Absolute molecular transition frequencies measured by three cavity-enhanced spectroscopy techniques.

Absolute frequencies of unperturbed (12)C(16)O transitions from the near-infrared (3-0) band were measured with uncertainties five-fold lower than previously available data. The frequency axis of spectra was linked to the primary frequency standard. Three different cavity enhanced absorption and dispersion spectroscopic methods and various approaches to data analysis were used to estimate potential systematic instrumental errors. Except for a well established frequency-stabilized cavity ring-down spectroscopy, we applied the cavity mode-width spectroscopy and the one-dimensional cavity mode-dispersion spectroscopy for measurement of absorption and dispersion spectra, respectively. We demonstrated the highest quality of the dispersion line shape measured in optical spectroscopy so far. We obtained line positions of the Doppler-broadened R24 and R28 transitions with relative uncertainties at the level of 10(-10). The pressure shifting coefficients were measured and the influence of the line asymmetry on unperturbed line positions was analyzed. Our dispersion spectra are the first demonstration of molecular spectroscopy with both axes of the spectra directly linked to the primary frequency standard, which is particularly desirable for the future reference-grade measurements of molecular spectra.

An influence of hypothetical products of dimethylamine ozonation on N-nitrosodimethylamine formation.

The paper concerns formation of N-nitrosodimethylamine (NDMA) upon ozonation of dimethylamine (DMA) aqueous solutions. According to current hypothesis ozonated DMA is oxidized to N-dimethylhydroxylamine (DMHA), then to N-methylhydroxylamine (MHA) and finally to hydroxylamine (HA). HA subsequently reacts with the remain part of DMA to form unsymmetrical dimethylhydrazine (UDMH). Finally UDMH undergoes oxidation with ozone to form NDMA. HA is thought to be an important by-product that increases the NDMA formation. We decided to verify the hypothesis by an ozonation of DMA aqueous solutions in the presence of DMHA, MHA and HA. We have clearly proved that ozonation of DMA in the presence of DMHA and/or MHA does not increase NDMA formation. These results do not exclude the possibility of HA formation during DMA ozonation, but unambiguously show that even if HA is formed during this reaction, it does not have any impact on NDMA formation. In authors opinion the formation of MHA and HA is however doubtful since both compounds seem to be rather products of reduction than oxidation. Therefore HA-DMA reaction cannot be responsible for the formation of NDMA when DMA aqueous solution is ozonized.

[Can HRT be a useful tool in differentiating lamellar macular holes from full-thickness macular holes?]. / Vergleich der SOCT mit Laser-Scanning-Ophthalmoskopie : Differenzierung durchgreifender Makulaforamina von lamellären und Pseudomakulaforamina.

BACKGROUND: The aim of this prospective study was to analyze the specificity and sensitivity of HRT 3 compared with spectral optical coherence tomography (SOCT) in differentiating full-thickness macular holes, lamellar macular holes, and macular pseudoholes. MATERIAL AND METHODS: In 128 patients with a diagnosis made by SOCT of full-thickness macular hole, lamellar macular hole, or macular pseudohole, 161 eyes were examined with the HRT 3 Retina Module, and the results were compared. RESULTS: Using SOCT, full-thickness macular holes were diagnosed in 80 eyes, pseudoholes in 15 eyes, and lamellar macular holes in 66 eyes. Using HRT, full-thickness macular holes were diagnosed in 81 eyes, and pseudoholes and lamellar macular holes (non-full-thickness macular holes) were diagnosed in 80 eyes. In 160/161 cases, the diagnosis with HRT 3 was correct. Compared with SOCT, HRT 3 has a specificity of 98.7% and a sensitivity of 100% in differentiating full-thickness from non-full-thickness macular holes. CONCLUSION: The HRT 3 macular module enables diagnosis of macular holes. Full-thickness macular holes could be differentiated from non-full-thickness macular holes; however, lamellar macular holes could not be differentiated from macular pseudoholes.

The influence of disinfection on aquatic biodegradable organic carbon formation.

