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In the application of GNSS in the velocity determination, it is often the case that some GNSS receivers give an opposite sign for the raw Doppler observations which do not correspond to the real Doppler shift. This is caused by different methods of the GNSS signal processing in different GNSS receivers. If the velocities of kinematic platforms are calculated by using raw Doppler observations from the GNSS receiver directly, the directions of the estimated velocities may be reversed, and the value of the velocity is wrong with respect to the actual movement. This would lead to incorrect results, and unacceptable for research and applications. To overcome this problem, a new method of sign correction for raw Doppler observations is proposed in this study. This algorithm constructs a correction function based on the GNSS carrier-phase-derived Doppler observations. To test this approach, GNSS data of GEOHALO airborne gravimetric missions have been used. The results show that the proposed method, which is straightforward and practical, can produce the correct velocity for a kinematic platform in any case, independent of the internal hardware structure and the specific way of the signal processing of the GNSS receivers in question.

Background: There is a paucity of mechanistic information on the DNA methylation and particulate matter (PM) exposure. This study aimed to investigate the association of PM and its component with DNA methylation, and the roles of DNA methyltransferase (DNMTs). Methods: There were 240 high-exposed, 318 low-exposed and 210 non-exposed participants in this study. Individual concentrations of PM, polycyclic aromatic hydrocarbons (PAHs) and metals were identified by the monitoring data in their workplaces. Urinary 1-OHP and metals were determined as exposure markers. The global DNA methylation (% 5mC) and the mRNA expression of DNMT1, DNMT3A and DNMT3B were measured. We used mediation analysis to evaluate the role of DNMTs expression on DNA methylation alteration induced by PAHs and metals components. Results: The decreasing trend of % 5mC was associated with increment of PM exposure in all subjects. We found that one IQR increase in total PAHs (3.82 μg/m3) and urinary 1-OHP (1.06 μmol/mol creatinine) were associated with a separate 6.08% and 7.26% decrease in % 5mC (P = 0.009, P

The symmetry of conjugate rifted margins is a first-order observable feature reflecting the geodynamic processes acting during and after continental rifting. The symmetry of the South China Sea (SCS) rifted margins can be deduced from comprehensive geophysical datasets on a continental-margin scale. Here, we combine three key approaches: (1) lateral fault distributions are delineated according to free-air gravity anomalies, (2) crustal stretching styles are mapped based on gravity inversion constrained by deep seismic profiles, and (3) total extension of conjugate margins is estimated according to margin restorations and tectonic settings. We infer a predominantly symmetric rifting style caused by pure shear extension, with only narrow domains of asymmetric deformation in continent-ocean transition (COT) regions that have undergone simple shear and where the lower crust of the highly thinned distal margin is embrittled before continental breakup. However, our analysis also suggests that this symmetry has been modified by post-rift geodynamic processes. Southward lower crustal flow, which occurred only on the southern margin due to the low viscosity of the lower crust and the slab pull induced by the subducting Proto-SCS plate during seafloor spreading, shifted the crustal stretching styles from symmetric to asymmetric. The collision between the southern margin and Borneo thickened the lower crust more than the upper crust at the southern end of the southern margin and shortened the southern margin. This event had a large impact on the SE margin but a small impact on the SW margin. We conclude that (1) for the SE and NE margins, the crustal stretching styles shifted from asymmetric to approximately symmetric, and the total extension shifted from symmetric to asymmetric; (2) for the SW and NW margins, the crustal stretching and total extension remained asymmetric and symmetric, respectively.

Due to the aggregation-caused quenching effect and near-infrared I poor penetration capabilities of common fluorescent molecules, their applications in visualized imaging and photoactivated treatment are limited. Therefore, new near-infrared II (NIR-II) molecule (named TST), which had the abilities of aggregation-induced emission (AIE) and photothermal therapy are synthesized. Moreover, in order to further improve its fluorescent yield and therapeutic effect, camptothecin prodrug (CPT-S-PEG) and novel immune checkpoint inhibitor AZD4635 are used to co-assemble with TST into nanoparticles for drug delivery. On account of the strong interaction of camptothecin and TST, the intramolecular rotation of TST is limited, thereby inhibiting non-radiation attenuation and promoting fluorescence generation when the nanoparticles are intact. As nanoparticles uptake by cancer cells, redox sensitive CPT-S-PEG is degraded and the nanoparticles disintegrate. The released TST enhances non-radiative attenuation and expedites photothermal conversion because of the removal of the constraint of camptothecin. Furthermore, photothermal therapy induces immunogenic cell death of cancer cells and releases abundant ATP into the tumor microenvironment to recruit immune cells. However, superfluous ATP is converted into immunosuppressive adenosine through the CD39-CD73-A2AR pathway. The AZD4635 released by photothermal disintegration of the nanoparticles just blocks this pathway timely, achieving favorable synergistic effect of photothermal therapy, chemotherapy, and immunotherapy.

In this research, the GNSS observation noise is assessed in details based on zero baseline data. The 24-h observations are collected from two CORS stations of Curtin University (32.0°S, 115.9°E) on February 8, 2017. The code and carrier phase observation noise is assessed in details for every system of GPS, GLONASS, BeiDou, Galileo, SBAS and QZSS and for every measurement type and every satellite. In addition, the observation noise by two different kinds of receiver is also assessed and compared. From the numerical results, we find that: (1) Among the six GNSS systems, the code noise of Galileo is the smallest, the noise of all observed Galileo code types are no more than 0.1 m and the noise of C8X is only around 1 cm; the GLONASS code noise is the biggest, the noise of code types C1C and C2C are around 0.25 m; (2) The noise can vary greatly for different code measurement types and there is at least one code measurement type in each system with noise smaller than 0.1 m; (3) For carrier phase, Galileo noise is slightly smaller than the other systems, the noise of all carrier phase types are smaller than 1 mm; GLONASS noise is the biggest, the noise of L2C and L2P are all bigger than 1 mm, some can reach about 1.7 mm; (4) Generally, there is no obvious noise difference for different carrier phase measurement types of each system, except for GLONASS, of which the noise of frequency band L2 is obviously bigger than that of L1; (5) For BeiDou, MEO and IGSO have similar carrier phase noise level, but the noise of GEO is clearly related to elevation angle, with the decrease of elevation angle, the noise will increase; (6) The carrier phase noise of different kinds of receiver may vary greatly, in this research, the numerical results show that the noise of JAVAD receiver are generally much smaller than TRIMBLE.

