Modeling of 6 to 4 Switched Reluctance Motor using Coefficient Method and Analytical Method

Electric kick scooter field has become famous this lately, and become another solution for electric vehicle. Switched Reluctance Motor has been choosen as the propulsion system in this application due to the advantages of this motor. Meanwhile, the issue of lack experience in electrical motor design is one of the hollow subjects in machine design field. Through design aspects, the Switched Reluctance motor is developed using a simple technique which is coefficients method. This method is to provide the easiest ways for other non-academic designer for those who has lack experience in motor design. A set of a coefficient to determine motor dimension is being set. Then, this technique will be refered to the existing analytical method to provide a design guideline and to validate this coefficient as the quick references to design the SRM. The aim is not to make a comparison between the methods but intend to provide another easiest solution to design the SRM motor. The modelling has been test using RMxprt tools The expectation from this method is the outcomes will be compatible with existing design.

Changes in rumen protozoal community by condensed tannin fractions of different molecular weights from a Leucaena leucocephala hybrid in vitro

AIMS

To evaluate the effects of condensed tannins (CTs) fractions of differing molecular weights (MWs) from a Leucaena leucocephala hybrid-Rendang on the rumen protozoal community in vitro.

METHODS AND RESULTS

The effects of unfractionated CTs (F0) and CT fractions of different MWs (F1 > F2 > F3 > F4 > F5) on protozoal population and community were evaluated in vitro using rumen microbes and ground guinea grass as the substrate. Higher-MW CT fractions F1 and F2 significantly (P < 0·05) decrease the number of ciliate protozoa. The real-time PCR analysis showed that the total protozoa was significantly (P < 0·05) lower in F0 and all CTs with fractions F1 and F2 having the lowest value. High-throughput sequencing of the partial 18S rRNA gene showed that the genus Entodinium significantly (P < 0·05) decreased with increasing MWs of CT, whereas Anoplodinium-Diplodinium were significantly (P < 0·05) increased. Inclusion of the highest MW CT fraction F1 decreased the relative abundance of the minor genera such as Eudiplodinium and Polyplastron compared to the control and CT fractions F2-F5.

CONCLUSION

CTs of differing MWs could reduce and alter the rumen protozoa population in vitro. This effect was more pronounced for higher-MW CTs.

SIGNIFICANCE AND IMPACT OF THE STUDY

The high MW CTs should be considered as a feed supplement in the ruminant diet to reduce the protozoal population which are known to be associated with methanogens as a means to mitigate methane production in the rumen.

Predicting type 2 diabetes using genetic and environmental risk factors in a multi-ethnic Malaysian cohort

OBJECTIVE

Malaysia has a high and rising prevalence of type 2 diabetes (T2D). While environmental (non-genetic) risk factors for the disease are well established, the role of genetic variations and gene-environment interactions remain understudied in this population. This study aimed to estimate the relative contributions of environmental and genetic risk factors to T2D in Malaysia and also to assess evidence for gene-environment interactions that may explain additional risk variation.

STUDY DESIGN

This was a case-control study including 1604 Malays, 1654 Chinese and 1728 Indians from the Malaysian Cohort Project.

METHODS

The proportion of T2D risk variance explained by known genetic and environmental factors was assessed by fitting multivariable logistic regression models and evaluating McFadden's pseudo R² and the area under the receiver-operating characteristic curve (AUC). Models with and without the genetic risk score (GRS) were compared using the log likelihood ratio Chi-squared test and AUCs. Multiplicative interaction between genetic and environmental risk factors was assessed via logistic regression within and across ancestral groups. Interactions were assessed for the GRS and its 62 constituent variants.

RESULTS

The models including environmental risk factors only had pseudo R² values of 16.5-28.3% and AUC of 0.75-0.83. Incorporating a genetic score aggregating 62 T2D-associated risk variants significantly increased the model fit (likelihood ratio P-value of 2.50 × 10^-4-4.83 × 10^-12) and increased the pseudo R² by about 1-2% and AUC by 1-3%. None of the gene-environment interactions reached significance after multiple testing adjustment, either for the GRS or individual variants. For individual variants, 33 out of 310 tested associations showed nominal statistical significance with 0.001 < P < 0.05.

CONCLUSION

This study suggests that known genetic risk variants contribute a significant but small amount to overall T2D risk variation in Malaysian population groups. If gene-environment interactions involving common genetic variants exist, they are likely of small effect, requiring substantially larger samples for detection.

