Single-step Operation Research Articles

The single-step operation for enzyme-modified cheese production: Influence and importance of process parameters

Enzyme-modified cheeses (EMCs) are natural flavour ingredients with intense cheese flavour. This study utilized a single-step process to produce an EMC; a single step process offers benefits such as shorter processing time, reduced equipment needs, and lower costs. However, product development and optimization are challenging due to multiple influencing factors. The study investigated incubation parameters (temperature, time, agitation speed), enzyme concentrations (proteolytic and lipolytic ratios), and homogenisation pressures to determine the important factors. The proteolytic ripening parameters, free fatty acid profiles, and volatile compounds of EMCs were examined. Key findings indicate that incubation conditions and protease concentration significantly influence EMC properties. Proteolytic enzyme concentration and incubation time were the main contributors to proteolytic ripening, while lipolytic ripening was primarily influenced by incubation temperature and agitation speed. Notably, incubation temperature was the most critical factor affecting the variation of volatile compounds in EMC production.

Flexible fabrication of core/shell nanoparticles for tailored infrared emissivity on aluminum via femtosecond laser self-deposition.

A metal surface with controllable infrared emissivity has a wide range of applications. However, a flexible and simple fabrication method is needed. Here, a controllable femtosecond laser self-deposition technology was developed to fabricate Al@AlOx core/shell micropillars (MPs) with diverse size distribution on the aluminum surface in a single-step operation under ambient conditions. By establishing a deterministic relationship between pulse-repetition frequency (PRF) and particle size distribution (PSD), we achieved continuous control of the infrared emissivity of the surface by lower PRF, ranging from low (0.31) to high (0.93). Additionally, by using higher PRF, we attained dual-band emissivity control, featuring high emissivity in the range of 10-14 µm and near-continuous change in the range of 2.5-10 µm.

Integration of a hamper pad on test strips for improved sensitivity of carbendazim detection

Lateral flow immunoassays (LFIAs) are widely used to determine carbendazim (CBZ) residues in food products due to their advantages of low cost, ease and rapid use, on-site detection capability. However, conventional LFIAs have low detection sensitivity. Although improvements have been made to increase the sensitivity, it is not sufficient. Here, a hamper pad, polyvinyl alcohol coated on a nitrocellulose membrane, was integrated to enhance the sensitivity of LFIA for CBZ detection. The hamper pad was inserted between the conjugated and nitrocellulose pads to delay the flow rate, thereby increasing the possibility of the antibody and target analyte binding. This platform exhibited a fourfold sensitivity increase in CBZ detection compared with the conventional LFIA, and its limit of detection was 1.6 ng/mL. In addition, a single-step operation was successfully applied to detect CBZ in rice (white rice, brown rice, sticky rice, and paddy) and soybean samples, with acceptable recoveries of 93.6%–120.0%. This novel device was compared to the standard high-performance liquid chromatography method, which shows high accuracy with a Kappa coefficient of 0.91. Therefore, improved sensitivity with a rapid, simple, and inexpensive device could facilitate the detection of CBZ residues in agricultural products for on-field screening and improved user-friendliness.

High-Throughput Microfluidic Extraction of Platelet-free Plasma for MicroRNA and Extracellular Vesicle Analysis.