Jianping Xiong,1,* Xin Lu,1,* Weiyu Xu,1,* Yi Bai,1 Hanchun Huang,1 Jin Bian,1 Lei Zhang,1 Junyu Long,1 Yiyao Xu,2 Zhenjie Wang,2 Haitao Zhao1 1Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College (CAMS & PUMC), Beijing, China; 2Health Screening Center, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College (CAMS & PUMC), Beijing, China *These authors contributed equally to this work Background: Metabolic syndrome is regarded as a risk factor for hepatocellular carcinoma. However, no research has been conducted to investigate the association between metabolic syndrome and cholangiocarcinoma (CCA), especially in the Chinese population. Herein, a hospital-based case–control study was carried out in China to explore the association between metabolic syndrome and CCA risk. Patients and methods: In this study, 303 CCA patients (136 intrahepatic cholangiocarcinoma [ICC] and 167 extrahepatic cholangiocarcinoma [ECC]) were included, who were observed at Peking Union Medical College Hospital (PUMCH), from 2002 to 2014. Healthy controls were randomly selected from the database of PUMPH Health Screening Center. We retrospectively extracted metabolic syndrome and other possible risk factors from clinical records, followed by investigation of the relationship with CCA via calculation of ORs and 95% CIs using logistic regression analysis. Results: Metabolic syndrome was significantly and positively correlated with all CCA subtypes, with adjusted ORs (AORs) of 0.35 (95% CI =0.29–0.42) and 0.29 (95% CI =0.19–0.44) for ICC and ECC, respectively (both P

The variation in island arc magma production rates and their influencing mechanisms are of great significance since island arc magma is considered a main source of continental crust growth. The island arc magma directly originates from the molten mantle wedge, and the mantle melting is driven by fluids or melts from the subducted slab. Slab dehydration flux mainly depends on the slab thermal structures, and subducted slab melting requires a sufficiently high temperature. For the Aleutian subduction system, the subducted Pacific Plate has diverse thermal structures due to the existing fracture zones, ridges and slab window, so it is an ideal region for arc magma production rate research. However, the previous estimations are based on seismic profiles that only provide magma production rates at specific regions of the Aleutian arc, and these results are controversial. Here, we design a magma production rate estimation method based on gravity inversion constrained by deep seismic profiles. The first overview map of magma production rates along the Aleutian arc strike demonstrates that the magma production rates have the same trend as the slab dips, and the peaks correspond to the subduction of the fracture zones and ridges. The potential mechanisms for these correlations are as follows: (1) Slab water flux at subarc depths increases with increasing slab dip. More fluid flux would induce more mantle melting, and so the arc magma production rates are increased. (2) Water-rich serpentine is formed by hydrothermal alteration on or near the surface of the subducted slab when there are fracture zones. Serpentine decomposition at a depth of 80–120 km releases fluids in addition to the fluids released during normal slab dehydration. Therefore, more fluids induce more mantle melting and correspond a larger magma production rate. (3) The slab located in the Emperor Seamounts has a relatively high temperature and is also weak, so its melting is easier. Similarly, more slab melt means more mantle melt and a higher island arc magma production rate.

Autonomous underwater vehicle (AUV) acoustic navigation is challenged by unknown system noise and gross errors in the acoustic observations caused by the complex marine environment. Since the classical unscented Kalman filter (UKF) algorithm cannot control the dynamic model biases and resist the influence of gross errors, an adaptive robust UKF based on the Sage-Husa filter and the robust estimation technique is proposed for AUV acoustic navigation. The proposed algorithm compensates the system noise by adopting the Sage-Husa noise estimation technique in an online manner under the condition that the system noise matrices are kept as positive or semi positive. In order to control the influence of gross errors in the acoustic observations, the equivalent gain matrix is constructed to improve the robustness of the adaptive UKF for AUV acoustic navigation based on Huber&rsquo, s equivalent weight function. The effectiveness of the algorithm is verified by the simulated long baseline positioning experiment of the AUV, as well as the real marine experimental data of the ultrashort baseline positioning of an underwater towed body. The results demonstrate that the adaptive UKF can estimate the system noise through the time-varying noise estimator and avoid the problem of negative definite of the system noise variance matrix. The proposed adaptive robust UKF based on the Sage-Husa filter can further reduce the influence of gross errors while adjusting the system noise, and significantly improve the accuracy and stability of AUV acoustic navigation.

Cognitively inspired swarm intelligence algorithms (SIAs) have attracted much attention in the research area of clustering since it can give machine the ability of self-learning to achieve better classification results. Recently, the SIA-based multi-objective optimization (MOO) methods have shown their superiorities in data clustering. However, their performances are limited when applying to the clustering of remote sensing imagery (RSI). To construct an excellent MOO-based clustering method, this paper presents a social recognition-based multi-objective gravitational search algorithm (SMGSA) to achieve simultaneous optimization of two conflicting cluster validity indices, i.e., the Xie-Beni (XB) index and the Jm index. In the SMGSA, searching particles not only are guided by those elite particles stored in an external archive by the gravitational force but also learn from the social recognition of the whole population through the position difference. SMGSA thereby formed with outstanding exploitation ability. Comparison experiments on two public RSI data sets, including a moderate aerial image and a hyperspectral, validated that the MOO-based clustering methods could obtain more accurate results than the single validity index-based method. Moreover, the SMGSA-based method can achieve superior results than that of the multi-objective gravitational search algorithm without social recognition ability. The proposed SMGSA performs favorable balance between the two conflicting cluster validity indices and achieves preferable classification for the RSI. In addition, this study indicates that the swarm intelligence-based cognitive computing is potential for the intelligent interpretation and understanding of complicated remote sensing scene.

Traditionally, if full ambiguity resolution is not successful, partial ambiguity resolution (PAR) will be tried. However, identifying which subset of ambiguities to fix is not easy and is still an ...

PurposeUnder the guidance of Professor Wang Zhuquan’s channel-based working capital management concept, this paper, using a sample of A-listed companies from 2007 to 2013, aims to explore the possibility of measuring vendor relationships from the supply chain (channel) perspective for the first time, making universal testing for working capital management based on vendor relationships. Through systematically answering the question of who is the biggest beneficiary of working capital management based on vendor relationships and to discuss whether suppliers are more willing to provide “timely help” to weak enterprises or to exert an “icing on the cake” effect on strong enterprises, this paper provides a systematic explanation of the causes and economic consequences of working capital management based on vendor relationships.Design/methodology/approachThe authors constructed three models to test the hypotheses of this study. Model (1) explores the cause of working capital management based on vendor relationship from three angles: market position, industry competition degree and property right. Models (2) and (3) examine the economic consequences of working capital management based on vendor relationship from the two aspects of alleviating financing constraints and improving enterprises’ sustained growth capability.FindingsWorking capital management based on vendor relationships has a more significant “timely help” effect on weak companies, which was proved by the inclination of companies with lower market positions, higher industrial competition and private ownerships to adopt working capital management based on vendor relationships. From the perspective of economic consequences, while China’s listed companies benefit generally from working capital management based on vendor relationships, the weak enterprises are the biggest beneficiaries. Based on vendor relationships, the weak enterprises can relieve financing constraints and improve continuous growth capacity. It provides further evidence that suppliers could provide “timely help” to weak enterprises.Originality/valueThe results of this study find that the competition between supply chains replaces the competition among enterprises, and suppliers are more willing to provide “timely help” to weak enterprises rather than to exert an “icing on the cake” effect on strong enterprises. In addition, the working capital management based on vendor relationships facilitates the cooperation of enterprises and suppliers and improves the overall efficiency of the supply chain.

