Bottle Type Research Articles

Multielectron spectroscopy: Auger decays of the argon 2p hole

All the different Auger decay paths of Argon 2p holes have been characterized using a time of flight spectrometer of the magnetic bottle type. All electrons (the photoelectron and up to three Auger electrons) are detected in coincidence and resolved in energy. Double Auger decay is shown to proceed either through a direct process or by intense cascade paths, implying highly excited autoionizing Ar 2+ states, which are identified as Ar 2+ 3s −2 correlation satellites. Triple Auger decay is also observed and estimated to account for 0.2% only of all Auger decay.

Optimising Detection of Microbes in Cord Blood for Banking.

The current FACT/NetCord cord blood (CB) standards require testing of the final CB product for the presence of anaerobic and aerobic bacterial and fungal contamination. Previously, we have reported a reduced rate of microbial contamination when testing the final concentrated product with a single pediatric (0.8%) compared to the plasma waste fraction with both aerobic and anaerobic (5.1%) blood culture bottles (Cytotherapy 7:Suppl 1, Abstr 88, 2005). The issue of sensitivity of bottle type and small volume available from the final product were highlighted. Subsequently, a combination of both protocols was introduced as the routine screening procedure.Aim: To analyse microbial contamination of CB donations using three blood culture bottles and two differing test sample specimens as the screening procedure.Method: Between Jan 2005 and Jul 2006, 1,715 processed CB units were tested for the presence of microbial contamination:after separation from the white cell rich product, 10 mL of resulting plasma waste fraction was aseptically inoculated into each of an adult anaerobic (An) and adult aerobic (Ae) FAN BacT/Alert blood culture bottle (bioMerieux) andafter completion of processing and prior to freezing, 1 mL sample of the final product was inoculated into a paediatric (Pd) FAN BacT/Alert blood culture bottle (bioMerieux).The bottles were incubated as per the manufacturer's instructions for a maximum of five days. Bottles indicating positive growth were subcultured and species identification performed.Results: A total of 46 CB units tested positive for bacterial growth, giving a microbial contamination rate of 2.68%. No fungal contamination was reported. Of these, 23 (50%) tested positive only in the plasma waste fraction, 18 (39%) tested positive only in the final product, and only 6.5% of CB units were positive in all three bottles. Of the 23 CB units positive from the plasma fraction, 20 had growth only in the anaerobic bottle and 2 had growth only in the aerobic bottle. Microbes were detected in the plasma fraction and not in the final product, and vice versa, and microbes detected in the plasma fraction were generally different to those detected in the final product. The plasma fraction detected mainly anaerobic organisms, the most common of which was Bacteroides (n=11). The Pd bottle grew aerobic and facultative anaerobes and missed the majority of the obligate anaerobes detected in the plasma fraction by either the Ae or An bottles. The most common organism detected in the Pd bottle was staphylococcus sp (n=8), of which only two were detected in the plasma waste fraction using either the anaerobic or aerobic bottles. [Display omitted] Conclusions: This data indicates that to optimise microbial detection in CB units, test protocols should include screening of both the plasma waste fraction and final product; and further, protocols should include testing with systems that promote growth of both anaerobic and aerobic organisms. It is not clear from this study whether microbe-positive CBs were not detected in the two test sources of sample (plasma vs final product) due toinability of some organisms to grow in specific bottles and /orlow sample volume issues orwhether microbes were sequestered during processing into one specific fraction.

Recovery of Fingerprints from Fire Scenes and Associated Evidence

A lack of information concerning the potential recovery of fingerprints from fire scenes and related evidence prompted several research projects. Latent prints from good secretors and visible prints (in blood) were placed on a variety of different surfaces and subsequently subjected to "real life" fires in fully furnished compartments used for fire investigation training purposes. The items were placed in various locations and at different heights within the compartments. After some initial success, further tests were undertaken using both latent and dirt/grease marks on different objects within the same types of fire compartments. Subsequent sets of tests involved the recovery of latent and visual fingerprints (in blood, dirt and grease) from different types of weapons, lighters, plastic bags, match boxes, tapers, plastic bottles and petrol bombs that had been subjected to the same fire conditions as previously. Throughout the entire series of projects one of the prime considerations was how the resultant findings could be put into practice by fire scene examiners in an attempt to assist the police in their investigations. This research demonstrates that almost one in five items recovered from fire scenes yielded fingerprint ridge detail following normal development treatments.

