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Background: Due to concomitant factors like frailty and comorbidity, super elderly (≥90 years) patients with hip fracture differ from patients aged 65-89 years in perioperative complications and mortality. The integrated management bundle referred to bundled application of multiple clinical measures. The aim of this study was to analyze effect of integrated management bundle on 1-year overall survival and perioperative outcomes in super elderly patients with hip fracture, with multidisciplinary management group serving as the control group.Methods: In this retrospective cohort study, super elderly patients with hip fracture were included from Jan 2017 to Nov 2020. Patients were retrospectively divided to multidisciplinary management group and integrated management bundle group. The primary outcome was 1- year overall survival, and the secondary outcome was perioperative outcomes. Kaplan-Meier methods was used to compare survival probability. Multivariable Cox's modeling was used to explain the effect of integrated bundle on 1-year overall survival adjusted for confounders. The perioperative outcomes including complications and in-hospital data of two groups were compared. The multivariable logistic regression was used to explain the effect of integrated bundle on the occurrence of perioperative complications adjusted for confounders. Prognostic factors related to survival was identified by multivariable Cox's regression analysis.Results: Ninety-seven patients comprised multidisciplinary management group, and 83 comprised integrated management bundle group. The Kaplan-Meier plots showed that the survival probability of integrated management bundle group was significantly better than multidisciplinary management group (HR:0.435, 95%CI:0.207-0.914, P = 0.039). Multivariable analysis after adjustment for confounders showed a 42.8% lower incidence of mortality integrated management bundle group than multidisciplinary management group (HR:0.428, 95%CI:0.186-0.986, P = 0.046). Incidence of hypoproteinemia, and electrolyte disturbance in integrated management bundle group was significantly lower than multidisciplinary management group (all P < 0.05). In addition, significant reduction was observed in length of stay (P < 0.05) in integrated management bundle group. Multivariable logistic regression showed integrated management bundle was independent protective factor of hypoproteinemia, and electrolyte disturbance. mECM score ≥ 6 and ASA score > 2 were independent risk factors of overall survival (HR: 1.940, 95%CI: 1.067-3.525,P = 0.030; HR: 2.281, 95%CI: 1.113-4.678,P = 0.024).Conclusions: The integrated management bundle improved 1-year overall survival and played positive effects in improving perioperative outcomes. It might be a more suitable management modality for super elderly patients with hip fracture. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to analyze the clinical characteristics of older fracture patients with chronic kidney disease (CKD) and to determine the risk factors of perioperative cardiovascular complications. Methods: We retrospectively reviewed clinical data of older fracture patients with CKD admitted to the Third Hospital of Hebei Medical University from January 2016 to October 2021. The data we collected included baseline characteristics and complications. We finally determined the risk factors of perioperative cardiovascular complications by using logistic regression. Results: We ended up enrolling 224 patients, and there were 91 (40.6%) males and 133 (59.4%) females, with a median age of 79 years. 80–84 years old was the age group with high incidence of fracture. The majority of fracture occurred indoors (130 cases, 58.0%) and morning (98 cases, 43.8%). Hip fracture was most common (183 cases, 81.7%), of which femoral neck fracture (101 cases, 45.0%) was the most prevalent. The most common comorbid condition was hypertension (171 cases, 76.3%), and anemia was the most common complication (148 cases, 66.1%). Age ≥ 80 years (OR = 2.023, 95% CI 1.110–3.688), previously combined with cardiovascular calcification (OR = 1.901, 95% CI 1.047–3.451) and admission hemoglobin level < 100 g/L (OR = 3.191, 95% CI 1.744–5.838) were independent risk factors of perioperative cardiovascular disease (CVD). Conclusion: It was especially necessary to enhance fracture prevention for CKD. Patients whose age older than 80, hemoglobin less than 100 g/L on admission and have previous cardiovascular calcification are more likely to develop perioperative CVD. Such patients require reasonable decisions during the perioperative period to avoid the occurrence of CVD. [ABSTRACT FROM AUTHOR]

Background: Patients with acute ischemic stroke (AIS) after hip fracture in the elderly have worse prognosis. We aimed to describe the characteristics and complications of hip fracture with AIS in the elderly.Methods: This cross-sectional study selected patients with hip fracture (age ≥65 years) from January 2018 to September 2020. The collected data included age, sex, fracture types, comorbidities. In above screened patients, we further collected cerebral infarction related information of AIS patients. The least absolute shrinkage and selection operator (LASSO) logistic regression was performed to identify the strongest predictors of AIS after hip fracture. Multivariate logistic regression analysis was conducted to find independent risk factors for AIS after hip fracture.Results: Sixty patients (mean age 79.7 years;female 56.7%) occurred AIS after hip fracture in 1577 cases. The most common infarction type was partial anterior circulation infarction (PACI) (70.0%). The majority of these infarction lesions were single (76.7%) and most infarction lesions(65.0%) were located in the left side. 81.7% of AIS patients had mild (Health stroke scale NIHSS <4) AIS. Older patients with AIS after hip fracture were more frequently complicated by hypertension(73.3%), prior stroke (46.7%), diabetes(35.0%) and were more likely to have hypoproteinemia(68.3%), electrolyte disorders ( 66.7%), anemia (65.0%), deep vein thrombosis (51.6%), pneumonia (46.6%),cardiac complications (45.0%). Combined with hypertension (OR 2.827, 95%CI 1.557-5.131) and male sex(OR 1.865, 95%CI 1.095-3.177) were associated with the increased risk of AIS after hip fracture.Conclusions: Older patients combined with hypertension are more likely to have AIS after hip fracture. For these patients, early preventions should be administered. AIS patients after hip fracture are prone to have multiple complications under traumatic stress, and we should enhance the management of these patients to reduce the stress and avoid occurrence of complications. [ABSTRACT FROM AUTHOR]

