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In this work, novel biocompatible and reduction-responsive soft hydrogels were formulated from norbornene (Nb)-functionalized carboxymethyl cellulose (CMCNb). To cross-link the CMC-Nb via a highly bioorthogonal inverse electron demand Diels-Alder (IEDDA) reaction, we employed a water-soluble and reduction-responsive diselenide-based cross-linker possessing two terminal tetrazine (Tz) groups with varying molar concentrations (Nb/Tz molar ratios of 10/10, 10/05, and 10/2.5). The N

In this exploratory study, the effects of nano silica (NS) on the properties of self-compacting pastes (SCPs) incorporated with superabsorbent polymer (SAP) have been investigated. NS was added to cement pastes, containing SAP, in varying amounts of 1%, 2% and 3%. SAP were found out to be successful in mitigating shrinkage in all formulations; however they were more effective in mixes without super-plasticizers (SPs). SAP particles reduced the fluidity, increased the air content and also reduced strength slightly due to the formation of macro-pores. NS was beneficial in improving the hydration attributes by increasing the mechanical strength and refining the microstructure. The denser microstructure of the NS modified pastes compensated for the macro pore formation associated with SAP incorporation, leading to strength increase. With NS, there was better bonding of the SAP particles in the matrix. The reduced Ca(OH)2 content in NS modified samples showed increased pozzolanic activity associated with NS in cement pastes.

Cough acoustics contain multitudes of vital information about pathomorphological alterations in the respiratory system. Reliable and accurate detection of cough events by investigating the underlying cough latent features and disease diagnosis can play an indispensable role in revitalizing the healthcare practices. The recent application of Artificial Intelligence (AI) and advances of ubiquitous computing for respiratory disease prediction has created an auspicious trend and myriad of future possibilities in the medical domain. In particular, there is an expeditiously emerging trend of Machine learning (ML) and Deep Learning (DL)-based diagnostic algorithms exploiting cough signatures. The enormous body of literature on cough-based AI algorithms demonstrate that these models can play a significant role for detecting the onset of a specific respiratory disease. However, it is pertinent to collect the information from all relevant studies in an exhaustive manner for the medical experts and AI scientists to analyze the decisive role of AI/ML. This survey offers a comprehensive overview of the cough data-driven ML/DL detection and preliminary diagnosis frameworks, along with a detailed list of significant features. We investigate the mechanism that causes cough and the latent cough features of the respiratory modalities. We also analyze the customized cough monitoring application, and their AI- powered recognition algorithms. Challenges and prospective future research directions to develop practical, robust, and ubiquitous solutions are also discussed in detail.

This experimental study explores the feasibility of the development of eco-friendly self-compacting cementitious systems, utilizing wood waste sawdust (SD), for sustainable building construction. Two different gradations of SD viz-a-viz, coarse SD (CSD) and fine SD (FSD) were used in modifying neat Portland cement paste system as partial replacement of cement, in various weight fractions of 2%, 5%, and 7%. The fresh and hardened state properties of SD modified paste were determined. The results indicated that despite the strength reduction with SD addition in cement paste (strength decrease of 11%–34% was observed with SD addition), the resulting shrinkage strain is greatly reduced owing to the higher water absorption of SD particles thus increasing the water demand, to maintain self-compactibility, as well. The reduction in shrinkage of SD modified pastes was significant, with a reduction range of 45%–80%, as compared to control sample. Density and unit weight of the developed pastes were also reduced. The ability of SD to absorb water and releasing it later, thus providing moisture for cement hydration, suggests that SD has the potential to serve as an internal curing agent in self-compacting cementitious systems. Utilizing SD in cementitious binders may, then, not only promote sustainable development, but also lead to more durable infrastructures.

