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1
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Influence of Transitional Metals Doping on Conductivity of Collagen Lyophilisate and Elastin

100%
Gauza M., Kubisz L.
Acta Physica Polonica A
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2012
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vol. 121
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issue 1A
A-65-A-67
EN
Knowing that conductivity is a temperature function σ = f(T) allows us to estimate the thermal stability of collagen preparations from fish skin. Measurements can provide information, which is crucial for technologies applying this type of collagen. Conductivity σ measurements were performed in a constant electric field E = 1 kV/m, in the temperature range of 290-480 K. White collagen lyophilisate was used as control material. It contained neither elastin nor melanin dopants nor non-organic dopants such as gold, copper, silver or zinc. Gold, copper, silver and zinc belong to the group of transitional metals and they have intermediate properties of both alkaline metals and metals in the p block of the periodic table. The common feature of most of these elements is their ability to form coordination complexes of intense color. In the measured materials peaks were found in the temperature range of 303-323 K. Peak temperature and its shape depend on the type of material. In the case of nano-gold doping a drop in peak temperature and a decrease in conductivity were observed. The measured materials are characterized by lower thermal resistance than bovine collagen. Nevertheless, thermal stability of fish skin collagen is high enough for fish skin collagen to replace bovine collagen. The measurement results obtained for white collagen and white collagen with Zn^{2+} may indicate better bonding of free water. The presence of nano-silver and nano-copper as doping agents in graphite collagen may lead to a decrease in hygroscopy of the material and, as a result, may increase its resistance to bacteria.
2
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Electrical Conductivity of Fish Skin Collagen in the Temperature Range 290-380 K

100%
Gauza M., Kubisz L.
Acta Physica Polonica A
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2010
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vol. 118
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issue 1
54-57
EN
Collagen is the major biopolymer of a living organism, which physical properties depend on water content. The observed transmission of spongiform encephalophaties (BSE) to humans resulted in the development of new sources of collagen. Fish skin seems to be one of such safe sources of collagen. Measurements of electrical conductivity as a function of temperature provides information, among other things, on the water release process. Experiment was carried out for fish skin (FSC) collagen (type I) and bovine Achilles tendon collagen (type I). Each sample was heated two times. Current-voltage characteristic was determined for FSC collagen to determine the range, within which the relation is linear. The primary differences appeared to be in electric conductivity, which was higher for FSC collagen than for BAT collagen. Electric conductivity varied from 10^{-6} S/m to 10^{-10} S/m depending on material and temperature. The process of free and bound water release was manifested as a peak on electrical conductivity-temperature curve between 320-350 K. The activation energy of the charge conduction process, determined on the basis of the Arrhenius plot, was material dependent and considerably higher for FSC collagen.
3
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DC Electrical Conductivity in Studies on Solid-State Proteins

100%
Kubisz L., Hojan-Jezierska D.
Acta Physica Polonica A
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2010
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vol. 118
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issue 1
103-105
EN
In structural studies on biological materials, among other methods, electrical techniques are used widely. Temperature dependence of electrical conductivity is a method permitting studies on denaturation, glass transition and water release - processes, which occur in solid-state proteins. Variations of amplitude and temperature of the peak on the recorded thermogram make it possible to draw conclusions about thermal stability and physicochemical processes occurring in the studied biological material. The shape of experimental curve is material-related and depends upon its "history". The paper is based on experimental results obtained mainly for collagen.
4
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Preliminary Analysis of Size Distribution of Objects Suspended in Normal Cerebrospinal Fluid in Case of Venticular Hydrocephalic Enlargement and Internal Hydrocephalus

81%
Staroń W., Kubisz L., Herbowski L.
Acta Physica Polonica A
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2012
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vol. 121
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issue 1A
A-46-A-48
EN
The paper presents preliminary analysis of normal non-coloured cerebrospinal fluid obtained from patients diagnosed due to suspicion of cerebrospinal fluid malabsorption. According to the findings, the normal cerebrospinal fluid was classified into two groups: A - with clinical diagnosis of ventricular hydrocephalic enlargement and B - with clinical diagnosis of internal hydrocephalus. The analysis of microscopic pictures of normal cerebrospinal fluid in both groups according to numbers and sizes of suspended objects was performed with the aid of Eclipse 600 microscope (with magnification of 1200×) working with a computer by a digital video camera. The authors observed that there is a significant difference in a shape of the distribution curve of objects' diameters between groups A and B. The maximum number of objects in group A was recorded within the range from 5 to 10 μm in diameter size whereas in group B the maximum was recorded within the range from 0.5 to 5 μm in diameter size.
5
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Posture Stability Evaluation Using Static Posturography in Patients after Cruciate Ligament Reconstruction

