A decision tree model to distinguish between benign and malignant pulmonary nodules on CT scans

OBJECTIVE

Chest computed tomography (CT) is increasingly being used to screen for lung cancer. Machine learning models could facilitate the distinction between benign and malignant pulmonary nodules. This study aimed to develop and validate a simple clinical prediction model to distinguish between benign and malignant lung nodules.

PATIENTS AND METHODS

Patients who underwent a video thoracic-assisted lobectomy between January 2013 and December 2020 at a Chinese hospital were enrolled in the study. The clinical characteristics of the patients were extracted from their medical records. Univariate and multivariate analyses were used to identify the risk factors for malignancy. A decision tree model with 10-fold cross-validation was constructed to predict the malignancy of the nodules. The sensitivity, specificity, and area under the curve (AUC) of a receiver operatic characteristics curve were used to evaluate the model's prediction accuracy in relation to the pathological gold standard.

RESULTS

Out of the 1,199 patients with pulmonary nodules enrolled in the study, 890 were pathologically confirmed to have malignant lesions. The multivariate analysis identified satellite lesions as an independent predictor for benign pulmonary nodules. Conversely, the lobulated sign, burr sign, density, vascular convergence sign, and pleural indentation sign were identified as independent predictors for malignant pulmonary nodules. The decision tree analysis identified the density of the lesion, the burr sign, the vascular convergence sign, and the drinking history as predictors of malignancy. The area under the curve of the decision tree model was 0.746 (95% CI 0.705-0.778), while the sensitivity and specificity were 0.762 and 0.799, respectively.

CONCLUSIONS

The decision tree model accurately characterized the pulmonary nodule and could be used to guide clinical decision-making.

Improved Measurement of the Evolution of the Reactor Antineutrino Flux and Spectrum at Daya Bay

Reactor neutrino experiments play a crucial role in advancing our knowledge of neutrinos. In this Letter, the evolution of the flux and spectrum as a function of the reactor isotopic content is reported in terms of the inverse-beta-decay yield at Daya Bay with 1958 days of data and improved systematic uncertainties. These measurements are compared with two signature model predictions: the Huber-Mueller model based on the conversion method and the SM2018 model based on the summation method. The measured average flux and spectrum, as well as the flux evolution with the ^{239}Pu isotopic fraction, are inconsistent with the predictions of the Huber-Mueller model. In contrast, the SM2018 model is shown to agree with the average flux and its evolution but fails to describe the energy spectrum. Altering the predicted inverse-beta-decay spectrum from ^{239}Pu fission does not improve the agreement with the measurement for either model. The models can be brought into better agreement with the measurements if either the predicted spectrum due to ^{235}U fission is changed or the predicted ^{235}U, ^{238}U, ^{239}Pu, and ^{241}Pu spectra are changed in equal measure.

Precision Measurement of Reactor Antineutrino Oscillation at Kilometer-Scale Baselines by Daya Bay

We present a new determination of the smallest neutrino mixing angle θ_{13} and the mass-squared difference Δm_{32}^{2} using a final sample of 5.55×10^{6} inverse beta-decay (IBD) candidates with the final-state neutron captured on gadolinium. This sample is selected from the complete dataset obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are sin^{2}2θ_{13}=0.0851±0.0024, Δm_{32}^{2}=(2.466±0.060)×10^{-3}  eV^{2} for the normal mass ordering or Δm_{32}^{2}=-(2.571±0.060)×10^{-3}  eV^{2} for the inverted mass ordering.

First Measurement of High-Energy Reactor Antineutrinos at Daya Bay

This Letter reports the first measurement of high-energy reactor antineutrinos at Daya Bay, with nearly 9000 inverse beta decay candidates in the prompt energy region of 8-12 MeV observed over 1958 days of data collection. A multivariate analysis is used to separate 2500 signal events from background statistically. The hypothesis of no reactor antineutrinos with neutrino energy above 10 MeV is rejected with a significance of 6.2 standard deviations. A 29% antineutrino flux deficit in the prompt energy region of 8-11 MeV is observed compared to a recent model prediction. We provide the unfolded antineutrino spectrum above 7 MeV as a data-based reference for other experiments. This result provides the first direct observation of the production of antineutrinos from several high-Q_{β} isotopes in commercial reactors.

[Comparative analysis of population distribution, severity, emotional, and cognitive characteristics among different side idiopathic tinnitus patients]

To provide basis for prevention and treatment by analyzing the clinical features, emotional and cognitive states and their correlations of idiopathic tinnitus. Cross-sectional study was used. Thirty-six right, 44 left, and 46 bilateral idiopathic tinnitus patients diagnosed in Beijing Tongren Hospital were prospectively enrolled from October, 2020 to February, 2022. The clinical data was recorded and the THI, DBI, STAI, and MoCA were evaluated. The clinical features and the incidence of severe tinnitus, hearing lose, anxiety, and cognitive impairment were compared by one-way ANOVA, Kruskal-Wallis H, and chi-square test. The correlation between tinnitus or hearing and emotional and cognitive states were evaluated by multivariable correlation analysis. There was no significant difference in age, BMI, years of education, tinnitus duration, and the incidence of hearing loss among groups (F=0.730,P=0.484;F=1.535,P=0.219;F=1.506,P=0.226;χ²=4.242,P=0.120;χ²=6.672,P=0.083). In right, left, and bilateral tinnitus patients, the number of severe tinnitus was 12, 7, and 20 cases and the incidence was 33.3%, 15.9%, and 43.5%; the number of depression was 13, 14, and 26 cases and incidence was 36.1%, 31.8%, and 53.5%; the number of trait anxiety was 3, 2, and 10 cases and the incidence was 8.3%, 4.5%, and 21.7%. Compared with left tinnitus patients, the incidence of severe tinnitus, depression, and trait anxiety was higher in bilateral tinnitus patients (χ²=8.139,P=0.004;χ²=5.558,P=0.018;χ²=5.753,P=0.007). The incidence of state anxiety and cognitive impairment were no significant difference among groups (χ²=0.142,P=0.931;χ²=1.338,P=0.512). The overall incidence of state anxiety and cognitive impairment were 16.7%(21/126) and 37.3%(47/126) respectively. There was positive correlation between THI score and BDI, S-AI, and T-AI scores (r=0.529,P=0.001; r=0.649,P<0.001; r=0.483,P=0.003) and negative correlation between THI and MoCA scores (r=-0.364,P=0.029) in right tinnitus group. The positive correlation was found between THI score and BDI, S-AI, and T-AI scores in left tinnitus group (r=0.508,P<0.001; r=0.506,P<0.001; r=0.357,P=0.017). The positive correlation between THI score and BDI, S-AI, and T-AI scores (r=0.753,P<0.001; r=0.527,P<0.001; r=0.536,P<0.001) and the positive correlation between tinnitus duration and MoCA score(r=0.334,P=0.023) were also found in bilateral tinnitus group.

