Factors Affecting Residue-Film Bioassay of Insecticide Residues

1963 ◽  
Vol 46 (3) ◽  
pp. 530-542
Author(s):  
Yun-Pei Sun ◽  
Elmer R Johnson ◽  
Joe E Pankaskie ◽  
Norman W Earle ◽  
Juncx-Yi Tung Sun
Keyword(s):  
Exposure Time ◽  
Light Exposure ◽  
Effect Of Temperature ◽  
Factors Affecting ◽  
Test Container ◽  
Standard Curve ◽  
Insecticide Residues ◽  
Almost All

Abstract Many factors could affect the mortality of insects and bioassay results: preparation of extracts; method of preparing deposits; loss of volatile insecticides; effect of extractives and additives; age, stage, sex, weight, and species of insects; method of handling insects; size and position of test jars; food used during the test; effect of temperature, humidity, and light; exposure time; contamination of samples; interpretat i on of results; and method of calculating sensitivity. Almost all of these factors affect the mortality of insects, but only a few of them significantly interfere with the final bioassay results if a comparable series of standards is carried on side by side. To obtain more accurate results, all test jars, including the standards, should contain equal amounts of the same extractives; a corresponding standard curve should be prepared from an uncontaminated check for each series of tests; and insects used for each series of tests should be properly sampled from a mixture of several cultures. Within certain limits, the sensitivity of a bioassay may be easily increased by the manipulation of some factors, such as the volume of extract per test jar, age of test insects, size of test container, exposure time, and temperature.

Progress In The Practical Application Of Automated Image Analysis To Tem Negatives

1977 ◽  
Vol 35 ◽  
pp. 214-217
Author(s):  
F. A. Heckman ◽  
E. Redman ◽  
J.E. Connolly
Keyword(s):  
Image Analysis ◽  
Image Quality ◽  
Exposure Time ◽  
Image Contrast ◽  
Automated Image Analysis ◽  
Practical Application ◽  
Factors Affecting ◽  
High Image Quality ◽  
Qualitative Evidence ◽  
Comprehensive Study

In our initial publication on this subject1) we reported results demonstrating that contrast is the most important factor in producing the high image quality required for reliable image analysis. We also listed the factors which enhance contrast in order of the experimentally determined magnitude of their effect. The two most powerful factors affecting image contrast attainable with sheet film are beam intensity and KV. At that time we had only qualitative evidence for the ranking of enhancing factors. Later we carried out the densitometric measurements which led to the results outlined below.Meaningful evaluations of the cause-effect relationships among the considerable number of variables in preparing EM negatives depend on doing things in a systematic way, varying only one parameter at a time. Unless otherwise noted, we adhered to the following procedure evolved during our comprehensive study:Philips EM-300; 30μ objective aperature; magnification 7000- 12000X, exposure time 1 second, anti-contamination device operating.

Predicting cold-water bleaching in corals: role of temperature, and potential integration of light exposure

2020 ◽  
Vol 642 ◽  
pp. 133-146
Author(s):  
PC González-Espinosa ◽  
SD Donner
Keyword(s):  
Coral Bleaching ◽  
Cold Water ◽  
Light Exposure ◽  
Light Attenuation ◽  
Florida Keys ◽  
Cold Temperature ◽  
Warm Water ◽  
Coral Tissue ◽  
Effect Of Temperature ◽  
Type I

Warm-water growth and survival of corals are constrained by a set of environmental conditions such as temperature, light, nutrient levels and salinity. Water temperatures of 1 to 2°C above the usual summer maximum can trigger a phenomenon known as coral bleaching, whereby disruption of the symbiosis between coral and dinoflagellate micro-algae, living within the coral tissue, reveals the white skeleton of coral. Anomalously cold water can also lead to coral bleaching but has been the subject of limited research. Although cold-water bleaching events are less common, they can produce similar impacts on coral reefs as warm-water events. In this study, we explored the effect of temperature and light on the likelihood of cold-water coral bleaching from 1998-2017 using available bleaching observations from the Eastern Tropical Pacific and the Florida Keys. Using satellite-derived sea surface temperature, photosynthetically available radiation and light attenuation data, cold temperature and light exposure metrics were developed and then tested against the bleaching observations using logistic regression. The results show that cold-water bleaching can be best predicted with an accumulated cold-temperature metric, i.e. ‘degree cooling weeks’, analogous to the heat stress metric ‘degree heating weeks’, with high accuracy (90%) and fewer Type I and Type II errors in comparison with other models. Although light, when also considered, improved prediction accuracy, we found that the most reliable framework for cold-water bleaching prediction may be based solely on cold-temperature exposure.

scholarly journals Factors affecting clay dispersion in oxisols treated with vinasse

