scholarly journals Assessments of bilateral asymmetry with application in human skull analysis

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258146
Author(s):  
M. Hou ◽  
M. J. Fagan
Keyword(s):  
Bilateral Symmetry ◽  
Directional Asymmetry ◽  
Large Collection ◽  
Human Skull ◽  
Collective Levels ◽  
Wide Range ◽  
Observational Errors ◽  
Point Line ◽  
Exact Relationship ◽  
Biological And Medical Applications

As a common feature, bilateral symmetry of biological forms is ubiquitous, but in fact rarely exact. In a setting of analytic geometry, bilateral symmetry is defined with respect to a point, line or plane, and the well-known notions of fluctuating asymmetry, directional asymmetry and antisymmetry are recast. A meticulous scheme for asymmetry assessments is proposed and explicit solutions to them are derived. An investigation into observational errors of points representing the geometric structure of an object offers a baseline reference for asymmetry assessment of the object. The proposed assessments are applicable to individual, part or all point pairs at both individual and collective levels. The exact relationship between the developed treatments and the widely used Procrustes method in asymmetry assessment is examined. An application of the proposed assessments to a large collection of human skull data in the form of 3D landmark coordinates finds: (a) asymmetry of most skulls is not fluctuating, but directional if measured about a plane fitted to shared landmarks or side landmarks for balancing; (b) asymmetry becomes completely fluctuating if one side of a skull could be slightly rotated and translated with respect to the other side; (c) female skulls are more asymmetric than male skulls. The methodology developed in this study is rigorous and transparent, and lays an analytical base for investigation of structural symmetries and asymmetries in a wide range of biological and medical applications.

scholarly journals Applications of Photocatalytic Disinfection

2010 ◽  
Vol 2010 ◽  
pp. 1-11 ◽  
Author(s):  
Joanne Gamage ◽  
Zisheng Zhang
Keyword(s):  
Indoor Air ◽  
Food Industry ◽  
Plant Protection ◽  
Water Disinfection ◽  
Photocatalytic Disinfection ◽  
Wide Range ◽  
Test Organisms ◽  
Drinking Water Disinfection ◽  
End Use ◽  
Biological And Medical Applications

Due to the superior ability of photocatalysis to inactivate a wide range of harmful microorganisms, it is being examined as a viable alternative to traditional disinfection methods such as chlorination, which can produce harmful byproducts. Photocatalysis is a versatile and effective process that can be adapted for use in many applications for disinfection in both air and water matrices. Additionally, photocatalytic surfaces are being developed and tested for use in the context of “self-disinfecting” materials. Studies on the photocatalytic technique for disinfection demonstrate this process to have potential for widespread applications in indoor air and environmental health, biological, and medical applications, laboratory and hospital applications, pharmaceutical and food industry, plant protection applications, wastewater and effluents treatment, and drinking water disinfection. Studies on photocatalytic disinfection using a variety of techniques and test organisms are reviewed, with an emphasis on the end-use application of developed technologies and methods.

scholarly journals Cytospora (Diaporthales) in China

2020 ◽  
Vol 45 (1) ◽  
pp. 1-45 ◽  
Author(s):  
X.L. Fan ◽  
J.D.P. Bezerra ◽  
C.M. Tian ◽  
P.W. Crous
Keyword(s):  
New Species ◽  
Host Plants ◽  
Southwest China ◽  
New Combination ◽  
Large Collection ◽  
Dna Phylogeny ◽  
The Past ◽  
Worldwide Distribution ◽  
Wide Range ◽  
Woody Host

Members of the genus Cytospora are often reported as endophytes, saprobes or phytopathogens, primarily causing canker diseases of woody host plants. They occur on a wide range of hosts and have a worldwide distribution. Although several species have in the past been reported from China, the vast majority are not known from culture or DNA phylogeny. The primary aim of the present study was thus to clarify the taxonomy and phylogeny of a large collection of Cytospora species associated with diverse hosts in China. Cytospora spp. were collected in northeast, northwest, north and southwest China, indicating that the cold and dry environments favour these fungi. In this paper, we provide an assessment of 52 Cytospora spp. in China, focussing on 40 species represented by 88 isolates from 28 host genera. Based on a combination of morphology and a six-locus phylogeny (ITS, LSU, act1, rpb2, tef1-α and tub2), 13 new species and one new combination are introduced. The majority of the species investigated here appear to be host-specific, although further collections and pathogenicity studies will be required to confirm this conclusion.

