scholarly journals The Excretion and Storage of Ammonia by the Aquatic Larva of Sialis Lutaria (Neuroptera)

1955 ◽  
Vol 32 (1) ◽  
pp. 84-94
Author(s):  
B. W. STADDON
Keyword(s):  
The Body ◽  
Malpighian Tubules ◽  
Toxic Effects ◽  
Ammonia Content ◽  
Storage Mechanism ◽  
Total Ammonia ◽  
Wet Weight ◽  
Tissue Fluids ◽  
And Storage ◽  
Aquatic Larva

1. A study has been made of the excretion and storage of ammonia by the aquatic larva of Sialis lutaria. 2. About 90% of the nitrogen excreted by the larva of Sialis during starvation was in the form of ammonia. The daily ammonia output averaged 10 µg. N/100 mg. wet weight. 3. Ammonia was found to be excreted into the hindgut, presumably via the Malpighian tubules. The concentration of ammonia in the hindgut fluid averaged 136 mg. N/100 ml. 4. Evidence was obtained that the tissue fluids are not maintained completely ammonia-free. Thus the total ammonia content of the body averaged 1.0 µg. N/100 mg. wet weight of tissue. The concentration of ammonia in the haemolymph averaged 0.50 mg. N/100 ml. 5. Evidence was obtained that the larval tissues are capable of ‘storing’ appreciable quantities of ammonia. Thus ammonia did not accumulate in the tissue fluids of larvae prevented from excreting for a period of days. Furthermore, it was found experimentally possible to raise the concentration of ammonia in the tissue fluids, the ammonia subsequently disappearing. The possible significance of this ‘storage’ mechanism was discussed. 6. The method used for raising the concentration of ammonia in the tissue fluids, by immersing the larva for some time in a solution of dilute ammonia, was considered in some detail, particularly with respect to toxic effects. When the concentration of ammonia in the haemolymph had reached a level in the region of 7.0 mg. N/100 ml. toxic symptoms started to appear.

scholarly journals Migration of Silver and Copper Nanoparticles from Food Coating

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 380
Author(s):  
Hamed Ahari ◽  
Leila Khoshboui Lahijani
Keyword(s):  
Copper Nanoparticles ◽  
Inductively Coupled Plasma ◽  
Food Packaging ◽  
Human Life ◽  
Analytical Techniques ◽  
Optical Emission ◽  
Atomic Emission ◽  
The Body ◽  
Toxic Effects ◽  
Inductively Coupled

Packaging containing nanoparticles (NPs) can increase the shelf life of products, but the presence of NPs may hazards human life. In this regard, there are reports regarding the side effect and cytotoxicity of nanoparticles. The main aim of this research was to study the migration of silver and copper nanoparticles from the packaging to the food matrix as well as the assessment techniques. The diffusion and migration of nanoparticles can be analyzed by analytical techniques including atomic absorption, inductively coupled plasma mass spectrometry, inductively coupled plasma atomic emission, and inductively coupled plasma optical emission spectroscopy, as well as X-ray diffraction, spectroscopy, migration, and titration. Inductively coupled plasma-based techniques demonstrated the best results. Reports indicated that studies on the migration of Ag/Cu nanoparticles do not agree with each other, but almost all studies agree that the migration of these nanoparticles is higher in acidic environments. There are widespread ambiguities about the mechanism of nanoparticle toxicity, so understanding these nanoparticles and their toxic effects are essential. Nanomaterials that enter the body in a variety of ways can be distributed throughout the body and damage human cells by altering mitochondrial function, producing reactive oxygen, and increasing membrane permeability, leading to toxic effects and chronic disease. Therefore, more research needs to be done on the development of food packaging coatings with consideration given to the main parameters affecting nanoparticles migration.

Memoirs: Peristalsis in the Malpighian Tubules of Diptera, Preliminary Account: with a note on the Elimination of Calcium Carbonate from the Malpighian Tubules of Drosophila Funebris

1925 ◽  
Vol s2-69 (275) ◽  
pp. 385-398
Author(s):  
L. EASTHAM
Keyword(s):  
Calcium Carbonate ◽  
Basement Membrane ◽  
Longitudinal Muscle ◽  
The Body ◽  
Malpighian Tubules ◽  
Preliminary Account ◽  
Longitudinal Muscles ◽  
Adult Drosophila

1. The proximal regions of the Malpighian tubules of Drosopbila funebris and Calliphora erythro cephala are supplied with systems of circular and longitudinal muscles external to the basement membrane. 2. These muscles are continuous with those of the mid-gut. 3. There is a terminal muscle to each anterior tubule in Drosophila funebris connected to the alar muscles of the pericardial septum. 4. Peristalsis has been observed in the proximal regions of the tubules, caused by the circular muscles. 5. The tubules exhibit a waving movement, probably due to the longitudinal muscle-bands of the lower or proximal ends of the tubules. 6. Calcium carbonate is stored in the terminal portions of the anterior tubules of Drosophila funebris. 7. This calcium carbonate is not eliminated at the beginning of metamorphosis, but is passed to the gut about the sixth day of pupal life, and is only expelled from the body on the emergence of the adult. 8. Calcium carbonate is found in the Malpighian tubules of the adult Drosophila funebris.

