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The objective of this study was to describe and classify common variations and compensation mechanisms in the sagittal alignment of the spine with lumbar degenerative disease.A total of 230 patients over 18 years old who underwent whole-spine X-rays to evaluate lower back pain were enrolled in this study. C7 slope, pelvic tilt (PT), sacral slope (SS), pelvic incidence (PI), thoracic kyphosis (TK), lumbar lordosis (LL), cervical lordosis (CL), thoracolumbar kyphosis (TLK), and sagittal vertical axis (SVA) were measured. Patients were divided into Group A (balance without compensation), B (balance with compensation), C (unbalance with compensation), and D (unbalance without compensation) according to spinopelvic balance and thoracic compensation.Group A had the largest LL, smallest PT, largest SS, and best clinical parameters of the four groups (p 0.001, p 0.001, p 0.001, p 0.001). The age increased gradually from Group B to Group D. Group B had an increased TK compared with Group A (p 0.001). Group C had an increased TK compared with Group A (p 0.001). Group D had an increased C7 slope compared with Group A (p = 0.022).This classification is shown four different regional and global alignments of the spine. Compensation took place to keep the balance of the spine. Classification types were consistent with age, compensation abilities, and clinical parameters. This classification potentially represents a valuable tool for comprehensive analysis of lumbar degenerative before surgical treatment considering sagittal balance.

Background Surgical treatment of severe thoracolumbar kyphosis (TLK) secondary to late osteoporotic vertebral compression fracture (OVCF) presents several challenges to spine surgeons. Proper selection of distal fusion level is an important issue in surgical planning to decrease the likelihood of distal mechanical complications. This study was designed to compare the clinical and radiographic outcomes in elderly patients suffering from severe TLK related with late OVCF between different distal fusion strategies and to recommend a superior distal fusion level for these patients. Methods A total of 57 consecutive subjects with a minimum follow-up of two years were retrospectively reviewed. TLK was defined as the hyperkyphosis with an apex below T10. Severe TLK was defined as the Cobb angle of kyphosis ≥60°. Patients fused to sagittal stable vertebra (SSV) were assigned to Group SSV, while those fused to the vertebra above and below SSV were assigned to Groups SSV- and SSV+, respectively. Bone cement was used to enhance pedicle screw fixation. Clinical and radiographic results were collected and compared between different groups. Results Deformity corrections and living quality improvements at the latest follow-up were superior in Group SSV than Group SSV- with shorter fusion levels, while to the equal extent with Group SSV+ with longer fusion levels. 7 cases of distal complications were observed in Group SSV-. Negatively balanced lowest instrumented vertebra was revealed to be the independent factor predicting distal complications. Patients’ satisfaction of their surgical management was greater in Group SSV than Group SSV- (83.2 ± 4.4% vs. 70.5 ± 10.9%, P = 0.024), while comparable with Groups SSV + SSV+ (84.8 ± 5.7%). Conclusions Fusion to SSV with cement-augmented pedicle screws could limit the development of distal junctional mechanical complications after surgical treatment for severe TLK secondary to late OVCF in elderly patients, while achieves satisfactory deformity correction with the preservation of necessary lumbar motility.

Background: Currently, ERAS for spinal surgery field is still in its beginnings, the major protocol lessons learned from other surgical specialties and lack of ERAS program for elderly patients (>70 years old). Geriatric patients has its own special characteristics resulting in more harmed by surgical stress. The enhanced recovery after surgery (ERAS) are designed to improving recovery after surgery and can result in substantial benefits in both clinical outcomes and cost-effectiveness. In the present study, we aimed to determine whether enhanced recovery after surgery (ERAS) significantly improved satisfaction and outcomes in elderly patients (>70 years old) with long-level lumbar fusion. Methods: A total of 154 patients were included, 72 in the ERAS group and 82 case-matched patients in the non-ERAS group. Data including demographic, comorbidity and surgical information were collected from electronic medical records. ERAS interventions were categorised as preoperative, intraoperative and postoperative. We also evaluated primary outcome, surgical complication and length of stay (LOS).Results: There were no statistically significant intergroup differences in regards to demographics, comorbidities, American Society of Anaesthesiologists (ASA) grade, or the number of fusion levels. There were also no differences between mean surgery time of intraoperative blood loss between the ERAS and non-ERAS groups. In addition, the mean preoperative Visual Analogue Score (VAS) for the back and legs and Oswestry Disability Index (ODI) score were not significantly different between the two groups. Overall, ERAS pathway compliance was 91.5%. There were no significant differences in the readmission and mortality rates at 30-day follow-up between the ERAS and non-ERAS groups. However, we observed a statistically significant decrease in the complications in the ERAS group(8 in the ERAS group versus 23 in the non-ERAS group, p=0.009) and LOS in the ERAS group (17.74±5.56 of ERAS group versus 22.13±12.21 in non-ERAS group, p=0.041). Multivariable linear regression showed that comorbidities (p=0.028) and implementation of ERAS program (p=0.002) were correlated with prolonged LOS. Multivariable logistic regression showed that comorbidities (p=0.029)， implementation of ERAS program (p=0.043) and preoperative VAS Back (p=0.046), were correlated with complications. Conclusions: This report describes the first ERAS protocol used in elderly patients after long-level lumbar fusion surgery. Our ERAS program is safe and could help decreases LOS and complication in elderly patients with long-level lumbar fusion.