Planarian Hox genes: novel patterns of expression during regeneration

Development ◽  
1997 ◽  
Vol 124 (1) ◽  
pp. 141-148
Author(s):  
J.R. Bayascas ◽  
E. Castillo ◽  
A.M. Munoz-Marmol ◽  
E. Salo
Keyword(s):  
Hox Genes ◽  
Bilateral Symmetry ◽  
Sister Group ◽  
Model Systems ◽  
Hox Cluster ◽  
Positional Identity ◽  
Wide Range ◽  
Differential Timing ◽  
Anteroposterior Polarity

Platyhelminthes are widely considered to be the sister group of coelomates (Philippe, H., Chenuil, A. and Adoutte, A. (1994)Development 1994 Supplement, 15–24) and the first organisms to show bilateral symmetry and cephalization. Within this phylum, the freshwater planarians (Turbellaria, Tricladida) have been used as model systems for studying bidirectional regeneration (Slack, J. M. W. (1980) J. Theor. Biol 82, 105–140). We have been attempting to identify potential pattern-control genes involved in the regeneration of planarian heads and tails after amputation. Since Hox cluster genes determine positional identity along the anteroposterior axis in a wide range of animals (Slack, J. M. W., Holland, P. W. H. and Graham, C. F. (1993) Nature 361,490-492), we performed an extensive search for Hox-related genes in the planarian Dugesia(G)tigrina. Sequence analyses of seven planarian Dthox genes (Dthox-A to Dthox-G) reveal high similarities with the homeodomain region of the Hox cluster genes, allowing us to assign planarian Dthox genes to anterior and medial Hox cluster paralogous groups. Whole-mount in situ hybridization studies in regenerating adults showed very early, synchronous and colocalized activation of Dthox-D, Dthox-A, Dthox-C, Dthox-E, Dthox-G and Dthox-F. After one hour of regeneration a clear expression was observed in all Dthox genes studied. In addition, all seemed to be expressed in the same regenerative tissue, although in the last stages of regeneration (9 to 15 days) a differential timing of deactivation was observed. The same Dthox genes were also expressed synchronously and were colocalized during intercalary regeneration, although their expression was delayed. Terminal regeneration showed identical Dthox gene expression in anterior and posterior blastemas, which may prevent these genes from directing the distinction between head and tail. Finally, continuous expression along the whole lateral blastema in sagittal regenerates reflected a ubiquitous Dthox response in all types of regeneration that was not related specifically with the anteroposterior polarity.

scholarly journals A 3D Printed Jet Mixer for Centrifugal Microfluidic Platforms

Micromachines ◽  
2020 ◽  
Vol 11 (7) ◽  
pp. 695 ◽  
Author(s):  
Yunxia Wang ◽  
Yong Zhang ◽  
Zheng Qiao ◽  
Wanjun Wang
Keyword(s):  
3D Printing ◽  
Three Dimensional ◽  
Mixing Efficiency ◽  
Medical Applications ◽  
Microfluidic Platforms ◽  
Mixing Performance ◽  
Wide Range ◽  
3D Printed ◽  
Miscible Liquids ◽  
Biological And Medical Applications

Homogeneous mixing of microscopic volume fluids at low Reynolds number is of great significance for a wide range of chemical, biological, and medical applications. An efficient jet mixer with arrays of micronozzles was designed and fabricated using additive manufacturing (three-dimensional (3D) printing) technology for applications in centrifugal microfluidic platforms. The contact surface of miscible liquids was enhanced significantly by impinging plumes from two opposite arrays of micronozzles to improve mixing performance. The mixing efficiency was evaluated and compared with the commonly used Y-shaped micromixer. Effective mixing in the jet mixer was achieved within a very short timescale (3s). This 3D printed jet mixer has great potential to be implemented in applications by being incorporated into multifarious 3D printing devices in microfluidic platforms.

