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Summary form only given.Analog applications of VCSELs require highly linear wideband operation, minimal intermodulation distortion, and high dynamic range. The maximum spur-free dynamic range (SFDR) obtained for a VCSEL is 104.3 dB Hz/sup 2/3/ at 102 MHz; error-free analog transmission over 3 km of fiber has been demonstrated at 1 GHz. This work suggests that, with future design improvements, VCSELs may be able to compete with DFB lasers for analog applications. The device used in this study is a VCSEL with an independently biased, voltage-controlled, intracavity absorber.

Labeled L-N-arachidonylphosphatidylethanolamine (L-N-arachidonyl PE), a likely precursor of N-arachidonylethanolamine (anandamide), as well as its D-isomer, were synthesized using [14C]arachidonic acid. Anandamide was formed by incubating L-N-arachidonyl PE and rat brain membrane with phenylmethylsulfonyl fluoride (PMSF), an inhibitor of anandamide amidohydrolase. Formation of anandamide from L-N-arachidonyl PE was inhibited by p-chloromercuriphenylsulfonic acid (p-CMPS), sulfhydryl reagent, and heat inactivate pre-treatment. D-N-Arachidonyl PE, an unnatural analog for N-arachidonyl PE, did not form anandamide.

Summary form only given. We report the first single mode independently addressable oxide confined GaAs-AlGaAs QW DBR VCSEL laser array. The 4/spl times/8 VCSEL array has very uniform electrical, modal and geometrical characteristics that make it ideal for 2D array applications.

Mid-infrared laser diodes are important sources for laser radar systems, molecular spectroscopy, and remote sensing of pollution and gases. InGaSbAs/GaAlSbAs lasers emitting at 2 μm are explored in detail since first room-temperature (RT) lasers [1-3] were demonstrated. However, a breakthrough in 3-4 μm lasers was made only recently [4-6]. Long wavelength lasers exhibit low characteristic temperature (T0 ≤ 30 K [6]), preventing them from operation at RT. One of the possible reasons of high threshold current at RT is Auger-recombination, which is proportional to cube of carrier density. Therefore, for long-wavelength lasers, it is especially important to decrease the carrier density at threshold.

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In order to confirm the presence of a phosphoenolpyruvate (PEP)-dependent sugar-phosphotransferase system (PTS) in the mollicute Acholeplasma florum we studied the ability of cell free extracts of this organism to phosphorylate glucose and/or fructose in the presence of PEP. We also cloned and sequenced a DNA fragment coding for a putative polypeptide showing significant similarity with the enzyme II of the beta-glucoside PTS of Escherichia coli. Taken together, these results show that A florum possesses a fructose-PTS, but not a glucose-PTS, and that the amino acid sequence deduced from the DNA fragment is related to beta-glucoside and sucrose enzymes II of PTS from various bacteria.

Microdisplay device is well known as high resolution imagers. In this study, we propose that using microdisplay as the vision test chart imagers. The measurements, such as vision acuity and contrast sensitivity, can be by using this kind of device.

Pierce's disease, caused by the bacterium Xylella fastidiosa Wells et al., is widespread among muscadine grapes (Vitus rotundifolia Michx). To determine whether shoot-tip culture would be effective in eliminating X. fastidiosa, shoot tips of infected grape plants were cultured on Murashige and Skoog medium amended with 9 μm benzyladenine. Shoots and callus that developed tested negative for the presence of X. fastidiosa. Shoot-tip culture appears to be a promising method of obtaining muscadine grape plants free of Pierce's disease. Chemical name used: 6-benzylaminopurine (benzyladenine).

An electrostatically controlled cantilever apparatus for continuous tuning of the resonance wavelength of a Fabry-Perot cavity is disclosed. A resonant cavity is formed between two distributed Bragg reflector (DBR) mirrors each composed of multiple DBR layers. One such layer is replaced with a layer which has been fully oxidized except for a small aperture. This layer provides both optical and current confinement which allows for low threshold currents and high output power.

