Suppressing Sulfite Dimerization at a Polarized Gold Electrode/Water Solution Interface for High-Quality Gold Electrodeposition.

Solid/liquid interfacial structure occupies great importance in chemistry, biology, and materials. In this paper, by combining EC-SERS study and DFT calculation, we reveal the adsorption and dimerization of sulfite (SO32-) at a gold electrode/water solution interface, and establish an adsorption displacement strategy to suppress the dimerization of sulfite. At the gold electrode/sodium sulfite solution interface, at least two layers of SO32- anions are adsorbed on the electrode surface. As the applied potential shifts negatively, the adsorption strength of the first SO32- layer is weakened gradually and then is dimerized with the second orientated SO32- layer to form S2O52-, and S2O52- is further reduced to S2O32-. After hydroxyethylene disphosphonic acid (HEDP) is introduced to the gold electrode/sodium sulfite solution interface, the second oriented SO32- layer is replaced by a HEDP coadsorption layer. This results in the first layer of SO32- being desorbed directly without any structural transformation or chemical reaction as the potential shifts negatively. The suppression of sulfite dimerization by HEDP is more clear at the gold electrode/gold sulfite solution interface owing to the electroreduction of gold ions. Furthermore, the electrochemical studies and electrodeposition experiments show that as the sulfite dimerization reaction is suppressed, the electroreduction of gold ions is accelerated, and the deposited gold coating is bright and dense with finer grains.

Synergetic effect dependence on activated oxygen in the interface of NiOx-modified Pt nanoparticles for the CO oxidation from first-principles.

CO oxidation on NiOx-modified Pt nanoparticles (NPs) was investigated by first-principles calculations and microkinetic methods. The binding energies of O2 and CO on NiOx/Pt suggest that CO adsorption is dominant and the CO oxidation mainly follows the Mars-van Krevelen (M-vK) mechanism. It was found that the interfacial O of NiOx/Pt played a key role in the combination of adsorbed CO to O, as well as the O2 dissociation. With a lower O vacancy formation energy, NiOx/Ptedge shows about four orders higher reaction rates than NiOx/Pt(100). Microkinetic analysis suggests that the rate-determining step also depends on the active O at the interface. The calculations highlight the synergetic effect difference of NiOx selectively deposited on the different sites of Pt NPs on the CO oxidation from the atomic reaction mechanism, and throws light on the high activity of CO oxidation on partially covered NiOx/Ptedge nanoparticles.

The influence of adjacent Al atoms on the hydrothermal stability of H-SSZ-13: a first-principles study.

The Al concentration and distribution have a great influence on the hydrothermal stability of the H-SSZ-13 zeolites in experiments. In this work, first-principles calculations are performed to clarify the decomposition mechanism of an H-SSZ-13 framework with adjacent Al atom pair distribution under hydrothermal conditions. It is found that the adjacent Al atoms have a tendency to occupy the para-sites of the 4-membered rings (4MRs) in the framework. Water molecules are chemisorbed onto the Al atom one by one, and the hydroxylation of the neighboring O atoms induces the breaking of the Al-O bonds, which causes the first dealumination in 4MRs. The other Al atom in the para-site can be easily removed from the framework once the first one is lost. The feasible subsequent dealumination of adjacent Al atoms would break the linker of 6MRs in the framework, which is responsible for the degraded hydrothermal stability. Moreover, the partial substitution of metal ions (such as Na+ and Cu+) for the protons in the framework will greatly stabilize the Al-O bonds and enlarge the energy barrier of para-site Al dealumination, which leads to the improved hydrothermal stability of H-SSZ-13.

Ionic Liquid-Microwave-Based Extraction of Biflavonoids from Selaginella sinensis.

Selaginella sinensis (Desv.) Spring has been used for many years as traditional Chinese medicine (TCM) for many years. Recently, ionic liquids (ILs) have attracted great attentions in extraction and separation technology of TCM as a new green solvent. In this paper, microwave assisted extraction-IL (MAE-IL) that extracted amentoflavone (AME) and hinokiflavone (HIN) from Selaginella sinensis was reported for the first time. The contents of two biflavonoids were simultaneously determined by a high performance liquid chromatography (HPLC) method. After different ionic liquids were compared, it was found [C6mim]BF4 had a high selectivity and efficiency. Moreover, the important extraction conditions, including solid-liquid ratio, IL concentration, extraction time, microwave power and radiation temperature, were also investigated and optimized by response surface methodology (RSM) using AME and HIN yields as index. The results showed that the extraction yields of AME and HIN from S. sinensis were 1.96 mg/g and 0.79 mg/g, respectively, under the optimal process parameters (0.55 mmol/L, 300 W, 40 min, 1:11 g/mL and 48 °C). Compared with the conventional extraction methods, MAE-IL could not only achieve higher yield in shorter time, but also could reduce the consumption of solvent. This effective, rapid and green MAE-IL method was suitable for the extraction of AME and HIN.

