A Hermaphroditic Specimen of Weathervane Scallop, Patinopecten caurinus, in Alaska

1971 ◽  
Vol 28 (4) ◽  
pp. 608-609 ◽  
Author(s):  
Daniel Hennick
Keyword(s):  
Microscopic Examination ◽  
Annual Ring ◽  
Annual Rings ◽  
Placopecten Magellanicus ◽  
Male And Female ◽  
The Third ◽  
Rare Phenomenon ◽  
Sea Scallops

Hermaphroditism in sea scallops is a relatively rare phenomenon. Observations on two hermaphroditic specimens of Placopecten magellanicus have been documented in the literature. Recent studies on the weathervane scallop, Patinopecten caurinus, in Alaska, have resulted in the discovery of a single hermaphroditic individual from sexual examination through dissection of more than 25,000 individuals over a 3-year study period. The specimen appeared to be a functional hermaphrodite, as both male and female follicules containing well-developed eggs and sperms were clearly evident from microscopic examination. Shell examination showed the animal had formed seven annual rings indicating the animal had spawned more than one season, since weathervane scallops mature after formation of the third annual ring.

scholarly journals Improved Hough Transform and Total Variation Algorithms for Features Extraction of Wood

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 466
Author(s):  
Weiwei Du ◽  
Yarui Xi ◽  
Kiichi Harada ◽  
Yumei Zhang ◽  
Keiko Nagashima ◽  
...  
Keyword(s):  
Total Variation ◽  
Hough Transform ◽  
Annual Ring ◽  
Wood Quality ◽  
Volume Density ◽  
Low Noise ◽  
Impact Factors ◽  
Annual Rings ◽  
New Model ◽  
Model Combining

Research shows that the intensity impact factors of wood, such as late timber ratio, volume density and the intensity of itself, correlate with the width of wood annual rings. Therefore, extracting wood annual ring information from wood images is helpful for evaluating wood quality. During the past few years, many researchers have conducted defect detection by studying the information of wood images. However, there are few in-depth studies on the statistics and calculation of wood annual ring information. This study proposes a new model combining the Total Variation (TV) algorithm and the improved Hough transform to accurately measure the wood annual ring information. The TV algorithm is used to suppress image noise, and the Hough transform is for detecting the center of the wood image. Moreover, the edges of wood annual rings are extracted, and the statistical ring information is calculated. The experimental results show that the new model has good denoising capability, clearly extract the edges of wood annual rings and calculate the related parameters from the indoor wood images of the processed logs and the unprocessed low-noise logs.

Quantitative Bestimmung der hydrierten Pterine und des Xanthommatins in den Augen von Ceratitis capitata WIED (Dipt. Trypetidae)

1965 ◽  
Vol 20 (4) ◽  
pp. 318-322 ◽  
Author(s):  
Irmgard Ziegler ◽  
M. Feron
Keyword(s):  
Quantitative Determination ◽  
Ceratitis Capitata ◽  
Male And Female ◽  
The Third ◽  
Quantitative Bestimmung ◽  
Drastic Increase

In the eyes of male and female flies a quantitative determination of the tetrahydropterin, the corresponding dihydro-compound (Sepiapterin) and of xanthommatin from 0—5 days after hatching was made. The increase of xanthommatin almost stops 24 hours after hatching; about 13 μg are present after that time. The tetrahydropterin, after a drastic increase during the first 24 hours, remains at a level of about 1,1 — 1,2 µg. In contrast the dihydrocompound which is nearly absent at the time of hatching is deposited on the eye-granules between the third and fifth day. At that time, especially in the male the dihydropterin/tetrahydropterin ratio is increased. Starvation during the first 24 hours has essentially no effect on the amount of xanthommation whereas the amount of pterins is markedly reduced.

Seasonal Variation in Traumatic Resin Canal Formation in Chamaecyparis Obtusa Phloem

IAWA Journal ◽  
1998 ◽  
Vol 19 (2) ◽  
pp. 181-189 ◽  
Author(s):  
Keiko Kuroda
Keyword(s):  
Annual Ring ◽  
Stem Canker ◽  
Chamaecyparis Obtusa ◽  
Resin Canal ◽  
Annual Rings ◽  
Secondary Phloem ◽  
Resinous Stem Canker ◽  
Traumatic Resin Canals ◽  
Resin Canals ◽  
Artificial Wounding

