scholarly journals THE INFLUENCE OF CHROMOSOME CONTENT ON THE SIZE AND SHAPE OF SPERM HEADS IN DROSOPHILA MELANOGASTER AND THE DEMONSTRATION OF CHROMOSOME LOSS DURING SPERMIOGENESIS

Genetics ◽  
1975 ◽  
Vol 79 (2) ◽  
pp. 231-264
Author(s):  
Robert Walter Hardy
Keyword(s):  
Seminal Receptacle ◽  
Three Dimensional ◽  
Sperm Head ◽  
Chromosome Loss ◽  
Head Shape ◽  
Frequency Distributions ◽  
Volume Measurements ◽  
Chromatin Material ◽  
The Mean ◽  
Sperm Nuclei

ABSTRACT The volumes of sperm heads were estimated from three-dimensional reconstructions of serially sectioned bundles of nearly mature spermatid nuclei. Cysts from males in which all sperm are expected to have comparable amounts of chromatin (X/Y and In(3LR)/+) show unimodal frequency distributions of nuclear volumes, whereas cysts from males in which meiotic segregation is expected to deliver unequal amounts of chromatin material to spermatid nuclei show two (XY/O and XY/Y) or more (T(2;3)/+ and C(2L);C(2R)) modes. The mean volumes of the subpopulations in these cases are related in the same proportions as the metaphase lengths of their chromosomal complements. Thus the volumes of sperm nuclei are proportional to their DNA content. Sperm head shape, on the other hand, does not appear to be very sensitive to chromosomal constitution, as heads of different size do not vary greatly in shape.—The numbers of sperm heads in the various size classes in a cyst depart from mendelian expectations; these departures are caused by the elimination, during individualization, of chromosomes contained within micronuclei that are formed in spermatids at the end of the second meiotic division. The effect of this chromosome loss is to increase the proportion of nullosomic gametes in the sperm pool.—The relative frequencies of XY-bearing and nullo-X, nullo-Y sperm in XY/O males were estimated from the volume measurements. Taking this estimate as a measure of the fertilizing population, it is possible to infer from the change in sex ratio over time following insemination, that XY-bearing sperm have an advantage of 1.5 over nullo-X, nullo-Y sperm in leaving the seminal receptacle of the female for fertilization of ova.

Patterns of variability in DNA content and nuclear volume in regenerating cultures of Nicotiana tabacum

1983 ◽  
Vol 25 (4) ◽  
pp. 354-360 ◽  
Author(s):  
Mary B. Berlyn
Keyword(s):  
Callus Culture ◽  
Dna Content ◽  
Isonicotinic Acid ◽  
Acid Hydrazide ◽  
Callus Cultures ◽  
Nuclear Volume ◽  
Frequency Distributions ◽  
Volume Measurements ◽  
The Mean ◽  
Undifferentiated Callus

The frequency distributions of DNA content per nucleus were examined in five isonicotinic acid hydrazide (INH) resistant callus lines of tobacco and in developing buds and shoots regenerating from the lines. They were compared with the distribution for a diploid plant, with an estimated 2C value of 7.8 pg. The total range of all the callus cultures was between 5 and 40 pg, with modes between 7 and 16 pg. In the oldest (6 years) callus culture, the mean and standard deviation were lower in the buds developing from the culture than in the undifferentiated callus: however, older shoots again showed a higher mean and more disperse distribution. In contrast, for 4-year-old secondary callus cultures from plants simultaneously regenerated from a second INH-resistant (I 24) line, the mean DNA content per nucleus of the developing buds was higher than that of the undifferentiated callus. Less variation and a more nearly diploid distribution were observed in a 2-year-old callus culture of a fertile plant chosen from the progeny of one of these I 24 plants and in the buds and older shoots regenerated from this culture. Thus, in these five moderately heteroploid cultures a consistent pattern of selection for euploid levels of DNA did not occur during the observed stages of regeneration. Examination of volume as well as DNA content of nuclei in the different tissues showed that variability of nuclear volume measurements, as indicated by coefficients of variation, was correlated with variability of DNA content per nucleus, although measurements of volume and DNA content per individual nucleus were not always highly correlated. It is suggested that high coefficient of variation of nuclear volume, in conjunction with large nuclear size, could serve as a rapid preliminary indicator of highly heterogeneous DNA levels in the nuclear population of Nicotiana cultures.

scholarly journals The correlation between osteopontin level and radiation response of malignant gliomas at Cipto Mangunkusumo Hospital

2016 ◽  
Vol 2 (6) ◽  
pp. 330
Author(s):  
Isnaniah Hasan ◽  
Sri Mutya Sekarutami ◽  
Renindra A. Aman ◽  
Nurjati C. Siregar ◽  
Rahmad Mulyadi
Keyword(s):  
Malignant Glioma ◽  
Ct Scan ◽  
Tumor Volume ◽  
Malignant Gliomas ◽  
Tumor Hypoxia ◽  
Three Dimensional ◽  
Radiation Response ◽  
Volume Measurements ◽  
The Mean ◽  
Magnetic Resonance Imaging Mri

