Biomimetic and Multifunctional Hemostatic Hydrogel with Rapid Thermoresponsive Gelation and Robust Wet Adhesion for Emergency Hemostasis: A Rational Design Based on Photo-Cross-Linking Coordinated Hydrophilic-Hydrophobic Balance Strategies.

Uncontrolled bleeding in emergency situations is a great threat to both military and civilian lives, and an ideal hemostat for effectively controlling prehospital hemorrhage is urgently needed but still lacking. Although hemostatic hydrogels are promising for emergency hemostasis, they are currently challenged by either the mutual exclusion between a short gelation time and strong adhesive network or the insufficient functionality of ingredients and complicated operations for in situ curing. Herein, an extracellular matrix biopolymer-based and multifunctional hemostatic hydrogel that simultaneously integrates rapid thermoresponsive gelation, robust wet adhesion, and ease of use in emergencies is rationally engineered. This hydrogel can be conveniently used via simple injection and achieves instant sol-gel phase transition at body temperature. Its comprehensive performance could be facilely regulated by tuning the proportions of components, and the optimal performance (gelation time 6-8 s, adhesion strength 125 ± 3.6 kPa, burst pressure 282 ± 4.1 mmHg) is established due to the coordinated enhancement of the photo-cross-linking pretreatment and the hydrophilic-hydrophobic balance among various interactions in the hydrogel system. Additionally, it exhibits significant coagulation effect in vitro and enables effective hemostasis and wound healing in vivo. This work provides a promising platform for versatile applications of hydrogel-based materials, including emergency hemostasis.

Effects of Chitosan and Cellulose Derivatives on Sodium Carboxymethyl Cellulose-Based Films: A Study of Rheological Properties of Film-Forming Solutions.

Bio-based packaging materials and efficient drug delivery systems have garnered attention in recent years. Among the soluble cellulose derivatives, carboxymethyl cellulose (CMC) stands out as a promising candidate due to its biocompatibility, biodegradability, and wide resources. However, CMC-based films have limited mechanical properties, which hinders their widespread application. This paper aims to address this issue by exploring the molecular interactions between CMC and various additives with different molecular structures, using the rheological method. The additives include O-carboxymethylated chitosan (O-CMCh), N-2-hydroxypropyl-3-trimethylammonium-O-carboxymethyl chitosan (HTCMCh), hydroxypropyltrimethyl ammonium chloride chitosan (HACC), cellulose nanocrystals (CNC), and cellulose nanofibers (CNF). By investigating the rheological properties of film-forming solutions, we aimed to elucidate the influencing mechanisms of the additives on CMC-based films at the molecular level. Various factors affecting rheological properties, such as molecular structure, additive concentration, and temperature, were examined. The results revealed that the interactions between CMC and the additives were dependent on the charge of the additives. Electrostatic interactions were observed for HACC and HTCMCh, while O-CMCh, CNC, and CNF primarily interacted through hydrogen bonds. Based on these rheological properties, several systems were selected to prepare the films, which exhibited excellent transparency, wettability, mechanical properties, biodegradability, and absence of cytotoxicity. The desirable characteristics of these selected films demonstrated the strong biocompatibility between CMC and chitosan and cellulose derivatives. This study offers insights into the preparation of CMC-based food packaging materials with specific properties.

One-Pot Synthesis of Cellulose/MXene/PVA Foam for Efficient Methylene Blue Removal.

Ti3C2Tx MXene has attracted considerable interest as a new emerging two-dimensional material for environmental remediation due to its high adsorption capacity. However, its use is greatly limited by its poor mechanical properties, low processability and recyclability, and the low dispersity of such powder materials. In this work, a porous adsorbent (C-CMP) containing cellulose nanocrystals (CNC), Ti3C2Tx MXene and polyvinyl alcohol (PVA) was prepared by a simple and environmentally-friendly foaming method. Glutaraldehyde was used as crosslinker to improve the mechanical properties and boost the adsorption efficiency of methylene blue (MB) molecules. Fourier transform infrared (FT-IR), elemental analysis (EDX) and thermogravimetric analysis (TGA) further confirmed that the preparation of the C-CMP foam and cross-linking reaction were successful. Scanning electron microscope (SEM) indicated that the macropores were distributed homogeneously. The adsorption experiment showed that maximum adsorption capacity of MB can reach 239.92 mg·g-1 which was much higher than anionic dye (methyl orange, 45.25 mg·g-1). The adsorption behavior fitted well with the Langmuir isotherm and pseudo-second-order kinetic models. Thermodynamic analysis indicated that the adsorption process was spontaneous and endothermic. Based on FT-IR, EDX and X-ray photoelectron spectroscopy (XPS) analysis, the adsorption mechanism between C-CMP and MB molecules was attributed to electrostatic interaction.

