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Objectives We sought to assess angiographic, echocardiographic and hemodynamic grading of paravalvular leakage (PVL) after transcatheter aortic valve implantation (TAVI) with respect to prediction of 1-year mortality. Background Meaningful criteria for the severity of PVL are needed to allow intraprocedural guidance and patient management after TAVI. Methods We pooled the prospective TAVI databases of 2 German centers. During TAVI, PVL was assessed angiographically and by the aortic regurgitation index (ARI). ARI was calculated as ratio of the gradient between diastolic blood pressure and left ventricular end-diastolic pressure to systolic blood pressure times hundred. In addition, we performed transthoracic echocardiography before discharge. Results A total of 723 patients undergoing TAVI with self-expandable (20.9%) or balloon-expandable (79.1%) valves were included. Grades of PVL as assessed during the procedure by angiography or ARI (below the previously defined cut-off of 25) did not show a significant association with 1-year mortality (P = 0.312 and 0.776, respectively). One-year mortality was 15.7% (39/249) in patienths with an ARI

Although hypoglycaemia is a serious risk of intensive insulin therapy, studies on the accuracy of devices for self-monitoring of blood glucose (SMBG) include only a few values below 100 mg/dl. This study evaluated five SMBG devices in the normal range of blood glucose. In three separate series, capillary blood was taken from 207, 214 and 49 healthy subjects and was analysed with the SMBG devices and a laboratory method. Mean (± standard deviation) blood glucose values were 86 ± 13 mg/dl, 83 ± 12 mg/dl and 90 ± 16 in series 1-3. All measurements with SMBG devices differed significantly from the laboratory method. The relative deviation from the laboratory method was 5.5% (2.4-10.5%, median and interquartile range) for Accutrend®, 7.1% (3.6-12.6%) for Precision QID®, 7.5% (3.7-13.7%) for Accu-Chek III®, 14.1% (6.2-22.2%) for Companion 2® and 15.2% (10.3-21.3%) for One Touch II® (p < 0.05). In conclusion, this study shows important differences in the accuracy of five SMBG devices in the normoglycaemic range. Accutrend® and to a lesser degree - Accu-Chek III® and Precision QID® obtained better results and can be recommended for SMBG in patients treated with intensive insulin therapy.

Stacked layer sequences of InP-based HBT and HEMT are of interest for today's (OC-768) and tomorrows (OC-3072, 100 Gbit Ethernet) communication standards. The better low noise performance of the HEMT can be combined with the driver capability of the HBT while also a PIN-photodiode can be provided by the HBT base-collector-diode. However this results in a complex procedure for MOVPE growth process development. For a reliable fabrication of complex radio frequency (opto-)electronic circuit applications a quantitative InP process technology control is necessary starting at the level of device epilayer stacks. In this report the detailed characterization of stacked InP/(InGa)As:C HBT and InP/(InGa)As HEMT layer sequences is carried out by non-destructive X-ray analysis. Based on X-ray measurements in 004- and 002-reflection a detailed analysis of complex device layer stacks is purposed. As a result, an automatic calculation of layer parameters, e.g. thickness and composition is possible, reducing the turn-around time for the statistical process control (SPC).

InP-based high electron mobility transistors (HEMTs) are preferable for 40 GHz applications and beyond due to their low noise figure and the achievable high frequencies. We will report on the MOVPE growth of the required epitaxial InAlAs layers using the liquid precursors tertiarybutylarsine (TBAs) and ditertiarybutylsilane (DitBuSi). The Si, O and C concentrations of the InAlAs as function of the growth conditions will be discussed and it was observed that DitBuSi getters oxygen species and is the main unintentional carbon source for Si–InAlAs. Fabricated HEMTs show maximum oscillation frequencies f max of 210 GHz. Further data on material characteristics, uniformity and device performance will be discussed.