Effects of Delayed-Entry Conditions on the Recovery and Detection of Microorganisms from BacT/ALERT and BACTEC Blood Culture Bottles

Manufacturers generally recommend that blood culture bottles be loaded into instruments within a short time of collection. However, in our experience, delays often occur prior to loading the bottles. We examined the effect of holding bottles under various temperatures (T)-room temperature (RT), 4 degrees C, 37 degrees C, and RT for 2 h following incubation at 37 degrees C (to simulate transit [TR])-and for various holding times of 4, 12, and 24 h. We utilized the BacT/ALERT system with FA and FN bottles and the BACTEC system with Plus (PL) and Lytic 10 (LY) bottles. Standardized inocula and 5 ml of blood were added to each bottle. Fifteen organisms were evaluated based upon expected performance: aerobic (FA and PL), anaerobic (FN and LY 10), and facultative (all bottles). Based upon expected performance, the FA and FN bottles recovered 458 of 468 organisms and 282 of 288 organisms, respectively, whereas the PL and LY bottles recovered 453 of 468 organisms and 257 of 288 organisms, respectively (P = <0.001, FN versus LY). There were 3, 11, 21, and 27 false-negative results for bottles held at 4 degrees C, RT, 37 degrees C, and TR, respectively. There were 4, 8, and 50 false-negative results for bottles held for 4, 12, and 24 h, respectively. Our results support holding these four bottle types at 4 degrees C or at RT for up to 24 h and at 37 degrees C for up to 12 h. We propose that manufacturers only need to make claims for "delayed entry" when these bottles are held for more than 24 h at 4 degrees C or at RT or for more than 12 h at 37 degrees C.

Persistence of 17 -Estradiol in Water and Sediment-Pore Water from Cave Streams in Central Missouri

Concentrations less than 10 ng/L of 17 β-estradiol (E2), a natural estrogen, have been linked to adverse health effects in fish, including skewed sex distributions, reproductive failure, and organ impairment. The persistence of E2 in carbonate aquifer systems is not well documented. Water and sediment from cave streams within the Ozark Plateau of Missouri, USA, were collected and analyzed for E2. The persistence of E2 in the water was examined in two separate experiments, in which the holding temperatures (20°C vs. 4°C), bottle type, exposure to light, and filtration were varied. During two trials, no statistical difference was observed in the concentration of E2, suggesting that E2 is stable within the water. The fate of E2 was also examined in sediment-pore water collected from the cave streams in two independent trials. In trial 1, a significant decrease in E2 was noted over the 29 days of the experiment. However, in trial 2, no change in E2 concentration was observed. The results indicate that E2 is relatively stable in cave stream water and may persist in the sediment.

Identification of chemicals, possibly originating from misuse of refillable PET bottles, responsible for consumer complaints about off-odours in water and soft drinks

Mineral water and soft drinks with a perceptible off-odour were analysed to identify contaminants originating from previous misuse of the refillable polyethylene terephthalate (PET) bottle. Consumers detected the off-odour after opening the bottle and duly returned it with the remaining content to the producers. The contaminants in question had thus been undetected by the in-line detection devices (so-called ‘sniffers’) that are supposed to reject misused bottles. GC-MS analysis was carried out on the headspace of 31 returned products and their corresponding reference products, and chromatograms were compared to find the possible off-odour compounds. Substances believed to be responsible for the organoleptic change were 2-methoxynaphthalene (10 bottles), dimethyl disulfide (4), anethole (3), petroleum products (4), ethanol with isoamyl alcohol (1) and a series of ethers (1). The mouldy/musty odour (5 bottles) was caused by trichloroanisole in one instance. In some cases, the origins of the off-odours are believed to be previous consumer misuse of food products (liquorice-flavoured alcohol, home-made alcohol containing fusel oil) or non-food products (cleaning products, petroleum products, oral moist snuff and others). The results also apply to 1.5-litre recyclable PET bottles, since the nature and extent of consumer misuse can be expected to be similar for the two bottle types.

