Integrated approach as sustainable environment technique for managing construction waste : a review

The construction industry was reported as a major consumer of natural resources worldwide. Almost 60% of the natural resources consumed by this industry have caused a lot of environmental impacts on humans and the environment. Among the impacts were the disruption of human water sources, changes in the biological ecosystem and disruption of the food supply chain among biological factors. Countries around the world have enforced several laws and regulations. Apart from that, waste management technologies were formulated by government agencies and the world’s researchers were among initiatives to minimise the waste generation rate. Several technologies, such as recycling and recovery technologies were highlighted to be very efficient in minimising the waste accumulation rate. This paper discussed an integrated concept for managing construction waste in a sustainable manner. The integrated approach has adopted the reuse method, central sorting facilities, recycling facilities, thermal treatment facilities and disposal facilities. Implementations of these integrated approaches were able to save the world’s raw materials and natural energy sources as well as reducing the impacts of pollution on the environment

Understanding patient health-seeking behaviour to optimise the uptake of cataract surgery in rural Kenya, Zambia and Uganda: findings from a multisite qualitative study

Background Cataract is a major cause of visual impairment globally, affecting 15.2 million people who are blind, and another 78.8 million who have moderate or severe visual impairment. This study was designed to explore factors that influence the uptake of surgery offered to patients with operable cataract in a free-of-charge, community-based eye health programme. Methods Focus group discussions and in-depth interviews were conducted with patients and healthcare providers in rural Zambia, Kenya and Uganda during 2018–2019. We identified participants using purposive sampling. Thematic analysis was conducted using a combination of an inductive and deductive team-based approach. Results Participants consisted of 131 healthcare providers and 294 patients. Two-thirds of patients had been operated on for cataract. Two major themes emerged: (1) surgery enablers, including a desire to regain control of their lives, the positive testimonies of others, family support, as well as free surgery, medication and food; and (2) barriers to surgery, including cultural and social factors, as well as the inadequacies of the healthcare delivery system. Conclusions Cultural, social and health system realities impact decisions made by patients about cataract surgery uptake. This study highlights the importance of demand segmentation and improving the quality of services, based on patients’ expectations and needs, as strategies for increasing cataract surgery uptake

Characteristics of Al-Alloy/Seashell (SESB) Composites in Acidic and Alkaline Environments

The corrosion behaviour of Al-alloy/Seashell (SeSh) composites in the acidic and alkaline environment was investigated in this study. Fifteen Aluminum alloy composites samples were produced using stir casting technology by varying the amount of reinforcement (1.5, 3.0, 4.5, 6.0, 7.5 wt%) and particle size (100, 150, 200 µm) of milled SeSh in the Aluminium alloy matrix. The corrosion rate was determined using a weight loss technique after 18 days of immersion at an interval of 72 hours. It was observed that 6.0 wt% of the 100 µm reinforced Aluminium alloy had the best corrosion resistance in acidic and alkaline environments. In general, the reinforced Al-alloy had better corrosion resistance when compared with the unreinforced samples. Analyses of the results show that aluminum alloy seashell composites exhibited better resistance to corrosion in the alkaline environment than the acidic environment

3-D Nanofibrous Electrospun Multilayered Construct is an Alternative ECM Mimicking Scaffold

Abstract Extra cellular matrix (ECM) is a natural cell environment, possesses complicated nano-and macroarchitecture. Mimicking this three-dimensional (3-D) web is a challenge in the modern tissue engineering. This study examined the application of a novel 3-D construct, produced by multilayered organization of electrospun nanofiber membranes, for human bone marrow-derived mesenchymal stem cells (hMSCs) support. The hMSCs were seeded on an electrospun scaffold composed of poly e-caproloactone (PCL) and collagen (COL) (1:1), and cultured in a dynamic flow bioreactor prior to in vivo implantation. Cell viability after seeding was analyzed by AlamarBlue TM Assay. At the various stages of experiment, cell morphology was examined by histology, scanning electron microscopy (SEM) and confocal microscopy

