scholarly journals Comparison of Rain Effects on Splash Dispersal of Three Colletotrichum Species Infecting Strawberry

1999 ◽  
Vol 89 (7) ◽  
pp. 555-563 ◽  
Author(s):  
N. Ntahimpera ◽  
L. L. Wilson ◽  
M. A. Ellis ◽  
L. V. Madden
Keyword(s):  
Flux Density ◽  
Soil Surface ◽  
Selective Medium ◽  
Spore Density ◽  
Deposition Flux ◽  
Closely Related Species ◽  
Colletotrichum Species ◽  
Splash Dispersal ◽  
Significant Difference ◽  
The Media

Rain simulation studies were performed to compare splash dispersal of three Colletotrichum species: C. acutatum (C. acutatum-O isolate from Ohio and C. acutatum-M isolate from Mississippi), C. fragariae (isolate from Mississippi), and C. gloeosporioides (isolate from Florida). Conidial dispersal was assessed by counting colonies formed from spore-bearing splash droplets deposited in sheltered petri plates containing a selective medium. Colonies were converted to number of conidia based on germination rates of spores on the media. The interpolated total number of dispersed conidia over a 61 min rain and 72 cm from the point source (Σ) was calculated. For all species, a rain intensity of 30-mm/h resulted in significantly greater dispersal than an intensity of 11-mm/h. C. fragariae had the lowest amount of spore dispersal, and C. acutatum-O had the highest dispersal. C. acutatum-M and C. gloeosporioides were intermediate in magnitude of conidial splash dispersal. However, differences were directly attributed to differences in spore density per fruit at the source. When Σ was corrected for source strength (Σr), the species were very similar, with only C. acutatum-M having a mean Σr significantly less than the others. Proportions and rates of spore removal (per minute) from source fruits were higher for C. acutatum-O and C. gloeosporioides than for other isolates. Wash-off rates of conidia deposited on healthy fruits were the same for all species. Deposition flux density of spores that had been uniformly sprayed over the entire soil surface of the experimental area was affected by species. A significant difference in means was observed between C. acutatum and C. fragariae—the latter had a somewhat lower flux density. This is the first demonstration that closely related species infecting the same plant species are similar in terms of splash dispersal.

scholarly journals Rain Splash Dispersal of Gibberella zeae Within Wheat Canopies in Ohio

2004 ◽  
Vol 94 (12) ◽  
pp. 1342-1349 ◽  
Author(s):  
P. A. Paul ◽  
S. M. El-Allaf ◽  
P. E. Lipps ◽  
L. V. Madden
Keyword(s):  
Flux Density ◽  
Soil Surface ◽  
Selective Medium ◽  
Gibberella Zeae ◽  
Spore Density ◽  
Rain Intensity ◽  
Head Blight ◽  
Splash Dispersal ◽  
Rain Splash ◽  
Maize Kernels

Rain splash dispersal of Gibberella zeae, causal agent of Fusarium head blight of wheat, was investigated in field studies in Ohio between 2001 and 2003. Samplers placed at 0, 30, and 100 cm above the soil surface were used to collect rain splash in wheat fields with maize residue on the surface and fields with G. zeae-infested maize kernels. Rain splash was collected during separate rain episodes throughout the wheat-growing seasons. Aliquots of splashed rain were transferred to petri dishes containing Komada's selective medium, and G. zeae was identified based on colony and spore morphology. Dispersed spores were measured in CFU/ml. Intensity of splashed rain was highest at 100 cm and ranged from 0.2 to 10.2 mm h-1, depending on incident rain intensity and sampler height. Spores were recovered from splash samples at all heights in both locations for all sampled rain events. Both macroconidia and ascospores were found based on microscopic examination of random samples of splashed rain. Spore density and spore flux density per rain episode ranged from 0.4 to 40.9 CFU cm-2 and 0.4 to 84.8 CFU cm-2 h-1, respectively. Spore flux density was higher in fields with G. zeae-infested maize kernels than in fields with maize debris, and generally was higher at 0 and 30 cm than at 100 cm at both locations. However, on average, spore flux density was only 30% lower at 100 cm (height of wheat spikes) than at the other heights. The log of spore flux density was linearly related to the log of splashed rain intensity and the log of incident rain intensity. The regression slopes were not significantly affected by year, location, height, and their interactions, but the intercepts were significantly affected by both sampler height and location. Thus, our results show that spores of G. zeae were consistently splash dispersed to spike heights within wheat canopies, and splashed rain intensity and spore flux density could be predicted based on incident rain intensity in order to estimate inoculum dispersal within the wheat canopy.