Cassava root fermented with yeast improved feed digestibility in Brahman beef cattle

Saccharomyces cerevisiae has been used to enhance the protein level of low-protein feedstuffs such as cassava root. In the present study, fresh cassava root was grated and subjected to solid-state fermentation with S. cerevisiae to enhance the protein content. The fermentation process lasted for 21 days, followed by fermentation with yeast for 5 days. The fermented product was called yeast-fermented cassava root (YEFECAR). The YEFECAR was then evaluated as a feed ingredient at 10%, 20% and 30% dry matter in concentrate diet for dry matter intake and nutrient digestibility in non-pregnant female Brahman beef cattle (bodyweight 256 ± 11.5 kg). Four cattle were randomly given four treatments in 4 × 4 Latin square design for 21-day period, including a control diet (without fermented cassava root). Cattle were fed rice straw as roughage. The results showed that while dry matter intake was not significantly different among dietary treatments, average dairy gain tended to increase when fermented cassava root was fed at 20% in the concentrate diet. There were no significant differences in nutrient digestibility among the dietary treatments. However, neutral detergent fibre and acid detergent fibre digestibility showed an increasing trend when fermented cassava root was fed to the cattle. Likewise, fermented cassava root showed no effect on rumen microbial population, although rumen bacterial population and microbial protein tended to increase with YEFECAR addition. It was concluded that yeast-fermented cassava root at 20% in concentrate feed tended to enhance rumen bacteria population and neutral detergent fibre digestibility in cattle.

In vitro rumen fermentation characteristics of goat and sheep supplemented with polyunsaturated fatty acids

An in vitro gas-production study was conducted to compare differences in rumen fermentation characteristics and the effect of supplementation of 4% linseed oil as a source of polyunsaturated fatty acids on the rumen fermentation profile in rumen fluid collected from goats and sheep. Rumen fluid for each species was obtained from two male goats of ~18 months old and two sheep of similar sex and age fed the similar diet containing 30% alfalfa hay and 70% concentrates. The substrate used for the fermentation was alfalfa hay and concentrate mixture (30:70) without (control) and with addition of linseed oil. The experiment was a two (inoculums) × two (oil levels) factorial experiment, with five replicates per treatment, and was repeated once. Rumen fermentation characteristics, including pH, fermentation kinetics, in vitro organic matter digestibility (IVOMD), volatile fatty acid (VFA) production and microbial population were examined. Results of the study showed that gas-production rate (c), IVOMD, VFA production and population of total bacteria and two cellulolytic bacteria (Ruminococus albus and Butyrivibrio fibrisolvens) from rumen fluid of goat were significantly (P &lt; 0.05) higher than those of samples from sheep. Irrespective of sources of inoculums, addition of oil did not affect fermentation capacity, IVOMD and total VFA production. The higher B. fibrisolvens population (associated with bio-hydrogenation) in rumen fluid of goat seems to suggest that polyunsaturated fatty acids are more prone to bio-hydrogention in the rumen of goat than in sheep. This assumption deserves further investigation.

Characterizing the genetic risk for Type 2 diabetes in a Malaysian multi-ethnic cohort

AIMS

To characterize the association with Type 2 diabetes of known Type 2 diabetes risk variants in people in Malaysia of Malay, Chinese and Indian ancestry who participated in the Malaysian Cohort project.

METHODS

We genotyped 1604 people of Malay ancestry (722 cases, 882 controls), 1654 of Chinese ancestry (819 cases, 835 controls) and 1728 of Indian ancestry (851 cases, 877 controls). First, 62 candidate single-nucleotide polymorphisms previously associated with Type 2 diabetes were assessed for association via logistic regression within ancestral groups and then across ancestral groups using a meta-analysis. Second, estimated odds ratios were assessed for excess directional concordance with previously studied populations. Third, a genetic risk score aggregating allele dosage across the candidate single-nucleotide polymorphisms was tested for association within and across ancestral groups.

RESULTS

After Bonferroni correction, seven individual single-nucleotide polymorphisms were associated with Type 2 diabetes in the combined Malaysian sample. We observed a highly significant excess in concordance of effect directions between Malaysian and previously studied populations. The genetic risk score was strongly associated with Type 2 diabetes in all Malaysian groups, explaining from 1.0 to 1.7% of total Type 2 diabetes risk variance.

