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The utilization of solid waste as a resource is a beneficial approach to achieve pollution reduction and carbon reduction simultaneously. In this paper, we developed a quaternary solid waste-based cementitious materials (SWCMs) that can be used as a substitute for cement by utilizing four types of solid waste, namely ground granulated blast furnace slag (GGBS), steel slag (SS), ammonia-soda residue (ASR) and desulfurization gypsum (DG). The performance optimization and carbon emissions of SWCMs are investigated by response surface methodology and emission factor calculations. The results showed that a second-order polynomial model can accurately predict the compressive strength of mortar specimens of SWCMs, with prediction accuracies of 96.78 % and 87.17 % for compressive strengths at 3 days and 28 days, respectively. In terms of raw materials, DG content positively correlates with the compressive strength of the mortar containing SWCMs, moreover, ratios of GGBS to ASR of less than two or more than eight are beneficial. In addition, the production process of each ton of SWCMs emits 71.51 kg CO2, which is only 10 % of the production process of ordinary Portland cement. Overall, this work elucidates the influence of raw materials on the mechanical properties of quaternary SWCMs and quantifies their carbon reduction effects as a substitute for traditional cement, advancing the investigation and application of SWCMs in the realm of low-carbon materials.

Summary: The nuclear factor-kappa B (NF-κB) pathway is an evolutionarily conserved signaling pathway that plays a central role in immune responses and inflammation. Here, we show that Drosophila NF-κB signaling is activated via a pathway in parallel with the Toll receptor by receptor-type guanylate cyclase, Gyc76C. Gyc76C produces cyclic guanosine monophosphate (cGMP) and modulates NF-κB signaling through the downstream Tollreceptor components dMyd88, Pelle, Tube, and Dif/Dorsal (NF-κB). The cGMP signaling pathway comprises a membrane-localized cGMP-dependent protein kinase (cGK) called DG2 and protein phosphatase 2A (PP2A) and is crucial for host survival against Gram-positive bacterial infections in Drosophila. A membrane-bound cGK, PRKG2, also modulates NF-κB activation via PP2A in human cells, indicating that modulation of NF-κB activation in innate immunity by the cGMP signaling pathway is evolutionarily conserved.

With the advancement of communication technology, online synchronous exercise courses become more common in recent years due to their ability to transcend time and space. Based on uses and gratifications theory (U&G), this study proposes a conceptual model for online synchronized exercise classes and examines the relationships among social inhibition, motivation, satisfaction, and continued involvement. After 322 valid questionnaires were collected and analyzed by partial least squares (PLS), this study confirmed the significant positive effects of hedonic, identified, and integrative motivation on online synchronous exercise satisfaction and the significant negative effect of social inhibition on online synchronous exercise satisfaction. Moreover, online synchronous exercise satisfaction has a positive effect on enduring involvement. This study not only contributes by extending the application of U&G theory to dynamic online synchronized exercise and addressing the interaction and pressure of online users in cyberspace but also provides novel marketing strategies for fitness and sports organizations.

Background/Purpose: Pseudomonas aeruginosa bacteremia is an important cause of nosocomial infections with high morbidity and mortality. Time-to-positivity (TTP) of blood cultures is considered to be a predictor of the clinical outcome for bacteremia. The aim of the study is to investigate the relationship between TTP and clinical outcomes in patients with monomicrobial P. aeruginosa bacteremia. Methods: From January 2013 to June 2014, a retrospective cohort study was conducted in a 1200-bed tertiary care hospital. The cases of monomicrobial P. aeruginosa bacteremia were studied. TTP and clinical parameters were determined and analyzed. Results: In 139 cases of P. aeruginosa bacteremia, TTP ≤ 13 hours was associated with higher Pitt bacteremia scores (5.3 ± 4.2 vs. 2.3 ± 2.8, p

This study attempted to manage the food waste and soybean curd residue generated in Taiwan's National Ilan University by black soldier fly-aided co-composting. The food waste and soybean curd residue were co-composted with rice husk as a bulking agent in 4:1 ratio and 0.42 mg BSF/g waste. The higher organic matter degradation of 31.9% was found in Container B (black soldier flies aided food waste and rice husk co-composting) with a rate constant of 0.14 d -1 . In Container D (black soldier flies aided soybean curd residue and rice husk co-composting), the organic matter degradation of 29.4% was found with a rate constant of 0.29 d -1 . The matured compost of 6.02 kg was obtained from 20 kg of food waste, while 5.83 kg of matured compost was generated from 20 kg of soybean curd residue. The physico-chemical parameters of the final matured compost were in the favorable range of Taiwan's compost standards. The germination index was 188.6% and 194.78% in Containers B and D, respectively. The present study will expand the application of BSF at the institutional level which prove to be a feasible solution for rapid, clean, and efficient composting of post-consumer food wastes., (Copyright © 2022 Elsevier Inc. All rights reserved.)

