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Antibacterial wound dressings have great importance to reduce wound infections caused by bacteria. In this research work, levofloxacin-loaded silk fibroin and chitosan composite scaffolds were synthesized for effective wound dressing applications. Initially, silk was degummed for extraction of silk fibroin, and it was mixed with chitosan at different ratios. The chitosan and silk fibroin were stirred at room temperature to get soluble and clear gel formation. Afterward, citric acid was poured into the solution and stirred for more 30 min to get a homogeneous solution. The chitosan and silk fibroin composite was dried using a vacuum oven at 40 °C for 48 h. Next, the composite was loaded with levofloxacin HCL for 24 h at room temperature. The prepared composite was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and fourier transform infrared (FTIR) spectroscopy. The antibacterial activity of prepared scaffolds was evaluated by the agar disc diffusion method. The results of FTIR spectroscopy proved that citric acid cross-linked the cross-linked silk fibroin with chitosan. SEM and EDX spectroscopy demonstrated successful loading of levofloxacin onto scaffolds. Moreover, the levofloxacin-loaded scaffold samples confirmed sustained drug release and antibacterial properties. All results demonstrated that the composite scaffolds using silk fibroin and chitosan with an appropriate antibacterial agent could effectively inhibit the growth of bacteria.

In this research article effect of steel fibers on workability and compressive strength of recycled aggregate concrete is presented. Recycled aggregates from demolished waste were used in equal proportion with conventional aggregates. Steel fibers of 1 mm diameter and 25 mm length were used. For preparation of concrete 1:2:4 mix with 0.55 water-cement ratio was used. Workability of each mix was checked by slump cone test. Total of 40 samples were prepared in standard way and cured for 28 days. All the specimens were tested for maximum load in universal testing machine under gradually increasing load at the rate of 0.5 kN/sec. Recorded load was converted into compressive strength. The obtained results showed that slump of the concrete decreased with increase in the dosage of the steel fibers than conventional concrete. Compressive strength was observed 15% and 34% higher than the compressive strength of conventional and recycled aggregate concrete at the steel fiber dosage of 3%. It is evident that although addition of recycled aggregates in concrete reduces the compressive strength but binary blending with steel fibers not only overcomes this loss but shows strength gain with increase in the dosage of the fibers.

In recent years, Building Information Modelling (BIM) is much popularized as construction design approach. It is very useful in providing the necessary information for any project before it is built. BIM implementation has demonstrated several merits; however practitioners have also reported some demerits and barriers which restrict the adoption of BIM in the construction industry. This study assessed the merits, demerits and barrier to implementation of BIM in the construction industry of Pakistan. Data collected form 42 practitioners involved in handling construction BIM based construction projects was analyzed statistically with average index method. The results showed that significant merits of the BIM as perceived by the practitioners are BIM helps in improving quality of Work; BIM is useful in controlling time and cost of the project; and helps in achieving client satisfaction. At the same time, the respondents mentioned BIM adds work for the designer and Interoperability as the significant demerits. Assessment regarding the barriers to BIM showed that top 3 common barriers are: lack of competent staff to operate the software; unawareness of the technology; and not ready to distort normal operational structure. These findings will help the practitioner to take necessary measurement for enhancing the implementation of BIM in the construction industry.

To reduce the consumption of cement in construction industry has been a hot area of consideration now days due to high evolution of CO2 gases during its production. Since decades efforts are made to replace cement with cementitious materials; minerals, agricultural, industrial by products etc. A few are fly ash, ground granulated blast furnace slag, silica fume, rice husk ash etc. These cementitious materials are often adopted as partial replacement of cement. However, their effectiveness and suitability as cementitious material depends upon their properties and the source of the production. Pakistan is an agricultural country and one of the major crops is Rice crop. It produces a substantial amount of rice husk during the processing g of the rice. A substantial amount of Rice Husk Ash (RHA) is produced on the burning of rice husk used as fuel in the rice mills while generating steam for parboiling process of rice grains. This ash causes the environmental problems also if not dumped properly. RHA is believed to have siliceous properties which may be used as supplementary cementitious material in concrete. As the suitability of supplementary cementitious materials is dependent upon the source of rice husk, temperature of burning of husk, its fineness and other properties. This study is focused on to determine the effect of rice husk ash produced by burning of the rice husk obtained from the local rice mills. Experimental investigation carried includes the determination of workability and compressive strength of concrete with different dosage of RHA from 5% to 30% with an increment of 5% tested at 1day, 3days, 7days and 28 days of the age of concrete. The results are compared with corresponding concrete without RHA and tested at the same ages. The results show the reduction in both the parameter; workability and compressive strength due to RHA particularly at its higher dosage beyond 10% by weight of cement.

