THE ORIGIN OF TRIPLOIDY IN CHICK (GALLUS DOMESTICUS) EMBRYOS

1974 ◽  
Vol 16 (2) ◽  
pp. 317-322 ◽  
Author(s):  
S. J. Mong ◽  
M. D. Snyder ◽  
N. S. Fechheimer ◽  
R. G. Jaap
Keyword(s):  
High Frequency ◽  
Cytogenetic Analysis ◽  
Gallus Domesticus ◽  
Chick Embryos ◽  
Reciprocal Crosses ◽  
Younger Age ◽  
The Difference

Cytogenetic analysis was made of 1466 chick embryos at one day of incubation. The embryos were from reciprocal crosses of two genetically diverse stocks (G1) and from matings among resulting crossbreds (G2). The overall frequency of heteroploidy was 4.6% in G1 and 5.8% in G2. The difference was not significant but the difference in frequency of triploid embryos (0.5% and 3.1%) was significant. This difference was attributed to the younger age of dams of the group with high frequency of triploidy. Furthermore, the same group of dams produced more triploid embryos when commencing their laying cycle at 19-22 weeks of age than at subsequent ages, 23-27 weeks of age, when their laying cycle had stabilized. The gonosomic complement of 54 triploid embryos was 25 ZZZ: 22 ZWW: 7 ZZW, indicating that about 80% result from failure of meiosis II of oogenesis.

Comparison of In-the-Ear and Over-the-Ear Hearing Aid Fittings

1986 ◽  
Vol 51 (4) ◽  
pp. 362-369 ◽  
Author(s):  
Donna M. Risberg ◽  
Robyn M. Cox
Keyword(s):  
Hearing Aids ◽  
High Frequency ◽  
Comparative Evaluation ◽  
Speech Intelligibility ◽  
Hearing Aid ◽  
Hearing Aid Fitting ◽  
The Difference ◽  
Functional Gain ◽  
The Relationship

A custom in-the-ear (ITE) hearing aid fitting was compared to two over-the-ear (OTE) hearing aid fittings for each of 9 subjects with mild to moderately severe hearing losses. Speech intelligibility via the three instruments was compared using the Speech Intelligibility Rating (SIR) test. The relationship between functional gain and coupler gain was compared for the ITE and the higher rated OTE instruments. The difference in input received at the microphone locations of the two types of hearing aids was measured for 10 different subjects and compared to the functional gain data. It was concluded that (a) for persons with mild to moderately severe hearing losses, appropriately adjusted custom ITE fittings typically yield speech intelligibility that is equal to the better OTE fitting identified in a comparative evaluation; and (b) gain prescriptions for ITE hearing aids should be adjusted to account for the high-frequency emphasis associated with in-the-concha microphone placement.

Incidence of postural headache after lumbar puncture requiring epidural blood patch: Effects of needle caliber; 2-year experience

2021 ◽  
pp. 197140092110006
Author(s):  
Warren Chang ◽  
Ajla Kadribegic ◽  
Kate Denham ◽  
Matthew Kulzer ◽  
Tyson Tragon ◽  
...  
Keyword(s):  
Risk Factors ◽  
Lumbar Puncture ◽  
Conservative Management ◽  
Epidural Blood Patch ◽  
Female Gender ◽  
Regional Hospital ◽  
Younger Age ◽  
Blood Patch ◽  
History Of ◽  
The Difference

