moreover, exploring predictive relationships between EF measures and reading, we found that spoonerism abilities better explained word and non-word reading deficits. Although to a lesser extent, auditory and visual-spatial attention also explained the increased percentage of variance related to reading deficit.EF deficits found in DD are interpreted as an expression of a deficient functioning of the Central Executive System and are discussed in the context of the recent temporal sampling theory.

  4. What executives should remember.

    Science.gov (United States)

    Drucker, Peter F

    2006-02-01

    In more than 30 essays for Harvard Business Review, Peter Drucker (1909-2005) urged readers to take on the hard work of thinking--always combined, he insisted, with decisive action. He closely analyzed the phenomenon of knowledge work--the growing call for employees who use their minds rather than their hands--and explained how it challenged the conventional wisdom about the way organizations should be run. He was intrigued by employees who knew more about certain subjects than their bosses or colleagues but who still had to cooperate with others in a large organization. As the business world matured in the second half of the twentieth century, executives came to think that they knew how to run companies--and Drucker took it upon himself to poke holes in their assumptions, lest organizations become stale. But he did so sympathetically, operating from the premise that his readers were intelligent, hardworking people of goodwill. Well suited to HBR's format of practical, idea-based essays for executives, his clear-eyed, humanistic writing enriched the magazine time and again. This article is a compilation of the savviest management advice Drucker offered HBR readers over the years--in short, his greatest hits. It revisits the following insightful, influential contributions: "The Theory of the Business" (September-October 1994), "Managing for Business Effectiveness" (May-June 1963), "What Business Can Learn from Nonprofits" (July-August 1989), "The New Society of Organizations" (September-October 1992), "The Information Executives Truly Need" (January-February 1995), "Managing Oneself" (March-April 1999 republished January 2005), "They're Not Employees, They're People" (February 2002), "What Makes an Effective Executive" (June 2004).

  5. INTERNATIONALIZATION OF CHINESE EXECUTIVES

    OpenAIRE

    Lingfang Fayol-Song

    2012-01-01

    Over the last two decades, Chinese nationals have increasingly been employed by multinational companies (MNCs) operating in China taking positions previously occupied by foreign expatriates from investor countries. The development of local managers has therefore become crucial in the field of human resource management because the success of these companies depends greatly upon the ability and competence of their executive management class. The present paper addresses the issue of how to devel...

  6. Concurrent Models for Object Execution

    OpenAIRE

    Diertens, Bob

    2012-01-01

    In previous work we developed a framework of computational models for the concurrent execution of functions on different levels of abstraction. It shows that the traditional sequential execution of function is just a possible implementation of an abstract computational model that allows for the concurrent execution of functions. We use this framework as base for the development of abstract computational models that allow for the concurrent execution of objects.

  7. Executive Energy Leadership Academy | NREL

    Science.gov (United States)

    Executive Energy Leadership Academy Executive Energy Leadership Academy NREL's Executive Energy Leadership Academy is a nationally renowned program that provides non-technical business, governmental, and foreground. Leadership Program The Leadership Program is designed for community and industry leaders with an

  8. Stereoselective phytotoxicity of HCH mediated by photosynthetic and antioxidant defense systems in Arabidopsis thaliana.

    Science.gov (United States)

    Zhang, Qiong; Zhou, Cong; Zhang, Quan; Qian, Haifeng; Liu, Weiping; Zhao, Meirong

    2013-01-01

    Hexachlorocyclohexane (HCH) has been used for plant protection and sanitation world-widely, and its isomers have been detected in water, soil, and air as well as in vegetation. As a sink for lipophilic pollutants, vegetation is very important for the degradation and fate of organic contamination; however, little was known about their phytotoxicity and mechanisms of toxic effect. In this study, the stereoselective phototoxicity of four isomers (α, β, γ, and δ) of HCHs mediated by independent as well as interconnecting systems of photosynthesis and enzymatic antioxidant defense system in Arabidopsis thaliana were assessed. Our results revealed that all the HCHs not only stimulated the activities of catalase (CAT) and peroxidase (POD), but also inhibited the activity of superoxide dismutase (SOD). In photosynthesis system, the photosynthetic efficiency of PSI and PSII were all down regulated. Meanwhile, results from both systems showed that δ-HCH was the most toxic one, while α-HCH the least in Arabidopsis thaliana. For the first time, stereoselective effects of different isomers of HCH in plant were demonstrated. And the results suggest that it requires further research to fully elucidate the environmental toxicity and their mechanisms.

  9. Stereoselective phytotoxicity of HCH mediated by photosynthetic and antioxidant defense systems in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Qiong Zhang

    Full Text Available BACKGROUND: Hexachlorocyclohexane (HCH has been used for plant protection and sanitation world-widely, and its isomers have been detected in water, soil, and air as well as in vegetation. As a sink for lipophilic pollutants, vegetation is very important for the degradation and fate of organic contamination; however, little was known about their phytotoxicity and mechanisms of toxic effect. In this study, the stereoselective phototoxicity of four isomers (α, β, γ, and δ of HCHs mediated by independent as well as interconnecting systems of photosynthesis and enzymatic antioxidant defense system in Arabidopsis thaliana were assessed. PRINCIPAL FINDINGS: Our results revealed that all the HCHs not only stimulated the activities of catalase (CAT and peroxidase (POD, but also inhibited the activity of superoxide dismutase (SOD. In photosynthesis system, the photosynthetic efficiency of PSI and PSII were all down regulated. Meanwhile, results from both systems showed that δ-HCH was the most toxic one, while α-HCH the least in Arabidopsis thaliana. CONCLUSIONS: For the first time, stereoselective effects of different isomers of HCH in plant were demonstrated. And the results suggest that it requires further research to fully elucidate the environmental toxicity and their mechanisms.

  10. Short-term experiments for determination of the relative phytotoxicity of nitrogen dioxide

    Energy Technology Data Exchange (ETDEWEB)

    van Haut, H.

    1975-01-01

    In short-term experiments, the relative phytotoxicity of nitrogen dioxide was determined for 60 types of plants by comparing it with that of sulfur dioxide. The plants, which included crop and garden plants such as alfalfa, clover, barley, lettuce, carrots, parsley, radishes, onions, beans, and tobacco; ornamental plants, such as roses, dahlias, and gladioli; and coniferous and deciduous trees, such as pines, spruces, birches, and maples, were exposed to the two gases in parallel experiments. The exposure concentrations were 5 to 20 mg NO/sub 2/ cu/m air and 1.5 to 4 mg SO/sub 2//cu m air. Taking the average concentration ratio of SO/sub 2/ to NO/sub 2/ of 1/3.5 and an SO/sub 2/ long-term value of 0.1 mg SO/sub 2//cu m, an average value of 0.35 mg NO/sub 2//cu m of air was obtained for the vegetation half-year. The average value obtained for a 30-min period was 0.80 mg NO/sub 2//cu m of air.

  11. By-product identification and phytotoxicity of biodegraded Direct Yellow 4 dye.

    Science.gov (United States)

    Nouren, Shazia; Bhatti, Haq Nawaz; Iqbal, Munawar; Bibi, Ismat; Kamal, Shagufta; Sadaf, Sana; Sultan, Misbah; Kausar, Abida; Safa, Yusra

    2017-02-01

    Citrus limon peroxidase mediated decolourization of Direct Yellow 4 (DY4) was investigated. The process variables (pH, temperature, incubation time, enzyme dose, H 2 O 2 amount, dye concentration, co-metal ions and surfactants) were optimized for maximum degradation of dye. Maximum dye decolourization of 89.47% was achieved at pH 5.0, temperature 50 °C, enzyme dose 24 U/mL, H 2 O 2 concentration 0.25 mM and DY4 concentration 18.75 mg/L and incubation time 10 min. The co-metal ions and surfactants did not affect the dye decolourization significantly. Response surface analysis revealed that predicted values were in agreement with experimentally determined responses. The degradation products were identified by UPLC/MS analysis and degradation pathway was proposed. Besides, phytotoxicity assay revealed a considerable detoxification in response of biodegradation of DY4 dye. C. limon showed promising efficiency for DY4 degradation and could possibly be used for the remediation of textile effluents. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Copper Oxide Nanoparticle Foliar Uptake, Phytotoxicity, and Consequences for Sustainable Urban Agriculture.

    Science.gov (United States)

    Xiong, TianTian; Dumat, Camille; Dappe, Vincent; Vezin, Hervé; Schreck, Eva; Shahid, Muhammad; Pierart, Antoine; Sobanska, Sophie

    2017-05-02

    Throughout the world, urban agriculture supplies fresh local vegetables to city populations. However, the increasing anthropogenic uses of metal-containing nanoparticles (NPs) such as CuO-NPs in urban areas may contaminate vegetables through foliar uptake. This study focused on the CuO-NP transfer processes in leafy edible vegetables (i.e., lettuce and cabbage) to assess their potential phytotoxicity. Vegetables were exposed via leaves for 5, 10, or 15 days to various concentrations of CuO-NPs (0, 10, or 250 mg per plant). Biomass and gas exchange values were determined in relation to the Cu uptake rate, localization, and Cu speciation within the plant tissues. High foliar Cu uptake occurred after exposure for 15 days for lettuce [3773 mg (kg of dry weight) -1 ] and cabbage [4448 mg (kg of dry weight) -1 ], along with (i) decreased plant weight, net photosynthesis level, and water content and (ii) necrotic Cu-rich areas near deformed stomata containing CuO-NPs observed by scanning electron microscopy and energy dispersive X-ray microanalysis. Analysis of the CuO-NP transfer rate (7.8-242 μg day -1 ), translocation of Cu from leaves to roots and Cu speciation biotransformation in leaf tissues using electron paramagnetic resonance, suggests the involvement of plant Cu regulation processes. Finally, a potential health risk associated with consumption of vegetables contaminated with CuO-NPs was highlighted.

  13. The endogenous nitric oxide mediates selenium-induced phytotoxicity by promoting ROS generation in Brassica rapa.

    Directory of Open Access Journals (Sweden)

    Yi Chen

    Full Text Available Selenium (Se is suggested as an emerging pollutant in agricultural environment because of the increasing anthropogenic release of Se, which in turn results in phytotoxicity. The most common consequence of Se-induced toxicity in plants is oxidative injury, but how Se induces reactive oxygen species (ROS burst remains unclear. In this work, histofluorescent staining was applied to monitor the dynamics of ROS and nitric oxide (NO in the root of Brassica rapa under Se(IV stress. Se(IV-induced faster accumulation of NO than ROS. Both NO and ROS accumulation were positively correlated with Se(IV-induced inhibition of root growth. The NO accumulation was nitrate reductase (NR- and nitric oxide synthase (NOS-dependent while ROS accumulation was NADPH oxidase-dependent. The removal of NO by NR inhibitor, NOS inhibitor, and NO scavenger could alleviate Se(IV-induced expression of Br_Rbohs coding for NADPH oxidase and the following ROS accumulation in roots, which further resulted in the amelioration of Se(IV-induced oxidative injury and growth inhibition. Thus, we proposed that the endogenous NO played a toxic role in B. rapa under Se(IV stress by triggering ROS burst. Such findings can be used to evaluate the toxic effects of Se contamination on crop plants.

  14. Phytotoxicity of carbon nanotubes in soybean as determined by interactions with micronutrients

    Energy Technology Data Exchange (ETDEWEB)

    Zaytseva, Olga, E-mail: olga.zaytseva@uni-hohenheim.de [University of Hohenheim, Institute of Crop Science (340h), Faculty of Agriculture (Germany); Wang, Zhengrui [Academia Sinica, Agricultural Biotechnology Research Center (China); Neumann, Günter [University of Hohenheim, Institute of Crop Science (340h), Faculty of Agriculture (Germany)

    2017-02-15

    Carbon nanomaterials released into the environment exert extremely variable effects on living organisms. In this study, we used soybean (Glycine max) to investigate early responses to seed exposure to multi-walled carbon nanotubes (MWCNTs, outer diameter 20–70 nm, inner diameter 5–10 nm, length of >2 μm). Soybean seeds were imbibed with deionised water (control) or MWCNT suspension (1000 mg L{sup −1}) and were analysed for MWCNT contamination using light microscopy. The seedlings vitality status was evaluated by staining with triphenyltetrazolium chloride and measurement of oxidative stress indicators in the root tissue. Micronutrient (Zn, Mn, Cu) availability in different seedling organs was assessed and the effects of antioxidants, and micronutrient supplementation was investigated. Oxidative stress induction by MWCNTs was detectable in radicle tips, coincided with MWCNTs accumulation and was reverted by external application of proline as antioxidant and micronutrients (Zn, Cu, Mn) as cofactors for various enzymes involved in oxidative stress defence. Accordingly, SOD activity increased after Zn supplementation. During germination, the MWCNT treatments reduced Zn translocation from the cotyledons to the seedling and MWCNTs exhibited adsorption potential for Zn and Cu, which may be involved in internal micronutrients immobilisation. This study demonstrates for the first time that MWCNT phytotoxicity is linked with oxidative stress-related disturbances of micronutrient homeostasis.

  15. Phytotoxicity of carbon nanotubes in soybean as determined by interactions with micronutrients

    International Nuclear Information System (INIS)

    Zaytseva, Olga; Wang, Zhengrui; Neumann, Günter

    2017-01-01

    Carbon nanomaterials released into the environment exert extremely variable effects on living organisms. In this study, we used soybean (Glycine max) to investigate early responses to seed exposure to multi-walled carbon nanotubes (MWCNTs, outer diameter 20–70 nm, inner diameter 5–10 nm, length of >2 μm). Soybean seeds were imbibed with deionised water (control) or MWCNT suspension (1000 mg L"−"1) and were analysed for MWCNT contamination using light microscopy. The seedlings vitality status was evaluated by staining with triphenyltetrazolium chloride and measurement of oxidative stress indicators in the root tissue. Micronutrient (Zn, Mn, Cu) availability in different seedling organs was assessed and the effects of antioxidants, and micronutrient supplementation was investigated. Oxidative stress induction by MWCNTs was detectable in radicle tips, coincided with MWCNTs accumulation and was reverted by external application of proline as antioxidant and micronutrients (Zn, Cu, Mn) as cofactors for various enzymes involved in oxidative stress defence. Accordingly, SOD activity increased after Zn supplementation. During germination, the MWCNT treatments reduced Zn translocation from the cotyledons to the seedling and MWCNTs exhibited adsorption potential for Zn and Cu, which may be involved in internal micronutrients immobilisation. This study demonstrates for the first time that MWCNT phytotoxicity is linked with oxidative stress-related disturbances of micronutrient homeostasis.

  16. Cytotoxicity, Genotoxicity, and Phytotoxicity of Tannery Effluent Discharged into Palar River Basin, Tamil Nadu, India

    Directory of Open Access Journals (Sweden)

    Suki Roy

    2015-01-01

    Full Text Available Ambur, a town located on the banks of Palar River, is considered one of the most polluted areas in India and occupied by hundreds of tanneries and leather product units. The present study was designed to evaluate the toxic effect of discharged tannery effluent (TE on model agricultural crops, ecofriendly microorganisms, and human blood cells. The phytotoxic effects of TE tested on Allium cepa and Lemna minor revealed inhibition of root growth and significant reduction in number of fronds, protein, and chlorophyll content. Moreover, TE induced chlorosis and tissue necrosis in Nostoc muscorum at low concentration (10%. TE has also negative impact on ecofriendly microorganisms, Bacillus thuringiensis, Rhizobium etli, and Aspergillus terreus which play an important role in the nutrition of plant growth. The genotoxicity of TE was investigated in human leukocytes which showed interference with normal mitotic division with subsequent cell lysis. It also intervened with the normal replication process and induced micronucleus formation in the healthy leukocyte. 5% concentration of TE has been revealed to be toxic to erythrocytes. From this study TE found in the Palar River of Ambur has adverse effects on all the three levels of organisms in ecosystem even at lower concentrations.

  17. Cytotoxicity, Genotoxicity, and Phytotoxicity of Tannery Effluent Discharged into Palar River Basin, Tamil Nadu, India

    Science.gov (United States)

    Roy, Suki; Nagarchi, Lubbnaz; Das, Ishita; Mangalam Achuthananthan, Jayasri; Krishnamurthy, Suthindhiran

    2015-01-01

    Ambur, a town located on the banks of Palar River, is considered one of the most polluted areas in India and occupied by hundreds of tanneries and leather product units. The present study was designed to evaluate the toxic effect of discharged tannery effluent (TE) on model agricultural crops, ecofriendly microorganisms, and human blood cells. The phytotoxic effects of TE tested on Allium cepa and Lemna minor revealed inhibition of root growth and significant reduction in number of fronds, protein, and chlorophyll content. Moreover, TE induced chlorosis and tissue necrosis in Nostoc muscorum at low concentration (10%). TE has also negative impact on ecofriendly microorganisms, Bacillus thuringiensis, Rhizobium etli, and Aspergillus terreus which play an important role in the nutrition of plant growth. The genotoxicity of TE was investigated in human leukocytes which showed interference with normal mitotic division with subsequent cell lysis. It also intervened with the normal replication process and induced micronucleus formation in the healthy leukocyte. 5% concentration of TE has been revealed to be toxic to erythrocytes. From this study TE found in the Palar River of Ambur has adverse effects on all the three levels of organisms in ecosystem even at lower concentrations. PMID:26839546

  18. Phytotoxic effects and chemical analysis of leaf extracts from three Phytolaccaceae species in South Korea.

    Science.gov (United States)

    Kim, Yong Ok; Johnson, Jon D; Lee, Eun Ju

    2005-05-01

    We analyzed phenolic compounds and other elements in leaf extracts and compared morphology of three species of the Phytolaccaceae family found in South Korea. To test allelochemical effects of the three Phytolacca species, we also examined seed germination and dry weight of seedlings of Lactuca indica and Sonchus oleraceus treated with leaf extracts. The concentrations of total phenolic compounds were exotic Phytolacca esculenta (3.9 mg/l), native Phytolacca insularis (4.4 mg/l), and exotic Phytolacca americana (10.2 mg/l). There was no significant difference in concentrations between P. esculenta and P. insularis, but the concentration of total phenolics in P. americana was two times higher than either P. esculenta or P. insularis. Analysis of aqueous extracts by HPLC showed seven phenolic compounds (gallic acid, protocatechuic acid, chlorogenic acid, caffeic acid, m-hydroxybenzoic acid, p-coumaric acid, and cinnamic acid). Total phenolics in P. americana were eight to 16 times higher than either P. esculenta or P. insularis, respectively. P. americana inhibited seed germination and dry weight of the two assay species. The phytotoxic effects of the two Phytolacca species were different, despite the fact that P. esculenta and P. insularis had similar levels of total phenolic compounds. We also found that P. americana had invaded Ullung Island, which suggested that P. americana had excellent adaptability to the environment. The three species of Phytolaccaceae in South Korea can be distinguished by their different allelopathic potentials and morphologies.

  19. Allelochemical regulation of reproduction and seed germination of two BrazilianBaccharis species by phytotoxic trichothecenes.

    Science.gov (United States)

    Kuti, J O; Jarvis, B B; Mokhtari-Rejali, N; Bean, G A

    1990-12-01

    The potent phytotoxic trichothecene roridins and baccharinoids occur naturally in the Brazilian plants,Baccharis coridifolia andB. megapotamica. Biosynthesis of roridins inB. coridifolia appears to be linked to pollination, and the phytotoxins then accumulate in the seed. The roles of the phytotoxins in pollination, seed maturation, and germination of theBaccharis species were investigated. The high production of roridins occurred only in seeds resulting from intraspecific pollination, and the concentration of the toxins in the seeds generally increased with seed maturity. Removal of seed coats from trichothecene-producing BrazilianBaccharis species (B. coridifolia andB. megapotamica) and non-trichothecene-producing AmericanBaccharis species (B. halimifolia andB. glutinosa) resulted in improved seed germination ofB. halimifolia andB. glutinosa but complete inhibition of seed germination ofB. coridifolia andB. megapotamica. Addition of seed coat extracts of the BrazilianBaccharis species of dilute solutions (10(-6)μg/ml) of roridins or baccharinoids to the decoated seeds ofB. coridifolia andB. megapotamica resulted in germination, while seeds ofB. halimifolia andB. glutinosa were killed by the phytotoxins. Roridins interacted with gibberellic acid, a germination promoter, but not with abscisic acid, a germination inhibitor. The results from this study suggest that macrocyclic trichothecenes have a regulatory role(s) on reproduction and germination of BrazilianBaccharis species in their natural habitat.

  20. A survey of synthetic and natural phytotoxic compounds and phytoalexins as potential antimalarial compounds.

    Science.gov (United States)

    Bajsa, Joanna; Singh, Kshipra; Nanayakkara, Dhammika; Duke, Stephen Oscar; Rimando, Agnes Mamaril; Evidente, Antonio; Tekwani, Babu Lal

    2007-09-01

    The apicomplexan parasites pathogens such as Plasmodium spp. possess an apicoplast, a plastid organelle similar to those of plants. The apicoplast has some essential plant-like metabolic pathways and processes, making these parasites susceptible to inhibitors of these functions. The main objective of this paper is to determine if phytotoxins with plastid target sites are more likely to be good antiplasmodial compounds than are those with other modes of action. The antiplasmodial activities of some compounds with established phytotoxic action were determined in vitro on a chloroquine (CQ) sensitive (D6, Sierra Leone) strain of Plasmodium falciparum. In this study, we provide in vitro activities of almost 50 such compounds, as well as a few phytoalexins against P. falciparum. Endothall, anisomycin, and cerulenin had sufficient antiplasmodial action to be considered as new lead antimalarial structures. Some derivatives of fusicoccin possessed markedly improved antiplasmodial action than the parent compound. Our results suggest that phytotoxins with plastid targets may not necessarily be better antiplasmodials than those that act at other molecular sites. The herbicides, phytotoxins and the phytoalexins reported here with significant antiplasmodial activity may be useful probes for identification of new antimalarial drug targets and may also be used as new lead structures for new antiplasmodial drug discovery.

  1. Thermal-treated soil for mercury removal: Soil and phytotoxicity tests

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Y.; Edwards, N.T.; Lee, S.Y.; Stiles, C.A.; Armes, S.; Foss, J.E.

    2000-04-01

    Mercury (Hg) contamination of soils and sediments is one of many environmental problems at the Oak Ridge Reservation, Oak Ridge, TN. Mercury-contaminated soil from the Lower East Fork Poplar Creek (LEFPC) at the Oak Ridge Reservation was treated thermally to reduce Hg concentration to a below target level (20 mg kg{sup {minus}1}) as a pilot scale thermal treatment demonstration. As a part of performance evaluation, the soil characteristics and plant growth response of the untreated and treated soil were examined. The soil treated at 350 C retained most of its original soil properties, but the soil treated at 600 C exhibited considerable changes in mineralogical composition and physicochemical characteristics. Growth and physiological response of the three plant species radish (Raphanus sativus L.), fescue (Festuca arundinacea Schreb.), and oat (Avena sativa L.) indicated adverse effects of the thermal treatment. The addition of N fertilizer had beneficial effects in the 350 C treated soil, but had little beneficial effect in the 600 C treated soil. Some changes of soil characteristics induced by thermal treatment cannot be avoided. Soil characteristics and phytotoxicity test results strongly suggest that changes occurring following the 350 C treatment do not limit the use of the treated soil to refill the excavated site for full-scale remediation. The only problem with the 350 C treatment is that small amounts of Hg compounds (<15 mg kg{sup {minus}1}) remain in the soil and a processing cost of $45/Mg.

  2. China's SOE Executives

    DEFF Research Database (Denmark)

    Brødsgaard, Kjeld Erik; Hubbard, Paul; Cai, Guilong

    2017-01-01

    Drawing on a database tracking the career of 1,250 top Chinese executives from 1,084 publicly-listed state-owned enterprises (SOEs), this article analyzes differences in career incentives for subsidiaries controlled by the central government compared to those controlled by local governments. It a...... of promotion. However, in the case of central SOE subsidiaries, leaders are more likely to be promoted based on financial performance. For both central and local 'direct' SOE groups age is a significant negative factor for promotion, whereas tenure is a significant positive factor....

  3. Studies on the concentrations and enrichment of potentially phytotoxic organic pollutants in rain, cloud, and fogwater. Untersuchungen zum Vorkommen und zur Anreicherung potentiell phytotoxischer organischer Umweltgifte in der Nebeldeposition

    Energy Technology Data Exchange (ETDEWEB)

    Herterich, R.; Herrmann, R. (Bayreuth Univ. (Germany, F.R.). Lehrstuhl fuer Hydrologie)

    1989-07-01

    Measurements of organic pollutants in rain, cloud- and fogwater indicate that among other phytotoxic compounds especially nitrated phenols reach deposition rates which can possibly exert harmfull effects on vegetation. We present a highly efficient fogwater collector and a wet deposition sampler for the analysis of organic trace substances. Their arrangement for comparative wet deposition studies in the Alpes and the Fichtelgebirge is shown. Preliminary results show maximum fogwater contaminations up to 2 {mu}molx1{sup -1} for 4-nitrophenol and 4-nitrocresols including both pollutants. At highly exposed mountain sites deposition of these compounds into spruce stands via fogwater can reach several mgxm{sup -2} within a period of 10 days. (orig.).

  4. Structure-dependent phytotoxicity of catechins and other flavonoids: flavonoid conversions by cell-free protein extracts of Centaurea maculosa (spotted knapweed) roots.

    Science.gov (United States)

    Bais, Harsh Pal; Walker, Travis S; Kennan, Alan J; Stermitz, Frank R; Vivanco, Jorge M

    2003-02-12

    Invasive plants are believed to succeed in part by secretion of allelochemicals, thus displacing competing plant species. Centaurea maculosa (spotted knapweed) provides a classic example of this process. We have previously reported that spotted knapweed roots secrete (+/-)-catechin and that (-)-catechin, but not (+)-catechin, is phytotoxic and hence may be a major contributor to C. maculosa's invasive behavior in the rhizosphere. In this communication, we explore both structure/activity relationships for flavonoid phytotoxicity and possible biosynthetic pathways for root production of (+/-)-catechin. Kaempferol and dihydroquercetin were shown to be phytotoxic, while quercetin was not. Kaempferol was converted to dihydroquercetin and (+/-)-catechin when treated with total root protein extracts from C. maculosa, but quercetin was not. This finding suggests an alteration in the standard flavonoid biosynthetic pathway in C. maculosa roots, whereby kaempferol is not a dead-end product but serves as a precursor to dihydroquercetin, which in turn leads to (+/-)-catechin production.

  5. The selection of a model microalgal species as biomaterial for a novel aquatic phytotoxicity assay

    Energy Technology Data Exchange (ETDEWEB)

    Bengtson Nash, S.M. [National Research Centre for Environmental Toxicology, University of Queensland, Brisbane QLD 4108 (Australia)]. E-mail: s.nash@uq.edu.au; Quayle, P.A. [National Research Centre for Environmental Toxicology, University of Queensland, Brisbane QLD 4108 (Australia); Schreiber, U. [Lehrstuhl Botanik I, Julius-von-Sachs-Institut fuer Biowissenschaften, Universitaet Wuerzburg, D-97082 Wuerzburg (Germany); Mueller, J.F. [National Research Centre for Environmental Toxicology, University of Queensland, Brisbane QLD 4108 (Australia)

    2005-05-15

    A phytotoxicity assay based on the ToxY-PAM dual-channel yield analyser has been developed and successfully incorporated into field assessments for the detection of phytotoxicants in water. As a means of further exploring the scope of the assay application and of selecting a model biomaterial to complement the instrument design, nine algal species were exposed to four chemical substances deemed of priority for water quality monitoring purposes (chlorpyrifos, copper, diuron and nonylphenol ethoxylate). Inter-species differences in sensitivity to the four toxicants varied by a factor of 1.9-100. Measurements of photosystem-II quantum yield using these nine single-celled microalgae as biomaterial corroborated previous studies which have shown that the ToxY-PAM dual-channel yield analyser is a highly sensitive method for the detection of PS-II impacting herbicides. Besides Phaeodactylum tricornutum, the previously applied biomaterial, three other species consistently performed well (Nitzschia closterium, Chlorella vulgaris and Dunaliella tertiolecta) and will be used in further test optimisation experiments. In addition to sensitivity, response time was evaluated and revealed a high degree of variation between species and toxicants. While most species displayed relatively weak and slow responses to copper, C. vulgaris demonstrated an IC{sub 10} of 51 {mu}g L{sup -1}, with maximum response measured within 25 minutes and inhibition being accompanied by a large decrease in fluorescence yield. The potential for this C. vulgaris-based bioassay to be used for the detection of copper is discussed. There was no evidence that the standard ToxY-PAM protocol, using these unicellular algae species, could be used for the detection of chlorpyrifos or nonylphenol ethoxylate at environmentally relevant levels.

  6. Phytotoxicity, uptake, and accumulation of silver with different particle sizes and chemical forms

    Energy Technology Data Exchange (ETDEWEB)

    Quah, Bryan [Southern Illinois University Carbondale, Department of Civil and Environmental Engineering (United States); Musante, Craig; White, Jason C. [The Connecticut Agricultural Experiment Station, Department of Analytical Chemistry (United States); Ma, Xingmao, E-mail: xma@civil.tamu.edu [Texas A& M University, Zachry Department of Civil Engineering (United States)

    2015-06-15

    The antimicrobial property of silver nanoparticles (AgNPs) makes it one of the most commonly encountered nanomaterials in commercial products. Consequently, its detection in the environment is highly likely and its potential toxicity has been heavily investigated. While it is now generally agreed that AgNP itself exerts unique toxicity to plants in addition to that of dissolved silver ion, the accumulation and fate of different forms of silver in plant tissues are unknown. This study investigates the phytotoxicity, accumulation, and transport of Ag with different physical and chemical characteristics (e.g., ionic, nanoparticles, and bulk) in two agricultural crop species: Glycine max (soybean) and Triticum aestivum (wheat). The results showed that different forms of Ag demonstrated differential toxicity in these two species, with the Ag{sup +} at the same nominal concentration displaying the strongest effect on plant growth. Exposure to 5 mg/L of elemental Ag in different forms all resulted in significant deposition on the root surface but its morphology and distribution patterns varied considerably. The Ag transport efficiency from roots to shoots differed with both Ag type and plant species. Notably, the upward transport of AgNPs (20–50 nm) was considerably more substantial than that of bulk Ag (1–3 µm). Cell fractionation studies confirmed that all types of Ag were internalized, with the plant cell wall as the predominant place for element accumulation. The findings demonstrate that Ag toxicity and in planta fate vary with particle type and that such considerations are likely necessary to adequately assess food safety concerns upon NP exposure.

  7. The selection of a model microalgal species as biomaterial for a novel aquatic phytotoxicity assay

    International Nuclear Information System (INIS)

    Bengtson Nash, S.M.; Quayle, P.A.; Schreiber, U.; Mueller, J.F.

    2005-01-01

    A phytotoxicity assay based on the ToxY-PAM dual-channel yield analyser has been developed and successfully incorporated into field assessments for the detection of phytotoxicants in water. As a means of further exploring the scope of the assay application and of selecting a model biomaterial to complement the instrument design, nine algal species were exposed to four chemical substances deemed of priority for water quality monitoring purposes (chlorpyrifos, copper, diuron and nonylphenol ethoxylate). Inter-species differences in sensitivity to the four toxicants varied by a factor of 1.9-100. Measurements of photosystem-II quantum yield using these nine single-celled microalgae as biomaterial corroborated previous studies which have shown that the ToxY-PAM dual-channel yield analyser is a highly sensitive method for the detection of PS-II impacting herbicides. Besides Phaeodactylum tricornutum, the previously applied biomaterial, three other species consistently performed well (Nitzschia closterium, Chlorella vulgaris and Dunaliella tertiolecta) and will be used in further test optimisation experiments. In addition to sensitivity, response time was evaluated and revealed a high degree of variation between species and toxicants. While most species displayed relatively weak and slow responses to copper, C. vulgaris demonstrated an IC 10 of 51 μg L -1 , with maximum response measured within 25 minutes and inhibition being accompanied by a large decrease in fluorescence yield. The potential for this C. vulgaris-based bioassay to be used for the detection of copper is discussed. There was no evidence that the standard ToxY-PAM protocol, using these unicellular algae species, could be used for the detection of chlorpyrifos or nonylphenol ethoxylate at environmentally relevant levels

  8. Phytotoxicity and groundwater impacts of leaching from thermal treatment residues in roadways.

    Science.gov (United States)

    Phoungthong, Khamphe; Shao, Li-Ming; He, Pin-Jing; Zhang, Hua

    2018-01-01

    The use of coal fly ash (CFA), municipal solid waste incinerator bottom ash (MSWIBA) and flue gas desulfurization residue (FGDR) in road construction has become very common owing to its economical advantages. However, these residues may contain toxic constituents that pose an environmental risk if they leach out and flow through the soil, surface water and groundwater. Therefore, it is necessary to assess the ecotoxicity and groundwater impact of these residues before decisions can be made regarding their utilization for road construction. In this study, the physico-chemical characteristics, leaching and phytotoxicity of these residues were investigated. Specifically, multivariate analyses were used to evaluate the contributions of the leaching constituents of the CFA, MSWIBA and FGDR leachates to the germination index of wheat seeds. B, Ba, Cr, Cu, Fe and Pb were found to be more toxic to the wheat seeds than the other heavy metals. Furthermore, the leached concentrations of the constituents from the CFA, MSWIBA and FGDR were below the regulatory threshold limits of the Chinese identification standard for hazardous wastes. Analyses conducted using a numerical groundwater model (WiscLEACH) indicated that the predicted field concentrations of metals from the CFA, MSWIBA and FGDR increased with time up to about 30years at the point of compliance, then decreased with time and distance. Overall, this study demonstrated that the risks resulting from MSWIBA, CFA and FGDR leaching could be assessed before its utilization for road construction, providing crucial information for the adoption of these alternative materials. Copyright © 2016. Published by Elsevier B.V.