Whole-genome sequencing of six dog breeds from continuous altitudes reveals adaptation to high-altitude hypoxia.

The hypoxic environment imposes severe selective pressure on species living at high altitude. To understand the genetic bases of adaptation to high altitude in dogs, we performed whole-genome sequencing of 60 dogs including five breeds living at continuous altitudes along the Tibetan Plateau from 800 to 5100 m as well as one European breed. More than 150× sequencing coverage for each breed provides us with a comprehensive assessment of the genetic polymorphisms of the dogs, including Tibetan Mastiffs. Comparison of the breeds from different altitudes reveals strong signals of population differentiation at the locus of hypoxia-related genes including endothelial Per-Arnt-Sim (PAS) domain protein 1 (EPAS1) and beta hemoglobin cluster. Notably, four novel nonsynonymous mutations specific to high-altitude dogs are identified at EPAS1, one of which occurred at a quite conserved site in the PAS domain. The association testing between EPAS1 genotypes and blood-related phenotypes on additional high-altitude dogs reveals that the homozygous mutation is associated with decreased blood flow resistance, which may help to improve hemorheologic fitness. Interestingly, EPAS1 was also identified as a selective target in Tibetan highlanders, though no amino acid changes were found. Thus, our results not only indicate parallel evolution of humans and dogs in adaptation to high-altitude hypoxia, but also provide a new opportunity to study the role of EPAS1 in the adaptive processes.

Hydrogenous spinel γ-alumina structure.

The structure of γ-Al2O3 is still under debate. Here we report a H spinel structure evolved from pseudo-boehmite. A unit cell with two octahedral cationic vacancies and one bulk H was preferential in terms of calculated Gibbs energy, which was well consistent with experimental data. Bulk H was found to migrate out with elevated temperatures. Through calculating the migration barriers of every step, we observed that the "hopping" step was rate-determining. The hopping rates were further estimated by assuming a Boltzmann distribution of energies, and as a result they increased by 2 to 3 orders of magnitude from 500 °C to 800 °C. This investigation will encourage us to study more uncertainties in material structures.

Identification and Characterization of the Gene CYP340W1 from Plutella xylostella and Its Possible Involvement in Resistance to Abamectin.

Abamectin has been used to control the diamondback moth, Plutella xylostella (P. xylostella), which is a major agricultural pest that can rapidly develop resistance against insecticides including abamectin. Although cytochrome P450 has been confirmed to play an important role in resistance in P. xylostella, the specific P450 genes associated with the resistance are unclear. The full-length cDNA of the cytochrome P450 gene CYP340W1 was cloned and characterized in the present study. The cDNA assembly yielded a sequence of 1929 bp, containing the open reading frame (ORF) 1491 bp and encodes a 496-amino acid peptide. CYP340W1 was expressed in all P. xylostella developmental stages but its expression level was highest in larvae and especially in the heads of larvae. The expression of CYP340W1 was significantly higher in an abamectin-resistant strain (ABM-R) than in its susceptible counterpart (ABM-S). In addition, expression of CYP340W1 was increased when the ABM-R strain was exposed to abamectin. When injected into third-stage ABM-R larvae, CYP340W1 dsRNA significantly reduced CYP340W1 expression at 6 h and reduced expression by 83% at 12 h. As a consequence of RNAi, the mortality of the injected abamectin-resistant larvae increased after a 48-h exposure to abamectin. The results indicate that the overexpression of CYP340W1 plays an important role in abamectin resistance in P. xylostella.

[Synthesis and antitumor activity of cinnamoyloxy phosphonate derivatives].

In search of more effective anticancer agents, twelve compounds were designed and synthesized via microwave-assisted reactions of cinnamoyl chloride with α-hydroxyphosphonate. The structures of all the compounds were confirmed by IR, NMR and elemental analysis. Bioassay of the compounds were tested. They exhibited certain antitumor activities. Especially, compound 3c had obvious inhibitory effect on growth of SGC-7901 cells in vitro at 20 µmol·L(-1), and compound 3h showed better inhibitory effect on growth of SGC-7901 cells in vitro at 5 µmol·L(-1), the inhibition ratio were 68.8% and 48.0%, respectively.

