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In this paper one new way how to surmount foregoing challenges will be described. The standard bottle and carboy shapes are well-known to us. They typically have a two-part shape, which is cylindrical (below) and conical (above) [1-3]. And we grew accustomed to it. Evidently, this is a very easy way to consume drinks (water, milk, cream, mayonnaise, beer, juice, oil, kefir and so on). I'm not interested in debating it. But...Every thing, in practise, has both positive and negative aspects [4]. There are at least two significant negative influences, in my view. For starters, because of the conical shape of bottles, we lose usable space that we can't use in practise. We are unable to tightly position one bottle on top of the other along the bottle's height (conical part disturbs us).The following is the second negative and significant event. Because of the conical shape of the container, there is typically a room in the narrow section where good goods can be stored without being used as food. The adhesion for products doesn’t play any negative role at all. Thin edible film helps us to save both products in full and keep the inner wall of bottle having rectangular or square shape clean too.

Freshly prepared apple tea wine (a combination of tea extract and apple juice) is having yeasty and dull flavour, which needs to be improved to increase the acceptability of this product. Therefore, an attempt has been made for artificial ageing of apple tea wine using different wood chips to improve its physico-chemical, sensory and antimicrobial attributes. Different types of wood chips (Quercus spp., Bombax spp. and Acacia spp.) were added respectively (2.5 g/L to the freshly prepared apple tea wine) and allowed for ageing in carboys for the six months at the room temperature. The influence of each wood species on physico-chemical, sensory and antimicrobial attributes was tested upto 6 months of storage. Storage intervals significantly affected all the physico-chemical attributes (except total sugars, volatile acidity, and antioxidant activity), whereas, the addition of wood chips affected titratable acidity, ethanol, higher alcohols, total phenols, and amino acid. Cluster analysis of the physico-chemical attributes data revealed the same and showed that storage intervals exerted more effect on the physico-chemical and antimicrobial properties of the apple tea wine rather than the wood chips. The antimicrobial activity of 6 months aged wine was low as compared to the fresh wine. Among all the wood chips, apple tea wine aged with Quercus spp. possesses a significantly higher score (according to desirability) than the wine aged with other wood chips and control. In nutshell, apple tea wine matured with Quercus spp. wood chips for 6 months were the best with improved physico-chemical and sensory attributes.

The relationship between bacterial load and the microalga Chaetoceros muelleri was analyzed in a scale-up experiment. The microalga was grown during five days in a 0.4-L Erlenmeyer flask, 2-L Fernbach flask, 18-L Carboy and 400-L column, during which the cell density of C. muelleri, the abundance of heterotrophic bacteria, Vibrio spp., and total bacteria were determined. The highest specific growth rates (μ) of C. muelleri occurred during the first day of culture (0.88 to 2.29 d-1). Highest cell density was recorded on the fifth day at the 2-L (7.62 × 106 cells·mL-1) and 18-L (6.32 × 106 cells·mL-1), coinciding with the maximum counts of heterotrophic bacteria (16.55 × 105 and >30 × 105 CFU·mL-1, respectively). There was a high correlation (0.80, 0.75, 0.85; p

Chaetoceros calcitrans is a small, fast-growing diatom with a high nutritional value for filter feeders. It is often used in hatcheries, particularly in the production of bivalve spat. It is widely produced in batch culture systems ranging from carboys to plastic bags to high volume tanks. Continuous culture of C. calcitrans has generally not been successful due to frequent crashes of the culture. We report the continuous culture of C. calcitrans in a hanging plastic bag system that is suitable for use in commercial hatcheries. Runs of continuous production lasted up to 125 d, with an average bag life of 24.4 d. Crashes occurred at irregular intervals in individual bags and caused the cell concentration to drop by up to three orders of magnitude. Cultures recovered over a few days following a crash. The temporary reduction of production due to crashes in individual bags was compensated by a 30% higher production than required. At dilution rates of 1.0–1.3 volume exchanges d − 1 the system produced 7–13 × 10 6 cells mL − 1 d − 1 . The cell diameter mode as determined by a Coulter Counter was 2.8–3.0 μm. The cells had the typical flat rectangular box shape with well-developed setae. The culturable bacterial population of the algae culture was 10 5 –10 7 colony forming units mL − 1 . Genetic integrity of C. calcitrans and monospecific status of the continuous culture were maintained over 7 sequential bag-to-bag transfers during a 125-day run. The fatty acid profiles of continuous and batch cultures of C. calcitrans were similar. Growth and survival of Greenshell™ mussel ( Perna canaliculus ) larvae were identical when fed with C. calcitrans batch culture or continuous culture delivered directly from the harvest line. When continuous culture was first collected over 24 h, diluted and then delivered to the rearing tanks over 24 h, larval growth was markedly slower (24 d to reach settlement competency compared to 21 d for the other two treatments); however the subsequent settlement success of competent larvae was not statistically different between the three diets (‘Carboy’, ‘Continuous/Harvest line’, ‘Continuous/Feed-out bin’; 33.9–35.5% settled). Concomitant to the differences in larval performance we observed a difference in larval fatty acid profile: lower-performing larvae had a markedly lower proportion of mono-unsaturated fatty acids and a markedly higher proportion of poly-unsaturated fatty acids. Lower performance and different fatty acid profiles of larvae fed the ‘Continuous/Feed-out bin’ diet appeared to be caused by unidentified changes that occurred during storage of the C. calcitrans culture.

