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This paper describes an approach to achieve good trajectory tracking performance needed in printed circuit board (PCB) assembly by using a joint torque disturbance observer. By observing the difference between the reference torque and the output torque based on a prescribed model, the proposed disturbance observer immediately feeds back the discrepancy to filter off the disturbance. In this way each robot joint becomes linearized and decoupled and a simple PD with feedforward control is sufficient to achieve high accuracy trajectory tracking. A particular advantage in this observer implementation is that only position and velocity signals are required for control purposes. The observer also provides an estimation of external reaction force which is useful in deciding whether a particular threshold level has been exceeded as an indication of jam. This duality in functionality eliminates a force sensor to detect external force. Experiments are carried out on a SCARA robot to verify the accuracy of the overall controller. >

Adaptive filters have often been implemented using the conventional least mean squares (LMS) algorithm due to its inherent simplicity and robustness. However, its poor pipelinability greatly limits its use as a high-performance filter. In this paper, we present a wave-pipelined delayed LMS filter architecture using advanced retiming methods and algorithm modification. In addition to the arbitrarily high-sampling rate that is possible due to the delayed coefficient adaptation algorithm, we retime the signal-flow graph (SFG) of a proposed architecture in order to accommodate wave pipelining of the multiply-and-accumulate (MAC) block. The trade-off for reduced cycle time is an increase in the filter's convergence time. The resulting systolic array implementation is highly pipelined for high-performance and is architecturally scalable because the sample rate is independent of the number of taps.

The medium-level part of a real-time robot vision system involves many subsystems which combine both intensive arithmetic computations and complex decision-making. Moreover, recursive loops typically limit the throughput. Therefore, it is believed that these subsystems can only be efficiently realized within the required throughput specs by developing a BLSI ASIC. This applies also for the regularity detection unit which is the main topic discussed. During the architecture design, several tasks have to be addressed. Starting from the original signal flow graph, the dedicated I/O blocks and the customized, distributed off- and on-chip storage units have been derived. A number of time-multiplexed application-specific data-paths have been defined, optimized towards communication with the memories and towards maximal hardware-sharing within the throughput spec. They exploit the concurrency inherent in the algorithm and are balanced in terms of pipeline sections to increase the clock period achievable. In order to solve the timing bottle-neck in the steering of this complex (partly programmable) data-path organization, a hierarchically partitioned controller is constructed. >

To shorten design time, it is very important to correctly supply the wire load of nets to the synthesis tool before layout. In this paper, a procedure to create wire load models for a specific processing technology and design flow is presented. Also a physical to logical hierarchy mapping procedure is proposed such that the correct wire load model may be applied to drive synthesis before layout. We apply these methodologies to our company's products of 0.6 /spl mu/m technology as illustrations.

surgery (60% in each group), and percentage for whom surgery time was over 180 minutes (63% versus 59%, P=0.51). Diaries were completed by 85% of intervention subjects and 75% of comparison subjects. Prevalence of PON was significantly lower in the intervention group than the comparison group (24% versus 70%, P

Publisher Summary The chapter presents a study on practical considerations in acquiring biological signals from confocal microscope. The chapter presents several potential problems that one has encountered, which either reduced the efficiency of the experiment process or gave rise to erroneous interpretations. In a confocal microscope, the excitation light generated by a laser is focused to a discrete point of the specimen to reduce the wide-view illumination and a pinhole is put in front of the detector to prevent the passage of signals coming from planes other than the confocal section. The development of the lipophilic membrane-permeant acetoxymethyl (AM) ester form of fluorescent indicators provides a nondestructive method of introducing probes into the cytoplasm for various biochemical studies without perforating the cells with micropipettes and injector. Temperature is one of the most important physical parameters that control physiological processes. To mimic the in vivo system, the temperature for experiments is usually set to the body temperature of the host animal, which is normally higher than the room temperature. The chapter discusses water content of dimethyl sulfoxide and efficiency of dye loading.