  9. Application of phytotoxicity data to a new Australian soil quality guideline framework for biosolids

    International Nuclear Information System (INIS)

    Heemsbergen, Diane A.; Warne, Michael St.J.; Broos, Kris; Bell, Mike; Nash, David; McLaughlin, Mike; Whatmuff, Mark; Barry, Glenn; Pritchard, Deb; Penney, Nancy

    2009-01-01

    To protect terrestrial ecosystems and humans from contaminants many countries and jurisdictions have developed soil quality guidelines (SQGs). This study proposes a new framework to derive SQGs and guidelines for amended soils and uses a case study based on phytotoxicity data of copper (Cu) and zinc (Zn) from field studies to illustrate how the framework could be applied. The proposed framework uses normalisation relationships to account for the effects of soil properties on toxicity data followed by a species sensitivity distribution (SSD) method to calculate a soil added contaminant limit (soil ACL) for a standard soil. The normalisation equations are then used to calculate soil ACLs for other soils. A soil amendment availability factor (SAAF) is then calculated as the toxicity and bioavailability of pure contaminants and contaminants in amendments can be different. The SAAF is used to modify soil ACLs to ACLs for amended soils. The framework was then used to calculate soil ACLs for copper (Cu) and zinc (Zn). For soils with pH of 4-8 and OC content of 1-6%, the ACLs range from 8 mg/kg to 970 mg/kg added Cu. The SAAF for Cu was pH dependant and varied from 1.44 at pH 4 to 2.15 at pH 8. For soils with pH of 4-8 and OC content of 1-6%, the ACLs for amended soils range from 11 mg/kg to 2080 mg/kg added Cu. For soils with pH of 4-8 and a CEC from 5-60, the ACLs for Zn ranged from 21 to 1470 mg/kg added Zn. A SAAF of one was used for Zn as it concentrations in plant tissue and soil to water partitioning showed no difference between biosolids and soluble Zn salt treatments, indicating that Zn from biosolids and Zn salts are equally bioavailable to plants

  10. Assessment of Coriolopsis gallica-treated olive mill wastewater phytotoxicity on tomato plants.

    Science.gov (United States)

    Daâssi, Dalel; Sellami, Sahar; Frikha, Fakher; Rodriguez-Couto, Susana; Nasri, Moncef; Mechichi, Tahar

    2016-08-01

    The aim of the present study was to evaluate the phytotoxicity of olive mill wastewater (OMW) after being treated by the white-rot fungus Coriolopsis gallica. For this, the effect of irrigation with treated OMW (TOMW) and untreated OMW (UOMW) on tomato plants (Lycopersicon esculentum) for 3 weeks was studied. The control plants were irrigated with distilled water. Agronomic tests were performed in pot experiments in a greenhouse using the randomized complete block (RCB) experimental design. The relative leaf height (RLH), as a morphological parameter, and the content of total phenols in the roots and total chlorophyll [Cha + Chb] and reducing sugars in the leaves, as physiological parameters, were selected as responses of the experimental design. The results obtained showed that [Cha + Chb] in the leaves of tomato growth under TOMW was enhanced by 36.3 and 19.4 % compared to the plant growth under UOMW and to the controls, respectively. Also, reducing sugar concentrations were closed to those of the control plants, ranging from 0.424 to 0.678 g/L for the different dilutions tested. However, the plants irrigated with UOMW showed lower reducing sugar concentrations ranging from 0.042 to 0.297g/L. The optimum RLH (0.537) was observed in the plants irrigated with TOMW diluted at (1:4), this value being higher than that observed in the controls (0.438). Our study proved that the irrigation with TOMW significantly improved tomato growth and photosynthesis activity over those irrigated with UOMW. Optimization of TOMW as a fertilizer was obtained for a dilution of 1:4. From the obtained results, it can be concluded that OMW treated by C. gallica holds potential to be used as a fertilizer for tomato plants. Graphical Abstract ᅟ Please provide a caption for the graphical abstract.The graphical abstract is improved and sent as attachment Please replace it.

  11. Cadmium phytotoxicity: Quantitative sensitivity relationships between classical endpoints and antioxidative enzyme biomarkers

    Energy Technology Data Exchange (ETDEWEB)

    Rosa Correa, Albertina Xavier da [Centro de Ciencias Tecnologicas da Terra e do Mar, Universidade do Vale do Itajai, Rua Uruguai, 458, 88302-202 Itajai SC (Brazil); Roerig, Leonardo Rubi [Centro de Ciencias Tecnologicas da Terra e do Mar, Universidade do Vale do Itajai, Rua Uruguai, 458, 88302-202 Itajai SC (Brazil); Verdinelli, Miguel A. [Centro de Ciencias Tecnologicas da Terra e do Mar, Universidade do Vale do Itajai, Rua Uruguai, 458, 88302-202 Itajai SC (Brazil); Cotelle, Sylvie [Centre des Sciences de l' Environnement, Universite de Metz, 57000 Metz (France); Ferard, Jean-Francois [Centre des Sciences de l' Environnement, Universite de Metz, 57000 Metz (France); Radetski, Claudemir Marcos [Centro de Ciencias Tecnologicas da Terra e do Mar, Universidade do Vale do Itajai, Rua Uruguai, 458, 88302-202 Itajai SC (Brazil)]. E-mail: radetski@univali.br

    2006-03-15

    In this work, cadmium phytotoxicity and quantitative sensitivity relationships between different hierarchical endpoints in plants cultivated in a contaminated soil were studied. Thus, germination rate, biomass growth and antioxidative enzyme activity (i.e. superoxide dismutase, peroxidase, catalase and glutathione reductase) in three terrestrial plants (Avena sativa L., Brassica campestris L. cv. Chinensis, Lactuca sativa L. cv. hanson) were analyzed. Plant growth tests were carried out according to an International Standard Organization method and the results were analyzed by ANOVA followed by Williams' test. The concentration of Cd{sup 2+} that had the smallest observed significant negative effect (LOEC) on plant biomass was 6.25, 12.5 and 50 mg Cd/kg dry soil for lettuce, oat and Chinese cabbage, respectively. Activity of all enzymes studied increased significantly compared to enzyme activity in plant controls. For lettuce, LOEC values (mg Cd/kg dry soil) for enzymic activity ranged from 0.05 (glutathione reductase) to 0.39 (catalase). For oat, LOEC values (mg Cd/kg dry soil) ranged from 0.19 (for superoxide dismutase and glutathione reductase) to 0.39 (for catalase and peroxidase). For Chinese cabbage, LOEC values (mg Cd/kg dry soil) ranged from 0.19 (peroxidase, catalase and glutathione reductase) to 0.39 (superoxide dismutase). Classical (i.e. germination and biomass) and biochemical (i.e. enzyme activity) endpoints were compared to establish a sensitivity ranking, which was: enzyme activity > biomass > germination rate. For cadmium-soil contamination, the determination of quantitative sensitivity relationships (QSR) between classical and antioxidative enzyme biomarkers showed that the most sensitive plant species have, generally, the lowest QSR values.

  12. Uptake and phytotoxic effect of benzalkonium chlorides in Lepidium sativum and Lactuca sativa.

    Science.gov (United States)

    Khan, Adnan Hossain; Libby, Mark; Winnick, Daniel; Palmer, John; Sumarah, Mark; Ray, Madhumita B; Macfie, Sheila M

    2018-01-15

    Cationic surfactants such as benzalkonium chlorides (BACs) are used extensively as biocides in hospitals, food processing industries, and personal care products. BACs have the potential to reach the rooting zone of crop plants and BACs might thereby enter the food chain. The two most commonly used BACs, benzyl dimethyl dodecyl ammonium chloride (BDDA) and benzyl dimethyl tetradecyl ammonium chloride (BDTA), were tested in a hydroponic system to assess the uptake by and phytotoxicity to lettuce (Lactuca sativa L.) and garden cress (Lepidium sativum L.). Individually and in mixture, BACs at concentrations up to 100 mg L -1 did not affect germination; however, emergent seedlings were sensitive at 1 mg L -1 for lettuce and 5 mg L -1 for garden cress. After 12 d exposure to 0.25 mg L -1 BACs, plant dry weight was reduced by 68% for lettuce and 75% for garden cress, and symptoms of toxicity (necrosis, chlorosis, wilting, etc.) were visible. High performance liquid chromatography-mass spectroscopy analysis showed the presence of BACs in the roots and shoots of both plant species. Although no conclusive relationship was established between the concentrations of six macro- or six micro-nutrients, growth inhibition or BAC uptake, N and Mg concentrations in BAC-treated lettuce were 50% lower than that of control, indicating that BACs might induce nutrient deficiency. Although bioavailability of a compound in hydroponics is significantly higher than that in soil, these results confirm the potential of BACs to harm vascular plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Cadmium phytotoxicity: Quantitative sensitivity relationships between classical endpoints and antioxidative enzyme biomarkers

    International Nuclear Information System (INIS)

    Rosa Correa, Albertina Xavier da; Roerig, Leonardo Rubi; Verdinelli, Miguel A.; Cotelle, Sylvie; Ferard, Jean-Francois; Radetski, Claudemir Marcos

    2006-01-01

    In this work, cadmium phytotoxicity and quantitative sensitivity relationships between different hierarchical endpoints in plants cultivated in a contaminated soil were studied. Thus, germination rate, biomass growth and antioxidative enzyme activity (i.e. superoxide dismutase, peroxidase, catalase and glutathione reductase) in three terrestrial plants (Avena sativa L., Brassica campestris L. cv. Chinensis, Lactuca sativa L. cv. hanson) were analyzed. Plant growth tests were carried out according to an International Standard Organization method and the results were analyzed by ANOVA followed by Williams' test. The concentration of Cd 2+ that had the smallest observed significant negative effect (LOEC) on plant biomass was 6.25, 12.5 and 50 mg Cd/kg dry soil for lettuce, oat and Chinese cabbage, respectively. Activity of all enzymes studied increased significantly compared to enzyme activity in plant controls. For lettuce, LOEC values (mg Cd/kg dry soil) for enzymic activity ranged from 0.05 (glutathione reductase) to 0.39 (catalase). For oat, LOEC values (mg Cd/kg dry soil) ranged from 0.19 (for superoxide dismutase and glutathione reductase) to 0.39 (for catalase and peroxidase). For Chinese cabbage, LOEC values (mg Cd/kg dry soil) ranged from 0.19 (peroxidase, catalase and glutathione reductase) to 0.39 (superoxide dismutase). Classical (i.e. germination and biomass) and biochemical (i.e. enzyme activity) endpoints were compared to establish a sensitivity ranking, which was: enzyme activity > biomass > germination rate. For cadmium-soil contamination, the determination of quantitative sensitivity relationships (QSR) between classical and antioxidative enzyme biomarkers showed that the most sensitive plant species have, generally, the lowest QSR values

  14. Phytotoxic Effects and Phytochemical Fingerprinting of Hydrodistilled Oil, Enriched Fractions, and Isolated Compounds Obtained from Cryptocarya massoy (Oken) Kosterm. Bark.

    Science.gov (United States)

    Rolli, Enrico; Marieschi, Matteo; Maietti, Silvia; Guerrini, Alessandra; Grandini, Alessandro; Sacchetti, Gianni; Bruni, Renato

    2016-01-01

    The hydrodistilled oil of Cryptocarya massoy bark was characterized by GC-FID and GC/MS analyses, allowing the identification of unusual C10 massoia lactone (3, 56.2%), C12 massoia lactone (4, 16.5%), benzyl benzoate (1, 12.7%), C8 massoia lactone (3.4%), δ-decalactone (5, 1.5%), and benzyl salicylate (2, 1.8%) as main constituents. The phytotoxic activities of the oil, three enriched fractions (lactone-rich, ester-rich, and sesquiterpene-rich), and four constituents (compounds 1, 2, 5, and δ-dodecalactone (6)) against Lycopersicon esculentum and Cucumis sativus seeds and seedlings were screened. At a concentration of 1000 μl/l, the essential oil and the massoia lactone-rich fraction caused a complete inhibition of the germination of both seeds, and, when applied on tomato plantlets, they induced an 85 and 100% dieback, respectively. These performances exceeded those of the well-known phytotoxic essential oils of Syzygium aromaticum and Cymbopogon citratus, already used in commercial products for the weed and pest management. The same substances were also evaluated against four phytopathogenic bacteria and ten phytopathogenic fungi, providing EC50 values against the most susceptible strains in the 100-500 μl/l range for the essential oil and in the 10-50 μl/l range for compound 6 and the lactone-rich fraction. The phytotoxic behavior was related mainly to massoia lactones and benzyl esters, while a greater amount of 6 may infer a good activity against some phytopathogenic fungi. Further investigations of these secondary metabolites are warranted, to evaluate their use as natural herbicides. Copyright © 2016 Verlag Helvetica Chimica Acta AG, Zürich.

  15. Build and Execute Environment

    Energy Technology Data Exchange (ETDEWEB)

    2017-04-21

    At exascale, the challenge becomes to develop applications that run at scale and use exascale platforms reliably, efficiently, and flexibly. Workflows become much more complex because they must seamlessly integrate simulation and data analytics. They must include down-sampling, post-processing, feature extraction, and visualization. Power and data transfer limitations require these analysis tasks to be run in-situ or in-transit. We expect successful workflows will comprise multiple linked simulations along with tens of analysis routines. Users will have limited development time at scale and, therefore, must have rich tools to develop, debug, test, and deploy applications. At this scale, successful workflows will compose linked computations from an assortment of reliable, well-defined computation elements, ones that can come and go as required, based on the needs of the workflow over time. We propose a novel framework that utilizes both virtual machines (VMs) and software containers to create a workflow system that establishes a uniform build and execution environment (BEE) beyond the capabilities of current systems. In this environment, applications will run reliably and repeatably across heterogeneous hardware and software. Containers, both commercial (Docker and Rocket) and open-source (LXC and LXD), define a runtime that isolates all software dependencies from the machine operating system. Workflows may contain multiple containers that run different operating systems, different software, and even different versions of the same software. We will run containers in open-source virtual machines (KVM) and emulators (QEMU) so that workflows run on any machine entirely in user-space. On this platform of containers and virtual machines, we will deliver workflow software that provides services, including repeatable execution, provenance, checkpointing, and future proofing. We will capture provenance about how containers were launched and how they interact to annotate

  16. Guidelines for Automation Project Execution

    OpenAIRE

    Takkinen, Heidi

    2011-01-01

    The purpose of this Master’s thesis was to create instructions for executing an automation project. Sarlin Oy Ab needed directions on how to execute an automation project. Sarlin is starting up a new business area offering total project solutions for customers. Sarlin focuses on small and minor automation projects on domestic markets. The thesis represents issues related to project execution starting from the theory of the project to its kick-off and termination. Site work is one importan...

  17. Editor, Executive and Entrepreneur

    DEFF Research Database (Denmark)

    Bøe-Lillegraven, Tor; Wilberg, Erik

    2016-01-01

    To survive in today’s increasingly complex business environments, firms must embrace strategic paradoxes: contradictory yet interrelated objectives that persist over time. This can be one of toughest of all leadership challenges, as managers must accept inconsistency and contradictions....... In this article, we develop and empirically test a set of hypotheses related to ambidexterity, a key example of a paradoxical strategy. Through our analysis of data from a survey of executive leaders, we find a link between organizational ambidexterity and strategic planning, suggesting that the complexities...... of navigating in explorative ventures require more explicit strategy work than the old certainties of a legacy business. We identify and discuss inherent paradoxes and their implications for firm performance in 22 industry-specific strategies, where empirical industry data shows a pattern of conflict between...

  18. Executable Use Cases

    DEFF Research Database (Denmark)

    Jørgensen, Jens Bæk; Bossen, Claus

    2004-01-01

    and into the work processes they're to support. However, prototypes typically provide an explicit representation only of the system itself. Executable use cases, on the other hand, can also describe the environment. EUCs are designed to: narrow the gap between informal ideas about requirements and the formalization...... modeling. This article describes a case study in which developers used EUCs to prototype an electronic patient record system for hospitals in Aarhus, Denmark.......Many software experts argue that when we design a new system, we should create an explicit description of the environment in which the proposed system is to be used. The argument becomes crucial for pervasive computing, which aims to tightly integrate systems into their environments...

  19. Executive Orders-Barack Obama

    Data.gov (United States)

    National Archives and Records Administration — Executive orders are official documents, numbered consecutively, through which the President of the United States manages the operations of the Federal Government....

  20. Two executives, one career.

    Science.gov (United States)

    Cunningham, Cynthia R; Murray, Shelley S

    2005-02-01

    For six years, Cynthia Cunningham and Shelley Murray shared an executive job at Fleet Bank. One desk, one chair, one computer, one telephone, and one voice-mail account. To their clients and colleagues, they were effectively one person, though one person with the strengths and ideas of two, seamlessly handing projects back and forth. Although their department was dissolved after the bank merged with Bank of America, the two continue to consider themselves a package-they have one resume, and they are seeking their next opportunity together. Their choice to share a job was not only a quality-of-life decision but one intended to keep their careers on course: "Taking two separate part-time jobs would have thrown us completely off track" they write in this first-person account."We're both ambitious people, and neither of us wanted just a job. We wanted careers" In this article, the two highly motivated women reveal their determination to manage the demands of both family and career. Flextime,telecommuting, and compressed workweeks are just some of the options open to executives seeking greater work/ life balance, and the job share, as described by Cunningham and Murray, could well be the next solution for those wishing to avoid major trade-offs between their personal and professional lives. Cunningham and Murray describe in vivid detail how they structured their unusual arrangement, how they sold themselves to management, and the hurdles they faced along the way. Theirs is a win-win story, for the company and for them.

  1. Online Synthesis for Operation Execution Time Variability on Digital Microfluidic Biochips

    DEFF Research Database (Denmark)

    Alistar, Mirela; Pop, Paul

    2014-01-01

    have assumed that each biochemical operation in an application is characterized by a worst-case execution time (wcet). However, during the execution of the application, due to variability and randomness in biochemical reactions, operations may finish earlier than their wcets. In this paper we propose...... an online synthesis strategy that re-synthesizes the application at runtime when operations experience variability in their execution time, obtaining thus shorter application execution times. The proposed strategy has been evaluated using several benchmarks....

  2. Disciplining and Screening Top Executives

    NARCIS (Netherlands)

    S. Dominguez Martinez (Silvia); O.H. Swank (Otto); B. Visser (Bauke)

    2006-01-01

    textabstractBoards of directors face the twin task of disciplining and screening executives. To perform these tasks directors do not have detailed information about executives' behaviour, and only infrequently have information about the success or failure of initiated strategies, reorganizations,

  3. Developmental Changes in Executive Functioning

    Science.gov (United States)

    Lee, Kerry; Bull, Rebecca; Ho, Ringo M. H.

    2013-01-01

    Although early studies of executive functioning in children supported Miyake et al.'s (2000) three-factor model, more recent findings supported a variety of undifferentiated or two-factor structures. Using a cohort-sequential design, this study examined whether there were age-related differences in the structure of executive functioning among…

  4. Chemical composition, antimicrobial, insecticidal, phytotoxic and antioxidant activities of Mediterranean Pinus brutia and Pinus pinea resin essential oils.

    Science.gov (United States)

    Ulukanli, Zeynep; Karabörklü, Salih; Bozok, Fuat; Ates, Burhan; Erdogan, Selim; Cenet, Menderes; Karaaslan, Merve Göksin

    2014-12-01

    Essential oils of the resins of Pinus brutia and Pinus pinea were evaluated for their biological potential. Essential oils were characterized using GC-MS and GC/FID. in vitro antimicrobial, phytotoxic, antioxidant, and insecticidal activities were carried out using the direct contact and the fumigant assays, respectively. The chemical profile of the essential oils of the resins of P. pinea and P. brutia included mainly α-pinene (21.39% and 25.40%), β-pinene (9.68% and 9.69%), and caryophyllene (9.12% and 4.81%). The essential oils of P. pinea and P. brutia exerted notable antimicrobial activities on Micrococcus luteus and Bacillus subtilis, insecticidal activities on Ephestia kuehniella eggs, phytotoxic activities on Lactuca sativa, Lepidium sativum, and Portulaca oleracea, as well as antioxidant potential. Indications of the biological activities of the essential oils suggest their use in the formulation of ecofriendly and biocompatible pharmaceuticals. Copyright © 2014 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  5. Short and long-term efficacy and phytotoxicity of phosphine against Rhynchophorus ferrugineus in live Phoenix canariensis palms

    Energy Technology Data Exchange (ETDEWEB)

    Dembilio, O.; Jaques, J.A.

    2015-07-01

    The red palm weevil, Rhynchophorus ferrugineus, is a palm borer native to South Asia which has spread mainly due to the unintended movement of infested planting material. As a result, this species has become the most destructive palm pest in the world. The difficulty of detecting the early stages of infestation due to its cryptic life cycle has led many countries to implement, strict pre- and post-entry quarantine regulations to prevent further spread. However, there are no quarantine protocols to ensure that palm material for planting is free of R. ferrugineus. The aim of this study has been to determine the efficacy of aluminium phosphide as a safe quarantine treatment against different stages of R. ferrugineus and the possible phytotoxic effects on live Phoenix canariensis palms. Our results confirm that a dose of 1.14 g/m3 for 2 days is enough to kill all stages of R. ferrugineus in live palms with no phytotoxic effects on treated palms for up to one year after the treatment. This procedure, which could be easily applied in sealed containers used for palm trade, could drastically reduce risks associated to palm movement worldwide. (Author)

  6. Short communication: Short and long-term efficacy and phytotoxicity of phosphine against Rhynchophorus ferrugineus in live Phoenix canariensis palms

    Directory of Open Access Journals (Sweden)

    Óscar Dembilio

    2015-12-01

    Full Text Available The red palm weevil, Rhynchophorus ferrugineus, is a palm borer native to South Asia which has spread mainly due to the unintended movement of infested planting material. As a result, this species has become the most destructive palm pest in the world. The difficulty of detecting the early stages of infestation due to its cryptic life cycle has led many countries to implement, strict pre- and post-entry quarantine regulations to prevent further spread. However, there are no quarantine protocols to ensure that palm material for planting is free of R. ferrugineus. The aim of this study has been to determine the efficacy of aluminium phosphide as a safe quarantine treatment against different stages of R. ferrugineus and the possible phytotoxic effects on live Phoenix canariensis palms. Our results confirm that a dose of 1.14 g/m3 for 2 days is enough to kill all stages of R. ferrugineus in live palms with no phytotoxic effects on treated palms for up to one year after the treatment. This procedure, which could be easily applied in sealed containers used for palm trade, could drastically reduce risks associated to palm movement worldwide.

  7. Fate and Phytotoxicity of CeO2 Nanoparticles on Lettuce Cultured in the Potting Soil Environment.

    Science.gov (United States)

    Gui, Xin; Zhang, Zhiyong; Liu, Shutong; Ma, Yuhui; Zhang, Peng; He, Xiao; Li, Yuanyuan; Zhang, Jing; Li, Huafen; Rui, Yukui; Liu, Liming; Cao, Weidong

    2015-01-01

    Cerium oxide nanoparticles (CeO2 NPs) have been shown to have significant interactions in plants. Previous study reported the specific-species phytotoxicity of CeO2 NPs by lettuce (Lactuca sativa), but their physiological impacts and vivo biotransformation are not yet well understood, especially in relative realistic environment. Butterhead lettuce were germinated and grown in potting soil for 30 days cultivation with treatments of 0, 50, 100, 1000 mg CeO2 NPs per kg soil. Results showed that lettuce in 100 mg·kg-1 treated groups grew significantly faster than others, but significantly increased nitrate content. The lower concentrations treatment had no impact on plant growth, compared with the control. However, the higher concentration treatment significantly deterred plant growth and biomass production. The stress response of lettuce plants, such as Superoxide dismutase (SOD), Peroxidase (POD), Malondialdehyde(MDA) activity was disrupted by 1000 mg·kg-1 CeO2 NPs treatment. In addition, the presence of Ce (III) in the roots of butterhead lettuce explained the reason of CeO2 NPs phytotoxicity. These findings demonstrate CeO2 NPs modification of nutritional quality, antioxidant defense system, the possible transfer into the food chain and biotransformation in vivo.

  8. Phytotoxicity of the organic phase and major compound obtained from the fruit pulp of Crescentia cujete L. (Bignoniaceae

    Directory of Open Access Journals (Sweden)

    Sinval Garcia Pereira

    2015-09-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2015v28n4p51 The phytotoxity of ethanol extracts, of the organic phase and major compound (cinnamic acid obtained from the fruit pulp of Crescentia cujete L., were evaluated for their potential to inhibit seed germination, hypocotyl development and radicle development of the invasive weeds Senna obtusifolia (L. Irwin & Barneby and Mimosa pudica Mill. The organic phase at a concentration of 0.5% inhibited 100% seed germination of both weeds. Cinnamic acid obtained from the organic phase inhibited seed germination by 95% for S. obtusifolia and 99% for M. pudica at a concentration of 0.1%, with concentrations (% inhibiting 50% (IC50 seed germination equal to 0.063% and 0.037%, respectively. For the seedling growth bioassays, the toxicity of the cinnamic acid was more efficient for the S. obtusifolia radicle (IC50 equal to 0.009%, and for M. pudica the IC50 values were 0.097% and 0.117% for the radicle and hypocotyl, respectively. This research reinforces the phytotoxic potential of cinnamic acid, verified initially in the organic phase (in ethyl acetate, which is rich in this phenylpropanoid. he rainiest months in the Amazon region. The increased BAP and GA3 concentrations in the culture medium provided significant improvements in the material multiplication rates. In spite of the results obtained, the species shows peculiarities and limitations to in vitro cultivation that were identified and described in this paper.

  9. Phytotoxicity of the organic phase and major compound obtained from the fruit pulp of Crescentia cujete L. (Bignoniaceae

    Directory of Open Access Journals (Sweden)

    Sinval Garcia Pereira

    2015-12-01

    Full Text Available The phytotoxity of ethanol extracts, of the organic phase and major compound (cinnamic acid obtained from the fruit pulp of Crescentia cujete L., were evaluated for their potential to inhibit seed germination, hypocotyl development and radicle development of the invasive weeds Senna obtusifolia (L. Irwin & Barneby and Mimosa pudica Mill. The organic phase at a concentration of 0.5% inhibited 100% seed germination of both weeds. Cinnamic acid obtained from the organic phase inhibited seed germination by 95% for S. obtusifolia and 99% for M. pudica at a concentration of 0.1%, with concentrations (% inhibiting 50% (IC50 seed germination equal to 0.063% and 0.037%, respectively. For the seedling growth bioassays, the toxicity of the cinnamic acid was more efficient for the S. obtusifolia radicle (IC50 equal to 0.009%, and for M. pudica the IC50 values were 0.097% and 0.117% for the radicle and hypocotyl, respectively. This research reinforces the phytotoxic potential of cinnamic acid, verified initially in the organic phase (in ethyl acetate, which is rich in this phenylpropanoid.

  10. Fate and Phytotoxicity of CeO2 Nanoparticles on Lettuce Cultured in the Potting Soil Environment.

    Directory of Open Access Journals (Sweden)

    Xin Gui

    Full Text Available Cerium oxide nanoparticles (CeO2 NPs have been shown to have significant interactions in plants. Previous study reported the specific-species phytotoxicity of CeO2 NPs by lettuce (Lactuca sativa, but their physiological impacts and vivo biotransformation are not yet well understood, especially in relative realistic environment. Butterhead lettuce were germinated and grown in potting soil for 30 days cultivation with treatments of 0, 50, 100, 1000 mg CeO2 NPs per kg soil. Results showed that lettuce in 100 mg·kg-1 treated groups grew significantly faster than others, but significantly increased nitrate content. The lower concentrations treatment had no impact on plant growth, compared with the control. However, the higher concentration treatment significantly deterred plant growth and biomass production. The stress response of lettuce plants, such as Superoxide dismutase (SOD, Peroxidase (POD, Malondialdehyde(MDA activity was disrupted by 1000 mg·kg-1 CeO2 NPs treatment. In addition, the presence of Ce (III in the roots of butterhead lettuce explained the reason of CeO2 NPs phytotoxicity. These findings demonstrate CeO2 NPs modification of nutritional quality, antioxidant defense system, the possible transfer into the food chain and biotransformation in vivo.

  11. Unraveling Executive Functioning in Dual Diagnosis.

    Science.gov (United States)

    Duijkers, Judith C L M; Vissers, Constance Th W M; Egger, Jos I M

    2016-01-01

    In mental health, the term dual-diagnosis is used for the co-occurrence of Substance Use Disorder (SUD) with another mental disorder. These co-occurring disorders can have a shared cause, and can cause/intensify each other's expression. Forming a threat to health and society, dual-diagnosis is associated with relapses in addiction-related behavior and a destructive lifestyle. This is due to a persistent failure to control impulses and the maintaining of inadequate self-regulatory behavior in daily life. Thus, several aspects of executive functioning like inhibitory, shifting and updating processes seem impaired in dual-diagnosis. Executive (dys-)function is currently even seen as a shared underlying key component of most mental disorders. However, the number of studies on diverse aspects of executive functioning in dual-diagnosis is limited. In the present review, a systematic overview of various aspects of executive functioning in dual-diagnosis is presented, striving for a prototypical profile of patients with dual-diagnosis. Looking at empirical results, inhibitory and shifting processes appear to be impaired for SUD combined with schizophrenia, bipolar disorder or cluster B personality disorders. Studies involving updating process tasks for dual-diagnosis were limited. More research that zooms in to the full diversity of these executive functions is needed in order to strengthen these findings. Detailed insight in the profile of strengths and weaknesses that underlies one's behavior and is related to diagnostic classifications, can lead to tailor-made assessment and indications for treatment, pointing out which aspects need attention and/or training in one's self-regulative abilities.

  12. Eugenol oil nanoemulsion: antifungal activity against Fusarium oxysporum f. sp. vasinfectum and phytotoxicity on cottonseeds

    Science.gov (United States)

    Abd-Elsalam, Kamel A.; Khokhlov, Alexei R.

    2015-02-01

    The current research deals with the formulation and characterization of bio-based oil-in-water nanoemulsion. The formulated eugenol oil nanoemulsion was characterized by dynamic light scattering, stability test, transmission electron microscopy and thin layer chromatography. The nanoemulsion droplets were found to have a Z-average diameter of 80 nm and TEM study reveals the spherical shape of eugenol oil nanoemulsion (EON). The size of the nanoemulsion was found to be physically stable up to more than 1-month when it was kept at room temperature (25 °C). The TEM micrograph showed that the EON was spherical in shape and moderately mono or di-dispersed and was in the range of 50-110 nm. Three concentrations of the nanoformulation were used to evalute the anti-fusarium activity both in vitro and in vivo experiments. SDS-PAGE results of total protein from the Fusarium oxysporum f. sp. vasinfectum (FOV) isolate before and after treatment with eugenol oil nanoemulsion indicate that the content of extra cellular soluble small molecular proteins decreased significantly in EON-treated fungus. Light micrographs of mycelia and spores treated with EON showed the disruption of the fungal structures. The analysis of variance (ANOVA) for Fusarium wilt incidence indicated highly significant ( p = 0.000) effects of concentration, genotype, and their interaction. The difference in wilt incidence between concentrations and control was not the same for each genotype, that is, the genotypes responded differently to concentrations. Effects of three EON concentration on germination percentage, and radicle length, were determined in the laboratory. One very interesting finding in the current study is that cotton genotypes was the most important factors in determining wilt incidence as it accounted for 93.18 % of the explained (model) variation. In vitro experiments were conducted to evaluate the potential phytotoxic effect of three EON concentrations. Concentration, genotype and

  13. Using Mung Beans as a Simple, Informative Means to Evaluate the Phytotoxicity of Engineered Nanomaterials and Introduce the Concept of Nanophytotoxicity to Undergraduate Students

    Science.gov (United States)

    Ross, Shailise S.; Owen, Matthew J.; Pedersen, Brian P.; Liu, Gang-yu; Miller, William J. W.

    2016-01-01

    This work presents a lecture and lab series that focuses on teaching the concept of nanophytotoxicity to undergraduate students in a relatively simple experiment. In this experiment, students evaluated the phytotoxicity of engineered nanomaterials (ENMs) using mung beans (i.e., "Vigna radiata") and industrially relevant, commercially…

  14. Kinetic study of phytotoxicity induced by foliar lead uptake for vegetables exposed to fine particles and implications for sustainable urban agriculture.

    Science.gov (United States)

    Xiong, TianTian; Austruy, Annabelle; Pierart, Antoine; Shahid, Muhammad; Schreck, Eva; Mombo, Stéphane; Dumat, Camille

    2016-08-01

    At the global scale, foliar metal transfer occurs for consumed vegetables cultivated in numerous urban or industrial areas with a polluted atmosphere. However, the kinetics of metal uptake, translocation and involved phytotoxicity was never jointly studied with vegetables exposed to micronic and sub-micronic particles (PM). Different leafy vegetables (lettuces and cabbages) cultivated in RHIZOtest® devices were, therefore, exposed in a greenhouse for 5, 10 and 15days to various PbO PM doses. The kinetics of transfer and phytotoxicity was assessed in relation to lead concentration and exposure duration. A significant Pb accumulation in leaves (up to 7392mg/kg dry weight (DW) in lettuce) with translocation to roots was observed. Lead foliar exposure resulted in significant phytotoxicity, lipid composition change, a decrease of plant shoot growth (up to 68.2% in lettuce) and net photosynthesis (up to 58% in lettuce). The phytotoxicity results indicated plant adaptation to Pb and a higher sensitivity of lettuce in comparison with cabbage. Air quality needs, therefore, to be considered for the health and quality of vegetables grown in polluted areas, such as certain megacities (in China, Pakistan, Europe, etc.) and furthermore, to assess the health risks associated with their consumption. Copyright © 2016. Published by Elsevier B.V.

  15. Executive Orders from 1994-2013

    Data.gov (United States)

    National Archives and Records Administration — The President of the United States manages the operations of the Executive branch of Government through Executive orders. After the President signs an Executive...

  16. Television and children's executive function.

    Science.gov (United States)

    Lillard, Angeline S; Li, Hui; Boguszewski, Katie

    2015-01-01

    Children spend a lot of time watching television on its many platforms: directly, online, and via videos and DVDs. Many researchers are concerned that some types of television content appear to negatively influence children's executive function. Because (1) executive function predicts key developmental outcomes, (2) executive function appears to be influenced by some television content, and (3) American children watch large quantities of television (including the content of concern), the issues discussed here comprise a crucial public health issue. Further research is needed to reveal exactly what television content is implicated, what underlies television's effect on executive function, how long the effect lasts, and who is affected. © 2015 Elsevier Inc. All rights reserved.

  17. Executive Schedule C System (ESCS)

    Data.gov (United States)

    Office of Personnel Management — Used to store information on Federal employees in the Senior Executive Service (SES) and appointed employees in the Schedule C System. Every four years, just after...

  18. Executive functioning in older adults with hoarding disorder.

    Science.gov (United States)

    Ayers, Catherine R; Wetherell, Julie Loebach; Schiehser, Dawn; Almklov, Erin; Golshan, Shahrokh; Saxena, Sanjaya

    2013-11-01

    Hoarding disorder (HD) is a chronic and debilitating psychiatric condition. Midlife HD patients have been found to have neurocognitive impairment, particularly in areas of executive functioning, but the extent to which this is due to comorbid psychiatric disorders has not been clear. The purpose of the present investigation was to examine executive functioning in geriatric HD patients without any comorbid Axis I disorders (n = 42) compared with a healthy older adult comparison group (n = 25). We hypothesized that older adults with HD would perform significantly worse on measures of executive functioning (Wisconsin Card Sort Task [Psychological Assessment Resources, Lutz, Florida, USA] ( Psychological Assessment Resources, 2003) and the Wechsler Adult Intelligence Scale-IV digit span and letter-number sequencing tests [Pearson, San Antonio, TX, USA]). Older adults with HD showed significant differences from healthy older controls in multiple aspects of executive functioning. Compared with healthy controls, older adults with HD committed significantly more total, non-perseverative errors and conceptual level responses on the Wisconsin Card Sort Task and had significantly worse performance on the Wechsler Adult Intelligence Scale-IV digit span and letter-number sequencing tests. Hoarding symptom severity was strongly correlated with executive dysfunction in the HD group. Compared with demographically-matched controls, older adults with HD have dysfunction in several domains of executive functioning including mental control, working memory, inhibition, and set shifting. Executive dysfunction is strongly correlated with hoarding severity and is not because of comorbid psychiatric disorders in HD patients. These results have broad clinical implications suggesting that executive functioning should be assessed and taken into consideration when developing intervention strategies for older adults with HD. Copyright © 2013 John Wiley & Sons, Ltd.

