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1

Operacje żylaków – czy niosą za sobą ryzyko zakrzepicy żył głębokich? Porównanie laserowej obliteracji żyły odpiszczelowej i klasycznej safenektomii

100%

Krasiński Z. , Aniukiewicz K. , Krasińska A. , Krasińska B. , Dzieciuchowicz Ł.

Pediatria i Medycyna Rodzinna

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2017

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tom 13

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nr 3

317-326

EN

Venous diseases, in particular varicose veins of the lower extremities, are one of the most common chronic diseases and a significant cause of morbidity in Europe and the USA. Varicose veins are considered a risk factor for deep vein thrombosis. Most patients with varicose veins have great saphenous vein ostial insufficiency and reflux of varying degrees. Standard treatment in these cases is high ligation and stripping of the great saphenous vein. This surgery, however, carries a risk of thrombotic complications. Minimally invasive procedures, which include endovenous laser ablation of the great saphenous vein, are the current world trends. This method is a relatively new treatment option for great saphenous vein reflux. The authors present the current state of knowledge on the risk of deep vein thrombosis after different surgical procedures for the treatment of varicose veins in the lower extremity. The literature analysis has led to a hypothesis that lower limb varicose vein surgeries that involve laser obliteration of the great or small saphenous veins carry a lower risk of deep vein thrombosis compared with conventional surgeries. Tumescent anaesthesia, short duration of the procedure and rapid return to physical activity may play a role in deep vein thrombosis prevention. The authors underline that thromboprophylaxis should be implemented irrespective of the method, using risk evaluation, e.g. based on the Caprini scale.

PL

Choroby układu żylnego, a zwłaszcza żylaki kończyn dolnych, są jedną z najczęstszych chorób przewlekłych, a także zasadniczym powodem chorobowości w Europie i USA. Żylaki kończyn dolnych wymieniane są także jako czynnik ryzyka zakrzepicy żył głębokich. Większość chorych z żylakami ma niewydolne ujście żyły odpiszczelowej i różnego stopnia refluks. Standardowym leczeniem w tym wypadku jest wysokie podwiązanie żyły odpiszczelowej i jej stripping. Operacja ta jest obarczona również ryzykiem wystąpienia powikłań zakrzepowych. Obecnie trend światowy stanowią operacje małoinwazyjne, do których należy wewnątrzżylna laserowa ablacja żyły odpiszczelowej. Jest ona stosunkowo nową opcją leczenia refluksu w żyle odpiszczelowej. Autorzy przedstawiają obecny stan wiedzy na temat ryzyka zakrzepicy żył głębokich w odniesieniu do różnych zabiegów operacyjnych żylaków kończyn dolnych. Po analizie piśmiennictwa światowego stawiają tezę, że operacje żylaków kończyn dolnych, w trakcie których wykonuje się obliterację laserową żyły odpiszczelowej lub odstrzałkowej, obarczone są mniejszym ryzykiem zakrzepicy żył głębokich w porównaniu z operacjami klasycznymi. Znaczenie w zapobieganiu zakrzepicy żył głębokich mogą mieć znieczulenie tumescencyjne, krótszy czas zabiegu oraz szybki powrót do normalnej aktywności fizycznej. Autorzy podkreślają jednocześnie, że profilaktykę przeciwzakrzepową należy wdrażać niezależnie od metody, stosując do określenia wskazań ocenę ryzyka wystąpienia tego typu powikłań, np. w oparciu o skalę Capriniego.

2

Recovery of HCl from Chloride Leach Solution of Spent HDS Catalyst by Solvent Extraction

88%

Banda R. , Nguyen T. H. , Lee M. S.

Chemical and Process Engineering

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2013

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tom 34

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nr 1

153-163

EN

In the present work, amine based extractant and its mixture with cationic and solvating extractants were tested for the extraction of HCl from chloride solution containing Al(III). The chloride feed solution resulted from the leaching of spent HDS (hydro-desulfurization) catalysts. For this purpose, amine extractants, such as TOA (trioctyl amine), Alamine 336 (a mixture of tri-octyl/decyl amine), Alamine 308 (tri-isooctyl amine), and TEHA (tri 2-ethylhexyl amine) were used and the extraction and stripping behavior of HCl was compared. The extracted HCl was easily stripped from loaded TEHA phase, when compared with the other tested tertiary amine system. Solvent extraction reaction of HCl by TEHA was determined from the extraction data. Unlike TOA and Alamine 336, adding cationic extractant to TEHA had negligible effect on the extraction and stripping of HCl. In our experimental ranges, no Al was extracted by amines and pure HCl was recovered. MaCabe- Thiele diagrams for the extraction and stripping of HCl by TEHA were constructed.

3

Determination of formation constants of uranyl(VI) complexes with a hydrophilic SO3-Ph-BTP ligand, using liquid-liquid extraction

75%

Steczek L. , Narbutt J. , Charbonnel M.-C. , Moisy P.