The preparation of thiolane 1-oxide 10 by photochemically mediated rearrangement of sulfoxide 9 in high yield is described. The efficient construction of quaternary carbon centers underscores the utility of this methodology in organic synthesis. Further manipulation of photoadduct 10 leads to the formation of diverse heterocyclic structures.

Fluorescence microscopic imaging (FMI) is one of the fastest growing and most powerful techniques to study cellular activities in a living single cell. FMI has been widely used to monitor the temporal and spatial changes of many important intracellular messengers such as Ca2+, H+ and cAMP. In the course of our study of cellular responses with confocal scanning fluorescence microscopy, we detected two sources of artifacts which may render experimental observations invalid. First, the water content of the DMSO used could affect the efficiency of loading of the fluorescence indicator into cells and also give rise to spurious fluorescence spots. Secondly, apparently spontaneous temperature-dependent oscillations of BCECF fluorescence and cellular pulsations were recorded in cells which might be misinterpreted as natural rhythmic behavior. These were later shown to be artifacts arising from changes in refractive indices of the immersion oil due to small fluctuations in temperature, which in turn leads to random shifts of the focal plane erroneously manifest as signal oscillations. Based on these observations, certain recommendations for the control and elimination of false images are presented.

The effect of hyperthermia at 43 degrees C on intracellular pH (pHi) in human U-87 MG glioblastoma cells was studied by using the fluorescent probe 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein-pentaacetoxymethyl ester. The presence of Na+/H+ antiporter activity in the cells were demonstrated by the Na(+)-dependent increase in intracellular pH (pHi) after cellular acidification in the absence of HCO3-. Hyperthermia at 43 degrees C caused significant decrease in pHi. The acidification was readily reversible by cooling the cells back down to 37 degrees C. The pHi change was inhibited by the addition of 1 mM amiloride in the incubation medium. Amiloride and hyperthermia exhibited a synergistic effect in suppressing thymidine incorporation into the cells.

Multiple hyperthermia was found to exert an additive antitumor effect when combined with the in vivo production of tumor necrosis factor alpha (TNF-alpha) in mice bearing Ehrlich ascites tumor (EAT). TNF-alpha was produced in EAT-bearing mice by priming the animals with zymosan and subsequently challenging with lipopolysaccharide (LPS). Mice were pretreated with sulindac and D-mannoheptulose to alleviate the toxic side effects of LPS. While the ability of these tumor-bearing mice to produce TNF-alpha remained unchanged under hyperthermia, the EAT cell number was suppressed in the combined-treatment group compared with groups treated with TNF-alpha or hyperthermia alone. In the same comparison, the life span of EAT-bearing mice in the combined-treatment group was prolonged.

Three groups of Lymnaea viridis snails were infected with one, three or five Fasciola hepatica miracidia, and their metacercarial production was observed. In all groups cercarial shedding commenced in some snails as early as day 27 post-infection. The duration and pattern of cercarial shedding varied from snail to snail in each group. Snails infected with three or five miracidia produced more metacercariae than those infected with a single miracidium. The overall metacercarial production was influenced by the temperature at which the snails were kept during infection.

Waglerin-I, a lethal toxin isolated from the venom of Trimeresurus wagleri, consists of 22 amino acid residues with a proline-rich sequence. In the present study, we investigated the cause of death and the possible site of action of this toxin. In anesthetized mice, i.v. administration of waglerin-I at 0.5 microgram/g produced respiratory failure within 5 min. The blood pressure could be maintained by the application of artificial respiration immediately after respiratory arrest. Waglerin-I at 4 microM reversibly blocked the indirect twitch of the mouse phrenic nerve-hemidiaphragm preparation, but had no effect on the direct twitch. It is concluded that respiratory failure, resulting from neuromuscular block, is the primary cause of death due to waglerin-I in mice. In contrast to the results obtained in mice, in anesthetized rats no toxic effects on respiration and blood pressure were observed except for a transient hypotension up to 10 micrograms/g (i.v.). In accordance with the in vivo experiments, waglerin-I at concentrations up to 40 microM did not block the indirect twitch of the rat diaphragm. It thus appears that rats are resistant to the toxic effects of waglerin-I.

