Evaluation of Blue Gum Chalid Infestation Woodlots in Western Kenya

International Nuclear Information System (INIS)

Otuoma, J.; Muchiri, M.N

2007-01-01

Blue gum chalcid (BGC) Leptocybe invasa is a gall-forming wasp that belongs to the insect order Hymenoptera, family Eulophidae. It attacks a wide range of Eucalyptus species mostly between the seedling stage and five years of age. BGC causes damage to eucalyptus by forming bump-shaped galls on the leaf midribs, petioles and stems.Twisted and knobbed leaves manifest severe infestation. The aim of this study was to establish the spatial distribution of BGC and extent of host plant damage in Eucalyptus woodlots in Western Kenya. The study was carried out in six permanent sampling plots in Eucalyptus woodlots in Busia, Bungoma, Kakamega and Nyando. Trees were assessed for crown damage by estimating and classifying the density of galls on the leaves into four levels of infestation: low (greater than 50% of foliage canopy with galls and no twisted or knobbed leaves), moderate (greater than 50% of foliage with galls and less than 50% of the leaves twisted and knobbed), high (greater than 50% of the leaves twisted and knobbed, galls on the twigs and some twigs deformed and severe (greater than 50% of the twigs deformed and regeneration foliage observed). An evaluation of the pests' infestation and the extent of host plant damage indicated that, 4% of the trees and severe infestation; 5% high; 20% moderate and 70% low. Approximately 1% of trees died as a result of loss of foliage attributable to severe infestation. Other observations from the study were that the severity of BGC infestation tended to decline as trees grew older and BGC infestation retarded tree growth

Preventive efficacy of Frontline® Combo and Certifect® against Dipylidium caninum infestation of cats and dogs using a natural flea (Ctenocephalides felis infestation model

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Beugnet Frederic

2013-01-01

Full Text Available Two studies were performed to evaluate the effectiveness of two monthly topical anti-flea products for the prevention of Dipylidium caninum infestations in cats and dogs. A single treatment with Frontline® Combo spot-on for cats (fipronil-(S-methoprene and two successive monthly treatments of Certifect® for dogs (fipronil-amitraz-(S-methoprene were assessed for the prevention of D. caninum infestations following weekly challenges of treated cats or dogs with metacestode naturally-infected fleas. The rate of infestations using the model in cats versus dogs explains the choice of a 1-month trial in cats and a 2-month trial in dogs. The experimental flea-infection model resulted in a range of 22–53% of the fleas being infected by Dipylidium cysticercoids. The arithmetic mean flea counts recorded for the untreated cats ranged from 51.2 to 68. The geometric mean flea counts recorded for the Frontline Combo treated cats differed significantly (p < 0.05 from those of the untreated control cats on all assessment days. The arithmetic mean flea counts recorded for the untreated dogs ranged from 166.6 to 238.6. The geometric mean flea counts recorded for the Certifect treated dogs differed significantly (p < 0.001 from those of the untreated group on all assessment days. Frontline Combo treatment on cats provided ≥99.8% persistent anti-flea efficacy throughout the 30-day treatment period. In the dog study, the two Certifect treatments provided ≥97% persistent efficacy throughout the 60-day study. Based on the collection of expelled D. caninum proglottids by cats, 100% (6/6 of the control cats and 0% (0/6 of Frontline Combo treated cats were infested with D. caninum. Frontline Combo spot-on for cats was therefore 100% effective in preventing infection with D. caninum. In dogs, 7 out of the 8 control group dogs (87.5% produced proglottids following infestation of infected fleas, whereas 0 out of 8 dogs (0% in the treated group were infected. The

Modelling the current distribution and predicted spread of the flea species Ctenocephalides felis infesting outdoor dogs in Spain.

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Gálvez, Rosa; Musella, Vicenzo; Descalzo, Miguel A; Montoya, Ana; Checa, Rocío; Marino, Valentina; Martín, Oihane; Cringoli, Giuseppe; Rinaldi, Laura; Miró, Guadalupe

2017-09-19

The cat flea, Ctenocephalides felis, is the most prevalent flea species detected on dogs and cats in Europe and other world regions. The status of flea infestation today is an evident public health concern because of their cosmopolitan distribution and the flea-borne diseases transmission. This study determines the spatial distribution of the cat flea C. felis infesting dogs in Spain. Using geospatial tools, models were constructed based on entomological data collected from dogs during the period 2013-2015. Bioclimatic zones, covering broad climate and vegetation ranges, were surveyed in relation to their size. The models builded were obtained by negative binomial regression of several environmental variables to show impacts on C. felis infestation prevalence: land cover, bioclimatic zone, mean summer and autumn temperature, mean summer rainfall, distance to urban settlement and normalized difference vegetation index. In the face of climate change, we also simulated the future distributions of C. felis for the global climate model (GCM) "GFDL-CM3" and for the representative concentration pathway RCP45, which predicts their spread in the country. Predictive models for current climate conditions indicated the widespread distribution of C. felis throughout Spain, mainly across the central northernmost zone of the mainland. Under predicted conditions of climate change, the risk of spread was slightly greater, especially in the north and central peninsula, than for the current situation. The data provided will be useful for local veterinarians to design effective strategies against flea infestation and the pathogens transmitted by these arthropods.

Parasite infestation increases on coral reefs without cleaner fish

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Grutter, A. S.; De Brauwer, M.; Bshary, R.; Cheney, K. L.; Cribb, T. H.; Madin, E. M. P.; McClure, E. C.; Meekan, M. G.; Sun, D.; Warner, R. R.; Werminghausen, J.; Sikkel, P. C.

2018-03-01

Mutualisms are pivotal in shaping ecological communities. Iconic images of cleaner fish entering the mouths of predatory fish clients to remove ectoparasites epitomize their mutual benefit. Experimental manipulations of cleaner wrasse reveal declines in fish size and growth, and population abundance and diversity of client fishes in the absence of cleaner wrasse. Fishes grow more slowly and are less abundant and diverse on reefs without cleaner wrasse, both for larger species that are regularly cleaned and have high ectoparasite loads ("attractive species"), and for those smaller species that are rarely cleaned and are rarely infested with parasites ("unattractive species"). We therefore considered whether these previously observed declines in individual and population parameters on reefs without cleaners were related to increased ectoparasite infestation using an attractive species ( Hemigymnus melapterus, Labridae) and an unattractive species ( Pomacentrus amboinensis, Pomacentridae). Traps with these fish as a form of bait were deployed to sample blood-sucking gnathiid ectoparasites (Gnathiidae: Isopoda) on reefs from which cleaners ( Labroides dimidiatus, Labridae) have been removed for 13 yr. Cleaner fish could not enter traps to access the clients/hosts, but gnathiids could enter the traps to infest hosts; thus, this method sampled the indirect effect of cleaners on gnathiid infestation of fish. Infestation was higher on reefs without cleaners than on those with them. The effect was only detected during the daytime when cleaners are active and only on the attractive species ( H. melapterus). Thus, cleaner presence indirectly reduced fish exposure to parasites in a species that is highly susceptible to parasites, but not in one that is rarely infested with parasites. This suggests that cleaner presence indirectly reduces exposure of a common fish species to harmful parasites, which may explain some observed benefits in fishes at this location.

Factors affecting infestation by Triatoma infestans in a rural area of the humid Chaco in Argentina: a multi-model inference approach.

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Gurevitz, Juan M; Ceballos, Leonardo A; Gaspe, María Sol; Alvarado-Otegui, Julián A; Enríquez, Gustavo F; Kitron, Uriel; Gürtler, Ricardo E

2011-10-01

Transmission of Trypanosoma cruzi by Triatoma infestans remains a major public health problem in the Gran Chaco ecoregion, where understanding of the determinants of house infestation is limited. We conducted a cross-sectional study to model factors affecting bug presence and abundance at sites within house compounds in a well-defined rural area in the humid Argentine Chaco. Triatoma infestans bugs were found in 45.9% of 327 inhabited house compounds but only in 7.4% of the 2,584 sites inspected systematically on these compounds, even though the last insecticide spraying campaign was conducted 12 years before. Infested sites were significantly aggregated at distances of 0.8-2.5 km. The most frequently infested ecotopes were domiciles, kitchens, storerooms, chicken coops and nests; corrals were rarely infested. Domiciles with mud walls and roofs of thatch or corrugated tarred cardboard were more often infested (32.2%) than domiciles with brick-and-cement walls and corrugated metal-sheet roofs (15.1%). A multi-model inference approach using Akaike's information criterion was applied to assess the relative importance of each variable by running all possible (17,406) models resulting from all combinations of variables. Availability of refuges for bugs, construction with tarred cardboard, and host abundance (humans, dogs, cats, and poultry) per site were positively associated with infestation and abundance, whereas reported insecticide use showed a negative association. Ethnic background (Creole or Toba) adjusted for other factors showed little or no association. Promotion and effective implementation of housing improvement (including key peridomestic structures) combined with appropriate insecticide use and host management practices are needed to eliminate infestations. Fewer refuges are likely to result in fewer residual foci after insecticide spraying, and will facilitate community-based vector surveillance. A more integrated perspective that considers simultaneously

Factors Affecting Infestation by Triatoma infestans in a Rural Area of the Humid Chaco in Argentina: A Multi-Model Inference Approach

Science.gov (United States)

Gurevitz, Juan M.; Ceballos, Leonardo A.; Gaspe, María Sol; Alvarado-Otegui, Julián A.; Enríquez, Gustavo F.; Kitron, Uriel; Gürtler, Ricardo E.

2011-01-01

Background Transmission of Trypanosoma cruzi by Triatoma infestans remains a major public health problem in the Gran Chaco ecoregion, where understanding of the determinants of house infestation is limited. We conducted a cross-sectional study to model factors affecting bug presence and abundance at sites within house compounds in a well-defined rural area in the humid Argentine Chaco. Methodology/Principal Findings Triatoma infestans bugs were found in 45.9% of 327 inhabited house compounds but only in 7.4% of the 2,584 sites inspected systematically on these compounds, even though the last insecticide spraying campaign was conducted 12 years before. Infested sites were significantly aggregated at distances of 0.8–2.5 km. The most frequently infested ecotopes were domiciles, kitchens, storerooms, chicken coops and nests; corrals were rarely infested. Domiciles with mud walls and roofs of thatch or corrugated tarred cardboard were more often infested (32.2%) than domiciles with brick-and-cement walls and corrugated metal-sheet roofs (15.1%). A multi-model inference approach using Akaike's information criterion was applied to assess the relative importance of each variable by running all possible (17,406) models resulting from all combinations of variables. Availability of refuges for bugs, construction with tarred cardboard, and host abundance (humans, dogs, cats, and poultry) per site were positively associated with infestation and abundance, whereas reported insecticide use showed a negative association. Ethnic background (Creole or Toba) adjusted for other factors showed little or no association. Conclusions/Significance Promotion and effective implementation of housing improvement (including key peridomestic structures) combined with appropriate insecticide use and host management practices are needed to eliminate infestations. Fewer refuges are likely to result in fewer residual foci after insecticide spraying, and will facilitate community-based vector

Mistletoe effects on Scots pine decline following drought events: insights from within-tree spatial patterns, growth and carbohydrates.

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Sangüesa-Barreda, Gabriel; Linares, Juan Carlos; Camarero, J Julio

2012-05-01

Forest decline has been attributed to the interaction of several stressors including biotic factors such as mistletoes and climate-induced drought stress. However, few data exist on how mistletoes are spatially arranged within trees and how this spatial pattern is related to changes in radial growth, responses to drought stress and carbon use. We used dendrochronology to quantify how mistletoe (Viscum album L.) infestation and drought stress affected long-term growth patterns in Pinus sylvestris L. at different heights. Basal area increment (BAI) trends and comparisons between trees of three different infestation degrees (without mistletoe, ID1; moderately infested trees, ID2; and severely infested trees, ID3) were performed using linear mixed-effects models. To identify the main climatic drivers of tree growth tree-ring widths were converted into indexed chronologies and related to climate data using correlation functions. We performed spatial analyses of the 3D distribution of mistletoe individuals and their ages within the crowns of three severely infested pines to describe their patterns. Lastly, we quantified carbohydrate and nitrogen concentrations in needles and sapwood of branches from severely infested trees and from trees without mistletoe. Mistletoe individuals formed strongly clustered groups of similar age within tree crowns and their age increased towards the crown apex. Mistletoe infestation negatively impacted growth but this effect was stronger near the tree apex than in the rest of sampled heights, causing an average loss of 64% in BAI (loss of BAI was ∼51% at 1.3 m or near the tree base). We found that BAI of severely infested trees and moderately or non-infested trees diverged since 2001 and such divergence was magnified by drought. Infested trees had lower concentrations of soluble sugars in their needles than non-infested ones. We conclude that mistletoe infestation causes growth decline and increases the sensitivity of trees to drought

Occurrence and Impact of Insects in Maximum Growth Plantations

Energy Technology Data Exchange (ETDEWEB)

Nowak, J.T.; Berisford, C.W.

2001-01-01

Investigation of the relationships between intensive management practices and insect infestation using maximum growth potential studies of loblolly pine constructed over five years using a hierarchy of cultural treatments-monitoring differences in growth and insect infestation levels related to the increasing management intensities. This study shows that tree fertilization can increase coneworm infestation and demonstrated that tip moth management tree growth, at least initially.

Influence of household rat infestation on leptospira transmission in the urban slum environment.

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Costa, Federico; Ribeiro, Guilherme S; Felzemburgh, Ridalva D M; Santos, Norlan; Reis, Renato Barbosa; Santos, Andreia C; Fraga, Deborah Bittencourt Mothe; Araujo, Wildo N; Santana, Carlos; Childs, James E; Reis, Mitermayer G; Ko, Albert I

2014-12-01

The Norway rat (Rattus norvegicus) is the principal reservoir for leptospirosis in many urban settings. Few studies have identified markers for rat infestation in slum environments while none have evaluated the association between household rat infestation and Leptospira infection in humans or the use of infestation markers as a predictive model to stratify risk for leptospirosis. We enrolled a cohort of 2,003 urban slum residents from Salvador, Brazil in 2004, and followed the cohort during four annual serosurveys to identify serologic evidence for Leptospira infection. In 2007, we performed rodent infestation and environmental surveys of 80 case households, in which resided at least one individual with Leptospira infection, and 109 control households. In the case-control study, signs of rodent infestation were identified in 78% and 42% of the households, respectively. Regression modeling identified the presence of R. norvegicus feces (OR, 4.95; 95% CI, 2.13-11.47), rodent burrows (2.80; 1.06-7.36), access to water (2.79; 1.28-6.09), and un-plastered walls (2.71; 1.21-6.04) as independent risk factors associated with Leptospira infection in a household. We developed a predictive model for infection, based on assigning scores to each of the rodent infestation risk factors. Receiver operating characteristic curve analysis found that the prediction score produced a good/excellent fit based on an area under the curve of 0.78 (0.71-0.84). Our study found that a high proportion of slum households were infested with R. norvegicus and that rat infestation was significantly associated with the risk of Leptospira infection, indicating that high level transmission occurs among slum households. We developed an easily applicable prediction score based on rat infestation markers, which identified households with highest infection risk. The use of the prediction score in community-based screening may therefore be an effective risk stratification strategy for targeting control

Spatial and temporal distribution of house infestation by Triatoma infestans in the Toro Toro municipality, Potosi, Bolivia.

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Espinoza Echeverria, Jorge; Rodriguez, Antonio Nogales; Cortez, Mirko Rojas; Diotaiuti, Liléia Gonçalves; Gorla, David E

2017-02-02

Triatoma infestans is the main vector of Trypanosoma cruzi in Bolivia. The species is present both in domestic and peridomestic structures of rural areas, and in wild ecotopes of the Andean valleys and the Great Chaco. The identification of areas persistently showing low and high house infestation by the vector is important for the management of vector control programs. This study aimed at analyzing the temporal and spatial distribution of house infestation by T. infestans in the Toro Toro municipality (Potosi, Bolivia) between 2009 and 2014, and its association with environmental variables. House infestation and T. infestans density were calculated from entomological surveys of houses in the study area, using a fixed-time effort sampling technique. The spatial heterogeneity of house infestation was evaluated using the SatScan statistic. Association between house infestation with Bioclim variables (Worldclim database) and altitude was analyzed using a generalized linear model (GLM) with a logit link. Model selection was based on the Akaike information criteria after eliminating collinearity between variables using the variable inflation factor. The final model was used to create a probability map of house infestation for the Toro Toro municipality. A total of 73 communities and 16,489 house evaluation events were analyzed. Presence of T. infestans was recorded on 480 house evaluation events, giving an overall annual infestation of 2.9% during the studied period (range 1.5-5.4% in 2009 and 2012). Vector density remained at about 1.25 insects/ house. Infestation was highly aggregated in five clusters, including 11 communities. Relative risk of infestation within these clusters was 1.7-3.9 times the value for the regional average. Four environmental variables were identified as good descriptors of house infestation, explaining 57% of house infestation variability. The model allowed the estimation of a house infestation surface for the Toro Toro municipality. This

Rootstock Effects on Pistachio Trees Grown in Verticillium dahliae-Infested Soil.

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Epstein, L; Beede, R; Kaur, S; Ferguson, L

2004-04-01

ABSTRACT In a field trial in soil infested with Verticillium dahliae, we compared the yield, growth, incidence of symptoms of Verticillium wilt, and mortality of two interspecific hybrid pistachio tree rootstocks (UCBI and PGII) with the standard rootstocks: the V. dahliae-resistant and susceptible Pistacia integerrima and P. atlantica, respectively. After 10 years, the trees were destructively sampled for V. dahliae in the xylem at the graft union. The results indicate that trees on the (P. atlantica 'KAC' x P. integerrima) hybrid UCBI rootstock grew and yielded as well as those on P. integerrima. Trees on the hybrid PGII yielded the least. Analysis of variance and log-linear models indicate that in soil infested with V. dahliae, three associations significantly affect pistachio nut yield. Rootstock affects scion vigor and extent of infection. Third, the extent of infection and scion vigor are inversely associated. Although trees on the P. integerrima rootstock had the highest ratings in a visual assessment of vigor, 65% were infected with V. dahliae in the trunk in the graft region compared with 73% in P. atlantica and 25% in UCBI. Thus, P. integerrima and UCBI have at least one different mechanism for resistance to V. dahliae.

Spectral analysis of white ash response to emerald ash borer infestations

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Calandra, Laura

The emerald ash borer (EAB) (Agrilus planipennis Fairmaire) is an invasive insect that has killed over 50 million ash trees in the US. The goal of this research was to establish a method to identify ash trees infested with EAB using remote sensing techniques at the leaf-level and tree crown level. First, a field-based study at the leaf-level used the range of spectral bands from the WorldView-2 sensor to determine if there was a significant difference between EAB-infested white ash (Fraxinus americana) and healthy leaves. Binary logistic regression models were developed using individual and combinations of wavelengths; the most successful model included 545 and 950 nm bands. The second half of this research employed imagery to identify healthy and EAB-infested trees, comparing pixel- and object-based methods by applying an unsupervised classification approach and a tree crown delineation algorithm, respectively. The pixel-based models attained the highest overall accuracies.

Parasites in the fossil record: a Cretaceous fauna with isopod-infested decapod crustaceans, infestation patterns through time, and a new ichnotaxon.

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Adiël A Klompmaker

Full Text Available Parasites are common in modern ecosystems and are also known from the fossil record. One of the best preserved and easily recognisable examples of parasitism in the fossil record concerns isopod-induced swellings in the branchial chamber of marine decapod crustaceans. However, very limited quantitative data on the variability of infestation percentages at the species, genus, and family levels are available. Here we provide this type of data for a mid-Cretaceous (upper Lower Cretaceous, upper Albian reef setting at Koskobilo, northern Spain, on the basis of 874 specimens of anomurans and brachyurans. Thirty-seven specimens (4.2%, arranged in ten species, are infested. Anomurans are more heavily infested than brachyurans, variability can be high within genera, and a relationship may exist between the number of specimens and infestation percentage per taxon, possibly suggesting host-specificity. We have also investigated quantitative patterns of infestation through geological time based on 88 infested species (25 anomurans, 55 brachyurans, seven lobsters, and one shrimp, to show that the highest number of infested species can be found in the Late Jurassic, also when corrected for the unequal duration of epochs. The same Late Jurassic peak is observed for the percentage of infested decapod species per epoch. This acme is caused entirely by infested anomurans and brachyurans. Biases (taphonomic and otherwise and causes of variability with regard to the Koskobilo assemblage and infestation patterns through time are discussed. Finally, a new ichnogenus and -species, Kanthyloma crusta, are erected to accommodate such swellings or embedment structures (bioclaustrations.

Delusional infestation.

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Freudenmann, Roland W; Lepping, Peter

2009-10-01

This papers aims at familiarizing psychiatric and nonpsychiatric readers with delusional infestation (DI), also known as delusional parasitosis. It is characterized by the fixed belief of being infested with pathogens against all medical evidence. DI is no single disorder but can occur as a delusional disorder of the somatic type (primary DI) or secondary to numerous other conditions. A set of minimal diagnostic criteria and a classification are provided. Patients with DI pose a truly interdisciplinary problem to the medical system. They avoid psychiatrists and consult dermatologists, microbiologists, or general practitioners but often lose faith in professional medicine. Epidemiology and history suggest that the imaginary pathogens change constantly, while the delusional theme "infestation" is stable and ubiquitous. Patients with self-diagnosed "Morgellons disease" can be seen as a variation of this delusional theme. For clinicians, clinical pathways for efficient diagnostics and etiology-specific treatment are provided. Specialized outpatient clinics in dermatology with a liaison psychiatrist are theoretically best placed to provide care. The most intricate problem is to engage patients in psychiatric therapy. In primary DI, antipsychotics are the treatment of choice, according to limited but sufficient evidence. Pimozide is no longer the treatment of choice for reasons of drug safety. Future research should focus on pathophysiology and the neural basis of DI, as well as on conclusive clinical trials, which are widely lacking. Innovative approaches will be needed, since otherwise patients are unlikely to adhere to any study protocol.

Surveillance study of vector species on board passenger ships, Risk factors related to infestations

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Hatzoglou Chrissi

2008-03-01

Full Text Available Abstract Background Passenger ships provide conditions suitable for the survival and growth of pest populations. Arthropods and rodents can gain access directly from the ships' open spaces, can be carried in shiploads, or can be found on humans or animals as ectoparasites. Vectors on board ships may contaminate stored foods, transmit illness on board, or, introduce diseases in new areas. Pest species, ship areas facilitating infestations, and different risk factors related to infestations were identified in 21 ferries. Methods 486 traps for insects and rodents were placed in 21 ferries. Archives of Public Health Authorities were reviewed to identify complaints regarding the presence of pest species on board ferries from 1994 to 2004. A detail questionnaire was used to collect data on ship characteristics and pest control practices. Results Eighteen ferries were infested with flies (85.7%, 11 with cockroaches (52.3%, three with bedbugs, and one with fleas. Other species had been found on board were ants, spiders, butterflies, beetles, and a lizard. A total of 431 Blattella germanica species were captured in 28 (9.96% traps, and 84.2% of them were nymphs. One ship was highly infested. Cockroach infestation was negatively associated with ferries in which Hazard Analysis Critical Control Point system was applied to ensure food safety on board (Relative Risk, RR = 0.23, p = 0.03, and positively associated with ferries in which cockroaches were observed by crew (RR = 4.09, p = 0.007, no cockroach monitoring log was kept (RR = 5.00, p = 0.02, and pesticide sprays for domestic use were applied by crew (RR = 4.00, p = 0.05. Cockroach infested ships had higher age (p = 0.03. Neither rats nor mice were found on any ship, but three ferries had been infested with a rodent in the past. Conclusion Integrated pest control programs should include continuing monitoring for a variety of pest species in different ship locations; pest control measures should be more

Density, heating value, and composition of pellets made from lodgepole pine (Pinus concorta Douglas) infested with mountain pine beetle (Dendroctonus ponderosae Hopkins)

Energy Technology Data Exchange (ETDEWEB)

Zaini, P.; Kadla, J. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Wood Science; Sokansanj, S. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Chemical and Biological Engineering; Oak Ridge National Laboratory, Oak Ridge, TN (United States). Environmental Sciences Div., Bioenergy Resource and Engineering Systems; Bi, X.; Lim, C.J. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Chemical and Biological Engineering; Mani, S. [Georgia Univ., Athens, GA (United States). Faculty of Engineering; Melin, S. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Chemical and Biological Engineering; Delta Research Corp., Delta, BC (Canada)

2008-07-01

BC is currently experiencing the largest recorded mountain pine beetle (MPB) infestation in North America that has killed nearly 7 million hectares of pine. The dead trees gradually lose their suitability for dimension lumber and pulp chips due to excessive cracking and spoilage. The economic losses can be partly averted by recovering the killed wood and processing it into pellets for bioenergy and other applications. Currently, Canada exports roughly 750,000 tons of wood pellets to Europe as a fuel for heat and power. The most important physical properties of wood pellets are bulk and pellet density, heating value, moisture content, and durability. In light of the chemical and structural changes reported with MPB attack, it is important to develop engineering data on properties of MPB-affected pine for wood pellets. The objective of this study was to compare chemical composition, density, and heat value of pellets made from MPB-infested wood and to compare these properties with those measured for pellets made from uninfested wood. Chemical analysis showed minor decrease in lignin and sugar contents of pellets made from MPB wood. Pellets made from MPB-infested pine had a mean value for density larger than those made from uninfested pine but the difference was not statistically significant. Heating values of the pellets from MPB-infested wood were similar to those measured for pellets from uninfested wood. A preliminary observation of mold growth did not show any further staining or other decay fungi growth for the pellets made from MPB-infested wood. The pellets made from MPB-infested wood were found to be similar to pellets made from uninfested wood in density, heating value, and most chemical constituents. The overall conclusion was that MBP infested wood can be used to produce comparable pellets to non infested wood pellets. 37 refs., 6 tabs., 2 figs.

A First Report of Infestation by Pseudolynchia canariensis in a Herd of Pigeons in Shahrekord (Southwest of Iran)

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Pirali-Kheirabadi, Khodadad; Dehghani-Samani, Amir; Ahmadi-Baberi, Nader; Najafzadeh, Vida

2016-01-01

Background: Pigeons (Columba livia) have been kept as pet and reared for food in several countries including Iran. Ectoparasites are regarded as the basic causes of retardation in growth, lowered vitality and poor conditions of the birds. Pseudolynchia canariensis a hippoboscidae fly is one of the important ectoparasites of pigeons and is responsible for the transmission of pathogens to birds and humans same as pathogenic protozoan Haemoproteus columbae. Methods: A herd of domestic pigeons contained 50 pigeons in Shahrekord, southwest Iran was evaluated clinically infested by ectoparasites. Ectoparasites were removed. The samples were collected and then referred to the Laboratory of Parasitology of Shahrekord University, Shahrekord, Iran. Results: Usin diagnostic key for diptera fly, these flies were find P. canariensis. This is a rare report of infestation of pigeons herd by P. canariensis in Iran. The infestation rate was 40% that rate of infestation in pipers was more than females and in females was more than males. Conclusion: The rate of infested pipers was more than adults that maybe the less potential of pipers in removing of ectoparasites is reason of this higher rate. PMID:27308301

A First Report of Infestation by Pseudolynchia canariensis in a Herd of Pigeons in Shahrekord (Southwest of Iran

Directory of Open Access Journals (Sweden)

Khodadad Pirali-Kheirabadi

2016-01-01

Full Text Available Background: Pigeons (Columba livia have been kept as pet and reared for food in several countries including Iran. Ectoparasites are regarded as the basic causes of retardation in growth, lowered vitality and poor conditions of the birds. Pseudolynchia canariensis a hippoboscidae fly is one of the important ectoparasites of pigeons and is respon­sible for the transmission of pathogens to birds and humans same as pathogenic protozoan Haemoproteus columbae.Methods: A herd of domestic pigeons contained 50 pigeons in Shahrekord, southwest Iran was evaluated clinically infested by ectoparasites. Ectoparasites were removed. The samples were collected and then referred to the Laboratory of Parasitology of Shahrekord University, Shahrekord, Iran.Results: Usin diagnostic key for diptera fly, these flies were find P. canariensis. This is a rare report of infestation of pigeons herd by P. canariensis in Iran. The infestation rate was 40% that rate of infestation in pipers was more than females and in females was more than males.Conclusion: The rate of infested pipers was more than adults that maybe the less potential of pipers in removing of ectoparasites is reason of this higher rate.

Monogenean infestations and mortality in wild and cultured Red Sea fishes

Science.gov (United States)

Paperna, I.; Diamant, A.; Overstreet, R. M.

1984-03-01

Hyperinfection by the gill-infesting monogenean Allobivagina sp. (Microcotylea) caused mass mortalities in juveniles of Siganus luridus cultured in seawater earthen ponds and holding tanks in Eilat (Gulf of Aqaba, Red Sea). Other species of Siganus and adults of S. luridus cultured in the same systems acquired a low intensity of infestation. Most hyperinfected fish were emaciated and anaemic with hematocrit values below 10 %. Skin and mouth infestations by the monogenean Benedenia monticelli (Capsaloidea) caused mass mortalities in grey mullets (Mugilidae). These mortalities occurred in large individuals in wild populations of Liza carinata from lagoonal habitats in the Gulf of Suez and in most species of grey mullets cultured in Eilat. The intensity of infestation correlated positively with severity of infestation, and the common sites of infestation corresponded with areas of severe pathological alterations. Spontaneous recovery followed the climax of an epizootic, both for infested S. luridus and infested grey mullets. Decline in infestation coincided with remission of the pathological signs.

Aboveground insect infestation attenuates belowground Agrobacterium-mediated genetic transformation.

Science.gov (United States)

Song, Geun Cheol; Lee, Soohyun; Hong, Jaehwa; Choi, Hye Kyung; Hong, Gun Hyong; Bae, Dong-Won; Mysore, Kirankumar S; Park, Yong-Soon; Ryu, Choong-Min

2015-07-01

Agrobacterium tumefaciens causes crown gall disease. Although Agrobacterium can be popularly used for genetic engineering, the influence of aboveground insect infestation on Agrobacterium induced gall formation has not been investigated. Nicotiana benthamiana leaves were exposed to a sucking insect (whitefly) infestation and benzothiadiazole (BTH) for 7 d, and these exposed plants were inoculated with a tumorigenic Agrobacterium strain. We evaluated, both in planta and in vitro, how whitefly infestation affects crown gall disease. Whitefly-infested plants exhibited at least a two-fold reduction in gall formation on both stem and crown root. Silencing of isochorismate synthase 1 (ICS1), required for salicylic acid (SA) synthesis, compromised gall formation indicating an involvement of SA in whitefly-derived plant defence against Agrobacterium. Endogenous SA content was augmented in whitefly-infested plants upon Agrobacterium inoculation. In addition, SA concentration was three times higher in root exudates from whitefly-infested plants. As a consequence, Agrobacterium-mediated transformation of roots of whitefly-infested plants was clearly inhibited when compared to control plants. These results suggest that aboveground whitefly infestation elicits systemic defence responses throughout the plant. Our findings provide new insights into insect-mediated leaf-root intra-communication and a framework to understand interactions between three organisms: whitefly, N. benthamiana and Agrobacterium. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Is Reduction in Yield Potential of Some Brassicaceous Species Due to Aphid Infestation Associated with the Changes in Stomatal Factors of Photosynthesis

International Nuclear Information System (INIS)

Razaq, M.; Farooq, M.; Abbas, G.; Rehman, H. M.; Iqbal, M.

2016-01-01

Aphids cause heavy yield losses to Brassicaceous species by affecting various physiological and biochemical processes including photosynthesis. In the present study, seasonal activity of aphid population and its impact on some brassicaceous species was assessed. Three brassicaceous species (Brassica campestris, Brassica carinata, Eruca sativa) were grown in field following standard agricultural practices. Plants of control plots retained aphid free by insecticide spray, whereas treatment plots were freely allowed for aphid infestation. There was also intermediate treatment of partial aphid infestation where insecticidal spray was applied two times. Peak populations of both aphid species were observed in the 2nd week of March during which plant photosynthetic attributes were recorded. At the time of maturity, yield attributes were also recorded. From the results, it is obvious that application of insecticide significantly reduced the aphid populations on the three brassicaceous species and enhanced the crop yield. Yield losses due to aphid infestation were maximal in Brassica campestris followed by B. carinata whereas it was minimal in Eruca sativa. Yield losses in Brassica campestris and B. carinata were due to reduction in number of pods per plant, number of seeds per pod and size of seeds, whereas yield losses due to aphid infestation in Eruca sativa was mainly attributed to reduction in number of pods per plant. Although insecticidal spray reduced the aphid population and increased growth and productivity of all brassicaceous species, it did not change photosynthetic capacity of all plants except in Eruca sativa. Moreover, growth and yield reduction was not associated with stomatal factors of photosynthesis. Chlorophyll contents measured as SPAD values were reduced due to aphid infestation which is positively associated with yield reduction. Insecticidal spray increased chlorophyll contents in these three brassicaceous species by reducing aphid population

Artificial infestation of Boophilus microplus in beef cattle heifers of four genetic groups

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Ana Mary da Silva

2007-01-01

Full Text Available Resistance of beef cattle heifers to the cattle tick Boophilus microplus was evaluated by artificial infestation of 66 beef cattle heifers of the following genetic groups: 16 Nelore (NE, 18 Canchim x Nelore (CN, 16 Angus x Nelore (AN and 16 Simmental x Nelore (SN. The animals, with a mean age of 16.5 months, were maintained with no chemical tick control in a Brachiaria decumbens pasture. Four artificial infestations with 20,000 B. microplus larvae were carried out 14 days apart and from day 18 to day 22 of each infestation the number of engorged female ticks (> 4.5 mm was counted on the left side of each heifer. Data were analyzed as the percentage of return (PR = percentage of ticks counted relative to the number infested, transformed to (PR¼, and as log10 (Cij + 1, in which Cij is the number of ticks in each infestation, using the least squares method with a model that included the effects of genetic group (GG, animal within GG (error a, infestation number (I, GG x I and the residual (error b. Results indicated a significant GG x I interaction, because AN and SN heifers had a higher percentage of return than CN and NE heifers, while CN heifers showed a higher percentage of return than the NE heifers only in infestations 3 and 4. Transformed percentages of return were NE = 0.35 ± 0.06, AN = 0.89 ± 0.06, CN = 0.54 ± 0.05 and SN = 0.85 ± 0.06.

Rat infestation associated with environmental deficiencies in an urban slum community with high risk of leptospirosis transmission.

Science.gov (United States)

Santos, Norlan de Jesus; Sousa, Erica; Reis, Mitermayer G; Ko, Albert I; Costa, Federico

2017-03-09

We analyzed environmental factors that provide food, water and harborage to rodents and the risk of household rodent infestation in a slum community with a high risk of leptospirosis transmission. Detailed environmental surveys were performed in 221 households. Multivariate regression models evaluated the association between rodent infestation and socioeconomic status and environmental attributes obtained from Geographical Information System surveys. The general household infestation rate was 45.9%. Rattus norvegicus signs were the most prevalent, present in 74% of the infested households. The risk for rodent infestation was associated with environmental factors supporting harborage for rats, such as dilapidated fences/walls (OR: 8.95; 95%CI: 2.42-33.12) and households built on an earthen slope (OR: 4.68; 95%CI: 2.23-9.81). An increase of 1 meter from the nearest sewer was associated with a 3% (95%CI: 1%-5%) decrease in the risk of rodent infestation. A lack of sanitation where poor people live provides factors for rat infestation and could the target of educational interventions.

Relative importance of meteorological and geographical factors in the distribution of Fasciola hepatica infestation in farmed sheep in Qinghai province, China

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Qin Hongyu

2016-01-01

Full Text Available Fasciola hepatica is an important trematode parasite of economic importance that infests sheep and cattle worldwide. We conducted a detailed investigation into the spatial distribution of F. hepatica infestation in farmed sheep in Qinghai (Wutumeiren province, Mainland China. Mathematical modelling was used to assess the inter-relationships between meteorological and geographical factors and the risk of F. hepatica infestation across the province. A capture enzyme-linked immunosorbent assay (ELISA test (MM3-SERO was used to detect F. hepatica infestation. A niche model based on the maximum entropy method (MaxEnt was used to estimate the influence of meteorological and geographical factors on the observed spatial distribution of F. hepatica infestation. Results of jackknife analysis indicated that temperature, precipitation, solar radiation, digital elevation and slope were associated with the occurrence of F. hepatica infestation, and that infestation rates were significantly higher among animals from districts with a high percentage of grassland habitat. The findings indicate that meteorological and geographical factors may be important variables affecting the distribution of F. hepatica infestation and should be taken into account in the development of future surveillance and control programmes for fascioliasis.

Flea (Pulex simulans) infestation in captive giant anteaters (Myrmecophaga tridactyla).

Science.gov (United States)

Mutlow, Adrian G; Dryden, Michael W; Payne, Patricia A

2006-09-01

A pair of captive adult giant anteaters (Myrmecophaga tridactyla) presented heavily infested with a flea species (Pulex simulans) commonly found on Virginia opossums (Didelphis virginiana) and raccoons (Procyon lotor) in the central United States. In this case, the flea was demonstrated to have completed its entire life cycle with the anteaters as the host. A single treatment of topical imidacloprid, coupled with removal and replacement of infested bedding, was rapidly effective at controlling the infestation and no adverse effects of the drug were noted. Control of the anteater infestation also removed the flea infestation of aardvarks in the same building.

Spatio-temporal distribution of the infestations of ...

African Journals Online (AJOL)

Spatial distribution of the infestations revealed experimental plots having recorded between 0 and 8 ... Infestations were also independent of abiotic factors (rainfall, temperature and ... chemical fight, by terrestrial way, air or systemic, ... the implementation of efficient fight plan strategy. ..... Influence of abiotic factors on the.

Aboveground Whitefly Infestation-Mediated Reshaping of the Root Microbiota.

Science.gov (United States)

Kong, Hyun G; Kim, Byung K; Song, Geun C; Lee, Soohyun; Ryu, Choong-Min

2016-01-01

Plants respond to various types of herbivore and pathogen attack using well-developed defensive machinery designed for self-protection. Infestation from phloem-sucking insects such as whitefly and aphid on plant leaves was previously shown to influence both the saprophytic and pathogenic bacterial community in the plant rhizosphere. However, the modulation of the root microbial community by plants following insect infestation has been largely unexplored. Only limited studies of culture-dependent bacterial diversity caused by whitefly and aphid have been conducted. In this study, to obtain a complete picture of the belowground microbiome community, we performed high-speed and high-throughput next-generation sequencing. We sampled the rhizosphere soils of pepper seedlings at 0, 1, and 2 weeks after whitefly infestation versus the water control. We amplified a partial 16S ribosomal RNA gene (V1-V3 region) by polymerase chain reaction with specific primers. Our analysis revealed that whitefly infestation reshaped the overall microbiota structure compared to that of the control rhizosphere, even after 1 week of infestation. Examination of the relative abundance distributions of microbes demonstrated that whitefly infestation shifted the proteobacterial groups at week 2. Intriguingly, the population of Pseudomonadales of the class Gammaproteobacteria significantly increased after 2 weeks of whitefly infestation, and the fluorescent Pseudomonas spp. recruited to the rhizosphere were confirmed to exhibit insect-killing capacity. Additionally, three taxa, including Caulobacteraceae, Enterobacteriaceae, and Flavobacteriaceae, and three genera, including Achromobacter, Janthinobacterium, and Stenotrophomonas, were the most abundant bacterial groups in the whitefly infested plant rhizosphere. Our results indicate that whitefly infestation leads to the recruitment of specific groups of rhizosphere bacteria by the plant, which confer beneficial traits to the host plant. This

Aboveground Whitefly Infestation-mediated Reshaping of the Root Microbiota

Directory of Open Access Journals (Sweden)

Hyun Gi Kong

2016-09-01

Full Text Available Plants respond to various types of herbivore and pathogen attack using well-developed defensive machinery designed for self-protection. The phloem-sucking insect infestation such as whitefly and aphid on plant leaves were previously shown to influence both the saprophytic and pathogenic bacterial community in the plant rhizosphere. However, the modulation of the root microbial community by plants following insect infestation has been largely unexplored. Only limited studies of culture-dependent bacterial diversity caused by whitefly and aphid have been conducted. In this study, to obtain a complete picture of the belowground microbiome community, we performed high-speed and high-throughput next-generation sequencing. We sampled the rhizosphere soils of pepper seedlings at 0, 1, and 2 weeks after whitefly infestation versus the water control. We amplified a partial 16S ribosomal RNA gene (V1–V3 region by polymerase chain reaction with specific primers. Our analysis revealed that whitefly infestation reshaped the overall microbiota structure compared to that of the control rhizosphere, even after 1 week of infestation. Examination of the relative abundance distributions of microbes demonstrated that whitefly infestation shifted the proteobacterial groups at week 2. Intriguingly, the population of Pseudomonadales of the class Gammaproteobacteria significantly increased after 2 weeks of whitefly infestation and confirmed the recruitment of fluorescent Pseudomonas spp. exhibiting the insect-killing capacity. Additionally, three taxa, including Caulobacteraceae, Enterobacteriaceae, and Flavobacteriaceae, and three genera, including Achromobacter, Janthinobacterium, and Stenotrophomonas, were the most abundant bacterial groups in the whitefly-infested plant rhizosphere. Our results indicate that whitefly infestation leads plant recruiting specific group of rhizosphere bacteria conferring beneficial traits for host plant. This study provides a new

Resistance and tolerance to the brown planthopper, Nilaparvata lugens (Stål), in rice infested at different growth stages across a gradient of nitrogen applications.

Science.gov (United States)

Horgan, Finbarr G; Peñalver Cruz, Ainara; Bernal, Carmencita C; Ramal, Angelee Fame; Almazan, Maria Liberty P; Wilby, Andrew

2018-03-01

High resource availability can reduce anti-herbivore resistance (a plant's ability to defend against herbivores and reduce damage) in rice, Oryza sativa L, but may also increase tolerance (a plant's ability to withstand damage by, for example, compensatory growth). Through a series of greenhouse, screenhouse and field experiments, this study examines fitness (survival and development × reproduction) of the brown planthopper, Nilaparvata lugens (Stål), on resistant (IR62) and susceptible (IR22) rice varieties and age-related rice tolerance to planthopper damage under varying resource (nitrogenous fertilizer) availability. Planthoppers reared on IR62 in the greenhouse had lower fitness than planthoppers on IR22. IR62 became increasingly resistant as plants aged. IR22 was generally more tolerant of planthopper damage, and tolerance increased in IR22, but declined in IR62, as the plants aged. Rice plants infested at pre-tillering stages (3-4 leaf stage) in the screenhouse had greater losses to root, shoot and grain yield per unit weight of planthopper than plants infested at tillering stages, particularly in IR22. These trends were mainly due to the impact of planthoppers during pre-tillering stages and the length of exposure to the planthoppers. High nitrogen compromised IR62 resistance, particularly in tillering plants in the greenhouse study; however, high nitrogen did not increase planthopper biomass-density on IR62 in greenhouse or field cages. Tolerance to damage in IR62 at mid-tillering stages declined under increasing levels of nitrogen, but nitrogen increased tolerance during late-tillering stages. Planthopper damage to IR22 in field cages was severe and hopperburn (plant death) occurred in 83% of IR22 plants under high nitrogen (60-150 kg N ha -1 ). In contrast, despite planthopper infestations, damage to IR62 was low in field-grown plants and productivity (tillers, roots, shoots and grain) increased in IR62 under increasing nitrogen. Our results

Using dendrochronology to model hemlock woolly adelgid effects on eastern hemlock growth and vulnerability

Science.gov (United States)

James Rentch; Mary Ann Fajvan; Richard Evans; Brad. Onken

2008-01-01

This study examined the relationship between eastern hemlock (Tsuga canadensis (L.) Carr.) crown condition and changes in radial growth associated with infestation by hemlock woolly adelgid (HWA), Adelges tsugae (Hemiptera: Adelgidae). Tree-ring chronologies of eastern hemlock were used to develop a binomial decline index based on...

Impacts of human-related practices on Ommatissus lybicus infestations of date palm in Oman.

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Khalifa M Al-Kindi

Full Text Available Date palm cultivation is economically important in the Sultanate of Oman, with significant financial investments coming from both the government and private individuals. However, a widespread Dubas bug (DB (Ommatissus lybicus Bergevin infestation has impacted regions including the Middle East, North Africa, Southeast Russia, and Spain, resulting in widespread damages to date palms. In this study, techniques in spatial statistics including ordinary least squares (OLS, geographically weighted regression (GRW, and exploratory regression (ER were applied to (a model the correlation between DB infestations and human-related practices that include irrigation methods, row spacing, palm tree density, and management of undercover and intercropped vegetation, and (b predict the locations of future DB infestations in northern Oman. Firstly, we extracted row spacing and palm tree density information from remote sensed satellite images. Secondly, we collected data on irrigation practices and management by using a simple questionnaire, augmented with spatial data. Thirdly, we conducted our statistical analyses using all possible combinations of values over a given set of candidate variables using the chosen predictive modelling and regression techniques. Lastly, we identified the combination of human-related practices that are most conducive to the survival and spread of DB. Our results show that there was a strong correlation between DB infestations and several human-related practices parameters (R2 = 0.70. Variables including palm tree density, spacing between trees (less than 5 x 5 m, insecticide application, date palm and farm service (pruning, dethroning, remove weeds, and thinning, irrigation systems, offshoots removal, fertilisation and labour (non-educated issues, were all found to significantly influence the degree of DB infestations. This study is expected to help reduce the extent and cost of aerial and ground sprayings, while facilitating the

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

Science.gov (United States)

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

2013-10-01

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

Rootstock effects on pistachio trees grown in Verticillium dahliae-infested soil

OpenAIRE

Epstein, Lynn; Beede, R; Kaur, S; Ferguson, L

2004-01-01

In a field trial in soil infested with Verticillium dahliae, we compared the yield, growth, incidence of symptoms of Verticillium wilt, and mortality of two interspecific hybrid pistachio tree rootstocks (UCBI and PGII) with the standard rootstocks: the V dahliae-resistant and susceptible Pistacia integerrima and P. atlantica, respectively. After 10 years, the trees were destructively sampled for V dahliae in the xylem at the graft union. The results indicate that trees on the (P. atlantica '...

Ticks infesting bats (Mammalia: Chiroptera) in the Brazilian Pantanal.

Science.gov (United States)

Muñoz-Leal, Sebastián; Eriksson, Alan; Santos, Carolina Ferreira; Fischer, Erich; de Almeida, Juliana Cardoso; Luz, Hermes R; Labruna, Marcelo B

2016-05-01

Ticks associated with bats have been poorly documented in the Neotropical Zoogeographical Region. In this study, a total of 1028 bats were sampled for tick infestations in the southern portion of the Brazilian Pantanal. A total of 368 ticks, morphologically identified as Ornithodoros hasei (n = 364) and O. mimon (n = 4), were collected from the following bat species: Artibeus planirostris, Platyrrhinus lineatus, Phyllostomus hastatus, Mimon crenulatum and Noctilio albiventris. Morphological identification of O. hasei was confirmed by molecular analysis. Regarding the most abundant bat species, only 40 (6.2%) out of 650 A. planirostris were infested by O. hasei, with a mean intensity of 7.2 ticks per infested bat, or a mean abundance of 0.44 ticks per sampled bat. Noteworthy, one single P. hastatus was infested by 55 O. hasei larvae, in contrast to the 2.5-7.2 range of mean intensity values for the whole study. As a complement to the present study, a total of 8 museum bat specimens (6 Noctilio albiventris and 2 N. leporinus), collected in the northern region of Pantanal, were examined for tick infestations. These bats contained 176 ticks, which were all morphologically identified as O. hasei larvae. Mean intensity of infestation was 22, with a range of 1-46 ticks per infested bat. Our results suggest that A. planirostris might play an important role in the natural life cycle of O. hasei in the Pantanal.

Application of Laser Induced Breakdown Spectroscopy in Early Detection of Red Palm Weevil: (Rhynchophorus ferrugineus) Infestation in Date Palm

International Nuclear Information System (INIS)

Farooq, W. A.; Tawfik, Walid; Rasool, K. G.; Aldawood, A. S.

2015-01-01

The Kingdom of Saudi Arabia is one of the leading date producing countries. Unfortunately, this important fruit crop is under great threat from the red palm weevil (RPW) (Rhynchophorus ferrugineus), which is a highly invasive pest. Several techniques, including visual inspection, acoustic sensors, sniffer dogs, and pheromone traps have been tried to detect the early stages of a RPW infestation; however, each method has suffered certain logistical and implementation issues. We have applied laser induced breakdown spectroscopy (LIBS) for the early detection of RPW infestation. Through the analysis of the observed LIBS spectra of different infested and healthy samples, we have found presence of Ca, Mg, Na, C, K elements and OH, CN molecules. The spectra also reveal that with the population growth of the pest, the intensity of Mg and Ca atomic lines in LIBS spectra increases rapidly. Similar behavior is observed in the molecular lines of LIBS spectra. The obtained results indicate that the LIBS technique can be used for the early detection of RPW infestation without damaging the date palms. (paper)

Application of Laser Induced Breakdown Spectroscopy in Early Detection of Red Palm Weevil: (Rhynchophorus ferrugineus) Infestation in Date Palm

Science.gov (United States)

A. Farooq, W.; G. Rasool, K.; Walid, Tawfik; S. Aldawood, A.

2015-11-01

The Kingdom of Saudi Arabia is one of the leading date producing countries. Unfortunately, this important fruit crop is under great threat from the red palm weevil (RPW) (Rhynchophorus ferrugineus), which is a highly invasive pest. Several techniques, including visual inspection, acoustic sensors, sniffer dogs, and pheromone traps have been tried to detect the early stages of a RPW infestation; however, each method has suffered certain logistical and implementation issues. We have applied laser induced breakdown spectroscopy (LIBS) for the early detection of RPW infestation. Through the analysis of the observed LIBS spectra of different infested and healthy samples, we have found presence of Ca, Mg, Na, C, K elements and OH, CN molecules. The spectra also reveal that with the population growth of the pest, the intensity of Mg and Ca atomic lines in LIBS spectra increases rapidly. Similar behavior is observed in the molecular lines of LIBS spectra. The obtained results indicate that the LIBS technique can be used for the early detection of RPW infestation without damaging the date palms.

Strongyloides stercoralis infestation in HIV seropositive patients in ...

African Journals Online (AJOL)

Background: A contemporary surge in diarrhoeal illnesses due to parasitic infestations is believed to be a synergy between endemicity and HIV seropositivity. Aim: To determine the prevalence of Strongyloides stercoralis infestation among HIV seropositive patients at the University of Port Harcourt Teaching Hospital.

Influence of simultaneous infestations of Prostephanus truncatus ...

African Journals Online (AJOL)

The specific objective was to determine the number of the insect pests at F1 and F2 and the grain weight losses caused by the simultaneous pests\\' infestations of shelled maize in the search for a control strategy. The results showed a change in adult insect numbers from F1 to F2. During single infestation the change in P.

some nutritional aspects of haemonchosis in experimentally infested ...

African Journals Online (AJOL)

nutritional aberration has been described as anorexia in both pure (Evans, Blunt & Southcott, 1963) and mixed infestations where Haemonchus contortus was prominent. (Clark, Ortlepp, Bosman, Laurence, Groenewald & Quin,. 1951; Shumard et al. 1957). Further observations on nutritional aspects of a pure infestation of ...

Intestinal Worm Infestation and Anaemia in Pregnant Women

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Krishna Bahadur Raut

2016-03-01

Conclusions: Aanaemia is prevalent in pregnant women of PHCRC, chapagaun and there was a significant correlation between anaemia and worm infestation. However, the relation among the haemoglobin level, iron, folic acid and albendazole was not significant. Keywords: anaemia; infestation; pregnant women; worm. | PubMed

Prevalence of bovine trypanosomosis and assessment of trypanocidal drug resistance in tsetse infested and non-tsetse infested areas of Northwest Ethiopia

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Shimelis Dagnachew

2017-05-01

Full Text Available The Northwestern region of Ethiopia is affected by both tsetse and non-tsetse transmitted trypanosomosis with a significant impact on livestock productivity. The control of trypanosomosis in Ethiopia relies on either curative or prophylactic treatment of animals with diminazene aceturate (DA or isometamidium chloride (ISM. In the present work; questionnaire survey, cross-sectional and experimental studies were carried out to; a assess the utilization of trypanocidal drugs; b determine the prevalence of bovine trypanosomosis and; c assess the drug resistant problems respectively in Tsetse and non-tsetse infested areas on NW Ethiopia. A total of 100 respondents were included for the survey and the questionnaires focused on the drug utilization practices for the control of Trypanosomosis. Blood from cattle 640 (324 cattle tested in 2011, 316 cattle tested in 2012 and 795 (390 cattle tested in 2011, 405 cattle tested in 2012 were examined from tsetse infested and non-tsetse infested areas respectively using the buffy coat technique and thin blood smear for the detection of trypanosomes and measurement of packed cell volume (PCV. For the assessment of trypanocidal drug resistance three isolates, one from tsetse (TT and two from non-tsetse (NT areas were used on thirty six trypanosome naïve calves. The experimental animals were divided randomly into six groups of six animals (TT-ETBS2-DA, TT-ETBS2-ISM, NT-ETBD2-DA, NT-ETBD2-ISM, NT-ETBD3-DA and NT-ETBD3-ISM, which were infected with T. vivax isolated from a tsetse-infested or non-tsetse infested area with 2 × 106 trypanosomes from donor animals, and in each case treated with higher dose of DA or ISM. The results of the questionnaire survey showed trypanosomosis was a significant animal health constraint for 84% and 100% of the farmers questioned in non-tsetse and tsetse infested areas of Northwest Ethiopia respectively. Responses on trypanocidal drug utilization practices indicated that risk

Diagnosing the influence of model structure on the simulation of water, energy and carbon fluxes on bark beetle infested forests

Science.gov (United States)

Gochis, D. J.; Gutmann, E. D.; Brooks, P. D.; Reed, D. E.; Ewers, B. E.; Pendall, E.; Biederman, J. A.; Harpold, A. A.; Barnard, H. R.; Hu, J.

2011-12-01

Forest dynamics induced by insect infestation can have a significant, local impact on plant physiological regulation of water, energy and carbon fluxes. Rapid mortality succeeded by more gradually varying land cover changes are presently thought to initiate a cascade of changes to water, energy and carbon budgets at the forest stand scale. Initial model sensitivity results have suggested very strong changes in land-atmosphere exchanges of these variables. Specifically, model results from the Noah land surface model, a relatively simple model, have suggested that loss of transpiration function may result in a nearly 50% increase in seasonal soil moisture values and similar increases in runoff production for locations in the central Rocky Mountains. However, differing model structures, such as the representation of plant canopy architecture, snowpack dynamics, dynamic vegetation and hillslope hydrologic processes, may significantly confound the synthesis of results from different modeling systems. We assess the performance of new suite of model simulations from three different land surface models of differing model structures and complexity levels against a comprehensive set of field observations of land surface flux and state variables. The focus of the analysis is in diagnosing how model structure influences changes in energy, water and carbon budget partitioning prior to and following insect infestation. Specific emphasis in this presentation is placed on verifying variables that characterize top of canopy and within canopy energy and water fluxes. We conclude the presentation with a set of recommendations about the advantages and disadvantages of various model structures in their simulation of insect driven forest dynamics.

Growth and yield of grafted cucumbers in soil infested with root-knot nematodes

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Smiljana Goreta Ban

2014-03-01

Full Text Available The aim of this study was to determine the effect of rootstocks on the growth and yield of cucumber (Cucumis sativus L. plants in soils infested with root-knot nematodes (Meloidogyne spp. Cucumber 'Adrian' was grown with its own roots or was grafted onto three rootstocks of Lagenariasiceraria (Molina Standi. ('Emphasis', 'S-1', and 'Gourd', two interspecific hybrid rootstocks of Cucurbita maxima Duchesne x C. moschata Duchesne ('Strong Tosa' and 'RS 841 Improved' and zucchini Cucurbita pepo L. ('Romanesco Zucchini'. The experiments were conducted in commercial greenhouse, with cucumber grafted onto three rootstocks in the first season and onto six rootstocks in the second spring-summer season. The number of leaves was considerably affected by the rootstock in both seasons, and was the highest for the plants grafted onto interspecific rootstocks (28.0 in the first and 44.9 in the second season. The plants grafted onto 'Strong Tosa' had higher total number of fruits (19.9 and yield (5.38 kg compared to other rootstocks or non-grafted plants in first season, and the same result was found for two interspecific rootstocks in the second season (6.96 kg and more than 28.9 fruits per plant. The total soluble solids, pH and electrical conductivity of the fruit were not affected by rootstock, while titratable acidity changed with the rootstock type. The grafting of cucumber plants onto different rootstocks was confirmed as an acceptable non-chemical method to compete with the limitations of soils infected with root-knot nematodes, but the effect was highly dependent on the choice of the rootstock.

Infestation of the banana root borer among different banana plant genotypes

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Fernando Teixeira de Oliveira

Full Text Available ABSTRACT: In this study, we aimed to investigate Cosmopolites sordidus (Coleoptera: Dryophthoridae infestation among different banana genotypes in a commercial banana orchard over the course of 30 months. Banana root borer infestation was compared in 20 banana genotypes, including five varieties and 15 hybrids. Overall, we observed that 94.17% of pest infestation cases occurred in the cortex region, and only 5.83% occurred in the central cylinder. Genotypes least sensitive to infestation were the Prata Anã (AAB and Pacovan (AAB varieties, where no damage was recorded. Among the hybrid genotypes, PV 9401 and BRS Fhia 18 showed intermediate levels of sensitivity, while BRS Tropical hybrids (AAAB, PA 9401 (AAAB, BRS Vitoria (AAAB, YB 4203 (AAAB, and Bucaneiro (AAAA were the most sensitive to attack by banana root borer. This study demonstrated that the infestation of the banana root borer varies according banana plant genotype, and the utilization of less susceptible genotypes could reduce infestation rates of C. sordidus.

EFFECTS OF INSECT PEST INFESTATION ON THE CAFFEINE ...

African Journals Online (AJOL)

The caffeine content of nuts of Cola nitida and C. acuminata infested by insect pests in four major geographical zones of Nigeria have been determined and compared with the uninfested ones using high-performance liquid chromatography (HPLC). The findings showed that the infestation has no significant effect on the ...

Occurrence and biology of goat warble fly infestation by Przhevalskiana silenus (Diptera, Oestridae) in Iran.

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Oryan, A; Razavi, S M; Bahrami, S

2009-12-03

Goat warble fly infestation (GWFI) by the larvae of Przhevalskiana silenus is endemic in goats of semi-hilly and mountainous regions of Iran. This myiasis has severe economic impact on tanning industries, and it is responsible for impaired milk and meat production, growth retardation and carcass depreciation. To estimate the prevalence of GWFI in the southern areas of Iran, from October 2006 to December 2008, the carcasses of 8000 goats at a Shiraz slaughterhouse and 1000 each at Marvdasht and Darab cities were examined weekly for the presence of P. silenus larvae. In addition, appropriate sections from the skin and subcutaneous tissues were processed for histopathological investigation. The prevalence rate of infestation in different cities varied from 7.0% to 18.9% and the minimum and maximum infestation rate was 3 and 78, with an average rate of infestation of 26.2 warbles per animal. Significant differences were observed in the prevalence among different age groups with no significant difference between male and female animals. First instar larvae (L(1)) were found on infected animals from early August to end of September, second larval stage (L(2)) from early October to end of November and third-stage larvae (L(3)) from early December to mid-March. No larvae were found on skin or subcutaneous tissues from end of March to late July. Live L(1) initiated mild lymphocyte, macrophage and eosinophil infiltration while dead L(1) initiated granulomatous or pyogranulomatous reactions. Live L(2) induced severe inflammatory reaction and massive tissue necrosis, which continued for L(3) and until the end of infestation phase. The subcutaneous tissues, dermis and epidermis became necrotic and fragmented, and L(3) penetrated the necrotic area to start its aerobic life cycle.

A Community-Based Surveillance on Determinants of Rodent Infestation

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Hsiu-Hua Pai

2003-01-01

Full Text Available Rodent infestation is an important factor in the transmission of infectious diseases of public health importance. From October to November 1998, surveillance stations were established in 110 boroughs of Kaohsiung City in southern Taiwan. Boroughs were chosen by random sampling 10 boroughs from each of 11 districts (464 boroughs in the city. The extent of rodent infestation was determined by cage trapping. The possibility of applying a community-based control program was evaluated by investigating associated demographic and environmental factors as well as related knowledge, attitudes, and behaviors. A total of 90 rodents were trapped in 41% of the 110 boroughs. Using univariate analyses, 17 factors were significantly associated with rodent infestation. A lack of knowledge that rodent control relies on community cooperation was the most important factor among the seven variables associated with the extent of rodent infestation (OR 3.1 by logistic multiple regression. This revealed the importance of community cooperation in controlling rodent infestation. Moreover, improvement of environmental hygiene associated with garbage problems, such as cleanliness of storage rooms and closets, and the hygiene of empty space and resource recycling stations should not be ignored.

