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Ventricular sympathetic denervation may occur as a result of myocardial infarction or heart transplantation. The present study examined the time-dependent effects of surgical ventricular sympathectomy on coronary flow and myocardial contractile responses to intracoronary norepinephrine administration in conscious dogs.Adult mongrel dogs (18-26 kg), were either ventricular sympathectomized or served as a sham-operated control. Animals were studied 2, 4, and 8 weeks after surgery. Measurements of left ventricular systolic pressure (LVSP), maximum rate of left ventricular pressure generation (dP/dtmax), maximum negative rate of segmental shortening (-dL/dtmax), heart rate, and mean circumflex flow velocity (CFV) were obtained before and after bolus administration of norepinephrine into the circumflex artery in doses ranging from 0.01 to 0.50 microgram.Intracoronary norepinephrine administration caused significant increases in LVSP, dP/dtmax, -dL/dtmax, heart rate, and CFV. After reaching a peak or maximum response, these variables returned to their respective preinjection values, except for CFV, which exhibited a biphasic response. CFV continued to decline below control levels, indicating a vasoconstrictor response to norepinephrine, before returning back to preinjection levels. With the 0.5-microgram dose of intracoronary norepinephrine, the percent increases in CFV were 124% +/- 25% and 105% +/- 15% (P0.05) at 2 and 4 weeks respectively, compared with the sham-operated controls, which only increased 56% +/- 15%. The response to the 0.5-microgram dose of norepinephrine at 8 weeks (61% +/- 6%) was not significantly different from control. Elevated myocardial contractile responses in the sympathectomized hearts were also evident at 2 and 4 weeks, but not at 8 weeks. The vasoconstrictor response to norepinephrine administration was not significantly different between sympathectomized and sham-operated hearts. Finally, there was no difference in the change in LVSP, dP/dtmax, or heart rate between any of the groups at any of the doses.These results suggest that a supersensitivity to the coronary functional hyperemic response after intracoronary norepinephrine is present in ventricular sympathectomized hearts, but a coronary constrictor supersensitivity does not exist.

The question of whether nuclei are polarized as a result of H–H(D–D) spin‐exchange collisions within the relatively dense gas of a laser‐driven source of polarized hydrogen (deuterium) can be addressed directly by measuring the nuclear polarization of atoms from the source. The feasibility of using a polarimeter based on the D+T→n+4He reaction to measure the tensor polarization of deuterium in an internal target fed by the laser‐driven source has been tested. The device and the measurements necessary to test the spin‐exchange polarization theory are described.

Polychlorotrifluoroethylene (3.1 oil) is a nonflammable hydraulic fluid composed of chlorotrifluoroethylene (CTFE) oligomers of different carbon chain lengths (C5 to C9), primarily six (trimer) and eight (tetramer) carbons. Four test groups of Fischer 344 rats (16 rats/group) were orally gavaged daily over a 2-week period at doses of 1.25 g/kg with 3.1 oil containing a 55:45 ratio of trimer and tetramer (3.1 oil-C6:C8), 3.1 oil composed of 95% trimer (3.1 oil-C6), pure tetramer, and pure trimer. Four rats per treatment group were terminated after 1, 3, 7, and 14 doses. Rats dosed with either 3.1 oil-C6:C8 or pure tetramer demonstrated significant weight losses, increased liver weights, increased rates of liver fatty acid beta-oxidation, pronounced hepatomegaly and altered hepatocellular architecture, and elevated serum liver-associated enzymes. Rats dosed with either 3.1 oil-C6 or only pure trimer demonstrated significant increase in liver weight and moderate liver histopathologic changes. Compositional analyses of the ratio percentage of trimer to tetramer present in 3.1 oil-C6:C8 (55:45) were found to be altered when measured in the liver (32:68). Differential CTFE oligomer toxicity was indicated by effects on liver, body weight, and peroxisomal beta-oxidation and may allow for less toxic formulations of 3.1 oil to be generated by reducing or eliminating the tetramer component.

Previous work has shown an increase in sympathetic stimulation of the heart during chemical or mechanical irritation of visceral organs, but the involvement of the coronary circulation in such reflexes is not clear. In five preliminary experiments in anesthetized dogs, esophageal distention produced a sympathetic stimulation of the heart, as evidenced by an increase in heart rate, which was abolished by non-selective beta-adrenergic and muscarinic blockades. On the basis of these preliminary data, we further examined a sympathetic coronary constriction during acute esophageal distension in which any direct adrenergic coronary constriction was unmasked by muscarinic blockade with atropine (100 micrograms/kg, i.v.), and non-selective beta-adrenergic blockade with propranolol (1 mg/kg, i.v.). In seven dogs anesthetized with alpha-chloralose in an open-chest procedure, the esophagus was rapidly distended to a pressure of 36 +/- 2 mm Hg, which was not significantly different from the distending pressure used in the preliminary experiments. During esophageal distention, the mean circumflex blood flow decreased to 77 +/- 10% (SEM) of the predistention value. This decrease was statistically significant (p less than 0.05). There was no change in left ventricular pressure, mean arterial pressure dP/dtmax, or heart rate. Intracoronary administration of the nonselective alpha-adrenergic antagonist phentolamine completely abolished the reduction in mean circumflex coronary blood flow caused by esophageal distention in the presence of beta-adrenergic and muscarinic blockades. These results demonstrate a direct sympathetic coronary vasoconstriction elicited by esophageal distention. This vasoconstriction was due to activation of coronary alpha-adrenergic receptors.