Purpose A common complication of lumbar puncture (LP) is postural headaches. Epidural blood patches are recommended if patients fail conservative management. Owing to a perceived increase in the number of post-lumbar puncture headaches (PLPHs) requiring epidural blood patches at a regional hospital in our network, the decision was made to switch from 20 to 22 gauge needles for routine diagnostic LPs. Materials and methods Patients presenting for LP and myelography at one network regional hospital were included in the study. The patients were contacted by nursing staff 3 days post-procedure; those patients who still had postural headaches after conservative management and received epidural blood patches were considered positive cases. In total, 292 patients were included; 134 underwent LP with 20-gauge needles (53 male, 81 female, average age 57.7) and 158 underwent LP with 22-gauge needles (79 male, 79 female, average age 54.6). Results Of 134 patients undergoing LP with 20-gauge needles, 15 (11%) had PLPH requiring epidural blood patch (11 female, 3 male, average age 38). Of 158 patients undergoing LP with 22-gauge needles, only 5 (3%) required epidural blood patches (all female, average age 43). The difference was statistically significant ( p < 0.01). Risk factors for PLPH included female gender, younger age, lower body mass index, history of prior PLPH and history of headaches. Conclusion Switching from 20-gauge to 22-gauge needles significantly decreased the incidence of PLPH requiring epidural blood patch. Narrower gauge or non-cutting needles should be considered in patients with risk factors for PLPH, allowing for CSF requirements.

scholarly journals Hyperfine structure in the arc spectrum of cæsium and nuclear rotation

1928 ◽  
Vol 121 (787) ◽  
pp. 432-447 ◽  
Keyword(s):  
Hyperfine Structure ◽  
Nuclear Spin ◽  
High Frequency ◽  
Principal Series ◽  
Very High Frequency ◽  
Nuclear Rotation ◽  
Higher Temperature ◽  
The Difference ◽  
Mechanical Moment ◽  
Very High

The arc spectrum of cæsium was investigated with the object of finding whether any of its lines possessed hyperfine structure, resulting from a nuclear magnetic moment, due to a quantised nuclear spin. The lines belonging to the principal series should, owing to the greater degree of penetration of the electron in the (1 s or 6 1 ) orbit, and the correspondingly greater interaction, show the greatest effect. The lines of the principal series are very easily broadened if the vapour pressure of the metal becomes high, so that great care had to be used in obtaining the spectrum of cæsium at a sufficiently low temperature. The most satisfactory method of excitation was found to be the application by means of external electrodes of a very high frequency alternating current to a tube filled with helium at about 2 mm. pressure containing a small quantity of cæsium. The tube required slight heating to bring out the cæsium lines; without this the helium spectrum was very much stronger than the metallic spectrum. At a very low vapour pressures of cæsium the discharge was blue in colour. Under these conditions the lines of the principal series showed no broadening greater than that due to thermal agitation, but at a slightly higher temperature the colour of the discharge became purple and the lines broadened. The lines belonging to the principal series were found to be very close doublets with very nearly constant frequencies differences. A theory is worked out which explains the origin of these doublets, assuming a nuclear spin of one half quantum; by correlating the difference in the separation of the hyperfine structure doublets in the 1 s — m 2 p 3/2 lines and the 1 s — m 2 p 1/2 lines, it is shown that a ratio of the magnetic to the mechanical moment of the nucleus about twice as great as the corresponding ratio for the electron would account for the observed frequency differences. The spectral notation used throughout is that of Hund. The results are compared with those found for the hyperfine structure of some of the bismuth lines by Back and Goudsmid, and are found to be in satisfactory agreement. A selection principle is found which applies both to the bismuth and the cæsium spectrum.

High-frequency seismic noise as a function of depth

1991 ◽  
Vol 81 (4) ◽  
pp. 1101-1114
Author(s):  
Jerry A. Carter ◽  
Noel Barstow ◽  
Paul W. Pomeroy ◽  
Eric P. Chael ◽  
Patrick J. Leahy
Keyword(s):  
New York ◽  
High Frequency ◽  
Seismic Noise ◽  
Low Frequency ◽  
Time Variability ◽  
Orthogonal Components ◽  
The Difference ◽  
Frequency Coherence ◽  
Cultural Noise ◽  
Natural Wind

