fourth experiment
Recently Published Documents


TOTAL DOCUMENTS

125
(FIVE YEARS 26)

H-INDEX

21
(FIVE YEARS 2)

2021 ◽  
Vol 31 (5) ◽  
pp. 577-588
Author(s):  
Erin M.R. Clark ◽  
John M. Dole ◽  
Jennifer Kalinowski

Six experiments were conducted using three cultivars to investigate the impact of water electrical conductivity (EC) and the addition of nutrients to vase solutions on postharvest quality of cut rose (Rosa hybrids) stems. Postharvest quality of cut ‘Freedom’ rose stems was evaluated using solutions containing either distilled water with sodium chloride (DW+NaCl) or DW+NaCl with the addition of a commercial floral preservative (holding solution containing carbohydrates and biocide) to generate a range of EC values (Expts. 1 and 2). The third experiment compared the effect of different EC levels from the salts NaCl, sodium sulfate (Na2SO4), and calcium chloride (CaCl2). The fourth experiment investigated EC’s impact on rose stems with the addition of two rose cultivars (Charlotte and Classy). When ‘Freedom’ stems were subjected to DW+NaCl, the longest vase life was achieved with 0.5 dS·m–1. The addition of holding solution not only extended vase life but also counteracted the negative effects of high EC with maximum vase life occurring at 1.0 dS·m–1. Furthermore, stems in the holding solution experienced significantly less bent neck and the flowers opened more fully than those in DW. Stems placed in DW with a holding solution also experienced more petal bluing, pigment loss, necrotic edges, and wilting than those held in DW alone. This effect was likely due to increased vase life. Salt solutions containing Na2SO4 and CaCl2 resulted in extended vase life at 1.0 dS·m–1, but increasing salt levels decreased overall vase life. As EC increased, regardless of salt type, water uptake also increased up to a maximum at 0.5 or 1.0 dS·m–1 and then continually declined. Maximum vase life was observed at 1.5 dS·m–1 for cut ‘Charlotte’ stems, and at 1.0 dS·m–1 for ‘Classy’ with the addition of a holding solution. Physiological effects were different based on cultivar, as observed with Charlotte and Freedom flowers that opened further and had less petal browning than Classy flowers. ‘Freedom’ had the greatest pigment loss, but this effect decreased with increasing EC. Further correlational analysis showed that in water-only solutions, initial and final EC accounted for 44% and 41% of the variation in vase life data, respectively, whereas initial pH accounted for 24% of variation. However, the presence of carbohydrates and biocides from the holding solution was found to have a greater effect on overall vase life compared with water pH or EC. Finally, in Expts. 5 and 6, cut ‘Freedom’ stems were subjected to DW solutions containing 0.1, 1, 10, or 100 mg·L–1 boron, copper, iron, potassium, magnesium, manganese, or zinc. None of these solutions increased vase life. Conversely, 10 or 100 mg·L–1 boron and 100 mg·L–1 copper solutions reduced vase life. Finally, the addition of NaCl to a maximum of 0.83 dS·m–1 increased the vase life in all solutions. These analyses highlight the importance of water quality and its elemental constituents on the vase life of cut rose stems and that the use of a holding solution can overcome the negative effects of high EC water.


2021 ◽  
Vol 12 ◽  
Author(s):  
Gary P. Latham ◽  
Guy Itzchakov

Four experiments were conducted to determine whether participants' awareness of the performance criterion on which they were being evaluated results in higher scores on a criterion valid situational interview (SI) where each question either contains or does not contain a dilemma. In the first experiment there was no significant difference between those who were or were not informed of the performance criterion that the SI questions predicted. Experiment 2 replicated this finding. In each instance the SI questions in these two experiments contained a dilemma. In a third experiment, participants were randomly assigned to a 2 (knowledge/no knowledge provided of the criterion) X 2 (SI dilemma/no dilemma) design. Knowledge of the criterion increased interview scores only when the questions did not contain a dilemma. The fourth experiment revealed that including a dilemma in a SI question attenuates the ATIC-SI relationship when participants must identify rather than be informed of the performance criterion that the SI has been developed to assess.


Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3794
Author(s):  
Filippo Piccinini ◽  
Giovanni Martinelli ◽  
Antonella Carbonaro

During the COVID-19 pandemic, there has been a significant increase in the use of non-contact infrared devices for screening the body temperatures of people at the entrances of hospitals, airports, train stations, churches, schools, shops, sports centres, offices, and public places in general. The strong correlation between a high body temperature and SARS-CoV-2 infection has motivated the governments of several countries to restrict access to public indoor places simply based on a person’s body temperature. Negating/allowing entrance to a public place can have a strong impact on people. For example, a cancer patient could be refused access to a cancer centre because of an incorrect high temperature measurement. On the other hand, underestimating an individual’s body temperature may allow infected patients to enter indoor public places where it is much easier for the virus to spread to other people. Accordingly, during the COVID-19 pandemic, the reliability of body temperature measurements has become fundamental. In particular, a debated issue is the reliability of remote temperature measurements, especially when these are aimed at identifying in a quick and reliable way infected subjects. Working distance, body–device angle, and light conditions and many other metrological and subjective issues significantly affect the data acquired via common contactless infrared point thermometers, making the acquisition of reliable measurements at the entrance to public places a challenging task. The main objective of this work is to sensitize the community to the typical incorrect uses of infrared point thermometers, as well as the resulting drifts in measurements of body temperature. Using several commercial contactless infrared point thermometers, we performed four different experiments to simulate common scenarios in a triage emergency room. In the first experiment, we acquired several measurements for each thermometer without measuring the working distance or angle of inclination to show that, for some instruments, the values obtained can differ by 1 °C. In the second and third experiments, we analysed the impacts of the working distance and angle of inclination of the thermometers, respectively, to prove that only a few cm/degrees can cause drifts higher than 1 °C. Finally, in the fourth experiment, we showed that the light in the environment can also cause changes in temperature up to 0.5 °C. Ultimately, in this study, we quantitatively demonstrated that the working distance, angle of inclination, and light conditions can strongly impact temperature measurements, which could invalidate the screening results.


Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 867
Author(s):  
John P. Thompson ◽  
Timothy G. Clewett

In two experiments on a farm practicing conservation agriculture, the grain yield of a range of wheat cultivars was significantly (p < 0.001) negatively related to the post-harvest population densities of Pratylenchus thornei in the soil profile to 45 cm depth. In a third and fourth experiment with different rotations, methyl bromide fumigation significantly (p < 0.05) decreased (a) a low initial population density of P. thornei in the soil profile to 90 cm depth and (b) a high initial population of P. thornei to 45 cm depth, and a medium level of the crown rot fungus, Fusarium pseudograminearum, at 0–15 cm depth to a low level. For a range of wheat and durum cultivars, grain yield and response to fumigation were highly significantly (p < 0.001) related to (a) the P. thornei tolerance index of the cultivars in the third experiment, and (b) to both the P. thornei tolerance index and the crown rot resistance index in the fourth experiment. In the latter, grain yield was significantly (p < 0.001) positively related to biomass at anthesis and negatively related to percentage whiteheads at grain fill growth stage. One barley cultivar was more tolerant to both diseases than the wheat and durum cultivars. Crop rotation, utilizing crop cultivars resistant and tolerant to both P. thornei and F. pseudograminearum, is key to success for conservation farming in this region.


2021 ◽  
Vol 22 (1) ◽  
pp. 104-118
Author(s):  
R. I. Shangaraev ◽  
M. H. Lutfullin ◽  
R. R. Timerbayeva ◽  
R. R. Guizzatullin ◽  
R. R. Gizzatullina

The parameters of acute toxicity of azomethine "C-18" and blood indicatorsin young cattle, naturally invaded by nematodiruses before and after treatment with this remedyand various anti-helmintic drugs, were studied. The therapeutic dose of azomethine in calvesaffected with nematodirosis was titrated. In the first experiment, the acute toxicity of azomethine "С-18" was studied in white outbred mice and rats. As the result of the studies, the average death dose of azomethine "С-18" was not established. The maximum dose administered was 2000 mg/kg. There was nolossin laboratory animals. In the second experiment, the effect of azomethine "С-18" on the blood indicators of helminth-infested cattle was investigated. It was established that in the blood of calves naturally infected with nematodiruses there were: erythropenia, hypohemoglobinemia, leukocytosis, eosinophilia, lymphocytopenia, giproteinemia, hypoglycemia, increased transaminase activity. After deworming these animals withtetramizole granulate, 10% albendazole suspension and azomethine "С-18" broken hematological parameters were completely restored up to physiological norm on the 30-th day. In the third experiment, the effect of different doses of azomethine "С-18" on the hematological indices of healthy cattle were studied. The animals were orally administered azomethine "С-18" in doses of 50.0 and 100.0 mg/kg. After that hypoglycemia, increased alkaline phosphatase activity and reduced urea content were found in serum ofcalves. In the fourth experiment, the anthelmintic efficacy of various doses of azomethine "С-18" in cattle affected with nematodirosiswas studied. It has been established that azomethine "С-18" in doses 2; 5; 10; 15 and 20 mg/kg showed approximately the sameintensity of efficacy, which ranged from 95.3 to 97.9%. The extensity of efficacywas 87.5%. The therapeutic dose was 2.0 mg/kg.


