Exceptional hexose-fermenting ability of the xylitol-producing yeast Candida guilliermondii FTI 20037.

The yeast Candida guilliermondii FTI 20037 is well-known for its ability to produce xylitol from xylose. Recently, this strain was found to produce greater than 5% (w/v) ethanol from glucose. This level of ethanol is typically not exceeded by wild-type strains of other native pentose-fermenting yeasts. This prompted the current study to examine the ability of C. guilliermondii FTI 20037 to utilize and ferment high concentrations of each of the hexoses commonly found in lignocellulosic hydrolysates. In defined media, FTI 20037 fermented 14.4%-25.9% (w/v) of glucose, mannose or galactose individually to ethanol in concentrations ranging from 6% to 9.3% (w/v). Fermentation was completed within 36 h (for glucose) to 100 h (for galactose). In 25.9% (w/v) glucose, FTI 20037 produced 9.3% (w/v) ethanol within 40 h. FTI 20037 produced xylitol exclusively when xylose was given as the sole carbon source. The strain utilized arabinose poorly. Under the same fermentation conditions, an industrial Saccharomyces cerevisiae strain produced slightly higher levels of ethanol [9.9% (w/v)] from 25.0% (w/v) glucose. Another pentose-fermenting yeast Pachysolen tannophilus also fermented high concentrations of glucose and mannose to produce relatively high peak ethanol concentrations; however, this yeast required considerably longer to completely consume these hexoses. The ability of FTI 20037 to produce high level of ethanol rapidly from glucose is remarkable. To our knowledge, this is the first known instance of a non-modified native xylose-fermenting yeast strain able to produce such high levels of ethanol from glucose as rapidly as S. cerevisiae in a defined medium.

[Experimental study on animal with automatic drug injection based on predictive control for vascular interventional therapy].

This paper focuses on the animal experiment of automatic drug delivery based on predictive control for vascular interventional therapy. Improvement of drug delivery system based on predictive control used in simulated experiments was put forward after the presence of time varying parameters and the characteristics of individual differences of animal had been studied. The adaptability of time varying parameters and fault tolerance of the system were also enhanced. Different injection methods were tested on animals. It is proved that higher target blood concentration can be reached while injecting during diastolic than that while injecting during systolic or injecting at a constant speed within the whole cardiac cycle. The results also showed that the improved drug injection system based on predictive control which synchronizes with the cardiac cycle could be applied to clinical trials.

Hemicelluloses prior to aspen chemithermomechanical pulping: pre-extraction, separation, and characterization.

A portion of hemicelluloses and acetic acid can be pre-extracted with dilute sulfuric acid prior to the aspen chemithermomechanical pulp process. The streams collected from the second press-impregnation stage after acid pre-extraction contain a significant amount of acid pre-extracted hemicelluloses. Most of the total sugars obtained from the pressate were xylan, in which xylan was further hydrolyzed to sugar monomers under the acid pre-extraction condition. To fully understand the characteristics of hemicelluloses yielded prior to pulping, the pre-extracted hemicelluloses were separated and characterized by FT-IR, (1)H NMR, and thermogravimetric analysis in this study. Most of the FT-IR bonds from the hemicelluloses agreed well with the other two spectra of birch xylan and CA0050 xylan, except a new absorption at 1734 cm(-1) contributed to acetyl groups. The hemicelluloses obtained from acid pre-extraction began to decompose significantly at about 225 °C, slightly lower in comparison with organosolv and alkaline hemicelluloses reported in the literature.

Extracting hemicelluloses prior to aspen chemi-thermomechanical pulping: Effects of pre-extraction on pulp properties.

Pre-extraction of hemicelluloses prior to pulping and conversion of the extracted hemicelluloses to other by-products will provide additional revenues to traditional pulp and paper industry. The effects of hemicelluloses pre-extraction with sulfuric acid on aspen (Populus tremuloides) chemi-thermomechanical pulp (CTMP) properties were investigated in this study. The sulfuric acid pre-extraction resulted in a release of 11% of hemicelluloses (determined as xylan) and acetic acid, especially at the second press-impregnation stage. Compared with CTMP without acid pre-extraction, the acid pre-extraction significantly reduced refining energy to a given freeness, and the pulps produced from acid pre-extracted chips have lower shives, higher strength properties except zero-span breaking length, lower bulk, but lower brightness at a similar specific refining energy. This study provides useful information for integration of biorefinery in mechanical pulp mills in the future.

