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Autonomous travel of agricultural machines/robots is achieved by movement along a straight line based on a map with the global positioning system (GPS). However, when farm produce such as lettuce is not grown in a straight line, the robots equipped with GPS might damage the lettuce intended for harvesting. With regard to this problem, autonomous travel using local information can improve harvesting accuracy. In this paper, we propose an autonomous travel method for a lettuce harvester with on-off actuators based on the relative positions of the lettuce and the harvest machine obtained via a camera. This study adopts model predictive control (MPC) to ensure that the vehicle follows the positions of some lettuce located ahead in the same line if the vehicle includes the restriction of turning radius. To facilitate the application of an optimal method for determining an optimal input sequence in MPC, we transform a kinematics model of the vehicle into the time-state control form. The effectiveness of the proposed method is shown through numerical examples.

Among the recently discovered iron-based superconductors, ultrathin films of FeSe grown on SrTiO3substrates have uniquely evolved into a high-transition-temperature (Tc) superconducting material. The mechanisms for the high-Tcsuperconductivity are under debate, with the superconducting gap mainly characterized with in situ analysis for FeSe films grown by molecular beam epitaxy. Here, we investigate the high-Tcsuperconductivity in ultrathin FeSe using an alternative top-down electrochemical etching technique in a three-terminal transistor configuration. In addition to the high-temperature superconductivity in FeSe on SrTiO3, the electrochemically etched ultrathin FeSe transistor on MgO also exhibits superconductivity around 40 K, implying that the application of an electric field effectively contributes to the high-Tcsuperconductivity in ultrathin FeSe regardless of substrate material. Moreover, the observable critical thickness for the high-Tcsuperconductivity is expanded up to 10 unit cells under an applied electric field and the insulator–superconductor transition is electrostatically controlled. The present demonstration implies that the modification of charge imbalance of holes and electrons by the electric-field effect plays a crucial role in inducing high-Tcsuperconductivity in FeSe-based electric double-layer transistors.

Diffuse pulmonary arteriovenous malformations (AVMs) are associated with a poor prognosis and the therapeutic strategy remains controversial. We describe a pediatric patient with diffuse pulmonary AVMs associated with hereditary hemorrhagic telangiectasia (HHT), who presented with two cerebral AVMs in the parietal and occipital lobes as well. Of note, successful bilateral lung transplantation not only improved the hypoxemia but also resulted in size reduction of the cerebral AVMs. Although it is essential to consider involvements other than pulmonary AVMs, especially brain AVMs, to decide the indication, lung transplantation can be a viable therapeutic option for patients with diffuse pulmonary AVMs and HHT.

The authors describe a successful lung transplant in a patient with diffuse pulmonary arteriovenous malformations and hereditary hemorrhagic telangiectasia, focusing on its potential to improve cerebral arteriovenous malformations.

Understanding of the genetic control of female reproductive performance in pigs would offer the opportunity to utilize natural variation and improve selective breeding programs through marker-assisted selection. The Chinese Meishan is one of the most prolific pig breeds known, farrowing 3 to 5 more viable piglets per litter than Western breeds. This difference in prolificacy is attributed to the Meishan's superior prenatal survival. Our study utilized a 3-generation resource population, in which the founder grandparental animals were purebred Meishan and Duroc pigs, in a genome scan for QTL. Grandparent, F1, and F2animals were genotyped for 180 microsatellite markers. Reproductive traits, including number of corpora lutea (number of animals = 234), number of fetuses per animal (n = 226), number of teats (n = 801), and total number born (n = 288), were recorded for F2females. Genome-wide significance level thresholds of 1, 5, and 10% were calculated using a permutation approach. We identified 9 QTL for 3 traits at a 10% genome-wise significance level. Parametric interval mapping analysis indicated evidence of a 1% genome-wise significant QTL for corpora lutea on SSC 3. Nonparametric interval mapping for number of teats found 4 significant QTL on chromosomes SSC3 (P< 0.01), SSC7 (P< 0.01), SSC8 (P< 0.01), and SSC12 (P< 0.05). Partial imprinting of a QTL affecting teat number (P< 0.10) was detected on SSC8. Using the likelihood-ratio test for a categorical trait, 2 QTL for pin nipples were detected on SSC2 and SSC16 (P< 0.01). Fine mapping of the QTL regions will be required for their application to introgression programs and gene cloning.

