Yield and Functional Properties of Taro Starch as Affected by Ultrasound

Effect of ultrasound pretreatment on yield and functional properties of taro starch was investigated. A three-factor two-level factorial design was employed with treatment time (5 and 10 min), treatment cycle (0.5 and 1), and amplitude of ultrasound (50 and 100 %). Starch yield from ultrasonic treatment varied from 17.45 to 18.97 % compared to 15.29 % in conventional method. The highest yield of 18.97 % was obtained with treatment time 10 min, treatment cycle 0.5, and amplitude 50 %. A significant increase in swelling, solubility, pasting, and texture properties of the ultrasonically extracted starch was observed. A slight decrease in clarity of the starch pastes was also observed after ultrasonic pretreatment, but the differences were not much significant. Freeze-thaw stability of the ultrasonically extracted starches was found to be better compared to starch extracted using conventional method, making them suitable for foods subjected to refrigeration. The whiteness of the ultrasonically extracted starch powders was lower compared to conventionally extracted starch, but the differences were not statistically significant.     

Measuring world city formation – The case of Shanghai

One of the important issues related to world cities studies is the lack of systematic measurement of the formation of world cities. Such a measurement technique would be a useful tool for cities aspiring to attain world city status, especially those cities in Pacific Asia, such as Hong Kong, Singapore, Seoul, and Shanghai. This paper approaches this task by devising a measurement methodology based on quantifiable indicators to generate a World City Index and then uses Shanghai as a case study to test how the city stands compared to 32 current and potential world cities. This paper is a part of the result of the research projects sponsored by the Chinese Academy of Sciences and the National Science Foundation of China with project numbers KZCX2-307 and 40171036.     

Sub-Tenon's anaesthesia: an efficient and safe technique

AIM: To evaluate sub-Tenon's anaesthesia as an alternative to peribulbar anaesthesia. METHODS: 109 consecutive patients listed for various eye operations (including cataract, trabeculectomy, and vitrectomy) under peribulbar anaesthesia were operated on under sub-Tenon's anaesthesia instead. After topical anaesthesia a buttonhole was fashioned through the conjunctiva and Tenon's capsule 10 mm posterior to the limbus. 1.5 ml of lignocaine 2% was then delivered to the posterior sub-Tenon's space using a blunt cannula. The surgical procedure was performed immediately after the completion of the anaesthetic procedure. Chemosis, conjunctival haemorrhage, degree of akinesia, and pain scoring were analysed. RESULTS: There were no anaesthesia related complications. The administration of the block was painless for 99.1% of the patients. In all, 97.3% reported no pain during surgery. There was no akinesia when assessed just after the completion of the block and akinesia was limited when assessed after surgery. Chemosis and conjunctival haemorrhage were frequent but caused no intraoperative problems. CONCLUSION: Sub-Tenon's anaesthesia is an efficient and safe anaesthetic technique. It is a good alternative to peribulbar anaesthesia.     

Task response time for real-time distributed systems with resourcecontentions

An analytic model is proposed for estimating task response times in distributed systems with resource contentions. The model consists of two submodels. The first submodel is an extended queuing network model used for approximating module response times. This submodel is solved by a decomposition technique which reduces the computational complexity by two to three orders of magnitude when compared with a direct approach. The second submodel is a weighted control-flow graph model from which task response time can be obtained by aggregating module response time in accordance with the precedence relationships. Task response times estimated by the analytic model compare closely with simulation results. It is shown that resource contention delays depend on the availability of resources as well as on the invocation rates and response times of the modules that use the resources. The model can be used to study the tradeoffs among module assignments, scheduling policies, interprocessor communications, and resource contentions in distributed processing systems     

Biochemical,Structural, and Genetic Characterization of Tridecaptin A1, an Antagonist of Campylobacter jejuni