Quantum-effect devices utilizing resonant tunneling are promising candidates for future nano-scale integration. Originating from the technological progress of semiconductor technology, circuit architectures with reduced complexity are investigated by exploiting the negative-differential resistance of resonant tunneling devices. In this paper a resonant tunneling device threshold logic family based on the Monostable-Bistable Transition Logic Element (MOBILE) is proposed and applied to different parallel adder designs, such as ripple carry and binary carry lookahead adders. The basic device is a resonant tunneling transistor (RTT) composed of a resonant tunneling diode monolithically integrated on the drain contact layer of a heterostructure field effect transistor. On the circuit level the key components are a programmable NAND/NOR logic gate, threshold logic gates, and parallel counters. The special properties of MOBILE logic gates are considered by a bit-level pipelined circuit style. Experimental results are presented for the NAND/NOR logic gate.

The cure rate of patients with germ cell cancer of the testis has considerably improved since the introduction of cisplatin based chemotherapy. Because these patients are in their reproductive years and because some of them will be infertile after treatment, the effects of cytotoxic treatment on gonadal function are investigated by hormonal evaluations.In a transversal trial, luteinizing hormone, follicle-stimulating hormone and testosterone were determined radioimmunologically in serum samples of 232 patients with germ cell tumors after unilateral orchiectomy (patient age 18 to 64 years) up to 153 months after chemotherapy. Additionally, 51 of these patients were investigated in a longitudinal trial before and up to 5 years after chemotherapy. All patients received at least 2 courses of different cisplatin based chemotherapy regimens: cisplatin/vinblastine/bleomycin, cisplatin/vinblastine/bleomycin/ifosfamide, cisplatin/etoposide/bleomycin, cisplatin/vinblastine/bleomycin/ifosfamide/etoposide. Additionally, 11 patients with germ cell tumors (age 22 to 38 years, stage I) were investigated within the first year after orchiectomy and retroperitoneal lymphadenectomy but without chemotherapy.In the transversal trial, 24 of 73 patients investigated during the first year after chemotherapy showed elevated luteinizing hormone concentrations, 5 had subnormal serum testosterone and 65 had elevated serum follicle-stimulating hormone, reflecting spermatogenesis deficits. In 28 patients studied longer than 8 years after chemotherapy (median followup 8.5 years, range 8.0 to 12.6), luteinizing hormone increased after chemotherapy and 60 months after treatment, and follicle-stimulating hormone was elevated in 1 patient, follicle-stimulating hormone was increased in 18 and testosterone was subnormal in 1. Patients without chemotherapy treatment showed gonadotropin and testosterone within normal range and 3 patients had elevated serum follicle-stimulating hormone. In the longitudinal study, mean serum luteinizing hormone plus or minus standard deviation (3.45 +/- 0.05 IU/l.), follicle-stimulating hormone (7.79 +/- 0.13 IU/l.) and testosterone (18.6 +/- 0.17 nmol./l.) were within the normal range before chemotherapy; serum follicle-stimulating hormone was still significantly elevated (16.9 +/- 0.71 IU/l., 19 cases, p0.001). Mean luteinizing hormone and testosterone levels were within the normal range, but 60 months after therapy the testosterone-to-luteinizing hormone ratio was still lower than before treatment (p0.05).In patients with germ cell tumors, a compensated insufficiency of the function of the Leydig cells was still observed up to 60 months after chemotherapy. Of these patients 68% showed elevated follicle-stimulating hormone levels, which reflected a functional insufficiency of the Sertoli cells with impaired spermatogenesis. This study shows that impairment of germinative functions is more severe and protracted than the impairment of the endocrine functions.

Intermixing of an (InAs)n/(GaAs)m short period strained layer superlattice (SPSSL) is analyzed. Lattice matched (n ≈ mm) and indium rich (n > m) superlattices have been prepared by molecular beam epitaxy in order to provide a ternary InxGa1 − xAs channel in InP-HFET with a reduced alloy scattering as theoretically predicted. For the optimization the interface intermixing of highly strained heterostructures was investigated using high-resolution double-crystal X-ray diffractometry combined with computer simulations. A method of modelling imperfections in semiconductor heterostructures was introduced to perform the fit between the simulated and measured data in an objective manner. The key steps of this method are (i) the sensitivity analysis of experimental diffraction curve details with respect to imperfections, and (ii) the development of objective error criteria. The result of the modelling process enables a quantitative and objective determination of the intermixing at InAs/GaAs interfaces in relation to the molecular beam epitaxy (MBE) growth parameters.