Efficient electrocatalytic reduction of CO2 to value-added chemicals and fuels is a promising technology for mitigating energy shortage and pollution issues yet highly relay on the development of high-performance electrocatalysts. Herein, we develop an effective strategy to fabricate carbonized wood membrane (CW) decorated with AuPd alloy nanoparticles with tunable composition (termed as AuPd@CW) as self-supported electrodes for efficient electrocatalytic CO2 reduction. The uniformly distributed AuPd nanoparticles on wood matrix are first achieved through the in-situ reduction of metal cations by the lignin content in wood. Subsequently, two-step carbonization was employed to promote the alloying of AuPd nanoparticles and the formation of CW. The AuPd@CW membrane electrode features an integrated macroscopic structure with numerous open and aligned channels for rapid electron transfer and mass diffusion and well-dispersed AuPd alloy nanoparticles as active sites for the CO2 reduction. The optimal Au95Pd5@CW electrode affords a high selectivity for CO2 electroreduction with a maximum CO faradaic efficiency (FECO) of 82% at an overpotential of 0.49 V, much higher than those obtained on Au@CW and Pd@CW electrodes. The CO current density and FECO remain relatively stable during a 12 h electrolysis reaction. In addition, density functional theory (DFT) calculations reveal that alloying Au with Pd enables a balance between the formation of intermediate COOH* and the desorption of CO on the surface of AuPd nanoparticles, thus enhancing the selectivity of CO production. This work offers an effective strategy for the fabrication of bimetallic alloys supported on wood-based carbon membrane as a practical electrode for electrochemical energy conversion.

In this paper, the effects of the sulfur vacancy (VS) distribution in 2H–MoS2 monolayer on the H2 evolution mechanism and activity are researched by density functional theory (DFT) calculations. The calculation results reveal that the H2 generation on VS follows the Volmer-Heyrovsky mechanism with the Heyrovsky reaction as the rate determined step (RDS) with an energy barrier of 18.5 kcal/mol. When two VS are separated by one S atom, the H2 evolution on VS remains the Heyrovsky-step-determined Volmer-Heyrovsky mechanism and the RDS energy barrier increases to 20.0 kcal/mol. Removing adjacent S of VS causes that the Tafel-step-determined Volmer-Tafel mechanism works for HER and the barrier of RDS increases to 21.4 kcal/mol. Though the barriers of RDS ascend when the concentration of VS is enhanced by these two strategies, the Tafel step can take place at a lower potential and more VS are exposed. Therefore, two adjacent or next-near VS may obtain better H2 generation performance. Three adjacent or spaced out VS by one S may be less favorable for HER.

Developing and designing bifunctional electrocatalysts are very important for the production of hydrogen from water electrolysis. The reasonable interface modulation can effectively lead to the optimization of electronic configuration through the interface electron transfer in the heterostructures and thus resulting in the enhanced efficiency. In this work, self-supported and heterogeneous interface-rich Ni3S2@FeNi2S4@NF electrocatalyst for overall water splitting was designed and prepared through a controllable step-wise hydrothermal process. Density functional theory calculations suggest that heterogeneous interface formed between Ni3S2 and FeNi2S4 can optimize the Gibbs free energy for H* adsorption (ΔGH*). Benefiting from the open structure of the nanosheet arrays, the abundant heterogeneous interfaces in Ni3S2@FeNi2S4@NF composite, the positive synergistic effect between Ni3S2 and FeNi2S4, and the good conductivity of foamed nickel (NF) substrate, the optimized Ni3S2@FeNi2S4@NF nanoarray catalyst displayed excellent electrocatalytic activities, the overpotential is only 83 mV and 235 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) at 10 mA cm−2, respectively. Importantly, an alkaline electrolyser directly using the Ni3S2@FeNi2S4@NF as both the anode and cathode achieved an ultralow cell voltage of 1.46 V, accompanied by outstanding stability. The performance is better than that of most other transition-metal sulfides electrocatalysts. This work may provide a useful strategy for reasonably regulating heterogeneous interfaces to effectively improve the performance of materials, thus accelerating the practical application of transition-metal sulfides electrocatalysts for overall water splitting.

Development of low cost and high efficiency electrocatalysts for water splitting systems to produce renewable hydrogen energy is still a significant requirement. The engineering of nanostructure and element doping are effective methods to further improve the performance of catalysts. Nonmetal (such as N, P, S) doping has been extensively investigated, while the report of metal doping is relatively few. Herein, Fe doped CoP 1D hollow nanoneedles on carbon cloth (CC) are designed and fabricated by a hydrothermal method and subsequent phosphorization procedure. The conversion of Fe doped Co-hydroxide@CC to Fe–CoP can produce large number of nanopores, which are closely connected to each other, and form hollow structures within the nanoneedles. Benefiting from the effective Fe doping and the particular hollow nanoneedle structure, the obtained Fe–CoP@CC demonstrates good electrocatalytic activity for hydrogen evolution reaction (HER) both in alkaline and acidic solution, affording a current density of 10 mA cm−2 at overpotential of 49 mV and 80 mV, respectively. Moreover, the two-electrode electrolyzer with Fe–CoP@CC as both the cathode and anode catalyst achieve a current density of 10 mA cm−2 at a cell voltage of 1.58 V in 1.0 M KOH solution. The results illustrate that the obtained hollow Fe–CoP@CC nanoneedles can serve as an efficient catalyst for overall water splitting.