RESUMEN. Algas y microalgas son productoras de compuestos antioxidantes como respuesta protectora al daño producido por estrés (radiación UV, variación de temperatura, iluminación excesiva, entre otros). En el presente estudio, se evaluó en condiciones de laboratorio el contenido de fenoles totales en cuatro especies de microalgas marinas: Chaetoceros muelleri (Lemmermann, 1898), Thalassiosira weissflogii (Grunow, 1977), Dunaliella tertiolecta (Butcher, 1959) y Tetraselmis chuii (Butcher, 1959), sometidas a diferentes condiciones de iluminación por efecto del material de las unidades de cultivo (recipientes de vidrio transparente y de plástico azul). Los fenoles totales fueron extraídos y se cuantificaron mediante espectrofotometría. Independiente de la condición de iluminación, el mayor número de células se encontró en D. tertiolecta y C. muelleri con 904.000 y 965.000 cél mL-1, respectivamente. La concentración de fenoles totales (mgEAG g-1 peso seco) fue diferente entre especies; sin embargo, no se encontraron diferencias significativas respecto a la condición de iluminación. Los extractos de D. tertiolecta cultivada en vidrio y T. chuii cultivada en plástico, mostraron el mayor contenido de fenoles (1,54 y 1,52 mgEAG g-1 peso seco, respectivamente). Se concluye que la producción de compuestos fenólicos fue mayor en los cultivos con microalgas verdes, independientemente de la condición de iluminación.

A bioreactor system for biotoxin production was appraised against traditional methods of growing dinoflagellate cultures. In an optimised bioreactor culture (5.4 L) operated in batch mode, growth of Karenia selliformis was more efficient than in 15-L bulk carboy culture in terms of growth rate (μ = 0.07 day−1 versus 0.05 day−1) and growth maximum (G max, 169.106 versus 41.106 cells L−1). Maximal gymnodimine concentration (1200 μg L−1) in bioreactor culture was 8-fold higher than in bulk carboy culture, and the yield per cell (pg cell−1) was 2-fold higher. Similarly the bioreactor batch culture of Alexandrium ostenfeldii performed more efficiently than carboy cultures in terms of growth rate (1.6-fold higher), growth maximum (15-fold higher) and desmethyl C spirolide (SPX-desMe-C) yield (5-fold higher [μg L−1], though the yield [pg cell−1basis] was lower). When bioreactor cultures of K. selliformis were operated in continuous mode, the yield of gymnodimine was substantially higher than a carboy or the bioreactor run in batch mode to growth max (793 μg day−1 over 58 days in continuous culture was achieved versus an average of 60 μg day−1 [carboy over 40 days] or 249 μg day−1 [batch mode] over 26 days). Likewise in continuous bioreactor cultures of A. ostenfeldii run over 25 days, the yield of SPX-desMe-C (29 μg day−1) was substantially higher than in same cultures run in batch mode or carboys (10.2 day−1 and 7.7 μg day−1 respectively). Similarly 5.4 L bioreactor batch cultures of K. brevisulcata reached 3.8-fold higher cell densities than carboy cultures, and when operated in continuous mode, the brevisulcatic acids were more efficiently produced than in batch culture (12 μg day−1 versus 7 μg day−1). When the bioreactor system was upscaled to 52 L, the maximum cell densities and toxin yields of K. brevisulcata cultures were somewhat less than those achieved in the smaller reactor, which was attributed to reduced light penetration.

A method based on isotope dilution headspace solid-phase microextraction and gas chromatography/mass spectrometry was used to assess levels of bisphenol A (BPA) in 56 samples of bottled water products sold in Canada. Levels of BPA in samples of all 51 non-polycarbonate (PC) bottled water products were lower than the method detection limit (0.50 µg l(-1)). Levels of BPA in most bottled water products in PC carboys were low, ranging from0.50 to 1.4 µg l(-1) with an average of 0.75 µg l(-1). However, BPA was detected at levels of 8.8 and 6.5 µg l(-1) in two bottles of the bottled water products in PC carboys from the same product analysed over a 5-week period, likely due to accidental or careless exposure of the products to heat (e.g. under the sun) during storage and/or transportation for extended periods of time.

Pavlova lutheri was cultivated in carboys using batch technique and in a flat alveolar photobioreactor (FAP), using initially batch and then semi-continuous techniques. Growth and productivity of the cultures were compared and their nutritional quality was assessed by analysing their biochemical composition (gross composition, fatty acids and sterols) and by evaluating their food value for Pacific oyster (Crassostrea gigas) larvae as bispecific diet in association with Chaetoceros calcitrans forma pumilum. The highest productivity was achieved with the FAP operating in semi-continuous mode. Gross composition of P. lutheri was similar in all cultures, while cellular organic matter content of the microalga grown in FAP in semi-continuous mode was lower. Significant differences in fatty acid content were detected with respect to the n-6 polyunsaturated fatty acid fraction, which was lower in cells cultivated in the FAP in semi-continuous mode. As concerns the main individual fatty acids, docosahexaenoic acid (DHA) content was higher in cells cultivated in the photobioreactor in batch mode than in carboys. The neutral lipid fraction contained seven principal sterols and the comparison among the cultures evidenced different proportions and different patterns. No differences were observed among larvae fed diets containing P. lutheri grown in carboys or in the FAP.

