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Neural network pruning is a popular approach to reducing the computational complexity of deep neural networks. In recent years, as growing evidence shows that conventional network pruning methods employ inappropriate proxy metrics, and as new types of hardware become increasingly available, hardware-aware network pruning that incorporates hardware characteristics in the loop of network pruning has gained growing attention. Both network accuracy and hardware efficiency (latency, memory consumption, etc.) are critical objectives to the success of network pruning, but the conflict between the multiple objectives makes it impossible to find a single optimal solution. Previous studies mostly convert the hardware-aware network pruning to optimization problems with a single objective. In this paper, we propose to solve the hardware-aware network pruning problem with Multi-Objective Evolutionary Algorithms (MOEAs). Specifically, we formulate the problem as a multi-objective optimization problem, and propose a novel memetic MOEA, namely HAMP, that combines an efficient portfoliobased selection and a surrogate-assisted local search, to solve it. Empirical studies demonstrate the potential of MOEAs in providing simultaneously a set of alternative solutions and the superiority of HAMP compared to the state-of-the-art hardware-aware network pruning method. [ABSTRACT FROM AUTHOR]

This study investigates and compares the virucidal performances of photocatalytic (PC) and photoelectrocatalytic (PEC) treatments in the presence and absence of halides, such as Br- and Cl-, under comparable experimental conditions. The results confirm that the PC virucidal efficiency can be enhanced in the presence of low halide concentrations (e.g., X = Br- or Cl-) and further enhanced by applying potential bias onto the photoanode in a PEC system. The PEC treatment in the presence of 1.0 mM Br (PEC-Br) shows the highest virucidal efficiency, enabling complete inactivation of a ~1000 TCID50 replication-deficient recombinant adenovirus (RDRADS) population within 31.7 s. The superior virucidal performances of PEC-X treatments can be attributed to the increased production of active oxygen species and additional viricides resulting from the PEC halide oxidation, as well as prolonged lifetime of photoholes (h+) for direct inactivation. The findings of this work confirm that new forms of active species generated in situ via a PC or PEC process are effective for viruses. [ABSTRACT FROM AUTHOR]

A systematic approach was developed to understand, in-depth, the mechanisms involved during the inactivation of bacterial cells using photoelectrocatalytic (PEC) processes with Escherichia coli K-12 as the model microorganism. The bacterial cells were found to be inactivated and decomposed primarily due to attack from photogenerated H2O2. Extracellular reactive oxygen species (ROSs), such as H2O2ν may penetrate into the bacterial cell and cause dramatically elevated intracellular ROSs levels, which would overwhelm the antioxidative capacity of bacterial protective enzymes such as superoxide dismutase and catalase. The activities of these two enzymes were found to decrease due to the ROSs attacks during PEC inactivation. Bacterial cell wall damage was then observed, including loss of cell membrane integrity and increased permeability, followed by the decomposition of cell envelope (demonstrated by scanning electronic microscope images). One of the bacterial building blocks, protein, was found to be oxidatively damaged due to the ROSs attacks, as well. Leakage of cytoplasm and biomolecules (bacterial building blocks such as proteins and nucleic acids) were evident during prolonged PEC inactivation process. The leaked cytoplasmic substances and cell debris could be further degraded and, ultimately, mineralized with prolonged PEC treatment. [ABSTRACT FROM AUTHOR]

The objective of this work was to prepare novel magnetic Fe3O4/polyurethane foam (Fe3O4/PUF) composites applied to the carriers of immobilized microorganisms for toluene-containing wastewater treatment. The morphology and structure of Fe3O4/PUF composite were characterized by X-ray diffraction, Fourier transform IR spectroscopy, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy, and magnetic property measurement system. These morphological investigations revealed that Fe3O4 nano-particles were well dispersed into the matrix of PUF with nano-scale diameter particles. TG experiments indicated that the initial thermal weight loss temperatures of composite with the content of 2.5 wt% and 7.5% Fe3O4 were increased by 7 and 16 °C, compared with pure PUF. The degradation efficiency of toluene with magnetic PUF composite was much higher than that of pure PUF carrier, and the reason why the immobilization of microbial biomass of microorganisms on the magnetic PUF composite was much higher than that of the pure PUF. The prepared magnetic Fe3O4/PUF composite offered excellent thermal stability and medium paramagnetic properties. And this composite could not only increase the immobilized biomass of the microorganisms, but also enhance the COD removal efficiency of wastewater. [ABSTRACT FROM AUTHOR]

