Conformational and static properties of tagged chains in solvents: effect of chain connectivity in solvent molecules.

Polymer chains immersed in different solvent molecules exhibit diverse properties due to multiple spatiotemporal scales and complex interactions. Using molecular dynamics simulations, we study the conformational and static properties of tagged chains in different solvent molecules. Two types of solvent molecules were examined: one type consisted of chain molecules connected by bonds, while the other type consisted of individual bead molecules without any bonds. The only difference between the two solvent molecules lies in the chain connectivity. Our results show a compression of the tagged chains with the addition of bead or chain molecules. Chain molecule confinement induces a stronger compression compared to bead molecule confinement. In chain solvent molecules, the tagged chain's radius of gyration reached a minimum at a monomer volume fraction of ∼0.3. Notably, the probability distributions of chain size remain unchanged at different solvent densities, irrespective of whether the solvent consists of beads or polymers. Furthermore, as solvent density increases, a crossover from a unimodal to a bimodal distribution of bond angles is observed, indicating the presence of both compressed and expanded regions within the chain. The effective monomer-solvent interaction is obtained by calculating the partial radial distribution function and the potential of the mean force. In chain solvents, the correlation hole effect results in a reduced number of nearest neighbors around tagged monomers compared to bead solvents. The calculation of pore size distribution reveals that the solvent nonhomogeneity induced by chain connectivity leads to a broader distribution of pore sizes and larger pore dimensions at low volume fractions. These findings provide a deeper understanding of the conformational behavior of polymer chains in different solvent environments.

Two-dimensional Janus SbTeBr/SbSI heterostructures as multifunctional optoelectronic systems with efficient carrier separation.

The stacking of two-dimensional (2D) materials is a highly effective approach in the design of high-performance optoelectronic devices. In this study, we propose a novel Janus monolayer-based 2D/2D van der Waals heterostructure (vdWH) called SbTeBr/SbSI. Starting from its most stable binding configuration, we systematically examined its electronic, optical, mechanical and dynamical properties. The SbTeBr/SbSI vdWH exhibits a type II band arrangement, with an indirect bandgap of 1.28 eV and strong light absorption capabilities in the visible range, achieving an absorption coefficient of 4 × 105 cm-1. These desirable properties suggest that SbTeBr/SbSI holds promise as a material for solar cells, potentially achieving a power conversion efficiency of 8.3%. The dipole-induced electric field in the SbTeBr/SbSI vdWH leads to significant differences in the mobilities of different carriers, which is a critical aspect in suppressing the recombination of photogenerated carriers. Additionally, according to the simulations of nonadiabatic molecular dynamics, a long electron-hole recombination time of 133 ps is predicted. Thus, the SbTeBr/SbSI heterostructure enables efficient charge separation, demonstrating its potential as a high-performance optoelectronic material.

Two-dimensional TiCl2: a high-performance anode material for Na-ion batteries with high capacity and fast diffusion.

Na-ion batteries (NIBs) have attracted a great deal of attention for large-scale electric energy storage due to their inherent safety, natural abundant resources, and low cost. The exploration of suitable anode materials is the major challenge in advancing NIB technology. On the basis of first-principles calculations, we systematically explore the potential performance of two-dimensional (2D) TiCl2 as an electrode material for NIBs. Monolayer TiCl2 can be easily exfoliated from the bulk structure with a small exfoliation energy of 0.64 J m-2. It shows good stability, as demonstrated by its high cohesive energy, positive phonon modes, and high thermal stability. Monolayer TiCl2 has high storage capacity (451.3 mA h g-1), low diffusion energy barrier (0.02-0.14 eV), moderate average open-circuit voltage (0.81 V), and small lattice change (2.37%). Moreover, bilayer TiCl2 can significantly enhance the Na adsorption strength but reduce the Na-ion diffusion ability. These results suggest that TiCl2 is a promising anode candidate for NIBs.

Hesperidin Anti-Osteoporosis by Regulating Estrogen Signaling Pathways.

