Non-KREEP origin for Chang'e-5 basalts in the Procellarum KREEP Terrane.

Mare volcanics on the Moon are the key record of thermo-chemical evolution throughout most of lunar history1-3. Young mare basalts-mainly distributed in a region rich in potassium, rare-earth elements and phosphorus (KREEP) in Oceanus Procellarum, called the Procellarum KREEP Terrane (PKT)4-were thought to be formed from KREEP-rich sources at depth5-7. However, this hypothesis has not been tested with young basalts from the PKT. Here we present a petrological and geochemical study of the basalt clasts from the PKT returned by the Chang'e-5 mission8. These two-billion-year-old basalts are the youngest lunar samples reported so far9. Bulk rock compositions have moderate titanium and high iron contents  with KREEP-like rare-earth-element and high thorium concentrations. However, strontium-neodymium isotopes indicate that these basalts were derived from a non-KREEP mantle source. To produce the high abundances of rare-earth elements and thorium, low-degree partial melting and extensive fractional crystallization are required. Our results indicate that the KREEP association may not be a prerequisite for young mare volcanism. Absolving the need to invoke heat-producing elements in their source implies a more sustained cooling history of the lunar interior to generate the Moon's youngest melts.

Event-Triggered Distributed Fusion Estimator for Asynchronous Markov Jump Systems with Correlated Noises and Fading Measurements.

In this study, we investigate event-triggered distributed fusion estimation for asynchronous Markov jump systems subject to correlated noises and fading measurements. The measurement noises are interrelated, and they are simultaneously coupled with the system noise. The sensor samples measurements uniformly, and the sampling rates of the sensors are different. First, the asynchronous system is synchronized at state update points; then, the local filter is obtained. Furthermore, a variance-based event-triggered strategy is introduced between the local estimator and the fusion center to decrease the energy consumption of network communication. Then, a distributed fusion estimation algorithm is proposed using a matrix-weighted fusion criterion. Finally, the effectiveness of the algorithm is verified using computer simulations.

TGF-ß1 mediates tumor immunosuppression aggravating at the late stage post-high-light-dose photodynamic therapy.

Photodynamic therapy (PDT) is an emerging clinical treatment that is expected to become an important adjuvant strategy for the immunotherapeutic cancer treatment. Recently, numerous works have reported combination strategies. However, clinical data showed that the anti-tumor immune response of PDT was not lasting though existing. The immune activation effect will eventually turn to immunosuppressive effect and get aggravated at the late stage post-PDT. So far, the mechanism is still unclear, which limits the design of specific correction strategies and further development of PDT. Several lines of evidence suggest a role for TGF-ß1 in the immunosuppression associated with PDT. Herein, this study systematically illustrated the dynamic changes of immune states post-PDT within the tumor microenvironment. The results clearly demonstrated that high-light-dose PDT, as a therapeutic dose, induced early immune activation followed by late immunosuppression, which was mediated by the activated TGF-ß1 upregulation. Then, the mechanism of PDT-induced TGF-ß1 accumulation and immunosuppression was elucidated, including the ROS/TGF-ß1/MMP-9 positive feedback loop and CD44-mediated local amplification, which was further confirmed by spatial transcriptomics, as well as by the extensive immune inhibitory effect of local high concentration of TGF-ß1. Finally, a TGF-ß blockade treatment strategy was presented as a promising combinational strategy to reverse high-light-dose PDT-associated immunosuppression. The results of this study provide new insights for the biology mechanism and smart improvement approaches to enhance tumor photodynamic immunotherapy.

Comparison of the performance of various virtual articulator mounting procedures: a self-controlled clinical study.

