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Open access

Wojciech Łabuś, Marek Kawecki and Mariusz Nowak

The Role of Tissue Engineering in the Treatment of Burn Wounds

Open access

Piotr Richter, Jerzy Sałówka and Wojciech Nowak

Neuroanatomy of the Minor Pelvis-Significant Area in the Surgery of Rectal Carcinoma

Open access

Anna Majchrzak and Wojciech Nowak

Abstract

Adsorption is considered as one of the most promising technologies for CCS. Gas adsorption involves the separation of gaseous components from flue gas using solid adsorbents. The gaseous component, adsorbate, is adsorbed from the gas phase on a solid material. Regarding CO2 adsorption, it is important to consider the parameters, that is the high sorption capacity, CO2 selectivity, regeneration and stability in multiple cycles. New directions for the development of adsorbents are focused on increasing their capacity – for this purpose, amine impregnation is carried out. This paper presents a new approach to obtaining mesoporous material from fly ash and, based on this, a new physico-chemical adsorbent obtained by impregnation. The effectiveness of the process was confirmed by thermogravimetric analysis and FTIR infrared spectroscopy.

Open access

Łukasz Dunajski, Wojciech Kruk and Wojciech Nowak

Abstract

According to a fuel flexibility, fluidized bed boilers are considered as appropriate for biomass combustion as cofiring. But the burning of fuels such as forest and agricultural biomass raises a number of operational problems. Most important of these problems are bed agglomeration and deposition. Deposition appears when biomass contains significant amounts of alkali elements, such as sodium and potassium. The purpose of the work is to select a fuel additive to overcome these operational problems. Investigations were conducted in two stages at a pilot scale 0.1 MWth laboratory circulating fluidized bed reactor. As the fuel, the mixture of biomass contained forest residues, sunflower husks, straw and wood pellets from mixed woods was selected. In the first stage biomass was burnt without any additives, while in the second one the fuel was enriched with some additive. The additive (liquid mixture of chemicals) was added to the fuel in amounts of 1 dm3 per 5-10 Mg of fuel. The following operational parameters were examined: temperature profiles along the height of the circulating fluidised bed column, pressure profiles, emissions. After the tests, the laboratory reactor was inspected inside. Its results enables expression of the following conclusions: there was no agglomeration during fuel additive testing, and the deposition was reduced as well. Moreover, the parts (heating surfaces, separator) of the laboratory reactor were coated with a protective layer. The layer covered microcracks and protected the parts from deposition for a long period after the operation.

Open access

Bożena Boryczko, Zygmunt Kolenda and Wojciech Nowak

Abstract

The paper demonstrates that the possibilities of producing reliable long-term energy forecast are limited. Global economic growth is so dynamic that the changes resulting from scientific and technological progress, which we experience, do not allow for the identification of goals over longer time intervals. For this reason, forecasting up to 2035, 2040, 2060 is devoid of its fundamental value, which is the reliability of results obtained. Are predictions to be conservative (this applies to richer countries) or are they to produce a paradigm shift by, for example, strongly imposing the requirement of increasing energy security, which is important for our country? In light of the broadness of the issues, this paper is limited to considerations relating to forecasting the primary energy demand. Detailed examples are presented for the Polish energy system.

Open access

Piotr Wałęga, Michał Romaniszyn and Wojciech Nowak

Abstract

The aim of the study was to present our own experience in the treatment of anal fistulas by means of VAAFT (Video-Assisted Anal Fistula Treatment).

Material and methods. Twenty patients were qualified for the VAAFT procedure. All were subjected to diagnostics. Two patients after the diagnostic stage underwent classical fistula surgery. The remaining 18 patients were subjected to the full procedure (diagnostic fistuloscopy, supply of the internal ostium, and coagulation of the fistula canal). The mean observation period was 10 months.

Results. In most cases the trans-sphincter fistula was observed during the diagnostic phase, including three with additional fluid compartments. There was one intersphincteric fistula. Considering the 18 patients subjected to the full VAAFT procedure the internal ostium was supplied by means of an advancement flap in 3 cases, while in 11 by means of a mattress suture, including one with additional tissue glue. In 4 cases the internal ostium was tightly covered by mucosa. Surgical complications were not observed during the procedure. During further observation a permanent fistula was observed in 4 (22%) patients, and in two (17%), recurrence of anal fistula. In the remaining 12 patients one observed healing without fistula recurrence. Complications were not observed, including stool and gas control deterioration (based on the FISI scoring).

