Critical analysis of lecturer’s perception on integrating concepts of sustainability in university curricular

Purpose of the study: The growing emphasis on incorporating sustainability concepts in tertiary education has lead higher education institutions in developing countries to infuse sustainability content into their curricula.  The wider purpose of this study is to promote the integration of sustainability concepts within Sri Lankan Universities. The study uncovers and presents the perception of university academics on integrating sustainability in higher education. Methodology: An online-survey was carried out in the month of January, 2019 at the University of Moratuwa, Sri Lanka across four faculties; engineering, architecture, information and technology and business. A descriptive analysis was employed to present the perceptions of the respondents according to different faculties. The obtained data were analyzed using Microsoft excel.  Main Findings: Results revealed, 46.93% have already integrated sustainability concepts while 59.18% are willing to integrate in the near future. 80% have perceived that university curriculum should improve, according to the country’s need while providing particular trainings. 60% felt that knowledge and skills in ICT should be developed and adequate human resources should be deployed prior to incorporate sustainability concepts. Applications of this study: This study is aimed to identify models for mainstreaming sustainability concepts across the tertiary education in Sri Lanka. Novelty/Originality of this study: analyzing the perception of university lecturers on incorporating sustainability concepts across the university curricular, has never conducted in a Sri Lankan university. This is manily conducted to identify the gaps pertaining on intergrating sustainability concepts across university curricular and to identify the barriers exciting for education for sustainable development in Sri Lankan context.

Cell Cycle-Related Cyclin B1 Quantification

To obtain non-relative measures of cell proteins, purified preparations of the same proteins are used as standards in Western blots. We have previously quantified SV40 large T antigen expressed over a several fold range in different cell lines and correlated the average number of molecules to average fluorescence obtained by cytometry and determined cell cycle phase related expression by calculation from multi-parametric cytometry data. Using a modified approach, we report quantification of endogenous cyclin B1 and generation of the cell cycle time related expression profile.Recombinant cyclin B1 was purified from a baculovirus lysate using an antibody affinity column and concentrated. We created fixed cell preparations from nocodazole-treated (high cyclin B1) and serum starved (low cyclin B1) PC3 cells that were either lyophilized (for preservation) or solubilized. The lysates and purified cyclin B1 were subjected to Western blotting; the cell preparations were subjected to cytometry, and fluorescence was correlated to molecules. Three untreated cell lines (K562, HeLa, and RKO) were prepared for cytometry without lyophilization and also prepared for Western blotting. These were quantified by Western blotting and by cytometry using the standard cell preparations.The standard cell preparations had 1.5 x 10(5) to 2.5 x 10(6) molecules of cyclin B1 per cell on average (i.e., 16-fold range). The average coefficient of variation was 24%. Fluorescence varied 12-fold. The relationship between molecules/cell (Western blot) and immunofluorescence (cytometry) was linear (r(2) = 0.87). Average cyclin B1 levels for the three untreated cell lines determined by Western blotting and cytometry agreed within a factor of 2. The non-linear rise in cyclin B1 in S phase was quantified from correlated plots of cyclin B1 and DNA content. The peak levels achieved in G2 were similar despite differences in lineage, growth conditions, and rates of increase through the cell cycle (range: 1.6-2.2 x 10(6) molecules per cell).Net cyclin B1 expression begins in G1 in human somatic cells lines; increases non-linearly with variation in rates of accumulation, but peaks at similar peak values in different cell lines growing under different conditions. This suggests tight quantitative end point control

The APC/C recruits cyclin B1–Cdk1–Cks in prometaphase before D box recognition to control mitotic exit

Prior associations with the APC/C complex during prometaphase makes cyclin B1 a better substrate for the cell cycle–regulating ubiquitin ligase in metaphase (see also a related paper by Di Fiore et al. in this issue)

Understanding the limitations of radiation-induced cell cycle checkpoints

The DNA damage response pathways involve processes of double-strand break (DSB) repair and cell cycle checkpoint control to prevent or limit entry into S phase or mitosis in the presence of unrepaired damage. Checkpoints can function to permanently remove damaged cells from the actively proliferating population but can also halt the cell cycle temporarily to provide time for the repair of DSBs. Although efficient in their ability to limit genomic instability, checkpoints are not foolproof but carry inherent limitations. Recent work has demonstrated that the G1/S checkpoint is slowly activated and allows cells to enter S phase in the presence of unrepaired DSBs for about 4–6 h post irradiation. During this time, only a slowing but not abolition of S-phase entry is observed. The G2/M checkpoint, in contrast, is quickly activated but only responds to a level of 10–20 DSBs such that cells with a low number of DSBs do not initiate the checkpoint or terminate arrest before repair is complete. Here, we discuss the limitations of these checkpoints in the context of the current knowledge of the factors involved. We suggest that the time needed to fully activate G1/S arrest reflects the existence of a restriction point in G1-phase progression. This point has previously been defined as the point when mitogen starvation fails to prevent cells from entering S phase. However, cells that passed the restriction point can respond to DSBs, albeit with reduced efficiency

