The fine structure of the PD proprioceptor of Cancer pagurus II. The position sensitive cells

1973 ◽  
Vol 184 (1075) ◽  
pp. 199-205 ◽  
Keyword(s):  
Fine Structure ◽  
Ventral Side ◽  
The Other ◽  
Maximum Sensitivity ◽  
Narrow Neck ◽  
Cancer Pagurus ◽  
Canal Cell ◽  
Position Sensitive ◽  
Physiological Differences ◽  
Different Levels

The cell bodies of the position sensitive units form a row distal to the movement sensitive cells and their dendrites run in pairs in a narrow neck of tissue on the ventral side of the receptor strand. The scolopidia share the features of elongation and relaxation sensitive movement units. Thus the canal cell is absent, but there is some scolopale material in the enveloping cells. Also the scolopale is apposed by a mixture of strand cells and collagen. The more distal scolopidia are found in a region of large haemocoelic lacunae. The physiological differences between movement and position sensitive units could be explained in terms of how well the dendrites are anchored into the tube; with the position cells possibly being held at different levels with respect to their maximum sensitivity. On the other hand, the dendrites of both types of unit may behave identically and, if so, then the necessary physiological differences could occur in the transduction and/or impulse initiation sites. These alternative explanations are discussed.

The fine structure of the PD proprioceptor of Cancer pagurus . I. The receptor stand and the movement sensitive cells

1973 ◽  
Vol 184 (1075) ◽  
pp. 179-197 ◽  
Keyword(s):  
Fine Structure ◽  
Dorsal Surface ◽  
Large Cell ◽  
Sensory Cells ◽  
Extracellular Material ◽  
Collagen Fibres ◽  
Cancer Pagurus ◽  
Canal Cell ◽  
Cellular Contact ◽  
Position Sensitive

The propodite-dactylopodite (PD) proprioceptor of Cancer pagurus consists of a receptor strand in which are embedded the dendrites of up to 80 bipolar nerve cells. The strand is composed of numerous cells and collagen and is surrounded by a thin layer of amorphous connective tissue. Beneath the latter there are often haemocoelic lacunae and individual haemocytes are found surrounded by strand tissue. The sensory cells can be divided into a proximal group with large cell bodies (movement sensitive cells) and a distal row with smaller cell bodies (position sensitive cells). The former can be further divided on the basis of the insertion of their dendrites into the strand. Thus elongation sensitive movement cells (e. s. m. cs) insert into the anterior surface and run in the ventral region of the receptor strand, while relaxation sensitive movement cells (r. s. m. cs) insert into the dorsal surface and run dorsally through the strand. The dendrites run in pairs, the members of each pair being either e. s. m. cs or r. s. m. cs. Each pair is surrounded distally by a scolopidium, consisting of a scolopale cell, two enveloping cells, a tube of extracellular material and, in e. s. m. cs, a canal cell. The scolopale cell contains a scolopale consisting of electron dense material laid down around a matrix of longitudinally oriented microtubules. In e. s. m. cs the enveloping cells also contain aggregations of a similar material. The dendrites make desmosome contacts with the scolopale cell and the corresponding thickenings of the scolopale cell membrane are juxtaposed by scolopale material. Beyond the scolopale the dendrites enter and terminate within a tube of extracellular material. In e. s. m. cs the scolopidium is surrounded mainly by strand cells, but in r. s. m. cs it is surrounded by collagen fibres. Where the collagen fibres meet the sheathing cells there are often contact zones. Other differences between e. s. m. cs and r. s. m. cs occur in the fine structure of the dendrites and these are described. It is suggested that in e. s. m. cs, since the scolopale is apposed by strand cells, stretching of the strand will lead to elongation of the scolopale and hence of the dendritic terminals. In contrast, in r. s. m. cs, it is possible that the scolopidium is not stretched during elongation of the strand, since there is little cellular contact between the two, but that during strand relaxation the energy stored in the collagen fibres forces the proximal end of the scolopale away from the more distal regions and hence stretches the dendritic terminations. Previous theories are discussed and compared with this idea. Also the relative merits of mechanical and physiological explanations for the phasic nature of these units are discussed.

