Hydrogen-Bond-Network Breakdown Boosts Selective CO2 Photoreduction by Suppressing H2 Evolution.

Conventional strategies for highly efficient and selective CO2 photoreduction focus on the design of catalysts and cocatalysts. In this study, we discover that hydrogen bond network breakdown in reaction system can suppress H2 evolution, thereby improving CO2 photoreduction performance. Photosensitive poly(ionic liquid)s are designed as photocatalysts owing to their strong hydrogen bonding with solvents. The hydrogen bond strength is tuned by solvent composition, thereby effectively regulating H2 evolution (from 0 to 12.6 mmol g-1 h-1). No H2 is detected after hydrogen bond network breakdown with trichloromethane or tetrachloromethane as additives. CO production rate and selectivity increase to 35.4 mmol g-1 h-1 and 98.9 % with trichloromethane, compared with 0.6 mmol g-1 h-1 and 26.2 %, respectively, without trichloromethane. Raman spectroscopy and theoretical calculations confirm that trichloromethane broke the systemic hydrogen bond network and subsequently suppressed H2 evolution. This hydrogen bond network breakdown strategy may be extended to other catalytic reactions involving H2 evolution.

Hydrogenation Reactions with Synergistic Catalysis of Pd single atoms and nanoparticles under Near-Ambient Conditions.

Due to the limited resources and high cost of noble metals, boosting their catalytic activities is highly desired in the current catalysis industry. Here, we report a synergetic catalyst, combining Pd2+ and Pd0 species in a nitrogen-doped porous carbons (NPC), which shows boosted catalytic activities in hydrogenation reactions of organic nitro compounds (nitrobenzene, 4-nitrophenol, 1-nitronaphthalene and 1-nitropropane) under near ambient conditions. This synergetic catalyst NPC-[Pd] was synthesized by partial reduction of a palladium-loaded NPC. The catalytic activities and selectivity of NPC-[Pd] for hydrogenation were enhanced significantly compared with those of NPC-Pd2+ or NPC-Pd0 nanoparticles. Theoretical calculations show that H2 preferentially dissociates on Pd nanoparticles, and then organic molecules (nitrobenzene) can be captured and react with the dissociated H atom on Pd2+ sites. Similar reaction procedure also occur on Pt or Rh. Hydrogenation of different aromatic compounds with different functional groups (naphthalene, 4-nitrochlorobenzene, benzaldehyde and acetophenone) confirmed the broad excellent catalytic activity of this synergistic catalyst.

Simulating Crystal Structure, Acidity, Proton Distribution, and IR Spectra of Acid Zeolite HSAPO-34: A High Accuracy Study.

It is a challenge to characterize the acid properties of microporous materials in either experiments or theory. This study presents the crystal structure, acid site, acid strength, proton siting, and IR spectra of HSAPO-34 from the SCAN + rVV10 method. The results indicate: the crystal structures of various acid sites of HSAPO-34 deviate from the space group of R3¯; the acid strength inferred from the DPE value likely decreases with the proton binding sites at O(2), O(4), O(1),and O(3), contrary to the stability order in view of the internal energy; the calculated ensemble-averaged DPE is about 1525 kJ/mol at 673.15 K; and the proton siting and the proton distribution are distinctly influenced by the temperature: at low temperatures, the proton is predominantly located at O(3), while it prefers O(2) at high temperatures, and the proton at O(4) assumedly has the least distribution at 273.15-773.15 K. In line with the neutron diffraction experiment, a correction factor of 0.979 is needed to correct for the calculated hydroxyl stretching vibration (ν(O-H)) of HSAPO-34. It seems that the SCAN meta-GGA method, compensating for some drawbacks of the GGA method, could provide satisfying results regarding the acid properties of HSAPO-34.

[Risk factors for neonatal asphyxia and establishment of a nomogram model for predicting neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture: a multicenter study]. / æ¹–åŒ—æ©æ–½åœŸå®¶æ—è‹—æ—è‡ªæ²»å·žæ–°ç”Ÿå„¿çª’æ¯å±é™©å› ç´ åˆ†æžåŠåˆ—çº¿å›¾é¢„æµ‹æ¨¡åž‹çš„æž„å»ºï¼šä¸€é¡¹å¤šä¸­å¿ƒç ”ç©¶.

