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Abstract Modulation of scattering in random lasers (RLs) by magnetic fields has attracted much attention due to its rich physical insights. We fabricate magnetic gain polymer optical fiber to generate RLs. From macroscopic experimental phenomena, with the increase of the magnetic field strength, the magnetic transverse photocurrent exists in disordered multiple scattering of RLs and the emission intensity of RLs decreases, which is the experimental observation of photonic Hall effect (PHE) and photonic magnetoresistance (PMR) in RLs. At the microscopic level, based on the field dependence theory of magnetic disorder in scattered nanoparticles and the replica symmetry breaking theory, the magnetic-induced transverse diffusion of photons reduces the scattering disorder, and then decreases the intensity fluctuation disorder of RLs. Our work establishes a connection between the above two effects and RLs, visualizes the influence of magnetic field on RL scattering at the microscopic level, which is crucial for the design of RLs.

Abstract Northeast China is the main food production base of China. Extreme precipitation (EP) events can seriously impact agricultural production and socioeconomics, but the understanding of EP in Northeast China is still limited. In this study, using the non-stationary generalized extreme value (GEV) model, we investigate the trend and potential risk of EP in Northeast China during 1959–2017, especially in early and mid-summer (periods of high frequency of EP). Then, the relationships between EP and large-scale circulation over Northeast China in early and mid-summer are analyzed separately. The EP in Northeast China mainly presents positive trends in early summer but negative trends in mid-summer. Meanwhile, the EP with all the return periods presents apparently increasing trends in early summer, corresponding to more frequent EP events. Nevertheless, in mid-summer, the EP with 2-year return period decreases with location parameter, and the EP with 20-year, 50-year, and 100-year return periods slightly increases with scale parameter. The EP with 2-year return period occurs frequently in Liaoning Province, while the EP with 100-year return period is more likely to occur in Jilin Province and Heilongjiang Province. Moreover, the increase of the EP in early summer is mainly influenced by the northeast cold vortex; the effect of cold air on the EP is stronger in mid-summer, giving a clear explanation why the EP in mid-summer does not increase significantly. Overall, the outcomes of this study would be beneficial for the disaster prevention and mitigation in Northeast China.

Improving the nitrogen and phosphorus removal rates and efficiently controlling membrane fouling are the keys to fully exploiting the applicability of anaerobic membrane bioreactor (AnMBR) process in high-concentration wastewater treatment. To that purpose, an integrated reactor composed of an anaerobic ceramic membrane bioreactor and N anaerobic fluidized bed (AnCMBR-AFB) was built and pollutant removal efficiency, nitrogen and phosphorus recovery characteristics, and membrane pollution features of this integrated reactor were investigated. The results revealed that the integrated reactor had good pollutant removal efficiency, with turbidity, chromaticity, and UV254 average values of the effluent being 0.470 NTU, 0.011 A, and 0.057 cm−1, respectively, and the average CODCr removal rate was 80%. The nitrogen and phosphorus recoveries were significantly higher than the nitrogen and phosphorus removal rates of conventional AnMBR at 23.20 ± 1.17% and 43.34 ± 1.54%, respectively. Microscopic analysis revealed the formation of magnesium ammonium phosphate (MAP) crystals on the carrier's surface, and friction between the carrier and the membrane surface could delay membrane fouling while allowing the contaminated membrane surface to retain significant roughness. Membrane fouling was mostly brought on by amides and saturated hydrocarbons, and inorganic metal ions also played a role to some extent. HIGHLIGHTS Pollutant removal during the operation of the AnCMBR-AFB-integrated reactor.; The AnCMBR-AFB-integrated reactor recovers nitrogen and phosphorus by the MAP crystallization process higher than AnMBR.; Membrane fouling is decreased by the friction between the fluidized carrier and the ceramic membrane.;

Abstract The compaction quality of subgrade filler strongly affects subgrade settlement. The main objective of this research is to analyze the macro- and micro-mechanical compaction characteristics of subgrade filler based on the real shape of coarse particles. First, an improved Viola–Jones algorithm is employed to establish a digitalized 2D particle database for coarse particle shape evaluation and discrete modeling purposes of subgrade filler. Shape indexes of 2D subgrade filler are then computed and statistically analyzed. Finally, numerical simulations are performed to quantitatively investigate the effects of the aspect ratio (AR) and interparticle friction coefficient (μ) on the macro- and micro-mechanical compaction characteristics of subgrade filler based on the discrete element method (DEM). The results show that with the increasing AR, the coarse particles are narrower, leading to the increasing movement of fine particles during compaction, which indicates that it is difficult for slender coarse particles to inhibit the migration of fine particles. Moreover, the average displacement of particles is strongly influenced by the AR, indicating that their occlusion under power relies on particle shapes. The displacement and velocity of fine particles are much greater than those of the coarse particles, which shows that compaction is primarily a migration of fine particles. Under the cyclic load, the interparticle friction coefficient μ has little effect on the internal structure of the sample; under the quasi-static loads, however, the increase in μ will lead to a significant increase in the porosity of the sample. This study could not only provide a novel approach to investigate the compaction mechanism but also establish a new theoretical basis for the evaluation of intelligent subgrade compaction.

This paper aims to explore the coarse-grained rearrangement (CGR) phenomenon and its effect on the mechanical behaviors of high-speed railway graded aggregate (HRGA) materials during vibratory compaction. Firstly, the evolution of CGR is characterized by the analysis of mechanical behaviors and migration of the coarse grains in the HRGA materials. Then, a new indicator, the fraction of horizontally deflected coarse grains Hr, is proposed to evaluate the CGR, which increases with the rearrangement degree during vibratory compaction. Finally, using the discrete element method (DEM), the evolution of macro and micro mechanical properties of HRGA materials with different Hr-values (Hr = 0, 0.2, 0.4, 0.6, 0.8, and 1.0) are analyzed based on triaxial compression tests. The numerical results show that the shear strength of the assembly firstly increases with Hr and then reaches a plateau when Hr ≥ 0.6, which can be considered as the vibratory compaction steady state. For the microscopic behaviors, with Hr increasing, the enhanced interlocking between coarse particles makes it more difficult for them to rotate, leading to an increased proportion of sliding contact. Moreover, the effectiveness of the state of Hr = 0.6 was validated by the X-ray computed tomography (X-CT) scanning test. This research is expected to provide microscopic insights into the formation of internal structures for HRGA materials during vibratory compaction and provide a new method to assess the compaction quality of gravel fillers.