Cell-free RNAs and extracellular vesicles (EVs) are valuable biomarkers in liquid biopsies, but they are prone to preanalytical variabilities such as nonstandardized centrifugation or ex vivo blood degradation. Herein, we report a high-throughput and label-free inertial microfluidic device (ExoArc) for isolation of platelet-free plasma from blood for RNA and EV analysis. Unlike conventional inertial microfluidic devices widely used for cell sorting, a submicrometer size cutoff (500 nm) was achieved which completely removed all leukocytes, RBCs, platelets, and cellular debris based on differential lateral migration induced by Dean vortices. The single-step operation also reduced platelet-associated miRNAs (∼2-fold) compared to centrifugation. We clinically validated ExoArc for plasma miRNA profiling (39 samples) and identified a 7-miRNA panel that detects non-small cell lung cancer with ∼90% sensitivity. ExoArc was also coupled with size exclusion chromatography (SEC) to isolate EVs within 50 min with ∼10-fold higher yield than ultracentrifugation. As a proof-of-concept for EV-based transcriptomics analysis, we performed miRNA analysis in healthy and type 2 diabetes mellitus (T2DM) subjects (n = 3 per group) by coupling ExoArc and ExoArc+SEC with quantitative polymerase chain reaction (RT-qPCR) assay. Among 293 miRNAs detected, plasmas and EVs showed distinct differentially expressed miRNAs in T2DM subjects. We further demonstrated automated in-line EV sorting from low volume culture media for continuous EV monitoring. Overall, the developed ExoArc offers a convenient centrifugation-free workflow to automate plasma and EV isolation for point-of-care diagnostics and quality control in EV manufacturing.

Free gingival grafting technique for gingival recession coverage: A 6-month follow-up interventional study

Background: Both the practitioner and the patient frequently deal with gingival recession. In Miller’s Classes I and II mandibular gingival recession, the goal of this study was to evaluate the predictability of the free gingival graft (FGG), as a single-step operation in terms of root coverage and esthetics. Materials and Methods: 10 patients between the ages of 25 and 50 who were sent to the Department of Periodontics (3 men and 7 women) made up the study group. There were a total of 14 mandibular recession sites that were chosen. Recession depth (RD), recession width, probing depth (PD), clinical attachment level (CAL), width of attached gingiva (WAG), and visual analog scale (VAS) were assessed at baseline, 3 months, and 6 months post-operatively. Results: The mean RD was 3.13±2.0 mm at the baseline and decreased to 0.80±0.78 mm after 6 months. At baseline, the VAS was 3.52±0.81, and at 6 months after surgery, it had improved to a mean of 6±2.14. From a baseline WAG of 0.35±0.38 to 2.83±0.68 mm, there wasa significant increase with p<0.0001. Six months after surgery, there was an increase in CAL, from 5.63±1.12 to 1.28±0.76 mm. In addition, PD improved from 1.98±0.54 to 0.97±0.36 mm. Conclusion: FGG showed statistically significant gain in recession coverage and had good esthetic score. The technique produced a reliable single-step gain in WAG as well as root coverage in cases of Miller’s Classes I and II gingival recession.

Fused chromeno-pyrano-pyrimidinediones: Multi-component green synthesis and electrochemical properties

An efficient solvent-free green multi-component reaction strategy for the synthesis of diversified fused chromeno-pyrano-pyrimidinediones (4) by the reaction of 4-hydroxy-1-benzopyran-2-one (1), benzaldehydes (2) and thiobarbituric acid (3) in the presence of thiamine hydrochloride at room temperature in a single step operation has been developed. Simple to perform, neat reaction conditions, water workup, short reaction times, high product yields, scalability, catalyst reusability, products free from column purification and excellent greenness of the process are the noteworthy features of this multi-component reaction approach. Hence, the established methodology meets the concept of “benign by design”. Further, electrochemical properties of the synthesized compounds (4) have been studied by cyclic voltammetry. The HOMO/LUMO values of titled compounds (4) are obtained in the ranges of −5.72 to −5.37 eV/−2.57 to −2.21 eV that are comparable with the reported hole transporting materials.

Highly chemoselective oxidative dimerization of indolosesquiterpene alkaloids: a biomimetic approach to dixiamycin.

Dimeric indolosesquiterpene alkaloids, typically N-N- and C-N-linked xiamycin dimers, feature a pentacyclic framework with four contiguous stereogenic centers at the periphery of a trans-decalin scaffold to which a carbazole unit is attached. In comparison with actual biosynthetic dixiamycin derivatives, we designed C-C-linked xiamycin dimers, aiming to use them as a powerful tool to create unique scaffolds as drug candidates. In this work, we disclose the first synthetic route to access a C-C dimeric indolosesquiterpene skeleton, featuring a hypervalent iodine (PIFA)-catalyzed oxidative dimerization reaction in a single-step operation with overwhelming control over the chemoselectivity and regioselectivity. This strategy has been successfully applied to the synthesis of a C-C dimer of xiamycin A (3) and xiamycin A methyl ester (15) that demonstrates a new synthetic pathway for dimeric indolosesquiterpene alkaloids.