  19. Innovative behavior in nurse executives.

    Science.gov (United States)

    Adams, C E

    1994-05-01

    This study addresses the problem-solving styles of hospital nurse executives and explores the relationship between problem-solving style and leader effectiveness. The Kirton Adaption-Innovation Inventory (KAI) and the Leader Effectiveness and Adaptability Description-Self (LEAD-S) were the instruments used to survey nurse executives from 66 medium-sized urban California hospitals. The majority of respondents used innovative approaches, but no correlation was found between problem-solving style and leader effectiveness.

  20. Executive functions in anorexia nervosa

    OpenAIRE

    Jauregui-Lobera, Ignacio

    2014-01-01

    Introduction: The pathophysiologic mechanisms that account for the development and persistence of anorexia nervosa (AN) remain unclear. With respect to the neuropsychological functioning, the executive functions have been reported to be altered, especially cognitive flexibility and decision-making processes. Objectives: The aim of this study was to review the current state of the neuropsychological studies focused on anorexia nervosa, especially those highlighting the executive functions. Met...

  1. Supervision of execution of dismantling

    International Nuclear Information System (INIS)

    Canizares, J.

    2015-01-01

    Enresa create and organizational structure that covers various areas involved in effective control of Decommissioning Project. One area is the Technical Supervision of Works Decommissioning Project, as Execution Department dependent Technical Management. In the structure, Execution Department acts as liaison between the project, disciplines involved in developing and specialized companies contracted work to achieve your intended target. Equally important is to ensure that such activities are carried out correctly, according to the project documentation. (Author)

  2. BPELPower—A BPEL execution engine for geospatial web services

    Science.gov (United States)

    Yu, Genong (Eugene); Zhao, Peisheng; Di, Liping; Chen, Aijun; Deng, Meixia; Bai, Yuqi

    2012-10-01

    The Business Process Execution Language (BPEL) has become a popular choice for orchestrating and executing workflows in the Web environment. As one special kind of scientific workflow, geospatial Web processing workflows are data-intensive, deal with complex structures in data and geographic features, and execute automatically with limited human intervention. To enable the proper execution and coordination of geospatial workflows, a specially enhanced BPEL execution engine is required. BPELPower was designed, developed, and implemented as a generic BPEL execution engine with enhancements for executing geospatial workflows. The enhancements are especially in its capabilities in handling Geography Markup Language (GML) and standard geospatial Web services, such as the Web Processing Service (WPS) and the Web Feature Service (WFS). BPELPower has been used in several demonstrations over the decade. Two scenarios were discussed in detail to demonstrate the capabilities of BPELPower. That study showed a standard-compliant, Web-based approach for properly supporting geospatial processing, with the only enhancement at the implementation level. Pattern-based evaluation and performance improvement of the engine are discussed: BPELPower directly supports 22 workflow control patterns and 17 workflow data patterns. In the future, the engine will be enhanced with high performance parallel processing and broad Web paradigms.

  3. A competence executive coaching model

    Directory of Open Access Journals (Sweden)

    Pieter Koortzen

    2010-07-01

    Research purpose: The purpose of this article is to address the training and development needs of these consulting psychologists by presenting a competence executive coaching model for the planning, implementation and evaluation of executive coaching interventions. Research design, approach and method: The study was conducted while one of the authors was involved in teaching doctoral students in consulting psychology and executive coaching, specifically in the USA. The approach involved a literature review of executive coaching models and a qualitative study using focus groups to develop and evaluate the competence executive coaching model. Main findings: The literature review provided scant evidence of competence executive coaching models and there seems to be a specific need for this in the training of coaches in South Africa. Hence the model that was developed is an attempt to provide trainers with a structured model for the training of coaches. Contribution/value-add: The uniqueness of this competence model is not only described in terms of the six distinct coaching intervention phases, but also the competencies required in each.

  4. Arsenic- and mercury-induced phytotoxicity in the Mediterranean shrubs Pistacia lentiscus and Tamarix gallica grown in hydroponic culture.

    Science.gov (United States)

    Moreno-Jiménez, E; Esteban, E; Carpena-Ruiz, R O; Peñalosa, J M

    2009-09-01

    Hg and As resistance and bioaccumulation were studied in hydroponically grown Pistacia lentiscus and Tamarix gallica plants. Both elements caused growth inhibition in roots and shoots, with mercury showing greater phytotoxicity than arsenic. Accumulation of both elements by plants increased in response to element supply, with the greatest uptake found in T. gallica. Both elements affected P and Mn status in plants, reduced chlorophyll a concentration and increased MDA and thiol levels. These stress indices showed good correlations with As and Hg concentration in plant tissues, especially in the roots. Toxic responses to mercury were more evident than for arsenic, especially in shoot tissues. T. gallica showed higher resistance to both Hg and As than P. lentiscus, as well accumulating more As and Hg.

  5. Potential phytotoxic and shading effects of invasive Fallopia (Polygonaceae taxa on the germination of native dominant species

    Directory of Open Access Journals (Sweden)

    Lenka Moravcová

    2011-08-01

    Full Text Available Two species of knotweeds (genus Fallopia, Polygonaceae, native to Asia (Fallopia sachalinensis, F. japonica and their hybrid (F. ×bohemica belong to the most noxious plant invaders in Europe and exert a high impact on invaded plant communities that are therefore typically extremely poor in species. The remarkable paucity of invaded communities points to the possible existence of mechanisms suppressing germinating populations of native species in invaded stands. In this pilot study we assessed, under laboratory conditions, whether there are phytotoxic effects of the three Fallopia congeners on seed germination of three target species: two native species commonly growing in habitats that are often invaded by knotweeds (Urtica dioica, Calamagrostis epigejos, and Lepidium sativum, a species commonly used in allelopathic bioassay as a control. Since knotweeds generally form stands with a high cover, we included varying light conditions as an additional factor, to simulate the effects on germination of shading by leaf canopy. The effects of aqueous extracts (2.5, 5.0%, and 0% as a control from dry leaves and rhizomes of the Fallopia congeners on germination of the target species were thus studied under two light regimes, simulating full daylight (white light and light filtered through canopy (green light, and in dark as a control regime. Rhizome extracts did not affect germination. Light treatments yielded inconclusive results, indicating that poor germination and establishment of species in invaded stands is unlikely to be caused by shading alone, but we found a pronounced phytotoxic effect of leaf extracts of Fallopia taxa, more so at 5.0% than 2.5% extract concentration. Fallopia sachalinensis exerted the largest negative effect on the germination of Urtica dioica, F. ×bohemica on that of C.epigejos, and F. japonica had invariably the lowest inhibitory effect. In the field in Central Europe, F. sachalinensis often invades less disturbed, moist

  6. Essential oil composition, phytotoxic and antifungal activities of Ruta chalepensis L. leaves from High Atlas Mountains (Morocco).

    Science.gov (United States)

    Bouajaj, Sana; Romane, Abderrahmane; Benyamna, Abdennaji; Amri, Ismail; Hanana, Mohsen; Hamrouni, Lamia; Romdhane, Mehrez

    2014-01-01

    This study aimed at the determination of chemical composition of essential oil obtained by hydrodistillation, and to evaluate their phytotoxic and antifungal activities. Leaves of Ruta chalepensis L. were collected from the region of Tensift Al Haouz (High Atlas Mountains) Marrakech, Morocco. The essential oil (oil yield is 0.56%) was analysed by GC-FID and GC/MS. Twenty-two compounds were identified and accounted for 92.4% of the total oil composition. The major components were undecan-2-one (49.08%), nonan-2-one (33.15%), limonene (4.19%) and decanone (2.71%). Antifungal ability of essential oils was tested by disc agar diffusion against five plant pathogenic fungi: Fusarium proliferatum, Fusarium pseudograminearum, Fusarium culmorum, Fusarium graminearum and Fusarium polyphialidicum. The oils were also tested in vitro for herbicidal activity by determining their influence on the germination and the shoot and root growth of two weed species, Triticum durum and Phalaris canariensis L.

  7. Biochar amendment to lead-contaminated soil: Effects on fluorescein diacetate hydrolytic activity and phytotoxicity to rice.

    Science.gov (United States)

    Tan, Xiaofei; Liu, Yunguo; Gu, Yanling; Zeng, Guangming; Hu, Xinjiang; Wang, Xin; Hu, Xi; Guo, Yiming; Zeng, Xiaoxia; Sun, Zhichao

    2015-09-01

    The amendment effects of biochar on total microbial activity was measured by fluorescein diacetate (FDA) hydrolytic activity, and phytotoxicity in Pb(II)-contaminated soils was examined by the application of 4 different biochars to soil, with rice as a test plant. The FDA hydrolytic activities of biochar-amended soils were much higher than that of the control. The survival rate of rice in lead-contaminated biochar-amended soils showed significant improvement over the control, especially for bamboo biochar-amended soil (93.3%). In addition, rice grown in lead-contaminated control sediment displayed lower biomass production than that in biochar-amended soil. The immobilization of Pb(II) and the positive effects of biochar amendment on soil microorganisms may account for these effects. The results suggest that biochar may have an excellent ability to mitigate the toxic effects of Pb(II) on soil microorganisms and rice. © 2015 SETAC.

  8. Comparative analysis of copper and zinc based agrichemical biocide products: materials characteristics, phytotoxicity and in vitro antimicrobial efficacy

    Directory of Open Access Journals (Sweden)

    Harikishan Kannan

    2016-07-01

    Full Text Available In the past few decades, copper based biocides have been extensively used in food crop protection including citrus, small fruits and in all garden vegetable production facilities. Continuous and rampant use of copper based biocides over decades has led to accumulation of this metal in the soil and the surrounding ecosystem. Toxic levels of copper and its derivatives in both the soil and in the run off pose serious environmental and public health concerns. Alternatives to copper are in great need for the agriculture industry to produce food crops with minimal environmental risks. A combination of copper and zinc metal containing biocide such as Nordox 30/30 or an improved version of zinc-only containing biocide would be a good alternative to copper-only products if the efficacy can be maintained. As of yet there is no published literature on the comparative study of the materials characteristics and phyto-compatibility properties of copper and zinc-based commercial products that would allow us to evaluate the advantages and disadvantages of both versions of pesticides. In this report, we compared copper hydroxide and zinc oxide based commercially available biocides along with suitable control materials to assess their efficacy as biocides. We present a detailed material characterization of the biocides including morphological studies involving electron microscopy, molecular structure studies involving X-ray diffraction, phytotoxicity studies in model plant (tomato and antimicrobial studies involving surrogate plant pathogens (Xanthomonas alfalfae subsp. citrumelonis, Pseudomonas syringae pv. syringae and Clavibacter michiganensis subsp. michiganensis. Zinc based compounds were found to possess comparable to superior antimicrobial properties while exhibiting significantly lower phytotoxicity when compared to copper based products thus suggesting their potential as an alternative.

  9. Screening and identification of phytotoxic volatile compounds in medicinal plants and characterizations of a selected compound, eucarvone.

    Science.gov (United States)

    Sunohara, Yukari; Baba, Yohei; Matsuyama, Shigeru; Fujimura, Kaori; Matsumoto, Hiroshi

    2015-07-01

    Screening and identification of phytotoxic volatile compounds were performed using 71 medicinal plant species to find new natural compounds, and the characterization of the promising compound was investigated to understand the mode of action. The volatile compounds from Asarum sieboldii Miq. showed the strongest inhibitory effect on the hypocotyl growth of lettuce seedlings (Lactuca sativa L.cv. Great Lakes 366), followed by those from Schizonepeta tenuifolia Briquet and Zanthoxylum piperitum (L.) DC.. Gas chromatography-mass spectrometry (GC/MS) identified four volatile compounds, α-pinene (2,6,6-trimethylbicyclo[3.1.1]hept-2-ene), β-pinene (6,6-dimethyl-2-methylenebicyclo[3.1.1]heptane), 3-carene (3,7,7-trimethylbicyclo[4.1.0]hept-3-ene), and eucarvone (2,6,6-trimethy-2,4-cycloheptadien-1-one), from A. sieboldii, and three volatile compounds, limonene (1-methyl-4-(1-methylethenyl)-cyclohexene), menthone (5-methyl-2-(propan-2-yl)cyclohexan-1-one), and pulegone (5-methyl-2-propan-2-ylidenecyclohexan-1-one), from S. tenuifolia. Among these volatile compounds, eucarvone, menthone, and pulegone exhibited strong inhibitory effects on both the root and shoot growth of lettuce seedlings. Eucarvone-induced growth inhibition was species-selective. Cell death, the generation of reactive oxygen species (ROS), and lipid peroxidation were induced in susceptible finger millet seedlings by eucarvone treatment, whereas this compound (≤158 μM) did not cause the increase of lipid peroxidation and ROS production in tolerant maize. The results of the present study show that eucarvone can have strong phytotoxic activity, which may be due to ROS overproduction and subsequent oxidative damage in finger millet seedlings.

  10. Biodegradation of Azure-B dye by Serratia liquefaciens and its validation by phytotoxicity, genotoxicity and cytotoxicity studies.

    Science.gov (United States)

    Haq, Izharul; Raj, Abhay; Markandeya

    2018-04-01

    The azo dyes in textile industry are a major source of environmental pollution and cause serious threat to aquatic flora and fauna. The present study aims to evaluate the potential of previously isolated lignin peroxidase (LiP) enzyme producing Serratia liquefaciens in degradation of Azure-B (AB) dye. S. liquefaciens showed rapid decolourisation of AB dye (100 mg L -1 ) in mineral salt medium (MSM) supplemented with 0.2% glucose and yeast extract, and more than 90% dye decolourisation was observed at 48 h when incubated at 30 °C. Decolourisation conditions were optimized by Response Surface Methodology (RSM) using Box-Behnken Designs (BBD). The dye degradation was further confirmed by ATR-FTIR and GC-MS analysis. Toxicological studies of untreated (UT) and bacterial treated (BT) AB dye solutions were studied by using phytotoxicity, genotoxicity and cytotoxicity endpoints. Phytotoxicity assay using Vigna radiata indicated that bacterial treatment led to detoxification of AB dye. Genotoxicity assay with Allium cepa showed that pure AB dye solutions significantly reduced mitotic index (MI) and induced various chromosomal abnormalities (CAs) like c-mitosis, stickiness, chromosome break, anaphase bridges, vagrant chromosomes and binucleated and micronucleated cell in the root tip cells, whereas, bacterial treated solutions induced relatively less genotoxicity in nature. Improved cell survivability (%) was also noted in kidney cell line (NRK-52E) after S. liquefaciens treated dye solutions than the pure dye solutions. The findings suggest that S. liquefaciens could be a potential bacterium for azo dye degradation, as it is effective in lowering of toxic effects of AB dye. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Phytotoxic effects of Cu and Zn on soybeans grown in field-aged soils: their additive and interactive actions.

    Science.gov (United States)

    Kim, Bojeong; McBride, Murray B

    2009-01-01

    A field pot experiment was conducted to investigate the interactive phytotoxicity of soil Cu and Zn on soybean plants [Glycine max (L.) Merr.]. Two soils (Arkport sandy loam [coarse-loamy, mixed, active, mesic Lamellic Hapludalf] and Hudson silty clay loam [fine, illitic, mesic Glossaquic Hapludalf]) spiked with Cu, Zn, and combinations of both to reach the final soil metal range of 0 to 400 mg kg(-1) were tested in a 2-yr bioassay after 1 yr of soil-metal equilibration in the field. The soluble and easily-extractable fraction of soil Zn (or Cu), estimated by dilute CaCl2, increased linearly in response to the total Zn (or Cu) added. This linearity was, however, strongly affected where soils were treated with both metals in combination, most notably for Zn, as approximately 50% more of soil Zn was extracted into solution when the Cu level was high. Consequently, added Zn is less likely to be stabilized by aging than added Cu when both metals are present in field soils. The predictive model relating soil metal extractability to plant Zn concentration also revealed a significant Cu-Zn interaction. By contrast, the interaction between the two metals contributed little to explain plant Cu uptake. The additive action of soil Cu and Zn was of considerable importance in explaining plant biomass reduction. This work clearly demonstrates the critical roles of the properties of the soil, the nature of the metal, and the level of other toxic metals present on the development of differential phytotoxicity due to soil Cu and Zn.

  12. Getting the right grasp on executive function

    Directory of Open Access Journals (Sweden)

    Claudia L R Gonzalez

    2014-04-01

    Full Text Available Executive Function (EF refers to important socio-emotional and cognitive skills that are known to be highly correlated with both academic and life success. EF is a blanket term that is considered to include self-regulation, working memory, and planning. Recent studies have shown a relationship between EF and motor control. The emergence of motor control coincides with that of EF, hence understanding the relationship between these two domains could have significant implications for early detection and remediation of later EF deficits. The purpose of the current study was to investigate this relationship in young children. This study incorporated the Behavioural Rating Inventory of Executive Function (BRIEF and two motor assessments with a focus on precision grasping to test this hypothesis. The BRIEF is comprised of two indices of EF: 1 the Behavioral Regulation Index (BRI containing three subscales: Inhibit, Shift, and Emotional Control; 2 the Metacognition Index (MI containing five subscales: Initiate, Working Memory, Plan/Organize, Organization of Materials, and Monitor. A global executive composite (GEC is derived from the two indices. In this study, right-handed children aged 5-6 and 9-10 were asked to: grasp-to-construct (Lego® models; and grasp-to-place (wooden blocks, while their parents completed the BRIEF questionnaire. Analysis of results indicated significant correlations between the strength of right hand preference for grasping and numerous elements of the BRIEF including the BRI, MI, and GEC. Specifically, the more the right hand was used for grasping the better the EF ratings. In addition, patterns of space-use correlated with the GEC in several subscales of the BRIEF. Finally and remarkably, the results also showed a reciprocal relationship between hand and space use for grasping and EF. These findings are discussed with respect to: 1 the developmental overlap of motor and executive functions; 2 detection of EF deficits through

  13. Hot and cold executive functions in youth with psychotic symptoms.

    Science.gov (United States)

    MacKenzie, L E; Patterson, V C; Zwicker, A; Drobinin, V; Fisher, H L; Abidi, S; Greve, A N; Bagnell, A; Propper, L; Alda, M; Pavlova, B; Uher, R

    2017-12-01

    Psychotic symptoms are common in children and adolescents and may be early manifestations of liability to severe mental illness (SMI), including schizophrenia. SMI and psychotic symptoms are associated with impairment in executive functions. However, previous studies have not differentiated between 'cold' and 'hot' executive functions. We hypothesized that the propensity for psychotic symptoms is specifically associated with impairment in 'hot' executive functions, such as decision-making in the context of uncertain rewards and losses. In a cohort of 156 youth (mean age 12.5, range 7-24 years) enriched for familial risk of SMI, we measured cold and hot executive functions with the spatial working memory (SWM) task (total errors) and the Cambridge Gambling Task (decision-making), respectively. We assessed psychotic symptoms using the semi-structured Kiddie Schedule for Affective Disorders and Schizophrenia interview, Structured Interview for Prodromal Syndromes, Funny Feelings, and Schizophrenia Proneness Instrument - Child and Youth version. In total 69 (44.23%) youth reported psychotic symptoms on one or more assessments. Cold executive functioning, indexed with SWM errors, was not significantly related to psychotic symptoms [odds ratio (OR) 1.36, 95% confidence interval (CI) 0.85-2.17, p = 0.204). Poor hot executive functioning, indexed as decision-making score, was associated with psychotic symptoms after adjustment for age, sex and familial clustering (OR 2.37, 95% CI 1.25-4.50, p = 0.008). The association between worse hot executive functions and psychotic symptoms remained significant in sensitivity analyses controlling for general cognitive ability and cold executive functions. Impaired hot executive functions may be an indicator of risk and a target for pre-emptive early interventions in youth.

  14. Rheem: Enabling Multi-Platform Task Execution

    KAUST Repository

    Agrawal, Divy; Kruse, Sebastian; Ouzzani, Mourad; Papotti, Paolo; Quiane-Ruiz, Jorge-Arnulfo; Tang, Nan; Zaki, Mohammed J.; Ba, Lamine; Berti-Equille, Laure; Chawla, Sanjay; Elmagarmid, Ahmed; Hammady, Hossam; Idris, Yasser; Kaoudi, Zoi; Khayyat, Zuhair

    2016-01-01

    Many emerging applications, from domains such as healthcare and oil & gas, require several data processing systems for complex analytics. This demo paper showcases Rheem, a framework that provides multi-platform task execution for such applications. It features a three-layer data processing abstraction and a new query optimization approach for multi-platform settings. We will demonstrate the strengths of Rheem by using real-world scenarios from three different applications, namely, machine learning, data cleaning, and data fusion. © 2016 ACM.

  15. Rheem: Enabling Multi-Platform Task Execution

    KAUST Repository

    Agrawal, Divy

    2016-06-16

    Many emerging applications, from domains such as healthcare and oil & gas, require several data processing systems for complex analytics. This demo paper showcases Rheem, a framework that provides multi-platform task execution for such applications. It features a three-layer data processing abstraction and a new query optimization approach for multi-platform settings. We will demonstrate the strengths of Rheem by using real-world scenarios from three different applications, namely, machine learning, data cleaning, and data fusion. © 2016 ACM.

  16. Subjective executive difficulties – a study using the Dysexecutive Questionnaire

    Directory of Open Access Journals (Sweden)

    Ewa Małgorzata Szepietowska

    2018-03-01

    Full Text Available Introduction: Subjective executive difficulties, understood as a sense of disruption of planning, control and correction of one’s own activity, is often reported by healthy as well as clinical individuals. Self-report measures such as the Dysexecutive Questionnaire (DEX-S are used to assess the severity of this feeling. The diagnostic value of this method is debated due to the numerous factors affecting the beliefs on executive deficits. Aim of the study: With reference to inconclusive data concerning the underlying factors of subjective executive deficits and the value of self-report measures the following aims of the present study were established: a determination of the demographic, clinical and cognitive characteristics of individuals with various levels of subjective executive difficulties, b finding which of these variables contribute to the risk of subjective executive difficulties increase. Material and methods: The study included 213 adult individuals. DEX-S as well as measures of cognitive assessment (Montreal Cognitive Assessment, MoCA; subtests of the Wechsler Adult Intelligence Scale-Revised, WAIS-R and depressive mood assessment [Geriatric Depression Scale (Short Form, GDS-15] were used. Demographic variables (age, gender and educational level as well as clinical variables (lack of/presence of central nervous system disease history, including lateralised brain pathology were also taken into consideration. Based on DEX-S results a cluster analysis was performed and two groups of subjects with a different level of subjective executive difficulties were identified: low-severity group (individuals reporting no complaints regarding executive deficits and high-severity group (individuals with complaints. Group comparisons demonstrated that individuals complaining about executive deficits have a higher depressive mood index and lower scores on some subtests used to assess cognitive functions. The results of logistic regression analysis

  17. Supramodal Executive Control of Attention

    Directory of Open Access Journals (Sweden)

    ALFREDO eSPAGNA

    2015-02-01

    Full Text Available The human attentional system can be subdivided into three functional networks of alerting, orienting, and executive control. Although these networks have been extensively studied in the visuospatial modality, whether the same mechanisms are deployed across different sensory modalities remains unclear. In this study we used the attention network test for visuospatial modality, in addition to two auditory variants with spatial and frequency manipulations to examine cross-modal correlations between network functions. Results showed that among the visual and auditory tasks the effects of executive control, but not effects of alerting and orienting were significantly correlated. These findings suggest that while alerting and orienting functions rely more upon modality specific processes, the executive control of attention coordinates complex behavior via supramodal mechanisms.

  18. Executive Headteachers: What's in a Name? Executive Summary

    Science.gov (United States)

    Theobald, Katy; Lord, Pippa

    2016-01-01

    Executive headteachers (EHTs) are becoming increasingly prevalent as the self-improving school system matures; there are over 620 EHTs in the school workforce today; and the number recorded in the School Workforce Census (SWC) has increased by 240 per cent between 2010 and 2014. The role is still evolving locally and nationally and, as EHTs take…

  19. ADAMS executive and operating system

    Science.gov (United States)

    Pittman, W. D.

    1981-01-01

    The ADAMS Executive and Operating System, a multitasking environment under which a variety of data reduction, display and utility programs are executed, a system which provides a high level of isolation between programs allowing them to be developed and modified independently, is described. The Airborne Data Analysis/Monitor System (ADAMS) was developed to provide a real time data monitoring and analysis capability onboard Boeing commercial airplanes during flight testing. It inputs sensor data from an airplane performance data by applying transforms to the collected sensor data, and presents this data to test personnel via various display media. Current utilization and future development are addressed.

  20. Executive Functioning in Participants Over Age of 50 with Hoarding Disorder.

    Science.gov (United States)

    Ayers, Catherine R; Dozier, Mary E; Wetherell, Julie Loebach; Twamley, Elizabeth W; Schiehser, Dawn M

    2016-05-01

    The current investigation utilized mid-life and late-life participants diagnosed with hoarding disorder (HD) to explore the relationship between executive functioning and hoarding severity. Correlational analyses were used to investigate the associations between executive functioning and hoarding severity in nondemented participants. Multiple regression was used to determine if executive functioning had a unique association with HD severity when accounting for depressive symptoms. Participants were recruited from the San Diego area for HD intervention studies. Participants were 113 nondemented adults aged 50-86 years who met DSM-5 criteria for HD. The mean age of the sample utilized in the analyses was 63.76 years (SD, 7.2; range, 51-85 years). The sample was mostly female (72%), Caucasian (81.4%), and unmarried (78%). Hoarding severity was assessed using the Saving Inventory-Revised and the Clutter Image Rating and depression was assessed using the Hospital Anxiety and Depression Scale. Executive functioning was assessed using the Wisconsin Card Sorting Test (WCST-128) and the Trail Making and Verbal Fluency subtests of the Delis-Kaplan Executive Function System. Executive function (operationalized as perseveration on the WCST-128) was significantly associated with Clutter Image Ratings. In a multivariate context, executive function and depressive symptom severity were both significant predictors of variance in Clutter Image Rating. Our results suggest that executive function is related to severity of HD symptoms and should be considered as part of the conceptualization of HD. Published by Elsevier Inc.

  1. Chemical characterization by GC-MS and phytotoxic potential of non-polar and polar fractions of seeds of Dioteryx odorata (Aubl. Willd. from Venezuelan regions

    Directory of Open Access Journals (Sweden)

    Alberto de J. Oliveros-Bastidas

    2013-01-01

    Full Text Available Dipteryx odorata (Aubl. Willd. is a tall arboreal species native to Central and Northern South America. This paper describes the chemical characterization and phytotoxic potential of polar and non-polar extracts from D. odorata seeds. Structural determinations were accomplished by chemical derivatization and analyzed by GC/MS. The chemical composition of the non-polar fraction (hexane and dichloromethane presented fatty acids as major constituent. Medium polar and polar fractions (ethyl acetate and ethanol: water contained carboxylic acid and high 6,7-Dyhidroxycoumarin-β-D-glucopyranoside content, not previously reported for seeds of D. odorata. Extracts showed a significant level of phytotoxic activity, correlated to the content of coumarin derivatives, predominantly in the polar fraction.

  2. Antifungal and phytotoxic activity of essential oil from root of Senecio amplexicaulis Kunth. (Asteraceae) growing wild in high altitude-Himalayan region.

    Science.gov (United States)

    Singh, Rajendra; Ahluwalia, Vivek; Singh, Pratap; Kumar, Naresh; Prakash Sati, Om; Sati, Nitin

    2016-08-01

    This work was aimed to evaluate the essential oil from root of medicinally important plant Senecio amplexicaulis for chemical composition, antifungal and phytotoxic activity. The chemical composition analysed by GC/GC-MS showed the presence of monoterpene hydrocarbons in high percentage with marker compounds as α-phellandrene (48.57%), o-cymene (16.80%) and β-ocimene (7.61%). The essential oil exhibited significant antifungal activity against five phytopathogenic fungi, Sclerotium rolfsii, Macrophomina phaseolina, Rhizoctonia solani, Pythium debaryanum and Fusarium oxysporum. The oil demonstrated remarkable phytotoxic activity in tested concentration and significant reduction in seed germination percentage of Phalaris minor and Triticum aestivum at higher concentrations. The roots essential oil showed high yield for one of its marker compound (α-phellandrene) which makes it important natural source of this compound.

  3. Development of a scale of executive functioning for the RBANS.

    Science.gov (United States)

    Spencer, Robert J; Kitchen Andren, Katherine A; Tolle, Kathryn A

    2018-01-01

    The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is a cognitive battery that contains scales of several cognitive abilities, but no scale in the instrument is exclusively dedicated to executive functioning. Although the subtests allow for observation of executive-type errors, each error is of fairly low base rate, and healthy and clinical normative data are lacking on the frequency of these types of errors, making their significance difficult to interpret in isolation. The aim of this project was to create an RBANS executive errors scale (RBANS EE) with items comprised of qualitatively dysexecutive errors committed throughout the test. Participants included Veterans referred for outpatient neuropsychological testing. Items were initially selected based on theoretical literature and were retained based on item-total correlations. The RBANS EE (a percentage calculated by dividing the number of dysexecutive errors by the total number of responses) was moderately related to each of seven established measures of executive functioning and was strongly predictive of dichotomous classification of executive impairment. Thus, the scale had solid concurrent validity, justifying its use as a supplementary scale. The RBANS EE requires no additional administration time and can provide a quantified measure of otherwise unmeasured aspects of executive functioning.

  4. Proverb comprehension impairments in schizophrenia are related to executive dysfunction.

    Science.gov (United States)

    Thoma, Patrizia; Hennecke, Marie; Mandok, Tobias; Wähner, Alfred; Brüne, Martin; Juckel, Georg; Daum, Irene

    2009-12-30

    The study aimed to investigate the pattern of proverb comprehension impairment and its relationship to proverb familiarity and executive dysfunction in schizophrenia. To assess the specificity of the impairment pattern to schizophrenia, alcohol-dependent patients were included as a psychiatric comparison group, as deficits of executive function and theory of mind as well as dysfunction of the prefrontal cortex, which have been related to proverb comprehension difficulties, are common in both disorders. Twenty-four schizophrenia patients, 20 alcohol-dependent patients and 34 healthy controls were administered a multiple-choice proverb interpretation task incorporating ratings of subjective familiarity and measures of executive function. Schizophrenia patients chose the correct abstract and meaningful interpretations less frequently and instead chose the incorrect concrete (both meaningless and meaningful) proverb interpretations more often than alcohol-dependent patients and healthy controls. Relative to healthy controls, schizophrenia patients also chose more abstract-meaningless response alternatives and were impaired in all executive domains. Impaired divided attention was most consistently associated with proverb interpretation deficits in both patient groups. Taken together, schizophrenia patients showed a specific pattern of proverb comprehension impairments related to executive dysfunction and symptoms. The comparison with the alcohol-dependent subgroup suggests that a more comprehensive and severe impairment of complex higher-order cognitive functions including executive behavioural control and non-literal language comprehension might be associated with frontal dysfunction in schizophrenia as compared to alcohol use disorder.

  5. Executive and Memory Function in Adolescents Born Very Preterm

    Science.gov (United States)

    Ment, Laura; Allan, Walter; Schneider, Karen; Vohr, Betty R.

    2011-01-01

    BACKGROUND: Many preterm children display school difficulties, which may be mediated by impairment in executive function and memory. OBJECTIVE: To evaluate executive and memory function among adolescents born preterm compared with term controls at 16 years. METHODS: A total of 337 of 437 (77%) adolescents born in 1989 to 1992 with a birth weight executive function and memory tasks. Multiple regression analyses were used to compare groups and to identify associations between selected factors and outcomes among preterm subjects. RESULTS: Adolescents born preterm, compared with term controls, showed deficits in executive function in the order of 0.4 to 0.6 SD on tasks of verbal fluency, inhibition, cognitive flexibility, planning/organization, and working memory as well as verbal and visuospatial memory. After exclusion of adolescents with neurosensory disabilities and full-scale IQ executive dysfunction, as measured with the Behavior Rating Inventory of Executive Function, on the Metacognition Index (odds ratio [OR]: 2.5 [95% confidence interval (CI): 1.2–5.1]) and the Global Executive Composite (OR: 4.2 [95% CI: 1.6–10.9]), but not on the Behavioral Regulation index (OR: 1.5 [95% CI: 0.7–3.5]). Among adolescents born preterm, severe brain injury on neonatal ultrasound and lower maternal education were the most consistent factors associated with poor outcomes. CONCLUSIONS: Even after exclusion of preterm subjects with significant disabilities, adolescents born preterm in the early 1990s were at increased risk of deficits in executive function and memory. PMID:21300680

  6. Synthesis of Digital Microfluidic Biochips with Reconfigurable Operation Execution

    DEFF Research Database (Denmark)

    Maftei, Elena

    several real-life case studies and synthetic benchmarks. The experiments show that by considering the dynamically reconfigurable nature of microfluidic operations, significant improvements can be obtained, decreasing the biochemical application completion times, reducing thus the biochip area...... of electrodes. The main objective of this thesis is to develop top-down synthesis techniques for digital microfluidic biochips. So far, researchers have assumed that operations are executing on virtual modules of rectangular shape, formed by grouping adjacent electrodes, and which have a fixed placement...... on the microfluidic array. However, operations can actually execute by routing the droplets on any sequence of electrodes on the biochip. Thus, we have proposed a routing-based model of operation execution, and we have developed several associated synthesis approaches, which progressively relax the assumption...

  7. Executive Summary - Future plans

    International Nuclear Information System (INIS)

    2005-01-01

    Our Institute has sufficient scientific potential to play a key role in the field of particle physics, nuclear physics and in several aspects of solid state and applied physics, at least in our part of Europe. We believe the Institute should continue its present mode of operation, where basic research, closely coordinated through our collaboration with leading laboratories all over the world, stimulates our interdisciplinary research and technology transfer to the industry. If our present scientific potential is matched by suitably modernized infrastructure, we should be able to acquire the critical mass necessary for further effective development. In order to maintain our present world-level research, we have to continue and further extend our participation in large international collaborations, in the construction of large detectors and to seek further financial support from EU and international organizations. For experimental particle physics, our priorities remain in collaborating with major European and world laboratories such as CERN, DESY, Gran Sasso, Fermilab, KEK, SLAC and with laboratories developing astrophysics experiments, such as the PIERRE AUGER experiment. Collaboration in the field of nuclear physics, physics of condensed matter, theoretical physics and interdisciplinary research should be continued with leading European laboratories offering access to large accelerator facilities (such as GANIL or GSI), to synchrotron radiation or to unique polarized neutron beams, such as those available at ILL Grenoble. An exiting new frontier in research for our research teams will be opened by the X-ray Free Electron Laser (XFEL) in DESY and the future International Linear Collider. We will be able to further invest towards upgrading our small-scale facilities, such as the infrastructure around the Van de Graaff accelerator, in order to perform single-ion beam experiments, or around the AIC-144 cyclotron, to treat ocular melanoma, in close collaboration with

  8. Cannabinoid modulation of executive functions

    NARCIS (Netherlands)

    Pattij, T.; Wiskerke, J.; Schoffelmeer, A.N.M.

