Distinguished denitrifying phosphorus removal in the high-rate anoxic/microaerobic system for sewage treatment.

This study re-evaluated the role of anoxic and anaerobic zones during the enhanced biological phosphorus (P) removal process by investigating the potential effect of introducing an anoxic zone into a high-rate microaerobic activated sludge (MAS) system (1.60-1.70 kg chemical oxygen demand (COD) m-3 d-1), i.e., a high-rate anoxic/microaerobic (A/M) system for sewage treatment. In the absence of a pre-anaerobic zone, introducing an anoxic zone considerably reduced effluent NOx--N concentrations (7.2 vs. 1.5 mg L-1) and remarkably enhanced total nitrogen (75% vs. 89%) and total P (18% vs. 60%) removal and sludge P content (1.48% vs. 1.77% (dry weight)) due to further anoxic denitrifying P removal in the anoxic zone (besides simultaneous nitrification and denitrification in the microaerobic zone). High-throughput pyrosequencing demonstrated the niche differentiation of different polyphosphate accumulating organism (PAO) clades (including denitrifying PAO [DPAO] and non-DPAO) in both systems. Introducing an anoxic zone considerably reduced the total PAO abundance in sludge samples by 42% and modified the PAO community structure, including 17-19 detected genera. The change was solely confined to non-DPAOs, as no obvious change in total abundance or community structure of DPAOs including 7 detected genera was observed. Additionally, introducing an anoxic zone increased the abundance of ammonia-oxidizing bacteria by 39%. The high-rate A/M process provided less aeration, higher treatment capacity, a lower COD requirement, and a 75% decrease in the production of waste sludge than the conventional biological nutrient removal process.

Population genetics provides insights into the important agronomic traits of Ganoderma cultivation varieties in China.

This study aimed to investigate the species diversity and genetic differentiation of the genome of the main cultivated strains of Ganoderma in China. Population genomics analysis was conducted based on 150 cultivated strains of Ganoderma collected nationwide. The results indicated that the main species currently cultivated in China were Ganoderma sichuanense and Ganoderma lucidum, with a minor proportion of Ganoderma sessile, Ganoderma weberianum, Ganoderma sinense, Ganoderma gibbosum and Ganoderma australe. A total of 336,506 high-quality single nucleotide polymorphism (SNP) loci were obtained through population evolution analysis. The Fst values were calculated using a 5-kb sliding window, which ranged from 0.11 to 0.74. This suggests varying degrees of genetic differentiation between populations and genetic exchange among varieties. On this basis, the genes related to the stipe length, cap color and branch phenotypes of Ganoderma were excavated, and the region with the top 1% ZFst value region was used as a candidate region. A total of 137, 270 and 222 candidate genes were identified in the aforementioned 3 phenotypes, respectively. Gene annotation revealed that genes associated with stipe length were mainly related to cell division and differentiation, including proteins such as Nse4 protein and DIM1 protein. The genes related to Ganoderma red color were mainly related to the metabolism of tryptophan and flavonoids. The genes related to the branch were mainly related to cytokinin synthesis, ABC transporter and cytochrome P450. This study provided 150 valuable genome resequencing data in assessing the diversity and genetic differentiation of Ganoderma and laid a foundation for agronomic trait analysis and the development of new varieties of Ganoderma.

Reevaluating the accuracy and specificity of EDTA-based polyphosphate quantification method.

Feng et al. (2020) developed a simple, nondestructive, and cost-effective method to quantify polyphosphate (poly-P) in poly-P-accumulating organism (PAO)-enriched sludge samples through 30-h anaerobic exposure to 1 % (w/v) ethylenediaminetetraacetic acid (EDTA). This study optimized the N/P ratio (∼2) of the PAO culture medium in order to provide excess P for poly-P formation in PAO cells. Subsequently, the fluorescence microscopic observation of stained cells confirmed that Corynebacterium glutamicum was a PAO species capable of heterotrophic nitrification. Finally, this study reevaluated the accuracy and specificity of the EDTA-based quantification method, using two confirmed PAO biomass, three confirmed non-PAO biomass, and two sludge samples. The 1 % (w/v) EDTA treatment appears destructive to non-PAO cells, causes the release of other P forms, and is not effective for all PAO species. Under the conditions, the actual P release amount should be calculated by subtracting approximately 8 mg P g-1 total suspended solids from the determination. The amounts of P released from sludge samples was determined not only by the PAO fractions described by Feng et al. but also by PAO community structure and sludge P content.