The relationship between asymmetry, size and unusual venation in honey bees (Apis mellifera)

2016 ◽  
Vol 106 (3) ◽  
pp. 304-313 ◽  
Author(s):  
S. Łopuch ◽  
A. Tofilski
Keyword(s):  
Apis Mellifera ◽  
Honey Bees ◽  
Directional Asymmetry ◽  
Right Wing ◽  
Wing Size ◽  
Large Variability ◽  
Normal Individuals ◽  
Wide Range ◽  
The Right ◽  
The Relationship

AbstractDespite the fact that symmetry is common in nature, it is rarely perfect. Because there is a wide range of phenotypes which differs from the average one, the asymmetry should increase along with deviation. Therefore, the aim of this study was to assess the level of asymmetry in normal individuals as well as in phenodeviants categorized as minor or major based on abnormalities in forewing venation in honey bees. Shape fluctuating asymmetry (FA) was lower in normal individuals and minor phenodeviants compared with major phenodeviants, whereas the former two categories were comparable in drones. In workers and queens, there were not significant differences in FA shape between categories. FA size was significantly lower in normal individuals compared with major phenodeviant drones and higher compared with minor phenodeviant workers. In queens, there were no significant differences between categories. The correlation between FA shape and FA size was significantly positive in drones, and insignificant in workers and queens. Moreover, a considerable level of directional asymmetry was found as the right wing was constantly bigger than the left one. Surprisingly, normal individuals were significantly smaller than minor phenodeviants in queens and drones, and they were comparable with major phenodeviants in all castes. The correlation between wing size and wing asymmetry was negative, indicating that smaller individuals were more asymmetrical. The high proportion of phenodeviants in drones compared with workers and queens confirmed their large variability. Thus, the results of the present study showed that minor phenodeviants were not always intermediate as might have been expected.

Meteor luminosity and ionization

1963 ◽  
Vol 271 (1344) ◽  
pp. 120-128 ◽  
Keyword(s):  
Mean Velocity ◽  
Wide Range ◽  
Observational Errors ◽  
The Relationship

Simultaneous photographic and radio echo observations which have been made to study the relationship between meteor luminosity and ionization are described. The results show a scatter larger than would be expected from the estimated observational errors and it is concluded that this is due to inherent differences in the meteors observed. It is shown that the ratio of luminosity to ionization is a function of meteor brightness as well as velocity and, in order to determine the interdependence of these parameters, a large amount of data covering a wide range of meteor brightnesses and velocities will be necessary. Values for the ionizing efficiency and probability of ionization for a mean photographic magnitude of +1.1 and a mean velocity of 32 km/s are given.

scholarly journals A MINERALOGICAL STUDY OF SOME MYCENAEAN SEALS EMPLOYING MOBILE RAMAN MICROSCOPY

2017 ◽  
Vol 43 (2) ◽  
pp. 804 ◽  
Author(s):  
G. Economou ◽  
E. Konstantinidi-Syvridi ◽  
I. Kougemitrou ◽  
M. Perraki ◽  
D.C. Smith
Keyword(s):  
Raman Spectra ◽  
Spectroscopic Analysis ◽  
Large Collection ◽  
Ancient Greek ◽  
Museum Exhibit ◽  
Raman Spectroscopic ◽  
Wide Range ◽  
The World ◽  
Mineralogical Study ◽  
Raman Spectroscopic Analysis

The National Archaeological Museum in Athens is the largest archaeological museum in Greece, and one of the most important museums in the world, devoted to Ancient Greek art and history. Among other exhibits, it owns a large collection of gemstones some of which were used during prehistoric times (Mycenaean period) as seals. Their shape varies from round to oval, flattish or cylindrical, and they are delicately engraved as intaglios with a variety of depictions (lions, bulls, man, etc). They show a wide range of colours from reddish, brown, to purplish and blue. The six sealstones described here come from the Chamber Tombs of Mycenae (15th-14th cent. BC). Museum exhibit labels recognize them as varieties of quartz such as jasper (NAM 3138), sardonyx (NAM 2316 & 2865), agate (NAM 4928), amazonite (NAM 2863) and gold-mounted carnelian (NAM 6489). Raman Spectroscopic analysis has been carried out with a new MRM (Mobile Raman Microscope) using a Kaiser Holoprobe with a NIR 785nm laser. The Raman spectra acquired from 1s-60s measurements confirmed that, in all six sealstones, quartz was the major mineral species clearly identified by its characteristic peaks. The second most important phase was moganite, a little-known polymorph of quartz. The amber-coloured sealstone (NAM 6489) was confirmed as carnelian, whereas the blue-green amazonite-coloured sealstone (NAM 2863) was not detected as amazonite. Small amounts of haematite were detected in the NAM 2865 & NAM 3138.

scholarly journals An extended toolkit for production and use of RVdG-CVS-N2c rabies viral vectors uncovers hidden hippocampal connections

2021 ◽  
Author(s):  
Anton Sumser ◽  
Maximilian Joesch ◽  
Peter Jonas ◽  
Yoav Ben-Simon
Keyword(s):  
Viral Vectors ◽  
Molecular Tools ◽  
Cell Type ◽  
Large Collection ◽  
Neuronal Connectivity ◽  
Retrograde Labeling ◽  
Neuronal Populations ◽  
Wide Range ◽  
Cell Type Specific ◽  
Cortical Microcircuit