Status and development prospects of standard means for reproducing units of volumetric activity of radon and thoron and radon flux density from the soil surface

2020 ◽  
pp. 69-73
Author(s):  
S.G. Birjukov ◽  
O.I. Kovalenko ◽  
A.A. Orlov
Keyword(s):  
Flux Density ◽  
Soil Surface ◽  
National Standards ◽  
Measuring Instruments ◽  
Volumetric Activity ◽  
Standard Means ◽  
Radon Flux ◽  
Technical Solutions ◽  
Development Prospects ◽  
Physical Principles

The approach to creating standard means for reproducing units of volumetric activity of radon and thoron and flux density of radon from the soil surface is described based on the physical principles of reproducing these units of quantities and using as technical means for reproducing bubblers with a radioactive solution of radium salt, reference capacities of known volume, emanation chambers for generation of a toron, a gamma spectrometer with a semiconductor detector from highly pure germanium and radon radiometers. Reproduction consists in the physical realization of units in accordance with their definition as applied to the formation of radon and thoron in the radioactive rows of radium and thorium. The proposed approach will allow to determine the structural, structural and other technical solutions of standard measuring instruments, as well as specific techniques and methods of working with them. The creation of standard tools and technologies for reproducing units of volumetric activity of radon and thoron and the density of radon flux from the soil surface will ensure the unity and reliability of measurements in the field of ionizing radiation, traceability of units and bringing the characteristics of national standards in line with world achievements.

In silico Defining the Repeat-containing Proteins in the Acinetobacter baumannii Proteome, a Great Reservoir of Templates for Synthetic Biology

2019 ◽  
Vol 13 (2) ◽  
pp. 149-158
Author(s):  
Mohammad Reza Rahbar ◽  
Mahboubeh Zarei ◽  
Navid Nezafat ◽  
Manica Negahdaripour ◽  
Younes Ghasemi
Keyword(s):  
Acinetobacter Baumannii ◽  
Drug Targets ◽  
Closely Related Species ◽  
Great Ability ◽  
Repeat Proteins ◽  
Significant Difference ◽  
Biological Determinants ◽  
Tandem Repeat Proteins ◽  
Diagnostic Approaches ◽  
Novel Therapeutic

Background: Acinetobacter baumannii is an important nosocomial pathogen with great ability to resist antibiotics. Tandem repeat proteins, abundant in prokaryotic proteomes, attract attention due to their role in virulence and various biological processes. Defining repeat- containing proteins may pave the way to find novel therapeutic targets as well as vaccine candidate and give pieces of evidence of mechanisms of evolution and adaptation of organisms to various environmental conditions. Objective: In the present study, we employed bioinformatics tools to define repeatcontaining proteins within A. baumannii proteome for emphasizing the existence of natural sources for synthesizing novel therapeutic and diagnosis material. Results: We defined various kinds of repeat modules in a number of proteins and compared the abundance of these proteins in some closely related species. No significant difference was observed in the count of repeat-containing proteins in different species. But the existence of some important virulence factors is mentionable in our screening. Conclusion: Repeat containing proteins are important biological determinants of A. baumannii and are well worth researching for finding drug targets and vaccine candidates. These proteins can be served as a template for designing and synthesizing peptides for therapeutic and diagnostic approaches.

scholarly journals Survival of Fusarium moniliforme, F. proliferatum, and F. subglutinans in Maize Stalk Residue

1998 ◽  
Vol 88 (6) ◽  
pp. 550-555 ◽  
Author(s):  
T. K. Cotten ◽  
G. P. Munkvold
Keyword(s):  
Fusarium Moniliforme ◽  
Fusarium Species ◽  
Soil Surface ◽  
Selective Medium ◽  
Burial Depth ◽  
Linear Pattern ◽  
Maize Field ◽  
Continuous Maize ◽  
Maize Plants

