Innovation in manufacturing SMEs during the COVID-19 pandemic: How does environmental dynamism reinforce employee proactive behavior?

In a turbulent environment such as during the COVID-19 pandemic crisis, employee proactive behavior is imperative for innovation initiatives in small- and medium-sized enterprises (SMEs). We ask whether and how turbulent environments motivate employees to proactively engage in innovative behavior. This study argues that employees' perceptions of environmental dynamism reinforce employee proactive innovation behavior. Using a sample comprising 262 innovative employees from 40 manufacturing SMEs in Taiwan, this study tests a moderated-mediation model in which environmental dynamism is expected to increase the indirect effect of creative self-efficacy on employee innovative behavior through knowledge acquisition. The results confirm the mediating role of knowledge acquisition and the positive moderating effect of environmental dynamism. This study sheds light on the issue of employee proactive behavior in response to changing environments.

Highly Sensitive, Robust, and Recyclable TiO2/AgNP Substrate for SERS Detection.

Label-free biosensors provide an important platform for detecting chemical and biological substances without needing extra labeling agents. Unlike surface-based techniques such as surface plasmon resonance (SPR), interference, and ellipsometry, surface-enhanced Raman spectroscopy (SERS) possesses the advantage of monitoring analytes both on surfaces and in solutions. Increasing the SERS enhancement is crucial to preparing high-quality substrates without quickly losing their stability, sensitivity, and repeatability. However, fabrication methods based on wet chemistry, nanoimprint lithography, spark discharge, and laser ablation have drawbacks of waste of time, complicated processes, or nonreproducibility in surface topography. This study reports the preparation of recyclable TiO2/Ag nanoparticle (AgNP) substrates by using simple arc ion plating and direct-current (dc) magnetron sputtering technologies. The deposited anatase-phased TiO2 ensured the photocatalytic degradation of analytes. By measuring the Raman spectra of rhodamine 6G (R6G) in titrated concentrations, a limit of detection (LOD) of 10-8 M and a SERS enhancement factor (EF) of 1.01 × 109 were attained. Self-cleaning was performed via UV irradiation, and recyclability was achieved after at least five cycles of detection and degradation. The proposed TiO2/AgNP substrates have the potential to serve as eco-friendly SERS enhancers for label-free detection of various chemical and biological substances.

High Sensitivity SERS Substrate of a Few Nanometers Single-Layer Silver Thickness Fabricated by DC Magnetron Sputtering Technology.

Surface-enhanced Raman spectroscopy (SERS) is commonly used for super-selective analysis through nanostructured silver layers in the environment, food quality, biomedicine, and materials science. To fabricate a high-sensitivity but a more accessible device of SERS, DC magnetron sputtering technology was used to realize high sensitivity, low cost, a stable deposition rate, and rapid mass production. This study investigated various thicknesses of a silver film ranging from 3.0 to 12.1 nm by field emission scanning electron microscope, X-ray diffraction, and X-ray photoelectron spectroscopy. In the rhodamine 6G (R6G) testing irradiated by a He-Ne laser beam, the analytical enhancement factor (AEF) of 9.35 × 108, the limit of detection (LOD) of 10-8 M, and the relative standard deviation (RSD) of 1.61% were better than the other SERS substrates fabricated by the same DC sputtering process because the results showed that the 6 nm thickness silver layer had the highest sensitivity, stability, and lifetime. The paraquat and acetylcholine analytes were further investigated and high sensitivity was also achievable. The proposed SERS samples were evaluated and stored in a low humidity environment for up to forty weeks, and no spectrum attenuation could be detected. Soon, the proposed technology to fabricate high sensitivity, repeatability, and robust SERS substrate will be an optimized process technology in multiple applications.

Optical measurement in a curved optical medium with optical birefringence and anisotropic absorption.

The planar optical mediums with properties of either birefringence (i.e., waveplates) or anisotropic absorption (i.e., polarizers) are well studied. However, how a beam propagates in a birefringent curved medium with anisotropic absorption, especially for curved-sheet polarizers, still needs to be investigated. In this paper, we study optical wave propagation through a curved-birefringent medium with anisotropic absorption. We built an optical model based on the Mueller matrix to predict the spatial distributions in light intensity and polarization when light propagates in a curved-birefringent medium with anisotropic absorption. To demonstrate how to use the optical model, the experiments based on ellipsometry are also performed. The impact of this study is to analyze the light propagation in birefringent-curved medium with anisotropic absorption, which could affect the performance of curved liquid crystal devices with curved polarizers, such as curved liquid crystal displays (LCDs), flexible LCDs, and flexible LC lenses.