The present study was designed to determine whether 12 wk of daily exercise alter autonomic neural control of the heart during baroreflex stimulation in healthy dogs. We studied 16 untrained and 12 endurance-trained anesthetized dogs which were instrumented to measure arterial blood pressure (AP), carotid sinus baroreceptor pressure (CBP), electrocardiogram (ECG), heart rate (HR), and R-R interval (RR). The arterial baroreflex was studied during hypertension caused by i.v. bolus infusion of phenylephrine, hypotension caused by i.v. bolus infusion of nitroprusside, and bilateral carotid occlusion (BCO) in which carotid sinus pressure was reduced to 41 +/- 2 mm Hg (mean +/- SEM). Arterial baroreflex sensitivity, which was assessed by determining the change in heart interval (i.e., change in RR) per unit change in systolic AP (delta RR/delta AP), was significantly lower during the hypertensive challenge in the trained dogs compared to the untrained dogs (2.2 +/- 0.3 vs 6.8 +/- 1.5 ms.mm Hg-1, respectively). Similarly, the delta RR/delta AP was substantially lower during the hypotensive challenge in trained dogs vs the untrained dogs (1.2 +/- 0.3 vs 1.8 +/- 0.4 ms.mm Hg-1, respectively). In addition, the HR response to the BCO was significantly less in trained dogs (22 +/- 2 bpm) vs untrained dogs (32 +/- 5 bpm). The open-loop gain (Go), which was used to quantitate the effectiveness of the carotid baroreflex to increase mean systemic AP during BCO, was similar in both untrained and trained dogs (2.9 +/- 0.6 and 2.4 +/- 0.5, respectively). These data indicate that, while endurance training significantly reduces the HR component of the arterial baroreflex, the arterial pressure response apparently is not altered.

This paper reviews work primarily from our laboratories, examining an alpha 1-adrenergic receptor-mediated coronary constriction during exercise and myocardial ischemia in dogs. It was demonstrated that in the quiescent conscious dog, the coronary circulation is devoid of an alpha 1-coronary constriction. Furthermore, it was shown by the intracoronary injection of selective agonists that both alpha 1- and alpha 2-receptor subtypes are present in coronary vessels. However, during exercise or ischemia only the selective alpha 1-antagonist prazosin caused an increase in coronary inflow, indicating that only alpha 1-receptors were activated. During both conditions, the increase in flow caused by alpha 1-blockade was associated with an increased contractile function in subendocardium. In experiments on anesthetized dogs, it was shown that prazosin caused an equal increase in perfusion of subepicardial and subendocardial layers during stellate ganglion stimulation. However, contractile function was increased only in subendocardium. It was proposed that only in deeper muscle layers does an alpha 1-coronary constriction impose a flow-limitation on contractile function. Finally, recent results indicate that myocardial ischemia, produced either by partial coronary stenosis or by maintenance of coronary inflow at the resting level during exercise, may initiate a vicious cycle with a further increase in alpha 1-adrenergic coronary constriction. Abolition of this positive feedback mechanism may partially explain the anti-infarction effects of chronic ventricular sympathectomy, as previously observed in our laboratories.

Inputs and losses from Giant Parramatta grass [GPG, Sporobolus indicus (L.) R. Br. var. major (Buse) Baaijens] soil seed banks were quantified on the North Coast of New South Wales. Monthly potential seed production and actual seed fall was estimated at Valla during 1991-92. Total potential production was >668 000 seeds/m2 for the season, while seed fall was >146000 seeds/m2. Seed fall >10000 seeds/m2.month was recorded from January until May, with further seed falls recorded in June and July. The impact of seed production on seed banks was assessed by estimating seed banks in the seed production quadrats before and after seed fall. Seed banks in 4 of the 6 sites decreased in year 2, although seed numbers at 1 damp site increased markedly. Defoliation from mid-December until February, April or June prevented seed production, reducing seed banks by 34% over 7 months. Seed banks in undefoliated plots increased by 3300 seeds/m2, although seed fall was estimated at >114 000 seeds/m2. Emergence of GPG seedlings from artificially established and naturally occurring, persistent seed banks was recorded for 3 years from bare and vegetated treatment plots. Sown seeds showed high levels of innate dormancy and only 4% of seeds emerged when sown immediately after collection. Longer storage of seeds after collection resulted in more seedlings emerging. Estimates of persistent seed banks ranged from 1650 to about 21260 seeds/m2. Most seedlings emerged in spring or autumn and this was correlated with rainfall but not with ambient temperatures. Rates of seed bank decline in both bare and vegetated treatment plots was estimated by fitting exponential decay curves to seed bank estimates. Assuming no further seed inputs, it was estimated that it would take about 3 and 5 years, respectively, for seed banks to decline to 150 seeds/m2 in bare and vegetated treatments.