The Permeability and Structure of the Cuticle of the Aquatic Larva of Sialis Lutaria

1955 ◽  
Vol 32 (2) ◽  
pp. 330-352 ◽  
Author(s):  
J. SHAW
Keyword(s):  
Body Weight ◽  
Critical Temperature ◽  
Heavy Water ◽  
Sudden Change ◽  
Indirect Evidence ◽  
The Body ◽  
Permeability Constant ◽  
Water Influx ◽  
Terrestrial Insects ◽  
Aquatic Larva

1. The permeability to water of the cuticle of Sialis larvae has been measured, using heavy water as tracer. The penetration was slow, the permeability constant being only 1.8 x 10-2 cm./hr. at 20° C. There was no obvious difference between the rate of water influx and outflux. The rate at which water penetrated into the tissues from the blood was much greater than through the cuticle. The Q10 for diffusion through the body surface was high, lying between 3.0 and 3.8. The osmotic uptake of water was calculated to be about 1% of the body weight per day at 10° C. 2. Drinking of water did not occur in normal larvae, but in larvae with the blood volume reduced, osmotic uptake of water through the gut did take place and the gut wall was much more permeable to water than the cuticle. A similar intake of water probably occurred during moulting. 3. The permeability of the cuticle to chloride was measured and also found to be of a low order (P = 1.04 x 10-4 cm./hr. at 17° C.). Sodium diffused out of the larva at the same rate as the chloride. 4. Histological examination of the cuticle showed that in the abdomen it was thin and consisted of a 7µ. thick endocuticle and a 1 µ epicuticle. Over the thorax it was thicker, and a polyphenol layer was present as the outer layer of the epicuticle. There was indirect evidence of the presence of a wax layer. 5. Wax was extracted from the cuticle, and the thickness of the layer from which it was derived was estimated by means of a monolayer technique. In the cuticle of the abdomen and gills the thickness averaged 0.1 µ. 6. The permeability to water of the cuticle was compared with that of terrestrial insects and was found to be much greater. This difference was not due to the thickness of the wax layer but probably to some physical properties of the wax. The cuticle of Sialis larvae showed no ‘critical temperature’ or sudden change in the permeability properties with temperature over the range of temperatures studied.

scholarly journals Comparison of working memory and sensory profile in boys and girls with writing disability

2019 ◽  
Vol 21 (4) ◽  
pp. 163-168
Author(s):  
Alireza Sangani ◽  
Paria Jangi
Keyword(s):  
Working Memory ◽  
Auditory Processing ◽  
Physical State ◽  
Multisensory Processing ◽  
The Body ◽  
Body Motion ◽  
Sensory Profile ◽  
Statistical Population ◽  
Significant Difference ◽  
And Storage

Background and aims: The main problems of children with learning disabilities are in cognition and their sensations. This study aimed to investigate the comparison of working memory and sensory profile in boys and girls with writing disability. Methods: The methodology of this descriptive study was the comparative type. The statistical population of this study was all girls and boys by the age of 8-10 suffering from the writing disability in Gorgan City during treatment in a writing disability center in summer of 2018. According to the research method, the stratified random sampling method was used and 50 boys and 58 girls were selected from each group. According to research tools, the Dunn profile (1999) was obtained from the parents of the children. In the area of Daneman, & Carpenter working memory (1980), questions were asked from the children directly, and the information related to processing and storage in their memory were received. Data were analyzed using multivariate analysis of variance analysis using SPSS24 software. Results: Descriptive findings showed that mean and standard deviation in boys and girls were respectively in Processing (50.32±6.93, 54.22±7.45), Storage (48.47±6.08, 53.17±6.07), Indoctrination associated with the physical state of the body motion (34.28±7.09, 36.91±6.48), Multisensory processing (34.68±5.21, 37.94±6.57), Auditory Processing (31.74±5.84, 35.52±6.59). Also the results indicate that there is a significant difference in the writing disability among processing (P<0.006) and storage (P<0.000) of working memory subscales and the Indoctrination associated with the physical state of the body motion (P<0.000), Multisensory processing (P<0.000) and Auditory Processing (P<0.002), of the sensory profile variable in both the girls and boys with writing disability. Conclusion: with regard to the results obtained, it can be concluded that the boys group is in worse conditions in working memory and sensory processing styles, which requires a special attention and more focused educational approaches.

scholarly journals Potential Toxicity of Iron Oxide Magnetic Nanoparticles: A Review

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3159 ◽  
Author(s):  
Nemi Malhotra ◽  
Jiann-Shing Lee ◽  
Rhenz Alfred D. Liman ◽  
Johnsy Margotte S. Ruallo ◽  
Oliver B. Villaflores ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Cell Lines ◽  
Current Knowledge ◽  
Volume Ratio ◽  
The Body ◽  
Toxic Effects ◽  
Iron Oxide Magnetic Nanoparticles