OBJECTIVES: This clinical study aimed to compare the performance of various virtual articulator (VA) mounting procedures in the participants' natural head position (NHP). MATERIALS AND METHODS: Fourteen participants with acceptable dentitions and jaw relationships were recruited in this study registered in the Clinical Trials Registry (#NCT05512455; August 2022). A virtual facebow was designed for virtual mounting and hinge axis measurement. Intraoral scans were obtained, and landmarks were placed on each participant's face to register the horizontal plane in NHP. Six virtual mounting procedures were performed for each participant. The average facebow group (AFG) used an indirect digital procedure by using the average facebow record. The average mounting group (AMG) aligned virtual arch models to VA's average occlusal plane. The smartphone facial scan group (SFG) and professional facial scan group (PFG) used facial scan images with Beyron points and horizontal landmarks, respectively. The cone-beam computed tomography (CBCT) scan group (CTG) used the condyle medial pole, and horizontal landmarks were applied. The kinematic facebow group (KFG) served as the control group, and a direct digital procedure was applied using a kinematic digital facebow and the 3D skull model. Deviations of the reference plane and the hinge axis between the KFG and other groups were calculated. The inter-observer variability in virtual mounting software operation was then evaluated using the interclass correlation coefficient (ICC) test. RESULTS: In virtual condylar center deviations, the CTG had the lowest condylar deviations. The AFG showed larger condylar deviations than PFG, SFG, and CTG. There was no statistically significant difference between the AFG and the AMG and between the PFG and the SFG. In reference plane deviations, the AMG showed the largest angular deviation (8.23 ± 3.29°), and the AFG was 3.89 ± 2.25°. The angular deviations of PFG, SFG, and CTG were very small (means of each group < 1.00°), and there was no significant difference among them. There was no significant difference between the researchers, and the ICC test showed moderate to excellent reliability for the virtual condylar center and good to excellent reliability for the reference plane in the operation of the virtual mounting software. CONCLUSIONS: CBCT scan provided the lowest hinge axis deviation in virtual mounting compared to average mounting, facebow record, and facial scans. The performance of the smartphone facial scanner in virtual mounting was similar to that of the professional facial scanner. Direct virtual mounting procedures using horizontal landmarks in NHP accurately recorded the horizontal plane. CLINICAL RELEVANCE: Direct digital procedures can be reliably used for virtual articulator mounting. The use of a smartphone facial scanner provides a suitable and radiation-free option for clinicians.

Comparison of occlusal contact errors of 6 chairside CAD/CAM crowns: a self-controlled clinical study.

OBJECTIVES: The purpose of this self-controlled clinical study was to evaluate the trueness of occlusal contacts of chairside CAD/CAM crowns fabricated using different ceramic materials. MATERIALS AND METHODS: Ten volunteers (8 females, 2 males, average aged 20-30) were recruited in this study registered in the Clinical Trials Registry (#NCT05346744). After tooth preparation on tooth 36 or 46, an optical scan unit (CEREC Omnicam, Sirona Dental Systems, Germany) was utilized to perform the intraoral scanning. For each volunteer, 6 crowns were fabricated via the chairside CAD/CAM process (CEREC, Sirona Dental Systems, Germany) using the following materials: InCoris TZI (ZIR), Celtra Duo (CD), e.max CAD (EMA), UP.CAD (UP), Enamic (ENA) and Hyramic (HY). The microhardness of the milled surfaces was measured through a Vickers hardness Tester (HVS-50Z, Trojan, China). Together with the amount of occlusal adjustment, the occlusal contact trueness at both milling and postprocessing stages were quantitatively analyzed by using a high-precision scanner (ATOS, GOM Technologies, USA) and a reverse engineering software (Geomagic Control, 3D Systems, Rock Hill, SC). The times of chairside occlusal adjustment were also recorded. Data were analyzed by one-way analysis of variance (ANOVA) and ANOVA with randomized block design followed by Bonferroni test (p = 0.05). RESULTS: Significant differences were found in surface microhardness of the materials tested (CD > EMA ~ UP > ENA > HY > ZIR, p < 0.05). Regarding the occlusal contact trueness at milling stage, ZIR showed the lowest (p < 0.05), while no significant difference was found among others (p > 0.05). At postprocessing stage, except for ENA, the occlusal contact trueness of ZIR was significantly lower than that of others (p < 0.05). As for occlusal adjustment amount, ZIR was lower than CD and ENA (p < 0.05). In addition, ENA, HY and ZIR required fewer times of occlusal adjustment than EMA, UP and CD. CONCLUSIONS: The type of chairside CAD/CAM ceramic materials affected the occlusal contact trueness throughout the process of manufacturing and the amount of clinical occlusal adjustment as well. Zirconia exhibited the worst occlusal contact trueness at both milling and postprocessing stages, while the amount of occlusal adjustment was the least, which recommended the least occlusal compensation. CLINICAL RELEVANCE: For better trueness, different negative occlusal offsets are suggested to be applied in the design process, so as to suit the material of the restoration.