The aim of this paper was to assess the extent of biodegradable dissolved organic carbon formation upon disinfection of water with chlorine dioxide. Wide diversity of natural waters has been subjected to reactions with various amounts of ClO(2). For comparison examined waters have also been treated with ozone and chlorine. The application of chlorine dioxide and ozone significantly changed the molecular weight distribution of aquatic organic matter. As a result significant amounts of biodegradable carboxylic acids and aldehydes were generated. The formic, acetic, oxalic and ketomalonic acids as well as formaldehyde, acetaldehyde, glyoxal, methylglyoxal were identified. The productivity of aldehydes calculated for all examined waters and disinfectants amounted 12.7-47.7microgmg(-1) DOC in the case of ozonation, 1.3-8.1microgmg(-1) DOC after chlorination and 1.7-9.4microgmg(-1) DOC for ClO(2) treatment. The highest total concentration of carboxylic acids was determined after the ozonation processes. In this case the organic acids' formation potential was in the range 10.8-62.8microgmg(-1) DOC. Relatively high formation potential (5.3-17.9microgmg(-1) DOC) was determined after the oxidation with ClO(2) as well. In the case of chlorination, the productivity of organic acids was low and did not exceed 3.4microgmg(-1) DOC. The relatively high correlation between BDOC formation and carboxylic acids' formation potential was observed. Thus, carboxylic acids' formation potential may be used as a measure of water potential to form BDOC.

Control of an outbreak due to an adamantane-resistant strain of influenza A (H3N2) in a chronic care facility.

BACKGROUND: Chronic care facility residents are at risk of severe influenza infection and death. Adamantanes have been used by chronic care facilities for influenza A prophylaxis; however, genotypic resistance has altered prophylaxis recommendations. An outbreak of influenza A (H3N2) in a chronic care facility housing neurologically impaired children and young adults and subsequent control measures are described. PATIENTS AND METHODS: Resident charts were retrospectively reviewed. Isolates were characterized by strain identification and pyrosequencing. RESULTS: Although 95 (97%) of 98 residents had been immunized against influenza at the start of the influenza season, 16 (84%) of 19 case patients were identified on the first floor. However, following implementation of enhanced infection control practices and adamantane prophylaxis, only 10 (13%) of 79 case patients were identified on the second floor. Subsequent pyrosequencing studies revealed a serine to asparagine mutation at position 31 of the M2 protein. CONCLUSIONS: Enhanced infection control precautions and adamantane prophylaxis were used to control spread of influenza in a chronic care facility. This outbreak demonstrates the importance of timely and consistent implementation of infection control measures in controlling influenza outbreaks in long term care facilities and raises questions about a possible role for adamantanes in preventing transmission of adamantane-resistant influenza A viruses.

N-nitrosodimethylamine formation during treatment with strong oxidants of dimethylamine containing water.

The aim of the paper is the evaluation of the possibility of NDMA formation, as a result of strong oxidants reacting with DMA. Summarized results of investigations on N-nitrosodimethylamine formation as a result of dimethylamine reactions with chlorine dioxide, ozone and hydrogen peroxide are presented. Preliminary results of experiments on NDMA formation as a result of DMA reactions with permanganate are also shown. The experiments on dimethylamine reactions with chlorine dioxide, hydrogen peroxide and permanganate were carried out at room temperature under static conditions. Ozonation experiments were carried out at room temperature in a semi-continuous mode. Water samples from all experiments described above were collected during the experiment itself and subsequently analyzed with HPLC-IE with UV-Vis detector at 230 nm. NDMA formation was also confirmed by GC-LRMS. NDMA forms as a result of chlorine dioxide, ozone, hydrogen peroxide or permanganate reactions with dimethylamine. both in the presence as well as in the absence of ammonia ions. The presence of nitrites and nitrates in a post-reaction mixture suggests that NDMA are formed as the result of DMA reactions with nitrites. Thus the mechanism of NDMA formation with these oxidants is different than that described by Mitch et al. and Choi et al. The results also showed a conversion ratio of DMA to NDMA of even up to a single percent (with relation to amines), a simultaneous decrease of NDMA formation potential with a decrease of pH, however, in the case of chlorine dioxide application, a maximum conversion ratio was observed, as well the NDMA formation potential is strongly dependent on the oxidant/DMA ratio.

[Diagnosis and evaluation of macular hole with the HRT 2 retina module]. / Diagnose und Evaluierung von Makulaforamina mit dem HRT 2 Retina Modul.