Hepatitis B virus persistent infection-related single nucleotide polymorphisms in HLA regions are associated with viral load in hepatoma families.

BACKGROUND: Genome-wide association studies from Asia indicate that HLA-DP and HLA-DQ loci are important in persistent hepatitis B virus (HBV) infections. One of the key elements for HBV-related carcinogenesis is persistent viral replication and inflammation. AIM: To examine genetic and nongenetic factors with persistent HBV infection and viral load in families with hepatocellular carcinoma (HCC). METHODS: The HCC families included 301 hepatitis B surface antigen (HBsAg) carriers and 424 noncarriers born before the nationwide vaccination program was initiated in 1984. Five HBV-related single nucleotide polymorphisms (SNPs) - rs477515, rs9272105, rs9276370, rs7756516, and rs9277535 - were genotyped. Factors associated with persistent HBV infection and viral load were analyzed by a generalized estimating equation. RESULTS: In the first-stage persistent HBV study, all SNPs except rs9272105 were associated with persistent infection. A significantly higher area under the reciprocal operating characteristic curve for nongenetic factors vs genetic factors (P < 0.001) suggests that the former play a major role in persistent HBV infection. In the second-stage viral load study, we added 8 HBsAg carriers born after 1984. The 309 HBsAg carriers were divided into low (n = 162) and high viral load (n = 147) groups with an HBV DNA cutoff of 105 cps/mL. Sex, relationship to the index case, rs477515, rs9272105, and rs7756516 were associated with viral load. Based on the receiver operating characteristic curve analysis, genetic and nongenetic factors affected viral load equally in the HCC family cohort (P = 0.3117). CONCLUSION: In these east Asian adults, the mechanism of persistent HBV infection-related SNPs was a prolonged viral replication phase.

The prevalence of Passavant's ridge in patients with velopharyngeal insufficiency in a Taiwan Chinese population.

BACKGROUND/PURPOSE: The Passavant's ridge can be utilized as a guide landmark during obturator prosthesis fabrication, but there were no studies concerning about the prevalence of the ridge in East Asia region. The purpose of this study was to evaluate the occurrence of Passavant's ridge in patients with velopharyngeal insufficiency in a Taiwan Chinese population. MATERIALS AND METHODS: It's a retrospective study that 91 patients with velopharyngeal insufficiency who received a obturator prosthesis during the period from 1992 to 2016 in Taichung Veterans General Hospital (TCVGH, Taiwan) were included. The Passavant's ridge was directly identified under intraoral examination during phonation (group 1) and gagging (group 2) action by two examiners. The results in these two groups were compared using McNemar test. Associations between the presence of the ridge and categorical variables (gender, etiology and defect area) were also analyzed using the chi-square test or Fisher's exact test. (α = 0.05). RESULTS: Passavant's ridge was observed during phonation in 72 patients (79.1%) and during gagging in 83 patients (91.2%), which showed a statistically difference (p < 0.05). The relationship between the presence of the ridge and categorical variables (gender, etiology and defect area) were evaluated but no statistically significant correlation was found (p > 0.05). CONCLUSION: A high prevalence of Passavan't ridge either in phonation and gagging action was identified in patients with velopharyngeal insufficiency in a Taiwan Chinese population. In addition, the occurrence of Passavant's ridge was significantly higher during gagging action than during phonation.

Effects of sex and generation on hepatitis B viral load in families with hepatocellular carcinoma.

AIM: To explore factors associated with persistent hepatitis B virus (HBV) infection in a cohort of hepatocellular carcinoma (HCC)-affected families and then investigate factors that correlate with individual viral load among hepatitis B surface antigen (HBsAg)-positive relatives. METHODS: We evaluated non-genetic factors associated with HBV replication in relatives of patients with HCC. Relatives of 355 HCC cases were interviewed using a structured questionnaire. Demographics, relationship to index case, HBsAg status of mothers and index cases were evaluated for association with the HBV persistent infection or viral load by generalized estimating equation analysis. RESULTS: Among 729 relatives enrolled, parent generation (P = 0.0076), index generation (P = 0.0044), mothers positive for HBsAg (P = 0.0007), and HBsAg-positive index cases (P = 5.98 × 10-8) were associated with persistent HBV infection. Factors associated with HBV viral load were evaluated among 303 HBsAg-positive relatives. Parent generation (P = 0.0359) and sex (P = 0.0007) were independent factors associated with HBV viral load. The intra-family HBV viral load was evaluated in families clustered with HBsAg-positive siblings. An intra-family trend of similar HBV viral load was found for 27 of 46 (58.7%) families. Male offspring of HBsAg-positive mothers (P = 0.024) and older siblings were associated with high viral load. CONCLUSION: Sex and generation play important roles on HBV viral load. Maternal birth age and nutritional changes could be the reasons of viral load difference between generations.