Osteoporosis (OP) is distinguished by a reduction in bone mass and degradation of bone micro-structure, frequently resulting in fractures. As the geriatric demographic expands, the incidence of affected individuals progressively rises, thereby exerting a significant impact on the quality of life experienced by individuals. The flavonoid compound hesperidin has been subject to investigation regarding its effects on skeletal health, albeit the precise mechanisms through which it operates remain ambiguous. This study utilized network pharmacology to predict the core targets and signaling pathways implicated in the anti-OP properties of hesperidin. Molecular docking and molecular dynamics simulations were employed to confirm the stability of the interaction between hesperidin and the core targets. The effects of hesperidin on osteoblastic cells MC3T3-E1 were assessed using MTT, ELISA, alkaline phosphatase assay, and RT-qPCR techniques. Furthermore, in vivo experiments were conducted to determine the potential protective effects of hesperidin on zebrafish bone formation and oxidative stress response. The results demonstrate that network pharmacology has identified 10 key target points, significantly enriched in the estrogen signaling pathway. Hesperidin exhibits notable promotion of MC3T3-E1 cell proliferation and significantly enhances ALP activity. ELISA measurements indicate an elevation in NO levels and a reduction in IL-6 and TNF-α. Moreover, RT-qPCR analysis consistently reveals that hesperidin significantly modulates the mRNA levels of ESR1, SRC, AKT1, and NOS3 in MC3T3-E1 cells. Hesperidin promotes osteogenesis and reduces oxidative stress in zebrafish. Additionally, we validate the stable and tight binding of hesperidin with ESR1, SRC, AKT1, and NOS3 through molecular dynamics simulations. In conclusion, our comprehensive analysis provides evidence that hesperidin may exert its effects on alleviating OP through the activation of the estrogen signaling pathway via ESR1. This activation leads to the upregulation of SRC, AKT, and eNOS, resulting in an increase in NO levels. Furthermore, hesperidin promotes osteoblast-mediated bone formation and inhibits pro-inflammatory cytokines, thereby alleviating oxidative stress associated with OP.

Photogenerated carrier dynamics at the B4C3/g-C3N4 interface.

Developing van der Waals (vdW) heterostructures is an excellent approach for optimizing exceptional optoelectronic and photocatalytic properties of materials; therefore, researching the interface dynamics of charge carriers at the two-dimensional vdW heterojunction is of great significance. In this work, we perform time-dependent ab initio non-adiabatic molecular dynamics simulations to study the dynamics of charge transfer at the B4C3/g-C3N4 heterostructure. The simulations show that the charge transfer between B4C3/g-C3N4 layers is mainly caused by the non-adiabatic mechanism. The non-adiabatic mechanism leads to a higher charge-transfer efficiency and slows down the process of interlayer electron-hole recombination, thereby promoting the separation of photogenerated electron-hole pairs. Our investigation provides essential insights into understanding the dynamics of charge transfer for the B4C3/g-C3N4 heterostructure, which provides guidance for photocatalytic water splitting and optoelectrical applications.

Improved morbidity-based air quality health index development using Bayesian multi-pollutant weighted model.