Phytoplankton bloom cycles were followed for 9 d in two 20 l carboy mesocosms filled with water from the offshore plume of Mobile Bay Alabama, USA, and incubated under fluorescent light. One of the blooms was enriched by addition of nitrate+phosphate (+nutrients), and both blooms were used to study how dimethylsulfide (DMS) concentrations and biological consumption varied over the bloom cycles. Peaks of algal biomass (15-22 µg chlorophyll a l-1) in the blooms were followed within 1 d by peaks of the DMS precursor, particulate dimethylsulfoniopropionate (DMSPp; 100-140 nM). DMS concentrations increased rapidly during the early bloom, rising from 1 nM on Day 1 up to 12 nM in the unamended carboy and up to 17 nM in the +nutrient carboy on Day 6. Maximum values for DMS concentrations, DMS consumption rates (as measured with 35S-DMS), and bacterial production were observed during the early decline of phytoplankton biomass. DMS consumption rates were initially 0.8 nM d-1 and increased to 3.1 nM d-1 in the unamended carboy and to 9.1 nM d-1 in the +nutrient carboy. Rate constants for DMS consumption (0.25-0.95 d-1) initially decreased as DMS concentrations increased, resulting in longer turnover times for DMS during the peak and early decline of the blooms. Assimilation of DMS-sulfur by bacterioplankton accounted for 4-22% of the total DMS consumption and higher rates of DMS assimilation occurred in the +nutrients bloom. Despite a bloom and decline of total heterotrophic bacterial abundances, bacterial community composition at the major phylogenetic group level remained relatively constant in both blooms, although the alpha proteobacteria showed a temporal increase in abundance in the +nutrient carboy. The concentration ratios of DMS:chlorophyll a and DMS:DMSP displayed non-linear, sigmoidal patterns over the bloom cycles and these ratios were not substantially affected by the nutrient amendment. Our results demonstrate that uncoupling of DMS production and biological consumption can occur early in a bloom cycle, causing DMS concentrations to rise significantly before biological consumption responds to draw down the DMS.

The Prymnesiophycea Pavlova lutheriwas produced using a traditional technique (batch mode in carboys) and by an innovative technique (semi-continuous mode in alveolarphotobioreactor). Two experimental feedingtrials were carried out with Pacific oyster(Crassostrea gigas) larvae with freshand preserved (4 °C and 1 °C)P. lutheri concentrates used inmonospecific and bispecific diets, incombination with fresh Chaetoceroscalcitrans forma pumilum. Nodifferences in terms of gross composition andlarval performance were noticed between thefresh algae biomass produced by the twotechniques. The low temperatures allowedpreservation of the nutritionalcharacteristics of the P. lutheri freshculture for the time period considered (27days). The P. lutheri concentratespreserved at 4 °C or 1 °C didnot differ substantially in terms ofnutritional value. Larvae fed a monospecificdiet of P. lutheri, both fresh andpreserved, exhibited a modest growth rate ( 4.5 µm day−1) and ahigh survival rate (>86%) were observed inlarvae. A substitution of 50% (trial 1) or80% (trial 2) of fresh C. calcitransforma pumilum with the preserved P. lutheri concentrates did not adverselyaffect growth rate or survival of C.gigas larvae.

We describe an economical 20 litre bench-top fermenter suitable for production of recombinant antibody fragments in bacterial expression systems. The bacterial culture contained within a polycarbonate carboy is mixed (400–600 rpm) and aerated (1 vessel vol./min) by a high-shear radial flow impeller mounted on a hollow stainless steel shaft, through which pressurised air is pumped. Air is dispersed as fine bubbles into the culture medium by the turbine impeller, without the need for a porous sparger. A stainless steel baffle stabilised by a gliding counterweight increases mixing. The components can easily be disassembled for cleaning and sterilisation. Temperature (range 20–37 °C) and pH (range 7.0–7.5) are controlled manually. Using the apparatus, it proved possible to achieve Escherichia coli cell culture densities equivalent to an optical density at 600 nm (OD600) of 30–32, compared with OD600 4–6 in shake flasks. A yield of 40 mg/litre/day of a recombinant antibody fragment was obtained with the fermenter, which was 15-fold more than the yield of 2.5 mg/litre/day achieved in shake flasks. The fermenter may be particularly suited for research purposes.

This study examined the effects of waste container handling on surface electromyographic activity of the erector spinae, infraspinatus and upper trapezius muscles, trunk kinematics (position, velocity and acceleration) measured in three planes (lateral, sagittal and transverse), spinal loading at the L5/S1 region and low back disorder (LBD) risk. Eleven field technicians at the Lawrence Livermore National Laboratory (LLNL) were asked to manipulate 30 and 55 gallon waste drums and carry a 5 gallon carboys in their workplace. Results showed that there was a statistically significant difference in muscle load on the erector spinae during drum handling activities. Loading and unloading the 55-gallon drums required more force from all muscle groups than the 35-gallon drums. Muscle peak load did not show a significant difference between 35 and 55 gallon drum rolling. For carboy transport, peak muscle activity is greater for all muscle groups with the two carboy carry. The calculated LBD risk also recognized the same activities as being most “at risk.” This data was used by the participatory team to focus their interventions and determine handling limits.

