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Studies of pesticide residues on strawberries were conducted in 1957, 1958, 1959, and 1960. It was demonstrated that the berry caps will contain from 28% to 60% of the residue on harvested strawberries. Studies of seven chlorinated hydrocarbons, nine phosphate insecticides, a carbamate insecticide, and four fungicides showed, with only two exceptions, that sprays applied 24 hours before sampling did not leave residues in excess of established tolerances. Thiodan® (6,7,8,9,10,10-hexachloro-l,5,5a,6,9,9a-hexa-hydro-6-9 methano-2,4,3-benzodioxathiepin-3-oxide) applied 24 hours before harvest left residues in excess of the tolerance of 2.0 p.p.m.; also, demeton in more than two spray applications, the last applied within 14 days of harvest, left residues in excess of the 0.75 p.p.m. tolerance. Variation of the spray pressure from 30 to 200 p.s.i. did not have an appreciable effect on residue deposits.

AT THE present time, chronic respiratory disease (CRD) of chickens is generally considered a major source of financial loss to poultrymen. Since the disease was first described (Delaplane and Stuart, 1943) it has become enzootic in every poultry producing area in Canada and the United States. In view of its economic importance and widespread distribution it is evident that measures must be taken either to eradicate or control this disease. Only recently was sufficient information regarding the etiology and mode of transmission obtained to make suggestions for the control of CRD feasible. It is the purpose of this paper to present the data which enables one to propose a plan for the control of CRD. PART 1 Review of Pertinent Facts Incidence. Exact data concerning the incidence of the disease in the United States is not available, but all information points to an extremely high attack rate, especially in areas …

The effects of soil insecticides on newly set Tennessee Beauty strawberries were tested. The results of two-years' work indicated that under conditions of low infestation of the soil-insect complex the treatments generally increased runner length and number of runners. Dieldrin and beptachlor were outstanding. Tests to control tetranychid mites showed that demeton and phorate maintained good control. Thiodan® (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6, 9-methano-2,4,8-benzodioxathiepin-3-oxide) was outstanding for control of the meadow spittlebug philaenus spumarius (L.)) in all tests. There is a possibility that Thiodan may have a detrimental effect on harvest yield of Pocahontas strawberries if it is applied at an early stage of growth. Dyrene® (2,4-dichloro-6-o-chloroanilino- s -triazine), thiram, and captan were effective in control of fruit rots, Botrytis spp. Dodine and Dyrene showed slight phytotoxic effects on foliage injured by mite feeding.

The occurrence of residues of chlorinated hydrocarbon insecticides in animal tissue has been well established in the literature. Thomas et al (I); Fahey and Brindley, (2); Entomology Research Division (3) are three authors who reported the contamination of beef tissues resulting from the feeding of treated forage or permitting livestock to forage on pesticide treated crops. Davich et al (4), reported the occurrence of insecticide residues in swine tissues taken from animals permitted to feed on clover pasture treated with insecticides. Street (5), reported the reduction of dieldrin storage in tissue of rats treated with DDT. Cook and Wilson (6), Wilson and Cook (7), and Cook (8), have shown that dieldrin is constantly being recycled from the blood of cattle to the gastro-intestina l tract, that phenobarbital increases levels of many liver microsoma! detoxifying enzymes, and that charcoal can be utilized as an antidote for dieldrin poisoning in ruminants. Since swine are monogastric animals rather than ruminants and under farm conditions are under a fat accumulation regime rather than a maintenance or loss diet as are milking cattle, doubts arose as to the possibility of utilizing this technique in eliminating dieldrin residues in swine. Preliminary experiments showed that feeder pigs permitted to forage in stover grown on aldrin or heptachlor treated soil may accumulate up to 0.I ppm of dieldrin or heptachlor epoxide. The purpose of this study was to determine whether phenobarbital and charcoal would reduce the storage of dieldrin in the fatty tissue of swine.