The essence of vibratory compaction of high-speed railway graded aggregate (HRGA) materials lies in both internal particle rearrangement and breakage. However, there is a research gap on the level of particle rearrangement and breakage effects on the vibratory compaction characteristics. A novel index, the breakage contribution rate Cb, was proposed to quantify the contribution level of particle breakage to vibratory compaction characteristics based on theoretical derivation. Additionally, the relationship between the gradation, maximum dry density (MDD) and Cb was established using a high-performance machine learning (ML) model. Finally, the impact of Cb on vibratory compaction characteristics under different compaction conditions, including vibration parameters, container size, and sample thickness, was explored through laboratory vibratory compaction tests (LVCTs). The results show that the Cb is better predicted by the PSO-ANN-ML model (the comprehensive evaluation index in the testing set is 4.028). Under different compaction conditions, Cb has a significant important effect on determining the actual dry density (ADD). When Cb> 8.8%, it may lead to over-compaction, which has a negative effect on the overall quality of the compacted structure. Based on the analysis of Cb and ADD, it is recommended that the vibratory frequency should be set to the inherent frequency of the sample, while the ratio of excitation force to static load should be controlled at 1.8. The ratio of the container diameter and the sample thickness to the maximum particle size of the sample should be controlled at 4.4 and 3.5, respectively. The breakage contribution rate index proposed in the study has significant implications for the control of compaction quality and the understanding of the compaction mechanism.

ABSTRACTGestational diabetes mellitus (GDM) is characterized by the development of hyperglycemia and insulin resistance during the second or third trimester of pregnancy, associated with considerable risks to both the mother and developing fetus. Although emerging evidence suggests an association between the altered gut microbiota and GDM, remarkably little is known about the microbial and metabolic mechanisms that link the dysbiosis of the gut microbiota to the development of GDM. In this study, a metagenome-wide association study and serum metabolomics profiling were performed in a cohort of pregnant women with GDM and pregnant women with normal glucose tolerance (NGT). We identified gut microbial alterations associated with GDM and linked to the changes in circulating metabolites. Blood metabolite profiles revealed that GDM patients exhibited a marked increase in 2-hydroxybutyric acid and L-alpha-aminobutyric acid, but a decrease in methionine sulfoxide, allantoin, and dopamine and dopaminergic synapse, when compared with those in NGT controls. Short-chain fatty acid-producing genera, including Faecalibacterium, Prevotella, and Streptococcus, and species Bacteroides coprophilus, Eubacterium siraeum, Faecalibacterium prausnitzii, Prevotella copri, and Prevotella stercorea, were significantly reduced in GDM patients relative to those in NGT controls. Bacterial co-occurrence network analysis revealed that pro-inflammatory bacteria were over-represented as the core species in GDM patients. These microbial and metabolic signatures are closely associated with clinical parameters of glucose metabolism in GDM patients and NGT controls. In conclusion, we identified circulating dopamine insufficiency, imbalanced production of SCFAs, and excessive metabolic inflammation as gut microbiota-driven multiple parallel hits linked to GDM development. This work might explain in part the mechanistic link between altered gut microbiota and GDM pathogenesis, and suggest that gut microbiota may serve as a promising target to intervene in GDM.

The land surface of a watershed acts as a large reservoir, with its catchment water storage capacity (CWSC) influencing rainfall-runoff relationship. Estimating CWSC at global grid scale is challenging due to calibration complexity, limited spatial continuity, and data scarcity. To address this, a deep learning-based approach incorporates spatial reconstruction and temporal transfer for capturing spatio-temporal variations in watershed characteristics. The study focuses on the Global Runoff Data Centre dataset and presents a grid-based hydrological model. Findings demonstrate accurate identification of CWSC distribution, with the model achieving an R ^2 of 0.92 and the runoff Kling–Gupta efficiency of 0.71 during validation. According to the CMIP6 projections, the global CWSC is anticipated to undergo a significant increase at a rate of 1.7 mm per decade under the SSP5-8.5 emission scenario. Neglecting spatio-temporal CWSC variability globally overestimates climate change’s impact on runoff, potentially reducing the projected long-term increase by up to 41%.

Diabetes patients need to monitor blood glucose all year round. In this article, a novel scheme is proposed for blood glucose detection. The proposed sensor is based on a U-shaped microfiber prepared using hydrogen-oxygen flame-heating technology, and then 3-aminopropyltriethoxysilane (APTES) and glucose oxidase (GOD) are successively coated on the surface of the U-shaped microfiber via a coating technique. The glucose reacts with the GOD of the sensor surface to produce gluconic acid, which changes the effective refractive index and then shifts the interference wavelength. The structure and morphology of the sensor were characterized via scanning electron microscope (SEM) and confocal laser microscopy (CLM). The experimental results show that the sensitivity of the sensor is as high as 5.73 nm/(mg/mL). Compared with the glucose sensor composed of the same material, the sensitivity of the sensor increased by 329%. The proposed sensor has a broad application prospect in blood glucose detection of diabetic patients due to the advantages of miniaturization, high sensitivity, and good stability.

Abstract Daily inflow forecasting is of vital importance in reservoir economic operation. In the context of hydrometeorological forecasting, the effectiveness of the data‐driven models has been demonstrated as bias correctors for physically‐based models or direct forecasting models. However, existing studies only highlight the performance improvements provided by the data‐driven model, lacking a comprehensive investigation on whether the data‐driven model should be used as bias correctors or direct forecasting models. This study constructs long short‐term memory (LSTM)‐based preprocessing and postprocessing techniques for a hydrological model, which are tested by linear scaling preprocessing and autoregressive (AR) postprocessing models. The integrated model is compared with the LSTM‐only model. The Shuibuya and Zuojiang reservoirs in China are selected as case studies. Results indicate that: (1) LSTM‐based bias correctors are effective in both preprocessing and postprocessing and (2) the integrated model is comparable to the LSTM‐only model when trained with four or more years of data, while it is better than the LSTM‐only model when trained with less data. These findings demonstrate that data‐driven methods can effectively correct the bias in physically‐based model output, and integrating the physical and data‐driven models is useful in improving multi‐step ahead reservoir inflow forecasting if limited data can be obtained.

Floquet topological insulators (FTIs) have richer topological properties than static systems. In this work, we designed different domain wall (DW) structures consisting of a Floquet photonic lattice with opposite helical directions. We investigated the existence and types of edge states in three shared coupling structures and the impact of these shared coupling structures on edge states. When two opposite helical lattices share a straight waveguide array coupling, the edge states are localized on the straight waveguide. When two opposite helical lattices share a clockwise (or anticlockwise) helical waveguide array coupling, the DWs consist of zigzag and bearded edges, but the positions of the zigzag and bearded edges of the shared clockwise waveguide array are different from those of the shared anticlockwise waveguide array. The slope and transmission rate of the edge states both vary with the degree of coupling between the shared waveguides. The characteristics of these edge states, such as transmission speed and band gap width, are also affected by the incidence angle, modulation phase factor, and helical radii, and the methods for controlling the edge states in different shared coupling structures are provided. This will help deepen our understanding of how topological structures influence the electronic and photonic properties of materials. This could also lead to combining topology with metasurface-based structured light, which would highlight many novel properties with great application potential for various fields, such as imaging, metrology, communication, quantum information processing, and light–matter interaction.

