[Techniques for quantifying endotypes of obstructive sleep apnea]

Obstructive sleep apnea (OSA) is the frequent occurrence of apnea and/or hypopnea during sleep, leading to intermittent hypoxia, hypercapnia, and disruption of sleep architecture, further resulting in multisystem damage. The pathophysiological mechanisms include abnormal anatomical structure, low arousal threshold, high loop gain, and poor muscle reactivity, etc. As there are individual differences in the underlying mechanisms of OSA (i.e. endotypes), the effectiveness of treatment and prognosis may also vary according to these characteristics. Understanding the endotype of OSA is critical to understanding which patients are most likely to benefit from non-invasive ventilation therapy. Quantification of endotypes is central to the precision treatment of OSA and may provide the basis for accurate clinical treatment of OSA based on endotypes.

Occupancy of orbitals and the quadrupole collectivity in 45Sc nucleus

In the present work, the Doppler Shift Attenuation method (DSAM) was used to analyze the observed lineshapes of transitions from excited states in ⁴⁵Sc, populated in the reaction ³⁶Ar + ¹²C at a beam energy of 145 MeV. The interpretation and comparison of the experimental results have been performed with large-scale shell model calculations, involving different interactions like: GX1A, GX1J, FPD6, KB3 and ZBM2. KB3 and FPD6 (present work) interactions in the negative parity states, and in positive parity states ZBM2 are most pre-eminent in reproducing the results, due to the large configuration space describing strong collective effects. Furthermore, the present work also looks at the details of the shell model helping in improving the understanding for the occupancy of orbitals. The present investigation suggests the observation of stronger collectivity for positive parity states over negative parity states with predicted enhanced collectivity of states in ⁴⁵Sc nucleus.

[Research advances on the mechanism of oral mucosal stem cells in promoting wound healing]

Wound healing is a complex process that requires the participation of multiple cells and cytokines. During the process of wound healing, abnormality in any stage of the process may lead to the development of a chronic refractory wound. Research has confirmed that various stem cells can promote wound healing, but some stem cells are limited in clinical application due to difficulties in isolation, susceptibility to apoptosis, ethical and legal issues. Oral mucosal stem cells (OMSCs) can avoid the above problems. This type of stem cells has the characteristics of embryonic stem cells, immune regulatory ability, and strong homogeneity. It plays an important role in the process of scarless oral wound healing, and has become a research hotspot in promoting wound healing and reducing scar formation. This article reviews the research on the mechanism, clinical application prospects, and current problems of OMSCs in promoting wound healing.

Probing ^{93m}Mo Isomer Depletion with an Isomer Beam

The isomer depletion of ^{93m}Mo was recently reported [Chiara et al., Nature (London) 554, 216 (2018)NATUAS0028-083610.1038/nature25483] as the first direct observation of nuclear excitation by electron capture (NEEC). However, the measured excitation probability of 1.0(3)% is far beyond the theoretical expectation. In order to understand the inconsistency between theory and experiment, we produce the ^{93m}Mo nuclei using the ^{12}C(^{86}Kr,5n) reaction at a beam energy of 559 MeV and transport the reaction residues to a detection station far away from the target area employing a secondary beam line. The isomer depletion is expected to occur during the slowdown process of the ions in the stopping material. In such a low γ-ray background environment, the signature of isomer depletion is not observed, and an upper limit of 2×10^{-5} is estimated for the excitation probability. This is consistent with the theoretical expectation. Our findings shed doubt on the previously reported NEEC phenomenon and highlight the necessity and feasibility of further experimental investigations for reexamining the isomer depletion under low γ-ray background.