BACKGROUND: The widely used Air Quality Index (AQI) has been criticized due to its inaccuracy, leading to the development of the air quality health index (AQHI), an improvement on the AQI. However, there is currently no consensus on the most appropriate construction strategy for the AQHI. OBJECTIVES: In this study, we aimed to evaluate the utility of AQHIs constructed by different models and health outcomes, and determine a better strategy. METHODS: Based on the daily time-series outpatient visits and hospital admissions from 299 hospitals (January 2016-December 2018), and mortality (January 2017-December 2019) in Guangzhou, China, we utilized cumulative risk index (CRI) method, Bayesian multi-pollutant weighted (BMW) model and standard method to construct AQHIs for different health outcomes. The effectiveness of AQHIs constructed by different strategies was evaluated by a two-stage validation analysis and examined their exposure-response relationships with the cause-specific morbidity and mortality. RESULTS: Validation by different models showed that AQHI constructed with the BMW model (BMW-AQHI) had the strongest association with the health outcome either in the total population or subpopulation among air quality indexes, followed by AQHI constructed with the CRI method (CRI-AQHI), then common AQHI and AQI. Further validation by different health outcomes showed that AQHI constructed with the risk of outpatient visits generally exhibited the highest utility in presenting mortality and morbidity, followed by AQHI constructed with the risk of hospitalizations, then mortality-based AQHI and AQI. The contributions of NO2 and O3 to the final AQHI were prominent, while the contribution of SO2 and PM2.5 were relatively small. CONCLUSIONS: The BMW model is likely to be more effective for AQHI construction than CRI and standard methods. Based on the BMW model, the AQHI constructed with the outpatient data may be more effective in presenting short-term health risks associated with the co-exposure to air pollutants than the mortality-based AQHI and existing AQIs.

A rare case of bladder cancer that metastasized to brain, heart, and lung lymph nodes benefited from immunotherapy.

Bladder cancer is a common malignant tumor of the genitourinary system, with the primary cause of death being metastasis. The most common metastatic sites are the lymph nodes, liver, lung, bone, peritoneum, pleura, kidney, adrenal gland, and the intestine. Brain and heart metastases are rare. In this report, we describe a patient who had pulmonary lymph node metastases more than a year after being diagnosed with bladder cancer, followed by brain and cardiac metastases more than two years later. Following the failure of standard first-line chemotherapy, the patient accepted 6 cycles of tislelizumab immunotherapy. The re-examination revealed that the bilateral frontal brain metastases had vanished, the right temporal lobe metastases had been greatly decreased, the neurological symptoms had been alleviated, and the cardiac metastases had disappeared. This is a rare clinical case with encouraging effects of tislelizumab and can serve as a model for the treatment of similar patients.

[Influence of sleep quality on symptoms in children with attention deficit hyperactivity disorder: the mediating role of working memory]. / ç¡çœ è´¨é‡å¯¹æ³¨æ„ç¼ºé™·å¤šåŠ¨éšœç¢å„¿ç«¥ç—‡çŠ¶çš„å½±å“ï¼šå·¥ä½œè®°å¿†çš„ä¸­ä»‹ä½œç”¨.

OBJECTIVES: To study the mediating role of working memory between sleep quality and symptoms in children with attention deficit hyperactivity disorder (ADHD). METHODS: The cluster random sampling method was used to select 110 ADHD children and 124 normal children as subjects from grade 3-5 students in two primary schools in Kashgar, Xinjiang Uygur Autonomous Region, China. SNAP-IV, Pittsburgh Sleep Quality Index (PSQI), and visual-spatial working memory paradigm were used for investigation and comparison. RESULTS: Compared with the normal group, the ADHD group had a significantly higher total score of PSQI and scores of subjective sleep quality, sleep latency, sleep efficiency, sleep disturbance, and a higher incidence of sleep quality problems (P<0.001). The working memory score in the ADHD group was significantly lower than that in the normal group (P<0.001). In the ADHD group, the working memory score was negatively correlated with the total score of PSQI (rs=-0.271, P<0.001) and the score of symptoms (rs=-0.439, P<0.001), and the total score of PSQI was positively correlated with the score of symptoms (rs=0.540, P<0.001). Working memory had a partial mediating effect in the influence of sleep quality on symptoms in children with ADHD, accounting for 18.10% of the total effect. CONCLUSIONS: Sleep quality issues are observed in some children with ADHD, and working memory plays a mediating role between sleep quality and symptoms in ADHD children.

Greenness may improve lung health in low-moderate but not high air pollution areas: Seven Northeastern Cities' study.

