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Water conservation is an important ecosystem service, which is crucial to the fragile ecological environment and serious soil erosion in Northwest China. However, water conservation has been affected by climate change and human disturbance, and its future spatial and temporal changes are still unclear. This study employed the Integrated Valuation of Ecosystem Services and Trade‐offs (InVEST) model to assess the water conservation capacity of Northwest China between 1990 and 2020. Subsequently, the Patch‐generating Land Use Simulation (PLUS) model and the NASA Earth Exchange Global Daily Downscaled Projections (NEX‐GDDP‐CMIP6) were integrated to examine changes in water conservation from 2030 to 2050. The water conservation quantity in Northwest China had a fluctuating growth tendency between 1990 and 2020, with an average of 816.61 × 108 m3. The water conservation capacity's regional distribution pattern shows a steady increase from northwest to southeast. Northwest China's forest land had the greatest water conservation capacity between 1990 and 2020, at 66 mm, while the water land had the lowest, at 1.46 mm. The water conservation capacity in the 2030–2050 future scenario is less than that in 2020 when the regional distribution pattern is comparable to 2020. Natural development scenario (ND) in 2030 has the lowest water conservation capacity (13.41 mm) under ssp1‐2.6 precipitation scenario, whereas in 2050, the highest water conservation capacity (17.47 mm) is found in same scenario. The ecological protection scenario (EP) has the greatest water retention capacity (18.15 mm in 2040) and the lowest (14.38 mm in 2050) in the ssp5‐8.5 scenario. Our research can help restore and rebuild Northwest China's natural ecosystem and offer a theoretical foundation for the protection of ecological environment and the rational utilization of water resources in the region. [ABSTRACT FROM AUTHOR]

Owing to high water content and homogeneous texture, conventional hydrogels hardly reach satisfactory mechanical performance. Tensile‐resistant groups and structural heterogeneity are employed to fabricate tough hydrogels. However, those techniques significantly increase the complexity and cost of material synthesis, and have only limited applicability. Here, it is shown that ultra‐tough hydrogels can be obtained via a unique hierarchical architecture composed of chemically coupled self‐assembly units. The associative energy dissipation among them may be rationally engineered to yield libraries of tough gels with self‐healing capability. Tunable tensile strength, fracture strain, and toughness of up to 19.6 MPa, 20 000%, and 135.7 MJ cm⁻3 are achieved, all of which exceed the best known records. The results demonstrate a universal strategy to prepare desired ultra‐tough hydrogels in predictable and controllable manners. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the patterns of drought and flood alternation in adjacent months is essential for enabling climate adaptation and mitigation strategies. However, there is a paucity of knowledge regarding short‐cycle drought–flood abrupt alteration (s‐DFAA) and its responses to multiple environmental factors at various timescales. This is because of the inadequate formula construction of the existing short‐cycle drought–flood abrupt alteration index (SDFAI), such as the inability to introduce drought standards. To accurately capture the s‐DFAA's characteristics in the Qinling‐Daba Mountains (Qinba Mountains), we proposed a revised SDFAI (R‐SDFAI), which incorporates the standardized precipitation index (SPI) and allows for the customization of drought standards. Next, we used wavelet transform coherence and multiple wavelet coherence to investigate the timescale relationships between s‐DFAA events and their influence factors such as relative humidity, sunshine duration, temperature, evaporation, Arctic Oscillation (AO), Niño3.4 SSTA Index (Niño3.4), Total Sunspot Number Index (TSNI) and Pacific Decadal Oscillation Index (PDO). Our results showed that the R‐SDFAI outperformed traditional SDFAI in capturing s‐DFAA events and characterizing their severity. Furthermore, s‐DFAA events identified by R‐SDFAI at different levels (i.e., mild, moderate, severe, extreme and total) displayed insignificant downward trends. Spatially, there were more s‐DFAA events in the east than the west. Wavelet analysis indicated that meteorological factors and teleconnections significantly impact s‐DFAA events at large timescales, though their driving mechanisms differed substantially. Among meteorological factors, single relative humidity and its related combinations exhibited relatively high percent area of significant coherence (PASC, ranging from 17.47 to 29.46). Each teleconnection and its combinations are irreplaceable, with PASC values always increasing with the number of variables. The PASC ranges from 8.3 to 10.29 for one factor, 12.38 to 18.65 for two factors, 24.02 to 30.58 for three factors and 40.88 for four factors, respectively. [ABSTRACT FROM AUTHOR]

Introduction: Whether the coronavirus disease‐2019 (COVID‐19) pandemic is associated with a long‐term negative impact on acute stroke care remains uncertain. This study aims to compare the timing of key aspects of stroke codes between patients before and after the COVID‐19 pandemic. Methods: This retrospective cohort study was conducted at an academic hospital in Shanghai, China and included all adult patients with acute ischemic stroke hospitalized via the emergency department (ED) stroke pathway during the 24 months since the COVID‐19 outbreak (COVID‐19: January 1, 2020–December 31, 2021). The comparison cohort included patients with ED stroke pathway visits and hospitalizations during the same period (pre‐COVID‐19: January 1, 2018–December 31, 2019). We compared critical time points of prehospital and intrahospital acute stroke care between patients during the COVID‐19 era and patients during the pre‐COVID‐19 era using t test, χ2, and Mann–Whitney U test where appropriate. Results: A total of 1194 acute ischemic stroke cases were enrolled, including 606 patients in COVID‐19 and 588 patients in pre‐COVID‐19. During the COVID‐19 pandemic, the median onset‐to‐hospital time was about 108 min longer compared with the same period of pre‐COVID‐19 (300 vs 192 min, p = 0.01). Accordingly, the median onset‐to‐needle time was 169 min in COVID‐19 and 113 min in pre‐COVID‐19 (p = 0.0001), and the proportion of patients with onset‐to‐hospital time within 4.5 h was lower (292/606 [48.2%] vs 328/558 [58.8%], p = 0.0003) during the pandemic period. Furthermore, the median door‐to‐inpatient admission and door‐to‐inpatient rehabilitation times increased from 28 to 37 h and from 3 to 4 days (p = 0.014 and 0.0001). Conclusions: During the 24 months of COVID‐19, a prolongation of stroke onset to hospital arrival and to intravenous rt‐PA administration times were noted. Meanwhile, acute stroke patients needed to stay in the ED for a longer time before hospitalization. Educational system support and process optimization should be pursued in order to acquire timely delivery of stroke care during the pandemic. [ABSTRACT FROM AUTHOR]

There are conventionally coherent and incoherent types of random lasers, which are characteristic of broadband and randomly distributed narrow‐band lasing spectrum, respectively. No fixed phase relationship has ever been observed between the lasing modes in such lasers. However, herein a new form of random lasers in patterned organic–inorganic hybrid perovskite MAPbBr3 is discovered, where multiple simultaneously lasing modes are stably locked in phase so that lasing lines are achieved with equal spectral separations. This is the first observation of phase locking between random lasers, which is established by the cascaded molecular absorption‐emission or cascaded excitation‐injection processes between random laser modes. The fixed phase relationship is determined by the ultrafast relaxation of the excited molecules to the lower edge of the excitation band, correlating directly the absorption/excitation and emission/injection processes and producing a fixed phase shift. Thus, the bandwidth and separation of the lasing lines are dependent on the relaxation lifetime of the excited molecules and the number of cascading cycles. Such cascading dynamics has a timescale faster than 300 fs. These characteristics innovate the physics and explore new applications of both the MAPbBr3 material and the random lasers. Such a strong phase‐locking mechanism suggests new mode‐locking schemes for ultrafast lasers. [ABSTRACT FROM AUTHOR]