Reaction of the mussel Mytilus galloprovincialis (Bivalvia) to Eugymnanthea inquilina (Cnidaria) and Urastoma cyprinae (Turbellaria) concurrent infestation.

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Mladineo, Ivona; Petrić, Mirela; Hrabar, Jerko; Bočina, Ivana; Peharda, Melita

2012-05-01

In total 480 individuals of Mytilus galloprovincialis were sampled monthly from October 2009 to September 2010, at the shellfish farm in the Mali Ston Bay, south Adriatic Sea (Croatia) in order to assess the extent of pathology imposed by two parasites, Eugymnanthea inquilina (Cnidaria) and Urastoma cyprinae (Turbellaria). Although a deteriorating impact on host reproduction or condition index was lacking, we evidenced ultrastructural and functional alteration in host cells at the attachment site. Ultrastructural changes included hemocytic encapsulation of the turbellarian and cell desquamation in medusoid infestation. Caspase positive reaction inferred by immunohistochemistry (IHC) was triggered in cases of turbellarian infestation, in contrast with hydroids, suggesting that the former exhibits more complex host-parasite interaction, reflected in the persistent attempts of the parasite to survive bivalve reaction. We have evidenced that both organisms trigger specific host reaction that although not costly in terms of host reproductive cycle or growth, results in mild tissue destruction and hemocyte activation. A lower degree of tissue reaction was observed in cases of hydroid infestation, compared to turbellarian. Copyright © 2012 Elsevier Inc. All rights reserved.

Influence of grooming on Rhipicephalus microplus tick infestation and serum cortisol rates

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Fernanda Ferreira Pessoa

2012-12-01

Full Text Available Grooming is an important factor on animal resistance to ticks. Rhipicephalus microplus is the most pathogenic cattle tick in Brazil causing death in susceptible animals. Cortisol is the hormone of stress. The influence of grooming on tick infestation and serum cortisol level was studied in 16 Holstein heifers from fifth to eight-month-old. They were infested with 10,000 larvae in June/20/2011. Half of them used a necklace made of wood strips and had an infestation chamber made by cotton cloth covering about 50 cm diameter of the shaved flank, fixed at the skin in both sides with adhesive to prevent larvae to escape from the infestation chamber and the amount of larvae was divided into the two chambers. Such artifacts had the purpose to avoid grooming. The heifers remained all the tick parasitic life cycle in individual pens inside a closed shed at Instituto de Zootecnia, in Nova Odessa, São Paulo State. Tick females bigger than 4.5 mm were counted in the right side from day 20 to 22 after the artificial infestation. The tick recovery rate was calculated by adding and multiplying by two the number of ticks counted, assuming that 5,000 female larvae had infested the cattle. Immediately before infestation (day 0 and in day2, day8, and day17 after infestation, blood samples were collected using vacuum tubes, in the morning (8:30 – 10:00 A.M.. Cortisol was measured by immunoassay (EIA and the D.O. (optical density at 420 nm was converted in ng of cortisol/mL of serum sample. The experimental design was randomized with 8 replications. Data from serum cortisol were analyzed using the General linear models of the SPSS® statistical package (version 12.0 using the presence of the artifacts (necklace and chamber and sampling day as independent variables and serum cortisol as the dependent variable. In the analyse of tick recovery rate, the presence of artifacts was the independent variable and tick recovery rate the dependent variable. The presence of

Different clinical allergological features of Taenia solium infestation.

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Minciullo, Paola Lucia; Cascio, Antonio; Isola, Stefania; Gangemi, Sebastiano

2016-01-01

The tapeworm Taenia ( T. ) solium can be responsible for two different conditions: taeniasis and cysticercosis. Helminth infections in human host cause an immune response associated with elevated levels of IgE, tissue eosinophilia and mastocytosis, and with the presence of CD4+ T cells that preferentially produce IL-4, IL-5, and IL-13. Individuals exposed to helminth infections may have allergic inflammatory responses to parasites and parasite antigens. PubMed search of human cases of allergic reactions occurring during T. solium infestation was performed combining the terms (allergy, urticaria, angioedema, asthma, anaphylaxis) with T. solium . A study was considered eligible for inclusion in the review if it reported data on patients with T. solium infestation who had signs or symptoms of allergy. In literature we found six articles reporting the association between an allergic reaction and T. solium infestation: two cases of urticaria, two cases of relapsing angioedema, one case of asthma and two cases of anaphylaxis. Despite the large diffusion of T. solium infestation, we found only a few cases of concomitant allergic reaction and the presence of Taenia in the host. The association between T. solium infestation and allergic manifestations has never been clearly demonstrated, and in absence of a well-documented causality the hypotheses are merely speculative. Therefore, the association between Taenia infection and allergy needs to be thoroughly studied to better clarify if this association may really exist and which is the pathogenetic mechanism supported.

A comparative study on infestation of three varieties of maize ( Zea ...

African Journals Online (AJOL)

A study was carried out to study the infestation of three maize varieties (Maize suwan I–Y, Maize T2 USR – White single cross and Maize suwan 123) by Sitophilus zeamais Motsch. Infestation was assessed by counting the numbers of alive and dead adults and the number of infested and uninfested seeds. It was found out ...

Treatment and control of Trixacarus caviae infestation in a conventional guinea pig (Cavia porcellus) breeding colony.

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Nath, Anjan Jyoti

2016-12-01

A case of sarcoptic mange caused by Trixacarus caviae in a conventional guinea pig breeding colony is reported. The infestation was reported in a large colony of guinea pigs during the month of July, 2013 affecting 30 breeder guinea pigs. Severely infested animals were treated individually with subcutaneous injection of ivermectin 1 % w/v (Neomec ® ) at the rate of 400 µg/kg body weight 10 days apart. Three doses of ivermectin were sufficient to eliminate the parasite which tested negative after 30 days of the first treatment. The entire colony was given preventive dose of ivermectin spray (2 mg/ml solution) following the same schedule. Strict hygienic measures were followed. New hair growth in the severely affected animals was evidenced on 30th day of treatment.

Emerald ash borer infestation rates in Michigan, Ohio, and Indiana.

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Eric L. Smith; Andrew J. Storer; Bryan K. Roosien

2009-01-01

The goal of this study was to obtain an estimate of the infestation rate of ash trees with emerald ash borer (EAB) (Agrilus planipennis, Fairmaire; Coleoptera; Buprestidae), across its primary infestation zone of...

Sarcoptic mange infestation in rabbits in an organized farm at Tamil Nadu.

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Arul Prakash, M; Soundararajan, C; Nagarajan, K; Tensingh Gnanaraj, P; Ramesh Saravanakumar, V

2017-06-01

Sarcoptes scabiei are burrowing mites which causes major constraints in rabbit production. Eighty-eight rabbits were examined for mange infestation at University Research Farm, Tamil Nadu. Overall incidence of mange infestation in rabbit was 23.6 %. On microscopical examination, the mite was identified as Sacoptes scabiei var cuniculi. Among the breeds, Soviet Chinchilla were found to be infested more (57.14 %) followed by New Zealand White (28.57 %) and White Giant (28.57 %). Among the age groups, adults (33.33 %) were heavily infested than the grower (21.88 %) whereas, suckling had no infestation of mange. Among the sex, males (21.95 %) were heavily infested than the females (14.89 %). Lesions were mostly found on the edges of ear, nose, face and legs and characterized by loss of hair, thickening of the skin, irregular dried dirty encrusted scabs with erythema and disfigurement of face and ear.

Tick infestation on sheep, goat, horse and wild hare in Tamil Nadu.

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Soundararajan, C; Nagarajan, K; Muthukrishnan, S; Arul Prakash, M

2018-03-01

The prevalence of tick infestation and their predilection sites on sheep, goat, horse and wild hare were studied at various places of Tamil Nadu, India. The prevalence of tick infestation in Madras red sheep, Tellicherry goat and horse was 77.11, 78.21 and 13.33%, respectively. Sheep were heavily infested with Haemaphysalis bispinosa followed by Hyalomma isaaci , Rhipicephalus haemaphysaloides and H . anatolicum . The ticks from goats were identified as H . bispinosa , R . haemaphysaloides , H . isaaci and R . sanguineus . Horses were infested with Otobus megnini and R . sanguineus . The ticks on wild hare ( Lepus nigricollis ) were identified as R . haemaphysaloides and H . bispinosa . Wild hare acts as a source of infestation to the sheep and goats since these animals shared the same field.

Field infestation of rambutan fruits by internal-feeding pests in Hawaii.

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McQuate, G T; Follett, P A; Yoshimoto, J M

2000-06-01

More than 47,000 mature fruits of nine different varieties of rambutan (Nephelium lappaceum L.) were harvested from orchards in Hawaii to assess natural levels of infestation by tephritid fruit flies and other internal feeding pests. Additionally, harvested, mature fruits of seven different rambutan varieties were artificially infested with eggs or first-instars of Mediterranean fruit fly, Ceratitis capitata (Wiedemann), or oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) to assess host suitability. When all varieties were combined over two field seasons of sampling, fruit infestation rates were 0.021% for oriental fruit fly, 0.097% for Cryptophlebia spp. (Lepidoptera: Tortricidae), and 0.85% for pyralids (Lepidoptera). Species of Cryptophlebia included both C. illepida (Butler), the native Hawaiian species, and C. ombrodelta (Lower), an introduced species from Australia. Cryptophlebia spp. had not previously been known to attack rambutan. The pyralid infestation was mainly attributable to Cryptoblabes gnidiella (Milliere), a species also not previously recorded on rambutan in Hawaii. Overall infestation rate for other moths in the families Blastobasidae, Gracillariidae, Tineidae, and Tortricidae was 0.061%. In artificially infested fruits, both species of fruit fly showed moderately high survivorship for all varieties tested. Because rambutan has such low rates of infestation by oriental fruit fly and Cryptophlebia spp., the two primary internal-feeding regulatory pests of rambutan in Hawaii, it may be amenable to the alternative treatment efficacy approach to postharvest quarantine treatment.

Molecular detection of protozoan parasites in ticks infesting cattle ...

African Journals Online (AJOL)

An assessment of protozoan parasite load in the ticks infesting cattle entering the country by hooves through a major trans-boundary route in Ogun State was carried out using ... This is the first report on protozoan parasites detected in ticks infesting cattle entering Nigeria through a major trans-boundary route in Nigeria.

Infestation caused by acanthocephala

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Daniele Crotti

2009-03-01

Full Text Available An on-line case of infestation caused by M. moniliformis is descripted. This rodents’ worm, belonging to acanthocephala, can be rarely responsible of human intestinal pathology. The case is the pretext for a brief revision on this parasitosis. So, biological, epidemiological, clinical and diagnostical findings are reported.

Increased gum arabic production after infestation of Acacia senegal ...

African Journals Online (AJOL)

Jane

2011-07-20

Jul 20, 2011 ... chemical properties of gum were determined for infested and control trees. A. senegal infested by A. ... also in the textile, pottery, lithography, cosmetics and ... Deforestation within the gum belt has lead to an increase in desert .... Atomic Absorption = V*N EDTA*1000/Volume of extract (mg/l). Where, V is the ...

Intestinal parasitic infestations in children living in Warsaw

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Krzysztof Korzeniewski

2016-06-01

Full Text Available Background. Intestinal parasitic infestations pose one of the biggest health problems of the contemporary world. Objectives. The aim of this article was to present the prevalence of intestinal parasites among children living in a large urban agglomeration. Material and methods . 1823 children (916 girls and 907 boys, aged 3–6, attending 31 different pre-schools in Warsaw, were examined in 2014. Stool specimens were tested in the Department of Epidemiology and Tropical Medicine of the Military Institute of Medicine by light microscopy using three different diagnostic methods (direct smear in Lugol’s solution, decantation with distilled water, Fülleborn’s flotation. The material for testing, fixed in 10% formalin, was collected three times at 2–3-day intervals. Results . Parasitological examination of the stool specimens showed intestinal parasitic infestations in 47 children (2.57% of the study group. Only 7 children were infested with pathogenic parasites (6 cases of giardiasis and 1 enterobiasis and required antiparasitic treatment. 17 children were infested with potentially pathogenic protozoa (Blasocystis sp. and 26 with non-pathogenic protozoa ( Entamoeba coli , Endolimax nanai , but because of lack of gastrointestinal symptoms (asymptomatic carriage they did not require a treatment. Conclusions . Performed examination show low infection rates among children from a large urban agglomeration. In the absence of epidemiological surveillance over the prevalence of the majority of intestinal parasitic diseases in Poland, and because some diagnostic centres generate positive test results using valueless methods, the propagation of parasitological diagnostics in light microscopy in direction of prevalence of intestinal parasitic infestations, especially among patients with gastrointestinal symptoms, is strongly recommended.

Intestinal helminth infestation is associated with increased bronchial responsiveness in children.

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da Silva, Emerson R; Sly, Peter D; de Pereira, Marilyn U; Pinto, Leonardo A; Jones, Marcus H; Pitrez, Paulo M; Stein, Renato T

2008-07-01

Non-atopic asthma is the predominant phenotype in non-affluent parts of Latin America. We recently reported that infestation with Ascaris lumbricoides increased the risk of non-atopic asthma in less affluent areas of Brazil but the mechanism is unclear. The present study was conducted to determine whether helminth infestation is associated with heightened bronchial responsiveness (BHR), a common finding in asthma. A random sample of 50 asthmatic and 50 non-asthmatic controls (mean age 10.1 years) were selected from a larger cohort (n = 1,011) without knowledge of their helminth infestation status. Three stool samples were collected from each child on different days and each sample was analyzed by the Kato-Katz method for quantitative determination of helminth eggs. Bronchial provocation tests were performed with inhaled 4.5% hypertonic saline using the ISAAC Phase II standardized protocol. There was no difference between the prevalence of positive BHR in the asthmatics (20.4%) compared with the controls (14.6%) (P = 1.0). Helminth infestation was detected in 24.0% of children, with A. lumbricoides being the most common. Children with high load infestation (>or=100 eggs/g) were five times more likely to have BHR than children with low load or no infestation. Despite the small sample size the results of the present study suggest that the link between high load helminth infestation and non-atopic asthma may be mediated via heightened bronchial responsiveness, possibly due to an inflammatory response to the pulmonary phase of the helminth life cycle.

Effect of azadirachtin on haematological and biochemical parameters of Argulus-infested goldfish Carassius auratus (Linn. 1758).

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Kumar, Saurav; Raman, R P; Kumar, Kundan; Pandey, P K; Kumar, Neeraj; Mallesh, B; Mohanty, Snatashree; Kumar, Abhay

2013-08-01

Argulosis hampers aquaculture production and alters the host physiology and growth. Azadirachtin is recognized as a potential antiparasitic agent against Argulus sp. The present study aimed to investigate the effect of different concentration of azadirachtin solution on haematological and serum biochemical parameters of Argulus-infested goldfish Carassius auratus. Ninety Argulus-infested goldfish were randomly divided into six equal groups. Fish of group 1-5 were treated with azadirachtin solution through bath of 1, 5, 10, 15 and 20 mg L(-1) as T1, T2, T3, T4 and T5, respectively, and group 6 was exposed to 2% DMSO solution without azadirachtin and considered as negative control T0(-). Along with six treatment groups, a positive control T0(+) of healthy goldfish free from Argulus infestation was also maintained. Parasitic mortality was evaluated after 3 days of consecutive bath treatment. After 7 days of post-treatment, the blood and serum were drawn from each of the treatment groups and haematological and serum biochemical parameters were evaluated. Total leucocyte count (TLC), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), blood glucose, total protein (TP), globulin, serum glutamate oxaloacetate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) were significantly (p azadirachtin have notable effects on activity of vital tissues function and physiology of the host. Argulus spp. from infested goldfish could be eliminated using bath treatment with solution of azadirachtin having concentration of 15 mg L(-1) and that also shifted haematological and serum biochemical parameters towards homeostasis.

Bark-beetle infestation affects water quality in the Rocky Mountains of Colorado

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Mikkelson, K.; Dickenson, E.; Maxwell, R. M.; McCray, J. E.; Sharp, J. O.

2012-12-01

In the previous decade, millions of acres in the Rocky Mountains of Colorado have been infested by the mountain pine beetle (MPB) leading to large-scale tree mortality. These vegetation changes can impact hydrological and biogeochemical processes, possibly altering the leaching of natural organic matter to surrounding waters and increasing the potential for harmful disinfection byproducts (DBP) during water treatments. To investigate these adverse outcomes, we have collected water quality data sets from local water treatment facilities in the Rocky Mountains of Colorado that have either been infested with MPB or remain a control. Results demonstrate significantly more total organic carbon (TOC) and DBPs in water treatment facilities receiving their source water from infested watersheds as compared to the control sites. Temporal DBP concentrations in MPB-watersheds also have increased significantly in conjunction with the bark-beetle infestation. Interestingly, only modest increases in TOC concentrations were observed in infested watersheds despite more pronounced increases in DBP concentrations. Total trihalomethanes, a heavily regulated DBP, was found to approach the regulatory limit in two out of four reporting quarters at facilities receiving their water from infested forests. These findings indicate that bark-beetle infestation alters TOC composition and loading in impacted watersheds and that this large-scale phenomenon has implications on the municipal water supply in the region.

Infestation Level Influences Oviposition Site Selection in the Tomato Leafminer Tuta absoluta (Lepidoptera: Gelechiidae

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Thomas Bawin

2014-11-01

Full Text Available The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae, is a devastating pest that develops principally on solanaceous plants throughout South and Central America and Europe. In this study, we tested the influence of three levels of T. absoluta infestations on the attraction and oviposition preference of adult T. absoluta. Three infestation levels (i.e., non-infested plants, plants infested with 10 T. absoluta larvae, and plants infested with 20 T. absoluta larvae were presented by pairs in a flying tunnel to groups of T. absoluta adults. We found no differences in terms of adult attraction for either level of infestations. However, female oviposition choice is influenced by larvae density on tomato plants. We discuss the underlying mechanisms and propose recommendations for further research.

Eco-bio-social determinants for house infestation by non-domiciliated Triatoma dimidiata in the Yucatan Peninsula, Mexico.

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Eric Dumonteil

Full Text Available BACKGROUND: Chagas disease is a vector-borne disease of major importance in the Americas. Disease prevention is mostly limited to vector control. Integrated interventions targeting ecological, biological and social determinants of vector-borne diseases are increasingly used for improved control. METHODOLOGY/PRINCIPAL FINDINGS: We investigated key factors associated with transient house infestation by T. dimidiata in rural villages in Yucatan, Mexico, using a mixed modeling approach based on initial null-hypothesis testing followed by multimodel inference and averaging on data from 308 houses from three villages. We found that the presence of dogs, chickens and potential refuges, such as rock piles, in the peridomicile as well as the proximity of houses to vegetation at the periphery of the village and to public light sources are major risk factors for infestation. These factors explain most of the intra-village variations in infestation. CONCLUSIONS/SIGNIFICANCE: These results underline a process of infestation distinct from that of domiciliated triatomines and may be used for risk stratification of houses for both vector surveillance and control. Combined integrated vector interventions, informed by an Ecohealth perspective, should aim at targeting several of these factors to effectively reduce infestation and provide sustainable vector control.

Mountain pine beetle infestations in relation to lodgepole pine diameters

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Walter E. Cole; Gene D. Amman

1969-01-01

Tree losses resulting from infestation by the mountain pine beetle (Dendroctonus ponderosae Hopkins) were measured in two stands of lodgepole pine (Pinus contorta Dougl.) where the beetle population had previously been epidemic. Measurement data showed that larger diameter trees were infested and killed first. Tree losses...

Cases of bed bug (Cimex lectularius infestations in Northwest Italy

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Federica Giorda

2013-12-01

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

Studies on pest infestation of commercial samples of cowpeas and ...

African Journals Online (AJOL)

Weight loss in both the infested beans and maize increased with increase in the number of emergence holes. Public health implications of the insect infestation of the stored products such as reduction in nutritive value and accumulation of undesirable residues were discussed. Improved storage and pest control techniques ...

Examination of the pest status of corn-infesting Ulidiidae (Diptera).

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Goyal, Gaurav; Nuessly, Gregg S; Seal, Dakshina R; Steck, Gary J; Capinera, John L; Meagher, Robert L

2012-10-01

Larvae of 11 species of picture-winged flies (Diptera: Ulididae) are known to feed on corn plants (Zea mays L.) in the western hemisphere. Larvae emerge from eggs deposited in leaf axils and corn silk to feed mostly within ears, but the primary versus secondary nature (i.e., pest status) of their infestation is not known for all of these species. Choice and no-choice tests by using a split-plot design were conducted in greenhouse and field trials to determine the pest status on sweet corn of three of these species found in Florida: Chaetopsis massyla (Walker), Euxesta eluta Loew, and E. stigmatias Loew. The main treatments (uninfested ears and ears experimentally infested with either Spodoptera frugiperda [Lepidoptera: Noctuidae] or E. eluta larvae) were applied at first silk. The subtreatments (C. massyla, E. eluta, or E. stigmatias adults caged on ears) were applied 7 d later and maintained for 10 d. All three fly species were reared from uninfested and experimentally infested ears in both choice and no-choice tests in greenhouse and field trials confirming both primary and secondary modes of ear infestation. More flies of all three species emerged from ears that were preinfested with S. frugiperda compared with uninfested ears suggesting either preference for or greater survival within ears previously infested by S. frugiperda. Fewer E. eluta and E. stigmatias emerged from ears preinfested with E. eluta in no-choice field tests, suggesting that previous infestation by this fly may negatively affect oviposition or that older fly larvae affect survival of neonate larvae. All three species studied here should be considered primary pests that can render unprotected sweet corn ears unmarketable.

Neural correlates of delusional infestation responding to aripiprazole monotherapy: a case report

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Ponson L

2015-02-01

Full Text Available Laura Ponson,1,2 Frédéric Andersson,1 Wissam El-Hage1,2 1Université François-Rabelais de Tours, Inserm, Imagerie et Cerveau UMR U930, Tours, France, 2CHRU de Tours, Clinique Psychiatrique Universitaire, Tours, France Background: The pathophysiology and appropriate pharmacological interventions for delusional infestation remain unknown.Case presentation: Here, we report a case of primary delusional infestation successfully treated with aripiprazole. We performed functional magnetic resonance imaging (fMRI to investigate brain structures and functional modifications. Before antipsychotic treatment, pre- versus post-treatment fMRI images revealed a marked increase in brain activation in the supplementary motor area (SMA.Conclusion: Our results highlight the efficacy and safety of aripiprazole in the treatment of delusional infestation and the possible role of SMA dysfunction in delusional infestation. Indeed, our results suggest that psychiatric improvement of delusional infestation is associated with normalization of brain activity, particularly in the SMA. Keywords: supplementary motor area, antipsychotics, fMRI

Modeling Math Growth Trajectory--An Application of Conventional Growth Curve Model and Growth Mixture Model to ECLS K-5 Data

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Lu, Yi

2016-01-01

To model students' math growth trajectory, three conventional growth curve models and three growth mixture models are applied to the Early Childhood Longitudinal Study Kindergarten-Fifth grade (ECLS K-5) dataset in this study. The results of conventional growth curve model show gender differences on math IRT scores. When holding socio-economic…

Seasonal infestation of donkeys by lice: phenology, risk factors and management.

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Ellse, L; Burden, F A; Wall, R

2014-07-14

A longitudinal study was undertaken over a 21 months period to examine the seasonal abundance of lice infesting donkeys, the risk factors which predispose donkeys to infestation and the effectiveness of louse management. All the lice seen were Bovicola (Werneckiella) ocellatus. A strong seasonal pattern, which was correlated with mean monthly temperature, was observed with higher prevalence and intensity in the cooler, winter months (October-March). Overall infestation in these animals was over-dispersed, suggesting that some individuals are strongly predisposed to infestation. Donkey age and mean hair length were characteristics which affected louse prevalence: older and younger donkeys and donkeys with longer hair harboured the highest numbers of lice. However, the practice of coat-clipping, to reduce the infestation, resulted in a lower louse prevalence only in the summer, suggesting that clipping is not an effective form of louse control in cooler months. Higher louse burdens were associated with larger areas of visible excoriation and hair damage, suggesting that B. ocellatus does adversely impact animal welfare. However, the ability of animal carers to estimate louse presence or absence accurately on an individual donkey was not sufficiently high to allow targeted selective treatment of heavily infested animals to be employed effectively. As animals are housed in closed herds these findings suggest that clipping in the summer and treating all animals with insecticide in late autumn, prior to turn-in may be an effective louse management strategy. Copyright © 2014 Elsevier B.V. All rights reserved.

Circulating oxidative stress caused by Psoroptes natalensis infestation in Indian water buffaloes.

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Mahajan, Sumit; Panigrahi, Padma Nibash; Dey, Sahadeb; Dan, Ananya; Kumar, Akhilesh; Mahendran, K; Maurya, P S

2017-09-01

The present study reports the circulating oxidative stress associated with Psoroptes natalensis infestation in Indian water buffaloes. Three non-descriptive water buffaloes, age ranging between 4 and 9 years, presented to Referral Veterinary Polyclinic, IVRI, for treatment served as clinical subject. The infested animals were treated with Ivermectin subcutaneously and Amitraz topically along with antioxidant like ascorbic acid, Vitamin E and selenium. The level of lipid peroxidase was significantly higher (3.94 ± 0.34) in Psoroptes infested buffalo and was reduced significantly ( P  ≤ 0.05) after treatment (1.56 ± 0.40). The significantly higher levels of MDA before treatment signify the role of lipid peroxide mediated skin lesions in P. natalensis infested buffaloes. Similarly the activities of the body antioxidant like GSH and CAT were significantly higher ( P  ≤ 0.05) after treatment. The less level of the body antioxidant (GSH) and reduced activities of the antioxidant enzymes like CAT and SOD before treatment imply that Psoroptes mite-infested buffaloes were in a state of significant oxidative stress. The study provides information on oxidative stress indices in P. natalensis infested buffaloes and gives additional insight regarding the pathogenesis of the disease and its management.

Stored product mites (Acari: Astigmata) infesting food in various types of packaging.

Science.gov (United States)

Hubert, Jan; Nesvorna, Marta; Volek, Vlado

2015-02-01

From 2008 to 2014, stored product mites have been reported from prepackaged dried food on the market in the Czech Republic. The infestation was by Carpoglyphus lactis (L.) in dried fruits and Tyrophagus putrescentiae (Schrank) in dog feed. The infestation is presumably caused by poor protection of the packages. We compared various packaging methods for their resistance to mites using dried apricots and dog feed in laboratory experiments. The trial packages included nine different plastic films, monofilm, duplex and triplex, and one type of plastic cup (ten replicates per packaging type). All packaging materials are available on the Czech market for dried food products. The samples of dried food were professionally packed in a factory and packaged dried apricots were exposed to C. lactis and dog food to T. putrescentiae. After 3 months of exposure, the infestation and mite density of the prepackaged food was assessed. Mites were found to infest six types of packages. Of the packaging types with mites, 1-5 samples were infested and the maximum abundance was 1,900 mites g(-1) of dried food. Mites entered the prepackaged food by faulty sealing. Inadequate sealing is suggested to be the major cause of the emerged infestation of dried food.

A Two Years Study of Ticks infesting Goats and Sheep in Abha, Saudi Arabia

International Nuclear Information System (INIS)

AlKhalifa, Mohamed S.; Khalil, Galila M.; Diab, Fathi M.

2007-01-01

The weather in Abha was characterized by a temperature of 11.7-23.7 degree C, a relative humidity 0f 40-92% and rainfall of 0.2-275mm during a study period of 1990 and 1991. More ticks infested the goats in 1990 than in 1991 while more ticks infested sheep in 1991 than in 1990. The tick species collected monthly from 10 goats during these years were, respectively, Rhipicephalus turanicus (95.1 and 67.1%), Haemaphysalis sulcata (4.0 and 25.8%), Hyalomma anatolicum anatolicum (0.2 and 1.0%) and H. impeltatum (0.7 and 6.1%). Goat infestation rate with R. turanicus was 60-100% in 1990 with peaks in January, April, July, November and December when 90-100% of the goats were infested with 6.3-8.3 ticks/goat. In 1991, goat infestation rate was 10-100% with peaks in April, July and December when all goats were infested with 5.6-9.0 ticks/goat, with a sex ratio of 0.40:1-2.00:1 in both years, respectively. The ticks collected monthly from 10 sheep during these years were, respectively, R. turanicus (89.2 and 86.2%), Haem. sulcata (5.7 and 4.9%), H. a. anatolicum (1.2 and 1.0%), H. a. excavatum (0.7 and 1.2%), H. dromedarii (0.9 and 0.4%), H. marginatum rufipes (1.4 and 4.1%), H. m. turanicum (0.0 and 1.2%) and H. impeltatum (0.9 and 1.0%). Sheep infestation rate with R. turanicus was 30-100% in both years with a peak in June in 1990 when all sheep were infested with 13.8 ticks/sheep and 2 peaks in April and June in 1991 when all sheep were infested with 25.0-29.6 ticks/sheep, with a sex ratio of 0.2:1-2.6:1 and 0.6:1-4.5:1 in these years, respectively. The change in R. turanicus infestation in goats and sheep was not correlated with temperature, relative humidity or rainfall during both years except for the infestation in sheep in 1991, which was positively correlated with rainfall. With the exception of R. turanicus and Haem. sulcata, the other tick species infest primarily animals other than sheep and goats. It is recommended that control measures be directed toward the

Dipylidium caninum infection in dogs infested with fleas.

Science.gov (United States)

Wani, Z A; Allaie, I M; Shah, B M; Raies, A; Athar, H; Junaid, S

2015-03-01

The present study pertains to the Dipylidium caninum infection in dogs infested with fleas. Twenty dogs were presented to the Divison of Surgery, SKUAST-K for different surgical procedures. Majority of the dogs had a history of pruritus, loss of weight as well as rubbing their perineal region against the wall. On external examination dogs were found infested with Ctenocephalides canis. When dogs were anesthetized, motile segments were seen coming out of their anus, which were then identified as mature segments of D. caninum.

Preventive efficacy of NexGard Spectra® against Dipylidium caninum infection in dogs using a natural flea (Ctenocephalides felis) infestation model

OpenAIRE

Beugnet Frédéric; Meyer Leon; Fourie Josephus; Larsen Diane

2017-01-01

The efficacy of a monthly oral endectocide product, NexGard Spectra? (Merial), a combination of afoxolaner and milbemycin oxime, was evaluated in a flea (Ctenocephalides felis) challenge model for the prevention of Dipylidium caninum tapeworm infection in dogs. The efficacy of treatment with NexGard Spectra? was assessed in 10 dogs following weekly flea infestation with metacestode naturally infected fleas and compared with that in 10 untreated control dogs. The 100 fleas deposited weekly on ...

EFFECT OF REPEATED INFESTATION OF CHRYSOMYIA BEZZIANA ON WEIGHT OF ITS LARVAE

Directory of Open Access Journals (Sweden)

S. Baidya

2016-12-01

Full Text Available There are about 20 species of obligate and 50 species of facultative myiasis producing flies found in India. Out of these, the Old World screwworm fly Chrysomyia bezziana is the most important obligate myiasis-causing fly. Three repeated infestations at an interval of one month each, larvae of C. bezziana developed in the clinically abraded wounds in cattle. Average weights of the larvae during the 1st, 2nd and 3rd infestation were 62.18+0.441, 56.53+0.389 and 56.45+0.485 mg, respectively. Statistical analysis revealed significant (P<0.05 reduction in larval weight during the 2nd and 3rd infestations compared to the larval weight of the initial infestation.

Mineral content of insect infested stored legumes treated with edible oils.

Science.gov (United States)

Modgil, R

2000-12-01

Mineral content of three insect (pulse beetle, Callosobruchus chinensis L.) infested legumes viz. chick pea, mung pea and pigeon pea stored for six months and treated with three edible oils viz. groundnut, mustard and coconut oil has been studied. With increase in storage period significant increase in calcium, phosphorus and iron content of untreated legumes was observed. After three months of storage slight increase in three minerals was observed in the legumes treated with coconut oil which continued till the end of sixth months as compared to other two oil treated counterparts. The storage period was associated with insect infestation which in turn influenced the mineral content of legumes. Ground nut and mustard oils were able to protect legumes for six months against insect infestation when applied in small amounts (0.5%). Whereas coconut oil had protective effect against insect infestation for four months only.

High exposure to Tunga penetrans (Linnaeus, 1758 correlates with intensity of infestation

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Hermann Feldmeier

2006-02-01

Full Text Available Tungiasis is a parasitic skin disease widespread in resource-poor urban and rural communities in Brazil. Inhabitants of an urban slum in Northeast Brazil were examined for the presence of tungiasis lesions and followed-up twice a week for a period of three weeks. Each time the number, stages, and topographic localization of lesions were recorded on a documentation sheet. The infestation rate (number of newly embedded sand fleas per individual and day remained stable during the observation period. The infestation rate was significantly related to the intensity of infestation (total number of lesions present (rho = 0.70, p < 0.0001 and the proportion of viable lesions (rho = 0.28, p < 0.0001. The results indicate that in an endemic area the infestation intensity and the proportion of viable lesions can be used as a proxy to assess the exposure of individuals at risk for tungiasis. Persistently high infestation rates during the transmission season favour the use of prevention measures against invading sand fleas (such as a repellent rather than a drug to kill already embedded parasites.

Transgenic Expression of a Functional Fragment of Harpin Protein Hpa1 in Wheat Represses English Grain Aphid Infestation

Institute of Scientific and Technical Information of China (English)

XU Man-yu; ZHOU Ting; ZHAO Yan-ying; LI Jia-bao; XU Heng; DONG Han-song; ZHANG Chun-ling

2014-01-01

The harpin protein Hpa1 produced by the rice bacterial blight pathogen promotes plant growth and induces plant resistance to pathogens and insect pests. The region of 10-42 residues (Hpa110-42) in the Hpa1 sequence is critical as the isolated Hpa110-42 fragment is 1.3-7.5-fold more effective than the full length in inducing plant growth and resistance. Here we report that transgenic expression of Hpa110-42 in wheat induces resistance to English grain aphid, a dominant species of wheat aphids. Hpa110-42-induced resistance is effective to inhibit the aphid behavior in plant preference at the initial colonization stage and repress aphid performances in the reproduction, nymph growth, and instar development on transgenic plants. The resistance characters are correlated with enhanced expression of defense-regulatory genes (EIN2, PP2-A, and GSL10) and consistent with induced expression of defense response genes (Hel, PDF1.2, PR-1b, and PR-2b). As a result, aphid infestations are alleviated in transgenic plants. The level of Hpa110-42-induced resistance in regard to repression of aphid infestations is equivalent to the effect of chemical control provided by an insecticide. These results suggested that the defensive role of Hpa110-42 can be integrated into breeding germplasm of the agriculturally signiifcant crop with a great potential of the agricultural application.

Efficacy of herbicide seed treatments for controlling Striga infestation of Sorghum

NARCIS (Netherlands)

Tuinstra, M.R.; Soumana, S.; Al-Khatib, K.; Kapran, I.; Toure, A.; Ast, van A.; Bastiaans, L.; Ochanda, N.W.; Salami, I.; Kayentao, M.; Dembele, S.

2009-01-01

Witchweed (Striga spp.) infestations are the greatest obstacle to sorghum [Sorghum bicolor (L.) Moench] grain production in many areas in Africa. The objective of this study was to evaluate the efficacy of herbicide seed treatments for controlling Striga infestation of sorghum. Seeds of an

Changes in the free amino acid composition of Capsicum annuum (pepper) leaves in response to Myzus persicae (green peach aphid) infestation. A comparison with water stress.

Science.gov (United States)

Florencio-Ortiz, Victoria; Sellés-Marchart, Susana; Zubcoff-Vallejo, José; Jander, Georg; Casas, José L

2018-01-01

Amino acids play a central role in aphid-plant interactions. They are essential components of plant primary metabolism, function as precursors for the synthesis of defense-related specialized metabolites, and are major growth-limiting nutrients for aphids. To quantify changes in the free amino acid content of pepper (Capsicum annuum L.) leaves in response to green peach aphid (Myzus persicae Sulzer) feeding, plants were infested with a low (20 aphids/plant) or a high (200 aphids/plant) aphid density in time-course experiments ranging from 3 hours to 7 days. A parallel experiment was conducted with pepper plants that had been subjected to water stress. Factor Analysis of Mixed Data revealed a significant interaction of time x density in the free amino acid response of aphid-infested leaves. At low aphid density, M. persicae did not trigger a strong response in pepper leaves. Conversely, at high density, a large increase in total free amino acid content was observed and specific amino acids peaked at different times post-infestation. Comparing aphid-infested with water-stressed plants, most of the observed differences were quantitative. In particular, proline and hydroxyproline accumulated dramatically in response to water stress, but not in response to aphid infestation. Some additional differences and commonalities between the two stress treatments are discussed.

Infestation of Broad Bean (Vicia faba) by the Green Stink Bug (Nezara viridula) Decreases Shoot Abscisic Acid Contents under Well-Watered and Drought Conditions.

Science.gov (United States)

Ederli, Luisa; Brunetti, Cecilia; Centritto, Mauro; Colazza, Stefano; Frati, Francesca; Loreto, Francesco; Marino, Giovanni; Salerno, Gianandrea; Pasqualini, Stefania

2017-01-01

The response of broad bean ( Vicia faba ) plants to water stress alone and in combination with green stink bug ( Nezara viridula ) infestation was investigated through measurement of: (1) leaf gas exchange; (2) plant hormone titres of abscisic acid (ABA) and its metabolites, and of salicylic acid (SA); and (3) hydrogen peroxide (H 2 O 2 ) content. Furthermore, we evaluated the effects of experimentally water-stressed broad-bean plants on N. viridula performance in terms of adult host-plant preference, and nymph growth and survival. Water stress significantly reduced both photosynthesis ( A ) and stomatal conductance ( g s ), while infestation by the green stink bug had no effects on photosynthesis but significantly altered partitioning of ABA between roots and shoots. Leaf ABA was decreased and root ABA increased as a result of herbivore attack, under both well-watered and water-deprived conditions. Water stress significantly impacted on SA content in leaves, but not on H 2 O 2 . However, infestation of N. viridula greatly increased both SA and H 2 O 2 contents in leaves and roots, which suggests that endogenous SA and H 2 O 2 have roles in plant responses to herbivore infestation. No significant differences were seen for green stink bug choice between well-watered and water-stressed plants. However, for green stink bug nymphs, plant water stress promoted significantly lower weight increases and significantly higher mortality, which indicates that highly water-stressed host plants are less suitable for N. viridula infestation. In conclusion two important findings emerged: (i) association of water stress with herbivore infestation largely changes plant response in terms of phytohormone contents; but (ii) water stress does not affect the preference of the infesting insects, although their performance was impaired.

9 CFR 72.12 - Cattle; exposure to tick infestation after treatment or inspection prohibited.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Cattle; exposure to tick infestation... (INCLUDING POULTRY) AND ANIMAL PRODUCTS TEXAS (SPLENETIC) FEVER IN CATTLE § 72.12 Cattle; exposure to tick infestation after treatment or inspection prohibited. The cattle shall not be exposed to tick infestation...

ECTOPARASITES INFESTING LIVESTOCK IN THREE LOCAL ...

African Journals Online (AJOL)

Administrator

they may also transmit pathogens, thereby acting as vectors of diseases (Parola et al., ... transmit pathogens that causes some human diseases such as lyme diseases ... annulatus (14.6%), Hyloma trucatus (4.7%) infesting dogs in. Wurukum ...

Effect of conservation tillage and peat application on weed infestation on a clay soil

Directory of Open Access Journals (Sweden)

P. VANHALA

2008-12-01

Full Text Available Amendment of soil with peat is an attempt to avoid crop yield variation in the transition to conservation tillage, as it improves seedbed conditions and crop growth in drought-sensitive clay soils. Weed infestations were compared in 1999-2000 between the original and peat-amended clay (Typic Cryaquept, very fine, illitic or mixed under different autumn tillage systems in an oats-barley rotation. In a field experiment, sphagnum peat (H = 4 had been spread (0.02 m 3 m -2 on the soil surface in August 1995. Tillage treatments included mouldboard ploughing (to 20 cm and stubble cultivations of different working depths (8 or 15 cm and intensity (once or twice. Weed biomass and density were assessed by an area of 1 m 2 per field plot in August 1999-2000 and June 2000. The 1999 season was dry, but soil moisture conditions were more favourable in 2000. Peat application tended to increase the number of volunteer oats and Chenopodium album in 1999, while decreasing Galium spurium biomass. Ploughing significantly increased the abundance of Chenopodium album and Lamium purpureum in barley (Hordeum vulgare in 1999. Weed infestation was much lower in 2000, and tillage effect on Chenopodium album was minor in oats (Avena sativa. Growth of Lamium purpureum and Fumaria officinalis was stimulated in ploughed soils both years. Intensity and working depth of stubble cultivation had no significant effect on weeds.;

deaminase from plant growth promoting rhizobacteria in Striga

African Journals Online (AJOL)

Experiments were conducted in pots to determine the growth effect of different rhizobacteria on maize under Striga hermonthica infestation. Three bacteria were selected based on their plant growth promoting effects. Whole bacterial cells of the rhizobacteria were used to amplify 1-amino-cyclopropane-1-carboxylic acid ...

A case report of Dermanyssus gallinae infestation in three cats.

Science.gov (United States)

Di Palma, Antonella; Leone, Federico; Albanese, Francesco; Beccati, Massimo

2018-04-30

Dermanyssus gallinae is a major threat for the poultry industry; these mites also feed on the blood of many other birds, small mammals and potentially humans. Three cats with dermatitis attributed to D. gallinae infestation. Two 40-day-old kittens, living in a rural area, and one 7-year-old female indoor cat, were presented with a pruritic skin condition. Mite specimens were collected from the cats and examined by light and scanning electron microscopy. Cytological and histological examinations of the skin lesions were performed. A diagnosis of D. gallinae infestation was made after identification of the mites. Histological findings were compatible with eosinophilic dermatitis. Clinical improvement was noted two weeks after treatment. The two kittens showed chronic blood loss which reflects the ability of D. gallinae mites to switch host. For the indoor cat, mites were presumed to be carried by birds regularly present on the balcony of the apartment. This demonstrates that mite infestation is possible even in urban areas, through contact with birds or their abandoned nests. When birds are not present, cats or other small mammals as well as humans, can be infested. © 2018 ESVD and ACVD.

Wide Ranging Insect Infestation of the Pioneer Mangrove Sonneratia alba by Two Insect Species along the Kenyan Coast.

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Elisha Mrabu Jenoh

Full Text Available Insect infestation of mangroves currently threatens mangrove forest health and management. In the Western Indian Ocean region, little is known about insect damage to mangroves despite the fact that numerous infestations have occurred. In Kenya, infestations of Sonneratia alba have persisted for almost two decades, yet the taxonomic identity of the infesting pest(s, the extent of infestation, the pests' biology, the impacts of infestation on host and the ecosystem, the host's defensive strategies to the infestation are poorly understood. S. alba is a ubiquitous, pioneer mangrove species of the Indo-Pacific, occurring along the waterfront in a variety of mangrove ecosystem settings. Our main objectives were to identify the pest(s responsible for the current dieback of S. alba in Kenya, and to determine the extent of infestation. To identify the pests responsible for infestation, we trapped emergent insects and reared larvae in the laboratory. To determine the overall extent of infestation within the S. alba zone, we assessed nine sites along the entire Kenyan coastline for the presence or absence of infested mangroves. Insect infestation in two mangrove embayments (Gazi and Mida was quantified in depth. Two wood-boring insects were identified: a metarbelid moth (Lepidoptera, Cossoidea of undescribed genus and the beetle Bottegia rubra (Cerambycidae, Lamiinae.The metarbelid moth infests mangroves in both northern (from Ngomeni to Kiunga and southern regions (from Vanga to Mtwapa of the Kenyan coast. B. rubra appeared in low density in Gazi, and in high density in Mida, Kilifi, and Ngomeni, with densities gradually decreasing northward. Insect infestation levels reached 18% in Gazi and 25% of S. alba stands in Mida. Our results indicate that B. rubra has the ability to infest young mangrove trees and expand its range, posing a danger to rehabilitation efforts where plantations have been established. Thus, there is great need for forest managers to

Tick infestation in human beings in the Nilgiris and Kancheepuram district of Tamil Nadu, India.

Science.gov (United States)

Soundararajan, C; Nagarajan, K; Arul Prakash, M

2018-03-01

Thirteen human beings were infested with ticks at Sandynallah and Gudalur of the Nilgiris district and Mottur Suruvakkam of Kancheepuram district of Tamil Nadu from January 2016 to December 2016. The collected ticks were identified as Rhipicephalus haemaphysaloides , Otobius megnini and Hyalomma isaaci. The tick infestation was observed more on the persons working with animals (sheep and goats) than those working in tea estate. The person infested with R. haemaphysaloides revealed erythematous papule (2 mm size) and inflammatory lesion up to 16 days whereas, the people infested with H. isaaci showed continuous itching and irritation for > 6 months and wound formation (0.5 cm) at the biting site. The people infested with O. megnini showed irritation, vomiting sensation and fever.

Head lice infestation in school children of a low socio- economy ...

African Journals Online (AJOL)

STORAGESEVER

2008-07-04

Jul 4, 2008 ... In the old Gaza city and the rural village Jabalia within the Gaza Governorate the rate of infestation with lice was 14.1% in the primary school girls. (Al-Shawa, 2006). In a high socio-economy area in Izmir,. Turkey, 4.2% of the studied population of the secondary and elementary school children were infested ...

Head Lice Infestation (Pediculosis and Associated Factors among Primary School Girls in Sirik County, Southern Iran

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Alireza Sanei-Dehkordi

2017-12-01

Full Text Available Background Head lice infestation (pediculosis is a serious health problem that can cause a high level of anxiety and psychological frustration, especially in developing countries.Socio-demographic factors are important determinants of the occurrence of head lice infestation. This study aimed to determine the head lice infestations and the factors affecting the rate of infestationin primary school girls.   Materials and Methods In this cross-sectional study, a total of 358 school girls from two urban and three rural primary school girls in Sirik County, Southern Iran, were randomly selected. For the diagnosis of head lice infestation, students were examined carefully by visual inspection of the scalp and hair for the presence of lice. Self-administered questionnaire was used to collect data on socio-demographic and associated factors of head lice infestation. SPSS version 21.0 was used to analyze the data. Results The prevalence of head lice infestation among primary school girls was 56.15%. There were significant associations between head lice infestation and age (p

Annoying vacation souvenir: Fish tapeworm (Diphyllobothrium sp.) infestation in an Austrian fisherman.

Science.gov (United States)

Stadlbauer, Vanessa; Haberl, Renate; Langner, Cord; Krejs, Günter J; Eherer, Andreas

2005-11-01

Diphyllobothriosis is infestation with the fish tapeworm. Although the worldwide incidence has decreased in recent decades, increased travel and the new popularity of dishes involving raw fish (e.g. sushi) may provide a higher risk of infestation in formerly low-risk areas. We report an Austrian fisherman who passed a 75 cm tapeworm segment in his stool. Infestation presumably occurred 14 months earlier during a fishing tour in Alaska. At presentation, the patient was asymptomatic, reported no weight loss and showed neither anaemia nor eosinophilia. He was cured with a single dose of 10 mg/kg body weight praziquantel.

Biological control potential of the obligate parasite Pasteuria penetransagainst the root-knot nematode, Meloidogyne incognita infestation in Brinjal.

Science.gov (United States)

Kumari, N Swarna; Sivakumar, C V

2005-01-01

The efficacy of the obligate bacterial parasite, Pasteuria penetrans against the rootknot nematode, Meloidogyne incognita infestation was assessed in brinjal. The seedling pans with sterilized soil were inoculated with nematodes and root powder of P. penetrans were applied at different dosages viz., 0 x 10(6), 0.5 x 10(6) spores and 1 x 10(6) spores/pan. Seeds of brinjal cv Co2 were sown in the pans and seedlings were allowed to grow. The seedlings were transplanted to microplots containing sterilized soil. Observations on nematode infestation and plant growth were recorded at seedling, flowering, and fruiting stages. Nematode infestation was significantly reduced by P. penetrans treatment. There was 22, 75 and 86% reduction in nematode population of soil over control at seedling, flowering and fruiting stages, respectively, at higher spore density (1 x 10(6)). Egg mass production was decreased by 63, 78 and 89% over control at 35 (seedling), 100 (flowering) and 160 (fruiting) days after sowing respectively, at 1 x 10(6) spores treated soil. The parasitizing ability of P. penetrans increased with the age of the crop. At higher spore density the percentage of parasitization was increased from 52.0 (35 days after sowing) to 90.0 (160 days after sowing) %. At these stages of the crop, the spore load per juvenile also increased at the higher dose. The P. penetrans application enhanced the plant growth. The weight of the shoot was increased by 17.6% whereas root weight by 41.0% over the control at fruiting stage. The experimental results revealed the potential use of P. penetrans as biological control agent of M. incognita. Application of P. penetrans spores in the nursery is a good strategy since the mass multiplication is quite difficult.

Infection Courts in Watermelon Plants Leading to Seed Infestation by Fusarium oxysporum f. sp. niveum.

Science.gov (United States)

Petkar, Aparna; Ji, Pingsheng

2017-07-01

Fusarium wilt incited by Fusarium oxysporum f. sp. niveum is a seed-transmitted disease that causes significant yield loss in watermelon production. The pathogen may infect watermelon seeds latently, which can be an important inoculum source and contribute to severe disease outbreak. However, information regarding infection courts of F. oxysporum f. sp. niveum leading to infestation of watermelon seeds is limited. To determine how seeds in watermelon fruit can be infested by F. oxysporum f. sp. niveum during the watermelon growing season, greenhouse and field experiments were conducted in 2014 and 2015 where watermelon flowers and immature fruit were inoculated with F. oxysporum f. sp. niveum. Seeds were extracted from mature watermelon fruit, and infestation of watermelon seeds was determined by isolation of F. oxysporum f. sp. niveum and further confirmed by real-time polymerase chain reaction (PCR) analysis. Inoculation of the pericarp of immature fruit resulted in 17.8 to 54.4% of infested seeds under field conditions and 0.6 to 12.8% of infested seeds under greenhouse conditions when seeds were not surface disinfested prior to isolation. Seed infestation was also detected in 0 to 4.5% of the seeds when seeds were surface disinfested prior to isolation. Inoculation of pistil resulted in 0 to 7.2% and 0 to 18.3% of infested seeds under greenhouse and field conditions when seeds were surface disinfested or not disinfested before isolation, respectively. Inoculation of peduncle resulted in 0.6 to 6.1% and 0 to 10.0% of infested seeds in the greenhouse and field experiments when seeds were surface disinfested or not disinfested before isolation, respectively. Seed infestation was also detected in all the experiments using real-time PCR assay when pericarp or pistil was inoculated, and in three of four experiments when peduncle was inoculated, regardless of whether seeds were surface disinfested or not disinfested. Pericarp and peduncle of immature watermelon fruit

Mountain pine beetle infestation of lodgepole pine in areas of water diversion.

Science.gov (United States)

Smolinski, Sharon L; Anthamatten, Peter J; Bruederle, Leo P; Barbour, Jon M; Chambers, Frederick B

2014-06-15

The Rocky Mountains have experienced extensive infestations from the mountain pine beetle (Dendroctonus ponderosae Hopkins), affecting numerous pine tree species including lodgepole pine (Pinus contorta Dougl. var. latifolia). Water diversions throughout the Rocky Mountains transport large volumes of water out of the basins of origin, resulting in hydrologic modifications to downstream areas. This study examines the hypothesis that lodgepole pine located below water diversions exhibit an increased incidence of mountain pine beetle infestation and mortality. A ground survey verified diversion structures in a portion of Grand County, Colorado, and sampling plots were established around two types of diversion structures, canals and dams. Field studies assessed mountain pine beetle infestation. Lodgepole pines below diversions show 45.1% higher attack and 38.5% higher mortality than lodgepole pines above diversions. These findings suggest that water diversions are associated with increased infestation and mortality of lodgepole pines in the basins of extraction, with implications for forest and water allocation management. Copyright © 2014 Elsevier Ltd. All rights reserved.

Define Colony Number of Subterranean Termites Coptotermes gestroi (Isoptera: Rhinotermitidae) in Selected Infested Structures

International Nuclear Information System (INIS)

Abdul Hafiz Abdul Majid; Abu Hassan Ahmad

2015-01-01

Termites are one of the social insects living in large colonies that can cause economic loss. The objective of this study was to estimate foraging territory of infested subterranean termites on building structure. A mark-recapture study was conducted on eight Coptotermes gestroi colonies located at selected infested building structures in Penang, Malaysia. From the foraging study, the population of C. gestroi was estimated to be within the range of 106,592±6,968 to 4,185,000±2,127,328. Additionally, the foraging territory was from 13 to 300 m 2 of the infested building structures. Meanwhile the maximum foraging distance was from 4 to 30 m of the infested structures. The results indicated that each of the building structures was infested by a single colony. This study also showed that the triple mark recapture technique used to estimate the population size of the termite colony was capable of providing rough estimates of foraging population of C. gestroi. (author)

Infestation of Pseudopiazurus papayanus (Marshall) (Coleoptera: Curculionidae) on Carica spp. and Vasconcella spp. genotypes

International Nuclear Information System (INIS)

Fancelli, Marilene; Sanches, Nilton F.; Dantas, Jorge L.L.; Caldas, Ranulfo C.; Morales, Cinara F.G.

2008-01-01

The papaya borer weevil, Pseudopiazurus papayanus (Marshall), is generally considered a secondary pest, but it has been reported in high infestations in Northeast Brazil. This work aimed at evaluating the occurrence of P. papayanus and reporting its infestation level in papaya genotypes kept at the germplasm bank of EMBRAPA Cassava and Tropical Fruits (Cruz das Almas, Bahia, Brazil). The number of larvae, pupae and adults found in each plant of 65 Carica spp. genotypes and of three Vasconcella spp. genotypes was registered in three to five plants of each genotype, by cutting the exsudating trunks lengthwise. Papaya borer weevil was found in C. papaya and V. cauliflora but not in those of V. quercifolia. Among the evaluated genotypes, 52.4% of those belonging to the Solo group were infested, against 25.0% of the Formosa group. Larval infestation was the best criterion for sorting out genotypes concerning this insect infestation. This is also the first occurrence of the papaya borer weevil . (author)

Gamma irradiation as a quarantine treatment for carambolas infested with Caribbean fruit flies

International Nuclear Information System (INIS)

Gould, W.P.; Windeguth, D.L. von

1991-01-01

Carambolas infested with the Caribbean fruit fly Anastrepha suspensa (Loew), eggs and larvae were exposed to ionizing gamma radiation. Probit 9 was estimated to be 22.95 Gy (95% fiducial limits 16.68 Gy - 49.73 Gy). Over 100,000 immature A. suspensa infesting carambolas were treated at 50 Gy with no adult survivors. This dose did not cause any observable damage to the fruit. The 50 Gy dose satisfies quarantine requirements for treatment of fruits exposed from fruit fly infested areas. (author) [es

Tick infestation on wild snakes in northern part of western Ghats of India.

Science.gov (United States)

Pandit, Pranav; Bandivdekar, Ruta; Geevarghese, G; Pande, Satish; Mandke, Omkar

2011-05-01

In total, 167 individuals of 30 species of snakes belonging to 22 genera and five families were examined for tick infestation from November 2008 to March 2010. Only two species of snakes, Ptyas mucosa (L., 1758) (Indian rat snake) and Naja naja (L., 1758) (spectacled cobra), were found infested by ticks. All ticks collected were identified to be Amblyomma gervaisi [previously Aponomma gervaisi (Lucas, 1847) 1. The average prevalence of these ticks on Indian rat snakes (n=48) was 29.16%, with abundance of 7.02 ticks per individual; on spectacled cobras (n=20), average prevalence was 30.00%, with abundance of 6.9 ticks per individual. The nymphs and males were predominant. All the ticks were found on the dorsal aspect of the body of the snake, and no ticks were recorded on the head, tail, or ventral body. The rate of tick infestation was highest in scrubland and was lowest in evergreen forests. Female Indian rat snakes showed higher tick infestation rates than male Indian rat snakes. Using Mann-Whitney U test, we found that longer snakes of both species had significantly higher rate of tick infestation in both the species of snakes.

Distribution and infestation levels of Crypticerya multicicatrices Kondo and Unruh (Hemiptera: Monophlebidae on San Andrés island

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Takumasa Kondo Kondo

2014-01-01

Full Text Available The fluted scale Crypticerya multicicatrices (Hemiptera: Monophlebidae is an invasive insect that became a major pest on the island of San Andrés. To generate control strategies for this insect, its distribution and infestation levels on palm species, fruit trees, leguminous trees and other plant species were determined during January 14–18, 2013. A total of 96 points were sampled in order to determine the distribution of the insect on the island. During the study, the fluted scale was found distributed throughout the island of San Andrés, including Haynes Cay and Johnny Cay. The palms were the plants with the highest levels of infestation, 70.8% had some degree of infestation (37.5% high infestation levels; followed by fruit trees which had 65.6% with some degree of infestation (30.2% high infestation levels; followed by leguminous trees which had 59.6% with some degree of infestation (13.5% high infestation levels and finally “other hosts” which had 51.1% with some level of infestation (11.5% high infestation levels. This study is the first detailed mapping of C. multicicatrices on the island of San Andrés which will become the basis for future work on the population dynamics of the fluted scale and its distribution on the island.

Urban tree growth modeling

Science.gov (United States)

E. Gregory McPherson; Paula J. Peper

2012-01-01

This paper describes three long-term tree growth studies conducted to evaluate tree performance because repeated measurements of the same trees produce critical data for growth model calibration and validation. Several empirical and process-based approaches to modeling tree growth are reviewed. Modeling is more advanced in the fields of forestry and...

Seasonal pattern of infestation by the carob moth Ectomyelois ceratoniae in pomegranate cultivars

NARCIS (Netherlands)

Hosseini, S.A.; Goldansaz, S.H.; Fotoukkiaii, S.M.; Menken, S.B.J.; Groot, A.T.

2017-01-01

Pomegranate (Punica granatum L.) orchards in the Middle East are typically composed of a mix of different cultivars in which variation in fruit infestation by carob moth Ectomyelois ceratoniae (Zeller) (Lepidoptera: Pyralidae) has been observed. However, seasonal variation in infestation and

Prevalence and associated risk factors for bovine tick infestation in two districts of lower Punjab, Pakistan.

Science.gov (United States)

Sajid, Muhammad Sohail; Iqbal, Zafar; Khan, Muhammad Nisar; Muhammad, Ghulam; Khan, Muhammad Kasib

2009-12-01

Bovine tick infestation is still a serious nuisance to livestock and the dairy industry of Pakistan. The current paper reports the prevalence and associated risk factors for bovine tick infestation in the districts Layyah and Muzaffargarh of lower Punjab, Pakistan. A questionnaire-based survey was conducted to identify and to quantify variation in the prevalence of bovine tick infestation with respect to host (age, species, sex, and breed) and environmental (geographical area and climate) determinants. Multiple stage cluster random sampling was used and 3500 cattle and buffaloes from the two districts were selected. Prevalence of bovine tick infestation was significantly higher (OR=1.95; p2025; 47.3%). Hyalomma anatolicum anatolicum was the major tick species (33.5%; 1173/3500), followed by Rhipicephalus sanguineus (13%; 456/3500). The highest monthly prevalence in both the districts was found in July. Ticks were not found in Layyah from November to March and in Muzaffargarh from December to March. The average number of ticks was proportional to the prevalence of infestation. Also, tick infestation in a 7cmx7cm dewlap of the animal was proportional to that of the rest of body. Prevalence of tick infestation was associated (p<0.05) with district, host species and breed. In cattle, prevalence of tick infestation was associated (p<0.05) with age and sex of host. The results of this study provide better understanding of disease epidemiology in the study districts, which will help for planning of control strategies.

