Wyniki wyszukiwania - Biblioteka Nauki

1

Wywiad nt. perspektyw budownictwa mieszkaniowego

100%

Zaraska W.

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tom R. 36, nr 1

5-6

2

Design and implementation of a computerised remote alerting system for disabled people

72%

Zaraska K. , Zaraska W.

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2005

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tom Vol. 9

247--252

EN

We describe a remote alerting system for disabled people. The purpose of the system is to enable a monitored person to easily request medical assistance by pressing a single button on a wearable transmitter device. It should be noted that the handicapped person does not need to take any other action, such as picking up the phone. Upon triggering, the system is capable of automatically alerting the medical personnel, indicating the location of the alert using a digital transmission system or a speech synthesis module. Our system operates using primarily telephone links of any kind (PSTN, GSM, etc.). The system is intended for use by older or disabled people living alone, who may suddenly require immediate medical assistance, in particular, the people with physical disabilities and cardiovascular diseases.

3

Nowe, grubowarstwowe, hybrydowe, inteligentne czujniki temperatury przepływu

58%

Hodorowicz S. , Gondek J. J. , Cież M. , Zaraska W.

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1998

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tom nr 10

25-28

4

Piezopolimerowy generator mikromocy – analiza napięć w różnych konstrukcjach urządzenia

58%

Klimiec E. , Zaraska K. , Zaraska W.

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tom R. 85, nr 11

171-174

PL

Energię mechaniczną pochodzącą z chodzenia przetwarzano na energię elektryczną za pomocą piezopolietylenu o grubości 40 [mikro]m, umieszczonego we wkładce do obuwia. W artykule przeanalizowano zależność napięcia i uzyskanej mocy a także udział składowych harmonicznych w widmie mocy od konstrukcji generatora. Wprowadzenie elementu sprężynującego do konstrukcji wkładki pozwoliło na 30 krotne zwiększenie wartości mocy uzyskanej z folii tego samego materiału piezoelektrycznego.

EN

Mechanical energy from walking was converted into electrical energy using a 40 [mikro]m piezopolyethyene layer, placed inside a shoe insole. We analyze the relationship between the generator layout and obtained power, voltage and harmonic content of the generated signal. We find that placing an additional spring element inside the insole allows us to increase the generated power by a factor of 30, for the same piezoelectric material.

5

Badania właściwości piezoelektrycznych folii z politereftalanu etylenu PET pod kątem jej zastosowania na sensory ściskania i rozciągania

58%

Klimiec E. , Zaraska W. , Kuczyński S.

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tom R. 87, nr 10

68-71

PL

W artykule przedstawiono sposób polaryzacji i prowadzenia badań właściwości piezoelektrycznych folii z PET o grubości 100 μm dużej wytrzymałości mechanicznej i odporności chemicznej, pod kątem jej zastosowania na sensory ściskania i rozciągania. Trwałość otrzymanego elektretu badano za pomocą TSDC. Uzyskane wartości napięć piezoelektrycznych, a także długie czasy relaksacji wskazują, że badany materiał można zastosować na piezoelektryczne czujniki ściskania i rozciągania.

EN

Article presents polarization and piezoelectric properties investigation methods for 100� μm PET film, from a certain angle of its application as stretching and compresion sensors. This film has large mechanical strength and is chemically resistant. The durability of recived electret was investigated by TSDC method. Obtained piezoelectric voltage and relaxation time shows, that investigated material can be applied as piezoelectric stretching and compression sensors.

6

Zastosowanie folii PVDF w czujnikach wad postawy : model napięciowy i ładunkowy

58%

Klimiec E. , Piekarski J. , Zaraska W.

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tom Vol. 53, nr 12

130-132

PL

W artykule omówiono badania czujników z piezoelektrycznej folii z polifluorku winylidenu (PVDF) pod kątem ich zastosowania w systemie do pomiaru rozkładu nacisku stopy na podłoże w warunkach dynamicznych. Pod względem wytrzymałości mechanicznej, folia ta dobrze znosi warunki jakie panują w bucie w trakcie chodzenia, natomiast wadą tego materiału w omawianym zastosowaniu jest wysoki współczynnik piroelektryczny dla podczerwieni. Chcąc zapewnić prawidłowość i powtarzalność pomiarów przeprowadzono badania układów pomiarowych, napięciowego i ładunkowego z układem zerującym, oraz ładunkowego z górnoprzepustowym filtrem RC o częstotliwości odcięcia 0,08 Hz. Do zastosowania w systemie pomiarowym wad postawy wybrano układ ładunkowy z filtrem, o czym zadecydowały jego cechy eksploatacyjne.