OBJECTIVES: To investigate the risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture and establish a nomogram model for predicting the risk of neonatal asphyxia. METHODS: A retrospective study was conducted with 613 cases of neonatal asphyxia treated in 20 cooperative hospitals in Enshi Tujia and Miao Autonomous Prefecture from January to December 2019 as the asphyxia group, and 988 randomly selected non-asphyxia neonates born and admitted to the neonatology department of these hospitals during the same period as the control group. Univariate and multivariate analyses were used to identify risk factors for neonatal asphyxia. R software (4.2.2) was used to establish a nomogram model. Receiver operator characteristic curve, calibration curve, and decision curve analysis were used to assess the discrimination, calibration, and clinical usefulness of the model for predicting the risk of neonatal asphyxia, respectively. RESULTS: Multivariate logistic regression analysis showed that minority (Tujia), male sex, premature birth, congenital malformations, abnormal fetal position, intrauterine distress, maternal occupation as a farmer, education level below high school, fewer than 9 prenatal check-ups, threatened abortion, abnormal umbilical cord, abnormal amniotic fluid, placenta previa, abruptio placentae, emergency caesarean section, and assisted delivery were independent risk factors for neonatal asphyxia (P<0.05). The area under the curve of the model for predicting the risk of neonatal asphyxia based on these risk factors was 0.748 (95%CI: 0.723-0.772). The calibration curve indicated high accuracy of the model for predicting the risk of neonatal asphyxia. The decision curve analysis showed that the model could provide a higher net benefit for neonates at risk of asphyxia. CONCLUSIONS: The risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture are multifactorial, and the nomogram model based on these factors has good value in predicting the risk of neonatal asphyxia, which can help clinicians identify neonates at high risk of asphyxia early, and reduce the incidence of neonatal asphyxia.

Indication of the prognosis of pulmonary hypertension by using CMR function parameters.

OBJECTIVE: This study aimed to compare the cardiac function among different sub-types of pulmonary hypertension (PH) and to explore the independent predictors of major adverse cardiovascular events (MACE). METHODS: Eighty-seven PH patients diagnosed by right heart catheterization (RHC) were recruited. Patients underwent cardiac magnetic resonance (CMR) and RHC examination within 2 weeks. The CMR images were analyzed to calculate the cardiac functional parameters including right ventricle (RV) and left ventricle (LV) end-diastolic volume index (EDVI), end-systolic volume index (ESVI), stroke volume index (SVI), ejection fraction (EF), tricuspid annular plane systolic excursion (TAPSE), and myocardial mass (MM). The median follow-up time was 46.5 months (interquartile range: 26-65.5 months), and the endpoints were the occurrence of MACE. RESULTS: RVEDVI, LVEDVI, and LVESVI were higher in congenital heart disease-related PH (CHD-PH) than in other sub-types (p < 0.05). RVMM, RVSVI, and RVCI were highest in CHD-PH. There was no significant difference in the prognosis among different sub-types (p > 0.05). Comparing with the non-MACE group, RVEF, TAPSE, and LVSVI significantly decreased in the MACE group, while the RVESVI significantly increased (p < 0.05). TAPSE ≤ 15.65 mm and LVSVI ≤ 30.27 mL/m2 were significant independent predictors of prognosis in PH patients. CONCLUSION: CHD-PH had a higher RV function reserve but lowest LVEF comparing to other subgroups. TAPSE and LVSVI could contribute to the prediction of MACE in PH patients. KEY POINTS: • CMR imaging is a noninvasive and accurate tool to assess ventricular function. • CHD-PH had higher RV function reserve but lowest LVEF. • TAPSE and LVSVI could contribute to the prediction of MACE in PH patients.

The mechanism of ammonium bisulfate formation and decomposition over V/WTi catalysts for NH3-selective catalytic reduction at various temperatures.