Comparative analysis of leaching residual monomer and biological effects of four types of conventional and CAD/CAM dental polymers: an in vitro study.

OBJECTIVES: The objective of this study is to investigate leaching residual monomer and biological effects of four types of conventional and computer-aided design/computer-aided manufacturing (CAD/CAM) dental polymers on human gingival fibroblasts (HGFs). MATERIALS AND METHODS: A total of 540 disk-shaped specimens were fabricated from four different materials (n=135 per group): compression-molding polymethylmethacrylate (PMMA) (conventional denture polymer), CAD/CAM PMMA (CAD/CAM denture polymer), bis-acrylic composite resin (conventional temporary polymer), and CAD/CAM PMMA (CAD/CAM temporary polymer). Specimens were eluted in cell culture medium for 72 h at 37°C, and the residual monomer in eluates subsequently was measured by high-performance liquid chromatography (HPLC). The biological effects of material eluates on HGFs were analyzed by CCK-8 assay, flow cytometry, real-time quantitative PCR, Western blotting, and enzyme-linked immunosorbent assay (ELISA) to identify cell death patterns and its biological mechanism. RESULTS: Methyl methacrylate (MMA) was detected only in compression-molding PMMA, and by-products were detected in bis-acrylic composite resin. The cell proliferation of CAD/CAM denture polymer or CAD/CAM temporary polymer was greater than that of compression-molding PMMA or bis-acrylic composite resin at 72 h in culture. No apoptosis and necrosis were detected in CAD/CAM dental polymers. Apoptosis was detected only in bis-acrylic composite resin and further confirmed by the upregulation of Bax and cleaved Caspase-3, as well as the downregulation of Bcl-2 gene. And no significant variation in inflammatory cytokines secretion was observed in all materials. CONCLUSIONS: CAD/CAM dental polymers (including temporary and denture polymers) have favorable biocompatibility due to lower residual monomer, which provides scientific evidence to the controversy of biocompatibility of conventional and CAD/CAM dental polymers. CLINICAL RELEVANCE: The use of CAD/CAM dental polymers is recommended in the fabrication of temporary restorations and dentures due to their favorable biocompatibility.

In vitro study of surface properties and microbial adhesion of various dental polymers fabricated by different manufacturing techniques after thermocycling.

OBJECTIVES: The study aims to investigate surface properties and microbial adhesion of various dental polymers fabricated by different manufacturing techniques before and after thermocycling. MATERIALS AND METHODS: The following six materials were used to fabricate disk-shaped specimens: conventional denture polymer (Vertex Acrylic Resin, VAR), CAD/CAM denture polymer (Organic PMMA eco Pink, OP), conventional temporary polymer (Protemp™ 4, PT), CAD/CAM temporary polymer (Die Material, DM), conventional denture framework polymer (BioHPP, PB), and CAD/CAM denture framework polymer (breCAM.BioHPP, CB). The specimens were tested before and after thermocycling (5000 and 10,000 cycles, 5 °C/55 °C). Surface roughness (SR), hydrophobicity, and surface topography were determined by profilometry, water contact angle, and scanning electron microscopy (SEM). Then specimens were incubated with Staphylococcus aureus, Streptococcus mutans, and Candida albicans for 24 h, respectively. Microbial adhesion was assessed using colony-forming unit counts, XTT assay, and SEM. RESULTS: SR and hydrophobicity of VAR group were higher than that of OP group. S. aureus and C. albicans adhesion on VAR and PT groups were higher than that on OP and DM groups, respectively. There was no difference in surface properties and microbial adhesion between PB and CB groups. After thermocycling, SR (expect OP group) of all materials increased and hydrophobicity decreased, and the amount and activity of S. aureus and C. albicans adhesion also increased. The adhesion of S. aureus and C. albicans showed a moderate positive correlation with SR, independent of hydrophobicity. CONCLUSIONS: CAD/CAM denture polymers and temporary polymers showed less S. aureus and C. albicans adhesion when compared to conventional ones, which were mainly affected by surface roughness, independent of hydrophobicity. Thermocycling could increase surface roughness, decrease hydrophobicity, and affect microbial adhesion of the materials. CLINICAL SIGNIFICANCE: CAD/CAM dental polymers may be a better choice for the manufacture of temporary restorations and dentures to reduce microbial adhesion.