A mechanistic study identifying improved technology critical metal delamination from printed circuit boards at lower power sonications in a deep eutectic solvent.

Deep eutectic solvents (DESs) are an emerging class of ionic liquids that offer a solution to reclaiming technology critical metals (TCMs) from electronic waste, with potential for improved life cycle analysis. The high viscosities typical of DESs, however, impose mass transport limitations such that passive TCM removal generally requires immersion over extended durations, in some cases in the order of hours. It is postulated that, through the targeted application of power ultrasound, delamination of key structures in electronic components immersed in DESs can be significantly accelerated, thereby enabling rapid recovery of TCMs. In this paper, we fully characterise cavitation in a Choline Chloride-Ethylene Glycol DES as a function of sonotrode input power, by the acoustic detection of the bubble collapse shockwave content generated during sonications at more than 20 input powers over the available range. This justifies the selection of two powers for a detailed study of ultrasonically enhanced TCM-delamination from printed circuit boards (PCBs). Dual-perspective high-speed imaging is employed, which facilitates simultaneous observation of TCM removal, and the cavitation evolution and interaction with the PCB surface. Bubble jetting is identified as a key contributor to initial pitting of the TCM layers, exposing the larger underlying copper layer, with the contributions of additional inertial cavitation-mediated phenomena such as bubble-collapse shockwaves also demonstrated as important for delamination. Optimal cavitation activity throughout the sonication then promotes etching of the copper base layer of the PCB structure targeted by the DES, liberating the overlaying TCMs in sections as large as 0.79 mm2. We report a thirtyfold improvement in processing time compared to passive delamination, with sonications at the lower power outperforming those at the higher power. The results demonstrate the potential for industrially scalable recovery of TCMs from the growing quantities of global e-waste, using combined power ultrasonics and DESs.

Metabolic inhibitor-free assessment of the heterotrophic ammonia-oxidizing activity in activated sludge.

When the contributions of three ammonia-oxidizing pathways (heterotrophic or autotrophic aerobic ammonia oxidization, and anammox) to wastewater biological nitrogen removal systems was compared by determining their ammonia-oxidizing activities, the key question is how to accurately determine the potential heterotrophic aerobic ammonia-oxidizing (PHAe) activity when the potential autotrophic aerobic ammonia-oxidizing (PAAe) activity (by ammonia-oxidizing bacteria (AOB) or archaea, or complete ammonia oxidization bacteria) also contributes to ammonia oxidization in PHAe activity assay medium. Using a AOB species and three heterotrophic AOB species as inocula, we demonstrated the feasibility of PHAe activity evaluation in the absence of a metabolic inhibitor, i.e., by subtracting the PAAe activity determined in PAAe activity assay medium from a combination of PAAe and PHAe activity determined in PHAe activity assay medium. Binary organic carbon sources (i.e., glucose and acetate) were included in the PHAe activity assay medium to fulfill the carbon requirements of most heterotrophic AOB genera. Higher ammonia-oxidizing activity in AOB biomass than heterotrophic AOB biomass (35.6 vs. 2.6-10.0 mg NH4+-N g-1 MLSS h-1) provides the remarkable advantages of autotrophic aerobic ammonia oxidization in biological nitrogen removal systems. Ammonia removal in three full-scale biological nitrogen removal systems for sewage treatment was predominantly mediated by PAAe activity (1.9-3.3 vs. 0.0-0.3 mg NH4+-N g1 MLSS h-1).

Distinguished denitrifying phosphorus removal in the high-rate anoxic/microaerobic system for sewage treatment.