Studies were conducted on aldrin and dieldrin residue in soil, water, and crawfish ( Procambarus clarrkii (Girard)) from rice paddies. Samples of a Midland silt loam soil taken on the drill row from plots planted with rice seed (100 pounds per acre) treated with 0.25 pounds aldrin per 100 pounds of seed showed residues of both aldrin dieldrin. Samples taken 1 month after planting had of aldrin in samples taken on the drill row and 2.5 inches from it, but none in samples taken 5 inches from the drill row. At later sampling times no difference noted in aldrin residue at either the 2.5 or the 5 inches sites in check or treated plots. A preexisting dieldrin residue of 300–500 parts per billion (ppb) was found in all plots. No measurable difference in dieldrin levels was found at any site caused by conversion of aldrin to residues decreased at slower rates under these flooded conditions than have been reported for soils exposed to air. Pesticide residues in water from paddies planted with rice seed (100 pounds per acre) treated with aldrin at rates of 0.25 and 0.5 pounds per 100 pounds of seed showed a positive correlation with treatment rate in drill planted but not with water-planted seed. Dieldrin residues dues averaged 0.18 ppb for water-planted rice and 0.28 ppb for drill-planted rice. The dieldrin residues are attributed to a 1.1 ppb aldrin and 850 ppb dieldrin residue present in soils prior to planting. Crawfish reared in paddies planted with treated or non-treated seed and on soil containing up to 200 ppb aldrin and 500 ppb dieldrin were found to contain residues of aldrin, dieldrin, and DDE (I, 1-dichloro-2,2-bis ( P -chlorophenyl) ethylene).

Procedures are described for growth of large single crystals of TiO x, (1.501 ⩽ x ⩽ 1.512) that are reasonably free of cationic impurities and of C and N . Data concerning the stoichiometry and the segregation of impurities during crystal growth are presented. The electrical properties of doped and pure single crystal materials are briefly described.

Surface acoustic wave properties of fresnoite have been calculated from bulk material parameters and have been measured along several orientations on samples cut from Czochralski‐grown crystals. Favorable properties are measured for the z‐cut x‐propagating wave: the coupling coefficient k2 is 0.016±0.003, the velocity is 2678 m/sec, and the temperature coefficient of delay is 51×10−6/ °C. These values, as well as those measured for the much lower coupling x‐z and x‐y surface waves, are in agreement with calculations. The calculations also predict that, for surface waves propagating in the x direction on a surface whose normal is at 45° to z and y axes, the coupling coefficient is 10% higher than calculated for the above z‐x case.

The optical absorption coefficient of Ti:Al2O3 samples at 490 nm for the π polarization (E∥c) is found to be proportional to the concentration of Ti3+ ions, as determined by measurement of the paramagnetic moment as a function of temperature and magnetic field. The experimental data yield the value σ=(9.3±1.0)×10−20 cm2 for the absorption cross section of Ti3+, the active ion in the tunable Ti:Al2O3 laser, at the peak of the laser pump band.

ALTHOUGH chronic respiratory disease (CRD) in chickens and turkeys has been described on many occasions, little attention has been paid to a similar condition occurring in ducks. Dougherty and Fabricant (1953) have shown that CRD “agents” isolated from chickens or turkeys will not cause CRD in ducks and furthermore, that the reported causative agent of “New Duck Disease,” Pfeifferella antipestifer will not cause CRD in chickens. This preliminary report describes an outbreak of a chronic respiratory disease in ducks from which two different agents were isolated. The outbreak occurred on a commercial duck farm in Ontario consisting of 2000 breeders and 10,000 young ducks of various ages. The disease was first noticed in a group of 2 week old ducklings and was characterized by depression, sneezing and some head shaking in the majority of birds. Approximately 2–3% of the affected birds were suffering from sore eyes similar to that …

Field studied of supractice® ( O, O -dimethyl phosphoro-dithioate S -ester with 4-(mercaptomethyl)-2-methoxy∆3-1,3,4-thaiadiazolin-5-one) and carbofuran residence in alfalfa showed that Supracide persisited on green alfalfa for 21 days after treatment. Carbofuran residues were not found 14 days after treatment. Dechydration of alfalfa reduced the Supracide residue by 50–60% and the carbofuran residues by 65%.

The term “air sac” infection has become associated with an exudative process occurring in the abdominal and thoracic air sacs of birds with chronic respiratory disease (CRD). It is this aspect of CRD infection which has been of the greatest concern to the commercial grower since it is the mortality and morbidity accompanying “air sac” manifestation that is of primary importance. “Air sac” infection can, however, be observed in a number of other diseases, such as infectious bronchitis, cholera, paratyphoid and Newcastle disease. The typical appearance of birds with “air sac” infection has been described by Wasserman et al. (1952), who suggested that the terms CRD and “air sac” infection are not synonymous since the latter is caused by a bacterial infection. Luginbuhl et al. (1954) observed that bacteria and fungi play a major complicating role in the pathogenesis of poultry respiratory diseases. This present paper reports briefly on the …

Commercial fields of peppermint and spearmint were sprayed with DDT. DDT residues of 4.21 ppm in hay and 1.54 ppm in oil were found in spearmint sprayed at 1 pound per acre 24 days prior to cutting. On peppermint, 1 pound per acre 34 days prior to cutting resulted in DDT residues of 0.95 ppm in hay and 4.86 ppm in oil. To obtain data to evaluate proposed tolerance levels, exaggerated spraying conditions were employed. These included increasing dosage to 2 pounds per acre and/or an application very close to cutting. These conditions resulted in higher residues in hay and oil. However, no correlation between DDT residues in hay and oil could be found. A rapid method of determining DDT in mint oil is described.

