71 research outputs found
Virtual material science laboratory manual / Muhammad Nazri Nayan and Mohammad Azizi Abdullah
No full textThis Virtual Material Science laboratory manual is basically a computer programming project to computerized conventional material science laboratory manual. This indicates that all the experimental scripts can able to be displayed in interactive manner using computer as a platform rather than paper handout. This project considers various aspects in the process of developing the computer program. Start from collecting related theories and experiments involved in the Material Science subject, selection of computer programming language and lastly designing the user interface and display of the program. Progression of this new virtual laboratory manual is also considered in the research. Virtual laboratory manual is a web programming and up to date programming language such as HTML, JavaScript and ASP is implemented to fulfill the needs and requirements of this project. This project can set a new development trend of the virtual laboratory programming project to the faculty
Discerning the variation in fungal-treated wheat straw as ruminant feed
No full textThe use of white-rot fungi in bioprocessing of lignocellulosic biomass such as wheat straw into valuable ruminant feed ingredients is promising. Fungi are capable of degrading lignin – a cell wall polymer that negatively affects ruminal degradability of the biomass. For this purpose, fungi, such as C. subvermispora, P. eryngii and L. edodes, have been identified as potential species. The vast availability of strains of these species, as well various wheat straw types and conditions lead to four main research questions: (1) Do strains of the same fungal species differ in their extent of lignocellulose degradation and the subsequent improvement in the ruminal degradability of wheat straw? (2) How do high potential strains/species vary in utilizing a certain nutrient, such as protein? (3) Do different fungal strains/species possess unique delignification mechanisms? (4) Do various wheat straw types have effects on how fungi degrade the cell wall components? As a start to the screening trial, in Chapter 2, the bioprocessing capabilities of two strains of C. subvermispora, CS1 and CS2, were compared. Both fungi were capable of selectively degrading lignin and improve in vitro gas production (IVGP) of wheat straw, with CS1 showing a higher potential than CS2. The two fungi also differed in their growth pattern and enzymatic activities, as well as in the degree of selectivity in lignin degradation. There was no correlation between the activities of the lignin-degrading enzymes and the extent of lignin degradation, indicating that more complex mechanisms are involved in modifying the cell wall. In Chapter 3, the IVGP was used as a decisive screening parameter for the best performing fungi. A number of strains of the fungal species C. subvermispora, P. eryngii and L. edodes were screened based of their IVGPs. All strains that belonged to the same species showed a distinctive pattern of growth and changes in the pH of substrate. Nonetheless, large variations of their bioprocessing capabilities were observed. Out of the 32 fungal strains studied, 17 strains showed a significantly higher (P C. subvermispora); PE6, PE2 and PE3 (P. eryngii); LE8, LE7 and LE10 (L. edodes). Two high-ranked strains for each species in Chapter 3 were subjected to three follow-up studies on variation in protein solubilization and modification of lignin structures. In Chapter 4, different fractions of crude protein (CP) and in vitro protein fermentation of wheat straw treated with six fungal strains (2 strains per species) were evaluated. All fungal strains caused a relative enrichment of the CP content (23.3 to 30.9%) in wheat straw. There was no quantitative difference in the total amount of CP among different fungal-treated straws. However, the CP fraction provided a unique insight into the variation among fungi in solubilizing protein. The results showed that fungi increased the soluble protein fractions and decreased the cell wall bound protein. Only wheat straw treated with P. eryngii and L. edodes strains resulted in a higher protein availability for fermentation in the rumen (30.2 to 47.1%). C. subvermispora strains on the other hand, did not improve the protein availability. To validate the established relationship between IVGP and the cell wall contents, determined using the Van Soest method (Procedure A), more specific analyses of the cell wall (Procedure B) were used in Chapter 5. In Procedure B, pyrolysis (Py-GC/MS) and alditol-acetates were used to determine Py-lignin and carbohydrates content, respectively. Procedure A showed a higher correlation coefficient of lignin/carbohydrate to the IVGP, compared to Procedure B (Pearson’s r of -0.84 vs. -0.69, respectively). The large differences between methods indicate disparities in the mass recovery of cell wall components, which complicates the understanding of degradation of cell wall components and its effect on IVGP. Procedure A is more indicative of the cell wall solubility – which explained the IVGP well, rather than indicating the actual cell wall degradation by fungi. The more specific Procedure B better elucidates the structure, which helps with the understanding of variations among fungal strains in modifying the cell wall. As for the cellulose (and glucan) contents, neither procedure resulted in an accurate quantification of the cellulose due to interference of fungal biomass. A contribution of pure fungal biomass to the total IVGP was expected, since it showed higher IVGP than its corresponding treated wheat straw. Hence, specific analyses of the lignin and carbohydrates contents are required for accurate description of the ruminal degradability of wheat straw. The combined pyrolysis-GC/MS and 2D-nuclear magnetic resonance (NMR) analysis in Chapter 6, revealed fundamentally different delignification mechanisms among fungal species. It was proposed that the cleavage of Cβ-O-aryl linkages as the main mechanism for C. subvermispora, besides Cα-Cβ cleavage. While the