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The protocol decribes the procedure and results of our attempts to transform several species of marine protists by nucleofection.

In this protocol we publish the maps and sequences of specific plasmids designed for the transformation ofBigelowiella natans, Pyramimonas parkeae, Eutreptiella gymnastica, Chromera velia and Pseudonitzchia delicatissima. All these plasmids contain gene for firefly lucipherase as a reporter, some of them contain PAC (puromycin) or G418 (neomycin) resistance gene. All genes are flanked by organism specific up- and downstream gene regions extracted from genomic and transcriptomic data. It should be noted that we were not successful in any transformation by these plasmids, but it does not mean that the problem is in the plasmids. All plasmids are available upon request. The plasmid maps and sequences can be downloaded as a word file from More/Material section of this protocol.

An association between nasal cancer and other health effects and occupations involving exposure to wood dust has been clearly established in the literature. Therefore, it was deemed necessary to conduct research to develop new improved methods to control this dust. This article reports on the research that has been conducted by investigations at the National Institute for Occupational Safety and Health (NIOSH) on rotational hand-held Sanders. A new control system was developed to be used in conjunction with existing controls that are used on these sanders, which consist of an aspirator and a perforated sanding disc pad. The new control system includes additional suction applied to the sander body and a specially designed, slotted sanding disc pad to relieve the increased pressing of the sander to the sanded surface imposed by the increased vacuum. The newly designed sanding disc pad also captures wood dust from the sanded surface directly at the pad periphery. In the laboratory, the new control s...

Association between nasal cancer and other health effects and occupations involving exposure to wood dust has been clearly established in the literature. This article reports on the research that has been conducted by scientists at the National Institute for Occupational Safety and Health (NIOSH) to reduce wood dust emissions from large-diameter disc sanders. An air jet stripper system was developed to be used in conjunction with existing local exhaust ventilation to reduce dust emissions. The system consists of a set of jets located inside the local exhaust hood. The jets are supplied with pressurized air. The control system, combined with currently existing controls, reduced wood dust emissions (area and breathing zone) by an average of 60 percent. Laboratory results were confirmed by field tests conducted at a wood furniture manufacturing plant. The control system does not interfere with the worker's activity, requires minimum maintenance, and is inexpensive to install and operate. This system...

An association between nasal cancer and occupations involving exposure to wood dust has been clearly established in the literature. Therefore, it was deemed necessary to conduct research to develop new and improved methods for controlling this dust. This article reports on the research that has been conducted by scientists at the National Institute for Occupational Safety and Health (NIOSH) on automated routers. A computer-controlled jet stripper system was developed to reduce the wood dust emissions from automated, multidirectional routers. The system consists of a set of 24 jets, combined into 8 operational units which are uniformly located around the entire inside periphery of the brush holder above the worktable. The jets are supplied with pressurized air and are activated by pneumatic valves as needed. The system is also effective in controlling the wood dust from conventional, one-dimensional routers, especially when routing is performed under the upper surface of the workpiece and provided...

An air curtain-exhaust ventilation system was investigated as an effective control for formaldehyde exposures from a wood panel veneering press. The investigated system consisted of two air curtain manifolds located vertically at both press sides and an exhaust located at the press end opposite to the manifolds. This air curtain creates an air barrier between the worker and the press from where the formaldehyde is emitted. The air curtain stream is shifted toward the press wall by the exhaust, creating a narrow air zone between the worker and the press wall which minimizes the air streamsapos; interference with the operator. The performance of the air curtain system was evaluated using sulfur hexafluoride as a tracer gas which simulated formaldehyde emission. The data indicate that a greater than 94 percent reduction in exposure levels can be achieved and that the ventilation system studied can be applied effectively to a multiple opening press.

The purpose of this research was to investigate the air curtain-exhaust ventilation system as an effective control at a rubber milling process. The investigated system consisted of an air curtain and an enclosure added to the existing control. The air curtain was located between the contaminant source and the mill operator to create an air barrier between the operator and the emission source. The enclosure covered the space between the exhaust hood and the mill's back side to eliminate contaminant emission at this space and to increase hood face velocity at the operator side. Laboratory and field test data indicate that a significant reduction in emissions was achieved when this system was operating, even when the existing hood exhaust airflow rate was reduced by 33%.