Abstract There are many kinds of materials or methods used to make optical microcavities, and they have many different geometric structures. And electrospinning technique has become a very convenient and easy one to prepare polymer fiber. Based on this situation, PM597-doped polymer solution was prepared into high-performance fibers with different diameters by electrospinning technology in our work. In order to better study the temperature sensing of polymer fiber whispering gallery mode, we have placed it on two different substrates with gold and aluminum. A 532 nm pulsed laser beam was used to excite a single fiber in the radial direction, then the whispering gallery mode (WGM) laser was observed and the distribution of WGM was determined by theoretical calculations. The threshold of samples on aluminum substrate is 0.4 μJ. In addition, it is found that the samples on aluminum substrate performed better in temperature sensing, and the value is 0.13 nm/°C. As a result, WGM polymer fiber microcavities on aluminum substrate made by electrospinning technology have very broad development prospects in biosensing, optical pump lasers and other applications.

Abstract Background Long noncoding RNA NEAT1 has been implicated in glioma progression. However, the effect of NEAT1 on glycolysis of glioma cell and the potential mechanism remain unclear. Methods In vitro experiments, including CCK-8, colony formation, ECAR, and lactate detection assays were performed to evaluate the effect of NEAT1 on proliferation and glycolysis of glioma cell. RNA pulldown and RIP assays were performed to identify the interaction between NEAT1 and PGK1. Truncated mutation of NEAT1 and PGK1 was used to confirm the specific interactive domains between NEAT1 and PGK1. Animal studies were performed to analyze the effect of NEAT1/PGK1 on glioma progression. Results NEAT1 knockdown significantly suppressed the proliferation and glycolysis of glioma cells. NEAT1 could specifically interact with PGK1, which promotes PGK1 stability. Hairpin A of NEAT1 is essential for interaction with M1 domain of PGK1. Depletion of NEAT1 markedly inhibited tumor growth in mice, while PGK1 could reverse this effect. Higher expression of NEAT1 was associated with poor overall survival of GBM patients. Conclusions NEAT1 over expression promotes glioma progression through stabilizing PGK1. NEAT1/PGK1 axis is a candidate therapeutic target for glioma treatment.

BackgroundNitrous oxide (N2O) is an increasingly popular recreational drug. N2O irreversibly disturbs the metabolism of vitamin B12, resulting in a functional deficiency. Vitamin B12 is vital for myelin synthesis and its deficiency primarily produces neurological complications. Inhaling N2O is more common and neurological complications are more evident than before.Case presentationWe report a young man who developed progressive limb numbness and unsteady walking after N2O abuse. The dominant diagnosis was subacute combined degeneration of the spinal cord (SCD). The patient was admitted to the hospital and given adenosylcobalamin treatment, but his symptoms progressed significantly from before and he developed acute cognitive impairment. After methylprednisolone combined with vitamin B12 treatment, symptoms significantly improved.ConclusionClinicians need to understand the presentation and treatment of SCD caused by N2O abuse. When symptoms progress despite conventional vitamin B12 therapy, the combination of methylprednisolone and vitamin B12 may be considered.

To evaluate the performance of expanded non-invasive prenatal testing (expanded noninvasive prenatal testing, NIPT-Plus) in screening for fetal chromosomal abnormalities includes aneuploidies and copy number variations, a total of 23,116 pregnant women with a singleton pregnancy were recruited for NIPT-Plus. Screening positive results were verified by karyotype analysis and chromosomal microarray analysis after amniocentesis. A total of 264 pregnancies (1.14%) were positive results as predicted by NIPT-Plus, including 233 aneuploidies and 31 copy number variations. Following genetic counseling, 233 (88.26%) pregnant women underwent invasive prenatal diagnosis and 136 were verified as true positives, comprising 72 common trisomies (T21, T18, T13), 47 sex chromosomal abnormalities two rare autosomal aneuploidies (RATs) and 15 copy number variations The positive predictive value for common trisomies, SCAs, RATs and CNVs were 68.57%, 68.12%, 6.67% and 51.72%, respectively. Pregnant women with screen-positive results for common trisomies have higher rates of invasive prenatal diagnosis and pregnancy termination than those with positive results for SCAs, RATs, and CNVs. NIPT-Plus showed a good performance in detecting common trisomies, SCAs and also contributed to detecting pathogenic CNVs, but higher accuracy was required in the detection of RATs. In summary, this study provides a reference for the clinical application of NIPT-Plus for screening fetal chromosomal abnormalities in this region. Therefore, we suggest that NIPT-Plus could be widely used in clinical screening for fetal chromosomal abnormalities in combination with prenatal diagnosis and genetic counseling.

Background: Hyperphenylalaninemia (HPA) is the most common inborn error in amino acid metabolism. It can be primarily classified into phenylalanine hydroxylase (PAH) deficiency and tetrahydrobiopterin (BH4) deficiency. BH4 deficiency (BH4D) is caused by genetic defects in enzymes involved in the biosynthesis and regeneration of BH4. 6-pyruvoyl-tetrahydropterin synthase (PTPS/PTS), which is encoded by the PTS gene, participates in the biosynthesis of BH4. PTPS deficiency (PTPSD) is the major cause of BH4D. In this study, we investigated that the prevalence of BH4D in Jiangxi province was approximately 12.5 per 1,000,000 live births (69/5,541,627). Furthermore, the frequency of BH4D was estimated to be 28.8% (69/240) in the HPA population of Jiangxi. In this study, we aimed to characterize the mutational spectrum of the PTS gene in patients with PTPSD from Jiangxi province.Method: Newborn screening data of Jiangxi province from 1997 to 2021 were analyzed and 53 families with PTPSD were enrolled for the analysis of the PTS gene variants by Sanger sequencing.Results: 106 variants were identified in 106 alleles of 53 patients with PTPSD, including 13 types of variants reported previously, and two novel variants (c.164-36A>G and c.146_147insTG). The predominant variant was c.259C>T (47.2%), followed by c.84-291A>G (19.8%), c.155A>G (8.5%), c.286G>A (6.6%) and c.379C>T (4.7%).Conclusion: The results of this study can not only provide guidance for the molecular diagnosis and genetic counseling in cases of PTPS deficiency but also enrich the PTS mutation database.

