scholarly journals The statistical estimation of molecular weights from normal and difference ultracentrifuge boundaries

1972 ◽  
Vol 128 (2) ◽  
pp. 389-402 ◽  
Author(s):  
Margaret A. McCallum ◽  
S. P. Spragg
Keyword(s):  
Boundary Data ◽  
Statistical Estimation ◽  
Mean Value ◽  
Sedimentation Velocity ◽  
Infinite Time ◽  
True Error ◽  
Molecular Weights ◽  
Low Concentrations ◽  
The Mean ◽  
Estimated Error

1. To determine molecular weights from boundary data taken from a sedimentation velocity experiment in an ultracentrifuge, the parameter s/D must be estimated. This can be obtained by using non-linear statistical methods to fit a mathematical model [the Fujita & MacCosham (1959) equation] to the results. 2. The statistical method chosen was the simplex method of Nelder & Mead (1965), which was found to be ideal for this problem. Internal errors were calculated at the end of the search for the minimum in the residuals, but in general these errors were found to not represent the overall true error of the experiment. 3. Calculations of molecular weights of myoglobin showed that instabilities at low concentrations of protein (less than 0.8mg/ml) disturbed the calculation of s/D. If 1% (w/v) sucrose was included in the solvent, these instabilities were decreased, and extrapolating to infinite time the linear function of s versus 1/(time) gave an acceptable value for s with an error of ±4.8%. The estimates of the molecular weights were less well-defined and the mean value was low by 8%, with an estimated error of the mean of ±3%. The conclusion was that vibration was responsible for the instabilities without sucrose. 4. The Fujita–MacCosham equation can be extended to make it possible to estimate ratios of sedimentation and molecular weights for difference boundaries. Tests using two solutions of orosomucoid in which a 2% decrease in velocity of one boundary was achieved by adding a calculated quantity of sucrose showed that the analysis gave realistic values for the two ratios, and the error for the ratio of sedimentation coefficients was ±10%. The error was larger for the estimated ratio of the molecular weights, but the analysis gave the expected value for the ratio.

The Analysis of Different Stochastic Patterns during Loading in Plastic Area Using DIC Method

2014 ◽  
Vol 611 ◽  
pp. 490-495
Author(s):  
Martin Schrötter ◽  
Martin Hagara ◽  
Matúš Kalina
Keyword(s):  
Digital Image Correlation ◽  
Digital Image ◽  
Correlation Method ◽  
Mean Value ◽  
Image Correlation ◽  
Black And White ◽  
Unloaded State ◽  
Measured Deformation ◽  
The Mean ◽  
Estimated Error

The aim of this article is to present the influence of stochastic pattern on results accuracy of digital image correlation method in plastic areas. The various types of stochastic patterns were applied on testing specimens which were then tensioned. There was correlated the intensity of black and white color (denoted as grey value) dispersed on a specimen, then the mean value of estimated error for unloaded state as well as state of highest measured deformation and finally the amount of non-correlated facets. Also the maximal deformation of specimens was compared by which the damage of stochastic pattern emerged.

Transfer of aflatoxins from naturally contaminated feed to milk of Nili-Ravi buffaloes fed a mycotoxin binder

2016 ◽  
Vol 56 (10) ◽  
pp. 1637 ◽  
Author(s):  
N. Aslam ◽  
I. Rodrigues ◽  
D. M. McGill ◽  
H. M. Warriach ◽  
A. Cowling ◽  
...  
Keyword(s):  
Aflatoxin B1 ◽  
High Performance ◽  
Mean Value ◽  
Aflatoxin M1 ◽  
Enzyme Linked Immunosorbent Assay ◽  
Treatment Groups ◽  
Low Concentrations ◽  
Daily Concentration ◽  
The Mean ◽  
Carry Over

