An iterative learning strategy for the auto-tuning of the feedforward and feedback controller in type-1 diabetes

This paper proposes a scheme for the control of the blood glucose in subjects with type-1 diabetes mellitus based on the subcutaneous (s.c.) glucose measurement and s.c. insulin administration. The tuning of the controller is based on an iterative learning strategy that exploits the repetitiveness of the daily feeding habit of a patient. The control consists of a mixed feedback and feedforward contribution whose parameters are tuned through an iterative learning process that is based on the day-by-day automated analysis of the glucose response to the infusion of exogenous insulin. The scheme does not require any a priori information on the patient insulin/glucose response, on the meal times and on the amount of ingested carbohydrates (CHOs). Thanks to the learning mechanism the scheme is able to improve its performance over time. A specific logic is also introduced for the detection and prevention of possible hypoglycaemia events. The effectiveness of the methodology has been validated using long-term simulation studies applied to a set of nine in silico patients considering realistic uncertainties on the meal times and on the quantities of ingested CHOs.     

The power of allele frequency comparisons to detect the footprint of selection in natural and experimental situations

Recently, inter-population comparisons of allele frequencies to detect past selection haven gained popularity. Data from genome-wide scans are used to detect the number and position of genes that have responded to unknown selection pressures in natural populations, or known selection pressures in experimental lines. Yet, the limitations and possibilities of these methods have not been well studied. In this paper, the objectives were (1) to investigate the distance over which a signal of directional selection is detectable under various scenarios, and (2) to study the power of the method depending on the properties of the used markers, for both natural populations and experimental set-ups. A combination of recurrence equations and simulations was used. The results show that intermediate strength selection on new mutations can be detected with a marker spacing of about 0.5 cM in large natural populations, 200 to 400 generations after the divergence of subpopulations. In experimental situations, only strong selection will be detectable, while markers can be spaced a few cM apart. Adaptation from standing variation in the base population will be hard to detect, though some solutions are presented for experimental designs.     

Yield stability of determinate and indeterminate dry bean cultivars

Summary Yield stability of determinate and indeterminate dry bean (Phaseolus vulgaris L.) cultivars was compared using regression of genotypic performance on environmental means. Yields of 28 dry bean cultivars differing in plant growth habit and commercial class designation were obtained from 42 Michigan performance nurseries over the 6 year period 1980 to 1985. The determinate type I large-seeded kidney and cranberry bean cultivars had below-average seed yield and large mean square deviations from regression. Lower yielding determinate small-seeded navy cultivars had low deviation mean square values, while higher yielding determinate navy cultivars had correspondingly higher mean square deviations from regression. Although seed yield of cultivars with an indeterminate growth habit was greater than determinate cultivars, prostrate type III indeterminate cultivars had deviation mean square values equivalent to those of large-seeded determinate cultivars. The erect, short vine type II indeterminate cultivars (architypes) had greater than average seed yields and minimum deviations from regression. Compared with other plant types, the architype group showed a greater yield response to more productive environments, with regression coefficient values significantly greater than unity. These results indicate that the type II growth habit offers the breeder the best opportunity of obtaining greater seed yield without incurring loss of yield stability as occurs with the type I and type III growth habits. Since the dry bean cultivars utilized in this study represent two distinct centers of domestication, the regression analysis suggests that cultivars from the predominant genetic center demonstrate more yield stability. A non-significant rank correlation coefficient between the combined and separate analyses for deviation mean square values of large-seeded cultivars implies that commercial dry bean classes should be compared separately based on center of domestication.Contributions from Michigan Bean Commission, Michigan Bean Shippers Assoc. and Michigan Agric. Exp. Sta., Michigan Agric. Exp. Sta. Journal Article No. 11986     

Eigenschaften des Elektronentransportsystem von Mitochondrien des Protisten Acanthamoeba castellanii Neff. I. Zum Einfluß von Hemmstoffen auf verschiedene Akzeptorsysteme, getested mit einer modifizierten Thunbergtechnik

ZUSAMMENFASSUNG. Die Reduktionsgeschwindigkeit künstlicher Elektronenakzeptoren wurde mittels einer modifizierten Thunbergtechnik in Gegenwart isolierter Mitochondrien des Protisten Acanthamoeba castellanii Neff photometrisch gemessen. Die mit verschiedenen Elektronenakzeptoren und Atmungsketteninhibitoren gewonnenen Meßergebnisse erlauben uns folgendes Bild von der Konstitution der Atmungskette zu entwerfen: a) Der Elektronentransport läuft mindestens bis zum Cytochrom b /Coenzym Q-Komplex auf zwei verschiedenen Wegen ab. b) Eine Stimulierung sowohl des Succinat-Jodnitrotetrazolium-chlorid als auch des NADH-Ferricyanid Reduktasekomplexes unter dem Einfluß von Antimycin A läßt vermuten, daß in der Atmungskette dieses Protisten gewisse Nebengleise des Elektronentransports besonders gangbar sind.
SYNOPSIS. The reduction of artificial electron acceptors by isolated mitochondria of Acanthamoeba castellanii was measured by a modified Thunberg technic. The results with different electron acceptors and respiratory chain inhibitors suggest the following scheme for the constitution of the respiratory chain: a) the chain is divided into 2 different sequences, at least up to the cytochrome b /coenzyme Q complex. b) As seen from the stimulation of the succinate-iodonitrotetrazolium chloride and NADH-ferricyanide reductase complexes by antimycin A, certain alternate pathways of electron transport become more important than the normal one.     