Curing Kinetics Modeling of Epoxy Modified by Fully Vulcanized Elastomer Nanoparticles Using Rheometry Method.

In this study, the curing kinetics of epoxy nanocomposites containing ultra-fine full-vulcanized acrylonitrile butadiene rubber nanoparticles (UFNBRP) at different concentrations of 0, 0.5, 1 and 1.5 wt.% was investigated. In addition, the effect of curing temperatures was studied based on the rheological method under isothermal conditions. The epoxy resin/UFNBRP nanocomposites were characterized via Fourier transform infrared spectroscopy (FTIR). FTIR analysis exhibited the successful preparation of epoxy resin/UFNBRP, due to the existence of the UFNBRP characteristic peaks in the final product spectrum. The morphological structure of the epoxy resin/UFNBRP nanocomposites was investigated by both field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) studies. The FESEM and TEM studies showed UFNBRP had a spherical structure and was well dispersed in epoxy resin. The chemorheological analysis showed that due to the interactions between UFNBRP and epoxy resin, by increasing UFNBRP concentration at a constant temperature (65, 70 and 75 °C), the curing rate decreases at the gel point. Furthermore, both the curing kinetics modeling and chemorheological analysis demonstrated that the incorporation of 0.5% UFNBRP in epoxy resin matrix reduces the activation energy. The curing kinetic of epoxy resin/UFNBRP nanocomposite was best fitted with the Sestak-Berggren autocatalytic model.

Ag22 Nanoclusters with Thermally Activated Delayed Fluorescence Protected by Ag/Cyanurate/Phosphine Metallamacrocyclic Monolayers through In-Situ Ligand Transesterification.

The composition of protection monolayer exerts great influence on the molecular and electronic structures of atomically precise monolayer protected metal nanoclusters. Four isostructural Ag/cyanurate/phosphine metallamacrocyclic monolayer protected Ag22 nanoclusters are synthesized by kinetically controlled in-situ ligand formation-driven strategy. These eight-electron superatomic silver nanoclusters feature an unprecedented interfacial bonding structure with diverse E-Ag (E=O/N/P/Ag) interactions between the Ag13 core and metallamacrocyclic monolayer, and displays thermally activated delayed fluorescence (TADF), benefiting from their distinct donor-acceptor type electronic structures. This work not only unmasks a new core-shell interface involving cyanurate ligand but also underlines the significance of high-electron-affinity N-heterocyclic ligand in synthesizing TADF metal nanoclusters. This is the first mixed valence Ag0/I nanocluster with TADF characteristic.

Self-Luminescent Lanthanide Metal-Organic Frameworks as Signal Probes in Electrochemiluminescence Immunoassay.

The successful use of electrochemiluminescence (ECL) in immunoassay for clinical diagnosis requires development of novel ECL signal probes. Herein, we report lanthanide (Ln) metal-organic frameworks (LMOFs) as ECL signal emitters in the ECL immunoassay. The LMOFs were prepared from precursors containing Eu (III) ions and 5-boronoisophthalic acid (5-bop), which could be utilized to adjust optical properties. Investigations of ECL emission mechanisms revealed that 5-bop was excited with ultraviolet photons to generate a triplet-state, which then triggered Eu (III) ions for red emission. The electron-deficient boric acid decreased the energy-transfer efficiency from the triplet-state of 5-bop to Eu (III) ions; consequently, both were excited with high-efficiency at single excitation. In addition, by progressively tailoring the atomic ratios of Ni/Fe, NiFe composites (Ni/Fe 1:1) were synthesized with more available active sites, enhanced stability, and excellent conductivity. As a result, the self-luminescent europium LMOFs displayed excellent performance characteristics in an ECL immunoassay with a minimum detectable limit of 0.126 pg mL-1, using Cytokeratins21-1 (cyfra21-1) as the target detection model. The probability of false positive/false negative was reduced dramatically by using LMOFs as signal probes. This proposed strategy provides more possibilities for the application of lanthanide metals in analytical chemistry, especially in the detection of other disease markers.