Exotic plant infestation is associated with decreased modularity and increased numbers of connectors in mixed-grass prairie pollination networks

Science.gov (United States)

Larson, Diane L.; Rabie, Paul A.; Droege, Sam; Larson, Jennifer L.; Haar, Milton

2016-01-01

The majority of pollinating insects are generalists whose lifetimes overlap flowering periods of many potentially suitable plant species. Such generality is instrumental in allowing exotic plant species to invade pollination networks. The particulars of how existing networks change in response to an invasive plant over the course of its phenology are not well characterized, but may shed light on the probability of long-term effects on plant-pollinator interactions and the stability of network structure. Here we describe changes in network topology and modular structure of infested and non-infested networks during the flowering season of the generalist non-native flowering plant, Cirsium arvense in mixed-grass prairie at Badlands National Park, South Dakota, USA. Objectives were to compare network-level effects of infestation as they propagate over the season in infested and non-infested (with respect to C. arvense) networks. We characterized plant-pollinator networks on 5 non-infested and 7 infested 1-ha plots during 4 sample periods that collectively covered the length of C. arvense flowering period. Two other abundantly-flowering invasive plants were present during this time: Melilotus officinalis had highly variable floral abundance in both C. arvense-infested and non-infested plots andConvolvulus arvensis, which occurred almost exclusively in infested plots and peaked early in the season. Modularity, including roles of individual species, and network topology were assessed for each sample period as well as in pooled infested and non-infested networks. Differences in modularity and network metrics between infested and non-infested networks were limited to the third and fourth sample periods, during flower senescence of C. arvenseand the other invasive species; generality of pollinators rose concurrently, suggesting rewiring of the network and a lag effect of earlier floral abundance. Modularity was lower and number of connectors higher in infested

Expression and Activity of Lysozyme in Apis Mellifera Carnica Brood Infested with Varroa Destructor

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Zaobidna Ewa A.

2017-12-01

Full Text Available Varroa destructor is a parasitic mite that attacks the honey bee, and previous studies have suggested that parasitosis caused by this mite is accompanied by immunosuppresion in the host. In this study, the effect of mite infestation on the expression of the lysozyme-1 (lys-1 gene and lysozyme activity in Apis mellifera carnica was determined. The experiment was carried out on the five developmental stages of honey bee workers and drones. Developmental and gender-related differences in gene expression and lysozyme activity were observed in a Varroa destructor-infested brood. The relative expression of the lys-1 gene increased in a infested worker brood and decreased in a drone brood except for P3 pupae. In the final stage of development, the lys-1 gene expression was significantly lower in infested newly emerged workers and drones. Changes in the relative expression of the lys-1 gene in infested individuals was poorly manifested at the level of enzyme activity, whereas at the two final stages of development (P5 and I there was a positive correlation between relative lys-1 expression and lysozyme activity in infested bees of both genders (r=0.988, r=0.999, respectively. The results of this study indicate that V. destructor influences the lysozyme-linked immune response in bees.

Parasitic infestation in appendicitis. A retrospective analysis of 660 patients and brief literature review

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Eren Altun

2017-03-01

Full Text Available Objectives: To investigate the incidence of parasitic infestations and inflammation accompanying parasitosis in a series of appendectomy cases. Methods: Six-hundred-sixty patients who had undergone appendectomy in Bingöl State Hospital, Bingol, Turkey with the preliminary diagnosis of appendicitis between January 2012 and February 2015 were included in this retrospective study. They were retrospectively evaluated in terms of age, gender and pathological findings. Cases diagnosed with parasitic infestations were re-evaluated histopathologically for inflammatory response. Results: The mean age was 19.6 years, and the male/female ratio was 1.8. When evaluated in terms of histopathological diagnoses, 573 (86.8% were diagnosed as acute appendicitis, and parasitic infestation was identified in 12 (1.8%. Among cases with parasitic infestation, Enterobius vermicularis was identified in 9 (75% and Taenia in 3 (25% cases. Of cases with Enterobius vermicularis, 4 (44.4% had lymphoid hyperplasia, 1 (11.1% had normal-structured appendix vermiformis, and 4 (44.4% had findings of acute appendicitis. All cases with taeniasis had an inflammatory response: acute appendicitis was identified in 2 (66% and acute gangrenous appendicitis in 1 (33% of them. Conclusion: Parasitic infestations are among the probable causes in appendicitis etiology and should be kept in mind during differential diagnosis. However, whether every parasitic infestation leads to appendiceal inflammatory response is controversial.

Farmers experience on Blue Gum Chalcid, Leptocybe invasa, Infestation on Eucalyptus Species in East Africa

International Nuclear Information System (INIS)

Nyeko, P; Mutitu, K.E; Otieno, B; Oeba, V; Day, R.K

2007-01-01

Understanding indigenous knowledge and practices is important in facilitating the development and introduction of pest management technologies that meet farmers aspirations. The apper documents farmer's knowledge, perceptions and control practices of gall-forming wasps, leptocybe invasa Fisher and LaSalle in Uganda and Kenya with the aim of developing integrated management of the pest. Although the vast majority of farmeres interviewed had observed that symptoms of L. invasa infestation on Eucalyptus, very few of them were aware of causative agent. They reported the infestation as causing reduced growth rate, tree deformation and mortality. However farmers did not attempt to control the infeatation because they did not know suitable control methods and/or the casuse. Less than 20% of the farmers had recieved advice on L. invavsa, suggesting poor flow of tree pest information to farmers. Even after observing severe L. invasa, most farmers interviewed still wanted to plant Eucalyptus and they saw trees as source of several products and services, especially firewood and construction materials. As plantation forestry is developed and promoted, there is a need to integrate farmers' knowledge about tree pests into the development processes in order to improve their management practices

Host Status of Five Weed Species and Their Effects on Pratylenchus zeae Infestation of Maize.

Science.gov (United States)

Jordaan, E M; De Waele, D

1988-10-01

The host suitability of five of the most common weed species occurring in maize (Zea mays L.) fields in South Africa to Pratylenchus zeae was tested. Based on the number of nematodes per root unit, mealie crotalaria (Crotalaria sphaerocarpa) was a good host; goose grass (Eleusine indica), common pigweed (Amaranthus hybridus), and thorn apple (Datura stramonium) were moderate hosts; and khaki weed (Tagetes minuta) was a poor host. Only the root residues of khaki weed suppressed the P. zeae infestation of subsequently grown maize. When goose grass, khaki weed, and mealie crotalaria were grown in association with maize in soil infested with P. zeae, goose grass and khaki weed severely suppressed maize root development; this resulted in a low number of nematodes per maize root system and a high number of nematodes per maize root unit. Mealie crotalaria did not restrict maize root growth and did not affect nematode densities per maize root system or maize root unit. Special attention should be given to the control of mealie crotalaria, which is a good host for P. zeae, and goose grass, which, in addition to its ability to compete with maize, is also a suitable host for P. zeae.

Impact of pine needle leachates from a mountain pine beetle infested watershed on groundwater geochemistry

Science.gov (United States)

Pryhoda, M.; Sitchler, A.; Dickenson, E.

2013-12-01

The mountain pine beetle (MPB) epidemic in the northwestern United States is a recent indicator of climate change; having an impact on the lodgepole pine forest ecosystem productivity. Pine needle color can be used to predict the stage of a MPB infestation, as they change color from a healthy green, to red, to gray as the tree dies. Physical processes including precipitation and snowfall can cause leaching of pine needles in all infestation stages. Understanding the evolution of leachate chemistry through the stages of MPB infestation will allow for better prediction of the impact of MPBs on groundwater geochemistry, including a potential increase in soil metal mobilization and potential increases in disinfection byproduct precursor compounds. This study uses batch experiments to determine the leachate chemistry of pine needles from trees in four stages of MPB infestation from Summit County, CO, a watershed currently experiencing the MPB epidemic. Each stage of pine needles undergoes four subsequent leach periods in temperature-controlled DI water. The subsequent leaching method adds to the experiment by determining how leachate chemistry of each stage changes in relation to contact time with water. The leachate is analyzed for total organic carbon. Individual organic compounds present in the leachate are analyzed by UV absorption spectra, fluorescence spectrometry, high-pressure liquid chromatography for organic acid analysis, and size exclusion chromatography. Leachate chemistry results will be used to create a numerical model simulating reactions of the leachate with soil as it flows through to groundwater during precipitation and snowfall events.

Multiple ectoparasites infest Microcebus griseorufus at Beza ...

African Journals Online (AJOL)

Multiple ectoparasites infest Microcebus griseorufus at Beza Mahafaly Special Reserve, Madagascar. IA Rodriguez, E Rasoazanabary, LR Godfrey. Abstract. The mouse lemur Microcebus griseorufus at the Beza Mahafaly Special Reserve and general vicinity in southwestern Madagascar were surveyed for ectoparasites as ...

Preventive efficacy of NexGard Spectra® against Dipylidium caninum infection in dogs using a natural flea (Ctenocephalides felis) infestation model.

Science.gov (United States)

Beugnet, Frédéric; Meyer, Leon; Fourie, Josephus; Larsen, Diane

2017-01-01

The efficacy of a monthly oral endectocide product, NexGard Spectra ® (Merial), a combination of afoxolaner and milbemycin oxime, was evaluated in a flea (Ctenocephalides felis) challenge model for the prevention of Dipylidium caninum tapeworm infection in dogs. The efficacy of treatment with NexGard Spectra ® was assessed in 10 dogs following weekly flea infestation with metacestode naturally infected fleas and compared with that in 10 untreated control dogs. The 100 fleas deposited weekly on each dog were not removed until Day 35, allowing enough time for their ingestion. The microscopical analysis of 30 fleas from the flea batches before each weekly challenge demonstrated that 10-33% of the fleas were infected by D. caninum cysticercoid larvae. The arithmetic mean flea count recorded was 47.7 for the 10 untreated dogs and 0 for the 10 treated dogs at Day 35. Based on the daily collection of expelled D. caninum proglottids by dogs during the 70 days of the study, 70% (7/10) of the control dogs and 0% (0/10) of the treated dogs were infected with D. caninum (p caninum infestation. No treatment-related adverse events were observed in dogs during this study. © F. Beugnet et al., published by EDP Sciences, 2017.

The response of sweet basil (Ocimum basilicum L. to the application of growth stimulators and forecrops

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Cezary A. Kwiatkowski

2012-12-01

Full Text Available A field experiment in growing sweet basil was carried out in the period 2008-2010 in Fajsławice (Lublin region, on podzolic soil. The study evaluated the biometric traits of the plants, yield, the qualitative parameters of herbal raw material and weed infestation of the crop in dependence on growth simulators (Asahi SL, Bio-algeen, Titanit and the forecrop (winter wheat or spring barley + white mustard cover crop. Plots without foliar application of the growth stimulators were the control treatment. Tillage, mineral NPK fertilization as well as mechanical and chemical weed control were typical for this plant species and consistent with the recommendations for herbal plant protection. A hypothesis was made that the application of growth stimulators would have a positive effect on basil productivity, raw material quality and weed infestation of the basil crop. It was also assumed that the phytosanitary and fertilizing effects of the cover crop would result in higher and qualitatively better yield compared to the cereal forecrop alone (winter wheat. The best quantitative parameters of sweet basil raw material and the highest reduction in air-dry weight of weeds in the crop were observed after the application of the growth stimulators. The forecrop - spring barley + a white mustard cover crop that is ploughed in - also had a beneficial effect on yield and weed infestation of the plant in question. The traditional crop protection method used in the basil crop, without the application of the growth stimulators, resulted in a lower plant height and a smaller number of shoots per plant. This caused higher weed infestation of the crop and a decrease in yield. The positive side of the non-application of growth stimulators was a better chemical composition of basil raw material. Asahi SL and Tytanit yielded the best growth and productivity of the basil plants.

Infestation of the human kidney with Dioctophyma renale.

Science.gov (United States)

Ignjatovic, Ivan; Stojkovic, Ivica; Kutlesic, Cedo; Tasic, Suzana

2003-01-01

Human infestation with Dioctophyma renale is presented. Clinical signs and diagnostic findings are unspecific. They are discussed and a conservative therapeutic approach is suggested. Copyright 2003 S. Karger AG, Basel

Ectoparasitic infestation of dogs in Bendel State, Nigeria.

Science.gov (United States)

Ugochukwu, E I; Nnadozie, C C

1985-12-01

An investigation into ectoparasitic infestation of different breeds of dogs presented to four veterinary clinics in Benin, Sapele and Auchi in Bendel State of Nigeria during the period January 1983 to December 1983 is presented. Of a total of 820 dogs examined for ectoparasites 246 (30.00%) were infected by ticks, 226 (27.56%) by lice, 212 (25.85%) by fleas and 109 (13.29%) by mites. The species of ectoparasites identified and their prevalence rates were Rhipicephalus sanguineus (19.5%), Otobius megnini (10.48%), Ctenocephalides canis (25.85%), Demodex canis (13.29%). Common clinical symptoms evinced in this species include scratching, licking, irritation, restlessness, alopecia, otitis externa and dermatitis. Some aspects of epidemiology of canine ectoparasitic infestation are discussed.

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

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Durand R.

2012-11-01

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

Infestation of Raoiella indica Hirst (Trombidiformes: Tenuipalpidae) on Host Plants of High Socio-Economic Importance for Tropical America.

Science.gov (United States)

Otero-Colina, G; González-Gómez, R; Martínez-Bolaños, L; Otero-Prevost, L G; López-Buenfil, J A; Escobedo-Graciamedrano, R M

2016-06-01

The mite Raoiella indica Hirst was recently introduced into America, where it has shown amazing ability to disseminate and broaden its range of hosts. An experiment was conducted in Cancún, Mexico, to determine infestation levels of this mite on plants recorded as hosts: coconut palm (Cocos nucifera) of cultivars Pacific Tall and Malayan Dwarf, oil palm (Elaeis guineensis) hybrids Deli x Ghana and Deli x Nigeria, Dwarf Giant banana (Musa acuminata, AAA subgroup Cavendish), Horn plantain (M. acuminata x Musa balbisiana, AAB subgroup Plantain), lobster claw (Heliconia bihai), and red ginger (Alpinia purpurata). Nursery plants of these host species or cultivars were artificially infested with R. indica in February 2011. In the four replications of 10 plants, each plant was infested with 200 R. indica specimens, and the numbers of infesting mites were recorded for 6 months. A maximum of 18,000 specimens per plant were observed on coconut Pacific Tall and Malayan Dwarf, followed by lobster claw, with a maximum of 1000 specimens per plant. Infestations were minimal for the remaining plants. Mite numbers on all plants declined naturally during the rainy season. All plant materials sustained overlapping mite generations, indicating that they are true hosts. Complementarily, infestation level was determined in backyard bananas and plantains. Correlations of infestation with plant height, distance from coconuts, and exposure to direct sunlight were estimated. Both bananas and plantains were infested by R. indica even when situated far from infested coconut palms. A Spearman correlation was found between infestation and plant height, although it was significant only for Silk plantain.

Population growth and within-plant distribution of the striped mealybug Ferrisia virgata (Cockerell (Hemiptera, Pseudococcidae on cotton

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Martin D. Oliveira

2014-03-01

Full Text Available Population growth and within-plant distribution of the striped mealybug Ferrisia virgata (Cockerell (Hemiptera, Pseudococcidae on cotton. The striped mealybug, Ferrisia virgata (Cockerell (Hemiptera, Pseudococcidae, is a widely distributed and polyphagous pest species, which naturally occurs on cotton plants in Brazil. This study evaluated the establishment and population growth as well as the within-plant distribution of F. virgata on four cotton cultivars: CNPA 7H (white fibers, BRS Verde, BRS Safira, and BRS Rubi (colored fibers. The experiment was conducted in a complete randomized design with four treatments (cultivars and 18 replications of each. Thus, cotton plants of each cultivar were infested with 100 newly hatched nymphs of F. virgata. The number of adult female mealybugs and the total number of mealybugs per plant were quantified, respectively, at 25 and 50 days after infestation. The developmental and pre-reproductive periods were also determined. Furthermore, we verified the distribution of F. virgata on the plant parts at 25 and 50 days after infestation. Ferrisia virgata showed similar growth of 412-fold in the four cotton cultivars studied. Also, the nymphs were spread on infested leaves; the secondgeneration nymphs were spread and established in all plant parts. Our results characterize F. virgata as having much potential as an important cotton pest in Brazil.

A previously unidentified Chorioptes species infesting outer ear canals of moose (Alces alces: characterization of the mite and the pathology of infestation

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Mattsson Roland

2007-09-01

Full Text Available Abstract Background During the past decade, Chorioptes mites occupying the outer ear canals have been a common finding at routine necropsies of moose (Alces alces in Sweden, but neither the taxonomy of the mites nor lesions from the infestation have been investigated. In this study, the mites are characterized by morphological and molecular techniques, and the histopathology of the skin of the outer ear canal is described. Methods External auditory meatuses from 53 necropsied moose were examined for the presence of Chorioptes, and samples from outer ear canals were taken for histopathological and microbiological examination. A proportion of the mites from each moose was identified to species. The DNA was extracted from mites from three moose, and their ITS-2 sequences were determined; these sequences were compared phylogenetically to sequences from other Chorioptes taxa. Results Chorioptes mites were found in 43 (81% of the 53 moose. The mites had morphological and genetic characteristics distinct from those of C. texanus and C. bovis, the two species generally accepted within the genus. Morphology also did not argue for a diagnosis as C. crewei, C. mydaus or C. panda. On histopathology, lesions were characterized by a hyperplastic perivascular to interstitial dermatitis with epidermal hyperkeratosis and crust formation. Dermal inflammatory infiltrates were composed of mixed T- and B-lymphocytes, plasma cells and macrophages, whereas eosinophils were notably uncommon. Staphylococcus aureus was grown from the infested epidermis of five of 14 examined moose. Conclusion Chorioptes mite infestation was frequently detected in the outer ear canals of moose in Sweden. The mites were evidently pathogenic, being associated with inflammatory lesions of the external auditory meatus. Our studies indicate infestations with a previously undescribed Chorioptes species.

Hematology and serum biochemistry in debilitated, free-ranging raccoon dogs (Nyctereutes procyonoides) infested with sarcoptic mange.

Science.gov (United States)

Kido, Nobuhide; Kamegaya, Chihiro; Omiya, Tomoko; Wada, Yuko; Takahashi, Maya; Yamamoto, Yasuhiko

2011-12-01

Frequent outbreaks of Sarcoptes scabiei infestation in raccoon dogs (Nyctereutes procyonoides) have been reported in Japan. Although many raccoon dogs are brought to Kanazawa Zoological Garden (Yokohama, Kanagawa, Japan) because of S. scabiei infestation and debilitation, some of them die of asthenia. The clinical status of severely debilitated raccoon dogs must be determined to save their lives. In this study, we compared hematological and serum biochemical values between severely debilitated and nondebilitated raccoon dogs infested with S. scabiei. The total protein, albumin, glucose, and calcium values of debilitated raccoon dogs were significantly lower than those of nondebilitated raccoon dogs. On the other hand, debilitated raccoon dogs had significantly higher aspartate aminotransferase, total bilirubin, blood urea nitrogen, sodium, chloride, and phosphorus values than did nondebilitated raccoon dogs. The increase in the blood urea nitrogen value was particularly dramatic. The present study revealed that debilitated raccoon dogs infested with S. scabiei exhibited abnormal hematological values compared with nondebilitated raccoon dogs infested with S. scabiei. Clinically, the raccoon dogs developed malnutrition and sepsis if the mange infestation was untreated. Moreover, dehydration associated with appetite loss may have resulted in insufficient renal perfusion. These findings suggest that chronic S. scabiei infestations debilitated the raccoon dogs and resulted in physiological changes that were detected with hematological and serum biochemical tests. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Efficacy of the d-phenothrin/pyriproxyfen association against mites in naturally co-infested rabbits

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Julio I. Fernandes

2013-05-01

Full Text Available The aim of the present study was to evaluate the efficacy of the d-phenothrin/pyriproxyfen association against Psoroptes ovis, Cheyletiella parasitivorax, and Leporacarus gibbus infestations in naturally co-infested rabbits. Twenty crossbreed (New Zealand White x California rabbits concurrently infested by the three mite species were randomly divided in two groups. All rabbits presented with hyperemia, erythema and formation of crusts in the ear canals caused by P. ovis. Infestations by both C. parasitivorax and L. gibbus were considered asymptomatic in all animals.Ten animals were treated with a 4.4% d-phenothrin and 0.148% pyriproxyfen spray formulation until have their body surface uniformly sprayed, including external ear canals. The other ten rabbits remained untreated, serving as control group. Observations were done on days +7, +14, +21, +28, and +35 post-treatment. The d-phenothrin/pyriproxyfen association showed 100% efficacy against the three mite species and was responsible for the remission of psoroptic mange lesions on treated animals. No signs of intoxication were observed. The results indicate that d-phenothrin/pyriproxyfen spray formulation in a single application is an effective and clinically safe option for the control of different mite infestations in rabbits.

Delusional infestation is typically comorbid with other psychiatric diagnoses: review of 54 patients receiving psychiatric evaluation at Mayo Clinic.

Science.gov (United States)

Hylwa, Sara A; Foster, Ashley A; Bury, Jessica E; Davis, Mark D P; Pittelkow, Mark R; Bostwick, J Michael

2012-01-01

Delusional infestation, which encompasses both delusions of parasitosis and delusions of infestation with inanimate objects (sometimes called Morgellons disease), has been said to represent a distinct and encapsulated delusion, that is, a stand-alone diagnosis. Anecdotally, we have observed that patients with delusional infestation often have one or more psychiatric comorbid conditions and that delusional infestation should not be regarded as a stand-alone diagnosis. The purpose of this study was to identify whether patients with delusional infestation have psychiatric comorbid conditions. We therefore identified patients who had been formally evaluated in the Department of Psychiatry during their visit to Mayo Clinic. We retrospectively searched for and reviewed the cases of all patients with delusional infestation seen from 2001 through 2007 at Mayo Clinic, Rochester, Minnesota, and who underwent psychiatric evaluation. The diagnoses resulting from psychiatric evaluation were analyzed. During the 7-year study period, 109 patients seen for delusional infestation at Mayo Clinic were referred to the Department of Psychiatry, 54 (50%) of whom actually followed through with psychiatric consultation. Of these 54 patients, 40 (74%) received additional active psychiatric diagnoses; 14 patients (26%) had delusional infestation alone. Abnormal personality traits were rarely documented. Most patients with delusional infestation have multiple coexisting or underlying psychiatric disorders. Therefore, evaluation by a psychiatrist, when possible, is advised for all patients with delusional infestation. Copyright © 2012 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.

The influence of intercrop plants and the date of their ploughing-in on weed infestation of root chicory (Cichorium intybus L. var. sativum (Bisch. Janch.

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Marzena Błażewicz-Woźniak

2012-12-01

Full Text Available The field experiment was carried out in 2006-2008 in the Felin Experimental Farm (University of Life Sciences in Lublin on podzolic soil developed from dusty medium loam. Root chicory (Cichorium intybus L. var. sativum (Bisch. Janch. cv. Polanowicka was involved in the experiment. The experimental factors were 3 species of intercrop plants: common vetch (Vicia sativa, phacelia (Phacelia tanacetifolia, oat (Avena sativa and 2 dates of ploughing-in: pre-winter and spring. In total, 26 taxons characteristic for vegetable plantations were identified in chicory weed infestation. Monocarpic species dominated, among which Senecio vulgaris, Chenopodium album, Lamium amplexicaule, Galinsoga ciliata, and Capsella bursa-pastoris were predominant. The date of ploughing-in did not significantly affect the status and size of weed infestation of chicory plots. Short-lived species occurred after pre-winter ploughing-in, while perennial - after spring ploughing-in. The application of intercrops significantly reduced chicory weed infestation as compared to the cultivation with no intercrop. The ploughing-in of Avena sativa biomass appeared to be the most efficient. The intercrop plants reduced the occurrence of Senecio vulgaris and Capsella bursa-pastoris which were the most numerous in the treatment without intercrops. Biomass of Vicia sativa favored the growth of Chenopodium album and Lamium amplexicaule. The secondary weed infestation did not depend on agrotechnical factors applied during the experiment.

Laser diagnostic technology for early detection of pathogen infestation in orange fruits

International Nuclear Information System (INIS)

Giubileo, Gianfranco; Lai, Antonella; Piccinelli, Delinda; Puiu, Adriana

2010-01-01

Due to an increased expectation of food products that respect high quality and safety standards, there is a need for the growth of accurate, fast, objective and non-destructive technologies for quality determination of food and agricultural products. For this purpose, a diagnostic system based on laser photoacoustic spectroscopy (LPAS) was developed at ENEA Frascati Molecular Spectroscopy Laboratory (Italy). In the design of the photoacoustic detector, particular emphasis was placed in attaining a high sensitivity in detecting ethylene (ET) down to sub-parts per billion level (minimum detectable concentration 0.2 ppb). This was required due to the necessity to monitor and follow up ET production at a single fruit scale. ET is normally synthesised in very low amounts by healthy citrus fruits; however stress conditions such as pathogen attack may induce a substantial increase in the synthesised ET. In the present paper, the comparison between the ET emitted by healthy oranges (Citrus sinensis L. Osbeck) cv Navel and by Phytophthora citrophthora infested Navel orange fruits are reported. The obtained results show a well evident increase in ET emission from the infested fruit with respect to the healthy one, even 24 h after the inoculation with the pathogen; at that time the tissue necrosis was not yet visible, and the fruit was also not yet damaged. The possibility to perform a real time non-destructive detection of ET traces makes the LPAS a powerful tool for monitoring the healthy state of the citrus fruits.

Laser diagnostic technology for early detection of pathogen infestation in orange fruits

Science.gov (United States)

Giubileo, Gianfranco; Lai, Antonella; Piccinelli, Delinda; Puiu, Adriana

2010-11-01

Due to an increased expectation of food products that respect high quality and safety standards, there is a need for the growth of accurate, fast, objective and non-destructive technologies for quality determination of food and agricultural products. For this purpose, a diagnostic system based on laser photoacoustic spectroscopy (LPAS) was developed at ENEA Frascati Molecular Spectroscopy Laboratory (Italy). In the design of the photoacoustic detector, particular emphasis was placed in attaining a high sensitivity in detecting ethylene (ET) down to sub-parts per billion level (minimum detectable concentration 0.2 ppb). This was required due to the necessity to monitor and follow up ET production at a single fruit scale. ET is normally synthesised in very low amounts by healthy citrus fruits; however stress conditions such as pathogen attack may induce a substantial increase in the synthesised ET. In the present paper, the comparison between the ET emitted by healthy oranges ( Citrus sinensis L. Osbeck) cv Navel and by Phytophthora citrophthora infested Navel orange fruits are reported. The obtained results show a well evident increase in ET emission from the infested fruit with respect to the healthy one, even 24 h after the inoculation with the pathogen; at that time the tissue necrosis was not yet visible, and the fruit was also not yet damaged. The possibility to perform a real time non-destructive detection of ET traces makes the LPAS a powerful tool for monitoring the healthy state of the citrus fruits.

Laser diagnostic technology for early detection of pathogen infestation in orange fruits

Energy Technology Data Exchange (ETDEWEB)

Giubileo, Gianfranco, E-mail: gianfranco.giubileo@frascati.enea.i [ENEA Frascati, Via E. Fermi 45, 00044 (Italy); Lai, Antonella; Piccinelli, Delinda [ENEA Frascati, Via E. Fermi 45, 00044 (Italy); Puiu, Adriana [Tor Vergata University of Rome, Faculty of Engineering, Via del Politecnico 1, 00133 Rome (Italy)

2010-11-11

Due to an increased expectation of food products that respect high quality and safety standards, there is a need for the growth of accurate, fast, objective and non-destructive technologies for quality determination of food and agricultural products. For this purpose, a diagnostic system based on laser photoacoustic spectroscopy (LPAS) was developed at ENEA Frascati Molecular Spectroscopy Laboratory (Italy). In the design of the photoacoustic detector, particular emphasis was placed in attaining a high sensitivity in detecting ethylene (ET) down to sub-parts per billion level (minimum detectable concentration 0.2 ppb). This was required due to the necessity to monitor and follow up ET production at a single fruit scale. ET is normally synthesised in very low amounts by healthy citrus fruits; however stress conditions such as pathogen attack may induce a substantial increase in the synthesised ET. In the present paper, the comparison between the ET emitted by healthy oranges (Citrus sinensis L. Osbeck) cv Navel and by Phytophthora citrophthora infested Navel orange fruits are reported. The obtained results show a well evident increase in ET emission from the infested fruit with respect to the healthy one, even 24 h after the inoculation with the pathogen; at that time the tissue necrosis was not yet visible, and the fruit was also not yet damaged. The possibility to perform a real time non-destructive detection of ET traces makes the LPAS a powerful tool for monitoring the healthy state of the citrus fruits.

Infestation of froghopper nymphs changes the amounts of total phenolics in sugarcane

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Silva Rafael José Navas da

2005-01-01

Full Text Available The increased rate of sugarcane harvest without previous burn has provided a very favorable environment to the froghopper Mahanarva fimbriolata (Stal, 1854, with high moisture and low temperature variation. Few works have studied the response of sugarcane to this pest, so little is known about resistant cultivars. Plant phenolics are widely studied compounds because of their known antiherbivore effect. This research aims to determine if the attack of M. fimbriolata nymphs stimulates the accumulation of total phenolics in sugarcane. The experiment was carried out in greenhouse and arranged in completely randomized design, in a 3 X 2 X 4 factorial with three replications. Second instar nymphs of M. fimbriolata were infested at the following rates: control, 2-4 and 4-8 nymphs per pot (first-second infestations, respectively. Pots were covered with nylon net and monitored daily to isolate the effect of leaf sucking adults. Leaf and root samples were collected and kept frozen in liquid nitrogen until analyses. Infested plants showed higher levels of phenolics in both root and leaf tissues. In roots, the cultivar SP80-1816 accumulated more phenolic compounds in response to the infestation of M. fimbriolata. On the other hand, higher levels were found in leaves and roots of control plants of SP86-42, which might be an indication of a non-preference mechanism. The increase of total phenolics in sugarcane infested with root-sucking froghopper nymphs does not seem to be useful to detect the resistance to this pest.

Patterns of Aedes aegypti (Diptera: Culicidae) infestation and container productivity measured using pupal and Stegomyia indices in northern Argentina.

Science.gov (United States)

Garelli, F M; Espinosa, M O; Weinberg, D; Coto, H D; Gaspe, M S; Gürtler, R E

2009-09-01

A citywide control program of Aedes aegypti (L.) (Diptera: Culicidae) mainly based on the use of larvicides reduced infestations but failed to achieve the desired target levels in Clorinda, northeastern Argentina, over 5 yr of interventions. To understand the underlying causes of persistent infestations and to develop new control tactics adapted to the local context, we conducted two pupal surveys in a large neighborhood with approximately 2,500 houses and recorded several variables for every container inspected in fall and spring 2007. In total, 4,076 lots and 4,267 containers were inspected over both surveys, and 8,391 Ae. aegypti pupae were collected. Large tanks used for potable water storage were the most abundant and the most productive type of container, accounting for 65-84% of all the pupae collected. Therefore, large tanks were key containers and candidates for improved targeted interventions. Multivariate analysis showed that containers located in the yard, at low sun exposure, unlidded, filled with rain water, and holding polluted water were all more likely to be infested by larvae or pupae. When only infested containers were considered, productivity of pupae was most closely associated with large tanks and rain water. A stochastic simulation model was developed to calculate the expected correlations between pupal and Stegomyia indices according to the characteristics of the distribution of larvae and pupae per container and the spatial scale at which the indices were computed. The correlation between pupal and Stegomyia indices is expected to increase as infestation levels decline.

Evaluation of the relationship between androgenetic alopecia and demodex infestation

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Zari Javidi

2008-01-01

Full Text Available Introduction: Androgenetic alopecia (AGA is one of the most common dermatologic disorders with a multifactorial etiology. Inflammatory activators such as Demodex infestation may play a role in the pathogenesis of some cases of androgenetic alopecia that do not respond to common treatments such as minoxidil and finasteride. The goal of this study is to evaluate the relationship between Demodex infestation and AGA. Materials and Methods: In this case-control study, 41 patients with AGA referred to the Dermatology Clinic of Imam Reza Hospital and 33 healthy individuals were evaluated as control. All of them were between 20 and 40 years old men. In order to identify Demodex infestation they were referred to the Parasitology laboratory. Results: Demodex was detected in 19.5% of patients and 15.2% of controls; therefore, there was no significant relationship between them statistically ( P = 0.0787. Most of patients (85.4% had greasy hair. The most common pattern of baldness was II degree in Hamilton scale. Conclusion: There is no relation between AGA and Demodex.

Residual infestation and recolonization during urban Triatoma infestans Bug Control Campaign, Peru.

Science.gov (United States)

Barbu, Corentin M; Buttenheim, Alison M; Pumahuanca, Maria-Luz Hancco; Calderón, Javier E Quintanilla; Salazar, Renzo; Carrión, Malwina; Rospigliossi, Andy Catacora; Chavez, Fernando S Malaga; Alvarez, Karina Oppe; Cornejo del Carpio, Juan; Náquira, César; Levy, Michael Z

2014-12-01

Chagas disease vector control campaigns are being conducted in Latin America, but little is known about medium-term or long-term effectiveness of these efforts, especially in urban areas. After analyzing entomologic data for 56,491 households during the treatment phase of a Triatoma infestans bug control campaign in Arequipa, Peru, during 2003-2011, we estimated that 97.1% of residual infestations are attributable to untreated households. Multivariate models for the surveillance phase of the campaign obtained during 2009-2012 confirm that nonparticipation in the initial treatment phase is a major risk factor (odds ratio [OR] 21.5, 95% CI 3.35-138). Infestation during surveillance also increased over time (OR 1.55, 95% CI 1.15-2.09 per year). In addition, we observed a negative interaction between nonparticipation and time (OR 0.73, 95% CI 0.53-0.99), suggesting that recolonization by vectors progressively dilutes risk associated with nonparticipation. Although the treatment phase was effective, recolonization in untreated households threatens the long-term success of vector control.

Lévy-based growth models

DEFF Research Database (Denmark)

Jónsdóttir, Kristjana Ýr; Schmiegel, Jürgen; Jensen, Eva Bjørn Vedel

2008-01-01

In the present paper, we give a condensed review, for the nonspecialist reader, of a new modelling framework for spatio-temporal processes, based on Lévy theory. We show the potential of the approach in stochastic geometry and spatial statistics by studying Lévy-based growth modelling of planar o...... objects. The growth models considered are spatio-temporal stochastic processes on the circle. As a by product, flexible new models for space–time covariance functions on the circle are provided. An application of the Lévy-based growth models to tumour growth is discussed....

Norwegian honey bees surviving Varroa destructor mite infestations by means of natural selection.

Science.gov (United States)

Oddie, Melissa A Y; Dahle, Bjørn; Neumann, Peter

2017-01-01

Managed, feral and wild populations of European honey bee subspecies, Apis mellifera , are currently facing severe colony losses globally. There is consensus that the ectoparasitic mite Varroa destructor , that switched hosts from the Eastern honey bee Apis cerana to the Western honey bee A. mellifera , is a key factor driving these losses. For >20 years, breeding efforts have not produced European honey bee colonies that can survive infestations without the need for mite control. However, at least three populations of European honey bees have developed this ability by means of natural selection and have been surviving for >10 years without mite treatments. Reduced mite reproductive success has been suggested as a key factor explaining this natural survival. Here, we report a managed A. mellifera population in Norway, that has been naturally surviving consistent V. destructor infestations for >17 years. Surviving colonies and local susceptible controls were evaluated for mite infestation levels, mite reproductive success and two potential mechanisms explaining colony survival: grooming of adult worker bees and Varroa Sensitive Hygiene (VSH): adult workers specifically detecting and removing mite-infested brood. Mite infestation levels were significantly lower in surviving colonies and mite reproductive success was reduced by 30% when compared to the controls. No significant differences were found between surviving and control colonies for either grooming or VSH. Our data confirm that reduced mite reproductive success seems to be a key factor for natural survival of infested A. mellifera colonies. However, neither grooming nor VSH seem to explain colony survival. Instead, other behaviors of the adult bees seem to be sufficient to hinder mite reproductive success, because brood for this experiment was taken from susceptible donor colonies only. To mitigate the global impact of V. destructor , we suggest learning more from nature, i.e., identifying the obviously

Norwegian honey bees surviving Varroa destructor mite infestations by means of natural selection

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Melissa A.Y. Oddie

2017-10-01

Full Text Available Background Managed, feral and wild populations of European honey bee subspecies, Apis mellifera, are currently facing severe colony losses globally. There is consensus that the ectoparasitic mite Varroa destructor, that switched hosts from the Eastern honey bee Apis cerana to the Western honey bee A. mellifera, is a key factor driving these losses. For >20 years, breeding efforts have not produced European honey bee colonies that can survive infestations without the need for mite control. However, at least three populations of European honey bees have developed this ability by means of natural selection and have been surviving for >10 years without mite treatments. Reduced mite reproductive success has been suggested as a key factor explaining this natural survival. Here, we report a managed A. mellifera population in Norway, that has been naturally surviving consistent V. destructor infestations for >17 years. Methods Surviving colonies and local susceptible controls were evaluated for mite infestation levels, mite reproductive success and two potential mechanisms explaining colony survival: grooming of adult worker bees and Varroa Sensitive Hygiene (VSH: adult workers specifically detecting and removing mite-infested brood. Results Mite infestation levels were significantly lower in surviving colonies and mite reproductive success was reduced by 30% when compared to the controls. No significant differences were found between surviving and control colonies for either grooming or VSH. Discussion Our data confirm that reduced mite reproductive success seems to be a key factor for natural survival of infested A. mellifera colonies. However, neither grooming nor VSH seem to explain colony survival. Instead, other behaviors of the adult bees seem to be sufficient to hinder mite reproductive success, because brood for this experiment was taken from susceptible donor colonies only. To mitigate the global impact of V. destructor, we suggest learning

Efficacy of fluralaner administered either orally or topically for the treatment of naturally acquired Sarcoptes scabiei var. canis infestation in dogs.

Science.gov (United States)

Taenzler, Janina; Liebenberg, Julian; Roepke, Rainer K A; Frénais, Régis; Heckeroth, Anja R

2016-07-07

The efficacy of fluralaner, formulated as a chewable tablet (Bravecto™) or topical solution (Bravecto™ Spot-on Solution), was evaluated against naturally acquired Sarcoptes scabiei var. canis infestation in dogs. The study was performed in privately-owned dogs naturally infested with S. scabiei var. canis. All dogs living in the same household as the infested dog were enrolled into one of 3 groups (2 fluralaner treated and 1 negative control). All dogs within one household were administered the same treatment, with one dog per household included in further observations and assessments. In total, 29 dogs confirmed positive for sarcoptic mange were included. On Day 0, all dogs in group 1 (n = 9) were treated once orally with fluralaner at a minimum dose of 25 mg/kg body weight; all dogs in group 2 (n = 11) were treated once topically with fluralaner at a dose of 25 mg/kg body weight; and dogs in group 3 (n = 9) were treated once topically with saline solution. Sarcoptes scabiei var. canis mites on each dog were counted before treatment and at 4 weeks after treatment in deep skin scrapings (~4 cm(2)) from 5 different body areas. Clinical signs of infestation (i.e. erythematous papules; casts, scales and crusts; body areas with hair loss) and pruritus were recorded at the same time points. Single oral or topical treatment with fluralaner resulted in a 100 % reduction in mite counts post-treatment (group 1: P = 0.0009 and group 2: P = 0.0011). Resolution of clinical signs at four weeks post-treatment was variable, with improvement observed for erythematous papules, casts and crusts, and pruritus. All fluralaner treated dogs showed an improvement in overall hair re-growth compared with pre-treatment observations. Fluralaner administered either orally or topically to naturally infested dogs eliminates Sarcoptes scabiei var. canis mites and improves clinical signs over a 4-week observation period.

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

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Zachary C DeVries

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

A study on Maruca vitrata infestation of Yard-long beans (Vigna unguiculata subspecies sesquipedalis

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R.C. Jayasinghe

2015-09-01

Full Text Available Globally, Maruca vitrata (Geyer is a serious yield constraint on food legumes including Yard-long bean (Vigna unguiculata subspecies sesquipedalis. However, there is a dearth of information on its damage potential, distribution and population dynamics in Yard-long beans. In the present study, the level of M. vitrata larval infestation on flowers and pods of Yard-long beans in Sri Lanka was determined with respect to three consecutive cropping seasons, Yala, Off and Maha. Results indicated that larval infestation and abundance varied with developmental stage of flowers and pods, cropping season and their combined interactive effects. Flowers of Yard-long beans were more prone to M. vitrata larval attack compared to pods. Abundance and level of infestation of M. vitrata varied with plant parts, having a ranking of flower buds (highest > open flowers > mature pods > immature pods (lowest. Peak infestation was observed six and eight weeks after planting on flowers and pods, respectively. Among the three cropping seasons, M. vitrata infestation was found to be higher during Maha and Off seasons compared to Yala. The findings of this study contribute to the identified knowledge gap regarding the field biology of an acknowledged important pest, M. vitrata, in a previously understudied crop in Sri Lanka.

Weed infestation of winter wheat (Triticum aestivum L. under the conditions of application of some retardants

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Elżbieta Harasim

2013-07-01

Full Text Available A field study was conducted in the period 2004–2007 on grey-brown podzolic soil (sandy. This study analysed the relationship between the use of stem shortening in cereals by means of retardants with the following active substances: chlormequat chloride (Antywylegacz Płynny 675 SL, trinexapac-ethyl (Moddus 250 EC, chlormequat chloride + ethephon (Cecefon 465 SL, and weed infestation. The retardants were applied at the 1st node stage (BBCH 31 – Antywylegacz Płynny 675 SL and the 2nd node stage of winter wheat (BBCH 32 – Moddus 250 EC and Cecefon 465 SL, together with the adjuvant Atpolan 80 EC (75% of SN 200 mineral oil or without the adjuvant. Winter wheat, cv. 'Muza', was grown after vetch grown for seed. The whole experiment was sprayed with the herbicides Apyros 75 WG and Starane 250 EC at the full tillering stage (BBCH 29–30. Plots where no growth regulators were used were the control treatment. Weed density and biomass showed great variation between years. In the winter wheat crop, Veronica persica, Viola arvensis, Veronica arvensis, Capsella bursa-pastoris,and Chenopodium album dominated in the dicotyledonous class, whereas Apera spica-venti, Echinochloa crus-galli,and Elymus repens were predominant among monocotyledonous plants. The level of weed infestation of the winter wheat crop, as measured by the number and air-dry weight of weeds, was significantly differentiated by years and retardants used as well as by interactions of these factors. The adjuvant Atpolan 80 EC did not have a significant effect on the above-mentioned weed infestation parameters. .

Preventive efficacy of NexGard Spectra® against Dipylidium caninum infection in dogs using a natural flea (Ctenocephalides felis infestation model

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Beugnet Frédéric

2017-01-01

Full Text Available The efficacy of a monthly oral endectocide product, NexGard Spectra® (Merial, a combination of afoxolaner and milbemycin oxime, was evaluated in a flea (Ctenocephalides felis challenge model for the prevention of Dipylidium caninum tapeworm infection in dogs. The efficacy of treatment with NexGard Spectra® was assessed in 10 dogs following weekly flea infestation with metacestode naturally infected fleas and compared with that in 10 untreated control dogs. The 100 fleas deposited weekly on each dog were not removed until Day 35, allowing enough time for their ingestion. The microscopical analysis of 30 fleas from the flea batches before each weekly challenge demonstrated that 10–33% of the fleas were infected by D. caninum cysticercoid larvae. The arithmetic mean flea count recorded was 47.7 for the 10 untreated dogs and 0 for the 10 treated dogs at Day 35. Based on the daily collection of expelled D. caninum proglottids by dogs during the 70 days of the study, 70% (7/10 of the control dogs and 0% (0/10 of the treated dogs were infected with D. caninum (p < 0.0031. Through its efficacy against fleas, NexGard Spectra® treatment provided indirect prevention of D. caninum infestation. No treatment-related adverse events were observed in dogs during this study.

Weed infestation of crops in different soils in the protective zone of Roztocze National Park. Part I. Winter and spring cereals

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Marta Ziemińska-Smyk

2013-12-01

Full Text Available The study on weed infestation of crops in different soils in the protective zone of RPN was conducted in the years 1991-1995. The characterization of weed infestation of winter and spring cereals was based on 306 phytosociological records. made with the use of Braun-Blanquet method. The degree of weed infestation in the fields in the protective zone of RPN depended on environment conditions. Both winter and spring cereals in majority of soils were most infested by: Cenaturea cyanus, Apera spica-venti and Vicia hirsta. In the lightest podsolic soils, made of loose sand and slightly loamy sand. winter and spring cereals were additionally infested by Equisetum arvense and two acidophylic species: Seleranthus annuus and Spergula arvensis. The crops in brown loess soil were infested by Matricaria maritima subsp. inodora. The most difficult weed species in brown soil formed from gaizes and limestone soil were: Convolvulus arvensis, Papaver rhoeas and Galium aparine. Moreover winter cercals in limestone soil showed high or medium infestation with Consolida regalis, Aethusa cynapium, Lathyrus tuberosus and low infestation with Apera spica-venti and Centaurea cyanus. Spring cereals were less infested than winter cereals. Apera spica-venti and Centaurea cyanus were less common with spring cereals than with winter cereals. Also, spring cereals showed high or medium infestation with Convolvulus arvensis. Spring cereals in some soil units were infested by Chenopodium album and Stellaria media. There was also higher infestation of spring cereals in limestone soils with Avena fatua, Veronica persica, Sinapis arvensis and Sonchus arvensis, compared to winter cereals in limestone soils.

Severe water intoxication and secondary depressive syndrome in relation to delusional infestation

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Lai J

2016-02-01

Full Text Available Jianbo Lai,1 Qiaoqiao Lu,1 Yi Xu,1,2 Shaohua Hu1,2 1Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China; 2The Key Laboratory of Mental Disorder’s Management in Zhejiang Province, Hangzhou, People’s Republic of China Abstract: This study presents a case of severe water intoxication in a female patient with delusional infestation. Self-induced excessive water ingestion is a rare medical condition, which has not been reported in patients with delusional infestation yet. The patient in this case study was a 60-year-old Chinese woman, who was admitted to our hospital because of a feeling of skin infestation. She suffered from loss of consciousness and generalized tonic–clonic seizure after drinking 12 L of water during bowel cleansing before colonoscopy. Sufficient laboratory and imaging examinations were performed to exclude other possible causes of severe hyponatremia, such as hypothyroidism, diabetes insipidus, and syndrome of inappropriate antidiuretic hormone. Besides, the cystic lesion in the posterior pituitary revealed by cranial magnetic resonance imaging was not accountable for her delusional symptoms as well as excessive drinking behavior. Her delusional symptoms were in complete remission with a combination of risperidone and aripiprazole. However, nearly 3 months after discharge, this patient suffered from depressed mood and was diagnosed with depressive syndrome, and even attempted suicide. This case highlights the possibility of self-induced water intoxication in patients with delusional infestation, inevitably adding to the complexity of the disease, and indicates the necessity of precautions for secondary psychotic or mood problems after symptomatological remission. Keywords: delusional infestation, depressive syndrome, suicide, water intoxication

Towards Sustainable Growth Business Models

Energy Technology Data Exchange (ETDEWEB)

Kamp-Roelands, N.; Balkenende, J.P.; Van Ommen, P.

2012-03-15

The Dutch Sustainable Growth Coalition (DSGC) has the following objectives: The DSGC aims to pro-actively drive sustainable growth business models along three lines: (1) Shape. DSGC member companies aim to connect economic profitability with environmental and social progress on the basis of integrated sustainable growth business models; (2) Share. DSGC member companies aim for joint advocacy of sustainable growth business models both internationally and nationally; and (3) Stimulate. DSGC member companies aim to stimulate and influence the policy debate on enabling sustainable growth - with a view to finding solutions to the environmental and social challenges we are facing. This is their first report. The vision, actions and mission of DSGC are documented in the Manifesto in Chapter 2 of this publication. Chapter 3 contains an overview of key features of an integrated sustainable growth business model and the roadmap towards such a model. In Chapter 4, project examples of DSGC members are presented, providing insight into the hands-on reality of implementing the good practices. Chapter 5 offers an overview of how the Netherlands provides an enabling environment for sustainable growth business models. Chapter 6 offers the key conclusions.

Evaluation on the effectiveness of actions for controlling infestation by rodents in Campo Limpo region, Sao Paulo Municipality, Brazil.

Science.gov (United States)

de Masi, Eduardo; Vilaça, Pedro José; Razzolini, Maria Tereza Pepe

2009-08-01

Rodents are responsible for the transmission of more than 60 diseases both to human beings and to domestic animals. The increase in rodent infestation in a given area brings several health problems to the nearby population. Thus, when infestation increases, it is time to take intervention measures. Although many countries have implemented programs aimed at controlling rodent infestation, literature on studies evaluating the effectiveness of intervention measures in urban areas is scarce. Aimed at contributing to the understanding of rodents' population dynamics in urban areas, the objective of this study was to evaluate the effectiveness of the control methods proposed by "Programa de Vigilancia e Controle de Roedores do Municipio de Sao Paulo" (Program for Rodents Surveillance and Control in Sao Paulo Municipality), conducted on Jardim Comercial District. As a first step, a survey to assess infestation rates was conducted in 1529 dwellings located in the area studied. After that, a chemical control upon rodents was accomplished in every dwelling infested. One week and six months after completion of control measures, a new evaluation on infestation rates was carried out, in order to verify the effectiveness of the procedures taken and to estimate the re-infestation capacity. Initial infestation rate was 40.0%, and the final infestation rate, 14.4%. Therefore, the effectiveness of the control methods utilized was 63.8%. It can thus be concluded that the control methods applied were quite effective.

One-Humped Camels (Camelus dromedaries Hard Ticks Infestation in Qeshm Island, Iran

Directory of Open Access Journals (Sweden)

Saeed Nazifi

2011-06-01

Full Text Available The economic importance of tick infestation on camels are important as they are important meat and milk producer animals in the less vegetation area of Iran and their health and production are greatly affected by the high tick infestation. In this investigation, tick infestations on camels (Camelus dromedarius were determined in Qeshm Island, Iran. A total number of 912 adult ticks (472 males and 440 females were collected and identified. Hyalomma dromedarii was the predominant tick specie and accounted for 61.9% of the adult ticks. Other hard ticks were H. anatolicum excavatum (22 %, H. asiaticum asiaticum (14.2 %, H. marginatum (1.9 %, H. impeltatum (0.4 % and Ripicephalus bursa (0.4 %. In conclusion, The provision of tick control programs in the Qeshm Island would seem a prerequisite for improving camel meat and milk production.

Recognition of mite-infested brood by honeybee (Apis mellifera) workers may involve thermal sensing.

Science.gov (United States)

Bauer, Daniel; Wegener, Jakob; Bienefeld, Kaspar

2018-05-01

Hygienic behavior, i.e. the removal of diseased or damaged brood by worker honey bees (Apis mellifera), is seen as one of the principal behavioral elements of this species' social immunity. Identification of the stimuli that trigger it would be helpful in searching for biochemical and molecular markers of this important breeding trait. While many studies at the genomic, transcriptomic, and behavioral level have pointed to the implication of chemical cues, we here hypothesized that thermal cues are alternatively/additionally involved. To test this hypothesis, we first measured whether infestation by the mite Varroa destructor (a condition known to induce hygienic behavior) leads to a thermal gradient between affected and unaffected brood. We found that infested brood cells were between 0.03 and 0.19 °C warmer than uninfested controls. Next, we tested whether artificially heating an area of a brood comb would increase the removal of infested or uninfested brood as compared to an unheated control area, and found that this was not the case. Finally, we investigated whether the heating of individual brood cells, as opposed to comb areas, would influence brood removal from cells adjacent to the heated one. This was the case for uninfested, though not for infested cells. We conclude that infestation by V. destructor leads to a heating of brood cells that should be perceivable by bees, and that small-scale temperature gradients can influence brood removal. This makes it appear possible that thermal cues play a role in triggering hygienic behavior of honey bees directed at varroa-infested larvae/pupae, although our results are insufficient to prove such an involvement. Copyright © 2018. Published by Elsevier Ltd.

of different weed control methods on Weed infestation, growth

African Journals Online (AJOL)

thinkexploitsint'l

This weed control method also resulted in significantly better growth and ... proper management, it is possible to obtain 2,500 kg ha-1 (Onwueme and Sinha, 1991). ... however, time consuming, labour – intensive, strenuous and generally ...

There are more asthmatics in homes with high cockroach infestation

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Sarinho E.

2004-01-01

Full Text Available Although asthma has been commonly associated with sensitivity to cockroaches, a clear causal relationship between asthma, allergy to cockroaches and exposure levels has not been extensively investigated. The objective of the present study was to determine whether asthma occurs more frequently in children living in homes with high cockroach infestation. The intensity of household infestation was assessed by the number of dead insects after professional pesticide application. Children living in these houses in the metropolitan area of Recife, PE, were diagnosed as having asthma by means of a questionnaire based on the ISAAC study. All children had physician-diagnosed asthma and at least one acute exacerbation in the past year. Children of both sexes aged 4 to 12 years who had been living in the households for more than 2 years participated in this transverse study and had a good socioeconomic status. In the 172 houses studied, 79 children were considered to have been exposed to cockroaches and 93 not to have been exposed. Children living in residences with more than 5 dead cockroaches after pesticide application were considered to be at high infestation exposure. Asthma was diagnosed by the questionnaire in 31.6% (25/79 of the exposed group and in 11.8% (11/93 of the non-exposed group (P = 0.001, with a prevalence ratio of 3.45 (95%CI, 1.48-8.20. The present results indicate that exposure to cockroaches was significantly associated with asthma among the children studied and can be considered a risk factor for the disease. Blattella germanica and Periplaneta americana were the species found in 96% of the infested houses.

Lice infesting horses in three agroecological zones in central Oromia.

Science.gov (United States)

Tafese, Adane; Jibat, Tariku; Aklilu, Nigatu; Zewdu, Hanna; Kumsa, Bersissa

2014-12-01

A cross-sectional study was conducted to determine the prevalence and species composition of lice infesting horses in three agroecological zones in seven different districts in central Oromia from November 2011 to April 2012. For this purpose, a total of 420 horses were thoroughly examined for presence of lice. Collected lice were identified to species level under a microscope. The study showed an overall prevalence of 28.8 % (121/420) lice infestation on horses. We identified two spp. of lice on horses namely, Bovicola (Werneckiella) equi and Haematopinus asini with an overall prevalence of 22.9 % (96/420) and 5.9 % (25/420), respectively. The overall prevalence of lice infestation on horses in districts was 48.3, 43.3, 33.3, 23.3, 21.7, 18.3 and 13.3 %, in Debre Brehan, Shashemene, Hawassa, Akaki, Adama, Modjo and Bishoftu, respectively. B. equi was encountered as the predominant species on horses in all districts. Higher overall prevalence of lice infestation was recorded in highland agroecology than mid and lowland agroecological zones. Similarly, our study revealed significantly higher overall prevalence of lice on saddle horses than on cart horses. In view of the findings of the present study two species of lice are responsible for health and welfare problems of horses in all the districts. Detailed epidemiological studies on the significance, prevalence and role of lice as vectors of zoonotic pathogens in different agroecological zones, breeds and management systems warrant urgent attention. Animal owners and veterinarians should consider lice control in horses as part of the ectoparasite control in other species of animals.

Ectoparasites in urban stray cats in Jerusalem, Israel: differences in infestation patterns of fleas, ticks and permanent ectoparasites.

Science.gov (United States)

Salant, H; Mumcuoglu, K Y; Baneth, G

2014-09-01

In a period cross-sectional study performed to examine ectoparasites on 340 stray cats in Jerusalem, Israel, 186 (54.7%) were infested with the cat flea, Ctenocephalides felis (Siphonaptera: Pulicidae), 49 (14.4%) with the cat louse, Felicola subrostratus (Phthiraptera: Trichodectidae), 41 (12.0%) with the ear mite, Otodectes cynotis (Astigmata: Psoroptidae), three (0.9%) with the fur mite, Cheyletiella blakei (Trobidiformes: Cheyletidae), two (0.6%) with the itch mite Notoedres cati (Astigmata: Sarcoptidae), and 25 (7.3%) with ticks of the species Rhipicephalus sanguineus sensu lato (Ixodida: Ixodidae), Rhipicephalus turanicus or Haemaphysalis adleri (Ixodida: Ixodidae). A higher number of flea infestations was observed in apparently sick cats (P < 0.05) and in cats aged < 6 months (P < 0.05). The proportion of flea-infested cats (P < 0.01), as well as the number of fleas per infested cat (P < 0.01), was higher in autumn than in other seasons. By contrast with findings in cats with flea infestations, rates of infestation with ticks were higher amongst cats with clinical signs (P < 0.01) and cats aged ≥ 6 months (P < 0.05). The high rates of ectoparasite infestation in the cats studied constitute a risk for the spread of vector-borne infections of zoonotic and veterinary importance. © 2013 The Royal Entomological Society.

CONCOMITANT HELMINTHIC AND ENTERO-PROTOZOAL INFESTATION IN INDIAN PEAFOWL

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B. Dutta

2013-06-01

Full Text Available Concomitant infestation of Ascaridia spp. along with Raillietina spp. and Emeria spp. has been identified in Indian Peafowl (Pavo cristatus of Ramnabagan Mini Zoo, Burdwan, West Bengal, India.

Infestation of zooplankton with Triaenophorus and Proteocephalus procercoids (Cestoda in a deep oligotrophic lake

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Peter Anegg

2014-07-01

Full Text Available In spring 2004, a massive infestation of the whitefish population in the Austrian Lake Achensee with Triaenophorus crassus was observed. Procercoids, the larval stage of parasitic cestodes, infest copepods as their first intermediate host. Therefore, in spring 2011, zooplankton samples were taken weekly at two sampling sites and depth ranges to determine the abundances of crustaceans as well as percentages of infected copepods and temporal occurrence of parasites. In addition, whitefish (Coregonus lavaretus stomach contents were analysed for food spectrum and parasite infestation. From the end of June to mid-August, procercoids of Triaenophorus spp. were detected in Cyclops abyssorum, the only first intermediate host for this parasite in Lake Achensee. Highest percentages of infected copepods were reached in mid-July (prevalence: 0.38%. Furthermore, an infestation of Proteocephalus sp. was observed in this copepod species, which occurred earlier until the end of the sampling period (prevalence: 1.34%. Besides C. abyssorum, also Eudiaptomus gracilis was occasionally infected with Proteocephalus (prevalence: 0.05%. The procercoids were found in both depth ranges, with no clear vertical infestation preference. More female C. abyssorum were Triaenophorus-infected than males, while the opposite was observed for Proteocephalus infection. The whitefish stomachs contained large numbers of Proteocephalus and Triaenophorus procercoids, coinciding with the occurrence of these parasites in the copepods.

Direct and indirect impacts of infestation of tomato plant by Myzus persicae (Hemiptera: Aphididae on Bemisia tabaci (Hemiptera: Aleyrodidae.

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Xiao-Ling Tan

Full Text Available The impacts of infestation by the green peach aphid (Myzus persicae on sweetpotato whitefly (Bemisia tabaci settling on tomato were determined in seven separate experiments with whole plants and with detached leaves through manipulation of four factors: durations of aphid infestation, density of aphids, intervals between aphid removal after different durations of infestation and the time of whitefly release, and leaf positions on the plants. The results demonstrated that B. tabaci preferred to settle on the plant leaves that had not been infested by aphids when they had a choice. The plant leaves on which aphids were still present (direct effect had fewer whiteflies than those previously infested by aphids (indirect effect. The whiteflies were able to settle on the plant which aphids had previously infested, and also could settle on leaves with aphids if no uninfested plants were available. Tests of direct factors revealed that duration of aphid infestation had a stronger effect on whitefly landing preference than aphid density; whitefly preference was the least when 20 aphids fed on the leaves for 72 h. Tests of indirect effects revealed that the major factor that affected whitefly preference for a host plant was the interval between the time of aphid removal after infestation and the time of whitefly release. The importance of the four factors that affected the induced plant defense against whiteflies can be arranged in the following order: time intervals between aphid removal and whitefly release > durations of aphid infestation > density of aphids > leaf positions on the plants. In conclusion, the density of aphid infestation and time for which they were feeding influenced the production of induced compounds by tomatoes, the whitefly responses to the plants, and reduced interspecific competition.

Effects of Ginkgo biloba constituents on fruit-infesting behavior of codling moth (Cydia pomonella) in apples.