Abstract Evidence is presented supporting the view that high-frequency seismic noise decreases with increased depth. Noise amplitudes are higher near the free surface where surface-wave noise, cultural noise, and natural (wind-induced) noise predominate. Data were gathered at a hard-rock site in the northwestern Adirondack lowlands of northern New York. Between 15- and 40-Hz noise levels at this site are more than 10 dB less at 945-m depth than they are at the surface, and from 40 to 100 Hz the difference is more than 20 dB. In addition, time variability of the spectra is shown to be greater at the surface than at either 335- or 945-m depths. Part of the difference between the surface and subsurface noise variability may be related to wind-induced noise. Coherency measurements between orthogonal components of motion show high-frequency seismic noise is more highly organized at the surface than it is at depth. Coherency measurements between the same component of motion at different vertical offsets show a strong low-frequency coherence at least up to 945-m vertical offsets. As the vertical offset decreases, the frequency band of high coherence increases.

Effect of Physico-chemical Characteristics of Raw Muscles from Three Iberian × Duroc Genotypes on Dry-cured Meat Products Quality

2007 ◽  
Vol 13 (6) ◽  
pp. 485-495 ◽  
Author(s):  
M.R. Ramirez ◽  
R. Cava
Keyword(s):  
Sensory Quality ◽  
Meat Products ◽  
Biceps Femoris ◽  
Raw Material ◽  
Meat Production ◽  
Reciprocal Crosses ◽  
Physico Chemical ◽  
Cured Meat ◽  
The Difference

The effect of raw material characteristics (longissimus dorsi and biceps femoris) on dry-cured loin and ham quality from three different Iberian · Duroc genotypes was studied: GEN1: ♂ Iberian · ♀ Duroc1, GEN2: ♂ Duroc1 · ♀ Iberian; GEN3: ♂ Duroc2 · ♀ Iberian. GEN1 and GEN2 are reciprocal crosses, while the difference between GEN2 and GEN3 is the Duroc sire line. The line Duroc1 (DU1) was selected for the manufacture of dry-cured meat products, whereas the line Duroc2 (DU2) was selected for meat production with low carcass fat. Raw material and dry-cured meat products did not differ between reciprocal crosses (GEN1 vs. GEN2). However, the genotype of the Duroc sire line affected the quality of meat and dry-cured meat products. GEN1 and GEN2 had higher adipogenic nature and higher postmortem pH than GEN3, and as a result, these dry-cured meat products had better instrumental and sensory quality than those from GEN3. By contrast, meat from GEN3 had lower pH, fat content, and oxidative stability which decreased the quality of dry-cured meat products. Therefore, there was a close connection between raw material and dry-cured meat products quality as it was affected by characteristics related to the genotype such as the adipogenic character and meat quality traits associated with pH.

scholarly journals Prevalence and diversity of ectoparasites in scavenging chickens (Gallus domesticus) and their association to body weight

2020 ◽  
Vol 21 (7) ◽  
Author(s):  
Edy Riwidiharso ◽  
Darsono Darsono ◽  
Endang ariyani Setyowati ◽  
Hery Pratiknyo ◽  
EMING SUDIANA ◽  
...  
Keyword(s):  
Body Weight ◽  
Rural Areas ◽  
Gallus Domesticus ◽  
Survey Method ◽  
Central Java ◽  
The Common ◽  
The Difference ◽  
The Relationship ◽  
The City ◽  
Regression Correlation