Soil moisture controls the exchange of energy between the land surface and the atmosphere and significantly affects plant growth and productivity. Hyperspectral (350–2500 nm) monitoring of soil moisture content (SMC) could provide a theoretical basis for the real‐time estimation of spatial and temporal variations in soil moisture. During this study, we have developed SMC prediction models in different soil moisture ranges by using the combination of spectral preprocessing methods and optimized spectral indices. Results indicated that first‐order derivative (FD) preprocessing method can highlight the effective information of the spectra and improve the correlation between spectral reflectance and SMC. The spectral reflectance exhibited a strong correlation with SMC near 1400, 1700, 1900, and 2200 nm. The FD‐NDSI‐W0‐model had the best SMC prediction and applicability (R2 = 0.977, root mean square error = 3.413%, relative percent deviation = 6.171) to predict SMCs. Overall, pretreatment methods, combined with the two‐band random combination to optimize the spectral index to build a prediction model of SMC, could be applied for accurate monitoring of SMC. Core Ideas: The spectral features were enhanced using preprocessing methods.The characteristic bands of soil moisture content are clarified.The spectral indices were optimized using a two‐band random combination. [ABSTRACT FROM AUTHOR]

Microactuators that convert external stimuli such as heat, light, current, and magnetic field into mechanical motion are essential components in microelectro‐mechanical systems. To date, microactuators have been fabricated mainly using conventional microfabrication technologies and inorganic thin films, but although such technologies facilitate the mass production of microdevices, they are expensive and lack flexibility when either preparing only a few devices or facing special needs. Laser‐direct‐writing is an effective complement to microfabrication, but is seldom used in the construction of inorganic microactuators. In this work, a laser‐direct‐writing technique on the freestanding vanadium dioxide (VO2) film for fabricating microactuators with arbitrary shapes is developed. The precision of the laser direct writing attained 2 µm under ultralow pulse energy of 52 pJ. The pulse energy is two orders of magnitude lower than that needed for patterning VO2 film and other semiconductor materials on substrates. The overall performance of the resulting VO2 microactuators is comparable with that of those fabricated by conventional microfabrication technologies, but the fabricating efficiency and flexibility are increased. Such a fabrication strategy can also be used to fabricate other smart microdevices, such as strain sensors and photodetectors. [ABSTRACT FROM AUTHOR]

Dry/wet conditions are one of the key constituents of climate change. The understanding of dry/wet variability is vital for production and water resources management. In this research, the temporal variations of 12‐month timescale standardized precipitation evapotranspiration (SPEI) over 2021–2100 under the SSP1‐2.6, SSP2‐4.5, SSP3‐7.0 and SSP5‐8.5 scenarios in seven subregions and China's mainland were investigated over the baseline period of 1961–2000. The run theory was used to project the variations of dry/wet frequency, duration and severity at different levels during 1961–2000, 2021–2060 and 2061–2100 based on the estimated SPEI. The results showed that dry tendency would occur in northwest China. The linear trend for SSP1‐2.6, SSP2‐4.5, SSP3‐7.0 and SSP5‐8.5 were −0.056, −0.031, 0.009 and −0.072 per decade, respectively. While wet tendency would occur in the other regions over 2021–2100. The mild, moderate and severe dry/wet duration and severity over 2021–2060 and 2061–2100 would gradually decrease. Except for northwest China and Qinghai‐Tibetan Plateau, the extreme drought duration and severity would increase in the other subregions, while the extreme wet duration and severity would increase in most regions of China. The drought frequency in north China would range from 0 to 14 times and be smaller than the other regions over 2021–2060 and 2060–2100. However, the wet frequency in south China would be larger than that in the other regions. The dry/wet frequency duration and severity for the SSP5‐8.5 scenario would be the largest among the four scenarios. The projected dry/wet conditions can provide useful information for future water resources management. [ABSTRACT FROM AUTHOR]

Summary: Rice starch was hydrophobised by octenyl succinic anhydride (OSA) and then modified by roast dry heating at 180°C for 40 min (RDH‐40) to improve its digestibility. The oil‐in‐water Pickering emulsions stabilised by double‐modified starch particles were fabricated. The emulsion stability under different formulation parameters was investigated. Results showed that the suitable parameters for fabrication of Pickering emulsion were RDH‐40 concentration of 4.0 wt.%, oil volume ratio of 50% and pH of the system was 7.0. The addition of NaCl and sucrose (0–200 mmol/L) slightly reduced the emulsion stability. Microstructure results revealed that the starch particles and a few gelatinized starch macromolecules distributed around the oil droplets, making the emulsion more stable. Compared with the emulsions stabilised by Tween 20 and OSA starch, the Pickering emulsion stabilised by 4.0% RDH‐40 starch showed the highest loading and embedding rates for curcumin at 25 and 40°C. The emulsion stabilised by RDH‐40 had a faster free fatty acid release rate and higher curcumin bioaccessibility than that stabilised by OSA starch during in vitro digestion. This study helps to develop new starch‐based Pickering emulsions for the delivery of oil‐soluble bioactive substances. [ABSTRACT FROM AUTHOR]

BACKGROUND: As a potential selenium‐enriched crop, it is of great significance to study the selenium application of Tartary buckwheat. Therefore, to study the effects of selenium application concentration, variety, selenium application period and method on the grain selenium content and yield of Tartary buckwheat, an orthogonal experimental design was used to carry out field experiments in the Jinzhong and Northwest Shanxi ecological regions at the same time. Heifeng 1 and Jinqiao 2 were applied at the branching stage and flowering stage in the Jinzhong, and Heifeng 1 and Jinqiao 6 were applied at the early flowering stage and peak flowering stage in the Northwest Shanxi with different concentrations of sodium selenite (0, 1.37, 2.74, 5.48, 8.22, 12.33, 18.495, 27.7425 g hm−2) by foliar spraying and soil application. RESULTS: The results showed that the selenium content in Tartary buckwheat grains was positively correlated with the selenium application concentration and increased with increasing selenium application concentration, while the yield of Tartary buckwheat first increased and then decreased with the selenium application concentration. The grain selenium content and yield of Tartary buckwheat were affected by the selenium application concentration, variety and application method. CONCLUSION: The most effective selenium biofortification program was spraying 2.32 g hm−2 sodium selenite on the leaves of Heifeng 1 at the early flowering stage in the Jinzhong. In the Northwest Shanxi, spraying 11.01 g hm−2 sodium selenite on the leaves of Jinqiao 6 at the flowering stage was the most effective selenium biofortification program. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: Soil carbon sequestration is of great significance to achieve carbon neutralization at an early date. Aims: The present study was conducted in order to explore the interactive effects of conservation tillage on soil organic carbon (SOC) and aggregate stability, and to understand the response of soil organic carbon to aggregate structure and distribution characteristics. Methods: Undisturbed soil from varying depths was collected from the conservation tillage demonstration base under differential tillage practices (NT, no‐tillage mulch; DT, deep‐tillage mulch; CT, conventional‐tillage mulch). SOC and stable‐aggregates of different particle sizes, their number, and structures were analyzed and the relationship between the stability of soil aggregates and SOC was presented. Results: The SOC content was the highest under CT treatment (1.67 g kg–1) and the lowest under NT treatment (1.31 g kg–1). In surface soil, the number of macroaggregates (>0.25 mm, M) under NT treatment was the largest (89.1%), the mean weight diameter (MWD) and geometric mean diameter (GMD) of water stability and mechanical aggregates were the highest, and the fractal dimension (D) was the lowest. This indicated that the NT treatment could maintain the aggregate structure of surface soil well. In the short term, DT and CT could increase SOC content, while NT could decrease SOC content. There was a significant correlation between SOC content and MWD (R2 = 0.40), GMD (R2 = 0.38), and D (R2 = 0.44). The more stable the aggregate structure, the higher the soil fixation and maintenance of SOC. Conclusions: SOC content and aggregate stability have a synergistic effect, and NT can promote the formation of soil aggregates, improve their stability, and balance the distribution of carbon in soil aggregates with different particle sizes. [ABSTRACT FROM AUTHOR]

