A Comparative Study of Deep Learning Model and Simple Prediction Charts in Construction Noise Prediction

Construction noise monitoring is crucial to assess the impacts of construction noise on the workers and surroundings. However, the existing noise prediction methods are time-consuming in which required laborious work for the computation of noise levels. This study aims to assess the accuracy and reliability of deep learning model (DL) that adopted stochastic modelling and artificial neural network (ANN) in construction noise prediction. The artificial neural network was trained with the output of stochastic modelling. The outcome of noise level prediction using simple prediction chart (SPC) and DL model was discussed and compared to 3 case studies. The case studies were conducted at construction sites located in Semenyih, Selangor, Malaysia. The results of DL model showed high accuracy of predicted noise levels along with an absolute difference of less than 2.3 dBA. Besides, the predicted noise levels are reliable as the R-squared value is higher than 0.992. On that account, DL model is proved to be reliable and accurate in noise level prediction and it has the potential to be utilized as a managerial tool to monitor construction noise more effectively

Calcium alginate hydrogel beads with high stiffness and extended dissolution behaviour

Alginate hydrogel bead has been widely explored as a vehicle for controlled delivery application due to its non-toxicity, renewability, and ease of formation. However, alginate hydrogel beads are known to have a low stiffness, i.e., Young modulus <1 MPa, and a short dissolution time of between 1 h and 2 h in gastrointestinal fluid. This study aimed to fabricate calcium alginate hydrogel beads with desired properties like high stiffness and extended dissolution behaviour. A temperature-controlled extrusion–dripping method incorporating an immiscible interphase column was used to produce the ultra-high concentration (UHC) calcium hydrogel beads directly from unmodified alginate solution. The UHC beads have an extraordinary internal structure with thick calcium-alginate matrices and large pores in between the matrices. The Young’s modulus value of UHC calcium alginate beads was 3.6 MPa, which was approximately 8 times higher than the normal calcium alginate beads. The release profile for the model drug (i.e., methylene blue) encapsulated in UHC beads was found to be extended to 4 h at 80% of drug release (t80). The kinetics of drug release fitted well with the Korsmeyer–Peppas model (r2 ⩾ 0.99) and followed the non-Fickian mechanism. These findings show that the preparation of calcium alginate beads featuring high stiffness and extended dissolution profile can be achieved without any chemical modification or additives. The UHC calcium alginate bead holds excellent promise as an encapsulation carrier of drugs or food used in controlled delivery applications

Expression and purification of the matrix protein of Nipah virus in baculovirus insect cell system

Nipah virus (NiV) causes fatal respiratory illness and encephalitis in humans and animals. The matrix (M) protein of NiV plays an important role in the viral assembly and budding process. Thus, an access to the NiV M protein is vital to the design of viral antigens as diagnostic reagents. In this study, recombinant DNA technology was successfully adopted in the cloning and expression of NiV M protein. A recombinant expression cassette (baculovirus expression vector) was used to encode an N-terminally His-tagged NiV M protein in insect cells. A time-course study demonstrated that the highest yield of recombinant M protein (400–500 μg) was expressed from math formula infected cells 3 days after infection. A single-step purification method based on metal ion affinity chromatography was established to purify the NiV M protein, which successfully yielded a purity level of 95.67% and a purification factor of 3.39. The Western blotting and enzyme-linked immunosorbent assay (ELISA) showed that the purified recombinant M protein (48 kDa) was antigenic and reacted strongly with the serum of a NiV infected pig

Purification of the recombinant enhanced green fluorescent protein from Escherichia coli using alcohol + salt aqueous two-phase systems

The enhanced green fluorescent protein (EGFP) is widely used as a marker in life science. Currently, purifications of the EGFP mostly involve chromatographic methods, which are multistep, time-consuming and costly. In the present study, the recombinant EGFP expressed in Escherichia coli was purified using an economic aqueous two-phase system (ATPS). Short-chain aliphatic alcohol and organic salt were chosen as the phase-forming components owing to their recyclability and biodegradability, respectively. The partition behaviour of EGFP was evaluated under the varying conditions of ATPS, including types and concentrations of phase-forming components, feedstock concentration, and pH. In an optimal primary 2-g ATPS comprising 1-propanol and tripotassium citrate, a high recovery of EGFP (i.e., 92.1%) was attained in the salt-rich bottom phase. To facilitate the easy recovery of purified EGFP, a secondary ATPS was used to back extract the EGFP to a new top ethanol-rich top phase, and the ethanol was removed from the purified EGFP via evaporation. The 1-propanol and ethanol used in the primary and secondary ATPSs (i.e. 20-g system) were successfully recycled in three successive rounds of EGFP purification, yielding the average EGFP purification factor of 11.34 and 75.7% of EGFP yield. The purification of EGFP using the two stages of alcohol + salt ATPSs is efficient in terms of operation time, cost and process scalability

