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To evaluate the longitudinal changes of retinal neurodegeneration and choroidal thickness in diabetic patients with and without diabetic retinopathy (DR).Prospective observational cohort study.This prospective observational cohort study recruited type 2 diabetic patients from a community registry in Guangzhou. All participants underwent annual ocular examinations via swept-source optical coherence tomography that obtained choroid thickness (CT), retinal thickness (RT), and ganglion cell-inner plexiform layer (GC-IPL) thickness. The changes in GC-IPL, CT, and RT between patients who developed incident DR (IDR) or remained non-DR (NDR) were compared during a 3-year follow-up.Among 924 patients, 159 (17.2%) patients developed IDR within the 3-year follow-up. A reduction in GC-IPL, RT, and CT was observed in NDR and IDR; however, CT thinning in patients with IDR was significantly accelerated, with an average CT reduction of -6.98 (95% CI: -8.26, -5.71) μm/y in patients with IDR and -3.98 (95% CI: -4.60, -3.36) μm/y in NDR patients (P.001). Reductions in average GC-IPL thickness over 3 years were -0.97 (95% CI: -1.24, -0.70) μm/y in patients with IDR and -0.76 (95% CI: -0.82, -0.70) μm/y in NDR patients (P = .025). After adjusting for confounding factors, the average CT and GC-IPL thinning were significantly faster in patients with IDR compared with those who remained NDR by 2.09 μm/y (95% CI: 1.01, 3.16; P = .004) and -0.29 μm/y (95% CI: -0.49, -0.09; P = .004), respectively. The RT in the IDR group increased, whereas the RT in the NDR group decreased over time, with the adjusted difference of 2.09 μm/y (95% CI: 1.01, 3.16; P.001) for central field RT.The rate of retinal neurodegeneration and CT thinning were significantly different between the eyes that developed IDR and remained NDR during the 3-year follow-up, but both groups observed thickness reduction. This indicates that GC-IPL and CTs may decrease before the clinical manifestations of DR.

The purpose of this study is to investigate whether the mitochondrial DNA (mtDNA) content can reflect the state of mosaic embryos.The study included 1669 blastocysts derived from 394 PGT-A cycles between January 2018 and December 2020, in which preimplantation genetic testing for aneuploidy was performed and mtDNA content was determined. The standard deviation (SD) of whole genomic sequencing data was calculated for quality control. mtDNA content was measured as the proportion of mtDNA to genomic DNA. 1558 blastocysts with SD values less than 4.0 and mtDNA values less than 0.4% were selected for statistical analysis.The mtDNA content of the PGT mosaic group was significantly higher than that of the PGT normal group (P 0.001). Twenty-six mosaic embryos were transferred, and the results were as follows: 2 out of 26 had undergone a spontaneous miscarriage, 15 were not pregnant, and 9 resulted in a live birth. There were significant differences in the mtDNA content between the miscarriage/non-pregnancy group and the live birth group (**P 0.01; ***P 0.001). There was no mosaic embryo with more than 0.157% mtDNA content found in the live birth group.This study demonstrates that mtDNA analysis has the ability to identify mosaic embryos with high developmental potential. It can be a valuable supplementary index for the selection of mosaic embryos for transfer. Larger studies with a greater sample size will further our understanding of the relationships between metabolic activity and mosaicism.

Metal-organic frameworks (MOFs) are an emerging class of porous materials with many unique properties that make them promising candidates for carbon dioxide (CO2) capture and storage. A better understanding of the behavior of CO2 adsorbed inside MOF will enable researchers to develop the ability of designing new MOF based materials with high CO2 adsorption capabilities. It is well known that presence of open metal sites (OMSs) can greatly enhance the gas adsorption capability of MOFs. MOF UTSA-74, a framework isomer of well-known MOF-74 has a unique feature that upon activation, a single metal ion has two OMSs. Therefore, it presents a unique opportunity to probe the dynamics of CO2 molecules adsorbed on these OMSs. In this work, the CO2 adsorptive properties of MOF UTSA-74 are examined with particular attention being paid to the dynamics of the CO2 adsorbed on these OMSs. Specifically, variable temperature 13C static solid-state nuclear magnetic resonance (SSNMR) experiments were conducted to directly monitor the behavior of 13CO2 in UTSA-74 at different loadings. All CO2 molecules undergo localized wobbling. At low loadings, some CO2 molecules jump among three OMSs from three different Zn atoms in the cross-section of the channel. Others hop back and forth between the two neighboring OMSs. At high loading, the three-site jump has ceased, but two-site hopping persists. The dynamical behavior of CO2 in UTSA-74 results from the unique Zn coordination environment. It was discovered that CO2 is less mobile in UTSA-74 than in its framework isomer, MOF-74-Zn.

Background Extraventricular neurocytoma (EVN) is a rare neurocytoma occurring in the brain parenchyma outside the ventricular system that shares similar biological behaviors and histopathologic characteristics with central neurocytoma. Reports of EVN localized in the brainstem and cerebellum are relatively uncommon. In addition, few cases with radiotherapy as the only treatment have been reported and their outcomes were unclear. Case Description We report a case of pathologically confirmed EVN of the brainstem and cerebellum in a 43-year-old male who presented with unprovoked nausea and dizziness. The patient received radiotherapy only and showed a favorable outcome during the 2-year follow-up period. Conclusions These results suggest that patients with EVN who are treated with radiotherapy without surgery may have a favorable prognosis.

One of the primary obstacles that has inhibited the development of solid-state batteries is the lower conductivity of solid electrolytes compared to liquid electrolytes. Li6PS5Br is a promising solid electrolyte for solid-state batteries due to its high ionic conductivity and low cost. Herein, we enhance the lithium conductivity by replacing S with Br and systematically tailor the composition and synthesis parameters to optimize the conductivity. Li5.5PS4.5Br1.5 exhibits higher ionic conductivity and better lithium compatibility than the bare Li6PS5Br. Although lithium metal is chemically unstable with Li5.5PS4.5Br1.5, stable cycling behavior in lithium symmetrical cells with small overpotential and resistance after 2500 ​h are achieved. Both the bare NCM622 and LiNbO3-coated NCM622 shows long cycling life with Li5.5PS4.5Br1.5 electrolyte in combination with In or lithium metal anodes. The LiNbO3 layer can effectively improve the capacity and cycling behavior of the solid-state battery using different anodes. Moreover, the electrochemical performances of Li5.5PS4.5Br1.5-based solid-state batteries are influenced by the charge/discharge voltage windows.