AbstractThe number and distribution of neurons in the murine neocortex are altered by loss of function of p27Kip1, a cyclin-dependent kinase inhibitor that regulates cell cycle progression at the G1 phase. We show that a temporary decline in the production of non-GABAergic projection neurons occurs in the dorsomedial neopallium of the p27Kip1 knockout mouse during the mid-term of neuronogenesis. It is followed by an augmentation of neuron production later in neuronogenesis leading to an increased production of projection neurons for the upper layers of the neocortex (layers II–IV). p27Kip1 is likely to play a critical role in cell internal regulatory mechanisms of proliferation/differentiation behavior of neural progenitor cells and may be directly involved in the control of neuron number during the period when non-GABAergic projection neurons for layers II–IV are being produced.Copyright © 2004 S. Karger AG, Basel

The diffusion structural analysis (DSA) was used to characterize microstructure changes of hydrous titania gel films under in situ conditions of heating. TG and DTA were used in order to elucidate the processes controlling the formation of anatase film during heating of hydrous titania gel film. The annealing of porosity and near surface structure defects of the dehydrated titania films was indicated by DSA in the temperature range 255–700°C as the decrease of radon release rate. It was demonstrated that the annealing was enhanced on heating in oxygen in comparison with heating in argon. The DSA experimental results were compared with model curves describing the radon diffusion mobility and the annealing of radon diffusion paths.

Emanation thermal analysis (ETA), based on the measurement of the release of radon previously incorporated into the sample, was used to characterize the differences in the thermal behavior porous titania film (thickness 200 nm),when heated in argon and in oxygen, respectively, in the range from 20 to 800°C. It was observed that the annealing of porosity and structure defects in the near surface layers of the porous titania film (anatase) was enhanced on heating in oxygen in comparison to the heating in argon. ETA results were compared with SEM micrographs and XRD patterns of the titania film samples heated to 500 and 800°C, respectively. A mathematical model was used for the evaluation of the temperature dependence of the titania films microstructure development.

The paper reviews the actual state of the development and use of emanation thermal analysis (ETA). Examples of its recent applications are presented. The advantages of ETA in the microstructure characterization of materials under in situ conditions of their heat treatment are outlined.

Emanation thermal analysis (ETA) was used in the characterization of microstructure changes during heating ofprecursors for the titania based materials: hydrous titania, TiO2⋅nH2O (n=0.58) and hydrous titania containing 10% ruthenia,(TiO2)0.9(RuO2)0.1⋅nH2O (n=1.5). The precursors were heated at the constant rate 6 K min−1 in argon flow in the range 20–1000°C. ETA results were compared with the theoretical curves simulating the temperature dependences of radon release rate, E(T). Two mathematical models were used in the simulation. The models considered either subsequent or simultaneous solid state processes (i.e. dehydration, crystallization orphase transition, resp.) during thermal treatment of titania based materials. A good agreement was found between experimental and the simulated ETA curves. The results of ETA were confirmed by XRD patterns of intermediate products of thermal treatment of the precursors.

Results of emanation thermal analysis (ETA) characterizing microstructure changes of SiC based materials during heat treatment in argon are demonstrated. This method made it possible to reveal fine changes of the texture of SiC nano-sized powders, SiC micro-sized powders and SiC whiskers under in situconditions of the heating. ETA curves can serve as ‘fingerprints’ of the respective samples.