The double perovskite Ba2Fe1+xMo1−xO6 ( x=0.0, 1 9 , 2 9 and 1 3 ) oxides have been prepared by different methods in order to investigate their structure, magnetism, and transport behaviors. All compounds synthesized by oxides and carbonates in H2/Ar atmosphere appear a cubic structure without secondary phase. The compounds prepared without Mo metal show high conductivity (ρ∼10 −3 Ω-cm ) with metallic type, ferrimagnetic T C ∼340 K and μeff∼3μB at 77 K . In contrast to that of the compounds prepared without Mo metal, the properties of another samples prepared with Mo metal is found to depend obviously upon the x of the Ba2Fe1+xMo1−xO6 compounds.

The histologic and ultrastructural features of a time sequence study of the development, evolution, and healing of acetic acid-induced experimental duodenal ulcer are presented. Duodenal ulcers produced by serosal application of acetic acid featured microvascular injury with progressive disintegration of the tips of the mucosal villi and subtotal necrosis of the duodenal wall. At 3 days ulcers transformed into a chronic state with regenerating epithelium originating from the crypts of the intact bordering mucosa extending toward the center of the ulcers. By 21 days healed ulcers were covered by distorted duodenal surface mucosa. We conclude that this reproducible and standardized model of duodenal ulcer features vascular injury as the earliest microscopic event, that ischemic necrosis leads to ulceration, and that the chronic phase bears morphologic resemblance to human duodenal ulcer.

The developmental expression of the individual components of the insulin-like growth factor (IGF) system in pigs was examined. Serum IGF-I and IGF-binding protein-3 (IGFBP-3) levels were low during fetal life and increased during postnatal development. Levels of mRNAs encoding these proteins were not greater for liver than for nonhepatic tissues (skeletal muscle, lung, kidney) and did not increase during the postnatal period, whereas hepatic growth hormone (GH) receptor mRNA expression was increased postnatally. Serum IGF-II levels exceeded IGF-I levels at all developmental stages examined and both exhibited postnatal increases. IGF-II mRNA abundance, in contrast, was high in the fetal tissues with the exception of lung and declined during the perinatal transition. Hepatic IGFBP-2 mRNA and serum IGFBP-2 levels increased during the latter half of gestation and then declined postnatally. The levels in muscle and liver of type I IGF receptors and the corresponding mRNAs also exhibited postnatal decreases. The discordance of changes in hepatic IGF-I and IGF-II mRNA abundance with serum IGF levels during the postnatal period does not support the concept that liver is the primary endocrine source of IGFs in the young pig. The postnatal increases in serum IGF levels may reflect decreased plasma clearance rates of these peptides which may be related to the transition in IGFBP type from IGFBP-2 to IGFBP-3 in blood and the reduced tissue expression of IGF receptors.