pH-sensitive polyethylene glycol-conjugated urokinase nanogels (PEG-UK) is a new form of urokinase (UK) nanogels that could release UK at certain pH values. In our former study, we demonstrated that the pH value in the infarcted brain significantly declined to the level that could trigger the delivery of UK from PEG-UK. Thrombolysis is recommended as the first choice for ischemic stroke within the time window. However, it is common for the patients to miss the thrombolysis time window, which is one of the major causes of bad prognosis from ischemic stroke. It remains promising for seeking therapeutic approaches for ischemic stroke by investigating potential protective reagents delivered out of the usually thrombolysis time window. In this study, the protective effect of administration of PEG-UK outside the usual time window and the underlying mechanisms were investigated. PEG-UK was administrated 2 h and a half after ischemic stroke Delayed administration of PEG-UK significantly ameliorated the severity of neurological deficits of permanent middle cerebral occlusion (pMCAO) rats and reduced the infiltration of inflammatory cells and the concentration of interleukin 1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the brain tissues. The content of water and the leakage of Evans Blue (EB) in the PEG-UK group were also decreased. Maintenance of the expression of platelet-derived growth factor-C (PDGF-C) and inhibition of the upregulation of metalloproteinase proteins, low-density lipoprotein receptor-related protein (LRP), nuclear factor κB (NF-κB) p65 and cyclooxygenase-2 (Cox-2) were observed through western blotting and realtime PCR in the PEG-UK group. Besides, delayed administration of PEG-UK attenuated the up regulation of Caspase8 and Caspase9 and the cleavage of Caspase3 and poly (ADP-ribose) polymerase 1 (PARP1) in ischemic lesion sites. Moreover, PEG-UK treatment also inhibited the upregulation and phosphorylation of N-methyl-D-aspartic acid receptors (NMDARs), which has been revealed to play a vital role in mediating excito-neurotoxicity in ischemic stroke. In conclusion, through the inhibition of LRP/NF-κB/Cox-2 pathway, the Caspase cascade and activation of NMDARs, administration of PEG-UK outside the usual time window could still exert protective effects in pMCAO rats through the maintenance of the integrity of BBB and the inhibition of apoptosis and excito-neurotoxicity.

Gray mold caused by Botrytis cinerea is the most important disease in postharvest tomato fruit. Inducing resistance to fungal pathogens in the harvested fruit and vegetable is a promising approach to control postharvest losses. In the present study, the effect of l-glutamate on induction of resistance to B. cinerea and the underlying mechanisms were investigated. The results indicated that l-glutamate at 100 ppm was effective in reducing the gray mold of tomatoes after inoculation of the pathogen. Gene expressions of nine glutamate receptors, four pathogenesis-related proteins and the content of amino acids were affected by l-glutamate treatment. Furthermore, the metabolites of l-glutamate, including GABA, Met, Lys and Arg, could also induce significant resistance against B. cinerea in tomato fruit. Our findings suggested that l-glutamate treatment may represent a promising method for managing postharvest decay of tomato fruit.

With over 2 million new cases annually, stroke is associated with the highest disability-adjusted life-years lost of any disease in China. The burden is expected to increase further as a result of population ageing, an ongoing high prevalence of risk factors (eg, hypertension), and inadequate management. Despite improved access to overall health services, the availability of specialist stroke care is variable across the country, and especially uneven in rural areas. In-hospital outcomes have improved because of a greater availability of reperfusion therapies and supportive care, but adherence to secondary prevention strategies and long-term care are inadequate. Thrombolysis and stroke units are accepted as standards of care across the world, including in China, but bleeding-risk concerns and organisational challenges hamper widespread adoption of this care in China. Despite little supporting evidence, Chinese herbal products and neuroprotective drugs are widely used, and the increased availability of neuroimaging techniques also results in overdiagnosis and overtreatment of so-called silent stroke. Future efforts should focus on providing more balanced availability of specialised stroke services across the country, enhancing evidence-based practice, and encouraging greater translational research to improve outcome of patients with stroke.

Semi-active systems have demonstrated excellent performance in vibration isolation, However, the tunable range of conventional variable stiffness elements is limited by the mount stiffness required to support a load. To improve the performance of low-frequency vibration isolation, a novel compact and contactless multi-layer electromagnetic spring (MES) with tunable negative stiffness is proposed in this paper. The negative stiffness is generated by the electromagnetic force between the coils and the magnets and can be tuned online by controlling the current. Based on a stiffness analysis model, a design procedure for configuring the MES is presented to expand the region where the stiffness is negative and to increase its tunable range. As a result, with only one type of magnet and coil, various negative stiffness elements with different stiffness characteristics can be manufactured, thereby reducing costs. To verify the dynamic behavior of the MES, a tunable high-static-low-dynamic stiffness (HSLDS) vibration isolator based on the MES was modeled and evaluated by applying it to a lidar. The experimental results demonstrate the following: the MES tuned the isolator online and broadened the isolation frequency band such that the isolator attenuated the vibration of the lidar, and it significantly improved the lidar modeling performance.

Objective We aimed to evaluate the value of 3D pseudocontinuous arterial spin-labeling (pCASL) perfusion imaging detected crossed cerebellar diaschisis (CCD) at different stages of intracerebral hemorrhage (ICH). Materials and methods We assessed bilateral cerebral blood flow (CBF) values of different brain regions and the relationships between the CCD and clinical status of 16 ICH patients. Results The ICH patients had significantly lower CBF values in the contralateral cerebellum in acute, subacute and chronic stages. The subacute CCD had a significant correlation with clinical status. Conclusions 3D pCASL may be an ideal tool to study the phenomenon and clinical consequences of ICH with CCD.