Dietary and symbiotic bacteria can exert powerful influence on metazoan lipid metabolism. Recent studies have emerged that microbiota have a role in animal obesity and related health disorders, but the mechanisms by which bacteria influence lipid storage in their host are unknown. To reduce the complexity of the relationship between gut microbiota and the host, Caenorhabditis elegans (C. elegans) has been chosen as a model organism to study interspecies interaction. Here, we demonstrate that feeding C. elegans with an opportunistic pathogenic bacterium Stenotrophomonas maltophilia (S. maltophilia) retards growth and promotes excessive neutral lipid storage. Gene expression analysis reveals that dietary S. maltophilia induces a lipogenic transcriptional response that includes the SREBP ortholog SBP-1, and fatty acid desaturases FAT-6 and FAT-7. Live imaging and ultrastructural analysis suggest that excess neutral lipid is stored in greatly expanded lipid droplets (LDs), as a result of enhanced endoplasmic reticulum (ER)-LD interaction. We also report that loss of function mutations in dpy-9 in C. elegans confers resistance to S. maltophilia. Dietary S. maltophilia induces supersized LDs by enhancing lipogenesis and ER-LD contacts in C. elegans. This work delineates a new model for understanding microbial regulation of metazoan physiology.

Circular RNA (circRNA) is a unique type of endogenous RNA. It does not have free 3 ′or 5′ ends, but forms covalently closed continuous rings. Rheumatoid arthritis (RA) is a common chronic autoimmune joint disease, characterized by chronic inflammation of the joint synovial membrane, joint destruction, and the formation of pannus. Although the pathogenesis of rheumatoid arthritis remains incompletely understood, a growing amount of research shows that circRNA has a close relationship with RA. Researchers have found that abnormally expressed circRNAs may be associated with the occurrence and development of RA. This article reviews the inflammatory immune, functions, mechanisms, and values of the circRNAs in RA to provide new ideas and novel biomarkers for the diagnosis and treatment of RA.

Background and PurposeInfantile neuroaxonal dystrophy (INAD) is a subtype of PLA2G6-Associated Neurodegeneration (PLAN) with an age of early onset and severe clinical phenotypes of neurodegeneration. Individuals affected with INAD are characterized by rapid progressive psychomotor deterioration, neuroregression, and hypotonia followed by generalized spasticity, optic atrophy, and dementia. In this case, we aimed to identify the underlying causative genetic factors of a Chinese family with two siblings who presented with walking difficulty and inability to speak. We provided a prenatal diagnosis for the family and information for the prevention of this genetic disease.MethodsRetrospective clinical information and magnetic resonance imaging (MRI) findings of the proband were collected. Trio-whole exome sequencing (WES) including the proband and his parents was performed to explore the genetic causes, while Sanger sequencing was subsequently used to validate the variants identified by Trio-WES in the pedigree. Furthermore, prenatal molecular genetic diagnosis was carried out through amniocentesis to investigate the status of pathogenic mutations in the fetus by Sanger sequencing at an appropriate gestational age.ResultsThe two siblings were both clinically diagnosed with rapid regression in psychomotor development milestones. Brain MRI showed cerebellar atrophy and typical bilaterally symmetrical T2/FLAIR hyperintense signal changes in periventricular areas, indicating periventricular leukomalacia, and myelin sheath dysplasia. Trio-WES revealed two heterozygous variants in PlA2G6 associated with clinical manifestations in the proband: a novel maternally inherited variant c.217C>T (p.Gln73*) and a previously reported paternally inherited recurrent pathogenic variant c.1894C>T (p.Arg632Trp). These two heterozygous mutations were also detected in the younger brother who had similar clinical features as the proband. The novel variant c.217C>T was classified as “pathogenic (PVS1 + PM2 + PP3),” while the variant c.1894C>T was “pathogenic” (PS1 + PM1 + PM2 + PM3 + PP3) based on the latest American College of Medical Genetics and Genomics (ACMG) guidelines on sequence variants. Combining the molecular evidence and clinical phenotypes, the diagnosis of INAD was established for the two affected siblings. The two variants that were identified were considered the causative mutations for INAD in this family. Prenatal diagnosis suggested compound heterozygous mutations of c.217C>T and c.1894C>T in the fetus, indicating a high risk of INAD, and the parents chose to terminate the pregnancy.ConclusionWe identified a novel pathogenic mutation that broadens the mutation spectrum of PLA2G6 and will provide clues for the molecular diagnosis of INAD. Furthermore, our study has helped to elucidate the causative genetic factors of this Chinese family with INAD effectively and efficiently by using the emerging Trio-WES strategy and providing precise genetic counseling for this family.

Abstract Irrigation is the dominant section of human water use, exerting essential impacts on hydrological processes and water resources. To more realistically simulate irrigation processes in water‐rich regions, an irrigation scheme is incorporated into a land surface‐hydrological model. It calculates the irrigation water requirement according to meteorological conditions, cropping area and growing stage, and root‐zone soil moisture, and determines the irrigation water withdrawal based on the available water resources as well as describing water extraction and irrigation processes in the model. The coupled model is applied to the Yangtze River Basin (YRB) in China, and verified using the observed daily river discharge from 1987 to 1990, evapotranspiration and irrigation amounts from 1999 to 2003. The results first show that the model can well reproduce hydrological processes within the basin, and the simulated irrigation largely agrees with the observation, in terms of annual irrigation and its spatial pattern. Second, inclusion of irrigation processes allows the model to better estimate evapotranspiration, with relative biases decreased from about −10% to −3%. It is also found that in comparison to arid/semi‐arid areas, although presenting a less effect on river discharge and groundwater, the irrigation in the YRB significantly alters hydrological processes through water redistribution. The irrigation‐induced evapotranspiration increment and runoff decrease indicate a shift in the surface water and energy balance, implying a potential effect on the atmosphere. Therefore, representing irrigation processes properly is important, particularly for understanding the coupling effect of the nature‐human system and improving the hydrological prediction accuracy.

Study region: Qingjiang cascade reservoir, China. Study focus: Reservoirs regulate the natural streamflow to utilize water resources comprehensively. How to mine the existing massive reservoir operation data to describe human operation behaviors is a challenge. To address this issue, a data-driven method, Long short-term memory (LSTM), was used to simulate the reservoir outflow by inputting historical information. The physics-guided LSTM model, shortly named PG-LSTM, was formulated by using synthetic flood samples and physical constraints of water balance, boundary, and monotonicity. New hydrological insights: (1) PG-LSTM can reproduce historical outflow with seasonal variations, or predict outflow without lags, (2) knowledge of reservoir operations can guide LSTM with the reduction of negative flow occurrence and the accurate identification of operation behaviors under extreme hydrological conditions, (3) specifically, compared with conventional LSTM, gradient boosting regression tree and conventional reservoir operation, PG-LSTM can improve the Nash-Sutcliffe efficiency of cascade reservoir during the test period from 0.50, 0.20, and 0.17 to 0.54 in the reproduction scenario, and from 0.84, 0.26, and 0.17 to 0.85 in the prediction scenario with five-fold cross-validation method. The PG-LSTM is helpful to describe human operation behaviors of reservoirs.

