A computational study of the HO2 + SO3 → HOSO2 + 3O2 reaction catalyzed by a water monomer, a water dimer and small clusters of sulfuric acid: kinetics and atmospheric implications.

Herein, the reaction mechanisms and kinetics for the HO2 + SO3 → HOSO2 + 3O2 reaction catalyzed by a water monomer, a water dimer and small clusters of sulfuric acid have been studied theoretically by quantum chemical methods and the Master Equation/Rice-Ramsperger-Kassel-Marcus (ME/RRKM) rate calculations. The calculated results show that when H2O is introduced into the HO2 + SO3 reaction, it not only enhances the stability of the reactant complexes by 9.0 kcal mol-1 but also reduces the energy of the transition state by 8.7 kcal mol-1. As compared with H2O, catalysts (H2O)2, H2SO4, H2SO4⋯H2O and (H2SO4)2 are more effective energetically, which not only results from a higher binding energy of 21.3-26.0 kcal mol-1 for the reactant complexes but also from a reduction of the energy of the transition states by 8.6-17.2 kcal mol-1. Effective rate constant calculations show that, as compared with H2O, catalysts (H2O)2, H2SO4, H2SO4⋯H2O and (H2SO4)2 can never become more efficient catalysts within the altitude range of 0-15 km due to their relatively lower concentrations. Besides, at 0 km altitude, the enhancement factor for the H2O and (k'WD1/ktot) (H2O)2-assisted HO2 + SO3 reaction within the temperature range of 280-320 K was respectively calculated to be 0.31%-0.34% and 0.16%-0.27%, while the corresponding enhancement factor of H2O and (H2O)2 at higher altitudes of 5-15 km was respectively found only 0.002%-0.12% and 0.00001%-0.022%, indicating that the contributions of H2O and (H2O)2 are not apparent in the gas-phase reaction of HO2 with SO3 especially at higher altitude. Overall, the present work will give a new insight into how a water monomer, a water dimer and small clusters of sulfuric acid catalyze the HO2 + SO3 → HOSO2 + 3O2 reaction.

Exploring the NT-proBNP expression in Premature Infants with Patent Ductus Arteriosus (PDA) by Echocardiography.

OBJECTIVES: To investigate the correlation between echocardiographic indicators and the expression level of N-terminal pro-brain natriuretic peptide (NT-proBNP) in premature infants (PIs) with patent ductus arteriosus (PDA) and the value of NT-proBNP in diagnosing symptomatic PDA (sPDA) in PIs whose gestational age (GA) was less than 32 weeks. METHODS: Ninty premature infants were selected as the research objects, including 52 in the non-PDA group and 38 in the PDA group (26 sPDA cases and 12 cases with asymptomatic PDA (asPDA)) from February 2019 to March 2020. The general information of these infants was recorded, including gender, delivery method, maternal infection, and serum NT-proBNP level on the 3rd day after birth. They were screened by echocardiographic indicators under an artificial intelligence convolutional neural network (AI-CNN). The Receiver Operating Characteristic (ROC) curves were illustrated to decide serum NT-proBNP expression levels, thereby determining specificity and sensitivity of sPDA and the correlation between serum sPDA NT-proBNP expression and echocardiographic indicators. RESULTS: The expression level of serum NT-proBNP in the sPDA group was greater than that in the asPDA group and the non-PDA group (P<0.001). The serum NT-proBNP expression level was positively correlated with the diameter of the ductus arteriosus in the sPDA group (r=0.462, P<0.001); it was also positively correlated with the ratio of left atrium/aorta (LA/AO) (r=0.573, P<0.001), but was not correlated with left ventricular ejection fraction (LVEF) (r=-0.015, P=0.747). CONCLUSION: The combination of serum NT-proBNP expression and echocardiography had clinical values in early diagnosis of PDA.

Application of CT images based on the optimal atlas segmentation algorithm in the clinical diagnosis of Mycoplasma Pneumoniae Pneumonia in Children.