Although clinical and experimental evidence favours early enteral feeding in the critically injured, provision of such enteral feeds can be difficult. Gastric feeds are often not tolerated and may lead to aspiration. An intolerance of gastric feeds leads to a cumulative energy and protein deficit and may result in the initiation of expensive parenteral nutrition (TPN). An alternative and under-utilized technique to ensure enteral access in trauma victims is the insertion of a transpyloric (nasojejunal) feeding tube during emergent laparotomy. We have employed this method of enteral access with success. In the following report, we describe this technique, provide an illustrative case with a cost comparison between nasojejunal feeds and TPN, present the rationale for such a mode of enteral access and outline the indications and contraindications. Enteral access by the intra-operative insertion of a transpyloric feeding tube allows immediate/early enteral feeding that is easy, safe, reliable and inexpensive.

Die Serumkonzentration der neuronspezifischen Enolase (NSE) wurde bei 126 Patienten mit malignem Melanom (MM, Stadium I / II: n=80; Stadium II:n = 23; Stadium IV:n = 23) radioimmunologisch bestimmt. Erhohte NSE-Konzentrationen (Schwellenwert: > 12, 5 μ/L) fanden sich bei 12, 5 % der Patienten mit MM im Stadium I / II, 13. 0 % im Stadium II und bei 39, 1 % im Stadium IV. In der Langzeit-Verlaufskontrolle bei 20 Patienten im Stadium II / K zeigte die NSE-Serumkonzentration eine Ubereinstimmung mit der Tumoraktivitat. Bei 6 Patienten zeigte sich unter der Therapie ein Abfall erhohter NSE-Werte als Zeichen einer Tumorregression. Das Ausbleiben eines signifikanten Abfalls oder gar ein Anstieg wies in 86, 7 % (13/15) der Falle auf eine Tumorprogression hin. Ein signifikanter Anstieg von NSE wurde bei 6 Patienten prafinal gesehen. Daraus last sich folgern, das NSE fur die Primardiagnostik des malignen Melanoms aufgrund der niedrigen Sensitivitat als Tumormarker ungeeignet ist; jedoch erscheint eine NSE-Bestimmung bei Patienten mit malignem Melanom im Rahmen einer Verlaufskontrolle sinnvoll.

Opioids have an inhibitory effect on sexual functions in both animals and humans. Twenty patients with idiopathic, nonvascular, nonneurogenic erectile dysfunction were treated with the opiate receptor antagonist naltrexone in a randomized, placebo-controlled, double-blind study for 8 weeks. Libido and frequency of sexual intercourse were not significantly altered, but early-morning erections increased significantly under naltrexone therapy. This response was not related to levels of androgens or gonadotropins, neither was it dose dependent. There was no change in any of the measured parameters under placebo. Further clinical studies with the substance should be conducted to evaluate its possible role in the oral treatment of male impotence.

This sensor-based approach for registration and stacking of electronic substrate sublaminates replaces pin-in-slot methods, yet does not require accurate automation equipment. Tests of a pilot workcell for this approach showed that the contact holes were consistently aligned to 2.5 /spl mu/m (3/spl sigma/), more than ten times better than the traditional mechanical method.

In vitro studies have shown that the Sertoli cell is the primary source of inhibin in the male. We measured immunoreactive inhibin with a new two-site immunoenzymatic assay in the plasma of 92 men: 40 normal men, 7 patients with germinal cell cancer after unilateral orchidectomy and 45 patients with the same disease following unilateral orchidectomy and subsequent chemotherapy based on cisplatin. Normal men had inhibin levels of 1.77±0.09 U/l × 10−3 (mean±sem). Seven patients after unilateral orchidectomy had inhibin concentrations within the lower normal range (1.23±0.22 U/l × 10−3). Forty-five patients were investigated in a cross-sectional study up to 102 months after completion of chemotherapy. Inhibin levels were within the normal range in 25 patients (1.76±0.114 U/l × 10−3); 18 patients had significantly lower inhibin levels (0.48±0.05 U/l × 10−3, p−3). The proportion of patients with normal and subnormal inhibin was not dependent on the time that elapsed after completion of chemotherapy or on the chemotherapy combination. There was no correlation between immunoreactive plasma inhibin and LH, FSH, testosterone or sperm count. The decrease in inhibin concentrations after chemotherapy may indicate long-term damage to Sertoli cells in some of the patients.