A new environment friendly adsorbent, cross-linked starch sulfate (CSS), was prepared and used to adsorb aniline from aqueous solution. Different adsorption parameters like initial pH, adsorption time, equilibrium aniline concentration, and temperature were thoroughly studied, and the kinetic, equilibrium, and thermodynamics of the adsorption process were further investigated. It showed that CSS can effectively remove aniline from the solution. The adsorption capacity is highly dependent on the amount of sulfate groups on adsorbents and the initial pH. The pseudo-first-order and pseudo-second-order kinetic models were applied to test the experimental data, and the pseudo-second-order kinetic model provided a better correlation of the experimental data in comparison with the pseudo-first-order model. The maximum removal efficiency of aniline is 75.29% using 1 g L−1of CSS3 dose. Langmuir, Freundlich, Dubinin−Radushkevich, and Sips models have been applied to study the adsorption equilibrium, and the equilibrium adsorption data were well described by the Sips isotherms. The Scatchard plot analysis was used to evaluate the binding sites of CSS. The adsorption of aniline on CSS is exothermic in nature. [ABSTRACT FROM AUTHOR]

Oilfield produced water was treated by photocatalysis, electro-oxidation, and photoelectrocatalysis, respectively. The chemical composition and toxicity of the raw effluent and treated products were assessed by chemical and mutagenicity analysis. The raw effluent exhibited mutagenic activity in both strains of Salmonella typhimurium. The lowest concentration of the dichloromethane extract capable of inducing a positive response in strains TA98 and TA100 were as low as 4 and 5 μg/plate, respectively. All three technologies could detoxify direct-acting mutagenic organic pollutants efficiently, although they could not completely eliminate mutagenicity in the water after 60 min of treatment. At equivalent doses, photoelectrocatalysis exhibited the greatest capability to reduce genotoxicity, whereas photocatalysis was the least effective and did not cause appreciable change in mutagenicity. The gas chromatography-mass spectrometry (GC-MS) analysis revealed that n-alkanes (259.4 ng/L) and phenolic compounds (2,501.4 ng/L) were the main organic constituents in the oilfield produced water. Thus, the results of both biological and chemical analysis indicate that photoelectocatalysis was the most effective technology for degradation of oilfield wastewater. [ABSTRACT FROM AUTHOR]

Disinfection technologies, especially light-based disinfection, have undergone tremendous development and innovation, but this treatment can cause bacteria to enter viable but nonculturable (VBNC) state. Due to their strong tolerance, VBNC bacteria cannot be completely removed by disinfection technologies, thereby posing a potential risk for antibiotic resistance gene (ARG) transfer. Therefore, to better understand VBNC bacteria and interpret potential transfer of ARGs, this article systematically reviewed changes in morphology, physiology and virulence of bacteria after entering VBNC state. In addition, this article reviewed quantitative detection methods of VBNC bacteria, such as cell membrane integrity-mediated LIVE/DEAD Baclight assay, qPCR-based assays, and phage-based detection methods, concluding that there is still a lack of in-situ and real-time detection methods for VBNC bacteria. Health risks and environmental application value of VBNC bacteria were then valuated, with data indicating that VBNC bacteria have great value in the domain of microbial utilization. Furthermore, the induction conditions (especially by light-based disinfection) and formation mechanisms of VBNC bacteria were highlighted. Formation mechanisms mainly involve stringent response, general stress response system and toxin-antitoxin (TA) system. Moreover, horizontal gene transfer (HGT) of ARGs during and after the formation of VBNC bacteria induced by light-based disinfection was evaluated. It was found that ARGs may be transferred through conjugation, transformation and transduction. Finally, current deficiencies and future challenges for the transformation of VBNC bacteria, especially those influenced by light-based disinfection technologies, were summarized. This review provides new insights into detection methods, formation mechanisms, environmental applications and potential ARG transfer risks of VBNC bacteria. [ABSTRACT FROM AUTHOR]

The aerosol transmission of coronavirus disease in 2019, along with the spread of other respiratory diseases, caused significant loss of life and property; it impressed upon us the importance of real-time bioaerosol detection. The complexity, diversity, and large spatiotemporal variability of bioaerosols and their external/internal mixing with abiotic components pose challenges for effective online bioaerosol monitoring. Traditional methods focus on directly capturing bioaerosols before subsequent time-consuming laboratory analysis such as culture-based methods, preventing the high-resolution time-based characteristics necessary for an online approach. Through a comprehensive literature assessment, this review highlights and discusses the most commonly used real-time bioaerosol monitoring techniques and the associated commercially available monitors. Methods applied in online bioaerosol monitoring, including adenosine triphosphate bioluminescence, laser/light-induced fluorescence spectroscopy, Raman spectroscopy, and bioaerosol mass spectrometry are summarized. The working principles, characteristics, sensitivities, and efficiencies of these real-time detection methods are compared to understand their responses to known particle types and to contrast their differences. Approaches developed to analyze the substantial data sets obtained by these instruments and to overcome the limitations of current real-time bioaerosol monitoring technologies are also introduced. Finally, an outlook is proposed for future instrumentation indicating a need for highly revolutionized bioaerosol detection technologies. [ABSTRACT FROM AUTHOR]