Palladium-catalyzed cyclization/carbonylation of iodoarene-tethered propargyl ethers with nitroarenes for the synthesis of acetamides-functionalized benzofurans

A general and efficient protocol based on palladium-catalyzed intramolecular cyclization and reductive aminocarbonylation reaction for the synthesis of acetamide-functionalized benzofurans has been explored. The reaction using iodoarene-tethered propargyl ethers and nitroarenes as the starting materials. This reaction features the formation of structure defined benzofurans with acetamides as attractive functional groups in a single step operation. By using Mo(CO)6 as both CO source and reductant, a variety of acetamides-functionalized benzofurans were obtained in moderate to good yields with good functional group compatibility.

Efficient scheme for implementing a hybrid Toffoli gate with two NV ensembles simultaneously controlling a single superconducting qubit

The Toffoli gate is a three-qubit controlled-controlled-NOT gate, which plays a central role in quantum information processing and quantum computing. Recently, hybrid systems and hybrid quantum gates have attracted much attention. We propose an efficient scheme to implement a hybrid Toffoli gate with two nitrogen-vacancy center ensembles (NV ensembles) as the control qubits and a single superconducting flux qubit as the target qubit. This hybrid Toffoli gate is realized by employing two NV ensembles coupled to a superconducting qutrit. The hybrid Toffoli gate is constructed by a controlled-controlled-phase (CCPHASE) gate sandwiched between two Hadamard gates applied on the target qubit. Since the CCPHASE gate is realized using only a single-step operation and no conventional gate decomposition protocol is applied, the Toffoli-gate implementation is greatly simplified. Because the higher energy level of the flux qutrit is not populated, the decoherence of this level is greatly suppressed. In addition, our hybrid Toffoli gate can be used to generate a hybrid Greenberger–Horne–Zeilinger entangled state of a flux qubit and two NV ensembles. Numerical simulations demonstrate that high-fidelity implementation of a hybrid Toffoli gate is feasible within current experimental technology. This proposal is universal and can be applied to accomplish the same task in a wide range of physical systems.

A high strength Al-Zr alloy with good electrical conductivity by combining gas-assisted continuous casting and extrusion with subsequent thermomechanical treatment

A high strength Al-Zr alloy was prepared based on a novel technique called gas-assisted continuous casting and extrusion (GAC). Results show that the solid solubility of Zr in the Al matrix could be increased due to the non-equilibrium solidification during the GAC process. After aging treatment (350 °C/275 h), the alloy has excellent combined properties (tensile strength and electrical conductivity of 200 MPa and 59.6% IACS, respectively); after cold drawing (94% deformation), the alloy can have tensile strength up to 278 MPa and good electrical conductivity (55.2% IACS). The GAC technology can fabricate aluminum alloy rod with higher solid solubility of Zr in a single-step operation, which is expected to be applied to the efficient preparation of high performance Al-Zr alloy wires.

One-step implementation of a multi-target-qubit controlled-phase gate with photonic qubits encoded via eigenstates of the photon-number parity operator

