Experimental Limits on Solar Reflected Dark Matter with a New Approach on Accelerated-Dark-Matter-Electron Analysis in Semiconductors.

Recently a dark matter-electron (DM-electron) paradigm has drawn much attention. Models beyond the standard halo model describing DM accelerated by high energy celestial bodies are under intense examination as well. In this Letter, a velocity components analysis (VCA) method dedicated to swift analysis of accelerated DM-electron interactions via semiconductor detectors is proposed and the first HPGe detector-based accelerated DM-electron analysis is realized. Utilizing the method, the first germanium based constraint on sub-GeV solar reflected DM-electron interaction is presented with the 205.4 kg·day dataset from the CDEX-10 experiment. In the heavy mediator scenario, our result excels in the mass range of 5-15 keV/c^{2}, achieving a 3 orders of magnitude improvement comparing with previous semiconductor experiments. In the light mediator scenario, the strongest laboratory constraint for DM lighter than 0.1 MeV/c^{2} is presented. The result proves the feasibility and demonstrates the vast potential of the VCA technique in future accelerated DM-electron analyses with semiconductor detectors.

[Deubiquitinating enzyme MINDY1 is an independent risk factor for the maintenance of stemness and poor prognosis in liver cancer cells].

Objective: To explore the key deubiquitinating enzymes that maintain the stemness of liver cancer stem cells and provide new ideas for targeted liver cancer therapy. Methods: The high-throughput CRISPR screening technology was used to screen the deubiquitinating enzymes that maintain the stemness of liver cancer stem cells. RT-qPCR and Western blot were used to analyze gene expression levels. Stemness of liver cancer cells was detected by spheroid-formation and soft agar colony formation assays. Tumor growth in nude mice was detected by subcutaneous tumor-bearing experiments. Bioinformatics and clinical samples were examined for the clinical significance of target genes. Results: MINDY1 was highly expressed in liver cancer stem cells. The expression of stem markers, the self-renewal ability of cells, and the growth of transplanted tumors were significantly reduced and inhibited after knocking out MINDY1, and its mechanism of action may be related to the regulation of the Wnt signaling pathway. The expression level of MINDY1 was higher in liver cancer tissues than that in adjacent tumors, which was closely related to tumor progression, and its high expression was an independent risk factor for a poor prognosis of liver cancer. Conclusion: The deubiquitinating enzyme MINDY1 promotes stemness in liver cancer cells and is one of the independent predictors of poor prognosis in liver cancer.

Constraints on Sub-GeV Dark Matter-Electron Scattering from the CDEX-10 Experiment.

We present improved germanium-based constraints on sub-GeV dark matter via dark matter-electron (χ-e) scattering using the 205.4 kg·day dataset from the CDEX-10 experiment. Using a novel calculation technique, we attain predicted χ-e scattering spectra observable in high-purity germanium detectors. In the heavy mediator scenario, our results achieve 3 orders of magnitude of improvement for m_{χ} larger than 80 MeV/c^{2} compared to previous germanium-based χ-e results. We also present the most stringent χ-e cross-section limit to date among experiments using solid-state detectors for m_{χ} larger than 90 MeV/c^{2} with heavy mediators and m_{χ} larger than 100 MeV/c^{2} with electric dipole coupling. The result proves the feasibility and demonstrates the vast potential of a new χ-e detection method with high-purity germanium detectors in ultralow radioactive background.

Exotic Dark Matter Search with the CDEX-10 Experiment at China's Jinping Underground Laboratory.

A search for exotic dark matter (DM) in the sub-GeV mass range has been conducted using 205 kg day data taken from a p-type point contact germanium detector of the CDEX-10 experiment at China's Jinping underground laboratory. New low-mass dark matter searching channels, neutral current fermionic DM absorption (χ+A→ν+A) and DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), have been analyzed with an energy threshold of 160 eVee. No significant signal was found; thus new limits on the DM-nucleon interaction cross section are set for both models at the sub-GeV DM mass region. A cross section limit for the fermionic DM absorption is set to be 2.5×10^{-46} cm^{2} (90% C.L.) at DM mass of 10 MeV/c^{2}. For the DM-nucleus 3→2 scattering scenario, limits are extended to DM mass of 5 and 14 MeV/c^{2} for the massless dark photon and bound DM final state, respectively.