BACKGROUND: This prospective study analyzed the usefulness of the HRT 2 retina module as a diagnostic tool for macular hole diagnosis. The influence of the preoperative status on postoperative anatomic and functional results is also discussed. Preoperative and postoperative retinal tomography maps (HRT 2) were compared with optical coherent tomography (OCT III) and spectral optical coherent tomography (SOCT). METHODS: Fifty eyes of 46 consecutive patients with stage III/IV macular hole underwent vitrectomy with internal limiting membrane peeling and fluid/air exchange. HRT 2, OCT III, and, in eight cases, SOCT images were analyzed. RESULTS: The mean best corrected visual acuity 1 week before surgery was 0.086+/-0.074 (0.01-0.35). The final best corrected visual acuity 12 months after surgery was 0.32+/-0.24 (0.01-1.0). Anatomic success was noted in 46/50 eyes 1 month after the first surgery and in all eyes after the second intervention. In 33/50 eyes (66%), visual acuity improved over two lines. In 13 eyes visual acuity remained stable, and in four eyes worse visual acuity was noted postoperatively. The mean macular hole diameter in HRT 2 was 497.2 microm and in OCT III was 490 microm. Different values were observed in cases of oval macular holes. The mean macular hole area was 0.193 mm(2). The macular hole radius in HRT 2 can be compared with the minimal diameter in OCT III. It influences the final visual acuity 12 months after surgery. CONCLUSIONS: The HRT 2 macular module enables diagnosis of macular hole and evaluation of its postoperative status. This technique has some advantages because it enables measurement of the macular hole's radius, area, and depth. In cases when the macular hole's radius as measured in HRT and OCT III differs, HRT seems to give more exact data because it shows the entire surface rather than just a cross-section of the retina. Macular hole radius and area as measured with HRT 2 can influence postoperative functional results.

The protection of parsley seedlings (Petroselinum sativum Hoffm. ssp. microcarpum) against damping-off.

The experiment was carried out in the years 2003 and 2004 on parsley cultivar: 'Berlinska', 'Cukrowa', 'Vistula' and 'Kinga'. Mycological analysis of parsley seeds showed, that the most common inhabitans were fungi from genus Alternaria (mainly A. alternata and A. radicina) and Fusarium, especially F. avenaceum and F. oxysporum. The two-year study on the effectiveness of 5 substances--biopreparate Biochikol 020 PC (polymer of chitosol) and Biosept 33 SL (extract of grape-fruit); and fungicides: Amistar 250 SC (BAS azoxystrobin), Dithane M-45 80WP (mancozeb) and Zaprawa Funaben T (carbendazim+thiram) used against parsley damping-off was conducted in glasshouse and field conditions. Seeds of parsley were treated one of tested substances before sowing. The results of glasshouse experiments showed, that the best efficacy exibited Amistar and Zaprawa Funaben T for seedlings cultivar 'Berlinska' and 'Cukrowa' and Biochikol for 'Kinga'. During field experiments Zaprawa Funaben T showed the best efficacy for seedlings 'Berlinska' and 'Vistula'. Preparate Amistar was the best seed dressing for parsley cultivar 'Cukrowa' and 'Kinga'. During glasshouse experiments in control the highest number of decaying seedlings had cultivar 'Berlinska', in field experiments 'Kinga'.

[Vitreous surgery with trypan blue staining of membranes in PVR retinal detachment surgery]. / Glaskörperchirurgie mit Trypanblau bei der Behandlung von PVR-Netzhautablösungen.

BACKGROUND: In our clinic we used trypan blue staining routinely for removal of internal limiting membranes (ILM) and epiretinal membranes (ERM) during vitreoretinal surgery for PVR retinal detachment. PATIENTS AND METHODS: We treated 27 eyes of 27 patients with severe PVR retinal detachment with vitreoretinal surgery. After complete vitrectomy and removal of epiretinal membranes we injected 0.15 % trypan blue solution and proceeded with further removal of the visualized remaining epiretinal membranes and ILM. We performed relaxing retinotomies in 14 eyes. Follow-up lasted six months. RESULTS: After the first surgery the retina was reattached in 24 of 27 eyes and after the second surgery in all eyes. The final visual acuity was: hand movements in 3 eyes, 1/50 or better in 24 eyes (eight of them had a visual acuity of 0.1 - 0.5). No case of macular pucker was observed during the follow-up. CONCLUSIONS: Trypan blue staining during vitreoretinal surgery in PVR retinal detachment therapy allows complete removal of ILM, ERM, and peripheral vitreous. It upgrades the quality of the surgery.

The biological evaluation of Zato 50 WG in protection of carrot against Alternaria blight.

