Differential Global Effects of Selective Estrogen Receptor Modulators on Estrogen Receptor Binding and Transcriptional Regulation

Ph.DDOCTOR OF PHILOSOPH

Characterisation of Physicochemical Properties of Propionylated Corn Starch and Its Application as Stabiliser

A series of propionylated starches with diff erent degrees of substitution (DS) was synthesised and their physicochemical properties and application as a stabiliser were investigated. Starch propionates with moderate DS were prepared by esterifi cation of native corn starch with propionic anhydride. By varying the reaction times of the esterifi cation process, twelve starch propionates with DS of 0.47 to 0.94 were prepared. FTIR and NMR confi rmed the introduction of propionyl groups to the starch. X-ray diff raction patt ern showed reduced crystallinity in the starch propionates. The contact angle was found to increase proportionately with the increase in DS. Swelling power results showed that starch propionates were able to swell more than native corn starch at low temperature (40 °C). Oil-in- -water (O/W) emulsions prepared using starch propionates (DS of 0.64 to 0.86) showed exceptional stability when challenged by centrifugation stress test. These stable O/W emulsions had viscosities in the range of 1236.7–3330.0 mPa·s. In conclusion, moderately substituted short-chain (propionylated) starches could be a promising cold swelling starch, thickener and O/W emulsion stabiliser in food, pharmaceutical and cosmetic industries

Development of Compact P-Band Vector Reflectometer

A compact and low cost portable vector reflectometer is designed for a reliable measurement of reflection coefficient, S11. This reflectometer focuses on return loss measurement of frequency ranges from 450 MHz to 550 MHz. The detection of magnitude and phase is based on the utilization of surface mount Analog Devices AD8302 gain/phase detector. The data acquisition is controlled by using Arduino-Nano 3.0 microcontroller, with the use of two analog to digital converter (ADC) and a digital to analog converter (DAC). One port (Open, short and matched load) calibration technique is used to eliminate systematic errors prior to data acquisition. The evaluation of the reflectometer is done by comparing the result of the measurement to that of vector network analyzer

Multi-targeting aurones with monoamine oxidase and amyloid-beta inhibitory activities: structure-activity relationship and translating multi-potency to neuroprotection

Previously, a series of aurones bearing amine and carbamate functionalities was synthesized and evaluated for their cholinesterase inhibitory activity and drug-like attributes. In the present study, these aurones were evaluated for their multi-targeting properties in two Alzheimer’s disease (AD)-related activities namely, monoamine oxidase (MAO) and amyloid-beta (Aβ) inhibition. Evaluation of the aurones for MAO inhibitory activity disclosed several potent selective inhibitors of MAO-B, particularly those with 6-methoxyl group attached at ring A. Of the different amine moieties attached as side chains, pyrrolidine-bearing aurones were prominent as represented by 2-2, the most potent inhibitor. Evaluation on the Aβ aggregation inhibition identified 4-3 as the best inhibitor with a percentage inhibition comparable to that of a known Aβ inhibitor curcumin. Examination on the neuroprotective ability of the more drug-like aurone 4-3 in two Caenorhabditis elegans neurodegeneration models showed 4-3 to protect the nematodes against both Aβ- and 6-hydroxydopamine-induced toxicities. These new activities further support 4-3 as a promising lead to develop the aurones as potential multipotent agents for neurodegenerative diseases

Modeling and measuring dielectric constants for very thin materials using a coaxial probe

This paper is focused on the non-destructive measurement of the dielectric constants (relative permittivities) of thin dielectric material (0.1-0.5 mm) using an open-ended coaxial probe with an outer diameter of 4.1 mm. Normalized de-embedding and network error calibration procedures were applied to the coaxial probe. The measured reflection coefficients for the thin samples were taken with a vector network analyzer up to 7 GHz, and the calibrated reflection coefficients were converted to relative dielectric constants using an empirical reflection coefficient model. The empirical model was created using the regression method and expressed as a polynomial model, and the coefficients of the model were obtained by fitting the data using the Finite Element Method (FEM)

Physical and Chemical Characterization of Rice Using Microwave and Laboratory Methods

Two main species of cultivated rice in the world are Oryza sativa (Asian rice) and Oryza glaberrima (African rice). The Oryza sativa species, which is grown worldwide, is far more widely utilized compared with the Oryza glaberrima species, which is grown in West Africa. Recently, the annual rice production has reached almost 480 million tonnes, and this demand is expected to rise to 550 million tonnes in 2035. Thus, this increases the need to characterize and maintain the quality of rice and hence to determine the price of rice appropriately. Obviously, modern technologies that can provide fast and accurate measurement are essential in the large-scale industrial rice processing. In this chapter, several technologies and instruments used for rice processing are reviewed. The principle of the measurement for each technology is briefly described. The strength of this chapter is to introduce the application of microwave technology during rice processing, such as rice dying process, rice moisture detection, broken rice measurement and rice insect control. The pros and cons of the microwave method will be discussed in detail. Hence, some standard test laboratory for monitoring of carbohydrate, protein, fat and trace elements content is also described in this chapter