[Synthesis and antitumor activity of phosphonate derivatives containing amino acid].

In search of effective anticancer agents, fifteen new phosphonate derivatives were designed and synthesized. Their structures were clearly established by elemental analysis, IR, (1)H NMR and (13)C NMR, and their antitumor activities were evaluated by MTT assay. Preliminary results in bioactivity tests indicated that some title compounds exhibited better activity. Among the active compounds, compounds 4e, 4n had better inhibition effect on A-549 cells growth with IC(50) values of 8.7 ± 0.8, 8.2 ± 1.0 µmol·L(-1), the IC(50) values of compound 4c was 9.8 ± 0.9 µmol·L(-1) against SGC-7901 cells and compounds 4l, 4n exhibited more potent activities against EC-109 with IC(50) values of 9.5 ± 0.6, 9.4 ± 0.5 µmol·L(-1).

[Design, synthesis and antitumor activities of novel E-substituted 2,3-diaryl propenoic acyloxy phosphonate derivatives].

According to the super-position principle of the reinforcement of biological activities, a series of novel E-substituted 2, 3-diaryl propenoic acyloxy phosphonate derivatives were designed and synthesized. And the structures of the target compounds were confirmed by IR, 1H NMR, 13C NMR and elemental analysis. Furthermore, the cytotoxicities of all compounds on A-549, SGC-7901 and EC-109 in vitro were evaluated by MTT assay, and some of them showed good antitumor activity. Among the active compounds, especially, the IC50 value of compound 3e was (12.7 ± 1.9) µmol x L(-1) against A-549 cells, similar to cisplatin [IC50 = (8.0 ± 1.5) µmol x L(-1)], compounds 3g and 3k had better inhibition effect on EC-109 cells growth, with the IC50 values of (9.5 ± 1.8) µmol x L(-1) and (11.5 ± 0.9) µmol x L(-1) respectively, and compounds 3i and 3k exhibited good cytotoxic property on A-549, SGC-7901 and EC-109, which were worth further investigation.

Expression and function of VISTA on myeloid cells.

V-domain containing Ig Suppressor of T cell Activation (VISTA) is predominantly expressed on myeloid cells and functions as a ligand/receptor/soluble molecule. In inflammatory responses and immune responses, VISTA regulates multiple functions of myeloid cells, such as chemotaxis, phagocytosis, T cell activation. Since inflammation and immune responses are critical in many diseases, VISTA is a promising therapeutic target. In this review, we will describe the expression and function of VISTA on different myeloid cells, including neutrophils, monocytes, macrophages, dendritic cells (DCs), myeloid-derived suppressor cells (MDSCs). In addition, we will discuss whether the functions of VISTA on these cells impact the disease processing.

Molecular cloning and characterization of a P-glycoprotein from the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae).

Macrocyclic lactones such as abamectin and ivermectin constitute an important class of broad-spectrum insecticides. Widespread resistance to synthetic insecticides, including abamectin and ivermectin, poses a serious threat to the management of diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), a major pest of cruciferous plants worldwide. P-glycoprotein (Pgp), a member of the ABC transporter superfamily, plays a crucial role in the removal of amphiphilic xenobiotics, suggesting a mechanism for drug resistance in target organisms. In this study, PxPgp1, a putative Pgp gene from P. xylostella, was cloned and characterized. The open reading frame (ORF) of PxPgp1 consists of 3774 nucleotides, which encodes a 1257-amino acid peptide. The deduced PxPgp1 protein possesses structural characteristics of a typical Pgp, and clusters within the insect ABCB1. PxPgp1 was expressed throughout all developmental stages, and showed the highest expression level in adult males. PxPgp1 was highly expressed in midgut, malpighian tubules and testes. Elevated expression of PxPgp1 was observed in P. xylostella strains after they were exposed to the abamectin treatment. In addition, the constitutive expressions of PxPgp1 were significantly higher in laboratory-selected and field-collected resistant strains in comparison to their susceptible counterpart.

Indoor Positioning on Smartphones Using Built-In Sensors and Visual Images.

With the rapid development of mobile Internet technology, localization using visual image information has become a hot problem in the field of indoor localization research, which is not affected by signal multipath and fading and can achieve high accuracy localization in indoor areas with complex electromagnetic environments. However, in practical applications, position estimation using visual images is easily influenced by the user's photo pose. In this paper, we propose a multiple-sensor-assisted visual localization method in which the method constructs a machine learning classifier using multiple smart sensors for pedestrian pose estimation, which improves the retrieval efficiency and localization accuracy. The method mainly combines the advantages of visual image location estimation and pedestrian pose estimation based on multiple smart sensors and considers the effect of pedestrian photographing poses on location estimation. The built-in sensors of smartphones are used as the source of pedestrian pose estimation data, which constitutes a feasible location estimation method based on visual information. Experimental results show that the method proposed in this paper has good localization accuracy and robustness. In addition, the experimental scene in this paper is a common indoor scene and the experimental device is a common smartphone. Therefore, we believe that the proposed method in this paper has the potential to be widely used in future indoor navigation applications in complex scenarios (e.g., mall navigation).