Background: The combined treatment of transcatheter arterial chemoembolization (TACE) and apatinib had beneficial effects on the survival of patients with advanced hepatocellular carcinoma (HCC), but the efficacy of this regimen is still controversial and needs further investigation. Materials and Methods: The clinical records of advanced HCC patients between May 2015 and December 2016 were collected from our hospital. They were categorized into the TACE monotherapy group and the combination of TACE and apatinib group. After propensity score matching (PSM) analysis, the disease control rate (DCR), objective response rate (ORR), progression-free survival (PFS), and occurrence of adverse events were compared between the two treatments. Results: There were 115 HCC patients included in the study. Among them, 53 received TACE monotherapy and 62 were treated with TACE plus apatinib. After PSM analysis, 50 pairs of patients were compared. The DCR of the TACE group was significantly lower than that of the combination of TACE and apatinib group (35 [70%] versus 45 [90%], P < 0.05). The ORR of the TACE group was also significantly lower than that of the combination of TACE and apatinib group (22 [44%] versus 34 [68%], P < 0.05). Patients who received the combined treatment of TACE and apatinib had longer PFS compared with those in the TACE monotherapy group (P < 0.001). Moreover, hypertension, hand–foot syndrome, and albuminuria were more common in the combination of TACE and apatinib group (P < 0.05), although all adverse events were well tolerated. Conclusions: The combined treatment of TACE and apatinib showed beneficial effects on tumor response, survival outcomes, and tolerance to treatment, which may be used as a routine regimen for advanced HCC patients. [ABSTRACT FROM AUTHOR]

Recycling e-waste is increasingly recognized as an important resource management strategy; however, the process emits different pollutants, including volatile organic compounds (VOCs). Sixteen dominant VOCs, with total concentrations ranging from 1.6 x 10³ to 6.7 x 10³ μg m-3, were presented during the manual process of dismantling television printed circuit boards using electric heating furnaces. An integrated treatment technique, involving a spray tower (ST), electrostatic precipitation (EP), and photocatalysis (PC), was used to eliminate these VOCs. The highest VOC removal efficiency during the 60-day treatment period was 69.5%. The removal efficiency was mainly due to the combined effect of preferential elimination of hydrosoluble VOCs and efficient interception of large-sized particles by ST; the enhanced capture efficiency of micro-sized particles by EP; and the dominant degradation of particle-free VOCs by PC. The PC treatment was able to remove more hydrocarbons (an average 62.7%) than nitrogen- and oxygen-containing and aromatic compounds (36.4% and 27.3% in average), due to the hydrocarbons' higher dielectric constants. Risk assessment revealed that the non-cancer and cancer risks associated with VOCs significantly decreased after the integrated technique was applied, indicating that the treatment is an efficient approach for purifying the atmosphere and protecting human health inside e-waste recycling workshops. [ABSTRACT FROM AUTHOR]

RuO2-PdO/Ti electrode was prepared and used for the electro-catalytic degradation of Active Red K-2BP. It was found that the electrode was very stable in the process. A discoloration rate of 96.2% could still be achieved on the electrode after being used for 100 runs. X-ray photoelectron spectroscopy, X-ray diffraction, and scanning electron microscopy characterizations of the electrode were carried out. Results showed that the deactivation of the electrode was caused by the reconstruction and oxidation of titanium substrate as well as by the coverage of the active phases on the surface of the electrode by silicon. The cracks on the coating layer also contributed to the deactivation. [ABSTRACT FROM AUTHOR]