OBJECTIVE: Use of optimal Atlas segmentation algorithm to study the imaging signs of mycoplasma pneumonia with multi-slice spiral CT (HRCT), and to explore the value of HRCT in the diagnosis and efficacy in evaluation of mycoplasma pneumonia in children. METHODS: The study retrospectively analyzed 72 patients diagnosed with mycoplasma pneumonia in our hospital from January 2017 to January 2019. The imaging data and clinical data of 72 patients were collected. The optimal Atlas segmentation algorithm was used to analyze the characteristics of CT examination, and the value of CT in the diagnosis of mycoplasma pneumonia and the evaluation of curative effect was summarized. RESULTS: Among all patients, 37 cases were unilateral lesions, 35 cases were bilateral lesions, 19 cases were in the left upper lobe, 24 cases were in the left lower lobe, 21 cases were in the right upper lobe, 13 cases were in the right middle lobe, 25 The lesion was located in the right lower lobe. The main CT findings of the lesions before treatment were large patchy, spot-shaped shadows, and strip-shaped or ground-glass shadows. After treatment, the main CT findings of the lesions were reduced lesion density and reduced lesion range. CONCLUSION: CT can clearly show the pulmonary lesions of mycoplasma pneumonia, and its unique imaging signs can improve the clinical diagnosis accuracy. In addition, CT scans can evaluate the treatment effect according to the changes in the characteristics of the lesion, which has important value for the evaluation of the effect for clinical diagnosis and efficacy evaluation of mycoplasma pneumonia.

Application of block matching method-based Echocardiography combined with serum NT-PROBNP level detection in the early prediction of PDA in premature infants.

OBJECTIVES: The paper uses block matching method combined with echocardiography to explore the value of N-terminal pro-brain natriuretic peptide (NT-proBNP) in predicting symptomatic patent ductus arteriosus (PDA) in preterm infants. METHODS: We selected premature infants born between February 2019 and March 2020, gestational age ≤32 weeks, and echocardiography within 48 hours to determine the presence of arterial ducts as the research object, monitor their clinical manifestations, and detect serum at three and five days after birth The level of NT-proBNP was checked with echocardiography, and the children were divided into PDA group and asymptomatic patent ductus arteriosus (aPDA) group according to the clinical manifestations and echocardiographic. RESULTS: The area under the ROC curve of PDA predicted by serum NT-proBNP level at 3 days after birth was 0.949, the cut-off value was 27035pg/mL, the sensitivity was 92.3%, and the specificity was 94.6%; serum NT-proBNP level at 5 days after birth predicted the ROC curve of PDA The lower area is 0.924, the critical value is 6411 pg/mL, the sensitivity is 92.3%, and the specificity is 92.9%. CONCLUSION: NT-proBNP may be a quantitative indicator of arterial duct shunt; the detection of serum NT-proBNP levels at 3 and 5 days after birth is helpful for early prediction of PDA.

Brain tissue development of neonates with Congenital Septal Defect: Study on MRI Image Evaluation of Deep Learning Algorithm.

OBJECTIVES: This article is based on deep learning algorithms and uses MRI to study the development of congenital heart septal defects in neonatal brain tissue. METHODS: From January 2018 to December 2019, 150 cases of congenital cardiac paper septal defect were retrospectively analyzed on 50 cases of normal newborns and neonates. The four index parametersbrain MR imaging, lateral ventricle pre-angle measurement index (F/F'), body index (D/ D'), caudal nucleus index (C/C') were analyzed. The independent sample t test is performed to compare the difference parameters between groups. RESULTS: F congenital heart disease group and control group/F 'values were 0.301 ± 0.035 and 0.296 ± 0.031; Evans index was 0.239 ± 0.052 and 0.233 ± 0.025; 2 sets of D/D' values were 0.261 ± 0.039 and 0.234 ± 0.032; C/C 'value was 0.138 ± 0.018 and 0.124 ± 0.015 respectively. The congenital heart disease group D/D ', and the value of C/C' obtained under the ROC curve area value, respectively 0.698 and 0.750, Youden index corresponding to the maximum D/D ', and the value of C/C' values were 0.28 and 0.12. CONCLUSION: Lateral ventricle D/D 'and C/C' is more sensitive indicator which can be evaluated with the difference between the volume of congenital heart septal defects in newborn normal neonatal brain; when the D/D 'value> 0.28, C/C' value> 0.12. For the diagnosis and evaluation of congenital heart septal defect neonatal brain volume abnormalities have a certain reference value.

