Comparative Skeletal Structure

During the operation of the negative electrode, some critical processes take place, which are limiting factors for the operation of lead–acid batteries. To improve the efficiency of the negative active material and minimize these processes, external application of multivector field is proposed. Two applications of the multivector field are studied: during negative paste preparation and during formation. It is established that, when applying multivector field during negative paste preparation, the chemical processes proceed more efficiently. The results are better phase composition and crystallinity of the cured paste, thus increasing the capacity of the consequently built lead batteries by 12% on average. The application of a multivector field during the formation of negative active materials in lead batteries has a positive effect on the skeletal structure, the size and shape of the Pb crystals. This ensures longer service life, which is confirmed by the 17.5% Depth of Discharge continuous tests on 12 V/75 Ah batteries. The batteries formed under the influence of external multivector field showed 20% longer cycle life. Based on the experimental result, a most probable mechanism of the influence of the multivector field on the chemical and electrochemical processes in lead batteries during negative paste preparation and formation of negative active masses is proposed.

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Flavonoids from the Genus Euphorbia: Isolation, Structure, Pharmacological Activities and Structure–Activity Relationships

Pharmaceuticals ◽

10.3390/ph14050428 ◽

2021 ◽

Vol 14 (5) ◽

pp. 428

Author(s):

Douglas Kemboi Magozwi ◽

Mmabatho Dinala ◽

Nthabiseng Mokwana ◽

Xavier Siwe-Noundou ◽

Rui W. M. Krause ◽

...

Keyword(s):

Therapeutic Potential ◽

Antioxidant Properties ◽

Structure Activity Relationship ◽

Biological Properties ◽

Therapeutic Agents ◽

Skeletal Structure ◽

Activity Relationship ◽

Hydroxyl Groups ◽

Structure Activity ◽

Review Reports

Plants of the genus Euphorbia are widely distributed across temperate, tropical and subtropical regions of South America, Asia and Africa with established Ayurvedic, Chinese and Malay ethnomedical records. The present review reports the isolation, occurrence, phytochemistry, biological properties, therapeutic potential and structure–activity relationship of Euphorbia flavonoids for the period covering 2000–2020, while identifying potential areas for future studies aimed at development of new therapeutic agents from these plants. The findings suggest that the extracts and isolated flavonoids possess anticancer, antiproliferative, antimalarial, antibacterial, anti-venom, anti-inflammatory, anti-hepatitis and antioxidant properties and have different mechanisms of action against cancer cells. Of the investigated species, over 80 different types of flavonoids have been isolated to date. Most of the isolated flavonoids were flavonols and comprised simple O-substitution patterns, C-methylation and prenylation. Others had a glycoside, glycosidic linkages and a carbohydrate attached at either C-3 or C-7, and were designated as d-glucose, l-rhamnose or glucorhamnose. The structure–activity relationship studies showed that methylation of the hydroxyl groups on C-3 or C-7 reduces the activities while glycosylation loses the activity and that the parent skeletal structure is essential in retaining the activity. These constituents can therefore offer potential alternative scaffolds towards development of new Euphorbia-based therapeutic agents.

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Echinoderm skeletal crystallography and paleobiological applications

The Paleontological Society Papers ◽

10.1017/s1089332600000255 ◽

1997 ◽

Vol 3 ◽

pp. 191-204 ◽

Cited By ~ 7

Author(s):

B. E. Bodenbender

Keyword(s):

Skeletal Structure ◽

Growth Stages ◽

Full Potential ◽

Initial Growth ◽

Developmental Sequence ◽

Coarse Scale ◽

Common Pattern ◽

Plate Morphology ◽

Oriented Parallel ◽

High Level

The crystallographic orientations of echinoderm skeletal elements can supplement standard morphological comparisons in the exploration of echinoderm evolution. At a coarse scale, many echinoderms share a crystallographic pattern in whichcaxes radiate away from the axis of pentaradial symmetry. Within this common pattern, however,caxes of different taxa can differ dramatically in their degree of variability, angles of inclination, and relationships to the external morphology of skeletal elements. Crystallographic data reflect a variety of taxon-specific influences and therefore reveal different information in different taxa. In echinoids, orientations ofcaxes in coronal plates correlate well with high-level taxonomic groupings, whilecaxes of apical plates record modes of larval development. In blastoids,caxes of radial plates have a structural interpretation, with thecaxis oriented parallel to the orientation of the surface of the radial plate during its initial growth stages. In crinoids,caxes do not correlate with taxonomic group, plate morphology, or developmental sequence, but instead correlate with relative positions of skeletal elements on the calyx. Although their full potential has yet to be explored, the varied crystallographic patterns in echinoderms have been used to clarify skeletal structure, characterize developmental anomalies, and infer homologies of skeletal plates both within specimens and between groups. A axes are less constrained in their orientations thancaxes and offer less promise of revealing novel paleobiological information.