[Role and mechanism of Vγ4 T cells in impaired wound healing of rapamycin-induced full-thickness skin defects in mice]

Objective: To investigate the role and mechanism of Vγ4 T cells in impaired wound healing of rapamycin-induced full-thickness skin defects in mice. Methods: The experimental research methods were applied. Eighty-six C57BL/6J male mice (hereinafter briefly referred to as wild-type mice) aged 8-12 weeks were selected for the following experiments. Vγ4 T cells were isolated from axillary lymph nodes of five wild-type mice for the following experiments. Intraperitoneal injection of rapamycin for 42 mice was performed to establish rapamycin-treated mice model for the following experiments. Eighteen wild-type mice were divided into normal control group without any treatment, trauma only group, and trauma+CC chemokine ligand 20 (CCL20) inhibitor group according to the random number table (the same grouping method below), with 6 mice in each group. The full-thickness skin defect wound was made on the back of mice in the latter two groups (the same wound model below), and mice in trauma+CCL20 inhibitor group were continuously injected subcutaneously with CCL20 inhibitor at the wound edge for 3 days after injury. Another 6 rapamycin-treated mice were used to establish wound model as rapamycin+trauma group. On post injury day (PID) 3, the epidermal cells of the skin tissue around the wound of each trauma mice were extracted by enzyme digestion, and the percentage of Vγ4 T cells in the epidermal cells was detected by flow cytometry. In normal control group, the epidermal cells of the normal skin tissue in the back of mice were taken at the appropriate time point for detection as above. Five wild-type mice were used to establish wound models. On PID 3, the epidermal cells were extracted from the skin tissue around the wound. The cell populations were divided into Vγ4 T cells, Vγ3 T cells, and γδ negative cells by fluorescence-activated cell sorter, which were set as Vγ4 T cell group, Vγ3 T cell group, and γδ negative cell group (with cells in each group being mixed with B16 mouse melanoma cells), respectively. B16 mouse melanoma cells were used as melanoma cell control group. The expression of interleukin-22 (IL-22) mRNA in cells of each group was detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR), with the number of samples being 6. Thirty rapamycin-treated mice were used to establish wound models, which were divided into Vγ4 T cell only group and Vγ4 T cell+IL-22 inhibitor group performed with corresponding injections and rapamycin control group injected with phosphate buffer solution (PBS) immediately after injury, with 10 mice in each group. Another 10 wild-type mice were taken to establish wound models and injected with PBS as wild-type control group. Mice in each group were injected continuously for 6 days. The percentage of wound area of mice in the four groups was calculated on PID 1, 2, 3, 4, 5, and 6 after injection on the same day. Six wild-type mice and 6 rapamycin-treated mice were taken respectively to establish wound models as wild-type group and rapamycin group. On PID 3, the mRNA and protein expressions of IL-22 and CCL20 in the peri-wound epidermis tissue of mice in the two groups were detected by real-time fluorescence quantitative RT-PCR and Western blotting, respectively. The Vγ4 T cells were divided into normal control group without any treatment and rapamycin-treated rapamycin group. After being cultured for 24 hours, the mRNA and protein expressions of IL-22 of cells in the two groups were detected by real-time fluorescence quantitative RT-PCR and Western blotting, respectively, with the number of samples being 6. Data were statistically analyzed with independent sample t test, analysis of variance for repeated measurement, one-way analysis of variance, Bonferroni method, Kruskal-Wallis H test, and Wilcoxon rank sum test. Results: The percentage of Vγ4 T cells in the epidermal cells of the skin tissue around the wound of mice in trauma only group on PID 3 was 0.66% (0.52%, 0.81%), which was significantly higher than 0.09% (0.04%, 0.14%) in the epidermal cells of the normal skin tissue of mice in normal control group (Z=4.31, P<0.01). The percentages of Vγ4 T cells in the epidermal cells of the skin tissue around the wound of mice in rapamycin+trauma group and trauma+CCL20 inhibitor group on PID 3 were 0.25% (0.16%, 0.37%) and 0.24% (0.17%, 0.35%), respectively, which were significantly lower than that in trauma only group (with Z values of 2.27 and 2.25, respectively, P<0.05). The mRNA expression level of IL-22 of cells in Vγ4 T cell group was significantly higher than that in Vγ3 T cell group, γδ negative cell group, and melanoma cell control group (with Z values of 2.96, 2.45, and 3.41, respectively, P<0.05 or P<0.01). Compared with that in wild-type control group, the percentage of wound area of mice in rapamycin control group increased significantly on PID 1-6 (P<0.01), the percentage of wound area of mice in Vγ4 T cell+IL-22 inhibitor group increased significantly on PID 1 and PID 3-6 (P<0.05 or P<0.01). Compared with that in rapamycin control group, the percentage of wound area of mice in Vγ4 T cell only group decreased significantly on PID 1-6 (P<0.05 or P<0.01). Compared with that in Vγ4 T cell only group, the percentage of wound area of mice in Vγ4 T cell+IL-22 inhibitor group increased significantly on PID 3-6 (P<0.05 or P<0.01). On PID 3, compared with those in wild-type group, the expression levels of IL-22 protein and mRNA (with t values of -7.82 and -5.04, respectively, P<0.01) and CCL20 protein and mRNA (with t values of -7.12 and -5.73, respectively, P<0.01) were decreased significantly in the peri-wound epidermis tissue of mice in rapamycin group. After being cultured for 24 hours, the expression levels of IL-22 protein and mRNA in Vγ4 T cells in rapamycin group were significantly lower than those in normal control group (with t values of -7.75 and -6.04, respectively, P<0.01). Conclusions: In mice with full-thickness skin defects, rapamycin may impair the CCL20 chemotactic system by inhibiting the expression of CCL20, leading to a decrease in the recruitment of Vγ4 T cells to the epidermis, and at the same time inhibit the secretion of IL-22 by Vγ4 T cells, thereby slowing the wound healing rate.