The hydroxyl radical (•OH) is one of the main oxidative species in aqueous phase advanced oxidation processes, and its initial reactions with organic pollutants are important to understand the transformation and fate of organics in water environments. Insights into the kinetics and mechanism of •OH mediated degradation of the model environmental endocrine disruptor, dimethyl phthalate (DMP), have been obtained using radiolysis experiments and computational methods. The bimolecular rate constant for the •OH reaction with DMP was determined to be (3.2 ± 0.1) × 109 M−1s−1. The possible reaction mechanisms of radical adduct formation (RAF), hydrogen atom transfer (HAT), and single electron transfer (SET) were considered. By comparing the experimental absorption spectra with the computational results, it was concluded that the RAF and HAT were the dominant reaction pathways, and OH-adducts (•DMPOH1, •DMPOH2) and methyl type radicals •DMP(-H)α were identified as dominated intermediates. Computational results confirmed the identification of transient species with maximum absorption around 260 nm as •DMPOH1 and •DMP(-H)α, and these radical intermediates then converted to monohydroxylated dimethyl phthalates and monomethyl phthalates. Experimental and computational analyses which elucidated the mechanism of •OH-mediated degradation of DMP are discussed in detail. [ABSTRACT FROM AUTHOR]

The absolute kinetic rate constants of propylparaben (PPB) in water with different free radicals were investigated, and it was found that both hydroxyl radicals (HO•) and hydrated electrons could rapidly react with PPB. The advanced oxidation kinetics and mechanisms of PPB were investigated using photocatalytic process as a model technology, and the degradation was found to be a pseudo-first-order model. Oxidative species, particularly HO•, were the most important reactive oxygen species mediating photocatalytic degradation of PPB, and PPB degradation was found to be significantly affected by pH because it was controlled by the radical reaction mechanism and was postulated to occur primarily via HO•-addition or H-abstraction reactions on the basis of pulse radiolysis measurements and observed reaction products. To investigate potential risk of PPB to humans and aqueous organisms, the estrogenic assays and bioassays were performed using 100 μM PPB solution degraded by photocatalysis at specific intervals. The estrogenic activity decreased as PPB was degraded, while the acute toxicity at three trophic levels first increased slowly and then decreased rapidly as the total organic carbon decreased during photocatalytic degradation. [ABSTRACT FROM AUTHOR]

TiO2 pillared montmorillonites were prepared by introducing Ti4+ into a layer of montmorillonite modified with or without cetyltrimethylammonium bromide. The components and texture of the prepared composites were characterized by thermogravimetric analysis, X-ray powder diffraction and scanning electron microscopy. The adsorption and photocatalytic degradation performance of a model environmental endocrine disruptor, dimethyl phthalate ester, were investigated using this newly prepared hydrophobic TiO2 pillared montmorillonite photocatalyst. The adsorption of dimethyl phthalate ester from water varied from 9% to 28% on the prepared hydrophobic photocatalyst. Although the experimental results showed that the photocatalytic activity of the hydrophobic photocatalyst was slightly lower than that of hydrophilic one, electron spin resonance verified that hydroxyl radicals were also generated in hydrophobic TiO2 pillared montmorillonite photocatalyst under UV irradiation. To elucidate the decomposition mechanism of dimethyl phthalate ester, 12 main photocatalytic intermediates were identified during the photocatalytic degradation process, and a plausible degradation mechanism was also proposed. [ABSTRACT FROM AUTHOR]

Secondary organic aerosol (SOA) represents a major constituent of tropospheric fine particulate matter, with profound implications for human health and climate. However, the chemical mechanisms leading to SOA formation remain uncertain, and atmospheric models consistently underpredict the global SOA budget. Small α-dicarbonyls, such as methylglyoxal, are ubiquitous in the atmosphere because of their significant production from photooxidation of aromatic hydrocarbons from traffic and industrial sources as well as from biogenic isoprene. Current experimental and theoretical results on the roles of methylglyoxal in SOA formation are conflicting. Using quantum chemical calculations, we show cationic oligomerization of methylglyoxal in aqueous media. Initial protonation and hydration of methylglyoxal lead to formation of diols/tetrol, and subsequent protonation and dehydration of diols/tetrol yield carbenium ions, which represent the key intermediates for formation and propagation of oligomerization. On the other hand, our results reveal that the previously proposed oligomerization via hydration for methylglyoxal is kinetically and thermodynamically implausible. The carbenium ion-mediated mechanism occurs barrierlessly on weakly acidic aerosols and cloud/fog droplets and likely provides a key pathway for SOA formation from biogenic and anthropogenic emissions. [ABSTRACT FROM AUTHOR]

