Long-Term Exposure to Outdoor Ultrafine Particles and Black Carbon and Effects on Mortality in Montreal and Toronto, Canada.

INTRODUCTION: Numerous studies support an important relationship between long-term exposure to outdoor fine particulate air pollution (PM2.5) and both nonaccidental and cause-specific mortality. Less is known about the long-term health consequences of other traffic pollutants, including ultrafine particles (UFPs, <0.1 µm) and black carbon (BC), which are often present at elevated concentrations in urban areas but are not currently regulated. Knowledge is lacking largely because these pollutants generally are not monitored by governments and vary greatly over small spatial scales, hindering the evaluation of long-term exposures in population-based studies. METHODS: We aimed to estimate associations between long-term exposures to outdoor UFPs and BC and nonaccidental and cause-specific mortality in Canada's two largest cities, Montreal and Toronto. We considered several approaches to exposure assessment: (1) land use regression (LUR) models based on large-scale year-long mobile monitoring campaigns combined with detailed land use and traffic information; (2) machine learning (i.e., convolutional neural networks [CNN]) models trained by combining mobile monitoring data with aerial images; and (3) the combined use of these two approaches. We also examined exposure models with and without backcasting based on historical trends in vehicle emissions (to capture potential trends in pollutant concentrations over time) and with and without accounting for neighborhood-level mobility patterns (based on travel demand surveys). These exposure models were linked to members of the Canadian Census Health and Environment Cohorts (CanCHEC) residing in Montreal or Toronto (including census years 1991, 1996, 2001, and 2006) with mortality follow-up from 2001 (or cohort entry for the 2006 cohort) to 2016. Cox proportional hazard models were used to estimate associations between long-term exposures to outdoor UFPs and BC, adjusting for sociodemographic factors and co-pollutants identified as potential confounding factors. Concentration-response relationships for outdoor UFPs and BC were also examined for nonaccidental and cause-specific mortality using smoothing splines. RESULTS: Our cohort study included approximately 1.5 million people with 174,200 nonaccidental deaths observed during the follow-up period. Combined LUR and machine learning model predictions performed slightly better than LUR models alone and were used as the main exposure models in all epidemiological analyses. Long-term exposures to outdoor UFP number concentrations were consistently positively associated with nonaccidental and cause-specific mortality. Importantly, hazard ratios (HRs) for outdoor UFP number concentrations were sensitive to adjustment for UFP size: UFP size was inversely related to number concentrations and independently associated with mortality, resulting in underestimation of mortality risk for outdoor UFP number concentrations when UFP size was excluded. HRs for outdoor UFP number concentrations were robust to backcasting and mobility weighting but varied slightly in analyses using LUR and machine learning models alone, with stronger associations typically observed for the machine learning models. Associations between outdoor BC concentrations and mortality were generally weak or null, but a positive association was observed for cardiovascular mortality. CONCLUSIONS: Outdoor UFP number concentrations were consistently associated with increased risks of nonaccidental and cause-specific mortality in Montreal and Toronto. Our results suggest that UFP size should be considered in epidemiological analyses of outdoor UFP number concentrations, as excluding size can lead to an underestimation of health risks. Our results suggest that outdoor UFP number concentrations are positively associated with mortality independent of other outdoor air pollutants, including PM2.5 mass concentrations and oxidant gases (i.e., nitrogen dioxide [NO2] and ozone [O3]). As outdoor UFPs are currently unregulated, interventions targeting these pollutants could significantly affect population health.

Melatonin alleviates heme-induced ferroptosis via activating the Nrf2/HO-1 pathway in neurons.