[Prevalence of hyperkalemia and its effects on mortality in hospitalized patients: a single center 10-year retrospective analysis]

Objective: To investigate the prevalence of hyperkalemia in hospitalized patients, and analyze the effects of different serum potassium levels and change rates of serum potassium on the mortality of hospitalized patients. Methods: The clinical data of 944 446 hospitalized patients in Sichuan Provincial People's Hospital from January 2009 to December 2018 were retrospectively analyzed. Hyperkalemia is defined as serum potassium ≥ 5.5 mmol/L. The effects of serum potassium level and its change rate on hospitalized mortality were analyzed. Results: There were 15 771 patients with hyperkalemia, and the prevalence of hyperkalemia was 1.7% (15 771/944 446). However, the discharge diagnosis rate was only 11.0% (1 735/15 771), and the missed diagnosis rate was 89.0% (14 036/15 771). Cox regression analysis showed that serum potassium<3.5 mmol/L (HR=1.338, 95%CI: 1.164-1.537, P<0.001) or ≥ 6.5 mmol/L (HR=1.421, 95%CI: 1.158-1.744, P=0.001) increased the risk of hospitalized mortality compared with patients with normal serum potassium. Compared with the increased rate of serum potassium by 0.01-0.10 mmol/d, patients who reached the peak of serum potassium at admission (HR=1.251, 95%CI: 1.077-1.453, P=0.003), increased rate of serum potassium by 0.11-0.51 mmol/d (HR=1.499, 95%CI: 1.315-1.709, P<0.001) or >0.51 mmol/d (HR=2.431, 95%CI: 2.105-2.807, P<0.001) increased the risk of mortality. Of patients with hyperkalemia, those who did not repeat the serum potassium test had a higher risk of mortality (HR=1.656, 95%CI: 1.434-1.914, P<0.001). Conclusions: The prevalence of hyperkalemia in hospitalized patients was 1.7%, and the missed diagnosis rate was high at discharge. Patients who had hypokalemia at admission, severe hyperkalemia, rapid increased serum potassium, or failed to repeat serum potassium test during hospitalization, had higher risk of mortality.

New α-Emitting Isotope ^{214}U and Abnormal Enhancement of α-Particle Clustering in Lightest Uranium Isotopes

A new α-emitting isotope ^{214}U, produced by the fusion-evaporation reaction ^{182}W(^{36}Ar,4n)^{214}U, was identified by employing the gas-filled recoil separator SHANS and the recoil-α correlation technique. More precise α-decay properties of even-even nuclei ^{216,218}U were also measured in the reactions of ^{40}Ar, ^{40}Ca beams with ^{180,182,184}W targets. By combining the experimental data, improved α-decay reduced widths δ^{2} for the even-even Po-Pu nuclei in the vicinity of the magic neutron number N=126 are deduced. Their systematic trends are discussed in terms of the N_{p}N_{n} scheme in order to study the influence of proton-neutron interaction on α decay in this region of nuclei. It is strikingly found that the reduced widths of ^{214,216}U are significantly enhanced by a factor of two as compared with the N_{p}N_{n} systematics for the 84≤Z≤90 and N<126 even-even nuclei. The abnormal enhancement is interpreted by the strong monopole interaction between the valence protons and neutrons occupying the π1f_{7/2} and ν1f_{5/2} spin-orbit partner orbits, which is supported by the large-scale shell model calculation.