A 1550-nm coherent receiver with a LiNbO3 optical hybrid and balanced photoreceivers integrated in a single compact package is reported. Frequency response of the integrated receiver and bit-error-rate measurements of optical PSK signals are described.

High-frequency vertical PIN detectors with highly p-type doped InGaAs basis layer were investigated. Reducing the PIN area and series resistance together with the thickness of the undoped drift region results in f3dB corner frequencies of up to 120 GHz. In addition, the vertical PIN concept reveals several advantages compared to waveguide PINs like the possibility to build two dimensional detector arrays and it is perfectly suited for monolithically integrated opto-electronic receiver ICs (OEIC). Further PIN and OEIC results will be presented.

Carbon doped InP/(InGa)As Heterostructure Bipolar Transistors (HBT) are of interest for today's (OC-768) and tomorrow's (OC-3072, 100 Gbit Ethernet, UMTS) communication standards. For a reliable fabrication of these complex radio frequency (opto-)electronic circuits, a quantitative InP process technology control is necessary starting at the level of device epi-layer stacks. In this paper the quantitative characterization of an InP/(InGa)As:C HBT is carried out by non-destructive X-ray analysis. Based on X-ray measurements in 004- and 002-reflection, a detailed analysis of complex device layer stacks is purposed. As a result, an automatic calculation of layer parameters, e.g. thickness and composition is possible, reducing the turnaround time for statistical process control (SPC).

An experimental system that can accurately align and place SMDs (surface mount devices) on a printed circuit board is described. Features of the system are fine positioning and endpoint sensing after an IBM 7576 robot coarsely aligns the SMD to its target. Fine positioning is done using a customer-designed micropositioning device. The endpoint sensor is a single camera vision system that by image analysis determines the alignment error of the SMD to the board. System performance was evaluated by placing SMDs of 100 leads with 25 mil lead spacing on a board. The alignment error is less than 0.5 mil and 0.015 degrees , independent of feeder and board position error or robot repeatability. The average cycle time is less than 10 s. >

Special-purpose sensors and hybrid mechanical systems have been developed to assemble advanced electronic circuits. State-of-the-art robot systems that are used for electronic assembly and accuracy requirements for the developing surface mount technology are reviewed, showing the need for improved robot positioning capability. Examples of laboratory experiments that demonstrated successful precision assembly or testing using an ordinary robot, a micropositioner, and an optical sensing system are given. These involve fiber-optic sensing, machine-vision endpoint sensing, and hybrid tactic-vision endpoint sensing. >

For simulation of digital circuits realized in Direct Coupled FET Logic (DCFL) using depletion-type as well as enhancement-type Heterostructure-Field Effect Transistors (HFET) a consistent model that is able to describe both types of transistors is necessary. The developed analytical PSPICE model takes into account all relevant intrinsic and parasitic effects. This model can be used for dc- as well as rf-simulations and is scaleable with respect to gate-width as well as gate-length.

Assembly accuracies of 0.05-0.1 mm, needed for electronic product manufacture, are attainable with current automated manufacturing equipment. Aggressive electronic system designs will require manufacturing accuracies in the range of 0.005-0.01 mm. A system and strategy is described here to fabricate circuit boards requiring alignment accuracies of 7.5 /spl mu/m using existing automation equipment with enhancements and typical manufacturing line fixtures. The system, configured as a pilot workcell, consisted of an IBM 7576 coarse positioning robot, a fine positioning manipulator, an optical sensing system and a unique bracing method to reduce environmental disturbances. The strategy was to use a coarse/fine placement technique with sensing to align, stack and bond individual test laminates with patterns of 100 /spl mu/m holes. The results showed that pairs of holes were consistently aligned to 2-5 /spl mu/m which surpasses the 7.5 /spl mu/m manufacturing requirement. >

This paper describes the InP-based HFET technology for the implementation of high bitrate logic gates. A novel logic gate configuration is presented based on depletion mode HFETs (DHFET) using a nonlinear negative feedback (NNFB) for optimized high speed operation. The NNFB increases the switching speed of the gates while reducing the logic HIGH output level. The functionality of this logic design approach is demonstrated in InP with an 11-stage inverter chain and an output buffer. The realization of a ring oscillator and an edge-triggered D-flip-flop are currently in progress.