Evaluation of illness severity of neonate infectious pneumonia and neurobehavioral development through ultrasonography under adaption algorithm.

OBJECTIVES: To explore the diagnostic effect of ultrasound imaging on the illness severity, and to analyze neurobehavioral development of neonates with Infectious Pneumonia (IPN), Self- Adaptation (SD), and Spatial Smoothing (SS) technologies were adopted to build SDSS. Then, the WFFSF algorithm based on Wiener Filtering (WF) and Feature Space Fusion (FSF) and the SNRP-FSF algorithm based on Signal-to-noise ratio post-filtering (SNRP) and FSF were introduced for comparison. METHODS: One hundred and thirty-two neonates were divided into group without respiratory failure (S1) and respiratory failure group (S2). The study was conducted from March 2018 to July 2020. According to scoring systems for neonatal critically illness, they were divided into non-severe group (W1), severe group (W2), and extremely-severe group (W3). According to the Scale of Child Development Center of China (CDCC), they were divided into a normal neurobehavioral developmental group (P1) and an abnormal neurobehavioral developmental group (P2). RESULTS: The normalized mean square distance l and normalized mean absolute distance f of SDSS algorithm were significantly lower than that of WFFSF algorithm and SNRP-FSF algorithm, and the peak signal-to-noise ratio (PSNR) was significantly higher than that of WFFSF algorithm and SNRP-FSF algorithm (P<0.05). The lung ultrasound score (40.62±7.22%) of S1 was greatly higher than S2 group (28.47±6.29%) (P<0.05); the lung ultrasound score (39.13±8.25) in W1 was greatly higher than W2 (27.28±6.39) and W3 groups (14.33±7.03); neonates in group W2 had higher lung ultrasound scores than W3 (P<0.05), and lung ultrasound scores in P1 (42.57±8.58) was greatly higher than that the P2 group (26.49±6.09). CONCLUSION: In contrast with traditional algorithms, the SDSS algorithm based on AD has a better reconstruction effect on neonatal IPN ultrasound images. The lung ultrasound score can clearly indicate the severity of the disease and neurobehavioral development of neonate IPN, and the lung ultrasound score is negatively correlated with the severity of the child's disease and the abnormality of neurobehavioral development.

Theoretical modeling and analysis of material removal characteristics for KDP crystal in abrasive-free jet processing.

Traditional KDP polishing methods, such as magnetorheological finishing (MRF), ion-beam figuring (IBF), and chemical mechanical polishing (CMP), are limited by either hard-to-remove residual particles, unavoidable heating effect, or applicability that is restricted to large-sized KDP. The abrasive-free jet polishing (AFJP) is regarded as a promising polishing method that can circumvent the above issues. KDP AFJP makes use of a thermodynamically and kinetically stable ionic liquid (IL) microemulsion that contains nanometer range water droplets evenly dispersed in the non-aqueous carrier liquid. The sprayed out nanoscale water droplets can remove material through dissolution. In this paper, the normal impinging of a nanoscale water droplet on the KDP surface is investigated. And then a materials removal model is proposed for water droplets. This model considers two major modes, namely deformation of a water droplet in compressing and deformation restoring of a water droplet in slipping process. Finally, KDP AFJP spot experiments were then conducted to validate the model veracity. The proposed model fits well with the simulation and experimental results which further suggest KDP AFJP's feasibility. This proposed model provides a good explanation for KDP AFJP's removal mechanism.

Investigation of roughness evolution of ion sputtered fused silica surface.