This study re-evaluated the role of anoxic and anaerobic zones during the enhanced biological phosphorus (P) removal process by investigating the potential effect of introducing an anoxic zone into a high-rate microaerobic activated sludge (MAS) system (1.60-1.70 kg chemical oxygen demand (COD) m-3 d-1), i.e., a high-rate anoxic/microaerobic (A/M) system for sewage treatment. In the absence of a pre-anaerobic zone, introducing an anoxic zone considerably reduced effluent NOx--N concentrations (7.2 vs. 1.5 mg L-1) and remarkably enhanced total nitrogen (75% vs. 89%) and total P (18% vs. 60%) removal and sludge P content (1.48% vs. 1.77% (dry weight)) due to further anoxic denitrifying P removal denitrification in the anoxic zone (besides simultaneous nitrification and denitrification in the microaerobic zone). High-throughput pyrosequencing demonstrated the niche differentiation of different polyphosphate accumulating organism (PAO) clades (including denitrifying PAO [DPAO] and non-DPAO) in both systems. Introducing an anoxic zone considerably reduced the total PAO abundance in sludge samples by 42% and modified the PAO community structure, including 17-19 detected genera. The change was solely confined to non-DPAOs, as no significant change in total abundance or community structure of DPAOs including seven detected genera was observed. Additionally, introducing an anoxic zone increased the abundance of ammonia-oxidizing bacteria by 39%. The high-rate A/M process provided less aeration, higher treatment capacity, a lower COD requirement, and a 75% decrease in the production of waste sludge than the conventional biological nutrient removal process.

Multivariate optimization of characteristic parameters of continuous-flow system with a front buffer tank for industrial reverse osmosis concentrate treatment.

Industrial reverse osmosis concentrate (ROC) was electrochemically oxidized using a continuous-flow system (CFS) with a front buffer tank. Multivariate optimization including Plackett-Burman (PBD) and central composite design based on response surface method (CCD-RSM) was implemented to investigate the effects of characteristic (e.g., recirculation ratio (R value), ratio of buffer tank and electrolytic zone (RV value)) and routine (e.g., current density (i), inflow linear velocity (v) and electrode spacing (d)) parameters. R, v values and current density significantly influenced chemical oxygen demand (COD) and NH4+-N removal and effluent active chlorine species (ACS) level, while electrode spacing and RV value had negligible effects. High chloride content of industrial ROC facilitated the generation of ACS and subsequent mass transfer, low hydraulic retention time (HRT) of electrolytic cell improved the mass transfer efficiency, and high HRT of buffer tank prolonged the reaction between the pollutants and oxidants. The significance levels of COD removal, energy efficiency, effluent ACS level and toxic byproduct level CCD-RSM models were validated by statistical test results, including higher F value than critical effect value, lower P value than 0.05, low deviation between predicted and observed values, and normal distribution of calculated residuals. The highest pollutant removal was achieved at a high R value, a high current density and a low v value; the highest energy efficiency was achieved at a high R, a low current density and a high v value; the lowest effluent ACS and toxic byproduct levels were achieved at a low R value, a low current density and a high v value. Following the multivariate optimization, the optimum parameters were decided to be v = 1.2 cm h-1, i ≥ 8 mA cm-2, d ≥ 4, RV = 10-20 and R = 1 to achieve better effluent quality (i.e., lower effluent pollutant, ACS and toxic byproduct levels).

A Comparison Study of Impulsiveness, Cognitive Function, and P300 Components Between Gamma-Hydroxybutyrate and Heroin-Addicted Patients: Preliminary Findings.