From the large collection of molecular tools used to investigate neuronal connectivity, envA-pseudotyped rabies viral vectors (RVdGenvA) uniquely enable cell-type specific, trans-synaptic retrograde labeling. However, widespread use of the powerful and flexible method is to date hindered by low-yield and cumbersome production pipelines. Here, we report the development of new cell lines, which significantly reduce production time while increasing viral titer and eliminating background contamination from native-coat particles. We further show that RVdGenvA-CVS-N2c vectors produced using this system retain their enhanced retrograde-trafficking when compared with SAD-B19 vectors, allowing us to uncover undescribed cortico-hippocampal connections and to monitor activity in a cortical microcircuit of behaving animals. Along with new suites of AAV and RVdG-CVS-N2c vectors, developed to enable retrograde labeling from a wide range of neuronal populations and tailored for diverse experimental requirements, we present here an optimal system for mapping, manipulating and imaging of neuronal circuits.

scholarly journals Asymmetry measures and allometric growth parameter estimates for investigate effect of early feed restriction on deviation from bilateral symmetry in broiler chickens

2008 ◽  
Vol 51 (6) ◽  
pp. 611-619 ◽  
Author(s):  
M. Mendes
Keyword(s):  
Broiler Chickens ◽  
Bilateral Symmetry ◽  
Developmental Stability ◽  
Directional Asymmetry ◽  
Feed Restriction ◽  
Model Parameters ◽  
Allometric Growth ◽  
Feeding Programs ◽  
Ad Libitum ◽  
Asymmetry Measures

Abstract. The purpose of this study is to investigate the effect of different feeding programs such as ad libitum feeding (AD), 20 % feed restriction based on ad libitum group (FR1) and not fed between 9 a.m. and 3 p.m. (FR2) on deviation from bilateral symmetry or developmental stability in broiler chickens by means of two different approaches namely asymmetry measures and allometric growth model parameters. The weekly left and right sides of shank length, shank width, wing length and face width of chickens were collected from 7 days of age to 42 days of age. Results of this study showed that the deviations from the bilateral symmetry were mostly in fluctuating asymmetry (FA) in the FR1 group birds. On the other hand, the deviations from the bilateral symmetry in the birds in group AD and FR2 were mostly in the form of anti-symmetry (AS) and directional asymmetry (DA) respectively. In this study, the deviation from the bilateral symmetry was mostly in FA type for the measured morphological characters for the FR1 group, and the FA level was usually lower indicating higher welfare level and lower developmental instability for these animals than that of the AD and FR2 groups. Allometric growth coefficients for evaluating the effects of the feeding programs on the developmental stability were a little bit different from the findings obtained by the asymmetry measures‘ being taken into account. Allometric growth parameters, therefore, should be taken into consideration, along with asymmetry measures when investigating effect of rearing conditions or environmental conditions on developmental stability. As a conclusion, intensive feeding (AD) and long-term feed restriction (FR2) can be said as an important environmental factor affecting developmental stability and dependently the animal welfare and performance.

Styli and book clasps from excavations at the Great Shepetovka Settlement

2021 ◽  
Vol 31 ◽  
pp. 264-276
Author(s):  
A. Peskova ◽  
◽  
A. Kononovich ◽  
Keyword(s):  
Large Collection ◽  
13Th Century ◽  
Considerable Part ◽  
Wide Range ◽  
Writing Tools ◽  
The Village

During excavations of the Od-Russian fortified settlement near the village of Gorodishche of the Shepe- tovka District of Khmelnitsk Oblast (Ukraine), a large collection of writing tools (styli) (20/24 items) was obtained, as well as parts of book clasps (4 items). Analysis of the find has shown that the majority of the styli found at the site belong to the commonly distributed general Russian types 3, 6, 7, and 11 (after the typology by A. F. Medvedev and B. B. Ovchinnikova) used during a wide range of the 11th–13th century. One stylus belongs to type 13 identified by special- ists as a south-western type; two styli are a simplified variant of type 8. The plan of the findspots suggests a connection of the considerable part of the finds with the summit of the Gorodishche hill, i. e. the zone of concentration of fragments of bells and hoards of silver ornaments, including the hoard containing pending lead seals

Sign in / Sign up

Export Citation Format

Share Document