State Estimation for a Class of Non-Uniform Sampling Systems with Missing Measurements.

This paper is concerned with the state estimation problem for a class of non-uniform sampling systems with missing measurements where the state is updated uniformly and the measurements are sampled randomly. A new state model is developed to depict the dynamics at the measurement sampling points within a state update period. A non-augmented state estimator dependent on the missing rate is presented by applying an innovation analysis approach. It can provide the state estimates at the state update points and at the measurement sampling points within a state update period. Compared with the augmented method, the proposed algorithm can reduce the computational burden with the increase of the number of measurement samples within a state update period. It can deal with the optimal estimation problem for single and multi-sensor systems in a unified way. To improve the reliability, a distributed suboptimal fusion estimator at the state update points is also given for multi-sensor systems by using the covariance intersection fusion algorithm. The simulation research verifies the effectiveness of the proposed algorithms.

[Study on Recognition Model of Phyllosilicate of Martian Surface].

Phyllosilicate belongs to hydrated silica, which is a principal form of hydrous minerals on the martian surface. It's also an indicator in comparing different sediments and degree of aqueous alteration. Therefore, it's essential to establish its recognition model for studying the geologic evolution of the Mars. Short-wave infrared (SWIR) spectral bands and thermal infrared (TIR) spectral bands have distinct spectral response to the mineral groups and ions, so they have distinctive advantages in detecting minerals. However the method of combining SWIR and TIR to recognize phyllosilicate is rarely studied. Based on the USGS spectral library, facing Compact Reconnaissance Imaging Spectrometer for Mars(CRISM) and Thermal Emission Imaging System(THEMIS),we conducted the research on the mechanism of the spectral response of phyllosilicate, and established the SWIR and TIR identification model respectively, then combined the SWIR and TIR spectral features to build the combined recognition model of phyllosilicate with Fisher discriminant analysis. The results of cross validation show that the identification accuracy of combined model is the highest, which can correctly classify 90.6% of the mineral samples and improve the identification precision of phyllosilicate effectively.

Geological context of the Chang'e-6 landing area and implications for sample analysis.

Research on returned samples can provide ground truth for the study of the geological evolution history of the Moon. However, previous missions all collected samples from the near side of the Moon, which is significantly different from the far side of the Moon in terms of the thickness of the lunar crust, magma activity, and composition. Therefore, the samples from the far side of the Moon are of great significance for a comprehensive understanding of the history of the Moon. China's Chang'e-6 (CE-6) probe has successfully landed on the lunar far side and will return samples in the coming days. With the precise location of the CE-6 landing site, a detailed analysis of the geological background is conducted in this research. The landing site of CE-6 is within the Apollo crater, which is inside the largest impact basin on the Moon, i.e., the South Pole-Aitken (SPA) basin. According to the numerical simulation of the formation process of the SPA basin, CE-6 landed at the edge of the SPA impact melting zone, which is presumably composed of impact melt of the lunar mantle. The Apollo crater subsequently excavated deep material again, which constitutes the basement of the CE-6 landing area. Later, erupted basalt covered these basement rocks, and they also constitute the main source of the CE-6 samples. Based on the dating method of crater size-frequency distribution, we find that the basalt is ∼2.50 Ga. The CE-6 samples also possibly contain basement rocks as excavated and ejected by craters, and they can provide crucial information for our understanding of lunar geological history along with the basalt samples.

Higher water content observed in smaller size fraction of Chang'e-5 lunar regolith samples.

Water has been detected in lunar regolith, with multiple sources identified through the analysis of individual grains. However, the primary origin of water in the bulk lunar regolith remains uncertain. This study presents spectroscopic analyses of water content in sealed Chang'e-5 samples. These samples were sieved into various size fractions (bulk, <45 µm, and 45-355 µm) inside a glovebox filled with high-purity nitrogen. Results indicate a higher water content in the fine fractions (∼87 ± 11.9 ppm) than in bulk soil (∼37 ± 4.8 ppm) and coarse fractions (∼11 ± 1.5 ppm). This suggests that water is predominantly concentrated in the outermost rims of the regolith grains, and thus exhibits dependence on the surface volume ratio (also known as surface correlation), indicating solar wind is a primary source of lunar surface water. Laboratory, in-situ, and orbital results bridge sample analysis and remote sensing, offering a cohesive understanding of lunar surface water characteristics as represented by Chang'e-5. The discovery provides statistical evidence for the origin of water in lunar soil and can be considered representative of the lunar surface conditions. The water enrichment of the finest fraction suggests the feasibility of employing size sorting of lunar soils as a potential technological approach for water resource extraction in future lunar research stations.