In this study, a unique 0-D/2-D Ti3C2 structure was assembled by salt-etching Ti3C2 nanodots out of their parent 2-D Ti3C2 nanosheets. The strong quantum confinement in finite-sized nanodots and concomitant nanodents endowed this structure with a gradient bandgap. UV–Vis diffuse reflectance spectrum revealed the bandgap energies of the coated nanodots and inner nanosheets were 2.82 and 2.40 eV, respectively. Accordingly, the 0-D/2-D Ti3C2 was fairly sensitive to sunlight and could efficiently degrade MB, MeB and RhB dyes in contaminated water under solar illumination. Photocatalytic experiments evidenced that less dye adsorption would induce higher removal ratio of the dye. Moreover, cyclic removal experiments showed the photodegradation efficiency of 0-D/2-D Ti3C2 could still exceed 60% after the fifth cycle for MB, MeB and RhB dyes.

To further ascertain the origin of the Ordovician Majiagou Formation reservoirs in the Ordos Basin, the M54-M51 sub-members of the Ordovician Majiagou Formation in the eastern Sulige gasfield of Ordos Basin were taken as examples to analyze the vertical development characteristics of eogenetic karst and to discover the dissolution mechanism and its control on reservoirs through observation of a large number of cores and thin sections. According to detailed analysis of petrologic characteristics, the reservoir rock types include micritic dolomite, grain dolomite and microbialite which have mainly moldic pore, intergranular (dissolved) pore, and (dissolved) residual framework pore as main reservoir space respectively. The study area developed upward-shallowing sequences, with an exposure surface at the top of a single upward-shallowing sequence. The karst systems under the exposure surface had typical exposure characteristics of early dissolution and filling, indicating these reservoirs were related to the facies-controlled eogenetic karstification. With the increase of karstification intensity, the reservoirs became worse in physical properties.

With advances in artificial intelligence, machine learning-based models such as long short-term memory (LSTM) models have shown much promise in forecasting long-term runoff by mapping pathways between large-scale climate patterns and catchment runoff responses without considering physical processes. The recognition of key factors plays a vital role and thus affects the performance of the model. However, there is no conclusion on which recognition algorithm is the most suitable. To address this issue, an LSTM model combined with two attention mechanisms both in the input and hidden layers, namely AT-LSTM, is proposed for long-term runoff forecasting at Yichang and Pingshan stations in China. The added attention mechanisms automatically assign weights to 130 climate phenomenon indexes, avoiding the use of subjectively set recognition algorithms. Results show that the AT-LSTM model outperforms the Pearson’s correlation based LSTM model in terms of four evaluation metrics for monthly runoff forecasting. Further, the set indirect runoff prediction method verifies that the AT-LSTM model also performs effectively in precipitation and potential evapotranspiration forecasting, and the indirect runoff prediction is inferior to the AT-LSTM model to establish a direct link between climate factors and runoff. Finally, four key factors related to runoff are identified by the attention mechanism and their impacts on runoff are analyzed on intra- and inter-annual scales. The proposed AT-LSTM model can effectively improve the accuracy of long-term forecasting and identify the dynamic influence of input factors.

Medium-low-speed maglevs are increasingly used in the urban rail transit industry because of their advantages, such as low noise and low energy consumption. In this study, a finite element analysis of the responses of the subgrade that supports a medium-low-speed maglev structure under a dynamic maglev load is presented. First, the finite element analysis considers a low-lying structure with different elastic moduli. Then, the attenuation laws of the dynamic stress and dynamic deformation for different depth ranges of the subgrade under the rail beam are analyzed. In addition, the magnitude of the influence of the dynamic load is clarified. The results lead to a recommendation of a base bed thickness of 1.5 m, graded gravel or group A filler as the surface layer of filler, and gravel soil as the bottom layer. This study provides theoretical support for the construction design of a subgrade structure under the rail beam of a low-lying maglev line.

Abstract Background TAB2 is an activator of MAP 3 K7/TAK1, which is required for the IL-1 induced signal pathway. Microdeletions encompassing TAB2 have been detected in various patients with congenital heart defects (CHD), indicating that haploinsufficiency of TAB2 causes CHD. To date, seven variants within TAB2 were reported associated with CHD, only two of them are nonsense mutations. Case presentation Here we describe a three-generation Chinese family that included five CHD patients with heart valvular defects, such as mitral or tricuspid valves prolapse or regurgitation, and aortic valve stenosis or regurgitation. Our proband was a pregnant woman presenting with mitral, tricuspid, and aortic defects; her first child experienced sudden cardiac death at the age of 2 years. Whole-exome sequencing of the proband revealed a novel nonsense variant in TAB2 (c.C446G, p.S149X), which results in the elimination of the majority of C-terminal amino acids of TAB2, including the critical TAK1-binding domain. The variant was identified in five affected patients but not in the eight unaffected family members using Sanger sequencing and was classified as “pathogenic” according to the latest recommendation on sequence variants laid out by the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. Conclusion We described a family with CHD caused by a novel TAB2 nonsense mutation. Our study broadens the mutation spectrum of TAB2; to the best of our knowledge, this is the first report of a pathogenic mutation within TAB2 in a Chinese population.

Abstract The increasing penetration of renewable energy sources (RESs) brings more power generation fluctuations into power systems, which puts forward higher requirement on the regulation capacities for maintaining the power balance between supply and demand. In addition to traditional generators for providing regulation capacities, the progressed information and communication technologies enable an alternative method by controlling flexible loads, especially thermostatically controlled loads (TCLs) for regulation services. This paper investigates the modeling and control strategies of aggregated TCLs as the virtual energy storage system (VESS) for demand response. First, TCLs are modeled as VESSs and compared with the traditional energy storage system (ESS) to analyze their characteristic differences. Then, the control strategies of VESS are investigated in microgrid and main grid aspects, respectively. It shows that VESS control strategies can play important roles in frequency regulation and voltage regulation for power systems’ stability. Finally, future research directions of VESS are prospected, including the schedulable potential evaluation, modeling of TCLs, hierarchical control strategies of VESS considering ESSs and RESs and reliability and fast response in frequency control for VESS.

Abstract We have demonstrated the realization of a coherent vesicle random lasing (VRL) from the dye doped azobenzene polymer vesicles self-assembled in the tetrahydrofuran-water system, which contains a double-walled structure: a hydrophilic and hydrophobic part. The effect of the dye and azobenzene polymer concentration on the threshold of random laser has been researched. The threshold of random laser decreases with an increase in the concentration of the pyrromethene 597 (PM597) laser and azobenzene polymer. Moreover, the scattering of small size group vesicles is attributed to providing a loop to boost the coherent random laser through the Fourier transform analysis. Due to the vesicles having the similar structure with the cell, the generation of coherent random lasers from vesicles expand random lasers to the biomedicine filed.