Integration of Value Stream Map and Healthcare Failure Mode and Effect Analysis into Six Sigma Methodology to Improve Process of Surgical Specimen Handling.

Specimen handling is a critical patient safety issue. Problematic handling process, such as misidentification (of patients, surgical site, and specimen counts), specimen loss, or improper specimen preparation can lead to serious patient harms and lawsuits. Value stream map (VSM) is a tool used to find out non-value-added works, enhance the quality, and reduce the cost of the studied process. On the other hand, healthcare failure mode and effect analysis (HFMEA) is now frequently employed to avoid possible medication errors in healthcare process. Both of them have a goal similar to Six Sigma methodology for process improvement. This study proposes a model that integrates VSM and HFMEA into the framework, which mainly consists of define, measure, analyze, improve, and control (DMAIC), of Six Sigma. A Six Sigma project for improving the process of surgical specimen handling in a hospital was conducted to demonstrate the effectiveness of the proposed model.

Synthesis of an anti-Bredt compound, bicyclo[3.2.2]nona-1,6,8-triene, via the isomerization of tricyclo[3.2.2.0(2,4)]nona-2,6-diene.

A highly strained 1,3-fused tricyclic cyclopropene, tricyclo[3.2.2.0(2,4)]nona-2,6-diene (15), was designed for use in the synthesis of a new highly strained anti-Bredt compound, bicyclo[3.2.2]nona-1,6,8-triene (17). Tricyclic cyclopropene 15 was subjected to a ring-opening reaction followed by insertion of the resulting carbene to produce an anti-Bredt compound 17. The tricyclic cyclopropene 15 was prepared by the fluoride-induced elimination of 2-chloro-3-trimethylsilyltricyclo[3.2.2.0(2,4)]non-6-ene (20), via the reaction of 1-chloro-3-trimethylsilylcyclopropene with 1,3-cyclohexadiene. Both the tricyclic cyclopropene 15 and the anti-Bredt compound 17 were trapped by diphenylisobenzofuran (DPIBF).

A holographic projection system with an electrically tuning and continuously adjustable optical zoom.

A holographic projection system with optical zoom is demonstrated. By using a combination of a LC lens and an encoded Fresnel lens on the LCoS panel, we can control zoom in a holographic projector. The magnification can be electrically adjusted by tuning the focal length of the combination of the two lenses. The zoom ratio of the holographic projection system can reach 3.7:1 with continuous zoom function. The optical zoom function can decrease the complexity of the holographic projection system.

An electrically tunable-focusing liquid crystal lens with a low voltage and simple electrodes.

An electrically tunable focusing LC lens with a low voltage and simple planar electrodes is demonstrated. The inhomogeneous electric field of the LC lens without any hole-patterned-electrode is generated by using an embedded polymeric layer with a gradient distribution of dielectric constants (or relative permittivity). LC directors in the LC layer experience spatially inhomogeneous voltages even though a single voltage is applied to the planar electrodes. Such a LC lens has a low voltage (~2.6 V(rms)) and simple design of electrodes. The gradient distribution of dielectric constants of polymeric layer is discussed and the performance of the LC lens is investigated. The applications of such a LC lens are cell phones, webcam, and pico projectors.

Material and energy balances of an integrated biological hydrogen production and purification system and their implications for its potential to reduce greenhouse gas emissions.

The materials and energy in an integrated biological hydrogen production and purification system involving hydrolysis, dark fermentation, photo fermentation, CO2 fixation and anaerobic digestion are balanced by integrating the results from multiple experiments, simulations and the literature. The findings are two fold. First, using 1000 kg rice straw as a substrate, 19.8 kg H2 and 138.0 kg CH4 are obtained. The net energy balance (NEB) and net energy ratio (NER) are -738.4 kWh and 77.8%, respectively, both of which imply an unfavorable energy production system. Opportunities to improve the performance particularly lie in the photo fermentation process. Second, greenhouse gas emissions are evaluated for various options. The results were comparable with the emission inventory of electricity generated from fossil fuels. NEB and NER under a zero-carbon-emission constraint were discussed in detail to clarify completely the implications of the energy and material balances on greenhouse gas emissions.