    2008-01-01

    Executive functions are higher-order cognitive processes such as attention, behavioural flexibility, decision-making, inhibitory control, planning, time estimation and working memory that exert top-down control over behaviour. In addition to the role of cannabinoid signaling in other cognitive

  9. Antifungal, phytotoxic and insecticidal properties of essential oil isolated from Turkish Origanum acutidens and its three components, carvacrol, thymol and p-cymene.

    Science.gov (United States)

    Kordali, Saban; Cakir, Ahmet; Ozer, Hakan; Cakmakci, Ramazan; Kesdek, Memis; Mete, Ebru

    2008-12-01

    The chemical composition of essential oil isolated by hydrodistillation from the aerial parts of Origanum acutidens was analyzed by GC-MS. Carvacrol (87.0%), p-cymene (2.0%), linalool acetate (1.7%), borneol (1.6%) and beta-caryophyllene (1.3%) were found to be as main constituents. Antifungal, phytotoxic and insecticidal activities of the oil and its aromatic monoterpene constituents, carvacrol, p-cymene and thymol were also determined. The antifungal assays showed that O. acutidens oil, carvacrol and thymol completely inhibited mycelial growth of 17 phytopathogenic fungi and their antifungal effects were higher than commercial fungicide, benomyl. However, p-cymene possessed lower antifungal activity. The oil, carvacrol and thymol completely inhibited the seed germination and seedling growth of Amaranthus retroflexus, Chenopodium album and Rumex crispus and also showed a potent phytotoxic effect against these plants. However, p-cymene did not show any phytotoxic effect. Furthermore, O. acutidens oil showed 68.3% and 36.7% mortality against Sitophilus granarius and Tribolium confusum adults, respectively. The findings of the present study suggest that antifungal and herbicidal properties of the oil can be attributed to its major component, carvacrol, and these agents have a potential to be used as fungicide, herbicide as well as insecticide.

  10. HEAO Block 2 study executive summary

    International Nuclear Information System (INIS)

    1976-03-01

    An executive summary is presented of a preliminary study done on several potential High Energy Astronomy Observatory (HEAO) missions which are follow-on missions to the currently defined HEAO program. The purpose was to examine several typical missions and determine the relative complexities associated with them. The four payloads investigated were a 1.2 m Diameter x-ray Telescope observatory, a Large Area Moderate Angular Resolution (LAMAR) observatory, a cosmic ray observatory, and (4) a gamma ray observatory. Each of the four observatories was considered a national facility. Low cost approaches were stressed throughout, with considerable use of HEAO Block I experience and designs effected to provide a high degree of confidence that such approaches were achievable. The use of the Multi-Mission Spacecraft (MMS) and the HEAO Block I spacecraft was considered as a result of this low cost emphasis. Also, NASA standard components were considered, where applicable

  11. Executive Summary - Historical background

    International Nuclear Information System (INIS)

    2005-01-01

    The Institute of Nuclear Physics (INP) was established in Cracow in 1955. The post-war excitement of engaging in scientific activity, can certainly be credited to the talent, experience and unusual personality of Professor Henryk Niewodniczanski, the founder and first Director of the INP. In the 60's the INP research activity was concentrated around the Russian U120 Cyclotron, built in 1958 which provided deuteron beams up to 14.5 MeV and of alpha particles up to 29 MeV. A small 48 cm pole-piece cyclotron with was in-house constructed, and used for PIXE analyses and RBA material studies. In 1960's, the nuclear spectroscopy group began building several types of magnetic beta ray spectrometers to study excited levels of neutron-deficient isotopes provided by the 660 MeV cyclotron of the JINR. In parallel, studies of spin polarization of n and p emitted in the deuteron stripping reaction were performed. Studies of condensed matter using pulsed neutron beams from the IBR30 and Kjeller (Norway) reactors had also began. The NMR signal was first observed in Poland by physicists from the Jagiellonian University, and a well equipped NMR Laboratory was also created at the INP. A small theoretical physics department was established to support experimental research. Applied physics, based on the research performed in the INP was also developed. Following the interest in fast neutron radiotherapy, initiated by the Gray Laboratory in Hammersmith, a beam of fast neutrons was produced on a Be target by 13.5 MeV deuterons from the U120 and applied for cancer therapy, in a collaborative effort with the Centre of Oncology in Cracow. Over a period of 10 years, some 500 patients were treated, in selected types of salivary gland cancer and post-mastectomy recurrences. In the late 60's a technology of thermoluminescent dosimeters (TLD) was developed at the INP, based on specially activated LiF. The method was patented and TLDs, manufactured at the INP, are nowadays applied by in over 30

  12. Executive Summary - Overview

    International Nuclear Information System (INIS)

    2005-01-01

    specialised physics topics are given to 55 students of the International Post-Graduate Study Course at the IFJ. These courses are attended by students from universities of several countries

  13. Comparative antimicrobial, phytotoxic and heamaglutination potential of eriobotrya japonica leaf extract and its zinc nano-particles

    International Nuclear Information System (INIS)

    Aziz, A.; Khan, I.; Azam, S.; Mehnaz, S.; Ahmad, B.

    2017-01-01

    The aim of the current study was to synthesize Zinc nanoparticles (ZnNPs) of Eriobotrya japonica, their characterization using standard procedures and its screening for various pharmacological activities; antibacterial, antifungal, phytotoxic and heamaglutination in comparison with the methanolic, ethanolic and Ethyl acetate (EtOAc) fractions. The UV-Visible absorption spectra of ZnNPs showed peaks at 455 nm and Fourier Transform Infrared spectroscopy (FTIR) confirmed the presence of various functional groups such as, hydroxyl, amide, carbonyl, aldehyde, and alkynes. The Scanning Electron Microscope (SEM) analysis showed that the particle size was between 30-60 nm with spherical shape. The presence of Zinc along with other elements, such as C, O, S, Si, and K, was confirmed by Energy Dispersive X-ray (EDX), andthe mean size was 33nm as indicated in X-ray diffraction (XRD) spectra. The results of percent antibacterial activity for the methanolic, ethanolic and EtOAc fractions of E. japonica against E. coli was 62, 59.2, 44.4, P. aeruginosa 44.4, 40.7, 37, S. aureus 69.2, 46.1, 50, A. baumannii 52.1, 43.4, 0, M. morganii 59, 40.9, 68, MRSA 73.6, 52.6, 0 and P. vulgaris 60, 52, 64. The Zn NPs exhibited significant antibacterial activity against MRSA (94%) and P. vulgaris (92%), good against S. aureus (73%) and M. morganii (63.6%), moderate against E. coli (48.1%) and A. baumannii (43.4%) and low against P. aeruginosa (37%), respectively. The methanolic, ethanolic and EtOAc fractions of E. japonica showed low (<24%) and no antifungal activity against the tested fungal pathogens. The antifungal activity of Zn NPs against the test fungal pathogens was; A. parasiticus (30%), P. notatum and A. niger (40%), P. chrysogenum (55%), H. pseudocrispula (60%) while it was inactive against V. longisporum. The methanolic, ethanolic and EtOAc extract of E. japonica showed 50, 50 and 60% growth regulation at 1000, 50, 40 and 60% at 100 µg/ml, while at 10 µg/ml, 40, 20 and 50

  14. Execute-Only Attacks against Execute-Only Defenses

    Science.gov (United States)

    2016-02-18

    strongest implementations of execute-only defenses: it exploits novel hardware features to incorporate non-readable code to prevent direct information...build two proof-of- concept exploits that can achieve control flow hijacking on a system protected by full- featured Readactor. • We evaluate the...According to the CVE [31], 123 such arbitrary read vulnerabilities were reported between January and September of 2015, in Firefox (CVE-2015-4495

  15. Executive functioning in adult ADHD: a meta-analytic review

    NARCIS (Netherlands)

    Boonstra, A.M.; Oosterlaan, J.; Sergeant, J.A.; Buitelaar, J.K.

    2005-01-01

    Background. Several theoretical explanations of ADHD in children have focused on executive functioning as the main explanatory neuropsychological domain for the disorder. In order to establish if these theoretical accounts are supported by research data for adults with ADHD, we compared

  16. Vectorization vs. compilation in query execution

    NARCIS (Netherlands)

    J. Sompolski (Juliusz); M. Zukowski (Marcin); P.A. Boncz (Peter)

    2011-01-01

    textabstractCompiling database queries into executable (sub-) programs provides substantial benefits comparing to traditional interpreted execution. Many of these benefits, such as reduced interpretation overhead, better instruction code locality, and providing opportunities to use SIMD

  17. ARC Code TI: IPG Execution Service

    Data.gov (United States)

    National Aeronautics and Space Administration — The Execution Service allows users to submit, monitor, and cancel complex jobs. Each job consists of a set of tasks that perform actions such as executing...

  18. Executive Functions and Working Memory Behaviours in Children with a Poor Working Memory

    Science.gov (United States)

    St. Clair-Thompson, Helen L.

    2011-01-01

    Previous research has suggested that working memory difficulties play an integral role in children's underachievement at school. However, working memory is just one of several executive functions. The extent to which problems in working memory extend to other executive functions is not well understood. In the current study 38 children with a poor…

  19. Test Review: Behavior Rating Inventory of Executive Function--Self-Report Version

    Science.gov (United States)

    Walker, Justin M.; D'Amato, Rik Carl

    2006-01-01

    The Behavior Rating Inventory of Executive Function-Self-Report version (BRIEF-SR) is the first self-report measure of executive functioning for adolescents. With the Individuals With Disabilities Education Improvement Act authorization, there is a greater need for appropriate assessment of severely impaired children. Recent studies have…

  20. Rehabilitation of executive functions: Implications and strategies

    Directory of Open Access Journals (Sweden)

    Bruno Kluwe-Schiavon

    2013-01-01

    Full Text Available Executive Functions (EF concern a range of abilities including problem-solving, planning, initiation, selfmonitoring,conscious attention, cope with new situations and the ability to modify plans if necessary. It’s a high cognitive function that is crucial for a person to get engaged and maintain daily activities whilst keeping a good quality of life. Problems in the EF were formerly known as Dysexecutive Syndrome (DS. There are many models concerning DS, although the literature on the subject still remains unclear. Several works appoint the effects brought by elderly life, as well as abuse of drugs and some psychopathologies. These factors are known to increase the distress of the frontal circuits and that could be associated to executive deficits. The effects of DS would compromise individuals in day-to-day routine, academic, social and labor fields. There is a growing body of studies trying to determine the causes, implications, associations and the best way to take care of these effects. This work intends to review DS, focusing on the most important fields related to this area, such as psychopathology associations, cognitive reserve, assessment and cognitive rehabilitation programs.

  1. Executable Operational Semantics of Solidity

    OpenAIRE

    Jiao, Jiao; Kan, Shuanglong; Lin, Shang-Wei; Sanan, David; Liu, Yang; Sun, Jun

    2018-01-01

    Bitcoin has attracted everyone's attention and interest recently. Ethereum (ETH), a second generation cryptocurrency, extends Bitcoin's design by offering a Turing-complete programming language called Solidity to develop smart contracts. Smart contracts allow creditable execution of contracts on EVM (Ethereum Virtual Machine) without third parties. Developing correct smart contracts is challenging due to its decentralized computation nature. Buggy smart contracts may lead to huge financial lo...

  2. Executive compensation: a calibration approach

    OpenAIRE

    Ivilina Popova; Joseph G. Haubrich

    1998-01-01

    We use a version of the Grossman and Hart principal-agent model with 10 actions and 10 states to produce quantitative predictions for executive compensation. Performance incentives derived from the model are compared with the performance incentives of 350 firms chosen from a survey by Michael Jensen and Kevin Murphy. The results suggest both that the model does a reasonable job of explaining the data and that actual incentives are close to the optimal incentives predicted by theory.

  3. 36th ATLANTA EXECUTIVE SEMINAR

    Science.gov (United States)

    2011-04-04

    assignments as an Army Division G-4, Divisional Support Battalion Commander, Divisional Material Readiness officer, and Support Battalion Executive...Battalion; Corps Material Management Officer, Corps Support Command; Fort Hood, Texas • Jul 1991 – Jun 1994: Research Analyst, Office of Economic and...LABBLEE Corp, Raytheon, Labat-Anderson Inc., KPMG , Huber Corp, The Boeing Company, and Philadelphia Electric Company. He has also served on a

  4. Financial accounting for radiology executives.

    Science.gov (United States)

    Seidmann, Abraham; Mehta, Tushar

    2005-03-01

    The authors review the role of financial accounting information from the perspective of a radiology executive. They begin by introducing the role of pro forma statements. They discuss the fundamental concepts of accounting, including the matching principle and accrual accounting. The authors then explore the use of financial accounting information in making investment decisions in diagnostic medical imaging. The paper focuses on critically evaluating the benefits and limitations of financial accounting for decision making in a radiology practice.

  5. Executive pay and shareholder litigation

    OpenAIRE

    Lin Peng; Ailsa Röell

    2008-01-01

    The paper examines the impact of executive compensation on private securities litigation. We find that incentive pay in the form of options increases the probability of securities class action litigation, holding constant a wide range of firm characteristics. We further document that there is abnormal upward earnings manipulation during litigation class periods and that insiders exercise more options and sell more shares during class periods, but that this activity is largely driven by pre-ex...

  6. Changes in Phenolic Compounds and Phytotoxicity of the Spanish-Style Green Olive Processing Wastewaters by Aspergillus niger B60.

    Science.gov (United States)

    Papadaki, Eugenia; Tsimidou, Maria Z; Mantzouridou, Fani Th

    2018-05-16

    This study systematically investigated the degradation kinetics and changes in the composition of phenolic compounds in Spanish-style Chalkidiki green olive processing wastewaters (TOPWs) during treatment using Aspergillus niger B60. The fungal growth and phenol degradation kinetics were described sufficiently by the Logistic and Edward models, respectively. The maximum specific growth rate (2.626 1/d) and the maximum degradation rate (0.690 1/h) were observed at 1500 mg/L of total polar phenols, indicating the applicability of the process in TOPWs with a high concentration of phenolic compounds. Hydroxytyrosol and the other simple phenols were depleted after 3-8 days. The newly formed secoiridoid derivatives identified by HPLC-DAD-FLD and LC-MS are likely produced by oleoside and oleuropein aglycon via the action of fungal β-glucosidase and esterase. The treated streams were found to be less phytotoxic with reduced chemical oxygen demand by up to 76%. Findings will provide useful information for the subsequent treatment of residual contaminants.

  7. Mobile organic compounds in biochar - a potential source of contamination - phytotoxic effects on cress seed (Lepidium sativum) germination.

    Science.gov (United States)

    Buss, Wolfram; Mašek, Ondřej

    2014-05-01

    Biochar can be contaminated during pyrolysis by re-condensation of pyrolysis vapours. In this study two biochar samples contaminated by pyrolysis liquids and gases to a high degree, resulting in high volatile organic compound (high-VOC) content, were investigated and compared to a biochar with low volatile organic compound (low-VOC) content. All biochar samples were produced from the same feedstock (softwood pellets) under the same conditions (550 °C, 20 min mean residence time). In experiments where only gaseous compounds could access germinating cress seeds (Lepidium sativum), application amounts ranging from 1 to 30 g of high-VOC biochar led to total inhibition of cress seed germination, while exposure to less than 1 g resulted in only partial reduction. Furthermore, leachates from biochar/sand mixtures (1, 2, 5 wt.% of biochar) induced heavy toxicity to germination and showed that percolating water could dissolve toxic compounds easily. Low-VOC biochar didn't exhibit any toxic effects in either germination test. Toxicity mitigation via blending of a high-VOC biochar with a low-VOC biochar increased germination rate significantly. These results indicate re-condensation of VOCs during pyrolysis can result in biochar containing highly mobile, phytotoxic compounds. However, it remains unclear, which specific compounds are responsible for this toxicity and how significant re-condensation in different pyrolysis units might be. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Phytotoxic effects of nickel on yield and concentration of macro- and micro-nutrients in sunflower (Helianthus annuus L.) achenes.

    Science.gov (United States)

    Ahmad, Muhammad Sajid Aqeel; Ashraf, Muhammad; Hussain, Mumtaz

    2011-01-30

    The phytotoxic effects of varying levels of nickel (0, 10, 20, 30, and 40 mg L(-1)) on growth, yield and accumulation of macro- and micro-nutrients in leaves and achenes of sunflower (Helianthus annuus L.) were appraised in this study. A marked reduction in root and shoot fresh biomass was recorded at higher Ni levels. Nickel stress also caused a substantial decrease in all macro- and micro-nutrients in leaves and achenes. The lower level of Ni (10 mg L(-1)) had a non-significant effect on various yield attributes, but higher Ni levels considerably decreased these parameters. Higher Ni levels decreased the concentrations of Ca, Mn and Fe in achenes. In contrast, achene N, K, Zn, Mn and Cu decreased consistently with increasing level of Ni, even at lower level (10 mg L(-1)). Sunflower hybrid Hysun-33 had better yield and higher most of the nutrients in achenes as compared with SF-187. The maximum reduction in all parameters was observed at the maximum level of nickel (40 mg L(-1)) where almost all parameters were reduced more than 50% of those of control plants. In conclusion, the pattern of uptake and accumulation of different nutrients in sunflower plants were nutrient- and cultivar-specific under Ni-stress. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Treated wastewater phytotoxicity assessment using Lactuca sativa: Focus on germination and root elongation test parameters.

    Science.gov (United States)

    Priac, Anne; Badot, Pierre-Marie; Crini, Grégorio

    2017-03-01

    Sensitive and simple ecotoxicological bioassays like seed germination and root elongation tests are commonly used to evaluate the phytotoxicity of waste and industrial discharge waters. Although the tests are performed following national and international standards, various parameters such as the number of seeds per dish, the test duration or the type of support used remain variable. To be able to make a correct comparison of results from different studies, it is crucial to know which parameter(s) could affect ecotoxicological diagnosis. We tested four different control waters and three seed densities. No significant differences on either germination rate or root elongation endpoints were shown. Nevertheless, we found that the four lettuce cultivars (Appia, batavia dorée de printemps, grosse blonde paresseuse, and Kinemontepas) showed significantly different responses when watered with the same and different metal-loaded industrial discharge water. From the comparison, it is clear that a differential sensitivity scale occurs among not just species but cultivars. Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

  10. Phytotoxicity of organic extracts of Turnera ulmifolia L. and Turnera diffusa Willd. ex Schult. in cucumber seeds

    Directory of Open Access Journals (Sweden)

    Daniel Moreto Silvestre

    2013-09-01

    Full Text Available We evaluated the phytotoxic effects that the hexane, ethyl acetate and methanol extracts from leaves and branches of the species Turnera ulmifolia L. and Turnera diffusa Willd. ex Schult. (Turneraceae, at concentrations of 1.25, 2.50, 3.75 and 5.00 mg ml-1, have on seed germination and seedling development in cucumber (Cucumis sativus L.. None of the extracts tested prevented germination, although the ethyl acetate extracts of T. diffusa, at 3.75 and 5.00 mg ml-1, reduced the mean germination speed and time to germination. Hexane extracts of both species reduced the main root length, number of secondary roots and hypocotyl length. In the ethyl acetate and methanol extracts, the number of secondary roots and hypocotyl length varied by species and concentration. Ethyl acetate extracts of T. ulmifolia at 2.50 mg ml-1. Comparatively, T. diffusa extracts inhibited development to a greater degree, thus presenting greater allelopathic potential, than did T. ulmifolia extracts.

  11. Phytotoxicity of ethanolic extracts of fruits and leaves of Banisteriopsis oxyclada (A. Juss. B. Gates on weeds growth

    Directory of Open Access Journals (Sweden)

    Simoni Anese

    2016-02-01

    Full Text Available This study aimed to evaluate the effect of ethanolic extract of leaves and fruits of Banisteriopsis oxyclada on seedling growth of wild poinsettia and barnyardgrass. Crude ethanolic extract was prepared at a proportion of 100 g of dry plant matter for 500 mL of ethanol. Through this, the extracts were solubilized in buffer solution and dimethyl sulfoxide (DMSO, at the concentrations 10.0; 7.5; 5.0; and 2.5 mg/mL. The growth of roots, shoots, and seedling root metaxylem cells were evaluated. Ethanolic extracts of leaves and fruits of B. oxyclada inhibited root growth of barnyardgrass and wild poinsettia seedlings, with a concentration-dependent effect. Decreased shoot growth was observed only in wild poinsettia seedlings. Decreased root growth in wild poinsettia seedlings may be related to decreased elongation in metaxylem cells. Banisteriopsis oxyclada shows phytotoxic properties and it may be regarded as an alternative to control the weeds under study, having natural products as a basis.

  12. Chemical Composition, Antibacterial and Phytotoxic Activities of Peganum harmala Seed Essential Oils from Five Different Localities in Northern Africa

    Directory of Open Access Journals (Sweden)

    Ida Apostolico

    2016-09-01

    Full Text Available Peganum harmala L., also known as Syrian rue or Pègano, is a herbaceous plant belonging to the Zygohpyllaceae family, and is widely used in traditional medicine. The chemical composition of essential oils of P. harmala seeds from five different regions of Northern Africa (Algeria, Egypt, Libya, Morocco and Tunisia was studied by GC and GC-MS analyses. A total of 105 compounds were identified, the main components being oxygenated monoterpenes and oxygenated sesquiterpenes. Eugenol is the main component in all oils. The antimicrobial activity of the essential oils was assayed against some bacterial strains: Staphylococcus aureus (DSM 25693, Bacillus cereus (DSM 4313, Bacillus cereus (DSM4384, Escherichia coli (DMS 857 and Pseudomonas aeruginosa (ATCC 50071. All the oils showed different inhibitory activity. In the twentieth century this is an important result; we need possible new botanical drugs because the problem of resistance to antimicrobial drugs has become apparent. Moreover, the essential oils were evaluated for their possible in vitro phytotoxic activity against germination and initial radicle growth of Raphanus sativus L., Lepidium sativum L., and Ruta graveolens L. The results showed that both germination and radical elongation were sensitive to the oils.

  13. Experience with Remote Job Execution

    International Nuclear Information System (INIS)

    Lynch, Vickie E.; Cobb, John W; Green, Mark L.; Kohl, James Arthur; Miller, Stephen D.; Ren, Shelly; Smith, Bradford C.; Vazhkudai, Sudharshan S.

    2008-01-01

    The Neutron Science Portal at Oak Ridge National Laboratory submits jobs to the TeraGrid for remote job execution. The TeraGrid is a network of high performance computers supported by the US National Science Foundation. There are eleven partner facilities with over a petaflop of peak computing performance and sixty petabytes of long-term storage. Globus is installed on a local machine and used for job submission. The graphical user interface is produced by java coding that reads an XML file. After submission, the status of the job is displayed in a Job Information Service window which queries globus for the status. The output folder produced in the scratch directory of the TeraGrid machine is returned to the portal with globus-url-copy command that uses the gridftp servers on the TeraGrid machines. This folder is copied from the stage-in directory of the community account to the user's results directory where the output can be plotted using the portal's visualization services. The primary problem with remote job execution is diagnosing execution problems. We have daily tests of submitting multiple remote jobs from the portal. When these jobs fail on a computer, it is difficult to diagnose the problem from the globus output. Successes and problems will be presented

  14. [Memory and the executive functions].

    Science.gov (United States)

    Tirapu-Ustárroz, J; Muñoz-Céspedes, J M

    The terms 'executive functioning' or 'executive control' refer to a set of mechanisms involved in the improvement of cognitive processes to guide them towards the resolution of complex problems. Both the frontal lobes, acting as structure, and the executive processes, acting as function, work with memory contents, operating with information placed in the diencephalic structures and in the medial temporal lobe. Generally, we can state that many works find an association between frontal damage and specific memory shortages like working memory deficit, metamemory problems, source amnesia, or difficulties in the prospective memory. This paper is a critical review of the working memory concept and proposes a new term: the attentional operative system that works with memory contents. Concerning the metamemory, the frontal lobes are essential for monitoring processes in general and for 'the feeling of knowing' kind of judgements in particular. Patients suffering prefrontal damage show serious problems to remember the information source. Thus, the information is rightly remembered but the spatiotemporal context where that information was learned has been forgotten. Finally, the prospective memory deals with remembering to make something in a particular moment in the future and performing the plan previously drawn up.

  15. Executive function in fibromyalgia: Comparing subjective and objective measures.

    Science.gov (United States)

    Gelonch, Olga; Garolera, Maite; Valls, Joan; Rosselló, Lluís; Pifarré, Josep

    2016-04-01

    There is evidence to suggest the existence of an executive dysfunction in people diagnosed with fibromyalgia, although there are certain inconsistencies between studies. Here, we aim to compare executive performance between patients with fibromyalgia and a control group by using subjective and objective cognitive tests, analyzing the influence of patient mood on the results obtained, and studying associations between the two measures. 82 patients diagnosed with fibromyalgia and 42 healthy controls, matched by age and years of education, were assessed using the Behavioral Rating Inventory of Executive Function - Adult Version (BRIEF-A) as a subjective measure of executive functioning. A selection of objective cognitive tests were also used to measure a series of executive functions and to identify symptoms of depression and anxiety. Patients with fibromyalgia perceived greater difficulties than the control group on all of the BRIEF-A scales. However, after adjustments were made for depression and anxiety the only differences that remained were those associated with the working memory scale and the Metacognition and Global Executive Composite index. In the case of the objective cognitive tests, a significantly worse overall performance was evidenced for the fibromyalgia patients. However, this also disappeared when adjustments were made for depression and anxiety. After this adjustment, fibromyalgia patients only performed significantly worse for the interference effect in the Stroop Test. Although there were no significant associations between most of the objective cognitive tests and the BRIEF-A scales, depression and anxiety exhibited strong associations with almost all of the BRIEF-A scales and with several of the objective cognitive tests. Patients with fibromyalgia showed executive dysfunction in subjective and objective measures, although most of this impairment was associated with mood disturbances. Exceptions to this general rule were observed in the

  16. Sexual Harassment and Organizational Outcomes Executive Summary

    Science.gov (United States)

    2011-10-01

    quid pro quo type of Sexual harassment and Organizational, 4 sexual harassment (e.g., sexual coercion). This should drive organizational efforts to... Sexual Harassment and Organizational Outcomes Executive Summary Charlie L. Law DEFENSE EQUAL...Executive Summary] No. 99-11 Sexual harassment and Organizational, 2 Executive Summary Issue

  17. 40 CFR 68.155 - Executive summary.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Executive summary. 68.155 Section 68...) CHEMICAL ACCIDENT PREVENTION PROVISIONS Risk Management Plan § 68.155 Executive summary. The owner or operator shall provide in the RMP an executive summary that includes a brief description of the following...

  18. Wildfire: distributed, Grid-enabled workflow construction and execution

    Directory of Open Access Journals (Sweden)

    Issac Praveen

    2005-03-01

    Full Text Available Abstract Background We observe two trends in bioinformatics: (i analyses are increasing in complexity, often requiring several applications to be run as a workflow; and (ii multiple CPU clusters and Grids are available to more scientists. The traditional solution to the problem of running workflows across multiple CPUs required programming, often in a scripting language such as perl. Programming places such solutions beyond the reach of many bioinformatics consumers. Results We present Wildfire, a graphical user interface for constructing and running workflows. Wildfire borrows user interface features from Jemboss and adds a drag-and-drop interface allowing the user to compose EMBOSS (and other programs into workflows. For execution, Wildfire uses GEL, the underlying workflow execution engine, which can exploit available parallelism on multiple CPU machines including Beowulf-class clusters and Grids. Conclusion Wildfire simplifies the tasks of constructing and executing bioinformatics workflows.

  19. 5 CFR 842.211 - Senior Executive Service, Defense Intelligence Senior Executive Service, and Senior Cryptologic...

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Senior Executive Service, Defense Intelligence Senior Executive Service, and Senior Cryptologic Executive Service. 842.211 Section 842.211... EMPLOYEES RETIREMENT SYSTEM-BASIC ANNUITY Eligibility § 842.211 Senior Executive Service, Defense...

  20. Single-instruction multiple-data execution

    CERN Document Server

    Hughes, Christopher J

    2015-01-01

    Having hit power limitations to even more aggressive out-of-order execution in processor cores, many architects in the past decade have turned to single-instruction-multiple-data (SIMD) execution to increase single-threaded performance. SIMD execution, or having a single instruction drive execution of an identical operation on multiple data items, was already well established as a technique to efficiently exploit data parallelism. Furthermore, support for it was already included in many commodity processors. However, in the past decade, SIMD execution has seen a dramatic increase in the set of

  1. 78 FR 55244 - Senior Executive Service Performance Review Board; Membership

    Science.gov (United States)

    2013-09-10

    ... DEFENSE NUCLEAR FACILITIES SAFETY BOARD Senior Executive Service Performance Review Board... the membership of the Defense Nuclear Facilities Safety Board (DNFSB) Senior Executive Service (SES... rating of a senior executive's performance, the executive's response, and the higher level official's...

  2. Potential benefits and phytotoxicity of bulk and nano-chitosan on the growth, morphogenesis, physiology, and micropropagation of Capsicum annuum.

    Science.gov (United States)

    Asgari-Targhi, Ghasem; Iranbakhsh, Alireza; Ardebili, Zahra Oraghi

    2018-06-01

    Concerning environmental issues of metal based-nanomaterials and increasing demand for nano-based products; various strategies have been employed to find eco-friendly natural nano-compounds, among which nano-polymer chitosan is mostly considered. Herein, the various aspects of the way in which bulk or nano-chitosan may modify growth, morphogenesis, micropropagation, and physiology of Capsicum annuum L. were considered. Culture medium was manipulated with different concentrations of bulk chitosan or synthesized chitosan/tripolyphosphate (TPP) nano-particle. The supplementations of culture media led to changes in morphology (especially, the root architecture) and differentiation. Toxic doses of bulk (100 mgL -1 ) or nano-chitosan (5, 10, and 20 mgL -1 ) dramatically provoked cessation of plant growth and development. Plant growth and biomass accumulations were increased along with the suitable levels of bulk or nano-chitosan. Peroxidase and catalase activities in a dose and organ-dependent manners were significantly modified by the supplements. Phenylalanine ammonia lyase was induced by the mentioned supplements. Also, the contents of soluble phenols, proline, and alkaloid were found to be significantly increased by the elicitors, over the control. The nano-chitosan of 1 mgL -1 was found to be the most effective elicitor to trigger organogenesis via micropropagation. The huge differences between triggering and toxic concentrations of the supplements would be due to the physicochemical modifications of nano-polymeric. Furthermore, the results highlight the potential benefits (hormone-like activity) and phytotoxic impacts of nano-chitosan/TPP for in vitro manipulations. This is the first report on both the favorable and adverse effects of nano-chitosan/TPP, representing requirements for further investigation on such formulations for future applications. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  3. Modulation of cadmium-induced phytotoxicity in Cabomba caroliniana by urea involves photosynthetic metabolism and antioxidant status.

    Science.gov (United States)

    Huang, Wenmin; Shao, Hui; Zhou, Sining; Zhou, Qin; Li, Wei; Xing, Wei

    2017-10-01

    Urea is a widespread organic pollutant, which can be a nitrogen source, playing different roles in the growth of submerged macrophytes depending on concentrations, while high cadmium (Cd) concentrations are often toxic to macrophytes. In order to evaluate the combined effect of urea and Cd on a submerged macrophyte, Cabomba caroliniana, the morphological and physiological responses of C. caroliniana in the presence of urea and Cd were studied. The results showed that high concentrations of urea (400mgL -1 ) and Cd (500µmolL -1 ) had negative effects on C. caroliniana. There were strong visible symptoms of toxicity after 4 days of exposure under Cd-alone, 400mgL -1 urea, and Cd+400mgL -1 urea treatments. In addition, 400mgL -1 urea and Cd had adverse effects on C. caroliniana's pigment system. Significant losses in chlorophyll fluorescence and photosynthetic rates, as well as Rubisco activity were also observed under Cd-alone, 400mgL -1 urea, and Cd+400mgL -1 urea treatments. 400mgL -1 urea markedly enhanced Cd toxicity in C. caroliniana, reflected by a sharp decrease in photosynthetic activity and more visible toxicity symptoms. The results of thiobarbituric acid reactive substances (TBARS) pointed to extreme oxidative stress in C. caroliniana induced under Cd or 400mgL -1 urea exposure. Exogenous ascorbate (AsA) protected C. caroliniana from adverse damage in 400mgL -1 urea, which further corroborated the oxidative stress claim under 400mgL -1 urea. However, results also demonstrated that lower urea concentration (10mgL -1 ) alleviated Cd-induced phytotoxicity by stimulating chlorophyll synthesis and photosynthetic activity, as well as activating the activity of catalase (CAT) and glutathione-S-transferase (GST), which may explain the alleviating effect of urea on C. caroliniana under Cd stress. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Phytotoxic cyanamide affects maize (Zea mays) root growth and root tip function: from structure to gene expression.

    Science.gov (United States)

    Soltys, Dorota; Rudzińska-Langwald, Anna; Kurek, Wojciech; Szajko, Katarzyna; Sliwinska, Elwira; Bogatek, Renata; Gniazdowska, Agnieszka

    2014-05-01

    Cyanamide (CA) is a phytotoxic compound produced by four Fabaceae species: hairy vetch, bird vetch, purple vetch and black locust. Its toxicity is due to complex activity that involves the modification of both cellular structures and physiological processes. To date, CA has been investigated mainly in dicot plants. The goal of this study was to investigate the effects of CA in the restriction of the root growth of maize (Zea mays), representing the monocot species. CA (3mM) reduced the number of border cells in the root tips of maize seedlings and degraded their protoplasts. However, CA did not induce any significant changes in the organelle structure of other root cells, apart from increased vacuolization. CA toxicity was also demonstrated by its effect on cell cycle activity, endoreduplication intensity, and modifications of cyclins CycA2, CycD2, and histone HisH3 gene expression. In contrast, the arrangement of microtubules was not altered by CA. Treatment of maize seedlings with CA did not completely arrest mitotic activity, although the frequency of dividing cells was reduced. Furthermore, prolonged CA treatment increased the proportion of endopolyploid cells in the root tip. Cytological malformations were accompanied by an induction of oxidative stress in root cells, which manifested as enhanced accumulation of H2O2. Exposure of maize seedlings to CA resulted in an increased concentration of auxin and stimulated ethylene emission. Taken together, these findings suggested that the inhibition of root growth by CA may be a consequence of stress-induced morphogenic responses. Copyright © 2014. Published by Elsevier GmbH.

  5. Occurrence of chemical contaminants in peri-urban agricultural irrigation waters and assessment of their phytotoxicity and crop productivity.