Ion beam polishing (IBP) has been widely used in smooth surface manufacturing. Nevertheless, the evolution of the process and mechanisms of the change in surface roughness have not yet been fully clarified. In this paper, the evolution of surface morphology at the micrometer scale under IBP is studied. First, a series of experimental results indicate that the results at the nanometer and micrometer scales are not consistent. Second, a two-step positioning method that can accurately acquire a contour location before and after polishing is proposed to improve the reliability of the experimental results at the micrometer scale. This method can help analyze the effect of surface morphology on the amount of material removal and can eliminate errors introduced by the method of averaging measurements at different positions selected randomly. Furthermore, a correlation analysis is conducted between the profiles of the amount of material removal and the initial contours, at the micrometer scale. A similarity is revealed between the removal amount and the initial morphology. Finally, a simulation of the evolution process of morphology is performed, based on the dominant smoothing mechanism. It is consistent with the experimental results. The simulation reveals that the mass redistribution of surface atoms, induced by the ion beam, plays an important role in the evolution of the micromorphology of the surface. The analysis helps to further research on roughness optimization at the micrometer scale.

Estimation of Solar Radiation for Tomato Water Requirement Calculation in Chinese-Style Solar Greenhouses Based on Least Mean Squares Filter.

The area covered by Chinese-style solar greenhouses (CSGs) has been increasing rapidly. However, only a few pyranometers, which are fundamental for solar radiation sensing, have been installed inside CSGs. The lack of solar radiation sensing will bring negative effects in greenhouse cultivation such as over irrigation or under irrigation, and unnecessary power consumption. We aim to provide accurate and low-cost solar radiation estimation methods that are urgently needed. In this paper, a method of estimation of solar radiation inside CSGs based on a least mean squares (LMS) filter is proposed. The water required for tomato growth was also calculated based on the estimated solar radiation. Then, we compared the accuracy of this method to methods based on knowledge of astronomy and geometry for both solar radiation estimation and tomato water requirement. The results showed that the fitting function of estimation data based on the LMS filter and data collected from sensors inside the greenhouse was y = 0.7634x + 50.58, with the evaluation parameters of R2 = 0.8384, rRMSE = 23.1%, RMSE = 37.6 Wm-2, and MAE = 25.4 Wm-2. The fitting function of the water requirement calculated according to the proposed method and data collected from sensors inside the greenhouse was y = 0.8550x + 99.10 with the evaluation parameters of R2 = 0.9123, rRMSE = 8.8%, RMSE = 40.4 mL plant-1, and MAE = 31.5 mL plant-1. The results also indicate that this method is more effective. Additionally, its accuracy decreases as cloud cover increases. The performance is due to the LMS filter's low pass characteristic that smooth the fluctuations. Furthermore, the LMS filter can be easily implemented on low cost processors. Therefore, the adoption of the proposed method is useful to improve the solar radiation sensing in CSGs with more accuracy and less expense.

Serum fetuin-A concentrations are positively associated with serum VEGF levels in patients with newly diagnosed type 2 diabetes.

Fetuin-A was considered to be involved in pathogenesis of type 2 diabetes. On the other hand, higher vascular endothelial growth factor (VEGF) expression is associated with diabetes and its vascular complications, but the mechanisms leading to higher VEGF levels are still not clear. To the best of our knowledge, there are no data to show the associations between fetuin-A and VEGF in patients with type 2 diabetes. Therefore, the aim of this study is to investigate the relationship between serum fetuin-A concentrations and serum VEGF levels in patients with type 2 diabetes. We recruited 345 patients with newly diagnosed type 2 diabetes. Serum fetuin-A concentrations and serum VEGF levels were measured using enzyme-linked immunosorbent assay (ELISA) method. In this study, there was a significant positive correlation between serum fetuin-A concentrations and serum VEGF levels (r=0.223, P<0.001), and the correlation remained significant even after adjustment for other confounding factors in the multivariate regression model (ß=0.151, P=0.006). Mantel-Haenszel (M-H) stratified analysis showed that the degree of association of high concentrations of fetuin-A with high levels of VEGF is higher than that with low levels of VEGF (odds ratio of M-H [ORM-H], 2.938; 95% confidence interval [CI], 1.896-4.553). In addition, this study showed that both fetuin-A and VEGF were positively associated with fasting plasma glucose (FPG), glycated hemoglobin A1c (HbA1c) and C-reactive protein (CRP). These data suggested that serum fetuin-A concentrations were positively associated with serum VEGF levels in patients with newly diagnosed type 2 diabetes.