In this study, the mechanism of ammonium bisulfate (ABS) formation and decomposition over V/WTi for the NH3-selective catalytic reduction (SCR) at various temperatures was deeply investigated. Bridged bidentate, chelating bidentate, and tridentate sulfates bound to TiO2 were formed as dominant intermediates at 200, 250, and 300 °C, respectively. These sulfates reacted with affinitive ammonium species to form ammonium (bi)sulfate species and also covered the active sites and embedded the VOSO4 intermediates, which resulted in an inferior intrinsic NH3-SCR conversion rate at 200 °C and 250 °C. At 300 °C, trace amounts of ABS on TiO2 presented no influence on the NH3-SCR performance. The electrons deviating towards sulfates through the bond between ABS and metal oxides (WO3 and TiO2) weakened the stability of ABS and lowered its decomposition temperature, whereas the vanadia species played the opposite role due to the sulfur species existing in an electron saturation state with the formation of the VOSO4 intermediate. The presence of NO + O2 could break the bonds inside ABS and it could react with the ammonium species originating from ABS, which pulls NH3 out of the ABS formation equilibrium and accelerates its decomposition and competitively inhibits its formation. Correspondingly, the faster NH3-SCR conversion rate and higher N2 selectivity improve the ABS poisoning resistance of the V/WTi catalyst at low temperatures.

Changes in liraglutide-induced body composition are related to modifications in plasma cardiac natriuretic peptides levels in obese type 2 diabetic patients.

BACKGROUND AND AIMS: Liraglutide treatment can improve glycemic control with a concomitant weight loss, but the underlying mechanism on weight loss is not completely understood. Cardiac natriuretic peptides (NPs) can resist body fat accumulation through increasing adipocytes lypolysis. In this study, we tested the hypothesis that liraglutide-induced weight loss was associated with increased plasma NPs concentrations. METHODS: Thirty-one outpatients with type 2 diabetes (T2D) treated with metformin and other oral antidiabetic drugs except for thiazolidinediones (TZDs) were subcutaneously administered with liraglutide for 12 weeks. Body composition, abdominal visceral adipose tissue areas (VAT) and subcutaneous adipose tissue areas (SAT) were assessed at pre- and post-treatment by dual-energy X-ray absorptiometry (DXA) scanning and abdominal computerized tomography (CT). Plasma atrial natriuretic peptides (ANP) and B-type ventricular natriuretic peptides (BNP) concentrations were tested by commercial ELISA Kit quantitatively. RESULTS: Following 12-week liraglutide treatment, body weight, waist circumference, total fat and lean mass, fat percentage, SAT and VAT areas were significantly reduced from baseline. Concurrently, plasma ANP and BNP levels were significantly increased following 12-week liraglutide treatment. There were significant correlations between the reductions in body compositions and the increases in both plasma ANP and BNP levels. CONCLUSIONS: There were significant correlations between increases in both plasma ANP and BNP levels and changes in liraglutide-induced body composition. Our data implied that increases in plasma NPs may add a novel dimension to explain how liraglutide induces weight loss.

A retrospective comparison of the modified tension band technique and the parallel titanium cannulated lag screw technique in transverse patella fracture.

OBJECTIVE: To compare efficacy between the modified tension band technique and the parallel titanium cannulated lag screw technique for the transverse patella fracture. METHODS: Seventy-two patients were retrospectively analyzed aged 22 to 79 years (mean, 55.6 years) with transverse patella fractures, among whom 37 patients underwent the modified tension band and 35 patients received the titanium cannulated lag screw. Patients were followed up for 1-3 years. We analyzed the difference of operation time, complications, fracture reduction, fracture healing time, and the Iowa score for knee function between both groups. RESULTS: In modified tension band group, five patients had skin irritation and seven suffered wire migration, two of whom required a second operation. In comparison, there were no complications in the titanium cannulated lag screw group, which also had a higher fracture reduction rate and less operation time. CONCLUSION: The parallel titanium cannulated lag screw technique has superior results and should be considered as an alternative method to treat transverse patella fracture.

Low-energy shock waves promote the cisplatin chemosensitivity of human osteosarcoma MNNG/HOS cells via the P2X7/Akt/mTOR pathway.