In-situ mud-concrete as a material for load-bearing walls and sustainable building practices

The world is still struggling to find solutions for the increasing demand for housing with the growing population. To deal with this problem the greater importance has given in researching alternative materials and technologies which can cater sustainable solutions to these evolving demands. However, this materials and technologies must be suitable and appropriate to the local economy, social background and the cultural setting of that country. In the context of innovating sustainable building materials, ‘soil’ receives great attention as an environmental-friendly material, due to its economic affordability, low embodied energy and enhanced natural moisture buffering capacities. Self-compacting Mud-Concrete load-bearing walling (MCW) system is an in-situ cast walling system that combines well-graded soil, cement (stabilizer) and water in their correct proportions. It receives great attention due to its sustainable advantages such as less raw material wastage, low-cost methods, quick construction technology and the low embodied energy consumption. This research presents a detailed analysis of mix design development, system development, thermal performances, long-term performance and cost-effectiveness of self-compacting Mud-Concrete load-bearing walls (MCW). Results demonstrate that optimum usable gravel range is 4.75-32mm in MCW technology. Further, the mix design was finalized as fine - 5% (≤ sieve size 0.425mm), sand - 50 % (sieve size 0.425mm ≤ sand ≤4.75 mm) and gravel - 45% (sieve size 4.75mm ≤ gravel≤ 32mm) with 4% minimum cement of the total dry mix. In addition, optimum 20% of water can use to keep the self-compacting quality of the mix. Grading curves were developed constantly at 4%, 6%, 8% and 10% cement produced the best mix design with standardized methods. Also, the methods were introduced to predict the exact strength of MCW prior to construction. Accelerated erosion tests were conducted to determine the durability of MCW cast of the best mix design and the results satisfied the standard durability requirements under SLS1283. In addition, MCW can be listed as one of the excellent moisture buffering materials according to NORDEST classification system. Optimum lifting height of a wall segment was found as 1200mm which can cast at once without proposing any joints. In every 1200mm height, the proper horizontal joint should be introduced in in-situ cast process and the introduced joint should keep the maximum continuity in between the wall segments. In addition, the results show maximum horizontal shrinkage is 0.23% and maximum vertical shrinkage is 0.22% within 07 days of curing period. Increasing the curing period from 07 days to 14 days, the shrinkage strain was reduced from 0.23% to 0.15%. It depicts that shrinkage strain can reduce in 65% by increasing the curing period for 14 days. Thus 14 days proper curing procedure was recommended to in-situ cast MC wall and the curing should start soon after dismantling the formwork of the wall segments. MCW has 1.2 W/m.K of conductivity, 1440 J/kg.K of specific heat capacity, 1540 kg/m2 of density, 0.366 m2.K/W of R-value and 2.17 W/m2.K of U-Value. MCW acts as a good thermally resistive material due to its thermal mass and insulation characters. Comparatively, MCW has a low embodied energy and life-cycle cost due to the less material wastage, high reusability, fewer labour consumption and quick in-situ construction technologies. Ultimately the research invented a self-compacting in-situ cast load-bearing walling system through Mud-Concrete, which can highly cater to sustainable demands in the construction industry

Mud-concrete block (MCB): mix design & durability characteristics

Mud-Concrete is a novel concept which employs a form of ‘Concrete’ produced using soil, cement and water. The initial concept of developing Mud-Concrete was to incorporate both the strength and durability of concrete into mud-based constructions to introduce a low-cost, load-bearing wall system with easy construction techniques which ensured indoor comfort while minimizing the impact on the environment. Here the fraction of soil is fulfilling the role of aggregate in the material and low quantities of cement will act as a stabilizer. Precisely the usable gravel range and the gravel percentage governs the compressive strength of the material. The considerable high-water amount is used for the hydration of cement and keep the flow of this material. This excessive water amount is enhancing its self-compacting quality, which is capable of self-consolidation, having the ability of passing, filling and being stable without the need of any external forces. Experimental test findings determined the mix proportions of Mud-Concrete block as 4% cement (minimum), fine ≤ 10% (≤ sieve size 0.425 mm), sand 55–60% (sieve size 0.425 mm ≤ sand ≤4.75 mm), gravel 30–35% (sieve size 4.75 mm ≤ gravel≤ 20 mm) and water 18% to 20% from the dry mix. Findings further confirmed that the durability of the Mud-Concrete block satisfied the required durability standards recorded in SLS 1382. Keywords: Mud-Concrete block (MCB), Mix proportion, Fraction of soil, Compressive strength, Durability, Self-compactio

