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Optical thermometry based on fluorescence intensity ratio (FIR) has garnered significant interest among researchers due to its rapid, non-contact, and high sensitivity characteristics. In this study, stoichiometric NaYb(WO 4) 2 phosphors, doped with varying concentrations of Er3+, were successfully synthesized using the high-temperature solid-state method. Under both 980 nm and 266 nm excitation, the samples exhibited strong green and very weak red upconversion (UC) and downconversion (DC) luminescence. The structural and morphological properties of the prepared samples were thoroughly characterized using techniques such as X-ray diffraction (XRD), XRD Rietveld refinement, scanning electron microscopy (SEM), and Fourier transform infrared (FT-IR) spectroscopy. The phosphors demonstrated high-purity UC and DC emission, with maximum green-to-red ratios of 60.9 and 77.0, respectively. This discovery opens up vast possibilities for their application as pure green color converters. The UC emission of Er3+ ions in the stoichiometric NaYb(WO 4) 2 phosphor was identified as a two-photon UC process, as evidenced by the relationship between the luminescence intensity and the excitation power of the sample. Moreover, the temperature-dependent emission spectra of UC and DC were monitored, and investigated the fluorescence intensity ratios (FIRs) of 2H 11/2 → 4I 15/2 and 4S 3/2 → 4I 15/2 transitions of Er3+ ions to assess the optical temperature sensing behavior of NaYb(WO 4) 2 :Er3+. The experimental results revealed that the maximum absolute sensitivities (S A) of NaYb(WO 4) 2 phosphors were 0.0120 K-1 (UC) and 0.0077 K-1 (DC), and the maximum relative sensitivities (S R) were 0.0089 K-1 (UC) and 0.0092 K-1 (DC), respectively. These findings highlight the promising of Er3+-doped Yb3+ stoichiometric NaYb(WO 4) 2 phosphors in optical temperature sensors. • The up/down conversion emissions of self-activated NaYb(WO 4) 2 phosphors have been investigated. • The phosphors demonstrate high-purity up/down conversion emissions. • The temperature sensing behavior of the phosphors was evaluated based on the FIRs of Er3+. • The maximum absolute sensitivity determined for UC and DC were 0.0120 K-1 and 0.0077 K-1, respectively. [ABSTRACT FROM AUTHOR]

Yb3+-doped mixed laser crystals are widely recognized as materials capable of generating ultrashort pulses and have garnered significant attention in recent times. In this study, we thoroughly examined the structure and spectroscopic properties of a novel mixed molybdate crystal, Yb:KNGM. Notably, we made detailed observations of an exceptionally broad absorption band with a full width at half maximum (FWHM) of 78 nm. The broad absorption band indicates that the commercially available InGaAs laser diode (LD) can be effectively utilized for high pumping efficiency purpose. The absorption and emission cross-section at 967 and 1014 nm were calculated to be 1.56 × 10−20 cm2 and 2.05 × 10−20 cm2, respectively. The FWHM of the emission band reaches a substantial range of 62 nm, making it highly conducive to the production of ultrashort pulse lasers. The bandgap (E g) was fitted as 3.26 eV by Tauc formula. Positive gain cross-section can be achieved while the β is only higher than 0.2 and a large FWHM of 41 nm was discovered when β is 0.5. The aforementioned merits provide compelling evidence that Yb:KNGM crystal holds great promise as a laser crystal for the application of wild tunable and ultrashort pulse lasers pumped by LD. • A novel Yb3+ doped mixed double molybdate crystal, Yb:KNGM, was grown by Cz method. • The broad absorption band with FWHM of 78 nm was derived from the mixed crystal. • The emission cross-section at 1014 nm were calculated to be 2.05 × 10−20 cm−1. • Positive gain cross section can be achieved while the β is only higher than 0.2. [ABSTRACT FROM AUTHOR]