Five new species of Cyclanthera are here described: C. cogniauxii from the Central Cor- dillera of Costa Rica; C. dieterleana from Durango, Mexico; C. dioscoreoides with a disjunct distribution in Mexico, Mexico, and Suchitepequez, Guatemala; C. entata from Chiapas, Mexico; and C. heiseri from Durango, Sinaloa, and Jalisco in Mexico. Cyclanthera Schrader, a distinctive genus of New World cucurbits in the tribe Cyclanthereae, can be easily recognized either by its single, unfolded hor- izontal ringlike theca or by its oblique, explosively dehiscent capsular fruits. At dehiscence, the seeds are thrown by a catapult-like placental arm. Similar explosively dehiscent fruits are found in the closely related Elateriopsis Ernst, Hanburia Seemann, Pseudocyclanthera Martinez Crovetto, and Ryti- dostylis Hooker & Arnott. Cyclanthera is a mod- erate-sized genus as far as the Cucurbitaceae is concerned, including 35-40 species of small annual herbaceous vines. Study of collections in the course of preparing a monograph of the genus has brought to light five new species from Mexico, Guatemala, and Costa Rica, which are here described.

3H-Androgens in rat epididymal interstitium have previously been shown to move into the epididymal lumen against a concentration gradient. This is true especially in the caput epididymidis. The present investigation used the technique of in vivo epididymal perifusion and tubule micropuncture to demonstrate that the proluminal movement of 3H-androgens is subject to competitive inhibition (unlabeled testosterone in the perifusion fluid at 10 times and 100 times the concentration of 3H-testosterone significantly reduced proluminal movement of isotope) and is not energy-dependent (1 mM 2,4-dinitrophenol in perifusion fluid did not reduce the proluminal movement of isotope). Additionally, dry-mount autoradiography demonstrated high intraluminal concentrations of isotope relative to interstitial concentrations after caput tubule incubation in 3H-dihydrotestosterone (3H-DHT), and showed that the high intraluminal concentrations of isotope were not dependent on the presence of spermatozoa, i.e. proluminal movement of 3H-androgens was not due to binding to intraluminal spermatozoa. Isolation of caput epididymidal sperm on filters followed by 3H-DHT binding experiments also failed to demonstrate the presence of specific binding of this androgen to spermatozoa. Finally, it was confirmed that electrophoresed epididymal lumen fluid contains a single 3H-DHT binding peak that is at its highest concentration in the caput epididymal fluid. These data are consistent with the conclusion that intraluminal androgen-binding protein is an important factor in transepithelial androgen movement.

The hypothesis that adenosine mediates the coronary vasodilatory response to hypoxia was tested by determining if intracoronary infusion of the adenosine degrading enzyme, adenosine deaminase (ADA), would attenuate this response. Efficacy of ADA was also evaluated by examining its effect on the coronary responses to exogenous adenosine and to 20-s myocardial ischemia. Experiments were conducted in 14 anesthetized, open-chest dogs ventilated 3-5 min with 3% O2-5% CO2-92% N2 to induce systemic hypoxia. Under control, pre-ADA conditions, hypoxia (arterial PO2 19 +/- 2 mmHg) caused left anterior descending (LAD) coronary blood flow to increase from 100 +/- 12 to 382 +/- 47 ml X min-1 X 100 g-1 (+282%). After infusion of ADA (5 U X kg-1 X min-1 for 8-10 min) into the LAD, equally severe hypoxia (arterial PO2 18 +/- 3 mmHg) caused a significantly smaller increase in LAD flow, 79 +/- 9 to 234 +/- 41 ml X min-1 X 100 g-1 (+195%). Oxygen consumption in the LAD perfusion field was unchanged by hypoxia before ADA but fell significantly during hypoxia after ADA. ADA also attenuated significantly the coronary vasodilatory response to exogenous adenosine and to 20-s ischemia. The results of this investigation demonstrate a significant role of adenosine in the coronary vasodilatory response to systemic hypoxia.

It is important to be able to nondestructively characterize (‘‘screen’’) the electrical properties of those areas of HgCdTe epitaxial material that will later be made into devices. This paper compares several noncontact techniques for measuring resistivity, carrier concentration, and mobility with the standard Hall‐effect technique. The noncontact techniques examined are far‐infrared reflection, Raman scattering, eddy–current absorption, and electroreflectance. Of these techniques, far‐infrared reflection was found to be the best noncontact technique for measuring resistivity, carrier concentration, and mobility. Resistivity values were within a factor of 2 of Hall‐effect values, while carrier concentration and mobility values that depend on an assumed effective mass were within a factor of 3. In Raman scattering, interference between the free‐carrier plasmon–phonon mode and other modes makes it an inaccurate method for estimating carrier concentration. Eddy–current absorption is useful for quickly measur...