Application of random sample consensus method for parameter estimation of reflectometry density profile in toroidal plasma

Microwave reflectometry diagnostics have been widely used to measure density profiles in fusion plasma. However, the high sensitivity of the diagnostics to plasma turbulence often results in large radial deviations in the edge density profile and causes difficulty in profile evaluation. To improve the performance of profile evaluation, a modified RANdom SAmple Consensus (RANSAC) method has been applied to fit the density profiles measured by reflectometry on the experimental advanced superconducting tokamak. Compared with the traditional least-squares method, the modified RANSAC method is much more efficient and robust in fitting the experimental profiles. Furthermore, a combination of RANSAC and a genetic algorithm (GA-RANSAC) is used to further optimize the profile evaluation procedure. The results show that this GA-RANSAC method yields better performance and stabler convergence than the modified RANSAC alone.

[Development of a hyperkalemia risk assessment model for patients with chronic kidney disease]

Objective: To investigate risk factors for hyperkalemia among chronic kidney disease (CKD) patients and establish a risk assessment model for predicting hyperkalemia events. Methods: Clinical data of CKD patients (stage 3 to 5) hospitalized between May 2017 and June 2020 from 14 hospitals were retrospectively collected and divided into training dataset and validation dataset through balanced random sampling. Multivariate logistic regression analysis was used to analyze risk factors for hyperkalemia in CKD patients and the factors were scored. Receiver operating characteristic (ROC) curve was plotted and the area under the curve (AUC) was calculated. Meanwhile, the cut-off value with the best sensitivity and specificity were used to verify the accuracy of the model in validation dataset. Results: A total of 847 CKD patients were enrolled and further divided into training dataset (n=675) and validation dataset (n=172). There were 555 males and 292 females, with a mean age of (57.2±15.6) years. Multivariate logistic regression analysis showed that age, CKD stage, history of heart failure, history of serum potassium ≥5.0 mmol/L, diabetes, metabolic acidosis, and use of medications that increase serum potassium levels were risk factors for causing hyperkalemia in patients with CKD. Risk assessment model was established based on these risk factors. The AUC of the ROC curve was 0.809. Using 4 as the cut-off value, the sensitivity and specificity for predicting hyperkalemia events reached 87.1% and 57.0%, respectively. Conclusion: The model established in the current study can be used for predicting hyperkalemia events in clinical practices, which offers a new way to optimize serum potassium management in patients with CKD.

Measurement of the Spectral Shape of the β-Decay of ^{137}Xe to the Ground State of ^{137}Cs in EXO-200 and Comparison with Theory

We report on a comparison between the theoretically predicted and experimentally measured spectra of the first-forbidden nonunique β-decay transition ^{137}Xe(7/2^{-})→^{137}Cs(7/2^{+}). The experimental data were acquired by the EXO-200 experiment during a deployment of an AmBe neutron source. The ultralow background environment of EXO-200, together with dedicated source deployment and analysis procedures, allowed for collection of a pure sample of the decays, with an estimated signal to background ratio of more than 99 to 1 in the energy range from 1075 to 4175 keV. In addition to providing a rare and accurate measurement of the first-forbidden nonunique β-decay shape, this work constitutes a novel test of the calculated electron spectral shapes in the context of the reactor antineutrino anomaly and spectral bump.

Search for Neutrinoless Double-β Decay with the Complete EXO-200 Dataset

A search for neutrinoless double-β decay (0νββ) in ^{136}Xe is performed with the full EXO-200 dataset using a deep neural network to discriminate between 0νββ and background events. Relative to previous analyses, the signal detection efficiency has been raised from 80.8% to 96.4±3.0%, and the energy resolution of the detector at the Q value of ^{136}Xe 0νββ has been improved from σ/E=1.23% to 1.15±0.02% with the upgraded detector. Accounting for the new data, the median 90% confidence level 0νββ half-life sensitivity for this analysis is 5.0×10^{25}  yr with a total ^{136}Xe exposure of 234.1 kg yr. No statistically significant evidence for 0νββ is observed, leading to a lower limit on the 0νββ half-life of 3.5×10^{25}  yr at the 90% confidence level.