Science.gov (United States)

Pszczolkowski, Maciej A; Durden, Kevin; Sellars, Samantha; Cowell, Brian; Brown, John J

2011-10-26

Codling moth, Cydia pomonella (L.), is a cosmopolitan pest of apple, potentially causing severe damage to the fruit. Currently used methods of combating this insect do not warrant full success or are harmful to the environment. The use of plant-derived semiochemicals for manipulation with fruit-infesting behavior is one of the new avenues for controlling this pest. Here, we explore the potential of Ginkgo biloba and its synthetic metabolites for preventing apple feeding and infestation by neonate larvae of C. pomonella. Experiments with crude extracts indicated that deterrent constituents of ginkgo are present among alkylphenols, terpene trilactones, and flavonol glycosides. Further experiments with ginkgo synthetic metabolites of medical importance, ginkgolic acids, kaempferol, quercetin, isorhamnetin, ginkgolides, and bilobalide, indicated that three out of these chemicals have feeding deterrent properties. Ginkgolic acid 15:0 prevented fruit infestation at concentrations as low as 1 mg/mL, bilobalide had deterrent effects at 0.1 mg/mL and higher concentrations, and ginkgolide B at 10 mg/mL. On the other hand, kaempferol and quercetin promoted fruit infestation by codling moth neonates. Ginkgolic acids 13:0, 15:1, and 17:1, isorhamnetin, and ginkgolides A and C had no effects on fruit infestation-related behavior. Our research is the first report showing that ginkgo constituents influence fruit infestation behavior and have potential applications in fruit protection.

Settling and growth of D. polymorpha in the raw water circuits of the Cattenom nuclear power plant (Moselle, France)

International Nuclear Information System (INIS)

Moreteau, J.C.; Khalanski, M.

1994-05-01

A''biological profile'' of the zebra mussels which are infesting certain circuits of the Cattenom nuclear power plant has been provided by data collected during a three-year measurement programme (1991-1993). The larval settlement periods and the growth of settled mussels were monitored. A simple mathematical model, which calculates the shell growth on the long term, was calibrated with the field data. It is based on three functions representing the effect of the initial size, water temperature and fool availability (plankton chlorophyll a). (authors). 13 refs., 7 figs., 4 tabs

Nonlinear Growth Models as Measurement Models: A Second-Order Growth Curve Model for Measuring Potential.

Science.gov (United States)

McNeish, Daniel; Dumas, Denis

2017-01-01

Recent methodological work has highlighted the promise of nonlinear growth models for addressing substantive questions in the behavioral sciences. In this article, we outline a second-order nonlinear growth model in order to measure a critical notion in development and education: potential. Here, potential is conceptualized as having three components-ability, capacity, and availability-where ability is the amount of skill a student is estimated to have at a given timepoint, capacity is the maximum amount of ability a student is predicted to be able to develop asymptotically, and availability is the difference between capacity and ability at any particular timepoint. We argue that single timepoint measures are typically insufficient for discerning information about potential, and we therefore describe a general framework that incorporates a growth model into the measurement model to capture these three components. Then, we provide an illustrative example using the public-use Early Childhood Longitudinal Study-Kindergarten data set using a Michaelis-Menten growth function (reparameterized from its common application in biochemistry) to demonstrate our proposed model as applied to measuring potential within an educational context. The advantage of this approach compared to currently utilized methods is discussed as are future directions and limitations.

Identification of brome grass infestations in southwest Oklahoma using multi-temporal Landsat imagery

Science.gov (United States)

Yan, D.; de Beurs, K.

2013-12-01

The extensive infestation of brome grasses (Cheatgrass, Rye brome and Japanese brome) in southwest Oklahoma imposes negative impacts on local economy and ecosystem in terms of decreasing crop and forage production and increasing fire risk. Previously proposed methodologies on brome grass detection are found ill-suitable for southwest Oklahoma as a result of similar responses of background vegetation to inter-annual variability of rainfall. In this study, we aim to identify brome grass infestations by detecting senescent brome grasses using the 2011 Cultivated Land Cover Data Sets and the difference Normalized Difference Infrared Index (NDII) derived from multi-temporal Landsat imagery. Landsat imageries acquired on May 18th and June 10th 2013 by Operational Land Imager and Enhanced Thematic Mapper plus were used. The imagery acquisition dates correspond to the peak growth and senescent time of brome grasses, respectively. The difference NDII was calculated by subtracting the NDII image acquired in May from the June NDII image. Our hypotheses is that senescent brome grasses and crop/pasture fields harvested between the two image acquisition dates can be distinguished from background land cover classes because of their increases in NDII due to decreased water absorption by senescent vegetation in the shortwave infrared region. The Cultivated Land Cover Data Sets were used to further separate senescent brome grass patches from newly harvested crop/pasture fields. Ground truth data collected during field trips in June, July and August of 2013 were used to validate the detection results.

Infestation of natural populations of earthworm cocoons by rhabditid and cephalobid nematodes

DEFF Research Database (Denmark)

Kraglund, HO; Ekelund, Flemming

2002-01-01

Nematodes infested 13 of 100 earthworm cocoons from a compost pile and 17 of 197 cocoons from a permanent pasture soil. Between one and 2000 nematodes were found within the infested cocoons. All nematodes found in cocoons from the compost pile belonged to the genus Rhabditis, while Rhabditis spp....... as well as members of Cephalobidae infested earthworm cocoons in the pasture soil. In cultures established from cocoons found in the pasture soil, at least five different types of nematodes belonging to the family Cephalobidae were found. Acrobeloides nanus was found in six cocoons, Cephalobus persegnis...... was found in four and Chiloplacus minimus was found in one cocoon. We suggest that earthworm - nematode interactions may be an important pathway for the transfer of carbon in terrestrial ecosystems, and that the inclusion of these pathways may lead to a better understanding of soil food web functioning....

Modelos analíticos do crescimento populacional de Sitophilus zeamais em trigo armazenado Analytical models for population growth of Sitophilus zeamais in stored wheat

Directory of Open Access Journals (Sweden)

Arienilmar A. L. da Silva

2006-03-01

Full Text Available Para se atingir os objetivos propostos neste trabalho, desenvolveram-se modelos analíticos do crescimento populacional de S. zeamais em grãos de trigo armazenados com teor de umidade de 11,1%. O crescimento populacional foi avaliado durante 90 dias de armazenagem, nas temperaturas de 16, 20, 24, 28, 32 e 36 ºC, partindo-se de infestações iniciais que variaram de 1,3 a 9,3 insetos por kg de trigo. Os modelos explicaram de 93,9 a 98,9% da variação na densidade populacional. O crescimento populacional foi afetado pelo tamanho da população que iniciou a infestação, ou seja, quanto maior foi a infestação inicial maior também foi o crescimento populacional ao longo do tempo de armazenagem, que ocorreu na temperatura de 28 ºC e diminuiu drasticamente abaixo e acima desta. Na temperatura de 36 ºC, todas as populações foram extintas entre 15 e 45 dias de armazenagem, mas nenhuma população se extinguiu a 16 ºC. Os modelos apresentaram excelentes ajustes, estando em conformidade com os princípios gerais da dinâmica de populações de insetos em um sistema de grãos armazenados e descrevem muito bem o crescimento populacional de S. zeamais em relação ao efeito da temperatura e da densidade populacional inicial.Analytical models of population growth were developed for Sitophilus zeamais, in grain wheat stored at 11.1% of moisture content. Population growth was monitored for 90 days at the temperatures of 16, 20, 24, 28, 32 and 36 ºC and initial adult population densities varying between 1.3 and 9.3 insects per kg. The models obtained explained between 93.9 and 98.99% of the variation in density of adult insects. The population growth was affected by initial population density of infestation and increased proportionately with degree of infestation. The highest population growth occurred at 28 ºC and drastically decreased for lower and higher temperatures. Population extinction took place between 15 and 45 days of storage for all

Residual Infestation and Recolonization during Urban Triatoma infestans Bug Control Campaign, Peru1

Science.gov (United States)

Buttenheim, Alison M.; Pumahuanca, Maria-Luz Hancco; Calderón, Javier E. Quintanilla; Salazar, Renzo; Carrión, Malwina; Rospigliossi, Andy Catacora; Chavez, Fernando S. Malaga; Alvarez, Karina Oppe; Cornejo del Carpio, Juan; Náquira, César; Levy, Michael Z.

2014-01-01

Chagas disease vector control campaigns are being conducted in Latin America, but little is known about medium-term or long-term effectiveness of these efforts, especially in urban areas. After analyzing entomologic data for 56,491 households during the treatment phase of a Triatoma infestans bug control campaign in Arequipa, Peru, during 2003–2011, we estimated that 97.1% of residual infestations are attributable to untreated households. Multivariate models for the surveillance phase of the campaign obtained during 2009–2012 confirm that nonparticipation in the initial treatment phase is a major risk factor (odds ratio [OR] 21.5, 95% CI 3.35–138). Infestation during surveillance also increased over time (OR 1.55, 95% CI 1.15–2.09 per year). In addition, we observed a negative interaction between nonparticipation and time (OR 0.73, 95% CI 0.53–0.99), suggesting that recolonization by vectors progressively dilutes risk associated with nonparticipation. Although the treatment phase was effective, recolonization in untreated households threatens the long-term success of vector control. PMID:25423045

Volatiles from Psylla-infested pear trees and their possible involvement in attraction of anthocorid predators

NARCIS (Netherlands)

Scutareanu, P.; Drukker, B.; Bruin, J.; Posthumus, M.A.; Sabelis, M.W.

1997-01-01

Previous work showed that anthocorid predators aggregate around gauze cages containing Psylla-infested trees in a pear orchard. Because anthocorids responded to odor from Psylla-infested leaves in a laboratory test, it was hypothesized that these aggregative responses in the field were triggered by

Survey of Hard Ticks (Ixodidae) Infesting Camels ( Camelus ...

African Journals Online (AJOL)

To determine the prevalence and abundance of hard ticks infesting camels, 414 nomadic one - humped camels in Kano State, northwestern Nigeria were selected by random sampling and examined for the presence of ticks on their bodies between January and December 2007. Three species of ticks, Amblyomma ...

Thelazia callipaeda infestation in Bangladesh: a case report.

Science.gov (United States)

Akhanda, A H; Akonjee, A R; Hossain, M M; Rahman, M A; Mishu, F A; Hasan, M F; Akhanda, T H

2013-07-01

A 5 years old girl was admitted to Ophthalmology department of Mymensingh Medical College Hospital, Mymensingh with excessive watering, redness and movement of something in her right eye for last 2 months. She had unaided visual acuity- 6/6, matted eye lashes and mucoid discharge in right eye. Follicles were present on the fornices and lower palpebral conjunctiva of the same eye. On eversion of the right upper lid there were silicon tube like coiled moving structures seen at the lateral part of the upper fornics. Six nematodes were seen in the upper fornics around the duct of lacrimal glands. After removing the nematodes, one specimen was sent to parasitology department of Bangladesh Agriculture University for species identification. They reported that sending specimen is an adult "Thelazia Callipaeda". By the present study, the presence of human ocular T. callipaeda infestation is second reported case in Bangladesh. Ophthalmologists should be aware about parasitic infestation of conjunctiva.

Infestation of fruit fly, Bactrocera (Diptera: Tephritidae) on mango ...

African Journals Online (AJOL)

Infestation of fruit fly, Bactrocera (Diptera: Tephritidae) on mango ( Mangifera indica L.) in peninsular Malaysia. ... Abstract. A survey was carried out in mango orchards in Peninsular Malaysia with aimed to determine the ... HOW TO USE AJOL.

Efficacy of imidacloprid + moxidectin and selamectin topical solutions against the KS1 Ctenocephalides felis flea strain infesting cats

Directory of Open Access Journals (Sweden)

Dryden Michael W

2011-09-01

Full Text Available Abstract Background Two studies were conducted to evaluate and compare the efficacy of imidacloprid + moxidectin and selamectin topical solutions against the KS1 flea strain infesting cats. In both studies the treatment groups were comprised of non-treated controls, 6% w/v selamectin (Revolution®; Pfizer Animal Health topical solution and 10% w/v imidacloprid + 1% w/v moxidectin (Advantage Multi® for Cats, Bayer Animal Health topical solution. All cats were infested with 100 fleas on Days -2, 7, 14, 21, and 28. The difference in the studies was that in study #1 efficacy evaluations were conducted at 24 and 48 hours post-treatment or post-infestation, and in study #2 evaluations were conducted at 12 and 24 hours. Results In study #1 imidacloprid + moxidectin and the selamectin formulation provided 99.8% and 99.0% efficacy at 24 hours post-treatment. On day 28, the 24 hour efficacy of the selamectin formulation dropped to 87.1%, whereas the imidacloprid + moxidectin formulation provided 98.9% efficacy. At the 48 hour assessments following the 28 day infestations, efficacy of the imidacloprid + moxidectin and selamectin formulations was 96.8% and 98.3% respectively. In study # 2 the efficacy of the imidacloprid + moxidectin and selamectin formulations 12 hours after treatment was 100% and 69.4%, respectively. On day 28, efficacy of the imidacloprid + moxidectin and selamectin formulations 12 hours after infestation was 90.2% and 57.3%, respectively. In study #2 both formulations provided high levels of efficacy at the 24 hour post-infestation assessments, with selamectin and imidacloprid + moxidectin providing 95.3% and 97.5% efficacy, following infestations on day 28. Conclusions At the 24 and 48 hour residual efficacy assessments, the imidacloprid + moxidectin and selamectin formulations were similarly highly efficacious. However, the imidacloprid + moxidectin formulation provided a significantly higher rate of flea kill against the KS1 flea

An experiment to detect apples infested by the peach fruit moth, Carposina sasakii matsumura (Lepidoptera: Carposinidae), using near-infrared spectroscopy

International Nuclear Information System (INIS)

Toyoshima, S.; Nakamoto, Y.; Takanashi, M.; Masuda, T.

2006-01-01

The potential of near-infrared spectroscopy to detect apples ('Fuji' cultivar) infested by the peach fruit moth, Carposina sasakii, was evaluated using a prevalent NIR device. A calibration equation was developed using both the NIR spectra and injury levels of the infested fruits. The equation predicted the injury levels of fruits using a simple correlation coefficient of 0.8868 and a standard error of prediction of 0.3688. At the level of estimates to discard ca 90% of infested fruits, 90.15% of the infested fruits and 39.24% of the uninfested fruits were excluded from the samples. Although its accuracy was not sufficient, the present NIR device has the potential to identify internally infested fruits

Parasites and vector-borne diseases in client-owned dogs in Albania: infestation with arthropod ectoparasites.

Science.gov (United States)

Shukullari, Enstela; Rapti, Dhimitër; Visser, Martin; Pfister, Kurt; Rehbein, Steffen

2017-01-01

To establish the diversity and seasonality of ectoparasite infestation in client-owned dogs in Albania, 602 dogs visiting four small animal clinics in Tirana from March 2010 to April 2011 inclusive were examined for ectoparasites by full body search and total body comb. In addition, ear swab specimens collected from all dogs and scrapings taken from skin lesions suspicious of mite infestation were examined for parasitic mites. Overall, 93 dogs (15.4 %, 95%CI 12.6-18.6) were demonstrated to be infested, and nine species of ectoparasites were identified: Ixodes ricinus, 0.8 %; Rhipicephalus sanguineus s. l., 8.1 %; Demodex canis, 0.2 %; Sarcoptes scabiei, 0.7 %; Otodectes cynotis, 2.8 %; Ctenocephalides canis, 4.8 %; Ctenocephalides felis, 3.0 %; Pulex irritans, 0.2 %; and Trichodectes canis, 0.2 %. Single and multiple infestations with up to four species of ectoparasites concurrently were recorded in 67 (11.1 %, 95%CI 8.7-13.9) and 26 dogs (4.3 %, 95%CI 2.8-6.3), respectively. On univariate analysis, the category of breed (pure breed dogs vs. mixed-breed dogs), the dog's purpose (pet, hunting dog, working dog), the housing environment (mainly indoors/indoors with regular outside walking vs. yard plus kennel/run), the history of ectoparasiticide treatment and the season of examination were identified as significant (p < 0.05) factors predisposing dogs to various ectoparasites, while the variables dog's age, gender, the dog's habitat (city, suburban, rural) and the presence/absence of other pets were not significant predictors. Multivariate logistic regression analysis for factors associated with overall ectoparasitism revealed that dogs treated with ectoparasiticides at least once per year (odds ratio [OR] = 0.24; p < 0.001) had a significantly lower risk of infestation compared with dogs not treated against ectoparasite infestation. Dogs examined during spring, summer and autumn (OR = 7.08, 7.43 and 2.48, respectively; all p < 0

Identification and Characterization of Trichoderma Species Damaging Shiitake Mushroom Bed-Logs Infested by Camptomyia Pest.

Science.gov (United States)

Kim, Jun Young; Kwon, Hyuk Woo; Yun, Yeo Hong; Kim, Seong Hwan

2016-05-28

The shiitake mushroom industry has suffered from Camptomyia (gall midges) pest, which feeds on the mycelium of shiitake mushroom during its cultivation. It has been postulated that fungal damage of shiitake bed-logs is associated with infestation by the insect pest, but this is not well understood. To understand the fungal damage associated with Camptomyia pest, various Trichoderma species were isolated, identified, and characterized. In addition to two previously known Trichoderma species, T. citrinoviride and T. deliquescens, two other Trichoderma species, T. harzianum and T. atroviride, were newly identified from the pestinfested bed-log samples obtained at three mushroom farms in Cheonan, Korea. Among these four species, T. harzianum was the most evident. The results of a chromogenic media-based assay for extracellular enzymes showed that these four species have the ability to produce amylase, carboxyl-methyl cellulase, avicelase, pectinase, and β-glucosidase, thus indicating that they can degrade wood components. A dual culture assay on PDA indicated that T. harzianum, T. atroviride, and T. citrinoviride were antagonistic against the mycelial growth of a shiitake strain (Lentinula edodes). Inoculation tests on shiitake bed-logs revealed that all four species were able to damage the wood of bed-logs. Our results provide evidence that the four green mold species are the causal agents involved in fungal damage of shiitake bed-logs infested by Camptomyia pest.

Considérations nosographiques sur le délire d'infestation parasitaire à travers trois observations cliniques

Science.gov (United States)

Berhili, Nabil; Bout, Amine; Hlal, Hayat; Aarab, Chadya; Aalouane, Rachid; Rammouz, Ismail

2016-01-01

Le syndrome d'Ekbom, ou délire d'infestation parasitaire, est une pathologie rare, caractérisée par la conviction inébranlable d'avoir une peau infestée d'insectes ou de parasites. Il s'agit d'un délire monothématique à mécanisme hallucinatoire qui touche typiquement les femmes d’âge avancé. Nous rapportons les cas de trois patients qui présentent un délire d'infestation parasitaire dans des contextes cliniques différents. Le premier patient souffre d'un délire d'infestation isolé correspondant à la forme décrite par Karl Ekbom. Le deuxième cas présente un délire d'infestation secondaire, s'inscrivant dans le cadre d'une leuco-encéphalopathie de type CADASIL. Enfin, le troisième patient se présente dans un tableau évocateur d'un épisode dépressif avec une caractéristique psychotique qui intègre le délire d'infestation. Ces trois vignettes cliniques illustrent parfaitement le caractère trans-nosographique de ce syndrome ainsi que les difficultés de prise en charge de ces patients, tant au niveau de l'alliance thérapeutique que sur le plan des choix en matière de traitement pharmacologiques. PMID:27642468

Gene expression and plant hormone levels in two contrasting rice genotypes responding to brown planthopper infestation.

Science.gov (United States)

Li, Changyan; Luo, Chao; Zhou, Zaihui; Wang, Rui; Ling, Fei; Xiao, Langtao; Lin, Yongjun; Chen, Hao

2017-02-28

The brown planthopper (BPH; Nilaparvata lugens Stål) is a destructive piercing-sucking insect pest of rice. The plant hormones salicylic acid (SA) and jasmonic acid (JA) play important roles in plant-pest interactions. Many isolated rice genes that modulate BPH resistance are involved in the metabolism or signaling pathways of SA, JA and ethylene. 'Rathu Heenati' (RH) is a rice cultivar with a high-level, broad-spectrum resistance to all BPH biotypes. Here, RH was used as the research material, while a BPH-susceptible rice cultivar 'Taichung Native 1' (TN1) was the control. A cDNA microarray analysis illuminated the resistance response at the genome level of RH under BPH infestation. The levels of SA and JA in RH and TN1 seedlings after BPH infestation were also determined. The expression pattern clustering indicated that 1467 differential probe sets may be associated with constitutive resistance and 67 with the BPH infestation-responsive resistance of RH. A Venn diagram analysis revealed 192 RH-specific and BPH-inducible probe sets. Finally, 23 BPH resistance-related gene candidates were selected based on the expression pattern clustering and Venn diagram analysis. In RH, the SA content significantly increased and the JA content significantly decreased after BPH infestation, with the former occurring prior to the latter. In RH, the differential genes in the SA pathway were synthesis-related and were up-regulated after BPH infestation. The differential genes in the JA pathway were also up-regulated. They were jasmonate ZIM-domain transcription factors, which are important negative regulators of the JA pathway. Comparatively, genes involved in the ET pathway were less affected by a BPH infestation in RH. DNA sequence analysis revealed that most BPH infestation-inducible genes may be regulated by the genetic background in a trans-acting manner, instead of by their promoters. We profiled the analysis of the global gene expression in RH and TN1 under BPH infestation

Is there an association between bruxism and intestinal parasitic infestation in children?

Science.gov (United States)

Díaz-Serrano, Kranya Victoria; da Silva, Carolina Brunelli Alvares; de Albuquerque, Sérgio; Pereira Saraiva, Maria da Conceição; Nelson-Filho, Paulo

2008-01-01

Multiple factors have been considered in the etiology of bruxism in pediatric patients, among which are infestations by intestinal parasites suggested by some authors. No empirical evidence exists, however, of such association. Therefore, this study's purpose was to investigate the existence of an association between bruxism and intestinal parasitic infestation in children. Fifty-seven 6- to 11-year-olds (30 cases and 27 controls) who had not used anthelminthics 2 months before the baseline examination were enrolled in the study. A diagnosis of bruxism was based on an intraoral clinical examination performed by a single trained examiner and on the parent/guardian's report of any perceived parafunctional habits (questionnaire-based interview). Bruxism cases were defined as those children with a report of currently perceived habits of eccentric or centric bruxism (tooth-grinding and tooth-clenching, respectively) combined with clinical evidence of nonphysiologic wear facets. The volunteers were required to collect 3 fecal samples (1 every 2 to 3 days). Parasitologic analysis was performed using the spontaneous sedimentation method. Data gathered from the intraoral clinical examination, questionnaire, and parasitologic analysis were tabulated and submitted to statistical analysis using the chi-square test and student's t test. Intestinal parasitic infestation was observed in 30% (N=9) of cases and 41% (N=11) of controls, but no statistically significant association was observed (P=.40). This study's findings do not support the existence of an association between intestinal parasitic infestation and bruxism among the evaluated pediatric population.

Modelling the effects of the sterile insect technique applied to Eldana saccharina Walker in sugarcane

Directory of Open Access Journals (Sweden)

L Potgieter

2012-12-01

Full Text Available A mathematical model is formulated for the population dynamics of an Eldana saccharina Walker infestation of sugarcane under the influence of partially sterile released insects. The model describes the population growth of and interaction between normal and sterile E.saccharina moths in a temporally variable, but spatially homogeneous environment. The model consists of a deterministic system of difference equations subject to strictly positive initial data. The primary objective of this model is to determine suitable parameters in terms of which the above population growth and interaction may be quantified and according to which E.saccharina infestation levels and the associated sugarcane damage may be measured. Although many models have been formulated in the past describing the sterile insect technique, few of these models describe the technique for Lepidopteran species with more than one life stage and where F1-sterility is relevant. In addition, none of these models consider the technique when fully sterile females and partially sterile males are being released. The model formulated is also the first to describe the technique applied specifically to E.saccharina, and to consider the economic viability of applying the technique to this species. Pertinent decision support is provided to farm managers in terms of the best timing for releases, release ratios and release frequencies.

Population Growth and Damage Caused by Rhopalosiphum padi (L.) (Hemiptera, Aphididae) on Different Cultivars and Phenological Stages of Wheat.

Science.gov (United States)

Savaris, M; Lampert, S; Salvadori, J R; Lau, D; Pereira, P R V S; Smaniotto, M A

2013-10-01

Among the aphids associated with wheat and other winter cereals, Rhopalosiphum padi (L.) is currently the predominant species in the wheat growing region of southern Brazil. The damage caused by this aphid occurs by direct feeding and/or by the transmission of pathogenic viruses, such as the Barley/Cereal yellow dwarf virus. In order to estimate the direct damage caused by R. padi on wheat, we evaluated the population growth of this aphid during the tillering and elongation stages and its effects on grain yield components. The experiment was conducted in a screenhouse with three wheat cultivars (BRS Guabiju, BRS Timbaúva, and Embrapa 16). The effect of a period of 16 days, starting from an infestation of 40 aviruliferous aphids/plant, was evaluated and compared to non-infested plants. In both stages, the population growth of R. padi was lower on the BRS Timbaúva. Although infestation caused a reduction in the grain yield of the three cultivars, this effect was lower for BRS Timbaúva. The cultivar Embrapa 16 supported higher infestations and was more tolerant to damage than the BRS Guabiju.

Assessment of the cytokine profile in peripheral blood mononuclear cells of naturally Sarcoptes scabiei var. canis infested dogs.

Science.gov (United States)

Singh, Shanker K; Dimri, Umesh; Sharma, Bhaskar; Saxena, Meeta; Kumari, Priyambada

2014-12-15

The mechanism of cytokine secretion from T lymphocytes plays an important role in the immune response of dogs and parasitic skin infestations. Assessment of the cytokine profile of naturally S. scabiei var. canis infested dogs could augment understanding of the pathobiology of canine sarcoptic mange. Therefore, the present study examined the cytokines in peripheral blood mononuclear cells of dogs suffering from sarcoptic mange. Thirteen dogs naturally infected with sarcoptic mange participated in the study. The dogs were found positive for S. scabiei var. canis mites in skin scraping examinations and revealed at least three clinical inclusion criteria. Another five clinically healthy dogs were kept as healthy controls. Peripheral blood mononuclear cells were isolated from heparinized blood samples and used for extraction of mRNA. Further, cDNA was synthesized by using 1 mg of mRNA by reverse transcription using oligonucleotide primers. Relative levels of cytokine expression were compared with normalized glyceraldehyde-3-phosphate dehydrogenase (GAPDH) transcripts. The levels of interleukin-4, interleukin-5 and transforming growth factor beta (TGF-β) mRNA expression in dogs with sarcoptic mange were significantly higher (P ≤ 0.01), whereas the level of tumor necrosis factor alpha (TNF-α) was significantly lower (P ≤ 0.01) in comparison with the healthy dogs. No remarkable difference was seen for interleukin-2 mRNA expression between these animals. An overproduction IL-4 and IL-5 might be involved in immuno-pathogenesis of canine sarcoptic mange. S. scabiei var. canis mites possibly induce an overproduction of TGF-β and reduced expression of TNF-α and thus could be conferring the immune suppression of infested dogs. Copyright © 2014 Elsevier B.V. All rights reserved.

Intraperitoneal ectopic infestation of parasites invading through gastrointestinal tract : CT findings

Energy Technology Data Exchange (ETDEWEB)

Kim, Jeong Kon; Rha, Sung Eun; Ha, Hyun Kwon; Kim, Pyo Nyun; Lee, Moon Gyu; Auh, Yong Ho [Asan Medical Center, Ulsan Univ., Ulsan (Korea, Republic of); Choi, Byung Ihn [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of); Shim, Jae Chul [Inje Univ. College of Medicine, Kimhae (Korea, Republic of); Kim, Hyun [St. Mary' s Hospital, The Catholic Univ. of Korea, Seoul (Korea, Republic of); Lee, Jong Hwa; Ham, Soo Youn [Ulsan Univ. Hospital, Ulsan (Korea, Republic of)

1999-03-01

The purpose of this study was to evaluate the CT findings of parasitic ectopic infestation in the peritoneal cavity, a transitional route for parasites invading the gastrointestinal tract, to migrate to various target organs. CT scans of nine patients with pathologically(n=8) or serologically(n=1) proven intraperitoneal involvement of parasitic infestation were retrospectively reviewed. The primary causes of parasitic infestation in nine patients were Paragonimus westermani(n=5), Sparganosis(n=2), and hepatic fascioliasis(n=2). We analyzed the CT findings with regard to the sites and patterns of lesions in the peritoneal cavity and gastrointestinal track, as well as in other solid organs. The clinical features of these patients were also evaluated. The clinical symptoms and signs were chronic abdominal pain and general weakness in seven patients, while peripheral blood eosinophilia was observed in four. The CT features of these nine patients included multiseptated cystic masses of 2-6cm, diameter (mean 4.1{+-}1.7cm) in the omentum or mesentery in six(67%), omental or mesenteric infiltration in seven(78%), focal peritoneal thickening in seven(78%), 1ymphadenopathy in five(56%), and ascites in four(44%). In six of the nine patients, the gastrointestinal tract(stomach in four, colon in one, both stomach and colon in one) was concomitantly involved with focal wall thickening. Branching patterns of hypoattenuating lesions were noted in the liver of three patients; two of these had hepatic fascioliasis and one had paragonimiasis. Ectopic parasitic infestation in the peritoneal cavity manifests as mass formation, adjacent gastrointestinal wall thickening, and focal peritonitis. An understanding of these image features is important for both early diagnosis and adequate treatment.

Intraperitoneal ectopic infestation of parasites invading through gastrointestinal tract : CT findings

International Nuclear Information System (INIS)

Kim, Jeong Kon; Rha, Sung Eun; Ha, Hyun Kwon; Kim, Pyo Nyun; Lee, Moon Gyu; Auh, Yong Ho; Choi, Byung Ihn; Shim, Jae Chul; Kim, Hyun; Lee, Jong Hwa; Ham, Soo Youn

1999-01-01

The purpose of this study was to evaluate the CT findings of parasitic ectopic infestation in the peritoneal cavity, a transitional route for parasites invading the gastrointestinal tract, to migrate to various target organs. CT scans of nine patients with pathologically(n=8) or serologically(n=1) proven intraperitoneal involvement of parasitic infestation were retrospectively reviewed. The primary causes of parasitic infestation in nine patients were Paragonimus westermani(n=5), Sparganosis(n=2), and hepatic fascioliasis(n=2). We analyzed the CT findings with regard to the sites and patterns of lesions in the peritoneal cavity and gastrointestinal track, as well as in other solid organs. The clinical features of these patients were also evaluated. The clinical symptoms and signs were chronic abdominal pain and general weakness in seven patients, while peripheral blood eosinophilia was observed in four. The CT features of these nine patients included multiseptated cystic masses of 2-6cm, diameter (mean 4.1±1.7cm) in the omentum or mesentery in six(67%), omental or mesenteric infiltration in seven(78%), focal peritoneal thickening in seven(78%), 1ymphadenopathy in five(56%), and ascites in four(44%). In six of the nine patients, the gastrointestinal tract(stomach in four, colon in one, both stomach and colon in one) was concomitantly involved with focal wall thickening. Branching patterns of hypoattenuating lesions were noted in the liver of three patients; two of these had hepatic fascioliasis and one had paragonimiasis. Ectopic parasitic infestation in the peritoneal cavity manifests as mass formation, adjacent gastrointestinal wall thickening, and focal peritonitis. An understanding of these image features is important for both early diagnosis and adequate treatment

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

Science.gov (United States)

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

2018-01-01

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

Variability in snowpack accumulation and ablation associated with mountain pine beetle infestation in western forests

Science.gov (United States)

Biederman, J. A.; Harpold, A. A.; Gochis, D. J.; Reed, D.; Brooks, P. D.

2010-12-01

Seasonal snowcover is a primary source of water to urban and agricultural regions in the western United States, where Mountain Pine Beetle (MPB) has caused rapid and extensive changes to vegetation in montane forests. Levels of MPB infestation in these seasonally snow-covered systems are unprecedented, and it is unknown how this will affect water yield, especially in changing climate conditions. To address this unknown we ask: How does snow accumulation and ablation vary across forest with differing levels of impact? Our study areas in the Rocky Mountains of CO and WY are similar in latitude, elevation and forest structure before infestation, but they vary in the intensity and timing of beetle infestation and tree mortality. We present a record for winter 2010 that includes continuous snow depth as well as stand-scale snow surveys at maximum accumulation. Additional measurements include snowfall, net radiation, temperature and wind speed as well as characterization of forest structure by leaf area index. In a stand uninfested by MPB, maximum snow depth was fairly uniform under canopy (mean = 86 cm, coefficient of variation = 0.021), while canopy gaps showed greater and more variable depth (mean = 117 cm, CV = 0.111). This is consistent with several studies demonstrating that snowfall into canopy gaps depends upon gap size, orientation, wind speed and storm size. In a stand impacted in 2007, snow depth under canopy was less uniform, and there were smaller differences in both mean depth and variability between canopy (mean = 93 cm, CV = 0.072) and gaps (mean = 97 cm, CV = 0.070), consistent with decreased canopy density. In a more recently infested (2009) stand with an intermediate level of MPB impact, mean snow depths were similar between canopy (96 cm, CV = 0.016) and gaps (95 cm, CV = 0.185) but gaps showed much greater variability, suggesting controls similar to those in effect in the uninfested stand. We further use these data to model snow accumulation and

Infestation of Phaseolus Vulgaris (L) by the beanfly Ophiomyia Spp. (Diptera: Agromyzidae) and Its Management by Cultural Practices

International Nuclear Information System (INIS)

Kayitare, Joseph Sibomana

1993-04-01

Cultural practices as management strategy for bean fly control were examined over four cropping seasons in 1991 and 1992 under farmer’s developed field conditions at Oyugis, in Homa Bay District of Western Kenya. In many parts of East and Central Africa, the bean fly is a major constraint to the production of the bean crop (Phaseolus vulgaris), its incidence causes yield losses averaging 47-87%, Control methods used against the pest are mostly insecticides based. Cultural control as a pest management strategy is a less considered area of research which needs to be studied, since it is the first line of defence against pest populations and results in little or no added cost. For this reason studies on five cultural practices (soil fertility, inter cropping, weeding regimes, plant spacing and planting time) on bean fly infestation were undertaken as possible control methods, Increase in nitrogen levels increased bean fly infestation by 12-66%. Phosphorus served as catalyst for nitrogen assimilation. The fertilized plants were more succulent, tender and had more nutrients and therefore offered better conditions for bean fly penetration into bean stems, fecundity and development. However, the infested plants in fertilized soils were able to compensate for the damage caused to them and grew quickly to pass the critical stages. Thus the bean fly infestation had little effect on grain yield. The effect of bean fly infestation on yield when no nitrogen and phosphorus were applied, was a 48% reduction in yield, Therefore, the use of nitrogen and phosphorus fertilizers reduced the effect of bean fly damage and increased grain yield. Inter cropping increased bean fly infestation compared to pure stands of beans. The micro climatic conditions (light intensity, temperature and relative humidity) created by inter cropping of beans with maize increased bean fly infestation compared to that in the bean mono crop. Weeding regimes had no effect on bean fly infestation, however

Tolerance of different rice genotypes (oryza sativa l.) against the infestation of rice stem borers under natural field conditions

International Nuclear Information System (INIS)

Sarwar, M.; Ahmad, N.; Nasrullah; Tofique, M.

2010-01-01

The present studies report the genotypic responses of 61 rice (Oryza sativa L.) genotypes (35 aromatic and 26 non aromatic) against the infestation of rice stem borers under natural field conditions. The data obtained on these genotypes on larval infestation in combination with yield were the criteria to assess the resistance depicted by them. The studies showed that among aromatic genotypes, 'Khushboo-95' gave the best yield of grain and harboured the least pest infestation (2.81% dead hearts and 1.85% white heads); on the other hand variety 'Sonahri Sugdasi (P)' harboured the highest borers attack (10.37% and 19.30%) and yielded the lowest grain yield. Regarding non-aromatic genotypes, IR8-2.5-11 received least infestation (1.32% and 0.26% dead hearts and white heads, respectively) generating highest yield showing its tolerance to borer's attack, in contrast, genotype IR6-252 harboured the highest infestation (5.65%, 4.28%) and yielded minimum grain indicating its susceptibility. These results demonstrate the expression of resistance gene in the genome of tolerant rice genotypes that can provide season-long protection from the natural infestation of insect pests. (author)

Efficacy of a novel oral formulation of sarolaner (Simparica™) against five common tick species infesting dogs in the United States.

Science.gov (United States)

Six, Robert H; Everett, William R; Young, David R; Carter, Lori; Mahabir, Sean P; Honsberger, Nicole A; Myers, Melanie R; Holzmer, Susan; Chapin, Sara; Rugg, Jady J

2016-05-30

The efficacy of a single oral treatment with sarolaner (Simparica™, Zoetis), a novel isoxazoline compound, was evaluated against five tick species known to infest dogs in the United States. A total of 10 laboratory studies, two against each species, were conducted using adult purpose-bred mongrels or Beagle dogs. In each study, 16 dogs were randomly allocated to one of two treatment groups based on pre-treatment host-suitability tick counts. Dogs were infested with approximately 50 unfed adult Amblyomma americanum, Amblyomma maculatum, Dermacentor variabilis, Ixodes scapularis or Rhipicephalus sanguineus ticks on Days -2, 5, 12, 19, 26 and 33. On Day 0, dogs were treated with a placebo or a sarolaner tablet providing a minimum dose of 2 mg/kg. Tick counts were conducted 48h after treatment and after each subsequent weekly re-infestation. There were no treatment-related adverse reactions during any of the studies. Dogs in the placebo-treated group maintained tick infestations throughout the studies. Geometric mean live tick counts were significantly lower (P≤0.0001) in the sarolaner-treated group compared to the tick counts in the placebo group at all timepoints. Treatment with sarolaner resulted in ≥99.6% efficacy against existing infestations of all five tick species within 48h. The efficacy against weekly post-treatment re-infestations of all tick species was ≥96.9% for at least 35 days after treatment. Thus, a single dose of sarolaner administered orally at the minimum dosage of 2mg/kg, resulted in excellent efficacy within 48h against existing tick infestations, and against weekly re-infestations for 35 days after treatment. These studies confirmed that administration of the minimum dose of sarolaner will provide rapid treatment of existing infestations and give at least one month of control against re-infestation by the common tick species affecting dogs in the US. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Effect of a herbal compound for treatment of sarcoptic mange infestations on dogs.

Science.gov (United States)

Das, S S

1996-06-01

Charmil gel, a herbal product was tried against Sarcoptes scabei var canis on dogs and its efficacy was compared with that of amitraz. Mite scrapings examined at scheduled intervals after the topical application of Charmil gel caused complete recovery after 14 days in severe infestation and 7 to 10 days in mild to moderate infestations with regrowth of hair on Day 28 post-treatment. No adverse reactions were observed except mild irritation and restlessness, which persisted for a few hours soon after application.

Tamarisk (Salt Cedar) Infestations in Northwestern Nevada Mapped Using Landsat TM Imagery and GIS Layers

Science.gov (United States)

Sengupta, D.; Geraci, C.; Kolkowitz, S.

2004-12-01

Tamarisk, also known as salt cedar (Tamarix sp.) is a prevalent invasive species that has infested many riparian areas in the southwestern United States. Mature salt cedar plants are resistant to high stress environments and fare well in drought conditions, mainly due to their extensive root systems that derive much of their sustenance from the water table rather than surface water and precipitation. The salt cedar root systems have altered hydrological patterns by tapping into underlying aquifers. This has decreased water available for recreational use, regional ecology and plant diversity. Many states have implemented salt cedar monitoring programs at the local level, but the problem of large-scale mapping of this invasive species has continued to be a challenge to land management agencies. Furthermore, inaccessible and unexplored areas continue to be absent in the mapping process. In August 2004, using field data consisting of large areas as training sets for classification of Landsat TM imagery, the DEVELOP student research team at NASA Ames Research Center generated a preliminary map of areas that that were susceptible to salt cedar growth for a region in northwestern Nevada. In addition to the remote sensing-based classification of satellite imagery, the team used the variables of elevation and estimated distance to the water table in conjunction with collected field data and knowledge of salt cedar growth habits to further refine the map. The team has further extended the mapping of key environmental factors of water availability for salt cedar, soil types and species distribution in regions infested by salt cedar. The investigation was carried out by 1) improving an existing GIS layer for water access using a suitable interpolation method, 2) including a GIS layer for soils associated with salt cedar growth and 3) completing field work to evaluate species distribution and regions of presence or absence of salt cedar. The outcome of this project served to

Stochastic models for tumoral growth

Science.gov (United States)

Escudero, Carlos

2006-02-01

Strong experimental evidence has indicated that tumor growth belongs to the molecular beam epitaxy universality class. This type of growth is characterized by the constraint of cell proliferation to the tumor border and the surface diffusion of cells at the growing edge. Tumor growth is thus conceived as a competition for space between the tumor and the host, and cell diffusion at the tumor border is an optimal strategy adopted for minimizing the pressure and helping tumor development. Two stochastic partial differential equations are reported in this paper in order to correctly model the physical properties of tumoral growth in (1+1) and (2+1) dimensions. The advantage of these models is that they reproduce the correct geometry of the tumor and are defined in terms of polar variables. An analysis of these models allows us to quantitatively estimate the response of the tumor to an unfavorable perturbation during growth.

Latent Growth and Dynamic Structural Equation Models.

Science.gov (United States)

Grimm, Kevin J; Ram, Nilam

2018-05-07

Latent growth models make up a class of methods to study within-person change-how it progresses, how it differs across individuals, what are its determinants, and what are its consequences. Latent growth methods have been applied in many domains to examine average and differential responses to interventions and treatments. In this review, we introduce the growth modeling approach to studying change by presenting different models of change and interpretations of their model parameters. We then apply these methods to examining sex differences in the development of binge drinking behavior through adolescence and into adulthood. Advances in growth modeling methods are then discussed and include inherently nonlinear growth models, derivative specification of growth models, and latent change score models to study stochastic change processes. We conclude with relevant design issues of longitudinal studies and considerations for the analysis of longitudinal data.

Testing mechanistic models of growth in insects.

Science.gov (United States)

Maino, James L; Kearney, Michael R

2015-11-22

Insects are typified by their small size, large numbers, impressive reproductive output and rapid growth. However, insect growth is not simply rapid; rather, insects follow a qualitatively distinct trajectory to many other animals. Here we present a mechanistic growth model for insects and show that increasing specific assimilation during the growth phase can explain the near-exponential growth trajectory of insects. The presented model is tested against growth data on 50 insects, and compared against other mechanistic growth models. Unlike the other mechanistic models, our growth model predicts energy reserves per biomass to increase with age, which implies a higher production efficiency and energy density of biomass in later instars. These predictions are tested against data compiled from the literature whereby it is confirmed that insects increase their production efficiency (by 24 percentage points) and energy density (by 4 J mg(-1)) between hatching and the attainment of full size. The model suggests that insects achieve greater production efficiencies and enhanced growth rates by increasing specific assimilation and increasing energy reserves per biomass, which are less costly to maintain than structural biomass. Our findings illustrate how the explanatory and predictive power of mechanistic growth models comes from their grounding in underlying biological processes. © 2015 The Author(s).

Delusional infestation with unusual pathogens: a report of three cases.

Science.gov (United States)

Dewan, P; Miller, J; Musters, C; Taylor, R E; Bewley, A P

2011-10-01

Delusional infestation (DI) is a psychiatric disorder characterized by a fixed, false belief that the patient is infested with extracorporeal agents. It is known by several names, including the more commonly used term 'delusional parasitosis'. The psychiatric disease is responsible for the cutaneous pathology. About 90% of patients with DI seek help from dermatologists, and most reject psychiatric referral. Thus, effective management requires incorporation of psychiatric principles. We report three cases of DI with inanimate materials, and examine 'Morgellons' disease. We believe that patients with unusual presentations of DI are likely to be seen more commonly in the future. These patients appear to be a subgroup of DI, and may be even more difficult to treat than other patients with DI. © The Author(s). CED © 2011 British Association of Dermatologists.

Biocontrol of certain soilborne diseases and promotion of growth of capsicum annuum using biofungicides

International Nuclear Information System (INIS)

Madbouly, A.; Abdelbacki, A.M.M.

2017-01-01

Colored pepper (Capsicum annuum L.) has great economic importance as a food vegetable crop in Egypt and all over the world. This crop is prone to infection with soilborne fungal pathogens such as Rhizoctonia solani, Fusarium solani and Macrophomina phaseolina. These mycopathogens were isolated from diseased pepper seedlings, identified; their virulence was confirmed in the greenhouse. Eight bacterial isolates mainly; (Bacillus subtilis and Pseudomonas fluorescens), and many fungal isolates mainly, (Trichoderma harzianum and T. viride), were isolated from the rhizosphere soil of pepper. They caused appreciable In vitro inhibition of the radial growth of the 3 pathogens in dual culture technique, in percentages ranging from (71-79%) and (80-87%), respectively. On infestation of pepper soil with these bioagents and the 3 pathogens separately in the greenhouse, they caused In vivo reduction of disease symptoms of pepper compared with the pathogens infested and non-infested control soils. In addition, they caused significant improvement of pepper growth compared with the control soil, however, promotion exerted by B. subtilis and T. harzianum was more than that of P. fluorescens and T. viride. These promoting activities could be attributed to the production of metabolites such as growth hormones; solubilization of phosphates and improvement of nutrient uptake. This is the first record of promoting the growth of pepper in greenhouse by B. subtilis and T. harzianum in Egypt. Thus these bioagents could be formulated then applied in the future in pepper fields of this country as safe, effective, ecofriendly biofungicides to control soilborne pathogens and also could be used as biofertilizers to promote the growth and productivity of this crop. (author)

Brown dog tick, Rhipicephalus sanguineus sensu lato, infestation of susceptible dog hosts is reduced by slow release of semiochemicals from a less susceptible host.

Science.gov (United States)

de Oliveira Filho, Jaires Gomes; Ferreira, Lorena Lopes; Sarria, André Lucio Franceschini; Pickett, John A; Birkett, Michael A; Mascarin, Gabriel Moura; de León, Adalberto A Pérez; Borges, Lígia Miranda Ferreira

2017-01-01

Domestic dog breeds are hosts for the brown dog tick, Rhipicephalus sanguineus sensu lato, but infestation levels vary among breeds. Beagles are less susceptible to tick infestations than English cocker spaniels due to enhanced production of 2-hexanone and benzaldehyde that act as volatile tick repellents. We report the use of prototype slow-release formulations of these compounds to reduce the burden of R. sanguineus s. l. on English cocker spaniel dogs. Twelve dogs were randomly assigned to two groups with six dogs each. The treated group received collars with slow-release formulations of the compounds attached, while the control group received collars with clean formulations attached. Five environmental infestations were performed, with the number of ticks (at all stages) on the dogs being counted twice a day for 45days. The counts on the number of tick stages found per dog were individually fitted to linear mixed effects models with repeated measures and normal distribution for errors. The mean tick infestation in the treated group was significantly lower than in the control group. For larvae and nymphs, a decrease in tick infestation was observed at the fifth count, and for adults, lower average counts were observed in all counts. The compounds did not interfere with the distribution of the ticks on the body of the dogs, as a similar percentage of ticks was found on the anterior half of the dogs (54.5% for the control group and 56.2% for the treated group). The biological and reproductive parameters of the ticks were not affected by the repellents. This study highlights for the first time the potential use of a novel allomone (repellent)-based formulation for reduction of tick infestation on susceptible dogs. Copyright © 2016 Elsevier GmbH. All rights reserved.

Importance of husk covering on field infestation of maize by ...

African Journals Online (AJOL)

STORAGESEVER

2008-10-20

Oct 20, 2008 ... An experiment was conducted to determine the importance of husk covering on field infestation of maize by the maize ... high yielding plants with no consideration for resistance ..... provided financial support for the study.

How fast will trees die? A transition matrix model of ash decline in forest stands infested by emerald ash borer

Science.gov (United States)

Kathleen S. Knight; Robert P. Long; Joanne Rebbeck; Annemarie Smith; Kamal Gandhi; Daniel A. Herms

2008-01-01

We recorded Fraxinus spp. tree health and other forest stand characteristics for 68 plots in 21 EAB-infested forest stands in Michigan and Ohio in 2005 and 2007. Fraxinus spp. were a dominant component of these stands, with more than 900 ash trees (including Fraxinus americana, Fraxinus pennsylvanica, Fraxinus profunda...

Skin infections and infestations in prison inmates.

Science.gov (United States)

Oninla, Olumayowa A; Onayemi, Olaniyi

2012-02-01

Skin infections and infestations are common in a prison environment. The prison is in dynamic equilibrium with the larger society. Hence, it serves as a reservoir of infections which can spread to the larger society. The study sets out to find out how rampant these infections might be in the prison and the factors responsible. Inmates at a Nigerian prison in Ilesha, Osun State, were examined for skin infections. Personal hygiene and living conditions were critically examined. The overall prevalent rate of infectious dermatoses was 49.2% (150/305). There were 178 infections. Dermatophytes accounted for 64%, pityriasis versicolor 27%, bacterial infections 3.4%, and others 5.6%. Only frequency of soap use and accommodation arrangement significantly contributed to the overall prevalence. However, infectious dermatoses were significantly affected by prison status (PP = 0.04), frequency of bath (PP = 0.025), changing of clothing (PP = 0.05), accommodation arrangement (P = 0.0001), frequency of soap usage (P = 0.005), and toilet facility (P = 0.001). The HIV status of the inmates was unknown. Hence, effect of HIV infection cannot be ascertained. Skin infections and infestations are common in prison. A change in living conditions and personal hygiene will definitely help in reducing these infections. © 2012 The International Society of Dermatology.

Layered growth model and epitaxial growth structures for SiCAlN alloys

International Nuclear Information System (INIS)

Liu Zhaoqing; Ni Jun; Su Xiaoao; Dai Zhenhong

2009-01-01

Epitaxial growth structures for (SiC) 1-x (AlN) x alloys are studied using a layered growth model. First-principle calculations are used to determine the parameters in the layered growth model. The phase diagrams of epitaxial growth are given. There is a rich variety of the new metastable polytype structures at x=1/6 ,1/5 ,1/4 ,1/3 , and 1/2 in the layered growth phase diagrams. We have also calculated the electronic properties of the short periodical SiCAlN alloys predicted by our layered growth model. The results show that various ordered structures of (SiC) 1-x (AlN) x alloys with the band gaps over a wide range are possible to be synthesized by epitaxial growth.

Comparative Proteomic Analysis of Susceptible and Resistant Rice Plants during Early Infestation by Small Brown Planthopper

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Yan Dong

2017-10-01

Full Text Available The small brown planthopper (Laodelphax striatellus Fallén, Homoptera, Delphacidae-SBPH is one of the major destructive pests of rice (Oryza sativa L.. Understanding on how rice responds to SBPH infestation will contribute to developing strategies for SBPH control. However, the response of rice plant to SBPH is poorly understood. In this study, two contrasting rice genotypes, Pf9279-4 (SBPH-resistant and 02428 (SBPH-susceptible, were used for comparative analysis of protein profiles in the leaf sheath of rice plants in responses to SBPH infestation. One hundred and thirty-two protein spots that were differentially expressed between the resistant and susceptible rice lines were identified with significant intensity differences (≥2-fold, P < 0.05 at 0, 6, and 12 h after SBPH infestation. Protein expression profile analysis in the leaf sheath of SBPH-resistant and SBPH-susceptible rice lines after SBPH infestation showed that proteins induced by SBPH feeding were involved mainly in stress response, photosynthesis, protein metabolic process, carbohydrate metabolic process, energy metabolism, cell wall-related proteins, amino acid metabolism and transcriptional regulation. Gene expression analysis of 24 differentially expressed proteins (DEPs showed that more than 50% DEPs were positively correlated with their mRNA levels. Analysis of some physiological indexes mainly involved in the removal of oxygen reactive species showed that the levels of superoxide dismutase (SOD and glutathione (GSH were considerably higher in Pf9279-4 than 02428 during SBPH infestation. The catalase (CAT activity and hydroxyl radical inhibition were lower in Pf9279-4 than 02428. Analysis of enzyme activities indicates that Pf9279-4 rice plants defend against SBPH through the activation of the pathway of the salicylic acid (SA-dependent systemic acquired resistance. In conclusion, this study provides some insights into the molecular networks involved on cellular and

Stochastic ontogenetic growth model

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West, B. J.; West, D.

2012-02-01

An ontogenetic growth model (OGM) for a thermodynamically closed system is generalized to satisfy both the first and second law of thermodynamics. The hypothesized stochastic ontogenetic growth model (SOGM) is shown to entail the interspecies allometry relation by explicitly averaging the basal metabolic rate and the total body mass over the steady-state probability density for the total body mass (TBM). This is the first derivation of the interspecies metabolic allometric relation from a dynamical model and the asymptotic steady-state distribution of the TBM is fit to data and shown to be inverse power law.

Scabies Mites Alter the Skin Microbiome and Promote Growth of Opportunistic Pathogens in a Porcine Model

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Swe, Pearl M.; Zakrzewski, Martha; Kelly, Andrew; Krause, Lutz; Fischer, Katja

2014-01-01

Background The resident skin microbiota plays an important role in restricting pathogenic bacteria, thereby protecting the host. Scabies mites (Sarcoptes scabiei) are thought to promote bacterial infections by breaching the skin barrier and excreting molecules that inhibit host innate immune responses. Epidemiological studies in humans confirm increased incidence of impetigo, generally caused by Staphylococcus aureus and Streptococcus pyogenes, secondary to the epidermal infestation with the parasitic mite. It is therefore possible that mite infestation could alter the healthy skin microbiota making way for the opportunistic pathogens. A longitudinal study to test this hypothesis in humans is near impossible due to ethical reasons. In a porcine model we generated scabies infestations closely resembling the disease manifestation in humans and investigated the scabies associated changes in the skin microbiota over the course of a mite infestation. Methodology/Principal Findings In a 21 week trial, skin scrapings were collected from pigs infected with S. scabies var. suis and scabies-free control animals. A total of 96 skin scrapings were collected before, during infection and after acaricide treatment, and analyzed by bacterial 16S rDNA tag-encoded FLX-titanium amplicon pyrosequencing. We found significant changes in the epidermal microbiota, in particular a dramatic increase in Staphylococcus correlating with the onset of mite infestation in animals challenged with scabies mites. This increase persisted beyond treatment from mite infection and healing of skin. Furthermore, the staphylococci population shifted from the commensal S. hominis on the healthy skin prior to scabies mite challenge to S. chromogenes, which is increasingly recognized as being pathogenic, coinciding with scabies infection in pigs. In contrast, all animals in the scabies-free cohort remained relatively free of Staphylococcus throughout the trial. Conclusions/Significance This is the first

Scabies mites alter the skin microbiome and promote growth of opportunistic pathogens in a porcine model.

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Pearl M Swe

Full Text Available BACKGROUND: The resident skin microbiota plays an important role in restricting pathogenic bacteria, thereby protecting the host. Scabies mites (Sarcoptes scabiei are thought to promote bacterial infections by breaching the skin barrier and excreting molecules that inhibit host innate immune responses. Epidemiological studies in humans confirm increased incidence of impetigo, generally caused by Staphylococcus aureus and Streptococcus pyogenes, secondary to the epidermal infestation with the parasitic mite. It is therefore possible that mite infestation could alter the healthy skin microbiota making way for the opportunistic pathogens. A longitudinal study to test this hypothesis in humans is near impossible due to ethical reasons. In a porcine model we generated scabies infestations closely resembling the disease manifestation in humans and investigated the scabies associated changes in the skin microbiota over the course of a mite infestation. METHODOLOGY/PRINCIPAL FINDINGS: In a 21 week trial, skin scrapings were collected from pigs infected with S. scabies var. suis and scabies-free control animals. A total of 96 skin scrapings were collected before, during infection and after acaricide treatment, and analyzed by bacterial 16S rDNA tag-encoded FLX-titanium amplicon pyrosequencing. We found significant changes in the epidermal microbiota, in particular a dramatic increase in Staphylococcus correlating with the onset of mite infestation in animals challenged with scabies mites. This increase persisted beyond treatment from mite infection and healing of skin. Furthermore, the staphylococci population shifted from the commensal S. hominis on the healthy skin prior to scabies mite challenge to S. chromogenes, which is increasingly recognized as being pathogenic, coinciding with scabies infection in pigs. In contrast, all animals in the scabies-free cohort remained relatively free of Staphylococcus throughout the trial. CONCLUSIONS

Study of the infestation rate of the kidney and spleen of domestic ruminants by Linguatula serrata nymphs in Urmia slaughterhouse

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S Rasouli

2009-02-01

Full Text Available In this study, the prevalence of Linguatula serrata nymphs in kidneys and spleens of 800 domestic ruminants (cattle, buffalo, sheep and goat in different sexes, ages and seasons was investigated. First, the kidneys and spleens were examined macroscopically. Then, a digestion method was also applied. Infestation rate in the spleen of cattle, buffalo, sheep and goat were %0/5, %0, %0/5 and %1/5 respectively. No infestation was found in the kidneys. The results of this study shows that the infestation of domestic ruminants to Linguatula serrat nymphs in different sexes and ages were not significant. Also the infestation rate in different seasons was not significant.

Prevalence of intestinal parasitic infestation in HIV seropositive and ...

African Journals Online (AJOL)

opportunistic parasites such as Cryptosporidium,. Cyclospora and Isospora species. It is also important to note that this report will be the first documentation on HIV/AIDS and intestinal parasites from this center. And it aims to determine the frequency and pattern of intestinal parasitic infestation, including protozoan species ...

Postharvest tillage reduces Downy Brome infestations in winter wheat

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In the Pacific Northwest, downy brome continues to infest winter wheat producing regions especially in low-rainfall areas where the winter wheat-summer fallow rotation is the dominate production system. In Washington, a study was conducted for 2 years at each of two locations in the winter wheat -su...

Lynxacarus radovskyi mites in feral cats: a study of diagnostic methods, preferential body locations, co-infestations and prevalence.

Science.gov (United States)

Ketzis, Jennifer K; Dundas, James; Shell, Linda G

2016-10-01

Lynxacarus radovskyi (fur mites) are ectoparasites found on the hair shafts of cats living in tropical environments. Diagnosis is via microscopic examination of hairs. Various anatomical areas have been reported to harbour these mites. To assess adhesive tape impressions and trichograms for detecting L. radovskyi and co-infestations; to determine host body predilection sites and affected gender; to determine prevalence of L. radovskyi in a feral cat population. 121 feral cats in a trap, neuter and release programme. After cats were premedicated for surgical sterilization, hairs from seven to nine body sites were removed from each cat using adhesive tape impression and trichogram techniques. Samples were examined at 10-100× magnification using compound or stereo microscopes. The prevalence of L. radovskyi was 71% (86 of 121) within the feral cat population. Tape impressions identified 75 cats; trichograms identified 56 cats. There were fewer false negative results with tape impressions. Caudal body sites were more likely to be positive, with the perianal area being the most commonly affected. Males and females were infested equally. Tape impressions identified more Cheyletiella blakei infestations and both methods identified some Felicola felis infestations. Tape impressions were easier to perform and identified more L. radovskyi positive cats and more co-infestations. Hairs from the perianal area and other caudal body sites are most likely to harbour L. radovskyi. Within this feral cat population, L. radovskyi was a common infestation. © 2016 ESVD and ACVD.

Role of Blossoms in Watermelon Seed Infestation by Acidovorax avenae subsp. citrulli.

Science.gov (United States)

Walcott, R R; Gitaitis, R D; Castro, A C

2003-05-01

ABSTRACT The role of watermelon blossom inoculation in seed infestation by Acidovorax avenae subsp. citrulli was investigated. Approximately 98% (84/87) of fruit developed from blossoms inoculated with 1 x 10(7) or 1 x 10(9) CFU of A. avenae subsp. citrulli per blossom were asymptomatic. Using immunomagnetic separation and the polymerase chain reaction, A. avenae subsp. citrulli was detected in 44% of the seed lots assayed, despite the lack of fruit symptoms. Furthermore, viable colonies were recovered from 31% of the seed lots. Of these lots, 27% also yielded seedlings expressing bacterial fruit blotch symptoms when planted under conditions of 30 degrees C and 90% relative humidity. A. avenae subsp. citrulli was detected and recovered from the pulp of 33 and 19%, respectively, of symptomless fruit whose blossoms were inoculated with A. avenae subsp. citrulli. The ability to penetrate watermelon flowers was not unique to A. avenae subsp. citrulli, because blossoms inoculated with Pantoea ananatis also resulted in infested seed and pulp. The data indicate that watermelon blossoms are a potential site of ingress for fruit and seed infestation by A. avenae subsp. citrulli.

Intercropping System for Protection the Potato Plant from Insect Infestation

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Aziza Sharaby

2015-06-01

Full Text Available The use of intercropping system provides an option for insect control for organic farmers that are limited in their chemical use. Additionally, intercropping systems can be attractive to conventional growers as a cost-effective insect control solution. A study was carried out for two seasons 2011-2012 and 2012-2013 to evaluate the effect of intercropping of potato (Solanum tuberosum L. with onion (Allium cepa L. on whitefly (Bemicia tabasi Gennadius and aphids’ Myzus persicae Sulz. and Aphis gossypii Glover infestation in potato fields. Results indicated that intercropping significantly reduced potato plant infestation with whitefly by 42.7, 51.3% while it was 62.69% reduction with aphids during the two successive winter seasons than when potato plants were cultivated alone. Therefore, intercropping could be recommended as a protection method of reducing pest population in the fields.