The objectives of this study were to observe the extent of transfer of aflatoxin B1 in feed to the aflatoxin M1 metabolite in milk in Nili-Ravi buffaloes and to evaluate the efficacy of a commercial mycotoxin binder (Mycofix, Biomin Singapore) incorporated into feed to minimise this transfer. Multiparous animals (n = 28) were randomly distributed to four groups corresponding to two treatments each with two levels of aflatoxin B1. Individual animals were exposed to naturally contaminated feed providing a total of 1475 µg/day (Groups A and B) or 2950 µg/day (Groups C and D) of aflatoxin B1. Groups B and D were given 50 g of mycotoxin binder daily mixed with feed whereas Groups A and C were kept as controls. Feed samples were analysed by reverse phase high performance liquid chromatography for aflatoxin B1 and milk samples were evaluated by enzyme-linked immunosorbent assay for the liver metabolite aflatoxin M1. The mean value of total daily aflatoxin M1 excretion for animals fed 2950 µg/day of aflatoxin B1 (112.6 µg/day) was almost double (P < 0.001) than the excretion in buffaloes fed 1475 µg/day (62.2 µg/day). The mean daily concentration of aflatoxin M1 in milk of animals from both treatment groups supplemented with 50 g/day of mycotoxin binder was 76.5 µg/day, nearly 22 µg lower than those without binder at 98.3 µg/day (s.e.d. = 5.99: P < 0.01). The interaction of binder and treatment was not significant i.e. the 50 g/day of binder was able to sequester aflatoxin B1 with the same efficiency in groups fed with high and low concentrations of aflatoxin B1. Carry over was (3.44%) lower (P = 0.001) in animals supplemented with 50 g/day of mycotoxin binder than those fed no binder (4.60%). Thus buffaloes are highly efficient at transferring aflatoxins in feed to the aflatoxin M1 metabolite in milk, whereas mycotoxin binder is capable of alleviating without preventing this contamination risk.

PROGESTERONE RECEPTORS IN THE RAT UTERUS: VARIATIONS IN CYTOSOL AND NUCLEI DURING THE OESTROUS CYCLE AND PREGNANCY

1978 ◽  
Vol 76 (1) ◽  
pp. 43-48 ◽  
Author(s):  
M. T. VU HAI ◽  
F. LOGEAT ◽  
E. MILGROM
Keyword(s):  
Binding Sites ◽  
Total Concentration ◽  
Progesterone Receptors ◽  
Mean Value ◽  
Oestrous Cycle ◽  
Small Peak ◽  
Low Concentrations ◽  
The Mean ◽  
High Level ◽  
Very High

SUMMARY The concentration of progesterone receptors in rat uterine cytosol and nuclei was measured during the oestrous cycle and pregnancy. The method used allowed the measurement of the total concentration of binding sites (unbound and hormone-bound). During the oestrous cycle, the concentration of receptors in the cytosol peaked at pro-oestrus, low concentrations were observed at oestrus and metoestrus, and an increase was seen at dioestrus. In the nuclei, maximum concentrations occurred at pro-oestrus and dioestrus. The number of receptors in the cytosol was very low during the first half of pregnancy, but the concentration increased progressively after day 15 to attain a very high level (about 26 000 binding sites/cell) on day 22. In the nuclei, the concentration of receptors was low at the beginning of pregnancy. On day 5 (day of implantation) there was a slight increase, which corresponded to a decrease in the number of cytosolic receptors and a small peak in the level of progesterone in the plasma. Maximum concentrations were attained during a 'plateau' period between days 9 and 15. Thereafter, there was a decrease in the concentration of nuclear receptors and on day 22, the mean value was very low; in some animals, probably on the verge of parturition, no receptors were detectable in the nuclei.

scholarly journals Prevalence of Anti-Neu5Gc Antibodies in Patients with Hypothyroidism

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Phaedra Eleftheriou ◽  
Stavros Kynigopoulos ◽  
Alexandra Giovou ◽  
Alexandra Mazmanidi ◽  
John Yovos ◽  
...  
Keyword(s):  
General Population ◽  
Mean Value ◽  
Antibody Concentration ◽  
Igg Antibodies ◽  
Autoimmune Hypothyroidism ◽  
Hashimoto’S Disease ◽  
Low Concentrations ◽  
Patient Groups ◽  
The Mean ◽  
Hashimoto's Disease