Parenteral therapy for severe and complicated malaria is necessary, but currently available parenteral antimalarials have their own drawbacks. As for recommended artemisinin-based combination therapy, antimalarial artemether and lumefantrine are limited in parenteral delivery due to their poor water solubility. Herein, the aim of this study was to develop the lipid-based emulsions for intravenous co-delivery of artemether and lumefantrine. The lipid emulsion was prepared by high-speed shear and high-pressure homogenization, and the formulations were optimized mainly by monitoring particle size distribution under autoclaved conditions. The final optimal formulation was with uniform particle size distribution (~ 220 nm), high encapsulation efficiency (~ 99%), good physiochemical stability, and acceptable hemolysis potential. The pharmacokinetic study in rats showed that Cmax of artemether and lumefantrine for the optimized lipid emulsions were significantly increased than the injectable solution, which was critical for rapid antimalarial activity. Furthermore, the AUC0-t of artemether and lumefantrine in the lipid emulsion group were 5.01- and 1.39-fold of those from the solution, respectively, suggesting enhanced bioavailability. With these findings, the developed lipid emulsion is a promising alternative parenteral therapy for the malaria treatment, especially for severe or complicated malaria.

Lithospheric effective elastic thickness (T-e), a proxy for plIate strength, is helpful for the understanding of subduction characteristics. Affected by curvature, faulting and magma activity, lithospheric strength near trenches should be weakened but some regional inversion studies have shown much higher T-e values along some trenches than in their surroundings. In order to improve T-e-estimation accuracy, here we discuss the long-wavelength effect of dynamic topography and gravity on T-e estimation by taking the Izu-Bonin-Mariana (IBM) Trench as a case study area. We estimate the long-wavelength influence of the density and negative buoyancy of the subducting slab on observed gravity anomalies and seafloor topography. The residual topography and gravity are used to map T-e using the fan-wavelet coherence method. Maps of T-e, both with and without the effects of dynamic topography and slab gravity anomaly, contain a band of high-T-e values along the IBM Trench, though these values and their errors are lower when slab effects are accounted for. Nevertheless, tests show that the T-e map is relatively insensitive to the choice of slab-density modelling method, even though the dynamic topography and slab-induced gravity anomaly vary considerably when the slab density is modelled by different methods. The continued presence of a high-T-e band along the trench after application of dynamic corrections shows that, before using 2-D inversion methods to estimate T-e variations in subduction zones, there are other factors that should be considered besides the slab dynamic effects on the overriding plate.

Hearing loss, which is regarded as a worldwide public health concern, lacks approved therapeutic strategies. Current drug candidates used to treat hearing loss commonly have low efficacy. To achieve the optimum drug efficacy, we designed a liposome system to preload a clinically approved, water-soluble drug, minocycline. Inspired by our previous research, we used a mitochondria-targeting tetrapeptide, SS-31, to modify the surface of liposomes. The results revealed that SS-31 modified, minocycline-loaded liposomes significantly increased hair cell survival against chronic exposure to gentamicin in a zebrafish model. The designed formulation maintained the activity of mechanotransduction channels in the hair cells, and thus did not result in any alteration in gentamicin uptake. This suggested that the protective efficacy of the liposomes was induced by modulating targets associated with cell death. Further studies are required to clarify the exact intracellular mechanism of the designed formulation and to determine its clinical benefits in patients with hearing dysfunction.

There is limited evidence on the association between socioeconomic status (SES) and autism in developing nations. The aim of this study was to examine this association among children aged 0-17 years in China. We obtained data from the Second National Sample Survey on Disability, and selected 616,940 children for analysis. Autism was ascertained according to the International Statistical Classification of Diseases, Tenth Revision. Multiple logistic regressions allowing for weights showed that children in middle-income and high-income families were less likely than their low-income peers to have autism, with an odds ratio of 0.60 (95%CI: 0.39, 0.93) and 0.44 (95%CI: 0.27, 0.72), respectively. Children in middle-education families had 63% (95%CI: 41%, 95%) odds of autism relative to their counterparts in low-education families. Stratified analyses found that all observed associations were only in male children, not in female children. In conclusion, children in families with socioeconomic disadvantage, in the form of lower family income and education, had greater risk of childhood autism.

In the field of energy harvesting and self-powered sensing, the universal equivalent circuit model of triboelectric nanogenerators (TENGs) is an important development tool for research and applications. Such a universal model of the current source is established to first order for the basic operating modes of a TENG, which provide the related theoretical models and electrical models used in simulation. The universal first-order equivalent circuit model demonstrates that the carrying capacity of a TENG separates into three regions of distinct output characteristics, namely, constant current, maximum power, and constant voltage. Moreover, employing electrometers, an electrometer and multimeters, and TENGs in series and parallel in successive experiments, we verify that the TENG can be considered a current source with a resistance of mega-ohms and a capacitance of nano-farads. Overall, our first-order model sets electrical standards for the internal circuit of the TENG and therefore provides theoretical guidance that lays the foundation for applications in high-performance supply and grid-connected power generation.

Enhancing oil recovery through emulsification is possible during both cold and hot production in the heavy oil process. Emulsion stability is the key issue controlling the success of this process; conventionally, surfactants were used to facilitate emulsification and improve emulsion stability, increasing the cost remarkably. This study promotes an alternative way to generate stable -Pickering- emulsions without using expensive surfactants, a method that will reduce the operational costs and thus favor the field application step of emulsification in heavy-oil recovery. Throughout the paper, we explored answers to the following questions: (1) What conditions (asphaltene content) allow asphaltenes to stabilize W/O emulsions? (2) What are optimal aqueous conditions (pH, salinity) for stable emulsions? (3) Can such emulsions stabilized by asphaltenes be formed in-situ in a porous medium and thus improve recovery? These questions were answered through glass vial tests under controlled experimental conditions and sandpack flooding experiments. Emulsion stability was evaluated through glass vial tests, and the emulsion structure and type were determined using an optical microscope. Furthermore, sand-pack flooding experiments were performed using the formulation which favored the formation of stable emulsions. The glass vial tests showed that the optimal asphaltene concentration was 0.5 wt% to stabilize water-in-oil (W/O) emulsions. And the emulsion stability improved with water pH. The optimal salinity of 1 wt% led to the most stable W/O emulsions. The sandpack flood experiments showed that highest oil recovery was achieved when the emulsions with an intermediate stability instead of the most emulsion stability were formed in-situ in the sandpacks, such as at pH = 10 condition. Finally, recommendations were made for choosing the optimal formulation to help improve heavy-oil recovery.