    Science.gov (United States)

    Margenat, Anna; Matamoros, Víctor; Díez, Sergi; Cañameras, Núria; Comas, Jordi; Bayona, Josep M

    2017-12-01

    Water scarcity and water pollution have increased the pressure on water resources worldwide. This pressure is particularly important in highly populated areas where water demand exceeds the available natural resources. In this regard, water reuse has emerged as an excellent water source alternative for peri-urban agriculture. Nevertheless, it must cope with the occurrence of chemical contaminants, ranging from trace elements (TEs) to organic microcontaminants. In this study, chemical contaminants (i.e., 15 TEs, 34 contaminants of emerging concern (CECs)), bulk parameters, and nutrients from irrigation waters and crop productivity (Lycopersicon esculentum Mill. cv. Bodar and Lactuca sativa L. cv. Batavia) were seasonally surveyed in 4 farm plots in the peri-urban area of the city of Barcelona. A pristine site, where rain-groundwater is used for irrigation, was selected for background concentrations. The average concentration levels of TEs and CECs in the irrigation water impacted by treated wastewater (TWW) were 3 (35±75μgL -1 ) and 13 (553±1050ngL -1 ) times higher than at the pristine site respectively. Principal component analysis was used to classify the irrigation waters by chemical composition. To assess the impact of the occurrence of these contaminants on agriculture, a seed germination assay (Lactuca sativa L) and real field-scale study of crop productivity (i.e., lettuce and tomato) were used. Although irrigation waters from the peri-urban area exhibited a higher frequency of detection and concentration of the assessed chemical contaminants than those of the pristine site (P1), no significant differences were found in seed phytotoxicity or crop productivity. In fact, the crops impacted by TWW showed higher productivity than the other farm plots studied, which was associated with the higher nutrient availability for plants. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Phenolics from Ageratina adenophora roots and their phytotoxic effects on Arabidopsis thaliana seed germination and seedling growth.

    Science.gov (United States)

    Zhou, Zhong-Yu; Liu, Wan-Xue; Pei, Gang; Ren, Hui; Wang, Jing; Xu, Qiao-Lin; Xie, Hai-Hui; Wan, Fang-Hao; Tan, Jian-Wen

    2013-12-04

    A bioassay-directed phytochemical study was conducted to investigate potential allelochemicals in the roots of the invasive plant Ageratina adenophora. Eleven phenolic compounds, including seven new ones, 7-hydroxy-8,9-dehydrothymol 9-O-trans-ferulate (1), 7-hydroxythymol 9-O-trans-ferulate (2), 7,8-dihydroxythymol 9-O-trans-ferulate (3), 7,8-dihydroxythymol 9-O-cis-ferulate (4), methyl (7R)-3-deoxy-4,5-epoxy-D-manno-2-octulosonate 8-O-trans-p-coumarate (5), methyl (7R)-3-deoxy-4,5-epoxy-D-manno-2-octulosonate 8-O-cis-p-coumarate (6), and 3-(2-hydroxyphenyl)propyl methyl malonate (7), were isolated from a bioactive subfraction of the ethanol extract of the roots of A. adenophora. The new structures were established on the basis of detailed spectroscopic analysis. The potential phytotoxic effects of these compounds on the germination of Arabidopsis thaliana seeds were tested by a filter paper assay. Compound 7 and known compounds 3-(2-hydroxyphenyl)-1-propanol (8) and o-coumaric acid (9) remarkably showed inhibition activity against Arabidopsis seed germination at a concentration of 1.0 mM. Compounds 1, 2, 5, 6, and 10 showed slight inhibitory activity at the test concentration after treatment for 3 days, while the other compounds showed no obvious inhibitory effects. Moreover, 7-9 were further found to show obvious inhibitory activity on retarding the seedling growth of Ar. thaliana cultured in soil medium.

  7. Assessment of the Phytotoxicity of Metal Oxide Nanoparticles on Two Crop Plants, Maize (Zea mays L.) and Rice (Oryza sativa L.).

    Science.gov (United States)

    Yang, Zhongzhou; Chen, Jing; Dou, Runzhi; Gao, Xiang; Mao, Chuanbin; Wang, Li

    2015-11-30

    In this study, the phytotoxicity of seven metal oxide nanoparticles(NPs)-titanium dioxide (nTiO₂), silicon dioxide (nSiO₂), cerium dioxide (nCeO₂), magnetite (nFe₃O₄), aluminum oxide (nAl₂O₃), zinc oxide (nZnO) and copper oxide (nCuO)-was assessed on two agriculturally significant crop plants (maize and rice). The results showed that seed germination was not affected by any of the seven metal oxide NPs. However, at the concentration of 2000 mg·L(-1), the root elongation was significantly inhibited by nCuO (95.73% for maize and 97.28% for rice), nZnO (50.45% for maize and 66.75% for rice). On the contrary, minor phytotoxicity of nAl₂O₃ was only observed in maize, and no obvious toxic effects were found in the other four metal oxide NPs. By further study we found that the phytotoxic effects of nZnO, nAl₂O₃ and nCuO (25 to 2000 mg·L(-)¹) were concentration dependent, and were not caused by the corresponding Cu(2+), Zn(2+) and Al(3+) ions (0.11 mg·L(-)¹, 1.27 mg·L(-)¹ and 0.74 mg·L(-)¹, respectively). Furthermore, ZnO NPs (<50 nm) showed greater toxicity than ZnO microparticles(MPs)(<5 μm) to root elongation of both maize and rice. Overall, this study provided valuable information for the application of engineered NPs in agriculture and the assessment of the potential environmental risks.

  8. Cochliotoxin, a Dihydropyranopyran-4,5-dione, and Its Analogues Produced by Cochliobolus australiensis Display Phytotoxic Activity against Buffelgrass (Cenchrus ciliaris).

    Science.gov (United States)

    Masi, Marco; Meyer, Susan; Clement, Suzette; Cimmino, Alessio; Cristofaro, Massimo; Evidente, Antonio

    2017-05-26

    Buffelgrass (Pennisetum ciliare or Cenchrus ciliaris) is a perennial grass that has become highly invasive in the Sonoran Desert of southern Arizona. In the search for novel control strategies against this weed, strains of the foliar fungal pathogen Cochliobolus australiensis from buffelgrass have been screened for their ability to produce phytotoxic metabolites that could potentially be used as natural herbicides in an integrated pest management strategy. A new phytotoxin, named cochliotoxin, was isolated from liquid culture of this fungus together with radicinin, radicinol, and their 3-epimers. Cochliotoxin was characterized, essentially by spectroscopic methods, as 3-hydroxy-2-methyl-7-(3-methyloxiranyl)-2,3-dihydropyrano[4,3-b]pyran-4,5-dione. Its relative stereochemistry was assigned by 1 H NMR techniques, while the absolute configuration (2S,3S) was determined applying the advanced Mosher's method by esterification of its hydroxy group at C-3. When bioassayed in a buffelgrass coleoptile elongation test and by leaf puncture bioassay against the host weed and two nontarget grasses, cochliotoxin showed strong phytotoxicity. In the same tests, radicinin and 3-epi-radicinin also showed phytotoxic activity, while radicinol and 3-epi-radicinol were largely inactive. All five compounds were more active in leaf puncture bioassays on buffelgrass than on the nontarget grass tanglehead (Heteropogon contortus), while the nontarget grass Arizona cottontop (Digitaria californica) was more sensitive to radicinin and 3-epi-radicinin. Cochliotoxin at low concentration was significantly more active on buffelgrass than on either native grass, but the difference was small.

  9. Career patterns of healthcare executives.

    Science.gov (United States)

    Fahey, D F; Myrtle, R C

    2001-02-01

    This research examines the job and career changes of healthcare executives and managers working in different segments of the healthcare industry in the western United States. The results suggest that the job and career patterns in the healthcare delivery sector are undergoing significant transformation. One third of the respondents reports that at least one of their last four job changes was involuntary or unplanned. One half of those attempted to make a career change. This study identifies four different executive and management career patterns. The most common was one of multiple career changes. The second pattern was that of a single career change, followed by a 'traditional' career in which one did not seek a career change. The final pattern was characterized as a movement back and forth between two different segments of the healthcare industry. Age, gender, marital status and education were not associated with any specific career pattern. The need to achieve results early in the respondent's career had a strong influence on career patterns. This study confirms the fluidity of career movement and the changing permeability between the various segments of the healthcare industry. It also suggests that career success increasingly will require broad management experience in those different segments.

  10. Balancing Automatic-Controlled Behaviors and Emotional-Salience States: A Dynamic Executive Functioning Hypothesis.

    Science.gov (United States)

    Kluwe-Schiavon, Bruno; Viola, Thiago W; Sanvicente-Vieira, Breno; Malloy-Diniz, Leandro F; Grassi-Oliveira, Rodrigo

    2016-01-01

    Recently, there has been growing interest in understanding how executive functions are conceptualized in psychopathology. Since several models have been proposed, the major issue lies within the definition of executive functioning itself. Theoretical discussions have emerged, narrowing the boundaries between "hot" and "cold" executive functions or between self-regulation and cognitive control. Nevertheless, the definition of executive functions is far from a consensual proposition and it has been suggested that these models might be outdated. Current efforts indicate that human behavior and cognition are by-products of many brain systems operating and interacting at different levels, and therefore, it is very simplistic to assume a dualistic perspective of information processing. Based upon an adaptive perspective, we discuss how executive functions could emerge from the ability to solve immediate problems and to generalize successful strategies, as well as from the ability to synthesize and to classify environmental information in order to predict context and future. We present an executive functioning perspective that emerges from the dynamic balance between automatic-controlled behaviors and an emotional-salience state. According to our perspective, the adaptive role of executive functioning is to automatize efficient solutions simultaneously with cognitive demand, enabling individuals to engage such processes with increasingly complex problems. Understanding executive functioning as a mediator of stress and cognitive engagement not only fosters discussions concerning individual differences, but also offers an important paradigm to understand executive functioning as a continuum process rather than a categorical and multicomponent structure.

  11. Executive functions and theory of mind as predictors of social adjustment in childhood traumatic brain injury.

    Science.gov (United States)

    Robinson, Kristen E; Fountain-Zaragoza, Stephanie; Dennis, Maureen; Taylor, H Gerry; Bigler, Erin D; Rubin, Kenneth; Vannatta, Kathryn; Gerhardt, Cynthia A; Stancin, Terry; Yeates, Keith Owen

    2014-11-15

    This study examined whether executive function and theory of mind mediate the effects of pediatric traumatic brain injury (TBI) on social adjustment, relative to children with orthopedic injury (OI). Participants included 19 children with severe TBI, 41 children with complicated mild/moderate TBI, and 57 children with OI. They completed measures of executive function, as well as cognitive, affective, and conative theory of mind. Parents provided ratings of children's social adjustment. Children with severe TBI performed more poorly than children with OI on executive function and theory of mind tasks and were rated by parents as having more behavioral symptoms and worse communication and social skills. Executive function and theory of mind were positively correlated with social skills and communication skills, and negatively correlated with behavioral symptoms. In multiple mediator models, theory of mind and executive function were not significant direct predictors of any measure of social adjustment, but mediated the association between injury and adjustment for children with severe TBI. Theory of mind was a significant independent mediator when predicting social skills, but executive function was not. TBI in children, particularly severe injury, is associated with poor social adjustment. The impact of TBI on children's social adjustment is likely mediated by its effects on executive function and theory of mind.

  12. synthesis, antimicrobial and phytotoxic activity of amide derivatives of L-(+)-2,3-diacetoxy-4-methoxy-4-oxo-butanoic acid

    International Nuclear Information System (INIS)

    Malik, M.; Khan, S.W.; Zaidi, J.H.; Khan, K.M.; Hussain, S.

    2014-01-01

    A short, versatile, an efficient asymmetric synthesis of substituted aromatic amides is described. L-Tartaric acid conveniently converted into diacetyl-L-tartaric anhydride. Diacetyl-L-tartaric anhydride was then transformed into half ester which was then reacted with substituted anilines to yield respective chiral amides 3-8. These chiral amides were characterized by spectroscopic techniques i.e. 1H-NMR, 13C-NMR, IR and mass spectrometry. Amides 3-8 were tested for their antimicrobial as well as phytotoxic activities. (author)

  13. Relations Between Executive Functions and Different Symptomatic Dimensions in Obsessive Compulsive Disorder

    OpenAIRE

    Pedron, Ana Cristina; Ferrão, Ygor Arzeno; Gurgel, Léia Gonçalves; Reppold, Caroline Tozzi

    2015-01-01

    There is no consensus in the literature as to neuropsychological functioning, the severity of obsessive-compulsive symptoms (OCS) and the definitions of the OCS dimensions. We conducted a cross-sectional study investigating the relationship between executive function and OCS severity in the various dimensions, according to the Dimensional Yale-Brown Obsessive-Compulsive Scale criteria. We evaluated 28 patients with OCS, using eight neuropsychological instruments to evaluate executive function...

  14. An Investigation of Executive Functioning in Pediatric Anxiety.

    Science.gov (United States)

    Murphy, Yolanda E; Luke, Anna; Brennan, Elle; Francazio, Sarah; Christopher, Isabella; Flessner, Christopher A

    2018-01-01

    Although science's understanding (e.g., etiology, maintaining factors, etc.) of pediatric anxiety and related problems has grown substantially over recent years, several aspects to anxiety in youths remain elusive, particularly with relation to executive functioning. To this end, the current study sought to examine several facets to executive functioning (i.e., cognitive flexibility, inhibition, planning, working memory) within a transdiagnostic sample of youths exhibiting varying degrees of anxiety symptoms. One hundred six youths completed a comprehensive battery, including several self-report measures (e.g., Multidimensional Anxiety Scale for Children [MASC] or MASC-2) and an automated neurocognitive battery of several executive functioning tasks (Intradimensional/Extradimensional [IDED], Stop Signal [SST], Spatial Span [SSP], Stockings of Cambridge [SOC] tasks). Regression analyses indicated that youths exhibiting marked anxiety symptoms demonstrated increased planning time and probability of inhibition compared with youths with minimal or no anxiety symptoms. Youths with marked anxiety symptoms similarly demonstrated better cognitive flexibility (i.e., set shifting) compared with youths with minimal anxiety. In addition, analyses indicated a trend such that youths exhibiting marked anxiety symptoms demonstrated poorer working memory compared with youths with no anxiety symptoms. Group classification did not predict remaining outcomes. Limitations and future areas of research are discussed.

  15. Executive function, episodic memory, and Medicare expenditures.

    Science.gov (United States)

    Bender, Alex C; Austin, Andrea M; Grodstein, Francine; Bynum, Julie P W

    2017-07-01

    We examined the relationship between health care expenditures and cognition, focusing on differences across cognitive systems defined by global cognition, executive function, or episodic memory. We used linear regression models to compare annual health expenditures by cognitive status in 8125 Nurses' Health Study participants who completed a cognitive battery and were enrolled in Medicare parts A and B. Adjusting for demographics and comorbidity, executive impairment was associated with higher total annual expenditures of $1488 per person (P episodic memory impairment was found. Expenditures exhibited a linear relationship with executive function, but not episodic memory ($584 higher for every 1 standard deviation decrement in executive function; P < .01). Impairment in executive function is specifically and linearly associated with higher health care expenditures. Focusing on management strategies that address early losses in executive function may be effective in reducing costly services. Copyright © 2017 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

  16. Executable Architecture Research at Old Dominion University

    Science.gov (United States)

    Tolk, Andreas; Shuman, Edwin A.; Garcia, Johnny J.

    2011-01-01

    Executable Architectures allow the evaluation of system architectures not only regarding their static, but also their dynamic behavior. However, the systems engineering community do not agree on a common formal specification of executable architectures. To close this gap and identify necessary elements of an executable architecture, a modeling language, and a modeling formalism is topic of ongoing PhD research. In addition, systems are generally defined and applied in an operational context to provide capabilities and enable missions. To maximize the benefits of executable architectures, a second PhD effort introduces the idea of creating an executable context in addition to the executable architecture. The results move the validation of architectures from the current information domain into the knowledge domain and improve the reliability of such validation efforts. The paper presents research and results of both doctoral research efforts and puts them into a common context of state-of-the-art of systems engineering methods supporting more agility.

  17. Culture, executive function, and social understanding.

    Science.gov (United States)

    Lewis, Charlie; Koyasu, Masuo; Oh, Seungmi; Ogawa, Ayako; Short, Benjamin; Huang, Zhao

    2009-01-01

    Much of the evidence from the West has shown links between children's developing self-control (executive function), their social experiences, and their social understanding (Carpendale & Lewis, 2006, chapters 5 and 6), across a range of cultures including China. This chapter describes four studies conducted in three Oriental cultures, suggesting that the relationships among social interaction, executive function, and social understanding are different in these cultures, implying that social and executive skills are underpinned by key cultural processes.

  18. Spirituality and the physician executive.

    Science.gov (United States)

    Kaiser, L R

    2000-01-01

    The "s" word can now be spoken without flinching in health care organizations. Spirituality is becoming a common topic in management conferences around the world. Many U.S. corporations are recognizing the role of spirituality in creating a new humanistic capitalism that manages beyond the bottom line. Spirituality refers to a broad set of principles that transcend all religions. It is the relationship between yourself and something larger, such as the good of your patient or the welfare of the community. Spirituality means being in right relationship to all that is and understanding the mutual interdependence of all living beings. Physician executives should be primary proponents of spirituality in their organizations by: Modeling the power of spirituality in their own lives; integrating spiritual methodologies into clinical practice; fostering an integrative approach to patient care; encouraging the organization to tithe its profits for unmet community health needs; supporting collaborative efforts to improve the health of the community; and creating healing environments.

  19. CSP for Executable Scientific Workflows

    DEFF Research Database (Denmark)

    Friborg, Rune Møllegaard

    and can usually benefit performance-wise from both multiprocessing, cluster and grid environments. PyCSP is an implementation of Communicating Sequential Processes (CSP) for the Python programming language and takes advantage of CSP's formal and verifiable approach to controlling concurrency...... on multi-processing and cluster computing using PyCSP. Additionally, McStas is demonstrated to utilise grid computing resources using PyCSP. Finally, this thesis presents a new dynamic channel model, which has not yet been implemented for PyCSP. The dynamic channel is able to change the internal...... synchronisation mechanisms on-the-fly, depending on the location and number of channel-ends connected. Thus it may start out as a simple local pipe and evolve into a distributed channel spanning multiple nodes. This channel is a necessary next step for PyCSP to allow for complete freedom in executing CSP...

  20. Advanced Fuels Campaign Execution Plan

    Energy Technology Data Exchange (ETDEWEB)

    Kemal Pasamehmetoglu

    2010-10-01

    The purpose of the Advanced Fuels Campaign (AFC) Execution Plan is to communicate the structure and management of research, development, and demonstration (RD&D) activities within the Fuel Cycle Research and Development (FCRD) program. Included in this document is an overview of the FCRD program, a description of the difference between revolutionary and evolutionary approaches to nuclear fuel development, the meaning of science-based development of nuclear fuels, and the “Grand Challenge” for the AFC that would, if achieved, provide a transformational technology to the nuclear industry in the form of a high performance, high reliability nuclear fuel system. The activities that will be conducted by the AFC to achieve success towards this grand challenge are described and the goals and milestones over the next 20 to 40 year period of research and development are established.

  1. Advanced Fuels Campaign Execution Plan

    Energy Technology Data Exchange (ETDEWEB)

    Kemal Pasamehmetoglu

    2011-09-01

    The purpose of the Advanced Fuels Campaign (AFC) Execution Plan is to communicate the structure and management of research, development, and demonstration (RD&D) activities within the Fuel Cycle Research and Development (FCRD) program. Included in this document is an overview of the FCRD program, a description of the difference between revolutionary and evolutionary approaches to nuclear fuel development, the meaning of science-based development of nuclear fuels, and the 'Grand Challenge' for the AFC that would, if achieved, provide a transformational technology to the nuclear industry in the form of a high performance, high reliability nuclear fuel system. The activities that will be conducted by the AFC to achieve success towards this grand challenge are described and the goals and milestones over the next 20 to 40 year period of research and development are established.

  2. EMI Execution Service (EMI-ES) Specification

    CERN Document Server

    Schuller, B

    2010-01-01

    This document provides the interface specification, including related data models such as state model, activity description, resource and activity information, of an execution service, matching the needs of the EMI production middleware stack composed of ARC, gLite and UNICORE components. This service therefore is referred to as the EMI Execution Service (or “ES” for short). This document is a continuation of the work previously know as the GENEVA, then AGU (“ARC, gLite UNICORE”), then PGI execution service. As a starting point, the v0.42 of the “PGI Execution Service Specification” (doc15839) was used.

  3. A simple hypothesis of executive function

    Directory of Open Access Journals (Sweden)

    Bruno eKopp

    2012-06-01

    Full Text Available Executive function is traditionally conceptualized as a set of abilities required to guide behavior toward goals. Here, an integrated theoretical framework for executive function is developed which has its roots in the notion of hierarchical mental models. Further following Duncan (2010a,b, executive function is construed as a hierarchical recursive system of test-operation-test-exit units (Miller, Galanter, and Pribram, 1960. Importantly, it is shown that this framework can be used to model the main regional prefrontal syndromes, which are characterized by apathetic, disinhibited and dysexecutive cognition and behavior, respectively. Implications of these considerations for the neuropsychological assessment of executive function are discussed.

  4. Executive Orders-William J. Clinton

    Data.gov (United States)

    National Archives and Records Administration — Executive orders are official documents, numbered consecutively, through which the President of the United States manages the operations of the Federal Government....

  5. +Gz load and executive functions.

    Science.gov (United States)

    Biernacki, Marcin P; Tarnowski, Adam; Lengsfeld, Kamila; Lewkowicz, Rafał; Kowalczuk, Krzysztof; Dereń, Miroslaw

    2013-05-01

    Pilots are constantly exposed to a number of environmental factors, which include +Gz load. Physiological changes evoked by +Gz stimuli have already been well investigated in aviation medicine. However, the influence of +Gz stimulation on executive functions in pilots has not yet been thoroughly explored. There were 20 pilot cadets between the ages of 19 and 22 yr who volunteered to participate in the experiment. The subjects were divided into two groups: the G-load group, which was exposed to accelerations in the centrifuge, and the control group, which did not undergo this stimulation. Executive functions were assessed by means of the Schulte tables and the Rey-Osterrieth complex figure test. +Gz load exposure significantly improved attention switching. This relationship was valid for performance speed (M = 268.09 s in the pretest in the G-load group; M = 228.09 s in the posttest in the G-load group) and for the cumulative time of mistakes (M = 26.73 s in the pretest in the G-load group; M = 12 s in the posttest in the G-load group), whereas reproduction of visuospatial stimuli from memory deteriorated significantly under the influence of +Gz stimulation (M = 17.18 points in the posttest in the G-load group; M = 28.18 points in the posttest in the control group). These results suggest that the impact of +Gz load is not homogenous and unidirectional, since it improves attention switching but visuospatial working memory decreases under its influence. These aspects are particularly important for understanding the mechanisms responsible for maintaining situational awareness during the flight.

  6. Ormen Lange subsea development strategy and execution

    Energy Technology Data Exchange (ETDEWEB)

    Hogmoen, K. [Norsk Hydro, Oslo (Norway)

    2007-07-01

    Ormen Lange is the largest natural gas field in development on the Norwegian continental shelf. This paper discussed Norsk Hydro's Ormen Lange development strategy and execution. Several illustrations of the Ormen Lange project were presented, including the field layout and the main challenges of working in deep water. Other challenges involve environmental conditions; long distance control; and hydrate prevention. Several components of the project were presented, including the xmas tree handling system; choke module; control system; large bore tie-in system; in-line tee system; and free spans in pipeline design. Other topics that were presented and illustrated included the feasibility of pipeline design; design optimization with installation contractors; design optimization between intervention methods; positioning; dredging with spiders; excavation with jetprops; ploughing; rock installation; and trenching. The installation of thirty inch pipelines and umbilical lines in shallow and deep water were also discussed and illustrated. The presentation concluded with a discussion of lessons learned subsea. These included early definition of operational requirements; close monitoring of interface work between contractors; professional change management; and thorough testing onshore prior to installation. Securing vessel capacity and timely start-up were among the lessons learned for marine operations. figs.

  7. Phytotoxic substances in soils of polluted beech forest stands; Phytotoxische Stoffe in Boeden immissionsbelasteter Buchenwaelder

    Energy Technology Data Exchange (ETDEWEB)

    Glavac, V.; Parlar, H.; Michalas, F.; Droefke, P.

    1992-12-31

    Extensive germination experiments and growth experiments were carried out under controlled laboratory conditions with garden cress (Lepidium sativum ssp. sativum). The experiments show that the germination capacity ability of the plants in soil areas under old beech trees which are influenced by the trunk runoff water is impaired considerably. The investigations with nutrient solutions permit the following conclusion: The absence or occurrence of germinating plant species in the tree foot area is not influenced by the minerals alone but above all by organic compounds. In this investigation, the growth-inhibiting effect of several phenolic acids occurring in beech forests is recognized. (orig.) [Deutsch] Die umfangreichen Keim- und Wachstumsversuche mit der Gartenkresse (Lepidium sativum ssp.sativum), die unter kontrollierten Laborbedingungen durchgefuehrt wurden, zeigen, dass die Keimfaehigkeit der Pflanzen in den vom Stammablaufwasser beeinflussten Bodenbereichen der Altbuchen deutlich gehemmt wird. Die Untersuchungen mit Naehrloesungen lassen die Schlussfolgerung zu, dass nicht die Mineralstoffe allein, sondern vor allem organische Verbindungen das Fehlen oder Vorkommen aufkeimender Pflanzenarten im Baumflussbereich weitgehend bedingen. In dieser Untersuchung wird die wachstumshemmende Wirkung von mehreren im Oekosystem Buchenwald vorkommenden phenolischen Saeuren nachgewiesen. (orig.)

  8. Potential of the TCE-degrading endophyte Pseudomonas putida W619-TCE to improve plant growth and reduce TCE phytotoxicity and evapotranspiration in poplar cuttings

    International Nuclear Information System (INIS)

    Weyens, Nele; Truyens, Sascha; Dupae, Joke; Newman, Lee; Taghavi, Safiyh; Lelie, Daniel van der; Carleer, Robert; Vangronsveld, Jaco

    2010-01-01

    The TCE-degrading poplar endophyte Pseudomonas putida W619-TCE was inoculated in poplar cuttings, exposed to 0, 200 and 400 mg l -1 TCE, that were grown in two different experimental setups. During a short-term experiment, plants were grown hydroponically in half strength Hoagland nutrient solution and exposed to TCE for 3 days. Inoculation with P. putida W619-TCE promoted plant growth, reduced TCE phytotoxicity and reduced the amount of TCE present in the leaves. During a mid-term experiment, plants were grown in potting soil and exposed to TCE for 3 weeks. Here, inoculation with P. putida W619-TCE had a less pronounced positive effect on plant growth and TCE phytotoxicity, but resulted in strongly reduced amounts of TCE in leaves and roots of plants exposed to 400 mg l -1 TCE, accompanied by a lowered evapotranspiration of TCE. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), which are known intermediates of TCE degradation, were not detected. - The endophyte P. putida W619-TCE degrades TCE during its transport through the xylem, leading to reduced TCE concentrations in poplar, and decreased TCE evapotranspiration.

  9. Potential of the TCE-degrading endophyte Pseudomonas putida W619-TCE to improve plant growth and reduce TCE phytotoxicity and evapotranspiration in poplar cuttings.

    Science.gov (United States)

    Weyens, Nele; Truyens, Sascha; Dupae, Joke; Newman, Lee; Taghavi, Safiyh; van der Lelie, Daniel; Carleer, Robert; Vangronsveld, Jaco

    2010-09-01

    The TCE-degrading poplar endophyte Pseudomonas putida W619-TCE was inoculated in poplar cuttings, exposed to 0, 200 and 400 mg l(-1) TCE, that were grown in two different experimental setups. During a short-term experiment, plants were grown hydroponically in half strength Hoagland nutrient solution and exposed to TCE for 3 days. Inoculation with P. putida W619-TCE promoted plant growth, reduced TCE phytotoxicity and reduced the amount of TCE present in the leaves. During a mid-term experiment, plants were grown in potting soil and exposed to TCE for 3 weeks. Here, inoculation with P. putida W619-TCE had a less pronounced positive effect on plant growth and TCE phytotoxicity, but resulted in strongly reduced amounts of TCE in leaves and roots of plants exposed to 400 mg l(-1) TCE, accompanied by a lowered evapotranspiration of TCE. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), which are known intermediates of TCE degradation, were not detected. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  10. The fungicidal and phytotoxic properties of benomyl and PPM in supplemented agar media supporting transgenic arabidopsis plants for a Space Shuttle flight experiment

    Science.gov (United States)

    Paul, A. L.; Semer, C.; Kucharek, T.; Ferl, R. J.

    2001-01-01

    Fungal contamination is a significant problem in the use of sucrose-enriched agar-based media for plant culture, especially in closed habitats such as the Space Shuttle. While a variety of fungicides are commercially available, not all are equal in their effectiveness in inhibiting fungal contamination. In addition, fungicide effectiveness must be weighed against its phytotoxicity and in this case, its influence on transgene expression. In a series of experiments designed to optimize media composition for a recent shuttle mission, the fungicide benomyl and the biocide "Plant Preservative Mixture" (PPM) were evaluated for effectiveness in controlling three common fungal contaminants, as well as their impact on the growth and development of arabidopsis seedlings. Benomyl proved to be an effective inhibitor of all three contaminants in concentrations as low as 2 ppm (parts per million) within the agar medium, and no evidence of phytotoxicity was observed until concentrations exceeded 20 ppm. The biocide mix PPM was effective as a fungicide only at concentrations that had deleterious effects on arabidopsis seedlings. As a result of these findings, a concentration of 3 ppm benomyl was used in the media for experiment PGIM-01 which flew on shuttle Columbia mission STS-93 in July 1999.

  11. Insecticidal, repellent, antimicrobial activity and phytotoxicity of essential oils: With special reference to limonene and its suitability for control of insect pests

    Directory of Open Access Journals (Sweden)

    M.A. IBRAHIM

    2008-12-01

    Full Text Available The interest in the use of monoterpenes for insect pest and pathogen control originates from the need for pesticide products with less negative environmental and health impacts than highly effective synthetic pesticides. The expanding literature on the possibility of the use of these monoterpenes is reviewed and focused on the effects of limonene on various bioorganisms. Limonene is used as insecticide to control ectoparasites of pet animals, but it has activity against many insects, mites, and microorganisms. Possible attractive effects of limonene to natural enemies of pests may offer novel applications to use natural compounds for manipulation of beneficial animals in organic agriculture. However, in few cases limonene-treated plants have become attractive to plant damaging insects and phytotoxic effects on cultivated plants have been observed. As a plant-based natural product limonene and other monoterpenes might have use in pest and weed control in organic agriculture after phytotoxicity on crop plants and, effects on non-target soil animals and natural enemies of pest have been investigated

  12. Potential of the TCE-degrading endophyte Pseudomonas putida W619-TCE to improve plant growth and reduce TCE phytotoxicity and evapotranspiration in poplar cuttings

    Energy Technology Data Exchange (ETDEWEB)

    Weyens, N.; van der Lelie, D.; Truyens, S.; Dupae, J.; Newman, L.; Taghavi, S.; Carleer, R.; Vangronsveld, J.

    2010-09-01

    The TCE-degrading poplar endophyte Pseudomonas putida W619-TCE was inoculated in poplar cuttings, exposed to 0, 200 and 400 mg l{sup -1} TCE, that were grown in two different experimental setups. During a short-term experiment, plants were grown hydroponically in half strength Hoagland nutrient solution and exposed to TCE for 3 days. Inoculation with P. putida W619-TCE promoted plant growth, reduced TCE phytotoxicity and reduced the amount of TCE present in the leaves. During a mid-term experiment, plants were grown in potting soil and exposed to TCE for 3 weeks. Here, inoculation with P. putida W619-TCE had a less pronounced positive effect on plant growth and TCE phytotoxicity, but resulted in strongly reduced amounts of TCE in leaves and roots of plants exposed to 400 mg l{sup -1} TCE, accompanied by a lowered evapotranspiration of TCE. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), which are known intermediates of TCE degradation, were not detected. The endophyte P. putida W619-TCE degrades TCE during its transport through the xylem, leading to reduced TCE concentrations in poplar, and decreased TCE evapotranspiration.

  13. Using bamboo biochar with compost for the stabilization and phytotoxicity reduction of heavy metals in mine-contaminated soils of China.

    Science.gov (United States)

    Ali, Amjad; Guo, Di; Zhang, Yue; Sun, Xining; Jiang, Shuncheng; Guo, Zhanyu; Huang, Hui; Liang, Wen; Li, Ronghua; Zhang, Zengqiang

    2017-06-02

    Anthropogenic activities have transformed the global geochemical cycling of heavy metals (HMs). Many physical, chemical and biological methods are used to reduce the toxicity of HMs to humans, plants and environment. This study aimed to investigate the immobilization and phytotoxicity reduction of HMs after application of bamboo biochar (BB) in mine-polluted soil in Feng county (FC) and Tongguan (TG). The results showed that BB application to contaminated soil immobilized HMs (Zn, Pb, Cd and Cu). The soil pH and EC increased and the bioavailability of HMs decreased in FC and TG, whereas Pb and Cu increased in TG soil. The addition of BB reduced HMs uptake in the shoot/root of Brassica juncea. Physiological responses showed that BB application improved the shoot/root growth, dry biomass, and enhanced the chlorophyll (a and b) and carotenoid concentrations in Brassica. The incorporation of BB improved the soil health and accelerated enzymatic activities (β-glucosidase, alkaline phosphatase and urease) in HMs polluted soils. Antioxidant activities (POD, PPO, CAT and SOD) were also used as biomarkers to determine the negative effects of HMs on the growth of Brassica. Overall, the immobilization potential and phytotoxicity reduction of HMs were confirmed by BCF, TF and MEA for both soils.

  14. Phytotoxic potential of Senna occidentalis and Senna obtusifolia = Potencial fitotóxico de Senna occidentalis e Senna obtusifolia

    Directory of Open Access Journals (Sweden)

    Marize Terezinha Lopes Pereira Peres

    2010-07-01

    Full Text Available This work aimed to investigate the phytotoxic potential of the aerial and underground parts of Senna occidentalis and S. obtusifolia on the germination and initial growth of lettuce and onion. Four concentrations were used of each ethanol extract (0, 250, 500 and 1000 mg L-1, with four replications of 50 seeds. From the investigated species, the aerial part of S. occidentalis interfered in onion germination and the aerial part of S. obtusifolia interfered in the germinations of lettuce and onion. The ethanol extract from the aerial and underground parts of the studied species inhibited the root growth of lettuce and onion. The hypocotyl/coleoptile growth in lettuce and onion was inhibited by the extract of S. obtusifolia aerial part and the underground part of S. occidentalis and S. obtusifolia. The results obtained make it possible to infer that the studied species contain substances that influence the germination and growth of the target seedlings.O objetivo do presente trabalho foi investigar o potencial fitotóxico das partes aérea e subterrânea de Senna occidentalis e S. obtusifolia sobre a germinação e o crescimento inicial de alface e cebola.Utilizaram-se quatro concentrações de cada extrato etanólico (0, 250, 500 e 1000 mg L-1, com quatro repetições de 50 sementes. Das espécies investigadas, a parte aérea de S. occidentalis interferiu na germinação de cebola e a parte aérea de S. obtusifolia, na germinação de alface e cebola. O extrato etanólico da parte aérea e subterrânea, das espécies em estudo, inibiu o crescimento da raiz de alface e de cebola. O crescimento do hipocótilo/coleóptilo de alface e cebola foi inibido pelo extrato da parte aérea de S. obtusifolia e da subterrânea de S. occidentalis e S. obtusifolia. Os resultados obtidos permitem inferir que as espécies em estudo contêm substâncias que influenciam a germinação e o crescimento das plântulas-alvo.