In recent years, quantum state engineering and quantum information processing using microwave fields and photons have received increasing attention. In addition, multiqubit gates play an important role in quantum information processing. In this work, we propose to encode a photonic qubit via two arbitrary orthogonal eigenstates (with eigenvalues $\ifmmode\pm\else\textpm\fi{}1$, respectively) of the photon-number parity operator. With such encoding, we then present a single-step method to realize a multi-target-qubit controlled-phase gate with one photonic qubit simultaneously controlling $n\ensuremath{-}1$ target photonic qubits, by employing $n$ microwave cavities coupled to one superconducting flux qutrit. This proposal can be applied not only to implement nonhybrid multi-target-qubit controlled-phase gates using photonic qubits with various encodings, but also to realize hybrid multi-target-qubit controlled-phase gates using photonic qubits with different encodings. The gate realization requires only a single-step operation. The gate operation time does not increase with the number of target qubits. Because the qutrit remains in the ground state during the entire operation, decoherence from the qutrit is greatly suppressed. As an application, we show how to apply this gate to generate a multicavity Greenberger-Horne-Zeilinger (GHZ) entangled state with general expression. Depending on the specific encodings, we further discuss the preparation of several nonhybrid and hybrid GHZ entangled states of multiple cavities. We numerically investigate the circuit-QED experimental feasibility of creating a three-cavity spin-coherent hybrid GHZ state. This proposal can be extended to accomplish the same tasks in a wide range of physical systems, such as multiple microwave or optical cavities coupled to a three-level natural or artificial atom.

Production and Recovery of Ectoine: A Review of Current State and Future Prospects

Ectoine (1,4,5,6-tetrahydro-2-methyl-4-pyrimidinecarboxylic acid) is a revolutionizing substance with vast applications in the cosmetic and food industries. Ectoine is often sourced from halobacteria. The increasing market demand for ectoine has urged the development of cost-effective and sustainable large-scale production of ectoine from microbial sources. This review describes the existing and potential microbial sources of ectoine and its derivatives, as well as microbial production and fermentation approaches for ectoine recovery. In addition, conventional methods and emerging technologies for enhanced production and recovery of ectoine from microbial fermentation with a focus on the aqueous biphasic system (ABS) are discussed. The ABS is a practically feasible approach for the integration of fermentation, cell disruption, bioconversion, and clarification of various biomolecules in a single-step operation. Nonetheless, the implementation of the ABS on an industrial-scale basis for the enhanced production and recovery of ectoine is yet to be exploited. Therefore, the feasibility of the ABS to integrate the production and direct recovery of ectoine from microbial sources is also highlighted in this review.

Asymmetric alkene-alkene reductive cross-coupling reaction via visible-light photoredox/cobalt dual catalysis.

The first example of asymmetric alkene-alkene reductive coupling is demonstrated via visible-light-fueled photoredox/cobalt dual catalysis. The desymmetrization reaction provided products (>20 examples) with up to five chiral centers in single-step operation in up to 95% yields with very high relative (>99 : 1 dr) and absolute stereochemistry (up to 98 : 2 er) control. The preliminary mechanistic investigations suggested that the critical mechanistic steps involved light-mediated controlled low-valent cobalt complex generation, oxidative ene-ene cyclization, and protonation.

Boronate Affinity-Amplified Electrochemical Aptasensing of Lipopolysaccharide.

As lipopolysaccharide (LPS) is closely associated with sepsis and other life-threatening conditions, the point-of-care (POC) detection of LPS is of significant importance to human health. In this work, we illustrate an electrochemical aptasensor for the POC detection of low-abundance LPS by utilizing boronate affinity (BA) as a simple, efficient, and cost-effective amplification strategy. Briefly, the BA-amplified electrochemical aptasensing of LPS involves the tethering of the aptamer receptors and the BA-mediated direct decoration of LPS with redox signal tags. As the polysaccharide chain of LPS contains hundreds of cis-diol sites, the covalent crosslinking between the phenylboronic acid group and cis-diol sites can be harnessed for the site-specific decoration of each LPS with hundreds of redox signal tags, thereby enabling amplified detection. As it involves only a single-step operation (∼15 min), the BA-mediated signal amplification holds the significant advantages of unrivaled simplicity, rapidness, and cost-effectiveness over the conventional nanomaterial- and enzyme-based strategies. The BA-amplified electrochemical aptasensor has been successfully applied to specifically detect LPS within 45 min, with a detection limit of 0.34 pg/mL. Moreover, the clinical utility has been validated based on LPS detection in complex serum samples. As a proof of concept, a portable device has been developed to showcase the potential applicability of the BA-amplified electrochemical LPS aptasensor in the POC testing. In view of its simplicity, rapidness, and cost-effectiveness, the BA-amplified electrochemical LPS aptasensor holds broad application prospects in the POC testing.