Trunks of Chamaecyparis obtusa were injured to examine seasonal differences in traumatic resin canal formation in secondary phloem. Even after wounding during winter, differentiation of axial parenchyma into epithelium was initiated, and vertical resin canals formed. After winter wounding, resin canal development was slower and the tangential extent of resin canals was narrower than after spring wounding, and it took one to two months until resin secretion began. After spring wounding, the sites of resin canal formation were the 1- and 2-year-old annual rings of phloem. In August, the location of resin canal formation shifted into the current and 1-year-old annual ring. Resin canals never formed in secondary phloem areas that were 3 or more years old. In C. obtusa trunks that are affected by the resinous stem canker, numerous tangentiallines of resin canals are found throughout the phloem, not just recent and 1- to 2-year-old phloem. The present research indicates that these many lines of resin canals were not formed at one time, and that the stimuli that induce traumatic resin canals must occur repeatedly over many years. The data on artificial wounding effects are useful for understanding resinous stem canker.

INTERVASCULAR PITTING ACROSS THE ANNUAL RING BOUNDARY IN BETULA PLATYPHYLLA VAR. JAPONICA AND FRAXINUS MANDSHURICA VAR. JAPONICA

IAWA Journal ◽  
2004 ◽  
Vol 25 (2) ◽  
pp. 129-140 ◽  
Author(s):  
Yuzou Sano
Keyword(s):  
Annual Ring ◽  
Peripheral Region ◽  
Betula Platyphylla ◽  
Annual Rings ◽  
Fraxinus Mandshurica ◽  
Common Wall ◽  
Pit Membrane ◽  
Perforation Plates ◽  
Soluble Material ◽  
Ring Boundary

The structure of intervascular pits, located at the boundary between the outermost and the second youngest annual rings in Betula platyphylla var. japonica and Fraxinus mandshurica var. japonica was examined by field-emission scanning electron microscopy. Unilaterally compound pits were present in the intervascular common wall at the annual ring boundary in both species. On the outer annual ring side of the unilaterally compound pits, outlines of pit membranes were curved or trifoliate, and each pit aperture was often elongated and curved. The porosity of the intervascular pit membranes differed between the two species. In B. platyphylla var. japonica, microfibrils were loosely packed in the peripheral region of each pit membrane, and openings of up to 300 nm in width were observed. By contrast, microfibrils were densely packed throughout the entire pit membranes in F. mandshurica var. japonica, and no openings perforating the pit membranes entirely were found. In addition, each species exhibited some unique features. In B. platyphylla var. japonica, extensive ethanol-soluble material was detected not only in the intervascular pits but also on scalariform perforation plates. In F. mandshurica var. japonica, we observed fine curly fibrils of unkown chemical composition in the intervascular pit membranes.

Dental Interns’ Perceptions of Their Training Experiences at Different Training Centers: A Look at Work Environment and Supervision

2021 ◽  
Author(s):  
Ali Alenezi
Keyword(s):  
Work Environment ◽  
Learning Outcomes ◽  
Field Experience ◽  
Learning Experience ◽  
Training Experience ◽  
Male And Female ◽  
The Third ◽  
Level Of Satisfaction ◽  
Strongly Agree ◽  
High Level

Abstract Background: the aim of this study was to explore dental interns perceptions on their learning environment and supervision. Methods: This survey was in form of questioner in which interns are required to fill and submit at the end of each training rotation. The questionnaire includes 20 items and was divided into three main parts: the first part of the questionnaire evaluated the interns perception toward the learning outcomes obtained from the field experience and their development. The second part of the study assessed the interns' perceptions toward their supervisors. The third part of the questionnaire investigated the interns' perceptions toward training centers facilities. Results: A total number of 234 questioners were filled and submitted by interns in which 134 from male intern (57.3%) and 100 from female interns (42.7%). In general, the interns from both genders appeared very satisfied with their training experience. With all the questionnaire 20 items, more than 75% of the obtained answers was either agree or strongly agree with similar obtained from both male and female interns. Conclusions: High level of satisfaction can be obtained when the the field experience outcomes is clearly explained to the dental interns. In addition, the availability of supervisors with full awareness of learning outcomes will improve the learning experience of dental interns.

scholarly journals Cambridge University Natural Radiocarbon Measurements IV: Nuclear-Weapon Testing and the Atmospheric Radiocarbon Concentration

Radiocarbon ◽  
1961 ◽  
Vol 3 ◽  
pp. 77-80 ◽  
Author(s):  
H. Godwin ◽  
E. H. Willis
Keyword(s):  
Rapid Growth ◽  
Nuclear Weapon ◽  
Annual Ring ◽  
Populus Nigra ◽  
Annual Rings ◽  
Cambridge University ◽  
Annual Crops ◽  
Nuclear Weapon Testing ◽  
Weapon Testing