  15. Phytotoxic Effects of Nepeta meyeri Benth. Extracts and Essential Oil on Seed Germinations and Seedling Growths of Four Weed Species

    Directory of Open Access Journals (Sweden)

    Saban Kordali

    2015-05-01

    Full Text Available Essential oil isolated from the aerial parts of Nepeta meyeri Benth. by hydrodistilation was analysed by GC and GC-MS methods. A total 18 components were identified in the oil representing 100.0% of the oil. Main components were 4aα,7α,7aβ-nepetalactone (80.3%, 4aα,7α,7aα–nepetalactone (10.3%, trans-pulegol (3.1%, 1, 8-cineole (3.0% and β-bourbonene (2.0%. In addition, n-hexane extract of N. meyeri was analysed by using GC and GC-MS methods and 18 components were identified. Likewise, nepetalactones, 4aα,7α,7aβ-nepetalactone (83.7%, 4aα,7α,7aα–nepetalactone (3.6%, 1, 8-cineole (1.9% and α-terpinene (1.5% were the predominat compounds in the hexane extract. Three concentrations (0.5, 1.0 and 2.0 mg/mL of the essential oil and n-hexane, chloroform, acetone and methanol extracts isolated from the aerial partsand roots were tested for the herbicidal effects on the germination of the seeds of four weed species including Amaranthus retroflexus L., Chenopodium album L., Cirsium arvense L. and Sinapsis arvensis L. The essential oil of N. meyeri completely inhibited the germination of all weed seeds whereas the extracts showed various inhibition effects on the germination of the weed species. Herbicidal effect was increased with the increasing application concentrations of the extracts. In general, the acetone extract was found to be more effective as compared to the other extracts. All extracts also exhibited various inhibition effects on the seedling growths of the weed species. All extracts also tested for their phytotoxic effects on the weeds at greenhouse condition and the results showed that the oil and extracts caused mortality with 22.00-66.00% 48h after the treatments. These findings suggest that the essential oil and the extracts of N. meyeri have potentials for use as herbicides against those weed species.

  16. Parenting style is related to executive dysfunction after brain injury in children.

    Science.gov (United States)

    Potter, Jennifer L; Wade, Shari L; Walz, Nicolay C; Cassedy, Amy; Stevens, M Hank; Yeates, Keith O; Taylor, H Gerry

    2011-11-01

    The goal of this study was to examine how parenting style (authoritarian, authoritative, permissive) and family functioning are related to behavioral aspects of executive function following traumatic brain injury (TBI) in young children. Participants included 75 children with TBI and 97 children with orthopedic injuries (OI), ages 3-7 years at injury. Pre-injury parenting behavior and family functioning were assessed shortly after injury, and postinjury executive functions were assessed using the Behavior Rating Inventory of Executive Functioning (BRIEF; Gioia & Isquith, 2004) at 6, 12, and 18 months postinjury. Mixed model analyses, using pre-injury executive functioning (assessed by the BRIEF at baseline) as a covariate, examined the relationship of parenting style and family characteristics to executive functioning in children with moderate and severe TBI compared to OI. Among children with moderate TBI, higher levels of authoritarian parenting were associated with greater executive difficulties at 12 and 18 months following injury. Permissive and authoritative parenting styles were not significantly associated with postinjury executive skills. Finally, fewer family resources predicted more executive deficits across all of the groups, regardless of injury type. These findings provide additional evidence regarding the role of the social and familial environment in emerging behavior problems following childhood TBI.

  17. Parenting Style Is Related to Executive Dysfunction After Brain Injury in Children

    Science.gov (United States)

    Potter, Jennifer L.; Wade, Shari L.; Walz, Nicolay C.; Cassedy, Amy; Yeates, Keith O.; Stevens, M. Hank; Taylor, H. Gerry

    2013-01-01

    Objective The goal of this study was to examine how parenting style (authoritarian, authoritative, permissive) and family functioning are related to behavioral aspects of executive function following traumatic brain injury (TBI) in young children. Method Participants included 75 children with TBI and 97 children with orthopedic injuries (OI), ages 3–7 years at injury. Pre-injury parenting behavior and family functioning were assessed shortly after injury, and postinjury executive functions were assessed using the Behavior Rating Inventory of Executive Functioning (BRIEF; Gioia & Isquith, 2004) at 6, 12, and 18 months postinjury. Mixed model analyses, using pre-injury executive functioning (assessed by the BRIEF at baseline) as a covariate, examined the relationship of parenting style and family characteristics to executive functioning in children with moderate and severe TBI compared to OI. Results Among children with moderate TBI, higher levels of authoritarian parenting were associated with greater executive difficulties at 12 and 18 months following injury. Permissive and authoritative parenting styles were not significantly associated with postinjury executive skills. Finally, fewer family resources predicted more executive deficits across all of the groups, regardless of injury type. Conclusion These findings provide additional evidence regarding the role of the social and familial environment in emerging behavior problems following childhood TBI. PMID:21928918

  18. Conceptualization and Operationalization of Executive Function

    Science.gov (United States)

    Baggetta, Peter; Alexander, Patricia A.

    2016-01-01

    Executive function is comprised of different behavioral and cognitive elements and is considered to play a significant role in learning and academic achievement. Educational researchers frequently study the construct. However, because of its complexity functionally, the research on executive function can at times be both confusing and…

  19. Challenging executive dominance in European democracy

    NARCIS (Netherlands)

    Curtin, D.

    2014-01-01

    Executive dominance in the contemporary EU is part of a wider migration of executive power towards types of decision making that eschew electoral accountability and popular democratic control. This democratic gap is fed by far-going secrecy arrangements and practices exercised in a concerted fashion

  20. Challenging Executive Dominance in European Democracy

    NARCIS (Netherlands)

    Curtin, D.

    2013-01-01

    Executive dominance in the contemporary EU is part of a wider migration of executive power towards types of decision making that eschew electoral accountability and popular democratic control. This democratic gap is fed by far‐going secrecy arrangements and practices exercised in a concerted fashion

  1. Ten Years of Change in Executive Education.

    Science.gov (United States)

    Bolt, James F.

    1993-01-01

    As recently as the 1980s, most companies did not pay much attention to executive education. In the 1990s, many see executive education as a must for revamping competitive strategies, increasing productivity, improving quality, reducing cycle time, and revitalizing corporate culture. (Author/JOW)

  2. Financial Management for Childcare Executive Officers.

    Science.gov (United States)

    Foster-Jorgensen, Karen; Harrington, Angela

    This handbook is designed to assist childcare executive officers (CEOs) in managing the finances of their programs. The guide is divided into five sections. Section 1, "Financial Entrepreneurship," advocates the adoption of an entrepreneurial spirit in directors and recommends: (1) becoming the Chief Executive Officer of the program; (2) actively…

  3. Understanding the Executive Functioning Heterogeneity in Schizophrenia

    Science.gov (United States)

    Raffard, Stephane; Bayard, Sophie

    2012-01-01

    Schizophrenia is characterized by heterogeneous brain abnormalities involving cerebral regions implied in the executive functioning. The dysexecutive syndrome is one of the most prominent and functionally cognitive features of schizophrenia. Nevertheless, it is not clear to what extend executive deficits are heterogeneous in schizophrenia…

  4. 32 CFR 724.702 - Executive management.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Executive management. 724.702 Section 724.702 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Organization of the Naval Discharge Review Board § 724.702 Executive management. The...

  5. Design review of the SYVAC Executive

    International Nuclear Information System (INIS)

    Lane, G.D.

    1985-01-01

    The report documents the current SYVAC Executive design. Eight criteria for evaluating aspects of the design as objectively as possible are described as well as the results of applying them. Principal benefits arising from implementation of design recommendations are perceived to be improved maintainability and better delineation of the interface between the Executive and SYVAC submodels. (author)

  6. Neural modeling of prefrontal executive function

    Energy Technology Data Exchange (ETDEWEB)

    Levine, D.S. [Univ. of Texas, Arlington, TX (United States)

    1996-12-31

    Brain executive function is based in a distributed system whereby prefrontal cortex is interconnected with other cortical. and subcortical loci. Executive function is divided roughly into three interacting parts: affective guidance of responses; linkage among working memory representations; and forming complex behavioral schemata. Neural network models of each of these parts are reviewed and fit into a preliminary theoretical framework.

  7. Heavy-metal-induced reactive oxygen species: phytotoxicity and physicochemical changes in plants.

    Science.gov (United States)

    Shahid, Muhammad; Pourrut, Bertrand; Dumat, Camille; Nadeem, Muhammad; Aslam, Muhammad; Pinelli, Eric

    2014-01-01

    As a result of the industrial revolution, anthropogenic activities have enhanced there distribution of many toxic heavy metals from the earth's crust to different environmental compartments. Environmental pollution by toxic heavy metals is increasing worldwide, and poses a rising threat to both the environment and to human health.Plants are exposed to heavy metals from various sources: mining and refining of ores, fertilizer and pesticide applications, battery chemicals, disposal of solid wastes(including sewage sludge), irrigation with wastewater, vehicular exhaust emissions and adjacent industrial activity.Heavy metals induce various morphological, physiological, and biochemical dysfunctions in plants, either directly or indirectly, and cause various damaging effects. The most frequently documented and earliest consequence of heavy metal toxicity in plants cells is the overproduction of ROS. Unlike redox-active metals such as iron and copper, heavy metals (e.g, Pb, Cd, Ni, AI, Mn and Zn) cannot generate ROS directly by participating in biological redox reactions such as Haber Weiss/Fenton reactions. However, these metals induce ROS generation via different indirect mechanisms, such as stimulating the activity of NADPH oxidases, displacing essential cations from specific binding sites of enzymes and inhibiting enzymatic activities from their affinity for -SH groups on the enzyme.Under normal conditions, ROS play several essential roles in regulating the expression of different genes. Reactive oxygen species control numerous processes like the cell cycle, plant growth, abiotic stress responses, systemic signalling, programmed cell death, pathogen defence and development. Enhanced generation of these species from heavy metal toxicity deteriorates the intrinsic antioxidant defense system of cells, and causes oxidative stress. Cells with oxidative stress display various chemical,biological and physiological toxic symptoms as a result of the interaction between ROS and

  8. Project Execution Plan, Rev. 3

    International Nuclear Information System (INIS)

    IT Corporation, Las Vegas

    2002-01-01

    This plan addresses project activities encompassed by the U.S. Department of Energy's (DOE's), National Nuclear Security Administration Nevada Operations Office, Environmental Restoration Division and conforms to the requirements contained in the Life-Cycle Asset Management, DOE Order 430.1A; The Joint Program Office Policy on Project Management in Support of DOE Order 430.1; Program and Project Management for the Acquisition of Capital Assets, DOE Order 413.3; the Project Execution and Engineering Management Planning Guide, GPG-FM-010; and other applicable Good Practice Guides; and the FY 2001 Integrated Planning, Accountability, and Budgeting System Policy Guidance. The plan also reflects the milestone philosophies of the Federal Facility Agreement and Consent Order, as agreed to by the State of Nevada, the DOE, and the U.S. Department of Defense; and traditional project management philosophies such as the development of life-cycle costs, schedules, and work scope; identification o f roles and responsibilities; and baseline management and controls

  9. Executive function in adolescents with Down Syndrome.

    Science.gov (United States)

    Lanfranchi, S; Jerman, O; Dal Pont, E; Alberti, A; Vianello, R

    2010-04-01

    The present work is aimed at analysing executive function (EF) in adolescents with Down Syndrome (DS). So far, EF has been analysed mainly in adults with DS, showing a pattern of impairment. However, less is known about children and adolescents with this syndrome. Studying adolescents with DS might help us better understand whether performances on EF tasks of individuals with DS are determined by age or by Alzheimer disease, as some studies suggest, or whether their performances are directly related to DS cognitive profile. A battery of EF tasks assessing set shifting, planning/problem-solving, working memory, inhibition/perseveration and fluency, as well as a tasks assessing sustained attention has been administered to a group of 15 adolescents with DS and 15 typically developing children matched for mental age. All EF tasks were selected from previous studies with individuals with intellectual disabilities or from developmental literature and are thought to be useful for the samples considered. The present results revealed that the group of individuals with DS performed at a significantly lower level on tasks assessing set shifting, planning/problem-solving, working memory and inhibition/perseveration, but not on the tasks assessing fluency. In addition, individuals with DS demonstrated a greater number of errors and less strategy use for the sustained attention task. The results suggest a broad impairment in EF in adolescents with DS, and are consistent with several similar studies conducted with adults with DS. We assume that EF deficit is a characteristic of DS.

  10. Autism Spectrum Disorder and intact executive functioning.

    Science.gov (United States)

    Ferrara, R; Ansermet, F; Massoni, F; Petrone, L; Onofri, E; Ricci, P; Archer, T; Ricci, S

    2016-01-01

    Earliest notions concerning autism (Autism Spectrum Disorders, ASD) describe the disturbance in executive functioning. Despite altered definition, executive functioning, expressed as higher cognitive skills required complex behaviors linked to the prefrontal cortex, are defective in autism. Specific difficulties in children presenting autism or verbal disabilities at executive functioning levels have been identified. Nevertheless, the developmental deficit of executive functioning in autism is highly diversified with huge individual variation and may even be absent. The aim of the present study to examine the current standing of intact executive functioning intact in ASD. Analysis of ASD populations, whether high-functioning, Asperger's or autism Broad Phenotype, studied over a range of executive functions including response inhibition, planning, cognitive flexibility, cognitive inhibition, and alerting networks indicates an absence of damage/impairment compared to the typically-developed normal control subjects. These findings of intact executive functioning in ASD subjects provide a strong foundation on which to construct applications for growth environments and the rehabilitation of autistic subjects.

  11. Pension benefits of executive directors : A comparative study of general retailers between 2006-2010

    OpenAIRE

    Condric, Tomislav; Tomic, Katarina

    2012-01-01

    Several recent corporate governance scandals relate to non-disclosure or high amounts of pension benefits given to executive directors. The lack of disclosure and transparency has gained pensions benefits greater attention as a significant part of the total remuneration received by executive directors. Due to the associated problems there is a greater need for better disclosure and in turn heightened transparency towards shareholders.   This qualitative case study focuses on general retailers...

  12. Using Planning, Scheduling and Execution for Autonomous Mars Rover Operations

    Science.gov (United States)

    Estlin, Tara A.; Gaines, Daniel M.; Chouinard, Caroline M.; Fisher, Forest W.; Castano, Rebecca; Judd, Michele J.; Nesnas, Issa A.

    2006-01-01

    With each new rover mission to Mars, rovers are traveling significantly longer distances. This distance increase raises not only the opportunities for science data collection, but also amplifies the amount of environment and rover state uncertainty that must be handled in rover operations. This paper describes how planning, scheduling and execution techniques can be used onboard a rover to autonomously generate and execute rover activities and in particular to handle new science opportunities that have been identified dynamically. We also discuss some of the particular challenges we face in supporting autonomous rover decision-making. These include interaction with rover navigation and path-planning software and handling large amounts of uncertainty in state and resource estimations. Finally, we describe our experiences in testing this work using several Mars rover prototypes in a realistic environment.

  13. Investigation on by-products of bioenergy systems (anaerobic digestion and gasification) as potential crop nutrient using FTIR, XRD, SEM analysis and phyto-toxicity test.

    Science.gov (United States)

    Kataki, Sampriti; Hazarika, Samarendra; Baruah, D C

    2017-07-01

    Success and acceptability of the bio energy conversion technology to a large extent depend upon management of the inevitable by-products generated during the conversion process. By-products can be considered favourable as organic fertilizer as they retain nutrients with varying composition depending upon input biomass. However, characteristics of these heterogeneous resources with respect to feedstock and processing conditions have to be assessed to state on their agricultural and environmental benefits. Therefore, 3 types of anaerobic digestion by-products (digestate) from surplus biomass viz. cow dung, Ipomoea carnea:cow dung (60:40 dry weight basis) and rice straw:green gram stover:cow dung (30:30:40 dry weight basis) and one gasification by-product (biochar) from rice husk are considered to understand the fertilizer prospects. Considering 3 potential application options, digestate from each feedstock option was further processed as separated solid, separated liquid and ash from solid digestates. Thus, a total of 10 by-products were investigated for understanding their prospects as fertilizer using Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X ray Spectroscopy (EDX) and phyto-toxicity test to have a broad insight in terms of their organic, mineral, elemental composition, morphological feature and potential phyto-toxicity. In general, irrespective of origin of feedstock, solid digestate, ash digestate and char showed similarity in terms of composition of functional groups with some degree of variation in relative content as reflected by FTIR analysis. Dominance of organic functional groups in separated solid digestates compared to liquid fraction indicated the former as favourable organic amendments. Quartz was the prevalent mineral phase in all separated solid, ash digestate and rice husk char. Digestates in ash phase represent more concentrated plant nutrient source with

  14. The role of tailored biochar in increasing plant growth, and reducing bioavailability, phytotoxicity, and uptake of heavy metals in contaminated soil.

    Science.gov (United States)

    Mohamed, Badr A; Ellis, Naoko; Kim, Chang Soo; Bi, Xiaotao

    2017-11-01

    Microwave-assisted catalytic pyrolysis was investigated using K 3 PO 4 and clinoptilolite to enhance biochar sorption affinity for heavy metals. The performance of resulting biochar samples was characterized through their effects on plant growth, bioavailability, phytotoxicity, and uptake of heavy metals in a sandy soil contaminated with Pb, Ni, and Co. The produced biochars have high cation-exchange capacity (CEC) and surface area, and rich in plant nutrients, which not only reduced heavy metals (Pb, Ni, and Co), bioavailability and phytotoxicity, but also increased plant growth rate by up to 145%. The effectiveness of biochar in terms of reduced phytotoxicity and plant uptake of heavy metals was further improved by mixing K 3 PO 4 and clinoptilolite with biomass through microwave pyrolysis. This may be due to the predominance of different mechanisms as 10KP/10Clino biochar has the highest micropore surface area (405 m 2 /g), high concentrations of K (206 g/kg), Ca (26.5 g/kg), Mg (6.2 g/kg) and Fe (11.9 g/kg) for ion-exchange and high phosphorus content (79.8 g/kg) for forming insoluble compounds with heavy metals. The largest wheat shoot length (143 mm) and lowest extracted amounts of Pb (107 mg/kg), Ni (2.4 mg/kg) and Co (63.9 mg/kg) were also obtained by using 10KP/10Clino biochar at 2 wt% load; while the smallest shoot length (68 mm) and highest extracted amounts of heavy metals (Pb 408 mg/kg, Ni 15 mg/kg and Co 148 mg/kg) for the samples treated with biochars were observed for soils mixed with 1 wt% 10Clino biochar. Strong negative correlations were also observed between biochar micropore surface area, CEC and the extracted amounts of heavy metals. Microwave-assisted catalytic pyrolysis of biomass has a great potential for producing biochar with high sorption affinity for heavy metals and rich nutrient contents using properly selected catalysts/additives that can increase microwave heating rate and improve biochar and bio-oil properties

  15. EMI Execution Service Specification 1.0

    CERN Document Server

    Schuller, B. (JUELICH); Smirnova, O (Lund University); Konstantinov, A. (Oslo University); Skou Andersen, M. (University of Copenhagen); Riedel, M. (JUELICH); Memon, A.S. (JUELICH); Memon, M.S. (JUELICH); Zangrando, L. (INFN); Sgaravatto, M. (INFN); Frizziero, E. (INFN)

    2010-01-01

    This document provides the interface specification, including related data models such as state model, activity description, resource and activity information, of an execution service, matching the needs of the EMI production middleware stack composed of ARC, gLite and UNICORE components. This service therefore is referred to as the EMI Execution Service (or “ES” for short). This document is a continuation of the work previously known as the GENEVA, then AGU (“ARC, gLite UNICORE”), then PGI execution service.

  16. The Determination of Phytotoxicity.

    Science.gov (United States)

    1981-01-01

    chemicals applied to the soil. Weeds 13:185-190. L. ,aberg, J.J. and C.V. Cutting , eds. 1977. Environmental Effects on Crop ?hysiologv. 5th Long Astiton...19 7 1. " ElvIene product ion from ozone injured plants . Environ. del I I it L1 . I k [it I K. Dec line and recovery ,f petunia dove lOpntOnt from

  17. 29 CFR 541.100 - General rule for executive employees.

    Science.gov (United States)

    2010-07-01

    ... REGULATIONS DEFINING AND DELIMITING THE EXEMPTIONS FOR EXECUTIVE, ADMINISTRATIVE, PROFESSIONAL, COMPUTER AND OUTSIDE SALES EMPLOYEES Executive Employees § 541.100 General rule for executive employees. (a) The term...

  18. 76 FR 69770 - Senior Executive Service Performance Review Board

    Science.gov (United States)

    2011-11-09

    ... OFFICE OF PERSONNEL MANAGEMENT Senior Executive Service Performance Review Board AGENCY: Office of... of a senior executive's performance by the supervisor, and considers recommendations to the appointing authority regarding the performance of the senior executive. Office of Personnel Management. John...

  19. 78 FR 28243 - Senior Executive Service; Performance Review Board; Members

    Science.gov (United States)

    2013-05-14

    ... NATIONAL CAPITAL PLANNING COMMISSION Senior Executive Service; Performance Review Board; Members AGENCY: National Capital Planning Commission. ACTION: Notice of Members of Senior Executive Service... Senior Executive Service. The PRB established for the National Capital Planning Commission also makes...

  20. 76 FR 29013 - Senior Executive Service; Performance Review Board; Members

    Science.gov (United States)

    2011-05-19

    ... NATIONAL CAPITAL PLANNING COMMISSION Senior Executive Service; Performance Review Board; Members AGENCY: National Capital Planning Commission. ACTION: Notice of Members of Senior Executive Service... Senior Executive Service. The PRB established for the National Capital Planning Commission also makes...

  1. 78 FR 41191 - Senior Executive Service Performance Review Board

    Science.gov (United States)

    2013-07-09

    ... DEPARTMENT OF TRANSPORTATION Surface Transportation Board Senior Executive Service Performance... Transportation Board (STB) publishes the names of the Persons selected to serve on its Senior Executive Service... performance appraisal system making senior executives accountable for organizational and individual goal...

  2. 77 FR 54570 - Senior Executive Service Performance Review Board

    Science.gov (United States)

    2012-09-05

    ... DEFENSE NUCLEAR FACILITIES SAFETY BOARD Senior Executive Service Performance Review Board AGENCY... the Defense Nuclear Facilities Safety Board (DNFSB) Senior Executive Service (SES) Performance Review.... The PRB shall review and evaluate the initial summary rating of the senior executive's performance...

  3. 75 FR 62501 - Senior Executive Service Performance Review Board: Update

    Science.gov (United States)

    2010-10-12

    ... AGENCY FOR INTERNATIONAL DEVELOPMENT Senior Executive Service Performance Review Board: Update... Development, Office of Inspector General's Senior Executive Service Performance Review Board. DATES: September... reference-- USAID OIG Senior Executive Service (SES) Performance Review Board). SUPPLEMENTARY INFORMATION: 5...

  4. Potencial fitotóxico de Dicranopteris flexuosa (Schrad. Underw. (Gleicheniaceae Phytotoxic potential of Dicranopteris flexuosa (Schrad. Underw. (Gleicheniaceae

    Directory of Open Access Journals (Sweden)

    Valerí Schmidt da Silva

    2011-03-01

    Full Text Available O objetivo deste trabalho foi determinar o potencial fitotóxico do extrato etanólico bruto e das frações semipurificadas de Dicranopteris flexuosa por meio de bioensaios de germinação e crescimento de Lactuca sativa L. (alface, Lycopersicon esculentum L. (tomate, Allium cepa L. (cebola e Triticum aestivum L. (trigo em laboratório e casa de vegetação e quantificar o teor total de fenóis e flavonóides dos extratos e frações. Nos bioensaios realizados em laboratório foram utilizadas quatro concentrações (0, 250, 500, 1000 mg L-1, com quatro repetições de 50 sementes. A análise dos resultados indica redução da velocidade e/ou inibição da germinação, estímulo do crescimento da raiz das eudicotiledôneas e inibição da raiz adventícia das monocotiledôneas estudadas. Nos bioensaios realizados em casa de vegetação foram utilizadas as mesmas concentrações dos bioensaios em laboratório, com oito repetições de cinco sementes por vaso. A análise dos resultados indica que o comprimento da raiz foi afetado pelo extrato etanólico bruto, ocorrendo estímulo em tomate e inibição em cebola e trigo. A produção de massa seca da parte aérea foi estimulada na menor concentração em alface e trigo. A fração acetato de etila foi a que apresentou os maiores teores de fenóis e flavonóides totais. Embora os resultados sejam preliminares, observa-se que o extrato etanólico e as frações semipurificadas de D. flexuosa também contêm substâncias que interferem no crescimento das plântulas de alface, tomate, cebola e trigo.This work aimed to determine the phytotoxic potential of crude ethanol extract and semipurified fractions of Dicranopteris flexuosa on the germination and growth of Lactuca sativa L. (lettuce, Lycopersicon esculentum L. (tomato, Allium cepa L. (onion and Triticum aestivum L. (wheat in laboratory and greenhouse bioassays and determine total phenolic and flavonoid content. For the tests carried out in

  5. Statistical optimization of growth medium for the production of the entomopathogenic and phytotoxic cyclic depsipeptide beauvericin from Fusarium oxysporum KFCC 11363P.

    Science.gov (United States)

    Lee, Hee-Seok; Song, Hyuk-Hwan; An, Joong-Hoon; Shin, Cha-Gyun; Lee, Gung Pyo; Lee, Chan

    2008-01-01

    The production of the entomopathogenic and phytotoxic cyclic depsipeptide beauvericin (BEA) was studied in submerged cultures of Fusarium oxysporum KFCC 11363P isolated in Korea. The influences of various factors on mycelia growth and BEA production were examined in both complete and chemically defined culture media. The mycelia growth and BEA production were highest in Fusarium defined medium. The optimal carbon and nitrogen sources for maximizing BEA production were glucose and NaNO3, respectively. The carbon/ nitrogen ratio for maximal production of BEA was investigated using response surface methodology (RSM). Equations derived by differentiation of the RSM model revealed that the production of BEA was maximal when using 108 mM glucose and 25 mM NaNO3.

  6. Executive Coaching Practices in the Adult Workplace

    Science.gov (United States)

    Campone, Francine

    2015-01-01

    This chapter provides an overview of key principles and practices in executive coaching. Coaching is discussed as a reflective learning opportunity and offers the theoretical grounding, strategies, and case studies for each of four key elements of a coaching engagement.

  7. Women School Executives Get Serious about Success.

    Science.gov (United States)

    Rist, Marilee C.

    1984-01-01

    Summarizes the business and discussions of the Chicago convention of the National Conference of Women School Executives. Includes tips on how women can swim in the shark-infested waters of administration--and survive. (JW)

  8. Charles River Residual Designation: Executive Summary

    Science.gov (United States)

    Read an executive summary of the Record of Decision's preliminary decision by the Regional Administrator of EPA Region 1 that storm water permits are needed to address serious water quality problems in the Charles River.

  9. Stateless and stateful implementations of faithful execution

    Science.gov (United States)

    Pierson, Lyndon G; Witzke, Edward L; Tarman, Thomas D; Robertson, Perry J; Eldridge, John M; Campbell, Philip L

    2014-12-16

    A faithful execution system includes system memory, a target processor, and protection engine. The system memory stores a ciphertext including value fields and integrity fields. The value fields each include an encrypted executable instruction and the integrity fields each include an encrypted integrity value for determining whether a corresponding one of the value fields has been modified. The target processor executes plaintext instructions decoded from the ciphertext while the protection engine is coupled between the system memory and the target processor. The protection engine includes logic to retrieve the ciphertext from the system memory, decrypt the value fields into the plaintext instructions, perform an integrity check based on the integrity fields to determine whether any of the corresponding value fields have been modified, and provide the plaintext instructions to the target processor for execution.

  10. Assessment of procurement methods used for executing ...

    African Journals Online (AJOL)

    Assessment of procurement methods used for executing maintenance works in Lagos state. ... Ethiopian Journal of Environmental Studies and Management ... Others are risk allocation, price competition and flexibility of contract. Finally, better ...

  11. Renewal and change for health care executives.

    Science.gov (United States)

    Burke, G C; Bice, M O

    1991-01-01

    Health care executives must consider renewal and change within their own lives if they are to breathe life into their own institutions. Yet numerous barriers to executive renewal exist, including time pressures, fatigue, cultural factors, and trustee attitudes. This essay discusses such barriers and suggests approaches that health care executives may consider for programming renewal into their careers. These include self-assessment for professional and personal goals, career or job change, process vs. outcome considerations, solitude, networking, lifelong education, surrounding oneself with change agents, business travel and sabbaticals, reading outside the field, physical exercise, mentoring, learning from failures, a sense of humor, spiritual reflection, and family and friends. Renewal is a continuous, lifelong process requiring constant learning. Individual executives would do well to develop a framework for renewal in their careers and organizations.

  12. A Case Study for Executive Leadership

    Science.gov (United States)

    Hill, Phyllis J.

    1975-01-01

    A newly appointed woman dean discusses the value of a management development program involving a process of self-analysis and self-determination of leadership style and effectiveness (the University of Illinois "Executive Leadership Seminar"). (JT)

  13. Grid workflow job execution service 'Pilot'

    Science.gov (United States)

    Shamardin, Lev; Kryukov, Alexander; Demichev, Andrey; Ilyin, Vyacheslav

    2011-12-01

    'Pilot' is a grid job execution service for workflow jobs. The main goal for the service is to automate computations with multiple stages since they can be expressed as simple workflows. Each job is a directed acyclic graph of tasks and each task is an execution of something on a grid resource (or 'computing element'). Tasks may be submitted to any WS-GRAM (Globus Toolkit 4) service. The target resources for the tasks execution are selected by the Pilot service from the set of available resources which match the specific requirements from the task and/or job definition. Some simple conditional execution logic is also provided. The 'Pilot' service is built on the REST concepts and provides a simple API through authenticated HTTPS. This service is deployed and used in production in a Russian national grid project GridNNN.

  14. Grid workflow job execution service 'Pilot'

    International Nuclear Information System (INIS)

    Shamardin, Lev; Kryukov, Alexander; Demichev, Andrey; Ilyin, Vyacheslav

    2011-01-01

    'Pilot' is a grid job execution service for workflow jobs. The main goal for the service is to automate computations with multiple stages since they can be expressed as simple workflows. Each job is a directed acyclic graph of tasks and each task is an execution of something on a grid resource (or 'computing element'). Tasks may be submitted to any WS-GRAM (Globus Toolkit 4) service. The target resources for the tasks execution are selected by the Pilot service from the set of available resources which match the specific requirements from the task and/or job definition. Some simple conditional execution logic is also provided. The 'Pilot' service is built on the REST concepts and provides a simple API through authenticated HTTPS. This service is deployed and used in production in a Russian national grid project GridNNN.

  15. Helping Behavior in Executives' Global Networks

    DEFF Research Database (Denmark)

    Miller, Stewart; Mors, Marie Louise; McDonald, Michael

    2014-01-01

    Drawing on research on helping behavior in networks at the upper echelons, we develop and test theory about helping behavior in senior executive networks. We examine the location and relational dependence of the network contact. Our results reveal that executives are more likely to perceive...... insiders in their network to be helpful, but geographic location has no effect on expectations of receiving help. With regards to relational dependence: executives who are more dependent on their contacts are more likely to perceive them to be helpful. We also look at whether perceived helpfulness affects...... an executive’s willingness to engage in risky new business development -- an important performance indicator - and indeed find that those executives that perceive their networks to be helpful are more likely to be willing to take risky decisions. We test these arguments using primary data on 1845 relationships...

  16. Page | 133 LEGISLATIVE APPROVAL OF EXECUTIVE ...

    African Journals Online (AJOL)

    Fr. Ikenga

    NAUJILJ 9 (2) 2018. Page | 133 ... Keywords: Executive appointments, Legislative approval, National Assembly, Constitutional duty. 1. ... Representatives is led by a Speaker.6 The election of the leadership of the senate is entirely the affair of.

  17. 29 CFR 541.402 - Executive and administrative computer employees.

    Science.gov (United States)

    2010-07-01

    ... LABOR REGULATIONS DEFINING AND DELIMITING THE EXEMPTIONS FOR EXECUTIVE, ADMINISTRATIVE, PROFESSIONAL, COMPUTER AND OUTSIDE SALES EMPLOYEES Computer Employees § 541.402 Executive and administrative computer...

  18. Neural correlates of childhood trauma with executive function in young healthy adults.

    Science.gov (United States)

    Lu, Shaojia; Pan, Fen; Gao, Weijia; Wei, Zhaoguo; Wang, Dandan; Hu, Shaohua; Huang, Manli; Xu, Yi; Li, Lingjiang

    2017-10-03

    The aim of this study was to investigate the relationship among childhood trauma, executive impairments, and altered resting-state brain function in young healthy adults. Twenty four subjects with childhood trauma and 24 age- and gender-matched subjects without childhood trauma were recruited. Executive function was assessed by a series of validated test procedures. Localized brain activity was evaluated by fractional amplitude of low frequency fluctuation (fALFF) method and compared between two groups. Areas with altered fALFF were further selected as seeds in subsequent functional connectivity analysis. Correlations of fALFF and connectivity values with severity of childhood trauma and executive dysfunction were analyzed as well. Subjects with childhood trauma exhibited impaired executive function as assessed by Wisconsin Card Sorting Test and Stroop Color Word Test. Traumatic individuals also showed increased fALFF in the right precuneus and decreased fALFF in the right superior temporal gyrus. Significant correlations of specific childhood trauma severity with executive dysfunction and fALFF value in the right precuneus were found in the whole sample. In addition, individuals with childhood trauma also exhibited diminished precuneus-based connectivity in default mode network with left ventromedial prefrontal cortex, left orbitofrontal cortex, and right cerebellum. Decreased default mode network connectivity was also associated with childhood trauma severity and executive dysfunction. The present findings suggest that childhood trauma is associated with executive deficits and aberrant default mode network functions even in healthy adults. Moreover, this study demonstrates that executive dysfunction is related to disrupted default mode network connectivity.

