The impact of benzoic acid and lactic acid on the treatment efficiency and microbial community in the sulfur autotrophic denitrification process.

Nitrate poses a potential threat to aquatic ecosystems. This study focuses on the sulfur autotrophic denitrification mechanism in the process of water culture wastewater treatment, which has been successfully applied to the degradation of nitrogen in water culture farm effluents. However, the coexistence of organic acids in the treatment process is a common environmental challenge, significantly affecting the activity of denitrifying bacteria. This paper aims to explore the effects of adding benzoic acid and lactic acid on denitrification performance, organic acid removal rate, and microbial population abundance in sulfur autotrophic denitrification systems under optimal operating conditions, sulfur deficiency, and high hydraulic load. In experiments with 50 mg·L-1 of benzoic acid or lactic acid alone, the results show that benzoic acid and lactic acid have a stimulating effect on denitrification activity, with the stimulating effect significantly greater than the inhibitory effect. Under optimal operating conditions, the average denitrification rate of the system remained above 99%; under S/N = 1.5 conditions, the average denitrification rate increased from 88.34% to 91.93% and 85.91%; under HRT = 6 h conditions, the average denitrification rate increased from 75.25% to 97.79% and 96.58%. In addition, the addition of organic acids led to a decrease in microbial population abundance. At the phylum level, Proteobacteria has always been the dominant bacterial genus, and its relative abundance significantly increased after the addition of benzoic acid, from 40.2% to 61.5% and 62.4%. At the genus level, Thiobacillus, Sulfurimonas, Chryseobacterium, and Thermomonas maintained high population abundances under different conditions. PRACTITIONER POINTS: Employing autotrophic denitrification process for treating high-nitrate wastewater. Utilizing organic acids as external carbon sources. Denitrifying bacteria demonstrate high utilization efficiency towards organic acids. Organic acids promote denitrification more than they inhibit it. The promotion is manifested in the enhancement of activity and microbial abundance.

Imaging and reconstruction of high-energy proton beam spot before target based on secondary gamma rays.

The distribution and stability of the incident proton beam spot are critical for the stable operation of a high-power spallation target. This study proposes a method to capture images of the incident proton beam spot based on secondary gamma rays. The distribution of the backward secondary gamma rays irradiated by the primary proton beam on the incident surface of the target is close to the distribution of the protons and can be measured at a low-radiation position far from the target area. A relation of distributions between the incident protons and the secondary gammas is constructed by using the point response function of this pinhole imaging system. The proposed method of imaging is suitable for monitoring the distribution of the proton beam on the target in facilities that use a beam power of several megawatts or tens of megawatts, such as spallation neutron sources or accelerator-driven subcritical systems.

Exploring the Potential Targets and Mechanisms of Huang Lian Jie Du Decoction in the Treatment of Coronavirus Disease 2019 Based on Network Pharmacology.

BACKGROUND: In December 2019, coronavirus disease 2019 (COVID-19) caused by a novel coronavirus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2; previously known as 2019-nCoV) emerged in Wuhan, China, and caused many infections and deaths. At present, there are no specific drugs for the etiology and treatment of COVID-19. A combination of traditional Chinese and western medicine is proposed to treat COVID-19, in which Huang Lian Jie Du decoction (HLJDD) is recommended for the treatment of COVID-19 in many provinces in China and has been widely used in the clinic. This study explored the potential targets of HLJDD in the treatment of COVID-19 based on network pharmacology. METHODS: First, the chemical composition and targets of HLJDD and COVID-19-related targets were obtained through the TCMSP, UniProt, GeneCards and OMIM databases. Second, HLJDD target and HLJDD-COVID-19 target networks were constructed via the STRING database and Cytoscape software. Finally, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of the HLJDD-COVID-19 targets was applied via the DAVID database. RESULTS: Our study identified a total of 67 active ingredients of HLJDD and 204 targets of HLJDD. A total of 502 COVID-19-related targets were obtained, of which 47 were intersecting targets of HLJDD and COVID-19. A total of 179 GO terms and 77 KEGG terms, including the TNF signaling pathway, NF-κB signaling pathway and HIF-1 signaling pathway, were identified. CONCLUSION: The present study explored the potential targets and signaling pathways of HLJDD during the treatment of COVID-19, which may provide a basis for the research and development of drugs for the treatment of COVID-19.