One of the most commonly used controls of harmful industrial contaminants is a local exhaust hood. The efficiency of this system is defined as the ratio of air contaminant quantity captured by the system per unit time to the total contaminant quantity produced by the process per unit time. A tracer gas technique, using sulfur hexafluoride (SF6), has been developed for the efficiency estimation of hoods controlling gaseous or vaporous contaminants. To extend the applicability of this method to hoods controlling particulate contaminants, a relationship between the hood particle capture efficiency and the hood efficiency determined by the tracer gas technique was studied. A particulate tracer was used for the hood efficiency and the data were compared with those obtained by the SF6 technique. Both tracers were discharged under the same conditions. Based on a statistical data analysis, described in detail in this paper, a mathematical relationship between the efficiency obtained by both particulate and SF6 wa...

An auxiliary ventilation system has been developed to reduce the wood dust emission from horizontal belt sanders. This system consists of two devices: a hood and a jet stripper. The hood is a narrow low-volume, high-velocity slot hood located between a belt surface and a worktable; the push device is a jet stripper located inside a driven pulley hood opposite the operator site. In combination with a standard sander hood, both devices significantly reduced the wood dust emission into the workroom. Laboratory data were confirmed by field tests conducted at an oscillating edge belt sander at a wood furniture manufacturing plant. These devices work independently of each other and do not interfere with the operator's sanding activity. They do not require special maintenance and are economically feasible.

A tracer gas technique using sulfur hexafluoride (SF6) was developed for the evaluation of industrial exhaust hood efficiency. In addition to other parameters, accuracy of this method depends on proper location of the sampling probe. The sampling probe should be located in the duct at a minimum distance from the investigated hood where the SF6 is dispersed uniformly across the duct cross section. To determine the minimum sampling distance, the SF6 dispersion in the duct in fully developed turbulent flow was studied at four duct configurations frequently found in industry: straight duct, straight duct-side branch, straight duct-one elbow, and straight duct-two elbows combinations. Based on the established SF6 dispersion factor, the minimum sampling distances were determined as follows: for straight duct, at least 50 duct diameters; for straight duct-side branch combination, at least 25 duct diameters; for straight duct-one elbow combination, 7 duct diameters; and for straight duct-two elbow combination, 4 duct diameters. Sampling at (or beyond) these distances minimizes the error caused by the non-homogeneous dispersion of SF6 in the duct and contributes to the accuracy of the tracer gas technique.

Efficiency of industrial local exhaust ventilation is defined as the ratio of air contaminant quantity captured by the system per unit time to the total contaminant quantity produced by the process per unit time. To date, no direct method exists for this evaluation. This paper describes a tracer gas technique, using sulfur hexafluoride (SF6), which has been developed for the evaluation of local exhaust system efficiency. SF6 was discharged at a known rate into the industrial process generation area. Then, by comparing this quantity to that captured by the exhaust system, as measured in the exhaust duct, hood efficiency is determined. Major advantages of this technique are: The tracer gas technique is able to evaluate directly the hood efficiency. The tracer gas technique is not affected by cross-contamination from nearby industrial processes. The tracer gas technique can be conducted "on site" with minimal interruption of industrial process or interference with workers' duties. The tracer gas, using SF6 is non-toxic. Since SF6 is a gas, this technique may be limited to efficiency evaluation of hoods associated with gases, fumes, vapors, or fine particles.

Experiments using the directed push-pull ventilation technique were conducted on a general type of local exhaust ventilation installation. The exhaust (pull) system consisted of a square hood, while the push system consisted of one or two slot jets or two round jets. The two slot or round jets were located behind and beside a mannequin (the mannequin simulated the worker's position). The one slot jet was located between the smoke source and the mannequin. Under experimental conditions, the push-pull system reduced the amount of smoke in the mannequin's breathing zone even when the exhaust system volume flow rate necessary for capture of the smoke decreased approximately 50%. Generally, no difference between the slot and round jet control performance was found. The experiments showed that the directed push-pull ventilation system can be used effectively to reduce the contaminant emission into a workroom, if the jets are located so that the eddy currents induced by the worker or other obstructions are minimized or eliminated.