Background The lumbar spine displays its greatest mobility in ventral flexion, which is a potential risk factor for low back pain. The relative contribution of each segment to the complete flexion is denoted the spine rhythm, which is required to distinguish between normal and abnormal spinal profiles, and as well to calculate the spinal forces in musculoskeletal models. Nevertheless, different spine rhythms have been reported in literature and the effect of arm position has not been demonstrated. We therefore aimed to investigate the effects of different arm positions on spine rhythm during ventral flexion. Methods A nonradiologic back measurement device was used to determine the real-time back lordosis during ventral flexion while participants (10 male and 10 female without low back pain) held their arms at 6 different positions. Results During flexion with the arms naturally hanging down at both sides, the lumbar range of flexion was 52.6° ± 13.1°. Different arm positions displayed nonsignificant effect on lumbar range of flexion (P > 0.05). The middle and lower levels contributed more to the whole lumbar range of flexion than the upper level (P Conclusions The lumbar spine displayed greater flexion in the middle and lower levels and its flexion rhythm remained unchanged at different arm positions. These results strike importance to explore for more reasons explaining the different lumbar flexion rhythms reported in literature.

To our knowledge, laminectomy with fusion (LCF) and laminoplasty alone (LP) are both effective posterior surgical approaches for decompression of cervical spondylotic myelopathy (CSM). However, which one is suitable for patients has no standard answer. This study estimated whether the ratio of C2-C7 Cobb angle to T1 slope (CL/T1S) could be an indication of posterior surgical approach.We retrospectively reviewed 128 patients with at least 6 months of follow-up who underwent LCF or LP. Radiological measurements, including C2-C7 Cobb angle, decompressed Cobb angle, T1 slope, cervical sagittal vertical axis, and curvature index (CI), and clinical outcomes, including Japanese Orthopedic Association score and visual analogue scale were evaluated. ROC curve analysis was used to identify discriminative power of CL/T1S ratio to predict kyphotic deformity and severe lordosis loss. The t-test and Mann-Whitney U-test were used to evaluate the difference between LCF and LP. Kruskal-Wallis H - test and ANOVA were used to evaluate the difference among different ratio CL/T1S groups.The cervical lordosis decreased after LCF or LP (p 0.001, p 0.001, respectively). Based on ROC curve analysis, CL/T1S ratio had a good discriminative power to predict kyphotic deformity and severe lordosis loss (AUC = 0.70, AUC = 0.88, respectively). According to CI value changes, cervical lordosis losses in group LP were larger than that in group LCF (p = 0.006). However, there was no significant difference in CI changes of fair-ratio CL/T1S group between LCF and LP. For patients with low CL/T1S ratio or high CL/T1S ratio, CI changes in group LP were greater than that in group LCF (p = 0.037, p = 0.042, respectively).CL/T1S ratio could be an indication of posterior surgical approach. Compared with LP, LCF reduces postoperative cervical lordosis losses in low-ratio and high-ratio CL/T1S groups.

This study aimed to compare morphologic changes of deep paraspinal muscles at C4-7 in patients with C5-6 single-level cervical spondylotic myelopathy (CSM), and to evaluate the relationship between morphologic changes and the level of spinal cord compression.The study included 15 patients with C5-6 single-level CSM and 15 age- and sex-matched healthy subjects. Cross-sectional area (CSA) and functional CSA of the bilateral longus capitis (LCap), longus colli (LC), multifidus (MF), semispinalis cervicis (SSC), semispinalis capitis, splenius capitis, and splenius cervicis were measured on preoperative magnetic resonance images at C4-7, and calculated as ratios with respect to the corresponding vertebral body CSA.The mean maximum spinal cord compression was 22.30% in the CSM group. At the cranial level (C4-5), the CSM group had more fat infiltration in the MF and SSC (P0.05). At the spinal cord compression segment and caudal adjacent segment (C5-6 and C6-7), the degree of fat infiltration of all paravertebral muscles was aggravated, accompanied by atrophy of LCap, LC, and MF (P0.05). Compared between different levels, fat infiltration in the MF at C5-6 was greater than adjacent levels.In patients with C5-6 single-level CSM, fat infiltration and atrophy of deep paraspinal muscles, especially the Lcap, LC, and MF, mainly occurred in the level of spinal cord compression and caudal adjacent level. In the cranial adjacent segment, the degree of MF and SSC fat infiltration in patients with CSM was also aggravated. This may suggest that multiple mechanisms are involved in paraspinal muscles degeneration in CSM.

Tolerancing symbols play an important role in mechanical product drawings, and they directly determine the functions, mating properties, interchangeability and working life of geometrical products. A symbolic tolerancing callout containing a set of symbols represents a set of pre-ordered operations with attributes. It includes an amount of knowledge from the drawing and standard documents, which is often reconstructed manually by engineers. Thus, at the same time, a symbolic tolerancing callout makes it difficult for the end-user to understand and interpret these callouts manually. To this end, this study puts forward a tolerancing callout detection model via the use of off-the-shelf costumer-grade cameras on current mobile devices for extracting and recognizing tolerancing callout blocks and symbols in them intelligently. This model has four core components: image preprocessing, callout location and extraction, symbol and character segmentation, and deep learning-based symbol recognition. The image preprocessing component is developed to remove the interferences on the target technical drawings through the corresponding morphological methods. This study proposes a novel solution on callout block locations and extractions in callout intensive scenarios since the callout locations and extractions can directly affect the accuracy of symbol and character recognitions. Then, Huff Transform and improved projection methods have been devised to symbol and character segmentations. Finally, this study constructed a convolutional neural network (CNN) to train a symbol recognition model. The experimental results show that the proposed model gains applicability on intelligent callout extractions and the corresponding symbol recognitions.