Objective: To study and compare the clinical effects of azithromycin and erythromycin on children with mycoplasma pneumonia. Methods: Total 132 children with mycoplasma pneumonia who were admitted to our hospital between November 2017 and September 2018 were selected as the research subjects. All the children were divided into an observation group and a control group according to random number table, 66 each. The observation group was treated with azithromycin, while the control group was treated with erythromycin. The therapeutic effect, incidence of adverse reactions and disappearance time of clinical symptoms were compared between the two groups. Results: The total efficacy of the observation group was 98.04%, and that of the control group was 74.51%; there was a significant difference (X²=7.184, P=0.007). The incidence of adverse reactions in the observation group was 15.69%, significantly lower than that in the control group (41.18%) (X²=6.376, P=0.002). The disappearance of fever, cough, rale and X ray shadow of the observation group was significantly earlier than that of the control group, and the difference was statistically significant (P<0.05). Conclusion: Compared with erythromycin, azithromycin is more effective in the treatment of mycoplasma pneumonia in children. Azithromycin can further shorten the improvement time of clinical symptoms and signs and has few adverse reactions and high safety. It is worth clinical application. [ABSTRACT FROM AUTHOR]

Cross-linked amino-starch (CAS) was prepared via a dry process and used to adsorb glyphosate from aqueous solution. Effects of adsorption time, glyphosate concentration, temperature, pH, and ionic strength on the adsorption of glyphosate by CAS were thoroughly studied. It shows that CAS can effectively remove glyphosate from the solution. The adsorption equilibrium is attained in about 60 min, and the adsorption process follows the pseudo second-order kinetic model. Sips isotherm model is more suitable than Langmuir and Freundlich isotherm models for the adsorption process, and the maximum adsorption capacity is 3.61 mmol·g-1 from Sips isotherm fitting. The result of thermodynamics study indicates that the adsorption is a spontaneous and exothermic process. The results of isotherm and thermodynamics study show that the adsorption of glyphosate by CAS is attributed to a combination of chemical and physical processes. The adsorption process is severely affected by pH and ionic strength of the solution and the optimal adsorption performance is achieved at pH = 6.0. [ABSTRACT FROM AUTHOR]

Cyclin D1 has become a potential target for anti-tumor therapy. Recently, a novel human anti-cyclin D1 single-chain variable fragment (AD5) was identified, which demonstrated specific binding activity to cyclin D1 and exhibited anti-tumor effects. However, the detailed characteristics of AD5 remain unclear. In the present study, the structure and activity of AD5 in the presence of copper II (Cu2+) or iron III (Fe3+) metal ions was investigated by fluorescence spectroscopy, synchronous fluorescence and enzyme-linked immunosorbent assay. Cu2+ and Fe3+ were able to bind to AD5 and quench the fluorescence intensity of AD5 primarily by static quenching, which slightly altered the conformation of AD5 at temperatures of 293, 298 and 303 K; however, these temperatures demonstrated different effects on the activity of AD5. These results may be of value for the clinical application of anti-cyclin D1 single chain antibodies in the future. [ABSTRACT FROM AUTHOR]

Previous studies have shown that Lycium barbarum polysaccharides (LBPs) serve an important role in antioxidant activity to protect the cells and tissues. However, the specific mechanism of LBPs in the prevention of endometrial damage remains to be elucidated. Using morphological observation, cell proliferation assay, the detection of superoxide dismutase (SOD) activity and the content of malondialdehyde (MDA) in cell culture supernatant fluid, the detection by western blot analysis and reverse transcription-quantitative polymerase chain reaction of the mRNA and protein expression levels of caspase-3 and Bcl-2 in endometrial stromal cells (ESCs), it was demonstrated that, in vitro, hydrogen peroxide (H2O2)-induced death of ESCs, increased the content of MDA and decreased the activity of SOD, and decreased the expression of Bcl-2 and increased the expression of caspase-3. LBPs can inhibit H2O2-induced cell death of ESCs, decrease the content of MDA in ESCs and increase the activity of SOD, as well as increasing the expression of Bcl-2 and decreasing the expression levels of caspase-3. These findings suggested that LBPs can inhibit H2O2-induced apoptosis of EECs and that LBPs are able to offer a significant protection against oxidative stress to ESCs. [ABSTRACT FROM AUTHOR]