<p>Osteopontin is an endogenous molecular marker for tumor hypoxia, and hypoxia is one of the factors that determine the aggressiveness of the disease. The purpose of this study is to determine the correlation between osteopontin levels and radiation response in malignant glioma. A retrospective cohort study was conducted on 15 malignant glioma patients who underwent radiation therapy from July 2004 to May 2015 at the RSUPN Dr. Cipto Mangunkusumo Hospital. Osteopontin levels were measured from paraffin-embedded tissue using a commercial ELISA kit. Tumor volume was calculated using computed tomography (CT) scan and magnetic resonance imaging (MRI) images, based on three-dimensional volume measurements. Tumor response was evaluated by comparing pre- and post-radiation tumor volumes using CT scan and MRI images. The mean osteopontin level was 0.49 ± 0.45 ng/mL and the mean percentage change in tumor volume was 8.59 ± 54.22%, with a 60% enlargement in tumor volume. A progressive disease was found in 26.7% of patients. There was a weak but insignificant negative correlation (<em>r</em> = -0.39, <em>p</em> = 0.146) between the level of osteopontin and radiation response. In contrast, there was a strong but insignificant positive correlation (<em>r </em>= +0.68, <em>p</em> = 0.219) between the level of osteopontin and radiation response in the patient group that used the chemosensitizer temozolamide.</p>

Repeatability of Three-Dimensional Computed Tomographic Volumetric Measurement of Lumbosacral Intervertebral Foramina in German Shepherd Dogs

2018 ◽  
Vol 31 (05) ◽  
pp. 339-343 ◽  
Author(s):  
Stefan Gordon ◽  
Janis Bridges ◽  
Susan Tomlin ◽  
Angela Hartman ◽  
Andrew Worth
Keyword(s):  
Three Dimensional ◽  
Clinical Signs ◽  
Volumetric Analysis ◽  
Lumbosacral Junction ◽  
Volumetric Measurement ◽  
German Shepherd ◽  
Computed Tomographic ◽  
Volume Measurements ◽  
The Mean ◽  
Intervertebral Foramina

Objectives This article determines the repeatability of a recently reported method of volumetric measurement of the lateral intervertebral neurovascular foramina at the lumbosacral junction in German shepherd dogs. Materials and Methods Batch files including the intervertebral neurovascular foramina were derived from previously obtained computed tomography studies of the extended lumbosacral junction of 20 German shepherd dogs and converted into volume datasets. Three observers independently performed five measurements of the left and right lumbosacral intervertebral neurovascular foramina in each dog, using an Extended Brilliance Workstation (Phillips, The Netherlands) to generate a volume of the lumbosacral intervertebral foramina in cubic millimetres, as described by Worth and colleagues in 2017. The inter-observer repeatability of the mean of the five-volume measurements (40 foramina) was assessed using the Bland–Altman limits of agreement method. One observer, blinded to the previous measurements, repeated the volumetric analysis on 20 lumbosacral intervertebral foramina for an assessment of intra-observer repeatability using the same statistical methods. Results This method of volumetric analysis showed good intra- and inter-observer repeatability with 95% of paired comparisons falling within two standard deviations of the mean difference between them. Clinical Significance This method of measuring the volume of the lumbosacral intervertebral neurovascular foramina is repeatedly reliable and may be a useful tool when testing the effects of motion and disease on the lumbosacral junction, and could help guide surgical intervention when foraminal narrowing is implicated in the clinical signs.

scholarly journals Three-dimensional changes in head shape after extended sagittal strip craniectomy with wedge ostectomies and helmet therapy

2017 ◽  
Vol 19 (6) ◽  
pp. 684-689 ◽  
Author(s):  
Pang-Yun Chou ◽  
Rami R. Hallac ◽  
Shitel Patel ◽  
Min-Jeong Cho ◽  
Neil Stewart ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Inclusion Criteria ◽  
Head Shape ◽  
Equal Distribution ◽  
3D Images ◽  
Dimensional Changes ◽  
End Of Treatment ◽  
Helmet Therapy ◽  
The Mean ◽  
Strip Craniectomy

