油藏管理技术展望

油藏开采期限是旨从勘探发现油田开妈，继之以油藏定边、油田开发、以及进行一次，二次及三次采油直到最后废弃为止的整个过程。在油藏开发的全过程中，使油藏开采作业产生最大的经济效益是油藏管理的关系。     

Automated zebrafish chorion removal and single embryo placement: optimizing throughput of zebrafish developmental toxicity screens

The potential of the developing zebrafish model for toxicology and drug discovery is limited by inefficient approaches to manipulating and chemically exposing zebrafish embryos-namely, manual placement of embryos into 96- or 384-well plates and exposure of embryos while still in the chorion, a barrier of poorly characterized permeability enclosing the developing embryo. We report the automated dechorionation of 1600 embryos at once at 4 h postfertilization (hpf) and placement of the dechorionated embryos into 96-well plates for exposure by 6 hpf. The process removed ≥95% of the embryos from their chorions with 2% embryo mortality by 24 hpf, and 2% of the embryos malformed at 120 hpf. The robotic embryo placement allocated 6-hpf embryos to 94.7% ± 4.2% of the wells in multiple 96-well trials. The rate of embryo mortality was 2.8% (43 of 1536) from robotic handling, the rate of missed wells was 1.2% (18 of 1536), and the frequency of multipicks was <0.1%. Embryo malformations observed at 24 hpf occurred nearly twice as frequently from robotic handling (16 of 864; 1.9%) as from manual pipetting (9 of 864; 1%). There was no statistical difference between the success of performing the embryo placement robotically or manually.     

Consensus design of repeat proteins

Consensus design is a valuable protein-engineering method that is based on statistical information derived from sequence alignments of homologous proteins. Recently, consensus design was adapted to repeat proteins. We discuss the potential of this novel repeat-based approach for the design of consensus repeat proteins and repeat protein libraries and summarize recent results from such experiments.     

Textile effluent treatment in a UASB reactor followed by submerged aerated biofiltration

An upflow anaerobic sludge bed (UASB)-submerged aerated biofilter (SAB) system that treats effluents from a jeans factory was evaluated. The 210-day operational period was divided into three phases (PI, PII and PIII), each with a different hydraulic retention time (HRT in h) and organic loading rate (OLR in kg COD/m3.d). In PI, the best performance was achieved using the UASB (HRT 24, OLR 1.3) with COD and color removal efficiencies of 59 and 64%, respectively; the corresponding values were 77 and 86% for the final effluent. In PII, the efficiencies were 50 and 55% using the UASB (HRT 16, OLR 1.2), respectively, and 69 and 81% for the final system effluent, respectively. In PIII, the UASB (HRT 12 and ORL 3.2) showed the poorest performance; the efficiencies decreased to 48 and 50%, respectively. The same phenomenon occurred in the system with corresponding efficiencies decreasing to 69 and 61%. Throughout the experiment, the system removal efficiencies were between 57 and 88% for nitrogen and between 14 and 63% for sulfate. The final effluent showed relatively non-toxicity or moderate toxicity using Daphnia magna as an indicator. Therefore, the overall results showed that the use of a sequential anaerobic-aerobic system is promising for treatment of textile industrial wastewater.     

A new bioreactor for the controlled application of complex mechanical stimuli for cartilage tissue engineering

Mechanical stimuli have been shown to enhance chondrogenesis on both animal and human chondrocytes cultured in vitro. Different mechanical stimuli act simultaneously in vivo in cartilage tissue and their effects have been extensively studied in vitro, although often in a separated manner. A new bioreactor is described where different mechanical stimuli, i.e. shear stress and hydrostatic pressure, can be combined in different ways to study the mechanobiology of tissue engineered cartilage. Shear stress is imposed on cells by forcing the culture medium through the scaffolds, whereas a high hydrostatic pressure up to 15 MPa is generated by pressurizing the culture medium. Fluid-dynamic experimental tests have been performed and successful validation of the bioreactor has been carried out by dynamic culture of tissue-engineered cartilage constructs. The bioreactor system allows the investigation of the combined effects of different mechanical stimuli on the development of engineered cartilage, as well as other possible three-dimensional tissue-engineered constructs.     

Optical distortion in the field of a lithotripter shock wave

The schlieren observation of cavitation phenomena produced in the tail of a lithotripter shock wave has indicated the presence of some interesting features. The images produced appear to indicate that cavitation transients in the field of a shock wave propagate nonsymmetrically; this is not the case. The apparent lack of symmetry exhibited by the primary cavitation transients is due to a complex optical lensing effect, which is brought about by the change in refractive index associated with the pressure profile of the shock wave. Objects seen through or immersed in the shock-wave field of an electromagnetic acoustic transducer, such as cavitation, appear highly distorted because of the strong positive and negative lensing effects of the compression and rarefaction cycles of the shock wave. A modification of the schlieren technique called the scale method has been used to model the distortion introduced by the shock wave and consequently explain the cavitation distortion. The technique has also been used to quantitatively analyze and partially reconstruct the lithotripter shock wave. The combination of schlieren and scale imaging gives more information about the refractive index field and therefore the shock-wave structure itself.     

The influence of porcine growth hormone on muscle fibre characteristics, metabolic potential and meat quality

Treatment of lean female pigs with porcine growth hormone (placebo or 80 μg pGH per kg body weight per day) for 6 weeks from 50 kg to 86 kg body weight did not change the frequency and the percentage area of muscle fibre types (ST, FTa and FTb fibres) and muscle capillarity of M. longissimus dorsi, M. gluteus medius and M. psoas major. The mean fibre cross-sectional area increased 5·3%, albeit nonsignificantly, corresponding to a 6·6% increase in carcass meat. The muscles contained slightly less dry matter and protein, and the lipid content of M. longissimus dorsi decreased 19% after pGH treatment. In the backfat the fatty acid composition changed towards a higher ratio of polyunsaturated to saturated fatty acids. The pH_u of M. longissimus dorsi was unaltered, while the pH₄₅ was reduced by pGH. The muscle glycogen level and the activity of lactate dehydrogenase (LDH), citrate synthetase (CS), and 3-OH-acyl-CoA-dehydrogenase (HAD) of M. longissimus dorsi were unchanged by pGH. The haem pigment, shear force, sarcomere length and eating quality of loin chops, were unaffected by pGH treatment. The results show that pGH treatment did not change the muscle characteristics in a way that affects the meat quality of M. longissimus dorsi in lean female pigs.     

Artificial convolution neural network techniques and applications for lung nodule detection

We have developed a double-matching method and an artificial visual neural network technique for lung nodule detection. This neural network technique is generally applicable to the recognition of medical image pattern in gray scale imaging. The structure of the artificial neural net is a simplified network structure of human vision. The fundamental operation of the artificial neural network is local two-dimensional convolution rather than full connection with weighted multiplication. Weighting coefficients of the convolution kernels are formed by the neural network through backpropagated training. In addition, we modeled radiologists' reading procedures in order to instruct the artificial neural network to recognize the image patterns predefined and those of interest to experts in radiology. We have tested this method for lung nodule detection. The performance studies have shown the potential use of this technique in a clinical setting. This program first performed an initial nodule search with high sensitivity in detecting round objects using a sphere template double-matching technique. The artificial convolution neural network acted as a final classifier to determine whether the suspected image block contains a lung nodule. The total processing time for the automatic detection of lung nodules using both prescan and convolution neural network evaluation was about 15 seconds in a DEC Alpha workstation.