Study region: Upper Yangtze River Basin, China. Study focus: The intensification of climate change and human activities leads to non-stationarity of hydrological processes. Previous studies mainly focus on monthly hydrological or Budyko models. However, it is a challenge that catchment hydrological responses to human activities for daily hydrological models. This study aims to evaluate anthropogenic impacts on water yield of the upper Yangtze River Basin by representing the Xinanjiang model parameters as functions of socio-economic factors. New hydrological insights: The hydrological parameters WM (soil water storage capacity) and KE (ratio of potential evaporation to pan evaporation) increased in 1976–2000, while the parameter B (non-homogeneity of the soil water storage capacity) declined. It is further demonstrated that the population and the drainage area of reservoirs have the greatest impact on B and WM, respectively. Their linear functional form is validated to be effective for improving streamflow simulation. These findings can help understand the non-stationarity of the rainfall-runoff relationship due to increasing human development and contribute to adaptive development strategies for future water resource management.

Abstract When many cities need quantitative forecasts of air quality to adjust industrial production plans and urbanization development, how to build an efficient forecast model remain a challenge. Methodology for quantitative prediction of air quality can no longer rely on single‐site observations, and thus approaches that require fewer input data and are more efficient and more reliable need to be explored. This paper proposes the principles and steps of a new model using the empirical orthogonal function (EOF) and principal component regression (PCR), which is a hybrid EOF‐PCR approach that decomposes the panel data of PM2.5 and predictors into spatial structures (EOFs) and time expansion coefficients (ECs) by EOF analysis, establishes the PCR of the ECs of PM2.5, and simulates the PM2.5 concentrations in each city by projecting the fitted ECs through EOFs. The very heart of the new model is the PCR modeling and projection. The results are presented for PM2.5 concentrations over Jiangsu Province in eastern China. The results show that this EOF‐PCR model, which is based on EC1s with a cumulative variance contribution rate above 90%, has an average prediction accuracy of 65%. The model performs best in spring and autumn, better in summer and worst in winter. Most predictors have a maximum lag of a week, and they are quite different among seasons. Considering the influence of the spatial distributions of predictors, rather than covariates at a single site, this model can reflect regional influences and effectively improve the simulation effect.

Traditional analytical methods for thalassemia screening are needed to process complicated and time-consuming sample pretreatment. In recent decades, ambient mass spectrometry (MS) approaches have been proven to be an effective analytical strategy for direct sample analysis. In this work, we applied ambient MS with wooden-tip electrospray ionization (WT-ESI) for the direct analysis of raw human blood samples that were pre-identified by gene detection. A total of 319 whole blood samples were investigated in this work, including 100 α-thalassemia carriers, 67 β-thalassemia carriers, and 152 control healthy samples. Only one microliter of raw blood sample was directly loaded onto the surface of the wooden tip, and then five microliters of organic solvent and a high voltage of +3.0 kV were applied onto the wooden tip to generate spray ionization. Multiply charged ions of human hemoglobin (Hb) were directly observed by WT-ESI-MS from raw blood samples. The signal ratios of Hb chains were used to characterize two main types of thalassemia (α and β types) and healthy control blood samples. Our results suggested that the ratios of charged ions to Hb chains being at +13 would be an indicator for β-thalassemia screening.

Lipid droplets (LDs) are fat storage organelles that are initiated and expanded by seipins at ER contact sites. Here the authors show that the C. elegans seipin ortholog SEIP-1 is recruited to these sites by certain dietary fatty acids to support the expansion of a subset of LDs.

Very few studies have focused on diatomaceous earth slopes along high-speed railways, and the special properties of diatomaceous earth under alternating dry and wet conditions are unknown. This paper studies diatomaceous earth in the Shengzhou area, through which the newly built Hangzhou–Taizhou high-speed railway passes, and the basic physical and hydraulic properties of diatomaceous earth are analyzed by indoor test methods. A convenient, efficient, and controllable high-speed railway slope artificial rainfall simulation system is designed, and in situ comprehensive monitoring and fissure observation are performed on site to analyze the changes in various diatomaceous soil slope parameters under rainfall infiltration, and to explore the cracking mechanisms of diatomaceous earth under alternating dry and wet conditions. The results indicate extremely poor hydrophysical properties of diatomaceous earth in the Shengzhou area; the disintegration resistance index values of natural diatomaceous earth samples subjected to dry and wet cycles are 1.8–5.6%, and the disintegration is strong. Comprehensive indoor tests and water content monitoring show that natural diatomaceous earth has no obvious influence when it contacts water, but it disintegrates and cracks under alternating dry and wet conditions. The horizontal displacement of both slope types mainly occurs within 0.75–2.75 m of the surface layer, indicating shallow surface sliding; after testing, natural slope crack widths of diatomaceous earth reach 10–25 mm, and their depths reach 40–60 cm. To guarantee safety during high-speed railway engineering construction, implementing proper protection for diatomaceous earth slopes is recommended.

Diabetes mellitus (type 1 and type 2) and its various complications continue to place a huge burden on global medical resources, despite the availability of numerous drugs that successfully lower blood glucose levels. The major challenging issue in diabetes management is the prevention of various complications that remain the leading cause of diabetes-related mortality. Moreover, the limited long-term durability of monotherapy and undesirable side effects of currently used anti-diabetic drugs underlie the urgent need for novel therapeutic approaches. Phytochemicals represent a rich source of plant-derived molecules that are of pivotal importance to the identification of compounds with therapeutic potential. In this review, we aim to discuss recent advances in the identification of a large array of phytochemicals with immense potential in the management of diabetes and its complications. Given that metabolic inflammation has been established as a key pathophysiological event that drives the progression of diabetes, we focus on the protective effects of representative phytochemicals in metabolic inflammation. This paper also discusses the potential of phytochemicals in the development of new drugs that target the inflammation in the management of diabetes and its complications.