OBJECTIVE: Ferroptosis of neurons is a significant cause of brain injury following intracerebral hemorrhage (ICH). As an iron-containing compound in hemoglobin, heme contributes to nerve injury post-ICH. Melatonin has been shown to mitigate the effects of ICH, yet its specific functions remain largely elusive. In this study, we aimed to explore the roles and mechanisms of melatonin in heme-induced ferroptosis subsequent to ICH. MATERIALS AND METHODS: C57BL/6 mice were intracranially injected with heme and then treated with melatonin. Behavior tests [modified neurological severity score (mNSS), forelimb placing, and corner turn tests], H&E staining, Nissl staining, and Prussian blue staining were used to evaluate mouse brain tissue injury. In vitro, HT-22 cells were stimulated with heme and cell viability was determined by crystal violet staining. The iron contents were determined in heme-treated brains and cells, and the levels of 4-hydroxynonenal (4-HNE) and malonaldehyde (MDA) were assessed by ELISA. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to investigate the mRNA levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). Immunoblotting was used to analyze the protein expression of glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), Nrf2, and HO-1. Finally, small interfering RNA (siRNA) was used to knock down Nrf2 in HT-22 cells. RESULTS: Melatonin treatment alleviated heme-induced injuries to neural function, as indicated by improved behavior in the mice. Moreover, melatonin decreased cell death and iron concentrations, increased MDA and 4-HNE levels, and reversed the decreases in GPX4, SLC7A11, Nrf2, and HO-1 induced by heme in vitro and in vivo. These results indicated that melatonin could improve the ferroptosis induced by heme. In addition, we found that Nrf2 knockdown attenuated the therapeutic effect of melatonin on neuronal ferroptosis induced by heme. CONCLUSIONS: In general, melatonin alleviates heme-induced ferroptosis by activating the Nrf2/HO-1 pathway, which implies that melatonin is a promising treatment for ferroptosis in ICH.

[Efficacy and feasibility of tunnel esophagogastrostomy to perform proximal gastrectomy].

Objective: To analyze the efficacy and feasibility of performing a new surgical procedure, tunnel esophagogastrostomy, to perform proximal gastrectomy. Methods: The study cohort comprised 10 consecutive patients who had undergone esophagogastrostomy by the tunnel technique in Jiangsu Cancer Hospital between October 2019 and July 2022. All patients were male. Their average age was (64.2±8.1) years and body mass index (25.5±3.2) kg/m2. Nine had upper gastric body adenocarcinoma, the remaining one having signet ring cell carcinoma. TNM staging of the tumors showed that seven were Stage IA, one Stage IB, one Stage IIA, and one Stage IIIA. Briefly, tunnel esophagogastrostomy is performed as follows: After performing a proximal gastrectomy, a rectangular seromuscular flap (3.0 cm × 3.5 cm) is created. The posterior esophageal wall is sutured to the gastric wall at the orad end of the seromuscular flap 5 cm from the stump with three to four stitches. Next, the stump of the esophagus is opened, the posterior esophageal wall is sutured to the gastric mucosa and submucosa, and the anterior esophageal wall is sutured to the full layer of the stomach. Finally, the caudad end of the seromuscular flap is closed. Data on surgical safety, postoperative morbidity, and postoperative reflux esophagitis were analyzed. All enrolled patients completed endoscopic follow-up 1 year and 2 years after surgery. Results: All procedures were completed. They comprised four cases of laparoscopic assisted surgery, four of DaVinci robotic surgery, and two of open surgery. The mean operation time was 212.7±33.2 mins, mean anastomosis time (51.6±5.3) minutes, mean tunnel preparation time (20.0±3.5) minutes, and mean operative blood loss (90.0±51.6) mL. The time to first postoperative passage of flatus was (64.8±11.5) hours. The mean hospital stay after surgery was (9.2±1.7) days. There were no postoperative complications above Clavien-Dindo Grade II. The mean preoperative Reflux Disease Questionnaire score was (3.3± 0.4) before the surgery, (3.8±1.0) 1 month postoperatively, and (3.3±0.4) 12 months postoperatively. All patients underwent endoscopic follow-up; no anastomotic stenoses were found. However, one patient had Grade A reflux esophagitis 1 year after surgery and another Grade B reflux esophagitis 2 years after surgery. Conclusion: Esophagogastrostomy by the tunnel technique is a safe and feasible means of performing proximal gastrectomy.