Introduction: This article mainly studies the risk factors for postoperative acute myocardial infarction (AMI) in elderly hip fracture patients combined with coronary heart disease (CHD), constructs a prediction model, and evaluates the prognosis of all the patients. Methods: This article retrospectively collected elderly patients with hip fracture and CHD who underwent hip fracture surgery at the Third Hospital of Hebei Medical University from January 2019 to December 2021. Demographic data, laboratory indicators, and imaging examination results were collected from the medical case system. The risk factors of postoperative AMI were determined by univariate and multivariate logistic regression, and a nomogram prediction model was established. The ROC curve, calibration curve and DCA decision curve were plotted by R language software. The patients in the training set were followed up for 2 years to evaluate their survival situation. Results: 1094 eligible patients were divided into a training set (n = 824 from January 1, 2019 to September 31, 2021) and a validation set (n = 270 from October 1, 2021 to December 31, 2022). In the training set, women accounted for 58.6%; The average age of the patients was 79.45 years old; The main type of fracture was intertrochanteric fracture. There were 64.7% patients taken B receptor blockers; A total of 166 (20.1%) patients underwent percutaneous coronary intervention (PCI); Hypertension accounted for 55.5%; 520 (63.1%) patients had a preoperative waiting time greater than 3 days; The average hemoglobin value upon admission was 101.36 g/L; The average intraoperative bleeding volume was 212.42 ml; The average surgical time was 2.5 ± 0.3 h; Reginal anesthesia accounted for 29.7%; 63 (68.5%) AMI patients had no obvious clinical symptoms; 68 (73.9%) AMI patients did not show ST-segment elevation in ECG; The risk factors of postoperative AMI were age, hemoglobin at admission, diabetes, chronic kidney disease, intraoperative bleeding, and reginal anesthesia. The AUC of the nomogram prediction model was 0.729. The AUC in the validation set was 0.783. Survival analysis showed a significant statistical difference in 2-year mortality between patients with AMI and without AMI, among all the patients with AMI, patients with ECG ST-segment elevation has higher mortality than patients without ECG ST-segment elevation. Conclusion: Our research results found that the incidence of postoperative AMI in elderly patients with hip fractures and CHD was 11.1%. Age, diabetes, hemoglobin at admission, regional anesthesia, chronic kidney disease, and intraoperative bleeding are risk factors. The AUC of the nomogram in training set is 0.729. The 2-year mortality rate of the patients with AMI is higher than that of patients without AMI. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study on the influence of miR-142-5p/212-5p mechanism on cardiac fibroblasts after myocardial infarction in the mouse model. Topics mentioned include the inhibition of the profileration and formation of collagen in cardiac fibroblasts, the effect of transforming growth factor-beta or angiotensin on cardiac fibroblasts, and the use of luciferase reporter assay.

A ring R is said to be strongly J n -clean if n is the least positive integer such that every element a is strongly J n -clean, that is, there exists an idempotent e such that e a = a e , a - e is a unit and e a n is in the Jacobson radical J(R). It is proved that strongly J n -clean ring is a strongly clean ring with stable range one. If R is an abelian ring (a ring in which all idempotents are central), then R is strongly J n -clean if and only if R / J(R) is strongly π -regular and idempotents lift modulo J(R). Some examples and basic properties of these rings are studied. Some criterions in terms of solvability of the characteristic equation are obtained for such a 2 × 2 matrix to be strongly J 2 -clean. [ABSTRACT FROM AUTHOR]

Photodetectors based on photoconductivity effect are usually driven by an external power source. A self-powered photodetector can be powered by incident light using the photovoltaic effect. Here, photoelectrochemical cells with periodically aligned ZnO/CdS nanowire arrays as photoanodes were fabricated and investigated for detecting UV and visible light. At zero bias, this self-powered UV-visible photodetector showed high responsivities of 35.4 and 23.2 mA/W for UV and visible light, a fast rise time of 0.18 s, and a decay time of 0.32 s. The spectral responses of the self-powered photodetectors based on ZnO/CdS nanowire arrays exhibited superior photoresponse in both UV and visible regions in comparison with ZnO nanowire film and ZnO nanowire arrays. The high photosensing performance originates from the excellent light trapping ability at broadband wavelengths and the high charge collection efficiency of the highly ordered ZnO/CdS nanowire arrays. The results indicate that the ZnO/CdS heterojunctions with periodic nanostructures provide a facile frame for UV-visible detecting applications. [ABSTRACT FROM AUTHOR]