Objectives: To explore the relationship between cardiac function and pulmonary flow characteristics in tricuspid valve malformation (TVM) fetuses by conventional and speckle tracking echocardiography. Methods: Eighty‐eight TVM fetuses were retrospectively included and compared with 80 normal controls. TVM fetuses in each trimester were divided into two subgroups according to pulmonary flow characteristics: those with normal pulmonary flow (TVM‐N) and those with reduced or absent pulmonary flow (TVM‐R/A). Cardiac measurements, Celermajer index, and Simpson‐Andrews‐Sharland (SAS) score were obtained. Speckle tracking echocardiography was used to compute ventricular deformation parameters. Results: TVM fetuses demonstrated significantly lower global longitudinal strain (GLS) and strain rate for both ventricles than controls (all P <.05). When compared with TVM‐N, left ventricular (LV) ejection fraction, LV fractional area change, right ventricular (RV) fractional area change, LVGLS, and RVGLS were significantly reduced (all P <.05), while the RV diameter Z‐score, RV/LV diameter, SAS score, and Celermajer index were obviously increased in TVM‐R/A in both trimesters (all P <.05). Both LVGLS and RVGLS correlated with cardiothoracic circumference ratio, RV diameter Z‐score, RV/LV diameter, Celermajer index, and SAS score (all P <.01). There was a slow decline for LVGLS and RVGLS in TVM‐N fetuses throughout the gestation. Conversely, these two parameters worsened rapidly in TVM‐R/A group. Conclusions: TVM fetuses present biventricular dysfunction by deformation analysis in the second and third trimester of pregnancy. TVM fetuses with reduced or absent pulmonary flow exhibit significantly greater impairment and more rapid deterioration of cardiac function, which may contribute to poor outcomes. Access the CME test here and search by article title. [ABSTRACT FROM AUTHOR]

Objective: We investigated a custom congenital heart disease (CHD) geneset to assess the diagnostic value of whole‐exome sequencing (WES) in karyotype‐ and copy number variation (CNV)‐negative aborted fetuses with conotruncal defects (CTDs), and to explore the impact of postnatal phenotyping on genetic diagnosis. Methods: We sequentially analyzed CNV‐seq and WES data from 47 CTD fetuses detected by prenatal ultrasonography. Fetuses with either a confirmed aneuploidy or pathogenic CNV were excluded from the WES analyses, which were performed following the American College of Medical Genetics and Genomics recommendations and a custom CHD‐geneset. Imaging and autopsy were applied to obtain postnatal phenotypic information about aborted fetuses. Results: CNV‐seq identified aneuploidy in 7/47 cases while 13/47 fetuses were CNV‐positive. Eighty‐five rare deleterious variants in 61 genes (from custom geneset) were identified by WES in the remaining 27 fetuses. Of these, five pathogenic or likely pathogenic variants (PV/LPV) were identified in five fetuses, revealing a 10.6% (5/47) incremental diagnostic yield. Furthermore, RERE:c.2461_2472delGGGATGTGGCGA was reclassified as LPV based on postnatal phenotypic data. Conclusion: We have developed and defined a CHD gene panel that can be utilized in a subset of fetuses with CTDs. We demonstrate the utility of incorporating both prenatal and postnatal phenotypic information may facilitate WES diagnostics. Key points: What's already known about this topic? To date, whole‐exome sequencing has been widely used for genetic diagnosis of congenital heart disease, and a large number of variants responsible for congenital heart disease have been identified. Few studies have focused on the genetic diagnosis of fetuses aborted due to severe congenital heart disease. What does this study add? We customized a panel of congenital heart disease causative genes based on previous studies and used it to analyze whole exome data in fetuses with cardiac conotruncal malformations following pregnancy termination.The present study evaluates the diagnostic yield of a custom gene panel and also further highlights the additional diagnostic value of postnatal phenotypic analysis derived from postmortem evaluation. [ABSTRACT FROM AUTHOR]

Optical feedback for either the excitation or the signal is an effective approach to enhance the detection sensitivity of Raman scattering spectroscopy. A combination of plasmonic and optical feedback schemes may supply multifold enhancement mechanisms with further improved efficiency. Herein, a plasmonic Bragg grating (PBG) consisting of periodically distributed silver nanoslabs coated onto the sidewalls of the grating lines is reported. Localized surface plasmons excited in the silver nanoslabs with a large width/thickness ratio facilitate enhanced local field and Raman interaction. Asymmetric Bragg diffraction not only supplies optical feedback along the grating plane to extend largely the laser–molecule interaction distance but also enables efficient collection of the Raman signal through back‐diffraction into the detection system. Such a design accomplishes "volume" surface‐enhanced Raman scattering with a modulation depth of more than 500 nm and strong optical feedback, extending largely the limited interaction distance of surface plasmons. With respect to the scheme using Ag films for enhancement, a further enhancement factor larger than 2.8 × 103 has been achieved by the PBG device in the direct detection of the low‐concentration water solution of R6G molecules. The discovered photophysics is potentially important for practical applications in in situ water pollutant detection. [ABSTRACT FROM AUTHOR]

Probiotics are expected to be an ideal alternative for antibiotics in the poultry industry. This study aimed to investigate the effect of Lactobacillus plantarum on growth traits, slaughter performance, serum markers and intestinal bacterial community of Daheng broilers. A total of 2400 healthy one‐day‐old Daheng broilers were randomly divided into 5 groups with 6 replicates per group and 40 individuals per replicate. Birds in control group were fed a basal diet, and others were fed basal diets supplemented with 105, 106, 107 and 108 CFU/kg Lactobacillus plantarum, respectively. It turned out that adding Lactobacillus plantarum to diet could significantly improve the serum immune performance of broilers (p < 0.05), enhance the antioxidant capacity to a certain extent (p > 0.05), but had no significant effect on growth traits and slaughter performance. Moreover, Lactobacillus plantarum could improve the diversity of intestinal bacterial community, but with the increase of addition concentration, the diversity would gradually decrease. In conclusion, Lactobacillus plantarum can be used as feed additive in broiler production, but whether it is more effective than antibiotics needs further investigation. [ABSTRACT FROM AUTHOR]