Origin of Ammonia Selective Oxidation Activity of SmMn2O5 Mullite: A First-Principles-Based Microkinetic Study.

Based on first-principles calculations and microkinetic analysis, the reaction routes and origin of the activity of SmMn2O5 mullite for the selective catalytic oxidation of ammonia (NH3-SCO) are systematically investigated on three low-index surfaces under experimentally operating conditions. Key influencing factors and contributions of different iconic intermediate species (NH*, N2H4*, and HNO*) to the overall reaction process have been identified. In detail, Mn4+ serves as the primary active site for NH3 adsorption, while lattice oxygen participates in the dehydrogenation of NH3 on (010)4+ and (001)4+ surfaces. Furthermore, the (010)4+ surface shows both the best activity and the highest N2 selectivity at low temperatures via the synergy effect of exposed Mn-Mn dimers and the most labile O2 atoms. We further evaluate the potential catalytic performances of six A-site doped (010)4+ facets, among which La, Pr, and Nd dopings are predicted to possess better catalytic performances. Our study provides deep insights into the microscope reaction mechanisms and provides the specific optimization strategy for NH3-SCO on mullite oxides.

Advanced Ag nanoparticles for the catalyzation of glyoxylic acid oxidation in through-holes electroless copper metallization.

Advanced Ag nanoparticles (Ag NPs) were prepared by wet chemical oxidation-reduction method, using mainly the tannic acid as reducing agent and carboxymethylcellulose sodium as stabilizer. The prepared Ag NPs uniformly disperse and are stable for more than one month without agglomeration. The studies of transmission electron microscopy (TEM) and ultraviolet-visible (UV-vis) absorption spectroscopy indicate that the Ag NPs are in homogeneous sphere with only 4.4 nm average size and narrow particle size distribution. Electrochemical measurements reveal that the Ag NPs behave excellent catalytic activity for electroless copper plating using glyoxylic acid as reducing agent. In situ fourier transform infrared (in situ FTIR) spectroscopic analysis combined with density functional theory (DFT) calculation illustrate that the molecular oxidation of glyoxylic acid catalyzed by Ag NPs is as the following routes: glyoxylic acid molecule first is adsorbed on Ag atoms with carboxyl oxygen terminal, then hydrolyzed to diol anionic intermediate, and last oxidized to oxalic acid. Time-resolved in situ FTIR spectroscopy further reveals the real-time reactions of electroless copper plating as follows: glyoxylic acid is continuously oxidized to oxalic acid and releases electrons at the active catalyzing spots of Ag NPs, and Cu(II) coordination ions are in situ reduced by the electrons. Based on the excellent catalytic activity, the advanced Ag NPs can replace the expensive Pd colloids catalyst and successfully apply in through-holes metallization of printed circuit board (PCB) by electroless copper plating.

[Analysis on the diagnosis and treatment of a cluster of cases infected by new bunyavirus].

OBJECTIVE: To analyze and summarize the clinical characteristics, experience of diagnosis and treatment of cases infected by new bunyavirus, which occurred in Henan province in 2010. METHODS: The clinical characteristics and effect of diagnosis and treatment of 5 cases were analyzed using descriptive epidemiological method. Blood specimens were detected by RT-PCR and pathogen separation. RESULTS: PCR testing was positive for all 5 cases. New bunyavirus were isolated from 2 cases. In 5 cases, fever (5/5), the whole body aches (5/5), fatigue (5/5), anorexia (5/5), nausea (5/5), the chills (4/5), cough (4/5), expectoration (4/5), vomiting (3/5), conjunctival hyperemia (3/5); Leukocyte reduction (5/5), thrombocytopenia (5/5), elevated alanine aminotransferase (4/5), elevated aspartate aminotransferase (4/5), elevated lactate dehydrogenase (5/5), creatine kinase elevations (4/5), urinary protein (3/5). By symptomatic and supportive treatment and prophylactic antibiotics, the first case died and the other 4 cases were cured. The average course of disease was 15.4 days. CONCLUSION: Cases infected by new bunyavirus have complicated clinical feature and multiple organ damage. If symptomatic treatment is in time, prognosis will be good.