Understanding the distribution of soil organic carbon and nitrogen (OC(N)) content, cation exchange capacity (CEC), and specific surface area (SSA) in different soil particle sizes is crucial for studying soil fertility and properties. In this study, we investigated the distribution characteristics of the OC(N), CECand SSA in different particles of yellow–brown soil under different methods. The result revealed that as the particle size decreased, the soil OC(N), SSA and CEC content gradually increase. The content of OC and ON different soil particles ranged from 1.50–28.16 g·kg−1 to 0.18–3.78 g·kg−1, respectively, and exhibited significant differences between different particles. We observed good linear relationships between OC and ON in different particle sizes of yellow–brown soil under different utilization methods, with correlation coefficients ranging from 0.86 to 0.98, reaching a very significant level (n = 12, p < 0.01). The ranges of SSA and CEC in different particles of the four soils were 0.30–94.70 m2·g−1 and 0.70–62.91 cmol·kg−1, respectively. Additionally, we found logarithmic relationships between SSA (CEC) and the equivalent diameter for the four soils, with correlation coefficients (r2) higher than 0.91. Furthermore, there was an extremely significant linear relationship between CEC and SSA of the four soils, with correlation coefficients (r2) of 0.92–0.97 (n = 12, p < 0.01). These results highlight the close relationship between soil particle size and soil OC(N), SSA, and CEC. The conclusions drawn from this study provide valuable data support and a theoretical basis for further understanding soil properties. [ABSTRACT FROM AUTHOR]

Insulating films such as sodium chloride (NaCl) are ideal platforms for studying single atoms and single molecules as decoupling layers. The NaCl dissolution process has been extensively studied, and has become an increasingly important scientific problem. However, the understanding of defect dynamics in the NaCl dissolution process at the atomic scale is still in the exploratory stage. Here we imaged the dissociation process of bilayer NaCl islands on an Au (111) surface at the atomic scale using a low-temperature scanning tunneling microscope. We found that water molecules preferentially combined with Na+, and formed Na+ hydrates accompanied by Na+ vacancy defects. First-principles calculations revealed a small diffusion barrier of Na+ hydrates, which contributed to the migration of Na+ vacancy defects. The defect density of Na+ vacancies increased with extension of the water exposure time, which resulted in a reduction of binding energy of the NaCl system. Calculations revealed that when the number of Na+ vacancy defects in a local area reached 35, the binding energy of the NaCl system dropped to zero. Then the NaCl in this area would completely dissociate. This work aids understanding of the NaCl dissolution process at the atomic level, and offers some references for the application and design of insulating films. [Display omitted] • Defect dynamics in the NaCl dissolution process are observed at the atomic scale. • Na + vacancy defects migrate randomly due to small diffusion barriers of Na + hydrates. • Defect density of Na + vacancies increases with extension of water exposure time. • Extension of water exposure time reduces binding energy of the NaCl system. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the neuroprotective effects of naringin on the memory impairment of hydrocortisone mice, and to elucidate the potential underlying molecular mechanisms. In the present study, a hydrocortisone model was constructed. Novel object recognition, Morris water maze and step-down tests were performed in order to assess the learning and memory abilities of mice. Hematoxylin and eosin staining was used to observe pathological changes in the hippocampus and hypothalamus. Transmission electron microscopy was used to observe the ultrastructural changes in the hippocampus. Immunohistochemistry was used to detect the expression of ERα and ERβ. Western blotting was performed to detect the expression of each protein in the relevant system. It was found that naringin can significantly improve cognitive, learning and memory dysfunction in mice with hydrocortisone memory impairment. In addition, naringin can exert neuroprotective effects through a variety of mechanisms, including amyloid β metabolism, Tau protein hyperphosphorylation, acetylcholinergic system, glutamate receptor system, oxidative stress and cell apoptosis. Naringin can also affect the expression of phosphorylated-P38/P38, indicating that the neuroprotective effect of naringin may also involve the MAPK/P38 pathway. The results of the present study concluded that naringin can effectively improve the cognitive abilities of mice with memory impairment and exert neuroprotective effects. Thus, naringin may be a promising target drug candidate for the treatment of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

The low-temperature scanning tunneling microscope and spectroscopy (STM/STS) are used to visualize superconducting states in the cleaved single crystal of 9% praseodymium-doped CaFe2As2 (Pr-Ca122) with Tc ≈ 30 K. The spectroscopy shows strong spatial variations in the density of states (DOS), and the superconducting map constructed from spectroscopy discloses a localized superconducting phase, as small as a single unit cell. The comparison of the spectra taken at 4.2 K and 22 K (below vs. close to the bulk superconducting transition temperature) from the exact same area confirms the superconducting behavior. Nanoscale superconducting states have been found near Pr dopants, which can be identified using dI/dV conductance maps at +300 mV. There is no correlation of the local superconductivity to the surface reconstruction domain and surface defects, which reflects its intrinsic bulk behavior. We, therefore, suggest that the local strain of Pr dopants is competing with defects induced local magnetic moments; this competition is responsible for the local superconducting states observed in this Fe-based filamentary superconductor. [ABSTRACT FROM AUTHOR]