[The effect and mechanism of exposure to polystyrene nanoplastics on lipid metabolism in mice liver].

Objective: To investigate the effect and potential mechanism of exposure to 20 nm polystyrene nanoplastics (PS-NPs) on lipid metabolism in mice liver. Methods: An animal experimental model was designed, which was completed from September 2022 to July 2023 on the exposure omics platform of the School of Public Health at Capital Medical University and the Key Laboratory of Environment and Population Health at the Chinese Center for Disease Control and Prevention.1 mg/kg and 10 mg/kg PS-NPs tail vein mice exposure models were constructed. After exposure 7 d, serum was collected to measure the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and air flow assisted desorption electrospray ionization-mass spectrometry imaging (AFADESI-MSI) analysis were used to analyze the mRNA levels of fatty acid esterification related genes (Dgat1 and Dgat2) and lipid transport related genes (ApoB, Cd36, ApoE and Mttp) and metabolites' spatial changes in liver tissue. In vivo imaging system (IVIS) and tissue shake sections were employed to observe the fluorescence biological distribution of PS-NPs. t-test or one-way ANOVA was used to explore the difference between groups. Results: The serum ALT levels were (83.97±4.58), (91.17±13.69) and (142.43±6.09) U/L in the control group, 1 mg/kg PS-NPs exposure group and 10 mg/kg PS-NPs exposure group respectively (F=37.281, P<0.05). The relative mRNA levels of Dgat1, Dgat2, ApoB, Cd36 and ApoE were (1.49±0.63, 2.53±0.32, 2.45±0.54), (1.07±0.38, 1.86±0.83, 2.23±0.73), (1.01±0.13, 1.58±0.43, 2.03±0.52), (1.01±0.14, 1.55±0.37, 1.52±0.51), (1.01±0.17, 2.11±0.27, 2.39±0.93) in these three groups respectively. The differences were statistically significant (F=11.54, 6.95, 14.90, 5.98 and 14.68, P<0.05). AFADESI-MSI analysis found that PS-NPs exposure led to a significant decrease in the levels of glutarylcarnitine and O-Linoleoylcarnitine (t=4.12 and 3.35, P<0.05), which were associated with lipid beta oxidation. The content of triglycerides (TG) (m/z 921.726 4, t=8.69, P<0.05; m/z 919.711 4, t=3.20, P<0.05), phosphatidylic acid (PA) (m/z 895.712 3, t=3.60, P<0.05; m/z 821.526 6, t=3.36, P<0.05), lysophosphatidylcholine (LysoPC) (m/z 560.310 6, t=3.35, P<0.05; m/z 582.295 3, t=6.28, P<0.05), phosphatidylcholine (PC) (m/z 778.533 9, t=3.53, P<0.05; m/z 804.549 6, t=3.60, P<0.05; m/z 820.523 1, t=3.37, P<0.05), phosphatidylethanolamine (PE) (m/z 772.523 3, t=3.08, P<0.05) showed a significant increase in the PS-NPs exposure group. In vivo and in vitro imaging and in situ cell localization revealed that PS-NPs were mainly enriched in hepatic stellate cells and hepatic Kupffer cells in liver tissue. Conclusion: Exposure to PS-NPs induces disorder of liver lipid metabolism, which may be related to the accumulation of PS-NPs in hepatic stellate cells and hepatic Kupffer cells, providing basis for searching early biomarkers of PS-NPs exposure and further mechanism research.