Protective Influence of Several Packaging Materials on Light Oxidation of Milk

Light-induced degradation reactions in milk create a serious problem for the dairy industry because of the development of off-flavors, the decrease in nutritional quality, and the severity and speed by which these phenomena develop. Packaging materials are essential to avoid this particular deterioration of milk. Therefore, efforts are being made to design protective polyethylene terephthalate (PET) packages. In the present study, a number of PET bottles were compared for their ability to avoid photo-oxidation in UHT semi-skimmed milk. The milk was packed in 3 types of PET bottles: one transparent bottle provided with an active oxygen-binding inner layer, one bottle with perfect light barrier, and one transparent bottle provided with a UV-absorbing additive. During 2 storage experiments, running parallel to each other for 2 mo, chemical milk quality parameters such as fat oxidation, vitamin and protein degradation, oxygen consumption, and color change were monitored. A trained taste panel compared the sensory quality of the illuminated milk stored in these bottles, with milk perfectly protected against light and oxygen. In the first study, milk was continuously illuminated at room temperature. A comparison was made for milk under storage conditions that simulated those expected during display in retail and supermarkets. The results of the 2 shelf-life studies showed that an adequate light barrier was apparently sufficient to avoid the light-induced oxidation of milk during extended storage. Oxygen barriers, on the other hand, did not provide a significant protection, nor did bottles with UV filter. If wavelengths detrimental to riboflavin were not completely excluded by the packaging material, incoming light could still give rise to photo degradation of milk. Accordingly, riboflavin and vitamin A were gradually degraded, milk fat was photo-oxidized, oxygen dissolved in the milk was consumed, and the sensorial quality decreased significantly.

Influence of PET and PET/PEN Blend Packaging on Ascorbic Acid and Color in Juices Exposed to Fluorescent and UV Light

ABSTRACT: Apple and orange juices packed in polyester bottles were stored in dark, intense fluorescent (1500 lux), and UV light conditions in temperature-controlled (22 °C) chambers and monitored more than 7 mo for ascorbic acid content and color changes. Polyester beverage bottles were made of polyethylene terephthalate (PET), or PET blended with 0.25%, 1%, and 4% polyethylene naphthalate (PEN). The cut-off wavelength ranged from 322 nm for PET to 373 nm for the 4% PEN/PET blend. Spectral irradiance, visible light intensity, and light distribution were evaluated in the light chambers and compared with supermarket display lighting and outdoor daylight conditions. Only the UV chamber and sunlight showed significant irradiance at wavelengths below 400 nm. Ascorbic acid (AA) degradation and concurrent color changes occurred in both juices during storage in all 3 lighting conditions and in all 4 bottle types. Zero-order reaction kinetics described the AA degradation rate for all treatments. Apple juice stored in UV had a significantly higher (P < 0.05) AA degradation rate than juice stored in the dark or in fluorescent light. Under UV conditions, apple juice in PET/ PEN bottles had a lower AA degradation rate than the juice in PET bottles. AA degradation in orange juice was less affected by UV exposure than in apple juice. Both juices darkened over time when stored in dark and fluorescent conditions, whereas UV exposure caused some initial bleaching of color before darkening. The bleaching effect was reduced in apple juice stored in the PET/PEN bottles.

Pilot study of water disinfection using solar concentrators in rural communities

The efficiency of solar disinfection for the inactivation of Total Coliforms (TC) and Escherichia coli (EC) in drinking water was tested in two pilot studies performed in rural communities of the States of Chihuahua and Oaxaca, Mexico. The solar disinfection of drinking water (or photodisinfection) is an inexpensive alternative for easy application in rural communities. The study zones were selected mainly because they lack formal water supply systems and the population is forced to consume untreated water directly from rivers and shallow or artesian wells. The efficiency of the water disinfection process based on solar energy was determined in the dry and rainy seasons with water from the most contaminated sources in the study zones. The performed tests consisted of studying the effect of disinfecting water by direct exposure to sunlight during the whole day, with and without solar concentrators, in plastic bottles of commercial beverages. The three types of bottles used were transparent, partially painted black (one half of the bottle, along the longitudinal axis), and totally black. The study shows that, in these geographic zones, the available water must be disinfected before consumption, and disinfection efficiency can reach 100% through the use of solar radiation.