We have developed a new concept for an optoelectronic frontend receiver at 0.85 /spl mu/m wavelength. A GaAs-PIN photodiode is coupled to a Permeable Junction Base Transistor (PJBT). The PJBT is a vertical Junction Field Effect Transistor with a homoepitaxial, heavily p-doped gate whose n-doped GaAs channel is selectively grown. Its layer structure incorporates two p-i-n doped layer structures, so it fits ideally to an integration with a PIN photodiode. The fabrication of the integration is described and results of the single devices, both DC and RF measurements, are presented. The performance of the first integrated receiver show the usefulness of this concept for Optoelectronic Integrated Circuits (OEIC) at bitrates of more than 1 Gbit/s.

Planar linear motors, e.g. Sawyer motors, operate in an open-loop stepping-manner. This mode of operation makes them: 1) susceptible to loss of steps, 2) unable to reject external disturbances, 3) unable to provide controlled forces, and 4) unable to provide high stiffness. These limitations, in turn, restrict their usefulness in a wide range of robotic applications. Suitable position sensing and control technology, when added to such motors, can to a large degree eliminate these problems. In this paper we present two new sensor technologies for planar motor systems: one uses an AC magnetic technique, the other uses an optical fluorescence technique. The magnetic sensor has achieved 1 /spl mu/m position resolution and is compact and easy to fabricate. The optical fluorescence sensor has the advantage of complete insensitivity to nearby motor fields. Either technology has the potential to greatly improve future robotic systems that are based on planar linear motors.

A pseudo dynamic logic family is developed on InP-substrates based on the MOBILE concept. The conventional HFET as input terminal is replaced by a monolithically integrated series combination of a HBT and a RTD forming a RTBT. This combination enables a logic function defined by the RTD area only. The HBT provides a robust enhancement type operation, although for full level compatibility a buffer inverter is still necessary. A novel distributed clocking scheme is developed. The feasibility of this logic concept is experimentally verified and an OR gate is discussed in detail.

The technology of resonant tunneling device logic circuits using a modified monostable-bistable transition logic element (MOBILE) is presented. A nanoelectronic circuit architecture based on an improved MOBILE threshold logic gate is used. The improvements of the basic MOBILE are motivated from the circuit design point of view, and comprise a separate power supply and clock, a dual threshold voltage process, and on-chip clock delay lines. The demonstrator circuit is a pipelined one-bit full adder on an InP-substrate. SPICE simulations are carried-out in order to prove the functionality and to evaluate tolerable clock and supply voltage fluctuations in comparison to device parameter feasibility.

This paper presents the performance of an 11-stage ring oscillator for high speed digital circuits using a gate configuration with nonlinear negative feedback (NNFB). An additional transistor is introduced into the switching path of buffered FET logic (BFL) gate to reduce the logic HIGH level, thus limiting the logic swing. As the result, the switching speed of the circuits is improved by about 50% compared to conventional BFL gates, while maintaining almost the same power consumption. The performance of this logic design approach is demonstrated by an e-beam written 11-stage ring-oscillator using InP-based depletion-type heterostructure field effect transistors (DHFET). The oscillation frequency is 3.36 GHz corresponding to a delay time of 13.5 ps per gate.

Negative-differential resistance devices, i.e. Resonant Tunneling Diodes (RTD) have recently enabled a substantial improvement in low-power memories and high-speed logic gates. For logic circuits two series connected RTDs are monolithically integrated with parallel HFET input branches building the monostable-bistable transition logic element (MOBILE). In this paper we report on drastic improvements of the MOBILE concept addressing the major restrictions: trade-off between output driving capability, number of inputs and additional current for the parallel input branches, critical design criteria for two independent technologies: HFET (threshold voltage, lateral current density) and RTD (device area, vertical current density).