2021 ◽  
pp. 174702182098614
Author(s):  
Ivan I Ivanchei ◽  
Senne Braem ◽  
Luc Vermeylen ◽  
Wim Notebaert

Recent studies have demonstrated that cognitive conflict, as experienced during incongruent Stroop trials, is automatically evaluated as negative in line with theories emphasising the aversive nature of conflict. However, while this is well replicated when people only see the conflict stimuli, results are mixed when participants also respond to stimuli before evaluating them. Potentially, the positive surprise people feel when overcoming the conflict allows them to evaluate the experience as more positive. In this study, we investigated whether task experience can account for contradictory findings in the literature. Across three experiments, we observed that responding to incongruent stimuli was evaluated as negative on the first trials, but this effect disappeared after 32 trials. This contrasted with the results of a fourth experiment showing that the negative evaluation of incongruent trials did not disappear, when participants could not respond to the conflict. A re-analysis of three older experiments corroborated these results by showing that a positive evaluation of conflict only occurred after participants had some experience with the task. These results show that responding to conflict clearly changes its affective evaluation fitting with the idea that creating outcome expectancies (lower expectancies for being correct on incongruent trials) makes the experience of conflict less negative.


2021 ◽  
Vol 7 ◽  
Author(s):  
Celso M. de Melo ◽  
Stacy Marsella ◽  
Jonathan Gratch

As autonomous machines, such as automated vehicles (AVs) and robots, become pervasive in society, they will inevitably face moral dilemmas where they must make decisions that risk injuring humans. However, prior research has framed these dilemmas in starkly simple terms, i.e., framing decisions as life and death and neglecting the influence of risk of injury to the involved parties on the outcome. Here, we focus on this gap and present experimental work that systematically studies the effect of risk of injury on the decisions people make in these dilemmas. In four experiments, participants were asked to program their AVs to either save five pedestrians, which we refer to as the utilitarian choice, or save the driver, which we refer to as the nonutilitarian choice. The results indicate that most participants made the utilitarian choice but that this choice was moderated in important ways by perceived risk to the driver and risk to the pedestrians. As a second contribution, we demonstrate the value of formulating AV moral dilemmas in a game-theoretic framework that considers the possible influence of others’ behavior. In the fourth experiment, we show that participants were more (less) likely to make the utilitarian choice, the more utilitarian (nonutilitarian) other drivers behaved; furthermore, unlike the game-theoretic prediction that decision-makers inevitably converge to nonutilitarianism, we found significant evidence of utilitarianism. We discuss theoretical implications for our understanding of human decision-making in moral dilemmas and practical guidelines for the design of autonomous machines that solve these dilemmas while, at the same time, being likely to be adopted in practice.


HortScience ◽  
2020 ◽  
Vol 55 (12) ◽  
pp. 1974-1979
Author(s):  
Uttara C. Samarakoon ◽  
James E. Faust

Clematis (Clematis ×hybrida) is among the flowering plants well-recognized by the retail consumer; however, production has not traditionally fit into standard greenhouse production systems. One reason is the relatively long 2-year production cycle from propagation to flowering. Four experiments were conducted with clematis ‘H.F. Young’ to understand the factors that influence shoot development and flowering of clematis so that strategies could be developed for bulking, providing a cold treatment, and flowering the plants with a shortened production time. The first experiment showed an increase in shoot and flower numbers and a decrease in time to flower as the duration of cold treatment increased from 0 to 9 weeks and the photoperiod increased from 9 to 16 hours. The second experiment resulted in greater shoot and flower numbers when plants were forced at 21 °C as compared with 27 °C. The third experiment showed that the application of ethephon (500 or 1000 mg·L−1) during bulking increased shoot formation (branching) as compared with the control or 500 mg·L−1 benzylaminopurine treatments. The fourth experiment showed that applications of 500 mg·L−1 ethephon along with a 16-hour photoperiod during the bulking period improved shoot number and flowering of the finished crop. The combined results provide guidelines for producing a well-branched, flowering clematis crop within 1 year from the start of propagation to the time of the first open flower.