Summary Background No treatment has consistently shown efficacy in slowing disability progression in patients with secondary progressive multiple sclerosis (SPMS). We assessed the effect of siponimod, a selective sphingosine 1-phosphate (S1P) receptor 1,5 modulator, on disability progression in patients with SPMS. Methods This event-driven and exposure-driven, double-blind, phase 3 trial was done at 292 hospital clinics and specialised multiple sclerosis centres in 31 countries. Using interactive response technology to assign numbers linked to treatment arms, patients (age 18–60 years) with SPMS and an Expanded Disability Status Scale score of 3·0–6·5 were randomly assigned (2:1) to once daily oral siponimod 2 mg or placebo for up to 3 years or until the occurrence of a prespecified number of confirmed disability progression (CDP) events. The primary endpoint was time to 3-month CDP. Efficacy was assessed for the full analysis set (ie, all randomly assigned and treated patients); safety was assessed for the safety set. This trial is registered with ClinicalTrials.gov, number NCT01665144. Findings 1651 patients were randomly assigned between Feb 5, 2013, and June 2, 2015 (1105 to the siponimod group, and 546 to the placebo group). One patient did not sign the consent form, and five patients did not receive study drug, all of whom were in the siponimod group. 1645 patients were included in the analyses (1099 in the siponimod group and 546 in the placebo). At baseline, the mean time since first multiple sclerosis symptoms was 16·8 years (SD 8·3), and the mean time since conversion to SPMS was 3·8 years (SD 3·5); 1055 (64%) patients had not relapsed in the previous 2 years, and 918 (56%) of 1651 needed walking assistance. 903 (82%) patients receiving siponimod and 424 (78%) patients receiving placebo completed the study. 288 (26%) of 1096 patients receiving siponimod and 173 (32%) of 545 patients receiving placebo had 3-month CDP (hazard ratio 0·79, 95% CI 0·65–0·95; relative risk reduction 21%; p=0·013). Adverse events occurred in 975 (89%) of 1099 patients receiving siponimod versus 445 (82%) of 546 patients receiving placebo; serious adverse events were reported for 197 (18%) patients in the siponimod group versus 83 (15%) patients in the placebo group. Lymphopenia, increased liver transaminase concentration, bradycardia and bradyarrhythmia at treatment initiation, macular oedema, hypertension, varicella zoster reactivation, and convulsions occurred more frequently with siponimod than with placebo. Initial dose titration mitigated cardiac first-dose effects. Frequencies of infections, malignancies, and fatalities did not differ between groups. Interpretation Siponimod reduced the risk of disability progression with a safety profile similar to that of other S1P modulators and is likely to be a useful treatment for SPMS. Funding Novartis Pharma AG.

This paper describes the conformational analysis of 1,2-dichloroethane adsorbed into three different metal-organic frameworks, MIL-53(Al), MIL-68(In), MIL-53-NH2(Al), by using FT-Raman spectroscopy in combination with powder XRD and TGA. For non-polar frameworks, the main guest-host interactions are van der Waal interactions between the C H bonds of 1,2-dichloroethane (DCE) and the π system of terephthalate ligands. The polar framework of MIL-53-NH2 is able to stabilize the gauche conformation of DCE at room temperature. The conformational enthalpy of each system was determined through variable temperature FT-Raman spectroscopy. Furthermore, the line-width of the Raman bands provides information regarding the molecular motion of the halocarbons at various temperatures inside the framework.

Auxin is a vital plant growth regulator and can also take a part in plant defense. The study focused on the efficacy of the major active form of auxin, indole-3-acetic acid (IAA), on inhibition of blue mold rot caused by Penicillium expansum in pear fruit wounds and the possible action mechanisms involved. Results indicated that IAA at 100–500 μg mL−1 significantly enhanced the resistance of pear fruit against blue mold rot when the treating interval was between 24 and 48 h, while it had no direct antifungal activities towards P. expansum in vitro. Moreover, IAA induced a significant increase on the activities of β-1,3-glucanase (GLU), chitinase (CHI) and phenylalanine ammonia-lyase (PAL) in pear fruit. Furthermore, the data revealed that the expressions of endoglu9, CHI4, PR1, PR4 and PAL were up-regulated substantially in pear fruit treated with IAA. The all findings highlight the efficiency of IAA on inducing the natural resistance of pear fruit against P. expansum and suggest that the mechanisms may be closely related to the elicitation of defense-related enzymes and genes.

As the first and most famous cryptocurrency-based blockchain technology, Bitcoin has attracted tremendous attention from both academic and industrial communities in the past decade. A Bitcoin network is comprised of two interactive parties: individual miners and mining pool managers, each of which strives to maximize its own utility. In particular, individual miners choose which mining pool to join and decide on how much mining power to commit under limited constraints on the mining budget and mining power capacity; managers of mining pools determine how to allocate the mining reward and how to adjust the membership fee. In this work we investigate the miners’ and mining pool managers’ decisions in repeated Bitcoin mining competitions by building a Monte-Carlo discrete-event simulation model. Our simulation model (i) captures the behavior of these two parties and how their decisions affect each other, and (ii) characterizes the system-level dynamics of the blockchain in terms of the mining difficulty level and total mining power. In addition, we study the sensitivity of system performance metrics with respect to various control parameters. Our analysis may provide useful guidelines to mining activity participants in the Bitcoin network.

On the way to impel Rhodosporidium paludigenum to behave like a serviceable and beneficial biocontrol antagonist, it was found that adding different concentrations of N-acetylglucosamine (GlcNAc) during the culture can reduce the incidence of pears caused by Penicillium expansum. 0.1 % GlcNAc is an optimal concentration in the range of 0.001 %–2 %. R. paludigenum, cultivated and gathered from the medium with a final concentration of 0.1 % GlcNAc, declared the best impact on restraint on P. expansum on pears. This inhibitory effect is analogous to the consequence of spore germination experiments in vitro. The R. paludigenum gathered after GlcNAc induction, at the same time, displayed exceptional viability and vigour under different stress conditions, including sodium chloride (NaCl), calcofluor white (CFW), Congo red (CR) and sodium dodecyl sulfate (SDS). The enzyme activity and the relative gene expression levels of some antioxidant-related enzymes in R. paludigenum, including peroxisomal catalase (CAT), thioredoxin reductase (TrxR), glutathione peroxidase (GSH-PX), glutathione reductase (GR) and superoxide dismutase (SOD), were detected to be up-regulated in further testing. At the same time, the reactive oxygen species (ROS) remained at a low status.

A vibration isolator based on a tunable negative stiffness mechanism combines the advantages of high-static-low-dynamic stiffness (HSLDS) isolators to expand the isolation frequency band and variable stiffness isolators to suppress resonance. In this paper, a novel tunable negative stiffness spring using Maxwell normal stress (SMNS) is proposed. The stiffness tunable range and energy utilization efficiency are greatly improved due to the newly designed magnetic circuit. Moreover, the electromagnetic negative stiffness device has the advantages of no friction, no backlash, compact structure and easy control. An analytical model of the electromagnetic force is built based on magnetic circuit analysis, and the parameter analysis is performed. An HSLDS isolator is constructed by connecting the SMNS in parallel with a linear isolator. The stiffness and vibration isolation performance are measured. The experimental results show that the SMNS produces an online tunable negative stiffness, which expands the isolation bandwidth and significantly improves the vibration isolation performance.

