A comparison of values of organic production obtained from oxygen and C<SUP>14</SUP> methods

Study of marine photosynthesis has been one of the main concerns of marine biological investigations during recent years. With the introduction of radioactive carbon (C14) by Steemann Nielsen (1952) in the measurement of organic production in the sea, this branch of investigation has received considerable fillip. The great sensitivity of this technique has revealed several complex problems regarding factors influencing plant production

Peristaltic-Ciliary Flow of A Casson Fluid through An Inclined Tube

The paper is concerned with the peristaltic-ciliary transport of a viscoplastic fluid (Casson fluid) through an inclined cylindrical tube. The peristalsis-cilia induced motion is analysed in the moving frame of reference under the lubrication approximations. Solutions to the flow characteristics petering to yielded and unyielded regions are obtained. The effects of various physical parameters on the axial velocity, the pumping characteristics, the pressure rise, and the frictional force over one wavelength, along with the trapping phenomenon are presented through graphs. Further, the peristaltic flow and peristaltic-ciliary flow results are compared. It is noticed that the axial velocity and the size of trapping bolus in the unplug flow region decrease with an increase in the yield stress. In addition, the axial velocity and the axial pressure gradient in the peristaltic-ciliary pumping are higher than those in the peristaltic pumping

Design of a 3.3 V analog video line driver with controlled output impedance

The internet revolution has led to the demand for high speed, low cost solutions for providing high bandwidth to the consumers. Cable and DSL systems address these requirements through sophisticated analog and digital signal processing schemes. A key element of the analog front end of such systems is the line driver which interfaces with the transmission medium such as co-axial cable or twisted pair. The line driver is an amplifier that provides the necessary output current to drive the low impedance of the line. The main requirements for design are high output swing, high linearity, matched impedance to the line and power efficiency. These requirements are addressed by a class AB amplifier whose output impedance can be controlled through feedback. The property of this topology is that when the gain is unity, the output resistance of the driver is matched to the line resistance. Unity gain is achieved for varying line conditions through a tuning loop consisting of peak-to-peak detectors and differential difference amplifier. The design is fabricated in 0.5 micron AMI CMOS process technology. For line variations from 65 to 170 ohms, the gain is unity with an error of 3 % and the impedance matching error is 20 % at the worst-case. The linearity is better than 50 dB for a 1.2 V peak-to-peak signal over the signal bandwidth from 10 kHz to 5 MHz and the line resitance range from 65 to 160 ohms

Software Metrics Evaluation Based on Entropy

Software engineering activities in the Industry has come a long way with various improve- ments brought in various stages of the software development life cycle. The complexity of modern software, the commercial constraints and the expectation for high quality products demand the accurate fault prediction based on OO design metrics in the class level in the early stages of software development. The object oriented class metrics are used as quality predictors in the entire OO software development life cycle even when a highly iterative, incremental model or agile software process is employed. Recent research has shown some of the OO design metrics are useful for predicting fault-proneness of classes. In this paper the empirical validation of a set of metrics proposed by Chidamber and Kemerer is performed to assess their ability in predicting the software quality in terms of fault proneness and degradation. We have also proposed the design complexity of object-oriented software with Weighted Methods per Class metric (WMC-CK metric) expressed in terms of Shannon entropy, and error proneness

Note on the organic production in the inshore waters of the Gulf of Mannar

Although considerable data are available on the standing crop of plankton, practically no information is available on the daily production of organic matter in our waters and there fore investigations were started in 1957, with ' a view to measuring the magnitude of production of organic matter by the plankton alga and its fluctuations

Quantitative assessment of the potential fishery resources of the Indian Ocean and adjoining seas

Even -though oceanic fisheries have bccome a major contributing factor in the world production of marine fish, for countries bordering the Indian Ocean which do not have large mechanized fishing fleet capable of operating far away from their ports, the fisheries of shallow-water areas are of primary interes

Standardization of C<SUP>14</SUP> stock solution and filter efficiency in the comparison of primary productivity measurements

Parallel experiments using natural populations were conducted to find out the variability of values of organic production obtained by two different C14 stock solutions, standardization techniques and counting systems as well as the relative efficiency of three types of filters. The results indicate that a uniform method of standardization of stock solution and a careful selection of filters are necessary more than anything else if values of organic production obtained by different workers are to be compared

Anti-Atherogenic Activity of Ethanolic Fraction of Terminalia arjuna Bark on Hypercholesterolemic Rabbits

Atherosclerosis which results from gradual deposition of lipids in medium and large arteries is a leading cause of mortality worldwide. Terminalia arjuna is a herb of Combretaceae family which contains hypolipidemic compounds and flavonoids with high antioxidative properties. This study was conducted to determine the effect of ethanolic fraction of T. arjuna on blood lipids and atherosclerosis in rabbits fed with high fat diet (HFD). Twenty New Zealand rabbits of either sex were randomly divided into five groups: the first two were normal diet group and HFD (21% fat) group and the remaining three groups received high cholesterol diet supplemented with standard drug (Atorvastatin 10 mg kg−1 body weight), T. arjuna ethanolic fraction (100 and 200 mg kg−1 body weight), respectively. The concentration of total cholesterol (TC), low density lipoprotein (LDL) cholesterol, triglycerides (TGs), very low density lipoprotein (VLDL) cholesterol and high density lipoprotein (HDL) cholesterol was determined in rabbits at the start of the experiment, at the 14th, 30th days and at the end of the study. Anti-atherogenic index was calculated from the lipid profile of the rabbits before sacrifice. At the end of the experimental period, the aorta was removed for assessment of atherosclerotic plaques. Results show that T. arjuna significantly decreases TC, LDL and TG levels and increases HDL and lessens atherosclerotic lesion in aorta (P < .05). Hence T. arjuna extract can effectively prevent the progress of atherosclerosis. This is likely due to the effect of T. arjuna on serum lipoproteins and its antioxidant and anti-inflammatory properties