• Water resource management requires engagement of multiple socioeconomic sectors. • Regional water security level approached the water scarcity threshold by 2020. • Regional water resource security has been achieved, but future decades have risks. • Improving water-saving technology is instructive in water resource management. Water security is the backbone of regional development. However, it is generally compromised by the increasing competition for water resources between natural and social systems, especially in areas with limited water resources. Sustainable water planning requires a comprehensive analysis of supply and demand patterns, which is difficult owing to scale mismatches in data and methodologies. This study investigated the dynamics and interrelationships of water supply and demand in a semi-arid watershed of the Loess Plateau, China, by developing a system dynamics model that simulates water security during 1980–2020 and future changes under different climate, socioeconomic development, and inter-basin water diversion scenarios during 2021–2050. The results showed that (1) by the end of 2020, the regional water security level gradually approached the water scarcity threshold indicated by the water deficit index surpassing 0; (2) under unfavorable climate and progressive socioeconomic growth conditions, up to 16 out of 30 years of simulation demonstrated water insecurity in the form of a net water quantity deficit; and (3) the water diversion project can offset such deficits in the short term, but potentially aggravates water insecurity risk by eliciting a more rapid socioeconomic growth pattern. The results indicate that curbing demand and improving water-saving technology are instructive in water resource management. For the Yanhe Watershed, the quantity and pattern of water diversion should be improved in the future to guarantee water resource security on a full temporal scale. We suggest a moderate socioeconomic growth rate to be more appropriate for this region and that efforts to solidify water use redlines and advancement in water-saving technologies are essential in the future. This study provides a scientific basis for the long-term evaluation of regional water security on a full timescale with tightly coupled hydrological components and a modeling framework for decision-makers to manage water resources sustainably. [ABSTRACT FROM AUTHOR]

The Loess Plateau is a typical ecologically sensitive area that can easily be perturbed by the effects of human activities and global climate change. Therefore, it is necessary to develop tools to monitor the environmental quality in the LP quickly and accurately. To reveal the spatio-temporal changes in environmental quality in the LP from 2000 to 2020, we used the Moderate-Resolution Imaging Spectroradiometer (MODIS) products on the Google Earth Engine platform and constructed the remote sensing ecological index (RSEI) through principal component analysis (PCA). Then, Sen–Mann–Kendall methods were applied to determine the changing trend of the environmental quality of the LP. Finally, natural and anthropogenic factors affecting the environmental quality were probed using a geographical detector model. The results showed that: (1) the average RSEI values in 2000, 2010 and 2020 were 0.396, 0.468 and 0.511, respectively, displaying an upward trend from 2000 to 2020, with a growth rate of 0.005 year − 1 . The overall environment quality was moderate (0.4–0.6). (2) In terms of spatial distribution, the environmental quality was excellent in the southeast and poor in the northwest of the LP. The areas with improved environmental quality (84.51%) were located in all the counties, whereas the areas with degraded environmental quality (8.11%) occurred in the north and southeast of the study area. (3) Greenness, heat, wetness, dryness and land use types were prominent factors affecting RSEI throughout the study period; additionally, the total industrial gross domestic product showed a growing influence. The contribution of multi-factor interaction was stronger than that of single factors. The results will provide a reference and a new research perspective for local environmental protection and regional planning. [ABSTRACT FROM AUTHOR]

• The increasing trend of vapor pressure deficit (VPD) change in 1997–2020 is ten times higher than in 1981–1996. • Increasing VPD promoted cropland and grassland growth in Arid, while inhibited the growth of shrubland. • Significant positive or negative difference in the sensitivity to VPD for the same vegetation under different climatic zones. • The vast majority of vegetation showed a significant increase in the inter-annual trend of the sensitivity to VPD. • The relationship of higher sensitivity with lower VPD is not stable under different vegetation and climatic zones. Vapor pressure deficit (VPD) shows significant spatial and temporal variability in the context of global climate change, which is important for studying the implications of climate change on the structure and function of ecosystems to analyze the effects of VPD on vegetation dynamics. Spatial patterns of vegetation sensitivity to VPD have been recently investigated, however, the feedback of different vegetation types to VPD may vary depending on physiological characteristics, it is unclear how different types influence the sensitivity to VPD. In this study, the ERA5-Land reanalysis time-series dataset was used to analyze the spatial and temporal trends of VPD under different vegetation types. It was found that VPD showed an increasing trend in vegetated areas over the past 20 years with large spatial heterogeneity, generally increasing with drying conditions. On this basis, the spatial patterns of vegetation sensitivity to VPD and temporal trends in sensitivity were evaluated over the past 20 years in China using the enhanced vegetation index (EVI) and near-infrared reflectance of vegetation (NIRv) which can describe vegetation dynamics. The results show that the sensitivities under the two indices have high spatial consistency, with northeastern and central China showing positive sensitivities and southern China showing negative sensitivities, respectively. The positive sensitivities are relatively high for Deciduous Broadleaf Forests (DBF), Deciduous Needleleaf Forests (DNF), Grasslands (GL), and Croplands (CL) types, while the negative sensitivities are larger for Shrublands (SL) and Savannas (SA) types. Under different climatic zones, the sensitivity of CL and GL are independent of climatic zones (both showing positive), while the sensitivity of SL is negative in the Humid zone and positive in the Semi-Arid zone. Temporally, the sensitivity showed a slow increasing trend over the last 20 years. In terms of vegetation types, sensitivities of Evergreen Broadleaf Forests (EBF), DBF, GL and CL types showed a significant increasing trend (p < 0.05), except for the SL type, which showed a significant decreasing trend (p < 0.05). The trends of sensitivity are not affected by the differences in vegetation types (all of them show an increasing trend) under arid and semi-arid conditions, while dry sub-humid and humid have a greater impact on sensitivity trends. The finding of an overall increase in sensitivity suggests a mechanism of erratic change in vegetation growth under climate change. Notably, the increased sensitivity of certain vegetation types (especially GL and CL) suggests that these may become progressively vulnerable to increased VPD as global climate change persists, with the risk of moving from facilitation to inhibition of photosynthesis. [ABSTRACT FROM AUTHOR]