Screening of muscadine grape (Vitis rotundifolia) plants in vineyards has revealed that many plants carry Xylella fastidiosa; under suitable conditions, this bacterium causes Pierce's disease which can result in considerable loss. To determine whether propagation of muscadine through shoot tips would eliminate X. fastidiosa, plants were injected with this bacterium. After demonstrating infection, shoot tips were collected and cultured. according to the technique of Barlass and Skene (1978). Plants which were regenerated were found to be free of the bacterium. To determine whether this shoot-tip culture technique would be effective for propagation of a diverse group of muscadines, 19 cultivars were tested. Three of the cultivars failed to produce any plants, and several others reproduced at a low rate of efficiency. In an attempt to improve the rate of regeneration, several modifications to the technique were tested. For most cultivars, better initiation occurred on liquid medium, more shoots were produced with BA than with 2iP, and the addition of adenine sulfate and sodium phosphate improved the regeneration frequency.

1. Brain microsome phospholipids and their acyl groups, from temperature and oxygen acclimated goldfish, were investigated. 2. At the lower acclimation temperature (5C) the proportion of ethanolamine- to choline-glycerophosphatides (GPE/GPC) was increased, and the proportion of phosphatidal ethanolamine value decreased. 3. A rise in then-6/n-3 fatty acyl group also occurred in cold acclimation. 4. Irrespective of acclimation temperature, 25°C or 5°C, a partial replacement of GPC by GPE occurred when the concentration of oxygen was increased; conversely the GPE/GPC ratio decreased at the hypoxic level. The plasmalogen GPE content increased as the oxygen concentration was raised. 5. A rise in the n-6/n-3 ratio, for ethanolamine glycerophosphatides and phosphatidyl choline, occured when the oxygen concentration was increased (hypoxia to hyperoxia). 6. It is concluded that the lipid alterations associated with thermal acclimation are, in part, attributable to the concomitant change in oxygen concentration.

1. 1.|The phospholipid composition of purified outer and inner brain mitochondrial membranes, from temperature acclimated goldfish, was investigated. 2. 2.|For outer membrane, the phospholipid profile shows the choline-containing lipids (GPC and SM) as the predominant components. When temperature was varied (30–5°C), the proportion of only one phospholipid (PS) was altered significantly. 3. 3.|The level of ethanolamine- and choline-glycerophospholipid, the major phospholipids of the inner membrane, increased at the lower acclimation temperature. Also, the relative amounts of other phospholipids (PS, SM, PA and CL) showed a significant decrease at 5°C. 4. 4.|It is concluded that the outer and inner membranes of mitochondria differ in their response to maintain fluidity at temperature extremes.

Isolation of xylem-limited bacteria (XLB) on CS20 agar medium was used to assess bacterial survival in plum trees. Thirty to forty twigs were randomly sampled monthly from each of the three trees with plum leaf scald from October 1982 to October 1984. From December 1983 to May 1984, 16-24 roots were also sampled from three other trees and plated on CS20BN agar medium. Sap obtained by squeezing each surface-sterilized twig or root with pliers was immediately placed on the surface of CS20 or CS20BN agar. Plates were incubated at 30C and examined weekly with a microscope (50×) for bacterial colonies. Bacteria were isolated each month, except May 1983 and April 1984, from cultivar “Santa Rosa”; each month, except May 1983, February and April 1984, from cultivar “Burbank”; each month from July to December 1983 and August to October 1984 from cultivar “Ozark Premier”. XLB were isolated from root samples of each tree from November 1983 through May 1984. Results demonstrate that XLB can survive through winter at Byron, Georgia, and suggest that the XLB may be transmitted to healthy trees anytime vectors are present.

Oxytetracycline (OTC) suppressed leaf scald symptoms in plum following trunk injection. Tools required were a cordless drill, a 28/163cm drill bit, a hammer and J.J. Mauget's OTC capsules. Two injection schedules, one in late April or early May and the other in mid October, were selected for the best effect. Two capsules, each containing 0.16g of OTC in 4ml solution were injected into each tree each time and two capsules of carrier solution were injected in control trees. After the first, third, and fifth injection in April, 1984, May, 1985 and May, 1986, respectively, OTC caused 61.5-100%, 73.3-100%, and 76.9-100% symptoms suppression recorded in August, 1984, 1985, and 1986, respectively. In May, 1985, after the second injection was administered in October, 1984, treated trees showed much less twig dieback than control trees.