Exciton coupling of surface complexes on a nanocrystal surface.

Exciton coupling may arise when chromophores are brought into close spatial proximity. Herein the intra-nanocrystal exciton coupling of the surface complexes formed by coordination of 8-hydroxyquinoline to ZnS nanocrystals (NCs) is reported. It is studied by absorption, photoluminescence (PL), PL excitation (PLE), and PL lifetime measurements. The exciton coupling of the surface complexes tunes the PL color and broadens the absorption and PLE windows of the NCs, and thus is a potential strategy for improving the light-harvesting efficiency of NC solar cells and photocatalysts.

Low Serum Vascular Endothelial Growth Factor Level Predicts Adverse Outcomes in Neonates with Respiratory Distress Syndrome.

Objective: Preterm neonates are susceptible to neonatal respiratory distress syndrome (NRDS). Lower levels of cord blood vascular endothelial growth factor (VEGF) are implicated in NRDS. This study aims to explore whether the serum VEGF level has prognostic values on neonates with respiratory distress syndrome (RDS). Methods: A total of 80 infants diagnosed with NRDS were enrolled, with 70 preterm neonates without NRDS as controls. Cord blood samples before treatment and venous blood samples after treatment were collected and clinical information was recorded. The serum VEGF level was measured using enzyme-linked immunosorbent assay kits. Receiver operating characteristic (ROC) curve was used to evaluate whether serum VEGF is a biomarker of NRDS. Newborns were followed up for 1 month to collect survival information. The influence of VEGF levels on overall survival was analyzed using the Kaplan-Meier method. The univariate and multivariate Cox regression models were adopted to assess the prognostic factor of NRDS. Results: VEGF level was decreased in sera of neonates with RDS. The area under the ROC curve of VEGF level in distinguishing neonates with RDS from neonates without RDS was 0.949, with a cutoff value of 39.72 (87.50% sensitivity, 87.14% specificity). Serum VEGF was a biomarker of NRDS. Neonates with RDS with high VEGF levels had longer periods of survival than those with low VEGF levels. NRDS grade and VEGF level were independent prognostic factors affecting the overall survival of neonates with RDS. Conclusion: Decreased serum VEGF level in RDS neonates can predict the poor prognosis of NRDS, and VEGF level might be an independent prognostic factor for the overall survival of RDS neonates. Clinical Trial Registration No. 201901A.

A microenvironment prediction model for Chinese solar greenhouses based on the bond graph approach.

To improve the prediction accuracy of temperature and humidity in typical Chinese solar greenhouses, this paper proposed a new longwave/shortwave radiation modeling method using bond graph. This model takes into account sun position, useful incoming solar radiation model, sky longwave radiation model, inside longwave, and shortwave radiation model. The approach solves the problems caused by underestimating the effects of longwave radiation on night temperature and relative humidity. The study found that after a period of t = 7.5 h, with the increase of sun altitude angle, the internal temperature was significantly affected by the temperature rise of outside environment on sunny day. The sun altitude angle gradually falls over a period of t = 12.5 h (beginning at 12.30 p.m.). The decline in night temperature steadily slowed after a period of t = 20.5 h. On the other hand, the temperature variation has a multi-peak distribution and the warming rate of the CSG slows down on cloudy days. Furthermore, a good agreement between the experimental and simulation data were obtained, with a maximum temperature deviation of 2°C and maximum humidity deviation of 5%. The developed model is a universal and valuable approach that can be used for greenhouse climate simulation. Furthermore, it can be used as a support system during decision-making processes to help manage Chinese solar greenhouses more efficiently, which provides several control perspectives on the low-energy greenhouse in the future. This work has also provided several control perspectives on the low energy greenhouse in the future.

Study of a novel front-roof-back natural ventilation system for Chinese solar greenhouses.