The launch of China's new national urbanization plan, coupled with increasing concerns about air pollution, calls for better understandings of the nexus between urbanization and the air pollution–related health. Based on refined estimates of PM 2.5 related mortality in China, we developed an Urbanization–Excess Deaths Elasticity (U–EDE) indicator to measure the marginal PM 2.5 related mortality caused by urbanization. We then applied statistical models to estimate U–EDE and examined the modification effects of income on U–EDE. Urbanization in China between 2004 and 2012 led to increased PM 2.5 related mortality. A 1% increase in urbanization was associated with a 0.32%, 0.14%, and 0.50% increase in PM 2.5 related mortality of lung cancer, stroke, and ischemic heart disease. U–EDEs were modified by income with an inverted U curve, i.e., lower marginal impacts at the lowest and highest income levels. In addition, we projected the future U–EDE trend of China as a whole and found that China had experienced the peak of U–EDE and entered the second half of the inverted U–shaped curve. In the near future, national average U–EDE in China will decline along with the improvement of income level if no dramatic changes happen. However, the decreased U–EDE only implies that marginal PM 2.5 –related mortality brought by urbanization would decrease in China. Total health damage of urbanization will keep going up in the predictable future because the U–EDE is always positive.

Ga-MIL-53 is a metal-organic framework (MOF) that exhibits a “breathing effect,” in which the pore size and overall MOF topology can be influenced by temperature, pressure, and host-guest interactions. The phase control afforded by this flexible framework renders Ga-MIL-53 a promising material for guest storage and sensing applications. In this work, the structure and behavior of four Ga-MIL-53 phases ( as , ht , enp and lt ), along with CO 2 adsorbed within Ga-MIL-53 at various loading levels, has been investigated using 69/71 Ga solid-state NMR (SSNMR) experiments at 21.1 T and 9.4 T. 69/71 Ga SSNMR spectra are observed to be very sensitive to distortions in the octahedral GaO 6 secondary building units within Ga-MIL-53; by extension, Ga NMR parameters are indicative of the particular crystallographic phase of Ga-MIL-53. The evolution of Ga NMR parameters with CO 2 loading levels in Ga-MIL-53 reveals that the specific CO 2 loading level offers a profound degree of control over the MOF phase, and the data also suggests that a re-entrant phase transition is present. Adsorption of various organic compounds within Ga-MIL-53 has been investigated using a combination of thermal gravimetric analysis (TGA), powder X-ray diffraction (pXRD) and 69/71 Ga SSNMR experiments. Notably, pXRD experiments reveal that guest adsorption and host-guest interactions trigger unambiguous changes in the long-range structure of Ga-MIL-53, while 69/71 Ga SSNMR parameters yield valuable information regarding the effect of the organic adsorbates on the local GaO 6 environments. This approach shows promise for the ultra-wideline investigation of other quadrupolar metal nuclei in MIL-53 ( e.g. , In-MIL-53) and MOFs in general, particularly in regards to adsorption-related applications.

Isolation of lipophilic compounds by countercurrent chromatography (CCC) is a challenge because biphasic solvent systems in which these compounds distribute evenly are difficult to obtain. In this article we present novel applications of lipid compound isolation from natural sources. Conjugated linolenic acids (CLnAs, log KOW ∼7) were isolated from pomegranate oil using a solvent system consisting of n-heptane/methanol/water 100:91:9 (v/v/v). The CLnA fraction was free of other fatty acids but consisted of different isomers which were not resolved from each other. In the less polar range (log KOW ∼12), three tocotrienols (α-, γ- and δ-tocotrienol) were isolated from a vitamin E capsule produced from palm oil by using the solvent system n-hexane/acetonitrile/benzotrifluoride (BTF) at a ratio of 10:6.5:3.5 (v/v/v). Between 36 and 65 mg of each of the three tocotrienols were obtained in one injection with purities >97%. Advantages and disadvantages of the “BTF system” are discussed by comparing the phase composition with the simple n-hexane/acetonitrile system and by the fractionation of phytosterols (log KOW ∼9.5) from rapeseed oil.

Ceramide has been recognized as a second messenger that regulates several intracellular processes in neuronal cells. However, its role in neuronal autophagy is not fully understood. In this study, we used a human neuroblastoma cell line (SH-SY5Y) to investigate the mechanisms underlying C2-ceramide-mediated cell death and autophagy. C2-ceramide induced caspase-3-independent cell death. In addition, C2-ceramide induced autophagy, decreased the activation of Akt and mTOR, and increased the activation of JNK and ERK1/2. However, only inhibition of ERK1/2 with PD98059 prevented C2-ceramide-induced autophagy, indicating that the ERK1/2 pathway contributes to ceramide-induced autophagy. According to the results of the flow cytometric assays, C2-ceramide-induced cell death was increased by 3-methyadenine (3-MA) and decreased by rapamycin. Furthermore, the generation of reactive oxygen species (ROS) in the cells was increased by 3-MA and decreased by rapamycin. Based on these datas, autophagy protected SH-SY5Y cells from C2-ceramide-induced cell death by decreasing ROS production. Therapeutic strategies that regulate autophagy may be used in the treatment of neurological disorders associated with ceramide-induced cell death.

It is essential to extract dynamic information about a patient's heart from a medical X-ray angiography image sequence for a quantitative medical diagnosis. As the motions included in the angiography sequences are the mixture of various motion signals, such as the body's integral translation, respiratory motion, cardiac impulse, and tremor, automatic separation of these signals challenges the effectiveness of the image information processing method. This paper has proposed an optimal time-frequency domains iteration separation algorithm for multi-motion parameters (TFISA-MMP) to obtain the physiological parameters including the translation. The main procedures of the TFISA-MMP algorithm include three parts. First, the algorithm automatically extracted a set of relatively stable branch points from the coronary artery angiography image, and then automatically tracked these branch points in the sequence image to obtain their motion curves that changed with the time. Second, with the guidance of the multi-motion parameter model, the initial values of each component were estimated based on Discrete Fourier Transformation (DFT). Moreover, the initial values of each motion component were optimized using the global mean square minimum error between the estimated reconstructed signal and original signal and the local mean square minimum error in the frequency domain for each frequency component. Finally, these motion components were estimated by minimizing the residual signal between the original signal and the reconstructed signal via the loop iteration to obtain the estimated optimal motion components, such as two-dimensional (2D) heartbeat, tremor, respiratory motion, and translational motion. Both visible human coronary model simulation experiments and the clinical experiments of single-arm X-ray angiography images of many individuals verified the correctness, validity, and clinical applicability of the separation method.