We evaluate the use of pretreatment follicle-stimulating hormone (FSH) in patients with germ cell tumors as a prognostic serum marker of spermatogenesis after standard treatment. Additionally, Leydig cell function was investigated by estimation of luteinizing hormone (LH) and testosterone (T), and calculation of the T/LH ratio.Serum FSH, LH and T were determined radioimmunologically associated with semen analyses in 20 patients with seminoma (pathological stages IA to IIB) after unilateral orchiectomy before and up to 24 months after infradiaphragmatic radiotherapy. Additionally, hormone analyses were performed in 18 patients with nonseminomatous germ cell tumor (pathological stages IIA to C) before and up to 36 months after standard cisplatin based chemotherapy.Seminoma patients undergoing radiotherapy were divided into 2 groups consisting of 12 patients with normal pretreatment serum FSH and 8 with elevated FSH reflecting spermatogenesis deficits even before treatment. Six months after irradiation a significant increase in FSH (p0.01) associated with a decrease in sperm density was observed in both groups and 24 months after radiotherapy patients with initially normal FSH had significantly lower serum FSH (p0.01) associated with higher sperm density than those with initially elevated FSH (p0.01), indicating less impairment of Sertoli cell function. Comparable results were observed in chemotherapy treated germ cell tumor patients with initially normal (11) and elevated serum FSH (7), respectively, and 36 months after chemotherapy patients with initially normal FSH had significantly lower FSH concentrations than those with initially elevated FSH (p0.01). Compensated impairment of Leydig cell function reflected by a subnormal T/LH ratio was evident before chemotherapy in 16.7% of patients increasing up to 41.2% 36 months after therapy. In contrast, 24 months after radiotherapy only 25% of seminoma patients showed a subnormal ratio reflecting less damage to the Leydig cells caused by irradiation.Pretreatment FSH is a prognostic serum marker of spermatogenesis status of germ cell tumor patients receiving standard radiotherapy or chemotherapy. In contrast to seminoma patients after radiotherapy, impairment of Leydig cell function was evident in germ cell tumor patients after cisplatin based chemotherapy.

An InP-based HFET technology for monolithically integrated high speed digital circuits is described. A novel logic gate configuration is presented based on depletion mode HFETs using a nonlinear negative feedback for high speed operation. A possible implementation of enhancement mode transistors and the promising combination with a low-peak voltage RTD is also presented. A preliminary investigation on manufacturability of RTDs is given. We report on the realisation of RTD/E-HFET on InP as a building block for digital circuits and its applicability to a novel circuit architecture (multiple input threshold logic).

Interface intermixing of highly strained heterostructures was investigated using high-resolution double-crystal X-ray diffractometry combined with computer simulations. A method of modelling imperfections in semiconductor heterostructures was introduced to extract information from simulated and measured data in a fast and objective manner. The key steps of this method are i) the sensitivity analysis of experimental diffraction curves with respect to imperfections, and ii) the development of objective error criteria. The applicability of this method is demonstrated using highly strained [(InAs/GaAs)12/InGaAs]9 superlattices grown by molecular beam epitaxy (MBE) on InP substrates. The result of the modelling process enables a quantitative and objective determination of the intermixing at InAs/GaAs interfaces in relation to the MBE growth parameters which can be transferred to any other laboratory.

An experimental system that can accurately align and place SMDs (surface mount devices) on a PCB (printed circuit board) using a coarse/fine positioning component placement strategy and end-point sensing to measure the alignment error is described. Coarse positioning is done with an IBM 7576 robot, and fine positioning is done using a custom-designed precision micropositioning device attached to the end of the IBM 7576 robot. The end-point sensor is a single-camera vision system that by image analysis determines the alignment error of the SMD to the board. System performance was evaluated by placing SMDs of 100 leads with 0.63-mm (25 mil) lead spacing on a board. An alignment error of less than 12 mu m (0.5 mil) and 0.015 degrees was obtained independent of feeder and board position error or robot repeatability. The average cycle time was less than 10 seconds. >

Adrenoleukodystrophy and its clinical variant adrenomyeloneuropathy (AMN) are disorders due to peroxisomal degradation of very-long-chain fatty acids (VLCFA). Both forms are characterized by CNS involvement and variable involvement of endocrine functions, especially the adrenal cortex. [1] It has been a matter of debate whether adrenocortical insufficiency (Addison's disease) may precede or follow the onset of neurologic symptoms. [2,3] We evaluated the onset of symptoms of adrenocortical insufficiency and of neurologic symptoms using a questionnaire supported by the German ``Informationsnetzwerk Leukodystrophie, Bonn.'' Items of adrenocortical insufficiency were fatigue, hyperpigmentation, nausea, and vomiting and items of neurologic involvement were muscle weakness, spasticity, and sensory disturbances. The questionnaire was returned by 41 male patients, ranging in age from 18 to 59 years …