A Chinese solar greenhouse (CSG) is a highly efficient and energy-saving horticultural facility. Ventilation is significantly important for crop production in the greenhouse, and the vent configuration is the basis of the greenhouse design. Current CSG ventilation structures mostly include front bottom vents and top vents to create a suitable temperature environment for the normal development of crops. However, the ventilation capacity and efficiency are limited. In the present study, we proposed a comprehensive front bottom + top + back roof (FTB) ventilation configuration. The greenhouse ventilation was investigated during the summer season by means of field testing and simulation, and the performance of three ventilation structures-front bottom + top (FT), front bottom + back roof (FB) and FTB-was compared. The results showed that FTB stabilized the greenhouse temperature for 20 s less time than FT and FB. The cooling rate of FTB showed a 24.84% and 5.52% improvement over FT and FB, respectively, and the average temperature showed a 13.81% and 3.65% decrease, respectively. Moreover, the ventilation performance of the side walls was investigated in order to determine if they might serve as auxiliary structures for FTB ventilation. Nevertheless, the improvements of cooling rate, wind speed and average temperature were only 0.52%, 2.09% and 0.11%, respectively. The results demonstrated that the novel FTB ventilation proposed in the present study significantly improved ventilation efficiency and uniformity compared with conventional ventilation structures. The results presented herein provide theoretical support for the use and design of greenhouses suitable for China's special climate.

Synthesis of renewable diesel and jet fuel range alkanes using 2-methylfuran and cyclohexanone.

New solid acid catalysts were prepared by bisphenol A, paraformaldehyde and chlorosulfonic acid, and applied to hydroxylalkylation/alkylation (HAA) of 2-methylfuran (2-MF) and cyclohexanone. After optimizing the reaction conditions, the conversion of 2-MF reached 99% and the yield of 5,5'-(cyclohexane-1,1-diyl)bis(2-methylfuran) acquired 98%. The activity and catalytic efficiency were higher than those of Amberlyst 15 and Amberlyst 36 resins, which could be rationalized by high acid strength. At the same time, the catalysts were characterized by acid-base titration and FTIR. Hydrodeoxygenation (HDO) of HAA products of 2-methylfuran and cyclopentanone were processed on the Ni/SiO2 catalyst prepared by wet impregnation method to further convert into aviation kerosene, and the yield reached 93%.

Genetic analysis of three wild Eurasian eagle-owl subspecies, B. b. kiautschensis, B. b. ussuriensis, and B. b. tibetanus, in Chinese populations.

The Eurasian eagle-owl (Bubo bubo) is distributed throughout Asia and Europe and contains approximately twelve subspecies. Three subspecies, B. b. kiautschensis, B. b. ussuriensis, and B. b. tibetanus, are separately distributed in the refugia and plateau habitats of China. However, the genetics of these subspecies and populations have not been studied. Genetic differences were investigated among 32 individuals from six populations of these three B. bubo subspecies based on the mitochondrial genome. Low genetic diversity but high haplotype diversity was observed in these subspecies. The phylogenetic relationship of three B. bubo subspecies distributed in China was proven to be coordinated with geographic and environmental gradients. This study provides the first detailed insights into the mitochondrial genetic diversity of three Eurasian eagle-owl subspecies distributed in China and demonstrates the utility of the mitochondrial genome in intraspecific genetic population analyses of these eagle-owls.

Comparative Pharmacokinetic Profiles of Puerarin in Rat Plasma by UHPLC-MS/MS after Oral Administration of Pueraria lobata Extract and Pure Puerarin.

Puerarin is the main biologically active isoflavone in Pueraria lobata and has a wide range of biological activities. However, due to its poor water solubility and low oral bioavailability, its clinical applications are restricted. Compared with puerarin, the Pueraria lobata extract (PLE) has better water solubility, lower toxicity, and less side effects. In this study, the pharmacokinetics of orally administered puerarin (100 mg/kg) and PLE (763 mg/kg, equivalent to 100.0 mg/kg of puerarin) to rats was investigated by the UHPLC-MS/MS method. Results showed that when the rats were administered PLE, the area under the concentration-time curve from zero to infinity (AUC 0-inf ) dramatically increased from 219.83 ± 64.37 µg h/L to 462.62 ± 51.74 µg h/L (p < 0.01). The elimination half-time (t 1/2 ) also increased from 1.60 ± 0.38 h to 12.04 ± 5.10 h (p < 0.01). The maximum concentration (C max) of puerarin decreased from 101.64 ± 41.82 ng/mL to 48.64 ± 21.47 ng/mL (p < 0.01), and time to reach the maximum plasma concentration (T max) of puerarin decreased from 1.46 ± 1.08 h to 0.54 ± 0.30 h (p < 0.01). Results indicated that the pharmacokinetics of puerarin in Pueraria lobata may be dramatically different from pure puerarin in the plasma of rat, and oral bioavailability of puerarin may be increased when PLE was administrated to rats.