2016 ◽  
Vol 37 (6) ◽  
pp. 3997 ◽  
Author(s):  
Thadeu Rodrigues de Melo ◽  
Tiago Santos Telles ◽  
Walquiria Silva Machado ◽  
João Tavares Filho
Keyword(s):  
Sandy Soil ◽  
Physical Quality ◽  
Factors Affecting ◽  
Clay Dispersion ◽  
Water Dispersible ◽  
Dispersive Effect ◽  
Bivalent Cations ◽  
Chemical Attributes ◽  
Almost All ◽  
Dispersible Clay

Vinasse is a potassium-rich waste generated in large amounts by the ethanol production that, applied in the soil, can promote changes in water dispersible clay and in its physical quality. The aim of this study was to evaluate the clay dispersion of Oxisols after vinasse application and correlate it with some chemical attributes. Samples were collected in two Oxisols (155 and 471 g of clay kg-1), put in pots, received dosages of vinasse (0, 50, 100, 150 and 200 m3 ha-1) and remained incubated during 120 days. Phosphorous, organic carbon, pH H2O, pH KCl, pH CaCl2, Al3+, H+Al3+, Ca2+, Mg2+, K+, Na+, Delta pH and the proportion between monovalent and bivalent cations have been evaluated and correlated with the clay flocculation degree. Vinasse changed almost all chemical variables in both soils and increased the flocculation in the sandy soil, but did not change the clayey one. Delta pH, Mg2+ and K+ significantly correlated with the flocculation degree in the sandy soil. It is possible to conclude that the dispersive effect of K+ added by vinasse are irrelevant, considering the flocculant effect caused by the increment in Mg2+ and Delta pH after vinasse application.

Light Effects on Food

1990 ◽  
Vol 53 (5) ◽  
pp. 430-440 ◽  
Author(s):  
MIRAY BEKBÖLET
Keyword(s):  
Dairy Products ◽  
Light Exposure ◽  
Meat Products ◽  
Fats And Oils ◽  
Food Groups ◽  
Visual Appearance ◽  
Factors Affecting ◽  
Off Flavors ◽  
Interval Type ◽  
Induced Changes

Current research studies carried out on light-induced changes in dairy products, fats and oils, and meat products are reviewed. General factors affecting thus formed off-flavors in these food groups are the intensity of light, exposure interval, type of packaging, and some specific nutritive constituents. In dairy products, riboflavin degradation, losses of vitamin A and C are the major effects, whereas in fats and oils the effective constituents are ß-carotene, tocopherols, the undesirable flavors being related mainly to photosensitized oxidation. In case of meat products, the visual appearance seems to be the most important effect due to the formation of oxidized pigment metmyoglobin from oxymyoglobin upon light exposure. The effects of packaging materials and types on photooxidation are also being discussed for each of the above three food commodity groups.

scholarly journals AN EXPERIMENTAL STUDY ON THE RELAXATION OF BOLTS

2015 ◽  
Vol 16 (1) ◽  
Author(s):  
Muhammad Abid ◽  
Muhammad Shahid Khalil ◽  
Hafiz Abdul Wajid
Keyword(s):  
Dynamic Behaviour ◽  
Relaxation Behaviour ◽  
Bolted Joint ◽  
Factors Affecting ◽  
Elastic Interactions ◽  
Short And Long Term ◽  
The Many ◽  
Almost All ◽  
Static Behaviour

Loss of pre-load with time, commonly known as ‘Relaxation’ is an established phenomena. Behaviour of a bolted joint depends upon the pre-load in the bolts in use, not the pre-load introduced by the mechanic. Loss of pre-load is expected due to the many factors such as embedment relaxation, gasket creep, elastic interactions, and vibration loosening or stress relaxation. In a gasketed joint, due to the gasket flexibility, relaxation is always substantial during preliminary passes, as 80 to 100% loss is not uncommon in almost all the bolts, resulting in a dynamic behaviour. Pre-load in a gasketed joint is stabilized and retained to certain extent in the final passes only. In a non-gasketed joint, due to no gasket and no rotation its static behaviour is concluded. This paper highlights the factors affecting the amount of relaxation with time and presents important considerations that can reduce this. Both the short and long term relaxations are recorded and a ‘best fit’ model for relaxation behaviour is derived.

scholarly journals The Effects of Picking Up Primary School Pupils on Surrounding Street’s Traffic: A Case Study in Hanoi