  19. Management report of the executive board 2005

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This 2005 report of the executive board of the group AREVA provides information on the following five topics: 1 - asset of financial position and performance with the human resources and the environmental report. 2 - general information on the company and share capital. 3 - the regulated agreements. 4 - information regarding executive management and supervisory bodies. 5 - annual general meeting of shareholders of may 2, 2006 and financial statements and notes. (A.L.B.)

  20. Management report of the executive board 2005

    International Nuclear Information System (INIS)

    2005-01-01

    This 2005 report of the executive board of the group AREVA provides information on the following five topics: 1 - asset of financial position and performance with the human resources and the environmental report. 2 - general information on the company and share capital. 3 - the regulated agreements. 4 - information regarding executive management and supervisory bodies. 5 - annual general meeting of shareholders of may 2, 2006 and financial statements and notes. (A.L.B.)

  1. Executive Compensation and Principal-Agent Theory.

    OpenAIRE

    Garen, John E

    1994-01-01

    The empirical literature on executive compensation generally fails to specify a model of executive pay on which to base hypotheses regarding its determinants. In contrast, this paper analyzes a simple principal-agent model to determine how well it explains variations in CEO incentive pay and salaries. Many findings are consistent with the basic intuition of principle-agent models that compensation is structured to trade off incentives with insurance. However, statistical significance for some...

  2. Impact of sociodemographic variables on executive functions

    OpenAIRE

    Campanholo, Kenia Repiso; Boa, Izadora Nogueira Fonte; Hodroj, Flávia Cristina da Silva Araujo; Guerra, Glaucia Rosana Benute; Miotto, Eliane Correa; Lucia, Mara Cristina Souza de

    2017-01-01

    ABSTRACT Executive functions (EFs) regulate human behavior and allow individuals to interact and act in the world. EFs are sensitive to sociodemographic variables such as age, which promotes their decline, and to others that can exert a neuroprotective effect. Objective: To assess the predictive role of education, occupation and family income on decline in executive functions among a sample with a wide age range. Methods: A total of 925 participants aged 18-89 years with 1-28 years' education...

  3. Marketing the Masters of Executive Management program

    OpenAIRE

    Barrera, Mark A.; Karriker, Timothy W.

    2007-01-01

    MBA Professional Report The purpose of this MBA project was to review the current Masters of Executive Management education curriculum at NPS. An internal analysis of the current program was conducted to fully understand the strategic goals of the program and the existing curriculum. An environmental scan of current and potential military customers was conducted to assess requirements for junior executive education and determine whether the MEM program corresponds with these requiremen...

  4. Executive dysfunction, brain aging, and political leadership.

    Science.gov (United States)

    Fisher, Mark; Franklin, David L; Post, Jerrold M

    2014-01-01

    Decision-making is an essential component of executive function, and a critical skill of political leadership. Neuroanatomic localization studies have established the prefrontal cortex as the critical brain site for executive function. In addition to the prefrontal cortex, white matter tracts as well as subcortical brain structures are crucial for optimal executive function. Executive function shows a significant decline beginning at age 60, and this is associated with age-related atrophy of prefrontal cortex, cerebral white matter disease, and cerebral microbleeds. Notably, age-related decline in executive function appears to be a relatively selective cognitive deterioration, generally sparing language and memory function. While an individual may appear to be functioning normally with regard to relatively obvious cognitive functions such as language and memory, that same individual may lack the capacity to integrate these cognitive functions to achieve normal decision-making. From a historical perspective, global decline in cognitive function of political leaders has been alternatively described as a catastrophic event, a slowly progressive deterioration, or a relatively episodic phenomenon. Selective loss of executive function in political leaders is less appreciated, but increased utilization of highly sensitive brain imaging techniques will likely bring greater appreciation to this phenomenon. Former Israeli Prime Minister Ariel Sharon was an example of a political leader with a well-described neurodegenerative condition (cerebral amyloid angiopathy) that creates a neuropathological substrate for executive dysfunction. Based on the known neuroanatomical and neuropathological changes that occur with aging, we should probably assume that a significant proportion of political leaders over the age of 65 have impairment of executive function.

  5. Executive Functioning Heterogeneity in Pediatric ADHD.

    Science.gov (United States)

    Kofler, Michael J; Irwin, Lauren N; Soto, Elia F; Groves, Nicole B; Harmon, Sherelle L; Sarver, Dustin E

    2018-04-28

    Neurocognitive heterogeneity is increasingly recognized as a valid phenomenon in ADHD, with most estimates suggesting that executive dysfunction is present in only about 33%-50% of these children. However, recent critiques question the veracity of these estimates because our understanding of executive functioning in ADHD is based, in large part, on data from single tasks developed to detect gross neurological impairment rather than the specific executive processes hypothesized to underlie the ADHD phenotype. The current study is the first to comprehensively assess heterogeneity in all three primary executive functions in ADHD using a criterion battery that includes multiple tests per construct (working memory, inhibitory control, set shifting). Children ages 8-13 (M = 10.37, SD = 1.39) with and without ADHD (N = 136; 64 girls; 62% Caucasian/Non-Hispanic) completed a counterbalanced series of executive function tests. Accounting for task unreliability, results indicated significantly improved sensitivity and specificity relative to prior estimates, with 89% of children with ADHD demonstrating objectively-defined impairment on at least one executive function (62% impaired working memory, 27% impaired inhibitory control, 38% impaired set shifting; 54% impaired on one executive function, 35% impaired on two or all three executive functions). Children with working memory deficits showed higher parent- and teacher-reported ADHD inattentive and hyperactive/impulsive symptoms (BF 10  = 5.23 × 10 4 ), and were slightly younger (BF 10  = 11.35) than children without working memory deficits. Children with vs. without set shifting or inhibitory control deficits did not differ on ADHD symptoms, age, gender, IQ, SES, or medication status. Taken together, these findings confirm that ADHD is characterized by neurocognitive heterogeneity, while suggesting that contemporary, cognitively-informed criteria may provide improved precision for identifying a

  6. A Hybrid Parallel Execution Model for Logic Based Requirement Specifications (Invited Paper

    Directory of Open Access Journals (Sweden)

    Jeffrey J. P. Tsai

    1999-05-01

    Full Text Available It is well known that undiscovered errors in a requirements specification is extremely expensive to be fixed when discovered in the software maintenance phase. Errors in the requirement phase can be reduced through the validation and verification of the requirements specification. Many logic-based requirements specification languages have been developed to achieve these goals. However, the execution and reasoning of a logic-based requirements specification can be very slow. An effective way to improve their performance is to execute and reason the logic-based requirements specification in parallel. In this paper, we present a hybrid model to facilitate the parallel execution of a logic-based requirements specification language. A logic-based specification is first applied by a data dependency analysis technique which can find all the mode combinations that exist within a specification clause. This mode information is used to support a novel hybrid parallel execution model, which combines both top-down and bottom-up evaluation strategies. This new execution model can find the failure in the deepest node of the search tree at the early stage of the evaluation, thus this new execution model can reduce the total number of nodes searched in the tree, the total processes needed to be generated, and the total communication channels needed in the search process. A simulator has been implemented to analyze the execution behavior of the new model. Experiments show significant improvement based on several criteria.

  7. Constellation Lessons Learned Executive Summary

    Science.gov (United States)

    Thomas, L. Dale; Neubek, Deb

    2011-01-01

    This slide presentation reviews the lessons learned from the Constellation Program (CxP) and identified several factors that contributed to the inability of the CxP to meet the cost and schedule commitments. The review includes a significant section on the context in which the CxP operated since new programs are likely to experience the same constraints.

  8. Quality circles: the nurse executive as mentor.

    Science.gov (United States)

    Flarey, D L

    1991-12-01

    Changes within and around the health care environment are forcing health care executives to reexamine their managerial and leadership styles to confront the resulting turbulence. The nurse executive is charged with the profound responsibility of directing the delivery of nursing care throughout the organization. Care delivered today must be of high quality. Declining financial resources as well as personnel shortages cause the executive to be an effective innovator in meeting the increasing demands. Quality circles offer the nurse executive an avenue of recourse. Circles have been effectively implemented in the health care setting, as has been consistently documented over time. By way of a participative management approach, quality circles may lead to increased employee morale and productivity, cost savings, and decreased employee turnover rates, as well as realization of socialization and self-actualization needs. A most effective approach to their introduction would be implementation at the first-line manager level. This promotes an acceptance of the concept at the management level as well as a training course for managers to implement the process at the unit level. The nurse executive facilitates the process at the first-line manager level. This facilitation will cause a positive outcome to diffuse throughout the entire organization. Quality circles offer the nurse executive the opportunity to challenge the existing environmental turmoil and effect a positive and lasting change.

  9. Metacognition and executive functioning in Elementary School

    Directory of Open Access Journals (Sweden)

    Trinidad García

    Full Text Available This study analyzes differences in metacognitive skills and executive functioning between two groups of students (10-12 years with different levels of metacognitive knowledge (high n = 50, low n = 64. Groups were established based on students' score on a test of knowledge of strategy use. Metacognitive skills were assessed by means of self-report. Students reported the frequency with which they applied these strategies during the phases of planning, execution, and evaluation of learning. Information about student executive functioning was provided by families and teachers, who completed two parallel forms of a behavior rating scale. The results indicated that: a the group with high levels of metacognitive knowledge reported using their metacognitive skills more frequently than their peers in the other group. These differences were statistically significant in the phases of planning and execution; b both family and teachers informed of better levels of executive functioning in the students with high metacognitive knowledge. Statistically significant differences were found in planning, functional memory, focus, and sustained attention. These results show the existence of an association between different levels of metacognitive knowledge, and differences in metacognitive skills and executive functions, and suggest the need to emphasize this set of variables in order to encourage students to acquire increasing levels of control over their learning process.

  10. Statistical Symbolic Execution with Informed Sampling

    Science.gov (United States)

    Filieri, Antonio; Pasareanu, Corina S.; Visser, Willem; Geldenhuys, Jaco

    2014-01-01

    Symbolic execution techniques have been proposed recently for the probabilistic analysis of programs. These techniques seek to quantify the likelihood of reaching program events of interest, e.g., assert violations. They have many promising applications but have scalability issues due to high computational demand. To address this challenge, we propose a statistical symbolic execution technique that performs Monte Carlo sampling of the symbolic program paths and uses the obtained information for Bayesian estimation and hypothesis testing with respect to the probability of reaching the target events. To speed up the convergence of the statistical analysis, we propose Informed Sampling, an iterative symbolic execution that first explores the paths that have high statistical significance, prunes them from the state space and guides the execution towards less likely paths. The technique combines Bayesian estimation with a partial exact analysis for the pruned paths leading to provably improved convergence of the statistical analysis. We have implemented statistical symbolic execution with in- formed sampling in the Symbolic PathFinder tool. We show experimentally that the informed sampling obtains more precise results and converges faster than a purely statistical analysis and may also be more efficient than an exact symbolic analysis. When the latter does not terminate symbolic execution with informed sampling can give meaningful results under the same time and memory limits.

  11. On the impacts of working memory training on executive functioning

    Directory of Open Access Journals (Sweden)

    Tiina eSalminen

    2012-06-01

    Full Text Available Recent studies have reported improvements in a variety of cognitive functions following sole working memory (WM training. In spite of the emergence of several successful training paradigms, the scope of transfer effects has remained mixed. This is most likely due to the heterogeneity of cognitive functions that have been measured and tasks that have been applied. In the present study, we approached this issue systematically by investigating transfer effects from WM training to different aspects of executive functioning. Our training task was a demanding WM task that requires simultaneous performance of a visual and an auditory n-back task, while the transfer tasks tapped WM updating, coordination of the performance of multiple simultaneous tasks (i.e., dual-tasks and sequential tasks (i.e., task switching, and the temporal distribution of attentional processing. Additionally, we examined whether WM training improves reasoning abilities; a hypothesis that has so far gained mixed support. Following training, participants showed improvements in the trained task as well as in the transfer WM updating task. As for the other executive functions, trained participants improved in a task switching situation and in attentional processing. There was no transfer to the dual-task situation or to reasoning skills. These results therefore confirm previous findings that WM can be trained, and additionally, they show that the training effects can generalize to various other tasks tapping on executive functions.

  12. Executive function in cancer patients with posttraumatic stress disorder.

    Science.gov (United States)

    Yang, Juan; Guo, Juncheng; Jiang, Xiangling

    2017-03-01

    Background Cancer patients with posttraumatic stress disorder can lead to their noncompliant behaviors. However, less is known about the neurocognitive functioning of posttraumatic stress disorder in general cancer types or patient populations. The current study attempted to examine the prevalence of posttraumatic stress disorder and their relationships with executive function in individuals with cancer. Methods A total of 285 cancer patients with posttraumatic stress disorder and 150 healthy individuals were recruited for the present study. The Clinician Administered PTSD Scale, Tower of Hanoi, Wisconsin Card Sorting Test, and Wechsler Adult Intelligence Scale-Revised Chinese revision were administered to all participants. Results Significant differences in the score of Tower of Hanoi, Wisconsin Card Sorting Test, and Wechsler Adult Intelligence Scale-Revised Chinese revision were observed between the posttraumatic stress disorder group and the healthy control group ( p posttraumatic stress disorder symptoms and executive function. Conclusions These findings suggest that individuals with cancer-related posttraumatic stress disorder exhibit more severe impairment in executive function than healthy controls do.

  13. Executive Function and Diabetes Mellitus - A Stone Left Unturned?

    LENUS (Irish Health Repository)

    2012-01-31

    Diabetes mellitus (DM) is a chronic medical condition that is dependent upon patients self-caring and managing their condition to achieve optimal control. Adherence to medical therapy, making decisions related to lifestyle changes, and self-treating hypoglycaemia for example, require planning and organisational skills that are under the control of a specific domain of cognitive function known as executive function. Executive function has been shown by functional imaging studies such as magnetic resonance imaging to be under the influence of the frontal and prefrontal cortical system. It is now recognised that even in subjects with apparently normal cognition, DM may be associated with impaired executive function (IEF). The exact cause of IEF in DM is still not fully understood. However cerebral microvascular disease and chronic dysglycaemia have been postulated as possible factors contributing to functional neuronal dysfunction leading to IEF. IEF may adversely affect patients\\' abilities to self-manage their diabetes care, potentially cause worsening glycaemic control and difficulty managing risk factors. Several bedside assessment tools to screen for IEF are currently available and have been shown to correlate with functional status. However, more studies are needed to validate these tests against diabetes self-care assessment tools. Until then, clinicians and healthcare workers managing patients with DM should be aware of the potential for IEF in their patients as specific behaviour and education intervention may be needed to help manage patients with diabetes and IEF.

  14. Executive dysfunctions in pedophilic and nonpedophilic child molesters.

    Science.gov (United States)

    Schiffer, Boris; Vonlaufen, Corinne

    2011-07-01

    There is some evidence that child molesters show neuropsychological abnormalities which might reflect specific structural and/or functional brain alterations, but there are also inconsistencies in the existing findings which need to be clarified. Most of the different outcomes can either be explained by the fact that different types of child molesters were examined or by not having accounted for basically confounding factors such as age, education/intelligence, or criminality. The present study therefore sought to determine whether pedophilic and nonpedophilic child molesters, compared to relevant control groups, show different profiles of executive dysfunction when accounting for potentially confounding factors. The performance of 30 child molesters (15 pedophilic and 15 nonpedophilic) and 33 age- and education-matched controls (16 nonsexual offenders and 17 healthy controls) was assessed regarding several neuropsychological functions. Scores on different neurocognitive tests and semistructured diagnostical interviews. Results indicate that pedophilic child molesters exhibited less performance deficits in cognitive functioning than nonpedophilic child molesters. Compared to healthy controls and nonsexual offenders, the pedophilic child molesters only showed executive dysfunction concerning response inhibition, whereas the nonpedophilic child molesters revealed more severe dysfunction, especially on tasks associated with cognitive flexibility and verbal memory. These results enhance our knowledge about executive dysfunction associated with criminality and/or pedophilia, as they suggest different profiles of impairment between groups. In summary, data suggest that nonpedophilic child molesters showed more severe cognitive deficits than pedophilic child molesters. However, as response inhibition is associated with prefrontal (i.e., orbitofrontal) functioning, the deficits observed in both child molester groups indicate dysfunction in the orbitofrontal cortex. This

  15. Toward synthesizing executable models in biology.

    Science.gov (United States)

    Fisher, Jasmin; Piterman, Nir; Bodik, Rastislav

    2014-01-01

    Over the last decade, executable models of biological behaviors have repeatedly provided new scientific discoveries, uncovered novel insights, and directed new experimental avenues. These models are computer programs whose execution mechanistically simulates aspects of the cell's behaviors. If the observed behavior of the program agrees with the observed biological behavior, then the program explains the phenomena. This approach has proven beneficial for gaining new biological insights and directing new experimental avenues. One advantage of this approach is that techniques for analysis of computer programs can be applied to the analysis of executable models. For example, one can confirm that a model agrees with experiments for all possible executions of the model (corresponding to all environmental conditions), even if there are a huge number of executions. Various formal methods have been adapted for this context, for example, model checking or symbolic analysis of state spaces. To avoid manual construction of executable models, one can apply synthesis, a method to produce programs automatically from high-level specifications. In the context of biological modeling, synthesis would correspond to extracting executable models from experimental data. We survey recent results about the usage of the techniques underlying synthesis of computer programs for the inference of biological models from experimental data. We describe synthesis of biological models from curated mutation experiment data, inferring network connectivity models from phosphoproteomic data, and synthesis of Boolean networks from gene expression data. While much work has been done on automated analysis of similar datasets using machine learning and artificial intelligence, using synthesis techniques provides new opportunities such as efficient computation of disambiguating experiments, as well as the ability to produce different kinds of models automatically from biological data.

  16. Towards Synthesizing Executable Models in Biology

    Directory of Open Access Journals (Sweden)

    Jasmin eFisher

    2014-12-01

    Full Text Available Over the last decade, executable models of biological behaviors have repeatedly provided new scientific discoveries, uncovered novel insights, and directed new experimental avenues. These models are computer programs whose execution mechanistically simulates aspects of the cell’s behaviors. If the observed behavior of the program agrees with the observed biological behavior, then the program explains the phenomena. This approach has proven beneficial for gaining new biological insights and directing new experimental avenues. One advantage of this approach is that techniques for analysis of computer programs can be applied to the analysis of executable models. For example, one can confirm that a model agrees with experiments for all possible executions of the model (corresponding to all environmental conditions, even if there are a huge number of executions. Various formal methods have been adapted for this context, for example, model checking or symbolic analysis of state spaces. To avoid manual construction of executable models, one can apply synthesis, a method to produce programs automatically from high-level specifications. In the context of biological modelling, synthesis would correspond to extracting executable models from experimental data. We survey recent results about the usage of the techniques underlying synthesis of computer programs for the inference of biological models from experimental data. We describe synthesis of biological models from curated mutation experiment data, inferring network connectivity models from phosphoproteomic data, and synthesis of Boolean networks from gene expression data. While much work has been done on automated analysis of similar datasets using machine learning and artificial intelligence, using synthesis techniques provides new opportunities such as efficient computation of disambiguating experiments, as well as the ability to produce different kinds of models automatically from biological data.

  17. Top executive compensation and company performance in Finland

    DEFF Research Database (Denmark)

    Vittaniemi, Jukka

    1997-01-01

    The compensation of Chief Executive Officers (CEOs) has attracted a lot of attention in recent years. The current value of stock options in CEOs' compensation packages may exceed several million Finnish marks and at the same time companies are firing thousands of employees. In this paper we examine...... whether the CEOs in our sample are rewarded for good economic performance or if pay increases occur irrespective of share performance and financial performance of their firms? The sample of this study consists of 48 listed and 70 private companies over the period 1989-1993. We were able to detect...

  18. Practical experience with phaseout-oriented execution of law

    International Nuclear Information System (INIS)

    Hellenschmidt, J.G.

    1991-01-01

    The result of two years of experience with phaseout-oriented execution of law is that the original political target of the new head of the authorities - abandonment of the peaceful uses of nuclear energy in Schleswig-Holstein within 2 years on the basis of the law in force - was unachievable despite considerable efforts. This interim result can be seen as positive for the operators of nuclear power plants in Schleswig-Holstein, because despite the stringency of the nuclear supervisory authorities, which could hardly be more severe, no deficits in safety, which would have warranted decommissioning, have appeared to become obvious. (orig./HSCH) [de

  19. Verification of Java Programs using Symbolic Execution and Invariant Generation

    Science.gov (United States)

    Pasareanu, Corina; Visser, Willem

    2004-01-01

    Software verification is recognized as an important and difficult problem. We present a norel framework, based on symbolic execution, for the automated verification of software. The framework uses annotations in the form of method specifications an3 loop invariants. We present a novel iterative technique that uses invariant strengthening and approximation for discovering these loop invariants automatically. The technique handles different types of data (e.g. boolean and numeric constraints, dynamically allocated structures and arrays) and it allows for checking universally quantified formulas. Our framework is built on top of the Java PathFinder model checking toolset and it was used for the verification of several non-trivial Java programs.

  20. 8 CFR 1003.0 - Executive Office for Immigration Review.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Executive Office for Immigration Review. 1003.0 Section 1003.0 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE GENERAL PROVISIONS EXECUTIVE OFFICE FOR IMMIGRATION REVIEW § 1003.0 Executive Office for...

  1. 8 CFR 3.0 - Executive Office for Immigration Review

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Executive Office for Immigration Review 3.0 Section 3.0 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY GENERAL PROVISIONS EXECUTIVE OFFICE FOR IMMIGRATION REVIEW § 3.0 Executive Office for Immigration Review Regulations of the Executive Office for...

  2. Mismanagement Reasons of the Projects Execution Phase

    Directory of Open Access Journals (Sweden)

    Hatem Khaleefah Al-Agele

    2017-10-01

    Full Text Available The execution phase of the project is most dangerous and the most drain on the resources during project life cycle, therefore, its need to monitor and control by specialists to exceeded obstructions and achieve the project goals. The study aims to detect the actual reasons behind mismanagement of the execution phase. The study begins with theoretical part, where it deals with the concepts of project, project selection, project management, and project processes. Field part consists of three techniques: 1- brainstorming, 2- open interviews with experts and 3- designed questionnaire (with 49 reason. These reasons result from brainstorming and interviewing with experts., in order to find the real reasons behind mismanagement of the execution phase. The most important reasons which are negatively impact on management of the execution phase that proven by the study were (Inability of company to meet project requirements because it's specialized and / or large project, Multiple sources of decision and overlap in powers, Inadequate planning, Inaccurate estimation of cost, Delayed cash flows by owners, Poor performance of project manager, inefficient decision making process, and the Negative impact of people in the project area. Finally, submitting a set of recommendations which will contribute to overcome the obstructions of successful management of the execution phase.

  3. Phytotoxicity Studies of Metsulfuron-methyl, Terbuthylazine and 3, 5 -Dichlorophenol by Duckweed (Lemna minor L. Test

    Directory of Open Access Journals (Sweden)

    M. Abbaspoor

    2016-06-01

    relative growth rates of the plants were calculated. The relative growth rate (RGR of Lemna minor as a function of the xenobiotics concentration was described with a sigmoid dose- response curve (log-logistic dose-response curve and toxicity parameters as EC50 were determined. Results and Discussion: The EC50 values which derived from the log-logistic fitted curves, showed that the metsulfuron-methy is the most toxic compounds than terbuthylazine and dichlorophenole and made the significant decrease in relative growth rates (RGR of lemna at much lower concentrations than two other xenobiotics. Dichlorophenole was made less toxicity effects on lemna than others. The high toxicity probably is referred to the mode of action and detoxification pathways of xenobiotics by duckweed, more than xenobiotics concentration. Terbuthylazine is amongst the most widely used herbicides which is used as selective pre-emergence herbicide, applied generally in aqueous solutions directly to the soil, in many cases together with the spring fertilizers. The high toxicity of Metsulfuron-methyl can be referred to the fact that most plants cannot metabolize and detoxify this herbicide. Also slightly higher sensitivity of macrophytes when they exposed to metsulfuron-methyl compare to the terbuthylazine has been reported. It is necessary to more experiments be established on biodegradation pathways and also to determine if the physicochemical properties of xenobiotics play an important role in phytotoxicity. Conclusions: Metsulfuron-methyl was more toxic than terbuthylazine, and terbuthylazine itself was more toxic than dichlorophenole as expected (see the EC50 values. This high toxicity probably is referred to the mode of action of theses xenobiotics and the fate (biodegradation of these toxic compounds in duckweed more than their concentrations.

  4. Building the blocks of executive functioning: differentiating early developing processes contributing to executive functioning skills

    NARCIS (Netherlands)

    Mandell, D.J.; Ward, S.E.

    2011-01-01

    The neural processes that underlie executive function begin to develop in infancy. However, it is unclear how the behavior manifested by these processes are related or if they can be differentiated early in development. This study seeks to examine early emerging executive functioning skills in

  5. Relations Between Executive Functions and Different Symptomatic Dimensions in Obsessive Compulsive Disorder

    Directory of Open Access Journals (Sweden)

    Ana Cristina Pedron

    2015-08-01

    Full Text Available There is no consensus in the literature as to neuropsychological functioning, the severity of obsessive-compulsive symptoms (OCS and the definitions of the OCS dimensions. We conducted a cross-sectional study investigating the relationship between executive function and OCS severity in the various dimensions, according to the Dimensional Yale-Brown Obsessive-Compulsive Scale criteria. We evaluated 28 patients with OCS, using eight neuropsychological instruments to evaluate executive function. We found that OCS severity in the contamination/cleaning dimension correlates negatively with executive function, inhibitory control and attentional control. Severity in the hoarding dimension correlated positively with cognitive flexibility, visual processing and logical reasoning, whereas it correlated negatively with the capacity to develop efficient complex problem-solving strategies. There was also a positive correlation between severity in the symmetry/ordering dimension and attentional control. Our findings suggest that the profile of executive function in OCD is defined by the severity of the various OCS dimensions.

  6. TOWARD THE DOMINANCE OF THE EXECUTIVE

    Directory of Open Access Journals (Sweden)

    Danica Fink-Hafner

    2013-01-01

    Full Text Available This article examines the recent processes of globalization and (within this framework Europeanization, with a focus on the changes in national political Systems (particularly in post-communist EU member states due to the pressures of these processes. The main thesis is that national executives have been gaining power in relation to the legislative due to international pressures. The international financial and economic crisis has added to this trend as countries become more financially dependent on International centers of power which demand efficient economic liberalization from national executives as a precondition for the required international loans. The case study of Slovenia is presented from a comparative perspective (in some aspects being a deviant case so as to offer new theoretical insights into the mechanisms of strengthening the national executives.

  7. Executive functions and self-regulation.

    Science.gov (United States)

    Hofmann, Wilhelm; Schmeichel, Brandon J; Baddeley, Alan D

    2012-03-01

    Self-regulation is a core aspect of adaptive human behavior that has been studied, largely in parallel, through the lenses of social and personality psychology as well as cognitive psychology. Here, we argue for more communication between these disciplines and highlight recent research that speaks to their connection. We outline how basic facets of executive functioning (working memory operations, behavioral inhibition, and task-switching) may subserve successful self-regulation. We also argue that temporary reductions in executive functions underlie many of the situational risk factors identified in the social psychological research on self-regulation and review recent evidence that the training of executive functions holds significant potential for improving poor self-regulation in problem populations. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Empowering Muslim Women Though Executive Coaching & Mentoring

    Directory of Open Access Journals (Sweden)

    Fadila Grine

    2014-06-01

    Full Text Available This paper examines the role and effect of executive coaching and mentoring on the empowerment of Muslim women and enhancing their levels of contribution. It further substantiates the manner in which executive coaching can accommodate both the nature and needs of Muslim women while further unleashing her respective talents, creativity and skills. The study further highlights the role and significance of coaching in spheres relevant to family, as well as social and career development. This study highlights the use of the strategic technique for personal and leadership development set to explore talents, leaders and implicit abilities. Moreover, it exhibits the flexibility of self-coaching and its appropriateness for Muslim women, especially concerning self-development, which in turn influences social and institutional development. This inquiry highlights a number of practical results which emphasizes the viability and efficacy of executive coaching on personal and institutional levels as far as the making of better world for Muslim women is concerned.

  9. Career Patterns of Supply Chain Executives

    DEFF Research Database (Denmark)

    Flöthmann, Christoph; Hoberg, Kai

    2017-01-01

    career patterns for SCEs. They differ in terms of the individuals' previous professional experience, educational background, and the time they needed to arrive in an executive position. By characterizing the backgrounds and career paths of SCEs, we show that supply chain management (SCM) is truly a cross......This exploratory study analyzes the careers of 307 supply chain executives (SCEs). Motivated by career theory, our findings create new knowledge about the educational backgrounds and career paths that lead to SCE positions. Based on an optimal matching analysis, we are able to distinguish among six......-functional profession. Our findings suggest that previous staff responsibility appears to be a more important hiring criterion than extensive SCM experience. While 56% of the executives had prior staff responsibility, only 12% of the cumulated careers were actually spent inside the SCM function....

  10. File Managing and Program Execution in Web Operating Systems

    OpenAIRE

    Bravetti, Mario

    2010-01-01

    Web Operating Systems can be seen as an extension of traditional Operating Systems where the addresses used to manage files and execute programs (via the basic load/execution mechanism) are extended from local filesystem path-names to URLs. A first consequence is that, similarly as in traditional web technologies, executing a program at a given URL, can be done in two modalities: either the execution is performed client-side at the invoking machine (and relative URL addressing in the executed...

  11. 75 FR 55574 - Joint Public Roundtable on Swap Execution Facilities and Security-Based Swap Execution Facilities

    Science.gov (United States)

    2010-09-13

    ...; File No. 4-612] Joint Public Roundtable on Swap Execution Facilities and Security-Based Swap Execution Facilities AGENCY: Commodity Futures Trading Commission (``CFTC'') and Securities and Exchange Commission... discuss swap execution facilities and security-based swap execution facilities in the context of certain...

  12. The Lisbon Strategy's Empowerment of Core Executives

    DEFF Research Database (Denmark)

    Borrás, Susana; Peters, B. Guy

    2011-01-01

    This paper studies the effects of the Lisbon Strategy on the way in which national executives co-ordinate EU policy at the domestic level. Comparing seven countries (Denmark, the United Kingdom [UK], Austria, Slovenia, Spain, France and Poland) it finds evidence that the Lisbon Strategy has been...... advancing (further) centralization and politicization in national patterns of EU policy co-ordination, empowering core executives. The Lisbon Strategy's ideational elements (‘grand’ goals and politically visible targets) as well as organizational requirements (Spring Council, national programming and annual...

  13. Enhancing Writing through Strengthened Executive Function

    Directory of Open Access Journals (Sweden)

    Russell Jay Hendel

    2014-10-01

    Full Text Available We explore aspects of essay writing requiring high-level organizational capacity and executive function. The literature supports the approach that specific and focused writing-skill mastery leads to reduced anxiety and increased self-efficacy which correlates with improved writing skills. Although essay writing is a complex multi-dimensional task, two particular strategies, tree-diagram and reference methods, specifically address the organizational skills characteristic of executive function. The tree and reference methods presented in this paper address the flow of information, not content, and consequently, the methods presented in this paper apply to mathematics and English as well as to K-12 and college level.

  14. Towards a Reactive Semantic Execution Environment

    Science.gov (United States)

    Komazec, Srdjan; Facca, Federico Michele

    Managing complex and distributed software systems built on top of the service-oriented paradigm has never been more challenging. While Semantic Web Service technologies offer a promising set of languages and tools as a foundation to resolve the heterogeneity and scalability issues, they are still failing to provide an autonomic execution environment. In this paper we present an approach based on Semantic Web Services to enable the monitoring and self-management of a Semantic Execution Environment (SEE), a brokerage system for Semantic Web Services. Our approach is founded on the event-triggered reactivity paradigm in order to facilitate environment control, thus contributing to its autonomicity, robustness and flexibility.

  15. Reconfigurable manufacturing execution system for pipe cutting

    Science.gov (United States)

    Yin, Y. H.; Xie, J. Y.

    2011-08-01

    This article presents a reconfigurable manufacturing execution system (RMES) filling the gap between enterprise resource planning and resource layer for pipe-cutting production with mass customisation and rapid adaptation to dynamic market, which consists of planning and scheduling layer and executive control layer. Starting from customer's task and process requirements, the cutting trajectories are planned under generalised mathematical model able to reconfigure in accordance with various intersecting types' joint, and all tasks are scheduled by nesting algorithm to maximise the utilisation rate of rough material. This RMES for pipe cutting has been effectively implemented in more than 100 companies.

  16. Better executive function under stress mitigates the effects of recent life stress exposure on health in young adults.

    Science.gov (United States)

    Shields, Grant S; Moons, Wesley G; Slavich, George M

    2017-01-01

    Executive function is a neuropsychological construct that enables controlled cognitive processing, which has been hypothesized to enhance individuals' resilience to stress. However, little empirical work has directly examined how executive function under different conditions mitigates the negative effects of stress exposure on health. To address this issue, we recruited 110 healthy young adults and assessed their recent life stress exposure, executive function in either a stressful or non-stressful context, and current health complaints. Based on existing research, we hypothesized that individuals exhibiting better executive function following a laboratory-based stressor (but not a control task) would demonstrate weaker associations between recent stress exposure and health because they perceived recent life stressors as being less severe. Consistent with this hypothesis, better executive function during acute stress, but not in the absence of stress, was associated with an attenuated link between participants' recent life stress exposure and their current health complaints. Moreover, this attenuating effect was mediated by lesser perceptions of stressor severity. Based on these data, we conclude that better executive function under stress is associated with fewer health complaints and that these effects may occur by reducing individuals' perceptions of stressor severity. The data thus suggest the possibility of reducing stress-related health problems by enhancing executive function.

  17. Executive functions and psychiatric symptoms in drug-refractory juvenile myoclonic epilepsy.

    Science.gov (United States)

    Walsh, Jordana; Thomas, Rhys H; Church, Carla; Rees, Mark I; Marson, Anthony G; Baker, Gus A

    2014-06-01

    The pattern of executive dysfunction reported in juvenile myoclonic epilepsy (JME) resembles that of patients with cluster B personality disorders. This study examined whether executive dysfunction and maladaptive behavior reported in patients with JME are related. Sixty patients with drug-refractory JME were administered tests of intellect, memory, and executive dysfunction. Anxiety, depression, personality traits, impact of epilepsy, and perceived cognitive effects of antiepileptic drugs were measured. Half of the cohort exhibited moderate to severe anxiety symptoms. The patients performed most poorly on naming ability and inhibition switching. Duration of epilepsy exacerbated poor performance on inhibition switching. Females presented with pathological scores for neurotic and introvert traits and males for introvert traits. Abnormal personality traits and psychiatric disorders were associated with worse intellectual and executive functioning. People with extreme Eysenck Personality Scale - Brief Version (EPQ-BV) scores demonstrated the greatest level of executive impairment. Furthermore, the same degree of dysfunction was not seen in any individual with unremarkable EPQ-BV scores. This study indicates that specific patterns of executive dysfunction are related to maladaptive behavior in JME. Distinct behavioral patterns may be used to identify functional and anatomical differences between people with JME and for stratification to enable gene discovery. Copyright © 2014. Published by Elsevier Inc.

