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This paper proposes a new equivalent circuit for induction motors having the harmonic components. The proposed circuit consists of T-type equivalent circuit and LC resonant circuit, which is connected in parallel with load resistance. Various features of the induction motors including harmonics can be easily obtained by the proposed circuit. The fundamental component is expressed by the conventional output resistance, and the ripple elements of the mechanical output are represented by the current flowing in the LC parallel resonant circuit. In the proposed equivalent circuit, the current flowing into the load resistance becomes sinusoidal, so that we can separate ripple components from fundamental one. It is necessary to decide the appropriate values of L and C as the resonant frequency that gives the fundamental frequency. Strictly speaking, the resonant frequency is denoted by rotor speed. By means of this circuit, various harmonic torque characteristics can be easily obtained.

Capacitor input-type rectifier circuits are generally employed in small-capacity rectifier circuits, such as those used for consumer electronics and appliances. Consequently, the various harmonics that are generated in the power system become a serious problem. Various studies of these issues have been reported. However, most of those methods employ switching devices, such as FETs and the like. The absence of switching devices makes systems more tolerant to over-load, and brings other benefits in terms of low EMI noise. We propose a power factor correction scheme using cycle-control for commercial frequencies without the need for high frequency switching devices, in this paper, we attempted to use a passive element including a proposed novel PFC circuit that includes cycle-control to obtain a reduced output voltage. In order to avoid the generation of various harmful harmonics during cycle-control, a novel divided capacitor-type rectifier circuit is proposed. It is very easy to reduce the harmonics in this circuit. The results are confirmed by simulated and experimental implementations

This paper reports 65-nm node ultra-low standby power CMOS technology for mobile applications, utilizing the combination of HfSiON FET and back-biasing scheme for the first time. With well-optimized channel, offset-spacer and halo conditions, physical gate length is successfully scaled down to 55 nm with excellent V/sub th/ roll-off and small DIBL, for both surface channel nFET and buried channel pFET. The record I/sub on//I/sub off/ ratio, the drive current of 510/220 /spl mu/A//spl mu/m with off-state leakage of 20/20 pA//spl mu/m, are obtained. We have also demonstrated body-biasing scheme feasibility for further subthreshold leakage (I/sub subth/) reduction. By exploiting Fermi-level-pinning effect, we have reduced the channel doping concentration and suppressed gate induced drain leakage (I/sub GIDL/) even under reverse body-biasing condition. Total standby leakage (I/sub subth/+I/sub GIDL/+I/sub g/) are reduced to 1.4/0.32 pA//spl mu/m at V/sub dd/= 0.8 V and Vb= /spl plusmn/1 V, which is the smallest value ever reported for 65nm-node LSTP.

In the fields such as various electric power compensators and ac motor drives, large capacity and high-performance converters are placed into practical applications. For these converters, since the upper limit of the switching frequency is low and capacity of device is insufficient, method of connecting the device in series and parallel would be effective. From such reasons, for improving the harmonic characteristics, various multi-level inverters have been reported, in which it is necessary to provide some dc power supplies connected in series that is disadvantage for this inverter. We propose a simple dc-dc converter for adjusting the power supply voltages of this inverter. By means of this dc-dc converter circuit, the voltages of four dc power supplies of five-level inverter can be suitably controlled towards the desired value. The circuit characteristics are discussed by theoretical and simulated procedures. The theoretical results and the simulated ones are in agreement with each other.

The conventional boost converters can be generally used for rectifier circuits with power factor correction, while the output voltage can not be adjusted over a wide range. In a case of expanding the controlled voltage range, buck-boost type including Cuk converter should be employed. This paper discusses an optimum circuit configuration for power factor correction. Single-phase power factor correction using a buck boost converter can control the output voltage over a wide range, because it has the ability to step-up and step-down the output voltage. Firstly, this paper compares the mechanisms of the proposed power transmission technique and the characteristics based on the voltage and the current ripple in terms of EMI noise. Secondly, these converters are applied to the single-phase power factor correction. It is found that the CSC (Canonical Switching Cell) is the best choice and selected as the optimum PFC.