This paper investigates the joint optimization problem on the logistics infrastructure investment and CO2 emission taxes for a sustainable city logistics network design by a goal programming approach where the cost recovery, service level and CO2 emission reduction goals are involved. The above multi-objective logistics infrastructure capacity investment and CO2 emission taxes problem is formulated as a bi-level goal programming model. Given the priority structure of the goals, the total deviations from predetermined goals are minimized in the upper level, while the lower level of the model serves as the service route choice equilibrium problem of logistics users. To solve the proposed model, a genetic algorithm is developed, where the method of successive average (MSA) is embedded. The case study focusing on the urban logistics network of Changsha, China demonstrates the effectiveness of the bi-level goal programming model and the genetic algorithm. The findings reveal that the priority rankings of the goals have a significant impact on the joint decisions of CO2 emission taxes and logistics infrastructure capacity investment. The proposed methodology provides an avenue to balance multiple conflicting objectives and obtain an economical and environmental city logistics network.

Objective Air particulate matter (PM) pollution is associated with the alterations in circulating pulmonary damage proteins. But there are not consistent results among the epidemiological studies. The aim of this study is to investigate the alteration of surfactant protein (SP) from PM exposure. Methods We conducted a comprehensive meta-analysis by searching the databases of PubMed, Medline, EMBASE, Web of Science and CNKI before October 2020 which reported PM pollutants and surfactant protein in the population. The sources of heterogeneity were assessed by subgroup (smoking, particulate matter with different aerodynamic diameter, exposure duration) analysis. We also used the publication bias tests for the comprehensive assessment. Results This meta-analysis consisted of 10 studies with 1985 subjects. The results showed that the combined standardized mean difference (SMD) value was 0.05, 95% confidence interval (CI) was −0.07 to 0.17 for serum SP-A and −0.81 (95% CI: -1.41 to −0.21) for circulating SP-D. Among smokers, the combined SMD value of SP-A were 0.29 (95% CI: 0.05 to 0.52). We did not find the correlation between publication year of SP-A and SP-D and study heterogeneity. Conclusions Circulating SP-D was significantly decreased by air particulate matter. Serum SP-A was significantly increased by PM exposure among smokers. Circulating surfactant protein may be considered as a biomarker for respiratory injury caused by air particulate matter.

Background Adults with intellectual disabilities (ID) often have multiple comorbidities. Psychiatric disorders in this population have been poorly studied in developing countries. We aimed to investigate the prevalence of psychiatric disorders in adults with ID and whether comorbid psychiatric disorders were associated with health service utilisation. Methods We obtained data from the Second National Sample Survey on Disability, conducted in 31 provinces of China and selected a subsample of 13 631 adults aged 18 years and above with ID. ID were defined by intelligence quotient score under 70, deficits in two or more adaptive behaviours and age of onset under 18 years. Psychiatric disorders were identified according to the International Statistical Classification of Diseases, Tenth Revision. Logistic regressions were used for data analyses. Results The prevalence of psychiatric disorders in adults with ID was 16.7%. The most prevalent type of psychiatric disorder was dementia. Older adults, females, being minorities, urban residents, being literate, low-income groups and having severe ID, were associated with elevated risk of psychiatric disorder among adults with ID. Compared with individuals without psychiatric disorders, those with comorbid psychiatric disorders were more likely to use medical service and less likely to use rehabilitation service. Conclusions The prevalence of psychiatric disorder in adults with ID was strikingly higher than that in the general population. Health service utilisation among Chinese adults with ID remained a big challenge. There is a possibility of diagnostic overshadowing by local clinicians, which may have resulted in overdiagnosis of dementia and underdiagnosis of common mental disorders. This study informs further investigations regarding common mental disorders among people with ID and has implications for public health strategies and health policies to meet health service need for this population.

The hearing loss induced by aminoglycosides is caused by the permanent loss of mechanosensory hair cells of the inner ear. The aim of the present study is therefore to evaluate the protective effect of Bendavia, a novel antioxidant, on gentamicin-induced hair cell damage in zebrafish lateral lines. The results demonstrated the pretreatment of Bendavia exhibited dose-dependent protection against gentamicin in both acute and chronic exposure. We found that Bendavia at 150 μm conferred optimal protection from either acute or chronic exposure with ototoxin. Bendavia reduced uptake of fluorescent-tagged gentamicin via mechanoelectrical transduction channels, suggesting its protective effects may be partially due to decreasing ototoxic molecule uptake. The intracellular death pathways inhibition triggered by gentamicin might be also included as no blockage of gentamicin was observed. Our data suggest that Bendavia represents a novel otoprotective drug that might provide a therapeutic alternative for patients receiving aminoglycoside treatment.

PURPOSE To estimate the prevalence of, and association between, co-morbid visual and psychiatric disabilities among elderly (>65 years-of-age) persons in China. METHODS Random representative samples were obtained using multistage, stratified, cluster sampling, with probabilities proportional to size. Standard weighting procedures were used to construct sample weights that reflected this multistage, stratified cluster sampling survey scheme. Logistic regression models were used to elucidate associations between visual and psychiatric disabilities. RESULTS Among the Chinese elderly, >160,000 persons have co-morbid visual and psychiatric disabilities. The weighted prevalence among this cohort is 123.7 per 100,000 persons. A higher prevalence of co-morbid visual and psychiatric disabilities was found in the oldest-old (p

A 7-wk feeding trial was conducted to evaluate the effects of dietary Antarctic krill meal (AKM) on the growth performance, proximate composition of muscles, and antioxidative capacity of juvenile spotted halibut. Six diets were formulated to contain about 50% protein and 8% lipid. A control diet (R0) without AKM and the other five diets with 8.1, 16.2, 24.3, 32.4, and 42.5% AKM supplementation (R10–50) to replace 10, 20, 30, 40, and 50% fishmeal protein were used to feed to juvenile spotted halibut. The juveniles were fed with each diet using three replicates and cultivated in the indoor culture system. Results showed that the specific growth rate, feed intake, and protein efficiency ratio in the R30 and R40 groups were significantly higher than that in other groups (P

This paper proposes a multi-scale segmentation approach for high resolution remote sensing image (HRRSI) based on the gravitational field and region merging. In this approach, the HRRSI is firstly transformed into a gravitational field by incorporating the spatial and spectral information. Based on which, the attraction among neighboring pixels will cause travelling of each pixel. During the travelling, pixels with similar spectral information which are at the nearby location get grouped, which define an initial segmentation for the HRRSI which is often over-segmented in places. Then, an improved graph based region merging method is adopted to merge the over-segmented regions which yield the multi-scale segmentation results. To evaluate the proposed approach, we conduct extensive experiments on three HRRSIs from different sensors and the obtained results are compared with those of eCognition's multi-resolution segmentation method. The experimental results show that the proposed approach reduces much more over-segmentation problem and produces more accurate image segmentation.