The roles of residue size and burial depth were assessed in the survival of Fusarium moniliforme, F. proliferatum, and F. subglutinans in maize stalk residue. Stalk pieces (small or large sizes) were soaked in a spore suspension of F. moniliforme, F. proliferatum, or F. subglutinans and placed in a field on the soil surface or buried at 15- or 30-cm depths. Residue pieces were recovered periodically, cultured on a selective medium, and microscopically examined for the presence of the inoculated Fusarium species. After 630 days, the inoculated Fusarium species were recovered from 0 to 50% of the inoculated stalk pieces in a long-term, continuous maize field, from 0 to 28% of the inoculated stalk pieces placed in a maize/soybean/oat rotation field, and from 0 to 25% of the noninoculated stalk pieces at both locations. Residue size and residue depth had significant effects on survival, but there were significant interactions among strain, depth, residue size, and time. Up to 343 days after placement in the field, survival of the three Fusarium species was not consistently different between buried residues and surface residues, but after 630 days, survival was greater from surface residues. Overall, fungus survival decreased more slowly in the surface residues than in the buried residues. Linear coefficients of determination ranged from 0.35 to 0.82 for the surface residues and from 0.81 to 0.98 for the buried residues. Decline in survival over time followed a more linear pattern in buried residues than in surface residues. Vegetative compatibility tests confirmed that F. moniliforme, F. proliferatum, and F. subglutinans strains can survive at least 630 days in surface or buried maize residue. These results demonstrate that maize residue can act as a long-term source of inoculum for infection of maize plants by these three Fusarium species.

scholarly journals A PRELIMINARY LOOK AT THE STRUCTURAL DIFFERENCES OF HIGHER EDUCATION CLASSROOM COMMUNITIES IN TRADITIONAL AND ALN COURSES

2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Alfred P. Rovai
Keyword(s):  
Adult Learners ◽  
Classroom Community ◽  
Asynchronous Learning ◽  
Learning Effectiveness ◽  
Graduate Courses ◽  
Asynchronous Learning Network ◽  
Face To Face ◽  
Significant Difference ◽  
The Media ◽  
Classroom Communities

This preliminary study again provides evidence that it is the method and not the media that matters the most in learning effectiveness. The present work examines classroom community in order to determine how sense of community differs between students enrolled in traditional face-to-face and those enrolled in asynchronous learning network (ALN) courses. Subjects consist of 326 adult learners who were enrolled in a mix of 14 undergraduate and graduate courses at two urban universities. As operationalized by the Sense of Classroom Community Index (SCCI), there appears no significant difference in classroom community between the two groups of subjects. However, a discriminant analysis shows a significant overall difference in community structure between the two groups. Variations between groups on feelings of similarity of needs, recognition, importance of learning, connectedness, friendship, thinking critically, safety, acceptance, group identity, and absence of confusion are the characteristics contributing mostly to this difference in learning effectiveness.

scholarly journals Improving The Knowledge Of Primary School Children On Fourth Grade Stundents About Vegetables And Fruits And Attraction Of Puzzle Media In SDN Mekarjaya I

2017 ◽  
Vol 8 (2) ◽  
pp. 134-145
Author(s):  
Wiena Arynda ◽  
Rosmida M Marbun
Keyword(s):  
School Children ◽  
Fruits And Vegetables ◽  
Fourth Grade ◽  
Primary School Children ◽  
P Value ◽  
Significant Difference ◽  
Fourth Grade Students ◽  
Before And After ◽  
The Media ◽  
Vegetables And Fruits

In Indonesia, 93.5% of the population aged ≥10 years still consume less fruits and vegetables 5 servings per day for 7 days a week (RISKESDAS, 2013).  The preliminary study conducted at SDN Mekarjaya I shows that the level of knowledge of school children about vegetables and fruits by 60% is still low and 93.3% of vegetable and fruit consumption is still lacking. In addition, SDN Mekarjaya I has never been used as a place of prior research. Therefore, it is necessary to conduct research on the knowledge of fruit vegetables in the fourth grade students of SDN Mekarjaya I. One of them is by doing counseling with the media of puzzle game. This research was conducted to know the increase of knowledge about vegetables and fruits before and after given counseling with puzzle game media in fourth grade students of SDN Mekarjaya I. This research was conducted by Pre-exsperiment method using "One group pretest and posttest" research design. Sampling by purposive sampling is 66 people. The statistical test used is paired sample t-test. Based on the results of the analysis shows that there is a significant difference of knowledge where p-value 0.000 or p <0,05 means there is a meaningful difference between before and after given counseling with puzzle game media.This puzzle game media can be developed by the teachers as a medium of learning in the classroom so that students are more motivated in following the learning process and make students do not feel bored

scholarly journals The Effectiveness of the Application of Rock Painting Activities in Developing the Creativity of Children aged 5-6 Years in Kindergarten