Feasibility of nuclide-identified imaging based on the back-streaming white neutron beam at the China Spallation Neutron Source.

Back-streaming neutrons through the incoming proton channel at the spallation target station of the China Spallation Neutron Source have been studied as a white neutron source (Back-n). We report a physical study on white neutron imaging based on the Back-n beamline. The wide neutron energy spectrum spanning from 1 eV to 100 MeV was very suitable for nuclide-identified imaging as well as measurements of nuclear data and other applications. We calculated the back-streaming white neutron energy spectrum using the Monte Carlo N-Particle code. A comparison of the results of calculation with those of the FLUktuierende KAskade code and experimental measurements were carried out. The energy resolution of the Back-n beam was close to 5% depending on the neutron energy and the modes of operation, and its spatial resolution could attain the order of tens of micrometers.

Iron-oxide-identifying imaging method based on a wide-energy neutron beam for corrosion inspection in reinforced concrete structures.

To prevent potential hazards caused by steel corrosion, there is an increase in demand for non-destructive inspection or monitoring of reinforcing steel corrosion in concrete structures. In this study, an iron-oxide-identifying imaging method is proposed that is based on a neutron resonance transmission imaging technique. According to the correlation analysis of the resonance characteristics of iron and oxygen and the elemental fractions, the iron oxides in the corroded reinforced concrete samples were accurately identified and mapped. The volume identification limit of the rust layer was further analyzed, and it is close to 0.1 mm. For the resonance energies of nuclides Fe-56 and O-16 in the tens and hundreds of keV range, the intensity of neutrons at the corresponding energy is only lower about three orders of magnitude after passing through a 40-cm-thick concrete block. The iron-oxide-identifying imaging method could also obtain a clear image of the iron-oxide distribution inside the 20-cm-thick corroded reinforced concrete sample.

Pascal conductance series in ballistic one-dimensional LaAlO3/SrTiO3 channels.

One-dimensional electronic systems can support exotic collective phases because of the enhanced role of electron correlations. We describe the experimental observation of a series of quantized conductance steps within strongly interacting electron waveguides formed at the lanthanum aluminate-strontium titanate (LaAlO3/SrTiO3) interface. The waveguide conductance follows a characteristic sequence within Pascal's triangle: (1, 3, 6, 10, 15, …) ⋅ e 2 /h, where e is the electron charge and h is the Planck constant. This behavior is consistent with the existence of a family of degenerate quantum liquids formed from bound states of n = 2, 3, 4, … electrons. Our experimental setup could provide a setting for solid-state analogs of a wide range of composite fermionic phases.

(+)-Borneol is neuroprotective against permanent cerebral ischemia in rats by suppressing production of proinflammatory cytokines.

Stroke is one of the leading causes of disability and death globally. It occurs when a major artery is occluded in the brain and leads to death of cells within the injured tissue. (+)-Borneol, a simple bicyclic monoterpene extracted from traditional Chinese medicine, is widely used in various types of diseases. However, no study has proved the effects of (+)-borneol on functional recovery from permanent ischemic stroke and the mechanism is still unknown. Here, we report that in the rat model of permanent cerebral ischemia, we found that (+)-borneol (1.0 mg/kg) significantly ameliorated infarct size and neurological scoresvia reducing the expression of inducible nitric oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-α) in a dose dependent manner. Notably, (+)-borneol showed long-term effects on the improvement of sensorimotor functions in the photothrombotic model of stroke, which decreased the number of foot faults in the grid-walking task and forelimb asymmetry scores in the cylinder task, at least in part through reducing loss of dendritic spines in the length, brunch number and density. These findings suggest that (+)-borneol could serve as a therapeutic target for ischemic stroke.