[A simulating excorporeal experimental system for automatic drug injection based on predictive control in vascular interventional therapy].

This paper discusses an in vitro simulating experiment for drug injection based on predictive control in vascular interventional therapy. The relationship between the model of drug injection and the pulsatile blood flow was studied. The experimental model for predictive control of drug injection was tested and verified so as to support the future animal experimental modeling with the data acquired from the in vitro simulating experiment.

[The advances of automatic drug infusion].

The development of automatic drug delivery is reviewed in this paper. The control-relevance of models, the relevant algorithm, the system running and the simulation effect are introduced. The value for clinical application of each case is assessed. The new advances and high-lights of researches are discussed.

[Image processing applying in analysis of motion features of cultured cardiac myocyte in rat].

Study of mechanism of medicine actions, by quantitative analysis of cultured cardiac myocyte, is one of the cutting edge researches in myocyte dynamics and molecular biology. The characteristics of cardiac myocyte auto-beating without external stimulation make the research sense. Research of the morphology and cardiac myocyte motion using image analysis can reveal the fundamental mechanism of medical actions, increase the accuracy of medicine filtering, and design the optimal formula of medicine for best medical treatments. A system of hardware and software has been built with complete sets of functions including living cardiac myocyte image acquisition, image processing, motion image analysis, and image recognition. In this paper, theories and approaches are introduced for analysis of living cardiac myocyte motion images and implementing quantitative analysis of cardiac myocyte features. A motion estimation algorithm is used for motion vector detection of particular points and amplitude and frequency detection of a cardiac myocyte. Beatings of cardiac myocytes are sometimes very small. In such case, it is difficult to detect the motion vectors from the particular points in a time sequence of images. For this reason, an image correlation theory is employed to detect the beating frequencies. Active contour algorithm in terms of energy function is proposed to approximate the boundary and detect the changes of edge of myocyte.

[Image processing method based on prime number factor layer].

In sport games, since the human body movement data are mainly drawn from the sports field with the hues or even interruptions of commercial environment, some difficulties must be surmounted in order to analyze the images. It is obviously not enough just to use the method of grey-image treatment. We have applied the characteristics of the prime number function to the human body movement images and thus introduce a new method of image processing in this article. When trying to deal with certain moving images, we can get a better result.

[The numerical simulation of pulsatile flow in a tapered blood vessel].

The tapered blood vessel is associated with the human physiological pulsatile blood flow in this study to address the questions about the developing flow. The geometry model of tapered blood vessel, theoretical models of blood flow, physiological boundary conditions and calculation conditions are proposed. An average blood flow function is established according to the physiological pulsatile flow conditions. The pulsatile flow in a 3-D tapered blood vessel is simulated numerically with the flow function. The distributions of velocity and pressure on different time of the cardiac cycle are obtained. The numerical simulation outcomes are compared with the experimental and analytical results. The characteristics of the pulsatile flow in a tapered blood vessel are discussed in this paper.

[A simulating experimental system for interventional treatment of lung cancer].

In order to go deeply into the researches on the theory of hemodynamics for interventional treatment of lung cancer, we have designed a simulating experimental system. Using the experimental system, we can simulate the operation process and test the effect of drug infusion under a variety of physiological parameters. The parameters that admit of adjustment are: cardiac output, blood pressure of aorta, waveform of pressure, pulse period, blood flow in bronchial artery and different types of catheter, injecting velocity, injecting technique, etc. In addition, the entrance position and blood vessel diameter of small embranchment artery can be changed. In this paper are presented the application of our pH-testing method to natural infusion region and the determined representational shape and size.

[A system for testing alternating frequency properties of body fluid and tissues].

The electric properties of biotic tissues are of importance to our understanding biotic substances even life. But the measurement taken in this aspect is different from the measurement of ordinary materials, we need a special testing instrument for living substances. In order to understand the alternating frequency properties of body fluid and tissues in detail, we have developed an electricity characteristic testing system, which is more proper for testing living substances. This system adopts advanced measuring method and expert circuit. As the measure and the control core, the single chip processor is used. This system has wide frequency range and wide impedance testing range, much more adapted objects, and it is dependable, more precise and intelligent. The application of this system in practical testing has obtained optimal results.