The effects of non‐thermal plasma (NTP) on the physicochemical properties of wheat flour and the quality of fresh wet noodles (FWN) were investigated. The results showed that NTP effectively decreased the total plate count (TPC), yeast and mould count (YMC) and Bacillus spp. in wheat flour. Wet gluten contents and the stability time reached the maximum when treated for 20 s. The viscosity of starch increased significantly after treatment due to the increased of damaged starch. The contents of secondary structure were altered to some extent, which was because that the ordered network structure of gluten protein broken. Furthermore, compared with the control, texture properties of FWN were enhanced significantly at 20 s, and the darkening rate of FWN was greatly inhibited due to the low polyphenol oxidase (PPO) activity. Consequently, the most suitable treatment was 500 W for 20 s, providing a basis for the application of NTP in flour products. [ABSTRACT FROM AUTHOR]

The effects of electric dry heat (EDH) and roast dry heat (RDH) on characteristics of octenyl succinic anhydride modified rice starches are investigated. The oil‐in‐water Pickering emulsions are prepared using EDH and RDH starch particles as stabilizers, the stability and interfacial structure of emulsions are evaluated. The results from scanning electron microscopy and Fourier transform infrared spectroscopy demonstrate that rice starches remain in granule structure, and no new absorption peaks are detected after heat treatments. The results of differential scanning calorimeter revealed that gelatinization temperatures (TO, TP,TC), and enthalpy (ΔHgel) have significant reductions after heat treatment (p < 0.05). The starches remain an A‐type crystallite with increased in vitro digestibility, however the relative crystallinity decreases from 26.73% to 21.74%. The emulsions stabilized by starches of RDH treatments at 180 °C for 40 and 60 min have the maximum cream volumes, while the emulsions stabilized by EDH starches have no obvious effects. Confocal laser scanning microscopy indicates that the multiple‐modified starch particles adsorb at the oil–water interface and present a mechanical barrier to prevent droplets from merging, thus increasing the emulsion stability. The dry heat treatments coupling with hydrophobic modification may be a promising technique to produce starch‐based Pickering stabilizers. [ABSTRACT FROM AUTHOR]

In this study, a polyimide/aminopropyllsobutyl polyhedral oligomeric silsesquioxane (PI/A‐POSS) membrane with a novel 3D thermal crosslinking structure is prepared by electrospinning and subsequent imidization. Compared with the pure PI membrane, PI/A‐POSS composite membranes present better mechanical properties, narrower distribution of pore size, smaller average pore size, and better thermal stability. When A‐POSS content is 3 wt%, the composite membrane (A3) has outstanding electrolyte uptake, excellent ionic conductivity, low interfacial resistance, and the high electrochemical stability of anode. The battery assembled with the A3 separator has an excellent first discharge capacity of 137.8 mAh g−1 and its capacity retention rate is still as high as 76.49% after 100 cycles at 2.0 C. Furthermore, battery assembled with the A3 separator shows excellent rate capacity with a relatively high discharge capacity up to 169.7 mAh g−1 at 0.2 C and a superior capacity recovery rate of 98.06% at 30 °C. Especially, the battery assembled with the A3 separator shows more prominent rate capacity with an excellent first discharge capacity up to 180.5 mAh g−1 at 0.2 C and a superior capacity recovery rate of 95.79% at 60 °C. [ABSTRACT FROM AUTHOR]

Visible and near‐infrared reflectance (Vis‐NIR) spectroscopy is considered a promising tool for the estimation of soil properties. Soil clay content and soil organic matter (SOM) are main components affecting soil spectra. Accurate assessment of clay content and SOM is essential before achieving accurate prediction for other soil properties. Selecting the proper spectral transformation technique and optimal calibration method are important processes to improve model performance. In this study, a total of 240 soil samples were collected from the main area of winter wheat (Triticum aestivum L.) fields in the Southwest region of Shanxi province, northern China. Six spectral pre‐treatments and three multivariate methods were utilized to realize the estimation of clay content and SOM. Finally, the important spectral wavelengths were identified as 440, 762, 1,150, 1,410, 1,460, 1,860, 1,900, 2,250, 2,400 nm for clay content and 410, 450, 550, 625, 780, 850, 1,410, 1,670, 1,730, 1,860, 1,910, 1,960, 2,250 nm for SOM. Specifically, the wavelengths around 440 (450), 1,900 (1,910) nm and wavebands of 1,410, 1,860, and 2,250 nm were highly related to both clay content and SOM. The optimal prediction was obtained when multiple linear regression (MLR) was combined with standard normal variate (SNV) pre‐processing (R2 =.714, RMSE = 3.982, RPD = 1.584) for clay content and multiplicative scatter correction (MSC) pre‐processing (R2 =.856, RMSE = 2.994, RPD = 2.443) for SOM. This study implied that spectral transformation had an evident effect on spectral curves shape, correlation, and model performance. The choice of pre‐processing transformation should depend on the multivariate technique which has a determined ability to improve the model accuracy. Core Ideas: Determining the important spectral wavelengths for soil clay and soil organic matter.Realizing the robust estimation on soil clay and soil organic matter by using spectral technology.Exploring the approaches to improve predictive accuracy of soil clay and soil organic matter models. [ABSTRACT FROM AUTHOR]

Two novel 2′‐hydroxychalcone derivatives (i.e., M1 and M2) are explored in this work. We mainly focus on investigating the effects of photoexcitation on hydrogen bonds and on the excited‐state intramolecular proton transfer (ESIPT) process. On the basis of calculations of electrostatic potential surface and intramolecular interactions, we verify the formation of hydrogen bond O1H2···O3 in both S0 and S1 states. Exploring the ultraviolet–visible spectra in the liquid phase, our simulated results reappear in the experimental phenomenon. Analyzing molecular geometry and infrared stretching vibrational spectra, we confirm O1H2···O3 is strengthened for both M1 and M2 in the S1 state. We further confirm that charge redistribution facilitates ESIPT tendency. Constructing potential energy curves, we find the ultrafast ESIPT behavior for M1, which is because of the deficiency of side hydroxyl moiety comparing with M2. This work makes a reasonable affiliation of the ESIPT mechanism for M1 and M2. We wish this paper could facilitate understanding these two novel systems and promote their applications. [ABSTRACT FROM AUTHOR]

Summary: Starch botanical origin is a key factor for the characteristics of Pickering emulsion. Starches with different sizes from rice (2.9–7.6 µm), waxy corn (9.3–25.0 µm), wheat (11.4–33.7 µm) and potato (24.4–54.1 µm) were esterified by octenyl succinic anhydride. The modified starch particles were used as stabilisers to produce oil‐in‐water Pickering emulsions. The physical stability, microstructures and rheological properties of different emulsions were compared. Results indicated that the emulsion stabilised with rice starch particles had the minimum droplet size of 83.6 µm and best physical stability during 30 days of storage. Moreover, starch particle size was negatively correlated with emulsion stability (P < 0.05). The particles (3.85% of the emulsion, w/w) built up wall‐like structures around oil droplets, which prevented them from freely moving. All emulsions showed pseudoplastic fluid behaviours and presented gel properties, but elastic modulus (G′) and loss modulus (G″) were mainly affected by starch botanical origins. [ABSTRACT FROM AUTHOR]