Purpose: The aim of this study was to investigate and compare impulsiveness, negative emotion, cognitive function, and P300 components among gamma-hydroxybutyrate (GHB)-addicted patients, heroin-dependent patients, and methadone maintenance treatment (MMT) subjects. Methods: A total of 48 men including 17 GHB addicts, 16 heroin addicts, 15 MMT subjects, and 15 male mentally healthy controls (HC) were recruited. All subjects were evaluated for symptoms of depression, anxiety, impulsiveness, and cognitive function through the Patient Health Questionnaire (PHQ-9), the Generalized Anxiety Disorder 7-item (GAD-7), the Barratt Impulsiveness Scale version II (BIS-II), the Beijing version of the Montreal Cognitive Assessment (BJ-MoCA), the behavioral test (response time), and event-related potential P300 detection. Results: (1) The mean scores of BIS-II in the GHB addiction group, heroin dependence group, and MMT group were significantly higher than those of the HC group (F = 30.339, P = 0.000). (2) The total scores of BJ-MOCA in GHB addiction group was the worst among the four groups, followed by heroin addiction, MMT group and HC group (F = 27.880, P = 0.000). (3) The response time in the GHB addiction group was the longest among the four groups, followed by the heroin addiction, MMT, and HC groups (F = 150.499, P = 0.000). (4) The amplitude and latency of P300 in GHB addiction subjects were significantly lower and longer than those of the MMT group and the HC group. (5) For the three types of addiction, the P300 amplitudes at Fz, Cz, Pz, T5, and T6 were negatively correlated with the scores of GAD-7, PHQ-9, and BIS-II; the P300 latencies were positively correlated with the response time and negatively correlated with the scores of the BJ-MoCA. Conclusion: People with an addiction were likely to have increased impulsiveness. The cognitive function of the GHB and heroin-addicted subjects, including the heroin detoxification and the MMT groups, was severely impaired, especially for the GHB-addicted patients. The impairment manifested as abnormalities of BJ-MoCA, response time, and P300 components.

Analysis of the Relevant Vital Signs and Infection of Sepsis Patients and to Explore the Influencing Factors of Acute Lung Injury/Acute Respiratory Distress Syndrome.

In order to analyze the relevant vital signs and infection of sepsis patients, the influencing factors of acute lung injury/acute respiratory distress syndrome (ALI/ARDS) are explored. A total of 142 sepsis patients admitted to our hospital from January 2019 to January 2022 are divided into an ALI/ARDS group and a non-ALI/ARDS group according to the incidence of ALI/ARDS. Logistic analysis showed that pulmonary/abdominal infection, fungal origin of infection, Acinetobacter baumannii, low oxygenation index, high blood lactic acid value, APACHE II score, SOFA score, and LIPS score are the risk factors for sepsis-induced ALI/ARDS. The results indicate that pulmonary/abdominal infection, fungal origin of infection, Acinetobacter baumannii, low oxygenation index, high blood lactic acid, APACHE II score, SOFA score, and LIPS score are the risk factors for sepsis induced ALI/ARDS.

Impact of dissolved oxygen and loading rate on NH3 oxidation and N2 production mechanisms in activated sludge treatment of sewage.

Microaerobic activated sludge (MAS) is a one-stage process operated at 0.5-1.0 mg l-1 dissolved oxygen (DO) aiming at simultaneous nitrification and denitrification. We used molecular techniques and a comprehensive nitrogen (N)-transformation activity test to investigate the dominant NH3 -oxidizing and N2 -producing mechanism as well as the dominant ammonia-oxidizing bacteria (AOB) species in sludge samples individually collected from an MAS system and a conventional anoxic/oxic (A/O) system; both systems were operated at a normal loading rate (i.e. 1.0 kg chemical oxygen demand (COD) m-3  day-1 and 0.1 kg NH4 + -N m-3  day-1 ) in our previous studies. The DO levels in both systems (aerobic: conventional A/O system; microaerobic: MAS system) did not affect the dominant NH3 -oxidizing mechanism or the dominant AOB species. This study further demonstrated the feasibility of a higher loading rate (i.e. 2.30 kg COD m-3  day-1 and 0.34 kg NH4 + -N m-3  day-1 ) with the MAS process during sewage treatment, which achieved a 40% reduction in aeration energy consumption than that obtained in the conventional A/O system. The increase in loading rates in the MAS system did not affect the dominant NH3 -oxidizing mechanism but did impact the dominant AOB species. Besides, N2 was predominantly produced by microaerobic denitrification in the MAS system at the two loading rates.