Abstract The northeast cold vortex (NECV) is one of the major synoptic systems affecting Northeast China. The activity of NECV is an important reason for severe convective storms. However, research on extreme precipitation over Northeast China and their associations with the northeast cold vortex index (NECVI) is limited. Based on nonstationary generalized extreme value models, we analyze and quantify the contribution of the NECVI and the multiscale synergistic indices. Then, we verify the necessity of the NECVI by the likelihood ratio test and the blank control experiment, and further verify the impact of the NECVI on the extreme precipitation over Northeast China in combination with the climate index atmospheric circulation analysis. Results suggest that the models established with East Asian summer monsoon index, Southern Oscillation Index, and NINO3.4 index as covariates the most common. The NECVI and the synergies also make significant contribution and have passed the likelihood ratio test at 80% confidence. Especially in late summer, accounting for 18.69% of the 10 selected best models and 29.41% of the nine selected best nonstationary models. Based on the blank experiments, the models with the NECVI have a maximum reduction of 4.72% than those without the NECVI in the Akaike information criterion values in late summer. In early summer and late summer, the center of the high values of the water vapor anomaly is mainly located in southwestern in the strong NECVI years. These findings help to understand the genetic mechanism of extreme precipitation over Northeast China and provide reference for risk management.

This study investigates the degradation of nifedipine (NIF) by using a novel and highly efficient ultraviolet light combined with hydrogen peroxide (UV/H2O2). The degradation rate and degradation kinetics of NIF first increased and then remained constant as the H2O2 dose increased, and the quasi-percolation threshold was an H2O2 dose of 0.378 mmol/L. An increase in the initial pH and divalent anions (SO42- and CO32-) resulted in a linear decrease of NIF (the R2 of the initial pH, SO42- and CO32- was 0.6884, 0.9939 and 0.8589, respectively). The effect of monovalent anions was complex; Cl- and NO3- had opposite effects: low Cl- or high NO3- promoted degradation, and high Cl- or low NO3- inhibited the degradation of NIF. The degradation rate and kinetics constant of NIF via UV/H2O2 were 99.94% and 1.45569 min-1, respectively, and the NIF concentration = 5 mg/L, pH = 7, the H2O2 dose = 0.52 mmol/L, T = 20 ℃ and the reaction time = 5 min. The ·OH was the primary key reactive oxygen species (ROS) and ·O2- was the secondary key ROS. There were 11 intermediate products (P345, P329, P329-2, P315, P301, P274, P271, P241, P200, P181 and P158) and 2 degradation pathways (dehydrogenation of NIF → P345 → P274 and dehydration of NIF → P329 → P315).

In this study, a new block-type rail bearing beam is presented, which consists of a cast-in-place base and prefabricated blocks. The finite element analysis is conducted to assess the proposed new rail bearing beam structure. The performed finite element method (FEM) simulation focused on the dynamic stress at the bottom of the rail bearing beam and structural internal force and deformation under the case of train loading, etc. Besides, the relationship between first-order natural frequency and activation frequency in the new support rail beam structure is analyzed and the beneficial effects on the internode connection structure are quantified. The results show that the increase in driving speed has the most significant effect on the vertical acceleration of the structure, and the self-vibration frequency of the structure is relatively large, which means the structure is safe. Since previous research seldom focuses on this block-type rail bearing beam, this study lays a valuable foundation for the construction of a rail bearing beam for the mid-low-speed maglev train.

BackgroundThe purpose was to develop and validate a nomogram for prediction on radiation-induced temporal lobe injury (TLI) in patients with nasopharyngeal carcinoma (NPC).MethodsThe prediction model was developed based on a primary cohort that consisted of 194 patients. The data was gathered from January 2008 to December 2010. Clinical factors associated with TLI and dose–volume histograms for 388 evaluable temporal lobes were analyzed. Multivariable logistic regression analysis was used to develop the predicting model, which was conducted by R software. The performance of the nomogram was assessed with calibration and discrimination. An external validation cohort contained 197 patients from January 2011 to December 2013.ResultsAmong the 391 patients, 77 patients had TLI. Prognostic factors contained in the nomogram were Dmax (the maximum point dose) of temporal lobe, D1cc (the maximum dose delivered to a volume of 1 ml), T stage, and neutrophil-to-lymphocyte ratios (NLRs). The Internal validation showed good discrimination, with a C-index of 0.847 [95%CI 0.800 to 0.893], and good calibration. Application of the nomogram in the external validation cohort still obtained good discrimination (C-index, 0.811 [95% CI, 0.751 to 0.870]) and acceptable calibration.ConclusionsThis study developed and validated a nomogram, which may be conveniently applied for the individualized prediction of TLI.

With the development of the refining industry, the treatment of refinery wastewater has become an urgent problem. In this study, a ceramic membrane (CM) was combined with Fenton-activated carbon (AC) adsorption to dispose of refinery wastewater. The effect of the combined process was analyzed using excitation–emission matrix (EEM), ultraviolet-visible (UV-vis) and Fourier transform infrared spectroscopies (FTIR). Compared with direct filtration, the combined process could significantly improve the removal of organic pollution, where the removal rate of the COD and TOC could be 70% and the turbidity removal rate was above 97%. It was found that the effluent could meet the local standards. In this study, the membrane fouling was analyzed for the impact of the pretreatment on the membrane direction. The results showed that Fenton-AC absorption could effectively alleviate membrane fouling. The optimal critical flux of the combined process was increased from 60 to 82 L/(m2·h) compared with direct filtration. After running for about 20 d, the flux remained at about 55 L/(m2·h) and the membrane-fouling resistance was only 1.2 × 1012 m−1. The Hermia model revealed that cake filtration was present in the early stages of the combined process. These results could be of great use in improving the treatment efficiency and operation cycle of refinery wastewater.

Reservoir operation causes spatiotemporal variations in outflow, which influence the dynamics of downstream aquatic communities. However, empirical evidence of community responses to hydrological alteration remains limited for dam-regulated rivers. This study focused on quantifying the streamflow disturbance to multi-population dynamics in downstream of the China’s Danjiangkou Reservoir. First, the stochastic population dynamics model (PDM) was used to simulate aquatic community dynamics. Then, the flow–ecology relationship was established to identify community response to reservoir outflow. Third, two novel ecological indicators, stable time (ST) and coefficient of variation at stable time (CVST), were proposed to evaluate the resilience and resistance of multi-population systems, respectively. Finally, the reservoir operating rule curves were optimized by considering tradeoffs between socioeconomic and ecological objectives. The coevolution processes of multi-population systems (fish, phytoplankton, zooplankton, zoobenthos, and macrophytes) were simulated by stochastic PDMs. The population densities of stable states showed continuous downward trends with increasing degree of hydrological alteration for multi-population systems, and aquatic community systems could be destroyed when alteration reached its acceptable maximum. The greater the degree of hydrological alteration, the longer the recovery time from an unstable to a stable state, and the weaker resistance for each population system. The resilience and resistance of downstream multi-population systems were enhanced by optimizing reservoir outflow. The optimization results illustrated that the performances of the multiple objectives of water supply, hydropower generation, and ST were improved by 2.37%, 2.40%, and 2.67%, respectively, whereas the performance of CVST was the same as the conventional operation. The flow–ecology relationship provided an approach to quantify the impacts of reservoir outflow on an aquatic community, which is helpful in guiding ecological flow strategies.