Sichuan mountainous black‐bone (SMB) chicken is a small‐sized black‐feathered chicken breed with low amount of meat, while Dahen (DH) chicken has a larger body size and a faster growth rate. MicroRNAs (miRNAs) are involved in various physiological processes, but their role in chicken muscle growth remains unclear. We aimed to investigate the miRNAs and pathways participating in the muscle growth of chicken. MiRNA profiles of four SMB chickens and four DH chickens were detected by small RNA sequencing. A total of 994 known miRNAs were identified, among which gga‐miR‐1a‐3p, gga‐miR‐148‐3p and gga‐miR‐133a‐3p exhibited the highest enrichment in both breeds of chickens. Thirty‐two miRNAs were differently expressed between SMB and DH chickens. The differently expressed miRNAs were mainly associated with fatty acid metabolism, immunity and MAPK activation‐related processes. Kyoto encyclopaedia of genes and genomes (KEGG) analysis showed that miRNAs were involved in the immunity‐related and MAPK signalling pathways. Moreover, miR‐204 was downregulated in DH chicken compared with SMB chicken, and significantly inhibited the expression of MAP3K13, which is involved in the MAPK pathway. It was confirmed through luciferase reporter assays that miR‐204 specifically inhibited the activity of MAP3K13. Our results helped demonstrate the potential molecular mechanisms of muscle growth in chickens and provide valuable information for chicken breeding. [ABSTRACT FROM AUTHOR]

A novel pH‐sensitive fluorescent probe T2(OH)B was selected to theoretically investigate its excited state hydrogen bonding effects and excited state intramolecular proton transfer (ESIPT) process. First, it was verified that one intramolecular hydrogen bond is formed spontaneously in T2(OH)B itself. Given the geometrical changes, we further confirm that the hydrogen bond should be strengthened in the first excited state. When it comes to the photoexcitation process, we present the charge redistribution around hydrogen bonding moieties facilitate the ESIPT tendency. The increased electronic densities around acceptor promote the attraction of hydrogen protons. The potential energy barrier in the constructed potential energy curves reveals that the ESIPT process of the T2(OH)B system should be ultrafast. And comparing several nonpolar solvents, we deem solvent polarity plays little role in the ESIPT reaction. Furthermore, we also search the S1‐state transition state structure along with the ESIPT path, based on which we simulate the intrinsic reaction coordinate path. We not only confirm the ESIPT mechanism presented in this work but also clarify the ultrafast excited state process and explain previous experiment. We sincerely hope that our theoretical work could guide novel applications based on the T2(OH)B system in future. [ABSTRACT FROM AUTHOR]

Investigation into the temperature dependence of the mechanical behavior of ultra‐coarse grained cemented carbide materials is highly demanded due to its service conditions of concurrent applied stress and high temperature. In the present study, based on the designed experiments and microstructural characterization combined with crystallographic analysis, the evolution of slip systems, motion and interaction of dislocations with temperature are quantified for the WC hard phase. Mechanisms are proposed for the formation of the sessile dislocations in the main slip systems at the room temperature and the glissile dislocations in the new slip systems activated at high temperatures. Furthermore, the correlation of the plastic strain and fracture toughness with the temperature‐dependent slip activation, dislocation reaction and transformation is explained quantitatively. Enlightened by the present findings, potential approach to enhance the high‐temperature strength of ultra‐coarse cemented carbides based on WC strengthening was suggested. [ABSTRACT FROM AUTHOR]

There is intensive searching for superhard materials in both theoretical and experimental studies. Refractory and transition metal carbides are typical materials with high hardness. In this study, first‐principles calculations were performed first to analyze the electronic structures and mechanical properties of the tungsten‐carbide‐based compounds. The results indicated that tungsten carbide could be hardened by alloying elements with high work functions to tailor the Fermi level and electron density. Guided by the calculations, a new type of tungsten carbide alloyed with Re was synthesized. The Young's modulus and hardness of the Re‐alloyed tungsten carbide are increased by 31% and 44%, respectively, as compared with those of tungsten carbide. This study provides a new methodology to design superhard materials on a feasible electronic base using work function as a simple guiding parameter. [ABSTRACT FROM AUTHOR]

Given the tremendous potential applications of excited state intramolecular proton transfer (ESIPT) systems, ESIPT molecules have received widespread attention. In this work, based on density functional theory (DFT) and time‐dependent DFT (TDDFT) methods, we theoretically study the excited state dynamical behaviors of salicyladazine (SA) molecules. Our simulated results show that the double intramolecular hydrogen bonds of SA are strengthened in the S1 state via exploring bond distances, bond angles, and infrared (IR) vibrational spectra. Exploring the frontier molecular orbitals (MOs), we confirm that charge redistributions indeed have effects on excited state dynamical behaviors. The increased electronic densities on N atoms and the decreased electronic densities on O atoms imply that charge redistribution may trigger the ESPT process. Analyzing the constructed S0‐state and S1‐state potential energy surfaces (PESs), we confirm that only the excited state single proton transfer reaction can occur although SA possesses two intramolecular hydrogen bonds. In this work, we clarify the specific ESIPT mechanism, which may facilitate developing novel applications based on the SA system in future. [ABSTRACT FROM AUTHOR]

Given the tremendous potential of fluorescence sensors in recent years, in this present work, we theoretically explore a novel fluorescence chemosensor [2‐(2‐Hydroxy‐phenyl)‐1H‐benzoimidazol‐5‐yl]‐phenyl‐methanone (HBPM) about its excited state behaviors and probe‐response mechanism. Using density functional theory (DFT) and time‐dependent density functional theory (TDDFT) methods, we explore the S0‐state and S1‐state hydrogen bond dynamical behaviors and confirm that the strengthening intramolecular hydrogen bond in the S1 state may promote the excited state intramolecular proton transfer (ESIPT) reaction. In view of the photoexcitation process, we find that the charge redistribution around the hydroxyl moiety plays important roles in providing driving force for ESIPT. And the constructed potential energy curves further verify that the ESIPT process of HBPM should be ultrafast. That is the reason why the normal HBPM fluorescence cannot be detected in previous experiment. Furthermore, with the addition of fluoride anions, the exothermal deprotonation process occurs spontaneously along with the intermolecular hydrogen bond O–H⋯F. It reveals the uniqueness of detecting fluoride anions using HBPM molecules. As a whole, the fluoride anions inhibit the initial ESIPT process of HBPM, which results in different fluorescence behaviors. This work presents the clear ESIPT process and fluoride anion‐sensing mechanism of a novel HBPM chemosensor. [ABSTRACT FROM AUTHOR]