On the thermodynamic behaviors and interactions between bubble pairs: A numerical approach.

Thermodynamic behaviors and interactions between bubble pairs are important to better understand the cavitation phenomena. In this study, a compressible two-phase model, accounting for thermal effects to investigate the thermodynamic behaviors and interactions between bubble pairs, is developed in OpenFOAM. The volume of fluid (VOF) method is adopted to capture the interface. Validations are performed by comparing the simulation results of a single bubble and bubble pairs with corresponding experimental data. The dynamical behaviors of bubble pairs and their thermodynamic effect at different relative distances γ are investigated and discussed, which help reveal the bubble cloud dynamics. The quantitative analysis of γ effects on the maximum temperature during bubble collapse is performed with three distinct stages identified. For a single bubble collapsing near the rigid surface, the thermodynamic characteristics at different relative distances are similar to that of the bubble pairs, but the maximum temperature is higher since the single bubble can collapse to a smaller volume.

Evaluation of the Nutrient Composition, In Vitro Fermentation Characteristics, and In Situ Degradability of Amaranthus caudatus, Amaranthus cruentus, and Amaranthus hypochondriacus in Cattle.

The amaranth plants showed high potential feed value as forage for ruminants. An in-depth study of this plant, particularly in cattle, will help extend its utilization as an alternative protein and fiber feed source in cattle feeding. In this study, the nutrient compositions of three different species of amaranth, Amaranthus caudatus L., Amaranthus cruentus L., and Amaranthus hypochondriacus L.-two varieties for each species, A.ca 74, A.ca 91, A.cu 62, A.cu 66, A. hy 30, and A. hy 48-were evaluated. The in vitro technique was used to evaluate the fermentation characteristics such as total gas production, total volatile fatty acids (VFA) concentration, pH, and ammonia concentration of the rumen fluid. Moreover, the effective degradabilities of dry matter (EDDM) and crude protein (EDCP) of the amaranth forages were determined through in situ bag technique. The amaranth forages: A. caudatus, A. cruentus, and A. hypochondriacus showed better nutritive value than the locally produced forages in Chungcheong province of Korea. The CP of the amaranth ranged from 11.95% to 14.19%, and the neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents ranged from 45.53% to 70.88% and 34.17% to 49.83%, respectively. Among the amaranth varieties, A. hypochondriacus 48 showed the most excellent ruminant feed nutrient quality (CP, 14.19%; NDF, 45.53%; and ADF, 34.17%). The effective degradabilities of dry matter (EDDM; 33-56%) and crude protein EDCP (27-59%) of the amaranth were lower compared to other studies, which could be due to the maturity stage at which the forages were harvested. Nonetheless, A. hypochondriacus 48 showed the highest EDDM (56.73%) and EDCP (59.09%). The different amaranth species did not differ greatly in terms of total VFA concentration or molar proportions, total gas production, or ammonia-N concentration. The high nutrient composition, and highly effective degradability of dry matter and crude protein, coupled with the favorable fermentation characteristics, suggest that the amaranth forages showed good to excellent feed quality for cattle.

Achieving low-cost, highly selective nitrate removal with standard anion exchange resin by tuning recycled brine composition.

This study demonstrated the presence of a critical equivalent ratio of the competing anion (i.e., sulfate and bicarbonate) to chloride ion in recycled brine to achieve highly-selective nitrate removal from nitrate-rich groundwater in the standard-anion exchange resin (AER) (i.e., with trimethylamine functional groups) column process. With increasing bicarbonate (or sulfate):chloride equivalent ratio in brine used to circularly activate/regenerate the standard-AER column, considerable bicarbonate (sulfate) removal and dumping were observed. The critical bicarbonate (sulfate):chloride equivalent ratio of 2:5 (8:1) in brine effectively achieved zero net bicarbonate (sulfate) removal (<5%) from feedwater during long-term exhaustion-regeneration cyclic operation. The feed rate (6-18 BV/h) played a key role in determining the critical sulfate:chloride equivalent ratio in brine, while the feed sulfate concentration (145-345 mg/L) slightly changed the critical sulfate:chloride equivalent ratio. The use of optimized ternary brine (with a sulfate:chloride:bicarbonate equivalent ratio of 42:5:2) stably achieved long-term highly-selective nitrate removal from groundwater in the standard-AER column process with brine electrochemical treatment. The possible mechanism for nitrate selectivity included the modification of the sulfate: and bicarbonate:chloride equivalent ratios in the standard-AER column by the optimized brine in circular activation/regeneration mode; this changed the column elution and breakthrough curves, inhibited the competition of sulfate and bicarbonate for ion exchange sites during exhaustion according to the separation factor, and finally achieved selective nitrate removal from feedwater.