Development of an ordinary mode multi-channel correlation reflectometer on EAST tokamak

An ordinary-mode polarized multi-channel correlation reflectometer has been developed on the Experimental Advanced Superconducting Tokamak (EAST). The system with four different probing frequencies (i.e., 20.4 GHz, 24.8 GHz, 33 GHz, and 40 GHz) and two poloidally spaced receiving antennas can realize both the radial correlation measurement and the poloidal correlation measurement. These diagnostics focus on the measurement of density fluctuation in the pedestal region to investigate the turbulence transport and H-mode physics on EAST. In this article, the system hardware design, the key component tests, and the system performance are shown in detail.

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.

Preliminary consideration of CFETR ITER-like case diagnostic system

Chinese Fusion Engineering Test Reactor (CFETR) is a new superconducting tokamak device being designed in China, which aims at bridging the gap between ITER and DEMO, where DEMO is a tokamak demonstration fusion reactor. Two diagnostic cases, ITER-like case and towards DEMO case, have been considered for CFETR early and later operating phases, respectively. In this paper, some preliminary consideration of ITER-like case will be presented. Based on ITER diagnostic system, three versions of increased complexity and coverage of the ITER-like case diagnostic system have been developed with different goals and functions. Version A aims only machine protection and basic control. Both of version B and version C are mainly for machine protection, basic and advanced control, but version C has an increased level of redundancy necessary for improved measurements capability. The performance of these versions and needed R&D work are outlined.

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.

[A new kinematics method of determing elbow rotation axis and evaluation of its feasibility]

OBJECTIVE

To study a new positioning method of elbow external fixation rotation axis, and to evaluate its feasibility.

METHODS

Four normal adult volunteers and six Sawbone elbow models were brought into this experiment. The kinematic data of five elbow flexion were collected respectively by optical positioning system. The rotation axes of the elbow joints were fitted by the least square method. The kinematic data and fitting results were visually displayed. According to the fitting results, the average moving planes and rotation axes were calculated. Thus, the rotation axes of new kinematic methods were obtained. By using standard clinical methods, the entrance and exit points of rotation axes of six Sawbone elbow models were located under X-ray. And The kirschner wires were placed as the representatives of rotation axes using traditional positioning methods. Then, the entrance point deviation, the exit point deviation and the angle deviation of two kinds of located rotation axes were compared.

RESULTS

As to the four volunteers, the indicators represented circular degree and coplanarity of elbow flexion movement trajectory of each volunteer were both about 1 mm. All the distance deviations of the moving axes to the average moving rotation axes of the five volunteers were less than 3 mm. All the angle deviations of the moving axes to the average moving rotation axes of the five volunteers were less than 5°. As to the six Sawbone models, the average entrance point deviations, the average exit point deviations and the average angle deviations of two different rotation axes determined by two kinds of located methods were respectively 1.697 2 mm, 1.838 3 mm and 1.321 7°. All the deviations were very small. They were all in an acceptable range of clinical practice.

CONCLUSION

The values that represent circular degree and coplanarity of volunteer's elbow single curvature movement trajectory are very small. The result shows that the elbow single curvature movement can be regarded as the approximate fixed axis movement. The new method can replace the traditional method in accuracy. It can make up the deficiency of the traditional fixed axis method.

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.

Design of vibration compensation interferometer for Experimental Advanced Superconducting Tokamak

A vibration compensation interferometer (wavelength at 0.532 μm) has been designed and tested for Experimental Advanced Superconducting Tokamak (EAST). It is designed as a sub-system for EAST far-infrared (wavelength at 432.5 μm) poloarimeter/interferometer system. Two Acoustic Optical Modulators have been applied to produce the 1 MHz intermediate frequency. The path length drift of the system is lower than 2 wavelengths within 10 min test, showing the system stability. The system sensitivity has been tested by applying a periodic vibration source on one mirror in the system. The vibration is measured and the result matches the source period. The system is expected to be installed on EAST by the end of 2014.