1/f noise in Hg0.7Cd0.3Te photodiodes has been measured as a function of temperature, junction area, diode voltage, and gate bias in order to identify the dominant noise mechanisms. The p‐n junctions were formed both by ion implantation and by growth of double‐layer epitaxial structures. The LPE base layers were doped with arsenic and the devices were passivated with photochemically deposited SiO2. Two leakage current mechanisms were identified as sources of 1/f noise. Under optimized surface potentials, the 1/f noise was proportional to the depletion‐region GR current generated at the surface. This was observed in both double‐layer devices in which the leakage current was primarily generated at the depletion‐region surface, and in ion‐implanted devices in which the leakage current had a bulk depletion‐region origin. For nonoptimized gate voltages, where tunneling currents were the dominant leakage mechanism, the noise current was proportional to the tunneling current. Surface, bulk, and photogenerated diffusion currents were not accompanied by significant amounts of 1/f noise. The proportionality factor between the noise current and the depletion‐region leakage current for the devices passivated with SiO2 was found to range from one to ten times lower than the values previously reported for ZnS‐passivated devices. The results are discussed terms of Handel’s bremsstrahlung model, Kleinpenning’s mobility fluctuation model, and the McWhorter–Anderson–Hoffman surface potential fluctuation model.

We develop a set of sufficiency conditions which guarantee that certain Reggeon amplitudes satisfy good finite-mass sum rules. We present and analyze a specific and simple model amplitude which embodies these conditions.

The results of photoluminescence analysis of ion‐implanted and flash‐annealed CdTe are reported here. Bound exciton lines in the spectrum of the CdTe were used to study the annealing of implantation‐induced damage in the crystal. The intensity and width of these lines are a very good indicator of variations in lattice strain. Optimum flash annealing conditions were found to depend on both the energy and the dose of the implant. The photoluminescence indicates that flash annealing can provide complete annealing of the crystal damage following implantation. Implanting Cu or B ions into the lattice did not, however, lead to significant variations in the spectrum of the samples as compared to annealed, unimplanted samples. A comparison of flash and furnace annealing was made.

We generalize the path integral formalism of quantum mechanics to include the use of arbitrary infinitesimal generators, thus providing explicit expressions for solutions of a wide class of differential equations. In particular, we develop a method of calculating the eigenfunctions of a large class of operators.

It has been previously shown that 30-day experimental left varicocele (ELV) in adult rats produces a bilateral increase in testicular blood flow and temperature, as well as a concomitant decrease in epididymal sperm count and motility. In the present study, adult male rats with induced ELV were subjected to a variety of studies to determine the mechanism by which unilateral ELV causes a bilateral testicular response. The results demonstrate that ELV does not alter the blood-testis barrier (BTB) to 3H-inulin (MW 5000), it being largely excluded from entry into the tubule lumen in both control and ELV animals. Neither left nor right cauda epididymidal temperature was altered by ELV. Intraepididymal Na+ and K+ concentrations in the left caput epididymidis were 81.3 +/- 3.8 mEq/l and 26.3 +/- 1.5 mEq/l, respectively. From the cauda epididymidis, these values were 25.0 +/- 2.2 mEq/l and 46.8 +/- 1.0 mEq/l, respectively. These values were similar on the right side and in the left and right epididymis of ELV animals. Left testis arterial pH was 7.3 +/- 0.1, and PO2 and PCO2 were 116.0 +/- 6.4 mm of mercury and 44.3 +/- 3.2 mm of mercury, respectively. Left testicular venous values were 7.3 +/- 0.1 (pH), and 52.6 +/- 2.2 mm of mercury and 49.9 +/- 2.0 mm of mercury. These values were similar for right control testicles and left and right testicles of ELV animals. These results indicate that the mechanism by which unilateral ELV produces a bilateral change in testicular or epididymal function is not by altering the BTB, epididymal temperature or electrolyte concentrations, or testicular blood gas concentrations.

Electron traps in bulk n‐type Hg0.7Cd0.3Te were investigated near the HgCdTe/SiO2 interface by use of deep level transient spectroscopy on metal‐insulator‐semiconductor structures [D. V. Lang, J. Appl. Phys. 45, 3022 (1974)]. Three electron traps are found with activation energies (relative to the conduction band edge) of 0.12, 0.172, and 0.079 eV, and corresponding capture cross sections of 3.5×10−18, 1.1×10−16, and 1.2×10−18 cm2. Depth profiles from the surface to ∼1.0 μm show the concentration of the 0.172‐eV trap to be uniform while the 0.12‐eV trap shows a strong depth dependence. It is undetectable at the surface, rising in concentration to twice its bulk value at ∼0.5 μm depth then falling to a value comparable with that of the 0.172‐eV trap in the bulk (1 μm). Divalent trapping behavior has also been detected. In this case, the deeper state significantly depopulates, enabling a shallower state to then depopulate [J. S. Blakemore, Semiconductor Statistics (Pergamon, London, 1962), p. 156].