Joint Determination of Reactor Antineutrino Spectra from ^{235}U and ^{239}Pu Fission by Daya Bay and PROSPECT

A joint determination of the reactor antineutrino spectra resulting from the fission of ^{235}U and ^{239}Pu has been carried out by the Daya Bay and PROSPECT Collaborations. This Letter reports the level of consistency of ^{235}U spectrum measurements from the two experiments and presents new results from a joint analysis of both data sets. The measurements are found to be consistent. The combined analysis reduces the degeneracy between the dominant ^{235}U and ^{239}Pu isotopes and improves the uncertainty of the ^{235}U spectral shape to about 3%. The ^{235}U and ^{239}Pu antineutrino energy spectra are unfolded from the jointly deconvolved reactor spectra using the Wiener-SVD unfolding method, providing a data-based reference for other reactor antineutrino experiments and other applications. This is the first measurement of the ^{235}U and ^{239}Pu spectra based on the combination of experiments at low- and highly enriched uranium reactors.

Low expression of CircRNA HIPK3 promotes osteoarthritis chondrocyte apoptosis by serving as a sponge of miR-124 to regulate SOX8

OBJECTIVE

CircRNA, a type of circular RNA, has recently been shown to be a potential target for osteoarthritis (OA). Circular RNA HIPK3 (CircHIPK3) is reported to be abnormally expressed in various disease tissues and affects the occurrence and development of the disease. However, the role and underlying mechanism of CircRNA HIPK3 in osteoarthritis are still unclear. The purpose of this study is to explore the effect of CircRNA HIPK3 on osteoarthritis and analyze its regulatory mechanism.

PATIENTS AND METHODS

We took human OA tissues, normal knee cartilage, human OA chondrocytes and normal chondrocytes as the research objects. Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was used to detect CircHIPK3 expression level, its target gene miRNA 124 (miR-124) and downstream target molecule SOX8. Flow cytometry analysis was applied to discover the apoptosis of CircHIPK3 and miR-124 on OA cartilage in different transfection situations. Moreover, Western blot and RT-qPCR were used to detect the expression of caspase-3 in OA chondrocytes. The binding site of CircRNA HIPK3 and miR-124, miR-124, and SOX8 were verified by using Dual-Luciferase assay.

RESULTS

High expressed CircHIPK3 and low expressed miR-124 were found in OA tissues and OA chondrocytes. In addition, the Dual-Luciferase report showed CircHIPK3 acted as a sponge of miR-124 in OA chondrocytes. CircHIPK3 and miR-124 expression in OA tissue were confirmed to be negatively correlated. To our surprise, knocking down CircHIPK3 and transfected miR-124 mimics both inhibited the apoptosis of OA chondrocytes. Further experiments verified that the downstream target molecule of miR-124 was SOX8 in OA chondrocytes. Besides, miR-124 inhibitors reversed the knockdown of CircHIPK3 while si-SOX8 reversed the miR-124 inhibitors effect of apoptosis on OA chondrocytes.

CONCLUSIONS

Our results demonstrated that CircHIPK3 was significantly upregulated in OA cartilage tissue and cells. Low expression of CircHIPK3 promoted the apoptosis of OA chondrocytes by promoting miR-124 to suppress SOX8 expression. The molecular mechanism of CircHIPK3 in present study is expected to provide new ideas for the treatment of osteoarthritis.

Improved Constraints on Sterile Neutrino Mixing from Disappearance Searches in the MINOS, MINOS+, Daya Bay, and Bugey-3 Experiments

Searches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on the θ_{μe} mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Δm_{41}^{2}, excluding the 90% C.L. sterile-neutrino parameter space allowed by the LSND and MiniBooNE observations at 90% CL_{s} for Δm_{41}^{2}<13  eV^{2}. Furthermore, the LSND and MiniBooNE 99% C.L. allowed regions are excluded at 99% CL_{s} for Δm_{41}^{2}<1.6 eV^{2}.