Nukleonika

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2015

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tom 60

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nr 4

821-827

EN

Complex formation between uranyl ion, UO22+, and a hydrophilic anionic form of SO3-Ph-BTP4- ligand, L4-, in water was studied by liquid-liquid extraction experiments performed over a range of the ligand and HNO3 concentrations in the aqueous phase, at a constant concentration of nitrate anions at 25°C . The competition for UO22+ ions between the lipophilic TODGA extractant and the hydrophilic L4- ligand leads to the decrease in the uranyl distribution ratios, D, with an increasing L4- concentration. The model of the solvent extraction process used accounts - apart from uranyl complexation by TODGA and SO3-Ph-BTP4- - also for uranyl complexation by nitrates and for the decrease in the concentration of the free L4- ligand in the aqueous phase, due to its protonation, bonding in the uranyl complex and the distribution between the two liquid phases. The unusually strong dependence of the D values on the acidity, found in the experiment, could hardly be explained as due to L4- protonation merely. Three hypotheses were experimentally tested, striving to interpret the data in terms of additional extraction to the organic phase of ion associates of protonated TODGA cation with either partly protonated anionic L4- ligands or anionic UO22+ complexes with NO3 - or L4-. None of them has been confirmed. The analysis of the results, based on the formal correction of free ligand concentrations, points to the formation of 1 : 1 and 1 : 2 uranyl - SO3-Ph-BTP complexes in the aqueous phase. The conditional formation constant of the 1:1 complex has been determined, logßL,1 = 2.95 ± 0.15.

4

Removal of phenols from aqueous solutions with solvating extractants

75%

Regel-Rosocka M. , Wiśniewski M.

Polish Journal of Chemical Technology

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2010

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tom 12

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nr 3

19-23

EN

The removal of selected phenols (phenol, 4-methoxyphenol, 4-fluorophenol, 4-nitrophenol, 4-methylphenol, 4-chlorophenol, 2,4-dichlorophenol) from aqueous streams by liquid-liquid extraction is studied. Butylene and propylene carbonate - are used as green extractants. They permit to remove almost 100% of the examined phenols from feed solutions of phenol concentration about 20 g/dm3. Additionally, stripping of phenols from loaded organic phases is carried out with NaOH. The results of extraction parameters for alkylene carbonates (extraction efficency and distribution ratio) are compared with commercial solvating extractant - Cyanex 923.

5

The effectiveness of hydrated lime as asphalt concrete additive

75%

Jaskuła P.

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2007

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tom No. 10

99-109

EN

This paper evaluates the effectiveness of hydrated lime as an additive to asphalt concrete based on laboratory, as well as field tests carried out on the rest section. The research included testing of the resistance to the action of water and frost and to permanent deformation, as well as establishing of pavement condition survey parameters, including transverse profile and skid resistance on the test section constructed with asphalt mixtures containing hydrated lime or liquid antistripping additive. It was established that hydrated lime may be added to asphalt concrete mixtures as an alternative to chemical antistripping additives.

6

Water and frost resistance of gap - graded asphalt modified with the SBS polymer and hydrated lime

75%

Iwański M. , Pobocha M.

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2008

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tom No. 11

29-36

EN

Gap - graded asphalt (MNU) has high resistance to the traffic, however, due to its specific grading it is more prone to a destructive effect of the climatic factors compared to other bituminous mixes. In order to ensure its durability, the mixture was modified with the use of the SBS polymer and hydrated lime. Asphalt was modified with the addition of 2, 4, 6, 8 % of the SBS polymer, while hydrated lime was dispensed in the filler in the amounts 10, 20, 30, 40 and 50 %. The performed research into the resistance of MNU to high and low temperatures as well as to water and frost showed a positive impact of the two modifiers on the durability and high mechanical properties of MNU.

7

SEM and profilometric evaluation of enamel surface after air rotor stripping – an in vitro study

75%

Mikulewicz M. , Szymkowski J. , Matthews-Brzozowska T.

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2007

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tom Vol. 9, nr 1

11-17

EN

The aim of the study was to evaluate roughness of the enamel surface after Air Rotor Stripping (ARS). Thirty interproximal surfaces of human premolars were used as the biological material. Research was conducted using a contact profilometer and a scanning electron microscope (SEM). Sets of 3D parameters and topographical maps of enamel surface before and after ARS treatment were used to define roughness of the surfaces. SEM images of stripped surfaces were taken with microscopic magnification of 100× and 1000×. The data revealed a general roughness of enamel arising after ARS procedure. Summarized values of chosen parameters increased after ARS procedure compared to the values of untreated enamel. Topographical maps showed areas of both well polished and badly polished enamel. In conclusion, comparison of the mean values of the measured parameters of ARS treated enamel surfaces indicated that roughness of the enamel arises after ARS, but it must be emphasized that on every evaluated surface well polished areas were also present. Moreover, the well polished areas were smoother than those on the untreated enamel surfaces. Contact fluoridation and improved oral hygiene after ARS appear to be necessary because of the presence of areas of increased roughness on evaluated surfaces.