Capacitor input-type rectifier circuits are generally employed in small-capacity rectifier circuits, such as those used for consumer electronics and appliances. Consequently, the various harmonics that are generated in the power system become a serious problem. Various studies of these issues have been reported. However, most of those methods employ switching devices, such as FETs and the like. The absence of switching devices makes systems more tolerant to over-load, and brings other benefits in terms of low EMI noise. We propose a power factor correction scheme using cycle-control for commercial frequencies without the need for high frequency switching devices. It is very easy to reduce the harmonics in this circuit. The results are confirmed by simulated and experimental implementations

The line impedance could be measured by means of only passive elements such as inductors or resistors, that is presented at first. However, as the voltage and current used for the measurement are increased, the size of the inductor or resistor being used also needs to be increased, so in practice it would be virtually impossible to make an accurate measurement. Because of this, we have developed a novel measurement method for line impedance using an inverter circuit, which we describe secondly. In the third place, we propose another line impedance measurement method. The novel method is that the high frequency wave with minimum voltage is injected into the distribution line system. By means of this method, the line capacitance and the line inductance can be measured. These proposals are confirmed by the simulation or experiment

In the fields such as various electric power compensators and ac motor drives, large capacity and high-performance converters are wished to be put into practical applications. For these converters, since the upper limit of the switching frequency is low and capacity of device is insufficient, method of connecting the device in series and parallel would be effective. From such reasons, for improving the harmonic characteristics, various multi-level inverters have been reported, in which it is necessary to provide some dc power supplies connected in series that is disadvantage for this inverter. We propose a simple dc-dc converter for adjusting the power supply voltages of this inverter. By means of this dc-dc converter circuit, the voltages of four dc power supplies of five-level inverter can be suitably controlled towards a desired value. The circuit characteristics are discussed by theoretical and simulated procedures. The theoretical results and the simulated ones agree with each other.

The authors propose a 120-degree beamwidth slot array antenna with a three-way power divider using post-wall waveguides installed on a single-layer substrate. The antenna is designed for base stations in 26 GHz-band fixed wireless access systems (FWA). It is easily manufactured at low cost for mass production by making via-holes and metal plating for the post-wall waveguides and etching for the slot array. In the vertical plane, a cosecant beam pattern is synthesized with null filling in order to get uniform illumination over the coverage area.

We have newly developed poly-Si/a-Si/HfSiON (EOT=1.6nm) transistor that features high I/sub on/-I/sub standby/ ratio and reliability for 65nm-node LSTP (Low Standby Power) application. By carefully optimizing halo implant condition, excellent I/sub on/-I/sub standby/ (=I/sub g/I/sub off/) characteristics of I/sub on/=520/spl mu/A/I/sub standby/=17pA (I/sub g/=1.6pA, I/sub off/= 15pA) at V/sub dd/=1.2V are obtained, which is the highest ratio ever reported. In addition, we have newly introduced thin amorphous-Si layer between HfSiON and phosphorous-doped poly-Si gate-electrode for reliability enhancement, and confirmed that PBTI (positive bias temperature instability) lifetime improves by two orders of magnitude with no performance degradation. We believe this technology enables further device scaling of poly-Si/HfSiON structure.

Various nonlinear semiconductor circuits have been used in consumer and industrial electronics. It is well known that rectifier circuits such as these can generate various harmonics within a power system. Because of this, several different power factor correction circuits have been proposed and studied. These methods are designed to improve the input current to a sinusoidal waveform by using switching devices, and they therefore degrade the cost performance. From this point of view, it is also appropriate to discuss harmonic reduction methods that do not use switching devices. This paper proposes some rectifier circuits for power factor correction that operates without switching devices, and whose input current waveform is almost sinusoidal. Since it does not make use of any switching devices, this solution avoids any losses and noise due to switching. In addition, since it is also unnecessary to employ a complicated driving circuit, it is favorable in terms of cost performance. The effectiveness of this circuit is confirmed by simulation and experiment.