Carcasses from Japanese Black steers were used to obtain prediction equations for carcass composition from information derived by computer image analysis of carcass cross-section images. The total weights of lean, fat, and bone were obtained from the left sides of 55 carcasses (Data Set I) and 18 carcasses (Data Set II) by physical dissection. The information such as total lean, fat, and bone areas in the cross-sections; muscle area, muscle circumference, short and long radius axis lengths, and direction of long radius axis; and geometric distance between any two muscle centers of gravity was obtained by scanning and image analysis of pictures of the cross-sections of the beef side at the 6th/7th rib interface. The coefficients of determination of the multiple regression equations estimated from Data Set I for kilograms of lean, fat, and bone were 0.76, 0.82, and 0.69, respectively, whereas for the percentages of lean, fat, and bone they were 0.57, 0.66, and 0.42, respectively. The multiple regression equations from Data Set I was applied to Data Set II in order to test the applicability of the prediction equations obtained. The correlation coefficients between the value predicted by the multiple regression equation and the measurement obtained by physical dissection for kilograms of lean, fat, and bone were 0.71, 0.72, and 0.70, respectively, whereas those for the percentages of lean, fat, and bone were 0.63, 0.44, and 0.29, respectively. The results indicate that the information obtained from the carcass cross-sections by the computer image analysis method can be used to predict carcass composition in Japanese Black steers.

Processes taking place during formation of B-C-N ceramics by thermal treatment of organic precursors were investigated using emanation thermal analysis (ETA), differential thermal analysis (DTA) and thermogravimetry (TG). An additional information about thermal behavior of precursors used for preparation of BC4N, BN and CNx ceramic systems by heating in argon up to 1100°C was obtained. The ETA enabled us to characterize microstructure changes in the samples at in situ conditions of thermal treatment. A good agreement of ETA, TG and DTA results was found.

DSC was used for heat capacity measurements of pure RuO2in the temperature range from 300 to 1170 K of solid solutions corresponding to the compositions of (Ti1−xRux)O2(x≤0.15 and x≥0.85) and in the temperature range from 300 to 1550 K of pure TiO2. The analysis of experimental data obtained within ±2% of accuracy has shown that the characteristic temperatures representing the harmonic lattice vibrations do not strongly depend on the chemical composition x. It was demonstrated that non-harmonic heat capacity is strongly correlated to x. The existence of additional excess heat capacity was observed with the mixed oxide solid solution samples of low Ru content and explained by the defect formation model.

The preparation of rutile type solid solutions in (TiO2)x-(RuO2)1−xsystem in the 0≤x≤0.7 concentration range is described. The single phase solid solutions are formed by controlled nanocrystallization of amorphous gels prepared by the sol-gel method. The kinetics of this crystallization process has been analyzed. It was found that the crystallization does not correspond to the Johnson-Mehl-Avrami model and it can be described by the two-parameter Šesták-Berggren kinetic model.

Metastable defects of oxygen in calcium titanate thin films with perovskite structure were studied. Thin films of calcium titanate were deposited by a magnetron sputtering method. The oxygen defects were evaluated, using the results of oxygen diffusion experiments. The thin film process had tendencies of creation of a large amount of oxygen point defects and the wide range of non equilibrium solid solution at room temperature. Thecrystal distortion was increasing with deviation from the stoichiometric composition. Although the metastable defects were decreasing due to the annealing, annealed samples had more oxygen defects in a few magnitude orders than single crystals.

Emanation Thermal Analysis (ETA) was used to characterize microstructure changes of hydrous ruthenia and hydrous ruthenia-titania as precursors for preparation of RuO2and (RuO2)0.9-(TiO2)0.lby heating in the temperature range of 20–600°C in argon. A good agreement was found between ETA, TG and DTA results, X-ray diffraction patterns and surface area measurements of intermediate products of the thermal treatment.

The volume and enthalpy relaxation rate of inorganic glasses and organic polymeric materials subjected to temperature jump ΔT has been analyzed. It is shown that the relaxation behavior in isothermal conditions can be compared on the basis of the fictive relaxation rate defined as Rf=(dTf/dlogt)i. No significant difference between volume and enthalpy relaxation rate has been found for all materials examined. A simple equation relating the Rf and parameters of Tool-Naraynaswamy-Moynihan (TNM) phenomenological model has been derived. This equation predicts increasing Rf with the magnitude of temperature jump. It seems that correct determination of TNM parameters might be problematic for slowly relaxing polymers as the effect of these parameters becomes comparable with experimental uncertainty.