  18. Individual Differences In The Executive Control Of Attention, Memory, And Thought, And Their Associations With Schizotypy

    Science.gov (United States)

    Kane, Michael J.; Meier, Matt E.; Smeekens, Bridget A.; Gross, Georgina M.; Chun, Charlotte A.; Silvia, Paul J.; Kwapil, Thomas R.

    2016-01-01

    A large correlational study took a latent-variable approach to the generality of executive control by testing the individual-differences structure of executive-attention capabilities and assessing their prediction of schizotypy, a multidimensional construct (with negative, positive, disorganized, and paranoid factors) conveying risk for schizophrenia. Although schizophrenia is convincingly linked to executive deficits, the schizotypy literature is equivocal. Subjects completed tasks of working memory capacity (WMC), attention restraint (inhibiting prepotent responses), and attention constraint (focusing visual attention amid distractors), the latter two in an effort to fractionate the “inhibition” construct. We also assessed mind-wandering propensity (via in-task thought probes) and coefficient of variation in response times (RT CoV) from several tasks as more novel indices of executive attention. WMC, attention restraint, attention constraint, mind wandering, and RT CoV were correlated but separable constructs, indicating some distinctions among “attention control” abilities; WMC correlated more strongly with attentional restraint than constraint, and mind wandering correlated more strongly with attentional restraint, attentional constraint, and RT CoV than with WMC. Across structural models, no executive construct predicted negative schizotypy and only mind wandering and RT CoV consistently (but modestly) predicted positive, disorganized, and paranoid schizotypy; stalwart executive constructs in the schizophrenia literature — WMC and attention restraint — showed little to no predictive power, beyond restraint’s prediction of paranoia. Either executive deficits are consequences rather than risk factors for schizophrenia, or executive failures barely precede or precipitate diagnosable schizophrenia symptoms. PMID:27454042

  19. Comparing the influence of selenite (Se4+) and selenate (Se6+) on the inhibition of the mercury (Hg) phytotoxicity to pak choi.

    Science.gov (United States)

    Tran, Thi Anh Thu; Dinh, Quang Toan; Cui, Zeiwei; Huang, Jie; Wang, Dan; Wei, Tianjiao; Liang, Dongli; Sun, Xin; Ning, Ping

    2018-01-01

    Selenite (Se (IV)) and selenate (Se (IV)) have recently been demonstrated to be equally effective in inhibiting mercury (Hg) phytotoxicity to plants. This assertion is still unclear. In this study, we aimed to explore the potential effects of Se species (Se 4+ and Se 6+ ) on the inhibition of the mercury (Hg) bioavailability to pak choi in dry land. Pot experiments with exposure to different dosages of mercuric chloride (HgCl 2 ) and selenite (Na 2 SeO 3 ) or selenate (Na 2 SeO 4 ) were treated. To compare the influence of Se (IV) and Se (VI) on the bioaccumulation and bioavailability of Hg, the levels of total Hg in different pak choi (Brassica chinensis L.) tissues (roots and shoots) and the distribution changes of Hg fractions in soil before planting and after harvest were determined as well as the Hg I R values in soils (relative binding intensity) were analyzed. Results showed that application Se (IV) reduced the concentrations of Hg in pak choi roots more than Se (VI). Hg concentrations were also decreased in pak choi shoots in Se (IV) treatments, while which notably increased in Se (VI) treatments. Thus, Se (IV) plays a more important role than Se (VI) in limiting the absorption and bioaccumulation of Hg in pak choi. Moreover, this inhibition may only significantly occur when Se (IV) is at an appropriate level (2.5mg/kg). In addition, the good correlations between the proportions of mobile Hg fractions (soluble and exchangeable fractions), I R values with the Hg concentrations in plants were observed. This affirmed the importance of the Hg fractions transformation and the I R indicator of Hg in the assessment of their bioavailability. Our findings regarding the importance of Se (IV) influence in reducing Hg bioaccumulation not only provided the correct appraisal about the effect of Se species on the inhibition of the Hg phytotoxicity to pak choi in dry land, but also be a good reference for selecting Se fertilizer forms (Se 4+ or Se 6+ ). Copyright © 2017

  20. Program Execution on Reconfigurable Multicore Architectures

    Directory of Open Access Journals (Sweden)

    Sanjiva Prasad

    2016-06-01

    Full Text Available Based on the two observations that diverse applications perform better on different multicore architectures, and that different phases of an application may have vastly different resource requirements, Pal et al. proposed a novel reconfigurable hardware approach for executing multithreaded programs. Instead of mapping a concurrent program to a fixed architecture, the architecture adaptively reconfigures itself to meet the application's concurrency and communication requirements, yielding significant improvements in performance. Based on our earlier abstract operational framework for multicore execution with hierarchical memory structures, we describe execution of multithreaded programs on reconfigurable architectures that support a variety of clustered configurations. Such reconfiguration may not preserve the semantics of programs due to the possible introduction of race conditions arising from concurrent accesses to shared memory by threads running on the different cores. We present an intuitive partial ordering notion on the cluster configurations, and show that the semantics of multithreaded programs is always preserved for reconfigurations "upward" in that ordering, whereas semantics preservation for arbitrary reconfigurations can be guaranteed for well-synchronised programs. We further show that a simple approximate notion of efficiency of execution on the different configurations can be obtained using the notion of amortised bisimulations, and extend it to dynamic reconfiguration.

  1. Infant Attention and Early Childhood Executive Function

    Science.gov (United States)

    Cuevas, Kimberly; Bell, Martha Ann

    2014-01-01

    Individual differences in infant attention are theorized to reflect the speed of information processing and are related to later cognitive abilities (i.e., memory, language, and intelligence). This study provides the first systematic longitudinal analysis of infant attention and early childhood executive function (EF; e.g., working memory,…

  2. The executive MBA in information security

    CERN Document Server

    Trinckes, John J

    2009-01-01

    Supplying a complete overview of the concepts executives need to know, this book provides the tools needed to ensure your organization has an effective information security management program in place. It also includes a ready-to use security framework for developing workable programs and supplies proven tips for avoiding common pitfalls.

  3. SPAWAR Strategic Plan Execution Year 2017

    Science.gov (United States)

    2017-01-11

    Transitioned financial reporting capability into SPAWAR’s business intelligence environment reducing the number of siloed business intelligence solutions...level forums, we are highlighting it here for visibility within the 2017 Strategic Execution Guidance. We will continue to report progress via...and savings • Number of analytic users MILESTONES Deliver Enterprise Business Intelligence Reports - Workforce Management Report Build #2 (January

  4. Writing executable assertions to test flight software

    Science.gov (United States)

    Mahmood, A.; Andrews, D. M.; Mccluskey, E. J.

    1984-01-01

    An executable assertion is a logical statement about the variables or a block of code. If there is no error during execution, the assertion statement results in a true value. Executable assertions can be used for dynamic testing of software. They can be employed for validation during the design phase, and exception and error detection during the operation phase. The present investigation is concerned with the problem of writing executable assertions, taking into account the use of assertions for testing flight software. They can be employed for validation during the design phase, and for exception handling and error detection during the operation phase The digital flight control system and the flight control software are discussed. The considered system provides autopilot and flight director modes of operation for automatic and manual control of the aircraft during all phases of flight. Attention is given to techniques for writing and using assertions to test flight software, an experimental setup to test flight software, and language features to support efficient use of assertions.

  5. Executive Compensation and the Cost of Debt

    NARCIS (Netherlands)

    Kabir, Mohammed Rezaul; Li, Hao; Veld-Merkoulova, Yulia V.

    2010-01-01

    We examine how executive compensation affects the cost of debt financing. Analyzing CEO pay data from the UK, we find that debt-like and equity-like pay components have opposite effects on the cost of debt. An increase in defined benefit pensions is associated with lower bond yield spread, while an

  6. Scheduling with time-dependent execution times

    NARCIS (Netherlands)

    Woeginger, G.J.

    1995-01-01

    We consider systems of tasks where the task execution times are time-dependent and where all tasks have some common deadline. We describe how to compute in polynomial time a schedule that minimizes the number of late tasks. This answers a question raised in a recent paper by Ho, Leung and Wei.

  7. Validating Avionics Conceptual Architectures with Executable Specifications

    Directory of Open Access Journals (Sweden)

    Nils Fischer

    2012-08-01

    Full Text Available Current avionics systems specifications, developed after conceptual design, have a high degree of uncertainty. Since specifications are not sufficiently validated in the early development process and no executable specification exists at aircraft level, system designers cannot evaluate the impact of their design decisions at aircraft or aircraft application level. At the end of the development process of complex systems, e. g. aircraft, an average of about 65 per cent of all specifications have to be changed because they are incorrect, incomplete or too vaguely described. In this paper, a model-based design methodology together with a virtual test environment is described that makes complex high level system specifications executable and testable during the very early levels of system design. An aircraft communication system and its system context is developed to demonstrate the proposed early validation methodology. Executable specifications for early conceptual system architectures enable system designers to couple functions, architecture elements, resources and performance parameters, often called non-functional parameters. An integrated executable specification at Early Conceptual Architecture Level is developed and used to determine the impact of different system architecture decisions on system behavior and overall performance.

  8. Executive Compensation and the Cost of Debt

    NARCIS (Netherlands)

    Kabir, Rezaul; Liu, Hao; Veld-Merkoulova, Yulia V.

    2013-01-01

    This study examines how different components of executive compensation affect the cost of debt. We find that debt-like and equity-like pay components have differing effects: an increase in defined benefit pensions is associated with lower bond yield spread, while higher share holdings lead to higher

  9. Organ procurement from executed prisoners in China.

    Science.gov (United States)

    Sharif, A; Singh, M Fiatarone; Trey, T; Lavee, J

    2014-10-01

    Organ procurement from executed prisoners in China is internationally condemned, yet this practice continues unabated in 2014. This is despite repeated announcements from Chinese authorities that constructive measures have been undertaken to conform to accepted ethical standards. While there is unanimous agreement on the unethical nature of using organs from executed prisoners, due to its limitations on voluntary and informed consent, there is insufficient coverage of forced organ procurement from prisoners of conscience without consent. Strategies to influence positive change in China over the last few decades have failed to bring this practice to an end. While organ donation and transplantation services in China have undergone considerable structural changes in the last few years, fundamental attempts to shift practice to ethically sourced organs have floundered. In this article, we discuss the organ trade in China, reflect upon organ procurement from executed prisoners (including both capital prisoners and prisoners of conscience) and provide an overview of contradictory Chinese efforts to halt forced organ procurement from executed prisoners. Finally, we highlight current actions being taken to address this issue and offer comprehensive recommendations to bring this ethically indefensible practice to an immediate end. © Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.

  10. High-Impact Succession Management. Executive Summary

    Science.gov (United States)

    Lamoureux, Kim; Campbell, Michael; Smith, Roland

    2009-01-01

    Most companies have an opportunity to improve their succession management programs. The number one challenge for succession management (as identified by both HR leaders and executives) is developing a succession planning strategy. This comprehensive industry study sets out to determine how succession management (when done well) helps improve…

  11. Execution Management Solutions for Geographically Distributed Simulations

    NARCIS (Netherlands)

    Berg, T.W. van den; Jansen, H.G.M.; Jansen, R.E.J.; Prins, L.M.

    2009-01-01

    Managing the initialization, execution control and monitoring of HLA federates is not always straightforward, especially for a geographically distributed time managed federation. Issues include pre and post run-time data distribution and run-time data collection; starting, stopping and monitoring

  12. Central executive involvement in children's spatial memory.

    Science.gov (United States)

    Ang, Su Yin; Lee, Kerry

    2008-11-01

    Previous research with adults found that spatial short-term and working memory tasks impose similar demands on executive resources. We administered spatial short-term and working memory tasks to 8- and 11-year-olds in three separate experiments. In Experiments 1 and 2 an executive suppression task (random number generation) was found to impair performances on a short-term memory task (Corsi blocks), a working memory task (letter rotation), and a spatial visualisation task (paper folding). In Experiment 3 an articulatory suppression task only impaired performance on the working memory task. These results suggest that short-term and working memory performances are dependent on executive resources. The degree to which the short-term memory task was dependent on executive resources was expected to be related to the amount of experience children have had with such tasks. Yet we found no significant age-related suppression effects. This was attributed to differences in employment of cognitive strategies by the older children.

  13. Model Adoption Exchange Payment System: Executive Summary.

    Science.gov (United States)

    Ambrosino, Robert J.

    This executive summary provides a brief description of the Model Adoption Exchange Payment System (MAEPS), a unique payment system aimed at improving the delivery of adoption exchange services throughout the United States. Following a brief introductory overview, MAEPS is described in terms of (1) its six components (registration, listing,…

  14. News from the Staff Association Executive Committee

    CERN Multimedia

    Staff Association

    2018-01-01

    On 17 April, the Staff Council proceeded to the election of the Executive Committee of the Staff Association and the members of the Bureau. First of all, why a new election of the Executive Committee elected in April 2018 after that of December 2017 (Echo No. 281)? Quite simply because a Crisis Executive Committee with a provisional Bureau had been elected for a period from 1st January to 16 April 2018 with defined and restricted objectives (Echo No. 283). Therefore, on 17 April, G. Roy presented for election a list of 12 persons, including five members for the Bureau, who agreed to continue their work within the Executive Committee, based on an intensive programme with the following main axes: Crèche and School and in particular the establishment of a foundation; Concertation: review and relaunch of the concertation process; Finalisation of the 2015 five-yearly review; Preparation and start of the 2020 five-yearly review; Actuarial reviews of the Pension Fund and the CHIS; Internal enquiries and...

  15. Executive functions in persons with metabolic syndrome

    Directory of Open Access Journals (Sweden)

    Subotić Tatjana

    2016-01-01

    Full Text Available Modern man lyfestyle contributes to the increasing incidence of metabolic syndrome in the developed world. Prevalence of the metabolic syndrome in adults ranges from 20 to 25%, and it tends to increase. Each year, 3.2 million people around the world die from complications associated with this syndrome. Treatment involves cooperation of medical doctors of various specialties, but the decisive factor is patient motivation, given that the treatment requires significant lifestyle changes. Our hypothesis is that metabolic syndrome patients have reduced ability to plan, convert plan into action and effectively implement planned activities, showing signs of dysexecutive syndrome. The term executive functions comes from the English word 'executive', which also means the controlling, in neuropsychology reserved for high-level abilities that influence more basic abilities such as attention, perception, memory, thinking and speaking. The main objective of this study was to determine characteristics of executive functioning in patients with metabolic syndrome. The sample consisted of 61 subjects of both sexes, aged 20 to 60 years, divided into two groups - those with a diagnosis of metabolic syndrome and those without this diagnosis. The results suggest that people with metabolic syndrome showed significantly poorer performance in almost all indicators of executive functions, represented by Wisconsin Card Sorting Test (Wisconsin Card Sorting Test variables.

  16. Hawaii energy strategy: Executive summary, October 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    This is an executive summary to a report on the Hawaii Energy Strategy Program. The topics of the report include the a description of the program including an overview, objectives, policy statement and purpose and objectives; energy strategy policy development; energy strategy projects; current energy situation; modeling Hawaii`s energy future; energy forecasts; reducing energy demand; scenario assessment, and recommendations.

  17. Intergenerational Transmission of Neuropsychological Executive Functioning

    Science.gov (United States)

    Jester, Jennifer M.; Nigg, Joel T.; Puttler, Leon I.; Long, Jeffrey C.; Fitzgerald, Hiram E.; Zucker, Robert A.

    2009-01-01

    Relationships between parent and child executive functioning were examined, controlling for the critical potential confound of IQ, in a family study involving 434 children (130 girls and 304 boys) and 376 parents from 204 community recruited families at high risk for the development of substance use disorder. Structural equation modeling found…

  18. Executive Functions in Individuals with Williams Syndrome

    Science.gov (United States)

    Menghini, D.; Addona, F.; Costanzo, F.; Vicari, S.

    2010-01-01

    Background: The present study was aimed at investigating working memory (WM) and executive functions capacities in individuals with Williams syndrome (WS) as compared with mental-age matched typically developing (TD) children. Method: In order to serve the study goal, a sizeable battery of tasks tapping WM as well as attention, memory, planning,…

  19. Executive succession in English local government

    OpenAIRE

    Boyne, George A.; James, Oliver; John, Peter; Petrovsky, Nicolai

    2008-01-01

    The authors report the results of the first quantitative study of senior management turnover in English local authorities. Consistent with existing management theory, rates of executive succession were found to be higher in an adverse external environment, and where organizational performance is weak. © 2008 CIPFA.

  20. Helping Behavior in Multinational Executive Networks

    DEFF Research Database (Denmark)

    Mors, Marie Louise; Miller, Stewart; McDonald, Michael

    This study develops a framework that draws upon the socio-psychology and network literatures to explain helping behavior in an executive’s multinational network. Focusing on executives' perceptions of willingness to help, we examine network structure (geographic and organizational boundaries), st...

  1. The International Research Experience: Executive MBA Distinctiveness.

    Science.gov (United States)

    Ambrose, David M.; Pol, Louis G.

    1995-01-01

    The University of Nebraska's Executive Master's in Business Administration (MBA) program has integrated international research activities into the curriculum. The university contracted with domestic corporations to conduct studies on prospects for international business. Research assignments include assessment of competitors, economic evaluations,…

  2. 45 CFR 1700.5 - Executive Director.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Executive Director. 1700.5 Section 1700.5 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL COMMISSION ON LIBRARIES AND..., recommendation and implementation of overall plans and policies to achieve the Commission's goals. (d) To...

  3. Executive functioning: a scoping review of the occupational therapy literature.

    Science.gov (United States)

    Cramm, Heidi A; Krupa, Terry M; Missiuna, Cheryl A; Lysaght, Rosemary M; Parker, Kevin H

    2013-06-01

    Increasingly recognized as an important factor in the performance of complex, goal-directed tasks, executive functioning is understood in different ways across disciplines. The aim was to explore the ways in which executive functioning is conceptualized, discussed, described, and implied in the occupational therapy literature. A scoping review of the occupational therapy literature was conducted following Levac, Colquhoun, and O'Brien's (2010) recommended methodology. Executive functioning is described both as a set of performance component skills or processes and as the executive occupational performance inherent in complex occupations. Executive functioning is implicit in occupational performance and engagement, and some health conditions seem to be commonly associated with impaired executive functioning. Assessing executive functioning requires dynamic occupation- and performance-based assessment. Interventions targeting executive functioning are grounded in metacognitive approaches. Executive functioning is a complex construct that is conceptualized with considerable variance within the occupational therapy literature, creating barriers to effective service delivery.

  4. Executive Functioning in Highly Talented Soccer Players

    Science.gov (United States)

    Verburgh, Lot; Scherder, Erik J. A.; van Lange, Paul A.M.; Oosterlaan, Jaap

    2014-01-01

    Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9), and forty-two age-matched amateur soccer players (mean age 11.8) in the age range 8 to 16 years performed a Stop Signal task (motor inhibition), the Attention Network Test (alerting, orienting, and executive attention) and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT) on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur) as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer. PMID:24632735

  5. Executive functioning in highly talented soccer players.

    Directory of Open Access Journals (Sweden)

    Lot Verburgh

    Full Text Available Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9, and forty-two age-matched amateur soccer players (mean age 11.8 in the age range 8 to 16 years performed a Stop Signal task (motor inhibition, the Attention Network Test (alerting, orienting, and executive attention and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer.

  6. Executive abilities in children with congenital visual impairment in mid-childhood.

    Science.gov (United States)

    Bathelt, Joe; de Haan, Michelle; Salt, Alison; Dale, Naomi Jane

    2018-02-01

    The role of vision and vision deprivation in the development of executive function (EF) abilities in childhood is little understood; aspects of EF such as initiative, attention orienting, inhibition, planning and performance monitoring are often measured through visual tasks. Studying the development and integrity of EF abilities in children with congenital visual impairment (VI) may provide important insights into the development of EF and also its possible relationship with vision and non-visual senses. The current study investigates non-visual EF abilities in 18 school-age children of average verbal intelligence with VI of differing levels of severity arising from congenital disorders affecting the eye, retina, or anterior optic nerve. Standard auditory neuropsychological assessments of sustained and divided attention, phonemic, semantic and switching verbal fluency, verbal working memory, and ratings of everyday executive abilities by parents were undertaken. Executive skills were compared to age-matched typically-sighted (TS) typically-developing children and across levels of vision (mild to moderate VI [MVI] or severe to profound VI [SPVI]). The results do not indicate significant differences or deficits on direct assessments of verbal and auditory EF between the groups. However, parent ratings suggest difficulties with everyday executive abilities, with the greatest difficulties in those with SPVI. The findings are discussed as possibly reflecting increased demands of behavioral executive skills for children with VI in everyday situations despite auditory and verbal EF abilities in the typical range for their age. These findings have potential implications for clinical and educational practices.

  7. Strategic management: a new dimension of the nurse executive's role.

    Science.gov (United States)

    Johnson, L J

    1990-09-01

    The growth of corporate orientation for health care structures, with a focus on bottom-line management, has radically altered the role of nurse executives. With the organization's emphasis on performance, productivity, and results, successful nurse executives are now integrating the management of the delivery of nursing care with the management of complex corporate structures and relationships. The editor of Executive Development discusses the rapidly changing expectations and demands of the contemporary nurse executive's work. The nurse executive's role can be viewed from many perspectives: its scope, its value, its structure, its content. Content--"What does the nurse executive do that makes a real difference?"--is the focus here.

  8. Self-assembled software and method of overriding software execution

    Science.gov (United States)

    Bouchard, Ann M.; Osbourn, Gordon C.

    2013-01-08

    A computer-implemented software self-assembled system and method for providing an external override and monitoring capability to dynamically self-assembling software containing machines that self-assemble execution sequences and data structures. The method provides an external override machine that can be introduced into a system of self-assembling machines while the machines are executing such that the functionality of the executing software can be changed or paused without stopping the code execution and modifying the existing code. Additionally, a monitoring machine can be introduced without stopping code execution that can monitor specified code execution functions by designated machines and communicate the status to an output device.

  9. The contribution of executive control to semantic cognition: Convergent evidence from semantic aphasia and executive dysfunction

    OpenAIRE

    Thompson, Hannah E; Almaghyuli, Azizah; Noonan, Krist A.; Barak, Ohr; Lambon Ralph, Matthew; Jefferies, Elizabeth

    2018-01-01

    Semantic cognition, as described by the Controlled Semantic Cognition (CSC) framework (Rogers, Patterson, Jefferies, & Lambon Ralph, 2015), involves two key components: activation of coherent, generalizable concepts within a heteromodal ‘hub’ in combination with modality-specific features (spokes), and a constraining mechanism that manipulates and gates this knowledge to generate time- and task- appropriate behaviour. Executive-semantic goal representations, largely supported by executive...

  10. Phytotoxical effect of Lepidium draba L. extracts on the germination and growth of monocot (Zea mays L.) and dicot (Amaranthus retroflexus L.) seeds.

    Science.gov (United States)

    Kaya, Yusuf; Aksakal, Ozkan; Sunar, Serap; Erturk, Filiz Aygun; Bozari, Sedat; Agar, Guleray; Erez, Mehmet Emre; Battal, Peyami

    2015-03-01

    Laboratory experiments were performed to determine phytotoxic potentials of white top (Lepidium draba) methanol extracts (root, stem and leaf) on germination and early growth of corn (Zea mays) and redroot pigweed (Amaranthus retroflexus). Furthermore, the effects of different methanol extracts of L. draba on the phytohormone (indole-3-acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA) and zeatin) levels of corn and redroot pigweed were investigated. It was observed that all concentrations of methanol extracts of root, stem and leaf of L. draba inhibited germination, radicle and plumule elongation when compared with the respective controls. Besides this, the degree of inhibition was increased in concert with increasing concentrations of extracts used. On the other hand, phytohormone levels changed with the application of different extract concentrations. Comparing with the control, the GA levels significantly decreased while the ABA levels increased in all the application groups. Zeatin and IAA levels showed changes depending upon the applied extracts and concentrations. © The Author(s) 2012.

  11. Phytotoxicity assessment on corn stover biochar, derived from fast pyrolysis, based on seed germination, early growth, and potential plant cell damage.

    Science.gov (United States)

    Li, Yang; Shen, Fei; Guo, Haiyan; Wang, Zhanghong; Yang, Gang; Wang, Lilin; Zhang, Yanzong; Zeng, Yongmei; Deng, Shihuai

    2015-06-01

    The potential phytotoxicity of water extractable toxicants in a typical corn stover biochar, the product of fast pyrolysis, was investigated using an aqueous biochar extract on a soil-less bioassay with tomato plants. The biochar dosage of 0.0-16.0 g beaker(-1) resulted in an inverted U-shaped dose-response relationship between biochar doasage and seed germination/seedling growth. This indicated that tomato growth was slightly stimulated by low dosages of biochar and inhibited with higher dosages of biochar. Additionally, antioxidant enzyme activities in the roots and leaves were enhanced at lower dosages, but rapidly decreased with higher dosages of biochar. With the increased dosages of biochar, the malondialdehyde content in the roots and leaves increased, in addition with the observed morphology of necrotic root cells, suggesting that serious damage to tomato seedlings occurred. EC50 of root length inhibition occurred with biochar dosages of 9.2 g beaker(-1) (3.5th day) and 16.7 g beaker(-1) (11th day) (equivalent to 82.8 and 150.3 t ha(-1), respectively), which implied that toxicity to the early growth of tomato can potentially be alleviated as the plant grows.

  12. The combined SPE:ToxY-PAM phytotoxicity assay; application and appraisal of a novel biomonitoring tool for the aquatic environment.

    Science.gov (United States)

    Bengtson Nash, S M; Schreiber, U; Ralph, P J; Müller, J F

    2005-01-15

    Mounting concerns regarding the environmental impact of herbicides has meant a growing requirement for accurate, timely information regarding herbicide residue contamination of, in particular, aquatic systems. Conventional methods of detection remain limited in terms of practicality due to high costs of operation and the specialised information that analysis provides. A new phytotoxicity bioassay was trialled for the detection of herbicide residues in filter-purified (Milli-Q) as well as natural waters. The performance of the system, which combines solid-phase extraction (SPE) with the ToxY-PAM dual-channel yield analyser (Heinz Walz GmbH), was tested alongside the traditional method of liquid chromatography-mass spectrometry (LC-MS). The assay methodology was found to be highly sensitive (LOD 0.1 ng L(-1) diuron) with good reproducibility. The study showed that the assay protocol is time effective and can be employed for the aquatic screening of herbicide residues in purified as well as natural waters.

  13. Effect of application timing and method on efficacy and phytotoxicity of 1,3-D, chloropicrin and metam-sodium combinations in squash plasticulture.

    Science.gov (United States)

    Desaeger, Johan A; Seebold, Kenneth W; Csinos, Alex S

    2008-03-01

    Metam-sodium, 1,3-dichloropropene (1,3-D) and chloropicrin are widely used soil fumigants. Combined application of metam-sodium and 1,3-D + chloropicrin is intended to improve efficacy and broaden spectrum of control, but little is known about the effect on crop safety. This study aimed to evaluate the effects of application timing of fumigant combinations on soilborne pest and disease control (nematodes, soil fungi and weeds) and growth of squash. Two separate tests with chisel-injected and drip-applied fumigant combinations and plant-back times ranging from 1 to 4 weeks were conducted in Tifton, GA, USA, in spring and fall 2002. Fumigant combinations using 1,3-D, chloropicrin and metam-sodium were as effective as methyl bromide in controlling Meloidogyne incognita (Kofoid & White) Chitwood, Pythium irregulare Buis., Rhizoctonia solani Kühn and Cyperus esculentus L. Chisel-applied combinations were more effective in terms of root-knot nematode control than drip-applied combinations. Root-knot nematode reduced squash yields by up to 60%. Phytotoxicity problems and lower yields were observed during spring, especially following 1,3-D + chloropicrin and when plant-back periods were shorter. The main problem with fumigant alternatives to methyl bromide may not be reduced efficacy but, in particular for 1,3-D products, loss of flexibility in terms of longer plant-back periods. (c) 2008 Society of Chemical Industry.

  14. Chloromonilinic Acids C and D, Phytotoxic Tetrasubstituted 3-Chromanonacrylic Acids Isolated from Cochliobolus australiensis with Potential Herbicidal Activity against Buffelgrass (Cenchrus ciliaris).

    Science.gov (United States)

    Masi, Marco; Meyer, Susan; Clement, Suzette; Pescitelli, Gennaro; Cimmino, Alessio; Cristofaro, Massimo; Evidente, Antonio

    2017-10-27

    The fungal pathogen Cochliobolus australiensis isolated from infected leaves of the invasive weed buffelgrass (Pennisetum ciliare) was grown in vitro to evaluate its ability to produce phytotoxic metabolites that could potentially be used as natural herbicides against this weed. Two new tetrasubstituted 3-chromanonacrylic acids, named chloromonilinic acids C (1) and D (2), were isolated from the liquid cultures of C. australiensis, together with the known chloromonilinic acid B. Chloromonilinic acids C and D were characterized by spectroscopic and chemical methods as (E)-3-chloro-3-[(5-hydroxy-3-(1-hydroxy-2-methoxy-2-oxoethyl)-7-methyl-4-oxo-4H-chromen-2-yl)]acrylic acid and (Z)-3-chloro-3-[(5-hydroxy-3-(2-methoxy-2-oxoethyl)-7-methyl-4-oxo-4H-chromen-2-yl)]acrylic acid, respectively. The stereochemistry of chloromonilinic acids C and D was determined using a combination of spectroscopic and computational methods, including electronic circular dichroism. The fungus produced these compounds in two different liquid media together with cochliotoxin, radicinin, radicinol, and their 3-epimers. The radicinin-related compounds were also produced when the fungus was grown in wheat seed solid culture, but chloromonilinic acids were not found in the solid culture organic extract. All three chloromonilinic acids were toxic to buffelgrass in a seedling elongation bioassay, with significantly delayed germination and dramatically reduced radicle growth, especially at a concentration of 5 × 10 -3 M.

  15. Phytotoxicity of leaf aqueous extract of Rapanea umbellata (Mart. Mez (Primulaceae on weeds - doi: 10.4025/actasciagron.v35i2.16166

    Directory of Open Access Journals (Sweden)

    Paula Novaes

    2012-12-01

    Full Text Available Allelopathic substances can be used to develop weed control alternatives based on natural products. The objective of this study was to compare the phytotoxic activity of aqueous leaf extracts of Rapanea umbellata with the toxicity of a synthetic herbicide on the germination and growth of weed species. The weeds species barnyard grass (Echinochloa crus-galli, wild poinsettia (Euphorbia heterophylla and morning glory (Ipomoea grandifolia were used. The effects of the aqueous leaf extract of R. umbellata at concentrations of 10% and 5% (g mL-1 were compared to the control (distilled water and to the synthetic herbicide oxyfluorfen. The average weed germination time was significantly lower (p < 0.05 in control than in extract and herbicide treatments. The herbicide had more significant effects than the extract on the initial growth of the aerial part. However, the initial growth of the root part was significantly more affected by the leaf extract than by the herbicide. The extract also caused many disorders in weed root anatomy. Therefore, the leaf aqueous extract of R. umbellata showed important results that indicate that it should be bioprospected and that its allelochemicals should be purified for the discovery of natural-origin herbicides.

  16. A yearly spraying of olive mill wastewater on agricultural soil over six successive years: impact of different application rates on olive production, phenolic compounds, phytotoxicity and microbial counts.

    Science.gov (United States)

    Magdich, Salwa; Jarboui, Raja; Rouina, Béchir Ben; Boukhris, Makki; Ammar, Emna

    2012-07-15

    Olive mill wastewater (OMW) spraying effects onto olive-tree fields were investigated. Three OMW levels (50, 100 and 200 m(3)ha(-1)year(-1)) were applied over six successive years. Olive-crop yields, phenolic compounds progress, phytotoxicity and microbial counts were studied at different soil depths. Olive yield showed improvements with OMW level applied. Soil polyphenolic content increased progressively in relation to OMW levels in all the investigated layers. However, no significant difference was noted in lowest treatment rate compared to the control field. In the soil upper-layers (0-40 cm), five phenolic compounds were identified over six consecutive years of OMW-spraying. In all the soil-layers, the radish germination index exceeded 85%. However, tomato germination test values decreased with the applied OMW amount. For all treatments, microbial counts increased with OMW quantities and spraying frequency. Matrix correlation showed a strong relationship between soil polyphenol content and microorganisms, and a negative one to tomato germination index. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Executive dysfunction and the relation with behavioral problems in children with 47,XXY and 47,XXX.

    Science.gov (United States)

    van Rijn, S; Swaab, H

    2015-02-01

    Neuroimaging studies have shown that having an extra X chromosome is associated with abnormal structure and function of brain areas in the frontal lobe, which is crucially involved in executive functioning. However, there is little of knowledge of the type and severity of executive dysfunction, and the impact on emotional and behavioral problems. The present study aims to provide in this. In total, 40 children (23 boys with 47,XXY and 17 girls with 47,XXX) with an extra X chromosome and 100 non-clinical controls (47 boys and 53 girls) participated in the study. The participants were 9-18 years old. Processing speed and executive functioning were assessed using the Amsterdam Neuropsychological Testbattery (ANT) and the Dysexecutive Questionnaire (DEX). Problems in emotional and behavioral functioning were assessed with the Childhood Behavior Checklist (CBCL). Children with an extra X chromosome showed deficits in inhibition, mental flexibility, sustained attention and visual working memory. Parental report showed high levels of everyday manifestations of executive dysfunction. More severe inhibition difficulties were associated with higher levels of thought problems, aggression and rule breaking behavior. Boys and girls with an extra X chromosome could not be differentiated based on severity of executive dysfunction, however, girls had lower information processing speed than boys. These findings suggest that executive dysfunction may be part of the phenotype of children with an extra X chromosome, impacting the ability to function adequately in everyday life. Furthermore, children with impairments in inhibition may have more problems in regulating their thinking, emotions and behavior. © 2015 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  18. Executive compensation and the EVA and MVA performance of ...

    African Journals Online (AJOL)

    Kirstam

    executive compensation and different measures of financial performance. Both ... traditional accounting measures such as ROA and ROE and the newer ... as different 'lenses' to look at executive remuneration, namely the principal-agent,.

  19. Sales Target and Ethical Behaviour of Marketing Executives in the ...

    African Journals Online (AJOL)

    ... No 3 (2011) >. Log in or Register to get access to full text downloads. ... This study examined sales target for marketing executives in Nigerian banks its influence ... administered on one hundred and nineteen (119) marketing executives from

  20. Executive functions as predictors of math learning disabilities

    NARCIS (Netherlands)

    Toll, S.W.M.; van der Ven, S.H.G.; Kroesbergen, E.H.; van Luit, J.E.H.

    2011-01-01

    In the past years, an increasing number of studies have investigated executive functions as predictors of individual differences in mathematical abilities. The present longitudinal study was designed to investigate whether the executive functions shifting, inhibition, and working memory differ