OBJECTIVEOutcome studies for sagittal strip craniectomy have largely relied on the 2D measure of the cephalic index (CI) as the primary indicator of head shape. The goal of this study was to measure the 2D and 3D changes in head shape that occur after sagittal strip craniectomy and postoperative helmet therapy.METHODSThe authors performed a retrospective review of patients treated with sagittal strip craniectomy at their institution between January 2012 and October 2015. Inclusion criteria were as follows: 1) isolated sagittal synostosis; 2) age at surgery < 200 days; and 3) helmet management by a single orthotist. The CI was calculated from 3D images. Color maps and dot maps were generated from 3D images to demonstrate the regional differences in the magnitude of change in head shape over time.RESULTSTwenty-one patients met the study inclusion criteria. The mean CI was 71.9 (range 63.0–77.9) preoperatively and 81.1 (range 73.0–89.8) at the end of treatment. The mean time to stabilization of the CI after surgery was 57.2 ± 32.7 days. The mean maximum distances between the surfaces of the preoperative and 1-week postoperative and between the surfaces of the preoperative and end-of-treatment 3D images were 13.0 ± 4.1 mm and 24.71 ± 6.83 mm, respectively. The zone of maximum change was distributed equally in the transverse and vertical dimensions of the posterior vault.CONCLUSIONSThe CI normalizes rapidly after sagittal strip craniectomy (57.2 days), with equal distribution of the change in CI occurring before and during helmet therapy. Three-dimensional analysis revealed significant vertical and transverse expansion of the posterior cranial vault. Further studies are needed to assess the 3D changes that occur after other sagittal strip craniectomy techniques.

scholarly journals Rapid Estimation of Cabbage Head Volume across a Population Varying in Head Shape: A Test of Two Geometric Formulae

2004 ◽  
Vol 14 (3) ◽  
pp. 388-391 ◽  
Author(s):  
Theodore J.K. Radovich ◽  
Matthew D. Kleinhenz
Keyword(s):  
Agricultural Research ◽  
Three Dimensional ◽  
Head Shape ◽  
Water Displacement ◽  
Volume Measurements ◽  
Agricultural Research And Development ◽  
Ellipsoid Volume ◽  
Volume Estimates ◽  
Development Center ◽  
Direct Measures

Volume measurements are useful in crop quality management because they offer three-dimensional estimates of commodity size, which is often closely related to commodity weight and density. The objective of this study was to compare volume estimates calculated with the sphere and spherical ellipsoid volume formulae with direct measures of volume via water displacement across a population of cabbage (Brassica oleracea Capitata Group) heads varying widely in shape. A total of 157 heads with polar (P): equatorial (E) diameter ratios ranging between 0.5 (flat) to 2.1 (tall) were harvested at horticultural maturity from plants grown in 2002 and 2003 at the Ohio Agricultural Research and Development Center (OARDC) in Wooster, Ohio. The sphere formula underestimated volume in heads with P:E ratios <1 and overestimated volume in heads with P:E ratios >1. Use of the spherical ellipsoid formula reduced the shapedependency of volume estimates and was determined to be a valuable tool for the accurate, precise, and rapid measurement of head volume.

Electron Holographic Nano-Characterization of Gold Catalyst at Interface

2002 ◽  
Vol 727 ◽  
Author(s):  
S. Ichikawa ◽  
T. Akita ◽  
M. Okumura ◽  
M. Haruta ◽  
K. Tanaka
Keyword(s):  
Contact Angle ◽  
Titanium Oxide ◽  
Gold Catalyst ◽  
Three Dimensional ◽  
High Resolution Electron Microscopy ◽  
Electron Holography ◽  
Gold Particles ◽  
Oxide Support ◽  
The Mean ◽  
A Charge

AbstractThe catalytic properties of nanostructured gold catalyst are known to depend on the size of the gold particles and to be activated when the size decreases to a few nanometers. We investigated the size dependence of the three-dimensional nanostructure on the mean inner potential of gold catalysts supported on titanium oxide using electron holography and high-resolution electron microscopy (HREM). The contact angle of the gold particles on the titanium oxide tended to be over 90° for gold particles with a size of over 5 nm, and below 90° for a size of below 2 nm. This decreasing change in the contact angle (morphology) acts to increase the perimeter and hence the area of the interface between the gold and titanium oxide support, which is considered to be an active site for CO oxidation. The mean inner potential of the gold particles also changed as their size decreased. The value of the inner potential of gold, which is approximately 25 V in bulk state, rose to over 40 V when the size of the gold particles was less than 2 nm. This phenomenon indicates the existence of a charge transfer at the interface between gold and titanium oxide. The 3-D structure change and the inner potential change should be attributed to the specific electronic structure at the interface, owing to both the “nano size effect” and the “hetero-interface effect.”