Aim Cerebral palsy (CP) is the most common cause of motor impairment in childhood. This study aimed to examine the prevalence, severity and concurrent impairments of CP-related motor impairment among Chinese children. Methods Children with CP-related motor impairment aged 0–17 years were identified through a national population-based survey based on World Health Organization International Classification of Functioning, Disability and Health. Logistic regression models allowing for weights were used to examine individual and family factors in relation to CP-related motor impairment. Results The weighted prevalence of CP-related motor impairment was 1.25 per 1000 children (95% confidence interval (CI): 1.16, 1.35) in China. Male children, children in multiples and in families where adults suffered from CP, were more likely to be affected by CP-related motor impairment. For mild, moderate, severe and extremely severe groups of motor impairment, weighted proportions of CP were 14.12% (95%CI: 11.70, 16.95), 20.35% (95%CI: 17.48, 23.56), 27.44% (95%CI: 24.25, 30.87) and 38.09% (95%CI: 34.55, 41.76), respectively; and weighted proportions of concurrent visual, hearing and cognitive impairment were 5.00% (95%CI: 3.59, 6.91), 6.98% (95%CI: 5.34, 9.08) and 71.06% (95%CI: 67.57, 74.31), respectively. Conclusions Gender, multiple births and family adults with CP were significantly associated with CP-related motor impairment in Chinese children. Proportions of CP and concurrent impairments that increased with severity of motor impairment were observed.

Aminoglycoside-induced hearing loss stems from damage or loss of mechanosensory hair cells in the inner ear. Intrinsic mitochondrial cell death pathway plays a key role in that cellular dysfunction for which no proven effective therapies against oto-toxicities exist. Therefore, the aim of the present study was to develop a new mitochondrial targeting drug delivery system (DDS) that provided improved protection from gentamicin. Particularly, SS-31 peptide-conjugated geranylgeranylacetone (GGA) loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles were constructed successfully via emulsion-solvent evaporation method. The zebrafish lateral line sensory system was used as an in vivo evaluating platform to investigate the protective efficiency against gentamicin. SS-31 modification significantly reduced the activity of mechanoelectrical transduction (MET) channel and gentamicin uptake in zebrafish lateral line hair cells. As expected, SS-31 conjugated nanoparticles showed mitochondrial specific accumulation in hair cells when compared with unconjugated formulations. Furthermore, intracellular SS-31 modified PLGA NPs slightly enhanced mitochondrial membrane potential (MMP, ΔΨm) and then returned to a steady-state, indicating their effect on the respiratory chain complexes in mitochondria. GGA loaded SS-31 conjugated nanoparticles demonstrated the most favorable hair cells survivals against gentamicin when compared with unconjugated groups whereas blank formulations failed to exhibit potency, indicating that the efficiency was attributed to drug delivery of GGA. These results suggest that our constructed mitochondria-targeting PLGA based DDS have potential application in protecting hair cells from ototoxic agents.

GPS-derived horizontal velocities, geologic fault slip rates and earthquake-derived fault slip vector azimuths are inverted simultaneously for fault coupling and slip rate deficit on the Haiyuan-Liupanshan fault in the northeastern margin of the Tibetan Plateau. Along the Haiyuan fault, the results show 3.2–6.2 mm/yr of left-lateral strike-slip, and the strike-slip transformed into thrusting deformation (2.8–3.5 mm/yr) along the Liupanshan fault. The results suggest full coupling down to ∼10 km along the Haiyuan fault. Significant portions from the Jinqianghe fault to the Maomaoshan fault, however, are locked to ∼23 km depth. The abrupt change in fault coupling coincides with the Tianzhu seismic gap. High slip rate deficit (3.0–4.5 mm/yr) and seismic moment accumulation rate are also interpreted along the seismic gap. The Liupanshan fault is locked to 15–20 km depth. A high seismic moment accumulation rate, low slip rate deficit (2.0–3.2 mm/yr) and scarcity of large seismic event over the last 1400 years may imply high strain accumulation on the fault. The results demonstrate that crustal deformation in the northeastern Tibetan Plateau is dominated by elastic block rotation. We also conclude that deformation due to fault coupling is limited along the near-field (less than 50 km with velocities less than 2 mm/yr) of the Haiyuan-Liupanshan fault.

This study aimed to explore the role and possible mechanism of component I from agkistrodon acutus venom (AAVC-I) in promoting the apoptosis of oral squamous cell carcinoma (OSCC). HN4 cells (a human OSCC cell line) were randomly divided into four experimental groups: low AAVC-I (2.5 μg/mL) group, medium AAVC-I (5 μg/mL) group and high AAVC-I (10 μg/mL) group, as well as control group (AAVC-I, 0 μg/mL). AVVC-I was dissolved in RPMI-1640 medium and added to the culture wells at different concentrations when tumor cells had reached the logarithmic growth phase. After 24 hours, cells were harvested and the inhibitory rate of cell proliferation and the mitochondrial membrane depolarization were measured. Western blotting was used to detect the expression levels of cytochrome c, Bcl-2 associated X protein (Bax), and caspase-3 in the cellular cytoplasm either containing mitochondria or following the removal of mitochondria. Cellular apoptosis was detected by flow cytometry. Compared to the control group, AAVC-I treatment not only inhibited NH4 growth, but also upgraded the expression of caspase-3 in NH4 cells. Meanwhile, it was observed that Bax translocation to mitochondria and cytochrome c release into the cytosol increased in AAVC-I treatment. This indicated that AAVC-I could disrupt mitochondrial membrane depolarization and result in cellular apoptosis, and the apoptosis rate of NH4 increased with the concentration of AAVC-I. The data suggested that AAVC-I promotes the apoptosis of HN4 cells through the mitochondrial pathway in a dose-dependent manner, which provides experimental data and new ideas for future research and clinical treatment options for OSCC.

Background: Monocarboxylate Transporter 1 (MCT1), an important membrane transport protein, mediates the translocation of monocarboxylates together with protons across biological membranes. Due to its pathological significance, MCT1 plays an important role in the progression of some diseases, such as brain diseases and cancers. Methods: We summarize the general description of MCT1 and provide a comprehensive understanding of the role of MCT1 in brain diseases and cancers. Furthermore, this review discusses the opportunities and challenges of MCT1- targeting drug-delivery systems in the treatment of brain diseases and cancers. Results: In the brain, loss of MCT1 function is associated with pathologies of degeneration and injury of the nervous system. In tumors, MCT1 regulates the activity of signaling pathways and controls the exchange of monocarboxylates in aerobic glycolysis to affect tumor metabolism, proliferation and invasion. Meanwhile, MCT1 also acts as a good biomarker for the prediction and diagnosis of cancer progressions. Conclusion: MCT1 is an attractive transporter in brain diseases and cancers. Moreover, the development of MCT1- based small molecule drugs and MCT1 inhibitors in the clinic is promising. This review systematically summarizes the basic characteristics of MCT1 and its role in brain diseases and cancers, laying the foundation for further research on MCT1.