Background. N-Glycolylneuraminic acid (Neu5Gc) is a sialic acid synthesized by animals, but not by humans or birds. However, it can be incorporated in human cells and can trigger immune response. In the present study, we detected anti-Neu5Gc antibodies in samples of the general population and of patients suffering from hypothyroidism/Hashimoto’s disease, which is known to have autoimmune origin.Methods. Antibodies were measured using enzyme-immunosorbent techniques.Results. Serum anti-Neu5Gc IgG antibodies were higher in patients with hypothyroidism (mean: 14.8±15.9 μg/mL, median: 10.0 μg/mL,P=0.0003, Mann-Whitney) and even higher in the group with Hashimoto’s thyroiditis (mean: 31.1±16.3 μg/mL, median: 27.2 μg/mL,P=0.0000, Mann-Whitney) compared to the general population (mean: 5.3±4.7 μg/mL, median : 4 μg/mL). All anti-TPO positive samples had anti-Neu5Gc antibody concentration higher than the mean value of the general population while anti-TPO concentration was increased as anti-Neu5Gc concentration increased. Low concentrations of IgA and IgM antibodies were measured in both general population and patient groups.Conclusion. The increased values of anti-Neu5Gc antibodies in patients with hypothyroidism/Hashimoto’s disease and the correlation of anti-TPO incidence with increased anti-Neu5Gc concentration raise the possibility of an association between anti-Neu5Gc antibody development and autoimmune hypothyroidism.

Long-period modulated superstructures in Pd-12.5 at.%Ce and Pd-15 at.%Ce alloys

1990 ◽  
Vol 48 (4) ◽  
pp. 164-165
Author(s):  
Noriyuki Kuwano ◽  
Masaru Itakura ◽  
Kensuke Oki
Keyword(s):  
Electron Microscopy ◽  
Mean Value ◽  
Heavy Elements ◽  
Arc Furnace ◽  
X Ray ◽  
Long Period ◽  
Ultra High Purity ◽  
Heat Treated ◽  
Atomic Scattering ◽  
The Mean

Pd-Ce alloys exhibit various anomalies in physical properties due to mixed valences of Ce, and the anomalies are thought to be strongly related with the crystal structures. Since Pd and Ce are both heavy elements, relative magnitudes of (fcc-fpd) are so small compared with <f> that superlattice reflections, even if any, sometimes cannot be detected in conventional x-ray powder patterns, where fee and fpd are atomic scattering factors of Ce and Pd, and <f> the mean value in the crystal. However, superlattices in Pd-Ce alloys can be analyzed by electron microscopy, thanks to the high detectability of electron diffraction. In this work, we investigated modulated superstructures in alloys with 12.5 and 15.0 at.%Ce.Ingots of Pd-Ce alloys were prepared in an arc furnace under atmosphere of ultra high purity argon. The disc specimens cut out from the ingots were heat-treated in vacuum and electrothinned to electron transparency by a jet method.

Partition Coefficient Ratios and Tumour Perfusion Studied with 85mKr and 133Xe

1987 ◽  
Vol 26 (06) ◽  
pp. 253-257
Author(s):  
M. Mäntylä ◽  
J. Perkkiö ◽  
J. Heikkonen
Keyword(s):  
Partition Coefficient ◽  
Partition Coefficients ◽  
Regional Blood Flow ◽  
Blood Perfusion ◽  
Compartmental Analysis ◽  
Malignant Tumour ◽  
Mean Value ◽  
Perfusion Rate ◽  
Biological Variables ◽  
The Mean

The relative partition coefficients of krypton and xenon, and the regional blood flow in 27 superficial malignant tumour nodules in 22 patients with diagnosed tumours were measured using the 85mKr- and 133Xe-clearance method. In order to minimize the effect of biological variables on the measurements the radionuclides were injected simultaneously into the tumour. The distribution of the radiotracers was assumed to be in equilibrium at the beginning of the experiment. The blood perfusion was calculated by fitting a two-exponential function to the measuring points. The mean value of the perfusion rate calculated from the xenon results was 13 ± 10 ml/(100 g-min) [range 3 to 38 ml/(100 g-min)] and from the krypton results 19 ± 11 ml/(100 g-min) [range 5 to 45 ml/(100 g-min)]. These values were obtained, if the partition coefficients are equal to one. The equations obtained by using compartmental analysis were used for the calculation of the relative partition coefficient of krypton and xenon. The partition coefficient of krypton was found to be slightly smaller than that of xenon, which may be due to its smaller molecular weight.