Reaction Kinetics at PDMS-E Emulsion Droplet-Gelatin Interface.

In this work, interfacial reaction kinetics between α-[3-(2,3-epoxypropoxy)propyl]-ω-butyl-polydimethylsiloxane emulsion droplets with different sizes and gelatin was studied. The results of amino conversion rate determination show that the reaction proceeded in two steps. Fluorescence spectra analysis indicates that step 1 (0-2 h) should be the adsorption of gelatin on droplet surface. In step 2 (2-13 h), amino conversion rate increased rapidly. The reaction rate in step 2 ( k2) was obtained by using the 2nd-order approach to model the grafting reaction kinetics. The quantitative relationships among amino conversion rate, droplet size, the concentration of surfactant, reaction temperature, and time were described by linear regression models in given ranges of conditions in step 2. Thermodynamic analysis indicates that the interfacial reaction is an endothermic reaction. After 13 h, the reaction was almost stopped.

Induced Aggregation of Epoxy Polysiloxane Grafted Gelatin by Organic Solvent and Green Application.

In this paper, we studied the aggregation of amphiphilic polymer epoxy-terminated polydimethylsiloxane (PDMS-E) grafted gelatin (PGG) in water induced by methanol, ethanol, 2-propanol, acetone, tetrahydrofuran (THF), and 1,4-dioxane. The aggregation pattern of the polymer was monitored by infrared spectroscopy, X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. It was revealed that the aggregate morphology showed clear dependence on the solvent polarity. The PGG aggregates had regular spherical morphology in polar solvents, including water, methanol, ethanol, 2-propanol, and acetone. The coating performance was evaluated by X-ray photoelectron spectroscopy and friction experiment, and PGG and acetone coating exhibited excellent coating performance on the surface of pigskin. Gel was formed in acetone and tetrahydrofuran (THF) with the slow evaporation of solvent, and this property can possibly be applied to industrial sewage treatment. White precipitate and soft film were formed in non-polar 1,4-dioxane.

Scale Effect on the Interface Reaction between PDMS-E Emulsion Droplets and Gelatin.

In this study, the scale effect on the interface reaction between PDMS-E emulsion droplets and gelatin was studied systematically. The monodisperse α-[3-(2,3-epoxy-propoxy)propyl]-ω-butyl-polydimethylsiloxane (PDMS-E) emulsion droplets on different scales were prepared using a Shirasu porous glass (SPG) membrane with a 0.5 µm pore size. The zeta potential results showed that the surface charge density of PDMS-E droplets decreased with the droplet scale, and the variation went through three stages, which corresponded to the diameter ranges of 100-450, 450-680, and 670-800 nm, respectively. The results of Raman spectra indicated that the distribution concentration of head groups in surfactants decreased but the polar epoxy groups tend to be exposed on the interface with the increase in the droplet scale. This was conducive to the nucleophilic attack of amino groups in gelatin on the epoxy group. Thus, the conversion of amino groups was related to the scale of the PDMS-E droplet. This study might provide a proper way to control the rate of interfacial reaction between immiscible macromolecule monomers.

Highly Selective and Sensitive Colorimetric and Fluorescent Chemosensor for Rapid Detection of Ag+, Cu2+ and Hg2+ Based on a Simple Schiff Base.

A new reversible colorimetric and fluorescent chemosensor MMIP based on a simple Schiff base has been successfully synthesized. MMIP exhibited high selectivity and sensitivity towards Ag+, Cu2+ and Hg2+ ions with a short response time in DMSO/H2O (1/1, v/v) solution among various metal ions, and the results could be monitored directly by naked eyes. The binding stoichiometry between MMIP and Ag+/Hg2+/Cu2+ has been determined to be 1:2 by Job's plot and FT-IR analysis. MMIP could effectively detect Ag+, Cu2+ and Hg2+ over a wide pH range of 3-10. The good linear correlations were obtained in the concentration ranges of 0-20 µM for Ag+, Cu2+ and Hg2+. Thus sensor MMIP could be potentially used for the quantification of Ag+, Cu2+ and Hg2+ in aqueous solution.

