Observations on the Luminescence of the Larval Glowworm, Lampyris noctiluca L. (Col. Lampyridae)

1974 ◽  
Vol 5 (2) ◽  
pp. 103-109 ◽  
Author(s):  
Hans Dreisig
Keyword(s):  
Adult Female ◽  
Full Moon ◽  
Late Summer ◽  
Active Period ◽  
Ambient Illumination ◽  
Experimental Conditions ◽  
Adult Females ◽  
The Difference

AbstractThe larval luminescence in L. noctiluca consists in a glow lasting for several seconds (average 7.3 sec.) emitted at irregular intervals while the animal is crawling about during the active period at night. In the adult female the glow is continuous often for several hours. Also some larvae in the last instar were able to glow continuously for hours. Onset of activity in the larvae occurred at a lower critical ambient illumination (6.85 log lux +10) than in adult females (10.10 log lux+10). The dispersion of onsets was greater in larvae than in females. The duration of luminescent activity in the field was ca. 5 hours and at experimental conditions ca. 8 hours. In thc field larvae were mostly seen during late summer, probably because of the low critical illumination, which was also the reason why activity was suspended on moonlit nights. The intensity of moonlight around full moon was ca. 8.00—9.00 log lux+10. In the discussion the following subjects are treated: The function of larval luminescence; the reaction of larvae to ambient illumination; and the difference between glowing and flashing.

scholarly journals Potential Pitfalls in Membrane Fouling Evaluation: Merits of Data Representation as Resistance Instead of Flux Decline in Membrane Filtration

Membranes ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 460
Author(s):  
Bastiaan Blankert ◽  
Bart Van der Bruggen ◽  
Amy E. Childress ◽  
Noreddine Ghaffour ◽  
Johannes S. Vrouwenvelder
Keyword(s):  
Membrane Fouling ◽  
Membrane Filtration ◽  
Data Representation ◽  
Strong Impact ◽  
Experimental Conditions ◽  
Permeable Membrane ◽  
Dead End ◽  
Flux Decline ◽  
The Difference ◽  
Filtration Flux

The manner in which membrane-fouling experiments are conducted and how fouling performance data are represented have a strong impact on both how the data are interpreted and on the conclusions that may be drawn. We provide a couple of examples to prove that it is possible to obtain misleading conclusions from commonly used representations of fouling data. Although the illustrative example revolves around dead-end ultrafiltration, the underlying principles are applicable to a wider range of membrane processes. When choosing the experimental conditions and how to represent fouling data, there are three main factors that should be considered: (I) the foulant mass is principally related to the filtered volume; (II) the filtration flux can exacerbate fouling effects (e.g., concentration polarization and cake compression); and (III) the practice of normalization, as in dividing by an initial value, disregards the difference in driving force and divides the fouling effect by different numbers. Thus, a bias may occur that favors the experimental condition with the lower filtration flux and the less-permeable membrane. It is recommended to: (I) avoid relative fouling performance indicators, such as relative flux decline (J/J0); (II) use resistance vs. specific volume; and (III) use flux-controlled experiments for fouling performance evaluation.

scholarly journals Validation of a Method Based on Triglycerides for the Detection of Low Percentages of Hazelnut Oil in Olive Oil by Column Liquid Chromatography

2007 ◽  
Vol 90 (5) ◽  
pp. 1346-1353 ◽  
Author(s):  
Diego L García-González ◽  
María Viera-Macías ◽  
Ramón Aparicio-Ruiz ◽  
Maria T Morales ◽  
Ramón Aparicio
Keyword(s):  
Liquid Chromatography ◽  
Olive Oil ◽  
Carbon Number ◽  
Hazelnut Oil ◽  
Equivalent Carbon Number ◽  
Experimental Conditions ◽  
Mathematical Algorithm ◽  
Relative Standard ◽  
Triglyceride Content ◽  
The Difference

Abstract The difference between theoretical and empirical triglyceride content is a powerful tool to detect the presence of any vegetable oil in olive oil. The current drawback of the method is the separation between equivalent carbon number ECN42 compounds, which affects the reliability of the method and, hence, its cutoff limit. The determination of the triglyceride profile by liquid chromatography using propionitrile as the mobile phase has recently been proposed to improve their quantification, together with a mathematical algorithm whose binary response determines the presence or absence of hazelnut oil. Twenty-one laboratories from 9 countries participated in an interlaboratory study to evaluate the performance characteristics of the whole analytical method. Participants analyzed 12 samples in duplicate, split into 3 intercomparison studies. Statistically significant differences due to the experimental conditions were found in some laboratories, which were detected as outliers by use of Cochran's and Grubbs' tests. The relative standard deviations (RSD) for repeatability and reproducibility were determined following the AOAC Guidelines for Collaborative Studies. The analytical properties of the method were determined by means of the sensitivity (0.86), selectivity (0.94), and reliability (72) for a cutoff limit of 8 (probability 94).