Bartter syndrome (BS) type 1 is an autosomal recessive kidney disorder caused by loss-of-function mutations in the solute carrier family 12 member 1 (SLC12A1) gene. To date, 72 BS type 1 patients harboring SLC12A1 mutations have been documented. Of these 144 alleles studied, 68 different disease-causing mutations have been detected in 129 alleles, and no mutation was detected in the remaining 15 alleles. The mutation types included missense/nonsense mutations, splicing mutations and small insertions and deletions ranging from 1 to 4 nucleotides. A large deletion encompassing a whole exon in the SLC12A1 gene has not yet been reported. The current study initially identified an undocumented homozygous frameshift mutation (c.1833delT) by Sanger sequencing analysis of a single infant with BS type 1. However, in a subsequent analysis, the mutation was detected only in the father's DNA. Upon further investigation using a next-generation sequencing approach, a deletion in exons 14 and 15 in both the patient and patient's mother was detected. The deletion was subsequently confirmed by use of a long-range polymerase chain reaction and was determined to be 3.16 kb in size based on sequencing of the junction fragment. The results of the present study demonstrated that pathogenic variants of SLC12A1 are heterogeneous. Large deletions appear to serve an etiological role in BS type 1, and may be more prevalent than previously thought. [ABSTRACT FROM AUTHOR]

The treatment of dye wastewater by activated carbon (AC) prepared from rice husk residue wastes was studied. Batch adsorption studies were conducted to investigate the effects of contact time, initial concentration (50–450 mg/L), pH (3–11) and temperature (30–70 °C) on the removal of methylene blue (MB), neutral red, and methyl orange. Kinetic investigation revealed that the adsorption of dyes followed pseudo-second-order kinetics. The results suggested that AC was effective to remove dyes, especially MB, from aqueous solutions. Desorption studies found that chemisorption by the adsorbent might be the major mode of dye removal. Fourier transform infrared results suggested that dye molecules were likely to combine with the O–H and P=OOH groups of AC. [ABSTRACT FROM AUTHOR]

The dual roles of capsular extracellular polymeric substances (EPS) in the photocatalytic inactivation of bacteria were demonstrated in a TiO2-UVA system, by comparing wild-type Escherichia coli strain BW25113 and isogenic mutants with upregulated and downregulated production of capsular EPS. In a partition system in which direct contact between bacterial cells and TiO2 particles was inhibited, an increase in the amount of EPS was associated with increased bacterial resistance to photocatalytic inactivation. In contrast, when bacterial cells were in direct contact with TiO2 particles, an increase in the amount of capsular EPS decreased cell viability during photocatalytic treatment. Taken together, these results suggest that although capsular EPS can protect bacterial cells by consuming photogenerated reactive species, it also facilitates photocatalytic inactivation of bacteria by promoting the adhesion of TiO2 particles to the cell surface. Fluorescence microscopy and scanning electron microscopy analyses further confirmed that high capsular EPS density led to more TiO2 particles attaching to cells and forming bacterium-TiO2 aggregates. Calculations of interaction energy, represented by extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) potential, suggested that the presence of capsular EPS enhances the attachment of TiO2 particles to bacterial cells via acid-base interactions. Consideration of these mechanisms is critical for understanding bacterium-nanoparticle interactions and the photocatalytic inactivation of bacteria. [ABSTRACT FROM AUTHOR]

Hydroxyl radicals (·OH) are strong oxidants that can degrade organic pollutants in advanced oxidation processes (AOPs). The mechanisms, kinetics, and toxicity assessment of the ·OH-initiated oxidative degradation of the phenolic preservative, methylparaben (MPB), were systematically investigated using a computational approach, as the supplementary information for experimental data. Results showed that MPB can be initially attacked by ·OH via OH-addition and H-abstraction routes. Among these routes, the ·OH addition to the C atom at the ortho-position of phenolic hydroxyl group was the most significant route. However, the methyl-H-abstraction route also cannot be neglected. Further, the formed transient intermediates, OH-adduct (·MPB-OH1) and dehydrogenated radical (·MPB(-H)α), could be easily transformed to several stable degradation products in the presence of O2 and ·OH. To better understand the potential toxicity of MPB and its products to aquatic organisms, both acute and chronic toxicities were assessed computationally at three trophic levels. Both MPB and its products, particularly the OH-addition products, are harmful to aquatic organisms. Therefore, the application of AOPs to remove MPB should be carefully performed for safe water treatment. [ABSTRACT FROM AUTHOR]

Intrauterine adhesions (IUA) may be caused by endometrial stromal cell proliferation, increases in myofibroblasts or increases in extracellular matrix secretion. However, the specific mechanisms underlying the development of IUA have yet to be elucidated. The present study identified that angiotensin (Ang) II is capable of promoting endometrial epithelium cell (EEC) proliferation and the transdifferentiation of EECs into myofibroblasts. Furthermore, the present study found that Ang II increased the expression of the myofibroblast specific protein α-smooth muscle actin (α-SMA), decreased the expression and secretion of E-cadherin, and increased the synthesis of collagen type I (Col I) and fibronectin (FN). However, Ang-(l-7) was observed to inhibit Ang Il-induced proliferation and transdifferentiation of EECs, decrease the expression of α-SMA, increase the expression of E-cadherin and decrease the synthesis and secretion of Col I and FN. These findings suggest that Ang-(l-7) is capable of inhibiting the Ang Il-induced proliferation and transdifferentiation of human EECs and decreases in Col I and FN secretion. The present study may provide insight into the mechanism underlying endometrial fibrosis. [ABSTRACT FROM AUTHOR]