Ultrastructure and Staining of Developing Elastic Tissue

1971 ◽  
Vol 29 ◽  
pp. 244-245
Author(s):  
E. N. Albert
Keyword(s):  
Fine Structure ◽  
Phosphotungstic Acid ◽  
Staining Method ◽  
Rat Aorta ◽  
Uranyl Acetate ◽  
The Other ◽  
Elastic Fibers ◽  
Elastic Tissue ◽  
Lead Citrate ◽  
New Born

Silver tetraphenylporphine sulfonate (Ag-TPPS) was synthesized in this laboratory and used as an electron dense stain for elastic tissue (Fig 1). The procedures for the synthesis of tetraphenylporphine sulfonate and the staining method for mature elastic tissue have been described previously.The fine structure of developing elastic tissue was observed in fetal and new born rat aorta using tetraphenylporphine sulfonate, phosphotungstic acid, uranyl acetate and lead citrate. The newly forming elastica consisted of two morphologically distinct components. These were a central amorphous and a peripheral fibrous. The ratio of the central amorphous and the peripheral fibrillar portion changed in favor of the former with increasing age.It was also observed that the staining properties of the two components were entirely different. The peripheral fibrous component stained with uranyl acetate and/or lead citrate while the central amorphous portion demonstrated no affinity for these stains. On the other hand, the central amorphous portion of developing elastic fibers stained vigorously with silver tetraphenylporphine sulfonate, while the fibrillar part did not (compare figs 2, 3, 4). Based upon the above observations it is proposed that developing elastica consists of two components that are morphologically and chemically different.

Further Studies on the Ultrastructure of Harderian Gland in Adult Rats

1974 ◽  
Vol 32 ◽  
pp. 288-289
Author(s):  
Alfredo Feria-Velasco ◽  
Guadalupe Tapia-Arizmendi
Keyword(s):  
Fine Structure ◽  
Domestic Fowl ◽  
Animal Species ◽  
Acinar Cells ◽  
Harderian Gland ◽  
Myoepithelial Cells ◽  
The Other ◽  
Albino Rats ◽  
Adult Rats ◽  
Cell Components

The fine structure of the Harderian gland has been described in some animal species (hamster, rabbit, mouse, domestic fowl and albino rats). There are only two reports in the literature dealing on the ultrastructure of rat Harderian gland in adult animals. In one of them the author describes the myoepithelial cells in methacrylate-embbeded tissue, and the other deals with the maturation of the acinar cells and the formation of the secretory droplets. The aim of the present work is to analize the relationships among the acinar cell components and to describe the two types of cells located at the perifery of the acini.

Effect of Catfish Bone Paste on the Properties of Steamed Bread

2014 ◽  
Vol 881-883 ◽  
pp. 757-760
Author(s):  
Xiao Qing Ren ◽  
Li Zhen Ma ◽  
Xin Yi He
Keyword(s):  
Weight Loss ◽  
Specific Volume ◽  
Cell Structure ◽  
The Other ◽  
Gas Cell ◽  
A Value ◽  
Crumb Structure ◽  
Steamed Bread ◽  
Different Levels ◽  
Structure Properties

The objective of this study was to examine the effect of different levels of catfish bone paste to flour on the physicochemical, textural and crumb structure properties of steamed bread. Six different levels (0, 1, 3, 5, 7,10 %) of catfish bone paste to flour were used in the formulation of the steamed bread. The results showed that the weight loss and TTA of steamed bread decreased with an increase in the levels of the catfish bone paste. On the other hand, the pH increased with an increase in the levels of the catfish bone paste. The specific volume, hardness, chewiness and gas cell structure in the crumb of steamed bread with catfish bone paste at 5% supplementation level were better. Thus, a value of 5% catfish bone paste was considered a better level for incorporation into the steamed bread.

scholarly journals Interferential comparison of the red and other radiations emitted by a new cadmium lamp and the michelson lamp

1933 ◽  
Vol 139 (837) ◽  
pp. 202-218 ◽  
Keyword(s):  
Fine Structure ◽  
High Temperature ◽  
Wave Length ◽  
The Other ◽  
Reference Standard ◽  
Definite Evidence ◽  
Electro Magnetic ◽  
The Many ◽  
Red Radiation ◽  
Red Line