Promotional Effect of H2 Pretreatment on the CO PROX Performance of Pt1/Co3O4: A First-Principles-Based Microkinetic Analysis.

Atomic Pt studded on cobalt oxide is a promising catalyst for CO preferential oxidation (PROX) dependent on its surface treatment. In this work, the CO PROX reaction mechanism on Co3O4 supported single Pt atom is investigated by a comprehensive first-principles based microkinetic analysis. It is found that as synthesized Pt1/Co3O4 interface is poisoned by CO in a wide low temperature window, leading to its low reactivity. The CO poisoning effect can be effectively mitigated by a H2 prereduction treatment, that exposes Co ∼ Co dimer sites for a noncompetitive Langmuir-Hinshelhood mechanism. In addition, surface H atoms assist O2 dissociation via "twisting" mechanism, avoiding the high barriers associated with direct O2 dissociation path. Microkinetic analysis reveals that the promotion of H-assisted pathway on H2 treated sample helps improve the activity and selectivity at low temperatures.

The study of immune checkpoint inhibitors in chronic hepatitis B virus infection.

Chronic hepatitis B (CHB) is a contagious disease caused by the hepatitis B virus, which can damage the liver via cirrhosis or cancer. Existing CHB treatments are not completely effective; immune checkpoint inhibitors show potential hope for treating CHB, but their safety and efficacy need to be further validated. In this review, we introduce the mechanisms of CHB virus infection, the expression of immune checkpoints during CHB, and the treatments that are currently available. Finally, we discuss the possibilities for using immune checkpoint inhibitors to treat CHB.

Association between the platelet-lymphocyte ratio and short-term mortality in patients with non-ST-segment elevation myocardial infarction.

BACKGROUND: Previous studies have shown that inflammation plays an important role in atherosclerosis and cardiovascular disease. Platelet to lymphocyte ratio (PLR) has been reported as a novel inflammatory marker. However, it is not clear whether PLR is associated with short-term all-cause mortality in critically ill patients with non-ST-segment elevation myocardial infarction (NSTEMI). METHODS: The data for the study is from the Medical Information Mart for Intensive Care III database. The primary outcome in our study was 28-day mortality. Kapan-Meier curve, lowess smoother curve, and multivariate Cox regression models were used to determine whether the association between PLR and 28-day mortality of critically ill patients with NSTEMI. RESULTS: A total of 1273 critically ill patients with NSTEMI were included in this analysis. Kapan-Meier curve and lowess smoother curve show that high PLR is associated with an increased risk of 28-day all-cause mortality. The study population is divided into two groups according to the cut-off value of PLR level. In the Cox model, high PLR levels (PLR≥195.8) were significantly associated with increased 28-day mortality (HR 1.54; 95%CI 1.09-2.18, p = .013). In quartile analyses, the HR (95% CI) for the third (183 ≤ PLR < 306) and fourth quartile (PLR≥306) was 1.55 (1.05-2.29) and 1.61 (1.03-2.52), respectively, compared to the reference group(111 ≤ PLR < 183). In subgroup analyses, there is no interaction effect in most of the subgroups except for respiratory failure and vasopressor use. CONCLUSION: High PLR is associated with an increased risk of short-term mortality in critically ill patients with NSTEMI.

[Comparison of rDNA internal transcribed spacer sequences in asparagus].

OBJECTIVE: Using ITS sequence of nine species to identify counterfeiting medicine and analyse phylogenetic of Asparagus. METHODS: Analysing ITS sequences by amplification, cloning,sequencing and alignment. RESULTS: The length range of ITS sequence of nine species was from 711 to 748 bp, the percentage of G + C content was about 60%. The phylogenetic tree constructed on the basis of the ITS sequences showed that nine species were divided into two branches: Asparagus cochinchinensis, Asparagus officinalis, Asparagus densiflorus, Asparagus densiflorus cv. Myers and Asparagus densiflorus cv. Sprengeri were a branch and the others were a branch. Asparagus densiflorus and Asparagus densflorus cv. Myers those were from Africa had priority to clustering and then clustering with Asparagus densiflorus cv. Sprengeri that was a variant of Asparagus densiflorus in the first branch. Asparagus setaceus had relatively distant genetic relationship with the others three materials in another branch. CONCLUSIONS: The ITS sequences could distinguish species of Asparagus to test the counterfeit. Division status in phylogenetic tree of some species were debatable and ITS sequence was combined with others analytical tools to analyze the realistic phylogeny.