Ionizing radiation as a phytosanitary treatment against fruit flies (Diptera: Tephritidae): Efficacy in naturally versus artificially infested fruit

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Some phytosanitary irradiation treatments against tephritid fruit flies have been developed using artificial infestation of fruit without first comparing its effect on efficacy. In this study, efficacy was compared using infestation of grapefruit with Mexican fruit fly, Anastrepha ludens (Loew), vi...

Pre-infestation of Tomato Plants by Aphids Modulates Transmission-Acquisition Relationship among Whiteflies, Tomato Yellow Leaf Curl Virus (TYLCV and Plants

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Xiao L. Tan

2017-09-01

Full Text Available Herbivory defense systems in plants are largely regulated by jasmonate-(JA and salicylate-(SA signaling pathways. Such defense mechanisms may impact insect feeding dynamic, may also affect the transmission-acquisition relationship among virus, plants and vectoring insects. In the context of the tomato – whitefly – Tomato Yellow Leaf Curl Virus (TYLCV biological model, we tested the impact of pre-infesting plants with a non-vector insect (aphid Myzus persicae on feeding dynamics of a vector insect (whitefly Bemisia tabaci as well as virus transmission-acquisition. We showed that an aphid herbivory period of 0–48 h led to a transient systemic increase of virus concentration in the host plant (root, stem, and leaf, with the same pattern observed in whiteflies feeding on aphid-infested plants. We used real-time quantitative PCR to study the expression of key genes of the SA- and JA-signaling pathways, as well as electrical penetration graph (EPG to characterize the impact of aphid pre-infestation on whitefly feeding during TYLCV transmission (whitefly to tomato and acquisition (tomato to whitefly. The impact of the duration of aphid pre-infestation (0, 24, or 48 h on phloem feeding by whitefly (E2 during the transmission phase was similar to that of global whitefly feeding behavior (E1, E2 and probing duration during the acquisition phase. In addition, we observed that a longer phase of aphid pre-infestation prior to virus transmission by whitefly led to the up-regulation and down-regulation of SA- and JA-signaling pathway genes, respectively. These results demonstrated a significant impact of aphid pre-infestation on the tomato – whitefly – TYLCV system. Transmission and acquisition of TYLCV was positively correlated with feeding activity of B. tabaci, and both were mediated by the SA- and JA-pathways. TYLCV concentration during the transmission phases was modulated by up- and down-regulation of SA- and JA-pathways, respectively. The two

Rabbit management and occurrences of mange mite infestations in ...

African Journals Online (AJOL)

A cross-sectional study was conducted in Morogoro Municipality between September and December 2015 to explore the rabbit farming and assess the common health problems with a focus on epidemiology of mange infestation. A total of 18 rabbit farms with 622 animals from 9 wards were investigated. A questionnaire ...

Infestation and morphological identification of the stalked epizoic barnacle Octolasmis on the blue crab Portunus pelagicus from the Red Sea

Science.gov (United States)

Afifi Khattab, Rafat

2017-09-01

The intensity of infestation of the epizoic stalked barnacle Octolasmis on the blue crab was calculated for a total of 180 individuals collected around Jeddah, the western Red Sea Saudi coast. More than 90% of the crabs were found bearing the Octolasmis at a prevalence rate of 92% and mean intensity of 18.5±18.6 (0-127 epibiont per host). The intensity of infestation increased with host size in the range 90-135 mm. Generally, females were more infested (69%) than the males (31%). Octolasmis angulata occurred mostly on the gills, and the lower side of the gill chambers was more infested (84%) than the upper side (16%) and the left side of gills was also more infested than the right side in both males and females. Further studies are still needed to examine the commensal relationship and its impact on the fishery market of the Red Sea blue crab populations.

Increased gum arabic production after infestation of Acacia senegal ...

African Journals Online (AJOL)

The aim of this study was to investigate the correlation between the beetle Agrilus nubeculosus and gum arabic production by Acacia senegal. Some trees were tapped and left open to facilitate infestation by A. nubeculosus and others were covered with wire mesh as control. Gum yield, physical and chemical properties of ...

On a Versatile Stochastic Growth Model

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Samiur Arif

2012-06-01

Full Text Available Growth phenomena are ubiquitous and pervasive not only in biology and the medical sciences, but also in economics, marketing and the computer and social sciences. We introduce a three-parameter version of the classic pure-birth process growth model when suitably instantiated, can be used to model growth phenomena in many seemingly unrelated application domains. We point out that the model is computationally attractive since it admits of conceptually simple, closed form solutions for the time-dependent probabilities.

Viscoelastic model of tungsten 'fuzz' growth

International Nuclear Information System (INIS)

Krasheninnikov, S I

2011-01-01

A viscoelastic model of fuzz growth is presented. The model describes the main features of tungsten fuzz observed in experiments. It gives estimates of fuzz growth rate and temperature range close to experimental ones.

9 CFR 72.21 - Animals infested with or exposed to ticks subject to same restrictions as cattle.

Science.gov (United States)

2010-01-01

... ticks subject to same restrictions as cattle. 72.21 Section 72.21 Animals and Animal Products ANIMAL AND... (INCLUDING POULTRY) AND ANIMAL PRODUCTS TEXAS (SPLENETIC) FEVER IN CATTLE § 72.21 Animals infested with or exposed to ticks subject to same restrictions as cattle. Animals other than cattle which are infested with...

Ticks and Fleas Infestation on East Hedgehogs (Erinaceus concolor in Van Province, Eastern Region of Turkey

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Yaşar Goz

2015-10-01

Full Text Available Background: Ixodid ticks (Acari: İxodidae and fleas (Siphonaptera are the major vectors of pathogens threatening animals and human healths. The aim of our study was to detect the infestation rates of East Hedgehogs (Erinaceus concolor with ticks and fleas in Van Province, eastern region of Turkey.Methods: We examined fleas and ticks infestation patterns in 21 hedgehogs, collected from three suburbs with the greater of number gardens. In order to estimate flea and tick infestation of hedgehogs, we immobilized the ectoparasites by treatment the body with a insecticide trichlorphon (Neguvon®-Bayer.Results: On the hedgehogs, 60 ixodid ticks and 125 fleas were detected. All of the ixodid ticks were Rhipicephalus turanicus and all of the fleas were Archaeopsylla erinacei. Infestation rate for ticks and fleas was detected 66.66 % and 100 %, respectively.Conclusion: We detected ticks (R. turanicus and fleas (A. erinacei in hedgehogs at fairly high rates. Since many ticks and fleas species may harbor on hedgehogs and transmit some tick-borne and flea-borne patogens, this results are the important in terms of veterinary and public health. 

Mathematical modeling of microbial growth in milk

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Jhony Tiago Teleken

2011-12-01

Full Text Available A mathematical model to predict microbial growth in milk was developed and analyzed. The model consists of a system of two differential equations of first order. The equations are based on physical hypotheses of population growth. The model was applied to five different sets of data of microbial growth in dairy products selected from Combase, which is the most important database in the area with thousands of datasets from around the world, and the results showed a good fit. In addition, the model provides equations for the evaluation of the maximum specific growth rate and the duration of the lag phase which may provide useful information about microbial growth.

Winter Survival of Individual Honey Bees and Honey Bee Colonies Depends on Level of Varroa destructor Infestation

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van Dooremalen, Coby; Gerritsen, Lonne; Cornelissen, Bram; van der Steen, Jozef J. M.; van Langevelde, Frank; Blacquière, Tjeerd

2012-01-01

Background Recent elevated winter loss of honey bee colonies is a major concern. The presence of the mite Varroa destructor in colonies places an important pressure on bee health. V. destructor shortens the lifespan of individual bees, while long lifespan during winter is a primary requirement to survive until the next spring. We investigated in two subsequent years the effects of different levels of V. destructor infestation during the transition from short-lived summer bees to long-lived winter bees on the lifespan of individual bees and the survival of bee colonies during winter. Colonies treated earlier in the season to reduce V. destructor infestation during the development of winter bees were expected to have longer bee lifespan and higher colony survival after winter. Methodology/Principal Findings Mite infestation was reduced using acaricide treatments during different months (July, August, September, or not treated). We found that the number of capped brood cells decreased drastically between August and November, while at the same time, the lifespan of the bees (marked cohorts) increased indicating the transition to winter bees. Low V. destructor infestation levels before and during the transition to winter bees resulted in an increase in lifespan of bees and higher colony survival compared to colonies that were not treated and that had higher infestation levels. A variety of stress-related factors could have contributed to the variation in longevity and winter survival that we found between years. Conclusions/Significance This study contributes to theory about the multiple causes for the recent elevated colony losses in honey bees. Our study shows the correlation between long lifespan of winter bees and colony loss in spring. Moreover, we show that colonies treated earlier in the season had reduced V. destructor infestation during the development of winter bees resulting in longer bee lifespan and higher colony survival after winter. PMID:22558421

Exuberant granulation tissue response associated with Neobenedenia sp. (Monogenea: Capsalidae) infestation in two cobia, Rachycentron canadum (Linnaeus).

Science.gov (United States)

Hurley-Sanders, J; Harms, C; Christiansen, E; Clarke, E; Law, J

2016-03-01

Monogenean parasite infestations are common in captive marine teleosts, and are generally found on the skin and gills. This report describes an unusual pathological presentation of exuberant granulation tissue of the gills, suspected to be related to Neobenedenia infestation in two cobia housed together at a North Carolina aquarium. © 2015 John Wiley & Sons Ltd.

Aboveground Whitefly Infestation Modulates Transcriptional Levels of Anthocyanin Biosynthesis and Jasmonic Acid Signaling-Related Genes and Augments the Cope with Drought Stress of Maize.

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Yong-Soon Park

Full Text Available Up to now, the potential underlying molecular mechanisms by which maize (Zea mays L. plants elicit defense responses by infestation with a phloem feeding insect whitefly [Bemisia tabaci (Genn.] have been barely elucidated against (abiotic stresses. To fill this gap of current knowledge maize plants were infested with whitefly and these plants were subsequently assessed the levels of water loss. To understand the mode of action, plant hormone contents and the stress-related mRNA expression were evaluated. Whitefly-infested maize plants did not display any significant phenotypic differences in above-ground tissues (infested site compared with controls. By contrast, root (systemic tissue biomass was increased by 2-fold by whitefly infestation. The levels of endogenous indole-3-acetic acid (IAA, jasmonic acid (JA, and hydrogen peroxide (H2O2 were significantly higher in whitefly-infested plants. The biosynthetic or signaling-related genes for JA and anthocyanins were highly up-regulated. Additionally, we found that healthier plants were obtained in whitefly-infested plants under drought conditions. The weight of whitefly-infested plants was approximately 20% higher than that of control plants at 14 d of drought treatment. The drought tolerance-related genes, ZmbZIP72, ZmSNAC1, and ZmABA1, were highly expressed in the whitefly-infected plants. Collectively, our results suggest that IAA/JA-derived maize physiological changes and correlation of H2O2 production and water loss are modulated by above-ground whitefly infestation in maize plants.

Charring does not affect wood infestation by subterranean termites

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C.J. Peterson; P.D. Gerard; T.L. Wagner

2007-01-01

Fire is an important part of forest ecosystems, as is the insect fauna. Changes in wood brought aboutby fire may alter the ability of termites to use the wood, interrupting the decay cycle of woody debris.The ability of termites to find, infest, and feed upon wood after it had been charred was evaluated in

Does the removal of mite-infested brood facilitate grooming?

Science.gov (United States)

The relationship between the removal of mite-infested brood and mite drop was compared using Russian (RHB, n = 9) and Italian (IHB, n = 9) honey bee colonies. A cloake board was used to isolate test brood frame on the top hive body and the metal sheet served as a varroa trap. Inoculum mites were col...

Effects of Ionizing Radiation on Surface Infesting Microbes of Stored Grain

International Nuclear Information System (INIS)

Maity, J.P.; Chanda, S.; Chakraborty, A.; Santra, S.C.

2005-09-01

Spoilage of nutritional value of stored grains and seeds by the surface-infesting microbes, especially those producing mycotoxins, has been a worldwide economic problem. In this perspective our present work aims at probing into the potential of gamma rays to reduce the microbial infestation on stored grain surface and additionally to focus differential radiation sensitivity, if any, of the different fungi in response to gradient of gamma exposure. Co-60 source at 250 C emitting gamma rays at 1173 and 1332 keV energy (0.12 kGy/h) was used in the range of 0.5-6 kGy (absorbed dose) for irradiating some common stored seeds in India namely rice (Oryza sativa. Cv-2233 and Oryza sativa. Cv-Shankar), Bengal gram (Cicer arietinum. Cv-local), wheat (Triticum aestivum) and Mung (Phaseolus mungo). Gamma irradiation results in dose-dependent delay in colony formation and growth inhibition of the fungi on the seed surface. Differential rate of depletion was noted for different fungi. Effective absorbed dose for depletion of Alternaria sp., Aspergillus sp was 1 to 2 kGy while that for Tricoderma sp., Curvularia sp was 0.5-1 kGy. Complete inhibition of all the selected fungi was found above 2.5 kGy. Germinating potential of the irradiated grains remained unaffected upto an absorbed dose of 2kGy while their respective nutritional value in terms of protein and carbohydrate content was not significantly altered. Higher doses of exposure however, documented delayed seed germination. Colony forming ability (CFA) of the exposed fungi documented significant variation between fungi attached to the seed surface and that when isolated from the host. Alternaria sp, Aspergillus sp or Curvularia sp exhibited total inhibition of CFA at a much lower dose (1-3 kGy) in isolated conditions than that when seed attached (>4kGy). On the other hand Trichoderma sp expressed a different trend revealing more sensitivity in seed attached condition. Such differential response possibly reflects species

Ocular leech infestation

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Lee YC

2015-02-01

Full Text Available Yueh-Chang Lee, Cheng-Jen Chiu Department of Ophthalmology, Buddhist Tzu-Chi General Hospital, Hualien, Taiwan, ROC Abstract: This case report describes a female toddler with manifestations of ocular leech infestation. A 2-year-old girl was brought to our outpatient clinic with a complaint of irritable crying after being taken to a stream in Hualien 1 day previous, where she played in the water. The parents noticed that she rubbed her right eye a lot. Upon examination, the girl had good fix and follow in either eye. Slit-lamp examination showed conjunctival injection with a moving dark black–brown foreign body partly attached in the lower conjunctiva. After applying topical anesthetics, the leech, measuring 1 cm in length, was extracted under a microscope. The patient began using topical antibiotic and corticosteroid agents. By 1 week after extraction, the patient had no obvious symptoms or signs, except for a limited subconjunctival hemorrhage, and no corneal/scleral involvement was observed. Keywords: leech, ocular foreign body, conjunctival reaction, pediatric ophthalmology

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

Directory of Open Access Journals (Sweden)

Changlu Wang

2011-04-01

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

Dynamics of Haematobia irritans irritans (Diptera: Muscidae infestation on Nelore cattle in the Pantanal, Brazil

Directory of Open Access Journals (Sweden)

Barros Antonio Thadeu M

2001-01-01

Full Text Available From June 1993 to May 1995, horn fly counts were conducted twice a month on untreated Nelore cattle raised extensively in the Pantanal. Horn fly population showed a bimodal fluctuation and peaks were observed every year after the beginning (November/December and at the end (May/June of the rainy season, which coincided with mid-late spring and mid-late fall, respectively. Horn flies were present on cattle throughout the year in at least 64% of the animals. Mean horn fly numbers on animals did not exceed 85 flies/cow during peaks and were under 35 flies/cow in most of the remaining periods. The highest infestations (population peaks were short and dropped suddenly within two weeks. Less than 15% of the animals in both herds could be considered as "fly-susceptible" - showing consistently higher infestations, or "fly-resistant" - showing consistently lower infestations.

Influence of storage on fungal infestation in spices

International Nuclear Information System (INIS)

Akhtar, T.; Sattar, A.; Khan, I.

1988-01-01

The present work was carried out to study the influence of storage and gamma radiation on fungal control in spices. The spices were irradiated with 5.0, 7.5 and 10.0 KGy and stored under ambient conditions for 12 months. Fungal infestation decreased to undetectable levels upon irradiation of these spices especially at higher doses and increased with advanced storage period both the irradiated and unirradiated samples. (orig. /A.B.)

Parasite spread at the domestic animal - wildlife interface: anthropogenic habitat use, phylogeny and body mass drive risk of cat and dog flea (Ctenocephalides spp.) infestation in wild mammals.

Science.gov (United States)

Clark, Nicholas J; Seddon, Jennifer M; Šlapeta, Jan; Wells, Konstans

2018-01-08

Spillover of parasites at the domestic animal - wildlife interface is a pervasive threat to animal health. Cat and dog fleas (Ctenocephalides felis and C. canis) are among the world's most invasive and economically important ectoparasites. Although both species are presumed to infest a diversity of host species across the globe, knowledge on their distributions in wildlife is poor. We built a global dataset of wild mammal host associations for cat and dog fleas, and used Bayesian hierarchical models to identify traits that predict wildlife infestation probability. We complemented this by calculating functional-phylogenetic host specificity to assess whether fleas are restricted to hosts with similar evolutionary histories, diet or habitat niches. Over 130 wildlife species have been found to harbour cat fleas, representing nearly 20% of all mammal species sampled for fleas. Phylogenetic models indicate cat fleas are capable of infesting a broad diversity of wild mammal species through ecological fitting. Those that use anthropogenic habitats are at highest risk. Dog fleas, by contrast, have been recorded in 31 mammal species that are primarily restricted to certain phylogenetic clades, including canids, felids and murids. Both flea species are commonly reported infesting mammals that are feral (free-roaming cats and dogs) or introduced (red foxes, black rats and brown rats), suggesting the breakdown of barriers between wildlife and invasive reservoir species will increase spillover at the domestic animal - wildlife interface. Our empirical evidence shows that cat fleas are incredibly host-generalist, likely exhibiting a host range that is among the broadest of all ectoparasites. Reducing wild species' contact rates with domestic animals across natural and anthropogenic habitats, together with mitigating impacts of invasive reservoir hosts, will be crucial for reducing invasive flea infestations in wild mammals.

Stochastic process corrosion growth models for pipeline reliability

International Nuclear Information System (INIS)

Bazán, Felipe Alexander Vargas; Beck, André Teófilo

2013-01-01

Highlights: •Novel non-linear stochastic process corrosion growth model is proposed. •Corrosion rate modeled as random Poisson pulses. •Time to corrosion initiation and inherent time-variability properly represented. •Continuous corrosion growth histories obtained. •Model is shown to precisely fit actual corrosion data at two time points. -- Abstract: Linear random variable corrosion models are extensively employed in reliability analysis of pipelines. However, linear models grossly neglect well-known characteristics of the corrosion process. Herein, a non-linear model is proposed, where corrosion rate is represented as a Poisson square wave process. The resulting model represents inherent time-variability of corrosion growth, produces continuous growth and leads to mean growth at less-than-one power of time. Different corrosion models are adjusted to the same set of actual corrosion data for two inspections. The proposed non-linear random process corrosion growth model leads to the best fit to the data, while better representing problem physics

Coping with the gypsy moth on new frontiers of infestation

Science.gov (United States)

David A. Gansner; Owen W. Herrick; Garland N. Mason; Kurt W. Gottschalk

1987-01-01

Forest managers on new frontiers of infestation are searching for better ways to cope with the gypsy moth (Lymantria dispar). Presented herea are information and guidelines for remedial action to minimize future losses. Methods for assessing potential stand defoliation (susceptibility) and mortality (vulnerability), monitoring insect populations, and...

Occurrence of proscopiidae in Eucalyptus spp.: analysis of the infestations and spatial distribution

Directory of Open Access Journals (Sweden)

Alexandre dos Santos

2014-12-01

Full Text Available The objective of this research was to report the occurrence of proscopiidae and to quantify its infestation and spatial distribution in one experimental plantation of eucalypt clones. The study was conducted in an experimental field with eucalypt hybrids of Eucalyptus urophylla x Eucalyptus grandis (clones GG100, Eucalyptus urophylla x Eucalyptus grandis (H13 and of Eucalyptus urophylla x Eucalyptus camaldulensis (VM01. The plantation was established in three continuous blocks with 512 plants with 3 m x 2 m, in Cáceres municipality, Mato Grosso State, Brazil. Infestation of proscopiidae insects was detected two months after planting . The insects were collected for identification. The attacked trees were geo-referenced and the injuries were quantified. The spatial pattern of proscopiidae he attack was determinated using the location information of the damaged plants, which have been submitted to a quadrats analyses using Morisita and binomial dispersion indexes. All the collected insects have been identified as Tetanorhynchus smithi Rehn, 1904 (Orthoptera, Proscopiidae. The infestation differed significantly among the three eucalypts clones and aggregated spatial pattern of attack was observed. This is the first report of this species of proscopiidae in eucalyptus in Mato Grosso State.

Weed communities of rain-fed lowland rice vary with infestation by Rhamphicarpa fistulosa

Science.gov (United States)

Houngbédji, Tossimidé; Dessaint, Fabrice; Nicolardot, Bernard; Shykoff, Jacqui A.; Gibot-Leclerc, Stéphanie

2016-11-01

The facultative hemiparasitic plant Rhamphicarpa fistulosa (Orobanchaceae) thrives in seasonally wet soils in sub-Saharan Africa, mainly in marginal lowland rice growing environments where weeds are already a major constraint for rice production. Because lowland rice production is increasing in tropical Africa, it is important to ascertain the influence of R. fistulosa on weed plant communities in these rice-growing habitats. We investigated weed plant community richness and composition at four different levels of R. fistulosa infestation across two years of surveys from lowland rice fields in northern Togo (West Africa). Despite a lack of significant differences in community richness among sites with different R. fistulosa infestation levels, there were significant differences in community composition, both when estimated from presence-absence data and from relative abundance data, after controlling statistically for geographic proximity among sites. Rhamphicarpa fistulosa infestation, therefore, may influence the competitive balance between rice and its weeds and shape weed community structure. However, experimental studies are required to elucidate the weed host range of R. fistulosa and the direct and indirect effects of this hemiparasite in rice fields in order to predict its net impact on rice and its weed species.

Nonconvex Model of Material Growth: Mathematical Theory

Science.gov (United States)

Ganghoffer, J. F.; Plotnikov, P. I.; Sokolowski, J.

2018-06-01

The model of volumetric material growth is introduced in the framework of finite elasticity. The new results obtained for the model are presented with complete proofs. The state variables include the deformations, temperature and the growth factor matrix function. The existence of global in time solutions for the quasistatic deformations boundary value problem coupled with the energy balance and the evolution of the growth factor is shown. The mathematical results can be applied to a wide class of growth models in mechanics and biology.

Prophylactic treatment of flea-infested dogs with an imidacloprid / flumethrin collar (Seresto®, Bayer) to preempt infection with Dipylidium caninum.

Science.gov (United States)

Fourie, Josephus J; Crafford, Dionne; Horak, Ivan G; Stanneck, Dorothee

2013-08-01

The objective of the study was to determine the sustained effectiveness of 10 % imidacloprid and 4.5 % flumethrin, incorporated in a slow-release matrix collar, in preventing Dipylidium caninum infection in dogs after repeated laboratory infestations with fleas infected with metacestodes of this tapeworm. Efficacy against infection with D. caninum was evaluated by infesting 16 dogs with cat fleas (Ctenocephalides felis) on study days 7, 14, 21, 28, 35 and 42, from batches suitably infected with D. caninum metacestodes. Prior to each post-treatment infestation the D. caninum infection rate for the fleas was determined by microscopically examining 100 fleas for D. caninum metacestodes. The D. caninum prevalence in the fleas used for infestations ranged from 23 % to 52 %. Medicated collars were fitted to 8 of the dogs on study day 0. The weight of the IVP collars varied between 35.48 g and 38.48 g (average 37.16 g), whilst animal weight varied between 12.20 kg and 17.98 kg (treated group, n = 8, average 14.79 kg). Seven days later infestation of each of the 16 dogs with 250 fleas commenced. Infestations continued at weekly intervals until Day 42 with efficacy against fleas evaluated 24 hours after each infestation. From Days 21 to 74, infection of the dogs with D. caninum was verified (daily examination of faeces and cages for the presence of expelled proglottids). Calculation of prophylactic effectiveness of the collars in preventing infection with D. caninum was based on the difference in geometric mean numbers of scoleces between groups at necropsy on Day 75. Effective prevention of infection with D. caninum was found to be 96.6 %. Efficacy of the collars against fleas was ≥ 99.9 % for the duration of the assessment period. Newly acquired infestations of fleas are rapidly eliminated by the insecticidal components of the medicated collars over a period of several months. In the event of fleas being infected with metacestodes, with D. caninum can be prevented in

Fatal Ichthyocotylurus erraticus infestation in Inca terns (Larosterna inca) in a zoological collection.

Science.gov (United States)

Pieters, Wouter; Hoyer, Mark; Verstappen, Frank; Wolters, Marno; Ijzer, Jooske; de Jong, Sara; Cremers, Herman; Kik, Marja

2014-06-01

In a breeding group of Inca terns (Larosterna inca), 14 birds died without antemortem signs of illness. Other than a poor body condition and a bloody cloaca, no symptoms were observed. Gross necropsy revealed severe segmental hemorrhagic enteritis with intralesional trematodes in most birds. Histopathologic examination revealed infiltration of lymphocytes, plasma cells, and granulocytes in the lamina propria of the duodenum and cross-sections of trematodes in the lumen. The parasites were identified as Ichthyocotylurus erraticus, a trematode of fish-eating birds. The cause of the infestation most likely was the feeding of unfrozen fresh fish. We describe the first case of a lethal I. erraticus infestation in Inca terns.

Mapping giant reed (Arundo donax) infestations along the Texas-Mexico portion of the Rio Grande using aerial photography

Science.gov (United States)

Giant reed is an invasive weed throughout the southern half of the United States with the densest stands growing along the coastal rivers of southern California and the Rio Grande in Texas. The objective of this study was to use aerial photography to map giant reed infestations and estimate infested...

Modeling Root Growth, Crop Growth and N Uptake of Winter Wheat Based on SWMS_2D: Model and Validation

Directory of Open Access Journals (Sweden)

Dejun Yang

Full Text Available ABSTRACT Simulations for root growth, crop growth, and N uptake in agro-hydrological models are of significant concern to researchers. SWMS_2D is one of the most widely used physical hydrologically related models. This model solves equations that govern soil-water movement by the finite element method, and has a public access source code. Incorporating key agricultural components into the SWMS_2D model is of practical importance, especially for modeling some critical cereal crops such as winter wheat. We added root growth, crop growth, and N uptake modules into SWMS_2D. The root growth model had two sub-models, one for root penetration and the other for root length distribution. The crop growth model used was adapted from EU-ROTATE_N, linked to the N uptake model. Soil-water limitation, nitrogen limitation, and temperature effects were all considered in dry-weight modeling. Field experiments for winter wheat in Bouwing, the Netherlands, in 1983-1984 were selected for validation. Good agreements were achieved between simulations and measurements, including soil water content at different depths, normalized root length distribution, dry weight and nitrogen uptake. This indicated that the proposed new modules used in the SWMS_2D model are robust and reliable. In the future, more rigorous validation should be carried out, ideally under 2D situations, and attention should be paid to improve some modules, including the module simulating soil N mineralization.

Clonorchis sinensis infestation promotes three-dimensional aggregation and invasion of cholangiocarcinoma cells.

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Jihee Won

Full Text Available Numerous experimental and epidemiological studies have demonstrated a correlation between Clonorchis sinensis (C. sinensis infestation and cholangiocarcinoma (CCA. However, the role of C. sinensis in the increased invasiveness and proliferation involved in the malignancy of CCA has not been addressed yet. Here, we investigated the possibility that C. sinensis infestation promotes expression of focal and cell-cell adhesion proteins in CCA cells and secretion of matrix metalloproteinases (MMPs. Adhesion proteins help maintain cell aggregates, and MMPs promote the three-dimensional invasion of cells into the neighboring extracellular matrix (ECM. Using a novel microfluidic assay, we quantitatively addressed the role of excretory-secretory products (ESPs gradients from C. sinensis in promoting the invasion of cells into the neighboring ECM.

Testing R&D-Based Endogenous Growth Models

DEFF Research Database (Denmark)

Kruse-Andersen, Peter Kjær

2017-01-01

R&D-based growth models are tested using US data for the period 1953-2014. A general growth model is developed which nests the model varieties of interest. The model implies a cointegrating relationship between multifactor productivity, research intensity, and employment. This relationship...... is estimated using cointegrated VAR models. The results provide evidence against the widely used fully endogenous variety and in favor of the semi-endogenous variety. Forecasts based on the empirical estimates suggest that the slowdown in US productivity growth will continue. Particularly, the annual long...

Influence of Hemlock Woolly Adelgid Infestation Levels on Water Stress in Eastern Hemlocks within the Great Smoky Mountains National Park, U.S.A.

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Carla Coots

2015-01-01

Full Text Available Extensive mortality of eastern hemlock, Tsuga canadensis (L. Carrière, resulting from infestation by hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae, has occurred throughout the eastern United States. Although imidacloprid treatment can reduce tree mortality, its effectiveness can be influenced by several factors including tree water stress. The relationship between water stress and infestation rates is unknown, and an understanding of these could greatly increase the efficiency of management for this invasive insect. The primary objective of this study was to assess water stress at three levels of hemlock woolly adelgid infestations. Water stress was measured monthly for 13 months in eastern hemlocks classified as <25%, 25%–75%, and >75% infested. The highest level of water stress was found in those trees with hemlock woolly adelgid infestation levels greater than 75%. The lowest level of water stress was found in those trees with less than 25% hemlock woolly adelgid infestation levels. Knowledge of these effects can contribute to development of more effective chemical management strategies.

Needle terpenoid composition of Pinus halepensis (Mill.) Trees infested by the scale insect Marchalina hellenica (Genn.) in Greece

Science.gov (United States)

Athanassios Gallis; Carlos Arrabal; Aristotle C. Papageorgiou; Maria C. Garcia-Vallejo

2012-01-01

Needle terpenoid composition was determined by using GLC-MS in Pinus halepensis (Mill.) trees that were infested and not infested by the scale insect Marchalina hellenica. The study area was within the Forest National Park of the Cape Sounion, southern Attica region, Greece. A total of 43 compounds, 32 of which were identified...

Living with a crab: effect of Austinotheres angelicus (Brachyura, Pinnotheridae infestation on the condition of Saccostrea palmula (Ostreoida, Ostreidae

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Sebastián Mena

Full Text Available Some members of the Pinnotheridae family exhibit close symbiotic relationships with bivalves, which may cause severe damage to the mollusk. The condition index (CI is a tool that serves to evaluate the effect of biotic and abiotic factors on the morphology and physiology of mollusks, including those caused by symbiotic organisms. In the present study, we evaluated the effects of the infestation of the pinnotherid crab Austinotheres angelicus on the oyster Saccostrea palmula through monthly sampling (April to November 2012 in Punta Morales, Pacific coast of Costa Rica. A total of 245 oysters were analyzed, of which 38% were infested by the pinnotherid crab. Most of the oysters analyzed (92% varied in depth between 1.5 and 15.0 mm; 89% of the infested oysters were in this depth range. The prevalence was positively correlated with the depth of the oyster. Our results revealed that crab infestation could reduce the CI by 11 to 33%. The obtained findings suggest that the infestation by A. angelicus provokes alterations of the flesh production of the oyster, especially when the association is with a pair of crabs including an ovigerous female. The association of A. angelicus with S. palmula is best described as facultative parasitism for male crabs and obligatory parasitism for females.

The effect of salinity on the growth, sporulation and infection of Phytophthora ramorum

Science.gov (United States)

Phytophthora ramorum, a threat to Eastern U.S. forests, has been found in waterways outside the boundaries of infested ornamental nurseries. Very little is known about what factors are conducive to its survival and sporulation in water. This study examined the effect of salt on growth, sporulation,...

Kinetic Model of Growth of Arthropoda Populations

Science.gov (United States)

Ershov, Yu. A.; Kuznetsov, M. A.

2018-05-01

Kinetic equations were derived for calculating the growth of crustacean populations ( Crustacea) based on the biological growth model suggested earlier using shrimp ( Caridea) populations as an example. The development cycle of successive stages for populations can be represented in the form of quasi-chemical equations. The kinetic equations that describe the development cycle of crustaceans allow quantitative prediction of the development of populations depending on conditions. In contrast to extrapolation-simulation models, in the developed kinetic model of biological growth the kinetic parameters are the experimental characteristics of population growth. Verification and parametric identification of the developed model on the basis of the experimental data showed agreement with experiment within the error of the measurement technique.

Prevalence of head lice infestation and pediculicidal effect of permethrine shampoo in primary school girls in a low-income area in southeast of Iran.

Science.gov (United States)

Soleimani-Ahmadi, Moussa; Jaberhashemi, Seyed Aghil; Zare, Mehdi; Sanei-Dehkordi, Alireza

2017-07-24

Head lice infestation is a common public health problem that is most prevalent in primary school children throughout the world, especially in developing countries including different parts of Iran. This study aimed to determine the prevalence and risk factors associated with head lice infestation and pediculicidal effect of 1% permethrin shampoo in primary schools girls of Bashagard County, one of the low socioeconomic areas in southeast of Iran. In this interventional study six villages with similar demographical situations were selected and randomly assigned into intervention and control areas. In each area 150 girl students aged 7-12 years were selected randomly and screened for head lice infestation by visual scalp examination. In intervention area, treatment efficacy of 1% permethrin shampoo was evaluated via re-examination for infestation after one, two, and three weeks. Pre-tested structured questionnaire was used to collect data on socio-demographic and associated factors of head lice infestation. The prevalence of head lice infestation was 67.3%. There was significant association between head lice infestation and school grade, family size, parents' literacy, bathing facilities, frequency of hair washing, and use of shared articles (p shampoo for head lice treatment was 29.2, 68.9, and 90.3% after the first, second, and third weeks, respectively. The head lice infestation is a health problem in primary school girls of Bashagard County. Improvement of socioeconomic status and providing appropriate educational programs about head lice risk factors and prevention can be effective for reduction of infestation in this area. This trial has been registered and approved by Hormozgan University of Medical Sciences ethical committee (Trial No.764). Trial registration date: March 17 2014.

Ectoparasitic copepod infestation on a wild population of Neotropical catfish Sciades herzbergii Bloch, 1794: Histological evidences of lesions on host.

Science.gov (United States)

Fogel, Deborah; Fuentes, José Luis; Soto, Luz Marina; Lafuente, Wilson; Moncayo-Estrada, Rodrigo; López, Carlos

2017-12-01

We analyzed the infestation of the attached copepod species Lepeophtheirus sp on a wild population of Sciades herzbergii . The infestation and occurrence of attached copepods were related to body size, maturity and sex of host and the presence of lesions on fish skin were described. In 61 fish specimens (37 males and 24 females), total of 218 ectoparasitic copepods, including 204 mature and 14 immature stages were found. Copepods were attached to different regions of fish body without any regular pattern. The prevalence of infestation was 80.3% and intensity between 1 and 15 copepods/fish. No significant differences were found between sex or maturity and the presence of attached Lepeophtheirus sp. However, a contingency table including both sex and maturity status, and the total number of attached copepod per combined category showed a significant association. A positive correlation was found between body length of fish and intensity of infestation. Similarly, when comparing the infested fish according to group size, we found more copepods on larger individual. Attached copepods were associated with the presence of lesions visible to the naked eye. Histological analyses showed changes in cell architecture when sections of copepod-free tissues and attached copepods were compared.

Effects of insecticide spray application on insect pest infestation and ...

African Journals Online (AJOL)

Field studies were conducted during the 2008 - 2009 cropping season to determine the minimal insecticide application which can reduce cowpea yield losses on the field due to insect pest infestations in the Transkei region of South Africa. Treatments consisted of five cowpea varieties and four regimes of insecticide spray ...

Effect of abiotic factors on the infestation of spotted bollworm in advance genotypes of cotton

International Nuclear Information System (INIS)

Khaliq, A.; Subhani, M.N.; Murtaza, M.A.

2007-01-01

Studies were conducted on ten advance varieties of cotton Viz., BH-121, NIAB KRISHMA, DNA-137, VH-142, BH-125, MNH-635, SLH-627, FNH-245, CRIS-467 and CRIS-82 to see the effect of different weather conditions on the incidence and development of spotted bollworm infestation at Nuclear Institute for Agriculture and Biology (NIAB), Faisalabad. Temperature and relative humidity were correlated positively and rainfall affected negatively to the infestation of spotted bollworm on squares and green bolls in advance genotype of cotton. (author)

Differential model of macroeconomic growth with endogenic cyclicity

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Mikhail I. Geraskin

2017-09-01

Full Text Available Objective to elaborate a mathematical model of economic growth taking into account the cyclical nature of macroeconomic dynamics with the model parameters based on the Russian economy statistics. Methods economic and mathematical modeling system analysis regression factor analysis econometric time series analysis. Results the article states that under unstable economic growth in Russia forecasting of strategic prospects of the Russian economy is one of the topical directions of scientific studies. Furthermore construction of predictive models should be based on multiple factors taking into account such basic concepts as the neoKeynesian HarrodDomar model Ramsey ndash Cass ndash Koopmans model S. V. Dubovskiyrsquos concept as well as the neoclassical growth model by R. Solow. They served as the basis for developing a multifactor differential economic growth model which is a modification of the neoclassical growth model by R. Solow taking into account the laborsaving and capitalsaving forms of scientifictechnical progress and the Keynesian concept of investment. The model parameters are determined based on the dynamics of actual GDP employment fixed assets and investments in fixed assets for 19652016 in Russia on the basis of official statistics. The generalized model showed the presence of longwave fluctuations that are not detected during the individual periods modeling. The cyclical nature of macroeconomic dynamics with a period of 54 years was found which corresponds to the parameters of long waves by N. D. Kondratiev. Basing on the model the macroeconomic growth forecast was generated which shows that after 2020 the increase of scientifictechnical progress will be negative. Scientific novelty a model is proposed of the scientifictechnical progress indicator showing the growth rate of the capital productivity ratio to the saving rate a differential model of macroeconomic growth is obtained which endogenously takes cyclicity into account

Infestation of grape Vitis vinifera by Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) in sub-medium Sao Francisco valley, Brazil

Energy Technology Data Exchange (ETDEWEB)

Habibe, Tuffi C.; Viana, Rodrigo E.; Damasceno, Itala Cruz; Malavasi, Aldo [Biofabrica Moscamed Brasil, Juazeiro, BA (Brazil). Distrito Industrial do Sao Francisco; Nascimento, Antonio S., E-mail: antnasc@cnpmf.embrapa.b [EMBRAPA Mandioca e Fruticultura Tropical, Cruz das Almas, BA (Brazil); Paranhos, Beatriz A.J.; Haji, Francisca Nemaura P., E-mail: bjodao@cpatsa.embrapa.b [EMBRAPA Semi-Arido, Petrolina, PE (Brazil); Carvalho, Raimundo S. [Agencia de Defesa Agropecuaria da Bahia (ADAB), Salvador, BA (Brazil)

2006-07-01

The objective of this study was to assess the infestation level in grapes, Vitis vinifera, by the medfly,Ceratitis capitata in the Sao Francisco River Valley. The adult population was monitored with Jackson trap baited with trimedlure. Samples of grapes for larval infestation assessment were taken along three months, with a total of 116 kg. The average FTD (flies/trap/day) for medfly males was 0.26. The number of pupae obtained from the fruit samples was 471; 287 adults emerged (60.4%), all Ceratitis capitata. The infestation level was 4.0 pupa/kg of fresh fruit. We conclude that grape is a medfly host in SFV, occasionally causing high damage to production. (author)

Infestation of grape Vitis vinifera by Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) in sub-medium Sao Francisco valley, Brazil

International Nuclear Information System (INIS)

Habibe, Tuffi C.; Viana, Rodrigo E.; Damasceno, Itala Cruz; Malavasi, Aldo; Paranhos, Beatriz A.J.; Haji, Francisca Nemaura P.; Carvalho, Raimundo S.

2006-01-01

The objective of this study was to assess the infestation level in grapes, Vitis vinifera, by the medfly,Ceratitis capitata in the Sao Francisco River Valley. The adult population was monitored with Jackson trap baited with trimedlure. Samples of grapes for larval infestation assessment were taken along three months, with a total of 116 kg. The average FTD (flies/trap/day) for medfly males was 0.26. The number of pupae obtained from the fruit samples was 471; 287 adults emerged (60.4%), all Ceratitis capitata. The infestation level was 4.0 pupa/kg of fresh fruit. We conclude that grape is a medfly host in SFV, occasionally causing high damage to production. (author)

Infestation of mammals by Ixodes ricinus ticks (Acari: Ixodidae) in south-central Sweden.

Science.gov (United States)

Tälleklint, L; Jaenson, T G

1997-12-01

Infestation by Ixodes ricinus ticks on rodents, hares and cervids was examined at Bogesund, 10 km north of Stockholm, in south-central Sweden during 1991-1994 and on varying hares (Lepus timidus) at Stora Karlsö and Gotska Sandön in the Baltic Sea during 1992-1993. At Bogesund, there were great differences between two consecutive years in the number of I. ricinus larvae infesting bank voles (Clethrionomys glareolus). The seasonal pattern of infestation by I. ricinus larvae and nymphs on bank voles was unimodal in 1991, with peaks in June-July and bimodal in 1992, with peaks in June and August. Male bank voles, compared to females and older voles, compared to young voles, harboured greater numbers of I. ricinus ticks. Apodemus mice, compared to bank voles, harboured greater numbers of I. ricinus ticks. Ixodes ricinus larvae engorged on Apodemus mice were heavier than larvae engorged on bank voles and resulted in larger nymphs. However, there was no difference in the proportions of viable nymphs resulting from larvae engorged on mice or voles. The ranges in the numbers of I. ricinus ticks infesting individual hosts were 1-451 for rodents, 16-2374 for hares and 428-2072 for roe deer (Capreolus capreolus). These ranges of tick numbers are estimated to represent potential blood losses from individual hosts of approximately 0.2-65% for rodents, 0.2-13% for hares and 0.3-9.0% for roe deer. Within the populations of all host species examined, the distributions of all stages of I. ricinus were clumped, with most host individuals harbouring few ticks and only a few individuals harbouring many ticks. The data suggest that, even though a small proportion of tick hosts may be severely affected, the direct effects of feeding by I. ricinus are unlikely to play an important role on mammal population dynamics.

Prophylactic treatment of flea-infested cats with an imidacloprid/flumethrin collar to forestall infection with Dipylidium caninum.

Science.gov (United States)

Fourie, Josephus J; Crafford, Dionne; Horak, Ivan G; Stanneck, Dorothee

2012-07-27

The objective of the study was to determine the sustained effectiveness of 10% imidacloprid (w/w) and 4.5% flumethrin (w/w) incorporated in a slow-release matrix collar in preventing Dipylidium caninum infection in cats following repeated laboratory-infestations with fleas infected with metacestodes. Efficacy against infection with D. caninum was evaluated by infesting 16 cats with the flea Ctenocephalides felis felis infected with metacestodes of the tapeworm. Medicated collars were fitted to 8 of the cats and infestation of each cat with 200 fleas from a suitably infected batch commenced 7 days later and continued at weekly intervals until Day 28. Efficacy against fleas was evaluated 24 h after each infestation. Infection of the cats with D. caninum was verified by daily examination of the cats' faeces and immediate surroundings for proglottids from Day 21 to Day 60. Calculation of the prophylactic effectiveness of the collars in preventing infection of the cats with D. caninum was based on the difference in the geometric mean number of scoleces recovered from the gastrointestinal tracts of collared compared to untreated cats at necropsy on Day 61. Efficacy of the collars against infestation of the cats with fleas was 99.9% on Day 7 and 100% at each subsequent weekly assessment. Infection of the fleas with metacestodes was ≥40% in 7 to 13 day old fleas, but progressively decreased thereafter. At necropsy all the control cats were infected with D. caninum and harboured between 19 and 346 scoleces with a geometric mean of 58.3. A single treated cat was infected and harboured 2 scoleces. Effective prevention of infection with D. caninum, based on a comparison of the geometric mean numbers of scoleces recovered from control and treated cats, was 99.7%. The insecticidal components of the medicated collars are capable of rapidly eliminating newly-acquired infestations of fleas that are infected with the metacestodes of D. caninum, thus preventing infection with the

Prophylactic treatment of flea-infested cats with an imidacloprid/flumethrin collar to forestall infection with Dipylidium caninum

Directory of Open Access Journals (Sweden)

Fourie Josephus J

2012-07-01

Full Text Available Abstract Background The objective of the study was to determine the sustained effectiveness of 10% imidacloprid (w/w and 4.5% flumethrin (w/w incorporated in a slow-release matrix collar in preventing Dipylidium caninum infection in cats following repeated laboratory-infestations with fleas infected with metacestodes. Methods Efficacy against infection with D. caninum was evaluated by infesting 16 cats with the flea Ctenocephalides felis felis infected with metacestodes of the tapeworm. Medicated collars were fitted to 8 of the cats and infestation of each cat with 200 fleas from a suitably infected batch commenced 7 days later and continued at weekly intervals until Day 28. Efficacy against fleas was evaluated 24 h after each infestation. Infection of the cats with D. caninum was verified by daily examination of the cats’ faeces and immediate surroundings for proglottids from Day 21 to Day 60. Calculation of the prophylactic effectiveness of the collars in preventing infection of the cats with D. caninum was based on the difference in the geometric mean number of scoleces recovered from the gastrointestinal tracts of collared compared to untreated cats at necropsy on Day 61. Results Efficacy of the collars against infestation of the cats with fleas was 99.9% on Day 7 and 100% at each subsequent weekly assessment. Infection of the fleas with metacestodes was ≥40% in 7 to 13 day old fleas, but progressively decreased thereafter. At necropsy all the control cats were infected with D. caninum and harboured between 19 and 346 scoleces with a geometric mean of 58.3. A single treated cat was infected and harboured 2 scoleces. Effective prevention of infection with D. caninum, based on a comparison of the geometric mean numbers of scoleces recovered from control and treated cats, was 99.7%. Conclusion The insecticidal components of the medicated collars are capable of rapidly eliminating newly-acquired infestations of fleas that are infected

Pilot program (proof of concept) to mitigate Phytophthora ramorum at an infested nursery based on a systems approach

Science.gov (United States)

Gary Chastagner; Marianne Elliott

2017-01-01

The primary purpose of this program was to demonstrate proof of concept of certain mitigation approaches at a repeat P. ramorum-positive nursery site in Washington. Approaches included steam treatment of infested soil areas; creating a gravel “sandwich” above steam-treated and potentially infested soil surfaces; improving drainage systems; required...

Trace gas emissions from a chronosequence of bark beetle-infested lodgepole pine (Pinus contorta) forest stands

Science.gov (United States)

Norton, U.; Pendall, E.; Ewers, B. E.; Borkhuu, B.

2011-12-01

Severe outbreak of mountain pine beetle (MPB) and associated blue stain fungi have killed millions of hectares of coniferous forests in Western North America. This unprecedented disturbance has critically impacted ecosystem biogeochemistry and net carbon (C) and nitrogen (N) fluxes. However, the effects on greenhouse gas (GHG) emissions and drivers of biogeochemical processes that trigger GHG emissions following MPB infestations are not well understood. Such information can help assess regional-level changes in ecosystem C and N budgets and large-scale disturbance impacts on gas exchange between the atmosphere and terrestrial ecosystem. The overall objective of this research was to assess the immediate responses of GHG fluxes and soil C and N mineralization rates along a chronosequence of recently infested (1-yr, 3-yr and 4-yr ago) and uninfested (150-yr, 20-yr and 15-yr old) lodgepole pine stands in Medicine Bow National Forest in southeastern Wyoming. We hypothesize that MPB-induced tree mortality significantly changes stand-level hydrology, soil organic matter quality and chemistry of aboveground and belowground plant inputs. Consequently, these modifications influence nitrous oxide (N2O) emissions and methane (CH4) assimilation. Biweekly GHG measurements using static chambers were carried out during three consecutive snow-free growing seasons. Our results suggest that a stand infested within a year already shows a 20% increase in spring N2O production and a small decline in summer CH4 assimilation when compared to uninfested stands. Stands infested three and four years prior to our measurements produce over three times more N2O and assimilate three to five times less CH4 when compared to uninfested stands. In addition, a notable increase in soil moisture content and soil mineral N concentrations following early onset of the MPB infestation was also observed. An overall increase in N2O production and decline in CH4 assimilation following MPB infestation may

Tenancy, Marriage, and the Boll Weevil Infestation, 1892-1930.

Science.gov (United States)

Bloome, Deirdre; Feigenbaum, James; Muller, Christopher

2017-06-01

In the early twentieth century, the cotton-growing regions of the U.S. South were dominated by families of tenant farmers. Tenant farming created opportunities and incentives for prospective tenants to marry at young ages. These opportunities and incentives especially affected African Americans, who had few alternatives to working as tenants. Using complete-count Census of Population data from 1900-1930 and Census of Agriculture data from 1889-1929, we find that increases in tenancy over time increased the prevalence of marriage among young African Americans. We then study how marriage was affected by one of the most notorious disruptions to southern agriculture at the turn of the century: the boll weevil infestation of 1892-1922. Using historical Department of Agriculture maps, we show that the boll weevil's arrival reduced the share of farms worked by tenants as well as the share of African Americans who married at young ages. When the boll weevil infestation altered African Americans' opportunities and incentives to marry, the share of African Americans who married young fell accordingly. Our results provide new evidence about the effect of economic and political institutions on demographic transformations.

Les infestations par les poux de tête : une mise à jour clinique.

Science.gov (United States)

Cummings, Carl; Finlay, Jane C; MacDonald, Noni E

2018-02-01

Les infestations par les poux de tête ( Pediculus humanus capitis ) ne constituent ni un risque sanitaire primaire ni un vecteur de maladie, mais représentent plutôt un problème de société au coût impor- tant. Pour diagnostiquer une infestation, il faut déceler un pou vivant. Même si les pyréthines et la perméthrine demeurent les traitements de première intention au Canada, la solution de myristate d'isopropyle et de ST-cyclométhicone et la diméticone peuvent être envisagées en deuxième intention après un échec thérapeutique démontré.

Testing linear growth rate formulas of non-scale endogenous growth models

NARCIS (Netherlands)

Ziesemer, Thomas

2017-01-01

Endogenous growth theory has produced formulas for steady-state growth rates of income per capita which are linear in the growth rate of the population. Depending on the details of the models, slopes and intercepts are positive, zero or negative. Empirical tests have taken over the assumption of

Effect of Tylenchorhynchus robustoides on Growth of Buffalo Grass and Western Wheatgrass

OpenAIRE

Smolik, J. D.

1982-01-01

Tylenchorhynchus robustoides reduced (P = 0.05) growth of Agropyron smithii (western wheatgrass) at soil temperatures of 20, 25, 30, and 35 C. Growth reduction increased with increasing soil temperatures. Highest populations of T. robustoides were recovered at 25 and 30 C. Clipping weights of Buchloe dactyloides (buffalo grass) were reduced at 25 and 30 C; however, root/crown weights were reduced at 15, 20, 30, and 35 C in nematode infested vs. noninfested soil. Reproduction of T. robustoides...

Prevalence and risk factors of ticks infesting cattle reared on the ...

African Journals Online (AJOL)

risk factors among cattle reared on dairy, beef and free-range grazing farms of Haramaya University .... guidelines using gross and stereomicroscopic examination. .... with the risk and differences in the farm management systems, prevalence of ... tick genera combinations infested animals with diversified tick genera in Ha-.

Expression profiling of selected glutathione transferase genes in Zea mays (L.) seedlings infested with cereal aphids.

Science.gov (United States)

Sytykiewicz, Hubert; Chrzanowski, Grzegorz; Czerniewicz, Paweł; Sprawka, Iwona; Łukasik, Iwona; Goławska, Sylwia; Sempruch, Cezary

2014-01-01

The purpose of this report was to evaluate the expression patterns of selected glutathione transferase genes (gst1, gst18, gst23 and gst24) in the tissues of two maize (Zea mays L.) varieties (relatively resistant Ambrozja and susceptible Tasty Sweet) that were colonized with oligophagous bird cherry-oat aphid (Rhopalosiphum padi L.) or monophagous grain aphid (Sitobion avenae L.). Simultaneously, insect-triggered generation of superoxide anion radicals (O2•-) in infested Z. mays plants was monitored. Quantified parameters were measured at 1, 2, 4, 8, 24, 48 and 72 h post-initial aphid infestation (hpi) in relation to the non-infested control seedlings. Significant increases in gst transcript amounts were recorded in aphid-stressed plants in comparison to the control seedlings. Maximal enhancement in the expression of the gst genes in aphid-attacked maize plants was found at 8 hpi (gst23) or 24 hpi (gst1, gst18 and gst24) compared to the control. Investigated Z. mays cultivars formed excessive superoxide anion radicals in response to insect treatments, and the highest overproduction of O2•- was noted 4 or 8 h after infestation, depending on the aphid treatment and maize genotype. Importantly, the Ambrozja variety could be characterized as having more profound increments in the levels of gst transcript abundance and O2•- generation in comparison with the Tasty Sweet genotype.

Transcriptional signatures of parasitization and markers of colony decline in Varroa-infested honey bees (Apis mellifera).

Science.gov (United States)

Zanni, Virginia; Galbraith, David A; Annoscia, Desiderato; Grozinger, Christina M; Nazzi, Francesco

2017-08-01

Extensive annual losses of honey bee colonies (Apis mellifera L.) reported in the northern hemisphere represent a global problem for agriculture and biodiversity. The parasitic mite Varroa destructor, in association with deformed wing virus (DWV), plays a key role in this phenomenon, but the underlying mechanisms are still unclear. To elucidate these mechanisms, we analyzed the gene expression profile of uninfested and mite infested bees, under laboratory and field conditions, highlighting the effects of parasitization on the bee's transcriptome under a variety of conditions and scenarios. Parasitization was significantly correlated with higher viral loads. Honey bees exposed to mite infestation exhibited an altered expression of genes related to stress response, immunity, nervous system function, metabolism and behavioural maturation. Additionally, mite infested young bees showed a gene expression profile resembling that of forager bees. To identify potential molecular markers of colony decline, the expression of genes that were commonly regulated across the experiments were subsequently assessed in colonies experiencing increasing mite infestation levels. These studies suggest that PGRP-2, hymenoptaecin, a glucan recognition protein, UNC93 and a p450 cytocrome maybe suitable general biomarkers of Varroa-induced colony decline. Furthermore, the reliability of vitellogenin, a yolk protein previously identified as a good marker of colony survival, was confirmed here. Copyright © 2017 Elsevier Ltd. All rights reserved.

Graphene growth process modeling: a physical-statistical approach

Science.gov (United States)

Wu, Jian; Huang, Qiang

2014-09-01

As a zero-band semiconductor, graphene is an attractive material for a wide variety of applications such as optoelectronics. Among various techniques developed for graphene synthesis, chemical vapor deposition on copper foils shows high potential for producing few-layer and large-area graphene. Since fabrication of high-quality graphene sheets requires the understanding of growth mechanisms, and methods of characterization and control of grain size of graphene flakes, analytical modeling of graphene growth process is therefore essential for controlled fabrication. The graphene growth process starts with randomly nucleated islands that gradually develop into complex shapes, grow in size, and eventually connect together to cover the copper foil. To model this complex process, we develop a physical-statistical approach under the assumption of self-similarity during graphene growth. The growth kinetics is uncovered by separating island shapes from area growth rate. We propose to characterize the area growth velocity using a confined exponential model, which not only has clear physical explanation, but also fits the real data well. For the shape modeling, we develop a parametric shape model which can be well explained by the angular-dependent growth rate. This work can provide useful information for the control and optimization of graphene growth process on Cu foil.

Analysis of the Heterogeneity of Weed Infestation in Cereal Stands

Directory of Open Access Journals (Sweden)

Jan Winkler

2015-01-01

Full Text Available The aim of this study was to evaluate the heterogeneity of the incidence of individual weed species on a selected experimental field. This field was situated in the cadastre of the village Žabčice (South Moravian Region, Czech Republic. To evaluate the intensity of weed infestation, a field experiment was established. In 2011, altogether 33 weed species were identified in a stand of spring barley. In the next year, the total number of weeds in a stand of winter wheat was 22. Basing on results of the evaluation of infestation heterogeneity it was possible to detect the following trends: The first one concerned the incidence of significantly dominant species Chenopodium album and Veronica hederifolia in stands of spring barley and winter wheat, respectively. The second one expressed the incidence of the so-called sub-dominant species. Regarding the character of the incidence of these weed species it would be suitable to kill them by means of a targeted application of herbicides. Finally, the third trend concerned the incidence of that group of weeds that occurred in the major part of the experimental plot but in low numbers only. The abundance of these species was minimal and the total number of weed plants did not exceed the limit of 100 specimens. This group of weeds involved also those species that were markedly more frequent on plots situated closer to the margin of the experimental field. The targeted application of herbicides can be performed on plots with a lower level of weed infestation; another possibility, however, seems to be a targeted intervention that helps to control the incidence of a certain weed species and/or that is performed along the margin of the field where the different weed species are more frequent.

The impact of stubble crop on spring barley weed infestation

Directory of Open Access Journals (Sweden)

Eleonora Wrzesińska

2016-09-01

Full Text Available The condition and degree of weed infestation were determined in a spring barely crop grown in a short-term monoculture after mulching the soil with plants grown as a stubble crop (the control treatment without cover crop – lacy phacelia, white mustard, sunflower. The field experiment was carried out in 2010–2013 on good rye soil complex using a split-block design in four replications. The obtained results (the mean from all years of the experiment showed that the stubble crop, especially sunflower, reduced the diversity of weed species without causing at the same time changes in weed species dominance. In all the control treatments of the experiment, Chenopodium album and Fallopia convolvulus were the dominant species. The degree of spring barley weed infestation depended on the species grown in the cover crop. White mustard and lacy phacelia slightly increased the number of weeds but their fresh matter significantly increased. However, the sunflower cover crop significantly increased the number of weeds without any substantial differentiation of their fresh mass.

Incidence of Infestation and Larval Success of Emerald Ash Borer (Agrilus planipennis) on White Fringetree (Chionanthus virginicus), Chinese Fringetree (Chionanthus retusus), and Devilwood (Osmanthus americanus).

Science.gov (United States)

Cipollini, Don; Rigsby, Chad M

2015-10-01

We compared the incidence of infestation by emerald ash borer (EAB) and lilac borer on white fringetree to that of its Asian congener, Chinese fringetree, Chionanthus retusus, and a North American relative, devilwood, Osmanthus americanus. We also conducted laboratory bioassays to determine the suitability of these hosts for EAB larvae. At Spring Grove Cemetery and Arboretum in Cincinnati, Ohio, 9 of 28 white fringetrees examined were infested by EAB. Most of the white fringetrees had lilac borer infestation, and most of the trees infested by EAB also had lilac borer infestation. None of the 11 Chinese fringetrees examined were infested by either EAB or lilac borer. Each of the five devilwood individuals examined was infested by lilac borer, but not EAB. At The Morton Arboretum in Lisle, Illinois, 7 of 16 white fringetrees examined were infested by EAB, while none of the seven Chinese fringetrees examined were infested by either insect. A 40-d bioassay confirmed that white fringetree was an acceptable host, producing fourth-instar larvae that were smaller than those produced on a highly susceptible cultivar of green ash, Fraxinus pennsylvanica. No larvae survived on Chinese fringetree, and neonates were largely incapable of feeding on it. Two larvae survived on devilwood, reaching the second instar and excavating extensive galleries. Future work should be aimed at biotic and abiotic factors influencing the susceptibility of white fringetree, as well as further examination of close relatives for their vulnerability to EAB. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Unilateral phthiriasis palpebrarum infestation in a child during occlusion therapy for amblyopia: Case report.

Science.gov (United States)

Biler, Elif Demirkilinc; Selver, Ozlem Barut; Palamar, Melis; Uner, Ahmet; Uretmen, Onder

2016-01-01

An 8-year-old mentally retarded boy is brought to the hospital because of itching and burning at his right eye for 10 days. He was on full time right eye occlusion therapy for left amblyopia. Slit lamp examination revealed nits and adult lice anchored to the eyelashes in his occluded eye. Eyelashes and all detected lice and nits were mechanically trimmed, and sent for parasitological examination, which confirmed the diagnosis. Upon familial evaluation for additional infestation, the father was also found to have genital phthiriasis pubis and received appropriate treatment. While phthiriasis palpebrarum in children may signify sexual abuse, a detailed investigation by a child psychiatrist was performed and revealed no sign of abuse. Since the infestation was at only on occluded eye, the most possible explanation for the transmission was evaluated as the misusage of the adhesive patch in our case. In conclusion, sexual abuse should be excluded in children with phthiriasis palpebrarum and parents of amblyopic children on occlusion therapy should be warned about the importance of the hygiene of the patching in order to avoid any kind of infection and infestation.