This paper shows the response of self-compacting paste systems (SCPs) containing botanical Acacia Modesta (AM) gum, a natural organic ooze-out of an indigenous tree called Phulai, as an admixture. The gum being different in its nature and origin, exhibited different results from Acacia Nilotica gum powder when used in SCPs. AM gum powder was characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared Spectroscopy (FTIR). The self-compacting paste systems (SCPs) containing 0.25%, 0.5%, 0.75% and 1% AM gum powder were tested for super-plasticizer (SP) demand, flow, viscosity, air content (in fresh state), density, total linear early shrinkage, calorimetry and both short-term (28-day) and long-term (90-day) compressive strengths. SCPs with AM gum powder showed a considerable decrease in total shrinkage, a reduction in density values, an increase in fresh state viscosity. AM gum powder also had a retarding effect on setting times of the respective gum modified SCPs. Moreover, the electrical resistivity of samples containing AM increased tremendously indicating change in the microstructure of the gum modified SCP systems. It became clear that different types of Acacia gums when incorporated in SCPs gave different responses and should be used with complete understanding. Therefore, AM gum in cementitious systems offers many potential areas for application and further future research work. The AM gum powder may be used for reducing shrinkage in SCP systems, establishing internal curing inside the SCCS, for enhancing the viscosity of the cementitious systems and for producing slightly porous energy efficient cementitious systems.

Cement is a source of anthropogenic emissions ensuing environmental concerns and susceptible to crack under stresses. For mitigating the durability concerns, a bio-influenced effective microorganisms technology (EMs) has been employed in the cementitious composites. In the present research, the effect of EMs on the properties of self-compacting and conventional cementitious composites was explored using three types of EMs (EM1®, EMC® and EMX-Ceramics®) with three different of cements (CEMI, CEMIII and Calcium Aluminate cement). Taguchi approach of experimental design was implemented for optimization of formulations. L18 (21 × 37) orthogonal array was selected based on influencing factors namely w/c ratio, cement type, EMs type and EMs percentage replacement. Specimens were casted and cured in air, moisture and desiccator. Forensic inspections were performed to monitor the growth of hydration products and precipitation of bio-calcite precipitate. Energy performance of EMs modified composites was also analyzed using ECOTECT. Experimental results were analyzed statistically using analysis of variance (ANOVA). The analysis revealed that w/c and EM % replacements as the most governing parameters in response modification of cement composites. The 4% EM replacement was determined to be the optimal percentage in refining the fresh and hardened state response of cementitious systems. Forensics endorsed the microstructural refinements as a result of bio-precipitate, contributing in the increase of mechanical properties and reduction in 27% cooling loads. Moreover, theoretical equations were proposed for prediction and optimization of mix design based on Taguchi approach using extensive regressions.

Effective Microorganism technology (EMT) is of Japanese origin and has found useful applications in agriculture and water treatment works. This study reports the response of self-compacting paste systems with the addition of a mixture containing three micro-organisms namely lactic acid bacteria, photosynthetic bacteria and yeast all present in a suitable liquid medium. Two types of Effective Microorganisms (EMs) consortia, EM-Light (EML) having light brown color and low microbial cell concentration and EM-Dark (EMD) having dark brown color with high microbial cell concentration in a suitable liquid were used to study a total of seven self-compacting paste (SCP) formulations. These seven formulations include a control formulation and six EM modified SCP formulations containing 5, 10 and 15% (by wright content of cement) of both EM liquid consortia. The results showed that both EM consortia modified the plastic viscosity, delayed setting times and hydration kinetics, modified volume stability, reduced water absorption of SCP systems in hardened state and enhanced the compressive strength of SCP systems. Especially strength of SCPs with EMD seem to depend on fresh density of the paste to a large extent while with EML it shows different response. An increase of 26% in strength was observed compared to the control formulation with 15% EMD amendment at similar water-cement ratio along with a reduction in water absorption of hardened SCPs which may be attributed to the refinement in microstructure obtained by the production of calcium carbonate predominantly as a result of the reaction between microorganisms and calcium hydroxide. Scanning electron microscopy (SEM) and XRD results also suggest improvements in strengths of SCPs due to calcite (calcium carbonate).