International audience; A simple steady-state model based on P-Limited bacterial growth rate and predator controlled bacterial biomass predicts bacterial production (BP) to be proportional to the square of ciliate biomass (C). Changes in ciliate biomass will then drive changes in bacterial production and carbon demand. This model was compared to experimental microcosms where natural mixed microbial communities from Villefranche Bay (northwest Mediterranean) were given daily additions of phosphate and glucose in a factorial design. In accordance with the proposed model, we found no effect of glucose additions on the incorporation of C-14-leucine, except when combined with phosphate. Phosphate enrichment had a stimulatory effect on bacterial production, even when no glucose was added, but after an initial phase of ca 2 d, leucine incorporation increased more in carboys receiving glucose and phosphate in combination than in carboys enriched with phosphate alone. After 3 to 4 d, leucine incorporation culminated. These observations are consistent with a scenario where, initially, bacterial growth rate was P-limited. Stimulation of bacterial carbon demand resulting from transfer of added phosphorus into ciliate biomass was, however, apparently larger than the increase in the system's production of labile organic C. The explanation suggested for the observed culmination in bacterial production is thus a switch from P- to C-limited bacterial growth rate. In such a scenario, glucose addition allows a larger increase in bacterial consumption before the pool of labile DOC is depleted. DOC accumulation was found only in carboys to which glucose was added without phosphate.

The cellulose-acetate membrane (CAM)-filter dissolution method implemented into a Millipore Glass Microanalysis system was used for recovery of Cryptosporidium parvum oocysts seeded into 25 l of drinking water in polyethylene carboy aspirator bottles. CAM-entrapped oocysts were detected by immunofluorescence microscopy. From 65 to 94 oocysts/l (mean 75 oocysts/l), 34.7% overall of the inoculated oocysts, were unrecovered as determined after the water had been drained from the bottle, rinsed with 1 l of eluting fluid (EF), and CAM-filtered. Efficiency rates of oocyst recovery ranged from 24.0% to 64.0% (mean 44.1%), without the use of EF and from 72.1% to 82.3% (mean 78.8%) when EF was used. To ensure a high recovery efficiency of Cryptosporidium oocysts from sampled water by the CAM-filter dissolution method, it is recommended that 1 l of EF per 25 l of water be used.

We compared the effects of substrate C:N ratio and macrozooplankton activity on nutrient and chlorophyll dynamics by amending the substrate C:N ratios in carboys conta in~ng natural estuarine microplankton [

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:25:57Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:47:17Z : No. of bitstreams: 1 2-s2.0-79961043141.pdf: 598045 bytes, checksum: 86135c6ef953b631e2f88dd19dc8cf81 (MD5) Made available in DSpace on 2014-05-27T11:25:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-08 A laboratory culture of Ankistrodesmus gracilis algae was evaluated by studying the biology of the species and its chemical composition in a traditional medium (CHU 12) and in two alternative culture media, NPK (20-5-20) and macrophyte (Eichhornia crassipes) + NPK, in three different types of recipients (fiberglass, carboy and plastic bag). First peak in the growth curve of Ankistrodesmus gracilis occurred on the ninth day in macrophyte + NPK medium (74.16 x 10 5 cells mL -1) in a fiberglass recipient. However, highest density (p < 0.01) was reported in medium CHU 12 (122.87 x 10 5 cells mL -1) in a plastic bag on the twelfth day. Cell density was over 70 x 10 5 cells mL -1 starting on the twelfth day. Growth rate of A. gracilis was similar (p > 0.05) in culture media in the three recipients. Protein and fiber were similar (p > 0.05) in the treatments, but lipids were higher (p < 0.05) in NPK. Nitrate, ammonia, total phosphorus and orthophosphate contents were over 1 mg L -1 in NPK (p < 0.01). Results show that alternative media, such as NPK and macrophyte + NPK, are possible for large-scale culture of A. gracilis cultured in three types of recipients. Costs are low, occupying less space when cultured in plastic bags and in the laboratory. Laboratório de Limnologia e Produção de Plâncton Centro de Aquicultura Universidade Estadual Paulista, Via de Acesso Prof. Paulo D, Castellane, s/n, 14884-900 Jaboticabal, SP Instituto de Biociências Departamento de Zoologia Universidade Estadual Paulista, Rio Claro, SP Laboratório de Limnologia e Produção de Plâncton Centro de Aquicultura Universidade Estadual Paulista, Via de Acesso Prof. Paulo D, Castellane, s/n, 14884-900 Jaboticabal, SP Instituto de Biociências Departamento de Zoologia Universidade Estadual Paulista, Rio Claro, SP

The feasibility of growth, calcium carbonate and lipid production of the coccolithophorid algae (Prymnesiophyceae), Pleurochrysis carterae, Emiliania huxleyi, and Gephyrocapsa oceanica, was investigated in plate, carboy, airlift, and tubular photobioreactors. The plate photobioreactor was the most promising closed cultivation system. All species could be grown in the carboy photobioreactor. However, P. carterae was the only species which grew in an airlift photobioreactor. Despite several attempts to grow these coccolithophorid species in the tubular photobioreactor (Biocoil), including modification of the airlift and sparger design, no net growth could be achieved. The shear produced by turbulence and bubble effects are the most likely reasons for this failure to grow in the Biocoil. The highest total dry weight, lipid and calcium carbonate productivities achieved by P. carterae in the plate photobioreactors were 0.54, 0.12, and 0.06gL-1day-1 respectively. Irrespective of the type of photobioreactor, the productivities were P. carterae>E. huxleyi>G. oceanica. Pleurochrysis carterae lipid (20-25% of dry weight) and calcium carbonate (11-12% of dry weight) contents were also the highest of all species tested. © 2011 Wiley Periodicals, Inc.