Optical layout and mechanical structure of polarimeter-interferometer system for Experimental Advanced Superconducting Tokamak

A Far-InfaRed (FIR) three-wave POlarimeter-INTerferometer (POINT) system for measurement current density profile and electron density profile is under development for the EAST tokamak. The FIR beams are transmitted from the laser room to the optical tower adjacent to EAST via ∼20 m overmoded dielectric waveguide and then divided into 5 horizontal chords. The optical arrangement was designed using ZEMAX, which provides information on the beam spot size and energy distribution throughout the optical system. ZEMAX calculations used to optimize the optical layout design are combined with the mechanical design from CATIA, providing a 3D visualization of the entire POINT system.

Faraday-effect polarimeter-interferometer system for current density measurement on EAST

A multichannel far-infrared laser-based POlarimeter-INTerferometer (POINT) system utilizing the three-wave technique is under development for current density and electron density profile measurements in the EAST tokamak. Novel molybdenum retro-reflectors are mounted in the inside wall for the double-pass optical arrangement. A Digital Phase Detector with 250 kHz bandwidth, which will provide real-time Faraday rotation angle and density phase shift output, have been developed for use on the POINT system. Initial calibration indicates the electron line-integrated density resolution is less than 5 × 10(16) m(-2) (∼2°), and the Faraday rotation angle rms phase noise is <0.1°.

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.

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.

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.

Comparison of rate control and rhythm control in patients with atrial fibrillation after percutaneous mitral balloon valvotomy: a randomised controlled study

OBJECTIVE

To compare rate control and rhythm control strategies in patients with atrial fibrillation (AF) after percutaneous mitral balloon valvotomy (PMV).

METHODS

183 patients with AF after successful PMV, with AF duration <or= 12 months and post-PMV left atrial (LA) size <or= 45 mm, were studied in a prospective, randomised trial. The primary end point was improvement in AF-related symptoms. Secondary study end points were 6 min walk tests, quality of life (QOL), normalisation of LA size, number of hospital admissions and duration of hospital stay.

RESULTS

Over one year, 2% patients in the rate control group had sinus rhythm, as compared with 96% of patients in the rhythm control group (p < 0.001). A greater proportion of patients reported improvement in symptoms in the rhythm control group than in the rate control group (p < 0.0001 at every visit time). Walking distance in a 6 min walk test, QOL and LA size normalisation were better in the rhythm control group than in the rate control group. The strategy of rhythm control was associated with similar numbers of hospital admissions but with longer duration of hospital admissions. Drug-related side effect did not differ between the rate control and rhythm control groups. During the follow-up period, no patients in either group had embolic or transitory ischaemic neurological events.

CONCLUSIONS

In patients with AF after PMV, AF duration <or= 12 months and post-PMV LA size <or= 45 mm, sinus rhythm was easy and safe to achieve and maintain. Moreover, patients benefited from restoration and maintenance of sinus rhythm in terms of improved AF-related symptoms, 6 min walk tests and QOL, and of LA size normalisation. Rhythm control should therefore be considered as the preferred initial therapy for this group of patients. The optimal strategy to treat AF after PMV should be individualised.

Temperature trends in total hip arthroplasty: a retrospective study

The purpose of this study was to define the temporal trend in body temperature of patients during the first 5 days after total hip arthroplasty (THA). The medical records of 98 consecutive THAs were reviewed, 88 clinically uncomplicated cases were included. The average maximum temperature reached during the study period was 38.08 degrees C, a 3.7% (P< or =.01) increase from the preoperative base line of 36.64 degrees C. In this study, 62.5% of patients reached a temperature > or =38.0 degrees C; 19.3% > or = 38.5 degrees C; and 3.4% > or = 39.0 degrees C. No patients had a preoperative temperature of > or =38 degrees C recorded. On the first postoperative day, 39 patients had a temperature > or =38 degrees C. The number of febrile patients progressively decreased until by the fifth postoperative day, only 5 patients had a temperature > or =38 degrees C recorded.