Motivated by recent studies that well-documented mineral photocatalyst for bacterial inactivation, a novel natural magnetic sphalerite (NMS) in lead-zinc deposit was first discovered and evaluated for its visible-light-driven (VLD) photocatalytic bactericidal properties. Superior to the reference natural sphalerite (NS), vibrating sampling magnetometeric (VSM) analysis revealed the ferromagnetic property of NMS, indicating its potential for easy separation after use. Under the irradiation of fluorescence tubes, NMS could inactivate 7 log10 Gram-negative Escherichia coli K-12 without any regrowth and metal ions leached out from NMS show no toxicity to cells. The cell destruction process starting from cell wall to intracellular components was verified by TEM. Some products from damaged cells such as aldehydes, ketones and carboxylic acids were identified by FTIR with a decrease of cell wall functional groups. The relative amounts of potassium ion leakage from damaged cells gradually increased from initial 0 to approximately constant concentration of 1000 ppb with increasing reaction time. Superoxide radical (•O2 -) rather than hydroxyl radical (•OH) was proposed to be the primary reactive oxidative species (ROSs) responsible for E. coli inactivation by use of probes and electron spin resonance (ESR). H2O2 determined by fluorescence method is greatly involved in bacterial inactivation in both nonpartition and partition system. Multiple cycle runs revealed excellent stability of recycled NMS without any significant loss of activity. This study provides a promising natural magnetic photocatalyst for large-scale bacterial inactivation, as NMS is abundant, easily recycled and possessed an excellent VLD bacterial inactivation ability. [ABSTRACT FROM AUTHOR]

This study investigated the interaction between eupatorin and bovine serum albumin (BSA) using ultraviolet-visible (UV-vis) absorption, fluorescence, synchronous fluorescence, circular dichroism (CD) spectroscopies, and molecular modeling at pH 7.4. Results of UV-vis and fluorescence spectroscopies illustrated that BSA fluorescence was quenched by eupatorin via a static quenching mechanism. Thermodynamic parameters revealed that hydrophobic and electrostatic interactions played major roles in the interaction. Moreover, the efficiency of energy transfer, and the distance between BSA and acceptor eupatorin, were calculated. The effects of eupatorin on the BSA conformation were analyzed using UV-vis, CD, and synchronous fluorescence. Finally, the binding of eupatorin to BSA was modeled using the molecular docking method. [ABSTRACT FROM AUTHOR]

Diabetes is a common comorbidity in cystic fibrosis (CF) that worsens prognosis. The lack of an animal model for CF-related diabetes (CFRD) has made it difficult to dissect how the onset of pancreatic pathology influences the emergence of CFRD. We evaluated the structure and function of the neonatal CF endocrine pancreas using a new CFTR-knockout ferret model. Although CF kits are born with only mild exocrine pancreas disease, progressive exocrine and endocrine pancreatic loss during the first months of life was associated with pancreatic inflammation, spontaneous hyperglycemia, and glucose intolerance. Interestingly, prior to major exocrine pancreas disease, CF kits demonstrated significant abnormalities in blood glucose and insulin regulation, including diminished first-phase and accentuated peak insulin secretion in response to glucose, elevated peak glucose levels following glucose challenge, and variably elevated insulin and C-peptide levels in the nonfasted state. Although there was no difference in lobular insulin and glucagon expression between genotypes at birth, significant alterations in the frequencies of small and large islets were observed. Newborn cultured CF islets demonstrated dysregulated glucose-dependent insulin secretion in comparison to controls, suggesting intrinsic abnormalities in CF islets. These findings demonstrate that early abnormalities exist in the regulation of insulin secretion by the CF endocrine pancreas. [ABSTRACT FROM AUTHOR]