Do child-resistant caps prevent school age children access to prescription medications?

Study objectives: We determine the ability of first- and second-grade children to open prescription medication bottles. Methods: Samples of child-resistant prescription medication bottles were obtained from 3 national vendors (CVS, Walgreen's, Wal-Mart). A convenience sample of first- and second-grade children at a local elementary school were the test subjects. After approval by school administration, parental consent forms were obtained for each participant. On separate occasions, participants present were given 1 style of bottle and asked to open it. Five minutes were allowed, and times were recorded for each child and each type of bottle. Grade level and sex were also noted for each subject. Children were not allowed to discuss opening techniques with other subjects. Results: Three brands of caps were tested. Two were push-down-and-turn style (CVS and Wal-Mart), and 1 (Walgreen's) had a tab that needs to be depressed to open the bottle. For Walgreen's bottles (push tab), 21 subjects attempted to open them. Twenty (95%) of the 21 were successful in an average of 1.8 minutes (range 0.5 to 5 minutes for successful opening). For Wal-Mart (push and turn) bottles, 20 subjects attempted to open them. Twelve (60%) of the 20 were successful in an average of 1.8 minutes (range 0.25 to 4.5 minutes for successful opening). For CVS (push and turn) bottles, 25 subjects attempted to open them. Fourteen (56%) of the 25 were successful in an average of 4.3 minutes (range 0.5 to 4.5 minutes for successful opening). Thirty-five first-grade children attempted to open bottles. Twenty-three (66%) of the 35 were successful in an average of 2.4 minutes (range 0.5 to 4.5 minutes for successful opening). Thirty-nine second-grade children attempted to open bottles. Thirty-two (82%) of 39 were successful in an average of 1.2 minutes (range 0.25 to 4 minutes for successful opening). Twenty-nine boys attempted to open bottles. Twenty-two (76%) of 29 children were successful in an average of 1.6 minutes (range 0.25 to 4 minutes for successful opening). Thirty-two girls attempted to open bottles. Twenty-two (68%) of 32 children were successful in an average of 2.2 minutes (range 0.25 to 5 minutes for successful opening). Conclusion: In a convenience sample of first- and second-grade children, most were able to remove a child-resistant cap in less than 5 minutes. Although children in this age group have some understanding of consequences of taking medications, these data reveal that reliance on resistant caps is not safe. Second-grade children were more adept at opening bottles, although first-grade children had a high success rate. It seems that the medication bottles with child-resistant closures may not provide the degree of safety assumed by many parents. Further testing with preschool children and a senior population is planned.

Preservation and storage techniques for low-level aqueous mercury speciation

Although researchers today generally employ appropriate techniques for the storage and preservation of aqueous samples for ambient-level mercury (ppb) speciation, these methods continue to be poorly documented. Numerous experiments were thus conducted to investigate the effects of acidification and bottle type on holding time for various mercury species [elemental mercury (Hg 0), ionic mercury (Hg(II)), dimethyl mercury (DMHg), monomethyl mercury (MMHg), and dissolved-to-particulate ratio] as well as total mercury (THg). We documented that THg is stable for at least 300 days when stored at 0.4–0.5% acidity in either Teflon or glass bottles. In cases where THg is adsorbed to bottle walls, the addition of BrCl at least 24 h before analysis allowed all Hg to be quantitatively recovered. Polyethylene bottles allowed diffusion of Hg 0 through the bottle walls to or from the sample, depending on the Hg concentration of the sample and storage atmosphere. MMHg in freshwater samples can be stored refrigerated and unacidified for days to weeks with no observed degradation of MMHg. For long-term storage (at least 250 days), samples should be acidified with 0.4% HCl (v/v) and kept in the dark to avoid photodegradation (approximate t 1/2=6 months). For saltwater samples, preservation with 0.2% (v/v) H 2SO 4 is preferred to avoid exceeding the optimal chloride concentration if the distillation procedure is used for MMHg determination. For volatile species (Hg 0 and DMHg), samples should be collected in completely full glass bottles with Teflon-lined caps, as these species are lost rapidly ( t 1/2=10–20 h) from Teflon and polyethylene bottles. Because acids can enhance the rapid oxidation of volatile species, these samples should be stored refrigerated and unacidified and processed within 1–2 days if they cannot be purged and trapped in the field. Hg(II) and the dissolved-to-particulate ratio are more stable and can be stored for a period of days to weeks without preservation.