Packaging fulfills several important functions in the safe delivery of chemical products through the distribution system to customers: containment, protection, use features, and communication. Development of industrial packaging with these functions in mind is critical for the safe efficient delivery of industrial products. There are many regulations making demands on package development, including domestic rail and motor freight classifications as well as other carrier requirements, and U. N. recommendations for international transport of dangerous goods (perhaps virtually all chemicals), which are restated in U.S. Department of Transportation regulations. Many types and sizes of industrial packages for chemicals are in use, ranging from small boxes, pails, and drums, through intermediate bulk containers, to specialized rail cars. The variety of packaging alternatives, sizes, materials, and applications are all discussed. Keywords: packaging; regulations; bulk handling; hazardous materials; steel drums; pails; plastic drums; wooden barrels; fiber drums; bags; laminated textiles; carboys; bottles; boxes

There is an urgent need for natural water reference materials certified for nutrients. In 1996, NRC collected seawater for a proposed CRM at a depth of 200 m in the North Atlantic; this was immediately filtered through 0.05-microm cartridge filters into 50-L carboys. The water was later homogenized in the NRC laboratories in Ottawa and stabilized via gamma irradiation. Over six years of stability testing no significant deterioration was detected. In addition to the usual customary standard colorimetric procedures, alternative analytical methods were developed to enable the certification process. The production of a CRM called MOOS-1 will be discussed. Certified values, with uncertainty components addressing the homogeneity, stability, and characterization of the material, were calculated to be: orthophosphate=1.56+/-0.07 micro mol L(-1), silicate=26.0+/-1.0 micro mol L(-1), nitrite=3.06+/-0.15 micro mol L(-1), and nitrite and nitrate=23.7+/-0.9 micro mol L(-1).

Publisher Summary This chapter discusses the culture of groupers. Groupers are the marine finfish belonging to the subfamily Epinephelinae and they are widely distributed in the tropical and subtropical coastal waters. In Asia, the culture of groupers in floating net cages is normally practiced along sheltered coastal regions and the main species of groupers cultured in Asia are Epinephelus coioides, E. malabaricus and E. lanceolatus. The majority of grouper seeds are obtained from the wild, with some produced in hatcheries. The culture of groupers can be divided into three stages: the hatchery/larval, nursery and the grow-out stage. Different skills are required in each of these three stages of grouper culture to ensure a high survival of healthy groupers. At the hatchery/larval stage, the larvae are maintained in either cement or fiberglass tank with constant moderate aeration. The nursery stage is carried out in ponds, cement or fiberglass tanks as well as net cages, which are kept afloat with styrofoam and plastic carboys in rivers. The grow-out groupers are usually placed in floating net cages, cement tanks or earthen ponds.

The principal shipping containers are made of wood, fibreboard and metal. Glass is still sometimes used for carboys for corrosive liquids such as acids, etchants and other chemicals, but the quantities are small and the carboy must be well protected in another pack. Wood is normally used when the package is large or the product is of high density. Thus timber cases and crates are used extensively for weights above 100 kg (2201b); below this weight, fibreboard (both solid and corrugated) is the favoured material. Timber is also used for wine and beer casks, but there is a trend toward its replacement by metal (stainless steel or aluminium), either alone or with inner liners of plastic.

Since membrane potential regulates the activity of nerves, muscle, and endocrine cells, and many drugs alter the membrane potential, an understanding of the general concepts for the regulation of membrane potential is important. Yet, membrane potentials and ion gradients are often tough areas for students to understand. Analogies can be helpful; for example, Cardozo (2) recently provided a spring analogy for membrane potential. However, in my experience, part of the difficulty probably relates to an adverse reaction to physics and math terms; another part of the problem is just the new technical terms that make it difficult for the students to decipher the concepts. For some of these students, springs may not be enough of an improvement. I have found that a qualitative understanding is facilitated by providing a demonstration and a series of analogies. These analogies will quickly help the students understand the different ways in which a cell can be depolarized (opening Na channels or closing K channels) and hyperpolarized (opening additional K channels or closing Na channels). The analogy is to consider the color of solution in a clear bucket as representing the membrane potential. Two carboys, one filled with blue solution and one with red solution, have tubes that lead to the bucket. The blue solution represents the K gradient, and the red solution represents the Na gradient. The rate of flow of fluid, governed by the valve, reflects the conductance. For most cells, the resting potential is pretty close to the K equilibrium potential, so the flow from the blue solution into the bucket is much greater than that from the red solution and the bucket is slightly purple‐but mostly blue. I then ask the class how I can depolarize the bucket, that is, how can I make the solution more purple (or even red). They all immediately see that opening up the valve from the red solution (opening Na channels) will do it. Then, I ask “what other way is there?” After a few moments of thought, they realize that closing K channels (reducing the flow from the blue solution) also works, which is how pancreatic -cells depolarize. One can extend the analogy to cover Cl channels. It is probably worthwhile to remind the students that this analogy is just an approximation and not to overinterpret this color analogy. To extend the analogy, a third carboy (the Cl gradient) is introduced; it can be merely a virtual carboy because the students can quickly pick this up after having seen the original demonstration. It is important to stress at this point that the Cl gradient differs in each cell, and so the color of this third carboy is cell dependent. For skeletal muscle cells, it is the same color purple as the resting membrane potential (which is mostly blue and a bit of red). At this point, one may want to talk about fainting goats (1), including showing a short YouTube video. These goats have reduced Cl channel activity in their muscle cells, and thus the muscle membrane potential is less stable. In wild-type goat muscle cells, the valve is substantially open. This does not change the color of the solution in the bucket. But, the class will quickly realize that one has to really open the red carboy valve (Na channels) to get the bucket solution to change color. However, in the fainting goats, the valve from the third carboy (Cl channels) is almost closed, and so a small change in Na conductance can drastically change the color of the bucket solution. In other cells, the Cl gradient can be either more blue than the resting purple membrane potential or more red. Thus, when the Cl channel opens, the direction of the change of membrane potential (more blue, more hyperpolarized; more red, more depolarized) depends on the color of the Cl gradient. One can even push the analogy further and talk about cells or conditions where the Na and K gradients change. A smaller K gradient can be represented by a lighter blue solution in the carboy. This means that, even when the valves on the Na and K carboys are not changed, the resting potential is more reddish than when the K gradient was larger (the carboy had a darker blue solution).