scholarly journals Alpha EEG Frontal Asymmetries during Audiovisual Perception in Cochlear Implant Users

2015 ◽  
Vol 54 (06) ◽  
pp. 500-504 ◽  
Author(s):  
A. G. Maglione ◽  
A. Scorpecci ◽  
P. Malerba ◽  
P. Marsella ◽  
S. Giannantonio ◽  
...  
Keyword(s):  
Cochlear Implant ◽  
Alpha Rhythm ◽  
Normal Hearing ◽  
Experimental Conditions ◽  
Audiovisual Perception ◽  
Audiovisual Stimuli ◽  
The Difference ◽  
Eeg Alpha ◽  
The One ◽  
Hearing Children

SummaryObjectives: The aim of the present study is to investigate the variations of the electroencephalographic (EEG) alpha rhythm in order to measure the appreciation of bilateral and unilateral young cochlear implant users during the observation of a musical cartoon. The cartoon has been modified for the generation of three experimental conditions: one with the original audio, another one with a distorted sound and, finally, a mute version.Methods: The EEG data have been recorded during the observation of the cartoons in the three experimental conditions. The frontal alpha EEG imbalance has been calculated as a measure of motivation and pleasantness to be compared across experimental populations and conditions.Results: The EEG frontal imbalance of the alpha rhythm showed significant variations during the perception of the different cartoons. In particular, the pattern of activation of normal-hearing children is very similar to the one elicited by the bilateral implanted patients. On the other hand, results related to the unilateral subjects do not present significant variations of the imbalance index across the three cartoons.Conclusion: The presented results suggest that the unilateral patients could not appreciate the difference in the audio format as well as bilaterally implanted and normal hearing subjects. The frontal alpha EEG imbalance is a useful tool to detect the differences in the appreciation of audiovisual stimuli in cochlear implant patients.

The effect of exposure to conspecifics on restlessness in the parasitoid wasp Nasonia vitripennis (Hymenoptera: Pteromalidae)

2007 ◽  
Vol 139 (5) ◽  
pp. 678-684 ◽  
Author(s):  
B.H. King
Keyword(s):  
Habitat Quality ◽  
Parasitoid Wasp ◽  
Poor Quality ◽  
The Other ◽  
Dispersal Ability ◽  
Nasonia Vitripennis ◽  
Adult Females ◽  
Selection For ◽  
The Difference ◽  
Abundance And Distribution

AbstractWhen habitat quality is variable, there should be strong selection for the ability to detect and respond to the variation. Adult females of the parasitoid wasp Nasonia vitripennis (Walker) are known to increase their restlessness (the proportion of time in locomotion) both during and after exposure to a poor quality host. Doing so provides a mechanism for leaving a poor host and potentially finding a better host. This study examined whether restlessness also changes in response to competition as indicated by the presence of adult conspecifics. Both restlessness and the probability of dispersing across an inhospitable environment were greater when a female was with another female than when she was alone. However, restlessness did not remain elevated after the other female was removed. In contrast with females, restlessness of males did not increase either during or after exposure to other males, and the probability of dispersing across an inhospitable environment was unaffected by the presence of another male. The difference between females and males may be related to differences in dispersal ability and in the abundance and distribution of hosts versus mates.

scholarly journals XXIII.—On the Disruptive Discharge of Electricity: An Experimental Thesis for the Degree of Doctor of Science, Department A

1878 ◽  
Vol 28 (2) ◽  
pp. 633-671 ◽  
Author(s):  
Alexander Macfarlane
Keyword(s):  
Copper Wire ◽  
Late Summer ◽  
The Other ◽  
Straight Line ◽  
Summer Session ◽  
The Difference ◽  
A Chain ◽  
The One ◽  
Metallic Parts ◽  
The University