CONCLUSION

This study suggests there is substantial overlap of the genetic risk alleles underlying Type 2 diabetes in Malaysian and other populations.

Rheological and fractal hydrodynamics of aerobic granules

The structural and hydrodynamic features for granules were characterized using settling experiments, predefined mathematical simulations and ImageJ-particle analyses. This study describes the rheological characterization of these biologically immobilized aggregates under non-Newtonian flows. The second order dimensional analysis defined as D2=1.795 for native clusters and D2=1.099 for dewatered clusters and a characteristic three-dimensional fractal dimension of 2.46 depicts that these relatively porous and differentially permeable fractals had a structural configuration in close proximity with that described for a compact sphere formed via cluster-cluster aggregation. The three-dimensional fractal dimension calculated via settling-fractal correlation, U∝l(D) to characterize immobilized granules validates the quantitative measurements used for describing its structural integrity and aggregate complexity. These results suggest that scaling relationships based on fractal geometry are vital for quantifying the effects of different laminar conditions on the aggregates' morphology and characteristics such as density, porosity, and projected surface area.

Effects of Supplementation of Mulberry (Morus alba) Foliage and Urea-rice Bran as Fermentable Energy and Protein Sources in Sheep Fed Urea-treated Rice Straw Based Diet

A digestibility study was conducted to evaluate the effects of supplementing mulberry foliage and urea rice-bran as a source of fermentable energy and protein to 12 sheep fed diets based on urea-treated rice straw (TRS). The three dietary treatments were: T1, TRS with mulberry; T2, TRS with 50% mulberry replaced with rice bran and urea; and T3, TRS with rice bran and urea. The study was arranged in a completely randomized design with four replications for each treatment. The sheep were fed one of the three diets and the supplements were offered at 1.2% of the body weight (BW) and the TRS was provided ad libitum. There were no differences (p>0.05) among the three treatment groups with respect to dry matter (DM) intake (76.8±4.2 g/kg BW^0.75) and DM, organic matter (OM), and crude protein (CP) digestibility (55.3±1.22; 69.9±0.85; 46.3±1.65% respectively for DM, OM, and CP). The digestibility of fiber (neutral detergent fiber [NDF] and acid detergent fiber) was significantly lower (p<0.05) for T3 (46.2 and 46.6 respectively) compared to T1 (55.8 and 53.7 respectively) and T2 (54.1 and 52.8 respectively). Nitrogen (N) intake by sheep on diet T3 was significantly (p<0.05) higher than sheep fed diet T1. However, N balance did not differ among the three diets (3.0±0.32 g/d). In contrast, the rumen ammonia (NH₃-N) concentrations in sheep fed T2 and T3 were significantly (p<0.05) higher than in sheep fed T1. The NH₃-N concentrations for all three diets were above the critical value required for optimum rumen microbial growth and synthesis. Total volatile fatty acid concentrations were highest (p<0.05) in T1 (120.3 mM), whilst the molar proportion of propionic acid was highest in T3 (36.9%). However, the microbial N supply in sheep fed T1 and T3 was similar but was significantly (p<0.05) higher than for sheep fed T2. It was concluded that mulberry foliage is a potential supplement of fermentable energy and protein for sheep fed TRS based diet. The suggested level of supplementation is 1.2% of BW or 32% of the total diet since it resulted in similar effects on the intake of DM, OM, and NDF, digestibility of DM, OM, and CP, N utilization and microbial supply when compared to rice bran and urea supplementation.

The prevalence and distribution of Brucella melitensis in goats in Malaysia from 2000 to 2009

A study was conducted to describe the prevalence and distribution of zoonotic Brucella melitensis in goats in Peninsular Malaysia. Using serosurveillance data of the last decade (2000-2009) involving 119,799 goats and 3555 farms, the seroprevalence of brucellosis among goats was 0.91% (95% CI=0.86-0.96) and among farms was 7.09% (95% CI=6.27-7.98). The odds of brucellosis was significantly (P<0.05) higher in the later part of the decade, in larger herd size and among the states located in the peninsula as compared to eastern Malaysia. The infection was detected throughout Malaysia but at generally low seroprevalences with states like Perlis that border neighbouring countries having higher seroprevalence of brucellosis than other non-border states.