Lucas based el-gamal cryptosystem in the elliptic curve group over finite field under lenstras attack

This paper reports on a Lenstra’s attack against the Lucas based El-Gamal Cryptosystem in the elliptic curve group over finite field. Lenstra’s attack is an attack to recover the secret factor of the order of elliptic curve group from a faulty signature. Results show that the success of the Lenstra’s attack depend on cryptographic algorithm implementation practice rather than the weakness of the cryptosystem itsel

Characterization and classification of whole-grain rice based on rapid visco analyzer (RVA) pasting profile

Classification of whole grain rice using only amylose content is not practical to predict starch viscosity for end product recommendation. This study aims to characterize and categorize whole-grain rice based on pasting profile of Rapid Visco Analyzer (RVA). The rice cultivars showed a wide range of peak viscosity (89.98 to 280.95 RVU), hold viscosity (59.97 to 211.56 RVU), breakdown viscosity (-0.33 to 130.67 RVU), final viscosity (111.25 to 390.75 RVU), setback viscosity (-44.47 to 205.67 RVU) and pasting temperature (74.17 - 91.15oC). Stability ratio and final viscosity explained 68.8% of total variance in the RVA profiles. The rice cultivars could be grouped into high (> 0.95), medium (0.65-0.95) and low ( 300 RVU), medium (140 - 250 RVU) and low (< 140 RVU) final viscosity. The classification could serve as a basis for effective rice selection according to functional properties of whole grain rice

Safe use of chlorpyrifos for insect pest management in leaf mustard (Brassica juncea (L) Coss.)

Leaf or Chinese mustard (Brassica juncea L. Coss.) is one of the main vegetables consumed in Malaysia. Farmers widely use chlorpyrifos as active ingredients for insect pest control in leaf mustard crops, and repeated applications are a common practice. Thus, studies are needed to determine residue levels with respect to time or frequency of application to ensure residue levels at harvest are below the international MRL. An experiment was conducted in a greenhouse at the share farm in Universiti Putra Malaysia Bintulu Campus to study leaf residue levels of the insecticide chlorpyrifos used to control insect pests in leaf mustard (Brassica juncea L. Coss.). There were three treatments including an untreated control in four replicates. Chlorpyrifos was applied at 0.46, 0.92 kg a.i./ha at 3 weeks after sowing. Leaf samples for residue analysis were harvested at 8, 14 and 20 days after treatment. Chlorpyrifos residue levels in the leaf samples were determined by HPLC (JASCO LC-2000 plus series), fitted with an Inertsil ODS-3 (5 µm, 4 mm×50 mm length) column with PDA-wavelength detector. Insect damage assessment was determined at 13 and 18 days after treatment to evaluate effectiveness of the treatments. Insect damage was significantly higher in the control compared to insecticide treatments. Chlorpyrifos residue was not detected in all leaf samples at 8, 14 and 20 days after treatment. This suggests that a single application of chlorpyrifos at 3 weeks after planting did not pose any residue problems in leaves harvested after 4 weeks from planting, and thus were safe for consumption

Cryptographic attack on Lucas based cryptosystems using chinese remainder theorem

Lenstra’s attack uses Chinese remainder theorem as a tool and requires a faulty signature to be successful. This paper reports on the security responses of fourth and sixth order Lucas based (LUC4,6) cryptosystem under the Lenstra’s attack as compared to the other two Lucas based cryptosystems such as LUC and LUC3 cryptosystems. All the Lucas based cryptosystems were exposed mathematically to the Lenstra’s attack using Chinese Remainder Theorem and Dickson polynomial. Result shows that the possibility for successful Lenstra’s attack is less against LUC4,6 cryptosystem than LUC3 and LUC cryptosystems. Current study concludes that LUC4,6 cryptosystem is more secure than LUC and LUC3 cryptosystems in sustaining against Lenstra’s attack

Development of biodegradable plastic composite blends based on sago derived starch and natural rubber

Polyethylene is a widely used packaging material, but its non-biodegradable nature can lead to waste disposal problems. This increases the concern in research and development of biodegradable plastics from natural resource as alternatives to petroleum-derived plastics. In this study, biodegradable plastic composites were prepared by blending thermoplastic starch with natural rubber in the present of glycerol as plasticizer. Local sago starch was cast with 0.5 to 10% of natural rubber to prepare the bioplastic. The products were characterized by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), water absorption test, biodegradable test, hydrolysis test, and mechanical analysis. Meanwhile, composite with natural rubber latex was increased from 0.5 to 10% showing that the melting temperature is in the range of 120 to 150 °C, but with no significant difference. The water absorption characteristics, biodegradability, and tensile strength decreased by 11.21%, 30.18%, and 20.733 MPa, respectively. However, the elongation at break was increased from 26.67 to 503.3%. The findings of this study showed that sago starch has a great potential in bioplastic production with good miscibility and compatibility

Johnson noise of CdX-P3HT nanocomposite

Johnson noise for nanocomposite thin films has been analyzed to study its potential and reliability as an element for electronic devices. Nanocomposite thin films face many challenges such as dispersion of nanoparticles in the matrix that hamper it suitability, competency and performance for potential devices. In this paper, the Johnson noise and current density-voltage has been measured for thin films fabricated through two different methods. The first type of nanocomposite is CdS or CdSe nanoparticles were impregnated in conjugated polymer, P3HT through gas exposure. The second type is by physically mixing CdS or CdSe quantum dots into P3HT. Both nanocomposites employ Langmuir layer as the basis of the film. The Johnson noise for both types of thin films are relatively small, less than 1× 10 -27 A 2 /Hz for frequency more than 10 Hz, regardless of quantum dots or nanoparticles loading. The JV results show nanoparticles impregnated inside the P3HT have better electrical performance. Thus, the nanocomposites fabricated through gas exposure have better potential to be utilized in electronic devices