An electrically tunable optical zoom system using two composite liquid crystal lenses with a large zoom ratio.

An electrically tunable-focusing optical zoom system using two composite LC lenses with a large zoom ratio is demonstrated. The optical principle is investigated. To enhance the electrically tunable focusing range of the negative lens power of the LC lens for a large zoom ratio, we adopted two composite LC lenses. Each composite LC lens consists of a sub-LC lens and a planar polymeric lens. The zoom ratio of the optical zooming system reaches ~7.9:1 and the object can be zoomed in or zoomed out continuously at the objective distance of infinity to 10 cm. The potential applications are cell phones, cameras, telescope and pico projectors.

An application of artificial immune recognition system for prediction of diabetes following gestational diabetes.

Diabetes mellitus (DM) is a disease prevalent in population and is not easily perceived in its initial stage but may sway a patient very seriously in later stage. In accordance with the estimation of World Health Organization (WHO), there will be 370 million diabetics which are 5.4% of the global people in 2030, so it becomes more and more important to predict whether a pregnant woman has or is likely to acquire diabetes. This study is conducted with the use of the machine learning-Artificial Immune Recognition System (AIRS)-to assist doctors in predicting pregnant women who have premonition of type 2 diabetes. AIRS is proposed by Andrew Watkins in 2001 and it makes use of the metaphor of the vertebrate immune system to recognize antigens, select clone, and memorize cells. Additionally, AIRS includes a mechanism, limited resource, to restrain the number of memory cells from increasing uncontrollably. It has also showed positive results on problems in which it was applied. The objective of this study is to investigate the feasibility in using AIRS to predict gestational diabetes mellitus (GDM) subsequent DM. The dataset of diabetes has imbalanced data, but the overall classification recall could still reach 62.8%, which is better than the traditional method, logistic regression, and the technique which is thought as one of the powerful classification approaches, support vector machines (SVM).

Response surface optimization of dissolved oxygen and nitrogen sources for the biodegradation of MTBE and BTEX.

Response surface methodology (RSM) using central composite design was applied to obtain the optimal dissolved oxygen (DO) and nitrogen (N) concentrations for biodegrading MTBE (Methyl tert-butyl ether) and BTEX (benzene, ethylbenzene, toluene, p-xylene). Moreover, the effects of DO, N, and their interaction on the degradation process were evaluated. It was found that N, N(2), DO and DO(2) have significant effects on the efficiency of MTBE and BTEX removal. The removal efficiency when using biostimulation with bioaugmentation (BwB) is higher than with other processes, being greater than 82% at concentrations of 12 and 48 mg l(-1) for DO and N, respectively. However, it was also found that the interaction term of DO x N has no significant effect on the degradation processes.

Electrically tunable wettability of liquid crystal/polymer composite films.

An electrically tunable wettability in a liquid crystal/ polymer composite film is demonstrated, in which liquid crystal molecules are anchored among polymer grains. The tunable wettability of the composite films originates from the reorientation of the anchored liquid-crystal molecules, which is switched by an in-plane electric field with squared pulses of voltages. These liquid crystal/polymer composite films with electrically tunable wettability have potential applications in polarizer-free displays, ink-jet printing, microfluidic devices, and lab-on-a-chip.

Electroosmotic flow velocity measurements in a square microchannel.

Experiments were performed using a microparticle image velocimetry (MPIV) for 2D velocity distributions of electroosmotically driven flows in a 40-mm-long microchannel with a square cross section of 200×200 µm. Electroosmotic flow (EOF) bulk fluid velocity measurements were made in a range of streamwise electric field strengths from 5 to 25 kV/m. A series of seed particle calibration tests can be made in a 200×120×24,000-µm untreated polydimethyl siloxane (PDMS channel incorporating MPIV to determine the electrophoretic mobilities in aqueous buffer solutions of 1× TAE, 1× TBE, 10 mM NaCl, and 10 mM borate. A linear/nonlinear (due to Joule heating) flow rate increase with applied field was obtained and compared with those of previous studies. A parametric study, with extensive measurements, was performed with different electric field strength and buffer solution concentration under a constant zeta potential at wall for each buffer. The characteristics of EOF in square microchannels were thus investigated. Finally, a composite correlation of the relevant parameters was developed in the form of [Formula: see text] within ±1% accuracy for 99% of the experimental data.