To report the perioperative complication rates in elderly patients undergoing lumbar arthrodesis and to analyze the risk factors.Between September 2015 and June 2018, 215 patients aged ≥70 underwent posterior lumbar arthrodesis with pedicle screw fixation. Demographic data including age, gender, smoking status, body mass index (BMI) and preoperative comorbidities were collected. Operative records as the number of levels fused, estimated blood loss, time of surgery, and the occurrence of perioperative complications were reviewed. Risk factors of perioperative complications were determined by logistic regression analysis.The total perioperative complication rate in all patients was 30.2%, of which major complications occurred in 24 patients (11.2%) and minor complications occurred in 41 patients (19.1%). Two risk factors of perioperative complications (major or minor) were chosen: BMI (cutoff value 24.32) and surgical level (≥3). Lower surgical level (≥3) and smaller BMI were risk factors for perioperative minor complications, and major complication was affected only by surgical level (≥3).The risk factor of perioperative complication in elderly patients after lumbar arthrodesis was fusion segment (≥3), and BMI was a protective factor. Elderly patients with BMI24.32 are more likely to have perioperative complications after lumbar arthrodesis.

Fracability is a property that indicates how easy reservoir rocks can be fractured in hydraulic fracturing operations. It is a key parameter for fracturing design and evaluation. In order to utilize continuous logging data to predict fracability, synchronous tests of dynamic and static mechanical parameters of rocks under different confining pressures were conducted on 13 tight sandstone samples derived from the central Junggar Basin, China. A modified formula between dynamic and static mechanical parameters was established. Fracability of the tight reservoir in the Junggar Basin was then evaluated based on brittleness index, fracture toughness, and fracability index. The effectiveness of fracturing was analyzed combined with the oil testing curve after hydraulic fracturing. The results show that: (1) The distribution of oil-bearing formations in the studied area coincides well with stratum of higher fracability index. (2) The critical fracability index is determined to be 0.3, three formations are selected as fracturing candidates, and a thin mudstone interbed is identified in the oil-bearing formation. (3) Well testing curve verifies the reliability of the fracability evaluation method and the accuracy of the modified formula between dynamic and static mechanical parameters. This study provides useful information for improving fracturing operations of tight oil and gas reservoirs.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a highly desmoplastic tumor microenvironment (TME) consisting of abundant activated pancreatic stellate cells (PSCs). PSCs play a key role in the refractory responses of PDAC to immunotherapy and chemotherapy and deactivating PSCs into quiescence through vitamin D receptor (VDR) signaling activation is a promising strategy for PDAC treatment. We observed p62 loss in PSCs hindered the deactivation efficacy of VDR ligands, and hypothesized that reversing p62 levels by inhibiting autophagy processing, which is responsible for p62 loss, could sensitize PSCs toward VDR ligands. Herein, we constructed a PSC deactivator with dual functions of VDR activation and autophagy inhibition, utilizing a pH-buffering micelle (LBM) with an inherent ability to block autophagic flux to encapsulate calcipotriol (Cal), a VDR ligand. This Cal-loaded LBM (C-LBM) could efficiently reprogram PSCs, modulate the fibrotic TME, and alter immunosuppression. In combination with PD-1 antagonists and chemotherapy, C-LBM showed superior antitumor efficacy and significantly prolonged the survival of PDAC mice. These findings suggest that synergistic autophagy blockade and VDR signaling activation are promising therapeutic approaches to reprogram PSCs and improve the PDAC response to immunotherapy.

Pancreatic ductal adenocarcinoma (PDAC) is a dominantly (~95%) KRAS-mutant cancer that has extremely poor prognosis, in part this is due to its strong intrinsic resistance towards almost all therapeutic agents. PDAC relies heavily on KRAS-transformed metabolism, including enhanced macropinocytosis and catabolism of extracellular albumin, to maintain its proliferation and progression. However, it has yet to be validated that whether such transformed metabolism could be exploited for the drug delivery to open therapeutic windows of cytotoxic agents in KRAS-mutant PDAC. In this study, we attempt to answer this question by focusing on the impact of two critical regulators of albumin catabolism, KRAS and the neonatal Fc receptor (FcRn), on the sensitivity of PDAC to doxorubicin (DOX, a model cytotoxic agent) and albumin-conjugated doxorubicin (DOX-ALB). Using cell lines and cell-derived xenografts with different KRAS genotypes and FcRn levels, we demonstrated that KRAS-enhanced macropinocytosis and reduced FcRn expression sensitize PDAC to DOX-ALB but not free DOX. In both in vitro and in vivo comparsion, the DOX-ALB demonstrated ~10 times enlarged therapeutic window compared with free DOX, in PDAC with KRAS mutation and reduced FcRn level, two events appear to occur simultaneously in the investigated PDAC. In summary, we conclude that albumin conjugation is an exploitable drug delivery strategy that significantly opens the therapeutic windows of otherwise undevelopable anti-cancer agents for KRAS-mutant PDAC therapy, and creates a new landscape for clinical evaluation and future translation of such compounds.

