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Collection methods for micro- and meiofauna within high shore splashpools are compared using four simple, hand-held devices, with the supralittoral harpacticoid copepod Tigriopus califoricus as a representative organism. For the collection of all T. califarnicus life-history stages, over a range of potential densities and with a minimum of specimen damage, a 30 ml graduated pipette is demonstrably more efficient than bottles, preparation dishes, or small nets. Collection ofnauplii and gravid females, which typically subsist closer to the substratum and in pits or crevices in the bedrock, was particularly better using the pipette, which generates a rapid suction, produces less overall disturbance than larger devices, and can be used over a broad range of pool sizes without modification. For analysis, pipettes provide a smaller, more concentrated sample, reducing processing time and the potential for handling error.

Made available in DSpace on 2014-10-01T13:08:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-12-01Bitstream added on 2014-10-01T14:04:08Z : No. of bitstreams: 1 S0100-69162013000600020.pdf: 192723 bytes, checksum: 82744f3427e5af19cff706cc8bdb9686 (MD5) O ar incluído em gotas geradas por pontas de pulverização interfere diretamente em seu transporte e deposição, influenciando também na retenção das mesmas após o impacto no alvo. O objetivo deste trabalho foi verificar a interferência de adjuvantes na quantidade de ar incluído em gotas geradas por pontas de pulverização. Os tratamentos utilizados corresponderam a soluções contendo: óleo mineral, óleo vegetal, surfatante e água, aplicados com três tipos de pontas de pulverização, sendo duas com indução de ar e uma com pré-orifício. O ar incluído foi calculado através da diferença entre o volume da mistura pulverizada (ar mais líquido) e apenas o líquido, que foi feito por meio de amostras pulverizadas, capturadas em um funil e coletadas em proveta graduada. A tensão superficial foi estimada através do método gravimétrico, utilizando uma balança de precisão e uma bureta graduada. O surfatante foi o que proporcionou maior porcentagem de ar incluído na pulverização. Para a tensão superficial, as caldas contendo óleo mineral e o surfatante tiveram os menores valores. Os resultados mostraram que o uso de adjuvantes tem influência direta na porcentagem de ar incluído. Além disso, adjuvantes com maior capacidade de redução da tensão superficial e que formam misturas mais homogêneas proporcionaram aumento da porcentagem de ar incluído nas gotas pulverizadas. The air included in droplets generated by spray nozzles directly int0erferes in transport, deposition and retention of the droplets after its impact on the target. The objective of this study was to analyze the interference of adjuvants in the amount of air included in droplets generated by spray nozzles. The treatments were composed by four spray solutions containing mineral oil, vegetable oil, surfactant and water, and three spray nozzles, two air induction type and one pre-orifice. The air included was calculated by the difference between the volume of spray mix (air plus liquid) and only the liquid, which was made by means of sprayed samples captured in a funnel and collected in a graduated cylinder. The surface tension was estimated by the gravimetric method using a precision scale and a graduated pipette. The surfactant provided the largest percentage of air included in the spray. For the surface tension, the mineral oil and the surfactant had the lowest values. It was concluded that the use of adjuvants had a direct influence on the percentage of air included. In addition, products with greater ability to reduce surface tension and to form homogeneous solutions provided the increase in the percentage of air included in the droplet. UNESP FCA Depto. de Engenharia Rural Universidade Estadual Paulista Faculdade de Ciências Agronômicas Depto. de Engenharia Rural Universidade Estadual do Norte do Paraná UNESP FCA Depto. de Engenharia Rural Universidade Estadual Paulista Faculdade de Ciências Agronômicas Depto. de Engenharia Rural

A multi-centre study was undertaken to: a/ determine the density of human semen, and b/ assess the validity of measuring semen volume either volumetrically or gravimetrically. Semen samples from four clinical categories (azoospermia following vasectomy, azoospermia without vasectomy, oligozoospermia (20x10(6)/ml) and normozoospermia (/=20x10(6)/ml)) had similar densities (one-way ANOVA: F(3,180)=1.25, not significant), being close to 1.0 g/ml when taken to one decimal place. Measurement of semen volume was then made with either a graduated pipette or by weighing and assuming a density of 1 g/ml. A comparison of the two methods gave an excellent correlation, with a gradient of 1.0571 and a coefficient of determination (R(2)) of 0.98 (p0.0001). However, it was noted that the aspiration of the ejaculate in to a graduated pipette underestimated the volume by approximately 0.2 ml, but in an inconsistent manner making the use of a set correction factor inappropriate. The estimation of volume to one decimal place by weighing the collection container before and after ejaculation, assuming a density of 1 g/ml, would seem to be a viable alternative although the density of a small number of samples may deviate from this assumption. Whilst the relatively small underestimation of volume with a pipette is unlikely to have clinical significance, the known reporting of inaccurate results by a laboratory is contrary to the philosophy and key principles of quality management.

An instrument is described by which aliquot portions of a liquid may be mechanically measured and delivered. It was devised especially for use in immunological experiments, to take the place of a graduated pipette in setting up serum tests. The instrument may be set for any quantity within its capacity and measures sterile liquids without danger of contamination. It may therefore find a wider application in other procedures requiring sterile measurements of small amounts of liquid.