A solution is presented for the problem of filling a storage carboy with deionized water without the need for annoying reminders to close the faucet valve. A solenoid-activated valve, regulated by a spring-wound timer switch, is installed in line between the faucet and deionizing column. Existing systems can be retrofitted for under $100. The device allows for carefree filling of the carboy without flooding.

Diapausing tobacco budworm, Heltothis virescens F., pupae were stored underground in one of three different containers: 30-ml plastic cups (housed in 10.0-liter carboy) containing either sand, corncob grit, or 2% agar; 1.0-liter plastic containers containing sand; or 10.0-liter carboys containing 2% agar and corncob grit. Control pupae were stored in plastic Petri dishes in an environmental chamber at 1°C. Pupae were exhumed after 110 d. Samples from each treatment were placed in a diapause termination environment (27°C and constant light). Ninety percent of the control pupae emerged as adults. Of the pupae stored underground, those stored in 30-ml plastic cups containing either sand or agar had the highest percent emergence (68%).

Using a plug-flow reactor we have been able to demonstrate the conversion of pure methane gas to liquid hydrocarbons via the intermediate formation of methanol. The reaction Was carried out at an intermediate pressure (about 20 atm) and moderate temperature (about 400°C). In the first stage of the reactor methane and oxygen react to produce methanol. In the second stage the methanol was converted by HZSM-5 catalyst to a mixture of hydrocarbons. Analysis of the reaction products showed that all of the oxygen Was used in the reaction. Apart from the unconverted methane the product was composed of oxides of carboy water and C3+ hydrocarbons. Interestingly, among the liquid hydrocarbons, aromatics were found to be the major constituents.

The macroalga Gracilaria tikvahiae (Rhodophyta) was used in a closed system of materials to study methane production and nitrogen recycling. Twenty liter carboys served as digesters. The performance of these digesters mirrors results obtained with two- and four-litre Gracilaria digesters with respect to optimal retention times for biogas production, methane content, and bioconversion efficiency to methane. Three groups of Gracilaria were cultivated in 850-L vaults to compare growth performance under three different enrichment treatments. These treatments consisted of an unfertilized group, a group raised on a typical commercial enrichment regime, and a group raised on the residues removed from the digester when additional substrate was loaded into the digester. The results indicate that growth of Gracilaria on the digester residue enrichment scheme is statistically similar to growth using a commercial enrichment mixture. In addition, the nitrogen content of the digester residue is described, along with nitrogen assimilation by Gracilaria and nitrogen recycling efficiencies. Both nitrogen assimilation and recycling efficiency closely parallel the ammonium content of the residue enrichment media.

Two algal flagellates, Dunaliella tertiolecta Butcher and Tetraselmis maculata Butcher, harvested in the stationary phase from a semi-continuous carboy culture apparatus, were analyzed for dry weight, total carbohydrate, total protein, and total lipid. Each species was cultured in three different growth media. The growth response of D. tertiolecta was similar in all three formulations but populations of T. maculata were considerably limited in the reduced-nutrient medium, X1. Both algal species cultured in the X1 medium had significantly greater dry weights and contained more carbohydrate and less protein than cells cultured in the standard formulation (E). A third formulation (N/P), in which all medium components were reduced except nitrate and phosphate, produced algae with reduced carbohydrate and increased protein as compared with E medium. The total lipid content of D. tertiolecta was significantly less than that of T. maculata regardless of the culture medium.Algae cultured in the three formulations...

A 5-day old, 15 per cent (v/v) spearmint cell inoculum in a dual-carboy system containing modified T-medium with 2,4-dichlorophenoxyacetic acid (0.5 p.p.m.), Dow Corning-B antifoam (500 p.p.m.), and bacitracin (5 p.p.m.) is suggested for good cell suspension growth.

HYDROGEN PEROXIDE Being both an oxidizing and a reducing agent, hydrogen peroxide adapts itself to a wide variety of chemical production techniques. Highly specialized structural materials and design characterize the equipment used in its manufacture. HYDROGEN PEROXIDE in dilute solutions has been a commercial chemical for nearly a century; however, it was not until about 1925 that concentrated solutions were produced in this country. Since then hydrogen peroxide in concentrations of 30 to 40 grams H 2 O 2 per 100 cc. has graduated from a laboratory curiosity supplied in ceresin wax bottles to an industrial product shipped in carboys, drums, and tank cars. Appropriately designated as "oxidized water" by its discoverer, Thenard, hydrogen peroxide was first prepared in 1808 by the action of an inorganic acid on barium peroxide; this reaction is still the basis of a commercial production process. With the development of electrolytic methods, hydrogen peroxide acquired greater commercial significance. Today m...