Multi-level PWM inverters have significant advantages such as the ability to operate the motor with nearly sinusoidal current waveforms and higher output voltages. In order to increase the inverter size, the parallel connection method would be effective for the present. In high-power applications, for instance, the carriers should be synchronized to modulating sinusoidal waves. Moreover, for the interphase reactor, lower order harmonic application is prohibited. In practice, to improve the harmonic characteristic of the parallel-connected five-level inverters, various modulation strategies are devised and designed in this paper. It is found that the DC current flow of DC power supplies can be controlled by means of phase shifting of the injected third order harmonics or modifications of them. In the case of the SVC (static VAr compensator), by means of this technique, the output capacitor voltages could be controlled individually.

A logic-process-compatible low-temperature hemispherical grain (HSG) cylinder capacitor process with maximum process temperature below 700/spl deg/C is developed. Depletion in HSG-grains and top-electrodes due to decreasing thermal budget is effectively suppressed by phosphorus doping with PH/sub 3/-annealing and the use of metal plate-electrodes. By combining with the HSG grain size optimization, the low-temperature process with highly reliable oxynitride (ON) dielectrics can be applied to high density embedded DRAM cells down to 0.13 /spl mu/m design rules.

A new method for the control system design of AGVs is proposed in the paper. The control system design can avoid a prohibited situation and a deadlock, and also evaluate the rule and AGV number. The control system is applied to the AGV of a factory production line system. Its effectiveness is confirmed by SIMAN/CINEMA simulation. >

This paper is the first report on the detrimental current crowding effect in the power grid structure of gate arrays. Innovative solutions to the problems are described. The proposed power routing technique utilizes flexible metalization with respect to the power pad locations. The resulting structure improves gate utilization and prevents metal electromigration. The CAD physical design flow for implementation in a 0.5 /spl mu/m CMOS sea-of-gate array is described. >

We achieved a novel low voltage operating flash memory cell with high coupling ratio of 0.9 which has a horned floating gate (FG) with fine HSG. The increase in the coupling ratio can reduce programming and erasing operation voltages by a maximum 4 V. Enlargement of the FG surface area by extending in the vertical direction enables the high coupling ratio without increasing cell area. In addition, the increase in the coupling ratio is significant when cell size is shrunk. We consider the horned FG cell with HSG as the most promising candidate for the flash memory cell in 0.25 and 0.18 /spl mu/m design rules.

The electrical characteristics and gate lengths of individual MOSFETs are evaluated by a test structure with a Kelvin pattern as the gate electrode. The gate length measurement by SEM can be substituted by the electrical measurement using this test structure. Excellent correspondence is obtained between the threshold voltage lowering in the short channel region and the electrically measured gate length. Furthermore, the precision of drain-to-gate overlap length is improved by applying the effective channel length extraction method to the electrically measured gate length instead of the commonly used designed gate length.

In general, the harmonics in a power system are measured with a heterodyne receiver if one is using analog methods or by a FFT (Fast Fourier Transform) when digital methods are being used. The harmonics can be analysed over a wide range of frequencies by means of these methods. However, since the circuit configurations that are needed can become very complicated, the equipment tends to be too expensive for practical use. This paper presents a novel harmonic meter using a PLL (phase locked loop) circuit. By means of the phase feedback loop, a reference sinusoidal wave is locked on to the input signal along with the harmonics that one wishes to measure, and hence the corresponding harmonic component in the input signal is easily detected. The effectiveness of the proposed harmonic meter is confirmed by experiment.