INTRODUCTION: There is growing interest in the impact of greenness exposure on airway diseases, but the impact of greenness on lung function in children is limited. We aimed to investigate the associations between greenness surrounding schools and lung function in children and whether these associations are modified by air pollution exposure. METHODS: Between 2012 and 2013, a cross-sectional survey and spirometry were performed among 6740 school children. Lung function patterns were determined as obstructive forced expiratory volume 1 s/forced vital capacity (FEV1/FVC <0.8) or restrictive (FEV1/FVC ≥0.8 but FVC <80% of predicted). School greenness was defined by Normalized difference vegetation index (NDVI) and soil-adjusted vegetation index. Nitrogen dioxide, sulphur dioxide and particular matter concentrations were assessed using a spatiotemporal model and national monitoring data. Two-level generalised linear models were used to investigate associations and interactions. RESULTS: Overall, an IQR in NDVI within 500 m was associated with higher FEV1 (+57 mL 95% CI 44 to 70) and FVC (+58 mL 95% CI 43 to 73). NDVI was similarly associated with 25% reduced odds of spirometric restriction (OR: 0.75, 95% CI 0.65 to 0.86). However, among children exposed to the highest compared with the lowest quartile of particulate matter, increasing NDVI was paradoxically associated with lower -40 mL FVC (95% CI -47 to -33, p interaction <0.05). DISCUSSION: Our findings suggest that, in this study population, greening urban areas may promote lung health in low-moderate pollution areas but not in high air pollution areas. If the findings are replicated in other moderate-to-high pollution settings, this highlights a need to have a flexible green policy.

Microenvironment-Sensitive Fluorescent Ligand Binds Ascaris Telomere Antiparallel G-Quadruplex DNA with Blue-Shift and Enhanced Emission.

The development of small molecules that can selectively target G-quadruplex (G4) DNAs has drawn considerable attention due to their unique physiological and pathological functions. However, only a few molecules have been found to selectively bind a particular G4 DNA structure. We have developed a fluorescence ligand Q1, a molecular scaffold with a carbazole-pyridine core bridged by a phenylboronic acid side chain, that acts as a selective ascaris telomere antiparallel G4 DNA ASC20 ligand with about 18 nm blue-shifted and enhanced fluorescence intensity. Photophysical properties revealed that Q1 was sensitive to the microenvironment and gave the best selectivity to ASC20 with an equilibrium binding constant Ka =6.04×105  M-1 . Time-resolved fluorescence studies also demonstrated that Q1 showed a longer fluorescence lifetime in the presence of ASC20. The binding characteristics of Q1 with ASC20 were shown in detail in a fluorescent intercalator displacement (FID) assay, a 2-Ap titration experiment and by molecular docking. Ligand Q1 could adopt an appropriate pose at terminal G-quartets of ASC20 through multiple interactions including π-π stacking between aromatic rings; this led to strong fluorescence enhancement. In addition, a co-staining image showed that Q1 is mainly distributed in the cytoplasm. Accordingly, this work provides insights for the development of ligands that selectively targeting a specific G4 DNA structure.

Design, synthesis and mechanistic studies of a TICT based fluorogenic probe for lighting up protein HSA.

Human serum albumin (HSA) in blood serves as an important biomarker for clinical diagnosis, and fluorescence sensing method has attracted extensive attention. In this work, a small organic molecule probe, YS8, involving twisted intramolecular charge transfer (TICT) characteristic, was designed and investigated to detect HSA. YS8 kept silent state in fluorescence under physiological conditions, but the encapsulation of YS8 in the hydrophobic subdomain IB region of HSA inhibited the TICT state and produced a clear light-up fluorescent signal. Especially, YS8 was demonstrated to be an efficient fluorogenic probe to discriminate HSA from other proteins including the bovine serum albumin (BSA). Moreover, YS8/HSA complex could be applied in fluorescence imaging in living cells and is also useful in the study of artificial fluorescent protein (AFP).

Short-Term Effects of Particle Sizes and Constituents on Blood Biomarkers among Healthy Young Adults in Guangzhou, China.