It is now generally recognised that future definitions of the units of length will probably be based on the length of a wave of visible light. At present the wave-length of the red radiation of cadmium serves as the basis of all measurements of the lengths of electro-magnetic waves which are perceptible by optical means, and provisional sanction has been given to measurements of length on the same basis, as an alternative to direct reference to the metre. Whether the cadmium red radiation provides the best reference standard for all measurements of length has not yet been definitely established. Two international committees, one representing spectroscopists and the other metrologists, have sanctioned standard specifications for cadmium lamps of the Michelson type from which the red radiation may be produced. The two specifications differ from one another in certain details, but both are subject to the same objections. These objections are directed partly against the high temperature at which it is necessary to run the lamp and partly against the high voltage required to excite the radiation. Therefore, such hyperfine structure and asymmetry as may be present in the red line of cadmium is likely to be masked in the Michelson lamp by a combination of two phenomena —the enhanced Doppler effect due to the high temperature of the radiating cadmium atoms, and the effect of the moderately high intensity of the electric field. Were this not so, it might be somewhat surprising that no definite evidence of fine structure or asymmetry had so far been observed in the red line from the Michelson lamp, notwithstanding the many careful examinations, with the aid of the most sensitive interferometers, to which this line has been subjected, in view of its importance as the reference standard for all other wave-lengths. Recently Nagaoka and Sugiura have recorded that they have observed slight evidences of structure in the red radiation when excited under special conditions in which great precautions were taken to ensure extreme sharpness of the line. It is believed, however, that no subsequent confirmation of this effect has yet been published.

Distinction between Dolus and Culpa with reference to Arson in Zakon Sudnyj LJudem, the Vinodol Law and the Statute of Senj

De Jure ◽  
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Daniel Haman ◽  
◽  
◽  
Keyword(s):  
Criminal Law ◽  
The Other ◽  
Legal Documents ◽  
The Third ◽  
Other Hand ◽  
Criminal Offenses ◽  
The World ◽  
The Difference ◽  
Different Levels ◽  
Better Than

The difference between intent (dolus) and negligence (culpa) was rarely emphasized in codified medieval laws and regulations. When compared to the legal statements related to intent, negligence was mentioned even more rarely. However, there are some laws that distinguished between the two concepts in terms of some specific crimes, such as arson. This paper draws attention to three medieval Slavic legal documents – the Zakon Sudnyj LJudem (ZSLJ), the Vinodol Law and the Statute of Senj. They are compared with reference to regulations regarding arson, with the focus being on arson as a crime committed intentionally or out of negligence. The ZSLJ as the oldest known Slavic law in the world shows some similarities with other medieval Slavic legal codes, especially in the field of criminal law, since most of the ZSLJ’s articles are related to criminal law. On the other hand, the Vinodol Law is the oldest preserved Croatian law and it is among the oldest Slavic codes in the world. It was written in 1288 in the Croatian Glagolitic script and in the Croatian Chakavian dialect. The third document – the Statute of Senj – regulated legal matters in the Croatian littoral town of Senj. It was written in 1388 – exactly a century after the Vinodol Law was proclaimed. When comparing the Vinodol Law and the Statute of Senj with the Zakon Sudnyj LJudem, there are clear differences and similarities, particularly in the field of criminal law. Within the framework of criminal offenses, the act of arson is important for making a distinction between intent and negligence. While the ZSLJ regulates different levels of guilt, the Vinodol Law makes no difference between dolus and culpa. On the other hand, the Statute of Senj strictly refers to negligence as a punishable crime. Even though the ZSLJ is almost half a millennium older than the Statute of Senj and around 400 years older than the Vinodol Law, this paper proves that the ZSLJ defines the guilt and the punishment for arson much better than the other two laws.

scholarly journals Fine Structure and Staining Behaviour of Heterochromatic Segments in Two Plants

1974 ◽  
Vol 14 (3) ◽  
pp. 505-521
Author(s):  
L. F. LACOUR ◽  
B. WELLS
Keyword(s):  
Fine Structure ◽  
Light Microscope ◽  
Mitotic Cycle ◽  
The Other ◽  
Masking Effect ◽  
Root Tips ◽  
Metaphase Chromosomes ◽  
Differential Reactivity ◽  
Scilla Sibirica ◽  
Electron Microscopes

With the use of the light and electron microscopes, the chromosomes of Fritillaria lanceolata and Scilla sibirica are shown to differ in respect of the heterochromatin they contain. In root meristems of the former, the heterochromatic regions (H-segments) were recognizable at all phases of the mitotic cycle by their slighter opacity to electrons than that of euchromatic parts. This was due both to less tight packing of the chromatin fibrils and lower opacity of the fibrils themselves, even though both had the same diameter, about 3 nm. In root tips of the Scilla, the heterochromatin was invariably of similar opacity to euchromatin and thus only recognizable at telophase and interphase as large chromocentres. The opacity to electrons in the heterochromatin of the 2 species, was at all times closely paralleled by the staining behaviour seen with the light microscope in sections (0.07-0.5 µm in thickness) stained with toluidine blue. The disparity in the Fritillaria, as seen in sections with the light microscope, in respect of the stainability of the hetero- and euchromatin, was masked in Feulgen squash preparations of root tips from plants grown at 18-20 °C; at metaphase by the thickness of the chromosomes and at interphase by the density of the chromocentres. When, on the other hand, the plants were grown for 4 days at 2 °C, the masking effect of thickness was circumvented in metaphase chromosomes by differential super-contraction in euchromatin. The implications of these findings in respect to previous interpretations of the differential reactivity of H-segments to low temperature, as well as the phenomenon of enhanced and reduced fluorescence in these segments with fluorochromes are discussed.