Rhincalunus nusutus was cultured through seven consecutive generations in 19-liter carboys when provided with a mixture of diatoms and Artcnzia salina nauplii as food. The mean generation length was 8.7 weeks, similar to that of the local field population of this species during some seasons. Fecundity of laboratory-reared animals was lower than that of the field population. Instantaneous coefficients of individual exponential growth ( k in the expression, Wt = Woekt,where W is body weight of organic carbon and t is days) were 0.24 to 0.12/day, depending on the age of the individual. About 10 pg of detrital carbon were produced as exuviae during the growth of an individual. Even young nauplii fed preferentially on large food particles. The suggestion that the copepods' first antennae are used in the feeding process was not supported by an experimental test. R. nusutus nauplii are apparently active enough to avoid being eaten by their parents.

Measurements of gross photosynthesis; respiration, rate of net oxygen diffusion, and organic storage are reported for 7 microcosms maintained over periods of 5 to 7 months. Average rates of gross photosynthesis ranged from 0.86 to 1.69 g Oz/m2/day and were related to the amounts of inorganic nutrients added. Average final organic storage was equal to 35.6% of gross photosynthesis. Assumed photosynthetic quotients between 0.88 and 1.03 allowed the construction of oxygen budgets in which the total product of gross photosynthesis was accounted for. Some problems of establishing productive microcosms representing natural situations are also discussed.

A convenient method is described for the production of up to 1.75 g of citrinin per liter by Penicillium citrinum growing in stationary culture in a 5-gallon (18.925 liters) carboy containing 4 liters of 4% sucrose and 2% yeast extract medium.

The Acitainer (Acid container), designed and manufactured by Harcostar Ltd, Huntingdon, is a 45 1 (10-gal.) low-density polyethylene (LDPE) container enclosed and protected by a high-density polyethylene (HDPE) outer container. Both inner and outer containers are blow moulded and the combined unit offers a safer alternative to the conventional acid-carrying carboy.

For most natural water, a large sample is required to provide the 3 grams of carbon needed for a carbon-14 determination. A field procedure for isolating total dissolved-carbonate species is described. Carbon dioxide gas is evolved by adding sulfuric acid to the water sample; the gas is then collected in a sodium hydroxide trap by recycling in a closed system. The trap is then transported to the dating laboratory where the carbon-14 is counted. INTRODUCTION An assessment of the carbon-14 concentration of water in various parts of hydrologic systems is useful in determining both direc tion and rate of water movement. Current interest in carbon-14 measurements has necessitated the development of a field procedure for isolating total dissolved-carbonate species from water systems. This paper describes an adequate yet simple method for readily accomplishing the isolation. The authors acknowledge the early work by L.L. Thatcher and C. W. Naeser on the water sample preparation technique and thank Irving May for measuring CO 2 content of NaOH traps used in determining the efficiency of the apparatus shown in figure 1. PRINCIPLES OF ISOLATION Sulfuric acid added to water samples liberates dissolved-carbonate species as carbon dioxide gas. The evolved gas is collected in a sodium hydroxide trap by recycling in a closed system. For most natural water, a large sample is necessary to provide the minimum of 3 g of carbon required for an age determination by counting. Polyethylene bags manufactured for use by dairy companies in transporting liquids are suitable for collecting largevolume water samples. These two-ply lightweight containers, designed to hold as much as 6 gallons each, are supported by a cardboard carton provided with the bag. Water is removed without bubbling because the bags collapse as they are emptied; thus air contamination is minimized. Polyethylene carboys bound in plywood have also been used in sample collection and have served as the gas evolution flask during carbonate isolation. When collecting ground water, adequate care must be taken to reduce air contamination of the sample and to pump the well until a representative sample of formation water is assured. The apparatus shown in figure 1 was used to obtain sequential evolutions of CO2 from carefully weighed reagent-grade Na^COg standards. The overall efficiency of the procedure was determined using a gas-flow rate of approximately 30 cc per sec, In practice, screw compressor clamps on rubber connection lines were used to control the gasflow rate. Percent of CC>2 recovery as a function of cycle time is plotted on figure 2. To attain a minimum of 90 percent CC>2 recovery, the minimum cycle period should be 150 minutes when using a 5-gallon evolution flask and 180 minutes when using the 13-gallon carboy.

Publisher Summary This chapter discusses the purification and standardization of water for tissue culture. The most common method for purifying water in small laboratories is demineralization or distillation or a combination of both. For the average tissue culture laboratory, an efficient system for obtaining high purity water would be a mixed bed ion exchanger followed by a glass still. Plastic carboys are the most common water storage vessels in tissue culture laboratories. These have been the source of a wide range of problems. There are a wide variety of plastics in use but they all have in common the disadvantage of being porous. Conductivity is the easiest and most frequently used method for determining water purity. An indicator light, or series of lights which go off at certain levels of resistivity, or a monitoring meter may be used. If water is suspected as a contribution of toxicity, or if ion exchanger-still function is to be tested, any of several standard methods texts available in most libraries may be consulted.

Since growth of cool season grasses is more related to soil temperatures than air temperatures, a method was developed for independent control of soil and air temperatures utilizing a modified chest-type freezer placed inside a controlled environment growth chamber. The freezer door was replaced with a plywood top insulated with styrofoam. Pots containing two cultivars of Poa pratensis L. were suspended through holes in the top into the freezer chamber and root zone temperature was controlled utilizing a sensitive thermostat. Carboys containing nutrient solution were placed in the chamber and subirrigation was accomplished by pressurizing the carboys with an air pump. The temperature of the material in the pots reached equilibrium with the freezer environment in 4 hours. The system was effective in controlling root-zone temperatures at optimum for shoot growth (22 C) during a 10-week period where ambient temperatures were increased in 4 C increments every 2 weeks from 22 C to 38 C. The system could be used wherever growth or physiological responses to soil temperature must be separated from responses to air temperature.