Single-step implementation of a hybrid controlled-not gate with one superconducting qubit simultaneously controlling multiple target cat-state qubits

Hybrid quantum gates have recently drawn considerable attention. They play significant roles in connecting quantum information processors with qubits of different encoding and have important applications in the transmission of quantum states between a quantum processor and a quantum memory. In this work, we propose a single-step implementation of a multi-target-qubit controlled-NOT gate with one superconducting (SC) qubit simultaneously controlling $n$ target cat-state qubits. In this proposal, the gate is implemented with $n$ microwave cavities coupled to a three-level SC qutrit. The two logic states of the control SC qubit are represented by the two lowest levels of the qutrit, while the two logic states of each target cat-state qubit are represented by two quasi-orthogonal cat states of a microwave cavity. This proposal operates essentially through the dispersive coupling of each cavity with the qutrit. The gate realization is quite simple because it requires only a single-step operation. There is no need of applying a classical pulse or performing a measurement. The gate operation time is independent of the number of target qubits, thus it does not increase as the number of target qubits increases. Moreover, because the third higher energy level of the qutrit is not occupied during the gate operation, decoherence from the qutrit is greatly suppressed. As an application of this hybrid multi-target-qubit gate, we further discuss the generation of a hybrid Greenberger-Horne-Zeilinger (GHZ) entangled state of SC qubits and cat-state qubits. As an example, we numerically analyze the experimental feasibility of generating a hybrid GHZ state of one SC qubit and three cat-state qubits within present circuit QED technology.

Mono-PEGylated lysozyme purification with increased productivity and isomer differentiation through heparin monolith chromatography

PEGylated protein purification with the required quality attributes has represented a bioengineering challenge and Affinity Monolith Chromatography (AMC) has never been exploited for this goal. This work reports the generation of a heparin-modified affinity monolith disk by reductive alkylation with raised ligand density for its use as chromatographic support in the separation of lysozyme PEGylation reactions (LPRs) with three different PEG sizes (1, 20 and 40 kDa). For immobilized heparin determination a modified toluidine colorimetric assay adapted to microplate format was proposed. The heparin modified-disk was able to differentiate positional isomers of 20 kDa mono-PEGylated lysozyme at neutral pH using a salt linear gradient. Identity of PEG-conjugates was verified by SDS-PAGE and positional isomers were partially characterized by peptide mapping mass spectrometry. 20 kDa mono-PEGylated lysozyme conjugate purity (99.69 ± 0.05%) was comparable with traditional chromatographic methods while productivity (0.0964 ± 0.0001 mg/mL*min) was increased up to 6.1 times compared to that obtained in heparin packed-bed affinity chromatography procedures. The proposed AMC method represents a reliable, efficient, easy-handling, fast and single-step operation for the analysis or preparative isolation of PEGylated proteins containing a heparin binding domain.

Automatic generation of 3d spiral tool path for incremental sheet metal forming of mechanical parts with complex geometry

Incremental sheet metal forming is a flexible manufacturing technology that allows to form of various components on the same milling machine, without expensive tools. A hemispherical tool moves along a CNC-controlled tool path and deforms the sheet into the desired shape. The tool path has a significant role in the geometric accuracy of the final part. There has been very little research on the problem of the forming of sophisticated parts with asymmetric wall angles. This paper presents a new approach to generating optimized tool paths for single-point incremental sheet forming (SPIF). At first, a strategy is proposed for the automatic generation of a 3D tool path during forming in a single-step operation. Then, a systematic technique of creating intermediate shapes is investigated by defining tool paths interpolated from the final part shape. The proposed methodology is applied to form a hip cup prosthesis. This part has a complex asymmetric geometry with important angles, a multi-step approach is used. The proposed methodology to define the different tool paths was implemented in Matlab. A numerical simulation of the incremental forming process is performed to predict the final geometry of the aluminum sheet. A comparison of desired and predicted geometries shows the reliability of the proposed method.