EN

The article presents the results of a research about application of the sensors made from PVDF piezoelectric film for measuring the dynamic foot pressure distribution. The material is durable and capable of withstanding extreme conditions prevailing in the shoe during walking, but the material has got a high infrared piroelectric coefficient, and it is a serious fault in described application. To ensure correctness and repeatability of the results, the tests were conducted on two devices - one based on voltage follower and second based on charge amplifier, both with resetting device. Thanks to the better results the latter one has been selected for measurement of postural defects. An RC filter with the cutoff frequency of 0.08 Hz was added to reduce effects of the piroelectric factors.

7

Electroactive polymers : harvesting energy from walking

51%

Klimiec E. , Zaraska W. , Gąsiorowski K. , Sadowski T. , Pajda M.

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2008

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tom Vol. 49, nr 2

68-71

EN

Piezoelectric polymers film materiał allows for the conversion of mechanical energy applied to the materiał into electrical energy that can be used for supplying energy to electronic devices. While this method does not allow obtaining large useful power, recent advances in electronic technology, in particular wide availability of submicron low-power CMOS processes, have madę feasible the idea of using EAPs as power converters for human powered electronics. This concept allows to overcome the necessity of using battery as a power source, which is one of the main obstacles to widespread adoption of wearable computing devices. Of particular interest is harvesting energy from walking, which can be achieved by using an EAP shoe insole. This is presented in this paper. Maximum power has been calculated that can be drawn from walking energy owing to application of an PP-PE piezoelectric element. The amount of electric energy obtained from a PE-PP foil of a thickness of 11,5 µm for a single step of a duration of 1 s - that is equivalent to a frequency of 1 Hz - amounts to 340 nJ.

PL

Za pomocą polimerowych warstw piezoelektrycznych można przeprowadzić konwersję energii mechanicznej w energię elektryczną, która zasili urządzenia elektroniczne. Mimo że uzyskiwana w ten sposób moc nie jest duża, nowe osiągnięcia w dziedzinie technologii CMOS umożliwiają zastosowanie elektroaktywnych polimerów (EAP) jako przetworników energii pochodzącej z ruchu człowieka w energię elektryczną zasilającą urządzenia. Umożliwia to wyeliminowanie baterii jako źródła zasilania, co rozwiązuje jeden z głównych problemów w rozwoju komputerowej elektroniki przenośnej. Szczególnie interesujące jest uzyskiwanie energii z chodzenia, co zostało przeprowadzone za pomocą wkładki do butów z piezoelektryczną warstwą folii PE-PP i przedstawione w artykule. Obliczono maksymalną moc, jaką można otrzymać z energii chodzenia przy zastosowaniu piezoelektrycznego elementu polietylen-polipropylen (PE-PP). Wartość energii elektrycznej jaką uzyskano z jednej 11,5 µm warstwy folii PE-PP dla jednego kroku o czasie trwania 1 s, co odpowiada 1 Hz, wynosi 340 nJ.

8

Physiological and morphological effects of long-term vagal stimulation in diet induced obesity in rats

51%

Gil K. , Bugajski A. , Kurnik M. , Zaraska W. , Thor P.

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2009

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tom 60

|

nr 3

61-66

9

Nowe stateczniki elektroniczne do lamp fluorescencyjnych i ich zastosowania

44%

Gondek J. , Działek K. , Ciastoń M. , Korpak M. , Pawełczyk J. , Zaraska W.

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tom nr 3

2-5

10

Programowany sterownik reklamy świetlnej na świetlówkach

44%

Gondek J. , Działek K. , Ciastoń M. , Korpak M. , Pawełczyk J. , Zaraska W.

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tom nr 3

6-8

11

Effect of long-term vagal stimulation on food intake and body weight during diet induced obesity in rats

44%

Bugajski A. J. , Gil K. , Ziomber A. , Zurowski D. , Zaraska W. , Thor P. J.

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nr 1

5-12

12

Pulsating electromagnetic field stimulation prevents cell death of puromycin treated U937 cell line

37%

Kaszuba-Zwoinska J. , Wojcik K. , Bereta M. , Ziomber A. , Pierzchalski P. , Rokita E. , Marcinkiewicz J. , Zaraska W. , Thor P.