Efficiency in the disinfection of water for human consumption in rural communities using solar radiation

The efficiency of solar disinfection for the inactivation of Total Coliforms (TC) and Escherichia coli (EC) in drinking water was tested in rural communities of the Guachochi Municipality, in the Tarahumara Sierra, State of Chihuahua, Mexico. The study zone was selected mostly because it lacks formal water supply systems and the population is forced to consume untreated water directly from rivers and shallow or artesian wells without treatment. To determine the bacteriological quality of the water consumed by the population, the amount of TC and EC in the water supplies of 23 communities in the studied municipality was determined. The efficiency of the solar energy based water disinfection process was determined for several months of the humid and dry seasons with water from the most contaminated sources of the study zone. The performed tests consisted in studying the effect of disinfecting water by direct exposure to sunlight during the whole day, with and without solar concentrators, in plastic bottles of commercial beverages. The three types of bottles used were transparent, partially painted black (one half of the bottle, along the longitudinal axis), and totally black. The study shows that, in this geographic zone, the available water must be disinfected before consumption and disinfection efficiency can reach 100% through the use of solar radiation. It was found that, since more than 6 h of daily solar radiation are available during most of the year in this zone, no solar concentrators are really necessary to ensure the complete elimination of bacteria. A complete disinfection takes place by simply placing water bottles in the sunlight during the whole day. Nevertheless, the use of solar concentrators and bottles partially painted black increases the TC and EC inactivation efficiency, reducing the solar exposure time required for a total disinfection to just 2 h. With the use of solar concentrators and partially blackened bottles, the water temperature reached 65 °C, while only 50 °C were achieved when using the same concentrators and completely transparent bottles.

Feeding interventions for growth and development in infants with cleft lip, cleft palate or cleft lip and palate.

Cleft lip and cleft palate are common birth defects, affecting about one baby of every 700 born. Feeding these babies is an immediate concern and there is evidence of delay in growth of children with a cleft as compared to those without clefting. In an effort to combat reduced weight for height, a variety of advice and devices are recommended to aid feeding of babies with clefts. This review aims to assess the effects of these feeding interventions in babies with cleft lip and/or palate on growth, development and parental satisfaction. We searched the Cochrane Oral Health Group's Trials register (June 2001), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2, 2004), MEDLINE (1966 to May 24th 2004), EMBASE (1980 to August 7th 2002), CINAHL (1982 to August 7th 2002), PsychINFO (1967 to August 13th 2002), AMED (1985 to August 13th 2002). Attempts were made to identify both unpublished and ongoing studies. There was no restriction with regard to language of publication. Studies were included if they were randomised controlled trials (RCTs) of feeding interventions for babies born with cleft lip, cleft palate or cleft lip and palate up to the age of 6 months (from term). Studies were assessed for relevance independently and in duplicate. All studies meeting the inclusion criteria were data extracted and assessed for validity independently by each member of the review team. Authors were contacted for clarification or missing information whenever possible. Four RCTs with a total of 232 babies, were included in the review. Comparisons made within the RCTs were squeezable versus rigid feeding bottles (two studies), breastfeeding versus spoon-feeding (one study) and maxillary plate versus no plate (one study). No statistically significant differences were shown for any of the primary outcomes when comparing bottle types, although squeezable bottles were less likely to require modification. No statistically significant difference was shown for infants fitted with a maxillary plate compared to no plate. A statistically significant difference in weight (kg) at 6 weeks post-surgery was shown in favour of breastfeeding when compared to spoon-feeding (mean difference 0.47; 95% CI: 0.20, 0.74). Squeezable bottles appear easier to use than rigid feeding bottles for babies born with clefts of the lip and/or palate, however, there is no evidence of a difference in growth outcomes between the bottle types. There is weak evidence that babies should be breastfed rather than spoon-fed following surgery for cleft lip. No evidence was found to assess the use of any types of maternal advice and/or support for these babies.

