An Alternative Electrode System for Monitoring Belousov-Zhabotinsky Chemical Oscillations

The capability of copper-platinum (Cu/Pt) electrode system as a BelousovZhabotinsky (BZ) chemical oscillation monitor was compared with that of the normally used SCE/Pt electrode system, by testing it on three BZ systems, which were obtained by varying the oscillator in the combination bromate, oscillator and malonic acid. The oscillators, used separately, were cerium(IV), manganese(II) and ferroin [iron (II)-1,10- phenanthroline complex].Cu/Pt electrode gave essentially identical values of oscillation characteristics (oscillation period, peak potential, induction period, peak width) except peak potentials. This indicated that the Cu/Pt electrode system would be more useful than the SCE/Pt electrode system (which had chloride leakage problem), in electrical applications of chemical oscillations, such as electrical switches, which would depend only on the on/off frequency

A Potential Model for Chemical Oscillations

Oscillation characteristics: induction period, oscillation period, peak potential, and total oscillation time of Belousov-Zhabotinsky systems, which consisted of bromate - oscillator [Ce4+ or Mn2+ or ferroin] - malonic acid were deter- mined using SCE/Pt and Cu/Pt electrodes. The solution potential requirements for appearance of chemical oscillations were determined by finding the concentra- tion limits of the reactants, bromate and malonic acid, and measuring the corres-ponding solution reduction potentials. A chemical oscillation model was proposed

The Effect of DDT Residue on the Composition and Digestibility of Alfalfa Hay

DDT (2,2 bis (p-chlorophenyl) 1,1,1,-trichloroethane) was first synthesized in 1874 by Seidler in Switzerland, however, its effectiveness as an insecticide was not known until about 1942. The active principle was first known as G.H.B. (Gesarol-Neccid Base): but in 1943 DDT was suggested as an abbreviation for Dichlore Diphenyl Trichloroethane (Kaaegie, 1946). In fact DDT, as a powerful insecticide is one of the developments made during World War II. The importance of DDT in the control of the common insect enemies of mankind, such as mosquitoes, flies, moths, and many agricultural insect pests is realized more day by day. Many studies have been conducted to determine the uses, toxisity and residual effectiveness of DDT. However, the nutritive value of DDT dusted feedstuffs has not been investigated heretofore. During recent years, in the west, alfalfa seed and hay production has declined as a result of injuries caused by certain species of insects such as lygus bage and alfalfa weevil. DDT has been used successfully to control these insect pests. Because of this fact there is a need for more information on the chemical composition, digestibility and metabolisable energy content of DDT treated alfalfa hay

Assessment of risk factors for breast and ovarian cancer in UMS students

Cancer is a major public health problem and the third leading cause of death in Malaysia . Breast and ovarian cancers are the first and fourth most common cancer among women in Peninsular Malaysia. Our aim is to assess the risk factors in healthy young adult female students from UMS and will act as an input for further prevention of breast and ovarian cancer. Total 278 Medical and Nursing students from Faculty of Medicine and Health Sciences were participate in this study. Assessing the hereditary risk factor, total 12.34% gives positive result for history of breast tumour in first degree relatives and for ovarian tumour total 1.8% gives positive results in first degree relatives. An overall mutation frequency of 2.3%, in woman who had at least one first-degree relative with breast cancer diagnosed at age <50 years ( Hartge et al. (1999) . The lifetime risk of breast cancer among female mutation carriers was 82% and lifetime risks of ovarian cancer were 54% for BRCA1 and 23% for BRCA2 mutation carriers. Risk reducing options are available to women with a strong family history of breast and ovarian cancer. These options include high-risk screening, chemoprevention, and prophylactic surgery. In our study, 63.7% is not meeting with WHO recommendation for Metabolic Equivalent Task (MET) and remaining 36.3% meets WHO recommendation. By using International Physical Activity Questionnaire (IPQA)Score protocol,only 2.6 % of Medical students showed Health Enhancing Physical Activity (HEPA) active,36.4 % showed minimally active and 60.9% showed inactive. Among nursing students only 5.5% showed HEPA active, 35.4% showed minimally active and 59.1% are inactive. Primary prevention through behavioural and life style modification is a cost-effective means of preventing the large burden cancer has on societies world-wide