A resistance heated crystal puller has been used to grow crystals of NbO, Ti2O3, and Al2O3, which have melting points of 1945, 2000, and 2050°C, respectively. The puller incorporates a modified version of a tantalum tube furnace described previously, which is capable of operating in oxidizing, neutral, and reducing atmospheres up to 2400°C. The seed holder is water‐cooled.

The demonstration1 of the wavelength-tunable Ti:Al2O3 laser has led to renewed interest in the growth of sapphire crystals doped with Ti3+ ions, which are responsible for the laser action. Laser performance has generally been limited by a parasitic optical absorption band of unknown origin that is present in the laser output wavelength region.

Poly vinyl chloride (PVC) has been one of the most widely used materials in the plastics industry for the last three decades. Consumption in the U. S. alone exceeded five billion pounds in 1980 and is expected to continue to grow. The extent of its usage results from the wide range of properties attainable with PVC, its low cost, and the relatively low energy requirements for its production. The achievement of a broad range of properties based on a common material arises from the almost limitless number of compounds which can be formulated from PVC through the use of a wide variety of additives.

A seeded vertical gradient-freeze technique has been used to grow Ti:Al203 single crystals with low residual infrared absorption from charges containing between 0.15 and 1.0 wt.% Ti203 in tungsten crucibles. In laser experiments on samples cut from these crystals, room-temperature cw operation has been achieved for rods containing between 0.024 and 0.099 wt.% Ti203.

A seeded vertical gradient-freeze technique has been used to grow laser-quality Ti:Al2O3 single crystals with low residual infrared absorption from charges containing between 0.15 and 1.0 wt.% Ti2O3 in tungsten crucibles.

This paper reports on the room-temperature cw operation of several Ti:Al2O3 laser rods pumped by an Ar-ion laser. For one rod, a threshold of 2.3 W, maximum output of 1.6 W, and slope power efficiency of 19% were obtained at 770 nm, and continuous tuning was observed from 693 to 948 nm.

In this paper we report the first room-temperature cw operation of a Ti:Al2O3 laser. Moulton1 has previously reported cw operation at liquid nitrogen temperature, but at room temperature he obtained only quasi-cw operation by chopping the pump beam at a 16% duty cycle. Using an Ar-ion laser operating in all the blue-green lines as the pump source, maximum power of 1.6 W has been obtained at 770 nm, near the peak of the gain profile, and continuously tunable cw operation Ti:Al2O3 has been achieved from 693 to 948 nm.

IN the chronic respiratory disease syndrome of chickens and ducks, both a virus and pleuropneumonia-like organisms have been etiologically implicated1. Serological studies on infectious sinusitis of turkeys, utilizing a haemagglutination-inhibition test, indicated that there is a relationship between presence of antibodies against the pleuropneumonia-like organisms and a clinical sinusitis2. However, in some birds, infection with the pleuropneumonia-like organisms did not result in development of a sinusitis. Observations on field-outbreaks of chronic respiratory disease and their relation to the onset and severity of sinusitis in turkey flocks seemed to indicate that the pleuropneumonia-like organisms did not serve to define the etiology of these syndromes. This became apparent in two outbreaks when it was demonstrated that a large percentage of the birds were serologically positive to the pleuropneumonia-like organisms prior to the onset of respiratory symptoms, and furthermore that sinusitis was observed in only 2–5 per cent of the birds. Within two weeks after the onset of the respiratory symptoms, 40 per cent of the birds in one flock and 60 per cent of the birds in the other flock developed sinusitis.

Hogs pasturing on corn stover in insecticidally treated fields accumulated measurable residues of dieldrin and heptachlor epoxide. Hogs weighing between 40 and 60 pounds were placed on these treated fields for varying periods of time. Residues of heptachlor epoxide and dieldrin accumulated in the fat to levels of from 0.032 to 0.071 ppm. of heptachlor epoxide and from 0.080 to 0.141 ppm. of dieldrin. Removal of the animals to concrete slabs for further fattening for varying periods of time reduced but did not eliminate these residues.