In the present work, three novel phenols (10a,11‐dihydro‐4bH‐indeno[1,2‐b]quinolin‐4‐ol (1), 5,6‐dihydro‐benzo[c]acridin‐1‐ol (2), and 5,5,7,7a‐tetrahydro‐4aH‐13‐aza‐benzo[3,4]cyclohepta[1,2‐b]naphthalene‐1‐ol (3)) have been explored theoretically in detail. Using density functional theory (DFT) and time‐dependent DFT (TDDFT) methods, we inquire into the intramolecular hydrogen‐bonding interactions and the excited‐state intramolecular proton transfer (ESIPT) process. Exploring the steady‐state absorption and emission spectra under TDDFT/B3LYP/TZVP theoretical level in acetonitrile solvent, our calculated results demonstrate an experimental phenomenon. Based on analysis of the variations of geometrical parameters and infrared (IR) vibrational spectra, we confirm that O–H⋯N should be strengthened in the S1 state. Investigating the frontier molecular orbitals (MOs) and the charge density difference (CDD) maps, it can be confirmed that the charge redistribution facilitates the tendency of the ESIPT process for 1, 2, and 3 systems. By constructing potential energy curves, we confirm that the proton transfer should occur in the S1 state. In particular, the ESIPT for 2 and 3 systems are nonbarrier processes in the S1 state, which confirms that ESIPT should be exothermal spontaneously. This work explains previous experimental results and makes a reasonable assumption about the ESIPT mechanism for 1, 2 and 3 systems. We sincerely hope our work can facilitate understanding and promoting applications about them in future. The intramolecular hydrogen bond of 1, 2, and 3 compounds should be strengthened in the S1 state. By exploring frontier molecular orbitals and charge density difference, the charge redistribution can be confirmed to facilitate the excited‐state intramolecular proton transfer (ESIPT) tendency. The ESIPT reaction for 1 compound demonstrates a low potential barrier, while that for 2 and 3 compounds should be exothermal spontaneously. [ABSTRACT FROM AUTHOR]

The microstructure evolution and changes in the structures of crystal defects of the nanocrystalline WC–Co composite in the process of uniaxial compression were studied by simulations at both room and high temperatures. The deformation processes were demonstrated as a function of stress and temperature for the stages prior to and after yielding of the composite. The Peierls stresses were evaluated for Co and WC dislocations with increasing temperature. The deformation mechanisms for each stage of the stress–strain curve were disclosed, in which the effect of temperature was clarified. It was found that with the increase of stress, from elastic deformation to plastic deformation then to yielding of the composite, the dominant mechanisms are grain boundary migration, formation and motion of dislocations in Co, concurrent motion and reaction of dislocations in Co and WC, and then rotation of WC grains in combination with motion of Co and WC dislocations. At the yielding stage, sliding of WC grain boundaries plays an increasingly important role in the contribution to plastic deformation at high temperatures. With strain the proportion of mobile dislocations decreases, and dislocations pile up at triple junctions of WC grains, WC/WC grain boundaries and WC/Co phase boundaries in priority order, leading to the nucleation and propagation of microcracks in these regions. Evolutions of microstructure and crystal defects in the nanocrystalline WC–Co composite during room‐ and high‐temperature deformations were studied using molecular dynamics simulations. [ABSTRACT FROM AUTHOR]

In this work, density functional theory (DFT) and time‐dependent DFT (TDDFT) methods were used to investigate the excited‐state dynamics of the excited‐state hydrogen‐bonding variations and proton transfer mechanism for a novel white‐light fluorophore 2‐(4‐[dimethylamino]phenyl)‐7‐hyroxy‐6‐(3‐phenylpropanoyl)‐4H‐chromen‐4‐one (1). The methods we adopted could successfully reproduce the experimental electronic spectra, which shows the appropriateness of the theoretical level in this work. Using molecular electrostatic potential (MEP) as well as the reduced density gradient (RDG) versus the product of the sign of the second largest eigenvalue of the electron density Hessian matrix and electron density (sign[λ2]ρ), we demonstrate that an intramolecular hydrogen bond O1–H2···O3 should be formed spontaneously in the S0 state. By analyzing the chemical structures, infrared vibrational spectra, and hydrogen‐bonding energies, we confirm that O1–H2·O3 should be strengthened in the S1 state, which reveals the possibility of an excited‐state intramolecular proton transfer (ESIPT) process. On investigating the excitation process, we find the S0 → S1 transition corresponding to the charge transfer, which provides the driving force for ESIPT. By constructing the potential energy curves, we show that the ESIPT reaction results in a dynamic equilibrium in the S1 state between the forward and backward processes, which facilitates the emission of white light. Highlights: The excited state dynamical equilibrium in ESIPT process of 1 compound facilitates mingling white light emitting. [ABSTRACT FROM AUTHOR]

In this work, density functional theory (DFT) and time‐dependent density functional theory (TDDFT) methods are used to explore the excited‐state intramolecular proton transfer (ESIPT) mechanism of a novel system 4′‐dimethylaminoflavonol (DAF). By analyzing the molecular electrostatic potential (MEP) surface, we verify that the intramolecular hydrogen bond in DAF exists in both the S0 and S1 states. We calculate the absorption and emission spectra of DAF in two solvents, which reproduce the experimental results. By comparing the bond lengths, bond angles, and relative infrared (IR) vibrational spectra involved in the hydrogen bonding of DAF, we confirm the hydrogen‐bond strengthening in the S1 state. For further exploring the photoexcitation, we use frontier molecular orbitals to analyze the charge redistribution properties, which indicate that the charge transfer in the hydrogen‐bond moiety may be facilitating the ESIPT process. The constructed potential energy curves in acetonitrile and methylcyclohexane solvents with shortened hydrogen bond distances demonstrate that proton transfer is more likely to occur in the S1 state due to the lower potential barrier. Comparing the results in the two solvents, we find that aprotic polar and nonpolar solvents seem to play similar roles. This work not only clarifies the excited‐state behaviors of the DAF system but also successfully explains its spectral characteristics. Hydrogen bond should be formed in the S0 state for 4′‐dimethylaminoflavonol (DAF), as shown via Atoms in Molecules (AIM) analysis. The intramolecular hydrogen bond of DAF should be strengthened in the S1 state, which provides the tendency for the excited‐state intramolecular proton transfer (ESIPT) reaction. The charge redistribution and low potential energy barriers of DAF facilitate the ESIPT reaction. [ABSTRACT FROM AUTHOR]

A novel 3‐hydroxyflavone derivative, 4‐methoxy‐3‐hydroxyflavone (4M3HF), is theoretically investigated regarding its excited state intramolecular proton transfer (ESIPT) mechanism based on density functional theory (DFT) and time‐dependent DFT (TDDFT) methods. By comparing the solvent polarity, we selected acetonitrile and toluene in this work. First, based on atoms in molecules (AIM) analyses, we verified the formation of intramolecular hydrogen bond of the 4M3HF structure. On investigating the geometrical parameters (i.e., bond lengths and bond angles), we found that the hydrogen bond strength should be enhanced in the S1 state. By calculating the infrared vibrational spectra, we confirmed the strengthening of the intramolecular hydrogen bond in the S1 state. We further studied the excitation process using the frontier molecular orbitals method, based on which we concluded that the charge redistribution in solvents facilitates the ESIPT tendency. For exploring the ESIPT behavior, we constructed the potential energy curves along with ESIPT paths in both solvents (acetonitrile and toluene). We found that low potential energy barriers facilitate the ESIPT process in the 4M3HF system, which was also verified by searching the transition state (TS) structure. Comparing these two solvents, we concluded that solvent effects play little role in the ESIPT reaction in the 4M3HF system. And we could successfully explain the previous experimental result. The intramolecular hydrogen bond of the 4M3HF structure should be strengthened in the S1 state in both acetonitrile and toluene. The charge redistribution of the hydrogen‐bonding moieties of 4M3HF system provides the tendency of ESIPT reaction. By constructing the potential energy curves and searching the TS structures of the 4M3HF system, we clarify the ESIPT mechanism and conclude that the solvent effects play little role in the ESIPT reaction. [ABSTRACT FROM AUTHOR]