Return to the Moon: New perspectives on lunar exploration.

Lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity's exploration of deep space. Over the past decade, the Chinese Lunar Exploration Program (CLEP), also known as the Chang'e (CE) Project, has achieved remarkable milestones. It has successfully developed and demonstrated the engineering capability required to reach and return from the lunar surface. Notably, the CE Project has made historic firsts with the landing and on-site exploration of the far side of the Moon, along with the collection of the youngest volcanic samples from the Procellarum KREEP Terrane. These achievements have significantly enhanced our understanding of lunar evolution. Building on this success, China has proposed an ambitious crewed lunar exploration strategy, aiming to return to the Moon for scientific exploration and utilization. This plan encompasses two primary phases: the first crewed lunar landing and exploration, followed by a thousand-kilometer scale scientific expedition to construct a geological cross-section across the lunar surface. Recognizing the limitations of current lunar exploration efforts and China's engineering and technical capabilities, this paper explores the benefits of crewed lunar exploration while leveraging synergies with robotic exploration. The study refines fundamental lunar scientific questions that could lead to significant breakthroughs, considering the respective engineering and technological requirements. This research lays a crucial foundation for defining the objectives of future lunar exploration, emphasizing the importance of crewed missions and offering insights into potential advancements in lunar science.

Treatment of multiple ceramic alloys before recasting.

STATEMENT OF PROBLEM: Dental laboratories often reuse dental casting alloys by recasting them, but the processing methods before recasting require further research. PURPOSE: The purpose of the study was to determine the treatment methods to remove the surface contamination of the previously melted alloys before recasting. MATERIAL AND METHODS: Cobalt-chromium (Co-Cr), commercially pure titanium (CP Ti), palladium-copper-gallium (Pd-Cu-Ga), and gold-platinum (Au-Pt) ceramic alloys were investigated in the present study. Field emission scanning electron microscopy, energy-dispersive x-ray spectroscopy (EDAX), and x-ray photoelectron spectroscopy (XPS) were used to evaluate the changes in the surface structures and compositions of Co-Cr, CP Ti, Pd-Cu-Ga, and Au-Pt ceramic alloys after airborne-particle abrasion and immersion in various chemical solutions for different time periods. The data obtained by EDAX and XPS were statistically analyzed by Kruskal-Wallis and Nemenyi tests (α=.05). RESULTS: By using appropriate mechanical and chemical treatment procedures, the contamination content of previously cast ceramic alloys was found to be below the detection limits of EDAX and XPS. The statistical results showed that, compared to the control group (new alloys after polishing), the impurity element was not detected after being treated with these methods, which was not statistically different to control group. CONCLUSIONS: The surface contamination of ceramic alloys was effectively removed by using certain mechanical and/or chemical treatment methods. Within the limitations of the present study, the most appropriate ways to treat ceramic alloys before recasting were as follows: (1) for Co-Cr ceramic alloys: Al2O3 airborne-particle abrasion and immersion in aqua regia for 15 min; (2) for CP Ti ceramic alloys: Al2O3 airborne-particle abrasion and immersion in 65% HNO3 and 40% HF 1:7 (V/V) for 60 min; (3) for Pd-Cu-Ga ceramic alloys: glass bead airborne-particle abrasion and immersion in 40% HF solution for 30 min; and (4) for Au-Pt ceramic alloys: glass bead airborne-particle abrasion.

Intranasally administered thermosensitive gel for brain-targeted delivery of rhynchophylline to treat Parkinson's disease.