[Correlation analysis of Sema4D with rheumatoid arthritis disease activity, bone destruction and rheumatoid arthritis-related interstitial lung disease]

Objective: To explore the correlation between Semaphorin 4D (Sema4D) and rheumatoid arthritis (RA) clinical manifestations, laboratory indexes, bone destruction and rheumatoid arthritis related interstitial lung disease(RA-ILD), and to analyze its significance in evaluating the severity of patients with rheumatoid arthritis. Methods: A total of 108 RA patients and 50 healthy controls from September 2018 to October 2019 were collected from the Department of Rheumatology and Immunology, Peking University People's Hospital and Beijing Haidian Hospital. According to the DAS 28 score, RA patients were divided into active disease group (DAS28>2.6) and stable disease group (DAS28 ≤ 2.6). Fifty healthy controls. The levels of Sema4D in serum were detected by enzyme-linked immunoassay method (ELISA), and their correlation with clinical manifestations of RA, laboratory indicators, degree of bone damage and RA-ILD were analyzed. Results: The level of serum Sema4D in RA active group was significantly higher than that in stable group and healthy control group (P<0.05). The concentration serum Sema4D was positively correlated with C-reactive protein(CRP) (r=0.28, P<0.05), rheumatoid factor(RF) (r=0.25, P<0.05) and the 28-joint disease activity score (DAS28) (r=0.45, P<0.01). The concentration serum Sema4D was positively correlated with β-Crosslaps(r=0.20, P<0.05) and Sharp-van der Heijde score (SHS)(r=0.13, P<0.05). The concentration serum Sema4D was positively correlated with Vascular endothelial growth factor (VEGF)(r=0.25, P<0.05) and Warrick score of chest CT in RA patients(r=0.27, P<0.05). The anti-cyclic citrullinated peptid(CCP) antibody, DAS28, VEGF and the incidence of RA-ILD were significantly higher than that in Sema4D negative group (P<0.05). Conclusions: Serum Sema4D level in RA patients is closely related to the disease activity, bone destruction and RA-ILD. Serum Sema4D can be used as an indicator of disease monitoring and prognosis evaluation in RA patients.

[Historian Morris's correspondence, book review and obituary about Wu Lien-teh]

After reading Wu Lien-teh's Plague Fighter: The Autobiography of a Modern Chinese Physician, Morris wrote to Joseph Needham, proposing to award an honorary degree from Emmanuel College in Cambridge to Mr.Wu. He, then, wrote a book review in Cambridge Review introducing Wu Lien-teh's autobiography After Wu Lien-teh's death, he wrote an obituary published in the Times, giving Wu Lien-teh highly praised.

Extraction of the ^{235}U and ^{239}Pu Antineutrino Spectra at Daya Bay

This Letter reports the first extraction of individual antineutrino spectra from ^{235}U and ^{239}Pu fission and an improved measurement of the prompt energy spectrum of reactor antineutrinos at Daya Bay. The analysis uses 3.5×10^{6} inverse beta-decay candidates in four near antineutrino detectors in 1958 days. The individual antineutrino spectra of the two dominant isotopes, ^{235}U and ^{239}Pu, are extracted using the evolution of the prompt spectrum as a function of the isotope fission fractions. In the energy window of 4-6 MeV, a 7% (9%) excess of events is observed for the ^{235}U (^{239}Pu) spectrum compared with the normalized Huber-Mueller model prediction. The significance of discrepancy is 4.0σ for ^{235}U spectral shape compared with the Huber-Mueller model prediction. The shape of the measured inverse beta-decay prompt energy spectrum disagrees with the prediction of the Huber-Mueller model at 5.3σ. In the energy range of 4-6 MeV, a maximal local discrepancy of 6.3σ is observed.

[An analysis of the results of video head impulse test in benign paroxysmal vertigo of childhood]

Objective:This study was to analyze the results of video head impulse test (vHIT) of benign paroxysmal vertigo of childhood (BPVC) in order to determine the potential value of vHIT in the diagnosis and treatment for BPVC and to discuss its possible pathogenesis of BPVC. Method:Thirty-six children with BPVC were enrolled. No hearing loss and skull abnormality were found in these children as assessed by pure tone audiometry, acoustic impedance, CT or MRI scan. The vHIT was carried out, and main outcome measures were the gain of vestibulo-ocular reflex, gain asymmetry, and refixation saccades. Eleven healthy children were selected as normal control who came to our hospital for doing a routine checkup and have no history of dizziness. The differences of vHIT results between these two groups were analyzed. Result:①The vHIT results in control group were normal. In all BPVC subjects, abnormalities were detected in 9 patients (25.0%),including vHIT gains decline in 3 patients, abnormal symmetry in 4 patients, and abnormal isolated overt saccades in 2 patients.②The average saccadic gain in different canals of BPVC group was 1.03±0.14, 1.01±0.15, 1.13±0.31, 1.18±0.36, 1.21±0.33, 1.14±0.30 in left horizontal, right horizontal, left anterior, right posterior, right anterior, left posterior canal, respectively; while in normal group, it was 1.14±0.15, 1.18±0.09, 1.16±0.30, 1.18±0.40, 1.34±0.26, 1.30±0.20, respectively. Significant statistical difference was found only in horizontal canals between these two groups (P<0.05). ③Asymmetry of the three pairs of conjugated semicircular canals was 0.04±0.07 (horizontal canal), 0.06±0.04 (left anterior and right posterior canal), 0.06±0.04 (right anterior and left posterior canal) in BPVC group, respectively; while in control group, it was 0.02±0.02, 0.04±0.03, 0.04±0.04,respectively. There was no statistical difference between the two groups (P>0.05). Conclusion:A certain proportion of abnormal peripheral vestibule function in children with BPVC was found. vHIT is a "child friendly," relatively easytouse, and simple tool to evaluate each of the 6 semicircular canals, which may offer some potential clinical information for assessing the vestibule dysfunction for BPVC.