The role for intracellular Ca2+ in modulating activity of the Na+/H+ exchanger was studied in cultured vascular smooth muscle cells. Na+/H+ exchange was activated by four distinct stimuli: 1) phorbol 12-myristate 13-acetate, 2) thrombin, 3) cell shrinkage, and 4) intracellular acid loading. [Ca2+]i was independently varied between 40 and 200 nM by varying the bathing Ca2+ from 10 nM to 5.0 mM. Thrombin-induced intracellular Ca2+ transients were blocked with bis(2-amino-5-methylphenoxy)ethane-N,N,N′,N′-tetraacetic acid tetraacetoxymethyl ester (MAPTAM). In the absence of stimulators of Na+/H+ exchange, varying [Ca2+]i above or below the basal level of 140 nM did not activate Na+/H+ exchange spontaneously. However, varying [Ca2+]i did affect stimulus-induced activation of Na+/H+ exchange. Activation of the exchanger by phorbol 12-myristate 13-acetate was blunted by reduced intracellular Ca2+ (half-maximal activity at 50-90 nM [Ca2+]i), consistent with a Ca2+ requirement for protein kinase C (Ca2+/phospholipid-dependent enzyme). Activation of the exchanger by thrombin in protein kinase C-depleted cells was also sensitive to reduced intracellular Ca2+ (half-maximal activity at 90-140 nM [Ca2+]i) and was increased 40% by raising [Ca2+]i to 200 nM. Activation of the exchanger by cell shrinkage or intracellular acid loads was not significantly affected over the range of [Ca2+]i tested. Thus, altered [Ca2+]i does not itself affect Na+/H+ exchange activity in vascular smooth muscle but instead modulates activation of the transporter by particular stimuli.

Arachidonate metabolites have many kinds of bioactivities. Thromboxane A2(TXA2) stimulates platelet aggregation and vasoconstriction, whereas prostaglandin I2(PGI2) antagonises its activities. Thromboxane B2(TXB2) and 6-keto-prostaglandin F1α(6-keto-PGF1α) are determined in biological materials. Production of TXB2, 6-keto-PGF1αand leukotriene C4(LTC4), which have potent vascular permeability, was measured by radioimmunoassay in experimental spinal cord injured animals. TXB2level in the rat spinal cord reached a peak concentration of 133.6 ± 3.8 pmol/g cord, and 6-keto-PGFlfVincreased to 26.2 ± 11.7 pmol/g cord 5 minutes after the injury. There was good correlation between TXB2production and vascular damage as monitored by fluorescein uptake. When OKY-046 ((E)-3-[4-(1-imidazolylmetyl) phenyl]-2-propenoic acid), which selectively inhibits TXA2synthetase activity, was administered 10 minutes before injury, the increase in TXB2production was inhibited by more than 80%, but the degree of vascular damage was reduced by only 40%. In the guinea pig spinal cord, LTC4levels reached a peak concentration of 2.2 ± 0.4 pmol/g cord 10 minutes after compression, while that of TXB2reached 146.8 ± 6.2 pmol/g cord. The increased production of TXB2was correlated with the degree of compression injury while that of LTC4production did not. These findings suggest that vasoactive eicosanoids, TXA2, PGI2and LTC4, play important roles in secondary damage following spinal cord injury, although their roles may be different among species of animals.

We have identified and characterized lambda bacteriophage clones containing genomic DNA encoding rat malic enzyme [(S)-malate:NADP+ oxidoreductase (oxaloacetate-decarboxylating); EC 1.1.1.40]. The malic enzyme gene is unexpectedly large, spanning at least 95 kilobases. It is divided into 14 exons that range in size from 76 to 1513 base pairs. The sizes and boundaries of the exons were determined by Southern blotting and DNA sequencing. The sequences at the 5' and 3' ends of each intron conformed to the consensus sequence for mammalian introns. S1 nuclease and primer-extension assays showed that transcription of the malic enzyme gene initiates at multiple sites, the strongest one at position -31 relative to the ATG. "TATA and CCAAT box" homologies are not present in the proximal promoter region. Analysis of the 3' end of the gene showed that the utilization of alternate polyadenylylation signals in exon 14 results in two mRNAs with 3' untranslated regions of 345 and 1345 nucleotides, respectively.