A Phenylamine-Oligothiophene-Based Fluorescent Chemosensor for Selective Detection of Hg(II).

A phenylamine-oligothiophene-based fluorescent chemosensor I3TEA was reported. This sensor exhibited highly selective and fast detection of Hg(2+) ion in MeCN/H2O (8/2, v/v) solution through fluorescence quenching. The detection was unaffected by the other competitive metal cations. The low detection limit was found to be 5.92 × 10(-7) M. In addition, the recognition process is reversible and confirmed by EDTA experiment.

A Fast-Responsive Fluorescent Sensor for Hg(2+) with High Selectivity and Sensitivity in Aqueous Media.

A fast-responsive fluorescent phenylamine-oligothiophene sensor 2TBDA was reported. This sensor exhibited highly selective and sensitive detection of Hg(2+) ion in THF/H2O (7/3, v/v) solution through fluorescence quenching. The detection was not affected by the coexistence of other competitive metal ions. In addition, the detection limit was found to be as low as 3.841 × 10(-7) M.

New views on the reaction of primary amine and aldehyde from DFT study.

A general theoretical investigation on the reaction of primary amine with aldehyde was carried out by density functional theory. The calculation systems involve three kinds of primary amines (methylamine, vinylamine, and phenylamine) and three kinds of aldehydes (formaldehyde, acetaldehyde, and acrylaldehyde). The steric and electronic inductive effects on the reaction mechanism were studied. Results reveal that the nucleophilic attack of primary amine on aldehyde under neutral conditions leads to carbinolamines, rather than Schiff bases. The nucleophilic attack on the protonated aldehyde produces the protonated Schiff base. The steric hindrance of the aldehyde slows down the nucleophilic attack but allows enough time to abstract a H; consequently, the formation of the protonated Schiff base is preferred. During the carbinolamine protonation, the H(+) preferably locates on the amine nitrogen and then is abstracted by the hydroxyl oxygen over an energy barrier, leaving protonated Schiff base after timely water liberation. The formation of a prereaction potential energy well obviously softens the steric and electronic inductive effects on the active barrier for different reactants.

Fabrication and photoactivity of a tunable-void SiO2-TiO2 core-shell structure on modified SiO2 nanospheres by grafting an amphiphilic diblock copolymer using ARGET ATRP.

SiO2-based composites have important applications in various technological fields. In this work, a tunablevoid SiO2-TiO2 core-shell structure was successfully prepared for the first time using SiO2-polymethyl methacrylate (PMMA)-polyoligo(ethylene glycol)methyl ether methacrylate (PO(EO)nMA) (n = 2, 5, and 8). An amphiphilic copolymer was used as the template, and calcination was performed using tetrabutyl titanate (TBT) as the titanium source. SiO2-PMMA-b-PO(EO)nMA microspheres were first synthesized through activators regenerated by electron transfer-atom transfer radical polymerization. Methyl methacrylate and O(EO)nMA were grafted with different EO unit numbers onto the surface of the halogen functional group of SiO2. TBT was hydrolyzed along with the PO(EO)nMA chain through hydrogen bonding, and then the SiO2-TiO2 core-shell structure was acquired through calcination to remove the polymer. Simultaneously, amorphous TiO2 crystallized during calcination. A series of characterizations indicated that the amphiphilic block copolymer was grafted onto SiO2 mesoparticle surfaces, the titania samples existed only in the anatase phase, and the prepared SiO2-TiO2 had hierarchically nanoporous structures. The gradient hydrophilicity of the PMMA-b-PO(EO)nMA copolymer template facilitated the hydrolysis of TBT molecules along the PO(EO)nMA to PMMA segments, thereby tuning the space between the core and the shell. In addition, the space was about 6 nm when the EO number was 2, and the space was about 10 nm when the EO numbers were 5 and 8. The photocatalytic activities of the SiO2-TiO2 materials were tested on the photodegradation of methyl orange.

Data on searching for synergy between alcohol and salt to produce more potent and environmentally benign gas hydrate inhibitors.