This research characterizes the gum obtained as a natural organic ooze-out from Acacia Nilotica trees, indigenously known as “Keekar”, through Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared Spectroscopy (FTIR) experimental techniques. It reports the response of self-consolidating paste systems (SCPs) containing Acacia Nilotica Gum (AG) in powdered form in ratios of 0.33%, 0.66% and 1% by weight of cement. The results are of interest to construction and civil engineering professionals and showed that AG enhanced the viscosity of SCPs which in turn improves their stability. Also, AG addition increased the water demand, setting times and early age expansion of SCPs while the heat of hydration, density and compressive strength got reduced. Reduction in density is attributed to incorporation of air voids and this may be exploited in energy efficient infills of buildings and possible improved freeze-thaw resistance. Most of the lost compressive strength due to AG incorporation was regained with the addition of Secondary Raw Materials (SRMs) including fly ash (FA) and limestone powder (LSP).

A study is reported on a two lane in-service pre-stressed concrete bridge having susceptible vibrations under service traffic conditions. The bridge was 1300 ft long with thirteen simple pre- cast post tensioned spans resting on in-situ bridge piers. The client reported significant vibrations under service loads and requested a solution. The bridge did not have a top wearing surface. Bridge design drawings were provided. The methodology of health assessment included the visual inspection followed by analysis with the help of drawings provided by the client. The records of concrete strengths along with prestressing protocols were missing. The static and dynamic bridge response using static and moving three different loaded vehicles (over loaded tractor trolley, unloaded 5 Axle vehicle loaded trailer and loaded 5 axle trailers) was monitored. Core samples from the bridge deck were taken. NDT, Digital half-cell and electrical resistivity readings were taken at various locations of bridge. The results indicated some design inadequacies, faulty construction methodologies, improper maintenance and lack of awareness even by the professionals to deal with such structures. The remedial measures were suggested in terms of strengthening and maintenance of bridge.

A series of aqueous solutions of poly(vinyl alcohol) of various commercial products were prepared and applied onto the surfaces of cotton and blends of cotton/polyester fabrics. Fourier transform infrared spectrophotometer was used to confirm the molecular structure of the polyvinyl alcohol used. Performance tests such as colorfastness to rubbing (dry and wet) and colorfastness to washing were determined. The controlling variables affecting the performance properties of the finished substrate such as post-treatment with poly(vinyl alcohol) of various commercial trades, concentration and dilutions were studied. Crocking, washing and hue change of the treated dyed and printed fabrics is accompanied by the formation of semi-inter-penetrated network structure due to the presence of the hydroxyl (–OH) groups which make feasible to a number of grafting and physical cross linking reactions of polymer backbone.

Because concrete and mortars both contain aggregate phase, it may be expected that the trend of results obtained from mortar formulations should be similar to those of concrete or vice versa. Many researchers have used either limestone powder (LSP) or fly-ash (FA) in self-compacting concrete systems. However the present study shows that using either of these secondary raw materials (SRMs) in self-compacting mortar systems does not produce an optimized response. However mixing LSP and FA in suitable proportions and then using this blended SRM enhances the response of self-compacting mortar systems as both FA and LSP seem to complement the properties of each other especially the negative ones. The formulations contain two base SRMs (limestone powder and fly-ash) and in others these two basic SRMs have been replaced at 20% of their mass by some other SRMs or their combinations. Parameters like flow, strength, microstructure, relative water absorption and early volume stability of self-compacting mortar systems have been studied. The results indicate that self-compacting mortars using blended secondary raw material of limestone powder and fly-ash had an improved overall response than those using either of them.

A series of poly(vinyl alcohol) of different commercial grades were prepared and applied onto the surfaces of cotton and blends of cotton/polyester fibers. The molecular structure was confirmed using Fourier Transform Infrared spectroscopy. Physicochemical properties such as viscosity and solid contents (%) were determined and discussed. Factors affecting the performance properties of the finished substrate such as post-treatment with poly(vinyl alcohol) of different grades, concentration and dilutions were studied. Fixation of the poly(vinyl alcohol) onto/or within the cellulose structure is accompanied by the formation of semi-inter-penetrated network structure thereby enhancing the association as well as providing very high stiffness. The results revealed that applications of poly(vinyl alcohol) on the textile fabrics in the finishing processes enables to enhance the stiffness as well as helps to improve its pilling resistance.