The nucleotide and predicted amino acid sequences of two variant cDNAs [rat brain thyroid hormone receptor (rTR alpha) vI and vII], isolated from a rat brain cDNA library by using the Pst I fragment of v-erbA, showed virtual identity with the rat brain thyroid hormone receptor (rTR alpha) [Thompson, C. C., Weinberger, C., Lebo, R. & Evans, R. M. (1987) Science 237, 1610-1614] in the putative DNA binding domain and in the first 180 amino acids of the hormone binding domain but no similarity except for 5 amino acids at the extreme 3' end. Isolation and sequencing of the 3' end of the gene coding for rTR alpha, vI and vII mRNAs revealed that the 3' heterogeneity is due to alternative splicing of the primary transcripts of the same gene. RNA transfer blot analyses with probes unique to rTR alpha, rTR alpha vI, and rTR alpha vII showed that only the variant mRNAs are abundantly expressed in rat brain, contrary to the previously reported high-level expression of rTR alpha. Since in vitro translation products of rTR alpha vI and rTR alpha vII did not bind thyroid hormones specifically, our findings explain the discrepancy between the reported abundance of the receptor mRNA and the low receptor levels determined by ligand binding studies in rat brain. These variant mRNAs are also expressed in kidney, heart, spleen, and liver, albeit at lower levels. The presence of an intact DNA binding domain in rTR alpha vI and rTR alpha vII suggests that the variants might have modulating functions in thyroid hormone action.

We estimated the severity of coronary artery disease by the continuous-recording method of exercise two-dimensional echocardiography (Ex.2DE) in 56 patients with angiographically significant coronary artery stenosis (>50% diameter narrowing) who had undergone both Ex.2DE and coronary angiography. Patients were divided into two groups on the basis of findings of coronary angiography: group 1 had 50% to 89% stenosis (n=24) and group 2 had 90% or greater stenosis (n=32). The sensitivity and specificity of Ex.2DE for the detection of ischemic segments were 82% and 88%, respectively, in the overall patient population. The sensitivity was 67% in group 1 and 94% in group 2. Hyperkinesis occurred at the beginning of exercise in 21 (88%) of 24 patients in group 1 and in 15 (47%) of 32 patients in group 2 (p<0.05). Our findings demonstrated that patients who did not show hyperkinesis at the beginning of exercise had more severe coronary artery disease. Careful observation of serial wall motion during exercise by the continuous-recording method may provide important information about myocardial ischemia.

Thyrotropin Binding Inhibiting Immunoglobulins (TBII) were measured in sera of 240 patients with Graves’ disease who were followed 0–25 yr as a cross-sectioned study (21 untreated, 189 under therapy and 30 T3-suppressible and drug-discontinued patients) by using solubilized porcine thyroid TSH receptor. Assays were performed by using 50 μl of serum. All untreated 21 patients showed positive TBII. Frequency of positive patients decreased yearly with treatment although 36% of patients remained positive after 6 yr of therapy. After that time TBII were positive in 61 % of follow-up patients and in 16 positive patients who have been treated for more than 10 yr, drug therapy could not be stopped because of recurrence. TBII were positive in 6 of 30 T3-suppressible patients. As a longitudinal study changes in TBII were studied in 10 patients at the time of relapse or exacerbation. TBII increased in parallel with increases in thyroid hormone concentrations in 3 of 10 patients. Six of the others showed earlier or later TBII increases than those in thyroid hormones. One patient did not show any change in TBII, albeit thyroid hormone concentrations were found to be increased. Our observations suggest that abnormal IgGs detected as TBII in sera of patients with Graves’ disease by the present method do not explain the occurrence of hyperthyroidism.