China has experienced rapid urbanization in recent decades along with dramatic economic growth. Previous studies have shown that urbanization has both positive and negative effects on health. However, there is a lack of research on the overall effects of urbanization on the epidemic transition of environmental health risks considering various pathways in China. In the present study, we studied the contributions of different aspects of urbanization in China to epidemic transitions using provincial and multi-year (1995, 2000, 2005, and 2010) panel data. Statistical models with fixed and random effects were developed to explore the impacts of different urbanization indicators on the overall epidemic transition of environmental health (general model) and the changes in cause-specific mortality rates of typical diseases (cause-specific models). The results show that the impacts of non-communicable diseases continue to grow during the urbanization process in China. The ratio of communicable disease-related mortality to non-communicable disease-related mortality continues to decrease over time. The general model shows that the improved medical conditions (coefficient = −0.0011, P = 0.037), the improved urban infrastructure (e.g., tap water supply) (coefficient = −0.00065, P

While recent assessments have quantified the burden of air pollution at the national scale in China, air quality managers would benefit from assessments that disaggregate health impacts over regions and over time. We took advantage of a new 10 × 10 km satellite-based PM2.5 dataset to analyze spatial and temporal trends of air pollution health impacts in China, from 2004 to 2012. Results showed that national PM2.5 related deaths from stroke, ischemic heart disease and lung cancer increased from approximately 800,000 cases in 2004 to over 1.2 million cases in 2012. The health burden exhibited strong spatial variations, with high attributable deaths concentrated in regions including the Beijing–Tianjin Metropolitan Region, Yangtze River Delta, Pearl River Delta, Sichuan Basin, Shandong, Wuhan Metropolitan Region, Changsha–Zhuzhou–Xiangtan, Henan, and Anhui, which have heavy air pollution, high population density, or both. Increasing trends were found in most provinces, but with varied growth rates. While there was some evidence for improving air quality in recent years, this was offset somewhat by the countervailing influences of in–migration together with population growth. We recommend that priority areas for future national air pollution control policies be adjusted to better reflect the spatial hotspots of health burdens. Satellite-based exposure and health impact assessments can be a useful tool for tracking progress on both air quality and population health burden reductions. Keywords: Air pollution, PM2.5, Health burden, Temporal, Spatial, China

To translate scientific evidence into policy decisions, a universal, integrate and rapid–calculation model is needed for estimating the air quality associated health co–benefits of climate change mitigation strategies. This study developed such a greenhouse gas policy assessment model (GHG–PAM) based upon the annually published energy balances tables. To examine the applicability of this model, we select Suzhou, one of the national low-carbon pilot cities located in the east of China, as a case study. It was determined that carbon dioxide (CO2) emissions in Suzhou would increase from 148 million tons in 2010 to 297, 284, 180, and 173 million tons in 2020 under Business As Usual (BAU), Industrial Structure Dominated (ISD), Technology Dominated (TD), and Integrate Carbon Reduction (ICR) scenarios, of which only ICR scenario meets its carbon intensity target. Under the ICR scenario, the implementation of greenhouse gas policies reduces the air pollution associated burden of diseases, measured by Disability-Adjusted Life Years (DALY), by 44.1% in 2020 compared to BAU, although even with this scenario the burden of diseases would still be higher than that in 2010. In addition, the model can also identify sectors and industries with greater health co–benefits per unit CO2 emission reduction, which provides a useful guide for Suzhou's climate policy makers to formulate cost–effective measures. However, it should be carefully used where there is a mismatch between sectors with high potential for CO2 emission reductions and sectors with high health co–benefits per unit CO2 emission reduction.

The alteration of safety-secured yeast is a crucial step before scale applications. Based on previous studies, Pichia pastoris showed great potential and value to improve its biocontrol ability. The original sequences of antimicrobial peptide Ac-AMP2 and MiAMP1 were optimized according to the preference of Pichia pastoris and ligated into pPICZαA plasmid which is emerged as a high-performance vector for transformation and expression. The results of RT-qPCR and Western blotting could imply that pPICZαA/Ac-AMP2 and pPICZαA/MiAMP1 were successfully overexpressed in Pichia pastoris GS115. The peptide concentration of GS115/Ac-AMP2 reached a maximum value of 210 mg L−1 at 60 h while GS115/MiAMP1 was 220 mg L−1 at 96 h. The biocontrol experiment indicated that the recombinant strain GS115/Ac-AMP2 and GS115/MiAMP1 could highly suppress the pathogen Penicillium expansum in vivo, which was respectively 42 % (GS115/Ac-AMP2) and 29.2 % (GS115/MiAMP1) of incidence disease lower than the sterile distilled water treatment. In the case of the experimental results considered, the modified GS115/Ac-AMP2 and GS115/MiAMP1 might be promising biological agent in postharvest applications.

Lithium halide electrolytes with high ion conductivity and good cathode compatibility have shown great potential for solid-state batteries. Li3YBr6, with a conductivity of 0.39 mS/cm at room temperature, synthesized by mechanical milling (BM-Li3YBr6), which can be further increased by heat treatment. The annealing parameters are tailored to obtain pure Li3YBr6 (AN-Li3YBr6) with a higher conductivity of 3.31 mS/cm by annealing the BM-Li3YBr6 at 500 °C for 5 h. The higher conductivity of AN-Li3YBr6 compared to the previously-reported results is due to the lower activation energy. NMR and simulation results show that the lithium ion migration between Li-1 and Li-2 sites along the [001] direction is the major obstacle for lithium diffusion in AN-Li3YBr6. The K- and L3-edge X-ray absorption near-edge structure (XANES) of Y for BM-Li3YBr6 and AN-Li3YBr6 showed that Y exists with similar local structures. The increased vibrations of AN-Li3YBr6 due to increased temperatures increase the rate of lithium jumping from one site to another, yielding higher lithium ion mobility. Lithium nuclear density maps prove that the mobile lithium on the 4g(Li) site is more sensitive to the varying temperatures. Both BM- and AN-Li3YBr6 are incompatible with Li, however, an annealing process can improve the electrochemical stability. Both the experimental and simulation results confirm the anode incompatibility between In and AN-Li3YBr6. To mitigate the cathode and anode incompatibility with AN-Li3YBr6, a LiNbO3 coating layer and a Li5.7PS4.7Cl1.3 buffer layer are introduced at the cathode side and anode side, respectively, to assemble all-solid-state batteries with improved capacity and cyclability.

We described a female patient with anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis occurring sequentially with neuromyelitis optica spectrum disorders (NMOSD). The 19-year-old patient initially presented a diencephalic syndrome with aquaporin-4 immunoglobulin G antibodies (AQP4-IgG) and brain lesions which involving bilateral medial temporal lobes and periependymal surfaces of the third ventricle on magnetic resonance imaging (MRI). Ten months later, the patient developed cognitive impairment, psychiatric symptoms and dyskinesia with left basal ganglia lesions on brain MRI. Meanwhile, the anti-NMDAR antibodies were positive in the patient's serum and cerebrospinal fluid, while the screening tests for an ovarian teratoma and other tumors were all negative. Hence, the patient was diagnosed NMOSD and anti-NMDAR encephalitis followed by low-dose rituximab treatment with a good response. This case was another evidence for demyelinating syndromes overlapping anti-NMDAR encephalitis in Chinese patients.