Using Echo Ultrasound from Schooling Fish to Detect and Classify Fish Types

Fish finders have already been widely available in the fishing market for a number of years.However,the sizes of these fishfinders are too big and their prices are expensive to suit for the research of robotic fish or mini-submarine.The goal of thisresearch is to propose a low-cost fish detector and classifier which suits for underwater robot or submarine as a proximity sensor.With some pre-condition in hardware and algorithms,the experimental results show that the proposed design has good per-formance,with a detection rate of 100 % and a classification rate of 94 %.Both the existing type of fish and the group behaviorcan be revealed by statistical interpretations such as hovering passion and sparse swimming mode.     

The effects of different PMSG doses on estrus behavior and pregnancy rate in Angora goats

Artificial insemination protocols depend on efficient behavioral estrus detection and insemination time in Angora goat. Therefore, we aim to determine the accuracy of an estrus scoring system in Angora goats with different PMSG doses during the breeding season. Does (n: 260) were randomly divided into three groups: group-1 (n: 93), group-2 (n: 85) and group-3 (n: 82). All animals received an intravaginal sponge on day 0 for 11 days, and on the day of sponge insertion 150 μg prostaglandin F2Α was administered. Pregnant mare’s serum gonadotropin was injected 300, 400 and 500 IU intramuscularly 24 h before sponge removal to groups 1, 2 and 3, respectively. Estrus signs were detected with a teaser buck, 24 h after sponge removal according to a visual scoring system. Artificial insemination was performed with 0.25 ml fresh diluted semen at 43 to 45 h after sponge removal. Differences were observed within PMSG groups in terms of standing, tail wagging, courtship behavior, vaginal discharge and vaginal hyperemia (P<0.001). Nevertheless, the most accurate indicators of estrus that result in pregnancy were tail wagging and courtship behavior followed by standing estrus (P<0.05). According to the results obtained, 300 IU PMSG dose is sufficient, both to inseminate at a fixed time (43 to 45 h after sponge removal) and to record the estrus behavior by teaser male 24 h after sponge removal. Higher PMSG doses (400 to 500 IU) altered the timing of ovulation; specifically, 500 IU dose shortened the duration of estrus behaviors. In conclusion, even though the different doses of PMSG displayed similar effects on estrus synchronization and pregnancy rates, we concluded that tail wagging, courtship behavior and standing heat are the most reliable estrus signs for artificial insemination in Angora goat.     

Validation of the first step of the heuristic refinement method for the derivation of solution structures of proteins from NMR data

A new method for the analysis of NMR data in terms of the solution structure of proteins has been developed. The method consists of two steps: first a systematic search of the conformational space to define the region allowed by the initial set of experimental constraints, and second, the narrowing of this region by the introduction of additional constraints and optional refinement procedures. The search of the conformational space is guided by heuristics to make it computationally feasible. The method is therefore called the heuristic refinement method and is coded in an expert system called PROTEAN. The paper describes the validation of the first step of the method using an artificial NMR data set generated from the known crystal structure of sperm whale carbon monoxymyoglobin. It is shown that the initial search procedure yields a low-resolution structure of the myoglobin molecule, accurately reproducing its main topological features, and that the precision of the structure depends on the quality of the initial data set.     

Engineering lysine‐rich caleosins as carrier proteins to render biotin as a hapten on artificial oil bodies for antibody production

It has been demonstrated that caleosin alone is sufficient to stabilize artificial oil bodies. A series of recombinant caleosins, mutated with 3, 5, 8, 11, 13, 15, and 17 extra Lys residues and over‐expressed in Escherichia coli, were used as carrier proteins to render biotin as a hapten on the surface of artificial oil bodies for antibody production. Biotinylation levels of the recombinant caleosins were step‐wisely elevated as the number of extra Lys residues increased, and the biotinylated Lys residues were identified by mass spectrometric analysis. Polyclonal antibodies against biotin were successfully generated in rats injected with artificial oil bodies constituted with each of the biotinylated caleosins. Moreover, those generated via the biotinylated caleosins with eight or more extra Lys residues no longer recognized caleosin. It appears that engineered Lys‐rich caleosins are suitable carrier proteins for the production of antibodies against small molecules. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011     

The Genetic Basis of Morphological Diversity in Domesticated Goldfish

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