Background: Medical and clinical question answering (QA) is highly concerned by researchers recently. Though there are remarkable advances in this field, the development in Chinese medical domain is relatively backward. It can be attributed to the difficulty of Chinese text processing and the lack of large-scale datasets. To bridge the gap, this paper introduces a Chinese medical QA dataset and proposes effective methods for the task.Methods: We first construct a large scale Chinese medical QA dataset. Then we leverage deep matching neural networks to capture semantic interaction between words in questions and answers. Considering that Chinese Word Segmentation (CWS) tools may fail to identify clinical terms, we design a module to merge the word segments and produce a new representation. It learns the common compositions of words or segments by using convolutional kernels and selects the strongest signals by windowed pooling.Results: The best performer among popular CWS tools on our dataset is found. In our experiments, deep matching models substantially outperform existing methods. Results also show that our proposed semantic clustered representation module improves the performance of models by up to 5.5% Precision at 1 and 4.9% Mean Average Precision.Conclusions: In this paper, we introduce a large scale Chinese medical QA dataset and cast the task into a semantic matching problem. We also compare different CWS tools and input units. Among the two state-of-the-art deep matching neural networks, MatchPyramid performs better. Results also show the effectiveness of the proposed semantic clustered representation module. [ABSTRACT FROM AUTHOR]

We previously identified a lipopeptide, EK1C4, by linking cholesterol to EK1, a pan-CoV fusion inhibitory peptide via a polyethylene glycol (PEG) linker, which showed potent pan-CoV fusion inhibitory activity. However, PEG can elicit antibodies to PEG in vivo, which will attenuate its antiviral activity. Therefore, we designed and synthesized a dePEGylated lipopeptide, EKL1C, by replacing the PEG linker in EK1C4 with a short peptide. Similar to EK1C4, EKL1C displayed potent inhibitory activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other coronaviruses. In this study, we found that EKL1C also exhibited broad-spectrum fusion inhibitory activity against human immunodeficiency virus type 1 (HIV-1) infection by interacting with the N-terminal heptad repeat 1 (HR1) of viral gp41 to block six-helix bundle (6-HB) formation. These results suggest that HR1 is a common target for the development of broad-spectrum viral fusion inhibitors and EKL1C has potential clinical application as a candidate therapeutic or preventive agent against infection by coronavirus, HIV-1, and possibly other class I enveloped viruses. [ABSTRACT FROM AUTHOR]

Group-IIIA metal-monochalcogenides with the enticing properties have attracted tremendous attention across various scientific disciplines. With the aim to satisfy the multiple demands of device applications, here we report a design framework on GaSe monolayer in an effort to tune the electronic and magnetic properties through a dual modulation of vacancy doping and electric field. A half-metallicity with a 100% spin polarization is generated in a Ga vacancy doped GaSe monolayer due to the nonbonding 4 p electronic orbital of the surrounding Se atoms. The stability of magnetic moment is found to be determined by the direction of applied electric field. A switchable magnetic configuration in Ga vacancy doped GaSe monolayer is achieved under a critical electric field of 0.6 V/Å. Electric field induces redistribution of the electronic states. Finally, charge transfers are found to be responsible for the controllable magnetic structure in this system. The magnetic modulation on GaSe monolayer in this work offers some references for the design and fabrication of tunable two-dimensional spintronic device. [ABSTRACT FROM AUTHOR]

While the miniaturization and motility of artificial nanomotors made them popular tools for exploring novel and innovative biomedical cancer treatment strategies, the integration of multiple functions on the small motor bodies is key to achieve further progress but remains unresolved. Here, we propose a dual-source powered Janus nanomotor whose composition integrates multiple photo-theranostic functions such as surface-enhanced Raman scattering (SERS) sensing, fluorescence imaging/photoacoustic imaging (PAI), photodynamic therapy (PDT), and photothermal therapy (PTT). This nanomotor can be fabricated by sputtering a thin gold layer onto one side of mesoporous silica (mSiO 2) combined with surface modification by photo-sensitizer, Raman reporter, and catalase. Upon illumination with 808 nm near-infrared light, the half-coated gold nanoshell serves as PAI/PTT agent, and by upconverting NIR to visible light, the pre-loaded photosensitizer can be excited by the upconverted light of UCNPs to convert the dissolved oxygen (O 2) into reactive oxygen species for efficient PDT. Furthermore, ratiometric SERS signal can be captured to quantitatively detect the tumor marker, H 2 O 2 , in cellular microenvironments. The immobilized catalase as a nano-engine can catalyze endogenous H 2 O 2 to O 2. This function not only improves the hypoxic tumor microenvironment and therefore enhances PDT efficiency, but also provides a thrust force for deep penetration. As a proof of concept for the in vivo trial we performed cancer photo-theranostics where our nanomotors successfully treated a mouse breast tumor in a subcutaneous tumor model. The results are promising and encourage the use of an integrated nanomotor platform that could be further developed into a photo-theranostic agent for superficial cancer treatment. [ABSTRACT FROM AUTHOR]