predominant mechanism for L. edodes and P. eryngii was through the cleavage of Cα-Cβ linkages. In Chapter 7, the persistence of the high potential strains of C. subvermispora and L. edodes in improving the ruminal degradability of wheat straw of different maturities and cultivars was studied. The degradation of lignin by both fungi was more pronounced on mature straw (MS3; ~89.0%), compared to the MS1 (~70.7%). In contrast, cellulose was less degraded on MS3 compared to MS1 (~8.3 vs. 14.6%). The ‘preference’ of fungi in the delignification of a more mature straw was confirmed by Py-GC/MS. A higher abundance of the S-unit compounds was found on MS3, which made the mature straw more susceptible to fungal attack. A variable extent of degradation of lignin (47 to 93.5%) was observed when both fungi were grown on different straw cultivars. The high potential strains of C. subvermispora and L. edodes were able to improve the IVGP of various straw types. However, the magnitude of IVGP was only affected by different cultivars, but not by straw maturity. Research presented in this thesis discerned the biological variation of different fungal strains/species in modifying the cell wall contents, producing variable effects on the ruminal degradability of wheat straw. The new finding on the capability of some fungi to solubilize protein from the cell wall is important, which could pave the way for more advanced and in-depth studies in the future. The high potential strains selected in Chapter 3 were proven capable of improving the nutritive value of various batches of wheat straw, indicating the potential of bringing this eco-friendly pretreatment method into practice.</p
Collaborative workplace writing: insights from experienced workplace writers / Latisha Asmaak Shafie and Surina Nayan
No full textCollaborative workplace writing is a collective writing that combines the expertise of a group of workplace writers to produce well- written pieces of writing. It is more efficient than single-author writing at workplaces. However, collaborative workplace writing is challenging as the writers have their challenges, schedules and aspirations. Therefore, insights from experienced collaborative workplace writers assist novice workplace writers who do not know what to expect when they write collaboratively. The study is a qualitative multiple case study to investigate the collaborative workplace writing skills and collaborative technologies used by four experienced collaborative workplace writers. The data were collected were collected through semi-structured interview. The study investigates the characteristics of experienced collaborative writers, the collaborative writing skills and the collaborative technologies. The findings suggested that experienced collaborative writers are subject matter experts, independent learners, 21st - century learning skills and adaptability skills. Additionally, the findings show that collaborative writers use a framework for collaborative writing in their writing projects. The study also reveals that collaborative technologies are necessities to enrich the writers’ collaborative writin
Performance and metabolomic urinalysis of heat-stressed dairy goat fed diet supplemented with soybean oil
No full textHeat stress negatively affects the animal production that could result in devastating economic lossess. The benefits of supplementing dietary fats to the animals under such conditions have been extensively reviewed. However, there is a lack of information on the effects of soybean oil supplementation on the performance of the animals, particularly under heat stress conditions. In addition, the application of the state-of-the-art technology such as 1H NMR-based metabolomics to study the fundamental physiological processes in animal production study is still few. The first experiment was carried out to assess the productive performance, thermoregulatory functions and milk parameters of heat stressed Murciano-Granadina goats fed diets supplemented with soybean oil. Meanwhile, the second experiment was conducted to identify possible metabolite markers as a result of the heat stress and soybean oil supplementation. The results from the first experiment showed that the heat stressed goats lost an average of 3.14 ± 2.30 kg of their body weight compared to the thermoneutral group that gained an average of 3.19 ± 2.62 kg of body weight. They also had a 39.1% lower dry matter intake (DMI), consumed 46.8% more water and produce 9.7% less milk compared to the thermoneutral group goats. Under heat stress conditions, there were significant correlations between temperature humidity index (THI) values and the water consumption (r = 0.66; P0.05) negative correlations between THI and DMI (r = -0.19) and milk production (r = -0.36). No significant effect (P>0.05) of soybean oil supplementation and its interaction with thermal conditions were found in any productive performance. Nonetheless, milk from supplemented animals were 23.2 and 1.6% higher in milk fat and protein content, respectively, besides 18.1 and 14.0% higher feed efficiency under heat stress and thermoneutral conditions,respectively. In the second experiment, partial least square – discriminant analysis (PLS-DA) model was only found significant (P<0.01) for heat stress vs.thermoneutral treatment groups comparison. Several metabolites of importance were identified which involved in various physiological response of animals to heat stress,such as increased harmful gut microbiota activity (hippurate), increased catecholamines and neurotransmitter activities (L-phenylalanine, glycine) and decreased degradation of energy-related metabolites (acetate, isoleucine and glutamate). The urine sample of the heat stressed goats was also shown to have a higher 3-hydroxybutyrate and lower creatinine, which are important in assessing the energy status of the animals. Despite the lack statistical evidence, soybean oil supplementation was shown to have beneficial physiologic effects on the animals,especially during heat stress with the higher creatinine level, and lower isoleucine and glutamate found in the urine. The present study has proved the adverse effects of heat stress on animal production. There was also economic and physiologic benefit of soybean oil supplementation despite no significant result on the productive performance was observed. Meanwhile, metabolite assessment provides a deeper understanding on the physiological response of the animals towards environment and feeding interventions