Search for Rare Decays of D_{s}

Using 7.33 fb^{-1} of e^{+}e^{-} collision data collected by the BESIII detector at center-of-mass energies in the range of sqrt[s]=4.128-4.226 GeV, we search for the rare decays D_{s}^{+}→h^{+}(h^{0})e^{+}e^{-}, where h represents a kaon or pion. By requiring the e^{+}e^{-} invariant mass to be consistent with a ϕ(1020), 0.98

The sixth sense: how much does interictal intracranial EEG add to determining the focality of epileptic networks?

Intracranial EEG is used for two main purposes: to determine (i) if epileptic networks are amenable to focal treatment and (ii) where to intervene. Currently, these questions are answered qualitatively and differently across centres. There is a need to quantify the focality of epileptic networks systematically, which may guide surgical decision-making, enable large-scale data analysis and facilitate multi-centre prospective clinical trials. We analysed interictal data from 101 patients with drug-resistant epilepsy who underwent pre-surgical evaluation with intracranial EEG at a single centre. We chose interictal data because of its potential to reduce the morbidity and cost associated with ictal recording. Sixty-five patients had unifocal seizure onset on intracranial EEG, and 36 were non-focal or multi-focal. We quantified the spatial dispersion of implanted electrodes and interictal intracranial EEG abnormalities for each patient. We compared these measures against the '5 Sense Score,' a pre-implant prediction of the likelihood of focal seizure onset, assessed the ability to predict unifocal seizure onset by combining these metrics and evaluated how predicted focality relates to subsequent treatment and outcomes. The spatial dispersion of intracranial EEG electrodes predicted network focality with similar performance to the 5-SENSE score [area under the receiver operating characteristic curve = 0.68 (95% confidence interval 0.57, 0.78)], indicating that electrode placement accurately reflected pre-implant information. A cross-validated model combining the 5-SENSE score and the spatial dispersion of interictal intracranial EEG abnormalities significantly improved this prediction [area under the receiver operating characteristic curve = 0.79 (95% confidence interval 0.70, 0.88); P < 0.05]. Predictions from this combined model differed between surgical- from device-treated patients with an area under the receiver operating characteristic curve of 0.81 (95% confidence interval 0.68, 0.85) and between patients with good and poor post-surgical outcome at 2 years with an area under the receiver operating characteristic curve of 0.70 (95% confidence interval 0.56, 0.85). Spatial measures of interictal intracranial EEG abnormality significantly improved upon pre-implant predictions of network focality by area under the receiver operating characteristic curve and increased sensitivity in a single-centre study. Quantified focality predictions related to ultimate treatment strategy and surgical outcomes. While the 5-SENSE score weighed for specificity in their multi-centre validation to prevent unnecessary implantation, sensitivity improvement found in our single-centre study by including intracranial EEG may aid the decision on whom to perform the focal intervention. We present this study as an important step in building standardized, quantitative tools to guide epilepsy surgery.

Dithiocarbamate fungicides suppress aromatase activity in human and rat aromatase activity depending on structures: 3D-QSAR analysis and molecular simulation.

Dithiocarbamate fungicides have been widely used in agricultural practices due to their effective control of fungal diseases, thereby contributing to global food security and agricultural productivity. In this study, the inhibitory potency of eight compounds on human and rat aromatase (CYP19A1) activity was evaluated. The results revealed that zineb exhibited the highest inhibitory potency on human CYP19A1 (IC50, 2.79 µM). Maneb (IC50, 3.09 µM), thiram (IC50, 4.76 µM), and ferbam (IC50, 6.04 µM) also demonstrated potent inhibition on human CYP19A1. For the rat CYP19A1, disulfiram (IC50, 1.90 µM) displayed the strongest inhibition followed by maneb (2.16 µM), zineb (2.54 µM), and thiram (6.99 µM). These dithiocarbamates acted as mixed/non-competitive inhibitors of human and rat CYP19A1. Dithiothreitol (DTT), a reducing agent, partially rescued thiram-mediated inhibition when incubated at the same. Moreover, positive correlations were observed between log P, topological polar surface area, molecular weight, and heavy atoms and IC50 values. 3D-QSAR analysis revealed the hydrogen bond acceptor and donor play critical roles in the binding of dithiocarbamates to human CYP19A1. In silico analysis showed that dithiocarbamates bind to the haem binding site, containing Cys437 residues. In conclusion, some dithiocarbamates potently inhibit human and rat CYP19A1 via interacting with haem-binding Cys437 residues.