Pharmaceuticals and Personal Care Products (PPCPs) are inadvertently released into the aquatic environment, causing detrimental effects on aquatic ecosystem. There is an urgent need of an in-deep investigation on contamination information of PPCPs in aquatic environment as well as the ecological risks to the aquatic ecosystem. This study was carried out in Lipu River basin, China, to investigate the distribution pattern and ecological risks of PPCPs. Results showed that PPCPs pollution is ubiquitous, 29 out of 30 targeted PPCPs were detected in Lipu River. Fourteen PPCPs were detected with a frequency of 100% in all water samples, and ten PPCPs were detected with a frequency of more than 80%. The cumulated PPCPs concentrations ranged from 33.30 ng/L to 99.60 ng/L, with a median value of 47.20 ng/L in Lipu River. Caffeine, flumequine, nifedipine, and lomefloxacin were the predominant PPCPs in study area. Caffeine showed high ecological risk, five and seven individual PPCP showed medium and low ecological risk to algae. [Display omitted] • 29 out of 30 targeted PPCPs were detected in the Lipu River basin. • CAF and FQ are the main PPCP compounds. • CAF exhibited high ecological risk to algae. • Rural area showed severe PPCPs contamination. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel 3DOM Ag 2 S-CoO x /NC had been developed by integrating ultrafine Ag 2 S QDs on the surface of 3DOM CoO x /NC. • The 3DOM Ag 2 S-CoO x /NC composite exhibited remarkable performances for the photocatalytic conversion of CO 2 and H 2 O vapor to fuels. • There were dual Z-scheme charge transfer pathways in the 3DOM Ag 2 S-CoO x /NC. • The key role of Ag 2 S QDs was served as an auxiliary to improve the electronic structure and facilitate adsorption/activation capacity of CO 2 and H 2 O. • The multiple photocatalytic mechanisms of CO 2 reduction were further identified by in situ DRIFTS. Rational design of advanced architectural photocatalysts with efficient separation and transfer of photoinduced charge carriers, and well solar light absorption ability is of critical significance for solar energy utilization and CO 2 -to-fuel conversion. Herein, a novel three-dimensional (3D) ordered hollow-wall hybrid composite (3DOM Ag 2 S-CoO x /NC) has been developed by integrating ultrafine Ag 2 S quantum dots (QDs) on the surface of metal–organic frameworks (MOFs)-derived hierarchically ordered macroporous nitrogen-doped carbon skeletons with implanted CoO x nanoclusters (3DOM CoO x /NC). Compared with pristine 3DOM CoO x /NC and traditional ZIF-67-derived CoO x /NC, the constructed 3DOM Ag 2 S-CoO x /NC composite exhibits remarkable performances toward the photocatalytic conversion of CO 2 and H 2 O vapor without any sacrifice reagents to fuels (CO-66.00 μmol g−1h−1, CH 4 -1.21 μmol g−1h−1 and C 2 H 4 -2.33 μmol g−1h−1) and a higher C 2 H 4 selectivity (16.47%) in the gas–solid system under light irradiation (λ > 420 nm). Impressively, dual Z-scheme charge transfer pathways in the 3DOM Ag 2 S-CoO x /NC can provide good channels for boosting electron transfer and charge separation. Experimental characterizations combined with density functional theory (DFT) calculations further elucidate that the key role of Ag 2 S QDs is served as an auxiliary in the 3DOM Ag 2 S-CoO x /NC catalyst to improve the electronic structure and further facilitate adsorption/activation capacity of CO 2 and H 2 O. Moreover, the multiple photocatalytic mechanisms including related key intermediates and conversion process of CO 2 molecules are further identified by in-situ diffuse reflectance infrared fourier transform spectra (DRIFTS). This innovation provides a novel strategy to design well-designed hierarchically porous hybrid structures for photocatalytic CO 2 reduction to high-value fuels. [ABSTRACT FROM AUTHOR]

[Display omitted] • A strategy that using AMP as a gelatinous product inhibitor in NNAs was proposed. • AMP-regulated NAAs did not yield insoluble gelatinous products during CO 2 absorption. • AMP-regulated NAAs featured good CO 2 capture performance. • CO 2 absorption mechanism was studied based on 13C NMR and theoretical calculations. • The inhibitory mechanism of AMP on the formation of gelatinous products was clarified. Diamines or polyamines with two or more amino groups are suitable for formulating non-aqueous absorbents (NAAs) with high CO 2 loading capacity and low regeneration energy consumption. However, these two types of amines in NAAs are prone to produce insoluble gelatinous products after absorbing CO 2 , resulting in difficult operation of the CO 2 capture system. In this study, by using 2-amino-2-methyl-1-propanol (AMP) as an inhibitor, the insoluble gelatinous products of the aminoethylethanolamine (AEEA)-N-methyl-2-pyrrolidone (NMP) (A-A-N) and 3-(methylamino)propylamine (MAPA)-NMP (M-A-N) NAAs were successfully eliminated. The experimental results showed that the AMP-regulated NAAs possessed a high absorption rate, high CO 2 loading capacity, excellent desorption efficiency, and stable recyclability. The reaction mechanism of CO 2 absorption and the inhibitory mechanism of AMP on the formation of gelatinous products were comprehensively elucidated. Taking the A-A-N system as a representative, AEEA reacted with CO 2 to form zwitterionic protonated carbamate species (AEEACO 2 − (P) H+ (S)), which tended to self-aggregate via hydrogen-bond interaction, resulting in the formation of insoluble gelatinous products. With the introduction of AMP, the AMP-derived products could combine easily with AEEACO 2 − (P) H+ (S) via strong electrostatic attraction to form ion pairs, preventing the AEEACO 2 − (P) H+ (S) molecules from self-aggregating to form insoluble gelatinous products. The regeneration heat duty of the A-A-N system was 1.89 GJ∙ton−1 CO 2 , which was 49.9 % lower than that of the benchmark 30 wt% MEA. Overall, introducing AMP as a gelatinous product inhibitor was beneficial for the development of NNAs with high CO 2 absorption capacity and low-energy consumption. [ABSTRACT FROM AUTHOR]