Bismuth vanadate nanotube (BV-NT), synthesized by a template-free solvothermal method, was used as an effective visible-light-driven (VLD) photocatalyst for inactivation of Escherichia coli K-12. The mechanism of photocatalytic bacterial inactivation was investigated by employing multiple scavengers combined with a simple partition system. The VLD photocatalytic bacterial inactivation by BV-NT did not allow any bacterial regrowth. The photogenerated h+ and reactive oxidative species derived from h+, such as •OHads, H2O2 and •HO2/•O2-, were the major reactive species for bacterial inactivation. The inactivation by h+ and •OHads required close contact between the BV-NT and bacterial cells, and only a limited amount of H2O2 could diffuse into the solution to inactivate bacterial cells. The direct oxidation effect of h+ to bacterial cells was confirmed by adopting F- surface modification and anaerobic experiments. The bacterial cells could trap e- in order to minimize e--h+ recombination, especially under anaerobic condition. Transmission electron microscopic study indicated the destruction process of bacterial cell began from the cell wall to other cellular components. The •OHads was postulated to be more important than •OHbulk and was not supposed to be released very easily in the BV-NT bacterial inactivation system. [ABSTRACT FROM AUTHOR]

The controversy of mechanism still exists over whether photocatalytic decontamination proceeds via photon-generated h+, e−, ꔷOH, ꔷO2− or H2O2. This study aims to investigate the roles of these reactive charges and oxidative species in the photocatalytic dye decolorization and bacterial disinfection processes in the presence of a visible-light-driven (VLD) photocatalyst, B–Ni-codoped TiO2 microsphere, by employing various scavengers in the photocatalytic system and utilizing a novel partition system. Significant differences between VLD photocatalytic dye decolorization and bacterial disinfection are found. For photocatalytic dye decolorization, the reaction mainly occurs on the photocatalyst surface with the aid of surface-bounded reactive species (h+, ꔷOHs and ꔷO2−), while bacterial cell can be inactivated by diffusing reactive oxidative species such as ꔷOHb and H2O2 without the direct contact with the photocatalyst. The diffusing H2O2 plays the most important role in the photocatalytic disinfection, which can be produced both by the coupling of ꔷOHb in bulk solution and ꔷOHs on the surface of photocatalyst at the valence band. Furthermore, the ꔷO2−, which is detected by using the electron spin resonance technique, is found to have direct function for the photocatalytic disinfection process. This study establishes a facile and versatile research methodology to investigate the VLD photocatalytic mechanism in different photocatalytic system. [ABSTRACT FROM AUTHOR]

To eliminate volatile organic compounds (VOCs) from contaminated air, a novel medium-scale baffled photocatalytic reactor was designed and fabricated, using immobilized ZnO/SnO2 coupled oxide photocatalysts. Toluene was chosen as a representative pollutant of VOCs to investigate the degradation mechanism and the parameters affecting photocatalytic degradation efficiency. The preliminary experimental results indicate that the degradation efficiency of toluene increased with the increase of the light irradiation dosage, while it decreased with the increase of concentrations of toluene. The degradation efficiency increased rapidly with the increase of the relative humidity in a low humidity range from 0 to 35%, but decreased gradually in a high relative humidity (i.e., >35%). The optimum experimental conditions for toluene degradation is a toluene concentration of 106 mg m−3, a relative humidity of 35%, and an illumination intensity of ca. 6 mW cm−2 at the surface of ZnO/SnO2 photocatalysts. The intermediates produced during the gaseous photocatalytic degradation process were identified using the GC–MS technique. Based on these identified intermediates, the photocatalytic mechanism of toluene into ZnO/SnO2 coupled oxide catalyst was also deduced. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) and carbon nanotubes (CNTs) are the two most popular functional materials in recent years. In this study, CNTs/TiO2 composite and TiO2 photoanodes were fabricated by a dip-coating technique, followed by subsequent calcination. The resultant photoanodes were characterized by scanning electron microscopy (SEM), x-ray diffraction (XRD), and UV-visible spectroscopy (UV-vis). The results suggest that the carbon nanotubes were successfully incorporated with the TiO2 nanoparticulates without damage and that the resultant TiO2 nanoparticles consisted of anatase and rutile. The CNTs/TiO2 photoanodes were capable of oxidizing various types of organic compounds (e.g. glucose, potassium hydrogen phthalate, and phenol) in aqueous solutions in a photoelectrochemical bulk cell. In comparison with the pure TiO2 photoanode, the sensitivity of the photoanode for the detection of organic compounds has been improved by 64%, while the background current was reduced by 80% due to the introduction of the CNTs. These advantages can be ascribed to the improved adsorptivity to organic compounds, increased absorption of UV light and enhanced electron transport at the CNTs/TiO2 photoanode due to the introduction of the CNTs. [ABSTRACT FROM AUTHOR]