Metabolite analysis of peach (Prunus persica L. Batsch) branches in response to freezing stress.

Cold resistance in fruit trees has a direct impact on food production and scientific studies. 'Donghe No.1' is an excellent cold-tolerant peach variety. Metabolomic changes under freezing stress were examined to understand the mechanisms of cold adaptation. The UPLC-MS/MS system was used to identify differentially expressed metabolites (DEMs) in branches of 'Donghe No.1' under freezing stress for 12 h at -5°C, -20°C, -25°C, or -30°C. In total, 1096 metabolites and 196 DEMs were obtained at -5°C vs -20°C, -25°C, and - 30°C, while 179 DEMs and eight shared DEMs obtained at -5°C vs -20°C, -20°C vs -25°C, and -25°C vs -30°C. KEGG enrichment identified 196 DEMs associated with amino acid metabolism, linoleic acid metabolism, alpha-linolenic acid metabolism, phenylpropanoid biosynthesis, and flavonoid biosynthesis under freezing stress. A metabolic network in 1-year-old peach branches under freezing stress is proposed. Moreover, these results enhance understanding of metabolite responses and mechanisms to freezing stress in peach and will help in future breeding of freezing-tolerant varieties and investigating tolerance mechanisms.

Measurement of Electron Antineutrino Oscillation Amplitude and Frequency via Neutron Capture on Hydrogen at Daya Bay.

This Letter reports the first measurement of the oscillation amplitude and frequency of reactor antineutrinos at Daya Bay via neutron capture on hydrogen using 1958 days of data. With over 3.6 million signal candidates, an optimized candidate selection, improved treatment of backgrounds and efficiencies, refined energy calibration, and an energy response model for the capture-on-hydrogen sensitive region, the relative ν[over ¯]_{e} rates and energy spectra variation among the near and far detectors gives sin^{2}2θ_{13}=0.0759_{-0.0049}^{+0.0050} and Δm_{32}^{2}=(2.72_{-0.15}^{+0.14})×10^{-3} eV^{2} assuming the normal neutrino mass ordering, and Δm_{32}^{2}=(-2.83_{-0.14}^{+0.15})×10^{-3} eV^{2} for the inverted neutrino mass ordering. This estimate of sin^{2}2θ_{13} is consistent with and essentially independent from the one obtained using the capture-on-gadolinium sample at Daya Bay. The combination of these two results yields sin^{2}2θ_{13}=0.0833±0.0022, which represents an 8% relative improvement in precision regarding the Daya Bay full 3158-day capture-on-gadolinium result.

[Clinical analysis of allogeneic hematopoietic cell transplantation in 9 patients with hematological malignancies complicated by Gilbert's syndrome].

From January 1, 2013, to March 1, 2024, nine patients with hematological malignancies complicated by Gilbert's syndrome in Peking University People's Hospital underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). The patients comprised seven male and two female cases, with a median age of 38 (13-60) years old. Among them, three cases were acute myeloid leukemia, three cases were acute lymphocytic leukemia, two cases were myelodysplastic syndrome, and one case was chronic myelomonocytic leukemia. None of the patients had viral hepatitis. Of the nine cases, seven cases received the Bu-Cy+ATG regimen, while the other two cases received the TBI-Cy+ATG regimen (Bu, busulfan; Cy, cyclophosphamide; ATG, antithymocyte immunoglobulin; and TBI, total body irradiation). All patients achieved neutrophil engraftment, and eight received platelet engraftment. The median total bilirubin level was 45.4 (22.5-71.2) µmol/L before transplantation and 22.0 (18.0-37.2) µmol/L on -1d of preconditioning. The total bilirubin level on +20d after the transplantation of eight patients decreased compared with the baseline level before transplantation. Moreover, one patient had a transient increase in the total bilirubin level on +5d after transplantation, which was considered to be attributed to the toxicity of Bu. No patients were complicated by hepatic veno-occlusive disease. The median follow-up time was 739 (42-2 491) days. During the follow-up period, one patient died of recurrence, and the remaining eight patients had disease-free survival events.