Evidence of the effects of various particle sizes and constituents on blood biomarkers is limited. We performed a panel study with five repeated measurements in 88 healthy college students in Guangzhou, China between December 2017 and January 2018. Mass concentrations of particles with aerodynamic diameters ≤ 2.5 µm (PM2.5), PM1, and PM0.5 and number concentrations of particles with aerodynamic diameters ≤ 200 nm (PN0.2) and PN0.1 were measured. We used linear mixed-effect models to explore the associations of size-fractionated particulate matter and PM2.5 constituents with five blood biomarkers 0-5 days prior to blood collection. We found that an interquartile range (45.9 µg/m3) increase in PM2.5 concentration was significantly associated with increments of 16.6, 3.4, 12.3, and 8.8% in C-reactive protein (CRP), monocyte chemoattractant protein-1 (MCP-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), and endothelin-1(ET-1) at a 5-day lag, respectively. Similar estimates were observed for PM1, PM0.5, PN0.2, and PN0.1. For PM2.5 constituents, consistent positive associations were observed between F- and sVCAM-1 and CRP and between NH4+ and MCP-1, and negative associations were found between Na+ and MCP-1 and ET-1, between Cl- and MCP-1, and between Mg2+ and sVCAM-1. Our results suggested that both particle size and constituent exposure are significantly associated with circulating biomarkers among healthy Chinese adults. Particularly, PN0.1 at a 5-day lag and F- and NH4+ are the most associated with these blood biomarkers.

The high power conversion efficiency of a two-dimensional GeSe/AsP van der Waals heterostructure for solar energy cells.

Constructing a van der Waals heterostructure is a practical way to promote the conversion efficiency of solar energy. Here, we demonstrate the efficient performance of a GeSe/AsP heterostructure in solar energy cells based on the first-principles calculations. The electronic properties, optical absorption, and optoelectronic properties are calculated to evaluate the efficiency of the newly designed heterostructure. The results indicate that the GeSe/AsP heterostructure possesses a type-II band alignment with an indirect bandgap of 1.10 eV, which greatly promotes the effective separation of photogenerated carriers. Besides, an intrinsic electric field is formed in the direction from the AsP to GeSe monolayer, which is beneficial to prevent the recombination of the photogenerated electron-hole pair. Simultaneously, a strong optical absorption is observed in the visible light range. The predicted power conversion efficiency (PCE) of the GeSe/AsP heterostructure is 16.0% and can be promoted to 17.3% by applying 1% biaxial compression strain. The present results indicate that the GeSe/AsP heterostructure is a promising candidate material for high-performance solar cells.

Exposure to second-hand smoke during early life and subsequent sleep problems in children: a population-based cross-sectional study.

BACKGROUND: Previous studies have revealed that current secondhand smoke exposure showed highly suggestive evidence for increased risk of simultaneous sleep problems in children. Data on the associations between early-life exposure to SHS with subsequent sleep problems in children were scarce. We aimed to evaluate the associations of early-life SHS exposure with sleep problems in children. METHODS: In this cross-sectional study, children were recruited from elementary and middle schools in Liaoning Province, China between April 2012 and January 2013. We assessed early-life SHS exposure (pregnancy and the first 2 years of life) via questionnaires. Sleep problems and different types of sleep-related symptoms were measured based on the validated tool of the Sleep Disturbance Scale for Children (SDSC). Generalized linear mixed models were applied to estimate the associations of early-life SHS exposure with sleep problems. RESULTS: We included a total of 45,562 children (22,657 [49.7%] males; mean [SD] age, 11.0 [2.6] years) and 6167 of them (13.5%) were exposed to early-life SHS during both pregnancy and the first 2 years of life. Compared with unexposed counterparts, children exposed to early-life SHS had higher total T-scores of SDSC (ß = 4.32; 95%CI: 4.06, 4.58) and higher odds of increased sleep problems (OR = 2.14; 95%CI: 1.89, 2.42). When considering different sleep-related symptoms, the associations between early-life SHS exposure and symptom of sleep-wake transition disorders (i.e., bruxism) were the strongest in all analyses. CONCLUSIONS: Early-life SHS exposure was associated with higher odds of global sleep problems and different sleep-related symptoms in children aged 6-18 years. Our findings highlight the importance to strengthen efforts to support the critical importance of maintaining a smoke-free environment especially in early life.