Detection of Soluble Fibrin Monomer Complexes in Blood by Means of Protamine Sulphate Test

1968 ◽  
Vol 20 (01/02) ◽  
pp. 044-049 ◽  
Author(s):  
B Lipiński ◽  
K Worowski
Keyword(s):  
Human Subjects ◽  
Coronary Thrombosis ◽  
Mean Value ◽  
Healthy Human ◽  
Protamine Sulphate ◽  
Soluble Fibrin ◽  
Fibrin Monomer ◽  
Dog Plasma ◽  
The Mean ◽  
Precipitable Protein

SummaryIn the present paper described is a simple test for detecting soluble fibrin monomer complexes (SFMC) in blood. The test consists in mixing 1% protamine sulphate with diluted oxalated plasma or serum and reading the optical density at 6190 Å. In experiments with dog plasma, enriched with soluble fibrin complexes, it was shown that OD read in PS test is proportional to the amount of fibrin recovered from the precipitate. It was found that SFMC level in plasma increases in rabbits infused intravenously with thrombin and decreases after injection of plasmin with streptokinase. In both cases PS precipitable protein in serum is elevated indicating enhanced fibrinolysis. In healthy human subjects the mean value of OD readings in plasma and sera were found to be 0.30 and 0.11, while in patients with coronary thrombosis they are 0.64 and 0.05 respectively. The origin of SFMC in circulation under physiological and pathological conditions is discussed.

Detection of Circulating Tissue Factor and Factor VII in a Normal Population

1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Normal Population ◽  
Mean Value ◽  
Factor Vii ◽  
Significant Difference ◽  
Age Dependent ◽  
The Mean ◽  
Highly Correlated ◽  
And Gender

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.

Determination of Plasminogen in Clots and Thrombi

1966 ◽  
Vol 16 (01/02) ◽  
pp. 038-050 ◽  
Author(s):  
Ulla Hedner ◽  
Inga Marie Nilsson ◽  
B Robertson
Keyword(s):  
Mean Value ◽  
Main Mechanism ◽  
Clot Lysis ◽  
Post Mortem ◽  
Digestion Time ◽  
Normal Volunteers ◽  
Casein Solution ◽  
The Mean

SummaryThe plasminogen content was determined by a casein method in plasma and serum from 20 normal volunteers. The mean plasminogen content was found to be 10.1 ACU (the arbitrary caseinolytic unit defined in such a way that using a 3% casein solution and a digestion time of 20 min. at 37°C, 10 ACU gave an extinction of 0.300). No difference between serum and plasma regarding the plasminogen content was found.Plasminogen was determined in drained and drained plus washed clots prepared from 2 ml plasma. The highest values found in the drained clots were 0.9 ACU/clot and 0.2 ACU/clot in the drained plus washed clots.Plasminogen was also determined in drained and drained plus washed clots prepared from plasma with added purified plasminogen. The plasminogen was recovered in the washing fluid. According to these tests, then, purified added plasminogen is washed out of the clots.The plasminogen content of 20 thrombi obtained post mortem was also determined. The mean value was found to be 0.7 ACU/cm thrombus. Judging from our results, the “intrinsic clot lysis theory” is not the main mechanism of clot dissolution.

Perbedaan Pengetahuan Siswa Tentang Penyakit Hepatitis A Sebelum Dan Sesudah Penyuluhan Di MTsN 02 Bondowoso Tahun 2015

2017 ◽  
Vol 4 (2) ◽  
pp. 14
Author(s):  
Putri Megasari
Keyword(s):  
Hepatitis A ◽  
Hepatitis Virus ◽  
Sampling Technique ◽  
Mean Value ◽  
Test Design ◽  
The World ◽  
Before And After ◽  
Post Test ◽  
The Mean ◽  
Paired T Test

Hepatitis has become a health problem in the world. The hepatitis virus infected many people. According to the teacher of MTsN 02 Bondowoso more than 20 students have hepatitis A viral infection. The purpose of this research was to know the differences of students' knowledge about hepatitis A before and after counseling in MTsN 02 Bondowoso 2015. This study used pre-experimental (pre-post test design). This study used stratified random sampling technique, 127 students from 270 sample involved this research,and 143 students was excluded. We used questionnaires to collect data. The results showed that the mean value of the students 'knowledge about hepatitis A before counseling in MTsN 02 Bondowoso 2015 was 83.96 with the lowest value of 37.5 and the highest value was 100. The mean value of the students' knowledge about hepatitis A after counseling in MTsN 02 Bondowoso 2015 was 93.21 with the lowest value waf 62.5 and the highest value was 100. Paired t test showed that t (-9.07) > t table (1.98), the null hypothesis (H0) was rejected. There was a difference between students' knowledge about hepatitis A before and after counseling in MTsN 02 Bondowoso 2015. This study showed that routine counseling by healthcare provider was important to prevent hepatitis A infection.; Keywords: counseling, knowledge of students, hepatitis

Sign in / Sign up

Export Citation Format

Share Document