Studies of the feasibility of custom-interconnected, large-scale integrated circuits required the development of means for converting computer-generated wiring instructions into metallic conductors on a semiconductor wafer. The resulting equipment took two forms. In one, ultraviolet light serves to expose phctoresists on a mechanically translated wafer; the other employs an electron beam. Both systems werae dequate to produce two-mil-wide conductors, but differ in their potefonrt iaacl hieving high production rates or very thin lines.

Large scale integration offers the possibility of very low-cost digital circuits. However, to realize fully the cost potential in LSI, several problems must be solved, one of which is the time and cost involved in preparing, by conventional techniques, masks for LSI chip fabrication. To facilitate mask generation, an artwork generator system has been developed. The system, comprised of a small artwork generator of high capability and a language structure which allows for compact description of chip features, has demonstrated itself capable of substantial savings in mask generation time and cost.

This paper describes a new type of planar thin-film cryotron namely, an in-line cryotron, and compares its advantages to the crossed-film cryotron. This cryotron has its gate and control elements superimposed and parallel, or in-line, whereas the crossed-film device has its gate and control elements crossed at right angles. The gain curve for the in-line cryotron has a region where incremental gains of one to ten may be obtained without a change in the gate-to-control width ratio Wg/Wc whereas large gains are not possible for the crossed-film cryotron without altering the width ratio. Larger gate resistances are possible within the in-line cryotron and calculations are given to show it is feasible to properly terminate low impedance strip transmission lines with characteristic impedances in the range of 0.1 to 1.0 ohms. It is necessary to properly terminate the strip transmission lines commonly used in superconducting circuit fabrication in order to achieve the maximum circuit switching speeds. Other advantages and the disadvantages of the in-line cryton are also discussed.

The purpose of this paper is to direct attention to a symptom that in my experience and in that of my immediate associates is of very frequent occurrence and which has, so far as I know, received little, if any, attention in the literature. Several recent exhaustive papers on the subject of abdominal pain in children do not mention it and a partial search of the literature would lead one to think that others have either not made the same observation or else have failed to consider it as a distinct entity worthy of record. For nearly ten years this symptom has so regularly and so insistently intruded on our attention that it has seemed to me worth while to discuss it on an occasion like this. The symptom to which I refer is that of abdominal pain occurring often to the exclusion of all other subjective symptoms, or, at

The curds that occur in the stools of infants, especially of those fed on cow's-milk, have been the subject of much discussion among pediatricians. A great deal of importance attaches to the solution of the problem of their etiology and nature, because their presence in the stools has always been considered an evidence of an overstepping of the infant's tolerance for the particular food element from which the curds were thought to be derived. The pendulum has swung from the first natural interpretation that they were undigested particles of curdled milk, therefore chiefly protein in origin, to the opposite extreme, if we are to accept the teaching of nearly all the foremost German pediatricians, that the casein takes no part in their formation. From observations that we have made in our clinic at Northwestern University Medical School, and from some experiments that I have made in the past year, I

In our progress upward, whether in religion, in economics or in the science and art of infant feeding, we advance by epochs, and often the gospel of one epoch becomes the heresy of the next, only to become again the gospel in the light of some newer truth. In the first flush of bacteriologic activity, the idea that infantile diarrheas were infectious and that milk carried pathogenic micro-organisms naturally led to sterilization of the baby's milk by heating it. Then scurvy intruded itself, and pasteurization at lower heat, yet high and long enough to destroy pathogenic germs while influencing the milk less, took its place. But pasteurization was still held as only less objectionable, and for the same reasons, than sterilization, and offered serious technical difficulties. There naturally followed a demand for a milk clean and fresh and nearly enough germ free to be safe without heating. By analogy with