Background Although chronic kidney disease has been linked to cerebral small-vessel disease (CSVD), a definite relationship between them has not been established. This study assessed whether low estimated glomerular filtration is associated with risk of different subtypes of CSVDs. Methods Electronic databases were systematically searched for studies reporting an odds ratio of the association between low estimated glomerular filtration and CSVD risk. Sixteen studies, including 10,534 participants, were identified. A fix effects model was applied and odds ratios (ORs) with 95% confidence intervals were presented. Results Overall, risk of CSVDs was greater in individuals with low estimated glomerular filtration (OR = 2.20). Stratified analyses consistently showed significant associations across different subtypes, with pooled OR being greatest in subjects with silent cerebral infarction (SCI) (OR = 2.71) and cerebral microbleed (OR = 2.70). A pooled estimate of studies showing OR as a continuous variable showed results consistent with the former analysis (OR = .98 per standard deviation decrease) in low estimated glomerular filtration. Conclusions This study revealed that low estimated glomerular filtration was significantly associated with risk of CSVDs. Low estimated glomerular filtration was most strongly associated with SCI (OR = 2.71) among subtypes of CSVDs.

pH-sensitive polyethylene glycol-conjugated urokinase nanogels (PEG-UKs) were previously reported to be a new form of UK nanogels that could release UK at certain pH values. In this study, we evaluated the effect of PEG-UK targeted to ischemic tissue with microcirculation failure in rat model of ischemic stroke and investigated the possible mechanisms of action.Surgeries were performed to induce persistent middle cerebral artery (MCA) occlusion in adult Sprague-Dawley rats. The pH distribution in the brain was mapped 1h after ischemia using a needle-type pH micro sensor. The release curve of active UK from PEG-UK was also mapped by a continuous measurement of the peripheral blood. The thrombolytic effects of PEG-UK, when it was administrated 1h after occlusion, including dynamic changes in the D-dimer level, neurological deficits and infarction volume, were observed. Next, the possible mechanisms underlying these effects were explored, including the BBB integrity and the extent of apoptosis and neurotoxicity. Additionally, the long-term effects of PEG-UK during the four weeks after treatment were evaluated using the dynamic changes in the body weights and clinical scores and the numbers of deaths and hemorrhagic transformations (HTs). To evaluate the systemic side effects of PEG-UK, the fluctuations of cytokines in the liver and kidney were evaluated.On average, MCA occlusion for 1h induced an approximately 0.49 decline in the pH value (from 7.12 to 6.73), and the lowest value was 6.32 in the predominantly affected region around the cortex. PEG suspended the release of UK from PEG-UK into the circulation. When it was administrated 1h after occlusion, PEG-UK treatment clearly reduced the severity of neurological deficits in the acute phase (P=0.001). The relative infarct volume also decreased significantly in PEG-UK rats (P0.001). As to the integrity of BBB, the EB leakage in the PEG-UK group was reduced (P=0.001). Maintenance of the expression of TIMP-1 (P=0.032) and claudin5 (P0.001) and inhibition of MMP9 upregulation (P0.001) were observed through both immunohistochemistry and Western blot in the PEG-UK group. Moreover, the expression of both NMDAR1 (P0.001) and Caspase9 (P=0.013) in PEG-UK-treated rats was reduced. As to the long-term prognosis, the rats in PEG-UK group recovered faster and better, and the numbers of deaths and HTs were not increased. No significant fluctuation in IL-1β and TNF-α was found in the PEG-UK-treated rats during the four post-treatment weeks. When PEG-UK was administrated 2.5h after occlusion, no clearly better outcomes were observed; however, the number of HTs was not increased.Treatment with PEG-UK decreased the severity of ischemic stroke by improving ischemic brain tissue and protecting the BBB and by inhibiting apoptosis and decreasing neurotoxicity. PEG-UK could further inhibit HT through its BBB protection effect. The administration of PEG-UK also improved the long-term prognosis and had no obvious systemic side effects in rats. Our data provide new insights into the thrombolytic treatment of ischemic stroke.

The lithium ion conductivity of lithium argyrodite can be improved by introducing Cl to tailor the S/Cl disorder in the structure. An ultrafast room temperature lithium ion conductivity of up to 6.4 mS/cm was achieved for Li5.7PS4.7Cl1.3. The synthesis parameters for Li7-xPS6-xClx (x = 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9) are systematically investigated to obtain pure lithium argyrodite phase with high ionic conductivity. AC impedance spectroscopy and 7Li spin-lattice relaxation NMR are utilized to show the enhancement of lithium ion conductivity caused by the incorporation of Cl. Ab initio molecular dynamics (AIMD) simulations proved that the introduction of Cl can effectively decrease the energy barriers for lithium ion migration in both short and long diffusion length scales. All-solid-state lithium batteries using LiNbO3-coated LiNi0.8Mn0.1Co0.1O2 cathode and Li5.7PS4.7Cl1.3 solid electrolyte display high discharge capacities and excellent cycling performances at relatively high current densities. EIS and galvanostatic intermittent titration technique (GITT) further confirm that the improved electrochemical performance can be attributed to the mitigation of voltage polarization and reduction of the interfacial resistance between the cathode and solid electrolyte.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited small artery disease caused by NOTCH3 gene mutation. Here we report clinical, pathological and genetic profiles of 29 newly-diagnosed CADASIL patients, evaluation of the CADASIL scale in Chinese CADASIL patients, and reanalysis of all reported mainland Chinese patients with identified NOTCH3 gene mutation. We found two novel mutations (p.C134G and p.C291Y) and 13 reported NOTCH3 mutations in the newly-diagnosed group. CADASIL scale score was less than the cutoff score in 19 of 53 Chinese patients with NOTCH3 mutation, generating only a sensitivity of 64.1%. At the time of study, the total number of genetically confirmed CADASIL cases reached 158 from 97 unrelated mainland Chinese families, with 9/97 (9.3%) sporadic patients. The NOTCH3 gene mutation profile showed 43 mutations, with hotspots in exon 4, followed by exon 3. The considerable variability in onset age and CADASIL scale score in patients carrying the same NOTCH3 missense mutation suggested no obvious phenotype–genotype correlation. In conclusion, we report two novel mutations which expand the NOTCH3 mutational spectrum. Exons 4 and 3 are hotspots in mainland Chinese patients with NOTCH3 mutation. The low sensitivity of CADASIL scale in our patients group indicated that the CADASIL scale should be refined according to the clinical characteristics of Chinese CADASIL patients when used in Chinese populations.