The noteworthy intensification in the development of nanotechnology has led to the development of various types of nanoparticles. The diverse applications of these nanoparticles make them desirable candidate for areas such as drug delivery, coasmetics, medicine, electronics, and contrast agents for magnetic resonance imaging (MRI) and so on. Iron oxide magnetic nanoparticles are a branch of nanoparticles which is specifically being considered as a contrast agent for MRI as well as targeted drug delivery vehicles, angiogenic therapy and chemotherapy as small size gives them advantage to travel intravascular or intracavity actively for drug delivery. Besides the mentioned advantages, the toxicity of the iron oxide magnetic nanoparticles is still less explored. For in vivo applications magnetic nanoparticles should be nontoxic and compatible with the body fluids. These particles tend to degrade in the body hence there is a need to understand the toxicity of the particles as whole and degraded products interacting within the body. Some nanoparticles have demonstrated toxic effects such inflammation, ulceration, and decreases in growth rate, decline in viability and triggering of neurobehavioral alterations in plants and cell lines as well as in animal models. The cause of nanoparticles’ toxicity is attributed to their specific characteristics of great surface to volume ratio, chemical composition, size, and dosage, retention in body, immunogenicity, organ specific toxicity, breakdown and elimination from the body. In the current review paper, we aim to sum up the current knowledge on the toxic effects of different magnetic nanoparticles on cell lines, marine organisms and rodents. We believe that the comprehensive data can provide significant study parameters and recent developments in the field. Thereafter, collecting profound knowledge on the background of the subject matter, will contribute to drive research in this field in a new sustainable direction.

scholarly journals Evidence for benthic body size miniaturization in the deep sea

2006 ◽  
Vol 86 (6) ◽  
pp. 1339-1345 ◽  
Author(s):  
Janne I. Kaariainen ◽  
Brian J. Bett
Keyword(s):  
Body Size ◽  
Deep Sea ◽  
Size Structure ◽  
Size Class ◽  
The Body ◽  
Significant Shift ◽  
Individual Biomass ◽  
Wet Weight ◽  
Accumulation Curves ◽  
Average Individual

The benthic body size miniaturization hypothesis states that deep-sea communities are dominated by organisms of smaller body size, although some field studies have produced contradictory results. Using appropriate sample sets, this study tests this hypothesis by contrasting the benthic communities of the Fladen Ground (North Sea, 150 m) and the Faroe–Shetland Channel (1600 m). Samples were collected for large (500 μm) and small macrofauna (250–355 μm), meiofauna (45 μm) as well as an intermediate sized ‘mesofauna’ (180 μm) to ensure comprehensive coverage of the full meio- and macro-faunal body size-range. The body size structure of the benthos was compared using two methods. The more widely used average individual biomass method involves dividing the total sample biomass by sample abundance. Additionally, body size accumulation curves were constructed by assigning all specimens into a logarithmic size-class and then plotting the cumulative percentage of individuals present in each size-class. The results seem to support the hypothesis that the deep-sea environment is a small organism habitat. Although these findings only represent two locations, the overall body size accumulation curves clearly display a statistically significant shift towards smaller body sizes at the deeper site. The magnitude of the effect is appreciable with median metazoan body size reducing from 14.3 μg wet weight in the Fladen Ground to 3.8 μg wet weight in the Faroe–Shetland Channel. The average individual biomass measurements are shown to be of limited value and can lead to potentially misleading conclusions if the underlying size structure is not analysed in detail.

Ammonia production during clot retraction and its use in assay of fibrinoligase.

1977 ◽  
Vol 23 (9) ◽  
pp. 1739-1743 ◽  
Author(s):  
S Mousli ◽  
N W Wakid
Keyword(s):  
Direct Method ◽  
Limiting Factor ◽  
Fibrinogen Concentration ◽  
Ammonia Production ◽  
Clot Retraction ◽  
Ammonia Content ◽  
Shed Blood ◽  
Cross Linkage ◽  
Total Ammonia

Abstract Clotting of recalcified plasma is followed by an increase in its ammonia content that lasts 4 to 6 h. This ammonia production closely parallels the increase in acid-insoluble fibrin, which is evidence that the ammonia results from the action of fibrinoligase. If the clot is removed, ammonia production stops. The initial velocity of ammonia production is directly proportional to the fibrinogen concentration in plasma. Thus the rate-limiting factor in normal shed blood is the fibrinogen concentration. A maximum of 6.4 +/- 1.5 (SD) molecules of ammonia are produced per molecule of fibrinogen. Determination of the total ammonia produced is the fastest direct method of estimating the extent of frbrin cross-linkage in whole plasma. A method is proposed for assaying fibrinoligase, based on the rate of ammonia production in the presence of casein as substrate. Normal values are 7.6 +/- 2.9 (SD) mumol/min per liter of plasma.

Experiment and DFT studies on radioiodine removal and storage mechanism by imidazolium-based ionic liquid

2016 ◽  
Vol 64 ◽  
pp. 51-59 ◽  
Author(s):  
Bobo Cao ◽  
Shuangyue Liu ◽  
Dongmei Du ◽  
Zhimin Xue ◽  
Hui Fu ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Dft Studies ◽  
Storage Mechanism ◽  
And Storage
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