The various harmonics in a power system are typically measured with a heterodyne receiver if we are using analog methods or by a FFT (fast Fourier transform) when digital methods are being used. The harmonics can be analysed over a wide range of frequencies by means of these methods. However, since the circuit configurations that are needed can become very complicated, the equipment tends to be too expensive for practical use. This paper presents a novel harmonic meter using a PLL (phase locked loop) circuit. By means of the phase feedback loop, a reference sinusoidal wave is locked on to the input signal along with the harmonics that we wish to measure, and hence the corresponding harmonic component in the input signal is easily detected. The effectiveness of the proposed harmonic meter is confirmed by experiment.

Various nonlinear semiconductor circuits have been used in consumer electronics and industrial electronics. It is well known that rectifier circuits such as these can generate various harmonics within the power system. Because of this, several different power factor correction circuits have been proposed and studied. These methods are designed to improve the input current to a sinusoidal waveform by using switching devices, and they therefore degrade the cost performance. From this point of view, it is also appropriate to discuss harmonic reduction methods that do not use switching devices. This paper proposes a novel three-phase rectifier circuit for power factor correction that operates without switching devices, and whose input current waveform is almost sinusoidal. Since it does not make use of any switching devices, this solution avoids any losses and noise due to switching. In addition, since it is also unnecessary to employ a complicated driving circuit, it is favorable in terms of cost performance. The effectiveness of this circuit is confirmed by simulation and experiment.

Various nonlinear semiconductor circuits have been used in consumer electronics and industrial electronics. It is well known that rectifier circuits such as these can generate various harmonics within the power system. Because of this, several different power factor correction circuits have been proposed and studied. These methods are designed to improve the input current to a sinusoidal waveform by using switching devices, and they therefore degrade the cost performance. From this point of view, it is also appropriate to discuss harmonic reduction methods that do not use switching devices. This paper proposes a novel three-phase rectifier circuit for power factor correction that operates without switching devices, and whose input current waveform is almost sinusoidal. Since it does not make use of any switching devices, this solution avoids any losses and noise due to switching. In addition, since it is also unnecessary to employ a complicated driving circuit, it is favorable in terms of cost performance. The effectiveness of this circuit is confirmed by simulation and experiment.

For small capacity rectifier circuits with a small capacity, such as those for consumer electronics and appliances, capacitor input type rectifier circuits are generally used. Consequently, various harmonics generated within the power system become a serious problem. Various studies of this effect have been presented previously so far. However, most of these employ switching devices, such as FETs and the like. The absence of switching devices makes systems more tolerant to over-load, and brings low radio noise benefits. The authors propose a power factor correction scheme using a voltage doubler rectifier without switching devices. In this method, the input current is divided into two periods, where one period charge the small input capacitor and the other charge the large output capacitor. By dividing the input current into two different modes, the current conduction period can be widened and harmonics can largely be canceled between the two modes. Hence, the harmonic characteristics can be significantly improved, whereby the lower order harmonics, such as the fifth and seventh orders, are much reduced. The results are confirmed by theoretical and experimental implementations.

For small capacity rectifier circuits with a small capacity, such as those for consumer electronics and appliances, capacitor input type rectifier circuits are generally used. Consequently, various harmonics generated within the power system become a serious problem. Various studies of this effect have been presented previously. However, most of these employ switching devices, such as FETs and the like. The absence of switching devices makes systems more tolerant to over-load, and brings low radio noise benefits. We propose a power factor correction scheme using a voltage doubler rectifier without switching devices. In this method, the input current is divided into two periods, where one period charges the small input capacitor and the other charges the large output capacitor. By dividing the input current into two different modes, the current conduction period can be widened and harmonics can largely be cancelled between the two modes. Hence, the harmonic characteristics can be significantly improved, whereby the lower order harmonics, such as the fifth and seventh orders, are much reduced. The results are confirmed by theory and experiment.