Understanding the spatial distribution of dead pine trees (DPTs) in mountainous areas is vital for diseased wood cleanup and the prediction of pine wilt disease. The study induced a deep learning (DL) model of convolutional neural networks (CNNs) for the DPT detection using unmanned aerial vehicle images. Two thousand manually labelled DPT and Non-DPT samples were collected to train (80%) and optimize (20%) the CNNs of AlexNet and GoogLeNet, and 768 samples from other three areas were used to predict the categories in Jinjiang, Fujian, southeastern China. The same dataset was used to compare the classification accuracy between CNNs and the traditional template matching (TM) method. In addition, the potential factors influencing the overall accuracy of the DL model for DPT detection were evaluated. Training results of AlexNet and GoogLeNet showed an accuracy of over 93.30% and 97.38% respectively for the top-1 test after the final training iteration. For the DPT classification in the prediction areas of pure forests, the TM method showed the 56–65% of overall accuracy while CNNs showed 65–80%. CNNs-based DPT detection was more accurate than the traditional TM method. Terrains and red broadleaf trees influence the CNNs-based DPT detection from aerial visible-images in mixed artificial forest and peaks areas. [ABSTRACT FROM AUTHOR]

Isosorbide-5-mononitrate (5-ISMN), an organic nitrate vasodilator, has been widely used worldwide to prevent angina pectoris for more than two decades. A simple and sensitive high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed and validated for the determination of 5-ISMN in human plasma. 13C6-5-ISMN is an internal standard, and 5-ISMN was extracted from human plasma (50 µL) with ethyl acetate (200 µL) by a simple liquid-liquid extraction method. The chromatographic separation was carried out on LC-20A (Shimadzu, Japan) using an analytical column ZORBAX XDB-C18 (4.6 × 50 mm, 5 µm), coupled with API 4000 tandem mass spectrometers in a multiple reaction monitoring (MRM) mode. The mobile phase was composed of acetonitrile (organic phase A) and 2 mM ammonium acetate in water (aqueous phase B) with an isocratic elution of A/B = 90 : 10 (v / v). The total run time was 3.5 min with a small injection volume (5 µL). This method was fully validated in every aspect of selectivity, linearity, accuracy, precision, matrix effect, extraction recovery, and different stabilities. It was proved that the calibration standards within the 5.00–1000 ng/mL concentration range were linear. The lower limit of quantification was 5.00 ng/mL for 5-ISMN. The intrabatch and interbatch accuracy (RE) ranged from −8.8% to 7.1% with precision between 2.4% and 6.6%. The mean values of 5-ISMN extraction recovery and matrix effect were 87.0% and 102.0%, respectively. The fully validated method was successfully applied for a bioequivalence clinical trial of oral 20 mg 5-ISMN tablets in healthy Chinese subjects. [ABSTRACT FROM AUTHOR]

Aims: The objectives were to investigate the pharmacokinetics, pharmacodynamics and safety of ilaprazole infusion in healthy subjects and patients with esomeprazole as positive control, and then recommend the dosage regimen for Phase 2b/3 studies. Methods: Three clinical studies were performed. First, 16 healthy subjects received infusion of ilaprazole 30 mg or esomeprazole 80 mg. Second, 12 healthy subjects received ilaprazole 20 mg followed by 10 mg once daily for 2 days. Finally, 20 patients with duodenal ulcers received ilaprazole 20 mg followed by 10 mg for 2 days or esomeprazole 40 mg twice daily for 3 days. Serial blood samples were collected and intragastric pH was recorded. Results: The mean percentages time of intragastric pH >6 was 63.6 and 51.7% for healthy subjects after receiving ilaprazole 30 mg and esomeprazole 80 mg. Linear pharmacokinetics was observed when the dose was increased to 30 mg but the effect was saturated. Ilaprazole 20 mg followed by 10 mg for 2 days provided higher plasma exposure in healthy subjects than patients, but the effect was comparable. After multiple administrations, ilaprazole provided similar effect to esomeprazole. Ilaprazole infusion was safe and well tolerated without serious adverse events. Conclusions: Ilaprazole provided comparable effect of pH control to esomeprazole, with lower dose and fewer times of administration. There was no significant difference of ilaprazole between healthy subjects and patients regarding intragastric acid inhibition. A loading dose of ilaprazole 20 mg followed by 10 mg once daily for 2 days was recommended for Phase 2b/3 studies. [ABSTRACT FROM AUTHOR]