Abstract. Riwidiharso E, Darsono, Setyowati EA, Pratiknyo H, Sudiana E, Santoso S, Yani E, Widhiono I. 2020. Prevalence and diversity of ectoparasites in scavenging chickens (Gallus domesticus) and their association to body weight. Biodiversitas 21: 3163-3169. Domestic chickens (Gallus domesticus) which are traditionally fed by scavenging on farms predispose them to ectoparasites infestation. In this study, a preliminary survey was conducted on the common ectoparasites on G. domesticus in the rural areas of Banyumas. The purposes of this study were to determine the diversity of ectoparasites, their prevalence, and their relationship to the chickens body weight. This research was conducted by the survey method from December 2019 to April 2020 in five villages around the city of Purwokerto, Banyumas District, Central Java, Indonesia viz., Kedungwuluh, Kedungwringin, Kutasari, Karangsalam, and Karanggintung. Data analysis was conducted by Shannon Wiener and Evenness indexes. Analysis of variance was used to calculate the difference in prevalence among sample locations. Regression correlation analysis was used to determine the relationship between prevalence and chicken body weight. The results showed that there were six ectoparasite species  i.e., Menopon gallinae, Menacanthus cornutus, Lipeurus caponis, Dermanysus gallinae, Megninia ginglymura, and Haemaphysallis sp. parasitizing G. domesticus. The number of ectoparasite individuals among locations was significantly different (F 5.59 < 32.45; p <0.05). The most number of ectoparasite was found in Karangsalam (272 individuals). The most prevalent ectoparasite was M. cornutus (45%), followed by L. caponis (40%), and the lowest was M. synglineura (25%). Ectoparasite prevalence was associated with chicken weight loss (r = 0.98). The prevalence of ectoparasite of domestic chickens farm in the Banyumas Regency is classified as low but has the potential to influence body weight.

scholarly journals Age and sex variation in visceral adipose tissue

2019 ◽  
Vol 6 (1) ◽  
pp. 101
Author(s):  
Pallavi Panchu ◽  
Biju Bahuleyan ◽  
Rose Babu ◽  
Vineetha Vijayan
Keyword(s):  
Adipose Tissue ◽  
Visceral Fat ◽  
Metabolic Disorders ◽  
Age Groups ◽  
Fat Distribution ◽  
Age Group ◽  
Cross Sectional ◽  
Younger Age ◽  
The Difference ◽  
Gender Pattern

Background: Adipose tissue mainly visceral fat is said to be harmful and acts as a harbinger of metabolic disorders. A changing trend is seen in the recent decades with decreasing incidence of metabolic disorders in men even though visceral fat is said to be higher in them. Sex hormones may influence the deposition pattern of adipose tissue. The aim of this study was to observe effects of age on visceral fat and to know if the difference in gender pattern of fat distribution is maintained throughout life or disappears after menopause.Methods: This cross-sectional observational study was conducted in Thrissur on 385 apparently healthy subjects using Omron body composition analyser. Data was analysed using SPSS 20.0 version. The tests employed were NOVA, independent samples t-test.Results: In each age group, men had significantly higher visceral fat than females. As age increased, visceral fat increased significantly in both genders. In each group, except for younger age groups, VF levels were equal in men and women.Conclusions: Visceral fat is higher in men and this difference is seen in all age groups. As age increases, visceral fat levels also increased in men and women. The distribution of visceral fat is such that a greater number of men have high to very high levels at a younger age group, a feature observed in women only in the peri and post-menopausal age. Adoption of an active lifestyle coupled with healthy diet should protect against onset of metabolic disorders.

Nonword repetition and levels of abstraction in phonological knowledge

2006 ◽  
Vol 27 (4) ◽  
pp. 577-581 ◽  
Author(s):  
Benjamin Munson
Keyword(s):  
High Frequency ◽  
Low Frequency ◽  
Nonword Repetition ◽  
Chronological Age ◽  
Frequency Effect ◽  
Vocabulary Size ◽  
Levels Of Abstraction ◽  
Opposite Pattern ◽  
The Difference ◽  
Restriction Of Range