Introduction Studies using primary health care settings to promote literacy have demonstrated success. Since socioeconomically disadvantaged children have less access to primary care, obtaining much of their medical care episodically in emergency departments (ED), the purpose of this study is to investigate the effectiveness of a simple literacy promotion program conducted in the ED and to determine its efficacy and if there is a difference in promoting literacy with a brochure alone versus a brochure plus a children’s book. Methods Medical student study investigators enrolled patients aged 20 months to 7 years undergoing acute care treatment and evaluation in an ED. Subjects were randomized to a literacy promotion brochure versus a brochure plus a children’s book. Phone follow-up interviews were conducted to survey the degree of parental reading taking place at home. Results Fifty-one families were enrolled, 8 could not be contacted for follow-up, which left 43 families. Twenty-eight were randomized to book+handout and 15 were randomized to handout alone. On follow-up phone interviews, no significant change in reading was demonstrated regardless of whether a brochure alone was given or a book was given with the brochure. Conclusion Literacy promotion in the ED was not associated with any measurable improvement in parent-child reading. This could mean that the ED is not an effective place to promote literacy or confounding factors in this study are responsible for failing to demonstrate a measurable benefit.

The term pesticide is an all-inclusive word meaning killer of pests (the ending “cide” comes from the Latin “cida”, meaning killer). Pesticides are legally classed as economic poisons and are defined as any substance used for controlling, preventing, destroying, repelling, or mitigating any pest. According to this classification, many chemicals such as attractants, repellents, chemosterilants, hormonal agents, etc., are also designated as pesticides, although from a toxicological viewpoint they may not be directly involved in killing the pest (Table 2.1). Recently, terms like agrochemicals or bioregulators have been proposed to describe pesticides. The main classes of pesticides are shown in Table 2.2.

There are several ways of administering a chemical to an insect. A commonly employed method is topical application, where the insecticide is dissolved in a relatively nontoxic solvent, such as acetone, and small, measured droplets are applied at a chosen location on the body surface. Topical application as is practiced today was made possible by the invention of the micrometer-driven syringe (Trevan 1922) and the use of continuous carbon dioxide anesthesia (Williams 1946). The advantages of this method are: 1. The high degree of precision and reproducibility that can be attained. 2. The large number of tests that can be performed in a relatively short time. 3. The small number of insects (10-20) required per replication. 4. The simple and inexpensive equipment needed. 5. The very small amount of chemicals and solvents used. 6. The fact that the LD50 values obtained for any species are reasonably constant and reproducible from laboratory to laboratory, provided that identical conditions of testing are maintained.

A 72-year-old man was admitted to the emergency department with a diagnosis of inferior myocardial infarction. During intervention with heparin, ventricular fibrillation suddenly occurred. Twelve minutes after resuscitation he was successfully defibrillated with cardiac massage and defibrillation therapy. His respiratory condition progressively worsened and the …

Twenty-six patients with orbital fractures diagnosed with plain radiography and computed tomography were examined with surface coil magnetic resonance (MR) imaging. Fifteen patients had blow-out fractures, and 11 had maxillofacial complex fractures. In all patients with blow-out fractures, the location of the fracture was precisely indicated by the presence of prolapsed orbital fat. Incarceration of the extraocular muscle or orbital fat was correctly diagnosed with MR imaging, which was less sensitive in depicting maxillofacial fractures but was useful in assessment of soft-tissue involvement. Postoperative follow-up MR studies provided valuable information about the cause of motility impairment. While T1-weighted images are useful for the detection of the fracture site, both T1- and T2-weighted images are usually necessary for evaluating soft-tissue lesions. The results of this study indicate that surface coil MR imaging is an important adjunct procedure in the diagnosis and treatment of orbital fractures.

A new murine malignant fibrous histiocytoma (MFH) cell line was established from a 4-hydroxyaminoquinoline 1-oxide-induced MFH. This cell line was followed by a contiguous sheet, and a confluent monolayer was established after 12 days incubation. These cells could be serially transplanted into the subcutaneous tissue of mice, the success rate becoming 100% after the 9th passage. Transplanted tumors demonstrated rapid growth and displayed a high potential for metastasis to the lung after the 16th passage. And a 100% lung metastasis rate was observed for MFH cells after the 20th passage. Histologically, these metastatic tumors retained features of the primary tumor.