[Congenital microtia with aural atresia or stenosis accompany with first branchial cleft anomaly: report of 5 cases]

Objective: To summarize the experience of the diagnosis, treatment and effects of the cases with coexistence of first branchial cleft anomaly(FBCA) and microtia with congenital aural atresia or stenosis(external auditory canal stenosis, EACS). Method: This was a retrospective study. The clinical data of 5 patients with microtia and EACS in Beijing Tongren Hospital of Capital Medical University from October 2015 to March 2018 were collected, including 3 males and 2 females, aged from 5 to 28 years. The clinical characteristics, imaging findings, treatment methods and effects of 5 patients were analyzed. Result: The 5 cases were all coexistence of EACS and FBCA, three of who associated with cholesteatoma of external auditory canal. CT showed external auditory canal stenosis with soft tissue shadow, sometimes gas or bone septum found inside, filling in the external auditory canal, combined with canal bone destruction irregularly. All patients underwent surgical resection of FBCA, 3 patients accompanied by cholesteatoma resection and canalplasty. The postoperative follow-up ranged from 10 to 39 months, and no recurrence of infection was observed. Conclusions: EACS and FBCA both result from maldevelopment of the first branchial cleft. These two malformations, FBCA and EACS with or without cholesteatoma, can occur simultaneously, in which situation CT shows external auditory canal stenosis with soft tissue shadow inside. These patients underwent surgical resection of FBCA combined with cholesteatoma resection with good result.

Measurement of the Electron Antineutrino Oscillation with 1958 Days of Operation at Daya Bay

We report a measurement of electron antineutrino oscillation from the Daya Bay Reactor Neutrino Experiment with nearly 4 million reactor ν[over ¯]_{e} inverse β decay candidates observed over 1958 days of data collection. The installation of a flash analog-to-digital converter readout system and a special calibration campaign using different source enclosures reduce uncertainties in the absolute energy calibration to less than 0.5% for visible energies larger than 2 MeV. The uncertainty in the cosmogenic ^{9}Li and ^{8}He background is reduced from 45% to 30% in the near detectors. A detailed investigation of the spent nuclear fuel history improves its uncertainty from 100% to 30%. Analysis of the relative ν[over ¯]_{e} rates and energy spectra among detectors yields sin^{2}2θ_{13}=0.0856±0.0029 and Δm_{32}^{2}=(2.471_{-0.070}^{+0.068})×10^{-3}  eV^{2} assuming the normal hierarchy, and Δm_{32}^{2}=-(2.575_{-0.070}^{+0.068})×10^{-3}  eV^{2} assuming the inverted hierarchy.

[The implantation of Bonebridge in bilateral congenital malformation of external and middle ear]

Objective: To evaluate the auditory efficacy of Bonebridge implantation in patients with bilateral congenital malformation of external and middle ear. Methods: Eleven cases (6 males and 5 females) had unilateral Bonebridge implantation. The age ranged from 8 to 26 and the average age was 16.9. Seven to ten days after operation, the first fitting was undergone. In acoustic sound field, the average auditory thresholds were respectively measured for unaided ears and Bonebridge implanted ears by pure tone auditory (PTA, 0.25, 0.5, 1, 2 and 4 kHz). For the group over 12-year-old, MSTM was applied to evaluate speech discrimination score (SDS). For the other cases, MLNT was used as the test material. The auditory efficacy post Bonebridge implantation would be analyzed and evaluated by comparing the differences between unaided ears and Bonebridge implanted ears. Results: The bone conduction audibility threshold after Bonebridge implantation was as well as the preoperative. The auditory threshold with Bonebridge aided was improved to 25-35 dB HL, when compared to that of the unaided ears in the sound field. The SDS in the group over 12-year-old was improved about 50%; the efficacy was slightly limited for the other two cases (both less than 12 years old). Statistical analysis showed that there were significant differences between unaided ears and Bonebridge implanted ears in the sound field and SDS(P<0.05). Conclusions: The auditory efficacy of Bonebridge is significant and noticeable in patients with bilateral congenital malformation of external and middle ear. Bonebridge provides a new and effective way for patient with congenital malformation of external and middle ear to reconstruct hearing.

Evolution of the Reactor Antineutrino Flux and Spectrum at Daya Bay

The Daya Bay experiment has observed correlations between reactor core fuel evolution and changes in the reactor antineutrino flux and energy spectrum. Four antineutrino detectors in two experimental halls were used to identify 2.2 million inverse beta decays (IBDs) over 1230 days spanning multiple fuel cycles for each of six 2.9 GW_{th} reactor cores at the Daya Bay and Ling Ao nuclear power plants. Using detector data spanning effective ^{239}Pu fission fractions F_{239} from 0.25 to 0.35, Daya Bay measures an average IBD yield σ[over ¯]_{f} of (5.90±0.13)×10^{-43}  cm^{2}/fission and a fuel-dependent variation in the IBD yield, dσ_{f}/dF_{239}, of (-1.86±0.18)×10^{-43}  cm^{2}/fission. This observation rejects the hypothesis of a constant antineutrino flux as a function of the ^{239}Pu fission fraction at 10 standard deviations. The variation in IBD yield is found to be energy dependent, rejecting the hypothesis of a constant antineutrino energy spectrum at 5.1 standard deviations. While measurements of the evolution in the IBD spectrum show general agreement with predictions from recent reactor models, the measured evolution in total IBD yield disagrees with recent predictions at 3.1σ. This discrepancy indicates that an overall deficit in the measured flux with respect to predictions does not result from equal fractional deficits from the primary fission isotopes ^{235}U, ^{239}Pu, ^{238}U, and ^{241}Pu. Based on measured IBD yield variations, yields of (6.17±0.17) and (4.27±0.26)×10^{-43}  cm^{2}/fission have been determined for the two dominant fission parent isotopes ^{235}U and ^{239}Pu. A 7.8% discrepancy between the observed and predicted ^{235}U yields suggests that this isotope may be the primary contributor to the reactor antineutrino anomaly.

[Vibrant soundbridge implantation of congenital atresia of oval window(with summary of nine cases]

Objective:To investigate the surgical effects of round window implantation of vibrant soundbridge(VSB)for patients with congenital oval window atresia.Method:Retrospectively analyze the clinical information of 9 cases of congenital oval window atresia as well as the pre-and post-operative hearing and speech results. Three of them had undergone or attempted the vestibulotomy but obtained poor results. All cases underwent round window implantation of VSB. Result:All patients obtained an improvement of 21-33 dBHL after implantation. In the speech recognition rate test, the average increase of disyllabic words was 62%, and 60% in the sentence test. During the follow-up of 51 months in average, 2 cases had a decline of auditory benefit and finally 1 case regained the improvement after reoperation. Conclusion:Round window implantation can get a fairly good result in congenital oval windows atresia cases.