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(1954). Converting Carboys into Jars and Aquaria. The Progressive Fish-Culturist: Vol. 16, No. 3, pp. 139-140.

The growth rate of plant tissue cultures is substantially increased through the use of a large-volume carboy system. Aeration is considered to be the most important factor. With this system, yields of a pound or more of tissue can be obtained within 2 weeks.

IN work carried out by the British Non-Ferrous Metals Research Association on the corrosion of metals by domestic waters, glassware used for sampling water and for carrying out corrosion tests was coated with paraffin wax to prevent pick-up of alkali silicates. Tests carried out in waxed containers, or with water conveyed in them, gave inconsistent and non-reproducible results. It was observed from time to time that the wax coatings of some of the carboys were attacked and gradually disintegrated. In view of our previous experience of bacteria in altering the corrosive properties of waters, the possibility of bacterial action was considered.

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The effects of food quality, competition, or potentially toxic substances on the growth and survival of Daphnia can be determined by renewing food daily in a small container or by continuously providing food with a flow through system. Sedimentation and grazing in containers will lower food concentration to below the experimental level. Daphnia pulex fed at low food concentrations in a simple continuous flow system grew more than those fed in small containers. The growth of Daphnia pulex will be underestimated if the feeding suspension is supplied in daily renewals. The water flea, Daphnia, is used in the assessment of the toxicity of various substances and in studies of the effect of food quality and competition on individual or population growth (Goulden et al., 1982a, 1982b; LeBlanc, 1980; Schwartz and Ballinger, 1980; Winner et al., 1977). In such experiments, Daphnia are grown in beakers, or some similar container, and transferred at discrete intervals, usually daily, into fresh feeding suspensions. The actual cell concentration in these static renewal experiments will be lowered from that expected during the course of the day because of sedimentation and grazing. The absolute amount of food (cells/day) provided to test organisms in a continuous flow system that maintains ambient food concentration will be in excess of that in a static renewal system (Attar and Maly, 1982; Lampert, 1976). As a result, life table or feeding experiments conducted with static renewal techniques could underestimate growth and survival. At least three studies have used continuous flow systems. Attar and Maly (1982) flowed suspensions through large tanks containing smaller chambers within them, but lost the advantage of true replicates of individual organisms. IPresent address: Division of Environment, Kansas Department of Health and Environment, Topeka, Kansas 66620. This content downloaded from 157.55.39.117 on Fri, 15 Jul 2016 05:55:13 UTC All use subject to http://about.jstor.org/terms VOLUME 89, NUMBERS 3-4 91 Other sophisticated designs (Lampert, 1976; Novak et al., 1982) had true replicates, but required the use of expensive equipment. The objective of this research was to document the differences in daphnid growth between static renewal and continuous flow techniques, design and use an inexpensive and simple method of performing a continuous flow experiment, and consider the relationship between food availability in the laboratory and that in the field. MATERIALS AND METHODS Continuous flow system. Each unit of the flow system had a 20-liter polyethylene carboy with an overhead stirrer connected to a timer that controlled stirring (5 min/h) to prevent sedimentation. Aquarium tubing, fitted with pinch clamps, fit snugly into six reducing connectors glued into holes at the base of the carboy. The tubing served as outlets. A length of aquarium tubing connected the carboy outlet to the inlet port of an experimental feeding tube. The two sections of tubing were connected by a small plastic pipette tip with the narrow end cut off to form a larger aperture. Six (6) experimental feeding tubes were part of each unit. Feeding culture tubes (55 ml volume) fitted with 4 mm o.d. glass tubing as an inlet (just below shoulder of tube) and an outlet (out of base). The inside of each opening was covered with 0.10 mm nylon mesh, attached with silicon sealer. A short piece of aquarium tubing with a pipette tip was placed over the inlet port and received the connector tubing. Another piece of aquarium tubing connected the vessel outlet to a glass tube "antler" that collected the water from the six vessels into one outflow. That outflow was controlled by a pinch clamp and a plastic valve that provided the small degree of flow control needed. Static renewal system. The static renewal treatments consisted of 100 ml of suspension in a 150 ml beaker (6 replicates). Experimental design. Experiments were performed at two cell concentrations of Chlorella vulgaris: 1 x 104 and 5 x 104 cells/ml. Two flow rates, described later, were used at each cell concentration to increase cell availability. The first of two controls was an unfed treatment in beakers. The second control was in the flow tubes, but with no flow, to determine differences that were independent of the rate of flow between beaker and tubes. Animals. At each cell concentration, each experiment began with Daphnia pulex

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The Denver Fire Department was called to the office of theDenverPost Sept. 20, 1904, at 4 p. m. On arrival they were informed that a carboy of nitric acid had been accidentally broken in an attempt to remove the stopper with a hammer. The acid spread across the floor, coming in contact with the zinc used in etching. Sawdust was used to absorb it, and, rapidly oxidizing, burst into flame here and there, resulting in the call for the firemen. Mr. Bradt, foreman of the department, who was at work in the room, states that the fumes and smoke were not especially irritating until the portable apparatus began playing on the fire, the usual carbonic acid-producing solutions being employed. We find by examination that the acid used contained no appreciable amount of nitrous acid and was of about 38 per cent. strength. About ten gallons of it escaped