Background: The current dilemma of osteosarcoma treatment is the resistance of chemotherapeutic drugs after long-term usage, which also introduces life-threatening side effects. Methods and results: To minimize chemoresistance in osteosarcoma patients, the authors applied shock waves (SWs) to human osteosarcoma MNNG/HOS cells, then evaluated the cell viability and extracellular ATP levels, and further investigated the effect of SWs on cisplatin (DDP) cytotoxicity in MNNG/HOS cells. The authors' results showed that 400 SW pulses at 0.21 mJ/mm2 exhibited little influence on the MNNG/HOS cell viability. In addition, this SW condition significantly promoted the extracellular ATP release in MNNG/HOS cells. Importantly, low-energy SWs obviously increased Akt and mammalian target of rapamycin (mTOR) phosphorylation and activation in MNNG/HOS cells, which could be partially reversed in the presence of P2X7 siRNA. The authors also found that low-energy SWs strongly increased the DDP sensitivity of MNNG/HOS cells in the absence of P2X7. Conclusions: For the first time, the authors found that SW therapy reduced the DDP resistance of MNNG/HOS osteosarcoma cells when the ATP receptor P2X7 was downregulated. SW therapy may provide a novel treatment strategy for chemoresistant human osteosarcoma.

Machine learning aided design of single-atom alloy catalysts for methane cracking.

The process of CH4 cracking into H2 and carbon has gained wide attention for hydrogen production. However, traditional catalysis methods suffer rapid deactivation due to severe carbon deposition. In this study, we discover that effective CH4 cracking can be achieved at 450 °C over a Re/Ni single-atom alloy via ball milling. To explore single-atom alloy catalysis, we construct a library of 10,950 transition metal single-atom alloy surfaces and screen candidates based on C-H dissociation energy barriers predicted by a machine learning model. Experimental validation identifies Ir/Ni and Re/Ni as top performers. Notably, the non-noble metal Re/Ni achieves a hydrogen yield of 10.7 gH2 gcat-1 h-1 with 99.9% selectivity and 7.75% CH4 conversion at 450 °C, 1 atm. Here, we show the mechanical energy boosts CH4 conversion clearly and sustained CH4 cracking over 240 h is achieved, significantly surpassing other approaches in the literature.

The discrepancy of NH3 oxidation mechanism between SAPO-34 and Cu/SAPO-34.

The difference of NH3 oxidation mechanism over SAPO-34 and Cu-SAPO-34 was studied. XRD (X-ray diffraction), SEM (scanning electron microscopy) and H2-TPR (H2-temperature programmed desorption) were conducted to estimate the Cu species distribution. The quantity of individual Cu2+ ions escalated with the elevation of silicon content in the Cu/SAPO-34 catalysts, leading to an enhancement in the activity of the NH3-SCR (ammonia-selective catalytic reduction) process. This augmentation in activity can be attributed to the increased presence of isolated Cu2+ species, which are pivotal in facilitating the catalytic reaction. In addition, the kinetic test of NH3 oxidation indicated that the CuO species were the active sites for NH3 oxidation. Specifically, the strong structural Brønsted acid sites were the NH3 oxidation active sites over the SAPO-34 support, and the NH3 reacted with the O2 on the Brønsted acid sites to produce the NO mainly. While the NH3 oxidation mechanism over Cu/SAPO-34 consisted of two steps: firstly, NH3 reacted with O2 on CuO sites or residual Brønsted acid sites to form NO as the product; subsequently, the generated NO was reduced by NH3 into N2 on isolated Cu2+ sites. Simultaneously, the isolated Cu2+ sites might demonstrate a significant function in the NH3 oxidation process to form N2. The identification of active sites and corresponding mechanism could deepen the understanding of excellent performance of NH3-SCR over the Cu/SAPO-34 catalyst at high temperature.

Single-atom alloy Ir/Ni catalyst boosts CO2 methanation via mechanochemistry.

A new catalytic approach is pioneered to achieve CO2 methanation via a single atom alloy Ir/Ni catalyst using a ball-milling method. This Ir/Ni catalyst exhibits a TOFCH4 of 10244 h-1 and a 220 h lifetime at 350 °C without deactivation, illustrating excellent catalytic efficiency in the presence of mechanical energy.

Poly(ionic liquid)s for Photo-Driven CO2 Cycloaddition: Electron Donor-Acceptor Segments Matter.