As the demand for nutrients in malignant proliferation of tumors increases, the L-type amino acid transporter 1(LAT1) and amino acid transporter B

To investigate the target blood pressure level of restrictive fluid resuscitation in patients with traumatic hemorrhagic shock.Sixty patients with traumatic hemorrhagic shock admitted to the First Affiliated Hospital of Bengbu Medical College from January 2016 to December 2018 were enrolled. All patients were resuscitated with sodium acetate ringer solution after admission. According to the difference of mean arterial pressure (MAP) target, the patients were divided into low MAP (60 mmHg ≤ MAP65 mmHg, 1 mmHg = 0.133 kPa), middle MAP (65 mmHg ≤ MAP70 mmHg) and high MAP (70 mmHg ≤ MAP75 mmHg) groups by random number table using the admission order with 20 patients in each group. Those who failed to reach the target MAP after 30-minute resuscitation were excluded and supplementary cases were deferred. The restrictive fluid resuscitation phase was divided into three phases: before fluid resuscitation, liquid resuscitation for 30 minutes and 60 minutes. The most suitable resuscitation blood pressure level was further speculated by monitoring the inflammatory markers and hemodynamics in different periods in each group of patients. Pearson correlation analysis was used to detect the correlation of variables.Before fluid resuscitation, there was no significant difference in hemodynamics or expressions of serum cytokines among the three groups. Three groups of patients were resuscitated for 30 minutes to achieve the target blood pressure level and maintain 30 minutes. With the prolongation of fluid resuscitation time, the central venous pressure (CVP), cardiac output (CO) and cardiac index (CI) were increased slowly in the three groups, and reached a steady state at about 30 minutes after resuscitation, especially in the high MAP group and the middle MAP group. The expressions of serum inflammatory factors in the three groups were gradually increased with the prolongation of fluid resuscitation time. Compared with the low MAP group and the high MAP group, after 30 minutes of resuscitation the middle MAP group was superior to the other two groups in inhibiting the expressions of pro-inflammatory factors tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and promoting anti-inflammatory factors IL-10 [TNF-α mRNA (2When patients with traumatic hemorrhagic shock received restrict fluid resuscitation at MAP of 65-70 mmHg, the effect of reducing systemic inflammatory response and improving hemodynamics is better than the target MAP at 60-65 mmHg or 70-75 mmHg. It is suggested that 65-70 mmHg may be an ideal target MAP level for restrictive fluid resuscitation.

The high interior heterogeneity of land surface covers in high-resolution image of coastal cities makes classification challenging. To meet this challenge, a Multi-Scale Superpixels-based Classification method using Optimized Spectral−Spatial features, denoted as OSS-MSSC, is proposed in this paper. In the proposed method, the multi-scale superpixels are firstly generated to capture the local spatial structures of the ground objects with various sizes. Then, the normalized difference vegetation index and extend multi-attribute profiles are introduced to extract the spectral−spatial features from the multi-spectral bands of the image. To reduce the redundancy of the spectral−spatial features, the crossover-based search algorithm is utilized for feature optimization. The pre-classification results at each single scale are, therefore, obtained based on the optimized spectral−spatial features and random forest classifier. Finally, the ultimate classification is generated via the majority voting of those pre-classification results in each scale. Experimental results on the Gaofen-2 image of Qingdao and WorldView-2 image of Hong Kong, China confirmed the effectiveness of the proposed method. The experiments verify that the OSS-MSSC method not only works effectively on the homogeneous regions, but also is able to preserve the small local spatial structures in the high-resolution remote sensing images of coastal cities.

To meet the demands of civil aviation and other precise navigation applications, several satellite-based augmentation systems (SBASs) have been developed around the world, such as the Wide Area Augmentation System (WAAS) for North America, the European Geostationary Navigation Overlay Service (EGNOS) for Europe, the Multi-functional Satellite Augmentation System (MSAS) for Japan, the GPS (Global Positioning System) Aided GEO Augmented Navigation (GAGAN) for India, and the System for Differential Corrections and Monitoring (SDCM) for Russia. The SBASs broadcast messages to correct satellite orbit, clock, and ionosphere errors to augment the GPS positioning performance. In this paper, SBAS orbit, clock and ionospheric corrections are evaluated. Specifically, the orbit, clock and ionospheric corrections derived from SBAS messages are comprehensively evaluated using data collected from the above mentioned systems over 181 consective days. The evaluation indicates that the EGNOS outperforms other systems with signal-in-space range error (SISRE) at 0.645 m and ionospheric correction accuracy at 0.491 m, respectively. Meanwhile, the accuracy of SDCM is comparable to EGNOS with SISRE of 0.650 m and ionospheric correction accuracy of 0.523 m. For WAAS, the SISRE is 0.954 m and the accuracy of ionospheric correction is 0.505 m. The accuracies of the SBAS corrections from the MSAS and GAGAN systems, however, are significantly worse than those of others. The SISREs are 1.931 and 1.325 m and the accuracies of ionospheric corrections are 0.795 and 0.858 m, for MSAS and GAGAN, respectively. At the same time, GPS broadcast orbit, clock and ionospheric corrections are also evaluated. The results show that there are no significant improvements in the SISRE of the broadcast navigation data by applying SBAS corrections. On the other hand, the accuracy of SBAS ionospheric corrections is still much better than GPS broadcast ionospheric corrections, which could still be beneficial for single-frequency users.

Iron not only plays an important role in the physiological function of organisms but also is an essential nutrient for the growth of pathogens. There is a competing relationship between organisms and pathogens for the use of iron in the case of infection. The macrophage, as the first immune cell found to participate in iron metabolism, has a precise regulation system to maintain iron homeostasis in response to pathogen infection. However, few studies have compared the effects of different types of bacterial infections on the iron homeostasis of macrophages. In this study, we investigated the changes in the iron regulation of the macrophage 3D4/2 by the infection of the extracellular bacterium Escherichia coli K88 (E. coli K88) and the intracellular bacterium Salmonella typhimurium (S. typhimurium). We found that S. typhimurium infection reduced the uptake of extracellular iron, promoted the outflow transport of intracellular iron, and decreased the free iron ions for intracellular bacterial proliferation and utilization. However, the infection of E. coli K88 reversed iron regulation by promoting the uptake of extracellular iron, reducing the extracellular transport of intracellular iron and increasing the storage of iron in 3D4/2. The results demonstrated that macrophages had completely opposing regulations of iron metabolism in response to intracellular and extracellular bacteria. It suggested that the diversion of cellular iron traffic would be considered as an important defense mechanism for macrophages to reduce iron availability for bacteria, and the resistance of iron spread or the interruption of the assimilation of iron by bacteria would be beneficial in developing therapeutics for bacterial infection.