Left ventricular responses to 2-min circumflex occlusion were studied in conscious dogs. In nonsympathectomized controls at 2, 4, and 8 wk after surgery for cardiac instrumentation, segmental shortening in the posterior ventricle significantly decreased by 111, 87, and 81% of the preocclusion values, respectively (P less than 0.05). The decrease in shortening was associated with increases in end-diastolic pressure of 9, 9, and 8 mmHg (P less than 0.05), decreases in the maximal rate of pressure generation of 305, 272, and 340 mmHg/s (P less than 0.05), and increases in heart rate of 28, 21, and 20 beats/min, respectively (P less than 0.05). After 2 and 4 wk of ventricular sympathectomy, posterior segmental shortening declined by 38 and 31%, respectively (P less than 0.05), but these decreases were less than in controls (P less than 0.05). Shortening did not change during occlusion after 8 wk of sympathectomy. Diastolic pressure increased by 6 mmHg (P less than 0.05), and the rate of pressure generation decreased by 232 mmHg/s (P less than 0.05) in the 2-wk sympathectomized ventricle. These variables did not change significantly after 4 and 8 wk of sympathectomy. After 2, 4, and 8 wk of sympathectomy, the increases in heart rate during circumflex occlusion were not different from controls (P greater than 0.05). Thus chronic sympathectomy preserved ventricular function during occlusion. This effect was attributable to a reduced preocclusion mechanical performance with a reduction in blood flow requirement and to an increased collateral perfusion, as indicated by a higher peripheral coronary pressure during occlusion in sympathectomized ventricles.

A new formulation of nonrelativistic scattering theory is developed which expresses the S matrix as a path integral. This formulation appears to have at least two advantages: (1) A closed formula is obtained for the S matrix in terms of the potential, not involving a series expansion; (2) the energy-conserving δ function can be explicitly extracted using a technique analogous to that of Faddeev and Popov, thereby yielding a closed path-integral expression for the T matrix. The introduction of the concept of the classical interaction picture provides considerable physical insight into this formulation. Finally, this formulation also suggests a succession of improvements to the eikonal approximation, the first of which is discussed explicitly.

The role of adenosine in pacing-induced hyperemia was examined in 10 dogs. Left coronary blood flow (LCBF), left ventricular O2 extraction [(a-v)O2], and myocardial O2 consumption (MVO2) were monitored. Heart rate (HR) was initially paced at 120 beats/min and then increased to 180 beats/min to elicit a hyperemic response (delta LCBF). During the hyperemia, the vasodilatory response to exogenous adenosine (FAd) was tested. HR was then returned to the initial level, and 20 min after injection of aminophylline (100 mg iv) HR was again increased to 180 beats/min. The response to adenosine was again tested. The pacing-induced increase in MVO2 (delta MVO2) was not affected by aminophylline (P greater than 0.05). However, after aminophylline, the flow response slope delta LCBF/delta MVO2 was decreased by about 20% (P less than 0.05), and the extraction-response slope delta (a-v)O2/delta MVO2 was increased by 100% (P less than 0.05). FAd was also decreased by aminophylline, and the magnitude of the reduction was correlated with the decrease in the flow-response slope (r = 0.82). These results suggest that endogenous adenosine may play an important role in coronary functional hyperemia induced by increases in heart rate.

The photoreduction of adsorbed dye (methyl red and crystal violet) sensitized by chlorophyll a in an anionic mineral oil in water microemulsion system has been investigated. The 100-A microdroplets occupy 40% of the total volume, and at the pigment concentrations employed (less than or equal to 10 ..mu..M) there is on the average less than one chlorophyll molecule per drop. Using ascorbate as the water-soluble reducing agent, the reaction exhibits a pseudo-first-order dependence on crystal violet, but a pseudo-zero-order dependence on methyl red. The chlorophyll fluorescence is quenched by methyl red, but not by crystal violet. The effect of sensitizer and of ascorbate concentration and light intensity on the quantum yield has also been examined. From the results of these and auxiliary studies, a reaction mechanism is proposed which involves the formation of a chlorophyll-dye triplet exciplex rather than the initial formation of an oxidized or reduced pigment species. Based on this scheme, a number of rate constants have been estimated.

The antibody domain controlling reactions between platelet membranes and drug-dependent (dd) antibodies from patients with thrombocytopenia induced by cinchona alkaloids was studied using F(ab')2, Fab, and Fc fragments made from purified dd-IgG. By direct binding radioimmunoassay (RIA) measurements, 20,000 to 50,000 antibody molecules bound per platelet equivalent of purified platelet membranes at apparent saturation with three different antibodies. F(ab')2 and Fab fragments bound to platelet membranes drug dependently but Fc fragments did not. The ability of dd-IgG fragments to compete with intact IgG was quantitatively measured by RIA and by complement fixation. F(ab')2 and Fab competed with intact IgG at an 8:1 and greater than 50:1 molar ratio, respectively, in RIA, and at a 1.6-3:1 and 44-75:1 ratio, respectively, by complement fixation assays. Fc did not compete with IgG in either assay. We conclude that the Fab domain supports attachment of dd antibody to the platelet surface.