The mechanisms by which triiodothyronine (T3) regulates gene transcription are inadequately understood. In order to examine the effect of T3on transcriptional mechanisms, we utilized several techniques to characterize trans-acting factors which interact with cis-regulatory elements of the promoter for the T3-responsive rat malic enzyme gene. Transcription of deletion mutants of the promoter by HeLa extracts revealed the existence of three cis-regulatory elements at −144 to −123, −70 to −50, and −30 to +5 (relative to the cap site at +1). DNase I footprinting disclosed the presence of proteins which bound to each of these regions. Gel mobility shift assays showed that specific binding of liver nuclear proteins to two of these regions (−144/−114 and −76/−47) was diminished in hypothyroid and elevated in hyperthyroid rats. Similar but less marked effects of T3on the binding of kidney (a T3-responsive tissue) nuclear proteins to the −76/−47 and cap site regions were observed while binding of testis (a T3-nonresponsive tissue) nuclear proteins was unaffected by T3treatment. Changes in the magnitude and time course of binding of liver proteins to this promoter correlated closely with previously documented T3-induced increases in the hepatic malic enzyme gene transcription rate. These results are consistent with a model in which the regulation of malic enzyme gene transcription by T3in responsive tissues is mediated in part by hormone-induced increases in the binding of trans-acting factors to cis-regulatory elements.

The thyroid hormone nuclear receptor is a chromatin-associated protein regulating expression of specific genes. Acetylation of nucleosomal core histones is thought to be one of the factors regulating transcriptional activity of chromatin, and it is suggested that this reaction negatively regulates thyroid hormone receptor levels in GH1 cells (Samuels, H.H., Stanley, F., Casanova, J., and Shao, T. C. J. Biol. Chem. 255, 2499-2508). In the present study, we found that n-butyrate, a potent inhibitor of histone deacetylase, increases thyroid hormone receptor levels in three distinct non-pituitary cells without changing binding affinity. This effect appeared within 30 min and reached a plateau (240% of control) after a 6-h treatment, before important cellular functions were affected. This effect was time-dependent, dose-dependent, reversible, and paralleled the changes in the electrophoretic mobilities of histones H3 and H4. n-Butyrate prolonged the receptor half-life, and this prolongation corresponded to the increase of receptor levels. Thyroid hormone did not reduce its own receptor levels or influence the effect of n-butyrate. Considering the difference between GH1 cells and non-pituitary cells in the regulation of thyroid hormone receptor levels, our observations, together with those of Samuels et al., suggest the possibility that the acetylation of chromatin-associated proteins has a physiological significance in the regulation of thyroid hormone nuclear receptor levels.

We previously identified functional histamine H2 receptors on human HL-60 promyelocytic leukemia cells [J. Biol. Chem. 264: 18356-18362 (1989)]. In the present study, we have compared the action of histamine-albumin conjugates on H2 receptor activation with that of histamine alone. Both histamine and conjugates increased intracellular levels of Ca2+ in an H2 receptor-specific manner. However, binding of fluoresceinated histamine-albumin conjugates to HL-60 cells was not dissociated by 10(-4) M unlabeled histamine, although this concentration of histamine significantly desensitized conjugate responses. These data suggest that histamine-albumin conjugates not only activate H2 receptors but also bind to HL-60 cells nonspecifically or in an H2 receptor-unrelated manner. Moreover, histamine-induced Ca2+ mobilization was transient, whereas conjugate-induced Ca2+ mobilization was sustained for more than 10 min, as a result of the influx of extracellular Ca2+. Therefore, the functional difference between histamine and conjugates may provide a good model for the further understanding of the activation mechanisms of receptor-operated Ca2+ influx.

Abstract: The mixed-valence state of Prussian blue and its thermal decomposition products has been studied by Mssbauer and infrared spectra, and X-ray powder diffraction and conductivity measurements. The57Fe Mssbauer spectra have revealed that the coordination environment of Prussian blue is not changed by the heat-treatment at lower than 200C while the flipping of the cyano ligands takes place when the heat-treatment temperature exceeds 250C. The electrical conductivity of the Prussian blue samples heat-treated in vacuo at 300 and 350C is higher than that of the samples heat-treated at lower temperatures. All the spectral measurements have demonstrated that a new mixed-valence state is produced in Prussian blue by thermally flipping the cyano ligand and quenching the flipped cyano ligand to liquid nitrogen temperature.