81%
Kubisz L., Werner H., Bosek M., Weiss W.
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issue 6A
957-960
EN
Ligament reconstruction is one of the surgical methods for treatment of anterior cruciate ligament injury. The main purpose of rehabilitation after surgical ligament reconstruction is to obtain maximal efficiency of knee joint, their stability and appropriate lower limbs encumbrance. Static posturography is one of the control, rehabilitative and diagnostic tools in such treatment. The purpose of the study was to evaluate the posture stability differences between healthy people and patients after anterior cruciate ligament reconstruction. The centre of pressure sway was registered using the standard posturography platform (Pro-med). During the test, the subject stood freely with eyes open and closed. In order to determine the stability of the subject, the average velocity of the centre of pressure sway, and the average accretion rate of surface area encircled by centre of pressure, a mean radius of centre of pressure and amount of its displacement were calculated. Parameters measured for the eyes closed posture were significantly greater for people after anterior cruciate ligament reconstruction, while differences between groups for eyes open test were statistically insignificant. This indicates impairment of the somatosensoric posture control system. It should be noted that selected stability indicators: an average velocity of the centre of pressure sway, its anterior-posterior and mediolateral components, a mean radius of centre of pressure and a mean accretion rate of surface area encircled by centre of pressure varied in both groups.
6
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Fourier Transform Near Infrared Raman Spectroscopy in Studies on Connective Tissue

61%
Połomska M., Kubisz L., Kalawski R., Oszkinis G., Filipiak R., Mazurek A.
Acta Physica Polonica A
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2010
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vol. 118
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issue 1
136-140
EN
Studies of tissue such as bones and veins often are carried out by means of microscopic and ultrasonographic methods. Therefore studies of changes caused by pathological or physical factors often are limited to morphological level. Application of Raman spectroscopy permits to associate morphological changes and molecular changes. The paper presents preliminary studies of temperature and ionizing radiation effects on Raman spectra of bone and collagen. Furthermore, effects of pathological factors on Raman spectra of human veins had been studied. It was noticed that heating of bone collagen up to 110°C gives the reversible changes in spectra. In the case of γ-irradiation, any effects were observed up to the dose of 1 MGy on mineral component of bone, whereas the influence on collagen was observed for doses higher than 100 kGy. The Raman spectra of varicose vs. normal veins permit to conclude some important changes observed for veins from chronic venous insufficiency patients.
7
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Effect of Low Frequency Magnetic Field on Germination of Onion (Allium cepa L.) Seeds

61%
Kubisz L., Hołubowicz R., Gauza M., Li H., Hojan-Jezierska D., Jaroszyk F.
Acta Physica Polonica A
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2012
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vol. 121
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issue 1A
A-49-A-53
EN
Commercial seed lots of onion (Allium cepa L.) of the cultivars "Octavia" and "Eureka" were soaked for 12 h in water of the temperature 20°C, then they were exposed to low frequency magnetic field (20 mT) for 10, 30, and 60 min. The field was generated using a standard device for magnetic stimulation VIOFOR JPS applied in human medical treatment. Next, the seeds were evaluated for energy and capacity of germination, length of the received germs as well as fresh masses of the obtained seedlings using the routine methods recommended by the International Seed Testing Association. For the seeds of the cultivar "Octavia", the field did not affect the energy of germination, however it did improve in all tested treatments their germination capacity. In the best of them (60 min), the germination capacity increased by 4.6%. For the seeds of the cultivar "Eureka", the tested field increased their energy of germination, which improves evenness of plants emergences in the field and has a significant importance for horticultural practice. When the seeds were exposed to the field for 60 min, their germination energy increased from 40% (control) to 63%. This result was accompanied by no differences in both length of germs and fresh masses of the received from them seedlings.
8
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Effect of ELF Magnetic Stimulation on Distortion Product of Otoacoustic Emission in Tinnitus Patients

61%
Pankowska M., Hojan-Jezierska D., Skrodzka E., Szymiec E., Kubisz L., Świdziński T., Wicher A.
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issue 6A
1035-1039
EN
One of the methods for objective evaluation of the hearing system is based on acoustic otoemissions. Particularly promising is the method based on measurement of the distortion product of otoacoustic emission as it is connected to the problem of tinnitus. Slow-varying magnetic field of low induction has been used in therapy of many diseases and ailments. It is expected that magnetostimulation will be effective in treatment of certain types of tinnitus by inducing the return of the organism to homeostasis. The aim of this study was to identify the changes in distortion product of otoacoustic emission levels in patients, prior and after the magnetostimulation. However any significant changes were found among patients with tinnitus, for the control group statistically important changes in distortion product of otoacoustic emission levels were observed.
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