[Association of serum 25(OH)D3 with cardiovascular risk-related indicators: cross-sectional analysis of NHANES].

This study investigated the association between serum 25(OH)D3 levels and cardiovascular risk-related indicators. 4 727 participants aged 20 and above from the National Health and Nutrition Examination Survey 2015-2018 database were enrolled. Body mass index, hypersensitive C-reactive protein, high density lipoprotein cholesterol, systolic blood pressure, waist-height ratio, and total cholesterol were selected as the research indicators. Weighted multiple linear regression models, subgroup analyses, smooth curve fitting, and saturation threshold effect analyses were employed to explore the relationship between serum 25(OH)D3 and these indicators. The results showed that after full adjustment for covariates, every 1 nmol/L increase in serum 25(OH)D3, the changes in ß (95%CI) values for body mass index(BMI), hypersensitive C-reactive protein(hs-CRP), systolic blood pressure(SBP), waist-height ratio(WHtR), high density lipoprotein cholesterol(HDL-C), and total cholesterol(TC) were -0.05 (-0.06, -0.04) kg/m2, -0.01 (-0.02, -0.01) mg/L, -0.02 (-0.04, -0.01) mmHg, -0.000 7 (-0.000 8, -0.000 6), 0.10 (0.08, 0.11) mg/dl, and 0.08 (0.04, 0.12) mg/dl, respectively. Female participants were more sensitive to changes in serum 25(OH)D3, while participants aged 60 and above were relatively less sensitive. The relationship between serum 25(OH)D3 and these indicators partially exhibited nonlinear patterns across different gender and age subgroups. The saturation threshold effect analysis revealed 8 meaningful inflection points. In summary, vitamin D has a close association with cardiovascular risk-related indicators.

[Distribution and seasonal fluctuation of visceral leishmaniasis vectors sandflie in Lüliang City of Shanxi Province in 2023].

OBJECTIVE: To investigate the distribution and seasonal fluctuations of visceral leishmaniasis vectors sandflies in Lüliang City, Shanxi Province, so as to provide insights into assessment of the visceral leishmaniasis transmission risk and formulation of visceral leishmaniasis control measures. METHODS: A total of 12 natural villages were sampled from Shilou County, Lishi District, Lanxian County, Linxian County and Wenshui County in Lüliang City, Shanxi Province from June to September, 2023, and sandflies were captured using light traps from 7 breeding habitats, including farmers' houses, sheep pens, cattle pens, chicken coops, pig pens, mule and horse pens, and loess-cave dwellings. Following morphological identification of the sandfly species, the distribution of sandflies and the seasonal fluctuations of the sandfly density were analyzed. In addition, the Leishmania was detected in sandflies using a real-time fluorescence quantitative PCR assay. RESULTS: A total of 2 831 sandflies were captured with 156 light traps in Lüliang City from June to September, 2023, including 2 638 female sandflies (93.18%) and 193 male sandflies (6.82%), and the average density was 16.91 sandflies/(light-night). The seasonal fluctuations of the sandfly density all appeared a unimodal distribution in all survey sites, and the sandfly density peaked in July and then declined rapidly. Among all types of breeding habitats, the greatest sandfly density was found in sheep pens [39.04 sandflies/(light-night)]. In addition, 4.08% (2/49) of the sandfly samples were tested positive for Leishmania nucleic acid as revealed by the real-time fluorescence quantitative PCR assay. CONCLUSIONS: Sandflies were widely distributed in Lüliang City, Shanxi Province in 2023, and the peak of the sandfly density was observed in July, which had a visceral leishmaniasis transmission risk. Intensified surveillance of visceral leishmaniasis and sandfly vectors is required and targeted vector control is recommended.