In this study, we developed an innovative spherical biochar with high porosity and excellent paracetamol (PRC) adsorption capacity. The optimal pyrolysis temperatures for the preparation of spherical biochar (derived from pure glucose) and non-spherical biochar (from pomelo peel wastes) were obtained at 900 °C and 700 °C, respectively. Various advanced techniques were applied to characterize the prepared biochars. Spherical and non-spherical biochars exhibited large specific surface area (1292 and 1033 m 2 /g) and high total pore volume (0.704 and 1.074 cm 3 /g), respectively. The adsorption behavior of PRC onto two biochars was conducted utilizing batch experiments. Results demonstrated that the adsorption process was slightly affected by the change of solution pH (2-11) and addition of NaCl (0.05-1.0 M) and was able to achieve fast equilibrium (∼120 min). The maximum adsorption capacity of spherical biochar (286 mg/g) for PRC was approximately double that of non-spherical biochar (147 mg/g). The signal of thermodynamic parameters was negative ΔG° and ΔH° values, but positive ΔS° value. The adsorption mechanism consisted of pore-filling, hydrogen bonding formations, n-π and π-π interactions, and van der Waals force. The adsorption capacities of two biochars were insignificantly dependent on different real water samples containing PRC. Consequently, the biochars can serve as a green and promising material for efficiently removing PRC from water., (Copyright © 2020. Published by Elsevier B.V.)

Estuaries are areas of both freshwater and seawater that are partially enclosed with contact to the open sea and a flow of fresh water. Although the Jiulong River Estuary has a relatively small catchment, this area was found to exhibit high nutrient fluxes. The nutrient fluxes showed obvious fluctuations for different years. The Jiulong River Estuary was predominantly P-limited, and was slowly moving towards higher DIN:DIP and DSi:DIP ratios as the nitrate concentrations increased. The high nutrient fluxes into the estuary may affect estuarine ecosystems by the alteration of DO concentrations in bottom waters, causing harm to benthic fauna due to a lack of oxygen, triggering algal blooms. Additionally, the Jiulong River Estuary was slowly moving towards lower DSi:DIN and DSi:DIP ratios along with the change of time scales, which caused nutrient limitation of phytoplankton growth as P and Si levels decreased and became more limiting., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Particles are often too small to be separated from a reaction system and recycled, especially in wastewater treatment via a catalytic ozonation process. Thus, the objective of this study was to prepare a magnetic catalyst (SiO(2)/Fe(3)O(4)) that can be recycled by using an external magnetic field. The effects of the characteristics of the magnetic catalyst, pH values, catalyst dosage, and initial concentration of Reactive Black 5 (RB5) on mineralization efficiency of the magnetic catalyst/H(2)O(2)/O(3) process were also investigated. The mineralization efficiency of RB5 under various conditions followed the sequence: SiO(2)/Fe(3)O(4)/H(2)O(2)/O(3)>SiO(2)/Fe(3)O(4)/O(3)>Fe(3)O(4)/O(3) approximately H(2)O(2)/O(3)>O(3)>SiO(2)/Fe(3)O(4)/H(2)O(2). Given the results of our reuse and recovery experiments, the magnetic catalyst shows considerable promise for use in water treatment.

To obtain a minimum feeding rate (F(min)) of activated carbon (AC), a series of measurements on dioxin emission concentration were carried out in a large-scale municipal solid waste incinerator. It was found that dioxin removal efficiency (eta) increased with an increase in AC feeding concentration. This had an almost linear function to F/Q when F/Q was less than 65 g/Nm(3), where F was the AC feeding rate (mg/min), and Q was the volumetric flow rate of flue gas (Nm(3)/min). However, it did not seem to be affected by F/Q, when F/Q was larger than 150 mg/Nm(3). On the basis of the experimental data obtained in this study, the removal efficiency of dioxins by the application of AC could be correlated as eta (%)=100/[1.0+(40.2/(F/Q)(3))]. It is valid in appropriate conditions (F/Q=10-300 mg/Nm(3)) suggested by the study with a statistical error of +/-18%. The correlation would be applied to estimate the dioxin removal efficiency (eta) using the F/Q value. For engineering applications, the (F/Q)(min) could be solved using a graphic illustration method, by which the minimum feeding rate (F) was obtained if the flue gas volumetric flow rate (Q) was known.