Abstract: Based on the systematic study of electropolishing process, an improved tungsten STM probe fabrication technique has been presented. The proper combination of pulse current and the electrolyte concentration is explored for the elimination of impurities and achieves high quality probes with ultra-smooth surfaces. An optimized immersion depth of tungsten wire in electrolyte is proposed for the purpose of realizing the probe with sharp apex as well as high aspect ratio structure. A control strategy for determining the power-off instant during the procedure of electropolishing is developed which will facilitate the fabrication of probe with exponential contour as well as ultrasharp tip. The proposed technique and process are experimentally confirmed to have advantages for the STM probe fabrication of the stabilized stylus contour, typically with apex radius of 30nm and the yield rate reaches as high as 85%. [Copyright &y& Elsevier]

The role of silver localized surface plasmons (LSPs) on the luminescence of a Si(111)-(7 × 7) surface has been investigated by scanning tunneling microscopy (STM) with a silver tip at 77 K. On a bare Si(111)-(7 × 7) surface, a characteristic peak at 1.85 eV dominates the STM-induced luminescence spectrum, although the luminescence intensity is extremely weak. Once Ag atoms are deposited onto the Si surface to form islands with a few atomic layers, it is found that the intensity of the characteristic peak from the Si surface underneath the Ag islands is significantly enhanced by about one order. In addition to the luminescence from the Si surface, light emission originating from the irradiation decay of the Ag plasmons is also detected. Such great enhancement of the luminescence from the Si surface is attributed to the strong coupling between the surface states of the Si and the LSPs of the Ag islands. [ABSTRACT FROM AUTHOR]

Background: Plasmid-mediated mechanisms of drug resistance accelerate the spread of polymyxin resistance, leaving clinicians with few or no antibacterial options for the treatment of infections caused by MDR bacteria, especially carbapenemase-producing strains.Objectives: To evaluate the associations among promoter sequence variation, mcr-1 expression, host factors and levels of colistin resistance and to propose antisense agents such as peptide nucleic acids (PNAs) targeting mcr-1 as a tool to restore colistin susceptibility through modulation of MCR-1 expression in Escherichia coli.Methods: A β-galactosidase assay was performed to study mcr-1 promoter activity. Quantitative real-time PCR and western blot assays were used to identify the expression level of MCR-1 in WT strains and transformants. Three PNAs targeting different regions of mcr-1 were designed and synthesized to determine whether they can effectively inhibit MCR-1 expression. MIC was measured to test colistin susceptibility in the presence or absence of PNA-1 in mcr-1-carrying E. coli.Results: Variation in the mcr-1 promoter sequence and host species affect promoter activity, MCR-1 expression levels and colistin MICs. One PNA targeting the ribosome-binding site fully inhibited the expression of mcr-1 at a concentration of 4 μM, resulting in significantly increased susceptibility to colistin. The MIC90 of colistin decreased from 8 to 2 mg/L (P < 0.05) in the presence of 4 μM PNA.Conclusions: These findings suggest that the antisense approach is a possible strategy to combat mcr-1-mediated resistance as well as other causes of emerging global resistance. [ABSTRACT FROM AUTHOR]

In this study, a novel spray drying-assisted self-assembly (SDAS) technology was proposed to prepare submicron elemental explosives with good morphology, uniform dispersion, and low sensitivity and spherical submicron RDX, HMX, and CL-20 particles without soft agglomeration were fabricated via such a method. Structural characterizations and thermal stability of the composites were systematically studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimeter (DSC). Moreover, safety performance was analyzed by qualitative testing of impact sensitivity and friction sensitivity. The XRD analysis demonstrated that HMX and CL-20 refined by SDAS maintained the crystal structure of β-HMX and ε-CL-20 before and after refinement, whereas the HMX crystal structure after spray recrystallization refinement was transformed from β-HMX to α-HMX. The DSC results indicated that the thermal decomposition peak temperature of the three particles refined by the SDAS technology had a minimum advancement, and the thermal stability of the particles was relatively superior. More importantly, the H50 of the RDX, HMX, and CL-20 refined by this novel method was increased to 48.3 cm, 44.6 cm, and 31.1 cm, and the probability of friction explosion was decreased to 62%, 62%, and 80%, respectively, thus significantly improving the safety performance as compared with the sample refined by spray recrystallization. [ABSTRACT FROM AUTHOR]