A neutron dosemeter which offers instant read-out has been developed for nuclear criticality accidents. The system is based on gels containing emulsions of superheated dichlorodifluoromethane droplets, which vaporise into bubbles upon neutron irradiation. The expansion of these bubbles displaces an equivalent volume of gel into a graduated pipette, providing an immediate measure of the dose. Instant read-out is achieved using an array of transmissive optical sensors which consist of coupled LED emitters and phototransistor receivers. When the gel displaced in the pipette crosses the sensing region of the photomicrosensors, it generates a signal collected on a computer through a dedicated acquisition board. The performance of the device was tested during the 2002 International Accident Dosimetry Intercomparison in Valduc, France. The dosemeter was able to follow the initial dose gradient of a simulated accident, providing accurate values of neutron kerma; however, the emulsion was rapidly depleted of all its drops. A model of the depletion effects was developed and it indicates that an adequate dynamic range of the dose response can be achieved by using emulsions of smaller droplets.

The accuracy of drug delivery by drop-counting infusion pumps depends among other considerations, on the assumption that drop volume is constant. This assumption may hold true in most cases, except for surface active agents. Lowering the surface tension causes drop size reduction and a decrease in actual drug flow when delivered by drop-counting infusion pumps. To determine the number of drops per milliliter of intravenous solutions, a system comprising an infusion set connected to the bottom of a vertically mounted 5-ml graduated pipette has been developed. A device containing a light source and a photoelectric cell was interfaced to an Atari 104ST microcomputer by means of an analog-to-digital converter and then attached to the filter of the infusion set. An assembler routine detected the falling drops and a main BASIC program calculated the cumulative number of drops and the instantaneous drop rate. Preliminary experience showed that this surface tension lowering effect may account for decreases of up to about 25% in drug delivery when drop-counting infusion pumps are used and thus may have practical clinical consequences. >

The rennet activity of chymo-trypsin (or pepsin) is conveniently measured by allowing a standard solution of milk to which chymotrypsin has been added to flow slowly through a graduated pipette and observing the rate and distance of flow of the milk before it clots. The time required for chymo-trypsin to clot milk may be calculated from these observations. The rennet activity is expressed as the reciprocal of the time in minutes required for 1 ml. of enzyme solution to clot 10 ml. of standard milk powder solution.

For the purpose of measuring the salt content of the waters of Back Bay, Virginia, and Currituck Sound, North Carolina, as related to the distribution of different kinds of water plants commonly used for food by ducks and geese, a quick and convenient method for determining the salt content of the water was needed. Since the area to be examined was large, approximately 30 miles long and IO miles wide, a method that could be adapted to use in a motor boat, even while the motor boat was in motion, was wanted. This requirement made it impossible to use a hydrometer since with this instrumiient absence of any jarring motion is necessary. An important requirement for preliminary survey work of this kind is that a determination be made at the time the water sample is taken. Results thus obtained can be used to find out whether the saltiness is increasing or decreasing from place to place, and where the next sample should be taken. This advantage is lost if samples must be collected and transported to a laboratory for testing, and in addition, a duplication of time and effort is caused. It was found that Mohr's method for total chlorides by titration with silver nitrate was suitable; the use of a small graduated pipette for measuring the standard solution, and of ordinary test tubes for holding the samples of water, reduced the amount of needed apparatus to such an extent that the required glassware for a day's trip could be placed in a small basket. This paper describes the method that was found satisfactory, gives directions for making up the solutions needed in making the tests, and shows the results obtained by this method with different samples of water.

The design and principles of operation of a direct reading Lucite volumeter for use in the study of respiration, photosynthesis, and gas exchange reactions is described. The detection and compensation device consists of two rigidly coupled pistons driven by a knurled nut; as one piston is moved to compensate for a volume change in the compensation chamber, the displacement is magnified by the larger piston and can be observed as fluid displacement in a graduated pipette. The chambers, pistons, and manometer assembly are exchangeable to permit selection of the relative sensitivity and amplification, in keeping with the temperature control and the absolute magnitude of the volume increments to be detected. With temperature control of ±0.05°C, a thermal stability of 0.2 μl/hr may be achieved and rates of 2.0 μl/hr resolved at 5‐min intervals. Absolute measurements of 0.1 μl may be made. The respirometer is provided with gassing vents. A simple pump may be used for the agitation of the respiration chamber atmosphere to accelerate equilibrium and improve the response time of the instrument. Representative measurements are included.

Several modifications of the roll-tube method have made it simpler for routine use in the isolation and growth of anaerobic bacteria. These include use of a check valve for the production of prereduced anaerobically sterilized media; a Salvarsan tube under oxygen-free gas pressure for the dispensing of molten prereduced anaerobically sterilized agar medium; a Kelly infusion bottle with a graduated pipette side arm (also under gas pressure) for quantitative delivery of fluid prereduced anaerobically sterilized media; and screw-capped prescription bottles for the cultivation of anaerobes. Colonies of Bacteroides melaninogenicus were easily identified and counted by this method. Other anaerobic bacteria have also been cultivated successfully.

A simple method of subsampling a zooplankton sample is described. Statistical analysis of four methods tested showed that bubbling a sample by blowing into it through a graduated pipette and then sucking up the sample gives results comparable to using a swirling flask and a Stempel pipette, to using a swirling flask and a graduated pipette, or bubbling and using a Stempel pipette.