The experiments to which I shall refer were carried out in the physical laboratory of the University during the late summer session. I was ably assisted in conducting the experiments by three students of the laboratory,—Messrs H. A. Salvesen, G. M. Connor, and D. E. Stewart. The method which was used of measuring the difference of potential required to produce a disruptive discharge of electricity under given conditions, is that described in a paper communicated to the Royal Society of Edinburgh in 1876 in the names of Mr J. A. Paton, M. A., and myself, and was suggested to me by Professor Tait as a means of attacking the experimental problems mentioned below.The above sketch which I took of the apparatus in situ may facilitate tha description of the method. The receiver of an air-pump, having a rod capable of being moved air-tight up and down through the neck, was attached to one of the conductors of a Holtz machine in such a manner that the conductor of the machine and the rod formed one conducting system. Projecting from the bottom of the receiver was a short metallic rod, forming one conductor with the metallic parts of the air-pump, and by means of a chain with the uninsulated conductor of the Holtz machine. Brass balls and discs of various sizes were made to order, capable of being screwed on to the ends of the rods. On the table, and at a distance of about six feet from the receiver, was a stand supporting two insulated brass balls, the one fixed, the other having one degree of freedom, viz., of moving in a straight line in the plane of the table. The fixed insulated ball A was made one conductor with the insulated conductor of the Holtz and the rod of the receiver, by means of a copper wire insulated with gutta percha, having one end stuck firmly into a hole in the collar of the receiver, and having the other fitted in between the glass stem and the hollow in the ball, by which it fitted on to the stem tightly. A thin wire similarly fitted in between the ball B and its insulating stem connected the ball with the insulated half ring of a divided ring reflecting electrometer.

scholarly journals Effects of Environmental Temperature onCapnodis tenebrionisAdult Phenology

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Carmelo Peter Bonsignore
Keyword(s):  
Late Summer ◽  
Early Summer ◽  
Adult Density ◽  
Degree Days ◽  
Continuous Increase ◽  
Climate Conditions ◽  
Average Annual Temperature ◽  
Activity Temperature ◽  
The Difference ◽  
New Generation

The phenology ofCapnodis tenebrionisadults was presented with reference to two different climate conditions. In a temperate moderate-warm climate, adult density showed two separate peaks during the year: one in early summer of the overwintering generation and one with beetles emerging in the late summer. In a warmer semiarid climate, the overwintering adults and the new generation overlapped during summer with a continuous increase of adult density. The difference in the average annual temperature between areas during the study period was almost3∘C, and, in the warmer area, the new generation ofC. tenebrionisemerged at least one month earlier. To make a prediction of adult presence, a model utilizing degree-days was developed from data collected over a five-year period. Models obtained from equations (Logistic 4-parameter,y(x)=yo+a/(1+(x/xo)b)) of each year were developed to describe the relationship between degree-day accumulation (with a minimal threshold activity temperature of14.21∘Ccalculated in the laboratory) and the cumulative percentage of adult presence. According to the overall model, the 50% of overwintering beetles occurred at 726 degree-days (Biofix: 1st March) and the emerging beetles occurred at 801 degree-days (Biofix: 1st July). The results show that a change in temperature is an important aspect that highlights the adaptability of this species.

The diffusion of 75Se(IV) in Beishan granite – temperature, oxygen condition and ionic strength effects

2018 ◽  
Vol 107 (1) ◽  
pp. 39-54
Author(s):  
Chunli Wang ◽  
Xiaoyu Yang ◽  
Jiangang He ◽  
Fangxin Wei ◽  
Zhong Zheng ◽  
...  
Keyword(s):  
Ionic Strength ◽  
Effective Diffusion ◽  
Aerobic Condition ◽  
Double Layers ◽  
Solution Viscosity ◽  
Formation Factor ◽  
Experimental Conditions ◽  
Beishan Granite ◽  
Oxygen Condition ◽  
The Difference

Abstract To explore the diffusion behavior of 75Se(IV) in Beishan granite (BsG), the influences of temperature, oxygen condition and ionic strength were investigated using the through-diffusion experimental method. The effective diffusion coefficient De of 75Se(IV) in BsG varied from 4.21×10−14 m2/s to 3.19×10−13 m2/s in our experimental conditions, increased with increasing temperature. The formation factor Ff of BsG was calculated to be nearly constant in the range of temperatures investigated, suggesting that the inner structure of BsG had no significant change in the temperature range of 20–55°C. Meanwhile, the De values of 75Se(IV) in BsG under anaerobic condition was significantly larger than that under aerobic condition, which may be attributed to the difference in the sorption characteristics and species distribution of Se and pH values. Moreover, the diffusion of 75Se(IV) was promoted with ionic strength increased from 0.01 M to 0.1 M, and then decreased at 0.5 M, mainly due to the combined effects of reduced double layers with increased ionic strength and increase of the solution viscosity at higher ionic strength.

scholarly journals Iodination of insulin in aqueous and organic solvents

1969 ◽  
Vol 115 (1) ◽  
pp. 11-18 ◽  
Author(s):  
A. Massaglia ◽  
U. Rosa ◽  
G. Rialdi ◽  
C. A. Rossi
Keyword(s):  
Ethylene Glycol ◽  
Organic Solvents ◽  
Molecular Conformation ◽  
Aqueous Media ◽  
Native Structure ◽  
Experimental Conditions ◽  
Polar Environment ◽  
Polar Area ◽  
The Difference ◽  
A Chain