The control of androgen concentrations in the intraluminal fluids of the male reproductive tract is not well understood. The present experiments were performed to determine the effects of hypophysectomy, hypophysectomy plus testosterone (T), and hypophysectomy plus pregnenolone treatment on intraluminal androgen concentrations in the adult rat testis and epididymis. T and 5 alpha-dihydrotestosterone (DHT) concentrations were determined in the vascular, interstitial, and intraluminal compartments of the epididymis. Testicular and epididymal morphology also were examined under light microscopy. Hypophysectomy of at least 5 days duration significantly reduced T and DHT concentrations in serum, tissues, and intraluminal fluids of the reproductive tract. T replacement for 14 days, which produced peripheral T concentrations of 5 ng/ml, did not support intraluminal androgen concentrations in the seminiferous tubules equivalent to controls; rete testis androgen concentrations were similar to controls, however. Pregnenolone administration at 2 mg X rat-1 X day-1 for 14 days did not maintain spermatogenesis nor intraluminal T concentrations in the seminiferous tubules equivalent to controls; however, a low level of spermatogenesis continued when intraluminal and tissue androgen concentrations were maintained at 10-20% of controls by either the testosterone and pregnenolone treatments.

For purely hadronic processes, the standard connection between spin and statistics as well as separate invariances under charge conjugation, parity, and time reversal are shown to be consequences of self-consistency in topological particle theory. I. INTRODUCTION In the preceding work' (referred to hereafter as FJ) the phases for zero-entropy terms in the topological expansion were determined through systematic enforcement of the requirements of pole factorization, Hermitian analyticity and crossing symmetry. In this paper we investigate the spin and statistics properties of these zero-entropy terms and also their invariance properties under parity, timereversal, and charge-conjugation transformations. All these properties are shown to follow from self-consistency considerations and a knowledge of the amplitude phases derived in FJ. In Sec. II the theory is shown to obey the standard spin and statistics relations. The proof differs considerably from an S-matrix proof of spin and statistics given a number of years ago by Stapp, since these topological amplitudes are not unitary at the zero-entropy level. We also show (Secs. III, IV, and V) that the zero-entropy sum is separately invariant under parity, time-reversal, and charge-conjugation transformations. The zero-entropy level and higher corrections arising from connected sums of these zero-entropy terms represent hadronic processes so we have been able to prove the existence of the standard discrete symmetries for strong interactions as well as the standard statistics. It should be emphasized that these symmetries were not built into the theory. Only requirements of self-consistency, pole factorization, crossing symmetry and Hermitian analyticity are used together with a standard discontinuity equation which embodies the dynamics. Again these results should be contrasted with Stapp's original work where the product of these three symmetries was shown to hold for the full unitary S matrix. The discussion of the discrete invariances is carried out in the framework of the topological bootstrap theory. After defining the invariances we simply investigate whether the amplitude for a process has the same absolute value as the appropriately transformed process. It is not therefore necessary to define the action of these symmetry transformations on individual incoming or outgoing state vectors. Thus many tiresome phase questions are avoided and yet any physically observable phases (such as those associated with intrinsic parities ) are unambiguously evident. The study of electroweak processes within the framework of the topological theory shows that the amplitudes for such processes appear above the zero-entropy level where the discrete symmetries no longer hold separately. The topological theory thus provides a basis for understanding the presence of the separate discrete symmetries in certain (strong) processes as well as their absence in other (weak) processes.

We report the application of diode admittance spectroscopy in characterizing traps in Hg1−xCdxTe. Measurements performed on n+‐p junction photodiodes have identified a hole trap located 0.16 eV above the valence band in x=0.305 liquid‐phase‐epitaxy‐grown material and a single hole trap located 0.046 eV above the valence band in x=0.219 bulk‐grown material. Measurements of trap density and majority‐carrier capture cross section have also been carried out, with results suggesting hole capture at a neutral trapping center. Trap energies determined by the admittance spectroscopy technique were found to be in good agreement with lifetime‐versus‐temperature data analyzed in terms of a single Shockley‐Read recombination center.

From the requirement of reality of discontinuities of scattering amplitudes at the spherical level of the topological bootstrap theory, a large number of mass relations for hadrons is derived. Quadratic mass formulas for the symmetry-breaking pattern of both mesons and baryon is obtained and their relation to conventional models of symmetry breaking is briefly discussed.