Changes in the polyphenolic and volatile contents of "fino" sherry wine exposed to ultraviolet and visible radiation during storage.

Experiments of accelerated oxidation of "fino" sherry wines have been conducted at 25 degrees C and under the influence of UV-visible radiation (a xenon lamp of 1500 W). With the aim of determining the contribution of UV-vis radiation to the browning phenomenon, two types of glass bottles were employed: topaz bottles (with low values of transmittance in the UV-visible range) and transparent bottles. To identify significant differences between the wine before and after being subjected to the influence of the UV-vis radiation, the values of absorbance at 420 nm and the concentrations of various polyphenolic and volatile compounds were submitted to a multivariate variance analysis. Both factors considered (time and type of bottle) had a statistically significant effect on the values of absorbance at 420 nm and on the concentration of most of the polyphenolic compounds, whereas only the "time" factor was significant for volatile compounds. All wines showed losses in several polyphenolic compounds, which were more severe for the wines bottled in transparent glasses. However, these wines exhibited a lower degree of visual browning (abs 420 nm). In the case of volatile compounds, most of these presented increases during storage exposed to the influence of the UV-vis radiation.

Study of Residual Particle Concentrations Generated by the Ultrasonic Nebulization of Deionized Water Stored in Different Container Types

A scanning mobility particle sizer has been used to quantify residual particle number and mass concentrations generated by ultrasonic nebulization of deionized (DI) water stored in a variety of bottles. High variability of residual particles was found not only between different bottle types but also between different bottles of the same type. Degradation of the water quality, quantified as increased residual mass and number concentrations as a function of time, occurred to varying degrees for water stored in different bottle types. Overall, glass bottles showed the highest residual particle concentrations and exhibited the poorest stability over time. After a storage period of 3 weeks, DI water stored in Pyrex bottles showed average increases in particle mass and number densities in the aerosol of over 250% and 60%, respectively. Total dissolved impurity levels in the water increased from 110 to 290 ng mL(-1) over the 3-week period. It is hypothesized that leaching from the bottle walls increases impurity levels in the water over time. Leaching was observed for both glass and polymer bottles. Contrary to this trend, residual particle concentrations from deionized water stored in Teflon bottles showed a net decrease during the measurement period. With respect to absolute residual particle concentrations and storage stability, a Teflon bottle yielded the best performance. Total residual particle mass and number densities for Teflon were less than a factor of 15% and 1%, respectively, as compared to residual particle levels observed for the Pyrex bottle. Absolute dissolved impurity levels in the water for the Teflon bottle decreased from 7.8 to 3.7 ng mL(-1) over the 4-week period.

Synthesis of unsaturated polyester resin from postconsumer PET bottles: Effect of type of glycol on characteristics of unsaturated polyester resin

AbstractPostconsumer PET bottles including water and soft‐drink bottles were depolymerized by glycolysis in excess glycols, such as ethylene glycol, propylene glycol, and diethylene glycol, in the presence of a zinc acetate catalyst. The obtained glycolyzed products were reacted with maleic anhydride and mixed with a styrene monomer to prepare unsaturated polyester (UPE) resins. These resins were cured using methyl ethyl ketone peroxide (MEKPO) as an initiator and cobalt octoate as an accelerator. The physical and mechanical properties of the cured samples were investigated. It was found that the type of glycol used in glycolysis had a significant effect on the characteristics of the uncured and cured UPE resins. Uncured EG‐based UPE resin was a soft solid at room temperature, whereas uncured PG‐ and DEG‐based resins were viscous liquids. In the case of the cured resins, the EG‐based product exhibited characteristics of a hard and brittle plastic, while the PG‐based product did not. The DEG‐based product exhibited characteristics of hard and brittle plastic after strain‐induced crystallization had occurred. In addition, it was also found that no separation of the type of bottles was needed before glycolysis, since UPE resins prepared from water bottles, soft‐drink bottles, and a mixture of both bottles showed the same characteristics. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 788–792, 2003

Use of anaerobically incubated media to increase yield of positive blood cultures in children.