Deep Underground Laboratory Measurement of

The ^{13}C(α,n)^{16}O reaction is the main neutron source for the slow-neutron-capture process in asymptotic giant branch stars and for the intermediate process. Direct measurements at astrophysical energies in above-ground laboratories are hindered by the extremely small cross sections and vast cosmic-ray-induced background. We performed the first consistent direct measurement in the range of E_{c.m.}=0.24 to 1.9 MeV using the accelerators at the China Jinping Underground Laboratory and Sichuan University. Our measurement covers almost the entire intermediate process Gamow window in which the large uncertainty of the previous experiments has been reduced from 60% down to 15%, eliminates the large systematic uncertainty in the extrapolation arising from the inconsistency of existing datasets, and provides a more reliable reaction rate for the studies of the slow-neutron-capture and intermediate processes along with the first direct determination of the alpha strength for the near-threshold state.

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_{ß} isotopes in commercial reactors.

[Expert consensus on measurement and clinical application of serum HBV RNA in patients with chronic HBV infection].

Since the discovery of circulating hepatitis B virus (HBV) RNA in the peripheral blood of patients with chronic hepatitis B in 1996, a growing number of studies have focused on clarifying the biological characteristics and clinical application value of serum HBV RNA. This consensus mainly summarizes the research progress of serum HBV RNA existing profiles, quantitative detection methods, and current clinical applications. In order to better apply this indicator for the clinical management of patients with chronic HBV infection, recommendations on quantitative detection target regions, detection results, and clinical applications are put forward.

[Analysis on the efficacy and safety of fibrinolytic therapy in patients with acute ST-segment elevation myocardial infarction during the COVID-19 epidemic].

Objective: To evaluate the efficacy and safety of fibrinolysis strategy in patients with acute ST-segment elevation myocardial infarction (STEMI) during the COVID-19 epidemic, and to provide reference value for optimization of fibrinolytic process on the premise of prevention and control of COVID-19 transmission, including self-protection of medical staff. Methods: The efficacy and safety of fibrinolysis were retrospectively analyzed in 7 patients with acute STEM, who hospitalized from February 29, 2020 to April 3, 2020 in the Department of Cardiology, Wuhan Union Hospital of Tongji Medical College, Huazhong University of Science and Technology. To optimize the fibrinolytic process on the premise of prevention and control of COVID-19 transmission, including self-protection of medical staff, a full-time medical team in charge of fibrinolysis under third-grade protection was established. The acute STEMI patients were treated immediately in a fixed and isolated area in emergency department before receiving green channel fibrinolysis. Blood samples for complete blood count, COVID-19 antibody test and nasopharyngeal swab samples for COVID-19 nucleic acid test were made before fibrinolysis, while the chest CT examination was accomplished after fibrinolysis. By comparing differences of time from the first electrocardiogram (ECG) to fibrinolysis before and after the improvement of fibrinolytic process, the effect of optimization of the fibrinolytic process was evaluated. Results: In the present study, seven patients with acute STEMI received fibrinolysis therapy, 6 of them achieved reperfusion and no bleeding was observed in all of the patients. Five out of the 7 patients were hospitalized after fibrinolysis, and the hospitalization days were 19.6 days on average. By following up to April 14, 2020, none of the 7 patients died. The first 2 patients were treated according to the routine medical procedure and the time from the first ECG to fibrinolysis were 201 and 106 minutes, respectively. After the optimization of the fibrinolytic process, the time from the first ECG to fibrinolysis of the last 5 patients were 42, 46, 51, 43 and 54 minutes, respectively，which was significantly shorter than that before optimization. Conclusions: During the COVID-19 epidemic, fibrinolysis in patients with acute STEMI is safe, effective and easy to implement. Therefore, it is recommended as the top priority for the patients with acute STEMI with indications for fibrinolysis. On the premise of prevention and control of COVID-19 transmission, including self-protection of medical staff, the duration of myocardial ischemia can be shortened by optimization of the fibrinolytic process.