Investigation of quantitative predictions of precipitation amounts and forecasts of drought events are conducive to facilitating early drought warnings. However, there has been limited research into or modern statistical analyses of precipitation and drought over Northeast China, one of the most important grain production regions. Therefore, a case study at three meteorological sites which represent three different climate types was explored, and we used time series analysis of monthly precipitation and the grey theory methods for annual precipitation during 1967–2017. Wavelet transformation (WT), autoregressive integrated moving average (ARIMA) and long short-term memory (LSTM) methods were utilized to depict the time series, and a new hybrid model wavelet-ARIMA-LSTM (W-AL) of monthly precipitation time series was developed. In addition, GM (1, 1) and DGM (1, 1) of the China Z-Index (CZI) based on annual precipitation were introduced to forecast drought events, because grey system theory specializes in a small sample and results in poor information. The results revealed that (1) W-AL exhibited higher prediction accuracy in monthly precipitation forecasting than ARIMA and LSTM; (2) CZI values calculated through annual precipitation suggested that more slight drought events occurred in Changchun while moderate drought occurred more frequently in Linjiang and Qian Gorlos; (3) GM (1, 1) performed better than DGM (1, 1) in drought event forecasting.

An asymmetrical dual-core photonic crystal fiber (DC-PCF), which possesses all circular air holes, is proposed. By setting appropriate geometrical parameters, the wavelength-selective coupling property is realized, and a compact optical filter with a short length of 1.83 mm based on the DC-PCF is designed. The spectral transmission characteristics of the filter are investigated by the beam propagation method. The results demonstrate that the optical filter possesses a bandwidth of ~58 nm and small sidelobes. The proposed optical filter could be used in the integrated optical systems.

This paper provides a review of advances in conjugated polymer lasers. High photoluminescence efficiencies and large stimulated emission cross-sections coupled with wavelength tunability and low-cost manufacturing processes make conjugated polymers ideal laser gain materials. In recent years, conjugated polymer lasers have become an attractive research direction in the field of organic lasers and numerous breakthroughs based on conjugated polymer lasers have been made in the last decade. This paper summarizes the recent progress of the subject of laser processes employing conjugated polymers, with a focus on the photoluminescence principle and excitation radiation mechanism of conjugated polymers. Furthermore, the effect of conjugated polymer structures on the laser threshold is discussed. The most common polymer laser materials are also introduced in detail. Apart from photo-pumped conjugated polymer lasers, a direction for the future development of electro-pumped conjugated polymer lasers is proposed.

Subwavelength optical micro/nanofibers have several advantages, such as compact optical wave field and large specific surface area, which make them widely used as basic building blocks in the field of micro-nano optical waveguide and photonic devices. Among them, polymer micro/nanofibers are among the first choices for constructing micro-nano photonic components and miniaturized integrated optical paths, as they have good mechanical properties and tunable photonic properties. At the same time, the structures of polymer chains, aggregated structures, and artificial microstructures all have unique effects on photons. These waveguided micro/nanofibers can be made up of not only luminescent conjugated polymers, but also nonluminous matrix polymers doped with luminescent dyes (organic and inorganic luminescent particles, etc.) due to the outstanding compatibility of polymers. This paper summarizes the recent progress of the light-propagated mechanism, novel design, controllable fabrication, optical modulation, high performance, and wide applications of the polymer micro/nanofiber fluorescence waveguide. The focus is on the methods for simplifying the preparation process and modulating the waveguided photon parameters. In addition, developing new polymer materials for optical transmission and improving transmission efficiency is discussed in detail. It is proposed that the multifunctional heterojunctions based on the arrangement and combination of polymer-waveguided micro/nanofibers would be an important trend toward the construction of more novel and complex photonic devices. It is of great significance to study and optimize the optical waveguide and photonic components of polymer micro/nanofibers for the development of intelligent optical chips and miniaturized integrated optical circuits.

Studies on the following were reviewed: (1) the structure of spiropyrans and spirooxazines (two kinds of spiro compounds) under external stimuli and (2) the construction and applications of composite systems based on fluorescence resonance energy transfer (FRET) with fluorescent materials. When treated with different stimuli (light, acids and bases, solvents, metal ions, temperature, redox potential, and so on), spiropyrans/spirooxazines undergo transformations between the ring-closed form (SP), the ring-opened merocyanine (MC) form, and the protonated ring-opened form (MCH). This is due to the breakage of the spiro C–O bond and the protonation of MC, along with a color change. Various novel, multifunctional materials based on photochromic spiropyrans and spirooxazines have been successfully developed because of the vastly differently physiochemical properties posssed by the SP, MC and MCH forms. Among the three different structural forms, the MC form has been studied most extensively. The MC form not only gives complexes with various inorganic particles, biological molecules, and organic chemicals but also acts as the energy acceptor (of energy from fluorescent molecules) during energy transfer processes that take place under proper conditions. Furthermore, spiropyran and spirooxazine compounds exhibit reversible physicochemical property changes under proper stimuli; this provides more advantages compared with other photochromic compounds. Additionally, the molecular structures of spiropyrans and spirooxazines can be easily modified and extended, so better compounds can be obtained to expand the scope of already known applications. Described in detail are: (1) the structural properties of spiropyrans and spirooxazines and related photochromic mechanisms; (2) composite systems based on spiropyrans and spirooxazines, and (3) fluorescent materials which have potential applications in sensing, probing, and a variety of optical elements.

In order to meet the demands of operation monitoring of large scale, autoscaling, and heterogeneous virtual resources in the existing cloud computing, a new method of live virtual machine (VM) migration detection algorithm based on the cellular neural networks (CNNs), is presented. Through analyzing the detection process, the parameter relationship of CNN is mapped as an optimization problem, in which improved particle swarm optimization algorithm based on bubble sort is used to solve the problem. Experimental results demonstrate that the proposed method can display the VM migration processing intuitively. Compared with the best fit heuristic algorithm, this approach reduces the processing time, and emerging evidence has indicated that this new approach is affordable to parallelism and analog very large scale integration (VLSI) implementation allowing the VM migration detection to be performed better.

We demonstrated negative refraction effects of light propagating in two-dimensional square and hexagonal-lattice silicon photonic crystals (PhCs). The plane wave expansion method was used to solve the complex eigenvalue problems, as well as to find dispersion curves and equal-frequency contour (EFC). The finite-difference time-domain (FDTD) method was used to simulate and visualize electromagnetic wave propagation and scattering in the PhCs. Theoretical analyses and numerical simulations are presented. Two different kinds of negative refractions, namely, all-angle negative refraction (AANR) without a negative index and negative refraction with effective negative index, have been verified and compared.