Optimization of watermelon waste as a bulking agent for sustainable co-composting of livestock manures using response surface methodology
No full textGlobal human population growth has resulted in significant intensive agricultural activity, posing substantial challenges to waste management and environmental conservation. Watermelon waste (WW), chicken manure (CM) and horse manure (HM) are among the main contributors to agricultural waste due to their abundant waste production. This study aims to manage the daily production of these wastes by utilizing WW as a bulking agent in the co-composting of CM and HM. Response surface methodology (RSM) was employed to analyze the effects of four independent factors: HM:CM composition, particle size, composting period, and bulking agent amount. Thirty treatments were developed using central composite design and in-vessel composting reactors were employed to study the relationship between the factors involved and compost physicochemical quality parameters. The results demonstrated significant effects on organic matter (OM), nitrogen (N), potassium (K), dry matter, moisture content, bulk density, and pH, while the carbon-to-nitrogen ratio (C/N) and phosphorus level were not affected. The optimized co-composting conditions obtained from RSM were 75:25 for HM:CM composition (%), 0.5 cm for particle size, 40 days for composting period, and 10% of WW, resulting in a compost with 61% OM, 2.5% N, and 2.5% K. These optimal conditions agreed closely with the predicted values; root mean square prediction error (RMSPE) was less than 0.50, revealing the success of RSM in determining optimal process parameters and developing models for predicting responses. Our study demonstrated that WW as a bulking agent in the co-composting of CM and HM has significantly enhanced the organic matter and nutrient levels of the final compost product. Copyright © 2024 Nurin, Tee, Chin, Zainudin and Nayan
String Diagrams for Physical Duoidal Categories
No full textWe introduce string diagrams for physical duoidal categories (normal -symmetric duoidal categories): they consist of string diagrams with wires forming a zigzag-free partial order and order-preserving nodes whose inputs and outputs form intervals.26 pages, 11 figures. The author thanks Nayan Rajesh for pointing out a mistake on a previous version of Definition 8.
The influence of N2 flow rate on Ar and Ti Emission in high-pressure magnetron sputtering system plasma
No full textVariation in the solubilization of crude protein in wheat straw by different white-rot fungi
No full textBesides their unique ability to depolymerize cell wall components, white-rot fungi are known to assimilate nitrogenous compounds from substrates. This modification may change protein solubility and fermentation in the rumen. To investigate this, the crude protein (CP) in fungal treated wheat straw (3 fungal species, 2 strains each) was fractioned according to the Cornell Net Carbohydrate and Protein System (CNCPS) and assessed for in vitro protein fermentation using a modified gas production technique (IVGPN). Results showed that fungi increased fraction A (instantaneously soluble CP; ∼2.6 times) and B1 (rapidly degradable; ∼1.2 times); and decreased the slowly degradable fraction B3 (∼41.6%) and unavailable fraction C (∼48.3%). The IVGPN of straw treated with Ceriporiopsis subvermispora strains were not different to the control, but increased by 30.2 to 47.1% in Pleurotus eryngii and Lentinula edodes strains. The IVGPN was significantly (P < 0.01) correlated to all fractions of CP, except fraction B1 and B2 (intermediately degradable). All fungi also increased the arginine (∼56%) and lysine (∼15%) contents. This study shows the importance of assessing the protein solubilization by different fungal strains, which can uncover unique mechanisms in the cell wall depolymerization
Prospects and feasibility of fungal pretreatment of agricultural biomass for ruminant feeding
No full textIn recent years, the use of white-rot fungi as a pretreatment method to improve the nutritive value of agricultural biomass as ruminant feed, has received a substantial attention. However, there are several issues that need to be addressed for a successful application of this method. One of the issues is the inevitable variation in the nutritive values of the fungal-treated biomass. This paper reviews our recent works on validating the variation in the nutritive values of biomass treated with different fungal species. The general aims of these studies are: (1) to study the variability among different fungal species (and strains) in improving the nutritive value of the same batch of wheat straw; and (2) to assess the capabilities of selected fungi to improve different batches and types of wheat straw. A large variation of ruminal degradability – measured as in vitro gas production, IVGP), was observed, even for different strains of the same fungal species. The IVGP for different strains of Ceriporiopsis subvermispora ranged from 205.5 to 317.8 mL/g organic matter (OM), while the IVGP ranges for the strains of Lentinula edodes and Pleurotus eryngii were 183.5–306.6 ml/g OM) and 206.6–267.0 ml/g OM, respectively. A high potential fungus, strain CS1 of C. subvermispora consistently improved the IVGP of different batches and types of wheat straw by 27.7–47.6%. The variation in the nutritive value of fungal-treated biomass is evident. However, this issue can be overcome by using the right fungal strains with an optimal culture and growth conditions. More research needs to be done to make it an attractive substitute to physico-chemical methods. Here, we also put forward our manifestation on the future prospects of fungal pretreatment for ruminant feeding
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