During a 3-year period we received 10024 blood samples for culture from pediatric patients. Overall 181 episodes of significant bacteremia were documented. During the study period we would have missed 35 (19%) of all significant episodes of pediatric bloodstream infections if we had not been using the anaerobically incubated blood bottle. Anaerobically incubated blood samples are also necessary in the pediatric population.

Determination of alkylphenols, bisphenol A, benzophenone and phthalates in containers of baby food, and migration into food simulants

Infants, whose growth and development are highly dependent upon the endocrine system, are particularly vulnerable to endocrine disruptor exposure. In our study, we examined whether or not alkylphenols, bisphenol A, benzophenone, di(2-ethylhexyl)adipate and 10 phthalates are present in containers of baby food. Furthermore, the migration into food-simulating solvents was also examined. Sixteen types of containers of baby food, obtained on the Japanese market in 2001, were examined: 8 glass bottle types, 1 plastic type, 1 metallic package (laminated with plastic) and 6 multilayered laminated film packages. Alkylphenols, benzophenone, bisphenol A and di(2-ethylhexyl)adipate were not detected in any of the samples. On the other hand, dibutylphthalate (DBP) was detected in 7 samples (1.2-9.1 micrograms/sample), and di(2-ethylhexyl)phthalate (DEHP) was detected in 15 samples (1.3-18 micrograms/sample). Migration tests were carried out for 5 samples, and the levels of DBP and DEHP that migrated into n-heptane were 0.68-1.7 micrograms/sample and 0.33-3.5 micrograms/sample, respectively. From these results, a baby's intake levels of DBP and DEHP were estimated to be about 1/2,500 and 1/90-300 of the tolerable daily intake (TDI), respectively.

Diffusion and aggregation of Ag n-clusters ( n=2-9) on HOPG probed by fs-two-photon-photoemission

The diffusion and aggregation of preformed Agn-clusters ( n = 2-9) deposited onto a highly oriented pyrolytic graphite (HOPG) substrate is studied by two-photon-photoemission (2PPE). The sample is irradiated with ultrashort laser pulse pairs and the kinetic energy of the emitted photoelectrons is analyzed in a magnetic bottle type time-of-flight spectrometer. During annealing of the sample from 100 K up to room temperature, nanoparticles are formed on the surface by diffusion and aggregation of the silver clusters. A steep increase of the total photoelectron yield at a sample temperature of about 150 K is explained by the excitation of plasmons in the silver nanoparticles. From the kinetic energy distribution of the photoelectrons we deduce a strong variation of the work function of the sample during the formation of the nanoparticles, which is attributed to a quantum size effect.

Effects of UV on carbon assimilation of phytoplankton in a mixed water column

Carbon assimilation is usually measured at fairly constant light intensities. Under natural conditions, however, planktonic algae are moved through the water column and experience light of fluctuating intensity and spectral composition. They may cope with strong UV for a short residence in the upper water layer. In order to estimate the effects of UV on primary production of phytoplankton under conditions of turbulent mixing, we compared carbon assimilation and exudation of algae incubated in UV-transparent quartz and in UV-absorbing glass bottles which were moved through different water layers. Computer-controlled elevators were used to simulate mixing depths between 2 and 14 meters. Compared to the glass bottles, particulate C assimilation in the quartz bottles was reduced by 20-30 % at mixing depths between 2 and 10 m. There was no significant difference between both types of incubation bottles at a mixing depth of 14 m. Exudation was enhanced by UV near the water surface (mixing depth up to 4 m) but not in the deep-mixed samples. Our results indicate serious damage of planktonic algae by UV even under conditions of vertical mixing if the euphotic zone exceeds the mixing depth. Depression was low for circulation through the whole euphotic zone and may disappear at even deeper mixing. Our results indicate lower photoinhibition per UV dosage at fluctuating than at constant light intensities. A model predicting inhibition as function of weighted irradiance spectra was adapted to describe wavelength dependent photoinhibition occurring at different mixing depths. The model results agreed very well with the inhibition rates measured under fluctuating light. These preliminary results are used to discuss the importance of UV on photosynthesis of planktonic algae in aquatic environments of different mixing depths and stabilities of stratification.