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nr 2

EN

Aim of study was to verify whether pulsating electromagnetic field (PEMF) can affect cancer cells proliferation and death. U937 human lymphoid cell line at densities starting from 1x106 cells/ml to 0.0625x106 cells/ml, were exposed to a pulsating magnetic field 50Hz, 45±5 mT three times for 3 h per each stimulation with 24 h intervals. Proliferation has been studied by counting number of cells stimulated and non-stimulated by PEMF during four days of cultivation. viability of cells was analyzed by APC labeled Annexin V and 7-AAD (7-amino-actinomycin D) dye binding and flow cytometry. Growing densities of cells increase cell death in cultures of U937 cells. PEMF exposition decreased amount of cells only in higher densities. Measurement of Annexin V binding and 7-AAD dye incorporation has shown that density-induced cell death corresponds with decrease of proliferation activity. PEMF potentiated density-induced death both apoptosis and necrosis. The strongest influence of PEMF has been found for 1x106cells/ml and 0.5x106 cells/ml density. To eliminate density effect on cell death, for further studies density 0.25x106 cells/ml was chosen. Puromycin, a telomerase inhibitor, was used as a cell death inducer at concentration 100 µg/ml. Combined interaction of three doses of puromycin and three fold PEMF interaction resulted in a reduced of apoptosis by 24,7% and necrosis by 13%. PEMF protects U937 cells against puromycin- induced cell death. PEMF effects on the human lymphoid cell line depends upon cell density. Increased density induced cells death and on the other hand prevented cells death induced by puromycin.

13

Effects of continuous microchip (MC) vagal neuromodulation on gastrointestinal function in rats

37%

Krolczyk G. , Zurowski D. , Sobocki J. , Slowiaczek M. P. , Laskiewicz J. , Matyja A. , Zaraska K. , Zaraska W. , Thor P. J.

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nr 4,1

EN

Afferent fibers from gastrointestinal tract outnumber efferents ten times in vagal nerves. Modifying the afferent input makes possible to change discharge of vagal efferents affecting gastrointestinal functions in process known as neuromodulation (NM). Lately it has been used in the treatment of pain and hyperactive neurogenic bladder in urology. MC induced NM may therefore provide a concurrent to pharmacology tool, in treatment of gastrointestinal disorders. The aim of this study was to investigate the effects of long term neuromodulation procedure with use of MC on gastric motility, secretion and weight control in conscious rats. Experiments were performed on 30 Wistar male rats (250—350 g) divided in two groups: sham operated and microsurgically implanted with MC on left vagal nerve below diaphragm. Following stimulation parameters were used: frequency of 0.5—30 Hz, amplitude of 0.55 V, impulse duration of 10 ms in monophasic fashion. In both groups food intake and body weight were measured through the period of 2 weeks after recovery period. Then gastric fistula was implanted in gastric antrum and fasted gastric motility recorded with use of PowerLab system (Australia). Gastric emptying and secretion were also tested with use of phenol red and automatic titration methods. On the daily basis glucose level with standard test and leptin after MC implantation were measured. Recording of vagal activity in fasted rats showed burst of action potentials about 5 ± 2,5 in period of 5000 sec, each burst with spike frequency up to 35 Hz. Food (5 ml of Intralipid – intragastrically) almost doubled amount of bursts to 12 ± 5 in period of 5000 sec with increase in frequency at spike up to 50 Hz. MC induced vagal activity showed continuous spike activity similar to fed pattern. MC induced NM decreases daily food intake by 6% (33.6 ± 4.8 vs control 35.5 ± 4.8 g, p < 0.01). Body weight gain in rats before MC implantation decreased by 20% within 2 weeks after recovery (34.8 ± 9.08 vs control 23.56 ± 4.15 g). Fasting control glucose level also decreased of 5.5% (93.15 ± 9.3 vs control 98.5 ± 11.2 mg%, p < 0.05). Frequency of gastric contractions did not change significantly in MC versus control but amplitude of contractions increased of about 66.7% (2.0 ± 0.8 vs 1.17 ± 0.52) at the dominant frequency 0.08 Hz range and about 71.5% (1.17 ± 0.35 vs 0.68 ± 0.47, p < 0.05) at the frequency 0.12 Hz. in FFT analysis PowerLab (chart v = 4.01). BAO decreased by 29.25% without H+ concentration changes (0.2 ± 0.14 vs 0.14 ± 0.12 mmol/30min, p < 0,05) but MAO did not change in MC rats (0.37 ± 0.25 vs 0.42 ± 0.28 mmol/30min, p0.05). Gastric emptying of isotonic solution increased by 10% (90.46 ± 5.34 vs 80.39 ± 9.95) percent of marker passing to duodenum /5min,.p < 0.0001). Our results suggest that MC induced NM affect brain-gut axis via influencing metabolic and gastric function and decreases body weight. 706