Size-selective purification of hepatitis B virus-like particle in flow-through chromatography: types of ion exchange adsorbent and grafted polymer architecture

Hepatitis B virus-like particles expressed in Escherichia coli were purified using anion exchange adsorbents grafted with polymer poly(oligo(ethylene glycol) methacrylate) in flow-through chromatography mode. The virus-like particles were selectively excluded, while the relatively smaller sized host cell proteins were absorbed. The exclusion of virus-like particles was governed by the accessibility of binding sites (the size of adsorbents and the charge of grafted dextran chains) as well as the architecture (branch-chain length) of the grafted polymer. The branch-chain length of grafted polymer was altered by changing the type of monomers used. The larger adsorbent (90 μm) had an approximately twofold increase in the flow-through recovery, as compared to the smaller adsorbent (30 μm). Generally, polymer-grafted adsorbents improved the exclusion of the virus-like particles. Overall, the middle branch-chain length polymer grafted on larger adsorbent showed optimal performance at 92% flow-through recovery with a purification factor of 1.53. A comparative study between the adsorbent with dextran grafts and the polymer-grafted adsorbent showed that a better exclusion of virus-like particles was achieved with the absorbent grafted with inert polymer. The grafted polymer was also shown to reduce strong interaction between binding sites and virus-like particles, which preserved the particles' structure

Primary recovery of lipase derived from Burkholderia sp. ST8 with aqueous micellar two-phase system.

The partitioning and recovery of lipase derived from Burkholderia sp. ST8 strain was explored using temperature-induced aqueous micellar two-phase system (AMTPS) composed of single nonionic surfactant. Nonionic surfactant Triton X-114 and Pluronic series (triblock copolymer) were evaluated in terms of their clouding phenomenon (cloud-point temperature) and the performance of the lipase partitioning in these AMTPSs. Pluronic L81 showed the most optimum partition efficiency for the recovery of lipase to the micellar phase of the AMTPS. Based on the AMTPS which consisted of 24% (w/w) Pluronic L81 and 0.5% (w/w) potassium chloride (KCl), the selectivity of lipase partitioned to bottom phase has been enhanced to 0.035 and the lipase was purified 7.2 fold. Furthermore, the lipase from the micellar phase was consecutively extracted to a new aqueous solution, with an aim of removing the surfactant from the purified lipase. It was attained by replacing the aqueous top phase from the primary recovery of AMTPS with a new potassium thiocyanate (KSCN) solution. The lipase was then recovered in the newly formed bottom aqueous phase which culminated in the yield of 89% and partition coefficients of 0.34 and 4.50 for lipase and surfactant, respectively. AMTPS offers a convenient and efficient method for the primary recovery of lipase with low cost, large loading capacity and the potential of linear scale up

Recovery of human interferon alpha-2b from recombinant Escherichia coli using alcohol/salt-based aqueous two-phase systems

The purification of intracellular human recombinant interferon-alpha2b (IFN-α2b) from Escherichia coli (E. coli) was studied using alcohol/salt aqueous two-phase system (ATPS). The influences of nine biphasic systems comprising alcohol-based top phase (ethanol, 1-propanol and 2-propanol) and salt-based bottom phase (ammonium sulfate, di-potassium hydrogen phosphate and monosodium citrate) on IFN-α2b purification were studied. The results showed that the optimum condition for purification of IFN-α2b was achieved in ATPS composed of 18% (w/w) 2-propanol with 22% (w/w) ammonium sulfate in the presence of 1% (w/w) sodium chloride (NaCl). The purified IFN-α2b recorded a purification factor (PF) of 16.24 with the yield of 74.64%

Liquid Biphasic Electric Partitioning System as a Novel Integration Process for Betacyanins Extraction From Red-Purple Pitaya and Antioxidant Properties Assessment