Limits on Active to Sterile Neutrino Oscillations from Disappearance Searches in the MINOS, Daya Bay, and Bugey-3 Experiments

Searches for a light sterile neutrino have been performed independently by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to probe regions allowed by the Liquid Scintillator Neutrino Detector (LSND) and MiniBooNE experiments in a minimally extended four-neutrino flavor framework. Stringent limits on sin^{2}2θ_{μe} are set over 6 orders of magnitude in the sterile mass-squared splitting Δm_{41}^{2}. The sterile-neutrino mixing phase space allowed by the LSND and MiniBooNE experiments is excluded for Δm_{41}^{2}<0.8  eV^{2} at 95%  CL_{s}.

Improved Search for a Light Sterile Neutrino with the Full Configuration of the Daya Bay Experiment

This Letter reports an improved search for light sterile neutrino mixing in the electron antineutrino disappearance channel with the full configuration of the Daya Bay Reactor Neutrino Experiment. With an additional 404 days of data collected in eight antineutrino detectors, this search benefits from 3.6 times the statistics available to the previous publication, as well as from improvements in energy calibration and background reduction. A relative comparison of the rate and energy spectrum of reactor antineutrinos in the three experimental halls yields no evidence of sterile neutrino mixing in the 2×10^{-4}≲|Δm_{41}^{2}|≲0.3  eV^{2} mass range. The resulting limits on sin^{2}2θ_{14} are improved by approx imately a factor of 2 over previous results and constitute the most stringent constraints to date in the |Δm_{41}^{2}|≲0.2  eV^{2} region.

Measurement of the Reactor Antineutrino Flux and Spectrum at Daya Bay

This Letter reports a measurement of the flux and energy spectrum of electron antineutrinos from six 2.9 GWth nuclear reactors with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls in the Daya Bay experiment. Using 217 days of data, 296 721 and 41 589 inverse β decay (IBD) candidates were detected in the near and far halls, respectively. The measured IBD yield is (1.55±0.04) ×10(-18)  cm(2) GW(-1) day(-1) or (5.92±0.14) ×10(-43)  cm(2) fission(-1). This flux measurement is consistent with previous short-baseline reactor antineutrino experiments and is 0.946±0.022 (0.991±0.023) relative to the flux predicted with the Huber-Mueller (ILL-Vogel) fissile antineutrino model. The measured IBD positron energy spectrum deviates from both spectral predictions by more than 2σ over the full energy range with a local significance of up to ∼4σ between 4-6 MeV. A reactor antineutrino spectrum of IBD reactions is extracted from the measured positron energy spectrum for model-independent predictions.

New measurement of antineutrino oscillation with the full detector configuration at Daya Bay

We report a new measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9×10^{5} GW_{th}  ton days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six ^{241}Am-^{13}C radioactive calibration sources reduced the background by a factor of 2 for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of sin^{2}2θ_{13} and |Δm_{ee}^{2}| were halved as a result of these improvements. An analysis of the relative antineutrino rates and energy spectra between detectors gave sin^{2}2θ_{13}=0.084±0.005 and |Δm_{ee}^{2}|=(2.42±0.11)×10^{-3}  eV^{2} in the three-neutrino framework.

Search for a light sterile neutrino at Daya Bay

A search for light sterile neutrino mixing was performed with the first 217 days of data from the Daya Bay Reactor Antineutrino Experiment. The experiment's unique configuration of multiple baselines from six 2.9 GW(th) nuclear reactors to six antineutrino detectors deployed in two near (effective baselines 512 m and 561 m) and one far (1579 m) underground experimental halls makes it possible to test for oscillations to a fourth (sterile) neutrino in the 10(-3) eV(2)<|Δm(41)(2) |< 0.3 eV(2) range. The relative spectral distortion due to the disappearance of electron antineutrinos was found to be consistent with that of the three-flavor oscillation model. The derived limits on sin(2) 2θ(14) cover the 10(-3) eV(2) ≲ |Δm(41)(2)| ≲ 0.1 eV(2) region, which was largely unexplored.

Overexpression of Wild-Type p53-Induced Phosphatase 1 Confers Poor Prognosis of Patients with Nasopharyngeal Carcinoma

This study aimed to analyze the expression, clinical significance of proto-oncogene in nasopharyngeal carcinoma and the biological effect in its cell line by siRNA targeting wild-type p53-induced phosphatase 1 (Wip1). Immunohistochemistry and western blot were respectively used to analyze Wip1 protein expression in 85 cases of nasopharyngeal cancer and normal tissues to study the relationship between Wip1 expression and clinical factors. Wip1 siRNA was transiently transfected into papillary nasopharyngeal carcinoma cell by liposome-mediated method and was detected by Quantitative real-time RT-PCR (qRT-PCR) and western blot. MTT assay, cell apoptosis, migration and invasion were also conducted as to the influence of the down-regulated expression of Wip1 that might be found on CNE2 cells biological effect. The level of Wip1 protein expression was found to be significantly higher in nasopharyngeal cancer tissue than normal tissues (P <0.05). There were significant differences between Wip1 expression and T stages, lymph node metastasis, clinical stages, tumor differentiation and radiotherapy response (P < 0.05), regardless of age, gender (P > 0.05). Meanwhile, Increased expression of Wip1 was significantly with poor overall survival time by Kaplan-Meier analysis (P < 0.05). Wip1 expression deletion determines independent risk factors for prognosis of patients with nasopharyngeal carcinoma in addition to tumor T stage, clinical stage, histological grade and lymph node metastasis outside by Cox-2 in the regression analysis (P < 0.05). qRT-PCR and Western blot showed that CNE2 cell transfected Wip1 siRNA had a lower relative expressive content than normal cell (P < 0.05). MTT assay, cell apoptosis, cell cycles demonstrated that CNE2 cell transfected Wip1 siRNA had a lower survival fraction, higher cell apoptosis, more percentage of the G0/G1 phases, significant decrease in migration and invasion, and higher P53 and P16 protein expression compared with CNE2 cell untransfected Wip1 siRNA (P < 0.05). Wip1 protein was increased in nasopharyngeal carcinoma, specifically in T stages, lymph node metastasis, clinical stages and tumor differentiation. Wip1 may involved in the biological processes of nasopharyngeal cancer cell proliferation, apoptosis, and migration and invasion by regulation P53 and P16 protein expression.