Abstract: In this present work, using density functional theory and time‐dependent density functional theory methods, we theoretically study the excited‐state hydrogen bonding dynamics and the excited state intramolecular proton transfer mechanism of a new 2‐phenanthro[9,10‐d]oxazol‐2‐yl‐phenol (2PYP) system. Via exploring the reduced density gradient versus sign(λ2(r))ρ(r), we affirm that the intramolecular hydrogen bond O1‐H2⋯N3 is formed in the ground state. Based on photoexcitation, comparing bond lengths, bond angles, and infrared vibrational spectra involved in hydrogen bond, we confirm that the hydrogen bond O1‐H2⋯N3 of 2PYP should be strengthened in the S1 state. Analyses about frontier molecular orbitals prove that charge redistribution of 2PYP facilitates excited state intramolecular proton transfer process. Via constructing potential energy curves and searching transition state structure, we clarify the excited state intramolecular proton transfer mechanism of 2PYP in detail, which may make contributions for the applications of such kinds of system in future. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, we theoretical study the sensing mechanism of a new fluoride chemosensor (E)‐2‐(2‐(dimethylamino)ethyl)‐6‐(4‐hydroxystyryl)‐1H‐benzo[de]‐isoquinoline‐1,3(2H)‐dione (the abbreviation is NIM). Based on density functional theory and time‐dependent density functional theory methods, the fluoride anion response mechanism has been confirmed via constructing potential energy curve. The exothermal deprotonation process along with the intermolecular hydrogen bond O–H···F reveals the uniqueness of detecting F−. After capturing hydrogen proton forming NIM‐A anion configuration, a new absorption peak around 655 nm appears in dimethyl sulfoxide solvent. In addition, the emission of NIM can be quenched when adding F− has been also confirmed. Due to the twisted intramolecular charge transfer character NIM‐A‐S1 form, we further verify the experimental phenomenon. The theoretical electronic spectra (vertical excitation energies and fluorescence peak) reproduced previous experimental results (ACS Appl. Mater. Interfaces 2014, 6, 7996), which not only reveals the rationality of our theoretical level used in this work but also confirms the correctness of geometrical attribution. In view of the excitation process, the strong intramolecular charge transfer process of S0 → S1 transition explain the redshift of absorption peak for NIM with the addition of fluoride anion. This work presents a straightforward sensing mechanism (deprotonation process) of fluoride anion for the novel NIM chemosensor. [ABSTRACT FROM AUTHOR]

In the present work, using density functional theory and time-dependent density functional theory methods, we investigated and presented the excited-state intramolecular proton transfer (ESIPT) mechanisms of a novel Compound 1 theoretically. Analyses of electrostatic potential surfaces and reduced density gradient (RDG) versus sign(λ2)ρ, we confirm the existence of intramolecular hydrogen bond O1-H2···N3 for Compound 1 in the S0 state. Comparing the primary structural variations of Compound 1 involved in the intramolecular hydrogen bond, we find that O1-H2···N3 should be strengthened in the S1 state, which may facilitate the ESIPT process. Concomitantly, infrared (IR) vibrational spectra analyses further verify the stability of hydrogen bond. In addition, the role of charge transfer interaction has been addressed under the frontier molecular orbitals, which depicts the nature of electronical excited state and supports the ESIPT reaction. The theoretically scanned and optimized potential energy curves according to variational O1-H2 coordinate demonstrate that the proton transfer process should occur spontaneously in the S1 state. It further explains why the emission peak of Compound 1-enol was not reported in previous experiment. This work not only presents the ESIPT mechanism of Compound 1 but also promotes the understanding of this kind of molecules for further applications in future. [ABSTRACT FROM AUTHOR]

Abstract: We present a theoretical investigation about the excited state dynamical mechanism of 2‐(4′‐N,N‐dimethylaminophenyl)‐imidazo[4,5‐c]pyridine (DMAPIP‐c). Within the framework of density functional theory and time‐dependent density functional theory methods, we reasonably repeat the experimental electronic spectra, which further confirm the theoretical level used in this work is feasible. Given the best complex model, 3 methanol (MeOH) solvent molecules should be connected with DMAPIP‐c forming DMAPIP‐c‐MeOH complex in both ground state and excited state. Exploring the changes about bond lengths and bond angles involved in hydrogen bond wires, we find the O7‐H8···N9 one should be largely strengthened in the S1 state, which plays an important role in facilitating the excited state intermolecular proton transfer (ESIPT) process. In addition, the analyses about infrared vibrational spectra also confirm this conclusion. The redistribution about charges distinguished via frontier molecular orbitals based on the photoexcitation, we do find tendency of ESIPT reaction due to the most charges located around N9 atom in the lowest unoccupied molecular orbital. Based on constructing the potential energy curves of both S0 and S1 states, we not only confirm that the ESIPT process should firstly occur along with hydrogen bond wire O7‐H8···N9, but also find a low potential energy barrier 8.898 kcal/mol supports the ESIPT reaction in the S1 state forming DMAPIP‐c‐MeOH‐PT configuration. Subsequently, DMAPIP‐c‐MeOH‐PT could twist its dimethylamino moiety with a lower barrier 3.475 kcal/mol forming DMAPIP‐c‐MeOH‐PT‐TICT structure. Our work not only successfully explains previous experimental work but also paves the way for the further applications about DMAPIP‐c sensor in future. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we mainly focus on the excited‐state intramolecular proton transfer mechanism of a new molecule 9,10‐dihydroxybenzo[h]quinoline (9‐10‐HBQ). Within the framework of density functional theory and time‐dependent density functional theory methods, we have theoretically investigated its excited‐state dynamical process and our theoretical results successfully reappeared previous experimental electronic spectra. The ultrafast excited‐state intramolecular proton transfer process occurs in the first excited state (S1 state) forming 9‐10‐HBQ‐PT1 structure without potential energy barrier along with hydrogen bond (O3–H4···N5). Then the second proton may transfer via another intramolecular hydrogen bonded wire (O1–H2···N3) with a moderate potential energy barrier (about 7.69 kcal/mol) in the S1 state forming 9‐10‐HBQ‐PT2 configuration. After completing excited‐state dynamical process, the molecule on the first excited electronic state would come back to the ground state. We not only clarify the excited‐state dynamical process for 9‐10‐HBQ but also put forward new predictions and successfully explain previous experimental results. [ABSTRACT FROM AUTHOR]

The excited-state intramolecular proton transfer (ESIPT) mechanism of a new compound ( E)-1-((2,2-diphenylhydrazono)methyl)naphthalen-2-ol ( EDMN) sensor, reported and synthesized by Mukherjee et al. [ Sensors Actuat. B-Chem. 2014, 202, 1190], is investigated in detail theoretically. The calculations on primary bond lengths, bond angles, and the corresponding infrared (IR) vibrational spectra and hydrogen-bond energy involved in intramolecular hydrogen bond between the S0 and S1 states confirm that the intramolecular hydrogen bond is strengthened in the S1 state, which reveals the tendency of ESIPT reaction. The fact that the experimental absorption and emission spectra are well reproduced demonstrates the rationality and effectiveness of the time-dependent density functional theory (TDDFT) level of theory we adopt here. Furthermore, intramolecular charge transfer based on the frontier molecular orbitals (MOs) gives indication of the ESIPT reaction. The constructed potential energy curves of both the S0 and S1 states while keeping the O─H distance of EDMN fixed at a series of values are used to illustrate the ESIPT process. The lower barrier of ~3.934 kcal/mol in the S1 state potential energy curve (lower than the 8.254 kcal/mol in the S0 state) provides the transfer mechanism. [ABSTRACT FROM AUTHOR]