2020 ◽  
Vol 14 (1) ◽  
pp. 237-250
Author(s):  
Dinh Hiep ◽  
Vu V. Huy ◽  
Teppei Kato ◽  
Aya Kojima ◽  
Hisashi Kubota
Keyword(s):  
Primary School ◽  
Traffic Safety ◽  
Traffic Congestion ◽  
Traffic Management ◽  
Primary Schools ◽  
Traffic Accidents ◽  
Binary Logistic Regression ◽  
Binary Logistic Regression Model ◽  
Factors Affecting ◽  
Almost All

Introduction: One of the significant characteristics of schools in Vietnam is that almost all parents send their children to school and/or pick up their children from school using private vehicles (motorcycles). The parents usually stop and park their vehicle on streets outside the school gates, which can lead to serious congestion and increases the likelihood of traffic accidents. Methods: The objective of this study is to find out factors affecting the picking up of pupils at primary school by evaluating the typical primary schools in Hanoi city. A binary logistic regression model was used to determine factors that influence the decision of picking up pupils and the waiting duration of parents. The behavior of motorcyclists during the process of picking up pupils at the primary school gate has been identified and analyzed in detail by the Kinovea software. Results and Discussion: The study showed that, on the way back home, almost all parents use motorbikes (89.15%) to pick up their children. During their waiting time (8.48 minutes in average), they made a lot of illegal parking actions on the street there by, causing a lot of “cognitive” errors and “crash” points surrounding in front of the primary school entrance gate. Risky picking-up behaviors were significantly observed, i.e. picking-up on opposite side of the school, making a U-turn, backing-up dangerously, parking on the middle of street, and parking on the street next to sidewalk). Conclusion: Based on the analyzed results, several traffic management measures have been suggested to enhance traffic safety and reduce traffic congestion in front of school gates. In addition, the results of the study will provide a useful reference for policymakers and authorities.

scholarly journals Factors Affecting the Perception and Practice of Iranian Nomadic and Semi-Nomadic Pastoralists in Regard to Biosecurity Practices in Sheep and Goat Farms: A Cross-Sectional and Prospective Study

Ruminants ◽  
2022 ◽  
Vol 2 (1) ◽  
pp. 54-73
Author(s):  
Zeinab Hatami ◽  
Richard A. Laven ◽  
Saeid Jafari-Gh. ◽  
Mahdi Moazez-Lesko ◽  
Pegah Soleimani ◽  
...  
Keyword(s):  
Prevention Measures ◽  
Extension Programs ◽  
Cross Sectional ◽  
Mortality And Morbidity ◽  
Factors Affecting ◽  
Nomadic Pastoralists ◽  
Almost All ◽  
Biosecurity Practices ◽  
Umbilical Cords ◽  
Annual Mortality

Preventing the spread of diseases between and within farms (biosecurity) is essential for minimizing animal mortality and morbidity, as well as for reducing the risk of spread of zoonotic diseases. These effects are even greater in countries such as Iran, which have to deal with multiple ongoing epidemics of infectious disease. However, there is currently no published information about biosecurity practices on sheep and goat farms in Iran in published research. The aim of this study was to collect such information and to identify some of the factors affecting biosecurity practices. Data were gathered using a checklist and in-depth interviews with 99 nomadic and semi-nomadic pastoralists. Regression analysis was used to identify the relationships between the collected variables and the biosecurity scores. The results showed that neither within- nor between-farm disease prevention measures were appropriately applied on most farms (median total score of total biosecurity was 37.3/90; Q1 = 29.0 and Q3 = 44.7). Almost all the farmers reported slaughtering animals on farms and nobody properly disposed of the bodies of the dead animals. Additionally, the majority of the participants did not disinfect the umbilical cords of newborns. Of the collected variables, the annual mortality rate was associated with most within-farm biosecurity practices. The increase in annual mortality rates was associated with the regular cleaning of troughs (p = 0.03), preventing feed and water from being contaminated by urine and feces (p = 0.02), providing a clean and dry place for animals to rest (p = 0.05) and disinfecting the navel cord (p = 0.03). The results of this survey suggest that there is a clear need for extension programs to enhance Iranian and sheep and goat farmers’ perceptions and practices regarding biosecurity measures.

scholarly journals Investigation of moderator factors in e-business adoption: A quantitative meta-analysis of moderating effects on the drivers of intention and behavior

2017 ◽  
Vol 14 (1) ◽  
pp. 75-102 ◽  
Author(s):  
Bostjan Sumak ◽  
Marjan Hericko ◽  
Zoran Budimac ◽  
Maja Pusnik
Keyword(s):  
Technology Acceptance ◽  
New Technologies ◽  
Causal Effect ◽  
Meta Analysis ◽  
Moderating Effect ◽  
Factors Affecting ◽  
Adoption Research ◽  
Acceptance Model ◽  
Almost All ◽  
Business Technology