Learning from each other: Cross-cutting diagnostic development activities between magnetic and inertial confinement fusion (invited).

Inertial Confinement Fusion and Magnetic Confinement Fusion (ICF and MCF) follow different paths toward goals that are largely common. In this paper, the claim is made that progress can be accelerated by learning from each other across the two fields. Examples of successful cross-community knowledge transfer are presented that highlight the gains from working together, specifically in the areas of high-resolution x-ray imaging spectroscopy and neutron spectrometry. Opportunities for near- and mid-term collaboration are identified, including in chemical vapor deposition diamond detector technology, using gamma rays to monitor fusion gain, handling neutron-induced backgrounds, developing radiation hard technology, and collecting fundamental supporting data needed for diagnostic analysis. Fusion research is rapidly moving into the igniting and burning regimes, posing new opportunities and challenges for ICF and MCF diagnostics. This includes new physics to probe, such as alpha heating; increasingly harsher environmental conditions; and (in the slightly longer term) the need for new plant monitoring diagnostics. Substantial overlap is expected in all of these emerging areas, where joint development across the two subfields as well as between public and private researchers can be expected to speed up advancement for all.

[New intraoral digital impression with pneumatic gingival retraction used in the restoration of crown for posterior teeth: a case report].

In fixed prosthodontics, clear exposure of the preparation margin is the prerequisite for obtaining accurate digital impressions and improving the marginal fit of restorations. To resolve the issues associated with the cord retraction technique, such as pain, acute injury, and prolonged procedural time, this study proposes a new technology for intraoral digital impression taking with pneumatic gingival retraction. The new scanning head blows a high-speed airflow that instantaneously separates the free gingiva, locally exposing the subgingival preparation margin. Combined with the farthest point preservation stitching algorithm based on the distance from the normal vector and high-speed laser scanning photography, it achieves global preparation edge data and gingival reconstruction, realizing painless, non-invasive, and efficient precise acquisition of the preparation margin. Using this new technique, a patient with a full porcelain crown restoration on a posterior tooth was treated. The digital impression revealed a clear margin of the preparation, and the crown made from this data has a good marginal fit.

Strong and Weak CP Tests in Sequential Decays of Polarized Σ

The J/ψ, ψ(3686)→Σ^{0}Σ[over ¯]^{0} processes and subsequent decays are studied using the world's largest J/ψ and ψ(3686) data samples collected with the BESIII detector. The parity-violating decay parameters of the decays Σ^{0}→Λγ and Σ[over ¯]^{0}→Λ[over ¯]γ, α_{Σ^{0}}=-0.0017±0.0021±0.0018 and α[over ¯]_{Σ^{0}}=0.0021±0.0020±0.0022, are measured for the first time. The strong CP symmetry is tested in the decays of the Σ^{0} hyperons for the first time by measuring the asymmetry A_{CP}^{Σ}=α_{Σ^{0}}+α[over ¯]_{Σ^{0}}=(0.4±2.9±1.3)×10^{-3}. The weak CP test is performed in the subsequent decays of their daughter particles Λ and Λ[over ¯]. Also for the first time, the transverse polarizations of the Σ^{0} hyperons in J/ψ and ψ(3686) decays are observed with opposite directions, and the ratios between the S-wave and D-wave contributions of the J/ψ, ψ(3686)→Σ^{0}Σ[over ¯]^{0} decays are obtained. These results are crucial to understand the decay dynamics of the charmonium states and the production mechanism of the Σ^{0}-Σ[over ¯]^{0} pairs.