Does hair coat length affect flea infestation in naturally infested dogs?

Science.gov (United States)

Silva, Guilherme Araujo Collares da; Lins, Luciana Araujo; Irala, Márcio Josué Costa; Cárcamo, Marcial Corrêa; Ribeiro, Paulo Bretanha

2016-01-01

The Siphonaptera are parasitic insects of endothermic animals and Ctenocephalides felis and Pulex irritans are important parasites of dogs. This study evaluated the effect of hair coat length and time of year on the population size of C. felis and P. irritans in naturally infested dogs. Fleas were collected from 14 dogs on a monthly basis for a year (February 2015 to January 2016) at a rural property in Bagé, Rio Grande do Sul, Brazil. The dogs were divided into two groups based on hair coat length: short coat (coat length coat (coat length > 5.0 cm, n= 7). In total, 2057 fleas were collected, 1541 of which were C. felis (74.91%) and 516 were P. irritans (25.08%). The number of C. felis and P. irritans individuals was significantly affected by hair coat length and time of year. The variation in flea numbers over the study months was higher in long-coated than in short-coated dogs for the two flea species and flea numbers increased with increasing mean monthly temperatures. The results provide a better understanding of behavioral aspects of flea communities in dogs and may help develop control strategies targeting these parasites.

Ectoparasitic copepod infestation on a wild population of Neotropical catfish Sciades herzbergii Bloch, 1794: Histological evidences of lesions on host

Directory of Open Access Journals (Sweden)

Deborah Fogel

2017-12-01

Full Text Available We analyzed the infestation of the attached copepod species Lepeophtheirus sp on a wild population of Sciades herzbergii. The infestation and occurrence of attached copepods were related to body size, maturity and sex of host and the presence of lesions on fish skin were described. In 61 fish specimens (37 males and 24 females, total of 218 ectoparasitic copepods, including 204 mature and 14 immature stages were found. Copepods were attached to different regions of fish body without any regular pattern. The prevalence of infestation was 80.3% and intensity between 1 and 15 copepods/fish. No significant differences were found between sex or maturity and the presence of attached Lepeophtheirus sp. However, a contingency table including both sex and maturity status, and the total number of attached copepod per combined category showed a significant association. A positive correlation was found between body length of fish and intensity of infestation. Similarly, when comparing the infested fish according to group size, we found more copepods on larger individual. Attached copepods were associated with the presence of lesions visible to the naked eye. Histological analyses showed changes in cell architecture when sections of copepod-free tissues and attached copepods were compared. Keywords: Damages, Fish, Lepeophtheirus, lesions, Sea lice, Parasitism

Association between khat chewing and intestinal parasitic infestations: a community based, cross-sectional study done in Jimma Town, Southwest Ethiopia.

Science.gov (United States)

Mossie, Andualem; Kebedez, Seleshi; Gobena, Teshome

2013-07-01

Khat (Catha edulis Forsk), is the psychostimulant herb cultivated in East Africa. Khat chewing could have health damaging effect. The aim of the present study was to determine the association between khat chewing and intestinal parasitic infestation. A cross sectional study was conducted in Jimma Town in July 2010. Structured questionnaire was administered to 991 individuals selected by a systematic sampling method. Stool samples were collected for the diagnosis of intestinal parasitic infestation. Data analysis was done using SPSS Version 16.0 for Windows. Among 991 respondents, 638 (64.4%) were females, 502 (50.7%) were Oromos, 486 (49%) were Orthodox and 475 (47.9%) of them were in the age group of 18-24 years old. The current prevalence of khat chewing was found to be 52.7%. The prevalence of single to multiple parasitic infestations was 33.4%. Negative association (p = 0.000) was recorded between the habit of khat chewing and intestinal parasitosis. Non-chewers were more affected than chewers. Higher proportion of non chewers was infested with parasites than chewers, suggesting that khat chewing might have a protective role against parasitic infestation. Further investigation on the effect of khat extract in in vitro and in vivo is recommended to disclose detail mechanisms.

Infestation of a bird and two cats by larvae of Plodia interpunctella (Lepidoptera: Pyralidae).

Science.gov (United States)

Pinckney, R D; Kanton, K; Foster, C N; Steinberg, H; Pellitteri, P

2001-09-01

The larvae of Plodia interpunctella (Hübner), commonly known as the Indian meal moth, often cause enormous losses in stored food supplies. We present three clinical case reports of accidental infestation by P. interpunctella larvae in two domestic cats and one parakeet. A larva gained entry into the avian host and subsequently migrated to the brain. It was alive, covered with "silk-like" fibers and confirmed to be a fourth instar. Plodia interpunctella larvae were excised with forceps from the subcutaneous tissues of the ear and neck of two cats in a different household. Previous reports of infestation by P. interpunctella larvae in vertebrates are unknown.

Dose rate effects on survival of two insect species which commonly infest stored corn

International Nuclear Information System (INIS)

Adem, E.; Uribe, R.M.; Watters, F.L.

1979-01-01

A study of the dose rate effects on survival of two species of insects which commonly infest commercial maize in Mexico was undertaken using 60 Co γ radiation and 1.0 MeV electrons, to determine whether an optimum dose rate exists for the irradiation of grain infested with these insects. Experiments have shown that the effectiveness of γ and electron irradiation were not influenced by dose rates from 10 to 120 Gy/min for 60 Co and 35 to 300 Gy/min for electrons when the insects were irradiated at 2500 Gy. Survival curves for each species are presented for both types of radiation. (author)

Domestic Rhodnius ecuadoriensis (Hemiptera, Reduviidae) infestation in Northern Peru: a comparative trial of detection methods during a six-month follow-up.

Science.gov (United States)

Cuba Cuba, César Augusto; Vargas, Franklin; Roldan, Judith; Ampuero, Cynthia

2003-01-01

Two passive methods in the assessment of intradomiciliary infestation by Rhodnius ecuadoriensis were tested: (i) the Gomes Nu ez sensor box (GN), (ii) sheets of white typing paper and (iii) one active timed manual method. The study was carried out in the Alto Chicama River Valley, Province of Gran Chim , Department of La Libertad. The study design consisted of an initial searching of triatomines inside of the domestic environment by the manual capture active procedure (man/hour) covering all the studied houses. Then, matched pairs of GN boxes and paper sheets were simultaneously installed in the bedrooms of 207 households distributed in 19 localities. A comparative prospective trial of these passive detection devices were monitored at 2, 4 and, finally 6 months follow-up. Parasitological Trypanosoma rangeli and/or T. cruzi infections were investigated in two houses with high level of infestation by R. ecuadoriensis. 16.9% of the 207 households investigated by an initial active manual method were infested with R. ecuadoriensis. The proportion of infested houses fluctuated from 6.2 to 55.5% amongst the 19 localities investigated. T. rangeli natural infection was detected in R. ecuadoriensis specimens collected in two households. Parasite rates in the bugs ranged from 16.6 to 21.7% respectively. The most striking fact was an average rate of salivary gland infection ranging from 7.4 to 8.3%. At the end of the sixth month period, a cumulative incidence of 31.4% of positive GN boxes against 15.9% for paper sheets was recorded. All three methods combined detected domestic infestation in 129 (62.3%) of the 207 houses studied in the 19 localities. The range of houses infested varies from 6.7% to 92.9%. In areas with low bug density infestation rates, the methodology experienced in our studies, seems to be the best choice for investigations on domestic R. ecuadoriensis populations.

Growth curve models and statistical diagnostics

CERN Document Server

Pan, Jian-Xin

2002-01-01

Growth-curve models are generalized multivariate analysis-of-variance models. These models are especially useful for investigating growth problems on short times in economics, biology, medical research, and epidemiology. This book systematically introduces the theory of the GCM with particular emphasis on their multivariate statistical diagnostics, which are based mainly on recent developments made by the authors and their collaborators. The authors provide complete proofs of theorems as well as practical data sets and MATLAB code.

Armillifer armillatus infestation in Human; public health scenario of a ...

African Journals Online (AJOL)

We report cases of Armillifer Armillatus infestation in three Nigerian adults within two and half years in our health facility. The first patient was a 70 year old farmer and a regular consumer of snake meat for over 50 years. He presented in February, 2014 for follow-up visit as he was a known systemic hypertensive patient.

Mitochondrial genome sequencing reveals potential origins of the scabies mite Sarcoptes scabiei infesting two iconic Australian marsupials

OpenAIRE

Fraser, Tamieka A.; Shao, Renfu; Fountain-Jones, Nicholas M.; Charleston, Michael; Martin, Alynn; Whiteley, Pam; Holme, Roz; Carver, Scott; Polkinghorne, Adam

2017-01-01

Background Debilitating skin infestations caused by the mite, Sarcoptes scabiei, have a profound impact on human and animal health globally. In Australia, this impact is evident across different segments of Australian society, with a growing recognition that it can contribute to rapid declines of native Australian marsupials. Cross-host transmission has been suggested to play a significant role in the epidemiology and origin of mite infestations in different species but a chronic lack of gene...

Patterns of infestation by chigger mites in four diurnal lizard species from a Restinga habitat (Jurubatiba) of southeastern Brazil.

Science.gov (United States)

Cunha-Barros, M; Van Sluys, M; Vrcibradic, D; Galdino, C A; Hatano, F H; Rocha, C F

2003-08-01

We studied the parasitism by larvae of the chigger mite Eutrombicula alfreddugesi on the lizard community of Restinga de Jurubatiba, Rio de Janeiro State, Southeastern Brazil. We investigated the patterns of infestation (prevalence and intensity) of chigger mites in four sympatric lizards: Tropidurus torquatus, Mabuya agilis, M. macrorhyncha and Cnemidophorus littoralis. All lizards collected were checked for the presence of mites, which were counted under stereomicroscope. We tested the relationship between intensity of infestation and lizard body size for each species using regression analysis. The prevalences and mean intensities (+ one standard deviation) of infestation on each host species were, respectively: 100%; 86.4 + 94.6 in T. torquatus (n = 62); 100%; 20.9 + 9.3 in M. agilis (n = 7); 100%; 11.1 + 13.1 in M. macrorhyncha (n = 12); and 95.2%; 19.1 + 16.8 in C. littoralis (n = 21). Only for C. littoralis did body size significantly affect the intensity of infestation (r = 0.27, p = 0.02). For all lizard species, the body parts where chiggers occurred with the highest intensity were those of skin folds and joint regions.

Ticks infesting wild and domestic animals and humans of Sri Lanka with new host records.

Science.gov (United States)

Liyanaarachchi, D R; Rajakaruna, R S; Dikkumbura, A W; Rajapakse, R P V J

2015-02-01

An island-wide collection of tick species infesting humans, domesticated and wild animals and questing ticks in domestic and peridomestic environments was carried out during 2009-2011. A total of 30,461 ticks were collected from 30 different hosts and free living stages from the ground. The collection consisted of 22 tick species from 30 different hosts recording 12 tick species from humans, 19 from domesticated animals and 21 from wild animals, with a total of 97 new host records. The most common tick species on humans were Dermacentor auratus and Amblyomma testudinairum, while Haemaphysalis intermedia, Rhipicephalus microplus and Rhipicephalus sanguineus were common in domesticated and wild animals sharing 20 host species. Among the questing ticks, immature D. auratus was the most abundant. Humans and domesticated animals were mostly infested by the nymphal stages while adult ticks were found on wild animals. High number of new host records could be due to domestic animals picking tick species from wildlife and vise versa at the human/animal interface. Habitat destruction due to forest fragmentation has lead to wild animals roaming in urban and semi-urban neighbourhoods increasing the interactions of wild animals with domesticated animals. Wild animals play a significant role as a reservoir of many tick borne infections which can easily be spread to domesticated animals and then to humans via tick infestations. Data in this paper are useful for those interested in tick infesting wild and domestic animals and humans in describing the zoonotic potential of tick borne infections. Copyright © 2014 Elsevier B.V. All rights reserved.

Pest Prevalence and Evaluation of Community-Wide Integrated Pest Management for Reducing Cockroach Infestations and Indoor Insecticide Residues.

Science.gov (United States)

Zha, Chen; Wang, Changlu; Buckley, Brian; Yang, Ill; Wang, Desen; Eiden, Amanda L; Cooper, Richard

2018-04-02

Pest infestations in residential buildings are common, but community-wide pest survey data are lacking. Frequent insecticide applications for controlling indoor pests leave insecticide residues and pose potential health risks to residents. In this study, a community-wide pest survey was carried out in a housing complex consisting of 258 units in 40 buildings in New Brunswick, New Jersey. It was immediately followed by implementation of an integrated pest management (IPM) program in all the cockroach-infested apartments and two bed bug apartments with the goal of eliminating pest infestations, reducing pyrethroid residues, and increasing resident satisfaction with pest control services. The IPM-treated apartments were revisited and treated biweekly or monthly for 7 mo. Initial inspection found the top three pests and their infestation rates to be as follows: German cockroaches (Blattella germanica L. [Blattodea: Blattellidae]), 28%; rodents, 11%; and bed bugs (Cimex lectularius L. [Hemiptera: Cimicidae]), 8%. Floor wipe samples were collected in the kitchens and bedrooms of 20 apartments for pyrethroid residue analysis before the IPM implementation; 17 of the 20 apartments were resampled again at 7 mo. The IPM program reduced cockroach counts per apartment by 88% at 7 wk after initial treatment. At 7 mo, 85% of the cockroach infestations found in the initial survey were eliminated. The average number of pyrethroids detected decreased significantly from 6 ± 1 (mean ± SEM) and 5 ± 1 to 2 ± 1 and 3 ± 1 in the kitchens and bedrooms, respectively. The average concentrations of targeted pyrethroids residue also decreased significantly in the kitchens and bedrooms.

Investigations on the biology, epidemiology, pathology, and control of Tunga penetrans in Brazil: VII. The importance of animal reservoirs for human infestation.

Science.gov (United States)

Pilger, Daniel; Schwalfenberg, Stefan; Heukelbach, Jörg; Witt, Lars; Mehlhorn, Heinz; Mencke, Norbert; Khakban, Adak; Feldmeier, Hermann

2008-04-01

In Brazil tungiasis is endemic in many resource-poor communities, where various domestic and sylvatic animals act as reservoirs for this zoonosis. To determine the role of animal reservoirs in human tungiasis, a cross-sectional study was performed in a traditional fishing community in northeast Brazil. The human and the animal populations were examined for the presence of embedded sand fleas and the prevalence and the intensity of infestation were correlated. The overall prevalence of tungiasis in humans was 39% (95% CI 34-43%). Of six mammal species present in the village, only cats and dogs were found infested. The prevalence in these animals was 59% (95% CI 50-68%). In households, where infested pet animals were present, a higher percentage of household members had tungiasis (42% [95% CI 30-53%] versus 27% [20-33%], p=0.02), and the intensity of the infestation was higher (six lesions versus two lesions, p=0.01). The intensity of infestation in animals correlated with the intensity of infestation in humans (rho=0.3, p=0.02). Living in a household with an infested dog or cat led to a 1.6-fold (95% CI 1.1-2.3, p=0.015) increase in the odds for the presence of tungiasis in household members in the bivariate analysis and remained a significant risk factor in the multivariate regression analysis. The study shows that in this impoverished community tungiasis is highly prevalent in humans and domestic animals. In particular, it underlines the importance to include animals in control operation aiming at the reduction of disease occurrence in the human population.

Modelling asymmetric growth in crowded plant communities

DEFF Research Database (Denmark)

Damgaard, Christian

2010-01-01

A class of models that may be used to quantify the effect of size-asymmetric competition in crowded plant communities by estimating a community specific degree of size-asymmetric growth for each species in the community is suggested. The model consists of two parts: an individual size......-asymmetric growth part, where growth is assumed to be proportional to a power function of the size of the individual, and a term that reduces the relative growth rate as a decreasing function of the individual plant size and the competitive interactions from other plants in the neighbourhood....

Behavioral Modulation of Infestation by Varroa destructor in Bee Colonies. Implications for Colony Stability.

Science.gov (United States)

de Figueiró Santos, Joyce; Coelho, Flávio Codeço; Bliman, Pierre-Alexandre

2016-01-01

Colony Collapse Disorder (CCD) has become a global problem for beekeepers and for the crops that depend on bee pollination. While many factors are known to increase the risk of colony collapse, the ectoparasitic mite Varroa destructor is considered to be the most serious one. Although this mite is unlikely to cause the collapse of hives itself, it is the vector for many viral diseases which are among the likely causes for Colony Collapse Disorder. The effects of V. destructor infestation differ from one part of the world to another, with greater morbidity and higher colony losses in European honey bees (EHB) in Europe, Asia and North America. Although this mite has been present in Brazil for many years, there have been no reports of colony losses amongst Africanized Honey Bees (AHB). Studies carried out in Mexico have highlighted different behavioral responses by the AHB to the presence of the mite, notably as far as grooming and hygienic behavior are concerned. Could these explain why the AHB are less susceptible to Colony Collapse Disorder? In order to answer this question, we have developed a mathematical model of the infestation dynamics to analyze the role of resistance behavior by bees in the overall health of the colony, and as a consequence, its ability to face epidemiological challenges.

Behavioral Modulation of Infestation by Varroa destructor in Bee Colonies. Implications for Colony Stability.

Directory of Open Access Journals (Sweden)

Joyce de Figueiró Santos

Full Text Available Colony Collapse Disorder (CCD has become a global problem for beekeepers and for the crops that depend on bee pollination. While many factors are known to increase the risk of colony collapse, the ectoparasitic mite Varroa destructor is considered to be the most serious one. Although this mite is unlikely to cause the collapse of hives itself, it is the vector for many viral diseases which are among the likely causes for Colony Collapse Disorder. The effects of V. destructor infestation differ from one part of the world to another, with greater morbidity and higher colony losses in European honey bees (EHB in Europe, Asia and North America. Although this mite has been present in Brazil for many years, there have been no reports of colony losses amongst Africanized Honey Bees (AHB. Studies carried out in Mexico have highlighted different behavioral responses by the AHB to the presence of the mite, notably as far as grooming and hygienic behavior are concerned. Could these explain why the AHB are less susceptible to Colony Collapse Disorder? In order to answer this question, we have developed a mathematical model of the infestation dynamics to analyze the role of resistance behavior by bees in the overall health of the colony, and as a consequence, its ability to face epidemiological challenges.

Evaluation of the speed of kill, effects on reproduction, and effectiveness in a simulated infested-home environment of sarolaner (Simparica™) against fleas on dogs.

Science.gov (United States)

Six, Robert H; Becskei, Csilla; Carter, Lori; Gale, Boyd; Young, David R; Mahabir, Sean P; Chapin, Sara; Myers, Melanie R

2016-05-30

Four studies were conducted to evaluate the speed of kill, effect on egg production, and efficacy in a simulated infested-home environment of a novel isoxazoline, sarolaner (Simparica™, Zoetis), against fleas on dogs. Individually identified and housed, purpose-bred Beagles were used in each study and were allocated randomly to groups based on pretreatment parasite counts. In two speed of kill studies, groups of dogs infested with 100 fleas prior to treatment were treated orally with placebo or sarolaner tablets providing the minimum dose of 2mg/kg and then re-infested with fleas weekly for five weeks post-treatment. Comb counts were conducted to determine the numbers of viable fleas at one to three, four, eight and 12h after treatment and each subsequent infestation. In the egg production study, sarolaner- and placebo-treated dogs were similarly challenged with fleas and at 48h after each infestation the dogs were housed for 20h in cages allowing the collection and counting of all flea eggs produced during this period. Collected eggs were incubated to evaluate hatch and development to adults. The last study used dogs housed in a flea-infested simulated-home environment. Dogs were allocated to treatment with either placebo or sarolaner tablets providing a dose of 2mg/kg once a month for three treatments. Flea infestations were assessed by comb counts (fleas were replaced on the dogs) on Days 14, 30, 44, 60, 74 and 90. The speed of kill studies demonstrated that a single 2mg/kg oral dose of sarolaner started killing fleas within three to four hours after treatment or subsequent re-infestations for up to a month, and achieved ≥98% control of fleas by eight hours after treatment or re-infestation for 28 days. In the study to assess effects on flea reproduction, a single oral treatment of sarolaner resulted in the complete cessation of egg-laying for 35 days. This rapid kill of fleas and inhibition of reproduction were confirmed in a simulated-home environment

A new model for simulating growth in fish

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Johannes Hamre

2014-01-01

Full Text Available A real dynamic population model calculates change in population sizes independent of time. The Beverton & Holt (B&H model commonly used in fish assessment includes the von Bertalanffy growth function which has age or accumulated time as an independent variable. As a result the B&H model has to assume constant fish growth. However, growth in fish is highly variable depending on food availability and environmental conditions. We propose a new growth model where the length increment of fish living under constant conditions and unlimited food supply, decreases linearly with increasing fish length until it reaches zero at a maximal fish length. The model is independent of time and includes a term which accounts for the environmental variation. In the present study, the model was validated in zebrafish held at constant conditions. There was a good fit of the model to data on observed growth in Norwegian spring spawning herring, capelin from the Barents Sea, North Sea herring and in farmed coastal cod. Growth data from Walleye Pollock from the Eastern Bering Sea and blue whiting from the Norwegian Sea also fitted reasonably well to the model, whereas data from cod from the North Sea showed a good fit to the model only above a length of 70 cm. Cod from the Barents Sea did not grow according to the model. The last results can be explained by environmental factors and variable food availability in the time under study. The model implicates that the efficiency of energy conversion from food decreases as the individual animal approaches its maximal length and is postulated to represent a natural law of fish growth.

Treatment and control of Trixacarus caviae infestation in a conventional guinea pig (Cavia porcellus) breeding colony

OpenAIRE

Nath, Anjan Jyoti

2015-01-01

A case of sarcoptic mange caused by Trixacarus caviae in a conventional guinea pig breeding colony is reported. The infestation was reported in a large colony of guinea pigs during the month of July, 2013 affecting 30 breeder guinea pigs. Severely infested animals were treated individually with subcutaneous injection of ivermectin 1 % w/v (Neomec®) at the rate of 400 µg/kg body weight 10 days apart. Three doses of ivermectin were sufficient to eliminate the parasite which tested negative afte...

Modeling Population Growth and Extinction

Science.gov (United States)

Gordon, Sheldon P.

2009-01-01

The exponential growth model and the logistic model typically introduced in the mathematics curriculum presume that a population grows exclusively. In reality, species can also die out and more sophisticated models that take the possibility of extinction into account are needed. In this article, two extensions of the logistic model are considered,…

Modeling of Hybrid Growth Wastewater Bio-reactor

International Nuclear Information System (INIS)

EI Nashaei, S.; Garhyan, P.; Prasad, P.; Abdel Halim, H.S.; Ibrahim, G.

2004-01-01

The attached/suspended growth mixed reactors are considered one of the recently tried approaches to improve the performance of the biological treatment by increasing the volume of the accumulated biomass in terms of attached growth as well as suspended growth. Moreover, the domestic WW can be easily mixed with a high strength non-hazardous industrial wastewater and treated together in these bio-reactors if the need arises. Modeling of Hybrid hybrid growth wastewater reactor addresses the need of understanding the rational of such system in order to achieve better design and operation parameters. This paper aims at developing a heterogeneous mathematical model for hybrid growth system considering the effect of diffusion, external mass transfer, and power input to the system in a rational manner. The model will be based on distinguishing between liquid/solid phase (bio-film and bio-floc). This model would be a step ahead to the fine tuning the design of hybrid systems based on the experimental data of a pilot plant to be implemented in near future

Demodex spp. Infestation in a breast-cancer patient: A case report ...

African Journals Online (AJOL)

Immune system becomes suppressed in cancer patients who undergo chemotherapy, and as a result these patients become vulnerable to infestations. In our case, a 45 year-old female has been admitted to oncology clinic for a medical treatment of breast cancer. Her systematic physical examination was normal, except ...

A report on the alimentary canal helminthic infestation of stray and pet dogs in Tabriz

Directory of Open Access Journals (Sweden)

Y Gharedaghi

2008-08-01

Full Text Available From September to December 2007, fecal specimens of 100 stray and pet dogs in Tabriz were examined by saturated salt flotation and Telmann sedimentation methods to determine the prevalence of gastrointestinal helminth infestation. Helminth infestation was encountered in 31 (31% of the fecal samples examined. The eggs of two different cestodes and three different nematodes were identified in the contaminated fecal samples. The helminth eggs found were identified as Taenia hydatigena (4%, Dipylidium caninum (6%, Toxocara canis (10%, Ancylostoma caninum (6% and Trichuris vulpis (5%. No trematoda eggs and nematode larvae were found in this study.

Economic Growth Models Transition

Directory of Open Access Journals (Sweden)

Coralia Angelescu

2006-03-01

Full Text Available The transitional recession in countries of Eastern Europe has been much longer than expected. The legacy and recent policy mistakes have both contributed to the slow progress. As structural reforms and gradual institution building have taken hold, the post-socialist economics have started to recover, with some leading countries building momentum toward faster growth. There is a possibility that in wider context of globalization several of these emerging market economies will be able to catch up with the more advanced industrial economies in a matter of one or two generations. Over the past few years, most candidate countries have made progress in the transition to a competitive market economy, macroeconomic stabilization and structural reform. However their income levels have remained far below those in the Member States. Measured by per capita income in purchasing power standards, there has been a very limited amount of catching up over the past fourteen years. Prior, the distinctions between Solow-Swan model and endogenous growth model. The interdependence between transition and integration are stated in this study. Finally, some measures of macroeconomic policy for sustainable growth are proposed in correlation with real macroeconomic situation of the Romanian economy. Our study would be considered the real convergence for the Romanian economy and the recommendations for the adequate policies to achieve a fast real convergence and sustainable growth.

Economic Growth Models Transition

Directory of Open Access Journals (Sweden)

Coralia Angelescu

2006-01-01

Full Text Available The transitional recession in countries of Eastern Europe has been much longer than expected. The legacy and recent policy mistakes have both contributed to the slow progress. As structural reforms and gradual institution building have taken hold, the post-socialist economics have started to recover, with some leading countries building momentum toward faster growth. There is a possibility that in wider context of globalization several of these emerging market economies will be able to catch up with the more advanced industrial economies in a matter of one or two generations. Over the past few years, most candidate countries have made progress in the transition to a competitive market economy, macroeconomic stabilization and structural reform. However their income levels have remained far below those in the Member States. Measured by per capita income in purchasing power standards, there has been a very limited amount of catching up over the past fourteen years. Prior, the distinctions between Solow-Swan model and endogenous growth model. The interdependence between transition and integration are stated in this study. Finally, some measures of macroeconomic policy for sustainable growth are proposed in correlation with real macroeconomic situation of the Romanian economy. Our study would be considered the real convergence for the Romanian economy and the recommendations for the adequate policies to achieve a fast real convergence and sustainable growth.

Recent advances in modelling creep crack growth

International Nuclear Information System (INIS)

Riedel, H.

1988-08-01

At the time of the previous International Conference on Fracture, the C* integral had long been recognized as a promising load parameter for correlating crack growth rates in creep-ductile materials. The measured crack growth rates as a function of C* and of the temperature could be understood on the basis of micromechanical models. The distinction between C*-controlled and K I -controlled creep crack growth had been clarified and first attempts had been made to describe creep crack growth in the transient regime between elastic behavior and steady-state creep. This paper describes the progress in describing transient crack growth including the effect of primary creep. The effect of crack-tip geometry changes by blunting and by crack growth on the crack-tip fields and on the validity of C* is analyzed by idealizing the growing-crack geometry by a sharp notch and using recent solutions for the notch-tip fields. A few new three-dimensional calculations of C* are cited and important theoretical points are emphasized regarding the three-dimensional fields at crack tips. Finally, creep crack growth is described by continuum-damage models for which similarity solutions can be obtained. Crack growth under small-scale creep conditions turns out to be difficult to understand. Slightly different models yield very different crack growth rates. (orig.) With 4 figs

Expression Profiling of Selected Glutathione Transferase Genes in Zea mays (L.) Seedlings Infested with Cereal Aphids

Science.gov (United States)

Sytykiewicz, Hubert; Chrzanowski, Grzegorz; Czerniewicz, Paweł; Sprawka, Iwona; Łukasik, Iwona; Goławska, Sylwia; Sempruch, Cezary

2014-01-01

The purpose of this report was to evaluate the expression patterns of selected glutathione transferase genes (gst1, gst18, gst23 and gst24) in the tissues of two maize (Zea mays L.) varieties (relatively resistant Ambrozja and susceptible Tasty Sweet) that were colonized with oligophagous bird cherry-oat aphid (Rhopalosiphum padi L.) or monophagous grain aphid (Sitobion avenae L.). Simultaneously, insect-triggered generation of superoxide anion radicals (O2 •−) in infested Z. mays plants was monitored. Quantified parameters were measured at 1, 2, 4, 8, 24, 48 and 72 h post-initial aphid infestation (hpi) in relation to the non-infested control seedlings. Significant increases in gst transcript amounts were recorded in aphid-stressed plants in comparison to the control seedlings. Maximal enhancement in the expression of the gst genes in aphid-attacked maize plants was found at 8 hpi (gst23) or 24 hpi (gst1, gst18 and gst24) compared to the control. Investigated Z. mays cultivars formed excessive superoxide anion radicals in response to insect treatments, and the highest overproduction of O2 •− was noted 4 or 8 h after infestation, depending on the aphid treatment and maize genotype. Importantly, the Ambrozja variety could be characterized as having more profound increments in the levels of gst transcript abundance and O2 •− generation in comparison with the Tasty Sweet genotype. PMID:25365518

Parasites of domestic and wild animals in South Africa. L. Ixodid ticks infesting horses and donkeys.

Science.gov (United States)

Horak, Ivan G; Heyne, Heloise; Halajian, Ali; Booysen, Shalaine; Smit, Willem J

2017-02-28

The aim of the study was to determine the species spectrum of ixodid ticks that infest horses and donkeys in South Africa and to identify those species that act as vectors of disease to domestic livestock. Ticks were collected opportunistically from 391 horses countrywide by their owners or grooms, or by veterinary students and staff at the Faculty of Veterinary Science, University of Pretoria. Ticks were also collected from 76 donkeys in Limpopo Province, 2 in Gauteng Province and 1 in North West province. All the ticks were identified by means of a stereoscopic microscope. Horses were infested with 17 tick species, 72.1% with Rhipicephalus evertsi evertsi, 19.4% with Amblyomma hebraeum and 15.6% with Rhipicephalus decoloratus. Rhipicephalus evertsi evertsi was recovered from horses in all nine provinces of South Africa and R. decoloratus in eight provinces. Donkeys were infested with eight tick species, and 81.6% were infested with R. evertsi evertsi, 23.7% with A. hebraeum and 10.5% with R. decoloratus. Several tick species collected from the horses and donkeys are the vectors of economically important diseases of livestock. Rhipicephalus evertsi evertsi is the vector of Theileria equi, the causative organism of equine piroplasmosis. It also transmits Anaplasma marginale, the causative organism of anaplasmosis in cattle. Amblyomma hebraeum is the vector of Ehrlichia ruminantium, the causative organism of heartwater in cattle, sheep and goats, whereas R. decoloratus transmits Babesia bigemina, the causative organism of babesiosis in cattle.

Establishment of Black Ant (Dolichoderus thoracicuson Cocoa Plantation and Its Effects on Helopeltisspp. Infestation

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Soekadar Wiryadiputra

2007-05-01

Full Text Available Black ant (Dolichoderus thoracicusis the efficient biological control agent in suppressing main cocoa pests. It was reported that besides controlling the cocoa mirids, Helopeltisspp., this agent also can be used for biological control of cocoa pod borer (Conopomorpha cramerellaand rodents pest. Nevertheles, establishment of black ant in cocoa plantation is difficult. The objectives of research were to obtain the best method of black ant establisment and to know its effect on suppressing population and infestation of Helopeltis spp. The experiment was conducted on two cocoa ecosystems, namely cocoa plantation with coconut shading trees and with Gliricidia sepium shading trees. There were six methods of black ant establisment tried using a combination between black ant nest types and innoculation of mealybug (Cataenococcus hispidus. A control plot also added on these trial, therefore seven treatments were tried in this experiment and each treatmentwasreplicated three times. The results revealedthat on cocoa shaded by coconuts, ant establishment by the nests of coconut leaves combined with mealybug(Cataenococcus hispidusinoculation on husk wedges were the best method and could effectively control Helopeltis infestation. Good results of ant establishment also occurred on cocoa shaded by Gliricidia but its effect on Helopeltis infestation has not been significant. Four months after establishment of black ant on cocoa with coconut shading trees, Helopeltisspp. population on the plots treated by coconut leaves nest combined with innoculation of mealybug using husk wedges were very low, namely only one Helopeltisper 36 cocoa trees, whereas on control plot reaches of 85 Helopeltis. Infestation of Helopeltis measured by percentage of trees occupied by Helopeltisper 36 cocoa trees in the same period and treatment plot revealed also very low, namely 1.04% compared to 27.86% on that of the control plot. Key words : Cocoa, black ant (Dolichoderus thoracicus

Natural Field Infestation of Mangifera casturi and Mangifera lalijiwa by Oriental Fruit Fly, Bactrocera dorsalis (Diptera: Tephritidae)

Science.gov (United States)

McQuate, Grant T; Sylva, Charmaine D; Liquido, Nicanor J

2017-01-01

Mango, Mangifera indica (Anacardiaceae), is a crop cultivated pantropically. There are, however, many other Mangifera spp (“mango relatives”) which have much more restricted distributions and are poorly known but have potential to produce mango-like fruits in areas where mangoes do not grow well or could be tapped in mango breeding programs. Because of the restricted distribution of many of the Mangifera spp, there has also been limited data collected on susceptibility of their fruits to infestation by tephritid fruit flies which is important to know for concerns both for quality of production and for quarantine security of fruit exports. Here, we report on natural field infestation by the oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae), of two mango relatives native to Indonesia: Mangifera casturi and Mangifera lalijiwa. Rates of infestation of fruits of these two Mangifera spp by tephritid fruit flies have not previously been reported. PMID:28890657

Nematode suppression and growth stimulation in corn plants (Zea mays L.) irrigated with domestic effluent.

Science.gov (United States)

Barros, Kenia Kelly; do Nascimento, Clístenes Williams Araújo; Florencio, Lourdinha

2012-01-01

Treated wastewater has great potential for agricultural use due to its concentrations of nutrients and organic matter, which are capable of improving soil characteristics. Additionally, effluents can induce suppression of plant diseases caused by soil pathogens. This study evaluates the effect of irrigation with effluent in a UASB reactor on maize (Zea mays L.) development and on suppression of the diseases caused by nematodes of the genus Meloidogyne. Twelve lysimeters of 1 m(3) each were arranged in a completely randomized design, with four treatments and three replicates. The following treatments were used: T1 (W+I), irrigation with water and infestation with nematodes; T2 (W+I+NPK), irrigation with water, infestation with nematodes and fertilization with nitrogen (N), phosphorus (P) and potassium (K); T3 (E+I), irrigation with effluent and infestation with nematodes; and T4 (E+I+P), irrigation with effluent, infestation with nematodes and fertilization with phosphorus. The plants irrigated with the effluent plus the phosphorus fertilizer had better growth and productivity and were more resistant to the disease symptoms caused by the nematodes. The suppression levels may have been due to the higher levels of Zn and NO(3)(-) found in the leaf tissue of the plants irrigated with the effluent and phosphorus fertilizer.

Factors influencing the prevalence and infestation levels of Varroa destructor in honeybee colonies in two highland agro-ecological zones of Uganda.

Science.gov (United States)

Chemurot, Moses; Akol, Anne M; Masembe, Charles; de Smet, Lina; Descamps, Tine; de Graaf, Dirk C

2016-04-01

Varroa mites are ecto-parasites of honeybees and are a threat to the beekeeping industry. We identified the haplotype of Varroa mites and evaluated potential factors that influence their prevalence and infestation levels in the eastern and western highland agro-ecological zones of Uganda. This was done by collecting samples of adult worker bees between December 2014 and September 2015 in two sampling moments. Samples of bees were screened for Varroa using the ethanol wash method and the mites were identified by molecular techniques. All DNA sequences obtained from sampled mite populations in the two zones were 100 % identical to the Korean Haplotype (AF106899). Mean mite prevalence in the apiaries was 40 and 53 % for the western and eastern zones, respectively, during the first sampling. Over the second sampling, mean mite prevalence increased considerably in the western (59 %) but not in the eastern (51 %) zone. Factors that were associated with Varroa mite infestation levels include altitude, nature of apiary slope and apiary management practices during the first sampling. Our results further showed that Varroa mites were spreading from lower to higher elevations. Feral colonies were also infested with Varroa mites at infestation levels not significantly different from those in managed colonies. Colony productivity and strength were not correlated to mite infestation levels. We recommend a long-term Varroa mite monitoring strategy in areas of varying landscape and land use factors for a clear understanding of possible changes in mite infestation levels among African honeybees for informed decision making.

Borrelia burgdorferi sensu lato spirochetes in wild birds in northwestern California: associations with ecological factors, bird behavior and tick infestation.

Science.gov (United States)

Newman, Erica A; Eisen, Lars; Eisen, Rebecca J; Fedorova, Natalia; Hasty, Jeomhee M; Vaughn, Charles; Lane, Robert S

2015-01-01

Although Borrelia burgdorferi sensu lato (s.l.) are found in a great diversity of vertebrates, most studies in North America have focused on the role of mammals as spirochete reservoir hosts. We investigated the roles of birds as hosts for subadult Ixodes pacificus ticks and potential reservoirs of the Lyme disease spirochete B. burgdorferi sensu stricto (s.s.) in northwestern California. Overall, 623 birds representing 53 species yielded 284 I. pacificus larvae and nymphs. We used generalized linear models and zero-inflated negative binomial models to determine associations of bird behaviors, taxonomic relationships and infestation by I. pacificus with borrelial infection in the birds. Infection status in birds was best explained by taxonomic order, number of infesting nymphs, sampling year, and log-transformed average body weight. Presence and counts of larvae and nymphs could be predicted by ground- or bark-foraging behavior and contact with dense oak woodland. Molecular analysis yielded the first reported detection of Borrelia bissettii in birds. Moreover, our data suggest that the Golden-crowned Sparrow (Zonotrichia atricapilla), a non-resident species, could be an important reservoir for B. burgdorferi s.s. Of 12 individual birds (9 species) that carried B. burgdorferi s.l.-infected larvae, no birds carried the same genospecies of B. burgdorferi s.l. in their blood as were present in the infected larvae removed from them. Possible reasons for this discrepancy are discussed. Our study is the first to explicitly incorporate both taxonomic relationships and behaviors as predictor variables to identify putative avian reservoirs of B. burgdorferi s.l. Our findings underscore the importance of bird behavior to explain local tick infestation and Borrelia infection in these animals, and suggest the potential for bird-mediated geographic spread of vector ticks and spirochetes in the far-western United States.

Pollution externalities in a Schumpeterian growth model

OpenAIRE

Koesler, Simon

2010-01-01

This paper extends a standard Schumpeterian growth model to include an environmental dimension. Thereby, it explicitly links the pollution intensity of economic activity to technological progress. In a second step, it investigates the effect of pollution on economic growth under the assumption that pollution intensities are related to technological progress. Several conclusions emerge from the model. In equilibrium, the economy follows a balanced growth path. The effect of pollution on the ec...

Influence des herbicides sur l'infestation par les adventices, la ...

African Journals Online (AJOL)

SARAH

30 juin 2015 ... Keywords: Wheat, herbicides, weed, density, dry matter. INTRODUCTION. Une des raisons majeures de la chute des rendements des cultures céréalières comme les blés dans la zone «non chernozem» de la Russie et le reste du monde, demeure une forte infestation par différentes espèces adventices.

First record of Megaselia scalaris (Loew (Diptera: Phoridae infesting laboratory stocks of mantids (Parastagmatoptera tessellata, Saussure

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N. Mongiardino Koch

2013-03-01

Full Text Available We report the first record of Megaselia scalaris (Loew infesting laboratory stocks of the praying mantis (Parastagmatoptera tessellata, Saussure. M. scalaris, the scuttle fly, is a cosmopolitan species with a broad niche as it performs as detritivore, facultative parasite, and parasitoid. M. scalaris larvae were found feeding inside adult mantids and, when development was completed, pupae were found inside the abdominal cavity and around the body. We discuss the presence of colonies of crickets bred as prey for the mantids as a facilitator of M. scalaris infestation.

Mosquito larval productivity in rice-fields infested with Azolla in Mvomero District, Tanzania.

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Mwingira, V S; Mayala, B K; Senkoro, K P; Rumisha, S F; Shayo, E H; Mlozi, M R S; Mboera, L E G

2009-01-01

Azolla (Salviniales: Azollaceae) is known to reduce oviposition and adult emergence of a number of mosquito species. Several species of Azolla are reportedly indigenous to Tanzania. However, the potential of Azolla as a biocontrol agent against malaria mosquitoes has not been evaluated in the country. This cross-sectional study was carried out to assess mosquito larval productivity in irrigated rice-fields infested with Azolla in Mvomero District, Tanzania. A systematic larval sampling covering all open water bodies along designed transect was carried in rice-fields. Larval density was estimated by dipping water bodies with or without Azolla. The degree of Azolla coverage was categorized as 0%, 80%. Larvae densities were categorised as low ( or = 500/m2) productivity. A total of 120 water bodies were surveyed and 105 (87.5%) had Azolla microphyla and A. pinnata at varying degrees of coverage. Of the total 105 water bodies with Azolla, 80 (76.2%) had a green Azolla mat, and 25 (23.8%) a brown Azolla mat. Eighty-eight (73.3%) of the sites were infested with anophelines and 109 (90.8%) with culicine larvae. Seventy percent of all water bodies contained anophelines and culicines in sympatric breeding, while 20.8% and 3.3% had only culicines and anophelines, respectively. The majority (82%) of mosquito breeding sites were found in area with Azolla substrate. Mosquito larva productivity was low in sites with highest (>80%) Azolla coverage. Seventy-two (81.8%) of the anopheline and 90 (82.6%) culicine breeding sites were infested with Azolla. Water bodies infested with green Azolla were more productive than those covered by brown coloured Azolla substrates for both culicines (13%) and anophelines (8%). Of the 1537 field collected larvae that hatched to adult stage, 646 (42.03%) were Anopheles gambiae s.l., 42 (2.73%) were An. funestus and 769 (50.03%) were Culex quinquefasciatus. These findings suggest that the mosquito productivity is low when the Azolla coverage is high

Mechanistic model for microbial growth on hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Mallee, F M; Blanch, H W

1977-12-01

Based on available information describing the transport and consumption of insoluble alkanes, a mechanistic model is proposed for microbial growth on hydrocarbons. The model describes the atypical growth kinetics observed, and has implications in the design of large scale equipment for single cell protein (SCP) manufacture from hydrocarbons. The model presents a framework for comparison of the previously published experimental kinetic data.

Prevention of head louse infestation: a randomised, double-blind, cross-over study of a novel concept product, 1% 1,2-octanediol spray versus placebo.

Science.gov (United States)

Burgess, Ian F; Brunton, Elizabeth R; French, Rebecca; Burgess, Nazma A; Lee, Peter N

2014-05-30

To determine whether regular use of a spray containing 1,2-octanediol 1%, which has been shown to inhibit survival of head lice, is able to work as a preventive against establishment of new infestations. Randomised, double-blind, cross-over, community study in Cambridgeshire, UK. 63 male and female schoolchildren aged 4-16 years judged to have a high risk of recurrent infestation. Only the youngest member of a household attending school participated. Participants were treated to eliminate lice, randomised between 1% octanediol or placebo sprays for 6 weeks then crossed-over to the other spray for 6 weeks. Parents applied the sprays at least twice weekly or more frequently if the hair was washed. Investigators monitored weekly for infestation and replenished supplies of spray. The primary endpoint was the time taken until the first infestation event occurred. The secondary measure was safety of the product in regular use. Intention-to-treat analysis found a total of 32 confirmed infestations in 20 participants, with 9 of them infested while using both products. In these nine participants the time to first infestation showed a significant advantage to 1% octanediol (p=0.0129). Per-protocol analysis showed only trends because the population included was not large enough to demonstrate significance. There were no serious adverse events and only two adverse events possibly related to treatment, one was a case of transient erythema and another of a rash that resolved after 5 days. Routine use of 1% octanediol spray provided a significant level of protection from infestation. It was concluded that this product is effective if applied regularly and thoroughly. ISRCTN09524995. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Value function in economic growth model

Science.gov (United States)

Bagno, Alexander; Tarasyev, Alexandr A.; Tarasyev, Alexander M.

2017-11-01

Properties of the value function are examined in an infinite horizon optimal control problem with an unlimited integrand index appearing in the quality functional with a discount factor. Optimal control problems of such type describe solutions in models of economic growth. Necessary and sufficient conditions are derived to ensure that the value function satisfies the infinitesimal stability properties. It is proved that value function coincides with the minimax solution of the Hamilton-Jacobi equation. Description of the growth asymptotic behavior for the value function is provided for the logarithmic, power and exponential quality functionals and an example is given to illustrate construction of the value function in economic growth models.

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

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

2012-05-01

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

A Model of Controlled Growth

Science.gov (United States)

Bressan, Alberto; Lewicka, Marta

2018-03-01

We consider a free boundary problem for a system of PDEs, modeling the growth of a biological tissue. A morphogen, controlling volume growth, is produced by specific cells and then diffused and absorbed throughout the domain. The geometric shape of the growing tissue is determined by the instantaneous minimization of an elastic deformation energy, subject to a constraint on the volumetric growth. For an initial domain with C}^{2,α boundary, our main result establishes the local existence and uniqueness of a classical solution, up to a rigid motion.

Trajectories and models of individual growth

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Arseniy Karkach

2006-11-01

Full Text Available It has long been recognized that the patterns of growth play an important role in the evolution of age trajectories of fertility and mortality (Williams, 1957. Life history studies would benefit from a better understanding of strategies and mechanisms of growth, but still no comparative research on individual growth strategies has been conducted. Growth patterns and methods have been shaped by evolution and a great variety of them are observed. Two distinct patterns - determinate and indeterminate growth - are of a special interest for these studies since they present qualitatively different outcomes of evolution. We attempt to draw together studies covering growth in plant and animal species across a wide range of phyla focusing primarily on the noted qualitative features. We also review mathematical descriptions of growth, namely empirical growth curves and growth models, and discuss the directions of future research.

Comparison of percent hatch and fungal infestation in channel catfish eggs after copper sulfate, diquat bromide, formalin, and hydrogen peroxide treatment

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Reduced survival is often a result of fungal (Saprolegnia spp.) infestation of fish eggs. However, timely chemical treatments often limit these infestations and increase survival. The effect of copper sulfate pentahydrate (CSP - 10 mg/L), diquat bromide (25 mg/L diquat cation), formalin (433 mg/L)...

Reed canary grass observations of effects on crop stand and fibre quality caused by infestation of Epicalamus phalaridis

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S. HELLQVIST

2008-12-01

Full Text Available A severe infestation of the gall midge Epicalamus phalaridis (Diptera: Cecidomyiidaeoccurred in a field of reed canary grass, Phalaris arundinacea in northern Sweden. The midge species has potential to become a serious pest on Phalaris grown for bioenergy or fibre production. Larvae of the midge feed beneath leaf sheaths and the crop lodges in late summer. Details are given on the biology of the midge. In the infested field, population densities of the midge were very high during three consecutive years. The crop was weakened and the occurrence of weeds increased. The dry matter yields declined markedly and were after three years of midge-attack about 50% of the average yield in the preceding years. The yield dropped comparatively more when the crop was harvested in the spring as opposed to harvest in late autumn and more at a nitrogen fertilisation at 100 kg compared to 200 kg N ha–1 per year. The effect of midge attack on fibre quality was studied. The fibre properties of midge-infested parts of internodes were poor, but as midge-damaged parts are brittle, they could probably be sorted out in a fractionation process. Undamaged parts of infested internodes had the same fibre properties as those from an uninfested crop.;

Role of syrphid larvae and other predators in suppressing aphid infestations in organic lettuce on California's Central Coast.

Science.gov (United States)

Smith, Hugh A; Chaney, William E; Bensen, Tiffany A

2008-10-01

Organic lettuce, Lactuca sativa L., growers on the Central Coast of California rely on conservation biological control to manage Nasonovia ribisnigri Mosley (Hemiptera: Aphididae) and other aphid pests of lettuce. In 2006, we carried out five replicated field trials to determine the importance of syrphid larvae in the suppression of N. ribisnigri and other aphids infesting organic romaine lettuce. We used Entrust, a spinosad-based insecticide approved for use on organic farms, to suppress syrphid larvae in aphid-infested romaine. Romaine treated with Entrust was unmarketable at harvest because of aphid infestation, whereas insecticide-free romaine was marketable. Syrphid larvae composed 85% or more of total predators in most trials, and they were the only predators consistently recovered from romaine that was infested with aphids early and largely aphid-free by harvest. The species mix of nonsyrphid predators varied from site to site. Applications of Entrust suppressed nonsyrphid predators in two trials, and so was an imperfect tool for selectively suppressing syrphid larvae. The relative importance of syrphid larvae and other predators in the conservation biological control of aphids in organic romaine is discussed. We conclude that syrphid larvae are primarily responsible for the suppression of aphids in organic romaine on California's Central Coast.

Infestation dynamics of the Asian longhorned beetle in the United States

Science.gov (United States)

Alan Sawyer

2007-01-01

The Asian longhorned beetle (ALB), Anoplophora glabripennis (Coleoptera: Cerambycidae), is an exotic pest of Asian origin, first discovered in North America (Brooklyn, NY) in 1996. That infestation has now spread to Queens, Manhattan and Long Island, NY and Jersey City, NJ. Based on DNA profiles (Carter et al. 2005) and other evidence, independent...

The effect of Sirex noctilio infestation and fire damage on the ...

African Journals Online (AJOL)

The infection and association between the wood wasp Sirex noctilio and the fungus Amylostereum areolatum is responsible for large-scale tree mortality in the Midlands of the KwaZulu-Natal province in South Africa. An exploratory investigation on the effect of the infestation of trees by the wood wasp and its associated ...

Effects of gypsy moth infestation on aesthetic preferences and behavior intentions

Science.gov (United States)

Samuel M. Brock; Steve Hollenhorst; Wayne Freimund

1991-01-01

Using the Scenic Beauty Estimator (SBE) approach, within-stand color photographs were taken of 27 forested sites representative of the Central Appalachian Plateau. These sites had been repeatedly infested by gypsy moth (Lymantria dispar) (GM) to varying degrees since 1985, with resulting tree mortality from 6% - 97%. Eighty-one slides (3 slides/site...

Modeling error distributions of growth curve models through Bayesian methods.

Science.gov (United States)

Zhang, Zhiyong

2016-06-01

Growth curve models are widely used in social and behavioral sciences. However, typical growth curve models often assume that the errors are normally distributed although non-normal data may be even more common than normal data. In order to avoid possible statistical inference problems in blindly assuming normality, a general Bayesian framework is proposed to flexibly model normal and non-normal data through the explicit specification of the error distributions. A simulation study shows when the distribution of the error is correctly specified, one can avoid the loss in the efficiency of standard error estimates. A real example on the analysis of mathematical ability growth data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99 is used to show the application of the proposed methods. Instructions and code on how to conduct growth curve analysis with both normal and non-normal error distributions using the the MCMC procedure of SAS are provided.

Induction of direct and indirect plant responses by jasmonic acid, low spider mite densities, or a combination of jasmonic acid treatment and spider mite infestation.

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Gols, Rieta; Roosjen, Mara; Dijkman, Herman; Dicke, Marcel

2003-12-01

Jasmonic acid (JA) and the octadecanoid pathway are involved in both induced direct and induced indirect plant responses. In this study, the herbivorous mite, Tetranychus urticae, and its predator, Phytoseiulus persimilis, were given a choice between Lima bean plants induced by JA or spider mites and uninduced control plants. Infestation densities resulting in the induction of predator attractants were much lower than thus far assumed, i.e., predatory mites were significantly attracted to plants that were infested for 2 days with only one or four spider mites per plant. Phytoseiulus persimilis showed a density-dependent response to volatiles from plants that were infested with different numbers of spider mites. Similarly, treating plants with increasing concentrations of JA also led to increased attraction of P. persimilis. Moreover, the duration of spider mite infestation was positively correlated with the proportion of predators that were attracted to mite-infested plants. A pretreatment of the plants with JA followed by a spider mite infestation enhanced the attraction of P. persimilis to plant volatiles compared to attraction to volatiles from plants that were only infested with spider mites and did not receive a pretreatment with JA. The herbivore, T. urticae preferred leaf tissue that previously had been infested with conspecifics to uninfested leaf tissue. In the case of choice tests with JA-induced and control leaf tissue, spider mites slightly preferred control leaf tissue. When spider mites were given a choice between leaf discs induced by JA and leaf discs damaged by spider mite feeding, they preferred the latter. The presence of herbivore induced chemicals and/or spider mite products enhanced settlement of the mites, whereas treatment with JA seemed to impede settlement.

Patterns of infestation by chigger mites in four diurnal lizard species from a restinga habitat (Jurubatiba of Southeastern Brazil

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M. Cunha-Barros

Full Text Available We studied the parasitism by larvae of the chigger mite Eutrombicula alfreddugesi on the lizard community of Restinga de Jurubatiba, Rio de Janeiro State, Southeastern Brazil. We investigated the patterns of infestation (prevalence and intensity of chigger mites in four sympatric lizards: Tropidurus torquatus, Mabuya agilis, M. macrorhyncha and Cnemidophorus littoralis. All lizards collected were checked for the presence of mites, which were counted under stereomicroscope. We tested the relationship between intensity of infestation and lizard body size for each species using regression analysis. The prevalences and mean intensities (+ one standard deviation of infestation on each host species were, respectively: 100%; 86.4 + 94.6 in T. torquatus (n = 62; 100%; 20.9 + 9.3 in M. agilis (n = 7; 100%; 11.1 + 13.1 in M. macrorhyncha (n = 12; and 95.2%; 19.1 + 16.8 in C. littoralis (n = 21. Only for C. littoralis did body size significantly affect the intensity of infestation (r = 0.27, p = 0.02. For all lizard species, the body parts where chiggers occurred with the highest intensity were those of skin folds and joint regions.

Weed infestation of field crops in different soils in the protective zone of Roztocze National Park. Part II. Root crops

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Marta Ziemińska-Smyk

2013-12-01

Full Text Available The study on weed infestation of root crops in different soils in the protective zone of Roztocze National Park was conducted in the years 1991-1995. As many as 240 phytosociological records, made with the use of Braun-Blanquet method, were taken in potato and sugar beet fields. The number of weed species in sugar beet and potato in the area depended on the soil and type of root crop. In the same environment conditions. the iiuinber of weed species was higher in potato than in sugar beet. The most difficult weed species iii all types of soil were: Chenopodium album, Stellaria media and Convolvulus arvensis. Podsolic soils were highly infested by two acidophylic species: Spergula arvensis and Raphanus raphanistum. Potato in loess soil and brown soil made of loamy sands were highly infested by Echinochloa crus-galli, Equisetum arvense and Galinsoga parviflora. Root crop plantations in brown soils formed from gaizes of granulometric loam texture and limestone soils were infested by: Galium aparine, Sonchus arvensis, Sinapis arvensis and Veronica persica.

The effect of intercropping on weed infestation of a spring barley crop cultivated in monoculture

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Ewa Kwiecińska-Poppe

2012-12-01

Full Text Available This paper presents the results of a study carried out in the years 2005-2007 in the Bezek Experimental Farm near the city of Chełm, Poland, on heavy mixed rendzina soil. The effect of intercropping, using red clover (cv. Dajana and white clover (cv. Astra, on weed infestation of a spring barley crop was studied. The species composition of weeds in the spring barley crop changed to a small extent under the influence of the application of clover intercropping, whereas the population size of particular species showed large fluctuations. In the spring barley crop with the red clover intercrop, Sonchus arvensis occurred in greatest numbers among dicotyledonous weed species. In the barley crop with white clover and without intercrop, Viola arvensis and Sonchus arvensis were the dominant dicotyledonous species. Setaria pumila was the dominant monocotyledonous species in all the treatments. Intercropping using red and white clover clearly limited the growth and development of weeds. The red clover intercrop in the spring barley crop better reduced the infestation with dicotyledonous weeds and also significantly reduced the number of monocotyledonous weeds and the total number of weeds, whereas the white clover intercrop limited only the number of monocotyledonous weeds. The application of the herbicide Chwastox Extra 300 SL significantly reduced the fresh weight of weeds found in the spring barley crop. The presence of the intercrop resulted in different total numbers of weeds in particular treatments. Intercropping distinctly limited the occurrence of the following weed species: Sonchus arvensis, Fallopia convolvulus, Melandrium album, Amaranthus retroflexus, Veronica arvensis and Medicago lupulina. The investigated intercrop species also reduced the biomass of weeds. The application of the herbicide did not differentiate the number of monocotyledonous weeds, which resulted from the application of Chwastox Extra 300 SL that controls only

Settling and growth of D. polymorpha in the raw water circuits of the Cattenom nuclear power plant (Moselle, France); Fixation et croissance de D. Polymorpha dans les circuits d`eau brute de la centrale nucleaire de Cattenom

Energy Technology Data Exchange (ETDEWEB)

Moreteau, J C; Khalanski, M

1994-05-01

A``biological profile`` of the zebra mussels which are infesting certain circuits of the Cattenom nuclear power plant has been provided by data collected during a three-year measurement programme (1991-1993). The larval settlement periods and the growth of settled mussels were monitored. A simple mathematical model, which calculates the shell growth on the long term, was calibrated with the field data. It is based on three functions representing the effect of the initial size, water temperature and fool availability (plankton chlorophyll a). (authors). 13 refs., 7 figs., 4 tabs.

On Latent Growth Models for Composites and Their Constituents.

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Hancock, Gregory R; Mao, Xiulin; Kher, Hemant

2013-09-01

Over the last decade and a half, latent growth modeling has become an extremely popular and versatile technique for evaluating longitudinal change and its determinants. Most common among the models applied are those for a single measured variable over time. This model has been extended in a variety of ways, most relevant for the current work being the multidomain and the second-order latent growth models. Whereas the former allows for growth function characteristics to be modeled for multiple outcomes simultaneously, with the degree of growth characteristics' relations assessed within the model (e.g., cross-domain slope factor correlations), the latter models growth in latent outcomes, each of which has effect indicators repeated over time. But what if one has an outcome that is believed to be formative relative to its indicator variables rather than latent? In this case, where the outcome is a composite of multiple constituents, modeling change over time is less straightforward. This article provides analytical and applied details for simultaneously modeling growth in composites and their constituent elements, including a real data example using a general computer self-efficacy questionnaire.

Structural modelling of economic growth: Technological changes

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Sukharev Oleg

2016-01-01

Full Text Available Neoclassical and Keynesian theories of economic growth assume the use of Cobb-Douglas modified functions and other aggregate econometric approaches to growth dynamics modelling. In that case explanations of economic growth are based on the logic of the used mathematical ratios often including the ideas about aggregated values change and factors change a priori. The idea of assessment of factor productivity is the fundamental one among modern theories of economic growth. Nevertheless, structural parameters of economic system, institutions and technological changes are practically not considered within known approaches, though the latter is reflected in the changing parameters of production function. At the same time, on the one hand, the ratio of structural elements determines the future value of the total productivity of the factors and, on the other hand, strongly influences the rate of economic growth and its mode of innovative dynamics. To put structural parameters of economic system into growth models with the possibility of assessment of such modes under conditions of interaction of new and old combinations is an essential step in the development of the theory of economic growth/development. It allows forming stimulation policy of economic growth proceeding from the structural ratios and relations recognized for this economic system. It is most convenient in such models to use logistic functions demonstrating the resource change for old and new combination within the economic system. The result of economy development depends on starting conditions, and on institutional parameters of velocity change of resource borrowing in favour of a new combination and creation of its own resource. Model registration of the resource is carried out through the idea of investments into new and old combinations.

Health impacts of bedbug infestation: A case of five towns in Amhara ...

African Journals Online (AJOL)

user

areas were not considered as infestation in the study. Pretested structured questionnaire was the instrument used to gather demographic information from the household representatives. In addition, Diagnostic and. Statistical Manual of Mental Disorders (DSM-5) (21) was employed to assess the psychological and social.