2021 ◽  
Vol 9 (4) ◽  
pp. 561
Author(s):  
Mayolanda Hesti ◽  
Ismaniar Ismaniar
Keyword(s):  
T Test ◽  
Test Design ◽  
Key Factors ◽  
Learning Methods ◽  
Significant Difference ◽  
Experimental Learning ◽  
Post Test ◽  
Research Population ◽  
The Media ◽  
Quasi Experiment

The study was set back by the low the creativity of children age 5-6 years in the Adzkia Air Bangis. one of the key factors this is suspected because it is not suitable or the media used by the teacher is not interestig. This study aims to determine the effectiveness of the application of rock painting activities in developing the creativity of children aged 5-6 years in kindergarten Adzkia Air Bangis. the type of research is quantitative usng pseudo-experiment methods (quasi experiment) with pre-test design and post-test. The research population is 55 people. While the sampel 10 children. Sampling retrieval techniques are used sampling samples. The data uses t-test samples samples. As a result of the coclusion to the data collaction and management, 1) before being given an treatment (pre-test) the development of children’s creativity can be categorized as starting to develop but has not developed as expected. This is based on the result of research by researchers at Adzkia Air Bangis Kindergarten 2) after being given treatment (post-test) the development of chidren’s creativity can be categorized as developing according to expectations. 3) there is significant difference between the result of the pre-test and post-test after doing the paired sampe t-test sig 0,000 < 0,05.  Advice for teachers helping teachers by using experimental learning methods to develop the creativity of children aged 5-6 years trough rock painting activities. 

scholarly journals Effects of a Cover Crop on Splash Dispersal of Colletotrichum acutatum Conidia

1998 ◽  
Vol 88 (6) ◽  
pp. 536-543 ◽  
Author(s):  
N. Ntahimpera ◽  
M. A. Ellis ◽  
L. L. Wilson ◽  
L. V. Madden
Keyword(s):  
Cover Crop ◽  
Bare Soil ◽  
Selective Medium ◽  
Planting Density ◽  
Colletotrichum Acutatum ◽  
Type Model ◽  
Parameter Estimates ◽  
Diffusion Type ◽  
Tall Grass ◽  
Splash Dispersal

A rain simulator, with generated rains of 11 and 30 mm/h, was used to determine the effect of a cover crop or intercrop on the splash dispersal of Colletotrichum acutatum conidia. Dispersal through sudangrass, which can be used as a ‘living mulch’, was tested at two planting densities (140 or 280 kg/ha) and two heights (5 and 20 cm) and compared with a control consisting of a bare soil. Dispersal of C. acutatum conidia was assessed by counting colonies formed from spore-bearing splash droplets deposited in sheltered petri plates containing a selective medium. Both a cover crop and rain intensity significantly affected splash dispersal as measured by the interpolated total number of colonies (denoted by Σ) from 0 to 72 cm from the inoculum source and in a time span of 61 min of generated rain (P < 0.001). However, there was no significant interaction of cover crop and intensity (P > 0.90). Dispersal with a 30-mm/h rain was higher than dispersal with a 11-mm/h rain, and presence of a cover crop significantly reduced dispersal compared with bare soil (P < 0.001). Of the treatments with sudangrass, cover crop planting density did not affect dispersal overall, but there was greater spore dispersal with the taller sudangrass at the higher planting density, due in part to the higher rate of water splashing with the tall grass compared with the short grass. Spore deposition in the petri plates could be functionally related to distance and time using a diffusion-type model, and parameter estimates could be used to explain the effects of cover crop on Σ. Although the relationship between cover crop properties and splash dispersal is complex, results show the potential beneficial effects of the cover crop on disease management.

Abstract 102: Granular Media Calcinosis in the Aortic Wall of Patients With Bicuspid and Tricuspid Aortic Valves

2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
Sandy von Salisch ◽  
Josephina Haunschild ◽  
Martin Misfeld ◽  
Michael A Borger ◽  
Stefan Dhein ◽  
...  
Keyword(s):  
Aortic Valve ◽  
Bicuspid Aortic Valve ◽  
Granular Media ◽  
Aortic Wall ◽  
Aortic Disease ◽  
Dissecting Aneurysm ◽  
Media Thickness ◽  
Significant Difference ◽  
The Media ◽  
Aneurysm Dissection

