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Experimental studies assessed the removal efficiency and fine-size distribution of CPM coupled with compositional analysis across air pollution control device systems (APCDs) at an ultra-low emission (ULE) power plant. The findings indicated total CPM emissions were reduced to a minimum of 0.418 mg/m3 at the Wet Electrostatic Precipitator (WESP). The Wet Flue Gas Desulfurization (WFGD) showed the highest removal efficiency (98%) across all particle sizes, notably in the ultra-micron range. Selective Catalytic Reduction (SCR) demonstrated a mere 34% overall efficiency, with a negative removal rate in the ultra-fine particle range. The WESP effectively removed CPM only in sub-micron and ultra-micron sizes, but significantly increased water-soluble ions formation in ultra-fine spatially suspended CPM (CPMspa), leading to overall negative efficiency. Thus, the removal efficiency of the ultra-fine particle range was most affected among the three particle size ranges when the flue gas went through the APCDs. Major metal elements and water-soluble ions were more readily removed by APCDs due to their surface aggregation, while the removal of trace elements like Hg and Se was limited. Reducing SO42-/NH4+ formation in SCR, and optimizing WESP spray system operations based on flue gas components are essential steps in controlling CPM concentration in ULE power plants.
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Natural siderite (FeCO3), simulated synthetic siderite and nZVI/FeCO3 composite were used as green and easily available iron-based catalysts in peroxydisulfate activation for remediating 2-chlorophenol as the target contaminant and this technique can effectively degrade organic pollutants in the soil. The key reaction parameters such as catalysts dosage, oxidant concentration and pH, were investigated to evaluate the catalytic performance of different materials in catalytic systems. The buffering property of natural soil conduced satisfactory degradation performance in a wide pH range (3-10). Both the main non-radical of 1O2 and free radicals of SO4·- and OH· were evidenced by quenching experiment and electron paramagnetic resonance. The reduction of nZVI on FFC surface not only has the advantage for electronic transfer to promote the circulation of Fe(III) to Fe(II), but also can directly dechlorinate. Furthermore, the intermediates were comprehensively analyzed by GC-MS and a potential removal mechanism of three oxidant system for 2-CP soil degradation was obtained. Briefly, this research provides a new perspective for organic contaminate soil treatment using natural siderite or simulated synthetic siderite as efficient and environmental catalytic material.
Assuntos
Compostos Férricos , Poluentes Químicos da Água , Compostos Férricos/química , Solo , Carbonatos/química , Oxirredução , Oxidantes , Poluentes Químicos da Água/análiseRESUMO
Deep-ultraviolet (DUV) solar-blind communication (SBC) shows distinct advantages of non-line-of-sight propagation and background noise negligibility over conventional visible-light communication. AlGaN-based DUV micro-light-emitting diodes (µ-LEDs) are an excellent candidate for a DUV-SBC light source due to their small size, low power consumption, and high modulation bandwidth. A long-haul DUV-SBC system requires the light source exhibiting high output power, high modulation bandwidth, and high rate, simultaneously. Such a device is rarely reported. A parallel-arrayed planar (PAP) approach is here proposed to satisfy those requirements. By reducing the dimensions of the active emission mesa to micrometer scale, DUV µ-LEDs with ultrahigh power density are created due to their homogeneous injection current and enhanced planar isotropic light emission. Interconnected PAP µ-LEDs with a diameter of 25 µm are produced. This device has an output power of 83.5 mW with a density of 405 W cm-2 at 230 mA, a wall-plug efficiency (WPE) of 4.7% at 155 mA, and a high -3 dB modulation bandwidth of 380 MHz. The remarkable high output power and efficiency make those devices a reliable platform to develop high-modulation-bandwidth wireless communication and to meet the requirements for bio-elimination.
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BACKGROUND: We aimed to investigate the analgesic effect and immune function of elderly patients with colon cancer after application of sevoflurane and isoflurane anesthesia. METHODS: Overall, 130 patients with colon cancer in Yidu Central Hospital of Weifang (Weifang, China) from February 2014 to January 2017 were collected and randomly divided into sevoflurane group (SEV group) and isoflurane group (ISO group). The pain score, immune indexes, postoperative cognitive index, extubation time, awakening time and S100R protein were analyzed. RESULTS: The pain scores in SEV group at 5 min, 1 h and 3 h during surgery were significantly lower than those in ISO group (P=0.001, respectively). The levels of IL-6 in both groups of patients were higher at T1 and T2 than those at T0 (P=0.001). The levels of TNF-α in SEV group at T2 and T3 were significantly higher than that at T0 (P=0.001). The levels of CD80 in both groups of patients at T2 and T3 were obviously higher than those at T0 (P=0.001). Moreover, the extubation time, the response time to language and awakening time in SEV group were also remarkably shorter than those in ISO group (P=0.001). After continuous anesthesia in both groups of patients, the degrees of decline in ISO group were significantly higher than those in SEV group (P=0.001). CONCLUSION: Sevoflurane has a superior anesthetic effect to isoflurane in elderly patients with colon cancer, can reduce the degree of pain, improve the awakening condition and increase the immune function, so it is worthy of clinical application.