Suppression of Phytophthora ramorum infestations through silvicultural treatment in California's north coast

Science.gov (United States)

Yana Valachovic; Chris Lee; Brendan Twieg; David Rizzo; Richard Cobb; Radoslaw Glebocki

2013-01-01

In 2006, three forested sites infested with Phytophthora ramorum in Humboldt County, California were subjected to different combinations of treatments designed to reduce inoculum and control spread. One treatment, consisting of removal of all California bay laurel (Umbellularia californica (Hook. & Arn.) Nutt.) and tanoak...

Efficacy and safety assessment of a water-soluble formulation of fluralaner for treatment of natural Ornithonyssus sylviarum infestations in laying hens

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Nancy C. Hinkle

2018-02-01

Full Text Available Abstract Background Northern fowl mite, Ornithonyssus sylviarum (Canestrini & Fanzago, 1877, infestations can stress birds, impairing welfare and causing substantial economic losses. A study was undertaken to determine the efficacy of an ectoparasiticide solution (fluralaner for oral administration in the treatment of mite-infested hens. Methods Clinically healthy, naturally mite-infested laying hens (n = 132, approximately 32 weeks of age, were ranked by Day -9 mite vent counts and randomized among 12 study pens, each to hold one of four treatment groups. Three groups received fluralaner-medicated water by oral gavage at dose rates of 0.25, 0.5 or 1.0 mg/kg on Days 0 and 7; one group was an untreated control (three pens for each group. Five naturally infested untreated birds were included in each pen to act as mite-infested source birds. Thus each pen, treated and control, had six non-source birds for assessment of efficacy, plus five source birds to provide ongoing challenge. Primary efficacy assessments were based on mean O. sylviarum vent counts from non-source birds in the control and treated group pens on Days 1, 2, 6, 8, 12, 15, 19, 22 and 26. Results Source-birds maintained infestations throughout the study, validating the challenge to study birds. On Days 1 through 22, mean control group mite counts were significantly greater than those of the treated groups (P ≤ 0.013. Relative to the control group, mean O. sylviarum counts were reduced by at least 90% from Day 6 through Days 19, 22 and 22 in the fluralaner 0.25, 0.5 and 1.0 mg/kg groups, respectively. On Day 19, mean mite counts were lower in the 0.5 and 1.0 mg/kg groups compared with the 0.25 mg/kg group (P ≤ 0.018, and in the 1.0 mg/kg compared with the 0.5 mg/kg group (P = 0.014. There were no adverse events in treated birds. Conclusions A fluralaner solution administered twice by gavage to laying hens with a one-week between-treatment interval was safe

Abundance of Armillaria within old-growth eastern hemlock stands in South-Central Pennsylvania

Science.gov (United States)

Matthew S. Fromm; Donald D. Davis

2007-01-01

Abstract—In early summer 2002, 329 soil-sampling pits were dug within an old-growth, eastern hemlock (Tsuga canadensis [L.] Carrière) stand in south-central Pennsylvania recently infested with the hemlock woolly adelgid (Adelges tsugae Annand). For comparison, 199 similar pits were dug in an adjacent hardwood stand. Rhizomorphs of...

Dynamique d'infestation de la forêt classée de Sanaimbo par les adventices à partir des agro-écosystèmes environnants

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Touré, A.

2016-01-01

Full Text Available Dynamics of Infestation in the Sanaimbo Protected Forest by Weeds from Surrounding Agro-ecosystems. The infestation dynamics of the Sanaimbo Protected Forest by weeds was evaluated with the aim to quantify the impact of weeds on the original flora of this locality. Floristic and phytosociological surveys samples were carried out on plots located inside and outside the forest. The frequency and proportion of biological types is different in plots located outside and within the classified forest. Chromolaena odorata (L. King & H.E. Robins has a high degree of infestation whatever the plot location. Euphorbia heterophylla L., Ageratum conyzoides L. and Panicum laxum Sw. show high levels of infestation in the plots out of the forest and start invading slowly the plots within the forest.

Model uncertainty in growth empirics

NARCIS (Netherlands)

Prüfer, P.

2008-01-01

This thesis applies so-called Bayesian model averaging (BMA) to three different economic questions substantially exposed to model uncertainty. Chapter 2 addresses a major issue of modern development economics: the analysis of the determinants of pro-poor growth (PPG), which seeks to combine high

Effect of feeding Mucuna pruriens on helminth parasite infestation in lambs.

Science.gov (United States)

Huisden, C M; Adesogan, A T; Gaskin, J M; Courtney, C H; Raji, A M; Kang, T

2010-02-17

Mucuna pruriens is a tropical legume anecdotally reputed to have anthelmintic properties. This study was conducted to examine the validity of such claims. The aim of this study was to determine if ingestion of Mucuna seeds reduces helminth parasite infestation in lambs. Thirty-six Dorper x Katahdin ram lambs were assigned to three treatments, a cottonseed meal based control diet, a diet in which Mucuna replaced cottonseed meal and the control diet with levamisole (7.5mg/kg body weight) administration. All diets were isonitrogenous and isocaloric. The 12 lambs in each treatment were assigned randomly to 4 pens, each containing 3 lambs. Lambs were trickle infected three times per week by gavage with infectious Haemonchus contortus larvae (2000 larvae/lamb) for 3 weeks. Levamisole treatment decreased fecal egg counts by 87% and abomasal worm counts by 83%. Mucuna intake did not statistically affect fecal egg counts or abomasal worm counts, though numerical (P>0.10) reductions of 7.4% and 18.1%, respectively were evident. Anemia indicators, feed intake, and lamb growth were unaffected by treatment. Levamisole reduced the Haemonchus parasite burden in lambs significantly but feeding Mucuna reduced the burden by levels unlikely to eliminate the clinical effects of parasitism. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Influence of Agronomic and Climatic Factors on Fusarium Infestation and Mycotoxin Contamination of Cereals in Norway

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Bernhoft, A.; Torp, M.; Clasen, P.-E.; Løes, A.-K.; Kristoffersen, A.B.

2012-01-01

A total of 602 samples of organically and conventionally grown barley, oats and wheat was collected at grain harvest during 2002–2004 in Norway. Organic and conventional samples were comparable pairs regarding cereal species, growing site and harvest time, and were analysed for Fusarium mould and mycotoxins. Agronomic and climatic factors explained 10–30% of the variation in Fusarium species and mycotoxins. Significantly lower Fusarium infestation and concentrations of important mycotoxins were found in the organic cereals. The mycotoxins deoxynivalenol (DON) and HT-2 toxin (HT-2) constitute the main risk for human and animal health in Norwegian cereals. The impacts of various agronomic and climatic factors on DON and HT-2 as well as on their main producers F. graminearum and F. langsethiae and on total Fusarium were tested by multivariate statistics. Crop rotation with non-cereals was found to reduce all investigated characteristics significantly – mycotoxin concentrations as well as various Fusarium infestations. No use of mineral fertilisers and herbicides was also found to decrease F. graminearum, whereas lodged fields increased the occurrence of this species. No use of herbicides was also found to decrease F. langsethiae, but for this species the occurrence was lower in lodged fields. Total Fusarium infestation was decreased with no use of fungicides or mineral fertilisers, and with crop rotation, as well as by using herbicides and increased by lodged fields. Clay and to some extent silty soils seemed to reduce F. graminearum in comparison with sandy soils. Concerning climate factors, low temperature before grain harvest was found to increase DON; and high air humidity before harvest to increase HT-2. F. graminearum was negatively correlated with precipitation in July but correlated with air humidity before harvest. F. langsethiae was correlated with temperature in July. Total Fusarium increased with increasing precipitation in July. Organic cereal

Comparison of different methods for ectoparasite infestation detection in Laboratory bred animals and standardization of their health certificate

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mohammad Abdigoudarzi

2014-05-01

Full Text Available In order to study external parasites of laboratory reared animals at Razi institute, different methods including brushing of animal's surface body, cellophane tape of body surface, peri-anal cellophane tape test (CTT and skin scrapings and digestive method were applied and collected samples were studied. In addition, field collected rats were tested using brushing method. One mouse had been infested by some mites. Rabbits, rats, mice and guinea pigs had not been infested with external parasites. Field collected rats had been highly infested with mites from the family Laelapidae. The, brushing method was confirmed to be a useful method for mite detection. According to the methods used in this study and these recommended by SOP from international animal breeding centers the CTT method was proposed to be useful for preparing health certificate of laboratory animals at the department of laboratory animal breading at Razi institute.

Detecting Growth Shape Misspecifications in Latent Growth Models: An Evaluation of Fit Indexes

Science.gov (United States)

Leite, Walter L.; Stapleton, Laura M.

2011-01-01

In this study, the authors compared the likelihood ratio test and fit indexes for detection of misspecifications of growth shape in latent growth models through a simulation study and a graphical analysis. They found that the likelihood ratio test, MFI, and root mean square error of approximation performed best for detecting model misspecification…

Southern pine beetle infestation probability mapping using weights of evidence analysis

Science.gov (United States)

Jason B. Grogan; David L. Kulhavy; James C. Kroll

2010-01-01

Weights of Evidence (WofE) spatial analysis was used to predict probability of southern pine beetle (Dendroctonus frontalis) (SPB) infestation in Angelina, Nacogdoches, San Augustine and Shelby Co., TX. Thematic data derived from Landsat imagery (1974–2002 Landsat 1–7) were used. Data layers included: forest covertype, forest age, forest patch size...

Seasonal variation of infestation by ectoparasitic chigger mite larvae (Acarina: Trombiculidae) on resident and migratory birds in coffee agroecosystems of Chiapas, Mexico.

Science.gov (United States)

Dietsch, Thomas V

2005-12-01

Parasitism is not well documented for birds found in tropical habitats. Long-distance migratory birds may face additional risks to an already hazardous journey when infected. This study explores the ecology of an ectoparasite infestation in Chiapas, Mexico. During a mist-netting project in 2 different coffee management systems, chigger mites (Acarina: Trombiculidae), ectoparasitic during the larval stage, were found on both resident and migratory birds. Using a rapid assessment protocol, it was observed that 17 of 26 species of long-distance migrants and 33 of 71 resident species had at least 1 infested individual. Infestation prevalences were unexpectedly high on some long-distance migrants, as high as 0.73 for Swainson's thrush (Catharus ustulatus), a value on par with heavily infested resident species. Prevalence was highest during winter sampling: 0.18 overall, 0.16 of migrants, and 0.23 of residents. Prevalence was 0.14 for resident birds during the summer breeding season. Mean abundance and mean intensity of infestation are reported for 97 species captured and inspected during the course of this study. In this region, chigger mite larvae are relatively common on birds and their abundance varies seasonally. High prevalence for some migratory birds suggests that more research and monitoring of ectoparasites are needed, especially in light of emerging diseases.

The efficacy of emamectin benzoate against infestations of Lepeophtheirus salmonis on farmed Atlantic salmon (Salmo salar L in Scotland, 2002-2006.

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Fiona Lees

Full Text Available BACKGROUND: Infestations of the parasitic copepod Lepeophtheirus salmonis, commonly referred to as sea lice, represent a major challenge to commercial salmon aquaculture. Dependence on a limited number of theraputants to control such infestations has led to concerns of reduced sensitivity in some sea lice populations. This study investigates trends in the efficacy of the in-feed treatment emamectin benzoate in Scotland, the active ingredient most widely used across all salmon producing regions. METHODOLOGY/PRINCIPAL FINDINGS: Study data were drawn from over 50 commercial Atlantic salmon farms on the west coast of Scotland between 2002 and 2006. An epi-informatics approach was adopted whereby available farm records, descriptive epidemiological summaries and statistical linear modelling methods were used to identify factors that significantly affect sea lice abundance following treatment with emamectin benzoate (SLICE(R, Schering Plough Animal Health. The results show that although sea lice infestations are reduced following the application of emamectin benzoate, not all treatments are effective. Specifically there is evidence of variation across geographical regions and a reduction in efficacy over time. CONCLUSIONS/SIGNIFICANCE: Reduced sensitivity and potential resistance to currently available medicines are constant threats to maintaining control of sea lice populations on Atlantic salmon farms. There is a need for on-going monitoring of emamectin benzoate treatment efficacy together with reasons for any apparent reduction in performance. In addition, strategic rotation of medicines should be encouraged and empirical evidence for the benefit of such strategies more fully evaluated.

The efficacy of emamectin benzoate against infestations of Lepeophtheirus salmonis on farmed Atlantic salmon (Salmo salar L) in Scotland, 2002-2006.

Science.gov (United States)

Lees, Fiona; Baillie, Mark; Gettinby, George; Revie, Crawford W

2008-02-06

Infestations of the parasitic copepod Lepeophtheirus salmonis, commonly referred to as sea lice, represent a major challenge to commercial salmon aquaculture. Dependence on a limited number of theraputants to control such infestations has led to concerns of reduced sensitivity in some sea lice populations. This study investigates trends in the efficacy of the in-feed treatment emamectin benzoate in Scotland, the active ingredient most widely used across all salmon producing regions. Study data were drawn from over 50 commercial Atlantic salmon farms on the west coast of Scotland between 2002 and 2006. An epi-informatics approach was adopted whereby available farm records, descriptive epidemiological summaries and statistical linear modelling methods were used to identify factors that significantly affect sea lice abundance following treatment with emamectin benzoate (SLICE(R), Schering Plough Animal Health). The results show that although sea lice infestations are reduced following the application of emamectin benzoate, not all treatments are effective. Specifically there is evidence of variation across geographical regions and a reduction in efficacy over time. Reduced sensitivity and potential resistance to currently available medicines are constant threats to maintaining control of sea lice populations on Atlantic salmon farms. There is a need for on-going monitoring of emamectin benzoate treatment efficacy together with reasons for any apparent reduction in performance. In addition, strategic rotation of medicines should be encouraged and empirical evidence for the benefit of such strategies more fully evaluated.

Modeling urban fire growth

International Nuclear Information System (INIS)

Waterman, T.E.; Takata, A.N.

1983-01-01

The IITRI Urban Fire Spread Model as well as others of similar vintage were constrained by computer size and running costs such that many approximations/generalizations were introduced to reduce program complexity and data storage requirements. Simplifications were introduced both in input data and in fire growth and spread calculations. Modern computational capabilities offer the means to introduce greater detail and to examine its practical significance on urban fire predictions. Selected portions of the model are described as presently configured, and potential modifications are discussed. A single tract model is hypothesized which permits the importance of various model details to be assessed, and, other model applications are identified

Detection of Leishmania infantum DNA in hamsters infested with ticks collected from naturally infected dogs

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Valter dos Anjos Almeida

2016-12-01

Full Text Available ABSTRACT. Almeida V. dos A., da Hora T.N., Leça Júnior N.F., Carvalho F.S., da Silva A.L., Wenceslau A.A., Albuquerque G.R. & Silva F.L. Detection of Leishmania infantum DNA in hamsters infested with ticks collected from naturally infected dogs. [Detecção do DNA de Leishmania infantum em hamsters infestados com carrapatos coletados de cães naturalmente infectados.] Revista Brasileira de Medicina Veterinária, 38(4:329-333, 2016. Departamento de Ciências Agrárias e Ambientais, Universidade Estadual de Santa Cruz, Campus Soane Nazaré de Andrade, Hospital Veterinário, Km 16, Rodovia Jorge Amado, Ilhéus, BA 45662-900, Brasil. E-mail: fabiana.lessa@gmail.com The aim of this study was to investigate the role of Rhipicephalus sanguineus, the brown dog tick, in the transmission of Leishmania infantum. To accomplish this, we used 24 adult golden hamsters of both genders, and divided them into two groups: a control group (n = 4 and an experimental group (n = 20. The animals from the experimental group were infested with ticks obtained from dogs naturally infected with L. infantum. Hamsters of the control group were not infested and were maintained at the same conditions, as the infested animals. After three months of observation, animals were euthanized and they were posted to obtain samples of their blood, spleen, liver, lymph nodes, and skin. These samples were then processed by histopathology, immunohistochemistry, and polymerase chain reaction (PCR. Fourteen hamsters (70% of the experimental group tested PCR-positive for L. infantum DNA in samples of buffy coat. The results of this study indicated that R. sanguineus ticks can transmit some forms or parts of L. infantum to parasitized hamsters.

PREVALENCE OF BABESIA SPP., EHRLICHIA SPP., AND TICK INFESTATIONS IN OKLAHOMA BLACK BEARS (URSUS AMERICANUS).

Science.gov (United States)

Skinner, Delaina; Mitcham, Jessica R; Starkey, Lindsay A; Noden, Bruce H; Fairbanks, W Sue; Little, Susan E

2017-10-01

American black bears (Ursus americanus) are commonly infested with ticks throughout their range, but there are few surveys for tick-borne disease agents in bears. To characterize tick infestations and determine the prevalence of current infection with Babesia spp. and past or current infection with Ehrlichia spp. in newly re-established populations of black bears in east central and southeastern Oklahoma, US, we identified adult (n=1,048) and immature (n=107) ticks recovered from bears (n=62). We evaluated serum and whole blood samples from a subset (n=49) for antibodies reactive to, and characteristic DNA fragments of, Ehrlichia spp., as well as characteristic DNA fragments of Babesia spp. Amblyomma americanum, the most common tick identified, was found on a majority (56/62; 90%) of bears and accounted for 697/1,048 (66.5%) of all ticks recovered. Other ticks included Dermacentor variabilis (338/1,048; 32.3%) from 36 bears, Amblyomma maculatum (9/1,048; 0.9%) from three bears, and Ixodes scapularis (4/1,048; 0.4%) from three bears. Antibodies reactive to Ehrlichia spp. were detected in every bear tested (49/49; 100%); maximum inverse titers to Ehrlichia chaffeensis ranged from 64-4,096 (geometric mean titer 1,525). However, PCR failed to identify active infection with E. chaffeensis, Ehrlichia ewingii, or an Ehrlichia ruminantium-like agent. Infection with Babesia spp. was detected by PCR in 3/49 (6%) bears. Together these data confirm that tick infestations and infection with tick-borne disease agents are common in bears in the southern US. The significance of these infestations and infections to the health of bears, if any, and the identity of the Ehrlichia spp. responsible for the antibody reactivity seen, warrant further evaluation.

Neo-logistic model for the growth of bacteria

OpenAIRE

Tashiro, Tohru; Yoshimura, Fujiko

2017-01-01

We propose a neo-logistic model that can describe bacterial growth data precisely. This model is not derived by modifying the logistic model formally, but by incorporating the synthesis of inducible enzymes into the logistic model indirectly. Therefore, the meaning of the parameters of the neo-logistic model becomes physically clear. The neo-logistic model can approximate bacterial growth better than models previously presented, and predict the order of the saturated number of bacteria in the...

Comparison of test methods for mould growth in buildings

DEFF Research Database (Denmark)

Bonderup, Sirid; Gunnarsen, Lars Bo; Knudsen, Sofie Marie

2016-01-01

renovation needs. This is of importance when hidden surface testing would require destructive measures and subsequent renovation. After identifying available methods on the Danish market for assessing mould growth in dwellings, a case study was conducted to test the usefulness of the methods in four......The purpose of this work is to compare a range of test methods and kits for assessing whether a building structure is infested by mould fungi. A further purpose of this work is to evaluate whether air-based methods for sampling fungal emissions provide information qualifying decisions concerning...... methods measure different aspects relating to mould growth and vary in selectivity and precision. The two types of air samples indicated low levels of mould growth, even where the results of the other methods indicated high to moderate growth. With methods based on culture and DNA testing some differences...

First record of Megaselia scalaris (Loew) (Diptera: Phoridae) infesting laboratory colonies of Triatoma brasiliensis Neiva (Hemiptera: Reduviidae)

International Nuclear Information System (INIS)

Costa, Jane; Almeida, Carlos E.; Esperanca, Gleidson M.; Morales, Ninive; Mallet, Jacenir R. dos S.; Goncalves, Teresa C.M.; Prado, Angelo P. do

2007-01-01

Megaselia scalaris (Loew) is a cosmopolitan and synanthropic scuttle fly, eclectic in its feeding habits and acts as detritivore, parasite, facultative parasite, and parasitoid. Here we report for the first time M. scalaris infesting laboratory colonies of Triatoma brasiliensis Neiva, the most important Chagas disease vector in semiarid areas of Brazil. M. scalaris larvae were found feeding inside bugs; pupae were found in the esophagus and intestinal regions of T. brasiliensis through dissection. Other relevant information about this finding is also described in this note, including some preventive measures to avoid laboratory colonies infestations. (author)

First record of Megaselia scalaris (Loew) (Diptera: Phoridae) infesting laboratory colonies of Triatoma brasiliensis Neiva (Hemiptera: Reduviidae)

Energy Technology Data Exchange (ETDEWEB)

Costa, Jane; Almeida, Carlos E.; Esperanca, Gleidson M.; Morales, Ninive [Instituto Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Dept.de Entomologia. Lab. da Colecao Entomologica; Mallet, Jacenir R. dos S.; Goncalves, Teresa C.M. [Instituto Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Lab. Transmissores de Leishmanioses. Nucleo de Ultraestrutura; Prado, Angelo P. do [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Inst. de Biologia. Dept. de Parasitologia

2007-11-15

Megaselia scalaris (Loew) is a cosmopolitan and synanthropic scuttle fly, eclectic in its feeding habits and acts as detritivore, parasite, facultative parasite, and parasitoid. Here we report for the first time M. scalaris infesting laboratory colonies of Triatoma brasiliensis Neiva, the most important Chagas disease vector in semiarid areas of Brazil. M. scalaris larvae were found feeding inside bugs; pupae were found in the esophagus and intestinal regions of T. brasiliensis through dissection. Other relevant information about this finding is also described in this note, including some preventive measures to avoid laboratory colonies infestations. (author)

Surveys for Stenoma catenifer (Lepidoptera: Elachistidae) and associated parasitoids infesting avocados in Perú.

Science.gov (United States)

Hoddle, Mark S; Hoddle, Christina D

2012-04-01

Surveys for Stenoma catenifer Walsingham, the avocado seed moth, and its associated larval parasitoids were conducted in the Departments of Junín, Huánuco, Cusco, and Madre de Dios in Perú. Fruit infestation levels in some areas ranged from 0 to 58%, and parasitism of S. catenifer larvae in Junín and Huánuco was 23%. Five species of hymenopteran parasitoid in two families, Braconidae (Apanteles sp., Hypomicrogaster sp., and Chelonus sp.) and Ichneumonidae (Pristeromerus sp. and Xiphosomella sp.), were reared from larvae, and one species of tachinid fly (Chrysodoria sp.) emerged from pupae. The dominant larval parasitoid, a gregarious Apanteles sp., accounted for 55% of parasitized hosts. Branch and twig tunneling by S. catenifer larvae in a commercial Hass avocado orchard was observed in Cusco. The field attractiveness of the sex pheromone of S. catenifer was demonstrated with 73% of monitoring traps deployed in three departments (Junín, Huánuco, and Cusco) catching male moths. Approximately 55% of avocado fruit sourced from the Province of Chanchamayo (Junin) and purchased at the Mercado Modelo de Frutas in La Victoria, in central Lima were infested with larvae of S. catenifer. Infested avocado fruit sold at this market could represent a potential incursion threat to coastal Hass avocado production regions in Perú that are reportedly free of this pest.

Morphometric variations of laelapine mite (Acari: Mesostigmata populations infesting small mammals (Mammalia in Brazil

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F. Martins-Hatano

Full Text Available The goal of this study was to evaluate the morphometric variation of laelapine populations (Acari, Mesostigmata associated with neotropical oryzomyine rodents at different geographic localities in Brazil. Three nominal mite species were selected for study, all infesting the pelage of small mammals at different localities in Rio de Janeiro, Espírito Santo, Bahia, and the Federal District, Brazil. To analyse morphometric characteristics, thirty-seven morphological characters distributed across the whole body of each specimen were measured. We use the Analysis of Principal Components, extracting the three first axes and projecting each mite in these axes. Major species level changes in the taxonomy of the host mammals allows an independent examination of morphometric variation of mites infesting a set of distinctly different host species at different geographic localities. Gigantolaelaps vitzthumi and Laelaps differens are associated with oryzomyine rodents of the genus Cerradomys, and consistently showed a tendency to cluster by host phylogeny. Laelaps manguinhosi associated with Nectomys rattus in central Brazil is morphometrically distinct from mites infesting N. squamipes in the coastal restingas of Rio de Janeiro and Espírito Santo. The results obtained here indicate that laelapine mite populations can vary among geographic areas and among phylogenetically related host species. Clearly, the study of these mites at the population level can be an important tool for clarifying the taxonomy of both mites and hosts.

Morphometric variations of laelapine mite (Acari: Mesostigmata) populations infesting small mammals (Mammalia) in Brazil.

Science.gov (United States)

Martins-Hatano, F; Gettinger, D; Manhães, M L; Bergallo, H G

2012-08-01

The goal of this study was to evaluate the morphometric variation of laelapine populations (Acari, Mesostigmata) associated with neotropical oryzomyine rodents at different geographic localities in Brazil. Three nominal mite species were selected for study, all infesting the pelage of small mammals at different localities in Rio de Janeiro, Espírito Santo, Bahia, and the Federal District, Brazil. To analyse morphometric characteristics, thirty-seven morphological characters distributed across the whole body of each specimen were measured. We use the Analysis of Principal Components, extracting the three first axes and projecting each mite in these axes. Major species level changes in the taxonomy of the host mammals allows an independent examination of morphometric variation of mites infesting a set of distinctly different host species at different geographic localities. Gigantolaelaps vitzthumi and Laelaps differens are associated with oryzomyine rodents of the genus Cerradomys, and consistently showed a tendency to cluster by host phylogeny. Laelaps manguinhosi associated with Nectomys rattus in central Brazil is morphometrically distinct from mites infesting N. squamipes in the coastal restingas of Rio de Janeiro and Espírito Santo. The results obtained here indicate that laelapine mite populations can vary among geographic areas and among phylogenetically related host species. Clearly, the study of these mites at the population level can be an important tool for clarifying the taxonomy of both mites and hosts.

Damage of Rhopalosiphum padi (L.) (Hemiptera: Aphididae) on wheat plants related to duration time and density of infestation

International Nuclear Information System (INIS)

Roza-Gomes, Margarida F.; Salvadori, Jose R.; Schons, Jurema

2008-01-01

Aphids are considered relevant pests on wheat either by direct damage through sap sucking or by indirect damage vectoring BYDV (Barley yellow dwarf virus). Rhopalosiphum padi L. has been observed infesting wheat fields with an increasing frequency. The knowledge and the available technology, besides being more related to other aphids species already recognized as pests, they are insufficient to control the specific c problem of R. padi. Thus, this work evaluated the effects of feeding duration and infestation densities of R. padi on seedlings of wheat cv. EMBRAPA 16. rain yield, yield components and the extent of symptoms were recorded. The experiment was carried out in the fi eld under a completely randomized split-plot experimental design with four replications. The main plot was feeding duration (two and seven days) and the sub-plots were infestation densities (zero, two and 10 aphids per plant). Independent on feeding duration, 10 aphids per plant resulted in significant yield losses, reduction of number of heads and tillers per plant. Canopy dry matter was also reduced. Infestations of two and 10 aphids per plant resulted in continuous yellowing of wheat plants from tillering to the end of flowering stage. When aphids fed for seven days on wheat, more yellowing symptoms were observed at the flower stage in comparison with two days feeding. (author)

Non-linear Growth Models in Mplus and SAS

Science.gov (United States)

Grimm, Kevin J.; Ram, Nilam

2013-01-01

Non-linear growth curves or growth curves that follow a specified non-linear function in time enable researchers to model complex developmental patterns with parameters that are easily interpretable. In this paper we describe how a variety of sigmoid curves can be fit using the Mplus structural modeling program and the non-linear mixed-effects modeling procedure NLMIXED in SAS. Using longitudinal achievement data collected as part of a study examining the effects of preschool instruction on academic gain we illustrate the procedures for fitting growth models of logistic, Gompertz, and Richards functions. Brief notes regarding the practical benefits, limitations, and choices faced in the fitting and estimation of such models are included. PMID:23882134

Modelling diameter growth, mortality and recruitment of trees in ...

African Journals Online (AJOL)

Modelling diameter growth, mortality and recruitment of trees in miombo woodlands of Tanzania. ... Individual tree diameter growth and mortality models, and area-based recruitment models were developed. ... AJOL African Journals Online.

Understanding cross-communication between aboveground and belowground tissues via transcriptome analysis of a sucking insect whitefly-infested pepper plants.

Science.gov (United States)

Park, Yong-Soon; Ryu, Choong-Min

2014-01-03

Plants have developed defensive machinery to protect themselves against herbivore and pathogen attacks. We previously reported that aboveground whitefly (Bemisia tabaci Genn.) infestation elicited induced resistance in leaves and roots and influenced the modification of the rhizosphere microflora. In this study, to obtain molecular evidence supporting these plant fitness strategies against whitefly infestation, we performed a 300 K pepper microarray analysis using leaf and root tissues of pepper (Capsicum annuum L.) applied with whitefly, benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH), and the combination of BTH+whitefly. We defined differentially expressed genes (DEGs) as genes exhibiting more than 2-fold change (1.0 based on log2 values) in expression in leaves and roots in response to each treatment compared to the control. We identified a total of 16,188 DEGs in leaves and roots. Of these, 6685, 6752, and 4045 DEGs from leaf tissue and 6768, 7705, and 7667 DEGs from root tissue were identified in the BTH, BTH+whitefly, and whitefly treatment groups, respectively. The total number of DEGs was approximately two-times higher in roots than in whitefly-infested leaves subjected to whitefly infestation. Among DEGs, whitefly feeding induced salicylic acid and jasmonic acid/ethylene-dependent signaling pathways in leaves and roots. Several transporters and auxin-responsive genes were upregulated in roots, which can explain why biomass increase is facilitated. Using transcriptome analysis, our study provides new insights into the molecular basis of whitefly-mediated intercommunication between aboveground and belowground plant tissues and provides molecular evidence that may explain the alteration of rhizosphere microflora and root biomass by whitefly infestation. Copyright © 2013 Elsevier Inc. All rights reserved.

Forest growth modeling in the Southern Region, National Forest System

International Nuclear Information System (INIS)

Belcher, D.M.

1988-01-01

This paper discusses an attempt to combine individual tree growth models and stand level growth models currently available for the Region into one computer program. Operation of the program is explained and growth models are included

Patterns of infestation by the trombiculid mite Eutrombicula alfreddugesi in four sympatric lizard species (genus Tropidurus) in northeastern Brazil.

Science.gov (United States)

Rocha, C F D; Cunha-Barros, M; Menezes, V A; Fontes, A f; Vrcibradic, D; Van Sluys, M

2008-06-01

We studied the parasitism by the chigger mite Eutrombicula alfreddugesi on four sympatric lizard species of the genus Tropidurus in Morro do Chapéu, Bahia state, Brazil: T. hispidus, T. cocorobensis, T. semitaeniatus and T. erythrocephalus. For each species, we investigated the patterns of infestation and analyzed to which extent they varied among the hosts. We calculated the spatial niche breadth of the chigger mite on the body of each host species and the distribution of mites along the hosts' bodies for each Tropidurus species. All four species of Tropidurus at Morro do Chapéu were parasited by the chigger mite, with high (97-100%) prevalences. Host body size significantly explained the intensity of mite infestation for all species, except T. erythrocephalus. The body regions with highest intensity of infestation in the four lizard species were the mite pockets. The spacial niche width of the chigger varied consistently among the four lizards species studied being highest for T. erytrocephalus and lowest for T. cocorobensis. We conclude that the distribution and intensity with which lizards of the genus Tropidurus are infested by Eutrombicula alfreddugesi larvae results from the interaction between aspects of host morphology (such as body size and the occurrence and distribution of mite pockets) and ecology (especially microhabitat use).

Patterns of infestation by the trombiculid mite Eutrombicula alfreddugesi in four sympatric lizard species (genus Tropidurus in northeastern Brazil

Directory of Open Access Journals (Sweden)

Rocha C.F.D.

2008-06-01

Full Text Available We studied the parasitism by the chigger mite Eutrombicula alfreddugesi on four sympatric lizard species of the genus Tropidurus in Morro do Chapéu, Bahia state, Brazil: T. hispidus, T. cocorobensis, T. semitaeniatus and T. erythrocephalus. For each species, we investigated the patterns of infestation and analyzed to which extent they varied among the hosts. We calculated the spatial niche breadth of the chigger mite on the body of each host species and the distribution of mites along the hosts’ bodies for each Tropidurus species. All four species of Tropidurus at Morro do Chapéu were parasited by the chigger mite, with high (97-100% prevalences. Host body size significantly explained the intensity of mite infestation for all species, except T. erythrocephalus. The body regions with highest intensity of infestation in the four lizard species were the mite pockets. The spacial niche width of the chigger varied consistently among the four lizards species studied being highest for T. erytrocephalus and lowest for T. cocorobensis. We conclude that the distribution and intensity with which lizards of the genus Tropidurus are infested by Eutrombicula alfreddugesi larvae results from the interaction between aspects of host morphology (such as body size and the occurrence and distribution of mite pockets and ecology (especially microhabitat use.

United States geological survey's reserve-growth models and their implementation

Science.gov (United States)

Klett, T.R.

2005-01-01

The USGS has developed several mathematical models to forecast reserve growth of fields both in the United States (U.S.) and the world. The models are based on historical reserve growth patterns of fields in the U.S. The patterns of past reserve growth are extrapolated to forecast future reserve growth. Changes of individual field sizes through time are extremely variable, therefore, the reserve growth models take on a statistical approach whereby volumetric changes for populations of fields are used in the models. Field age serves as a measure of the field-development effort that is applied to promote reserve growth. At the time of the USGS World Petroleum Assessment 2000, a reserve growth model for discovered fields of the world was not available. Reserve growth forecasts, therefore, were made based on a model of historical reserve growth of fields of the U.S. To test the feasibility of such an application, reserve growth forecasts were made of 186 giant oil fields of the world (excluding the U.S. and Canada). In addition, forecasts were made for these giant oil fields subdivided into those located in and outside of Organization of Petroleum Exporting Countries (OPEC). The model provided a reserve-growth forecast that closely matched the actual reserve growth that occurred from 1981 through 1996 for the 186 fields as a whole, as well as for both OPEC and non-OPEC subdivisions, despite the differences in reserves definition among the fields of the U.S. and the rest of the world. ?? 2005 International Association for Mathematical Geology.

Disinfestation of different varieties of potato naturally or artificially infested by the potato tuber moth, Phthorimea Operculella Zell. In the storage

International Nuclear Information System (INIS)

Haiba, M.I.

1994-01-01

The exposure of potato tuber varieties of Alpha, Spunta, Cara and escort to radiation dose level of 150 Gy could be used to disinfest the potatoes from their natural attacked pest, Phthorimaea Operculella, after the harvest and before storage. Escort variety exhibited somewhat resistance to the natural infestation if compared with the others. The irradiation of the potato tubers did not protect them from the re infestation, during the storage. Also, there were significant changes in some biological properties of the resulted pests, among the four potato varieties, whether the potatoes were non-irradiated or irradiated. The feeding of the artificial infested larvae on the treated tubers gave some malformed adults. 3 tabs

Attraction of Phytoseiulus persimilis (Acari: Phytoseiidae) towards volatiles from various Tetranychus urticae-infested plant species.

Science.gov (United States)

van den Boom, C E M; van Beek, T A; Dicke, M

2002-12-01

Plants infested with the spider mite Tetranychus urticae Koch, may indirectly defend themselves by releasing volatiles that attract the predatory mite Phytoseiulus persimilis Athias-Henriot. Several plants from different plant families that varied in the level of spider mite acceptance were tested in an olfactometer. The predatory mites were significantly attracted to the spider mite-infested leaves of all test plant species. No differences in attractiveness of the infested plant leaves were found for predatory mites reared on spider mites on the different test plants or on lima bean. Thus, experience with the spider mite-induced plant volatiles did not affect the predatory mites. Jasmonic acid was applied to ginkgo leaves to induce a mimic of a spider mite-induced volatile blend, because the spider mites did not survive when incubated on ginkgo. The volatile blend induced in ginkgo by jasmonic acid was slightly attractive to predatory mites. Plants with a high degree of direct defence were thought to invest less in indirect defence than plants with a low degree of direct defence. However, plants that had a strong direct defence such as ginkgo and sweet pepper, did emit induced volatiles that attracted the predatory mite. This indicates that a combination of direct and indirect defence is to some extent compatible in plant species.

A survey of ectoparasite infestations in stray dogs of Gwang-ju City, Republic of Korea.

Science.gov (United States)

Chee, Jeong Hyun; Kwon, Jung Kee; Cho, Ho Seong; Cho, Kyoung Oh; Lee, Yu Jin; Abd El-Aty, A M; Abdel-Aty, A M; Shin, Sung Shik

2008-03-01

This study was designed to investigate the incidence of ectoparasite infestation among stray dogs in Gwang-ju City, Republic of Korea. A total of 103 stray dogs collected in the Animal Shelter of Gwang-ju City from November 2003 to August 2005 were investigated in this study. Ectoparasites of one or more genera were detected in 45.6% (47 / 103) of the dogs examined for dermatologic lesions and/or skin scrapings (from 3-5 affected areas). Otodectes cynotis was found to be the most frequent parasite (22.3%, 23 / 103), followed by Sarcoptes scabiei var canis (19.4%, 20 / 103), Ctenocephalides canis (6.8%, 7 / 103), Demodex canis (4.9%, 5 / 103), and Trichodectes canis (1.0%, 1 / 103). Monospecific infestation was found in 83.0% (39 / 47) of the affected dogs, whereas concurrent infestations with 2 or more ectoparasites per animal were found in 17.0% (8 / 47) of the affected dogs. Trichodectes canis is reported for the first time in the Republic of Korea. Dogs less than 1 yr old were more heavily infected than other age groups (66.7%), and small-sized dogs of less than 3 kg body weight were more heavily infected than larger dogs (41.7%).

Field efficacy of eprinomectin against the sucking louse Haematopinus asini on naturally infested donkeys.

Science.gov (United States)

Veneziano, Vincenzo; Galietti, Alfredo; Mariani, Ugo; Di Loria, Antonio; Piantedosi, Diego; Neola, Benedetto; Guccione, Jacopo; Gokbulut, Cengiz

2013-08-01

A trial was conducted to assess the efficacy of eprinomectin (EPR) against the sucking louse Haematopinus asini on naturally infested donkeys. Parasitological investigations were performed on fifteen animals. On day 0, donkeys received EPR pour-on at the manufacturer's recommended cattle dose. Louse counts were performed on days -1, 7, 14, 21, 28, 35, 42, 49 and 56 at seven predilection sites on the skin of each donkey. EPR was completely effective (100%) from day 7, until the end of the study. Clinically no adverse reactions were observed in any of donkeys treated. EPR was considered to be 100% effective against H. asini. This is the first trial to evaluate the efficacy of EPR against a natural louse infestation in donkeys. Copyright © 2013 Elsevier Ltd. All rights reserved.

Environmental characteristics of the cemeteries of Buenos Aires City (Argentina and infestation levels of Aedes aegypti (Diptera: Culicidae

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Vezzani Darío

2001-01-01

Full Text Available Cemeteries with many water-filled containers, flowers, sources of human blood, and shade are favorable urban habitats for the proliferation of Aedes aegypti, a vector of yellow fever and dengue. A total of 22,956 containers was examined in the five cemeteries of the city of Buenos Aires, Argentina. The vector was found in four cemeteries that showed an average infestation level of 5.5% (617 positive out of 11,196 water-filled containers. The four cemeteries positive for Ae. aegypti showed significantly different (p<0.01 infestation levels. Vegetation cover and percentage of infestation were significantly correlated (p<0.01, but neither cemetery area nor number of available containers were significantly related to the proportion of positive vases. Our results suggest that the cemeteries of Buenos Aires represent a gradient of habitat favorableness for this vector species, some of which may act as foci for its proliferation and dispersal.

Mistletoe (Viscum album) infestation in the Scots pine stimulates drought-dependent oxidative damage in summer.

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Mutlu, Salih; Ilhan, Veli; Turkoglu, Halil Ibrahim

2016-04-01

This study sought to contribute to the understanding of the detrimental effect of the mistletoe (Viscum albumL.), a hemiparasitic plant, on the mortality of the Scots pine (Pinus sylvestrisL.). Fieldwork was conducted in the town of Kelkit (Gumushane province, Turkey) from April to October in 2013. Pine needles of similar ages were removed from the branches of mistletoe-infested and noninfested Scots pine plants, then transported to the laboratory and used as research materials. The effects of the mistletoe on the Scots pine during infestation were evaluated by determining the levels of water, electrolyte leakage (EL), malondialdehyde (MDA, being a product of lipid peroxidation) and reactive oxygen species (ROS) such as superoxide anion (O2 (-•)), hydrogen peroxide (H2O2) and hydroxyl radical ((•)OH). In addition, the activities of antioxidative enzymes such as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX) were measured in the same samples. The highest level of drought stress was found in summer (especially in August) as a result of the lowest water content in the soil and the highest average temperature occurring in these months. The drought stress induced by mistletoe infestation caused a regular decrease in water content, while it increased the levels of EL, MDA and ROS (H2O2, O2 (-•)and(•)OH). The infestation also stimulated the activities of CAT and POX, with the exception of SOD. On the other hand, in August, when the drought conditions were the harshest, the levels of EL and MDA, which are two of the most important indicator parameters for oxidative stress, as well as the levels of H2O2and(•)OH, which are two of the ROS leading to oxidative stress, reached the highest values in both infested and noninfested needles, whereas the O2 (-•)level decreased. For the same period and needles, CAT activity increased, while SOD activity decreased. Peroxidase activity, however, did not exhibit a significant change. Our findings indicate

Do Aphids Alter Leaf Surface Temperature Patterns During Early Infestation?

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Thomas Cahon

2018-03-01

Full Text Available Arthropods at the surface of plants live in particular microclimatic conditions that can differ from atmospheric conditions. The temperature of plant leaves can deviate from air temperature, and leaf temperature influences the eco-physiology of small insects. The activity of insects feeding on leaf tissues, may, however, induce changes in leaf surface temperatures, but this effect was only rarely demonstrated. Using thermography analysis of leaf surfaces under controlled environmental conditions, we quantified the impact of presence of apple green aphids on the temperature distribution of apple leaves during early infestation. Aphids induced a slight change in leaf surface temperature patterns after only three days of infestation, mostly due to the effect of aphids on the maximal temperature that can be found at the leaf surface. Aphids may induce stomatal closure, leading to a lower transpiration rate. This effect was local since aphids modified the configuration of the temperature distribution over leaf surfaces. Aphids were positioned at temperatures near the maximal leaf surface temperatures, thus potentially experiencing the thermal changes. The feedback effect of feeding activity by insects on their host plant can be important and should be quantified to better predict the response of phytophagous insects to environmental changes.

In silico modeling for tumor growth visualization.

Science.gov (United States)

Jeanquartier, Fleur; Jean-Quartier, Claire; Cemernek, David; Holzinger, Andreas

2016-08-08

Cancer is a complex disease. Fundamental cellular based studies as well as modeling provides insight into cancer biology and strategies to treatment of the disease. In silico models complement in vivo models. Research on tumor growth involves a plethora of models each emphasizing isolated aspects of benign and malignant neoplasms. Biologists and clinical scientists are often overwhelmed by the mathematical background knowledge necessary to grasp and to apply a model to their own research. We aim to provide a comprehensive and expandable simulation tool to visualizing tumor growth. This novel Web-based application offers the advantage of a user-friendly graphical interface with several manipulable input variables to correlate different aspects of tumor growth. By refining model parameters we highlight the significance of heterogeneous intercellular interactions on tumor progression. Within this paper we present the implementation of the Cellular Potts Model graphically presented through Cytoscape.js within a Web application. The tool is available under the MIT license at https://github.com/davcem/cpm-cytoscape and http://styx.cgv.tugraz.at:8080/cpm-cytoscape/ . In-silico methods overcome the lack of wet experimental possibilities and as dry method succeed in terms of reduction, refinement and replacement of animal experimentation, also known as the 3R principles. Our visualization approach to simulation allows for more flexible usage and easy extension to facilitate understanding and gain novel insight. We believe that biomedical research in general and research on tumor growth in particular will benefit from the systems biology perspective.

Bridging process-based and empirical approaches to modeling tree growth

Science.gov (United States)

Harry T. Valentine; Annikki Makela; Annikki Makela

2005-01-01

The gulf between process-based and empirical approaches to modeling tree growth may be bridged, in part, by the use of a common model. To this end, we have formulated a process-based model of tree growth that can be fitted and applied in an empirical mode. The growth model is grounded in pipe model theory and an optimal control model of crown development. Together, the...

Regression models for linking patterns of growth to a later outcome: infant growth and childhood overweight

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Andrew K. Wills

2016-04-01

Full Text Available Abstract Background Regression models are widely used to link serial measures of anthropometric size or changes in size to a later outcome. Different parameterisations of these models enable one to target different questions about the effect of growth, however, their interpretation can be challenging. Our objective was to formulate and classify several sets of parameterisations by their underlying growth pattern contrast, and to discuss their utility using an expository example. Methods We describe and classify five sets of model parameterisations in accordance with their underlying growth pattern contrast (conditional growth; being bigger v being smaller; becoming bigger and staying bigger; growing faster v being bigger; becoming and staying bigger versus being bigger. The contrasts are estimated by including different sets of repeated measures of size and changes in size in a regression model. We illustrate these models in the setting of linking infant growth (measured on 6 occasions: birth, 6 weeks, 3, 6, 12 and 24 months in weight-for-height-for-age z-scores to later childhood overweight at 8y using complete cases from the Norwegian Childhood Growth study (n = 900. Results In our expository example, conditional growth during all periods, becoming bigger in any interval and staying bigger through infancy, and being bigger from birth were all associated with higher odds of later overweight. The highest odds of later overweight occurred for individuals who experienced high conditional growth or became bigger in the 3 to 6 month period and stayed bigger, and those who were bigger from birth to 24 months. Comparisons between periods and between growth patterns require large sample sizes and need to consider how to scale associations to make comparisons fair; with respect to the latter, we show one approach. Conclusion Studies interested in detrimental growth patterns may gain extra insight from reporting several sets of growth pattern

Infestation and distribution of the mite Varroa destructor in colonies of africanized bees

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G. Moretto

Full Text Available Whereas in several parts of the world varroa is the major pest affecting apiculture, in others the parasite is unknown to many beekeepers because its damage to bees is minor. The impact of the mite Varroa destructor is related to the climatic conditions and the races of Apis mellifera bees in each region where the pest exists. In the present study, the current level of infestation by the mite was assessed to determine the evolution of the pest in Africanized bee colonies in Southern Brazil. This level of infestation was considered low: approximately two mites per one hundred adult bees. This result is similar to that obtained for the same apiary almost five years ago and for others distributed in various regions of Brazil. In the present study, we also estimated the total varroa population and its distribution among brood and adults in each bee colony.

Growth of cortical neuronal network in vitro: Modeling and analysis

International Nuclear Information System (INIS)

Lai, P.-Y.; Jia, L. C.; Chan, C. K.

2006-01-01

We present a detailed analysis and theoretical growth models to account for recent experimental data on the growth of cortical neuronal networks in vitro [Phys. Rev. Lett. 93, 088101 (2004)]. The experimentally observed synchronized firing frequency of a well-connected neuronal network is shown to be proportional to the mean network connectivity. The growth of the network is consistent with the model of an early enhanced growth of connection, but followed by a retarded growth once the synchronized cluster is formed. Microscopic models with dominant excluded volume interactions are consistent with the observed exponential decay of the mean connection probability as a function of the mean network connectivity. The biological implications of the growth model are also discussed

Thermal time model for Egyptian broomrape ‎‎(Phelipanche aegyptiaca parasitism dynamics in carrot ‎‎(Daucus carota L.: Field validation ‎

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Amnon Cochavi

2016-12-01

Full Text Available Carrot, a highly profitable crop in Israel, is severely damaged by Phelipanche aegyptiaca ‎parasitism. Herbicides can effectively control the parasite and prevent damage, but for ‎optimal results, knowledge about the soil-subsurface phenological stage of the parasite is ‎essential. Parasitism dynamics models have been successfully developed for the parasites P. ‎aegyptiaca, Orobanche cumana and O. minor in the summer crops, tomato, sunflower and ‎red clover, respectively. However, these models, which are based on a linear relationship ‎between thermal time and the parasitism dynamics, may not necessarily be directly ‎applicable to the P. aegyptiaca-carrot system. The objective of the current study was to ‎develop a thermal time model to predict the effect of P. aegyptiaca parasitism dynamics on ‎carrot growth. For development and validation of the models, data was collected from a ‎temperature-controlled growth experiment and from 13 plots naturally infested with P. ‎aegyptiaca in commercial carrot fields. Our results revealed that P. aegyptiaca development ‎is related to soil temperature. Moreover, unlike P. aegyptiaca parasitism in sunflower and ‎tomato, which could be predicted both a linear model, P. aegyptiaca parasitism dynamics ‎on carrot roots required a nonlinear model, due to the wider range of growth temperatures of ‎both the carrot and the parasite. Hence, two different nonlinear models were developed for ‎optimizing the prediction of P. aegyptiaca parasitism dynamics. Both models, a beta ‎function model and combined model composed of a beta function and a sigmoid curve, were ‎able to predict first P. aegyptiaca attachment. However, overall P. aegyptiaca dynamics was ‎described more accurately by the combined model (RMSE =14.58 and 10.79, respectively. ‎The results of this study will complement previous studies on P. aegyptiaca management by ‎herbicides to facilitate optimal carrot growth and

Balanced growth path solutions of a Boltzmann mean field game model for knowledge growth

KAUST Repository

Burger, Martin

2016-11-18

In this paper we study balanced growth path solutions of a Boltzmann mean field game model proposed by Lucas and Moll [15] to model knowledge growth in an economy. Agents can either increase their knowledge level by exchanging ideas in learning events or by producing goods with the knowledge they already have. The existence of balanced growth path solutions implies exponential growth of the overall production in time. We prove existence of balanced growth path solutions if the initial distribution of individuals with respect to their knowledge level satisfies a Pareto-tail condition. Furthermore we give first insights into the existence of such solutions if in addition to production and knowledge exchange the knowledge level evolves by geometric Brownian motion.

Modeling the effects of ozone on soybean growth and yield.

Science.gov (United States)

Kobayashi, K; Miller, J E; Flagler, R B; Heck, W W

1990-01-01

A simple mechanistic model was developed based on an existing growth model in order to address the mechanisms of the effects of ozone on growth and yield of soybean [Glycine max. (L.) Merr. 'Davis'] and interacting effects of other environmental stresses. The model simulates daily growth of soybean plants using environmental data including shortwave radiation, temperature, precipitation, irrigation and ozone concentration. Leaf growth, dry matter accumulation, water budget, nitrogen input and seed growth linked to senescence and abscission of leaves are described in the model. The effects of ozone are modeled as reduced photosynthate production and accelerated senescence. The model was applied to the open-top chamber experiments in which soybean plants were exposed to ozone under two levels of soil moisture regimes. After calibrating the model to the growth data and seed yield, goodness-of-fit of the model was tested. The model fitted well for top dry weight in the vegetative growth phase and also at maturity. The effect of ozone on seen yield was also described satisfactorily by the model. The simulation showed apparent interaction between the effect of ozone and soil moisture stress on the seed yield. The model revealed that further work is needed concerning the effect of ozone on the senescence process and the consequences of alteration of canopy microclimate by the open-top chambers.

Gamma irradiation followed by cold storage as a quarantine treatment for Florida grapefruit infested with Caribbean fruit fly

International Nuclear Information System (INIS)

Von Windeguth, D.L.; Gould, W.P.

1990-01-01

'Marsh' white grapefruit, Citrus paradisi (Macf.). infested with eggs and larvae of Caribbean fruit fly, Anastrepha suspensa (Loew) were subjected to ionizing radiation at several low doses followed by cold (1.1°C) storage for 0 to 8 days. Data analyses indicated that an irradiation dose of 50 Gray followed by 5 days of cold storage will give in excess of probit 9 level of quarantine security. A test involving more than 100,000 insects infesting grapefruit confirmed the efficacy of this treatment

Plant Growth Modeling Using L-System Approach and Its Visualization

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Atris Suyantohadi

2011-05-01

Full Text Available The visualizationof plant growth modeling using computer simulation has rarely been conducted with Lindenmayer System (L-System approach. L-System generally has been used as framework for improving and designing realistic modeling on plant growth. It is one kind of tools for representing plant growth based on grammar sintax and mathematic formulation. This research aimed to design modeling and visualizing plant growth structure generated using L-System. The environment on modeling design used three dimension graphic on standart OpenGL format. The visualization on system design has been developed by some of L-System grammar, and the output graphic on three dimension reflected on plant growth as a virtual plant growth system. Using some of samples on grammar L-System rules for describing of the charaterictics of plant growth, the visualization of structure on plant growth has been resulted and demonstrated.

Sensitivity of Different Cattle Breeds to the Infestation of Cattle Ticks Amblyomma variegatum, Rhipicephalus microplus, and Hyalomma spp. on the Natural Pastures of Opkara Farm, Benin

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Roland Eric Yessinou

2018-01-01

Full Text Available A study was carried out on the Opkara (Benin cattle farm on 64 cattle of four different breeds (16 individuals per breed from June to December 2016. During this study, three tick species were found in different numbers, Amblyomma variegatum (732, Rhipicephalus microplus (8079, and Hyalomma spp. (208, with parasitic intensity of 11.90, 126.23, and 3.25, respectively. The interracial comparison of the tick infestation between the cattle showed a significant difference (P<0.001. However, Girolando was more infested than all the cattle breeds. Infestation of A. variegatum, R. microplus, and Hyalomma spp. on the Girolando was, respectively, 19.43 ± 2.71, 171.25 ± 23.50, and 7.12 ± 0.63, but the Borgou were less infested. Borgou breed females were more infested by A. variegatum (4.41 ± 1.14 than females Girolando (4.20 ± 0.90. The Crossbred and Azawak females were less infested (P<0.01. The mean of A. variegatum on Borgou, Azawak, Crossbred, and Girolando calves was 1.29 ± 0.35, 0.66 ± 0.26, 1.37 ± 0.37, and 2.25 ± 0.48 (P<0.01, respectively. The results of this study can be exploited to include genetic and nongenetic approaches to tick control.

Africanized honey bees (Apis mellifera L. are more efficient at removing worker brood artificially infested with the parasitic mite Varroa jacobsoni Oudemans than are Italian bees or Italian/Africanized hybrids

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Guerra Jr. José Carlos Vieira

2000-01-01

Full Text Available Africanized honey bees are more tolerant of infestations with the mite Varroa jacobsoni than are honey bees of European origin. The capacity of these bees to detect and react to brood infested with this mite could be one of the factors determining this tolerance. We tested colonies of Africanized bees headed by queens from swarms collected in Ribeirão Preto, São Paulo State. The Italian colonies had queens imported directly from the USA, or from the Brazilian Island of Fernando de Noronha, where varroa-infested Italian colonies have been maintained, untreated, since 1984. Recently sealed worker brood cells were artificially infested by opening the cell capping, inserting live adult female mites and resealing the cells. Control cells were treated in the same way, but without introducing mites. The ability of the Africanized honey bees to recognize and remove this artificially infested brood was compared with that of first generation Italian/Africanized hybrid bees, and with the two groups of "pure" Italian bees, in three separate experiments. Africanized colonies removed a mean of 51% of the infested brood, while Italian/Africanized hybrid colonies removed 25%. Africanized colonies also removed a significantly greater proportion of infested brood than did Italian colonies, headed by queens from the USA (59 vs. 31%, respectively. Similarly, when Africanized colonies were compared with colonies of Italian bees from Fernando de Noronha, the former were found to be significantly more efficient at removing infested brood (61 vs. 35%, respectively, even though the population of Italian bees on this island has been exposed to and survived varroa infestations (without treatment for more than 12 years. Only the Africanized honey bees removed a significant proportion of varroa-infested brood, when the data was corrected for brood removal from control cells.

The Efficacy of Emamectin Benzoate against Infestations of Lepeophtheirus salmonis on Farmed Atlantic Salmon (Salmo salar L) in Scotland, 2002–2006

Science.gov (United States)

Lees, Fiona; Baillie, Mark; Gettinby, George; Revie, Crawford W.

2008-01-01

Background Infestations of the parasitic copepod Lepeophtheirus salmonis, commonly referred to as sea lice, represent a major challenge to commercial salmon aquaculture. Dependence on a limited number of theraputants to control such infestations has led to concerns of reduced sensitivity in some sea lice populations. This study investigates trends in the efficacy of the in-feed treatment emamectin benzoate in Scotland, the active ingredient most widely used across all salmon producing regions. Methodology/Principal Findings Study data were drawn from over 50 commercial Atlantic salmon farms on the west coast of Scotland between 2002 and 2006. An epi-informatics approach was adopted whereby available farm records, descriptive epidemiological summaries and statistical linear modelling methods were used to identify factors that significantly affect sea lice abundance following treatment with emamectin benzoate (SLICE®, Schering Plough Animal Health). The results show that although sea lice infestations are reduced following the application of emamectin benzoate, not all treatments are effective. Specifically there is evidence of variation across geographical regions and a reduction in efficacy over time. Conclusions/Significance Reduced sensitivity and potential resistance to currently available medicines are constant threats to maintaining control of sea lice populations on Atlantic salmon farms. There is a need for on-going monitoring of emamectin benzoate treatment efficacy together with reasons for any apparent reduction in performance. In addition, strategic rotation of medicines should be encouraged and empirical evidence for the benefit of such strategies more fully evaluated. PMID:18253496

Non-rigid image registration using bone growth model

DEFF Research Database (Denmark)

Bro-Nielsen, Morten; Gramkow, Claus; Kreiborg, Sven

1997-01-01

Non-rigid registration has traditionally used physical models like elasticity and fluids. These models are very seldom valid models of the difference between the registered images. This paper presents a non-rigid registration algorithm, which uses a model of bone growth as a model of the change...... between time sequence images of the human mandible. By being able to register the images, this paper at the same time contributes to the validation of the growth model, which is based on the currently available medical theories and knowledge...

Detection of Cocoa Pod Borer Infestation Using Sex Pheromone Trap and its Control by Pod Wrapping

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Dian Rahmawati

2017-07-01

Full Text Available Cocoa pod borer (CPB, Conopomorpha cramerella Snellen (Lepidoptera: Gracillariidae is a major pest of cocoa. Detection of the pest infestation using sex pheromone traps in the early growth and development of cocoa pods is important for an early warning system programme. In order to prevent the pest infestation the young pods were wrapped with plastic bags. A research to study the CPB incidence was conducted at cocoa plantations in Banjarharjo and Banjaroya villages, District of Kalibawang; Hargotirto and Hargowilis villages, District of Kokap; and Pagerharjo village, District of Samigaluh, Yogyakarta. The experiments design used RCBD with four treatments (sex pheromone trap, combination of sex pheromone trap and pod wrapping, pod wrapping, and control and five replications. As many as 6 units/ha pheromone traps were installed with a distance of 40 m in between. Results showed that one month prior to the trap installation in the experimental plots there were ripen cocoa pods as many as 9-13%, which were mostly infested by CPB. During the time period of introducting research on August to Desember 2016 there was not rambutan fruits as the CPB host, hence the CPB resource was from infested cocoa pods. The CPB moth trapped as many as 0−7 (1.13 ± 0.14 moths/6 traps/12 observations. The seed damage due to CPB larvae in the pheromone trap treatments (23.98% was relatively similar with the control (20.25%. Seed damage rate in combination treatment of pheromone trap and pod wrapping (0.59% was relatively the same with the pod wrapping (0.20%. The pheromone trap was more usefull for monitoring tool rather than for control, meanwhile pod wrapping was an effective control measure of CPB.   Intisari Penggerek Buah Kakao (PBK, Conopomorpha cramerella Snellen (Lepidoptera: Gracillariidae merupakan salah satu hama utama kakao. Deteksi serangan hama PBK dengan perangkap feromon seks pada awal pertumbuhan dan perkembangan buah kakao penting dilakukan sebagai

Analysis of Unmanned Aerial System-Based CIR Images in Forestry—A New Perspective to Monitor Pest Infestation Levels

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Jan Rudolf Karl Lehmann

2015-03-01

Full Text Available The detection of pest infestation is an important aspect of forest management. In the case of the oak splendour beetle (Agrilus biguttatus infestation, the affected oaks (Quercus sp. show high levels of defoliation and altered canopy reflection signature. These critical features can be identified in high-resolution colour infrared (CIR images of the tree crown and branches level captured by Unmanned Aerial Systems (UAS. In this study, we used a small UAS equipped with a compact digital camera which has been calibrated and modified to record not only the visual but also the near infrared reflection (NIR of possibly infested oaks. The flight campaigns were realized in August 2013, covering two study sites which are located in a rural area in western Germany. Both locations represent small-scale, privately managed commercial forests in which oaks are economically valuable species. Our workflow includes the CIR/NIR image acquisition, mosaicking, georeferencing and pixel-based image enhancement followed by object-based image classification techniques. A modified Normalized Difference Vegetation Index (NDVImod derived classification was used to distinguish between five vegetation health classes, i.e., infested, healthy or dead branches, other vegetation and canopy gaps. We achieved an overall Kappa Index of Agreement (KIA   of 0.81 and 0.77 for each study site, respectively. This approach offers a low-cost alternative to private forest owners who pursue a sustainable management strategy.