In continuance of investigations upon successive annual crops of oats reported in Radiocarbon Supplement, Volume 2, we undertook the analysis of successive annual rings of a tree that had been growing throughout the period covered by the oat-crop assays, namely 1953 to 1959. The selected tree was a straight-boled specimen of Populus nigra from the Forestry Commission's plantations at Santon Downham, near Thetford, Norfolk. It had been planted in 1929 and was felled on 21 October, 1959. Shortly afterwards, it was brought into the laboratory and sawn into slices just over 1 in. thick. The surfaces having been smoothed, the annual-ring contacts were marked, and within each annual ring the inner (spring) wood was marked off from the outer (autumn) wood. The tree had been chosen as one exhibiting rapid growth and it proved fairly easy to dissect off with a chisel all the separate half-rings between spring 1953 and the end of 1959. In the event, activities were determined only upon four of the half or whole rings.

scholarly journals Profile of Colorectal Tumor in Gastroentero-Hepatology Center, Department of Internal Medicine, Dr Soetomo Hospital, Surabaya

2020 ◽  
Vol 56 (1) ◽  
pp. 15
Author(s):  
Husin Thamrin ◽  
Khafidhotul Ilmiah ◽  
Ni Wajan Tirthaningsih
Keyword(s):  
Colorectal Cancer ◽  
Medical Records ◽  
Colorectal Tumor ◽  
Age And Gender ◽  
Male And Female ◽  
The Third ◽  
Common Cancer ◽  
Significant Difference ◽  
And Gender ◽  
Ethical Clearance

Colorectal cancer has became burden in the world.The latest study shows that colorectal cancer is the third most common cancer in men and second most common cancer in women globally. There are difference characteristic of epidemiology in every countries. Moreover, there is no study that represents epidemiology of colorectal cancer in Indonesia yet, especially in East Java. The aim of this study was to describe colorectal tumor profile by age and gender in Gastroentero-Hepatology Center, Dr Soetomo Hospital. This study has received a certificate of Ethical Clearance No.273/Panke.KKE/IV/2015, a descriptive retrospective study. We collected data using medical records, and patients who have been colonoscopy examination and suspected colorectal tumor were included. There were 201 patients, divided to 100 males and 101 females. The peak of incidence was on 51-60 years old group, but on the 31-40 years old incidence of colorectal tumor was increased. The youngest patient was 17 years old. And tumors are more likely develop in distal area, especially in rectum. This study shows a different characteristic profile of colorectal tumor, where tumor is developed at young people and there is no significant difference between male and female for the incidence.

scholarly journals The Perceptions of Teachers at the Secondary Schools in Bani Obaid District at Irbid City for their Schools by Considering the Schools as Learning Organizations: تصورات معلمي المرحلة الثانوية في لواء بني عبيد بمدينة إربد لمدارسهم كمنظمات متعلمة

2020 ◽  
Vol 4 (25) ◽  
Author(s):  
Asem Abdullah Al-Essa
Keyword(s):  
Critical Thinking ◽  
Secondary Schools ◽  
Mental Models ◽  
Learning Organizations ◽  
Years Of Experience ◽  
Male And Female ◽  
The Third ◽  
Female Teachers ◽  
General Performance ◽  
Perceptions Of Teachers

This study investigates the perceptions of teachers at the secondary schools in Bani Obaid district at Irbid city for their schools by considering the schools as learning organizations. This study discovers the differences in participant responses that are related to their perceptions by considering the schools as educated organizations based on the following factors: gender, qualifications, and years of experience. To achieve the objectives of the study, the researcher follows the descriptive methodology by preparing a questionnaire which includes (35) parts. The sample of the study consists of (250) male and female teachers in the secondary schools at Bani Obaid district. They were collected randomly from the total number of teachers in that district which is (413). They represent (60%) of the teachers in the district. The perceptions of the teachers of the secondary schools at Bani Obaid district at Irbid city for their schools as educated organizations got (5,64) for the highest average based on the general performance using the tool. The results based on the scopes of the study are as the following: working as a team got the highest average (3.91). The followed scope is the mental models (3.66). The third one is related to the personal ability with average (3.91) then the collective vision with average (3.50) and lastly, the critical thinking with average (3.49). There were not much significant statistical differences in level (α≤0.05) in the sample responses which are related to the study scopes and tool based on the sex and years of experience in addition to (collective vision and personal ability) dimensions based on the qualification. There were significant statistical differences in level (α≤0.05) in the sample responses which are related to the scopes of (collective vision, mental models and teamwork) based on the qualification dimension specially the bachelor degree. Based on the results of the research, the researcher recommends providing financial and moral incentives for the distinguished secondary schools to apply the principles of the educated schools.

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