Background: Bicuspid aortic valve is the most frequent congenital cardiac abnormality and associated with proximal aortic disease (i.e. aneurysm, dissection or rupture). Granular media calcinosis(GMC)--suggested to increase stiffness and play a pathogenetic role in dissecting aneurysm--has not yet been quantified in BAV. Methods: Specimen of the proximal aortic wall from 76 patients--32 with tricuspid (TAV) and 44 with bicuspid aortic valve (BAV)--were obtained during surgery to quantify media thickness and GMC by von Kossa staining (panel C), comparing the convexity (Cvx) and concavity (Ccv) in BAV vs. TAV. Results: Interlamellar GMC affected the most central layers of the media and those adjacent to the outer adventitia with a doubling within both--the Cvx and Ccv--of pts with BAV compared to patients with TAV (13.3±9.6 vs. 6.6±7.4 and 12.8±10.8 vs. 6.4±7.1; p<0.05, panel A) was seen, but neither a difference in calcification between the Ccx and the Ccv side within the BAV nor the TAV group. No association between age and calcification grade , neither in the Cvx nor the Ccv (r=0.132, p=0.218 and 0.103, p=0.341) was seen. There was a significant difference in the total media thickness between BAV and TAV at the Cvx (867±162μm vs . 993±158μm; p<0.05) and the Ccv (1005 ± 236 vs 1223 ± 217μm; p<0.05, panel B). Independent of aortic valve morphology, the Cvx was thinner than the Ccv side (TAV: 993 ± 158 vs.1223 ± 217μm; p<0.001; BAV: 869 ± 162 vs.1005 ± 236μm; p<0.05, panel B). Conclusion: BAVs had significantly thinner media and twice as much GMC than their tricuspid peers possibly associated with the loosening of the bond between the elastic lamellae causing a decrease in elasticity possibly explaining a higher risk for dissection and rupture.

scholarly journals 712. Activity of Exebacase (CF-301) Against Methicillin-Resistant Staphylococcus aureus (MRSA) Biofilms on Orthopedic Kirschner Wires

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S320-S320
Author(s):  
Melissa J Karau ◽  
Suzannah Schmidt-Malan ◽  
Jayawant Mandrekar ◽  
Dario Lehoux ◽  
Raymond Schuch ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Bactericidal Activity ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Kirschner Wires ◽  
Carrier Solution ◽  
Time Points ◽  
Significant Difference ◽  
Peptidoglycan Cell Wall ◽  
The Media ◽  
K Wires

Abstract Background Orthopedic foreign body-associated infection can be difficult to treat due to the formation of biofilms protecting microorganisms from both antimicrobials and the immune system. Exebacase (EXE) is a phage-derived lysin which acts as a direct lytic agent by hydrolyzing the peptidoglycan cell wall of Staphylococcus aureus. In this study, the activity of EXE was evaluated in comparison to daptomycin against MRSA biofilms on orthopedic Kirschner wires (K-wires). Methods MRSA strain IDRL-6169 was studied; it has a MIC of 0.5 µg/mL for both daptomycin (DAP) and EXE. Biofilms were formed in 1 mL of 106 cfu/mL tryptic soy broth on 0.5x0.1 mm threaded stainless steel K-wires for 10 hours, after which the wires were removed from the media and placed into 0.04 mL of either DAP or EXE at 0 (vehicle only), 0.098, 0.98, or 9.8 mg/mL. DAP+EXE was also tested, each at 0.098 mg/mL. Bacteria were quantified after 0, 2, 4, 8, and 12 hours of incubation at 37ºC. Testing was performed in triplicate. Results were reported as log10 cfu/K-wire reduction relative to vehicle alone. A 3-log10 cfu/K-wire reduction was considered bactericidal. P-values were calculated using Kruskal–Wallis. Results The bacterial burden of vehicle alone ranged from 5.49- to 6.33-log10 cfu/K-wire at all time points. Bacterial reductions for each treatment compared with carrier solution are shown in the table. DAP showed no bactericidal activity. EXE showed bactericidal activity at all concentrations at all time points studied except 0.098 mg/mL at 8 hours. There was no significant difference between EXE at 0.098 and 0.98 mg/mL at any time point but EXE at 9.8 mg/mL did show superiority over the lower concentrations. DAP+EXE 0.098 mg/mL was bactericidal at all time points. Conclusion EXE showed a rapid effect against MRSA biofilms on orthopedic K-wires apparent within the first 2 hours of exposure and was more active than daptomycin alone at the same concentrations. Disclosures All authors: No reported disclosures.

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