Various utility-interactive photovoltaic power conditioning systems have been reported. In general, it could be said that such photovoltaic power conditioning systems have been approaching the ideal, i.e. high efficiency, high performance etc. However, the system cost including that for power converters and solar cells still prevents widespread application. A simple utility-interactive photovoltaic power conditioning system with a forward converter and an innovative lossless snubber circuit are proposed. They are easy to utilise and complement each other. The system operation is confirmed by simulation analysis and experiment.

Although a large number of studies have been made on a theory of scattering, no studies have been attempted to evaluate the scattered sound fields in a concert hall. This paper will show an evaluation method of sound fields that involve scattered reflection by a circular‐columns array installed in front of both side walls. Measurements were performed by use of a 1/10 scale model of the concert hall. Here, scattered sound fields are evaluated by four acoustic factors (SPL, DT1, Tsub; IACC, and in addition WIACC and tauIACC). It is found that the IACC and Dt1 of the sound fields of the concert hall are improved with use of the circular columns array.

Instrumented Charpy impact test has been widely used as a simple method for semi-empirically evaluating material impact toughness. The authors have developed a new instrumented Charpy impact testing system, which is called CAI (Computer Aided instrumented Charpy Impact testing) system. Using the CAI system, dynamic fracture toughness parameters such as Kd, Jd, Tmat, and various absorbed energies can be obtained from the load-deflection curve of a single precracked specimen for both ductile and brittle materials. It has been already put into practical use in Japan. This paper introduces the details of the toughness evaluation procedures in the CAI system.

Degenerative change at the end plate of the discovertebral joint was studied in the elderly adult by correlating the histologic and radiographic findings. Undecalcified ground sections were made from 21 autopsied lumbar spines that demonstrated no evidence of disease except age-related osteoporosis. Histologic examination showed that the cartilaginous end plates were degenerated to various extents and were replaced by subchondral bone proliferation (endochondral bone formation) in the direction of the joint space. In advanced cases, this histologic finding was reflected in radiographs as a subchondral sclerotic zone protruding toward the disk space. The degree of end-plate change was positively correlated with disk-space narrowing and the vacuum phenomenon (degeneration of the nucleus pulposus) but not with osteoporosis and vertebral compression. Anatomically and functionally, this may be the most common form of degeneration at the discovertebral joint end plate. Further study will be necessary to clarify the process.

A 53-year-old man with retinitis pigmentosa, who had two years' complaints of general malaise and muscle weakness, noticed occasional attacks of the cramps of the lower legs about three months prior to admission. At that time, hypocalcemia (7.6 mg/dl) and hyperphosphatemia (5.2 mg/dl) were pointed out. On admission, serum potassium was high-normal or high (4.4 - 4.9 mEq/l). Endocrinological studies revealed the findings of pseudohypoparathyroidism (PHP) type II, including a normal urinary cyclic AMP but blunted phosphaturic response to synthetic human parathyroid hormone (PTH), a high level of serum amino-terminal fragment of PTH with a low level of serum calcium and its ionized form, and a high-normal level of nephrogenous cyclic AMP. This patient also had selective hypoaldosteronism, as shown by intermittent hyperkalemia, low plasma and urinary levels of aldosterone and normal glucocorticoid levels. Plasma renin activity was normal but responded to a greater extent to furosemide plus upright posture. Plasma aldosterone was low and responded poorly to furosemide plus upright posture and graded angiotensin II infusions. The possible explanations for the association of PHP type II and selective hypoaldosteronism in this patient with retinitis pigmentosa are discussed.