Aim and background Proton pump inhibitors (PPIs) are the main drugs for the treatment of reflux esophagitis. Phase II clinical trials showed that, compared with Esomeprazole, the new PPI Ilaparazole is great in terms of efficacy for reflux symptoms relief and curling for esophagitis. The aim of this study was to confirm suitable dose of Ilaparazole in the treatment of reflux esophagitis. Methods This study used a randomized, double-blind, parallel positive drug control, multi-center design. A total of 537patients diagnosed as reflux esophagitis by gastroscopy were randomly divided into Ilaparazole group (n = 322, Ilaparazole 10 mg QD) and esomeprazole group (n = 215, Esomeprazole 40 mg QD). The patients in the two groups were treated for 8 weeks. Heartburn and reflux symptoms prior to treatment, and 2, 4 and 8 weeks after the treatment were assessed. Gastroscopy was performed after 4 weeks of treatment. Unhealed patients within 4 weeks underwent gastroscopy again at the end of 8 weeks. Results A total of 471 cases completed the treatment. In Esomeprazole and Ilaparazole groups. After 8 weeks treatment, the healing rate in Esomeprazole group and Ilaparazole group were 82.79% (94.94%) and 83.54% (92.50%), respectively. The corresponding rate difference [Ilaparazole-esomeprazole] was 0.75% (−2.44%) and the two-sided 95% CI was −5.72 to 7.22 (−6.90 to 2.01). The symptom disappearance rates for FAS (PPS) were 75.81% (82.02%) and 76.71% (80.36%) P = 0.8223 (0.7742). Adverse reactions related to the drugs were: 10.70% and 11.80%, (P = 0.7817). Conclusions The efficacy and safety of Ilaparazole (10 mg/day) in treating reflux esophagitis was similar to esomeprazole (40 mg/day). Ilaparazole (10 mg/day) can be used in the treatment of esophagitis. The clinical trial registration number of the study is NCT 02860624. [ABSTRACT FROM AUTHOR]

Background and Objective: Proton pump inhibitors (PPIs) are the main drugs for the treatment of reflux esophagitis. Previous studies have indicated ilaprazole to be safer and more effective in treating duodenal ulcers as compared with omeprazole. Being a novel PPI, ilaprazole may be used in the treatment of reflux esophagitis. The purpose of this study was to evaluate the safety and efficacy of ilaprazole tablets in the treatment of reflux esophagitis. Methods: This study used a randomized, double-blind, multi-center, active-comparison design. The patients were randomly divided into an ilaprazole group (10 mg once daily and 15 mg once daily) and an esomeprazole group (40 mg once daily). Both the groups were treated for 8 weeks. Heartburn and reflux symptoms prior to treatment, and 4 and 8 weeks after the treatment were assessed. Gastroscopy was performed after 4 and 8 weeks. The healing rate after 4 weeks treatment was compared. If esophagitis was healed at the end of 4 weeks, patients did not undergo gastroscopy at the end of 8 weeks. Results: Three hundred and twenty-five patients were enrolled in this study. The 4-week full analysis set (per-protocol set) healing rates in the esomeprazole 40-mg group, the ilaprazole 10-mg group, and the ilaprazole 15-mg group were: 71.43 % (78.89 %), 81.31 % (86.73 %), and 71.70 % (81.40 %), respectively, p = 0.1595 (0.4122); the 8-week healing rates were 84.76 % (93.33 %), 88.79 % (94.90 %), and 85.85 % (97.67 %), respectively, p = 0.6689 (0.4049). Drug-related adverse events rate were 10.48 %, 14.02 %, and 15.09 %, respectively, in the three groups ( p = 0.6114). Conclusion: The efficacy and safety of ilaprazole (10 mg/day, 15 mg/day) in treating reflux esophagitis was similar to esomeprazole (40 mg/day). Ilaprazole (10 mg/day) has a smaller dosage, hence it should be considered more in clinical uses. Trial registration: ClinicalTrials.gov NCT01107938. [ABSTRACT FROM AUTHOR]

