Ripening of fleshy fruit is a differentiation process involving biochemical and biophysical changes that lead to the accumulation of sugars and subsequent changes in tissue texture. Also affected are phenolic compounds, which confer color, flavor/aroma, and resistance to pathogen invasion and adverse environmental conditions. These phenolic compounds, which are the products of branches of the phenylpropanoid pathway, appear to be closely linked to fruit ripening processes. Three key enzymes of the phenylpropanoid pathway, namely phenylalanine ammonia lyase, Omethyltransferase, and cinnamyl alcohol dehydrogenase (CAD) have been reported to modulate various end products including lignin and protect plants against adverse conditions. In addition, peroxidase, the enzyme following CAD in the phenylpropanoid pathway, has also been associated with injury, wound repair, and disease resistance. However, the role of these enzymes in fruit ripening is a matter of only recent investigation and information is lacking on the relationships between phenylpropanoid metabolism and fruit ripening processes. Understanding the role of these enzymes in fruit ripening and their manipulation may possibly be valuable for delineating the regulatory network that controls the expression of ripening genes in fruit. This review elucidates the functional characterization of these key phenylpropanoid biosynthetic enzymes/genes during fruit ripening processes.

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Rapid diagnosis and treatment are important for preventing transmission of Mycobacterium tuberculosis. However, the diagnosis of tuberculosis continues to pose serious problems, mainly because of difficulties in differentiating between patients with active tuberculosis and those with healed lesions, normal mycobacterium boris BCG (Bacillus Calmette Guerin) vaccinated individuals, and unvaccinated Manteux positives. Physicians still rely on conventional methods such as Ziehl-Neelsen (ZN) staining, fluorochrome staining, sputum culture, gastric lavage, and other non-traditional methods. Although the tuberculin test has aided in the diagnosis of tuberculosis for more than 85 years, its interpretation is difficult because sensitization with nontuberculous mycobacteria leads to false-positive tests. There have been numerous unsuccessful attempts to develop clinically useful serodiagnostic kits for tuberculosis. A number of proteinaceous and nonprotein antigens (such as acyltrehaloses and phenolglycolipids) have been explored from time to time for the development of such assays but they have not proved to be clinically useful. It has been difficult to develop an ELISA utilizing a suitable antigen because M. tuberculosis shares a large number of antigenic proteins with other microorganisms that may or may not be pathogenic. With the advent of molecular biology techniques, there have been significant advances in nucleic acid-based amplification and hybridization, which are helping to rectify existing flaws in the diagnosis of tuberculosis. The detection of mycobacterial DNA in clinical samples by polymerase chain reaction (PCR) is a promising approach for the rapid diagnosis of tuberculous infection. However, the PCR results must be corrected for the presence of inhibitors as well as for DNA contamination. In the modern era of genetics, marked by proteomics and genomics, the day is not far off when DNA chip-based hybridization assays will instantly reveal mycobacterial infections.

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In this study, a novel route for the preparation of feedstock filaments for fused deposition modelling from recycled high-density polyethylene (HDPE) and low-density polyethylene (LDPE) waste polymers has been explored. For improving the properties of HDPE/LDPE-recycled polymers, Fe powder has been reinforced through single-screw extrusion. It has been observed that Fe powder (from 0 wt% to 25 wt%) in the LDPE and HDPE matrices has shown increasing trend in melt flow index. Furthermore, Fe powder reinforcement resulted in 36.66% improvement in hardness of reinforced HDPE polymer and 64% in LDPE. Mechanical properties (peak elongation, peak strength, break strength and shore D hardness (SDH)) have been improved significantly with the addition of 6 wt% and 10 wt% reinforcement of Fe powder in the matrix of LDPE and HDPE, respectively. The results of study suggest that morphological properties, such as SDH and percentage porosity, have direct relation with mechanical properties as it has been found that the sample with better mechanical properties was also having high hardness and low porosity. Scanning electron microscopy and energy-dispersive X-ray spectroscopy have been performed on 3D printed functional parts and it has been observed that highly dense texture of HDPE and low surface roughness resulted in better mechanical properties.

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Purpose The purpose of this paper is to fabricate Nylon6-Al-Al2O3-based alternative fused deposition modeling process (FDM) feedstock filament in place of commercial acrylonitrile butadiene styrene (ABS) filament (having required rheological and mechanical properties) for rapid manufacturing (RM) and rapid tooling (RT) applications. The detailed steps for fabrication of alternative FDM feedstock filament (as per field application) with relatively low manufacturing cost and tailor-made properties have been highlighted. Design/methodology/approach The rheological and mechanical suitability of nylon6-Al-Al2O3 feedstock filament has been investigated experimentally. The approach is to predict and incorporate essential properties such as flow rate, flexibility, stiffness and mechanical strength at processing conditions and compared with commercial ABS material. The proportions of various constituents have been varied to modify and improve rheological behavior and mechanical properties of alternative FDM feedstock filament. Findings The alternative material of feed stock filament was successfully developed and loaded in commercial FDM setup without changing any hardware and software. The result of study suggests that the newly developed composite material filament has relatively poor mechanical properties but have highly thermal stability and wear resistant as compared to ABS filament and hence can be used for tailor-made applications. Research limitations/implications In this work, no additive was added for improving the bond formation of metal and polymeric materials. The newly developed filament was prepared on single screw extruder. For more uniform mixing of metal and polymeric materials, further studies may be conducted on twin screw extruder. Also, for the present research work, the testing of newly developed filament has been limited up to mechanical testing, which may be extended to chemical and thermal analysis to understand thermal stability and degradation mechanism of newly developed composite material. Practical implications The proportion of filler material (Al-Al2O3) in Nylon6 matrix was set as a constraint, which was adjusted based upon melt flow index of original equipment manufacturer developed material (ABS), and temperature conditions were available at FDM nozzle (so that hardware and software system of commercial FDM setup need not to be altered). Originality/value The present approach outlined selection, processing, fabrication and testing procedure for alternate feedstock filament, which fulfills the necessary requirements of FDM process and has been customized for RT and RM applications. This work highlights mechanical strength evaluation of feedstock filament (which is necessary before the loading of material in FDM system). The potential applications of this investigation include RM of functional parts, tailor-made grinding tools for dentists and RT of metal matrix composite having complex geometry.