Spectral measurement of electron antineutrino oscillation amplitude and frequency at Daya Bay

A measurement of the energy dependence of antineutrino disappearance at the Daya Bay reactor neutrino experiment is reported. Electron antineutrinos (ν¯(e)) from six 2.9  GW(th) reactors were detected with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls. Using 217 days of data, 41 589 (203 809 and 92 912) antineutrino candidates were detected in the far hall (near halls). An improved measurement of the oscillation amplitude sin(2)2θ(13)=0.090(-0.009)(+0.008) and the first direct measurement of the ν¯(e) mass-squared difference |Δm(ee)2|=(2.59(-0.20)(+0.19))×10(-3)  eV2 is obtained using the observed ν¯(e) rates and energy spectra in a three-neutrino framework. This value of |Δm(ee)2| is consistent with |Δm(μμ)2| measured by muon neutrino disappearance, supporting the three-flavor oscillation model.

γ-Aminobutyric acid-mediated neurotransmission in cerebellar-hypothalamic circuit attenuates gastric mucosal injury induced by ischemia-reperfusion

BACKGROUND

Excessive greater splanchnic nerve (GSN) activation contributes to the progression of gastric ischemia-reperfusion (GI-R) injury. This study was designed to investigate the protective mechanism of cerebellar fastigial nucleus (FN) stimulation against GI-R injury.

METHODS

The GI-R injury model was induced in rats by clamping the celiac artery for 30 min, and then reperfusion for 30 min, 1, 3, 6, or 24 h, respectively.

KEY RESULTS

Microinjection of L-Glu (3, 6, 12 μg) into the FN dose-dependently attenuated GI-R injury and GSN activity. In addition, there was an enhancement of gastric mucosal blood flow in GI-R rats. Pretreatment with the glutamic acid decarboxylase antagonist into the FN, the GABAA receptor antagonist into the lateral hypothalamic area or lesion of superior cerebellar peduncle all reversed the protective effects of the FN stimulation. Furthermore, the FN stimulation reduced the TUNEL-positive gastric mucosal cell and Bax-positive gastric mucosal cell in GI-R rats.

CONCLUSIONS & INFERENCES

These results indicate that the protective effects of the FN stimulation against GI-R injury may be mediated by attenuation of the excessive GSN activation, gastric mucosal cell apoptosis, and Bax expression in GI-R rats.

Morphological variation of mutant sunflowers (Helianthus annuus) induced by space flight and their genetic background detection by SSR primers

After sunflower seeds were exposed to space conditions, various mutant plants were screened from the descendent plants. The morphological characters of plants changed in flower color from golden to yellow, light yellow, or even to yellowish green. The ligulate petals of the unisexual floret broadened, or became thin, while the short tubular petals of bisexual floret elongated to some extent, or even turned into semi-ligulate petals or ligulate petals, making the phenotype of the whole inflorescence like a chrysanthemum. The shape and thickness of leaves varied in some of these plants. Absolute sterile plants in mutant plants were found to possess neither normal bisexual florets nor unisexual florets, but the "pseudo-floret" only consisted of pieces of shield-like bracts on protuberant floral disc. Thirty-five pairs of simple sequence of repeat primers were used to detect the genetic variation of the plants, and the results showed that only a variation was tested in the mutant plants from 4 primers. The different PCR products obtained were extracted for sequencing and alignment analysis, and the aligned results showed that the DNA sequence changed by deletion, insertion and replacement that occurred at some sites. The results proved the high mutagenic efficacy of space flight, and ways of DNA transformation due to space conditions.

Observation of electron-antineutrino disappearance at Daya Bay

The Daya Bay Reactor Neutrino Experiment has measured a nonzero value for the neutrino mixing angle θ(13) with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43,000 ton-GWth-day live-time exposure in 55 days, 10,416 (80,376) electron-antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R=0.940±0.011(stat.)±0.004(syst.). A rate-only analysis finds sin(2)2θ(13)=0.092±0.016(stat.)±0.005(syst.) in a three-neutrino framework.

EZH2 silencing by RNA interference inhibits proliferation in bladder cancer cell lines

The Enhancer of Zeste homologue2 gene (EZH2) is frequently expressed at high levels in malignant tumours, including bladder cancer. It functions as a transcriptional regulator to the maintenance of cell identity, cell cycle regulation and oncogenesis. In the study, we detected EZH2 expression in bladder cancer tissues. These results showed EZH2 high expression in bladder cancer tissue at level of transcript and protein compared with normal bladder tissue and EZH2 expression correlated positively with tumour stage and grade. Then, we used RNA interference to inhibit EZH2 expression in bladder cancer EJ cell line. Efficient downregulation of EZH2 resulted in significantly decreased cell proliferation in EJ cells and retarded transition of G(1) phase to S phase. Our data suggest that EZH2 is involved in the tumourigenesis of bladder cancer and EZH2 downregulation contributes to inhibiting malignant growth by retarding cell entrance to S phase.