Background and Objectives: Ilaprazole is a novel proton pump inhibitor that provides effective and long lasting inhibition of intragastric acid secretion. The objectives of this study were to investigate the pharmacokinetics, pharmacodynamics, and safety of intravenous ilaprazole after multiple administrations in healthy Chinese subjects. Methods: This was an open-label and multiple-dose clinical study. Ten healthy Chinese subjects received 10 mg ilaprazole infusion once daily for 5 days. Helicobacter pylori status was examined. Blood samples were collected and intragastric pH was recorded for 24 h. Safety was assessed throughout the study. Results: There was no accumulation after multiple administrations. The mean steady-state half-life and clearance were comparable to those following single administration. Ilaprazole provided sustainable and significant intragastric pH control in terms of percentage time at pH >4, pH >6 within 24 h and mean 24-h pH values. The pH value within 24 h was affected by Helicobacter pylori infection in subjects with continuous infusion. Intravenous ilaprazole was safe and there were no serious adverse events. Conclusion: Intravenous ilaprazole provided stable pharmacokinetics and pharmacodynamics at a dose of 10 mg once daily for 5 days, and was well tolerated in healthy subjects. [ABSTRACT FROM AUTHOR]

Aim Angiotensin receptor antagonists ( ARBs) and anti-oxidants reduce urinary protein excretion and delay progression of immunoglobulin A ( IgA) nephropathy. We investigated the efficacy and safety of probucol (an anti-oxidant) combined with valsartan (an ARB) on the progression of IgA nephropathy. Methods Patients with IgA nephropathy ( n = 69) were recruited from five centres and randomly assigned to a treatment group (750 mg/day probucol plus 160 mg/day valsartan) or a control group (160 mg/day valsartan) and were followed for 3 years. Results At baseline, the two groups in any measured clinical information were comparable. The primary endpoint (doubling serum creatinine) showed no significant difference between the two groups during 3-year follow-up. The secondary endpoint (50% reduction in 24-h urinary protein) occurred in 23 patients in the treatment group and 20 patients in the control group. The time to the secondary end-point was shorter in the treatment group than the control group (8.13 months vs 19.63 months, P = 0.019). However, at the 3-year follow-up, the 24-h urinary protein levels were not significantly different from the baseline levels ( P = 0.99 and P = 0.66, respectively). At the 1-year follow-up, plasma cholesterol in the treatment group was markedly lower than in the control group (4.12 ± 1.28 vs 5.03 ± 1.01, P = 0.02). Conclusion Kidney function remained stable and there was no significant difference in two group patients. Probucol combined with valsartan led to a more rapid decrease of 24-h urinary protein excretion than valsartan alone. However, the long-term effect needs further investigation. [ABSTRACT FROM AUTHOR]

The waiver of bioequivalence (BE) studies is well accepted for Biopharmaceutics Classification System (BCS) class I drugs in form of immediate-release solid oral products. This study aimed to assess whether the rapid dissolution profiles (≥85% in 30 min) was crucial to guarantee bioequivalence of isosorbide mononitrate (ISMN) and then established a clinically relevant dissolution specification (CRDS) for screening BE or non-BE batches. A physiologically based pharmacokinetic (PBPK) model was constructed by integrating clinical and non-clinical data by B2O simulator. The model was verified by an actual clinical study (NMPA registration number: CTR20191360) with 28 healthy Chinese subjects. Then a virtual BE study was simulated to evaluate the bioequivalence of 7 virtual batches of ISMN tablets with different dissolution profiles, and the CRDS was established by integrating the results. The simulated PK behavior of ISMN was comparable to the observed. Even though the batches with slower dissolution were not equivalent to a rapid dissolution profile (≥85% in 30 min), it was demonstrated these batches would exhibit the similar in vivo performance. Meanwhile, the in vitro dissolution specification time point and the percentage of drug release (75% in 45 min) proved to have clinical relevance. The virtual BE simulation by integrating in vitro dissolution profiles into the PBPK model provided a powerful tool for screening formulations, contributing to gaining time and reducing costs in BE evaluations. The virtual BE simulation of Isosorbide Mononitrate tablets with different dissolution profiles was performed by using PBPK modeling. It was proved that the rapid dissolution rate (≥85% in 30 min)wasnotnecessary to guarantee bioequivalence for BCS class Idrug and a clinically relevant dissolution specificationwas furtherestablished for screening the BE and non-BE batches. Image, graphical abstract [ABSTRACT FROM AUTHOR]