CO2 cycloaddition with epoxides is a key catalytic procedure for CO2 utilization. Several metal-based catalysts with cocatalysts are developed for photo-driven CO2 cycloaddition, while facing difficulties in product purification and continuous reaction. Here, poly(ionic liquid)s are proposed as metal-free catalysts for photo-driven CO2 cycloaddition without cocatalysts. A series of poly(ionic liquid)s with donor-acceptor segments are fabricated and their photo-driven catalytic performance (conversion rate of 83.5% for glycidyl phenyl ether) outstrips (≈4.9 times) their thermal-driven catalytic performance (17.2%) at the same temperature. Mechanism studies confirm that photo-induced charge separation is promoted by the donor-acceptor segments and can accelerate the CO2 cycloaddition reaction. This work paves the way for the further use of poly(ionic liquid)s as catalysts in photo-driven CO2 cycloaddition.

Liquid Sunshine: Formic Acid.

"Liquid sunshine" is the conceptual green liquid fuel that is produced by a combination of solar energy, CO2, and H2O. Alcohols are commonly regarded as the preferred candidates for liquid sunshine because of their advantages of high energy density and extensive industrial applications. However, both the alcohol synthesis and H2 release processes require harsh reaction conditions, resulting in large external energy input. Unlike alcohols, the synthesis and dehydrogenation of formic acid (FA)/formate can be performed under mild conditions. Herein, we propose liquid sunshine FA/formate as a promising supplement to alcohol. First, we outline the vision of using FA/formate as liquid sunshine and discuss its feasibility. Then, we concentrate on the application of FA/formate as liquid organic hydrogen carrier and summarize the recent developments of CO2 hydrogenation to FA/formate and FA/formate dehydrogenation under mild conditions. Finally, we discuss the current applications, challenges, and opportunities surrounding the use of FA/formate as liquid sunshine.

Rational Design of Synergistic Structure Between Single-Atoms and Nanoparticles for CO2 Hydrogenation to Formate Under Ambient Conditions.

Single-atom catalysts (SACs) as the new frontier in heterogeneous catalysis have attracted increasing attention. However, the rational design of SACs with high catalytic activities for specified reactions still remains challenging. Herein, we report the rational design of a Pd1-PdNPs synergistic structure on 2,6-pyridinedicarbonitrile-derived covalent triazine framework (CTF) as an efficient active site for CO2 hydrogenation to formate under ambient conditions. Compared with the catalysts mainly comprising Pd1 and PdNPs, this hybrid catalyst presented significantly improved catalytic activity. By regulating the ratio of Pd1 to PdNPs, we obtained the optimal catalytic activity with a formate formation rate of 3.66 molHCOOM·molPd -1·h-1 under ambient conditions (30°C, 0.1 MPa). Moreover, as a heterogeneous catalyst, this hybrid catalyst is easily recovered and exhibits about a 20% decrease in the catalytic activity after five cycles. These findings are significant in elucidating new rational design principles for CO2 hydrogenation catalysts with superior activity and may open up the possibilities of converting CO2 under ambient conditions.

The Variation in the Diastolic Period with Interventricular Septal Displacement and Its Relation to the Right Ventricular Function in Pulmonary Hypertension: A Preliminary Cardiac Magnetic Resonance Study.

Background: Pulmonary hypertension (PH) is known to alter the biventricular shape and temporal phases of the cardiac cycle. The presence of interventricular septal (IVS) displacement has been associated with the severity of PH. There has been limited cardiac magnetic resonance (CMR) data regarding the temporal parameters of the cardiac cycle in PH. This study aimed to quantify the temporal changes in the cardiac cycle derived from CMR in PH patients with and without IVS displacement and sought to understand the mechanism of cardiac dysfunction in the cardiac cycle. Methods: Patients with PH who had CMR and right heart catheterization (RHC) examinations were included retrospectively. Patients were divided into an IVS non-displacement (IVSND) group and an IVS displacement (IVSD) group according to IVS morphology, as observed on short-axis cine CMR images. Additionally, age-matched healthy volunteers were included as the health control (HC). Temporal parameters, IVS displacement, ventricular volume and functional parameters were obtained by CMR, and pulmonary hemodynamics were obtained by RHC. The risk stratification of the PH patients was also graded according to the guidelines. Results: A total of 70 subjects were included, consisting of 33 IVSD patients, 15 IVSND patients, and 22 HC patients. In the IVSND group, only the right ventricle ejection fraction (RVEF) was decreased in the ventricular function, and no temporal change in the cardiac cycle was found. A prolonged isovolumetric relaxation time (IRT) and shortened filling time (FT) in both ventricles, along with biventricular dysfunction, were detected in the IVSD group (p < 0.001). The IRT of the right ventricle (IRTRV) and FT of the right ventricle (FTRV) in the PH patients were associated with pulmonary vascular resistance, right cardiac index, and IVS curvature, and the IRTRV was also associated with the RVEF in a multivariate regression analysis. A total of 90% of the PH patients in the IVSD group were stratified into intermediate- and high-risk categories, and they showed a prolonged IRTRV and a shortened FTRV. The IRTRV was also the predictor of the major cardiovascular events. Conclusions: The temporal changes in the cardiac cycle were related to IVS displacement and mainly impacted the diastolic period of the two ventricles in the PH patients. The IRT and FT changes may provide useful pathophysiological information on the progression of PH.