To determine whether clinical characteristics and signal and morphologic changes on magnetic resonance (MR) images of the spinal cord (SC) are associated with surgical outcomes for cervical spondylotic myelopathy (CSM).A total of 113 consecutive patients with cervical myelopathy underwent cervical decompression surgery in our hospital from January 2015 to January 2018. All patients with preoperative MR images available for review were recruited for this study. Research data included patient sex, age, duration of symptoms, surgical approach, compression level, preoperative mJOA (modified Japanese Orthopaedic Association) score, postoperative mJOA recovery rate, and complications. Imaging data included signal changes on T2-weighted MRI images (grade and extension on sagittal images, four types of signal changes on axial images according to the Ax-CCM system), SC compression, transverse area of the SC, and compression ratio. The t-test, Mann-Whitney U-test, Kruskal-Wallis H - test, analysis of variance, and regression analysis were used to evaluate the effects of individual predictors on surgical outcomes.The study cohort included 85 males and 27 females with a mean age of 60.92 ± 8.93 years. The mean mJOA score improved from 10.24 ± 1.69 preoperatively to 15.11 ± 2.05 at the final follow-up (p 0.001). Patients in the poor outcome group were more likely to present with a longer duration of symptoms (p 0.001) and smaller transverse area of the SC (p 0.001). Bright T2-weighted high signal changes (T2HSCs), multisegmental high signal changes on sagittal MR images, and fuzzy focal T2HSCs on axial MR images were associated with a poor outcome (p0.001, p = 0.005, p 0.001, respectively). The maximum SC compression and compression ratio were not reliable predictors of surgical outcomes (p = 0.375, p = 0.055, respectively). The result of multivariate stepwise logistic regression showed that a longer duration of symptoms, multisegmental T2HSCs on sagittal MR images and fuzzy focal T2HSCs on axial MR images were significant risk factors of poor outcomes (p0.001, p = 0.049, p = 0.016, respectively).A longer duration of symptom, multisegmental T2HSCs on sagittal MR images, and fuzzy focal T2HSCs on axial MR images were highly predictive of a poor surgical outcome for CSM. Smaller transverse area of the SC and bright T2HSCs were also associated with the prognosis of CSM.

A novel approach to prepare graphene nanosheets was developed by exfoliating graphene oxide (GO) assisted with oxalic acid (H2C2O4). The expansion and reduction of GO were synchronously fulfilled through the decomposition of H2C2O4 impregnated into the interlayer of GO. The structure of the as-exfoliated graphene nanosheets were determined by a series of characterizations. The results showed that the as-exfoliated graphene nanosheets possessed ca. 10-layered thickness and the lower oxygen content. The mechanism was proposed that H2C2O4 played a role of the expansion–reduction associated effect in exfoliation.

This study evaluated survival outcomes of patients with intramedullary Grade II ependymomas and identify prognostic factors. Electronic searches of PubMed, EMBASE, OVID, the Cochrane Central Register of Controlled Trials were performed to identify trials according to the Cochrane Collaboration guidelines. The objects were intramedullary Grade II ependymoma according to 2007 WHO classification. Kaplan-Meier survival analysis with log-rank test was used to analyze progressive free survival (PFS) and overall survival (OS). Cox proportional hazard model was utilized for multivariate analysis with hazard ratio (HR) and 95% confidence interval (CI) calculated. P values

This work investigated the adsorption of Eosin Y (EY) on the surface of Ru4 and Pt4 clusters and the UV–vis adsorption of EY by the DFT and TD-DFT method, respectively. The relationship of adsorption action, adsorption energy and hydrogen production efficiency in EY-sensitized system were studied as well. It is proved that the enhancement in the interaction energy of key group in sensitizer and co-catalyst was an efficient method to improve hydrogen evolution performance. The TD-DFT calculation showed that the photoelectrons of excited state EY mainly focused on the upper surface of C5O ring with the COO− side. In the EY-Ru4 system, the maximum adsorption energy originated from the concurrent interaction of the COO− and C5O groups of EY with the Ru4 cluster was −237.8 kJ/mol, while in the EY-Pt4 system the maximum adsorption energy from the interaction between the C atom on C6 ring of EY and the Pt4 cluster was −230.5 kJ/mol. Compared with EY-Pt system, the dominating adsorption of EY on Ru was conducive to the quick transfer of photoelectron from EY to Ru. Therefore, the EY-Ru system exhibited higher hydrogen generation efficiency than the EY-Pt system.

The surface of self-made MoS2 nanosheets with five-layer structure was successively decorated by zinc borate (ZB) nanoparticles with coordination enhancement on the tribological performance and modified by three types of modifiers for improving dispersivity in oil. A series of characterizations determined the chemical modification and composite structure of the ZB/MoS2 nanocomposites. The tribological properties of the chemically capped ZB/MoS2 nanocomposites were extensively examined on a ball-on-ball wear tester. The average friction coefficient and average wear scar diameter of the OA-ZB/MoS2-based oil dropped by about 25.2% and 52.2%, and furthermore the extreme pressure performance increased by about 15.2% compared to oil.

One-dimensional MoS2 nanotubes were synthesized by using halloysite nanotubes (HNTs) as template and the thermolytical approach. The structure and morphology of MoS2 nanotubes were determined by a series of characterizations. The as-synthesized MoS2 nanotubes presented a hollow nanotubular structure with the pore diameter of 2.52 nm and the specific surface area of 89.34 m2/g. The formation mechanism of MoS2 nanotubes was proposed.

Due to existing the synergistic effect, the novel zinc borate/MoS2 nanocomposites (ZB/MoS2) were successfully fabricated by a liquid phase-based sonication. Subsequently, they were employed as additive to investigate tribological properties in grease. The structure, composition and morphology of the ZB/MoS2 as well as ZB/MoS2-based grease were determined by a series of characterizations, such as XRD, FTIR, Raman, TEM, SEM and EDX, indicating that the ZB nanoparticles were uniformly anchored on the surface of MoS2 nanosheets. The tribological properties of ZB/MoS2 nanocomposites were extensively studied through a four-ball testing machine. The experimental results indicated that the average friction coefficient and average wear scar diameter of the ZB/MoS2-based grease decreased by about 28.2% and 23.1%, and furthermore the extreme pressure performance increased by about 23.1% comparing to base grease. Finally, the antiwear mechanism was proposed by detecting worn surface.