Uncovering iron regulation with species-specific transcriptome patterns in Atlantic and coho salmon during a Caligus rogercresseyi infestation.

Science.gov (United States)

Valenzuela-Muñoz, V; Boltaña, S; Gallardo-Escárate, C

2017-09-01

Salmon species cultured in Chile evidence different levels of susceptibility to the sea louse Caligus rogercresseyi. These differences have mainly been associated with specific immune responses. Moreover, iron regulation seems to be an important mechanism to confer immunity during the host infestation. This response called nutritional immunity has been described in bacterial infections, despite that no comprehensive studies involving in marine ectoparasites infestation have been reported. With this aim, we analysed the transcriptome profiles of Atlantic and coho salmon infected with C. rogercresseyi to evidence modulation of the iron metabolism as a proxy of nutritional immune responses. Whole transcriptome sequencing was performed in samples of skin and head kidney from Atlantic and coho salmon infected with sea lice. RNA-seq analyses revealed significant upregulation of transcripts in both salmon species at 7 and 14 dpi in skin and head kidney, respectively. However, iron regulation transcripts were differentially modulated, evidencing species-specific expression profiles. Genes related to heme degradation and iron transport such as hepcidin, transferrin and haptoglobin were primary upregulated in Atlantic salmon; meanwhile, in coho salmon, genes associated with heme biosynthesis were strongly transcribed. In summary, Atlantic salmon, which are more susceptible to infestation, presented molecular mechanisms to deplete cellular iron availability, suggesting putative mechanisms of nutritional immunity. In contrast, resistant coho salmon were less affected by sea lice, mainly activating pro-inflammatory mechanisms to cope with infestation. © 2017 John Wiley & Sons Ltd.

Impacts of removing Chinese privet from riparian forests on plant communities and tree growth five years later

Science.gov (United States)

Jacob R. Hudson; James L. Hanula; Scott Horn

2014-01-01

An invasive shrub, Chinese privet (Ligustrum sinense Lour.), was removed from heavily infested riparian forests in the Georgia Piedmont in 2005 by mulching machine or chainsaw felling. Subsequent herbicide treatment eliminated almost all privet by 2007. Recovery of plant communities, return of Chinese privet, and canopy tree growth were measured on...

A mathematical model of microalgae growth in cylindrical photobioreactor

Science.gov (United States)

Bakeri, Noorhadila Mohd; Jamaian, Siti Suhana

2017-08-01

Microalgae are unicellular organisms, which exist individually or in chains or groups but can be utilized in many applications. Researchers have done various efforts in order to increase the growth rate of microalgae. Microalgae have a potential as an effective tool for wastewater treatment, besides as a replacement for natural fuel such as coal and biodiesel. The growth of microalgae can be estimated by using Geider model, which this model is based on photosynthesis irradiance curve (PI-curve) and focused on flat panel photobioreactor. Therefore, in this study a mathematical model for microalgae growth in cylindrical photobioreactor is proposed based on the Geider model. The light irradiance is the crucial part that affects the growth rate of microalgae. The absorbed photon flux will be determined by calculating the average light irradiance in a cylindrical system illuminated by unidirectional parallel flux and considering the cylinder as a collection of differential parallelepipeds. Results from this study showed that the specific growth rate of microalgae increases until the constant level is achieved. Therefore, the proposed mathematical model can be used to estimate the rate of microalgae growth in cylindrical photobioreactor.

Eprinomectin 1% Inyectable in control of Dermatobia hominis in naturally infested cattle

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Cristiano Grisi do Nascimento

2015-12-01

Full Text Available ABSTRACT. Nascimento C.G., Correia T.R., Oliveira G.F., Coumendouros K., Moraes P.A., Calado S.B., Bragaglia G.N., Rosa S.C., Toma S.B. & Scott F.B. [Eprinomectin 1% Inyectable in control of Dermatobia hominis in naturally infested cattle.] Eprinomectina 1%Injetável no controle de Dermatobia hominis em bovinos naturalmente infestados. Revista Brasileira de Medicina Veterinária, 37(Supl.1:81-84, 2015. Programa de Pós-Graduação em Ciências Tecnologia e Inovação em Agropecuária, Universidade Federal Rural do Rio de Janeiro, Campus Seropédica, Ecologia, BR 465 Km 7, Seropédica, RJ 23897-970, Brasil. E-mail: scott.fabio@gmail.com The aim of the study was to evaluate the effectiveness of injectable eprinomectin 1% on the control of Dermatobia hominis in naturally infested cattle. We selected 20 calves, crossbred Gir and Holstein breed, male and female, separated into two groups, control and treated. The control group of animals received no treatment, while the animals of the treated group received eprinomectin formulation of 1% at a single dose of 1 mL/50 kg body weight (200mcg of eprinomectin/kg per injectable route. On days +7 and +14 a count of the total number of live larvae of D. hominis on both sides of the animal for the purpose of evaluation of the effectiveness was performed. Statistical analysis of average living larvae of D. hominis counted among the groups, control and treated, showed that there was a significant difference (p ≤ 0.05 between groups on days +7 and +14. The investigational product showed an efficacy of 100% results in both experimental days. The injectable eprinomectin 1%, shown to be effective in cattle naturally infested by D. hominis (the human bot fly.

Localisation in a Growth Model with Interaction

Science.gov (United States)

Costa, M.; Menshikov, M.; Shcherbakov, V.; Vachkovskaia, M.

2018-05-01

This paper concerns the long term behaviour of a growth model describing a random sequential allocation of particles on a finite cycle graph. The model can be regarded as a reinforced urn model with graph-based interaction. It is motivated by cooperative sequential adsorption, where adsorption rates at a site depend on the configuration of existing particles in the neighbourhood of that site. Our main result is that, with probability one, the growth process will eventually localise either at a single site, or at a pair of neighbouring sites.

Molecular identification of hard ticks (Ixodes sp.) infesting rodents in Selangor, Malaysia

Science.gov (United States)

Ishak, Siti Nabilah; Shiang, Lim Fang; Taib, Farah Shafawati Mohd; Jing, Khoo Jing; Nor, Shukor Md; Yusof, Muhammad Afif; Sah, Shahrul Anuar Mohd; Sitam, Frankie Thomas; Japning, Jeffrine Rovie Ryan

2018-04-01

This study aims to identify hard ticks (Ixodes sp.) infesting rodents in three different sites in Selangor, Malaysia using a molecular approach. A total of 11 individual ticks infesting four different host species (Rattus tiomanicus, Rattus ratus, Maxomys surifer and Sundamys muelleri) were examined based on its morphological features, followed by molecular identification using mitochondrial 16S rDNA gene. Confirmation of the species identity was accomplished by using BLAST program. Clustering analysis based on 16S rDNA sequences was carried out by constructing Neighbour-joining (NJ) and Maximum parsimony (MP) tree using MEGA 7 to clarify the genetic identity of Ixodes sp. Based on morphological features, all individual ticks were only able to be identified up to genus level as most of the samples were fully engorged, damaged and lacked morphological characters. However, molecular analysis of samples revealed 99% similarity with Ixodes granulatus from the GenBank database. Thus, the result of this study showed that all these ticks (Ixodes granulatus) were genetically affiliated to a monophyletic group with highly homogenous sequences.

Ticks infesting amphibians and reptiles in Pernambuco, Northeastern Brazil.

Science.gov (United States)

Dantas-Torres, Filipe; Oliveira-Filho, Edmilson F; Soares, Fábio Angelo M; Souza, Bruno O F; Valença, Raul Baltazar P; Sá, Fabrício B

2008-01-01

Ticks infesting amphibians and reptiles in the State of Pernambuco are reviewed, based on the current literature and new collections recently carried out by the authors. To date, three tick species have been found on amphibians and reptiles in Pernambuco. Amblyomma fuscum appears to be exclusively associated with Boa constrictor, its type host. Amblyomma rotundatum has a relatively low host-specificity, being found on toads, snakes, and iguana. Amblyomma dissimile has been found on a lizard and also small mammals (i.e., rodents and marsupials). New tick-host associations and locality records are given.

Efficacy of fluralaner against Otodectes cynotis infestations in dogs and cats.

Science.gov (United States)

Taenzler, Janina; de Vos, Christa; Roepke, Rainer K A; Frénais, Régis; Heckeroth, Anja R

2017-01-16

The efficacy of fluralaner for the treatment of Otodectes cynotis infestations in dogs and cats was evaluated after oral (dogs) or topical administration (dogs and cats). Twenty-four dogs and sixteen cats were experimentally infested with O. cynotis and randomly allocated to equal sized groups (n = 8/group). Dog groups were treated once, either orally with fluralaner at a minimum dose of 25 mg/kg body weight, topically with fluralaner at a dose of 25 mg/kg body weight or topically with saline solution (control). Cat groups were treated once, either topically with fluralaner at a dose of 40 mg/kg body weight or topically with saline solution. Ears of all animals were examined otoscopically for live visible mites and the amount of debris and cerumen before, and 14 and 28 days after treatment. Twenty-eight days after treatment, animals were sedated and both ears were flushed to obtain the total number of live mites per animal. The efficacy was calculated, based on the results of the ear flushing, by comparing mean live mite counts in the fluralaner treated groups versus the saline solution treated group. A single topical treatment of cats with fluralaner reduced the mean mite counts by 100% (P dogs with fluralaner reduced the mean mite counts by 99.8% (P Cats treated topically with fluralaner had no mites visible during otoscopic examination at either 14 or 28 days after treatment. All dogs treated orally or topically with fluralaner had no mites visible during otoscopic examination at 28 days after treatment. At 14 days after treatment, only 1-2 mites were visible in three dogs (oral treatment: 2 dogs, topical treatment: 1 dog). All fluralaner-treated animals showed improvement in the amount of cerumen exudation compared with observations performed before treatment. No treatment related adverse events were observed in any dogs or cats enrolled in these studies. In this study, fluralaner administered topically to cats and orally or topically to dogs was

[Infestation by triatomines in rural settlement and resettlement areas the Region of Pontal do Paranapanema, State of São Paulo].

Science.gov (United States)

da Silva, Rubens Antonio; Sampaio, Susy Mary Perpétuo; Koyanagui, Paulo Hiroshi; Poloni, Marisa; de Carvalho, Maria Esther; Rodrigues, Vera Lúcia Cortiço Corrêa

2007-01-01

This study had the aim of assessing the characteristics of triatomine infestation in human dwellings in rural settlement and resettlement areas with regard to the time when infestation began. We analyzed data relating to 48 triatomine surveys carried out in 105 settlement areas and six resettlement areas in the region of Pontal do Paranapanema between January 1984 and June 2005. Among the 16 surveys in settlement areas, seven (43.8%) had positive findings, all of them in communities established eight or more years previously. Among the 32 surveys in resettlement areas, 23 (71.9%) had positive findings, all of them in communities established for periods shorter than eight years. Since the inhabitants of such communities frequently move, the need for constant vigilance to detect any cases of infestation by vector triatomines in new settlements cannot be overemphasized.

Growth rate in the dynamical dark energy models

International Nuclear Information System (INIS)

Avsajanishvili, Olga; Arkhipova, Natalia A.; Samushia, Lado; Kahniashvili, Tina

2014-01-01

Dark energy models with a slowly rolling cosmological scalar field provide a popular alternative to the standard, time-independent cosmological constant model. We study the simultaneous evolution of background expansion and growth in the scalar field model with the Ratra-Peebles self-interaction potential. We use recent measurements of the linear growth rate and the baryon acoustic oscillation peak positions to constrain the model parameter α that describes the steepness of the scalar field potential. (orig.)

Growth rate in the dynamical dark energy models.

Science.gov (United States)

Avsajanishvili, Olga; Arkhipova, Natalia A; Samushia, Lado; Kahniashvili, Tina

Dark energy models with a slowly rolling cosmological scalar field provide a popular alternative to the standard, time-independent cosmological constant model. We study the simultaneous evolution of background expansion and growth in the scalar field model with the Ratra-Peebles self-interaction potential. We use recent measurements of the linear growth rate and the baryon acoustic oscillation peak positions to constrain the model parameter [Formula: see text] that describes the steepness of the scalar field potential.

Investigation of Mediational Processes Using Parallel Process Latent Growth Curve Modeling

Science.gov (United States)

Cheong, JeeWon; MacKinnon, David P.; Khoo, Siek Toon

2010-01-01

This study investigated a method to evaluate mediational processes using latent growth curve modeling. The mediator and the outcome measured across multiple time points were viewed as 2 separate parallel processes. The mediational process was defined as the independent variable influencing the growth of the mediator, which, in turn, affected the growth of the outcome. To illustrate modeling procedures, empirical data from a longitudinal drug prevention program, Adolescents Training and Learning to Avoid Steroids, were used. The program effects on the growth of the mediator and the growth of the outcome were examined first in a 2-group structural equation model. The mediational process was then modeled and tested in a parallel process latent growth curve model by relating the prevention program condition, the growth rate factor of the mediator, and the growth rate factor of the outcome. PMID:20157639

Studying historical occupational careers with multilevel growth models

Directory of Open Access Journals (Sweden)

Wiebke Schulz

2010-10-01

Full Text Available In this article we propose to study occupational careers with historical data by using multilevel growth models. Historical career data are often characterized by a lack of information on the timing of occupational changes and by different numbers of observations of occupations per individual. Growth models can handle these specificities, whereas standard methods, such as event history analyses can't. We illustrate the use of growth models by studying career success of men and women, using data from the Historical Sample of the Netherlands. The results show that the method is applicable to male careers, but causes trouble when analyzing female careers.

Tax Evasion in a Model of Endogenous Growth

OpenAIRE

Been-Lon Chen

2003-01-01

This paper integrates tax evasion into a standard AK growth model with public capital. In the model, the government optimizes the tax rate, while individuals optimize tax evasion. It studies tax rate, tax evasion and economic growth, and compares them with otherwise identical economies except those without tax evasion. It inquires into the effects of three government policies on tax rate, tax evasion, and economic growth. It finds that an increase in both unit cost of tax evasion and punishme...

Cellular Automaton Modeling of Dendritic Growth Using a Multi-grid Method

International Nuclear Information System (INIS)

Natsume, Y; Ohsasa, K

2015-01-01

A two-dimensional cellular automaton model with a multi-grid method was developed to simulate dendritic growth. In the present model, we used a triple-grid system for temperature, solute concentration and solid fraction fields as a new approach of the multi-grid method. In order to evaluate the validity of the present model, we carried out simulations of single dendritic growth, secondary dendrite arm growth, multi-columnar dendritic growth and multi-equiaxed dendritic growth. From the results of the grid dependency from the simulation of single dendritic growth, we confirmed that the larger grid can be used in the simulation and that the computational time can be reduced dramatically. In the simulation of secondary dendrite arm growth, the results from the present model were in good agreement with the experimental data and the simulated results from a phase-field model. Thus, the present model can quantitatively simulate dendritic growth. From the simulated results of multi-columnar and multi-equiaxed dendrites, we confirmed that the present model can perform simulations under practical solidification conditions. (paper)

Nonlinear Growth Models in M"plus" and SAS

Science.gov (United States)

Grimm, Kevin J.; Ram, Nilam

2009-01-01

Nonlinear growth curves or growth curves that follow a specified nonlinear function in time enable researchers to model complex developmental patterns with parameters that are easily interpretable. In this article we describe how a variety of sigmoid curves can be fit using the M"plus" structural modeling program and the nonlinear…

Effects of salicylic acid elicitor against aphids on wheat and detection of infestation using infrared thermal imaging technique in Ismailia, Egypt

Directory of Open Access Journals (Sweden)

Mahmoud Farag Mahmoud

2015-04-01

Full Text Available Wheat (Triticum sativum L. is one of the most important cereal crops in Egypt. Insect pests, such as aphids, are major threats in terms of yield reduction. Induced resistance in wheat using salicylic acid as a foliar application was tested on the farm of the Faculty of Agriculture, Suez Canal University during 2012/2013 and 2013/2014 seasons. Three wheat cultivars, Gemeza 9, Sakha 93 and Giza 168, were sprayed three times with two concentrations of salicylic acid (SA, 200 mg/l and 100 mg/l, after early detection of aphid infestation by infrared thermal imaging. The infrared thermal imaging technique is based on significant differences in surface temperature between infested and healthy leaves. Imaging data are digital, and a computer program can be used to detect infestation rapidly. The results showed that aphid infestation raised the temperature of infested leaves, compared to healthy leaves. The range temperature difference between maximum and minimum temperatures (At was 1.1 ºC in healthy leaves and 3.9 ºC in infected leaves. The results of SA application showed significant differences in the mean number of aphids and in reduction of infestation among treatments and cultivars. The higher of the two SA rates (200 mg/l gave higher efficacy in the three cultivars than the lower rate (100 mg/l over the five weeks of trial. The highest efficacy against aphids was reached one week after application (86.28% for Giza, 85.89% for Gemesa and 70.54% for Sakha. Moreover, SA treatment enhanced the wheat yield of all three cultivars, compared with control plants. The three cultivars (Giza, Gemesa and Sakha produced higher yields than the control when sprayed with 200 mg/l SA. Their grain yield was 2,491.5, 2,455.0, and 2,327.25 kg/feddan (1 fed = 0.42 ha, respectively. In conclusion, infrared thermal imaging can be employed in identification of infected leaves. Also, the application of SA on wheat induced plant resistance to aphids.

Use of Early Ripening Cultivars to Avoid Infestation and Mass Trapping to Manage Drosophila suzukii (Diptera: Drosophilidae) in Vaccinium corymbosum (Ericales: Ericaceae).

Science.gov (United States)

Hampton, Emily; Koski, Carissa; Barsoian, Olivia; Faubert, Heather; Cowles, Richard S; Alm, Steven R

2014-10-01

Use of early ripening highbush blueberry cultivars to avoid infestation and mass trapping were evaluated for managing spotted wing drosophila, Drosophila suzukii (Matsumura). Fourteen highbush blueberry cultivars were sampled for spotted wing drosophila infestation. Most 'Earliblue', 'Bluetta', and 'Collins' fruit were harvested before spotted wing drosophila oviposition commenced, and so escaped injury. Most fruit from 'Bluejay', 'Blueray', and 'Bluehaven' were also harvested before the first week of August, after which spotted wing drosophila activity led to high levels of blueberry infestation. In a separate experiment, damage to cultivars was related to the week in which fruit were harvested, with greater damage to fruit observed as the season progressed. Attractant traps placed within blueberry bushes increased nearby berry infestation by 5%, irrespective of cultivar and harvest date. The significant linear reduction in infestation with increasing distance from the attractant trap suggests that traps are influencing fly behavior to at least 5.5 m. Insecticides applied to the exterior of traps, compared with untreated traps, revealed that only 10-30% of flies visiting traps enter the traps and drown. Low trap efficiency may jeopardize surrounding fruits by increasing local spotted wing drosophila activity. To protect crops, traps for mass trapping should be placed in a perimeter outside fruit fields and insecticides need to be applied to the surface of traps or on nearby fruit to function as an attract-and-kill strategy. © 2014 Entomological Society of America.

Effect of intercropping of maize in citrus orchards on citrus leaf miner infestation and population of its natural enemies

International Nuclear Information System (INIS)

Ahmed, S.; Khan, M.A.; Qasam, M.

2012-01-01

An experiment was conducted to determine the effect of intercropping of maize fodder in months of monsoon (July to October), in Faisalabad, Pakistan, on infestation of citrus leaf miner (CLM) (Phyllocnistis citrella Stanton) and its predators. Lemon, Kinnow, Grapefruit and Musambi intercropped with and without maize were selected for recording data on these insects. Percent leaf miner infestation and number of predators were recorded from randomly selected branches of citrus trees. Results showed that intercropped plots of each variety had low infestation of citrus miner and high population of coccinellids and Chrysoperla carnea and Musambi was 8.40+-0.144 and 12.72+-0.171 in intercropped and 9.12+-0.169 and 14.52+-0.200 in wihtout intercropped plots, respectively. Interaction of population of Chrysoperla carnea and coccinellids was non-significant for months, varieties and intercropping but was significant within months, varieties and intercropping. The possibility of using maize fodder as intercrop in autumn in citrus is discussed. (author)

Enterobius vermicularis (pinworm) infestation in a child presenting with symptoms of acute appendicitis: a wriggly tale!

Science.gov (United States)

Dunphy, Louise; Clark, Zoe; Raja, Mazhar H

2017-10-06

Acute appendicitis is the most common surgical emergency worldwide. However, it can still present a challenging diagnosis especially in the young, elderly and those individuals of reproductive age, thus encompassing a wide spectrum of varied clinical presentations. Parasitic infections of the appendix are a rare cause of acute appendicitis. However, they must be considered in children presenting with abdominal pain. We report a case of Enterobius vermicularis infestation mimicking the features of acute appendicitis in a 10-year-old girl. This case is a cautionary reminder of the importance of considering E. vermicularis infestation in children presenting with abdominal pain, but who do not have a significantly raised white cell count or high Alvarado scores. A history of anal pruritus is the most characteristic symptom, but the parasites can cause severe abdominal pain mimicking appendicitis. Prompt recognition and a high clinical index of suspicion are required to prevent an unnecessary appendicectomy. Caution is advised when performing a laparoscopic appendectomy, as in our case, to prevent contamination of the peritoneum. This infestation is easily treatable with mebendazole. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

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

Directory of Open Access Journals (Sweden)

Ronald W Raab

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

Stochastic modelling of avascular tumour growth and therapy

International Nuclear Information System (INIS)

Sahoo, S; Sahoo, A; Shearer, S F C

2011-01-01

In this paper, a generalized stochastic model for the growth of avascular tumours is presented. This model captures the dynamical evolution of avascular tumour cell subpopulations by incorporating Gaussian white noise into the growth rate of the mitotic function. This work generalizes the deterministic model proposed by Sherratt and Chaplain (2001 J. Math. Biol. 43 291) where they formulated a tumour model in an in vivo setting, in terms of continuum densities of proliferating, quiescent and necrotic cells. Detailed simulations of our model show that the inclusion of Gaussian noise in the original model of Sherratt and Chaplain substantially distorts the overall structure of the density profiles in addition to reducing the speed of tumour growth. Within this stochastic carcinogenesis framework the action of therapy is also investigated by replacing Gaussian white noise with a therapy term. We compare a constant therapy protocol with a logarithmic time-dependent protocol. Our results predict that a logarithmic therapy is more effective than the constant therapy protocol.

Surface-bounded growth modeling applied to human mandibles

DEFF Research Database (Denmark)

Andresen, Per Rønsholt

1999-01-01

This thesis presents mathematical and computational techniques for three dimensional growth modeling applied to human mandibles. The longitudinal shape changes make the mandible a complex bone. The teeth erupt and the condylar processes change direction, from pointing predominantly backward...... of the common features. 3.model the process that moves the matched points (growth modeling). A local shape feature called crest line has shown itself to be structurally stable on mandibles. Registration of crest lines (from different mandibles) results in a sparse deformation field, which must be interpolated...... old mandible based on the 3 month old scan. When using successively more recent scans as basis for the model the error drops to 2.0 mm for the 11 years old scan. Thus, it seems reasonable to assume that the mandibular growth is linear....

Growth Curve Models and Applications : Indian Statistical Institute

CERN Document Server

2017-01-01

Growth curve models in longitudinal studies are widely used to model population size, body height, biomass, fungal growth, and other variables in the biological sciences, but these statistical methods for modeling growth curves and analyzing longitudinal data also extend to general statistics, economics, public health, demographics, epidemiology, SQC, sociology, nano-biotechnology, fluid mechanics, and other applied areas.   There is no one-size-fits-all approach to growth measurement. The selected papers in this volume build on presentations from the GCM workshop held at the Indian Statistical Institute, Giridih, on March 28-29, 2016. They represent recent trends in GCM research on different subject areas, both theoretical and applied. This book includes tools and possibilities for further work through new techniques and modification of existing ones. The volume includes original studies, theoretical findings and case studies from a wide range of app lied work, and these contributions have been externally r...

Selection, calibration, and validation of models of tumor growth.

Science.gov (United States)

Lima, E A B F; Oden, J T; Hormuth, D A; Yankeelov, T E; Almeida, R C

2016-11-01

This paper presents general approaches for addressing some of the most important issues in predictive computational oncology concerned with developing classes of predictive models of tumor growth. First, the process of developing mathematical models of vascular tumors evolving in the complex, heterogeneous, macroenvironment of living tissue; second, the selection of the most plausible models among these classes, given relevant observational data; third, the statistical calibration and validation of models in these classes, and finally, the prediction of key Quantities of Interest (QOIs) relevant to patient survival and the effect of various therapies. The most challenging aspects of this endeavor is that all of these issues often involve confounding uncertainties: in observational data, in model parameters, in model selection, and in the features targeted in the prediction. Our approach can be referred to as "model agnostic" in that no single model is advocated; rather, a general approach that explores powerful mixture-theory representations of tissue behavior while accounting for a range of relevant biological factors is presented, which leads to many potentially predictive models. Then representative classes are identified which provide a starting point for the implementation of OPAL, the Occam Plausibility Algorithm (OPAL) which enables the modeler to select the most plausible models (for given data) and to determine if the model is a valid tool for predicting tumor growth and morphology ( in vivo ). All of these approaches account for uncertainties in the model, the observational data, the model parameters, and the target QOI. We demonstrate these processes by comparing a list of models for tumor growth, including reaction-diffusion models, phase-fields models, and models with and without mechanical deformation effects, for glioma growth measured in murine experiments. Examples are provided that exhibit quite acceptable predictions of tumor growth in laboratory

A mathematical model of the growth of uterine myomas.

Science.gov (United States)

Chen, C Y; Ward, J P

2014-12-01

Uterine myomas or fibroids are common, benign smooth muscle tumours that can grow to 10  cm or more in diameter and are routinely removed surgically. They are typically slow- growing, well-vascularised, spherical tumours that, on a macro-scale, are a structurally uniform, hard elastic material. We present a multi-phase mathematical model of a fully vascularised myoma growing within a surrounding elastic tissue. Adopting a continuum approach, the model assumes the conservation of mass and momentum of four phases, namely cells/collagen, extracellular fluid, arterial and venous phases. The cell/collagen phase is treated as a poro-elastic material, based on a linear stress-strain relationship, and Darcy's law is applied to describe flow in the extracellular fluid and the two vascular phases. The supply of extracellular fluid is dependent on the capillary flow rate and mean capillary pressure expressed in terms of the arterial and venous pressures. Cell growth and division is limited to the myoma domain and dependent on the local stress in the material. The resulting model consists of a system of nonlinear partial differential equations with two moving boundaries. Numerical solutions of the model successfully reproduce qualitatively the clinically observed three-phase "fast-slow-fast" growth profile that is typical for myomas. The results suggest that this growth profile requires stress-induced resistance to growth by the surrounding tissue and a switch-like cell growth response to stress. Analysis of large-time solutions reveal that while there is a functioning vasculature throughout the myoma, exponential growth results, otherwise power-law growth is predicted. An extensive survey of the effect of parameters on model solutions is also presented, and in particular, the enhanced growth caused by factors such as oestrogen is predicted by the model.

Growth Kinetics and Modeling of Direct Oxynitride Growth with NO-O2 Gas Mixtures

Energy Technology Data Exchange (ETDEWEB)

Everist, Sarah; Nelson, Jerry; Sharangpani, Rahul; Smith, Paul Martin; Tay, Sing-Pin; Thakur, Randhir

1999-05-03

We have modeled growth kinetics of oxynitrides grown in NO-O₂ gas mixtures from first principles using modified Deal-Grove equations. Retardation of oxygen diffusion through the nitrided dielectric was assumed to be the dominant growth-limiting step. The model was validated against experimentally obtained curves with good agreement. Excellent uniformity, which exceeded expected walues, was observed.

Parameter Estimates in Differential Equation Models for Population Growth

Science.gov (United States)

Winkel, Brian J.

2011-01-01

We estimate the parameters present in several differential equation models of population growth, specifically logistic growth models and two-species competition models. We discuss student-evolved strategies and offer "Mathematica" code for a gradient search approach. We use historical (1930s) data from microbial studies of the Russian biologist,…

Survival rate of Plodia interpunctella (Lepidoptera: Pyralidae: On different states of wheat and rye kernels previously infested by beetle pests

Directory of Open Access Journals (Sweden)

Vukajlović Filip N.

2017-01-01

Full Text Available The present study was undertaken to determine survival rate of Plodia interpunctella (Hübner, 1813, reared on different mechanical states of Vizija winter wheat cultivar and Raša winter rye cultivar, previously infested with different beetle pests. Wheat was previously infested with Rhyzopertha dominica, Sitophilus granarius, Oryzaephilus surinamensis and Cryptolestes ferrugineus, while rye was infested only with O. surinamensis. Kernels were tested in three different mechanical states: (A whole undamaged kernels; (B kernels already damaged by pests and (C original storage kernels (mixture of B and C type. No P. interpunctella adult emerged on wheat kernels, while 36 adults developed on rye kernels. The highest abundance reached beetle species who fed with a mixture of kernels damaged by pests and whole undamaged kernels. Development and survival rate of five different storage insect pests depends on type of kernels and there exist significant survivorship correlations among them.

Mudcake growth: Model and implications

KAUST Repository

Liu, Q.; Santamarina, Carlos

2017-01-01

cementing, and to prevent partial differential sticking. We developed a robust mud cake growth model for water-based mud based on wide stress-range constitutive equations within a Lagrangian reference system to avoid non-natural moving boundary solutions

Patterns of gall infestation in Heteropterys byrsonimifolia A. Juss. in a forest-savannah ecotone

Directory of Open Access Journals (Sweden)

Marcela de Castro Nunes Santos Terra

Full Text Available ABSTRACT Galls are the result of a specific interaction between an inducer and a host plant. The species Heteropterys byrsonimifolia A. Juss. occurs in abundance in semideciduous seasonal forest ecotones and adjacent open formations. In the ecological reserve Quedas do Rio Bonito, located in the state of Minas Gerais, Brazil, this species is affected by a single gall morphotype. The present study aimed to evaluate whether the structural complexity of the host (test of the structural complexity hypothesis and the distance between hosts (test of the resource concentration hypothesis affect gall density in H. byrsonimifolia and to characterize the spatial distribution of the infestation. The results corroborate the two hypotheses tested, suggesting a metapopulation pattern of gall infestation in H. byrsonimifolia. Gallers were more successful in abrupt forest-savannah transition environments, which may be associated with greater stress-induced host vulnerability that plants usually experience in ecotones.

Therapeutic efficacy of milbemycin oxime/praziquantel oral formulation (Milbemax® against Thelazia callipaeda in naturally infested dogs and cats

Directory of Open Access Journals (Sweden)

Motta Bruna

2012-05-01

Full Text Available Abstract Background Over the last few decades, canine and feline thelaziosis caused by Thelazia callipaeda eye worms has gained the attention of the veterinary community due to the spread of this ocular infestation in geographical areas previously regarded as non endemic. The therapeutic efficacy of milbemycin oxime/praziquantel tablets (Milbemax® against T. callipaeda was tested in naturally infested dogs and cats. Methods From January 2009 to July 2011 a placebo controlled and randomized field study was conducted in T. callipaeda endemic areas of Switzerland (CH and Italy (ITA involving client-owned animals. Dogs (n = 56 and cats (n = 31 were physically examined at enrolment Day 0 (D0 and twice afterwards (D7 and D14. Infested animals were orally treated with Milbemax® or with placebo tablets on D0 and, if an animal was found still infested with T. callipaeda, also on D7. On D14 nematodes were flushed from the conjunctiva, identified and counted. Results Out of 56 dogs, 43 were included in the statistical analysis, whereas 13 were excluded because the products under investigation were not administered with food, as required by the label. On D7 and D14, 72.7% and 90.9% of treated dogs were eye worm free, whereas in the placebo group 95.2% and 76.2% still harbored nematodes, resulting in a mean percentage worm count reduction for the Milbemax® group of 86.1% and 96.8%, respectively. Both results were significantly higher (p = 0.0001 than the placebo group. Out of the 31 cats included in the study at D7 and D14, 53.3% and 73.3% treated with Milbemax® were free of T. callipaeda, while 81.3% and 73.3 in the placebo group were still harbouring eye worms, resulting in a mean percentage worm count reduction for the treated group of 62.2% and 80.0%, respectively. Both results were significantly higher (p = 0.0106 and p = 0.0043 than the placebo group. Conclusions The commercial formulation of milbemycin oxime at the minimal dose

Effects of gamma irradiation on pepper's volatile compounds sensory qualities and pest infestation control. Part of a coordinated programme in the Asian Regional Cooperative Project of Food Irradiation

International Nuclear Information System (INIS)

Khan, A.M.; Bahari Bin, I.

1984-04-01

The effects of gamma irradiation, packaging materials and storage time of black and white peppers on the infestation and reinfestation of microorganism and insects were evaluated. The samples were irradiated at the doses between 2 and 9 kGy. The packaging materials consisted of polypropylene woven bags laminated with thin polyethylene (PPE) and polyethylene bags (PE) of different thickness, 0.05, 01.2 and 0.17 mm. The jute bag was used as a control material. The changes of infestation and reinfestation status were observed for 6 months in Malaysia and for the next 2 months the changes were evaluated when the samples had reached Japan. Results obtained indicated that irradiation at a dose up to 9 kGy reduced the bacterial load of black pepper from 1.6x10 7 /g to 2 /g, while the dose of 6 kGy was required to reduce the population in white pepper from 2.3x10 4 /g to 2 /g. The original population of mould-yeast was relatively low (approx. 10 4 /g) and could be reduced to 2 /g at only 2 kGy. No problems and difficulties were faced with regard to the transportation of the peppers. However, prolonged storage time may encourage microbial growth, and 4 months of storage was a critical period for black pepper. Two species of Anobiidae infesting pepper had been identified, Lasioderma serricone (Fabricius) which made up 80% of the insect counts and Stegobium pamiceum (L.). However, at the doses applied and packaging materials used, there was no reinfestation for all but the material PPPE (no observation made for jute bags)

R.M. Solow Adjusted Model of Economic Growth

Directory of Open Access Journals (Sweden)

Ion Gh. Rosca

2007-05-01

Full Text Available Besides the models of M. Keynes, R.F. Harrod, E. Domar, D. Romer, Ramsey-Cass-Koopmans etc., the R.M. Solow model is part of the category which characterizes the economic growth. The paper proposes the study of the R.M. Solow adjusted model of economic growth, while the adjustment consisting in the model adaptation to the Romanian economic characteristics. The article is the first one from a three paper series dedicated to the macroeconomic modelling theme, using the R.M. Solow model, such as: “Measurement of the economic growth and extensions of the R.M. Solow adjusted model” and “Evolution scenarios at the Romanian economy level using the R.M. Solow adjusted model”. The analysis part of the model is based on the study of the equilibrium to the continuous case with some interpretations of the discreet one, by using the state diagram. The optimization problem at the economic level is also used; it is built up of a specified number of representative consumers and firms in order to reveal the interaction between these elements.

Effectiveness of a chemical herder in association with in-situ burning of oil spills in ice-infested water

DEFF Research Database (Denmark)

van Gelderen, Laurens; Fritt-Rasmussen, Janne; Jomaas, Grunde

2017-01-01

The average herded slick thickness, surface distribution and burning efficiency of a light crude oil were studied in ice-infested water to determine the effectiveness of a chemical herder in facilitating the in-situ burning of oil. Experiments were performed in a small scale (1.0m2) and an interm......The average herded slick thickness, surface distribution and burning efficiency of a light crude oil were studied in ice-infested water to determine the effectiveness of a chemical herder in facilitating the in-situ burning of oil. Experiments were performed in a small scale (1.0m2...

Essential oils of indigenous plants protect livestock from infestations of Rhipicephalus appendiculatus and other tick species in herds grazing in natural pastures in western Kenya

NARCIS (Netherlands)

Wanzala, Wycliffe; Hassanali, Ahmed; Mukabana, Wolfgang Richard; Takken, Willem

2018-01-01

The effects of formulated essential oils of Tagetes minuta and Tithonia diversifolia on Rhipicephalus appendiculatus infesting livestock were evaluated in semi-field experiments. Forty-five zebu cattle naturally infested with ticks were randomly selected from 15 herds, three animals from each. Of

The effect of adjuvants and reduced rates of crop protection agents on weed infestation, health and lodging of spring barley (Hordeum sativum L.

Directory of Open Access Journals (Sweden)

Cezary A. Kwiatkowski

2012-12-01

Full Text Available A field experiment in the cultivation of spring barley was carried out in the period 2007-2009 at the Experimental Farm in Czesławice (central Lublin region on grey-brown podzolic soil derived from loess (soil quality class II. The study involved 3 rates of herbicides, growth retardant and fungicides (100%, 75%, 50% as well as different adjuvant types (oil, surface- active, mineral adjuvant. Plots without any adjuvant were the control treatment. Conventional tillage was used, while mineral fertilization was adjusted to high initial soil nutrient availability. A hypothesis was made that the reduction of pesticide rates by 25-50%, with the simultaneous addition of adjuvants, would allow health, weed infestation and lodging of spring barley to be maintained at a level similar to that obtained under the conditions when maximum rates are applied without any adjuvant. It was also assumed that particular adjuvants could show different interactions with the tested groups of crop protection agents. It was proved that the application of full recommended rates of pesticides gave the best values of the indicators relating to weed infestation, health and lodging of spring barley. However, thanks to the addition of adjuvants to the spray solution, the application of pesticide doses reduced by 25% produced similar results. A higher reduction of pesticide rates (by 50% had an adverse effect on the traits in question. In such case, there was noted higher weed infestation of the spring barley crop, compensation of some weed species, and increased stem-base infection by the fungal disease complex. On the other hand, less radical changes were observed in the case of spring barley lodging. The above-mentioned situation occurred in spite of the fact that the action of pesticides was aided by adjuvants. From the group of adjuvants under comparison, the oil adjuvant Atpolan 80 EC showed the best interaction with the crop protection agents under consideration.

A Finite Element Model for Mixed Porohyperelasticity with Transport, Swelling, and Growth.

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Michelle Hine Armstrong

Full Text Available The purpose of this manuscript is to establish a unified theory of porohyperelasticity with transport and growth and to demonstrate the capability of this theory using a finite element model developed in MATLAB. We combine the theories of volumetric growth and mixed porohyperelasticity with transport and swelling (MPHETS to derive a new method that models growth of biological soft tissues. The conservation equations and constitutive equations are developed for both solid-only growth and solid/fluid growth. An axisymmetric finite element framework is introduced for the new theory of growing MPHETS (GMPHETS. To illustrate the capabilities of this model, several example finite element test problems are considered using model geometry and material parameters based on experimental data from a porcine coronary artery. Multiple growth laws are considered, including time-driven, concentration-driven, and stress-driven growth. Time-driven growth is compared against an exact analytical solution to validate the model. For concentration-dependent growth, changing the diffusivity (representing a change in drug fundamentally changes growth behavior. We further demonstrate that for stress-dependent, solid-only growth of an artery, growth of an MPHETS model results in a more uniform hoop stress than growth in a hyperelastic model for the same amount of growth time using the same growth law. This may have implications in the context of developing residual stresses in soft tissues under intraluminal pressure. To our knowledge, this manuscript provides the first full description of an MPHETS model with growth. The developed computational framework can be used in concert with novel in-vitro and in-vivo experimental approaches to identify the governing growth laws for various soft tissues.

A Finite Element Model for Mixed Porohyperelasticity with Transport, Swelling, and Growth.

Science.gov (United States)

Armstrong, Michelle Hine; Buganza Tepole, Adrián; Kuhl, Ellen; Simon, Bruce R; Vande Geest, Jonathan P

2016-01-01

The purpose of this manuscript is to establish a unified theory of porohyperelasticity with transport and growth and to demonstrate the capability of this theory using a finite element model developed in MATLAB. We combine the theories of volumetric growth and mixed porohyperelasticity with transport and swelling (MPHETS) to derive a new method that models growth of biological soft tissues. The conservation equations and constitutive equations are developed for both solid-only growth and solid/fluid growth. An axisymmetric finite element framework is introduced for the new theory of growing MPHETS (GMPHETS). To illustrate the capabilities of this model, several example finite element test problems are considered using model geometry and material parameters based on experimental data from a porcine coronary artery. Multiple growth laws are considered, including time-driven, concentration-driven, and stress-driven growth. Time-driven growth is compared against an exact analytical solution to validate the model. For concentration-dependent growth, changing the diffusivity (representing a change in drug) fundamentally changes growth behavior. We further demonstrate that for stress-dependent, solid-only growth of an artery, growth of an MPHETS model results in a more uniform hoop stress than growth in a hyperelastic model for the same amount of growth time using the same growth law. This may have implications in the context of developing residual stresses in soft tissues under intraluminal pressure. To our knowledge, this manuscript provides the first full description of an MPHETS model with growth. The developed computational framework can be used in concert with novel in-vitro and in-vivo experimental approaches to identify the governing growth laws for various soft tissues.

Random-growth urban model with geographical fitness

Science.gov (United States)

Kii, Masanobu; Akimoto, Keigo; Doi, Kenji

2012-12-01

This paper formulates a random-growth urban model with a notion of geographical fitness. Using techniques of complex-network theory, we study our system as a type of preferential-attachment model with fitness, and we analyze its macro behavior to clarify the properties of the city-size distributions it predicts. First, restricting the geographical fitness to take positive values and using a continuum approach, we show that the city-size distributions predicted by our model asymptotically approach Pareto distributions with coefficients greater than unity. Then, allowing the geographical fitness to take negative values, we perform local coefficient analysis to show that the predicted city-size distributions can deviate from Pareto distributions, as is often observed in actual city-size distributions. As a result, the model we propose can generate a generic class of city-size distributions, including but not limited to Pareto distributions. For applications to city-population projections, our simple model requires randomness only when new cities are created, not during their subsequent growth. This property leads to smooth trajectories of city population growth, in contrast to other models using Gibrat’s law. In addition, a discrete form of our dynamical equations can be used to estimate past city populations based on present-day data; this fact allows quantitative assessment of the performance of our model. Further study is needed to determine appropriate formulas for the geographical fitness.

Prioritizing plant defence over growth through WRKY regulation facilitates infestation by non-target herbivores

Science.gov (United States)

Li, Ran; Zhang, Jin; Li, Jiancai; Zhou, Guoxin; Wang, Qi; Bian, Wenbo; Erb, Matthias; Lou, Yonggen

2015-01-01

Plants generally respond to herbivore attack by increasing resistance and decreasing growth. This prioritization is achieved through the regulation of phytohormonal signaling networks. However, it remains unknown how this prioritization affects resistance against non-target herbivores. In this study, we identify WRKY70 as a specific herbivore-induced, mitogen-activated protein kinase-regulated rice transcription factor that physically interacts with W-box motifs and prioritizes defence over growth by positively regulating jasmonic acid (JA) and negatively regulating gibberellin (GA) biosynthesis upon attack by the chewing herbivore Chilo suppressalis. WRKY70-dependent JA biosynthesis is required for proteinase inhibitor activation and resistance against C. suppressalis. In contrast, WRKY70 induction increases plant susceptibility against the rice brown planthopper Nilaparvata lugens. Experiments with GA-deficient rice lines identify WRKY70-dependent GA signaling as the causal factor in N. lugens susceptibility. Our study shows that prioritizing defence over growth leads to a significant resistance trade-off with important implications for the evolution and agricultural exploitation of plant immunity. DOI: http://dx.doi.org/10.7554/eLife.04805.001 PMID:26083713

Modelling the growth of a methanotrophic biofilm

DEFF Research Database (Denmark)

Arcangeli, J.-P.; Arvin, E.

1999-01-01

This article discusses the growth of methanotrophic biofilms. Several independent biofilm growths scenarios involving different inocula were examined. Biofilm growth, substrate removal and product formation were monitored throughout the experiments. Based on the oxygen consumption it was concluded...... that heterotrophs and nitrifiers co-existed with methanotrophs in the biofilm. Heterotrophic biomass grew on soluble polymers formed by the hydrolysis of dead biomass entrapped in the biofilm. Nitrifier populations developed because of the presence of ammonia in the mineral medium. Based on these experimental...... was performed on this model. It indicated that the most influential parameters were those related to the biofilm (i.e. density; solid-volume fraction; thickness). This suggests that in order to improve the model, further research regarding the biofilm structure and composition is needed....

Modelling of tomato stem diameter growth rate based on physiological responses

International Nuclear Information System (INIS)

Li, L.; Tan, J.; Lv, T.

2017-01-01

The stem diameter is an important parameter describing the growth of tomato plant during vegetative growth stage. A stem diameter growth model was developed to predict the response of plant growth under different conditions. By analyzing the diurnal variations of stem diameter in tomato (Solanum lycopersicum L.), it was found that the stem diameter measured at 3:00 am was the representative value as the daily basis of tomato stem diameter. Based on the responses of growth rate in stem diameter to light and temperature, a linear regression relationship was applied to establish the stem diameter growth rate prediction model for the vegetative growth stage in tomato and which was further validated by experiment. The root mean square error (RMSE) and relative error (RE) were used to test the correlation between measured and modeled stem diameter variations. Results showed that the model can be used in prediction for stem diameter growth rate at vegetative growth stage in tomato. (author)

Repeatability of measurements of removal of mite-infested brood to assess Varroa Sensitive Hygiene

Science.gov (United States)

Varroa Sensitive Hygiene is a useful resistance trait that bee breeders could increase in different populations with cost-effective and reliable tests. We investigated the reliability of a one-week test estimating the changes in infestation of brood introduced into highly selected and unselected co...

Termite Infestation Associated with Type of Soil in Pulau Pinang, Malaysia (Isoptera: Rhinotermitidae)

OpenAIRE

Majid, Abdul Hafiz Ab; Ahmad, Abu Hassan

2013-01-01

Nine soil samples from nine buildings infested with Coptotermes gestroi in Pulau Pinang, Malaysia, were tested for the type of soil texture. The soil texture analysis procedures used the hydrometer method. Four of nine buildings (44%) yielded loamy sand-type soil, whereas five of nine buildings (56%) contained sandy loam-type soil.

Termite infestation associated with type of soil in pulau pinang, malaysia (isoptera: rhinotermitidae).

Science.gov (United States)

Majid, Abdul Hafiz Ab; Ahmad, Abu Hassan

2013-12-01

Nine soil samples from nine buildings infested with Coptotermes gestroi in Pulau Pinang, Malaysia, were tested for the type of soil texture. The soil texture analysis procedures used the hydrometer method. Four of nine buildings (44%) yielded loamy sand-type soil, whereas five of nine buildings (56%) contained sandy loam-type soil.

Case report of oral cavity infestation in a 3-year old jackass with Limnatis nilotica from Ilam province, west of Iran

Directory of Open Access Journals (Sweden)

Mahmoud Bahmani

2014-06-01

Full Text Available Leeches (phylum: Annelida, class: hirudinea could infest wide range of livestock such as cow, buffalo, sheep, goat, horse, mule, ass, dog, pig and even human. In November 2013, a 3-year old jackass from Dehloran county, Ilam province, Iran, was infected through his mouth due to drinking spring water. Symptoms including stress, anxiety and tachycardia were seen. After examining oral cavity of jackass, a leech was observed in upper gum. The leech was measured after separation which was three inches in length. The leech was adult which has dark green with orange lines, and it was identified as Limnatis nilotica species. It seems that using spring, subterranean water, pond etc. is the main causes of livestock infestation with leech. Ranchers could be recommended to decontaminate leech waters to prevent further leech infestation cases.

Simple method of detecting sarcoptes scabiei var hominis mites among bedridden elderly patients suffering from severe scabies infestation using an adhesive-tape.

Science.gov (United States)

Katsumata, Kazuo; Katsumata, Kazumi

2006-01-01

Scabies infestation is very common among bedridden elderly patients. The standard method of diagnosis for scabies by scraping the skin requires some skill. Therefore, dermatologists employ this method. However, dermatologists are usually not present in most long-term nursing units. Thus, we tried to catch mites using a strong transparent adhesive tape commercially available for packing use as an alternative method for the diagnosis of severe scabies infestation. After firmly applying the adhesive side of the tape onto an appropriate skin lesion of patients, the tape was pulled off and transferred directly onto a slide for microscopy, affixing the adhered separated part of the corneal skin. When a massive outbreak of scabies infestation occurred in May 2004 at the nursing unit of K hospital with thirty-one bedridden elderly patients, we tried to detect scabies mite using an adhesive tape. We could detect mites from six patients using this tape method. The diagnosis was confirmed by the standard scraping method. By the tape method we could observe some mites moving around and also could see a striated structure with dark red or weak red color or gray color granule-like constitution on the body of some mites. We found mites only on the skin of the fingers and toes where the skin of a patient is thin. Recently, massive scabies infestation in elderly long-term residents has been reported elsewhere. This tape method is simple and useful for diagnosis of severe scabies infestation in long-term nursing units.

A literature review on growth models and strategies: The missing link in entrepreneurial growth

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Syed Fida Hussain Shah

2013-08-01

Full Text Available This study focuses on the importance of growth models, growth strategies, role of knowledge management system in the formulation of effective strategy for the enterprises following growth. Choice of an appropriate growth strategy is at the heart of any successful entrepreneurial venture. Selection of a strategy may be effective for one entrepreneur while it is not for other. Choice of Growth Strategy depends on various different factors, organisational context and environment which may vary from enterprise to enterprise. Resource based view is very important consideration for the entrepreneurs on the path of growth. Evaluation of all kind of resources helps them to grow their enterprises successfully. Selection of an appropriate growth strategy allows the entrepreneurs in overcoming growth challenges and avoiding the growth reversals and setbacks.

Interactions of seedborne bacterial pathogens with host and non-host plants in relation to seed infestation and seedling transmission.

Science.gov (United States)

Dutta, Bhabesh; Gitaitis, Ronald; Smith, Samuel; Langston, David

2014-01-01

The ability of seed-borne bacterial pathogens (Acidovorax citrulli, Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. tomato, Xanthomonas euvesicatoria, and Pseudomonas syringae pv. glycinea) to infest seeds of host and non-host plants (watermelon, tomato, pepper, and soybean) and subsequent pathogen transmission to seedlings was investigated. A non-pathogenic, pigmented strain of Serratia marcescens was also included to assess a null-interacting situation with the same plant species. Flowers of host and non-host plants were inoculated with 1 × 10(6) colony forming units (CFUs)/flower for each bacterial species and allowed to develop into fruits or umbels (in case of onion). Seeds harvested from each host/non-host bacterial species combination were assayed for respective bacteria by plating on semi-selective media. Additionally, seedlots for each host/non-host bacterial species combination were also assayed for pathogen transmission by seedling grow-out (SGO) assays under greenhouse conditions. The mean percentage of seedlots infested with compatible and incompatible pathogens was 31.7 and 30.9% (by plating), respectively and they were not significantly different (P = 0.67). The percentage of seedlots infested with null-interacting bacterial species was 16.8% (by plating) and it was significantly lower than the infested lots generated with compatible and incompatible bacterial pathogens (P = 0.03). None of the seedlots with incompatible/null-interacting bacteria developed symptoms on seedlings; however, when seedlings were assayed for epiphytic bacterial presence, 19.5 and 9.4% of the lots were positive, respectively. These results indicate that the seeds of non-host plants can become infested with incompatible and null-interacting bacterial species through flower colonization and they can be transmitted via epiphytic colonization of seedlings. In addition, it was also observed that flowers and seeds of non-host plants can be colonized by

Interactions of seedborne bacterial pathogens with host and non-host plants in relation to seed infestation and seedling transmission.

Directory of Open Access Journals (Sweden)

Bhabesh Dutta

Full Text Available The ability of seed-borne bacterial pathogens (Acidovorax citrulli, Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. tomato, Xanthomonas euvesicatoria, and Pseudomonas syringae pv. glycinea to infest seeds of host and non-host plants (watermelon, tomato, pepper, and soybean and subsequent pathogen transmission to seedlings was investigated. A non-pathogenic, pigmented strain of Serratia marcescens was also included to assess a null-interacting situation with the same plant species. Flowers of host and non-host plants were inoculated with 1 × 10(6 colony forming units (CFUs/flower for each bacterial species and allowed to develop into fruits or umbels (in case of onion. Seeds harvested from each host/non-host bacterial species combination were assayed for respective bacteria by plating on semi-selective media. Additionally, seedlots for each host/non-host bacterial species combination were also assayed for pathogen transmission by seedling grow-out (SGO assays under greenhouse conditions. The mean percentage of seedlots infested with compatible and incompatible pathogens was 31.7 and 30.9% (by plating, respectively and they were not significantly different (P = 0.67. The percentage of seedlots infested with null-interacting bacterial species was 16.8% (by plating and it was significantly lower than the infested lots generated with compatible and incompatible bacterial pathogens (P = 0.03. None of the seedlots with incompatible/null-interacting bacteria developed symptoms on seedlings; however, when seedlings were assayed for epiphytic bacterial presence, 19.5 and 9.4% of the lots were positive, respectively. These results indicate that the seeds of non-host plants can become infested with incompatible and null-interacting bacterial species through flower colonization and they can be transmitted via epiphytic colonization of seedlings. In addition, it was also observed that flowers and seeds of non-host plants can be

Modeling lodgepole pine radial growth relative to climate and genetics using universal growth-trend response functions.

Science.gov (United States)

McLane, Sierra C; LeMay, Valerie M; Aitken, Sally N

2011-04-01

Forests strongly affect Earth's carbon cycles, making our ability to forecast forest-productivity changes associated with rising temperatures and changes in precipitation increasingly critical. In this study, we model the influence of climate on annual radial growth using lodgepole pine (Pinus contorta) trees grown for 34 years in a large provenance experiment in western Canada. We use a random-coefficient modeling approach to build universal growth-trend response functions that simultaneously incorporate the impacts of different provenance and site climates on radial growth trends under present and future annual (growth-year), summer, and winter climate regimes. This approach provides new depth to traditional quantitative genetics population response functions by illustrating potential changes in population dominance over time, as well as indicating the age and size at which annual growth begins declining for any population growing in any location under any present or future climate scenario within reason, given the ages and climatic conditions sampled. Our models indicate that lodgepole pine radial-growth levels maximize between 3.9 degrees and 5.1 degrees C mean growth-year temperature. This translates to productivity declining by the mid-21st century in southern and central British Columbia (BC), while increasing beyond the 2080s in northern BC and Yukon, as temperatures rise. Relative to summer climate indices, productivity is predicted to decline continuously through the 2080s in all locations, while relative to winter climate variables, the opposite trend occurs, with the growth increases caused by warmer winters potentially offsetting the summer losses. Trees from warmer provenances, i.e., from the center of the species range, perform best in nearly all of our present and future climate-scenario models. We recommend that similar models be used to analyze population growth trends relative to annual and intra-annual climate in other large-scale provenance

Large-bodied Demodex mite infestation in 4 dogs.

Science.gov (United States)

Hillier, Andrew; Desch, Clifford E

2002-03-01

Large-bodied Demodex mites were detected in 4 dogs. The mites were readily detected in material obtained via deep skin scrapings and were most commonly found on the trunk. The mites were distinguishable from D. canis, because adult males were approximately 100% longer and adult females were approximately 50% longer than adult male and female D. canis mites, respectively. The large-bodied mites were found in the hair follicles, sebaceous ducts, and sebaceous glands in histologic sections of skin from 2 dogs. All dogs had adult-onset generalized demodicosis. Two dogs had coexistent iatrogenic hypercortisolism, 1 dog had hypothyroidism, and 1 dog did not have coexistent disease. Infestations responded to miticidal therapy, control of the coexistent disease, or both.

Infestation and Quantification of Ochratoxigenic Fungi in Barley and Wheat Naturally Contaminated with Ochratoxin A.

Science.gov (United States)

Kuruc, Julie; Hegstad, Justin; Lee, Hyun Jung; Simons, Kristin; Ryu, Dojin; Wolf-Hall, Charlene

2015-07-01

Cereal grains are a significant source of ochratoxin A (OTA) in the human diet. Multiple ochratoxigenic Aspergillus and Penicillium spp. have been reported as contaminants on various cereal grains around the world, although relatively few species dominate in any given location. Efforts to mitigate the risk of fungal contamination and OTA accumulation can be made pre- and postharvest. Still, a rapid and reliable screening method is sought that can be used to predict the OTA level of a sample and to inform risk assessments prior to processing. In this study, we assessed the efficacy of two OTA-related indices for OTA level prediction. Infestation rates were determined by direct plating for freshly harvested and stored barley, durum, and hard red spring wheat samples (n = 139) with known OTA levels. Presumptive ochratoxigenic isolates were tested for their ability to produce OTA. The nonribosomal peptide synthase (otanpsPN) involved in OTA biosynthesis was used to quantify ochratoxigenic fungi in barley and wheat. Viable Penicillium verrucosum was present in 45% of the samples. In total, 62.7% (n = 110) of the P. verrucosum isolates tested produced OTA on dichloran yeast extract sucrose 18% glycerol agar. Both OTA level and infestation rate (r = 0.30), as well as OTA level and otanpsPN concentration (r = 0.56), were weakly correlated. Neither infestation rate nor otanpsPN concentration is a reliable predictor of OTA level in a sample.

Multiplex PCR in determination of Opiinae parasitoids of fruit flies, Bactrocera sp., infesting star fruit and guava.

Science.gov (United States)

Shariff, S; Ibrahim, N J; Md-Zain, B M; Idris, A B; Suhana, Y; Roff, M N; Yaakop, S

2014-01-23

Malaysia is a tropical country that produces commercial fruits, including star fruits, Averrhoa carambola L. (Oxalidales: Oxalidaceae), and guavas, Psidium guajava L. (Myrtales: Myrtaceae). There is a high demand for these fruits, and they are planted for both local consumption and export purposes. Unfortunately, there has been a gradual reduction of these fruits, which has been shown to be related to fruit fly infestation, especially from the Bactrocera species. Most parasitic wasps (Hymenoptera: Braconidae: Opiinae) are known as parasitoids of fruit fly larvae. In this study, star fruits and guavas infested by fruit fry larvae were collected from the Malaysian Agricultural Research and Development Institute. The parasitized larvae were reared under laboratory conditions until the emergence of adult parasitoids. Multiplex PCR was performed to determine the braconid species using two mitochondrial DNA markers, namely cytochrome oxidase subunit I and cytochrome b. Two benefits of using multiplex PCR are the targeted bands can be amplified simultaneously using the same reaction and the identification process of the braconid species can be done accurately and rapidly. The species of fruit flies were confirmed using the COI marker. The results obtained from our study show that Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae), Fopius arisanus (Sonan), and Pysttalia incisi (Silvestri) were parasitoids associated with Bactrocera carambolae (Drew and Hancock) (Diptera: Tephritidae) infested star fruits. Fopius arisanus was also the parasitoid associated with Bactrocera papayae (Drew and Hancock) infested guavas. Maximum parsimony was been constructed in Opiinae species to compare tree resolution between these two genes in differentiating among closely related species. The confirmation of the relationship between braconids and fruit fly species is very important, recognized as preliminary data, and highly necessary in biological control programs. This is an

Mitigation of unionid mortality caused by zebra mussel infestation: cleaning of unionids

Science.gov (United States)

Schloesser, Don W.

1996-01-01

Exotic zebra mussels Dreissena polymorpha have infested and caused mortality of native unionids in the Great Lakes since 1986; no other such parasitism of native unionids occurs in North America. Survival of unionids threatened by zebra mussel infestation was tested by suspending uncleaned and cleaned unionids in nearshore waters of western Lake Erie. Survival was determined, and newly settled zebra mussels were removed from clean unionids at eight intervals that ranged from 21 d to 77 d between 5 July 1990 and 3 July 1991. After 1 year, survival rates of uncleaned and cleaned unionids were 0% and 42%, respectively. Of the 10 species examined, only indivduals from 3 species (Amblema plicata plicata, Fusconaia flava, and Quadrula quadrula) survived 1 year. These species have relatively thick shells, which may have contributed to their survival. Removal of newly settled zebra mussels may be important to unionid survival because 98% of the zebra mussels removed after the initial cleaning were small mussels (zebra mussels cause mortality of unionids, but the removal of zebra mussels from unionids is the only method known that successfully reduces unionid mortality in waters colonized by zebra mussels.

Adjusting the Stems Regional Forest Growth Model to Improve Local Predictions