Splenic Artery Pseudoaneurysm in Chronic Pancreatitis Causing Obstructive Jaundice: Endovascular Management.

BACKGROUND: Splenic artery pseudoaneurysm (SAP) around the pancreatic head causing obstructive jaundice is an extremely rare complication but can be life threatening once occurs. This case report is to raise awareness of this catastrophic complication and share our experience of successful endovascular management. METHODS: A 47-year-old male with a history of chronic pancreatitis clinically presented with epigastric pain and jaundice. Proximal SAP complicated with obstructive jaundice was confirmed by laboratory and imaging investigations. The SAP was successfully treated by transarterial coil embolization, and the jaundice subsequently improved. RESULTS: Abdominal contrast-enhanced computed tomography 11 months after embolization showed complete occlusion and reduction in the volume of the SAP as well as normal biliary tract. CONCLUSIONS: SAP complicated with obstructive jaundice should be managed timeously and aggressively once diagnosed, given its potential adverse consequences. Transarterial embolization using the isolation technique may be a safe and effective strategy for treating this disease.

Endovascular Management of Isolated Superior Mesenteric Artery Dissecting Aneurysm by Retrograde Catheterization Via Collaterals from the Celiac Artery.

Isolated superior mesenteric artery (SMA) dissecting aneurysm is frequently symptomatic and potentially catastrophic; thus, it usually requires endovascular treatment. The endovascular management can be challenging in certain cases as catheterization of the collapsed true lumen is often very difficult. This case report is to describe a new approach for catheterization of the true lumen of the SMA in a case of isolated SMA dissecting aneurysm. A 63-year-old male with an SMA dissecting aneurysm underwent stent-graft placement for treatment. Catheterization of the true lumen via the anterograde approach was unsuccessful because of angulation and collapse of the SMA true lumen as a result of the dissecting aneurysm. A guidewire was passed through the collaterals from the celiac artery and retrogradely passed across the collapsed SMA true lumen into the aorta. We then used a snare that had been delivered through the contralateral femoral access to capture and retrieve the guidewire. A delivery system was advanced into the SMA, and a stent graft was successfully deployed to occlude the dissecting aneurysm. This report introduces a new feasible retrograde approach that provides access to the SMA true lumen via celiac collaterals in cases of difficult antegrade catheterization of an SMA dissecting aneurysm.

Integrative genomic analyses identify WDR12 as a novel oncogene involved in glioblastoma.

Glioblastoma (GBM) is the most malignant primary brain tumor in adults. Due to its invasive nature, it cannot be thoroughly eliminated. WD repeat domain 12 (WDR12) processes the 32S precursor rRNA but cannot affect the synthesis of the 45S/47S primary transcript. In this study, we found that WDR12 is highly expressed in GBM according to the analysis results of mRNA expression by The Cancer Genome Atlas database. The high expression level of WDR12 is dramatically related to shorter overall survival and reduced disease-free survival. Next, we knocked down WDR12 and found that knockdown of WDR12 promoted the apoptosis and inhibited the proliferation by cell biology experiments. Differential expression genes in gene-chip revealed that WDR12 knockdown mainly inhibited cell cycle. Finally, we also found that WDR12 is associated with PLK1 and EZH2 in cell proliferation of GBM. Resumptively, this report showed a possible evidence that WDR12 drove malignant behavior of GBM, whose expression may present a neoteric independent prognostic biomarker in GBM.

POU4F1 confers trastuzumab resistance in HER2-positive breast cancer through regulating ERK1/2 signaling pathway.