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OBJECTIVE: To examine the role of KSOP1009 (a modified formulation of Suhexiang Wan essential oil) in an animal model of Parkinson's disease (PD) induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) injection. METHODS: Cell toxicity, apoptosis, and reactive oxygen species (ROS) levels were analyzed in the human neuroblastoma cell line SH-SY5Y. After that, changes in animal behavior and tyrosine hydroxylase (TH) protein levels in the substantia nigra (SN) of MPTP-injected mice were examined. Three different doses of KSOP1009 (30, 100, and 300 mg/kg, n = 8 for each group) were administered daily for 7 d before MPTP injection and 14 d after MPTP injection, totaling 21 d. RESULTS: MPP+, the active metabolite of MPTP, decreased the viability of SH-SY5Y cells, whereas KSOP1009 alleviated MPP+-induced cytotoxicity. KSOP1009 (10 and 50 mg/mL) reduced MPP+-induced ROS generation compared with the control group. Treatment with 1 mM MPP+ increased the percentage of depolarized/live cells, whereas KSOP1009 intake at a dose of 10 mg/mL decreased the percentage of these cells. The mean latency to fall in the rotarod test was reduced in mice treated with MPTP compared with the control group. However, mice receiving three different doses of KSOP1009 performed better than MPTP-treated animals. MPTP-treated mice were more hesitant and took longer to traverse the balance beam than the control animals. In contrast, KSOP1009-treated mice performed significantly better than MPTP- treated mice. Furthermore, the KSOP1009-treated groups had a significantly higher number of TH-positive neurons in the lesioned SN and significantly higher expression of TH in the striatum than the MPTP-treated group. MPTP treatment strongly induced Jun-N-terminal kinase (JNK) activation, whereas KSOP1009 suppressed MPTP-induced JNK activation. In addition, KSOP1009 intake reversed the decrease in the phosphorylation levels of cAMP-response element-binding protein in the brain of MPTP-treated mice. KSOP1009 also restored the decrease in dopaminergic neurons and dopamine levels in the brain of MPTP-treated mice. CONCLUSION: KSOP1009 protected mice against MPTP-induced toxicity by decreasing ROS formation and restoring mitochondrial function.
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Encéfalo/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Animais , Western Blotting , Encéfalo/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos ICR , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Fármacos Neuroprotetores/metabolismo , Doença de Parkinson/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismoRESUMO
Shikimate pathway plays an essential role in the biosynthesis of aromatic amino acids in various plants and bacteria, which consists of seven key enzymes and they are all attractive targets for antibacterial agent development due to their absence in humans. The Staphylococcus aureus dehydroquinate synthase (SaDHQS) is involved in the second step of shikimate pathway, which catalyzes the NAD + -dependent conversion of 3-deoxy-D-arabino-heptulosonate-7-phosphate to dehydroquinate via multiple steps. The enzyme active site can be characterized by two spatially separated subpockets 1 and 2, which represent the reaction center of substrate adduct with NAD + nicotinamide moiety and the assistant binding site of NAD + adenine moiety, respectively. In silico virtual screening is performed against a biogenic compound library to discover SaDHQS subpocket-specific inhibitors, which were then tested against both antibiotic-sensitive and antibiotic-resistant S. aureus strains by using in vitro susceptibility test. The activity profile of hit compounds has no considerable difference between the antibiotic-sensitive and -resistant strains. The subpocket 1-specific inhibitors exhibit a generally higher activity than subpocket 2-specific inhibitors, and they also hold a strong selectivity between their cognate and noncognate subpockets. Dynamics and energetics analyses reveal that the SaDHQS active site prefers to interact with amphipathic and polar inhibitors by forming multiple hydrogen bonds and van der Waals packing at the complex interfaces of the two subpockets with their cognate inhibitors.
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Antibacterianos/farmacologia , Proteínas de Bactérias/química , Farmacorresistência Bacteriana/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Fósforo-Oxigênio Liases/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Domínio Catalítico , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/química , Ensaios de Triagem em Larga Escala/métodos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , NAD/metabolismo , Fósforo-Oxigênio Liases/antagonistas & inibidores , Fósforo-Oxigênio Liases/metabolismoRESUMO
Brain-computer interfaces (BCIs) largely augment human capabilities by translating brain wave signals into feasible commands to operate external devices. However, many issues face the development of BCIs such as the low classification accuracy of brain signals and the tedious human-learning procedures. To solve these problems, we propose to use signals associated with eye saccades and blinks to control a BCI interface. By extracting existing physiological eye signals, the user does not need to adapt his/her brain waves to the device. Furthermore, using saccade signals to control an external device frees the limbs to perform other tasks. In this research, we use two electrodes placed on top of the left and right ears of thirteen participants. Then we use Independent Component Analysis (ICA) to extract meaningful EEG signals associated with eye movements. A sliding-window technique was implemented to collect relevant features. Finally, we classified the features as horizontal or blink eye movements using KNN and SVM. We were able to achieve a mean classification accuracy of about 97%. The two electrodes were then integrated with off-the-shelf earbuds to control a wheelchair. The earbuds can generate voice cues to indicate when to rotate the eyeballs to certain locations (i.e., left or right) or blink, so that the user can select directional commands to drive the wheelchair. In addition, through properly designing the contents of voice menus, we can generate as many commands as possible, even though we only have limited numbers of states of the identified eye saccade movements.