Epidemiological profile of 239 traumatic spinal cord injury cases over a period of 12 years in Tianjin, China.

STUDY DESIGN: Hospital-based retrospective review. OBJECTIVE: To describe the epidemiological characteristics and trends of traumatic spinal cord injury in Tianjin, China. SETTING: Tianjin Medical University General Hospital. METHODS: Medical records of 239 patients with traumatic spinal cord injury admitted to a general hospital from 1998 to 2009 were reviewed. Variables included gender, age, marital status, occupation, etiology, time of injury, level, and severity of injury. Epidemiological characteristics of different countries were compared. RESULTS: Over this period, the mean age of patients with traumatic spinal cord injury was 45.4 ± 14.1 years, and the male/female ratio was 4.6:1. In all, 86.2% were married. The leading cause was fall (52.3%), followed by motor vehicle collision (36.4%). The most common injury site was the cervical spinal cord, accounting for 82.0%. Incomplete tetraplegia made up for 59.4%, followed by complete tetraplegia (22.6%). Eight patients died after operation, six of whom died from respiratory complications. CONCLUSION: The results of this study are in accordance with that of most other developing countries; falls and motor vehicle collisions were the two leading causes, but the mean age was older. Percentage of the aged with traumatic spinal cord injury was increasing. The low-falls group tended to expand over this period. All these data indicated that the preventive programs should focus on the traffic accidents and falls, and more attention should be paid to the aged for the vulnerability to low fall.

(E)-Methyl N'-[(1H-indol-3-yl)methyl-idene]hydrazinecarboxyl-ate 0.25-hydrate.

The asymmetric unit of the title compound, C(11)H(11)N(3)O(2)·0.25H(2)O, contains two independent organic mol-ecules and a water mol-ecule, which lies on a twofold rotation axis. The side chains of the two mol-ecules have slightly different orientations, the C=N-N-C torsion angle being -163.03 (15)° in one and -177.52 (14)° in the other, with each adopting a trans configuration with respect to the C=N bond. In the crystal, mol-ecules are linked into chains extending along b by N-H⋯O, O-H⋯N and O-H⋯O hydrogen bonds and in addition, four inter-molecular C-H⋯π inter-actions are present.

(E)-Methyl N'-(2,4,5-trimeth-oxy-benzyl-idene)hydrazinecarboxyl-ate.

The title mol-ecule, C(12)H(16)N(2)O(5), adopts a trans configuration with respect to the C=N bond. In the crystal, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into chains in [001], and weak inter-molecular C-H⋯O inter-actions further link the chains into corrugated layers parallel to the bc plane.

(E)-Methyl N'-(3-hy-droxy-benzyl-idene)hydrazinecarboxyl-ate dihydrate.

The title compound, C(9)H(10)N(2)O(3)·2H(2)O, crystallizes with two organic mol-ecules and four water mol-ecules in the asymmetric unit. Both organic mol-ecules adopt a trans conformation with respect to the C=N bond and are close to planar [dihedral angles between the side chain and the aromatic ring = 9.34 (8) and 4.96 (8)°]. In the crystal, the components are linked into three-dimensional network by N-H⋯O and O-H⋯O hydrogen bonds.