Monitoring moisture content for various kind of tea leaves in drying processes using rf reflectometer-sensor system

This paper presents tea leaves moisture monitoring system based on RF reflectometry techniques. The system was divided into two parts which are the sensor and reflectometer parts. The large coaxial probe was used as a sensor for the system. The reflectometer part plays a role as signal generator and also data acquisition. The reflectometer-sensor system was operated with a graphical user interface at 1.529 GHz at room temperature. The system was able to measure the moisture content of tea leaves ranging 0% m.c to 50% m.c on a wet basis. In this study, up to five kinds of tea leaves bulk were tested. The mean of absolute errors in the moisture measurement for tea leaves was ±2

Fizikalno-kemijska svojstva hidroksipropiliranog kukuruznog škroba te njegova moguća primjena kao stabilizatora emulzija

A series of propionylated starches with diff erent degrees of substitution (DS) was synthesised and their physicochemical properties and application as a stabiliser were investigated. Starch propionates with moderate DS were prepared by esterifi cation of native corn starch with propionic anhydride. By varying the reaction times of the esterification process, twelve starch propionates with DS of 0.47 to 0.94 were prepared. FTIR and NMR confirmed the introduction of propionyl groups to the starch. X-ray diffraction pattern showed reduced crystallinity in the starch propionates. The contact angle was found to increase proportionately with the increase in DS. Swelling power results showed that starch propionates were able to swell more than native corn starch at low temperature (40°C). Oil-in-water (O/W) emulsions prepared using starch propionates (DS of 0.64 to 0.86) showed exceptional stability when challenged by centrifugation stress test. These stable O/W emulsions had viscosities in the range of 1236.7–3330.0 mPa·s. In conclusion, moderately substituted short-chain (propionylated) starches could be a promising cold swelling starch, thickener and O/W emulsion stabiliser in food, pharmaceutical and cosmetic industries.U radu su ispitana fizikalno-kemijska svojstva hidroksipropiliranog škroba različitog stupnja supstitucije, te je istražena mogućnost njegove primjene kao stabilizatora emulzija. Djelomično supstituirani škrob pripremljen je esterifikacijom prirodnog škroba s propilen-oksidom, pri čemu je, ovisno o trajanju reakcije, dobiveno dvanaest uzoraka modificiranog škroba stupnja supstitucije od 0,47 do 0,94. Pomoću spektroskopskih metoda FTIR i NMR potvrđena je prisutnost propionskih skupina u strukturi škroba. Rendgenski je difrakcijski uzorak pokazao smanjenje kristaličnosti škroba. Utvrđeno je da se povećanjem stupnja supstitucije škroba proporcionalno povećao i kontaktni kut. Ispitivanjem bubrenja utvrđeno je da modificirani škrob pri niskoj temperaturi (40 °C) jače bubri od prirodnog škroba. Emulzije modificiranog škroba stupnja supstitucije od 0,64 do 0,86 bile su izuzetno stabilne i nakon centrifugiranja, a njihova viskoznost bila je od 1236,7 do 3330,0 MPa•s. Iz rezultata se može zaključiti da se djelomično supstituirani kratkolančani škrob može upotrijebiti kao sredstvo za zgušnjavanje i stabilizator emulzija pri niskim temperaturama u prehrambenoj, farmaceutskoj i kozmetičkoj industriji

Miniaturization of three-section branch-line coupler using diamond-series stubs microstrip line

A three-section branch-line coupler is miniaturized using diamond-series stubs microstrip lines. The modified coupler is capable of operating from 1.6GHz to 3GHz with a return loss of less than −20 dB, phase imbalance of less than 2.5°, insertion loss and coupling of −4.5±1.5 dB and −2.5±0.5 dB, respectively over the operating range. The bandwidth of the coupler has been extended up to 1.4GHz. In addition, it achieves up to 83.3% size reduction as compared to the conventional three-section coupler. Furthermore, its performance and circuit size are compared with another modified coupler with normal open-stubs microstrip lines. Significantly, this study focuses on analyzing and discussing the effects of diamond structure and number of stubs. Furthermore, the achieved results are superior to the previous studies