Effects of hydrogen plasma treatment on the electrical and optical properties of ZnO films: identification of hydrogen donors in ZnO

Wurtzite ZnO has many potential applications in optoelectronic devices, and the hydrogenated ZnO exhibits excellent photoelectronic properties compared to undoped ZnO; however, the structure of H-related defects is still unclear. In this article, the effects of hydrogen-plasma treatment and subsequent annealing on the electrical and optical properties of ZnO films were investigated by a combination of Hall measurement, Raman scattering, and photoluminescence. It is found that two types of hydrogen-related defects, namely, the interstitial hydrogen located at the bond-centered (H(BC)) and the hydrogen trapped at a O vacancy (H(O)), are responsible for the n-type background conductivity of ZnO films. Besides introducing two hydrogen-related donor states, the incorporated hydrogen passivates defects at grain boundaries. With increasing annealing temperatures, the unstable H(BC) atoms gradually diffuse out of the ZnO films and part of them are converted into H(O), which gives rise to two anomalous Raman peaks at 275 and 510 cm(-1). These results help to clarify the relationship between the hydrogen-related defects in ZnO described in various studies and the free carriers that are produced by the introduction of hydrogen.

Expression and role of Oct3/4, Nanog and Sox2 in regeneration of rat tracheal epithelium

OBJECTIVES

To explore the role of Oct3/4, Nanog and Sox2 in regeneration of rat tracheal epithelium.

MATERIALS AND METHODS

An ex vivo model of rat tracheal epithelial regeneration using 5-fluorouracil (5-FU) was developed, to induce injury. Expression levels of Oct3/4, Nanog and Sox2 were examined using Western blot analysis, RT-PCR or microscopically observed immunofluorescence, and cell morphological changes were observed using HE staining, during the recovery process.

RESULTS

Oct3/4, Nanog and Sox2 were not detectable in normal tracheal epithelium. After treatment with 5-FU, the normally proliferating tracheal epithelium desquamated and only a few cells in G0 phase of the cell cycle were left on the basement membrane and Oct3/4, Nanog and Sox2 could be observed at this time. Thereafter, the number of Oct3/4-, Nanog- and Sox2-positive cells increased gradually. When the cells differentiated into ciliate cells, mucous cells or basal cells, and restored pseudostratified mucociliary epithelium, the number of Oct3/4-, Nanog- and Sox2-positive cells decreased and gradually disappeared.

CONCLUSIONS

G0 phase cells with resistance to 5-FU damage expressed Oct3/4, Nanog and Sox2. This indicated that these cells were undifferentiated, but had the ability to terminally differentiate into downstream-type cells. They possessed stem cell properties. The results are consistent with Oct3/4, Nanog and Sox2-expressing cells being considered as tracheal stem cells.

Expression and role of Notch signalling in the regeneration of rat tracheal epithelium

OBJECTIVES

This study is to explore the role of Notch signalling during the regeneration of rat tracheal epithelium after injury induced by 5-fluorouracil (5-FU).

MATERIALS AND METHODS

We developed an ex vivo model of rat tracheal epithelial regeneration using 5-FU to induce injury. Expression levels of members of the Notch signalling pathway, ABCG2, CK19, and proliferating cell nuclear antigen (PCNA) were examined by reverse transcription-polymerase chain reaction, Western blot, and immunofluorescence. One group of tracheas were cultured in the medium with a gamma-secretase inhibitor or Jag-1 peptide after 5-FU treatment and another group were pre-treated with the gamma-secretase inhibitor or Jag-1 peptide before 5-FU treatment. The expression changes of ABCG2, CK19, and PCNA were examined by Western blot or immunofluorescence and the morphologic changes were observed by haematoxylin and eosin stain during the recovery process.

RESULTS

Expression levels of Notch3, Jagged1, and Hey1 were increased in rat tracheal epithelial cells after treatment with 5-FU. During injury recovery, disruption of Notch signalling by treatment with the gamma-secretase inhibitor reduced expression of ABCG2 and PCNA, but promoted expression of CK19, while persistent activation of Notch signalling promoted expression of ABCG2 and PCNA, but reduced expression of CK19. Under both conditions, recovery from injury was reduced. However, blocking Notch signalling prior to 5-FU treatment led to the complete blockage of recovery, while activating Notch signalling before 5-FU treatment promoted recovery.

CONCLUSIONS

During tracheal epithelial regeneration, Notch signalling maintains an undifferentiated state and promotes proliferation among a population of tracheal epithelial cells.

Measurements of the continuum R(uds) and R values in e(+)e(-) annihilation in the energy region between 3.650 and 3.872 GeV

We report measurements of the continuum R(uds) near the center-of-mass energy of 3.70 GeV, the R[uds(c)+psi(3770)](s) and the R(had)(s) values in e(+)e(-) annihilation at 68 energy points in the energy region between 3.650 and 3.872 GeV with the BES-II detector at the BEPC Collider. We obtain the R(uds) for the continuum light hadron (containing u, d, and s quarks) production near the DD threshold to be R(uds)=2.141+/-0.025+/-0.085.

Search for invisible decays of eta and eta' in J/psi --> phi eta and phi eta'

Using a data sample of 58 x 10(6) J/psi decays collected with the Beijing Spectrometer II detector at the Beijing Electron Positron Collider, searches for invisible decays of eta and eta' in J/psi to phi eta and phi eta' are performed. The phi signals, which are reconstructed in K+K- final states, are used to tag the eta and eta' decays. No signals are found for the invisible decays of either eta or eta', and upper limits at the 90% confidence level are determined to be 1.65 x 10(-3) for the ratio B(eta-->invisible)/B(eta --> gamma gamma) and 6.69 x 10(-2) for B(eta' --> invisible)/B(eta' --> gammagamma). These are the first searches for eta and eta' decays into invisible final states.