Acceptability of HIV self-sampling kits (TINY vial) among people of black African ethnicity in the UK: a qualitative study

Background: Increasing routine HIV testing among key populations is a public health imperative, so improving access to acceptable testing options for those in need is a priority. Despite increasing targeted distribution and uptake of HIV self-sampling kits (SSKs) among men who have sex with men in the UK, little is known about why targeted SSK interventions for black African users are not as wide-spread or well-used. This paper addresses this key gap, offering insight into why some groups may be less likely than others to adopt certain types of SSK interventions in particular contexts. These data were collected during the development phase of a larger study to explore the feasibility and acceptability of targeted distribution of SSKs to black African people. Methods: We undertook 6 focus groups with members of the public who self-identified as black African (n = 48), 6 groups with specialists providing HIV and social services to black African people (n = 53), and interviews with HIV specialist consultants and policy-makers (n = 9). Framework analysis was undertaken, using inductive and deductive analysis to develop and check themes. Results: We found three valuable components of targeted SSK interventions for this population: the use of settings and technologies that increase choice and autonomy; targeted offers of HIV testing that preserve privacy and do not exacerbate HIV stigma; and ensuring that the specific kit being used (in this case, the TINY vial) is perceived as simple and reliable. Conclusions: This unique and rigorous research offers insights into participants’ views on SSK interventions, offering key considerations when targeting this population.. Given the plethora of HIV testing options, our work demonstrates that those commissioning and delivering SSK interventions will need to clarify (for users and providers) how each kit type and intervention design adds value. Most significantly, these findings demonstrate that without a strong locus of control over their own circumstances and personal information, black African people are less likely to feel that they can pursue an HIV test that is safe and secure. Thus, where profound social inequalities persist, so will inequalities in HIV testing uptake – by any means

A study on wear failure analysis of tungsten carbide hardfacing on carbon steel blade in a digester tank

This paper addresses wear failure analysis of tungsten carbide (WC) hardfacing on a carbon steel blade known as the continuous digester blade (CD blade). The CD blade was placed in a digester tank to mix ilmenite ore with sulphuric acid as part of a production process. Tungsten carbide hardfacing was applied on the CD blade to improve its wear resistance while the CD blade was exposed to an abrasive and acidic environment. Failure analysis was car-ried out on the hardfaced CD blade in order to improve its wear resistance and lifetime. A thickness and hardness comparison study was conducted on worn and unworn specimens from the CD blades. The carbide distribution along with elemental composition analysis of the hardfaced CD blade specimens was examined using scanning electron microscopy and energy-dispersive spectroscopy. The investigation revealed that an inconsistent hardfacing thickness was welded around the CD blade. Minimum coating thickness was found at the edges of the blade surfaces causing failure to the blades as the bare carbon steel blades were exposed to the mixed environment. The wear resistance of the CD blade can be improved by distributing the carbide uniformly on the hardfaced coating. Applying extra coating coverage at the critical edge will prevent the exposure of bare carbon steel blade, thus increasing the CD blade lifetime

On the conservation of the slow conformational dynamics within the amino acid kinase family: NAGK the paradigm

N-Acetyl-L-Glutamate Kinase (NAGK) is the structural paradigm for examining the catalytic mechanisms and dynamics of amino acid kinase family members. Given that the slow conformational dynamics of the NAGK (at the microseconds time scale or slower) may be rate-limiting, it is of importance to assess the mechanisms of the most cooperative modes of motion intrinsically accessible to this enzyme. Here, we present the results from normal mode analysis using an elastic network model representation, which shows that the conformational mechanisms for substrate binding by NAGK strongly correlate with the intrinsic dynamics of the enzyme in the unbound form. We further analyzed the potential mechanisms of allosteric signalling within NAGK using a Markov model for network communication. Comparative analysis of the dynamics of family members strongly suggests that the low-frequency modes of motion and the associated intramolecular couplings that establish signal transduction are highly conserved among family members, in support of the paradigm sequence→structure→dynamics→function © 2010 Marcos et al