In order to alleviate salt- and water-stress in plants, innovative and economically-feasible techniques are needed. In this study, pumice and biochar (made from willow at 350 °C) of different particle sizes (1.5-, 3-, and 6-cm O) were separately added at different rates (3, 6, and 12%, v/v basis) to a sandy soil and their effects on soil salinity and water retention were evaluated over time. Soils were drip irrigated with an artificial saline water under non-draining conditions. Pebbles applied at identical rates and sizes as pumice and biochar, were used as positive controls, whereas no amendment was the negative control. Treatments underwent 10 wetting and drying cycles at 35 °C at the end of which, the residual sandy soil (RS) was separated from the amendments. The electrical conductivity (EC) of RS followed the order pumice = negative control, with differences being significant at P 6% > 3%) was observed in the pumice when analysed separately from RS. Pumice and biochar treatments also retained more water in the soil after each drying cycle (significant at P

We investigated whether individual or combined additions of either pumice (PU) and/or algae (AL) to a sandy soil could alleviate the impact of irrigation with saline water on the growth of lucerne (Medicago sativa L.) under simulated semi-arid conditions. The study included six treatments that received saline water (6.4 dS m−1): T1 (sand – positive control), T2 (sand + 3% (v/v basis) PU), T3 (sand + 12% PU), T4 (sand + 3% PU + 2% AL), T5 (sand + 12% PU + 2% AL), T6 (sand + 2% AL). A seventh treatment was T7 (sand – negative control), to which deionised water was added. All treatments underwent 14 cycles of irrigation wetting and drying events (at 27 ± 1 °C/ 16 ± 1 °C day/night). At the end of the experiment and compared with the positive control (T1) (EC: 2.3 dS m−1; SAR: 21.8), the two treatments with the largest application rate of PU (T5 and T3) showed the largest (significant at P 0.05) reduction in soil EC, SAR, and water-extractable ions among those treatments receiving saline water (T1–T6). Lucerne in treatments T1–T6 always had a smaller dry weight (DW) biomass and relative growth rate (RGR) than the treatment receiving deionised water (T7) (DW: 2.29 g m−2; RGR: 0.073 mg g−1 d−1), but values for treatment T5 (DW: 1.69 g m−2; RGR: 0.06 mg g−1d−1) were significantly larger (P 0.05) than for treatments T1–T4 and T6 (DW 1.13 g m−2; RGR 0.056 mg g−1 d−1). Overall, the results obtained suggest that, if proven feasible at a field scale, the combined addition of PU (12%), by reducing salinity and contributing to water retention, and AL (2%), by adding nutrients and/or bioactive compounds, could be used to mitigate salt stress and improve plant growth in sandy soils under arid conditions.

In this paper, the reaction mechanism for N 2 O with CO on the surface of Ni 5 cluster was investigated by the B3LYP method of density functional theory (DFT). Ni atom of various species was calculated using B3LYP/ LANL2DZ basis set, and C, N, O atoms at B3LYP/6-31G ∗ level. In the temperature range of 100–1000 K, the statistical thermodynamics and Eyring transition state theory with Winger correction were used to study the kinetic characters of reaction. The calculation results indicated that the reaction of N 2 O with CO on Ni 5 cluster had two major reacting processes: (1) O atom first dissociated from N 2 O on Ni 5 cluster, and then reacted with CO on Ni 5 and (2) on the surface of Ni 5 catalyst, O atom of N 2 O direct interacted with C atom of CO, resulting into the dissociation of N 2 O and the form of CO 2 . The direct O extraction channel was the main channel due to its low potential energy and high rate constant.

Changes in soil organic matter (SOM) can affect food security, soil and water conservation, and climate change. However, the drivers of changes in SOM in paddy soils of China are not fully understood because the effects of agricultural management and environmental factors are studied separately. Soil, climate, terrain, and agricultural management data from 6 counties selected based on representative soil types and cropping systems in China were used in correlation analysis, analysis of variance, and cforest modeling to analyze the drivers of changes in SOM in paddy soils in the Middle and Lower Yangtze River Plain from 1980 to 2011. The aims of this study were to identify the main factors driving the changes in SOM and to quantitatively evaluate their individual impacts. Results showed that the paddy SOM stock in the study area increased by 12.5% at an average rate of 0.023 kg m−2 year−1 over the 31-year study period. As a result of long-term rice planting, agricultural management practices had a greater influence than soil properties, climate, and terrain. Among the major drivers, straw incorporation, the most influential driver, together with fertilization and tillage practices, significantly increased the accumulation of SOM, while an increase in temperature significantly influenced SOM decomposition. Therefore, to confront the challenge of rising temperatures, it is important to strengthen the positive effects of agricultural management. Rational fertilizer use for stabilizing grain production and crop straw incorporation are promising measures for potential carbon sequestration in this region.