The participation of endogenous opiates in myocardial performance and coronary blood flow was investigated. Heart rate, left ventricular contractile force (LVCF), left coronary blood flow (LCBF), and left ventricular oxygen extraction were monitored in anesthetized dogs before and after intracoronary opiate receptor blockade with naloxone. LVCF consistently increased in a dose-dependent fashion following intracoronary naloxone. The increasing LVCF was accompanied by significant increases in LCBF and myocardial oxygen consumption, without changes in heart rate. Rapid onset of responses suggested the presence of endogenous opiates operating locally within the myocardium. Similar effects did not follow right atrial injection of naloxone, ruling out a systemic mechanism. Furthermore, naloxone injected into the isolated left anterior descending artery selectively increased contractile force in that perfusion territory while the adjacent untreated circumflex territory showed no change. The administration of dynorphin into the coronaries produced a depression of LVCF qualitatively consistent with these effects. The effect of dynorphin was subsequently reversed with naloxone. These results support the concept that endogenous opiates participate in the regulation of myocardial function through local mechanisms at the myocardial level.

Experiments were performed to determine whether total, specific cardiac denervation affects the renal responses of the nonhuman primate to acute intravascular volume expansion. Adult male Macaca fascicularis monkeys underwent chronic intrapericardial cardiac denervation or sham surgery. After a 14- to 30-day recovery period, each animal was anesthetized with sodium pentobarbital and estimated blood volume was volume-expanded 20% with 6% dextran in isotonic saline. Control renal excretory function did not differ between the two groups, and both groups had similar increases in urine flow, sodium and potassium excretion, osmolar clearance, free water clearance, and renal plasma flow after volume expansion. The times to peak diuresis and natriuresis also were similar in both groups. These results demonstrate that the cardiac-denervated monkey shows unattenuated renal excretory responses to volume expansion. This could indicate that either cardiac receptors do not play a major role in eliciting these responses in the primate or that eliminating a role of cardiac afferents is compensated for by redundant afferents from arterial baroreceptors.

We derive an upper bound on the triple-Pomeron coupling g/subP/ /sup 2/(0) assuming the actual Pomeron is a pole below one. Our result corresponds to an estimate of g/subP/ /sup 2/(0) obtained by Abarbanel, Chew, Goldberger, and Saunders on the basis of a multiperipheral model. We show that if indeed the bound is an estimate of g/subP/ /sup 2/(0), Pomeron exchange in multiparticle production should constitute a significant fraction of the total cross section. We indicate how this can be true even in the limit of vanishing Pomeron couplings. It is also shown how our calculation can be applied to obtain a bound on the ''bare'' triple-Pomeron coupling. (AIP)

Trapping effects in p‐type Hg1−xCdx Te (0.2

This paper reviews the status of point defect studies in HgCdTe and presents new data on the characterization of impurities in CdTe, on shallow and deep acceptors in arsenic‐doped HgCdTe, and on the ability of electron paramagnetic resonance (EPR) to detect defects in HgCdTe. Point defects are important in controlling carrier concentrations, minority‐carrier lifetimes, and noise in HgCdTe. Shallow impurities from dopants are fairly well understood and their effects follow what is expected from the periodic table. Intrinsic defects such as the mercury vacancy, which is believed to act as a shallow acceptor, are less well understood and suffer from a lack of characterization techniques that can identify individual defects. Deep‐level defects are present with concentrations proportional to the shallow acceptor concentrations. These centers often control lifetime and noise. Many of these have been electrically characterized, but not identified. Theoretical work by several groups to calculate defect levels has begun. At present, the errors in this work are larger than the HgCdTe band gaps, but the calculated trends are important. Experimental data on identified deep levels are needed both for guiding material improvement and for improving the theoretical modeling.This paper reviews the status of point defect studies in HgCdTe and presents new data on the characterization of impurities in CdTe, on shallow and deep acceptors in arsenic‐doped HgCdTe, and on the ability of electron paramagnetic resonance (EPR) to detect defects in HgCdTe. Point defects are important in controlling carrier concentrations, minority‐carrier lifetimes, and noise in HgCdTe. Shallow impurities from dopants are fairly well understood and their effects follow what is expected from the periodic table. Intrinsic defects such as the mercury vacancy, which is believed to act as a shallow acceptor, are less well understood and suffer from a lack of characterization techniques that can identify individual defects. Deep‐level defects are present with concentrations proportional to the shallow acceptor concentrations. These centers often control lifetime and noise. Many of these have been electrically characterized, but not identified. Theoretical work by several groups to calculate defect levels has...

We developed algorithms for confirmation and identification of benzodiazepines and their metabolites, initially detected in urine samples by enzyme-multiplied immunoassay (EMIT). These algorithms are based on the pattern of benzophenone derivatives of benzodiazepines obtained by gas chromatography-mass spectrometry (GC-MS) with use of a modified specific ion selection mode. Benzophenone derivatives were produced by acid hydrolysis of urine samples containing benzodiazepines and (or) their metabolites. We present mass spectra of the newer benzodiazepines--alprazolam, midazolam, and triazolam--and we determined the detection limit (0.2 mg/L) for these drugs as measured with the EMIT d.a.u. benzodiazepine assay and the ETS instrument (both from Syva Co.). We conclude that these algorithms are useful mostly in forensic toxicology in which unequivocal identification of benzodiazepines is the desired goal.