Effect of aggregate percentage on compressive strength of self-compacting In-Situ cast mud - concrete load bearing walls

Mud-Concrete is a novel concept which produces a composite material using soil, cement and water. In the concept of Mud-Concrete technology, sand and metal of concrete are replaced by fine and coarse aggregates of soil. Furthermore, precise gravel percentage governs the strength of Mud-Concrete. Unlike a block when it comes to in-situ cast wall, the walling system could provide much space to both fine and coarse gravel in the mixture, because wall could expand its vertical boundaries. Therefore finding the optimum gravel size and the gravel: sand ratio is important to achieve the best mix for in-situ cast Mud-Concrete load-bearing wall. The experimental results showed that the best gravel (sieve size 4.75mm ≤ gravel≤ 32mm): sand(sieve size 0.425mm ≤ sand ≤4.75 mm): fine (≤ sieve size 0.425mm) ratio for in-situ cast Mud-Concrete wall is 45:50:5 with minimum 4% cement. Further the results indicate the usable gravel range in the soil for Mud-Concrete construction is limited to 35%-55% and sand is limited to 60%-40% with 4% cement. The compressive strength of the Mud-Concrete depends on the particle size distribution of developed soil, optimum gravel size and the optimum gravel: sand ratio of the mix

Energy content of walling materials- a comparison of mud concrete blocks, bricks cabook and cement blocks in tropics

The concept of embodied energy can be used to understand and develop energy saving products or services. By definition the embodied energy is sum of all the types of energy consumed while producing specific product or a service. The embodied energy can be calculated by dividing the total; process of production and measuring each and every process energy consumption. The mud concrete block is a novel ecological walling material. The intention of this paper is to calculate embodied energy and carbon emission, compare in a real world scenario of constructing one square (10ft x10ft) wall of mud concrete block and compare with industrialized walling materials such as brick and cement blocks. The energy consumption of mud concrete block was on account of transport of raw materials (cement) to the factory and the already embedded energy of cement. The cement was a governing raw material in adding energy content to the total embedded energy of mud concrete block. The brick showed comparatively highest embedded energy. And the cement block had intermediate energy content. The Brick production was using more or less sustainable energy sources such as bio mass, bio mass is renewable. But mud concrete block and cement block using non renewable energy sources which can be replaced by renewable energy source

Mud-concrete block construction : community centres for war victim communities in Batticaloa, Sri Lanka

Rejuvenating social interaction within community is an essential factor to survive together for a long time success. Designing buildings for war victim communities is challenging, thus it should be planned with great care, involving the people in the community to the design process, addressing their issues in poverty and fundamental needs through utilizing readily available materials and using locally available cost effective resources. As a new sustainable material, Mud-Concrete block (MCB) technology was introduced to build community centres for selected war victim communities in Batticaloa through ‘UN Re-settling programme’. Thus, different walling materials were introduced to build the community centers in identified areas in Batticaloa. Among those constructions, Mud concrete block (MCB) technology was identified as a highly viable solution which could use locally available soil in construction sites. This paper explores the up-to-date research process of introducing a new sustainable material to restore a war victim community within their context through community architecture

Mud-concrete slab system for sustainable construction

The urgency of global climate emergency has drawn significant attention to the building industry over the last few years. Today, the building sector is responsible for 38% of the world’s greenhouse gas emissions, according to UNEP. 60% -70% of embodied carbon in a conventional column-beam reinforced concrete building is in its floor system. This paper discusses the possibility of constructing an earthen slab system using mud-concrete. It investigates a doubly curved shell structure, working predominantly in compression, to fulfil both environmental and economical demands in the construction industry; reducing the cost and labour expenses nearly 50% compared with that of traditional reinforced concrete slab systems. A 1 m x 1 m prototype mud-concrete slab was constructed to check the potential for modular construction with a square footprint. Poured mud-concrete shell of 50 mm thickness is the primary structural component, while a non-structural mud-concrete filling to a horizontal level 50 mm from apex was used to create a usable floor surface. Masonry mould method was used as the formwork system for the construction considering its cost effectiveness and ease of construction