In order to systematically study the synergistic effect of gas hydrate inhibition with mixtures of methanol (MeOH) and magnesium chloride (MgCl2), the impact of these compounds on the thermodynamic stability of methane hydrate in the systems of CH4-MeOH-H2O, CH4-MgCl2-H2O, and CH4-MeOH-MgCl2-H2O was experimentally investigated. The pressure and temperature conditions of the three-phase vapor-aqueous solution-gas hydrate equilibrium were determined for these systems. The resulting dataset has 164 equilibrium points within the range of 234-289 K and 3-13 MPa. All equilibrium points were measured as the endpoint of methane hydrate dissociation during the heating stage. The phase boundaries of methane hydrate were identified for 8 systems with MeOH (up to 60 mass%), 5 MgCl2 solutions (up to 26.7 mass%), and 14 mixtures of both inhibitors. Most equilibrium points were measured using a ramp heating technique (0.1 K/h) under isochoric conditions when the fluids were stirred at 600 rpm. It was found that even a 0.5 K/h heating rate for the CH4-MgCl2-H2O system at low salt concentrations, along with all mixed aqueous solutions with methanol, gives results that do not differ from 0.1 K/h, considering the measurement uncertainties. Most measurements for the CH4-MgCl2-H2O system at high salt content were acquired using a step heating technique. The coefficients of the empirical equations approximating the equilibrium points for each inhibitor concentration were defined. The change in the slope parameter of the empirical equation was analyzed as a function of inhibitor content. Correlations that accurately describe the thermodynamic inhibition effect of methane hydrate with methanol and magnesium chloride on a mass% and mol% scale were obtained. The freezing temperatures of single and mixed aqueous solutions of methanol and magnesium chloride were determined experimentally to confirm the thermodynamic consistency of the methane hydrate equilibrium data.

Approaching High-Performance TS-1 Zeolites in the Presence of Alkali Metal Ions via Combination of Adjusting pH Value and Modulating Crystal Size.

Lewis acid zeolites play an important role in industrially important green reactions closely related to fine chemical and biomass conversion. Titanium-doped TS-1 zeolite is a milestone Lewis acid zeolite widely used in industrially significant green oxidation processes with hydrogen peroxide as an oxidant under mild conditions. TS-1 zeolites are normally synthesized in basic conditions under hydrothermal treatment. Up to now, there has still been no success in synthesizing active TS-1 Lewis acid zeolites by using inorganic alkali, e.g., NaOH or KOH as base, which is cheaper and more stable compared to the quaternary ammonium hydroxide or organic amines used in traditional synthesis. Here, an inorganic base of NaOH was employed in synthesizing active TS-1 zeolites for the first time. The crucial factor was the control of adverse effects of sodium cations on the incorporation of active titanium cations. Higher catalytic activity was achieved by further reducing the size of the TS-1 crystal by using the seed-added strategy, which uses the catalytic activity of a commercial catalyst, the production cost being much lower than commercial TS-1 catalysts, indicating great commercial potential and the possibility of preparing other cheap Lewis acid catalysts by using inorganic alkali.

Highly sensitive fluorescent sensor for hypochlorite in nearly 100% aqueous solution and its application for live-cell, plant and zebrafish imaging.

A new ICT type D-π-A structured chemosensor DTB derived from a bithiophene-benzothiazole derivative has been synthesized. Sensor DTB showed a colorimetric and fluorometric dual-signaling response to hypochlorite (ClO-) in EtOH/HEPES solution (1/99, V/V, pH = 7.4, nearly 100% aqueous solution). Sensor DTB exhibited well specificity, high sensitivity and rapidity (<1 min) for ClO- with a detection limit of 25 nM. Sensor DTB features remarkable color changes and significant fluorescence "turn-on" response (ca. 45 fold) after treating with ClO-. Comprehensive analyses by 1H NMR, TLC, FTIR, HRMS, UV-vis, fluorescence and DFT illustrated that ClO- reacted with the CC bond of DTB, generating fluorophore 2T-CHO, leading to strong blue fluorescence. Interestingly, DTB loaded colorimetric test strips were established for rapid and real-time visual detection of ClO-. Furthermore, the DTB was successfully applied to quantitatively and sensitively detect ClO- in 84 disinfectant, bio-fluids (human serum and urine) and actual water samples. Importantly, the biocompatible DTB has been employed for visualizing and bioimaging ClO- in mung bean sprouts, Arabidopsis, live cells and zebrafish. These investigations demonstrate that DTB has great potentials for detecting ClO- in various biosystems and environments. This work would offer a new idea for developing multifunctional sensors with better performance for chemo/biosensors.