Effectiveness of new fungicide Zato 50 WG (biologically active substances BAS - trifloxystrobin 50%) in the control of Alternaria blight on carrot was studied. Field experiments were carried out in the years 2003-2004 on carrot cv. Koral. As the standard fungicide Amistar 250 SC (BAS - azoxystrobin 250 g/dm3) was used. The results of health status of carrot leaves analysis in first and second year of experiment showed, that development of disease symptoms was lower on leaves of chemical protected plants than on leaves of control plants. The last estimation of infestation degree of carrot leaves made immediately before harvest showed, that standard fungicide Amistar had longer systemic influence on plants. This was confirmed the lower (statistically significant) infestation index of protected carrot in combination with Amistar. The estimations of health status of carrot roots were made directly after digging up indicate, that there wasn't difference of value of infestation index between protected combination and control. Experiment showed, significant effect of tested fungicides on crop quantity of carrot roots per 1 m2. Especially in the second year of study the crop of carrot roots in combination with Zato was higher - statistically significant - than in the rest combinations.

Part II. Chromatography using ultra-stable metal oxide-based stationary phases for HPLC.

In this part of the review authors discuss methods used for modification of metal oxide surfaces. On the basis of literature data it is shown, that silanization of the surfaces do not form stable supports for chromatography. On the other hand, the success of polymer modified surfaces such as polybutadiene (PBD) and polystyrene (PS) is emphasized. Permanent modification of metal oxide surfaces with Lewis bases is also widely discussed. Chromatographic properties of polymer modified surfaces of zirconia are discussed in details. The perspectives of carbon-coated metal oxide surfaces in HPLC and high temperature separations are described.

Part I. Chromatography using ultra-stable metal oxide-based stationary phases for HPLC.

The first part of the review contrasts the main drawbacks of silica-based packings such as their relative thermal and chemical instability with excellent stability of metal oxides. The paper concerns mainly ZrO2, TiO2 and Al2O3. Methods of preparation of spherical particles for HPLC are described. Surface chemistry of the oxides is, however, very different from that of silica. Ability of the oxides to ion- and ligand exchange is discussed from a chromatographic point of view.

Biodegradability of organic by-products after natural organic matter oxidation with ClO2--case study.

Apart from well-known chlorites and chlorates, chlorine dioxide also generates easily biodegradable carbonyl compounds and short chain carboxylic acids during water disinfection. The main goal of the presented study was to examine the influence of natural organic matter (NOM) oxidation with chlorine dioxide, on the quantity as well as the quality of formed biodegradable by-products. In the experiments conducted at the pilot plant the sand filtered water (MWI) and ozonated/biofiltrated water (BAF) were oxidised with ClO2. The amount of BDOC formed as a result of the oxidation of both waters with ClO2 was compared. The results showed considerable differences in formation of ClO2 oxidation by-products between non-ozonated and ozonated/biofiltered waters. The disinfection of ozonated/biofiltrated water with ClO2 generated comparable amounts of aldehydes and much higher amounts of carboxylic acids than ClO2 oxidation of sand filtered water. These findings are essential for waterworks with ozonation/biofiltration units and ClO2 disinfection implemented.

Reactivity of natural organic matter fractions with chlorine dioxide and ozone.

The effects of ozone and chlorine dioxide on the aquatic natural organic matter (NOM) were studied. The natural as well as oxidised organic matter in aerated and sand filtered water were fractionated using XAD, anion-exchange, and cation-exchange resins procedure into humic acid, hydrophobic acids and neutrals, and hydrophilic acids, bases and neutrals. The main NOM components were hydrophobic, while oxidation with both ozone and chlorine dioxide increased the proportion of hydrophilic fractions. High-pressure size exclusion chromatography with UV-254 nm and UV-220 nm detection was used to determine the differences between molecular weight distribution of natural and oxidised organic matter fractions. The main purpose of this paper was to compare the reactivity of individual NOM fractions with oxidants in order to compare the productivity of biodegradable by-products after oxidation with chlorine dioxide and ozone. The quantity as well as the quality of by-products were analysed by means of ion and gas chromatography.

Effectiveness of some means using against root rot on parsley seedling root.

The results of a two-year study concern the effectiveness of 4 substances--biopreparate Chitosol (beta-1,4 D-glucosamine polymer) and fungicides: Rovral Flo 255 SC (BAS iprodione 255 g/dm3), Sportak Alpha 380 EC (BAS prochloraz 0,300 dm3/dm3 and carbendazim 80 g/dm3) and Zaprawa Funaben T (carbendazim 20% + tiuram 45%)--used against root rot and plant rot was described. These experiments were conducted in glasshouse and field conditions. Root of parsley cultivar Berlinska were treated one of tested substances autumn before storage period in clamp or spring immediately before planting seedling roots. The results showed that autumn dressing was ineffective, indices of root infestation were similar in each combination including control in both years of observation. Spring dressing was better, but not only in controls were many parsley plants decaying in the fields. Among substances used for spring dressing of seedling roots, the best efficacy exhibited Zaprawa Funaben T and Sportak Alpha 380 EC.