The aim of this study is to overcome the obstacle of the blood-brain barrier (BBB) in therapeutic drugs of Parkinson's disease (PD), like rhynchophylline (RIN) entry by intranasal administration and to solve the problem of short residence time of drugs in the nasal cavity by the dosage form design of thermosensitive gel. We first conducted a study of the screening of absorption enhancers and 3% hydroxypropyl-ß-cyclodextrin (HP-ß-CD) was effective to improve the nasal mucosal permeability of RIN. By adjusting the ratio of different components in order to make the gel with adhesion and rapid gelation which were determined to be Poloxamer 407 (P407) 20%, Poloxamer 188 (P188) 1%, polyethylene glycol 6000 (PEG-6000) 1% and HP-ß-CD 3%. In addition, the characterization showed that the thermosensitive gel was network cross-linked, rapidly gelation upon entry into the nasal cavity and was stable as semi-solid state with adhesion as well as sustained release properties. Moreover, pharmacokinetic study was performed to evaluate the bioavailability and brain targeting of RIN thermosensitive gel and which were 1.6 times and 2.1 times higher than those of oral administration. We also evaluated the anti-PD effects of RIN thermosensitive gel in-vitro as well as in-vivo. The results showed that RIN thermosensitive gel was effective in repairing the motor function impairment, dysregulated expression levels of oxidative stress factors, and positive neuronal damage within the substantia nigra and dopamine caused by PD. The constructed intranasal drug administration strategy through thermosensitive gel provided a new choice for targeted treatment of PD together with other central nervous system diseases.

Influence of fabrication method on the biological properties of modified PEEK.

To investigate the influence of fabrication method on the biological properties of modified PEEK. Two materials were tested in this study: press and CAD/CAM milled ceramic-reinforced PEEK (BioHPP, Bredent, Germany). The residual diphenyl sulfone in these two materials was detected and their biological effects on human gingival fibroblasts (HGFs) were evaluated by assaying cell viability, apoptosis, and inflammation. Diphenyl sulfone was not detected in press and milled BioHPP. The cell viability of them complied with ISO standards. The mRNA expression levels of Bax and Caspase-3 were up-regulated and that of Bcl-2 was downregulated when HGFs were cultured with the eluates of these two materials. There was no difference in cell viability, apoptosis, and inflammation between them. Hence, the fabrication method did not affect the biological properties of modified PEEK, the press and CAD/CAM milled modified PEEK all presented favorable cytocompatibility despite the expression of apoptosis-associated genes at the mRNA level.

In situ analysis of surface composition and meteorology at the Zhurong landing site on Mars.

The Zhurong rover of the Tianwen-1 mission landed in southern Utopia Planitia, providing a unique window into the evolutionary history of the Martian lowlands. During its first 110 sols, Zhurong investigated and categorized surface targets into igneous rocks, lithified duricrusts, cemented duricrusts, soils and sands. The lithified duricrusts, analysed by using laser-induced breakdown spectroscopy onboard Zhurong, show elevated water contents and distinct compositions from those of igneous rocks. The cemented duricrusts are likely formed via water vapor-frost cycling at the atmosphere-soil interface, as supported by the local meteorological conditions. Soils and sands contain elevated magnesium and water, attributed to both hydrated magnesium salts and adsorbed water. The compositional and meteorological evidence indicates potential Amazonian brine activities and present-day water vapor cycling at the soil-atmosphere interface. Searching for further clues to water-related activities and determining the water source by Zhurong are critical to constrain the volatile evolution history at the landing site.

A novel visible light-curing chitosan-based hydrogel membrane for guided tissue regeneration.

Inflammation and trauma destroy the tooth-supporting tissue, leading to the loss of oral function and the difficulty of denture restoration. Guided tissue regeneration (GTR) is a technique based on a barrier membrane designed to restrict soft tissue invasion and maintain the space for bone regeneration. This study examined a new formulation to prepare methacrylated carboxymethyl chitosan (CMCS-MA) hydrogel as a barrier membrane that could be crosslinked under visible-light irradiation. This new CMCS-MA hydrogel showed fast light-curing, good biocompatibility, and could be degraded by lysozyme. Further, the physicochemical property, cytotoxicity and antibacterial activity of the CMCS-MA hydrogels can be adjusted by varying the degree of substitution of methacrylic acid (DS) in a certain range. Thus, the biocompatible and biodegradable CMCS-MA hydrogels may have a promising application in periodontal tissue regeneration with convenience and flexibility.

In situ detection of water on the Moon by the Chang'E-5 lander.