Helicobacter pylori has been implicated in the genesis of human gastritis, dyspepsia, and peptic ulcers. However, its influence in the quality of experimental gastric ulcer healing has not been previously investigated. Standardized gastric fundic ulcers were produced in 50 male Sprague-Dawley rats (150–200 g) by a 4 mm in diameter focal, serosal application of 100% acetic acid. Thirty rats were administered 2 ml H. pylori suspension (urease producing, ATCC 43504) in normal saline (10 8 CFU/ml) 2×/day for 7 days. Twenty rats (controls) received 2 ml normal saline 2×/day for 7 days. Gastric ulcer surface area was measured under a dissecting microscope and mucosal specimens were obtained for qualitative and quantitative histology. No gross or microscopic duodenal abnormalities were identified at sacrifice. Ninety percent of control rats showed grossly and microscopically entirely healed ulcers. The remaining 10% showed partially reepithelialized ulcers (area, 0.78 to 1.77 mm 2 ; mean, 1.27 ± 0.7 mm 2 ). The grossly “healed” mucosa demonstrated marked dilatation of gastric glands lined with mature surface epithelial cells. Parietal cells were scanty (5–10% of all cells). One hundred percent of the H. pylori -exposed rats showed persistence of chronic active ulcers (area, 1.76 to 19.63 mm 2 ; mean, 8.95 ± 6.15 mm 2 ). The ulcer beds were infiltrated by acute and chronic inflammatory cells, abundant fibroblasts, and capillary networks. The raised ulcer borders were characterized by dilated glands lined by mature surface epithelial cells. Various special stains demonstrated the presence of H. pylori in the surface mucus and within the crypts. We conclude that (1) H. pylori delays healing of experimental gastric ulcers distorting the restoration of mucosal architecture and (2) this animal model is extremely useful for the study of the role of H. pylori in the healing of experimental peptic ulcers.

A method for the direct determination of 18-hydroxycorticosterone (18OHB) in human saliva has been developed and validated. Saliva was collected at 30 min and 1 h intervals between 0600 and 2200 h from healthy men and women for the determination of 18OHB (SHB), aldosterone (SA) and glucocorticoids (SGC = cortisol + cortisone). SHB was highly correlated with SA (r = 0.75; P less than 0.001) but even more highly with SGC (r = 0.89; P greater than 0.001). Multiple regression analysis confirmed that SGC was a more important determinant of SHB than was SA. Though the concentrations of 18OHB and aldosterone were highly correlated there was considerable variation in the 18OHB:aldosterone ratio during the period of saliva collection. This ratio tended to be highest in the morning and lowest in the evening and was weakly correlated with SGC level (r = 0.62; P less than 0.01). The 18OHB:aldosterone ratio in saliva approximates to, and is highly correlated with, that in plasma. We suggest that the fluctuations in SHB:SA ratio correspond to the relative rates of secretion of 18OHB and aldosterone and that this ratio is modulated either by ACTH or by cortisol. Whether this indicates that 18OHB is a by-product of glucocorticoid as well as aldosterone metabolism, or whether this implies a separate physiological role for the steroid remains to be clarified.

An efficient ASIC architecture for the sequential stack decoding (SSD) algorithm used for channel coding is presented. It is different from the maximal likelihood (ML) Viterbi decoder (VD), mainly in the search for the correct memory path. Due to the dedicated memory organization, the storage space and required hardware can be reduced while the decoding efficiency remains almost the same. The proposed architecture results from step by step design of the I/O interface, high-level memory management, dedicated data paths, and controller. The ordering of these steps is important in optimizing the final solution. In addition, the construction of this hardware organization can be made by using the available hardware building blocks. >

Grey markets have troubled international businesses for many years. The main suppliers of grey-market goods are diverters, who obtain brand-owner's authorisation at one country and sells branded goods to a grey marketer at another country in which they are not authorised. This paper proposes a duopoly model that takes the diverter's point of view to answer the unsolved questions in grey marketing. The equilibrium solution is obtained by Cournot assumption, which assumes that each firm acts independently and attempts to maximise its profits by choosing its output. The extension and implications of this model are also discussed.

Various animal models have often been utilized as the basis of studies of the pathophysiology of peptic ulcer disease, however the ultrastructural changes in the evolution of duodenal ulcers produced in experimental animals have not been well elucidated. Utilizing a surgical method developed for the study of gastric ulcers we have established an experimental duodenal ulcer production technique in the rat which is highly reproducible and readily standardized. In the following time sequence study of experimental duodenal ulcers we present the ultrastructural features of ulcer induction and evolution.Duodenal ulcers were produced in 150-200 gram male Sprague Dawley rats by application of 50% acetic acid for 30 seconds through a 3 mm polyethylene tube to the serosa 1.0-1.5 cm distal to the pyloric sphincter. Routine transmission and scanning electron microscopy were performed on duodenal specimens at specific time points subsequent to surgical ulcer generation. Thin sections were stained with uranyl acetate and lead citrate and examined with a Phillip's EM 300 transmission electron microscope. For SEM, specimens were post-fixed in 2% osmium for two days, coated with gold/palladium and examined with JEOL JSM-6100 scanning electron microscope (JEOL, Inc., Peabody, MA).