Conclusions. The VAAFT method does not affect sphincter efficiency, no intra- and postoperative complications were observed. As compared to other minimally invasive procedures a comparable recovery rate is observed without the risk of incontinence. It is the only method enabling the intraoperative identification of the internal ostium and fistula canal under visual control. Initial optimistic results require further investigations on a larger group of patients.

Open access

Małgorzata Szyc and Wojciech Nowak

Abstract

This paper is devoted to application of adsorption process for cooling power generation in a cooling devices. Construction and working principle of a water-silica gel adsorption chiller has been presented and the basic refrigeration cycle has been discussed. The article outlines behavior of a single-stage adsorption system influenced by changes in cycle time. The effect of cycle time and inlet chilled water temperatures on the main system performance parameters has been analysed

Open access

Michał Romaniszyn, Piotr Richter, Piotr Walega, Jakub Kenig, Marcin Nowak and Wojciech Nowak

Low-Anterior-Resection Syndrome. How Does Neoadjuvant Radiotherapy and Low Resection of the Rectum Influence the Function of Anal Sphincters in Patients with Rectal Cancer? Preliminary Results of a Functional Assessment Study

The aim of the study was to assess the influence of neoadjuvant radiotherapy and resection of the rectum on the functional parameters of anal sphincters.

Material and methods. 20 patients with rectal cancer, qualified for low anterior rectal resection with neoadjuvant radiotherapy were enrolled in the study group. The study protocol included an anorectal manometry, electromyography and fecal incontinence questionnaire (FISI) before radiotherapy, after radiotherapy, and after the operation.

Results. Of the 20 patients 12 were included in the final analysis, because 8 patients were re-qualified to abdomino-perineal resection of the rectum after neoadjuvant treatment. There were no significant changes in anal pressures assessed 5 to 8 days after radiotherapy. In 3 cases (25%) pathological changes in RAIR reflex were found in the manometric examination. After low anterior resection mean basal anal pressures were significantly lower, whereas squeeze anal pressures did not change significantly. In 7 patients (58%) the RAIR reflex was pathological or even absent after low anterior resection. Changes in manometric parameters correlated with FISI incontinence assessment after the operation. In electromyographic examination action potentials of motoric units of the external anal sphincter were still present both after radiotherapy, and after operation.

Conclusions. Fecal incontinence after low anterior resection of the rectum seems to be caused mostly by changes in autonomic functionality of anal sphincters and lack of compliance of the neorectum, since the influence of neoadjuvant radiotherapy and the operation itself on the somatic innervation of anal sphincters seems to be minimal.

Open access

Dorota Nowak-Woźny, Wojciech Moroń, Bartosz Urbanek and Wiesław Rybak

Abstract

The paper presents the results of the mechanical, electrical, CCSEM and XRD measurements of hard coal, conducted in simulated conditions of sintering in atmospheres of O2/CO2,. The changes of the coal ash resistivity are correlated with the content of the oxides and with the sintering temperature determined by the mechanical test and Leitz method. The SEM-EDS analysis was conducted for deposits on the probe. The changes of the measured ash samples, observed during sintering process in O2/CO2 atmosphere, were discussed in the ash microstructure point of view.

Open access

Iwona Adamiec-Wójcik, Andrzej Nowak and Stanisław Wojciech

Abstract

Dry electrostatic precipitators (ESPs) are widely used for purification of exhaust gases in industrial applications. Maintenance of their high efficiency depends primarily on periodical cleaning of the collecting electrodes (CEs). Dust removal (regeneration of CEs) is realized by inducing periodical vibrations of the electrodes. The paper presents results of vibration modelling of a system of CEs; the results were obtained by means of the finite element method, the hybrid finite element method, the finite strip method and a model formulated using Abaqus. Numerical results are compared with those obtained from experimental measurements. Conclusions concerning numerical effectiveness and exactness of the methods are formulated and reasons for differences are discussed.