Over-expression of the human epidermal growth factor receptor-2 (HER2) is related to aggressive tumors and poor prognosis in breast cancer. Trastuzumab (TRA) resistance leads to tumor recurrence and metastasis, resulting in poor prognosis in HER2-positive breast cancer. POU Class 4 Homeobox 1 (POU4F1) is a member of the POU domain family transcription factors, and has a key role in regulating cancers. However, its effects on TRA-resistant HER2-positive breast cancer are still vague. In the present study, we found that POU4F1 expression was dramatically increased in clinical breast cancer specimens with TRA resistance. Higher POU4F1 was also detected in HER2-positive breast cancer cells with TRA resistance than that of the parental ones. Poor prognosis was detected in breast cancer patients with high POU4F1 expression. Under TRA treatment, POU4F1 knockdown significantly reduced the proliferative capacity of HER2-positive breast cancer cells with TRA resistance. POU4F1 silence also sensitized resistant HER-positive breast cancer cells to TRA treatment in vivo using a xenograft mouse model, along with the markedly reduced tumor growth rate and tumor weight. Moreover, we found that POU4F1 deletion greatly decreased the activation of mitogen-activated or extracellular signal-regulated protein kinase kinases 1 and 2 (MEK1/2) and extracellular-regulated kinase 1/2 (ERK1/2) signaling pathways in breast cancer cells with TRA resistance. Migration and invasion were also effectively hindered by POU4F1 knockdown in TRA-resistant HER2-positive breast cancer cells. Notably, we found that POU4F1 deletion-improved chemosensitivity of HER2-positive breast cancer cells with drug-resistance to TRA treatment was closely associated with the blockage of ERK1/2 signaling. Collectively, our findings reported a critical role of POU4F1 in regulating TRA resistance, and demonstrated the underlying molecular mechanisms in HER2-positive breast cancer. Thus, POU4F1 may be a promising prognostic and therapeutic target to develop effective treatment for overcoming TRA resistance.

Onboard absolute radiometric calibration and validation of the satellite calibration spectrometer on HY-1C.

As the reference radiometric calibration standard of sensors on the Haiyang-1C (HY-1C) satellite platform, the satellite calibration spectrometer (SCS) is equipped with an onboard calibration system composed of double solar diffusers and an erbium-doped diffuser to monitor the postlaunch radiometric response change. Herein, through onboard calibration data analysis, the calibration diffuser performance remains stable without degradation, and the Moderate Resolution Imaging Spectroradiometer (MODIS) on Terra is adopted as a reference to repeatedly verify onboard radiometric calibration results by selecting different dates and reflectance scenes. The SCS equivalent reflectance is obtained by combining the mean digital number (DN) of the SCS crossing area image with the radiometric calibration coefficient. The spectral reflectance is obtained via interpolation and iteration, which is adopted as the actual MODIS incident pupil spectral reflectance because the small imaging time interval can be ignored and almost vertically observed, and it is convoluted with the MODIS spectral response function to obtain the predicted equivalent reflectance. Validation is completed by comparing the predicted MODIS equivalent reflectance to the measured value based on the onboard calibration coefficient. The results show that (1) the difference between the measured and predicted MODIS band equivalent reflectance is between -0.00466 and 0.0039, and (2) the percentage difference between the measured and predicted MODIS band equivalent reflectance ranges from 4.17% and 1.24%, indicating that the calibration system carried on HY-1C can perform high-precision SCS radiometric calibration, meeting the cross-calibration accuracy requirements of other loads on the same platform.

A fluorescent supramolecular gel and its application in the ultrasensitive detection of CN- by anion-π interactions.

Supramolecular gels have been widely reported on account of their unique superiority and application prospects. In this work, we constructed a novel supramolecular gel (HD-G) by using hydroxy-naphthaldehyde decorated with naphthalimide in DMSO solution, which exhibited excellent selectivity and ultrasensitive sensing properties toward CN- (the lowest detection limit is 1.82 × 10-10 M). The sensing mechanism of this supramolecular gel takes advantage of π-π stacking interactions and anion-π interactions, which is different from the other familiar methods.