Nowadays, downstream bioprocessing industries inclines towards the development of a green and high efficient bioseparation technology. Betacyanins are presently gaining higher interest in the food science as driven by their high tinctorial strength and health promoting functional properties. In this study, a novel green integration process of liquid biphasic electric partitioning system (LBEPS) was proposed for betacyanins extraction from peel and flesh of red-purple pitaya. Initially, the betacyanins extraction using LBEPS with initial settings was compared with that of liquid biphasic partitioning system (LBPS), and the results revealed that both systems demonstrated a comparable betacyanins extraction. This was followed by further optimizing the LBEPS for better betacyanins extraction. Several operating parameters including operation time, voltage applied, and position of graphitic electrodes in the system were investigated. Moreover, comparison between optimized LBEPS and LBPS with optimized conditions of electric system (as post-treatment) as well as color characterization and antioxidant properties assessment were conducted. Overall, the betacyanins extraction employing the optimized LBEPS showed the significant highest values of betacyanins concentration in alcohol-rich top phase (Ct) and partition coefficient (K) of betacyanins from peel (99.256 ± 0.014% and 133.433 ± 2.566) and flesh (97.189 ± 0.172% and 34.665 ± 2.253) of red-purple pitaya. These results inferred that an optimal betacyanins extraction was successfully achieved by this approach. Also, the LBEPS with the peel and flesh showed phase volume ratio (Vr) values of 1.667 and 2.167, respectively, and this indicated that they have a clear biphasic separation. In addition, the peel and flesh extract obtained from the optimized LBEPS demonstrated different variations of red color as well as their antioxidant properties were well-retained. This article introduces a new, reliable, and effective bioseparation approach for the extraction of biomolecules, which is definitely worth to explore further as a bioseparation tool in the downstream bioprocessing

Biosensing of hepatitis B antigen with poly(acrylic acid) hydrogel immobilized with antigens and antibodies

Hydrogel based on poly(acrylic acid) (PAAc) polymers was successfully fabricated as the biosensor for detecting hepatitis B core antigen (HBcAg). Specifically, the pendant HBcAg and the anti-hepatitis B core antigen (anti-HBc) antibody were first immobilized on the PAAc, which were then covalently cross-linked via radical polymerization to form the HBcAg-sensitive (HBPAAc) hydrogel. The non-covalent affinity binding between the immobilized HBcAg and anti-HBc would be disrupted by the presence of free HBcAg in the HBPAAc hydrogel. The competitive binding of free HBcAg on the immobilized anti-HBc triggered the swelling of HBPAAc hydrogel. The equilibrium swelling ratio and the oscillatory swelling-deswelling kinetics of the HBPAAc hydrogel in response to protein concentration were studied. The swelling ratio of HBPAAc hydrogel increased along with an increase in HBcAg concentration until equilibrium was achieved at 4 mg/mL HBcAg. The HBPAAc hydrogel did not exhibit swelling/deswelling behavior when interacted with the negative control, i.e., bovine serum albumin (BSA). Based on the result of oscillatory swelling-deswelling of HBPAAc hydrogel, the minimum duration for HBcAg detection by the HBPAAc hydrogel was ∼20 min, whereas the regeneration of HBPAAc hydrogel took about 60 min. These results confirmed the reversibility and the reusability of this HBcAg-sensing HBPAAc hydrogel. Besides, the hydrogel demonstrated zero cross-reactivity to the hepatitis B surface antigen, a common serological marker for hepatitis B patients. The high sensitivity of HBPAAc hydrogel to the HBcAg was successfully demonstrated with quartz crystal microgravimetry. The magnitude of resonance frequency was inversely correlated with the swelling of HBPAAc hydrogel, which is governed by the concentration of analyte HBcAg. The application of HBPAAc hydrogel as a biosensor component in the detection and surveillance of hepatitis B holds great promises

Purification of rabbit polyclonal immunoglobulin G with ammonium sulphate precipitation and mixed-mode chromatography

Immunoglobulins G (IgG) against hepatitis B core antigen (HBcAg) was successfully purified using a purification scheme comprising ammonium sulphate precipitation and SepFast™ MM AH-1 column chromatography. Ammonium sulphate precipitation performed at 40% saturation was optimum in terms of the recovered polyclonal IgG concentration (7.8 mg/ml) and the removal of albumin (72%). The yield, purity and purification factor achieved from this simple purification method were 99%, 94% and 7.8, respectively. The IgG recovered from ammonium sulphate precipitation was subjected to SepFast™ MM AH-1 column chromatography and the purity of IgG was further increased to 98%, corresponding to a purification factor of 8.1. Protein aggregation was also reduced significantly in the purified IgG sample. Furthermore, the salt content in the purified sample was reduced by 75% and therefore the need of desalting final product was eliminated. Enzyme-linked immunosorbent assay (ELISA) showed that the antigenicity of anti-HBcAg IgG obtained after these purification processes was maintained