Linking deep seismic profiles with regional-scale gravity inversion is a powerful tool to deduce the architecture of rifted margins and their structural evolution. Here we map upper and lower crustal thicknesses of the northern South China Sea (SCS) margin in order to investigate the occurrence of depth-dependent crustal extension from the proximal to the distal margin. By comparing upper and lower crustal stretching factors, we find that the northern margin of the SCS is segmented in three parts: (1) sedimentary basins where upper crust is stretched more than lower crust, (2) distal margin where lower crust is stretched more than upper crust, (3) mostly proximal margin regions where the two layers have similar stretching factors. Our results suggest that sedimentary basins and distal margin prominently feature depth-dependent extension, however accommodated by different processes. While differential thinning within sedimentary basins appears to be governed by lateral pressure variations inducing lower crustal flow, we suggest the distal margin to be affected by a combination of mantle flow-induced lower crustal shearing and sequential fault activity during crustal hyper-extension.

Global navigation satellite system/acoustic (GNSS/A) underwater positioning technique has drawn increasing attention in the fields of marine scientific research and engineering application. The conventional positioning strategy of GNSS/A is to fix the positions of sea-surface transducer, in other words, the positions of the transducer determined by GNSS positioning at different epochs are regarded as accurate and unbiased, and then estimate the underwater transponder's coordinate with acoustic ranging data. However, there inevitably exists bias in the estimation of transducer's positions, and the precision varies at different epochs. Ignoring precision differences of the transducer's positions will lead to a worse estimation of the transponder's coordinate. In this contribution, we propose a total adjustment (TA) method, where the positions of both sea-surface transducer and seafloor transponder are treated as unknown parameters, and the transducer's positions determined by GNSS positioning at different epochs are introduced as virtual observations. In order to reduce the computation load caused by large increase of estimation parameters, an equivalent transformation is applied to observation equations to remove estimation parameters for the transducer's positions at different epochs. To evaluate the performance of the proposed total adjustment method, a series of simulation tests and a sea-trail experiment were carried out. Testing results show that, as compared with the traditional method, the positioning accuracy with the proposed method can be improved by about 10%–33% in the simulation tests and 15% in the field test.

Activating naturally occurring nanoparticles in the reservoir (clays) to generate Pickering emulsions results in low-cost heavy oil recovery. In this study, we test the stability of emulsions generated using different types of clays and perform a parametric analysis on salinity, pH, water to oil ratio (WOR), and particle concentration; additionally, we report on a formulation of injected water used to activate the clays found in sandstones to improve oil recovery. First, oil-in-water (O/W) emulsions generated by different clay particles (bentonite and kaolinite) were prepared for both bottle tests and zeta potential measurements, then the stability of dispersion was measured under various conditions (pH and salinity). Heavy crude oils (50 to 170,000 cP) were used for all experiments. The application conditions for these clay types on emulsion generation and stability were examined. Second, sandpacks with known amounts of clays were saturated with heavy-oil samples. Aqueous solutions with various salinity and pH were injected into the oil-saturated sandpack with a pump. The recoveries were monitored while analyzing the produced samples; a systematic comparison of emulsions formed under various conditions (e.g., salinity, pH, WOR, clay type) was presented. Third, glass bead micromodels with known amounts of clays were also prepared to visualize the in-situ behavior of clay particles under various salinity conditions. The transparent mineral oil instead of opaque heavy oil was used in these micromodel tests for better visualization results. Recommendations were made for the most suitable strategies to enhance heavy oil recovery with and without the presence of clay in the porous medium; moreover, conditions and optimal formulations for said recommendations were presented. The bottle tests showed that 3% bentonite can stabilize O/W emulsions under a high WOR (9:1) condition. The addition of 0.04% of NaOH (pH=12) further improved the emulsion stability against salinity. This improvement is because of the activation of natural surfactant in the heavy oil by the added alkali—as confirmed by the minimum interfacial tension (0.17 mN/M) between the oil and 0.04% of the NaOH solution. The sandpack flood experiments showed an improved sweep efficiency caused by the swelling of bentonite when injecting low salinity fluid (e.g., DIW). The micromodel tests showed a wettability change to be more oil-wet under high salinity conditions, and the swelling of bentonite would divert incoming water flow to other unswept areas thus improving sweep efficiency. This paper presents new ideas and recommendations for further research as well as practical applications to generate stable emulsions for improved waterflooding as a cost-effective approach. It was shown that select clays in the reservoir can be activated to act as nanoparticles, but making them generate stable (Pickering) emulsions in-situ to improve heavy-oil recovery requires further consideration.

Island arc magmatism is considered a major mechanism of continental crustal growth; hence, the variation in island arc magma production rates and its influencing factors are of great importance. The along-arc strike variation in the island arc magma production rate is important for elucidating whether the subduction zone temperature is a controlling factor on arc magmatism. No back-arc spreading or ridge subduction is occurring in the intraoceanic subduction region of the Aleutian subduction zone, and the along-arc temperatures vary due to differences in the subducting plate age, convergence rate, and slab dip. Therefore, this is an ideal region to study the correlation between magma production rates and subduction zone temperatures. However, previous studies estimated the magma production rates at only a few locations due to the insufficient coverage of seismic data. Here, we employ the gravity inversion method based on density modelling and seismic data constraints to calculate the present-day arc crustal thickness and then obtain the magmatic thickness by removing the pre-existing crustal thickness from the present-day arc crustal thickness. Finally, the magma production rates along the main intraoceanic subduction region of the Aleutian Arc are mapped by estimating the island arc magmatic thickness and the most recent subduction inception dating result. In addition, the subduction zone temperatures and mantle melt amounts along five profiles across the Aleutian Arc are calculated. The magma production rate variation is highly correlated with the mantle melt amount. The slab temperature controls the extent of the slab dehydration, which is essential for mantle wedge melting, and the mantle wedge temperature controls the size of the hydrated mantle melting region and the melting fraction therein. Therefore, as the subduction zone temperature controls the mantle melt amount, we suggest that the subduction zone temperature is the first-order controlling factor on the magma production rate.

Multi-objective optimization (MOO) is an important research topic in both science and engineering. This paper proposes a diversity-enhanced and memory-based multi-objective gravitational search algorithm (DMMOGSA). We combine the memory of the best states of individual particles and their population in their evolution paths and the gravitational rules to construct a new search strategy. Under this strategy, the position and mass states of each particle are updated based on the memory associated with it and the current states of all particles in the current population in terms of their gravitational forces on it. A novel diversity-enhancement mechanism is also employed to control the velocity of each particle for traveling to a new position. Experiments were conducted on 12 well-known benchmark functions, and for each function the results of DMMOGSA were compared with those of SPEA2, NSGA-II and MOPSO. Our results show that DMMOGSA can reduce the effect of premature convergence and achieve more reliable performance on most of the tested cases.