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Development of the turtle plastron, the order-defining skeletal structure

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1600958113 ◽

2016 ◽

Vol 113 (19) ◽

pp. 5317-5322 ◽

Cited By ~ 24

Author(s):

Ritva Rice ◽

Aki Kallonen ◽

Judith Cebra-Thomas ◽

Scott F. Gilbert

Keyword(s):

Developmental Stage ◽

Cell Fate ◽

Bone Development ◽

Trachemys Scripta ◽

Skeletal Structure ◽

Evolutionary Development ◽

Extinct Species ◽

Know How ◽

Cartilage Development ◽

Dermal Bones

The dorsal and ventral aspects of the turtle shell, the carapace and the plastron, are developmentally different entities. The carapace contains axial endochondral skeletal elements and exoskeletal dermal bones. The exoskeletal plastron is found in all extant and extinct species of crown turtles found to date and is synaptomorphic of the order Testudines. However, paleontological reconstructed transition forms lack a fully developed carapace and show a progression of bony elements ancestral to the plastron. To understand the evolutionary development of the plastron, it is essential to know how it has formed. Here we studied the molecular development and patterning of plastron bones in a cryptodire turtleTrachemys scripta. We show that plastron development begins at developmental stage 15 when osteochondrogenic mesenchyme forms condensates for each plastron bone at the lateral edges of the ventral mesenchyme. These condensations commit to an osteogenic identity and suppress chondrogenesis. Their development overlaps with that of sternal cartilage development in chicks and mice. Thus, we suggest that in turtles, the sternal morphogenesis is prevented in the ventral mesenchyme by the concomitant induction of osteogenesis and the suppression of chondrogenesis. The osteogenic subroutines later direct the growth and patterning of plastron bones in an autonomous manner. The initiation of plastron bone development coincides with that of carapacial ridge formation, suggesting that the development of dorsal and ventral shells are coordinated from the start and that adopting an osteogenesis-inducing and chondrogenesis-suppressing cell fate in the ventral mesenchyme has permitted turtles to develop their order-specific ventral morphology.

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A System for Three-Dimensional Visualization of Human Jaw Motion in Speech

Journal of Speech Language and Hearing Research ◽

10.1044/jslhr.4005.1118 ◽

1997 ◽

Vol 40 (5) ◽

pp. 1118-1121 ◽

Cited By ~ 4

Author(s):

Thierry Guiard-Marigny ◽

David J. Ostry

Keyword(s):

Degrees Of Freedom ◽

Three Dimensional ◽

Visual Display ◽

Visual Speech ◽

Skeletal Structure ◽

Visualization System ◽

Motion Data ◽

Visual Speech Recognition ◽

Visualization Software ◽

Audio Track

With the development of precise three-dimensional motion measurement systems and powerful computers for three-dimensional graphical visualization, it is possible to record and fully reconstruct human jaw motion. In this paper, we describe a visualization system for displaying three-dimensional jaw movements in speech. The system is designed to take as input jaw motion data obtained from one or multi-dimensional recording systems. In the present application, kinematic records of jaw motion were recorded using an optoelectronic measurement system (Optotrak). The corresponding speech signal was recorded using an analog input channel. The three orientation angles and three positions that describe the motion of the jaw as a rigid skeletal structure were derived from the empirical measurements. These six kinematic variables, which in mechanical terms account fully for jaw motion kinematics, act as inputs that drive a real-time three-dimensional animation of a skeletal jaw and upper skull. The visualization software enables the user to view jaw motion from any orientation and to change the viewpoint during the course of an utterance. Selected portions of an utterance may be replayed and the speed of the visual display may be varied. The user may also display, along with the audio track, individual kinematic degrees of freedom or several degrees of freedom in combination. The system is presently being used as an educational tool and for research into audio-visual speech recognition. Interested researchers may obtain the software and source code free of charge from the authors.

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Microwave spectrum, boron skeletal structure, and dipole moment of 5-fluoro-2,4-dicarboheptaborane(7) (C2B5H6F)

Inorganic Chemistry ◽

10.1021/ic00308a003 ◽

1989 ◽

Vol 28 (9) ◽

pp. 1615-1619 ◽

Cited By ~ 11

Author(s):

S. S. Durso ◽

R. A. Sheeks ◽

E. V. O'Gorman ◽

Robert A. Beaudet

Keyword(s):

Dipole Moment ◽

Microwave Spectrum ◽

Skeletal Structure

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The ACT Hand: design of the skeletal structure

IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004 ◽

10.1109/robot.2004.1308775 ◽

2004 ◽

Cited By ~ 55

Author(s):

M. Vande Weghe ◽

M. Rogers ◽

M. Weissert ◽

Y. Matsuoka

Keyword(s):

Skeletal Structure

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Regressive Vowel Harmony in Libyan Arabic

(Faculty of Arts Journal) مجلة كلية الآداب - جامعة مصراتة ◽

10.36602/faj.2019.n14.09 ◽

2019 ◽

pp. 36-50

Author(s):

Yousef Mokhtar Elramli ◽

Tareq Bashir Maiteq

Keyword(s):

Vowel Harmony ◽

Skeletal Structure ◽

Front Vowel ◽

Person Plural ◽

The Third ◽

Third Person ◽

The Third Person ◽

The City

The aim of this paper is to study Regressive vowel harmony induced by a suffixal back round vowel in the Libyan Arabic dialect spoken in the city of Misrata. The skeletal structure in the collected words is a /CVCVC-/ stem followed by the third person plural suffix /-u/. Consequently, the derived form of the examined words becomes /CVCVCV/. Following a rule of re-syllabification, the coda of the ultimate syllable in the stem becomes the onset of the newly formed syllable (ultimate in the derived form). Thus, in the presence of the suffix /-u/ in the derived form, all vowels in the word must harmonise with the [+round] feature of /-u/ unless there is a high front vowel /i/ intervening. In such cases, the high front vowel is defined as an opaque segment that is incompatible with the feature [+round]. Syllable and morpheme boundaries within words do not seem to contribute to blocking the regressive spreading of harmony. An autosegmental approach to analyze these words is adopted here. It is concluded that there are two sources in underlying representations for regressive vowel harmony in Libyan Arabic. One source is floating [+round] and another source is [+round].

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