Genotyping of Sarawak rice cultivars using microsatellite markers

Genetic diversity of 53 Sarawak rice cultivars, originating from Southern Sarawak, was assessed using 54 microsatellite markers. Initial polymorphism detection was conducted using 54 primer pairs distributed on 12 rice chromosomes. Polymorphic markers were chosen from the initial screening results in order to obtain microsatellite marker panels that can differentiate the rice cultivars undertaken in the study. The chosen microsatellite marker panel consisted of RM1, RM240, RM489, RM252, RM413, RM204, RM11, RM404, RM316, RM271, RM206, and RM19, with one representative from each chromosome. A total of 43 alleles were detected with an average of 3.58 alleles per locus. The polymorphism information content (PIC) values obtained from the microsatellite marker panels ranged from 0.306 to 0.730, with an average of 0.622. The Unweighted Pair Group Method with Arithmetic Mean (UPGMA) dendrogram (r = 0.789) revealed 2 major groups with 6 sub-clusters and the wide range of similarity values (0.24-1.0) obtained showed a high degree of diversity among the cultivars. The results suggest microsatellite markers as a useful tool for the estimation of genetic diversity and cultivar differentiation and present invaluable genetic information for future breeding and association mapping efforts

Effect of parboiling on in vitro physiological antioxidant capacity of brown rice

Parboiling process has been widely implemented in brown rice processing, but its effect on in vitro physiological antioxidant capacity of brown rice was not known. In this study, an in vitro method simulating the human physiological conditions was used to investigate the effect of parboiling on antioxidant capacity of brown rice in three Bario rice varieties. In this method, bacterial inocula were prepared from rat cecal contents. Results showed that parboiling process gave significant impacts on in vitro physiological antioxidant capacity of brown rice. The process improved total phenolic content at small intestine (Adan Halus), DPPH scavenging activity at both small and large intestines (Adan Halus and Bario Merah) and ferrous ion-chelating activity at large intestine (Bario Hitam). However, changes in antioxidant capacity were variety dependent, possibly due to different bran pigmentation. These suggested that parboiling process could improve physiological antioxidant capacity with in vitro simulation at small and large intestines by selecting a suitable rice variety and parboiled brown rice could offer good antioxidant properties to maintain physiological health

Physiochemical characteristics of alcohol-acid modified sago and rice starches

Native starch has limited applications. It has many disadvantages in industrial applications such as insolubility in cold water, loss of viscosity, and thickening power after cooking. In order to overcome these disadvantages, native starch is modified through physical, chemical or biotechnological techniques. Starch is one of the major components in sago but it had not been well explored to the same degree as maize or potato starch especially in the starch modification processes. In this study, the effects of alcohol-acid treatment on the physiochemical characteristics of sago and rice starches were investigated. Sago and rice starches were hydrolysed for 2 hours at 25 ºC with hydrochloric acid in the presence of methanol, ethanol, and 2-propanol. They were characterized according to their granular structure, solubility, amylose content, gelatinization temperature and functional group. After treatment, presence of internal fissures or cavities was observed. The degradation activity increased corresponding to carbon number of alcohol. Results also showed that the gelatinization onset temperature (To), conclusion temperature (Tc) and peak temperature (Tp) increased with increasing carbon number of the alcohol. The Tp of starches was negatively correlated to the amylose content of starches before and after treatment (r2 = 0.954 for rice and 0.945 for sago). Solubility increased profoundly after treatment and the degree of hydrolysis increased with the increase in carbon number of the alcohol. Rice starch was less soluble than sago starch due to higher amylose content. Rice starch was also found to be less susceptible to alcohol-acid degradation than sago starch, and the unstable properties of native starches improved with 50% increase in solubility at temperature 80 ºC. Results concluded that alcohol-acid treatment of sago and rice starches provide a wide range of modified starches with better solubility, higher gelatinization temperatures but lower in amylose content

Impact of phytic acid on nutrient bioaccessibility and antioxidant properties of dehusked rice

Whole grains consumption promotes health benefits, but demonstrates controversial impacts from phytic acid in meeting requirements of good health. Therefore, this study was aimed to determine the nutrient bioaccessibility and antioxidant properties of rice cultivars named BAdan^ or BBario^ and deduce the nutritional impact of phytic acid. Majority of the dehusked rice in the collection showed an acceptable level of in-vitro starch digestibility and in-vitro protein digestibility, but were poor in antioxidant properties and bioaccessibility of minerals (Ca, Fe and Zn). The drawbacks identified in the rice cultivars were due to relatively high phytic acid content (2420.6±94.6 mg/100 g) and low phenolic content (152.39± 18.84 μg GAE/g). The relationship between phytic acid content and mineral bioaccessibility was strongest in calcium (r=0.60), followed by iron (r=0.40) and zinc (r=0.27). Phytic acid content did not significantly correlate with in-vitro starch digestibility and in-vitro protein digestibility but showed a weak relationship with antioxidant properties. These suggest that phytic acid could significantly impair the mineral bioaccessibility of dehusked rice, and also act as an important antioxidant in nonpigmented rice. Bario rice cultivars offered dehusked rice with wide range of in-vitro digestibility of starch and protein, and also pigmented rice as a good source of antioxidants. However, there is a need to reduce phytic acid content in dehusked rice for improved mineral bioaccessibility among Bario rice cultivars