Graphical abstractDisplay Omitted The multi-level thresholding is a popular method for image segmentation. However, the method is computationally expensive and suffers from premature convergence when level increases. To solve the two problems, this paper presents an advanced version of gravitational search algorithm (GSA), namely hybrid algorithm of GSA with genetic algorithm (GA) (GSA-GA) for multi-level thresholding. In GSA-GA, when premature convergence occurred, the roulette selection and discrete mutation operators of GA are introduced to diversify the population and escape from premature convergence. The introduction of these operators therefore promotes GSA-GA to perform faster and more accurate multi-level image thresholding. In this paper, two common criteria (1) entropy and (2) between-class variance were utilized as fitness functions. Experiments have been performed on six test images using various numbers of thresholds. The experimental results were compared with standard GSA and three state-of-art GSA variants. Comparison results showed that the GSA-GA produced superior or comparative segmentation accuracy in both entropy and between-class variance criteria. Moreover, the statistical significance test demonstrated that GSA-GA significantly reduce the computational complexity for all of the tested images.

Gravitational search algorithm (GSA) has been successfully applied to many scientific and engineering applications in the past few years. In the original GSA and most of its variants, every agent learns from all the agents stored in the same elite group, namely Kbest. This type of learning strategy is in nature a fully-informed learning strategy, in which every agent has exactly the same global neighborhood topology structure. Obviously, the learning strategy overlooks the impact of environmental heterogeneity on individual behavior, which easily resulting in premature convergence and high runtime consuming. To tackle these problems, we take individual heterogeneity into account and propose a locally informed GSA (LIGSA) in this paper. To be specific, in LIGSA, each agent learns from its unique neighborhood formed by k local neighbors and the historically global best agent rather than from just the single Kbest elite group. Learning from the k local neighbors promotes LIGSA fully and quickly explores the search space as well as effectively prevents premature convergence while the guidance of global best agent can accelerate the convergence speed of LIGSA. The proposed LIGSA has been extensively evaluated on 30 CEC2014 benchmark functions with different dimensions. Experimental results reveal that LIGSA remarkably outperforms the compared algorithms in solution quality and convergence speed in general.

With the development of multi-constellation Global Navigation Satellite Systems (GNSS), more and more navigation satellites are available for position determination. Although the increased number of visible satellites can improve the positioning performance, the computational load to track and process signals from all visible satellites will increase significantly. In practical applications particularly using mobile devices powered by batteries of limited capacity, it will be desirable to track and process only satellite signals that are necessary to meet given accuracy requirement. This requires the development of appropriate satellite selection algorithms. A new satellite selection algorithm with a controllable Weighted Positioning Dilution Of Precision (WPDOP) threshold is developed in this paper. The new approach can be used to select any number of visible satellites with respect to given positioning accuracy. Numerical computations with multi-constellation GNSS data were conducted to assess the perfo...

The distribution of urban impervious surface is a significant indicator of the degree of urbanization, as well as a major indicator of environmental quality. Hence, taking advantage of remotely sensed imagery to map impervious surface has become an important topic. Spectral indices have been developed due to its convenience to apply, among which feature extraction approach has shown superiority in reliability and applicability. However, impervious surface is often confused with bare soil when the current existing indices are used as well as their sensor-specific limitations. In this study, a new index, combinational build-up index (CBI), is proposed to extract impervious surface. The new index combines the first component of a principal component analysis (PC1), normalized difference water index (NDWI), and soil-adjusted vegetation index (SAVI), representing high albedo, low albedo, and vegetation, respectively, to reduce the original bands into three thematic-oriented features. The new index was tested using various remote sensing images at different spectral and spatial resolutions. Qualitative and quantitative assessments of the accuracy and separability of CBI, together with the comparison with other existing indices, were performed. The result of this study indicates that the proposed method is able to serve as an effective impervious index and can be applied widely.

The spatial pattern and rate of strain accumulation on a fault during the pre- and inter-seismic phases are very important for interpreting the mechanism of earthquakes and evaluating seismic potentials. Here we use global positioning system (GPS) data and the block-dislocation model to invert for the locking degree and slip rate deficit of the Main Himalayan Thrust (MHT) fault in the southern margin of Tibet before the 2015 Mw 7.9 Nepal earthquake. Results show that the locking depth and slip rate deficit increase from the west to the east. Along the western segment of the MHT fault (80°E–84°E), the locking depth is estimated to be 12–17 km with a slip rate deficit of 0–5 mm/a; along the central Nepal segment (84°E–87°E), the locking depth is 16–21 km with a slip rate deficit of 6–10 mm/a, whilst along the eastern segment (87°E–90°E), the locking depth increases to 23–26 km with a slip rate deficit of 8–13 mm/a. The 2015 Nepal earthquake initiated at the boundary between the western and central segments, an area with as where the slip rate deficit varies dramatically from 0 to 9 mm/a within 50 km resulting in high energy gradients. High strain concentration along the central and eastern segments leads to unilateral propagation of the rupture to the east. Given the paucity of large seismic events over the previous decades and the current high slip rate deficit, seismic hazard on the eastern Nepal segment remains high.

Cycle slip detection and correction is very important for high-precision positioning with GNSS. In past research, a lot of work has been done on this subject, especially for current dual-frequency GPS (the global positioning system). However, few have been done about the reliability. Similarly to ambiguity resolution, reliability is important to cycle slip detection and correction. In this research work, methods on how to assess and ensure the reliability of cycle slip detection and correction are proposed.

Controlling the specific ionic interactions between drugs and mesophases particles can enable controlled release systems for proteins. Here we present the interaction of basic nerve growth factor (NGF) with highly homogeneous cubosomes based on the glycerol monooleate–water system where β-casein was employed as a stabilizer. Addition of β-casein leads to modification of the internal cubosomal surface to generate highly negative charge. The colloidal structures were characterized with small angle X-ray scattering and visualized using cryogenic transmission electron microscopy. These nanostructured particles are able to sustain the release of hydrophilic NGF since less than 15% of the protein was released over 24 h. Similarly, cationic 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) immobilized within the mesophase particles provided another specific interactions of the cubosomal surface, from which the release of water soluble bovine serum albumin was retarded. Evaluation of NGF entrapped colloidal dispersions in PC12 cells led to identification of β-casein stabilized cubosomes that induce more than 140% neurite outgrowth enhancing the activity of NGF. Accordingly, the AUC value for RWM administration of NGF-loaded dispersions in guinea pigs was significantly higher than that administrated with NGF, of which the relative bioavailability of the β-casein stabilized dispersions was increased to 337% as compared with free drug.

Gold nanoparticles demonstrate developmental toxicity in a shape dependent manner. In a zebrafish model, gold nanospheres exhibit more toxicity when compared with nanorods and nanopolyhedrons. After storage, nanopolyhedrons elicit obvious lethality. We believe that the results from this investigation could be used to track the toxicity of living organisms.