This study investigates the toxicity of various pollutant species from motorcycle exhaust via dose-response analysis and margin of safety using Escherichia coli DH5 alpha. The toxicity evaluation of the major components of motorcycle exhaust volatile organic compounds (VOCs), collected with impinger, and polycyclic aromatic hydrocarbons (PAHs), collected with filter and XAD-2, is essential to determine emission standards for motorcycles. The toxicity of benzene (B), toluene (T), ethyl benzene (E) and xylene (X) was selected for comparison as standard VOCs emitted from motorcycles. In addition, three types of reformulated gasoline (high oxygenate and high benzene content (No. 1), low oxygen and high benzene (No. 2), and low oxygen and low benzene (No. 3) were prepared to reveal combined toxicity of individual compositions. Motorcycle exhaust is significantly more toxic than BTEX due to the highly toxic VOCs generated from incomplete combustion. Overall toxicity evaluation showed that the toxicity, indicated as EC50, was approximately as follows: PAHs>two-stroke engines>four-stroke engines>BTEX.

This study evaluated the performance of a photoreactor packed with TiO2/glass, TiO2 immobilized on glass beads, initiated by UV irradiation, denoted as UV/TiO2/glass, to decompose di-n-butyl phthalate (DBP) in an aqueous solution. The photodegradation rate of DBP by this UV/TiO2/glass process was found to obey pseudo first-order kinetics represented by the Langmuir-Hinshelwood model. The experimental results of this study show that the influence of pH value of an aqueous solution to reaction rate was negligible at the pH values 4.5-9. The effect of cations on the photodegradation rate of DBP reveals that the larger the charge and size of cations contained, the more the inhibition of reaction rate increased. The UV/TiO2/glass process yielded a 75% degradation efficiency of DBP with initial concentration of 5 mg L(-1) at 80 min reaction time.

This study evaluated the performance of photo-Fenton reaction initiated by the UV irradiation with H(2)O(2)/Fe(3+), denoted as UV/H(2)O(2)/Fe(3+), to decompose di-n-butyl phthalate (DBP) in the aqueous solution. The concentration of total organic carbon (TOC) was chosen as a mineralization index of the decomposition of DBP by the UV/H(2)O(2)/Fe(3+) process. A second-order kinetic model with respect to TOC was adequately adopted to represent the mineralization of DBP by the UV/H(2)O(2)/Fe(3+) process. The experimental results of this study suggested that the dosages with 4.74 x 10(-5) mol min(-1)L(-1) H(2)O(2) and initial Fe(3+) loading concentration of 4.50 x 10(-4) mol L(-1) in the solution at pH 3.0 with 120 microW cm(-2) UV (312 nm) provided the optimal operation conditions for the mineralization of DBP (5 mg L(-1)) yielding a 92.4% mineralization efficiency at 90 min reaction time.

In order to recover valuable materials and to minimize the adverse effects of hazardous materials contained in scrap computers, a dismantling practice is commonly adopted to treat scrap computers. By using the dismantling process, both useful and hazardous materials can be manually separated and retrieved. On the basis of the properties of the retrieved materials, they can be sent to appropriate facilities for further recycling or treatment. Among the retrieved materials, the treatment of hazardous materials from cathode ray tubes (CRT) and printed circuit boards with integrated circuits have drawn considerable attention, thus implying that the proper treatment of such materials can greatly assure the successful recycling of scrap computers. For this reason, this study reviews the available technologies which can be applied to treat and recycle cathode ray tube components and printed circuit boards with integrated circuits. Actual recycling data from a scrap computer recycling plant located in Taiwan are also introduced. The data show that this recycling plant can recover 94.75 wt. % and 45.99 wt. % of useful materials from the main machines (i.e., CPU, power supplier, fan, IC boards, DVD drive, CD drive, hard disk, soft disk, shell casing, etc.) and monitors of scrap computers, respectively.

Atmospheric concentrations of chlorine atom (Cl*), chlorine monoxide radical (ClO*), and hydroxyl radical (HO*) in the coastal marine boundary layer are estimated in this study. A steady-state approach to their concentrations in equilibrium with other atmospheric chemical species is used. Measurements of atmospheric trace species, HCl, Cl2, HCHO, H2O2, CH3OOH, CH4, CO, SO2, NO, NO2, and O3, were performed at four sites in Taiwan during the spring of 1999. The results indicate that the concentrations of the Cl* atom and the ClO* and HO* radicals decrease significantly with cloud cover. The calculated average daytime concentrations of Cl*, ClO*, and HO* are 3 x 10(5), 1 x 10(7), and 6 x 10(5) molecules/cm3, respectively. Due to the high reactivity of Cl* with hydrocarbons and its concentration level competitive to that of HO*, Cl* should be a significant sink for hydrocarbons in these cases.