We study the effects of loading and nature of the zeolitic framework in the trans ⇌ gauche equilibrium of 1,1,2-trichloroethane (TCE) in zeolites with Faujasite (FAU) structure including sodium Y (Na-Y) and siliceous Y (Si-Y). TCE is used as a prototype molecule for the study of zeolite–chlorinated hydrocarbon interactions that determine conformational equilibrium. Conformational changes of TCE were sampled using empirical force fields and quantum mechanics/molecular mechanics (QM/MM) molecular dynamics (MD) in combination with replica exchange molecular dynamics (REMD). The population ratio of the conformers at high loading was compared with that found by Fourier transform (FT)-Raman spectroscopy and the results are in very good agreement. Comparison between the infinitely dilute limit of loading, and higher loading shows that the population ratio of the conformers at equilibrium depends strongly on the Si/Al ratio and consequently, the presence of charge compensating cations as well as the loading. At very low loading, in both Na-Y and Si-Y the population of the trans conformer is the largest with the exception of the empirical modeling that predicts the gauche conformer to be dominant in Na-Y. At the higher loading, in Na-Y the population the gauche conformer constitutes the great majority. In Si-Y the population of the trans conformer continues to dominate but the percentage of the gauche conformer increases substantially relative to the loading at the infinitely dilute limit. Such different conformational behaviors provide insight into the factors responsible for diffusion mechanisms and adsorption energies in the FAU-type zeolitic frameworks.

Molecular sieves have been scientifically and industrially important materials since their discovery. These porous, crystalline networks of tetrahedrally coordinated atoms bridged by oxygen are known as excellent catalysts. The framework of the aluminophosphate family of molecular sieves is itself non-catalytic, but through heteroatomic substitution these materials can diversify into, for example, the silicoaluminophosphate (SAPO) family of heterogeneous acid catalysts. Research into the methods by which these substitutions occur, as discoveries can lead to refined control over material property and function. SAPO-5 was chosen as model system of study. 27 Al, 29 Si and 31 P solid state NMR and PXRD were used as the primary methods of investigation. The SAPO-5 study determined that the dry gel conversion (DGC) methods of steam assisted conversion (SAC) and vapor phase transport (VPT) follow similar reaction pathways. After an initial difference caused by the lack of organic structure directing agent in the gel for the VPT method, crystallization is similar between methods, and silicon incorporation results in two populations of silicon sites. One represents isolated Si(OAl) 4 species well incorporated into the framework, while the other represents silica islands within the framework. The initial core of the nuclei is AlPO 4 in nature and the Si is gradually incorporated into the lattice as the crystals grow. The vapor phase silicon uptake (VPSU) method provides a contrast to this data, inducing nucleation that occurs concurrently with Si incorporation and producing only isolated Si(OAl) 4 species.

The crystallization of microporous material SAPO-37 was studied under hydrothermal synthesis (HTS) and dry gel conversion (DGC) conditions. The evolution of the intermediate phases as a function of crystallization time was followed by several techniques including PXRD, SEM, AFM, and solid-state NMR. For DGC, SAPO-37 crystallizes from a semi-crystalline layered precursor containing large pores and sodalite cages, whose structure is held by weak nonbonding interactions. Si atoms are only incorporated in the later stage of the crystallization via the formation of aluminosilicate species. Under HTS conditions, the crystallization pathway of SAPO-37 is somewhat similar to that for DGC. The AFM data suggest that the crystal growth mechanism is “birth and spread”, and the final SAPO-37 crystals have rough (1 1 1) surfaces terminated by different structural building units. The findings of the present work provide new physical insights into the formation of SAPO-37.

The pressure-induced anomalously high AC conductivity of zeolite NaA mixed with water was measured by impedance spectroscopy at various water/zeolite ratios. The conductivity reaches a maximum value at 0.9–1.4 GPa with increasing water content of up to 20 wt.% in NaA + water. The high ionic conductivity of NaA compressed in water is interpreted to result from cation diffusion in the quasi-liquid Na+–H2O intra-channel system enhanced by the filling of additional H2O sites. The pressure range of anomalously high AC conductivity in NaA enlarges towards higher pressures with decrease of the water/zeolite ratio. An abrupt drop in conductivity observed at P > 1.5 GPa appears to be associated with freezing of intra-channel water. After pressure release, the overhydrated state of the zeolite kept in a closed container can be preserved for a long time, providing abnormally high conductivity which is comparable with that of Na+ β-alumina.

A novel Cu (II) magnetic ion-imprinted polymer (MIIP) was synthesized by surface imprinting technique combined with a sol-gel process. The adsorbent of Cu (II)-MIIP shows higher capacity and selectivity than that of magnetic non-imprinted polymers (MNIP). Adsorption capacities of Cu (II)-MIIP and MNIP are 24.2 and 5.2mg/g for Cu (II) ions, respectively. The selectivity coefficients of the Cu (II)-MIIP for Cu (II)/Zn (II) and Cu (II)/Ni (II) are 91.84 and 133.92, respectively. Kinetics studies show that the adsorption process obeys pseudo-second-order rate mechanism with an initial adsorption rate of 132.48 for Cu (II)-MIIP and 2.41mgg(-1)min(-1) for MNIP. In addition, no obvious decrease was observed after up to five adsorption cycles, indicating that the Cu (II)-MIIP is of high stability.

The formation of microporous molecular sieve AlPO4-18 under the dry gel conversion (DGC) conditions was examined. The evolution of the dry gel was monitored by powder XRD, SEM and, in particular, solid-state NMR techniques. The results show that the aluminophosphate (AlPO) amorphous dry gel is first converted to a layered AlPO phase. The layered intermediate has some resemblances to AlPO4-18 and is held together by very weak non-bonding interactions. Continuous heating results in the transformation of this layered phase into AlPO4-18 via reorganizations and condensations of P and Al sites. Three non-equivalent P sites of AlPO4-18 develop at different rates during the evolution.