Extractive fermentation of Kytococcus sedentarius TWHKC01 using the aqueous biphasic system for direct recovery of keratinase

BackgroundExtractive fermentation using aqueous biphasic system (ABS) can integrate the cultivation of microbial cells and direct recovery of the target enzyme into a one-step operation which simplifies the overall time and costs for the recovery processes. MethodsABS extractive fermentation was applied in this study for the fermentation and instant recovery of Kytococcus sedentarius TWHKC01 keratinase. The polyethylene glycol (PEG) 2000 and sodium citrate were used as the ABS phase components for the cells growth and keratinase production. FindingsA total of 182.44 U/mL of keratinase was recovered in the top phase of the ABS composed of 25% (w/w) PEG 2000 and 10% (w/w) tri-sodium citrate which was higher than the fermentation without integrated with ABS (161.33 U/mL). Repetitive batch fermentation was performed with the ABS by retaining the K. sedentarius TWHKC01 cells in the bottom phase of the ABS and continuously recovering the keratinase from top phase. The relative keratinase activity decreases from 1.12 to 0.60 after four batches of the ABS extractive fermentation. ABS extractive fermentation is a promising approach to integrate the fermentation and recovery of keratinase enzyme with a single-step operation.

Impact of Gastropexy/Omentopexy on Gastrointestinal Symptoms after Laparoscopic Sleeve Gastrectomy

BackgroundLaparoscopic sleeve gastrectomy (LSG) has become a single-step operation for the management of severe obesity. A statistically significant number of participants who undergo this procedure experience nausea, vomiting, and reflux symptoms early after the operation. The objectives of this study were to measure the positive or negative effect of gastropexy on reducing distressing postoperative LSG-related gastrointestinal symptoms.Patients and MethodsThis was a comparative randomized study conducted from January 2018 to January 2021. The study was carried out in the general surgery department at Menoufia University Hospital, Menoufia Faculty of Medicine in Egypt. Two hundred participants were included randomly during this trial. The participants were divided into two groups, with 100 patients in each group. Patients in group A underwent gastropexy, and patients in group B underwent LSG without gastropexy.ResultsThere was no significant difference between the groups in age or sex (p > 0.05). There was no significant difference in the length of hospital stay (p > 0.05). There was a significant difference between the two groups regarding nausea, vomiting, reflux symptoms, and the amount and frequency of antiemetics used (p < 0.001). There was also a significant difference in hospital readmissions (p < 0.05) and in clinic visits during the postoperative period.ConclusionsPatients who underwent gastropexy showed a significant reduction in antiemetic consumption and a significantly lower incidence of postoperative nausea, vomiting, gastroesophageal reflux disease symptoms and gastric torsion than those who did not undergo gastropexy.Graphical abstract

Total Synthesis of (-)-Calycanthine via Iron-Catalyzed Stereoselective Oxidative Dimerization.

Dimeric cyclotryptamine alkaloids typically feature vicinal all-carbon quaternary stereocenters and four nitrogen atoms. In comparison with the actual biosynthetic tryptophan derivatives, we designed the 2N-featured monomer 7, aiming to construct vicinal all-carbon quaternary stereocenters via a one-step dimerization process to access the 4N-featured isomeric members of this family. In this work, we disclose the first synthetic route to access the skeleton of (-)-isocalycanthine, featuring an iron-catalyzed oxidative dimerization reaction in a catalytic single-step operation with an overwhelming control of the absolute and relative stereochemistry. This strategy has been successfully applied to the total synthesis of (-)-calycanthine and 16 isocalycanthine derivatives, which demonstrates a new synthetic pathway for dimeric cyclotryptamine alkaloids.