Observation of a broad 1-- resonant structure around 1.5 GeV/c2 in the K+K- mass spectrum in J/psi-->K+K-pi0

A broad peak is observed at low K+K- invariant mass in J/psi-->K+K-pi(0) decays found in a sample of 5.8x10(7) J/psi events collected with the BESII detector. The statistical significance of the broad resonance is much larger than 5sigma. A partial wave analysis shows that the J;{PC} of this structure is 1--. Its pole position is determined to be [1576(-55)(+49)(stat)-91+98(syst)] MeV/c(2)-i/2[818(-23)(+22)(stat)-133+64(syst)] MeV/c(2). These parameters are not compatible with any known meson resonances.

Measurements of the branching fractions for psi(3770)-->D(0)D[over ](0), D+D-, DD[over ], and the resonance parameters of psi(3770) and psi(2S)

We measure the branching fractions for psi(3770)-->D(0)D[over ](0), D+D-, DD[over ], and non-DD[over ] to be (46.7+/-4.7+/-2.3)%, (36.9+/-3.7+/-2.8)%, (83.6+/-7.3+/-4.2)%, and (16.4+/-7.3+/-4.2)%, respectively. The resonance parameters of psi(3770) and psi(2S) are measured to be M_(psi(3770))=3772.2+/-0.7+/-0.3 MeV, Gamma_(psi(3770))(tot)=26.9+/-2.4+/-0.3 MeV, and Gamma_(psi(3770))(ee)=251+/-26+/-11 eV; M_(psi(2S))=3685.5+/-0.0+/-0.3 MeV, Gamma_(psi(2S))(tot)=331+/-58+/-2 keV, and Gamma_(psi(2S))(ee)=2.330+/-0.036+/-0.110 keV. We also measure the light hadron R value to be R(uds)=2.262+/-0.054+/-0.109 in the energy region from 3.660 to 3.872 GeV.

Observation of a near-threshold enhancement in the omega(phi) mass spectrum from the doubly OZI-suppressed decay J/psi-->gamma(omega)phi

An enhancement near threshold is observed in the omega(phi) invariant mass spectrum from the doubly Okubo-Zweig-Iizuka-suppressed decays of J/psi-->gamma(omega)phi, based on a sample of 5.8 x 10(7) J/psi events collected with the BESII detector. A partial wave analysis shows that this enhancement favors JP=0+, and its mass and width are M=1812(+19)(-26)(stat)+/-18(syst) MeV/c2 and Gamma=105+/-20(stat)+/-28(syst) MeV/c2. The product branching fraction is determined to be B(J/psi-->gammaX)B(X-->omega(phi))=[2.61+/-0.27(stat)+/-0.65(syst)]x10(-4).

Differential gene expression profiling in aggressive bladder transitional cell carcinoma compared to the adjacent microscopically normal urothelium by microdissection-SMART cDNA PCR-SSH

Identifying novel and known genes that are differentially expressed in aggressive bladder transitional cell carcinoma (BTCC) has important implications in understanding the biology of bladder tumorigenesis and developing new diagnostic and therapeutic agents. In this study we identified the differential gene expression profiles comparing tumor to the adjacent microscopically normal mucosa by manual microdissection on frozen sections. The RNAs extracted from microdissected tissues were amplified by SMART cDNA PCR technology to generate forward subtractive cDNA library by suppressive subtractive hybridization (SSH). We obtained 376 positive clones, one hundred clones of aggressive BTCC subtracted cDNA library were selected at random and inserts were reamplified by PCR. After differential screening by reverse dot blotting, 73 positive clones, that contend inserts putatively upregulated in aggressive BTCC, were further analysed by DNA sequencing, GenBank and EST database searching. Sequencing results showed that 66 clones stand for 23 known genes and 7 clones for three new EST (Genbank number: DN236875, DN236874 and DN236873). In conclusion, microdissection-SMART cDNA PCR-SSH allowed for an efficient way to identify aggressive BTCC-specific differential expressed genes that may potentially be involved in the carcinogenesis and/or progression of aggressive BTCC. These differentially expressed genes may be of potential utility as therapeutic and diagnostic targets for aggressive BTCC.

Observation of a resonance in Chi(1835) in J/psi --> gammapi+ pi- eta-

The decay channel J/psi --> gamma(pi)(+)pi(-)eta is analyzed using a sample of 5.8 x 10(7) J/psi events collected with the BESII detector. A resonance, the Chi(1835), is observed in the pi(+)pi(-)eta invariant-mass spectrum with a statistical significance of 7.7 sigma. A fit with a Breit-Wigner function yields a mass M = 1833.7 +/- 6.1(stat) +/- 2.7(syst) MeV/c(2), a width Tau = 67.7 +/- 20.3(stat) +/- 7.7(syst) MeV/c(2), and a product branching fraction B(J/psi --> gammaChi) . B(Chi --> pi(+)pi(-)eta) = [2.2 +/- 0.4(stat) +/- 0.4(syst)] x 10(-4). The mass and width of the Chi(1835) are not compatible with any known meson resonance. Its properties are consistent with expectations for the state that produces the strong pp mass threshold enhancement observed in the J/psi --> gammapp process at BESII.

Superior extension of the parascapular free flap for cervical burn scar contracture

A newly designed superior extension of the parascapular free flap and its free transfer clinically for the repair of 11 cases of cervical burn scar contracture without any loss are presented. The flap sizes ranged from 16 x 7 cm to 32 x 11 cm. Based on the anatomic distribution of the circumflex scapular vessels, the flap in the scapular territory can be taken much longer and wider than before. There is less tension in this vertically oriented flap than in the horizontally oriented flap in obtaining primary closure. This method extends the application of the scapular territory as a donor site for free flaps.