Bacillus circulans NRRL B‐30644 (now Paenibacillus terrae) was previously reported to produce SRCAM 1580, a bacteriocin active against the food pathogen Campylobacter jejuni. We have been unable to isolate SRCAM 1580, and did not find any genetic determinants in the genome of this strain. We now report the reassignment of this activity to the lipopeptide tridecaptin A₁. Structural characterization of tridecaptin A₁ was achieved through NMR, MS/MS and GC‐MS studies. The structure was confirmed through the first chemical synthesis of tridecaptin A₁, which also revealed the stereochemistry of the lipid chain. The impact of this stereochemistry on antimicrobial activity was examined. The biosynthetic machinery responsible for tridecaptin production was identified through bioinformatic analyses. P. terrae NRRL B‐30644 also produces paenicidin B, a novel lantibiotic active against Gram‐positive bacteria. MS/MS analyses indicate that this lantibiotic is structurally similar to paenicidin A.     

INTERPHASE MASS TRANSFER FROM SPOUTS CONNECTING THE DISTRIBUTOR PLATE TO FORMING BUBBLES IN FLUIDIZED BEDS

Axial and radial concentration profiles of two tracer gases, methane and naphthalene, have been measured above orifices feeding gas into the base of fluidized beds of diameter 152 mm. The experiments were carried out under hydrodynamic conditions that led to short spouts connecting a central orifice to forming bubbles. Under these conditions mass transfer is shown to be primarily due to convective outflow from the spouts into the dense phase. The mass transfer is predicted with reasonable success by a convective model which uses pressure profiles to help fix hydrodynamic variables and assumes a series of well mixed annular cells in the dense phase.     

Evaporated nanostructured Y2O3:Eu thin films

Europium-doped yttrium oxide (Y2O3:Eu) is a well-known luminescent material that in recent years has been studied in thin-film form. However, to date there has not been a great effort put into altering the nanostructure of these films. A thin-film deposition technique called glancing angle deposition allows for a high degree of control over the nanostructure of the thin film, resulting in thin films with nanostructure geometries ranging from chevron and post to helix. Glancing-angle deposition was used to make europium-doped yttrium oxide thin films with slanted-post nanostructures. Portions of the films were annealed in air at 850 degrees C for 10 hours following deposition. Scanning electron microscopy was used to characterize the nanostructures of the films, while UV laser excitation was used to characterize the photoluminescence properties of the films. The annealed samples exhibited increased photoluminescent responses compared to unannealed samples; however, the porous nanoscale geometry of the films was unaffected. In order to optimize the photoluminescence properties of the films, both the partial pressure of oxygen during film deposition and the level of europium doping in the source material used were varied. Films fabricated from the source material with a greater amount of europium doping had larger photoluminescent responses, while the optimal partial pressure of oxygen during electron-beam evaporation was found to be less than 1.0 x 10(-4) torr.     

Extraction of Speaker Features from Different Stages of DSR Front-Ends for Distributed Speaker Verification

The ETSI has recently published a front-end processing standard for distributed speech recognition systems. The key idea of the standard is to extract the spectral features of speech signals at the front-end terminals so that acoustic distortion caused by communication channels can be avoided. This paper investigates the effect of extracting spectral features from different stages of the front-end processing on the performance of distributed speaker verification systems. A technique that combines handset selectors with stochastic feature transformation is also employed in a back-end speaker verification system to reduce the acoustic mismatch between different handsets. Because the feature vectors obtained from the back-end server are vector quantized, the paper proposes two approaches to adding Gaussian noise to the quantized feature vectors for training the Gaussian mixture speaker models. In one approach, the variances of the Gaussian noise are made dependent on the codeword distance. In another approach, the variances are a function of the distance between some unquantized training vectors and their closest code vector. The HTIMIT corpus was used in the experiments and results based on 150 speakers show that stochastic feature transformation can be added to the back-end server for compensating transducer distortion. It is also found that better verification performance can be achieved when the LMS-based blind equalization in the standard is replaced by stochastic feature transformation.