Reduction of ClO2 demand by ClO2 oxidation and subsequent GAC filtration.

The effective removal of soluble natural organic matter (NOM) during water treatment can significantly decrease the ClO(2) demand of processed water. This can be achieved through the oxidation and/or the removal of NOM. The purpose of the study was to examine the influence of ClO(2) oxidation and subsequent GAC filtration on the final ClO(2) demand of treated water. The study showed the ClO(2) demand to be strongly correlated with the abundance of high molecular fractions of NOM in treated water. As it was shown, this part of NOM was effectively removed during the GAC filtration. Moreover, the pre-treatment of water with ClO(2) considerably increased the total capacity of GAC filters for organic and inorganic (i.e. chlorites) oxidation by-products. Therefore, the oxidation of NOM molecules in conjunction with a very efficient GAC filtration can be successfully employed to control the abundance of high molecular NOM components, and thus the ClO(2) demand of finished water.

The role of transarterial embolization in the treatment of renal cell carcinoma.

OBJECTIVE: To review the role of transarterial renal embolization in our unit, assessing the indications, tolerability and efficacy of this technique for treating renal cell carcinoma (RCC). PATIENTS AND METHODS: Thirty patients undergoing transarterial embolization between 1991 and 1999 were identified and 25 case notes analysed retrospectively. RESULTS: Most patients (14 of 25) presented with less advanced (stage I-III) RCC who were unable or unwilling to undergo radical surgery; the remainder (11) presented with advanced (stage IV) disease. The embolizing agent was ethanol, usually combined with stainless steel coils (85% of cases). Procedural pain and fever was controlled successfully. The median hospital stay associated with the procedure was 4 days. At the time of analysis six of 11 stage IV and 11 of 14 stage I-III patients were alive (median follow-up 27 and 39 months, respectively). Symptoms from the primary tumour were well controlled. Overall, 17 of 25 (68%) of patients reported no problems while three (12%) required brief hospital admission for treatment of persistent haematuria. Fourteen patients were subsequently re-staged; the primary tumour in two had increased, in seven remained unchanged and in five it decreased. No patients without metastases developed them and metastases in two patients regressed. CONCLUSION: Transarterial embolization is associated with minimal morbidity and complications, and subsequent symptom control is good. The effect of palliative embolization on RCC progression is unknown and requires prospective investigation. Presently, there is no role for cytoreductive embolization; it should be included as a treatment option in clinical trials evaluating such options in patients with metastatic RCC.

Formation of aldehydes upon ClO2 disinfection.

Carbonyl compounds are considered to be the most common ozonation by-products. Apart from well-known chlorites and chlorates, chlorine dioxide (ClO(2)) also generates organic by-products. The goal of this paper is an investigation into the influence of disinfection with ClO(2) on the aldehydes formation. Three types of waters were disinfected with different doses of ClO(2) at the various pH values. The results of size exclusion chromatography show that the reaction of ClO(2) with humic fraction of natural organic matter proceeds mainly on an aromatic part of the molecules. The results obtained indicate that the level of carbonyls concentration can significantly increase with the time of ClO(2) reaction with carbonyl precursors in treated water. There is no noticeable correlation between quantity of aldehydes and pH value of disinfected water. The range of "productivity" of aldehydes in water treated with chlorine dioxide is similar to the range estimated for the carbonyls formed upon ozonation.

Aldehyde contamination of mineral water stored in PET bottles.

Aldehyde contaminations that might accompany production of mineral water stored in PET bottles were investigated. One of the production lines of carbonated mineral water in Poland was monitored and PET bottles commonly used for mineral water storage were evaluated. Formaldehyde and acetaldehyde were the most important carbonyls identified in series of bottled water samples, but also propanal, nonanal and glyoxal were found in water samples from the production line. Aldehydes are present everywhere in the environment and can be determined even in pure water at low microg l(-1) levels. It was observed that the concentration of acetaldehyde in water stored in PET bottles depended mainly on the concentration of acetaldehyde in PET material and could reach more than 200 microg l(-1). The temperature, time of storage and concentration of carbon dioxide gas contribute to the migration of aldehydes from bottle walls to mineral water. Higher pressure of the carbonated waters and not CO(2) itself or lower pH of waters seems responsible for higher concentration of acetaldehyde.