[Display omitted] • A ternary MOF-on-MOF strategy was introduced to synthesize the core double-shell FeS x @ZnS@CoS x catalyst. • FeS x @ZnS@CoS x exhibited the excellent catalytic activity for the CO 2 photoreduction. • FeS x @ZnS@CoS x structure with dual type II heterojunctions improved the separation of electron-hole pairs. • The superstructure of CoS x species provided abundant active sites and broadened light absorption capacity. The construction of core–shell structures derived from metal-organic framework (MOF) precursors is considered as a promising strategy for promoting photocatalytic CO 2 reduction. Herein, a core double-shell structure catalyst (FeS x @ZnS@CoS x) has been rationally fabricated by ternary MOF-on-MOF synthetic strategies combined with subsequent sulfidation treatments. The obtained FeS x @ZnS@CoS x exhibited appealing activity for photocatalytic CO 2 conversion with H 2 O vapor, affording a high CO generation rate of 69.90 μmol g−1 h−1 and CH 4 generation rate of 2.01 μmol g−1 h−1. The outstanding performances could benefit from the distinctive core double-shell structure, which effectively formed dual type II charge transfer channels to improve the separation and migration of photogenerated carriers. Besides, the superstructure of CoS x species can provide abundant active sites to increase CO 2 adsorption and meanwhile enhance the absorption spectrum in the visible light region, facilitating the CO 2 conversion. The possible reduction pathways and key reaction intermediates were revealed by in situ DRIFTS results. This work offers a feasible ternary MOFs strategy to develop multi core–shell structures for high photocatalytic performance. [ABSTRACT FROM AUTHOR]

Route topography is an important test boundary of real driving emission (RDE) tests. However, the RDE test boundaries, such as atmospheric environment, driver behavior, route topography, and traffic congestion, are random, uncertain, and completely coupled. It is difficult to know to what extent route topography can determine on-road emissions, especially in a region with hilly topography. In this regard, the neural network predictor importance algorithms were proposed to measure the importance of the route topography test boundary. Based on tens of thousands of data window samples from the RDE tests in Chongqing, factor analysis was performed to reduce the data dimensionality and eliminate information overlap, and neural network models were established to predict pollutant emissions and calculate the relative importance of input variables. The results show that route topography is comparable to trip dynamics for on-road emissions but the importance of the route topography test boundary is not fully appreciated in the existing RDE regulation, making mountain cities suffer from severe vehicle emissions that are not effectively controlled. • Route topography impact on vehicle emissions was explored by neural network models. • Predictor importance algorithms using sensitivity analysis were introduced. • Data dimensions were downsized to eliminate the overlap of trip dynamic variables. • Data windows were treated as trip sections to expand the sample space significantly. • Route topography test boundary requires revision in the RDE test regulation. [ABSTRACT FROM AUTHOR]

The performance of constructed wetland (CWs) systems should improve through the electrochemistry of microorganisms, with the help of conductive fillers. To explore the strengthening mechanism of the CWs, three comparative experiments, including Co CWs (electro-conductive materials coke as filler), Co-P CWs (coke as filler with pickerel weed (Pontederia cordata L)), and QS-P CWs (quartz sand as filler with pickerel weed (Pontederia cordata L)), were tested to investigate the influence of the clogging process on the purification capacity from the electrochemical characteristics and the community of microorganisms in domestic sewage. The results showed that coke, as an electro-conductive filler, had the best organic removal and high electric output, even with solid particle accumulation. Co-P CWs were the most stable and had the best removal efficiency of COD (chemical oxygen demand) in urban sewage, with an average removal rate of 74.9% at 7 weeks, which was 14 and 7.3% higher than those of the QS-P CWs and Co CWs, respectively. The power generation performance of the Co-P CWs was also the best. During operation, the voltage remained the highest (377.9–222.0 MV). The microbial community diversity, richness, and utilization rate of the six categories of carbon sources of Co-P CWs were the highest, with the dominant genera being organic matter aerobic degrading bacteria, electrochemically active bacteria, and ammonia-oxidizing bacteria. The microbial richness in coke CWs exhibited high microbial activity in the entire bed, not only at the inlet. This indicates that the system transfers electrons to the conductive material by relying on the metabolism of microorganisms; electrons generated at the bottom of the bed are directly transmitted to the bed surface through the conductive material, resulting in a uniform distribution of electrons throughout the bed and high microbial activity. Therefore, the conductivity-enhanced CWs effectively alleviated the reduction in wetland purification capacity. [Display omitted] • Coke filler has the best organic removal and high electric output. • Microbial richness in coke CW does not depend on the carbon source concentration. • Coke CW exhibits high microbial activity in the whole bed. • The surface and bottom layer show different types of carbon source metabolism. • Plants can enhance the zonal enrichment of functional microorganisms in coke CW. [ABSTRACT FROM AUTHOR]