E-business technology is becoming one of the most important global markets where e-business solutions will have to adapt to new technologies. The main objective in this study was to synthesize existing knowledge in the field of e-business technology acceptance and to understand differences in Technology Acceptance Model (TAM) related causal effect sizes for different e-business contexts. A quantitative meta-analysis of existing empirical research about factors affecting e-business adoption was conducted using 89 published papers that provided empirical data about causal relationships. A moderator analysis was carried out to investigate the moderating effect of four factors: consumer type, device type, continent and respondent type. The results of the study showed a moderating effect for all four proposed factors in almost all TAM-related causal paths. The study also showed that TAM is the most common theory being applied in e-business adoption research.

scholarly journals Phototoxicity of Ultraviolet-A against the Whitefly Bemisia tabaci and Its Compatibility with an Entomopathogenic Fungus and Whitefly Parasitoid

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Muhammad Musa Khan ◽  
Ze-Yun Fan ◽  
Dylan O’Neill Rothenberg ◽  
Jing Peng ◽  
Muhammad Hafeez ◽  
...  
Keyword(s):  
Biological Control ◽  
Bemisia Tabaci ◽  
Exposure Time ◽  
Entomopathogenic Fungus ◽  
Light Exposure ◽  
Adult Emergence ◽  
Biological Control Agents ◽  
Encarsia Formosa ◽  
Parasitism Rate ◽  
Invertebrate Pests

Ultraviolet (UV) radiation significantly affects insect life and, as a result, has been widely used to control different invertebrate pests. The current results demonstrate that when Bemisia tabaci first instar nymphs are exposed to UV-A light for 12, 24, 48, and 72 h, their developmental and biological parameters are negatively affected by UV-A exposure; the effect increased with an increase in exposure time. We hypothesized that UV-A light is compatible with other biological control agents. Results showed that when the entomopathogenic fungus Cordyceps fumosorosea was applied to third instar nymphs of B. tabaci previously exposed to UV-A light, the LC50 was 3.4% lower after 72 h of exposure to UV-A light compared to the control. However, when the fungus was exposed to UV-A light, its virulence decreased with an increase in UV-A exposure time. The parasitism rate of Encarsia formosa against 24 h UV-A-exposed third instar nymphs of B. tabaci increased while the adult emergence from parasitized nymphs was not affected after UV-A light exposure. Parasitism rate was significantly reduced however following E. formosa exposure to UV-A light; but again, adult emergence was not affected from parasitized nymphs. The percentage mortality of E. formosa increased with increasing exposure time to UV-A light. The enzyme activity of SOD, CAT, GST, and AChE and the energy reserve contents were negatively affected due to UV-A exposure. Collectively, this study has demonstrated that UV-A light significantly suppresses the immune system of B. tabaci and that UV-A light is compatible with other biological control agents if it is applied separately from the biological agent.

scholarly journals Factors Affecting Nursing Ability To Know Acute Coroner Syndrome In Emergency Installation

2018 ◽  
Vol 2 (1) ◽  
pp. 64-72
Author(s):  
Agus Riyadi ◽  
Karmiati Karmiati
Keyword(s):  
Emergency Department ◽  
Acute Coronary Syndrome ◽  
Emergency Services ◽  
P Value ◽  
Cross Sectional ◽  
Factors Affecting ◽  
Research Education ◽  
Coronary Syndrome ◽  
Coronary Syndromes ◽  
Almost All

Background: Coronary heart disease is the most cardiovascular disease that causes death in the world. The ability of nurses to recognize acute coronary syndromes is very necessary as part of the emergency services team. Purpose : The purpose of this study was to determine the description of the factors that influence the ability of nurses to know acute coronary syndrome in the emergency department of dr. Iskak Tulungagung. Methods : The design of this research is descriptive analytic with a cross sectional approach with the population of all nurses who work in the Emergency Department of dr. Iskak Tulungagung. The population is 55 nurses. The sample is all of the population, namely 55 respondents with total sampling sampling techniques. The data that has been collected is processed by a statistical test of Multivariate Analysis, Ordinal Regression with significance α = 0.05. Result : The results showed that most of the respondents with D3 education were 33 respondents (60.0%), almost all respondents had never attended ECG training in the amount of 50 respondents (90.9%) and almost half of the respondents had a working period of 2-5 year is 25 respondents (45.5%). The results of the regression regression analysis showed that the p-value = 0.855 on the education factor which means that H0 was accepted, the p-value = 0.041 in the training factor which means H1 is received, the p-value = 0.003 on the working period, which means that H1 is accepted Conclusion : Based on research, education does not affect the ability to recognize acute coronary syndrome. The education obtained will develop according to the increase in the work period and the frequent training that is obtained and practiced directly in real situations

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