In this study, poly(vinylidene fluoride) (PVDF)/polyhedral oligomeric silsesquioxanes (POSS) nanofibrous membranes are prepared through electrospun process. Field emission scanning electron microscope images clearly show that PVDF/POSS membranes have interconnected multi fibrous layers with ultrafine porous structures. The average fiber diameter and crystallinity of PVDF/POSS membranes are lesser than that of pure PVDF membrane. Thermal stability and electrolyte uptake of blend membranes increase with increasing POSS content. Finally, PVDF/POSS membranes are soaked in a liquid electrolyte to form the polymer electrolytes and are assembled in coin cells to test their electrochemical properties such as ionic conductivity, interfacial characteristics, and electrochemical stability windows. The ionic conductivity improves with increasing POSS content and the highest ionic conductivity reaches 2.91 × 10−3 S/cm at room temperature. It is also worth mention that the composite polymer electrolytes show low interfacial resistance and high electrochemical stability window of 5.6 V (vs. Li+ /Li) with storage time. POLYM. COMPOS., 38:629-636, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

As a typical alkaline earth metal carbide, lithium carbide (Li2C2) has the highest theoretical specific capacity (1400 mAhg-1) among all the reported lithium-containing cathode materials for lithium ion batteries. Herein, the feasibility of using Li2C2 as a cathode material was studied. The results show that at least half of the lithium can be extracted from Li2C2 and the reversible specific capacity reaches 700 mAhg-1. The C≡C bond tends to rotate to form C4 (C≡C···C≡C) chains during lithium extraction, as indicated with the first-principles molecular dynamics (FPMD) simulation. The low electronic and ionic conductivity are believed to be responsible for the potential gap between charge and discharge, as is supported with density functional theory (DFT) calculations and Arrhenius fitting results. These findings illustrate the feasibility to use the alkali and alkaline earth metal carbides as high-capacity electrode materials for secondary batteries. [ABSTRACT FROM AUTHOR]

WC-Co cemented carbides were prepared by liquid-state sintering of in situ synthesized composite powders with a constant Co content but different carbon concentrations, and with different size scales of VC particles as grain-growth inhibitor. With an optimized carbon addition and doping with microscale VC particles, an ultrahigh fracture strength with a mean value above 5000 MPa was achieved for cemented carbides. By detailed crystallographic analysis of the configuration and interactions of the WC, Co and VC phases, the effects of VC particle size on the microstructure and mechanical properties of cemented carbides are identified. The mechanisms by which the fracture strength depends on the VC particle size contain the effects on the changes in Co binder distribution, atomic matching at the phase boundary and WC grain size. The dominant factors for ultrahigh fracture strength of cemented carbides are proposed. [ABSTRACT FROM AUTHOR]

High‐quality japonica rices Yujing 6 and Fangxin 4 were cultured under ambient night temperature (ANT, 19.7°C) and high night temperature (HNT, 26.7°C) in a greenhouse for the analysis of amyloplast development and grain quality during the grain‐filling stage. Results indicated that the HNT treatment had distinct effects on the grain‐filling rate of Yujing 6 and Fangxin 4 1–10 days after anthesis. HNT increased the rate of grain filling by 9.89–40.45% and decreased the accumulation of grain‐filling matter, resulting in inferior appearance and poor milling qualities (e.g., brown rice rate, milled rice rate, head rice rate, imperfect rice rate, chalky rice rate, and chalkiness degree). Results from a rapid viscosity analyzer showed that the HNT treatment decreased the paste viscosity, depending on the rice cultivar. Differential scanning calorimetry results indicated that the gelatinization temperatures of HNT such as onset temperature, peak temperature, and final temperature were all significantly higher than those of ANT. However, HNT had no distinct effects on the X‐ray diffraction pattern of rice starch. [ABSTRACT FROM AUTHOR]

Octenyl succinic starch esters were prepared from 12 strains of native indica rice starches with AM contents (AC) of 1.65-27.15%. The paste properties and emulsification were also investigated to evaluate the effect of ACs on starch properties. Results indicated that the degree of substitution for octenyl succinic starch ester were 0.0212-0.0252. Rapid visco analyzer (RVA) parameters demonstrated that octenyl succinic starch esters had higher relative viscosities than the native counterparts. Moreover, AC correlated negatively with the major RVA parameters (e.g. peak viscosity and breakdown viscosity). Compared with the native starches, octenyl succinic starch esters had higher paste clarity, decreased retrogradation, better freeze-thaw stability, and excellent gel texture, depending on ACs of the native starches. SEM showed that the gels from octenyl succinic starch esters had less and smaller pores, however, the gels from native starches changed to sponge-like structure after three freezing/thawing cycles. Fluorescence photomicrographs and droplet size distribution indicated that octenyl succinic starch ester was an effective emulsifier for oil-in-water emulsions. This type of modified rice starch can potentially be employed as a thickener and emulsifier in frozen foods. [ABSTRACT FROM AUTHOR]

The advancement of Eu2+‐activated luminescent materials tailored to exhibit a range of properties is crucial for addressing the specific demands of various application fields. However, the lack of suitable lattice sites in numerous compounds for stable Eu2+ incorporation restricts their potential for diverse optical properties. Herein, a facile strategy of carbon and hydrogen coreduction utilizing graphite crucibles is proposed to effectively achieve the impressive luminescence of Eu2+ at trivalent Y sites in Rb3Y(PO4)2:Eu phosphors. Rb3Y(PO4)2:Eu exhibits blue‐violet emission when Eu2+ predominantly occupies the Rb1 and Rb2 sites. Inspiringly, by facilitating the reduction of more Eu3+ to Eu2+, a yellow emission band at 550 nm arising from Eu2+ at Y sites emerges, enabling the realization of single‐component white‐emitting and yellow‐emitting Rb3Y(PO4)2:Eu phosphors. The diverse luminescent properties of Rb3Y(PO4)2:Eu expand its potential applications in different white light source devices and optical thermometry. This work presents an innovative synthetic strategy to develop remarkable Eu2+ luminescence at trivalent cation sites, thereby broadening the optical properties of the material and enabling multifunctional applications. [ABSTRACT FROM AUTHOR]

Please cite this paper as: Song et al. (2012) Comparison of pandemic and seasonal influenza A infections in pediatric patients: were they different?. Influenza and Other Respiratory Viruses 6(1), 25-27. This retrospective cohort study revealed that the presence of pandemic H1N1 influenza resulted in a 77.7% increase of patient visits in the emergency department for influenza like illnesses and a 67.2% increase of hospital days in our hospital by comparing to a regular influenza season (2008-2009 season). However, median length of hospital stay was no different in either period (pandemic: 3 days versus seasonal: 4 days, P = 0.06). Except for the patients hospitalized for pandemic H1N1 influenza ( n = 111) were older (median age: 4.7 years versus 1.6 years, P = 0.04) and tended to have pre-existing asthma (21.6% versus 9.0%, P = 0.07) than those hospitalized for seasonal influenza A infections ( n = 44), this study found no significant difference between the two comparison groups with regards of other clinical and epidemiological features. [ABSTRACT FROM AUTHOR]