We are all familiar with the fact that disturbances of the alimentary tract, such as indigestion, summer complaint, ileocolitis, cholera infantum, etc., are commonly accompanied by more or less profound nervous symptoms that in their totality make up the clinical picture of an intoxication. The babies thus affected are listless, drowsy, stuporous, heavy-eyed, with eyes fixed on vacancy, are hard to rouse and quickly sink back into their stupor, which in severe cases may amount to coma. They look as if under the influence of a drug, as if poisoned or intoxicated or "dopey." We have become so accustomed to thinking that such intoxications, characterized as they are by fever, leucocytosis, psychic depression, collapse and evidences of indigestion or enteritis, must be due to a bacterial toxin that a simpler explanation has escaped us. In a series of papers that will serve as models of profoundly critical and convincing scientific

During the last decade the problem of infant feeding has been a peculiarly interesting one in this country. While European writers are fairly well agreed on fundamental methods, there has grown up a system of infant feeding in this country that in its elaboration is unique. This so-called percentage, or American, system has received such universal and unqualified approval among our pediatricians that it seems almost like heresy to doubt its tenets, and yet an overwhelming mass of evidence has appeared in the last few years that to my mind discredits the fundamental principles of that system. I shall first outline what I believe to be a rational dietary for the first year of life and will then advance briefly some objections to the percentage method. It is important at the start to define the term "healthy" baby, because there is an essential difference between a healthy and a sick

The dynamic operation of the in-line cryotron is tested by performing pulse measurements on individual devices and also by using the device in free-running closed-loop oscillators (similar to shift register). The gain of the device is currently insufficient to permit bit transfer from one stage of the oscillator to the next in less than 25 nsec. This propagation time is slow when compared to the 10-nsec circuit time constant L/R that was designed for each stage. The slower propagation is shown to be associated with the slow transition of resistance from the superconducting to the normal state and also from the normal to the superconducting state. Pulse measurements on the device indicate that the cryotron switching time is dependent upon the magnitude of the applied magnetic field. The times for switching resistance obtained from the pulse measurements are applied to the analysis of the dynamically operating closed-loop register. The maximum oscillating frequency of 5 Mc for a four-stage closed register was predicted by the analysis and is shown to be in good agreement with the experiment. A similar analysis, using the same cryotron limitations, shows the maximum frequency for a two-stage closed-ring register to be essentially the same as that for a four-stage register. Again, this was verified experimentally. The benefits originally projected for the biased in-line cryotron in comparison to the crossed-film devices appear to have been overestimated. The large incremental gains anticipated are not obtainable when operating the device at frequencies of about 107cps or greater. This limitation arises from the requirement of supplying bias at 0.7H c and preferably 0.5H c to allow for a fast turnoff of the device. Consequently, the static gain is not sufficient to provide a large overdrive for a fast turn on for the device. Thermal considerations, state-of-the-art fabrication, and testing procedures are discussed along with projected cryotron improvements that could lead to flip-flop time constants of about 10 nsec.

The rheumatic nodules that receive so much attention from British writers on rheumatism in children are almost universally considered a rare condition with us. In all our textbooks there is a striking uniformity of expression that these nodules are common in England, but are rarely seen in this country. Thus Holt and Howland 1 say: "They are certainly not common in this country, and although we have made it a rule to examine rheumatic patients for them, we have seen them but seldom, and they have been prominent in only eight or ten cases. This has also been the experience of most observers in this country. From published reports, however, they appear to be much more frequent in England." In the 1911 edition of Holt 2 the prominent cases had been placed at "two or three." Koplik 3 says: "The so-called subcutaneous rheumatic nodules are seen in children less frequently

For a number of years my attention has been drawn with increasing frequency to a peculiar lesion of the meatus urinarius occurring only in circumcised male children, and characterized by ulceration, crusting, narrowing of the urinary passage, and nearly always accompanied by painful urination, often with distended bladder, and, occasionally, by hemorrhages. I have been able to find only one reference 1 to it in the literature. While this condition probably is common in occurrence in the experience of all pediatrists, I am inclined to believe that it is more common in this locality and in more recent years than in some other localities and in my own earlier years, and that the manifestations are more severe. My first impression was that this lesion was caused by rubbing against the clothing of the naturally most accessible and most vulnerable portion of the exposed glans, the meatus. This, however, seemed improbable