The Influence of Blade Wakes on the Performance of Interturbine Diffusers

1996 ◽  
Vol 118 (2) ◽  
pp. 347-352 ◽  
Author(s):  
R. G. Dominy ◽  
D. A. Kirkham
Keyword(s):  
Performance Modeling ◽  
Three Dimensional ◽  
Secondary Flows ◽  
Two Dimensional ◽  
Correct Performance ◽  
Analysis Methods ◽  
Flow Factor ◽  
The Mean ◽  
Lp Turbine

Interturbine diffusers provide continuity between HP and LP turbines while diffusing the flow upstream of the LP turbine. Increasing the mean turbine diameter offers the potential advantage of reducing the flow factor in the following stages, leading to increased efficiency. The flows associated with these interturbine diffusers differ from those in simple annular diffusers both as a consequence of their high-curvature S-shaped geometry and of the presence of wakes created by the upstream turbine. It is shown that even the simplest two-dimensional wakes result in significantly modified flows through such ducts. These introduce strong secondary flows demonstrating that fully three-dimensional, viscous analysis methods are essential for correct performance modeling.

scholarly journals Overestimation of grey matter atrophy in glioblastoma patients following radio(chemo)therapy

2021 ◽  
Author(s):  
A. Gommlich ◽  
F. Raschke ◽  
J. Petr ◽  
A. Seidlitz ◽  
C. Jentsch ◽  
...  
Keyword(s):  
Brain Tumour ◽  
Contralateral Hemisphere ◽  
Mr Images ◽  
Segmentation Accuracy ◽  
Volume Measurements ◽  
Radiation Induced ◽  
The Mean ◽  
Changes Over Time ◽  
Grey Matter Atrophy ◽  
Abnormal Tissue

Abstract Objective Brain atrophy has the potential to become a biomarker for severity of radiation-induced side-effects. Particularly brain tumour patients can show great MRI signal changes over time caused by e.g. oedema, tumour progress or necrosis. The goal of this study was to investigate if such changes affect the segmentation accuracy of normal appearing brain and thus influence longitudinal volumetric measurements. Materials and methods T1-weighted MR images of 52 glioblastoma patients with unilateral tumours acquired before and three months after the end of radio(chemo)therapy were analysed. GM and WM volumes in the contralateral hemisphere were compared between segmenting the whole brain (full) and the contralateral hemisphere only (cl) with SPM and FSL. Relative GM and WM volumes were compared using paired t tests and correlated with the corresponding mean dose in GM and WM, respectively. Results Mean GM atrophy was significantly higher for full segmentation compared to cl segmentation when using SPM (mean ± std: ΔVGM,full = − 3.1% ± 3.7%, ΔVGM,cl = − 1.6% ± 2.7%; p < 0.001, d = 0.62). GM atrophy was significantly correlated with the mean GM dose with the SPM cl segmentation (r = − 0.4, p = 0.004), FSL full segmentation (r = − 0.4, p = 0.004) and FSL cl segmentation (r = -0.35, p = 0.012) but not with the SPM full segmentation (r = − 0.23, p = 0.1). Conclusions For accurate normal tissue volume measurements in brain tumour patients using SPM, abnormal tissue needs to be masked prior to segmentation, however, this is not necessary when using FSL.

scholarly journals Proximity of the middle meningeal artery and maxillary artery to the mandibular head and mandibular neck as revealed by three-dimensional time-of-flight magnetic resonance angiography

2021 ◽  
Author(s):  
Daphne Schönegg ◽  
Raphael Ferrari ◽  
Julian Ebner ◽  
Michael Blumer ◽  
Martin Lanzer ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Angiography ◽  
Three Dimensional ◽  
Time Of Flight ◽  
Middle Meningeal Artery ◽  
Individual Variability ◽  
Maxillary Artery ◽  
Condylar Process ◽  
The Mean ◽  
Meningeal Artery

Abstract Purpose The close topographic relationship between vascular and osseous structures in the condylar and subcondylar region and marked variability in the arterial course has been revealed by both imaging and cadaveric studies. This study aimed to verify the previously published information in a large sample and to determine a safe surgical region. Methods We analyzed the three-dimensional time-of-flight magnetic resonance angiography images of 300 individuals. Results The mean distance between the middle meningeal artery and the apex of the condyle or the most medial point of the condyle was 18.8 mm (range: 11.2–25.9 mm) or 14.5 mm (range: 8.8–22.9 mm) respectively. The course of the maxillary artery relative to the lateral pterygoid muscle was medial in 45.7% of cases and lateral in 54.3%. An asymmetric course was evident in 66 patients (22%). The mean distance between the maxillary artery and condylar process at the deepest point of the mandibular notch was 6.2 mm in sides exhibiting a medial course (range: 3.7–9.8 mm) and 6.6 mm in sides exhibiting a lateral course (range: 3.9–10.4 mm). The distances were significantly influenced by age, gender, and the course of the maxillary artery. Conclusion Our study emphasizes the marked inter- and intra-individual variability of the maxillary and middle meningeal arterial courses. We confirmed the proximity of the arteries to the condylar process. Extensive surgical experience and thorough preparation for each individual case are essential to prevent iatrogenic vascular injury.

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