In Situ Growth of Leakage-Free Direct-Bridging GaN Nanowires: Application to Gas Sensors for Long-Term Stability, Low Power Consumption, and Sub-ppb Detection Limit.

Direct-bridge growth of aligned GaN nanowires (NWs) over the trench of GaN-coated sapphire substrate was realized in which the issues of parasitic deposition and resultant bypass current were resolved by combining the novel shadowing effect of the deep trench with the surface-passivation effect of the SiO2 coating. Due to the robust connection and the absence of a contact barrier in bridging NWs, the intrinsic sensing properties of the NW itself can be obtained. For the first time, the gas-sensing properties (e.g., NO2) of the bridging GaN NWs were studied. With the assistance of UV light, the detection limit was improved from 4.5 to 0.5 ppb at room temperature, and the corresponding response time was reduced from 518 to 18 s. This kind of sensor is promising for high sensitivity (detection of less than parts per billion), low power consumption (capable of room-temperature operation), high stability (variation in resistance of <0.8% during 240 days), and in situ monolithic integration.

Itraconazole-loaded micelles based on linear-dendritic poly (ethylene glycol)-b-poly (ε-caprolactone).

A copolymeric micelle formulation of itraconazole (ITR-M) was prepared using linear-dendritic monoallyloxy poly (ethylene glycol)-b-poly (ε-caprolactone) (APEG-PCL) as drug carrier materials. DL and EE values of ITR-M were 5.70 ± 0.12% and 91.30 ± 1.90%, respectively. The micelle formulation enhanced the ITR solubility up to 30.42 µg/mL. In vitro release of ITR from the ITR-M was mainly drug diffusion process followed by the copolymer's degradation. ITR-M showed similar anti-Candida albicans activity to that of crude ITR although its release of ITR was slow and continuous. The in vivo pharmacokinetic study demonstrated that the ITR-M could improve tissue distribution of ITR. In conclusion, APEG-PCL could be a potential carrier in the development of antifungal drug delivery system.

MPEG-PCL Copolymeric Micelles for Encapsulation of Azithromycin.

Macrolide antibiotics are lipophilic drugs with some limitations including low solubility, limited cellular permeation, patients discomfort, etc. With amphiphilic methoxy poly(ethylene glycol)-b-poly(ε-caprolactone) (MPEG-PCL) copolymer and azithromycin (AZT) as drug carrier and model drug, AZT-loaded micelles were prepared via thin-membrane hydration method in order to overcome these limitations. Encapsulation efficiency of AZT-loaded micelles was 94.40% with good storage stability for 28 days, and AZT's water solubility was enhanced to 944 µg/mL. Fourier transform infrared spectrum and x-ray diffraction analysis indicated that AZT was enveloped into the micelles in amorphous form due to its interaction with the copolymer. AZT's in vitro release from the AZT-loaded micelles demonstrated a slow and continuous behavior when compared with raw AZT. The release dynamics was accorded with Weibull equation, meaning that release amount of AZT lowered with time and was proportional to remaining amount of drug in the AZT-loaded micelles. Korsmeyer-Peppas fitting result suggested that drug release process was a classical Fickian diffusion-controlled manner. With Staphylococcus aureus as bacterial strain, antibacterial activity of the AZT-loaded micelles displayed was comparable with raw AZT. In conclusion, MPEG-PCL should be a promising carrier for macrolide antibiotic delivery in treatment of bacterial infections.