Tobacco smoking among school adolescents in Northern Sabah

Tobacco smoking in adolescent age group has become a major public health concern as it is one of the major risk factors for non-communicable diseases leading to burden of adverse health effects in their later life. Those who start smoking tobacco at an early age are more likely to develop nicotine addiction and continue smoking throughout their adulthood. The general objective of the study was to determine the prevalence of tobacco smoking, their initiation and perception towards tobacco smoking among school adolescents in Kudat District, Sabah State, Malaysia. It was a school based cross sectional descriptive study which employed a two-staged stratified random sampling method and used self-administered structured questionnaire for data collection. A total of 257 students aged between 15 to 19 years old from two upper secondary schools participated in the study. This study revealed that (26.6%) were ever smokers and (8.6%) were current smokers. The earliest age of started smoking was 7 years old and 9 years old among male and female ever smokers respectively. Majority of the respondents perceived that smoking was a bad habit which would cause environmental pollution and harmful effects on health. The most common reasons to start smoking among ever smokers were peer pressures, curiosity and experimenting and to relieve the feeling of pressured and stress. Among the current smokers, 86.4%had ever attempted to quit smoking but they failed to stop smoking because they thought smoking could give feeling pleasure (50%), relieve their anxiety or craving (27.3%) and because of peer pressures (22.7%). The findings suggested that although tobacco smoking prevalence among school adolescents in Kudat was comparatively lower than that of national prevalence reported by GYTS, there is still need for early interventions with holistic approach to prevent them from initiation and to help them for cessation of tobacco smoking

Influence of Surcharge Loading, Retained Soil and Restrained Soil on Design of Diaphragm Wall

Many different types of embedded retaining wall are constructed due to the increasing demands. In Yangon, Myanmar is encountered deep excavation problem. Many buildings are damaged due to excavation of adjacent building. Therefore, embedded retaining wall as excavation support system is necessary to be sustainable buildings. There are important that influence of surcharge loading, retained soil and restrained soil on design of embedded retaining wall.  In this paper, diaphragm Wall is emphasized and solved using soil structure interaction analysis. Behaviour of diaphragm Wall wall is based on various factors. Consider with natural and increasing of shear strength parameter of retained and restrained soils to get the level of the dredge line is stiff soil and various distances from wall to surcharge. Sites are located in urban setting, there are near building and separately from main structure. This project involves the construction of 5 m depth retaining wall. In case study (A) retained soils is soft, medium (low) clay, restrained soil is mostly cohesive soil. There are medium (low), stiff, medium, hard soil layers.  In case studies (B to H) are increasing shear strength parameter of retained soil and restrained soil. All cases are considered with various distances from wall to surcharge. According to the soil conditions and distance from wall to surcharge, Wall depth, horizontal and vertical movement of ground and wall deflection are described. When retained and restrained soil reach stiff condition, then ground movement and wall deflection reach acceptable limit and wall depth become more safe and economical condition

Hemoglobinopathies and Malaria Infection in Myanmar

Screening for the incidences of hemoglobinopathies (Hb E, α-thalassemia (thal) and β-thal) and malaria infection was done in 131 healthy volunteers with no clinical symptoms in Shan State in Myanmar. The group consisted of 71 females and 60 males ranging in age from 16 to 46 years old. The analysis of hemoglobin was carried out using high performance liquid chromatography (HPLC) and isoelectric focusing (IEF), and DNA analysis was done by polymerase chain reaction (PCR)-electrophoresis. The incidences of carriers of Hb E, α-thal and β-thal were 17.6%, 7.6% and 0.8%, respectively. The thal genotypes observed were -α^, which is an α-thal-2 mutation, and CD17A→T, which is β^0-thal mutation. Both are common mutations in Myanmar. There were only three (2.3%) carriers of two malaria parasites, Plasmodium falciparum (Pf) and Plasmodium vivax (Pv); namely one female carrier of Pf and two male carriers of Pv. Although it was suspected that the incidence of subjects infected with malaria would be high, there was comparatively small number of cases. This may be the reason why the blood sample collection from the volunteers was done during the dry season which is not the breeding season for malaria mosquitos

Influencing factors for cholera and diarrhoea: Water sanitation and hygiene in impoverished rural villages of Beluran District, Sabah, Malaysia

The lower percentage of water, sanitation and hygiene are the root causes of diarrhoea and cholera. Cholera is a sudden onset of acute watery diarrhoea which can progress to severe dehydration and death if untreated. The current pandemic, Vibrio Cholera O1 started in 1961. This study explores water, sanitation, hygiene and cholera and diarrhoea in three affected villages of Beluran District, Sabah Malaysia to support effective and timely public health intervention. This cross sectional study uses purposive sampling. All (114) households were interviewed and household water samples collected. The study reported lower coverage improved sanitation facilities (35.3% to 52.3%), no latrine at home (37% to 63%), improved water supply (52% to 60%), and prevalence of hand washing after toilet (57% - 74%). For water quality, Ecoli was present in household water (32% to 37%) but Vibrio cholerae was not isolated in any of the water samples tested. Statistically significant associations were found for; 1) occupation−non-agriculture and unimproved sanitation facility and 2) house ownership and correct knowledge of ORS preparation. Predictors for household water quality were: latrine at home, and improved household toilet. Aggressive strategies to improve water supply, sanitation and hygiene−hand washing after toilet−were recommended for future prevention of cholera and diarrhoea in the affected area