Author(s):  
Yanfang Xia ◽  
Filip Melinscak ◽  
Dominik R. Bach

Abstract Threat-conditioned cues are thought to capture overt attention in a bottom-up process. Quantification of this phenomenon typically relies on cue competition paradigms. Here, we sought to exploit gaze patterns during exclusive presentation of a visual conditioned stimulus, in order to quantify human threat conditioning. To this end, we capitalized on a summary statistic of visual search during CS presentation, scanpath length. During a simple delayed threat conditioning paradigm with full-screen monochrome conditioned stimuli (CS), we observed shorter scanpath length during CS+ compared to CS- presentation. Retrodictive validity, i.e., effect size to distinguish CS+ and CS-, was maximized by considering a 2-s time window before US onset. Taking into account the shape of the scan speed response resulted in similar retrodictive validity. The mechanism underlying shorter scanpath length appeared to be longer fixation duration and more fixation on the screen center during CS+ relative to CS- presentation. These findings were replicated in a second experiment with similar setup, and further confirmed in a third experiment using full-screen patterns as CS. This experiment included an extinction session during which scanpath differences appeared to extinguish. In a fourth experiment with auditory CS and instruction to fixate screen center, no scanpath length differences were observed. In conclusion, our study suggests scanpath length as a visual search summary statistic, which may be used as complementary measure to quantify threat conditioning with retrodictive validity similar to that of skin conductance responses.


2020 ◽  
Vol 11 (2) ◽  
pp. 25
Author(s):  
Ahmad Yunus Nasution

In this modern era, the use of plastic is very much in the community, this alone makes the accumulation of plastic waste. And the nature of plastic waste has properties that are difficult to decompose and even need hundreds of years, this is also what makes the accumulation of plastic waste. Of the menabahnya amount of plastic such as plastic materials that can only be used and thrown for example are mineral water bottles, plastic bags or plastic food wrappers and This type of sterofoam waste is the most widely used and most piles of garbage collection.In my analysis process the plastic that will be processed using the pyrolysis method is rubbish whose category is plastic waste made from vinyl chloride, polyethylene, acrylic, silicone, urethane , which we can find most of its use as food packaging or household plastic appliances. Comparison of the first plastic garbage type of type 1: Polyethylene Terephthalate (PET or PETE or Polyester) and type 2: High Density Polyethylene (HDPE) , with the amount of plastic waste ratio of 1: 1. Comparison to two types of 1: Polyethylene Terephthalate (PET or PETE or Polyester) and type 4: Low Density Polyethylene (LDPE) , with a ratio of 1: 1 plastic waste. Comparison of all three types of 1 : Polyethylene Terephthalate (PET or PETE or Polyester) and type 6: Polystyrene (PS) , the amount of plastic waste ratio of 1: 1.Results from this study obtain data Data obtained from PET & HDPE experiments obtained oil and heat obtained from experiments 1 to 5. On The first experiment oil obtained was 0.15 Liters and Heat for evaporation of material was 2829.78 kJ. On The Second experiment oils obtained were 0.74 Liters and Heat for the evaporation of material 2829.78 kJ . On The third experiment oil obtained was 0.74 liters and heat for the evaporation of material 2829.78 kJ. On The Fourth experiment oils obtained were 0.74 Liters and Heat for the evaporation of material 2829.78 kJ . On The Fifth experiment oils obtained were 0.74 Liters and Heat for evaporation of the material 2829.78 Kj .Data obtained from PET & LDPE experiments obtained oil and heat obtained from experiments 1 to 5. On The First experiment oil obtained was 0.47 Liters and Heat for evaporation of 4119.3 kJ material . On The Second experiment oils obtained were 0.51 Liters and Heat for evaporation of 4334.22 kJ material . On The third experiment oil obtained was 0.36 liters and heat for evaporation of material 4226.76 kJ . On The Fourth experiment oils obtained were 0.44 Liters and Heat for evaporation of 5014.8 kJ material . On The Fifth experiment oils obtained were 0.5 Liters and Heat for the evaporation of ingredients 4477.5 Kj.


Sign in / Sign up

Export Citation Format

Share Document