scholarly journals Asymmetrical cross-language phonetic interaction

2020 ◽  
Author(s):  
Geoffrey Schwartz
Keyword(s):  
Phonological Representation ◽  
The Other ◽  
Alternative Theory ◽  
L2 Acquisition ◽  
The Asymmetry ◽  
Traditional Approaches ◽  
Cross Language ◽  
Different Levels

Abstract Two acoustic studies were carried out with L1 Polish learners of English. One study examined L1 phonetic drift, comparing learners of L2 English who were undergoing intensive L2 phonetic training with quasi-monolingual Polish speakers. The other study looked at L2 acquisition, comparing learners at two different levels of proficiency. Unlike most previous studies of Polish-English bilinguals, VOT data of both voiced and voiceless consonants were analyzed. In both experiments, an asymmetry was observed by which voiced stops were more susceptible to cross-language phonetic influence (CLI) than voiceless stops. These results build on evidence of a similar asymmetry observed in a number of other L1–L2 pairings. Predictions of competing phonological models are evaluated with regard to equivalence classification and phonetic CLI. It is shown that both traditional approaches to the phonological representation of voice contrasts fail to predict the observed asymmetry. An alternative theory, which predicts the asymmetry, is discussed.

scholarly journals Architecture of Component-based Information Systems over the J2EE Platform

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Daniel Perovich ◽  
Leonardo Rodrıguez Rodrıguez ◽  
Andres Vignaga
Keyword(s):  
Information Systems ◽  
Methodological Approach ◽  
Logical Structure ◽  
The Other ◽  
Model Driven ◽  
J2ee Platform ◽  
Component Based Development ◽  
Abstract Level ◽  
Definition Of ◽  
Different Levels

Component-based development can be addressed from two different fronts, or more precisely, from two different levels. One of them regards the technology used for system implementation, and the other is a previous and more abstract level, where the focus is set to the logical structure of the solution and where technological issues are not considered. Model Driven Architecture promotes such separation by distinguishing platform independent models from platform specific models. In alignment with this approach, this article proposes a mapping from the tiered and platform independent architecture for information systems resulting from the application of a widely known methodological approach, to the available constructs in the J2EE platform. This mapping allows the definition of transformations between platform independent models, resulting from the referred methodology where it is possible to abstractly reason about the solution, and platform specific models which are aligned with technological constructs and are directly implemented.

scholarly journals Quantum Physical Unclonable Functions: Possibilities and Impossibilities

Quantum ◽  
2021 ◽  
Vol 5 ◽  
pp. 475
Author(s):  
Myrto Arapinis ◽  
Mahshid Delavar ◽  
Mina Doosti ◽  
Elham Kashefi
Keyword(s):  
Large Family ◽  
Quantum States ◽  
The Other ◽  
Quantum Game ◽  
Physical Unclonable Function ◽  
Physical Unclonable Functions ◽  
Quantum Analogue ◽  
Universal Quantum ◽  
Different Levels ◽  
Comprehensive Study

A Physical Unclonable Function (PUF) is a device with unique behaviour that is hard to clone hence providing a secure fingerprint. A variety of PUF structures and PUF-based applications have been explored theoretically as well as being implemented in practical settings. Recently, the inherent unclonability of quantum states has been exploited to derive the quantum analogue of PUF as well as new proposals for the implementation of PUF. We present the first comprehensive study of quantum Physical Unclonable Functions (qPUFs) with quantum cryptographic tools. We formally define qPUFs, encapsulating all requirements of classical PUFs as well as introducing a new testability feature inherent to the quantum setting only. We use a quantum game-based framework to define different levels of security for qPUFs: quantum exponential unforgeability, quantum existential unforgeability and quantum selective unforgeability. We introduce a new quantum attack technique based on the universal quantum emulator algorithm of Marvin and Lloyd to prove no qPUF can provide quantum existential unforgeability. On the other hand, we prove that a large family of qPUFs (called unitary PUFs) can provide quantum selective unforgeability which is the desired level of security for most PUF-based applications.

Sign in / Sign up

Export Citation Format

Share Document