An investigation is made of how close to one a Pomeron pole can be before the decoupling mechanisms make the total pion-pion cross section too small to be consistent with that deduced from experiment by means of factorization. Our method employs energy-momentum sum rules for singly and doubly inclusive cross sections. Assuming pion pole dominance in the forward direction, enables elimination of the triple-Pomeron coupling which leaves an inequality involving only the Pomeron pole location and the pion-Pomeron coupling. From this it is concluded that the decoupling mechanism is exceedingly weak. (AIP)

Deep‐level defects play an important role in determining minority carrier lifetimes and noise in Hg1−xCdxTe devices. Previous work on deep‐level defects in Hg1−xCdxTe has been meager because there have not been good experimental methods available to observe or characterize them. Deep‐level transient spectroscopy has now begun to provide information on concentrations, energy levels, and capture cross sections for defects in Hg1−xCdxTe. This paper reviews the DLTS results to date on nonstoichiometric (Hg lean) and copper‐doped material. In both cases, trends are beginning to appear for the trap levels as a function of x. Nonstoichiometric material commonly shows generation‐recombination centers at Ev+0.4 Egap and Ev+0.75 Egap. Copper‐doped material commonly shows two levels pinned to the valence band at about Ev+0.06 eV and Ev+0.15 eV. The capture cross sections and concentrations measured by DLTS have been used to calculate the effect these centers have on minority carrier lifetime and noise (R0A). In most...

Gold is a fast‐diffusing acceptor in HgCdTe. It has been used as a p‐type dopant and as a metal contact. This paper reports the presence of deep levels in gold‐doped x=0.48 Hg1−xCdxTe. Two types of spectra were observed; each had energy levels between Ev +1/4 Egap and Ev +1/2 Egap. The capture cross sections for these centers have been determined and for most of the levels they involve small hole capture cross sections, 10−17 to 10−21 cm2, and moderate electron capture cross sections, 10−15 to 10−16 cm2. The hole capture cross sections for these centers had large negative activation energies indicative of hole capture at a positive center with a Coulomb repulsive barrier. The corresponding electron capture is then at Coulombically attractive positive centers. The situation described requires that the DLTS activation energies be corrected for the temperature dependence of the hole capture cross sections and for the Poole–Frenkel effect for electron capture. The energy levels and capture cross sections repo...

We generalize the path integral technique of quantum mechanics to provide direct expressions for energy eigenfunctions. We illustrate our technique with the harmonic oscillator.

The complex admittance of an n‐type Hg1−xCdxTe/Photox SiO2 interface with x=0.3 has been examined for frequencies ranging between 1 mHz and 4 MHz. The conductance method is used to decompose the total interface state density into three types of components: a valence‐band tail, a conduction‐band tail, and some well‐resolved discrete states. The fixed charge density is low and there is no statistical broadening. The surface valence‐ and conduction‐band edges are both found to be shifted upward in energy relative to their respective bulk values; moreover, the surface has converted to p type. The energy variation of the valence‐band tail states response times follows a pattern characteristic of Shockley–Read recombination centers with a constant capture cross section, but the behavior of the conduction‐band tail states is more complicated. Evidence is presented that the interface region has a higher Cd concentration than the bulk.

The A0 X band at 1.5896 eV is the dominant feature in the low‐temperature luminescence from most samples of as‐grown CdTe. This band has been associated with Cu by Chamonal et al., because it increased after copper evaporation and furnace annealing at 800 °C for 2 h. In other work, this line at 1.5896 eV is seen to increase in intensity following annealing, whether Cu has been intentionally introduced into the sample or not. In order to eliminate the ambiguities inherent in furnace annealing, we have used ion implantation and rapid thermal annealing to activate the dopant. A Kr implanted sample was used as a reference to identify Cu related effects. The variation of implant activation with implant temperature was studied. It was found that activation of the center responsible for the 1.5896‐eV line was dependent more on substrate history than implant temperature, within the temperature range studied. The 1.5896‐eV line and a donor–acceptor pair band at 1.45 eV increased in intensity in the spectra from th...

We discuss the analytic continuation of an azimuthal angular variable in a scattering process to a channel where it may take on large imaginary values. The asymptotic behavior of the many-particle amplitude for large values of that variable is shown to be governed by singularities in an analytically continued helicity amplitude. The procedure is analogous to the usual Regge-Sommerfeld-Watson transformation relating large-$cos\ensuremath{\theta}$ behavior to singularities in analytically continued angular momentum amplitudes.

We extend a previous treatment [1] of O (2, 1) expansions for nonsquare-integrable many particle amplitudes to the case where one “incoming” and one “outgoing” cluster have space-like O (2, 1) momenta.