Dataset for the phase equilibria and PXRD studies of urea as a green thermodynamic inhibitor of sII gas hydrates.

The equilibrium conditions of sII methane/propane hydrates have been experimentally determined for the C3H8/CH4-H2O-urea system. The equilibrium dissociation temperatures and pressures of sII hydrates span a wide P,T-range (266.7-293.9 K; 0.87-9.49 MPa) and were measured by varying the feed mass fraction of urea in solution from 0 to 50 mass%. The experimental points at feed urea concentration ≤ 40 mass% correspond to the V-Lw-H equilibrium (gas-aqueous urea solution-gas hydrate). A four-phase V-Lw-H-Su equilibrium (with an additional phase of solid urea) was observed because the solubility limit of urea in water was reached for all points at a feed mass fraction of 50 mass% and for one point at 40 mass% (266.93 K). Gas hydrate equilibria were measured using a high-pressure rig GHA350 under isochoric conditions with rapid fluid stirring and slow ramp heating of 0.1 K/h. Each measured point represents complete dissociation of the sII hydrate. The phase equilibrium data was compared with the literature reported for the C3H8/CH4-H2O and CH4-H2O-urea systems. A comprehensive analysis of the thermodynamic inhibition effect of urea to sII C3H8/CH4 hydrates on pressure and concentration of the inhibitor was carried out. The phase composition of the samples was analyzed by powder X-ray diffractometry at 173 K.

Dataset for the new insights into methane hydrate inhibition with blends of vinyl lactam polymer and methanol, monoethylene glycol, or diethylene glycol as hybrid inhibitors.

Three-phase equilibrium conditions of vapor-aqueous solution-gas hydrate coexistence for the systems of CH4-H2O-organic thermodynamic inhibitor (THI) were experimentally determined. Hydrate equilibrium measurements for systems with methanol (MeOH), monoethylene glycol (MEG), and diethylene glycol (DEG) were conducted. Five concentrations of each inhibitor (maximum content 50 mass%) were studied in the pressure range of 4.9-8.4 MPa. The equilibrium temperature and pressure in the point of complete dissociation of methane hydrate during constant-rate heating combined with vigorous mixing of fluids (600 rpm) in a high-pressure vessel were determined. We compared our experimental points with reliable literature data. The coefficients of empirical equations are derived, which accurately describe hydrate equilibrium conditions for the studied systems. The effect of THI concentration and pressure on methane hydrate equilibrium temperature suppression was analyzed. In the second stage, we studied the kinetics of methane hydrate nucleation/growth in systems containing a polymeric KHI (0.5 mass% of N-vinylpyrrolidone and N-vinylcaprolactam copolymer) in water or THI aqueous solution. For this, temperatures, pressures, and subcoolings of methane hydrate onset were measured by rocking cell tests (RCS6 rig, ramp cooling at 1 K/h). Gas uptake curves characterizing the methane hydrate crystallization kinetics in the polythermal regime were obtained.

Nano-Cavities within Nano-Zeolites: The Influencing Factors of the Fabricating Process on Their Catalytic Activities.

Titanium silicalite-1 (TS-1) is a milestone heterogeneous catalyst with single-atom tetrahedral titanium incorporated into silica framework for green oxidation reactions. Although TS-1 catalysts have been industrialized, the strategy of direct hydrothermal synthesis usually produces catalysts with low catalytic activities, which has still puzzled academic and industrial scientists. Post-treatment processes were widely chosen and were proven to be an essential process for the stable production of the high-activity zeolites with hollow structures. However, the reasons why post-treatment processes could improve catalytic activity are still not clear enough. Here, high-performance hollow TS-1 zeolites with nano-sized crystals and nano-sized cavities were synthesized via post-treatment of direct-synthesis nano-sized TS-1 zeolites. The influencing factors of the fabricating processes on their catalytic activities were investigated in detail, including the content of alkali metal ions, the state of titanium centers, hydrophilic/hydrophobic properties, and accessibility of micropores. The post-treatment processes could effectively solve these adverse effects to improve catalytic activity and to stabilize production. These findings contribute to the stable preparation of high-performance TS-1 catalysts in both factories and laboratories.