[Display omitted] • A cavity engineering strategy was introduced to be synthesize MOFs-derived MnO x. • The MnO x -100 catalyst exhibited best ethyl acetate degradation under light irradiation. • Hollow structure could improve the carrier separation and light absorption capacity. • More exposed Mn4+ sites provided abundant adsorption sites and narrower band gap. • The introduction of light would change the degradation pathways of ethyl acetate. The designed synthesis of hollow-structure catalysts is central for enhancing the absorption and utilization of light irradiation, which is the core process of improved photothermal catalytic activity of VOCs. Herein, we introduced a viable cavity engineering for the fabrication of hollow MnO x -m architectures with a well-defined central space by in situ polyvinylpyrrolidone (PVP)-assisted Mn-BTC self-aggregation. The optimized MnO x -100 catalyst with hollow cavity environment exhibited approximately 96% ethyl acetate degradation toward CO 2 , stability and moisture resistance under light irradiation, which was much better than the traditional Mn-based MOFs derivatives (MOF-74-O and MIL-100-O). Combined experiment and DFT calculations, the more exposed Mn4+ sites in the MnO x -100 catalyst through a hollow cavity engineering could provide abundant adsorption sites, lower temperature reducibility and narrower band gap, and its hollow structure endowed with significant advantages for the separation efficiency of photogenerated carriers and light absorption capacity. Moreover, coexistence of photocatalysis, thermocatalysis and photoactivation in this catalyst system synergistically participated in the light-driven photothermal catalytic ethyl acetate oxidation. Finally, in situ DRIFTS results revealed that the introduction of light could change the possible reaction pathway of ethyl acetate degradation over the MnO x -100 catalyst, and aldehyde and ethylene were generated as by-products or non-critical intermediates under light irradiation. The main degradation pathway of ethyl acetate degradation occurred through ethyl acetate → aldehyde, ethanol and acetic acid → methanol and formic acid → CO 2 and H 2 O. [ABSTRACT FROM AUTHOR]

• An environmental protection clean high-efficiency strong permeability and moistening material was developed. • Micro wetting dynamic characteristics of the new material were proved. • The dust reduction effect of the new dust suppression material is significantly better than that of the traditional surfactant. To further reduce the concentration of dust in coal mining, improve the working environment, ensure the occupational safety and health of miners, and improve the safety construction level of intelligent mines, in this study, alginate from Enteromorpha prolifera was extracted by plant extraction technology to prepare sodium alginate. Then, the extracted sodium alginate was modified by free radical polymerization graft copolymerization theory combined with micro-wetting mechanism to develop a strong permeability and moisturizing material suitable for specific coal types, and the characteristics of the material were tested and characterized. Through molecular dynamics simulation of the highly permeable and moistening material, the wetting mechanism of the material is clarified, and the diffusion coefficient of water molecules in gas coal is 1.37×10−4 cm2/s, It provides theoretical support for the technical system of mine dust prevention and control. Finally, the synthetic material is applied to the coal seam water injection process of the Qiwu coal mine so that the average dust reduction rate of total dust and exhalation dust before and after application is increased from approximately 50% when using the conventional surfactant to approximately 80% when using the strong permeability and moistening synthetic material. The effect is obviously better than that of the conventional surfactant, and the application effect is more remarkable. [ABSTRACT FROM AUTHOR]

• The most prevalent serotype of S. suis isolated from healthy pigs in this study belongs to serotype 29. • Multidrug resistance was observed in 98.7 % of S. suis isolates. • The multidrug resistance gene optrA was detected on the plasmid of S. suis for the first time. • The coexistence of pathogenicity island (PAI) and optrA in 3 S. suis isolates. Streptococcus suis is a pig pathogen and a vector of zoonotic diseases that can cause severe systemic infection in humans. S. suis can colonize the nasal cavity, tonsils, and upper respiratory, genital, and digestive tracts in healthy pigs. Here, to determine prevalence, serotype distribution, and antimicrobial susceptibility of S. suis in healthy pigs, we collected 1813 nasal cavity samples from healthy pigs raised on 17 independent farms in six Chinese provinces between 2016 and 2018. We obtained 223 S. suis isolates (12.3 %) and the antimicrobial susceptibility to a panel of 11 antimicrobial agents was measured by microbroth dilution. Most S. suis isolates (98.7 %) were resistant to at least three classes of antimicrobial agents. The optrA gene conferring resistance to oxazolidinones and phenicols was identified in the chromosome of 27 isolates and on a ∼40-kb plasmid in one isolate; to the best of our knowledge, this was the first report of plasmid-borne optrA gene in S. suis. The genetic environment of optrA showed substantial diversity and could be divided into eleven different types. Interestingly, some fragments of the 89 K pathogenicity island (PAI) were observed together with optrA in 3 isolates, which warrants further attention. Capsular serotypes of S. suis isolates were determined by multiplex PCR. Serotype 29 was the most prevalent, followed by serotype 7 and serotype 2. The presence of highly virulent serotype 2 strains may pose a threat to public health. [ABSTRACT FROM AUTHOR]