A low-permittivity two-level interconnection process is presented. The key features of this process are the use of a low dielectric constant SiBN interlayer and the adoption of planarization using a two-stage etch-back process. The SiBN film is characterized from the standpoint of its device applications. The two-level interconnection process flow is described in detail. The effect of the SiBN interlayer in reducing the second wiring capacitance is compared to that of a conventional silicon nitride interlayer. This is demonstrated by fabricating a 33-stage ECL ring oscillator and a 2.1 kG macrocell array LSI. >

Magnetic resonance imaging of acute spinal cord injury is described. The traumatized cord segment was clearly shown as a hyperintensity in a T2-weighted image whereas it appeared as an isointensity in a moderately T1-weighted image. This different sensitivity may result from parenchymal hemorrhagic tissue and edematous changes due to direct trauma. Hyperintense tissue was also seen in the retro-pharyngeal and -tracheal spaces.

A 37-year-old woman with postoperative hypoparathyroidism had hypertension, and elevated plasma renin activity (PRA) and subsequent hyperaldosteronism during a two-month hypercalcemic period caused by vitamin D and excessive calcium supplements. The hypertension with elevated PRA, however, was resistant to the angiotensin II (AII) analog [Sar1, Ile8] ALL. PRA further increased and plasma aldosterone decreased in response to the [Sar1, Ile8] ALL. When the patient became normocalcemic, normotensive and normoreninemic, calcium gluconate (5 mg calcium/kg/h) was infused for one hour. The calcium infusion reproduced hypercalcemic hypertension mediated by an increase in total peripheral resistance. These observations suggest that the hypertension observed while taking vitamin D and excessive calcium supplements may be caused by a direct effect of calcium on peripheral blood vessels and the renin-angiotensin system may play a negligible role.

Aldosterone responsiveness to angiotensin II (A II) was evaluated in 65 diabetic patients with and without various diabetic complications versus 38 age-matched non-diabetic subjects. Plasma aldosterone (PA), together with plasma renin activity (PRA), was low and responded poorly to furosemide (80 mg, orally) plus upright posture (4 hours) stimulation in diabetic patients. When the PA response to stimulation relative to PRA response was estimated from the ratio of PA increase to PRA increase after stimulation (delta PA/delta PRA), the 38 non-diabetic subjects had ratios more than 3.0. Of the 65 diabetic patients, 48 had normal delta PA/delta PRA ratios (more than 3.0) and 17 had low delta PA/delta PRA ratios (less than 2.9). Graded A II infusions (1, 2, and 4 ng/kg/min each for 30 min) were performed under a low sodium intake (sodium, 120 mEq/day) in 25 of the 65 diabetic patients, whose delta PA/delta PRA ratios were normal in 15 and low in 10, and in 16 non-diabetic subjects. The PA responses to the graded A II infusions in the normal delta PA/delta PRA diabetic patients were similar to those in the non-diabetic subjects. However, the PA responses to the graded A II infusions in the low delta PA/delta PRA diabetic patients were significantly lower. It is concluded that, although the majority of diabetic patients have normal aldosterone responsiveness to A II, some diabetic patients have blunted aldosterone responsiveness to A II probably attributable to the abnormality of the adrenal cortex in addition to the impaired renin secretion.

A 46-year-old woman with hypertension, normokalemia, suppressed renin, normal catecholamines, and a left adrenal mass on the CT scan was found to have excessive 18-hydroxycorticosterone (18-OHB) and normal aldosterone levels in plasma, both of which responded poorly to sodium restriction and angiotension II, and supranormally to ACTH. Plasma 18-hydroxydeoxycorticosterone (18-OHDOC) was normal. After adrenalectomy, amelioration from hypertension occurred with a reduction in plasma 18-OHB and aldosterone. The plasma 18-OHDOC remained normal. The adrenal tumor was histologically an adenoma, containing a large amount of 18-OHB and a small amount of aldosterone. Thus, the present adenoma seems to be a variant of aldosteronomas.