Emodin is a natural anthraquinone derivative and contains abundant hydroxyl and carbonyl groups, which has high redox activity. As guest molecules, Emodin molecules were anchored on graphene sheet (GNS) by simple one-step reflux method. In the three-electrode system, the optimal composite electrode material (E@GNS) obtained the high specific capacitance of 338.9 F g−1 at 5 mV s−1 and excellent rate capability in 1 mol L−1 H2SO4. Finally, an asymmetric supercapacitor (ASC) was fabricated by using E@GNS as negative electrode and Caffeic acid non-covalently modified graphene hydrogel (GH-CFA) as positive electrode, respectively. The device achieved the energy density of 32.8 Wh kg−1 along with power density of 0.8 kW kg−1, and a light-emitting diode (LED) could be light up by two ASCs in series. To compare with the performance of ASC, we also assembled symmetric supercapacitor based on E@GNS, proving that the good matching of positive and negative electrode materials could make the supercapacitor exhibit the best capacitive performance.

In this paper, sodium polyacrylate (PAAS) was used as an assistant to markedly enhance the hydrogen generation efficiency of Eosin Y (EY) sensitized Pt photocatalyst. The molecule chain of polyacrylic acid ion adsorbed on Pt could gather EY on the surface of Pt nanoparticles, thereby enhancing the contact of EY and Pt and the utilization of photo-generated electrons generated by EY under visible light irradiation. Therefore, sodium polyacrylate stabilized Pt nanoparticles showed 3.25 times higher hydrogen generation activity than Pt-EY under the same conditions. The highest AQE of EY-PAAS 1 (m w > 30 million)-Pt system was 34.3% at 520 nm. This result provided a new approach for improving the hydrogen evolution efficiency of photocatalytic system.

This paper analyses the mechanism for the failure of primary support of a deep-buried tunnel whose side wall collapses during construction. The main focus is on discussion and comparison of the soil engineering aspects of the incident, and on the lessons that may be learnt from the case. Empirical and numerical analysis have been carried out for the collapse. The mechanisms of failure of tunnel are analyzed during tunnel excavation and the parameters of support are revised according to the results of analysis. Results have shown that the collapse of tunnel is mainly attributed to abundant joint fissures on surrounding soil. The changed support makes tunnel drive through the section of collapse successfully, and similar dangerous situation does not take place in the following construction.

By lyophilization of rifampicin (RIF) solution in TBA/water with various solvent compositions, uniform and amorphous rifampicin (RIF) microspheres were produced. Using 55% TBA solution, the obtained RIF microspheres have a mono-dispersive size distribution with diameters range from 1 to 3 μm. The RIF microspheres are found to be amorphous by X-ray diffraction, and are expected to dissolve much faster than the crystalline RIF upon inhalation. Mechanistic investigation revealed that the amorphous RIF microspheres were formed due to liquid-liquid phase separation (LLPS) occurred during the freezing of the TBA/water solution. We also observed that the RIF microspheres can be readily phagocytized by activated THP-1 cells within 15 min. The suitable size distribution, high solubility, and readiness for phagocytosis by macrophages, all suggest that the lyophilized amorphous RIF microspheres could be potentially used as an anti-tuberculosis inhalation therapy. In addition, similar process was used to lyophilize TBA/water solutions of several other drugs, including rifaximin, rifapentine, paclitaxel, and isoniazid. We found that for drugs with appropriate physiochemical properties, such as paclitaxel and rifaximin, mono-dispersive microspheres could be obtained as well, which demonstrated that freezing induced LLPS could be utilized as a novel particle engineering methodology to produce drug microspheres by lyophilization.

In this work, we developed a novel approach for few-layer graphene by employing Li+/Na+ co-intercalated exfoliation assisted by ultrasound method. The experiments were conducted under the ultrasonic power of 300 W and the frequency of 40 kHz without the participation of any organic solvent. The effect of Li+/Na+ proportion on the exfoliation of graphite was intensively investigated. The structure and morphology of the as-exfoliated graphene nanosheets (UGN) was determined by a series of characterizations. The results showed that the thicknesses of the as-exfoliated graphene nanosheets were about 2.38–2.56 nm (about 7–8 layers) at the optimal Li+/Na+ ratio. The potential application of the as-exfoliated graphene nanosheets as additive in grease was evaluated by four-ball friction tester. The results demonstrated that the antifriction and antiwear performances of the grease with 0.06 wt% graphene were significantly improved by 21.35% and 30.32% relative to pure grease, respectively. The friction mechanism was proposed by detecting the worn surfaces.

Organic molecules electrodes with high electrochemical reversibility has enormous potential in energy storage. Here, benz[a]anthracene-7, 12-quinone (BAQ) and 2, 5-dihydroxy-p-benzoquinone (DHBQ) are anchored on reduced graphene oxide (rGO) [BAQ (DHBQ)/rGO] by non-convent method to form the porous 3D dry aerogels. The optimal BAQ (DHBQ)/rGO electrode materials display capacitance all in excess of 400 F g−1 at current density of 1 A g−1 and an excellent rate capability in 1 M H2SO4 electrolyte. And BAQ/rGO and DHBQ/rGO are used respectively as the negative and positive electrode to fabricate the asymmetric supercapacitor (ASC), which achieves high energy density of 30.33 Wh kg−1 with power density of 802.9 W kg−1. Finally, 47 light-emitting diode (LED) bulbs aligned in a ‘NWNU’ shape are lit by two ASCs device in series, demonstrating its outstanding energy storage performance. Moreover, density functional theory (DFT) calculations are employed to understand the adsorption orientations, binding interactions and charge storage mechanism of BAQ on rGO surface, elucidating the superior electrochemical performance of the tested organic molecule electrode. In short, quinones non-covalently modified graphene is a promising and effective strategy for energy storage devices in future.