[Effect of allitridi on expression of proliferating cell nuclear antigen of cultured rabbit aortic smooth muscle cell]

OBJECTIVE

To observe the effect of allitridi on the expression of proliferating cell nuclear antigen (PCNA) of cultured rabbit aortic smooth muscle cell (SMC).

METHODS

The expression of PCNA was examined with immunohistochemical technique (LSAB method) and the contents of superoxide dismutase (SOD), lipid peroxide (LPO), prostacyclin (PGI2) and cyclic adenosine monophosphate (cAMP) in medium were simultaneously determined.

RESULTS

Allitridi has the effects of increasing SOD activity, decreasing LPO, elevating PGI2 and cAMP, reducing the expression of PCNA (all P < 0.05-0.01).

CONCLUSION

Allitridi could inhibit SMC proliferation.

Effect of repetitive bleeding on NADH-cytochrome b5 methemoglobin reductase activity and molybdenum content in erythrocytes in rats

Reticulocytosis in rats was induced by repetitive bleeding. Both in the vitro and the in vivo studies showed that the detected reductive speed of methemoglobin of the bleeding group was faster than that of the control group at all time intervals. At the same time, the NADH-cytochrome b5 methemoglobin reductase activity and the molybdenum content in erythrocytes of the bleeding group were significantly increased. Regressional analysis showed that there was a significantly positive correlation between the enzyme activity and the molybdenum content. It is proposed that molybdenum might be required for the enzyme activity.

Myocardial protection of cold crystalloid and warm blood cardioplegia. A comparative study

Twenty patients undergoing open-heart valvular operations were divided randomly into two groups. Intermittent perfusion of cold crystalloid (St. Thomas Hospital solution) with hypothermic cardiopulmonary bypass (CPB) in the hypothermic group and continuous administration of warm blood cardioplegia with normothermic CPB in the normothermic group were used respectively. The results of warm blood cardioplegia were superior to those of cold crystalloid. 70% of patients treated with the warm technique had spontaneous return of normal sinus rhythm shortly after removal of the aortic cross-clamp, compared with only 10% of the hypothermic group (P < 0.05). The extracorporeal support time from releasing of aortic clamp to the weaning of CPB was significantly shorter in the normothermic group (33.50 +/- 3.78 min vs. 25.00 +/- 4.64 min, P < 0.05). The postoperative ventilation support time was also much shorter than that of the hypothermic group (19.84 +/- 1.11 h vs. 38.98 +/- 16.55 h, P < 0.05). More atrial beating occurred in the normothermic group (80% vs. 20%, P < 0.05) during aortic clamping, and it is showed that continuous warm blood cardioplegia might not efficiently prevent the atrium from damage.

[An improved technique for bloodless hepatic resection on the in situ cold perfused liver]

An improved technique for bloodless hepatic resection using in vivo isolation and asanguinous hypothermic perfusion was described to deal with the huge liver tumour involving the liver hilum, the main hepatic veins and retrohepatic inferior vena cava. The original Fortner's technique was modified, including the incision; isolated cold perfusion of the healthy half of the liver through the portal vein; suprahepatic outlet for the perfusate, and shortened hepatic ischemia time by perfusing hepatic artery prior to the repair or reconstruction of the portal vein. Using this technique, two huge liver tumors were successfully resected, and the indications, intraoperative monitoring and early postoperative courses were discussed.

[Studies on cultivation techniques for Rehmannia glutinosa Libosch. in summer]

Through many years' research, a set of cultivation techniques for Rehmannia glutinosa in summer has been found out as "selecting necks in autumn; growing seedlings with plastic films in early spring; culturing around summer solstice and reaping after autumn". A Study has also been made on the scope feasible for spreading the application of these techniques.

An improved technique for bloodless hepatic resection on in situ cold perfused liver

An improved technique for bloodless hepatic resection using in situ isolation and asanguinous hypothermic perfusion was described to deal with huge liver tumors involved in the liver hilum, the main hepatic veins and retrohepatic inferior vena cava. The original Fortner's technique was modified, including the choice of incision; semi-isolated perfusion of the liver portion preserved through the single portal vein; suprahepatic outlet of the perfusate and the shortening of the period of hepatic ischemia by reperfusion of hepatic artery prior to the repair or reconstruction of the portal vein. The initial successful experience of the technique applied to 2 pediatric cases with giant liver tumors was reported, and the indications, intraoperative and early postoperative courses were discussed.