Effects on transmembrane potentials of cardiotoxin isolated from Formosan cobra venom were studied on rabbit atrial cells by means of electrophysiological techniques. It was found that cardiotoxin at a concentration of 10 −5 g per ml caused a progressive and irreversible decrease of the resting potential in myocardial cells starting 5 min after addition of the toxin. The decrease in maximum diastolic repolarization of the pacemaker type cells occurred much later and to a much less extent. Associated with the decrease of resting potential, the magnitude and rate of rise of the action potential, the overshoot, the time to 80% repolarization and the spike ionic conductance were also decreased. The effect of the toxin on the membrane potential was not altered by either tetrodotoxin or sodium removal but was inhibited by high calcium. It is suggested that disintegration of the membrane structure is responsible for the membrane depolarization.

An electromyographic (EMG) study was made to investigate the actions of the intrinsic laryngeal muscles in the production of Korean stops. The results indicated that coordinated action of the intrinsic laryngeal muscles characterized the different types of Korean stops. Type III (aspirated) stop appeared to be characterized by marked suppression of all the adductor muscles immediately before the articulatory release. In type I (forced) stop, thyroarytenoid (VOC) showed a sharp increase in activity before the stop release, which presumably resulted in an increase in inner tension of the vocal folds as well as in constriction of the glottis during or immediately after the articulatory closure. In type II (lax) stop, the suppression of adductors was less predominant and there was no transient increase in VOC activity before release. It seems reasonable to consider, at least for Korean stops, that the laryngeal articulatory adjustment is not limited in a simple dimension of adduction-abduction of the vocal folds, but another dimension, represented by VOC activity for example, also must be taken into consideration.

By means of Sephadex G-75 column chromatography, Vipera russelli venom was separated into five fractions. The phospholipase A2 (PLA2) activity was concentrated in Frs. II and III. These two PLA2 fractions were rechromatographed on CM-Sephadex C-50. Several subfractions of Fr. II and Fr. III contained PLA2 activities. Frs. III-3, III-6 and III-10 showed single bands in SDS-polyacrylamide gel electrophoresis with molecular weights estimated to be 15,054, 15,167 and 15,029, and isoelectric points of 4.15, 8.80 and greater than 10, respectively. Fr. III-3 had the most potent neuromuscular blocking action on the chick biventer cervicis nerve-muscle preparation, causing a complete neuromuscular blockade at 3 micrograms/ml. The response of the muscle to ACh, tested after complete blockade, was not altered. Most PLA2 subfractions had hypotensive actions in rats at 0.1 mg/kg. In the guinea-pig lung, Frs. II-5, II-7, III-3, III-6 and III-10 increased the perfusion pressure, which may account for part of their hypotensive actions.

Bacterial lipopolysaccharide (LPS) induces the release of tumour necrosis factor (TNF) into serum of mice previously infected with Listeria monocytogenes or immunized with formalin-killed Corynebacterium parvum. This release is greatly reduced by neutralisation of lipid A of LPS with the antibiotic polymyxin B sulfate. The effect is dose-dependent. Base-hydrolysed LPS, which is devoid of lipid A, cannot induce TNF release. Crude lipid A still retains its ability to induce TNF release but is significantly less effective than native LPS molecules. LPS neutralised by polymyxin B also loses its ability to cause high mortality in C. parvum primed mice. These results suggest that lipid A of LPS molecule is important in causing lethality and TNF release in vivo while the polysaccharide portion may be involved in delivering the lipid A moiety to TNF-producing cells.