1. The iodination of insulin was studied under various experimental conditions in aqueous media and in some organic solvents, by measuring separately the uptake of iodine by the four tyrosyl groups and the relative amounts of monoiodotyrosine and di-iodotyrosine that are formed. In aqueous media from pH1 to pH9 the iodination occurs predominantly on the tyrosyl groups of the A chain. Some organic solvents increase the iodine uptake of the B-chain tyrosyl groups. Their efficacy in promoting iodination of Tyr-B-16 and Tyr-B-26 is in the order: ethylene glycol and propylene glycol≃methanol and ethanol>dioxan>8m-urea. 2. It is suggested that each of the four tyrosyl groups in insulin has a different environment: Tyr-A-14 is fully exposed to the solvent; Tyr-A-19 is sterically influenced by the environmental structure, possibly by the vicinity of a disulphide interchain bond; Tyr-B-16 is embedded into a non-polar area whose stability is virtually independent of the molecular conformation; Tyr-B-26 is probably in a situation similar to Tyr-B-16 with the difference that its non-polar environment depends on the preservation of the native structure.

scholarly journals FEEDING AND REPRODUCTIVE ACTIVITY OF THE COPEPODS Drepanopus forcipatus AND Calanus australis DURING LATE SUMMER ON THE SOUTHERN PATAGONIAN SHELF (ARGENTINA, 47°-55°S)

2014 ◽  
Vol 62 (4) ◽  
pp. 295-314 ◽  
Author(s):  
Julieta Carolina Antacli ◽  
Marina E. Sabatini ◽  
Ricardo I. Silva ◽  
Daniel R. Hernández ◽  
Andrés J. Jaureguizar ◽  
...  
Keyword(s):  
Diet Composition ◽  
Feeding Activity ◽  
Food Pellet ◽  
Late Summer ◽  
Reproductive Activity ◽  
Seasonal Temperature ◽  
Patagonian Shelf ◽  
Adult Females ◽  
Female Reproductive Status ◽  
Potential Food

Drepanopus forcipatus and Calanus australis are key planktonic copepods on the southern Patagonian shelf. Their feeding and reproductive patterns and population status were investigated during late summer, when environmental conditions may be critical. The presence of food in the gut and food-pellet length were recorded in adult females and the most abundant copepodite stages. Diet composition was also studied in adult females. Female reproductive status was evaluated by gonad staging. Despite generally low feeding conditions and decreasing seasonal temperature, both copepods fed to some degree. The most numerous copepodites and adult females of both species showed similarly low feeding activity. About half of the adult females of the two species and C5s of C. australis contained food in their guts, but the proportion of fed C4-females of D. forcipatus was much lower. All copepods were generally feeding at low or intermediate levels. Gonad stage distribution and population structure showed low but still ongoing reproduction in both species. Gut content findings suggest a preference for smaller nanoplanktonic particles, especially dinoflagellates by D. forcipatus, and for autotrophic prey, particularly large diatoms by C. australis. The feeding and reproduction patterns of the two copepods were likely influenced by the distributions of potential food resources and temperature.

scholarly journals Impact of Modeling Simplifications on Lightning Strike Simulation for Aeroengine

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Yi-fan Qian ◽  
Zhi-feng Ye ◽  
Hai-bo Zhang
Keyword(s):  
Simulation Analysis ◽  
Simulation Software ◽  
Simplified Model ◽  
Lightning Strike ◽  
Electromagnetic Simulation ◽  
Experimental Conditions ◽  
Turbofan Engine ◽  
Engine Model ◽  
Simulation Results ◽  
The Difference

With the development of electromagnetic simulation software and affordable hardware, it is allowed for us to complete simulations for EMC purposes. However, simulation demands will be immense when simulations for models with complex structures, especially aircraft components, have to be solved. Hence, it is meaningful to investigate how to minimize the computational demands. One of the solutions to reduce the simulation expense is the simplification for the simulated model. But the simplified model should be guaranteed to provide credible simulation results which do not deviate from the original model apparently. Generally, the difference between the simulation results and experimental data is estimated, or if the experimental conditions are not achieved, the comparison between the simplified model and the original one has to be analyzed, at least. This paper explores the electromagnetic simulation of a turbofan engine encountering lightning strike. With the simplifications of different components on the turbofan engine, the influences on induced currents of engine controller cables are simulated and analyzed based on the transmission-line matrix method. A combining method of components removal and geometric structure simplification is proposed to simplify the whole engine model. Simplified components include compressor, combustion chamber, turbine, and nozzle. The effects of different simplification methods are quantified, and the rationality of the simplified model is verified by simulation analysis.

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