Susan Gathercole's Keynote Article (2006) is an impressive summary of the literature on nonword repetition and its relationship to word learning and vocabulary size. When considering research by Mary Beckman, Jan Edwards, and myself, Gathercole speculates that our finding of a stronger relationship between vocabulary measures and repetition accuracy for low-frequency sequences than for high-frequency sequences is due to differences in the range of the two measures. In our work on diphone repetition (e.g., Edwards, Beckman, & Munson, 2004; Munson, Edwards, & Beckman, 2005) we tried to increase the range in our dependent measures by coding errors on a finer grained scale than simple correct/incorrect scoring would allow. Moreover, restriction of range does not appear to be the driving factor in the relationship between vocabulary size and the difference between high- and low-frequency sequence repetition accuracy (what we call the frequency effect) in at least one of our studies (Munson et al., 2005). When the children with the 50 lowest mean accuracy scores for high-frequency sequences were examined, vocabulary size accounted for 10.5% of the variance in the frequency effect beyond what was accounted for by chronological age. When the 50 children with the highest mean accuracy scores for high-frequency sequences were examined (a group in which the range of high-frequency accuracy scores was more compressed, arguably reflecting ceiling effects), an estimate of vocabulary size accounted for only 6.9% of the frequency effect beyond chronological age. The associated β coefficient was significant only at the α<0.08 level. This is the opposite pattern than Gathercole's argument would predict.

scholarly journals Improved relapse recovery in paediatric compared to adult multiple sclerosis

Brain ◽  
2020 ◽  
Vol 143 (9) ◽  
pp. 2733-2741
Author(s):  
Tanuja Chitnis ◽  
Greg Aaen ◽  
Anita Belman ◽  
Leslie Benson ◽  
Mark Gorman ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Functional System ◽  
Progressive Multiple Sclerosis ◽  
Age Related ◽  
Younger Age ◽  
Disability Status ◽  
The Us ◽  
The Difference ◽  
Effect Of Age

Abstract Incomplete relapse recovery contributes to disability accrual and earlier onset of secondary progressive multiple sclerosis. We sought to investigate the effect of age on relapse recovery. We identified patients with multiple sclerosis from two longitudinal prospective studies, with an Expanded Disability Status Scale (EDSS) score within 30 days after onset of an attack, and follow-up EDSS 6 months after attack. Adult patients with multiple sclerosis (n = 632) were identified from the Comprehensive Longitudinal Investigations in Multiple Sclerosis at Brigham study (CLIMB), and paediatric patients (n = 132) from the US Network of Paediatric Multiple Sclerosis Centers (NPMSC) registry. Change in EDSS was defined as the difference in EDSS between attack and follow-up. Change in EDSS at follow-up compared to baseline was significantly lower in children compared to adults (P = 0.001), as were several functional system scores. Stratification by decade at onset for change in EDSS versus age found for every 10 years of age, EDSS recovery is reduced by 0.15 points (P &lt; 0.0001). A larger proportion of children versus adults demonstrated improvement in EDSS following an attack (P = 0.006). For every 10 years of age, odds of EDSS not improving increase by 1.33 times (P &lt; 0.0001). Younger age is associated with improved recovery from relapses. Age-related mechanisms may provide novel therapeutic targets for disability accrual in multiple sclerosis.

DIFFERENCE FREQUENCY HARMONIC ION HEATING

1967 ◽  
Vol 45 (5) ◽  
pp. 1771-1781 ◽  
Author(s):  
C. R. James ◽  
W. B. Thompson
Keyword(s):  
High Frequency ◽  
Collision Frequency ◽  
Difference Frequency ◽  
Fourth Power ◽  
Heating Process ◽  
Ion Heating ◽  
Frequency Signal ◽  
Transverse Waves ◽  
The Difference ◽  
Frequency Harmonic

The heating of a magnetized hot diffuse plasma using the difference frequency signal generated from two high-frequency (35 GHz) transverse waves is examined. The plasma is described by the cold plasma model and a series expansion of harmonics is used to obtain a solution to the equations. It is shown that the energy absorbed by the ions can be made inversely proportional to the collision frequency and the fourth power of the driven frequency and proportional to the fourth power of the driven electric field intensity. An investigation of the sensitivity of the heating process to fluctuations in frequency, density, and d-c. magnetic field is carried out.

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