14

Loss of interstitial cells of Cajal after pulsating electromagnetic field (PEMF) in gastrointestinal tract of the rats

37%

Kaszuba-Zwoinska J. , Gil K. , Ziomber A. , Zaraska W. , Pawlicki R. , Krolczyk G. , Matyja A. , Thor P. J.

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nr 3

EN

Exposure to the magnetic field has remarkably increased lately due to fast urbanization and widely available magnetic field in diagnosis and treatment. However, biological effects of the magnetic field are not well recognized. The myoelectric activity recorded from the gastrointestinal and urinary systems is generated by specialized electrically active cells called interstitial cells of Cajal (ICCs). Thus it seems rational that ICC have significant vulnerability to physical factors like an electromagnetic field. The aim of this study was to evaluate the influence of pulsating electromagnetic field (PEMF) (frequency 10 kHz, 30ms, 300 µT burst, with frequency 1Hz) on ICCs density in the rat gastrointestinal tract. Rats were divided into two groups (n=32). The first group was exposed to PEMF continuously for 1, 2, 3, and 4 weeks (n = 16), and the second group (n=16) served as a control. Tissue samples of the rat stomach, duodenum and proximal colon were fixed and paraffin embedded. The tangential sections of 5µm thickness were stained immunohistochemically with anti-c-Kit (sc-168) antibody and visualized finally by DAB as chromogen (brown end product). C-Kit positive branched ICC-like cells were detected under the light microscope, distinguished from the c-kit-negative non-branched smooth muscle cells and from the c-kit positive but non-branched mast cells and quantitatively analyzed by MultiScan computer program. Apoptosis detection was performed with rabbit anti-Bax polyclonal antibody (Calbiochem, Germany) and LSABTM 2 visualization system. The surface of c-Kit immunopositive cells decreased after exposure to PEMF in each part of the gastrointestinal tract. Reduced density of ICCs was related to exposure time. The most sensitive to PEMF were ICCs in the fundus of the stomach and in the duodenum, less sensitive were ICCs in the colon and pacemaker areas of the stomach. No marked changes in ICC density in the pyloric part of the stomach were observed. We demonstrate that the PEMF induced apoptosis dependent decrease in ICC expression.

15

Magnetic field anti-inflammatory effects in Crohn's disease depends upon viability and cytokine profile of the immune competent cells

37%

Kaszuba-Zwoinska J. , Ciecko-Michalska I. , Madroszkiewicz D. , Mach T. , Slodowska-Hajduk Z. , Rokita E. , Zaraska W. , Thor P.

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nr 1

EN

AIM. We investigated effects of pulsating electromagnetic field (PEMF-50 Hz, 45 ± 5 mT) on viability and cytokine production by human peripheral blood mononuclear cells (PBMC) from healthy donors and from Crohn’s disease patients (CD). METHODS. The study was performed after activation of cells with phytohaemaglutinin (PHA) and lipopolisaccharide (LPS). Exposure of PBMC cultures to PEMF from both CD patients and from healthy donors decreased cell’s viability of about 10% and 5% (p>0,05) respectively. PEMF influence was most effective after threefold application. Susceptibility of PBMCs to magnetic field exposure differs among the stimulated (PHA, LPS) and not stimulated (NS) cells. Mitogen activated cells during cell division are most susceptible to induction of the cell death as a result of magnetic interaction, contrary PEMF exposure has minimal effect on non-diving PBMCs from CD patients and from controls. Decreased viability of the Crohn derived cells upon magnetic stimulation was accompanied by altered cytokines profile. Exposed and stimulated PBMCs from Crohn patients decreased IFN- proinflammatory and increased IL-10 anti-inflammatory cytokine production. The electromagnetically induced cell death could be an important step for non-invasive PEMF treatment in chronic inflammatory diseases.