Further investigation on nuclear transplantation in different orders of teleost: the combination of the nucleus of Tilapia (Oreochromis nilotica) and the cytoplasm of Loach (Paramisgurnus dabryanus)

The nucleus of a blastula cell from Tilapia (Oreochromis nilotica, family Cichlidae, order Perciformes) was transplanted into an enucleated egg of Loach (Paramisgurnus dabryanus, family Cobitidae, order Cypriniformes). From among 3747 nucleo-cytoplasmic hybrid (NCH) eggs two NCH larval fish (0.05%) were obtained; one died on the 6th day and the other died on the 12th day after the operation. Morphological examinations showed that both NCH larval fish had developed normally with an opened mouth except they could not take food after complete utilization of their egg yolk on the 5th day of development. The possible mechanisms for obtaining such inter-order NCH larval fish are discussed. This is the first report indicating that inter-order NCH larval fish can be obtained in spite of their evolutionary divergence.

Developmental incompatibility between cell nucleus and cytoplasm as revealed by nuclear transplantation experiments in teleost of different families and orders

Teleosts from different families and orders were used as materials for nuclear transplantation experiments. (1) The nuclei of goldfish (Carassius auratus, family Cyprinidae, order Cypriniformes) were transplanted into the enucleated egg cytoplasm of loach (Paramisgurnus dabryanus, family Cobitidae, order Cypriniformes) and vice-versa. (2) The nuclei of Tilapia (oreochromis nilotica, order Perciformes) were transplanted into the enucleated egg cytoplasm of goldfish (Carassius auratus, order Cypriniformes). The chromosome number of the nucleus donor fish is different from that of the cytoplasmic recipient fish in each of the two combinations. In the first case, only a few early nucleo-cytoplasmic hybrid (NCH) larval fish were obtained in each combination. In second case, even though a high percentage of NCH blastulas were also obtained, the majority of them died at the same developmental stage, except a few which survived until early gastrula stage. The examination of the metaphase chromosome figures of the NCH blastulas or embryos obtained in all three combinations indicated that they were of nucleus-donor type. The developmental rates of all the NCH eggs were similar to those of cytoplasmic-recipient type. Scanning electronmicroscopy examination showed that the morphology of NCH blastula cells, which were obtained from the combination of Tilapia nucleus and goldfish cytoplasm, manifested obviously abnormal features and the cells were arrested at different stages of cell disintegration. Two-dimension polyacrylamide gel electrophoretograms of the homogenates of Tilapia, goldfish and their NCH blastula cells showed that the protein synthetic pattern of NCH blastula was similar to that of Tilapia nucleus type. The results of experiments which failed to obtain NCH adult fish in all three combinations can be explained as a result of developmental incompatibility between the donor nucleus and the enucleated recipient egg cytoplasm, which were from distantly related fish species. And the chromosome numbers of all the component fish of the three combinations which were examined in the experiment and shown to be quite different from each other in the tested fish, should not be overlooked as one of the essential factors causing the developmental incompatibility in NCH fish in this experiment.

A new bilirubin-degrading enzyme from orange peels

A novel enzyme activity that catalyzes the degradation of unconjugated bilirubin (Bu) has been demonstrated in extracts of the peels of edible oranges. Unlike the few known bilirubin-oxidizing enzymes, the orange enzyme does not produce biliverdin as a product, does not seem to require oxygen, and has a unique absorption spectrum of its products. Even at the crude stage, the enzyme has a specific activity that is 10 and 20 times higher, respectively, than those reported for the crude or partially purified Bu-degrading enzymes from mushrooms and rat liver. The enzyme has a pH optimum near 7.5 and a Km value of 50-100 microM for Bu. The enzyme is remarkably stable, retaining over 50% activity after prolonged digestion with proteinase K or heating at 100 degrees C. Similar treatments inactivated the bilirubin oxidase from Myrothecium verrucaria MT-1. The enzyme is poorly soluble in water but can be partially solubilized with cholic acid, with a doubling in specific activity.