Novel magnetic and hydrophilic molecularly imprinted polymers (mag-MIPs) were prepared by an inverse emulsion-suspension polymerization to remove water-soluble acid dyes from contaminated water with 1-(α-methyl acrylate)-3-methylimidazolium bromide (1-MA-3MI-Br) being utilized as a new functional monomer. The thermal stability, chemical structure and magnetic property of the 1-MA-3MI-Br-mag-MIPs were characterized by the thermal-gravimetric analyzer (TGA), Fourier transform infrared spectrometer (FT-IR) and vibrating sample magnetometer (VSM), respectively. Moreover, effect of concentration and pH value of water-soluble acid dye solutions was optimized. Compared with the methyl acrylic acid and 4-vinylpyridine modified mag-MIPs, the 1-MA-3MI-Br-mag-MIPs showed enhanced removal efficiency. Kinetic studies depicted that the adsorption process on 1-MA-3MI-Br-mag-MIPs followed pseudo-second-order rate mechanism. Investigation results of 5 times removal-regeneration cycles by employing the 1-MA-3MI-Br-mag-MIPs showed that the resulting material was with high stability.

A 43-year-old man was admitted for right upper and lower limb weakness and aphasia. He had suffered dizziness and transient blindness 6 months ago and had also been found lying in the bathroom on another occasion. Multiple cerebral infarctions were confirmed by brain CT scan and MRI. Diffuse nodes in the mediastinum and postperitoneum had been found in pulmonary CT scans and MRI scans since 1999. Pulmonary CT scan revealed multiple bilateral pneumatoceles in the lungs. Contrast CT scan showed an enlarged azygos vein on the right side of the spinal column and an enlarged azygos arch. CT scan-guided biopsy revealed a few fibers, fat, and vascular tissues in the mass. Transcranial Doppler bubble test showed gas microembolic signals in both middle cerebral arteries. Pulmonary digital subtraction angiogram confirmed an enlarged azygos vein. A fistula was found between the pulmonary and azygos veins with turbulent flow from pulmonary to azygos at rest. Cavography revealed that the pulmonary vein appeared simultaneously with the superior cava vein during Valsalva maneuver. In summary, the pathway of cerebral embolism was based on three pathologic mechanisms: (1) increased inferior vena cava pressure, (2) enlarged right azygos aneurysm, and (3) the presence of a fistula between the azygos and pulmonary veins.

The infrared and Raman spectra of crystalline tetra-n-propylammonium bromide, (n-C 3 H 7 ) 4 NBr, have been measured in the 3000 – 700 cm −1 region and vibrational assignments are proposed in part on the basis of the known crystal structure. Pressure-tuning infrared and Raman studies of this material were also undertaken using a diamond-anvil cell. There is a pressure-induced phase transition occurring between 1.8 and 2.1 GPa, which is most likely a second-order transition. Some differences are noted between the infrared data reported here and those given in an earlier high-pressure infrared study. The spectroscopic results will be useful in examining zeolites involving (n-C 3 H 7 ) 4 NBr as a template.

Several Si and Co substituted AlPO4-based molecular sieves with AFI, AEL and CHA structures including SAPO-n and CoAPO-n (where n = 5, 11 and 34) have been synthesized under dry gel conversion (DGC) conditions by using the pre-prepared AlPO-based precursors which have been demonstrated previously to be structurally related to the target molecular sieves. We show that highly crystalline SAPO-n and CoAPO-n can be prepared by this approach. Unlike conventional DGC method where the Si source is mixed with P and Al sources at the very beginning to form an initial amorphous dry gel, in this work the Si is slowly introduced to the surface of the dry powder of the semi-crystalline or crystalline AlPO-based precursor via vapor phase, and subsequently incorporated into the framework gradually. The Si environments in the SAPOs prepared by this approach appear to be more diversified compared to those in the corresponding sieves made by the normal hydrothermal synthesis (HTS) method. One feature of this synthesis is that the Si substitution in the lattice may only occur at some specific positions. This is due to the fact that since certain P sites in the precursors are directly carried into the framework of the final sieves, they are not available for Si incorporation. This finding may have implication to the locations of the catalytic sites in the SAPO-based catalysts. Similarly, for CoAPO-n, the Co source was mixed with the preformed AlPO-based precursor before DGC treatment. CoAPO-5 has a higher degree of the Co incorporation than that of the CoAPO-5 made under normal HTS conditions.

This work examined the formation of a catalytically important microporous material, SAPO-34, in the presence of HF under hydrothermal synthesis conditions. The local environments of P, Al, F and Si atoms in several solid phases obtained at different stages of crystallization were characterized by several solid-state NMR techniques including (31)P, (27)Al, (19)F and (29)Si MAS, (27)Al triple-quantum MAS, (31)P{(27)Al} transfer of populations in double-resonance, (27)Al{(31)P} rotational-echo double-resonance (REDOR), (27)Al--(31)P heteronuclear correlation spectroscopy, (31)P{(19)F} and (27)Al{(19)F} REDOR as well as (1)H--(31)P cross polarization. The NMR results provide the new insights into the formation of SAPO-34.

The adsorption of toluene inside zeolite Na–Y was investigated by solid-state NMR spectroscopy. The environment of Na + ions at different sites in Na–Y before and after adsorption was characterized by 23 Na magic-angle spinning (MAS) NMR. The information on the dynamic behavior of guest molecules inside the supercage of Na–Y was obtained by analyzing wideline 2 H NMR spectra. The effect of loading level and temperature on molecular dynamics was also examined. The cation–sorbate interactions were directly probed by 23 Na{ 1 H} rotational-echo double-resonance (REDOR) experiments at different temperatures. Molecular Monte Carlo simulations were also performed to assist in the interpretation of the NMR data. 23 Na MAS and 23 Na{ 1 H} REDOR results show that each toluene molecule is facially coordinated to a Na + ion at the SII site in the supercage, forming a π-complex. The adsorption also causes the Na + ions initially located at the SI′ site to slightly shift to a new position within the sodalite cage, but has little effect on the Na + at the SI site. The 2 H NMR results indicate that the toluene molecules undergo a 2-site flip around the molecular long axis in addition to the methyl group rotation about its C 3 axis. 23 Na MAS spectra suggest that the adsorptive behavior of benzene and p -xylene in Na–Y is similar to that of toluene/Na–Y. 23 Na{ 1 H} REDOR results further indicate that inside the supercage, the degree of molecular motion follows the order of benzene > toluene > p -xylene.

Solid-state NMR was used to examine the local environments around the metal centers in microporous zirconium silicates and an aluminophosphate incorporated with Mg. 91 Zr and 25 Mg Quadrupolar Carr-Purcell Meiboom-Gill (QCPMG) spectra were obtained at different magnetic fields from which the quadrupolar and chemical shift parameters were extracted. The relationships between the NMR parameters and metal local structures were discussed. Theoretical calculations were performed on the model clusters. The work shows that using sensitivity enhancement techniques such as QCPMG and performing NMR experiments at the highest possible magnetic fields allow one to probe low-gamma, quadrupolar metal centres in microporous materials.