ZL006 promotes migration and differentiation of transplanted neural stem cells in male rats after stroke.

New strategies must be developed to resolve the problems of stroke treatment. In recent years, stem cell-based therapy after stroke has come into the public and academic lens. Previously we have shown that uncoupling neuronal nitric oxide synthase (nNOS) from the postsynaptic density protein-95 (PSD-95) by ZL006, a small molecular compound, can ameliorate ischemic damage and promote neuronal differentiation of endogenous neural stem cells (NSCs) in focal cerebral ischemic male rats. In this study, we transplanted exogenous NSCs into the ipsilateral hemisphere of male rats in combination with ZL006 treatment after ischemic stroke. We show that ZL006 treatment facilitates the migration of transplanted NSCs into the ischemia-injured area and promotes neuronal differentiation of these cells, which is not due to a direct effect of ZL006 on exogenous NSCs but is associated with increased phosphorylation of cAMP response element-binding protein (CREB) in neurons and favorable microenvironment. Moreover, improved functional outcome in the ZL006-treated group was also found. Taken together, our data indicate that ZL006, uncoupling nNOS-PSD-95 in neurons, positively regulates the fate of transplanted NSCs and benefits the functional outcome after stroke in male rats.

Landau Levels in Strained Optical Lattices.

We propose a hexagonal optical lattice system with spatial variations in the hopping matrix elements. Just like in the valley Hall effect in strained graphene, for atoms near the Dirac points the variations in the hopping matrix elements can be described by a pseudomagnetic field and result in the formation of Landau levels. We show that the pseudomagnetic field leads to measurable experimental signatures in momentum resolved Bragg spectroscopy, Bloch oscillations, cyclotron motion, and quantization of in situ densities. Our proposal can be realized by a slight modification of existing experiments. In contrast to previous methods, pseudomagnetic fields are realized in a completely static system avoiding common heating effects and therefore opening the door to studying interaction effects in Landau levels with cold atoms.

Comparison of periodontal ligament anesthesia and submucosal infiltration anesthesia in healthy volunteers.

OBJECTIVE: To compare periodontal ligament anesthesia using a computer-controlled local anesthetic delivery system (C-CLADS) and submucosal infiltration anesthesia using a manually operated syringe in terms of the injection pain, anesthetic effect, anesthetic dose, and complications in healthy volunteers. METHODS: Fifty healthy volunteers, aged 18 to 56 years, were recruited from September 2012 to May 2013 in the Department of Stomatology of Peking Union Medical College Hospital. A randomized self-controlled trial was conducted by applying a periodontal ligament anesthesia on one side and conventional manual submucosal infiltration anesthesia to the other (control) side. The differences in the onset time of anesthesia, drug dosage, anesthetic effect, and the degree of injection pain were compared. The complications associated with the two anesthesia methods were also recorded. RESULTS: When using C-CLADS to perform a periodontal ligament anesthesia, the drug dosage and the severity of injection pain were significantly less than those of conventional manual infiltration anesthesia [drug dosage: (0.34±0.09)ml vs.(0.55±0.13)ml, P<0.01; VRS: 0.42±0.73 vs. 1.38±0.92, P<0.01; VAS: 1.34±1.21 vs. 3.10±1.70, P<0.01]. The anesthesia success rate was approximately 90.0%, showing no significant difference relative to conventional submucosal infiltration anesthesia. Approximately 24% of the volunteers experienced postoperative pain after periodontal ligament anesthesia. CONCLUSION: Compared with conventional submucosal infiltration anesthesia using manual syringes, periodontal ligament anesthesia performed using C-CLADS can reduce the injection pain and drug dosage while achieving a satisfactory anesthetic effect; however, a considerable proportion of cases may experience postoperative pain.