Construction waste is a global concern among the practitioners and has got attention of the researchers for many years. This issue is serious in construction industry of Pakistan also and various researchers have contributed in addressing it. This paper identified design and procurement related factors and assessed their risk level in causing construction waste. Data was collected through questionnaire survey amongst the practitioners from client consultants and contractors working on construction projects in Karachi and Hyderabad division of the Sind province. A total of 72 completed questionnaire forms were analysed and the results shows that 8 of the 20 factors are highly important factors and fall in the red zone of the risk matrix. It was also observed that last minute client requirements is reported as most important factor in design related issues while “items not in compliance with specification” is the most risk factor in the category of the procurement. Besides these, “last minute client requirements” and “Mistakes in quantity surveys” are the key factors which have significant effect on project cost. The findings of this study will be helpful for the practitioner to improve design and procurement quality for controlling the waste generation.

Background: The aim of the present review is to provide basic knowledge regarding the treatment of Coronavirus via medicinal plants. Coronavirus (COVID-19, SARS-CoV, and MERS-CoV) as a viral pneumonia causative agent, has infected thousands of people in China and worldwide. Currently, there is no specific medicine or vaccine available that can treat or prevent this virus and this has posed a severe threat to human health; therefore, there is an urgent need to develop a novel drug or anticoronavirus vaccine. However, natural compounds to treat coronaviruses are the most effective alternative and complementary therapies due to their diverse range of biological and therapeutic properties. Methods: We performed an open-ended, English restricted search of Scopus database, Web of Science, and Pubmed for all available literature from Jan-March, 2020, using terms related to phytochemical compounds, medicinal plants and coronavirus. Results: The view on anti-coronavirus (anti-CoV) activity in the plant-derived phytochemicals and medicinal plants gives a strong base to develop a novel treatment employing these compounds for coronavirus. Various phytochemicals and medicinal plant extracts have been revised and are considered as potential anti-CoV agents for effective control of the virus and future drug development. Herein, we discuss some important plants (Scutellaria baicalensis, Psorothamnus arborescens, Glycyrrhiza radix, Glycyrrhiza uralensis, Lycoris radiate, Phyllanthus emblica, Camellia sinensis, Hyptis atrorubens Poit, Fraxinus sieboldiana, Erigeron breviscapus, Citri Reticulatae Pericarpium, Amaranthus tricolor, Phaseolus vulgaris, Rheum palmatum, Curcuma longa and Myrica cerifera) that have emerged to have broad-spectrum antiviral activity. Conclusion: Nigella sativa has potent anti-SARS-CoV activity and it might be a useful source for developing novel antiviral therapies for coronavirus.

Experimental results are presented for a new dieless strip drawing process in which conventional wedge-shaped dies have been replaced by a reduction unit having a stepped rectangular cavity. The smallest cavity dimensions are larger than those of the incoming strip, thus eliminating the problem of die friction and consequential tool wear.In this novel process, the strip is passed through a chamber filled with polymer melt and then pulled through the reduction unit. The strip material is deformed due to the combined effects of shear drag and the hydrodynamic pressure generated by the converging flow of the polymer melt.Experiments were carried out in which the process parameters such as the unit geometry, speed and polymer melt temperature and hence viscosity were varied and the hydrodynamic pressure, reduction in strip size and drawing load were measured. Initial experiments were carried out by using copper strip and low-density polyethylene at two different melt temperatures. Results from experiments showed that a reduction in area of strip of more than 10 per cent could be achieved in a single pass.The Newtonian analysis presented by the authors in reference (9) is modified to incorporate the critical shear stress limit of the polymer melt and the non-linear strain-hardening property of the strip material.