One-Pot Conversion of Lignin into Naphthenes Catalyzed by a Heterogeneous Rhenium Oxide-Modified Iridium Compound.

The direct transformation of lignin into fuels and chemicals remains a huge challenge because of the recalcitrant and complicated structure of lignin. In this study, rhenium oxide-modified iridium supported on SiO2 (Ir-ReOx /SiO2 ) is employed for the one-pot conversion of various lignin model compounds and lignin feedstocks into naphthenes. Up to 100 % yield of cyclohexane from model compounds and 44.3 % yield of naphthenes from lignin feedstocks are achieved. 2 D HSQC NMR spectroscopy before and after the reaction confirms the activity of Ir-ReOx /SiO2 in the cleavage of the C-O bonds and hydrodeoxygenation of the depolymerized products. H2 temperature-programmed reduction, temperature-programmed desorption of NH3 , IR spectroscopy of pyridine adsorption, X-ray photoelectron spectroscopy, X-ray absorption fine structure analysis, and control experiments reveal that a synergistic effect between Ir and ReOx in Ir-ReOx /SiO2 plays a crucial role in the high performance; ReOx is mainly responsible for the cleavage of C-O bonds, whereas Ir is responsible for hydrodeoxygenation and saturation of the benzene rings. This methodology opens up an energy-efficient route for the direct conversion of lignin into valuable naphthenes.

Emergence of Genetic Diversity and Multi-Drug Resistant Campylobacter jejuni From Wild Birds in Beijing, China.

Campylobacter jejuni (C. jejuni) is considered as an opportunistic zoonotic pathogen that may cause gastroenteritis in humans and other animals. Wild birds may be as potential vectors of C. jejuni around urban and suburban areas. Here, 520 samples were collected from 33 wild bird species in urban and suburban areas, Beijing. In total 57 C. jejuni were isolated from seven species. It was found that Nineteen (33.33%, 19/57) isolates were resistant to at least one of 11 antibiotics, especially streptomycin (36.84%) and four isolates resistant to all. Nineteen (33.33%, 19/57) isolates were multi-drug resistance. Multilocus sequence typing (MLST) analysis of the isolates showed that 36 different sequence types (STs) belonged to four Clonal complexes and unassigned. Twenty STs (55.56%) and six alleles among them were first detected. Virulence genes including flaA, cadF, and the cytolethal distending toxin (CDT) gene cluster, were detected in all isolates, but truncated cdt gene clusters only detected in the isolates from the crow, daurian jackdaw and silver pheasant. In conclusion, it was the first detection of C. jejuni involved truncated cdt gene clusters from the silver pheasant. These wild birds around urban and suburban areas may pose potential public health problems as reservoir vectors of C. jejuni.

Selective Cleavage of C-O Bonds in Lignin Catalyzed by Rhenium(VII) Oxide (Re2 O7 ).

Invited for this month's cover are the collaborating groups of Dr. Changzhi Li from Dalian Institute of Chemical Physics, China, and Dr. Lican Lu, Xiangtan University, China. The cover picture shows the harvest of a renewable supply of aromatic compounds accessible from lignin model compounds and lignin feedstocks through the selective Re2 O7 -catalyzed cleavage of lignin C-O bonds. This study paves the way towards the development of rhenium-based catalysts for the reductive valorization of realistic lignin materials in a controlled manner. Read the full text of the article at 10.1002/cplu.201700547.