We report analysis results of the reflectance spectra (0.48 to 3.2 µm) acquired by the Chang'E-5 lander, which provides vital context of the returned samples from the Northern Oceanus Procellarum of the Moon. We estimate up to 120 parts per million (ppm) of water (OH + H2O) in the lunar regolith, which is mostly attributed to solar wind implantation. A light-colored and surface-pitted rock (named as CE5-Rock) is evident near the lander. The reflectance spectra suggest that CE5-Rock could be transported from an older basalt unit. CE5-Rock exhibits a stronger absorption, near 2.85 µm, than the surrounding regolith, with estimation of ~180 ppm of water if the model for estimating water content of regolith is applicable to rock samples, which may suggest an additional source from the lunar interior. The low water content of the regolith may suggest the degassing of mantle reservoir beneath the Chang'E-5 landing site.

Minimum Radiant Exposure and Irradiance for Triggering Adequate Polymerization of a Photo-Polymerized Resin Cement.

This study aimed to establish the minimum radiant exposure and irradiance to trigger an adequate polymerization of a photo-polymerized resin cement. In total, 220 disc-shaped specimens (diameter of 10 mm and thickness of 0.1 mm) were fabricated using a photo-polymerized resin cement (Variolink N-transparent, Ivoclar Vivadent). To investigate the minimum radiant exposure, the specimens were polymerized with radiant exposures of 1, 2, 3, 4, 5, 6, and 18 J/cm2 (n = 20). During polymerization, the irradiance was maintained at 200 mW/cm2. To investigate the minimum irradiance, the specimens were polymerized with irradiances of 50, 100, 150, and 200 mW/cm2 (n = 20). During polymerization, the radiant exposure was maintained at the previously determined minimum radiant exposure. The Vickers microhardness (HV) and degree of conversion (DC) of the carbon double bond of the specimens were measured to determine the degree of polymerization of the specimens. The results were analyzed using one-way analysis of variance (ANOVA) and Tukey's test (p < 0.05). In the investigation of the minimum radiant exposure, the HV and DC of the specimens polymerized with a radiant exposure from 1 to 5 J/cm2 were significantly lower than those with 18 J/cm2 (all p < 0.05). However, no significant difference in HV and DC was found between the specimens polymerized with 6 J/cm2 and 18 J/cm2 (p > 0.05). In the investigation of the minimum irradiance, the specimens polymerized with an irradiance of 50 mW/cm2 had significantly lower HV and DC than the specimens polymerized with an irradiance of 200 mW/cm2 (p < 0.05). However, no significant difference in the HV and DC was found among the specimens cured with irradiances of 100, 150, and 200 mW/cm2 (p > 0.05). In conclusion, the minimum radiant exposure and irradiance to trigger an adequate polymerization of the light-cured resin cement were 6 J/cm2 and 100 mW/cm2, respectively.

The apoptotic and autophagic effects of cast Au-Pt, and differently manufactured Co-Cr and cp-Ti on three-dimensional oral mucosal model.

The application of digitally manufactured dental metals has aroused the attention on their biocompatibilities. Three-dimensional oral mucosal model (3D OMM) would provide excellent assessments to the biocompatibility. In the current study, we set to measure metal ion release levels in the extracts of cast gold-platinum alloy (Au-Pt), differently manufactured cobalt-chromium alloy (Co-Cr) and commercially pure titanium (cp-Ti). We further tested two scaffold materials of 3D OMM to determine the better one for the succedent work. Lastly, we evaluated the apoptotic and autophagic effects of cast Au-Pt, and differently manufactured Co-Cr and cp-Ti on mucosal cells based on 3D OMM. We found that, in the construction of 3D OMM, Matrigel showed better performance than bovine acellular dermal matrix. Thus, Matrigel was chosen to construct the 3D OMM in the succedent studies. The results of ion release and biological assessments showed that, firstly, cast Au-Pt and cp-Ti triggered less early apoptotic cells and ion release than cast Co-Cr, implying better chemical stability and biocompatibility of them; secondly, digitally manufactured (including CAD/CAM milling and SLM) Co-Cr showed significantly lower ion release levels and lesser early apoptotic effects on 3D OMM as compared to the cast one. Although cast cp-Ti released much more ions than CAD/CAM milling one, manufacturing methods had no impact on apoptotic effect of cp-Ti. Therefore, we believe that digital methods possess same or even better chemical stability and biocompatibility than conventional casting one. Thirdly, although increased autophagic levels are observed in all test groups, so far there is no evidence that the test metals trigger different levels of autophagy as compared to each other. In addition, correlation analysis indicates that Co, W, and Mn appear to be the potential inducements for the apoptotic and autophagic effects of Co-Cr.