Electroencephalographic patterns observed during increasing depth anesthesia with thiopental sodium-ether, with ketamine hydrochloride-ether and with pentobarbital sodium were correlated with concentration of anesthetic agents in the blood. Analysis of electroencephalogram was made by histogram method.The results are as follows:1) Before anesthesia phase; Beta band of 20-25 Hz waves were shown 60-70% following alpha band was 30%.2) Induction phase; Delta band and theta band were increasing about 40% in place of beta band, but case of ketamine hydrochloride intervenous were increased beta band.3) Maintenance phase; 20-30% ether gas inhalation 5 minutes, a few beta band increased when this stage ether concentration in blood was about 60 mg/dl. Ether concentration in blood was over 70 mg/dl increasing delta band and theta band appearance ratio.4) Ether inhalation 30 minutes stage; Ether concentration in blood of 110 mg/dl when it was delta band only appearance ratio over about 50%.It was suggested that this method of analysis is adaptable to the quantitative study of contribution of each anesthetic agents when used simultaneously, provided that a significant change in EEG patterns and frequency band (delta, theta, alpha and beta waves bands), subject to classification, is produced by the agents considered.From the results of the present work, it was concluded that the changes EEG patterns were closely related to the depth of anesthesia and pharmacokinetics in the dog anesthetized with ether.

Ascospores (10 5 /ml) of Neosartorya fischeri var. glaber (FRR 1833) harvested from grape juice agar after 11 d of incubation at 30°C were inactivated by treatment at 82° for 60 min; 25-day-old ascospores survived this heat treatment. To determine if differences in ultrastructure and chemical composition might be related to differences in heat-resistance, ultrastructure as well as protein, lipid, sugar and polyol contents of 11-day-old (heatsensitive) and 25-day-old (heat resistant) ascospores were compared. SEM revealed little difference in external appearance, whereas TEM revealed some internal differences between 11- and 25-day-old ascospores, particularly in the region of germ-tube initiation. Significant qualitative differences in protein content between heat-sensitive and heat-resistant ascospores were observed. The lipid and fatty acid compositions of the two types of ascospore were similar. Heat-resistant ascospores contained higher levels of glycerol, mannitol and trehalose than heat-sensitive ascospores, suggesting that the lowering of internal water activity or membrane stabilization may partially account for increased heat resistance.

1. 1.|The mitochondrial outer membrane from goldfish contains on average approximately six times more phosholipid and eleven times more cholesterol than the inner membrane. 2. 2.|When acclimation temperature was lowered the amount of cholesterol to protein significantly decreased in the outer membrane, but remained unchanged in the inner membrane. 3. 3.|Although the amount of total phosphorus to cholesterol was not temperature dependent for inner membrane, it was found to be negatively correlated ( P 4. 4.|It is concluded that fluidity in the mitochondrial outer membrane is regulated by cholesterol whereas in the inner membrane, which contain very low quantities of this lipid, cholesterol has little or no influence on the fluidity properties.

Summary The effects of high temperature stress on tomatoes ( Lycopersicon esculentum L. cv. «Flora-Dade») were studied at both the tissue and cellular levels. Ethylene-treated, mature-green fruit were stored at 37 °C, 55 % RH for 3 and 7 days, then ripened at 21 °C, 55 % RH. A control group was ripened at 21 °C, 55 RH continuously. Effects were monitored for a total period of 17 days. Tissue softening, red color development, and climacteric production of ethylene were delayed by high temperature. The rate of respiration and the respiratory control ratio were higher in mitochondria isolated from the stressed fruit than from the control. ATPase activity of mitochondria in the presence of Ca 2+ was affected by heat treatment within 3 days of storage at 37 °C. No effect due to high temperature storage was observed using electron microscopy.