The conversion of cereal to vegetable represents a significant shift in land use in China, and it causes significant changes in soil properties. Most studies have only focused on chemical or biological properties; few have investigated soil structure. Soil structure, especially macropore space, is very important for plant growth because of its relation to important soil functions and processes, such as gas diffusion and water permeability. The objective of this study was to assess the effect of land use conversion from rice to vegetable on soil macropores (>50 μm) measured by computed tomography (CT) and to examine the relationships between CT-measured pore characteristics and soil chemical properties. By using space instead of time, we sampled three land uses – rice/wheat rotation (RWR), open-field vegetable (OFV) and plastic-greenhouse vegetable (PGV) – in a tilled and plow pan layer in a suburban area of Nanjing, China, and analyzed the basic physicochemical properties and CT-measured macropore characteristics. The results showed that the tilled layer soil had a significant response to the land use change. The macroporosity decreased from 11.5% under RWR to 8.0% under OFV and 5.8% under PGV, and the decreased portion consisted mainly of elongated large macropores (>1000 μm). In addition, the macropore morphology of vegetable fields also showed degradation, with a higher degree of anisotropy (DA) and lower fractal dimension (FD) and connectivity compared to those under RWR, but PGV experienced a higher degree of degradation than did OFV. This study also showed that soil structure degradation was significantly correlated with decreasing soil organic matter (SOM). Increasing the amount of organic fertilizer applied might improve the SOM content and therefore improve the soil structure. Based on the linear regression equation, adding 1 g of SOM per kilogram of soil can improve the macroporosity by 0.54 m3 m−3.

In this paper, the mechanisms of H2 evolution over the Mo-Edge of 2H-MoS2 with the unsaturated Mo (MoU) and S (SU) were investigated by the density functional theory. The calculations indicated that MoU was a key active site for H2 evolution. In the process of H2 evolution, the SU firstly absorbed H atom by the Volmer reaction, which caused the aggregation of electron on MoU, resulting in the barriers reduction of H transfer and H2 evolution on MoU. The formation of molybdenum hydride was the rate-limiting step. Compared to Mo-edge in 2H-MoS2, the barrier of key step for H2 evolution on Mo-edge with SU and MoU decreased obviously. This implied that the removal fractional S from the Mo-edge of 2H-MoS2 could enhance its H2 evolution activity and the electron trapping ability of active site for H2 evolution by the Volmer-Heyrovsky reaction might affect its activity.

Objectives We examined whether changes in diffusion tensor imaging (DTI) indices of the lumbosacral enlargement are similar to those at the cervical level, and correlate with clinical assessments in patients with cervical spondylotic myelopathy (CSM). Patients and methods Patients with CSM and healthy volunteers (40–42/group) received DTI scans at both lumbosacral enlargement and cervical spinal cord. Modified Japanese Orthopedic Association (mJOA) score was also recorded for those with CSM. The apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values of DTI in the two groups were compared. We also examined the correlation between DTI indices (ADC and FA) of the lumbosacral enlargement and those of the cervical spinal cord, and between DTI indices and mJOA in the CSM group. Results Compared with the values of healthy subjects, the ADC values of patients with CSM were significantly increased, and FA values were significantly decreased at both cervical spinal cord and lumbosacral enlargement. Changes in FA value of the cervical cord showed a positive correlation to those of the lumbosacral enlargement in the CSM group. Importantly, a linear correlation was detected between mJOA score and DTI indices (ADC and FA) of the cervical cord, as well as FA value of the lumbosacral enlargement in the CSM group. Conclusion DTI indices, especially FA, of the lumbosacral enlargement correlate with clinical assessments of patients with CSM, and hence may be useful for evaluating the severity of cervical cord injury.

In this work, we studied the modification of surface active site of Rh in RhSnxOy composite oxide co-catalyst by the addition of Sn for high efficient photocatalytic hydrogen evolution under visible light irradiation. The significant activity promotion was accomplished by the adjustment of Rh sites via Sn addition. After sensitized by Eosin Y (EY) dye, the RhSnxOy co-catalyst exhibited the apparent quantum efficiency (AQE) of 21.0% at 430 nm for hydrogen generation. Under optimized conditions, the highest hydrogen evolution rate of 1280.3 μmol h−1 (corresponding TON 64) over RhSnxOy co-catalyst was achieved, which was 8.3 times higher than that of Rh co-catalyst. Based on the XRD and XPS characterizations, Rh atom arrangement on the surface of RhSnxOy co-catalyst was confirmed. By adjusting Rh sites, it showed significantly different interaction between Rh atoms and Sn atoms, which led to more efficient excited charge separation and transfer from Rh atoms to Sn atoms with the amount of Sn increased, resulting in more effective photo-induced hydrogen generation.

Nickel tin composite oxides decorated graphene nanohybrid (NiSnxOy/G) cocatalyst was synthesized by in-situ chemical deposition and followed photoreduction reaction. The structure of NiSnxOy/G was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity of NiSnxOy/G sensitized by Eosin Y (EY) for hydrogen evolution were evaluated under visible light irradiation (λ ＞ 420 nm) using triethanolamine (TEOA) as sacrificial donor. The results indicated that the large amounts of NiSnxOy adhered on the surface of graphene sheet as active sites for hydrogen production. NiSnxOy/G showed higher photocatalytic performance than Ni/G under visible light irradiation (λ ≥ 420 nm) due to the higher photocatalytic activities of NiSnxOy and the electron transfer function of graphene sheets. The highest apparent quantum efficiency (AQE) of 36.2% over EY-NiSnxOy/G was achieved at 430 nm.