TFAP2A is a novel regulator that modulates ferroptosis in gallbladder carcinoma cells via the Nrf2 signalling axis.

OBJECTIVE: Ferroptosis is a recently identified form of controlled cell death generally associated with the accumulation of lipid-associated reactive oxygen species (ROS). However, the molecular mechanisms underlying ferroptosis have not been established. MATERIALS AND METHODS: Microarray expression data for three human gallbladder carcinoma (GBC) and matched non-tumour specimens were downloaded from the Gene Expression Omnibus (GEO) repository. Candidate genes were filtered using bioinformatic analysis. After cell transfection, candidate gene impacts on cell proliferation, migration, invasion and ferroptosis (ferrous iron (Fe2+) and malondialdehyde (MDA) levels) were assessed. RESULTS: We screened 626 differentially expressed genes (DEGs) including 465 that were downregulated and 161 that were upregulated in the three tissue pairs. These DEGs were used to construct a protein-protein interaction (PPI) network. Functional enrichment analysis revealed the top three modules in the network and four hub genes. Transcription factor AP-2 alpha (TFAP2A) was screened and showed overexpression in The Cancer Genome Atlas (TCGA) digestive system tumour data and a relationship with clinical survival. In vitro, GBC exhibited upregulated expression of TFAP2A, whose inhibition reduced GBC cell proliferation, migration, and invasion. Fe2+ and MDA levels were elevated. Moreover, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed TFAP2A enrichment in oxidative stress. Subsequent experiments demonstrated that TFAP2A silencing attenuated the expression of key genes associated with oxidative stress such as heme oxygenase 1 (HO-1), nuclear factor erythroid 2 like 2 (Nrf2), ferritin heavy chain 1 (FTH1) and NAD(P)H quinone dehydrogenase 1 (NQO1). CONCLUSIONS: Bioinformatic and experimental analyses reveal that TFAP2A plays a vital role in ferroptosis and hence is a potential therapeutic target for GBC treatment.

Direct Detection Constraints on Dark Photons with the CDEX-10 Experiment at the China Jinping Underground Laboratory.

We report constraints on the dark photon effective kinetic mixing parameter (κ) with data taken from two p-type point-contact germanium detectors of the CDEX-10 experiment at the China Jinping Underground Laboratory. The 90% confidence level upper limits on κ of solar dark photon from 205.4 kg-day exposure are derived, probing new parameter space with masses (m_{V}) from 10 to 300 eV/c^{2} in direct detection experiments. Considering dark photon as the cosmological dark matter, limits at 90% confidence level with m_{V} from 0.1 to 4.0 keV/c^{2} are set from 449.6 kg-day data, with a minimum of κ=1.3×10^{-15} at m_{V}=200 eV/c^{2}.

Search for Light Weakly-Interacting-Massive-Particle Dark Matter by Annual Modulation Analysis with a Point-Contact Germanium Detector at the China Jinping Underground Laboratory.

We present results on light weakly interacting massive particle (WIMP) searches with annual modulation (AM) analysis on data from a 1-kg mass p-type point-contact germanium detector of the CDEX-1B experiment at the China Jinping Underground Laboratory. Datasets with a total live time of 3.2 yr within a 4.2-yr span are analyzed with analysis threshold of 250 eVee. Limits on WIMP-nucleus (χ-N) spin-independent cross sections as function of WIMP mass (m_{χ}) at 90% confidence level (C.L.) are derived using the dark matter halo model. Within the context of the standard halo model, the 90% C.L. allowed regions implied by the DAMA/LIBRA and CoGeNT AM-based analysis are excluded at >99.99% and 98% C.L., respectively. These results correspond to the best sensitivity at m_{χ}<6 GeV/c^{2} among WIMP AM measurements to date.

Constraints on Spin-Independent Nucleus Scattering with sub-GeV Weakly Interacting Massive Particle Dark Matter from the CDEX-1B Experiment at the China Jinping Underground Laboratory.

We report results on the searches of weakly interacting massive particles (WIMPs) with sub-GeV masses (m_{χ}) via WIMP-nucleus spin-independent scattering with Migdal effect incorporated. Analysis on time-integrated (TI) and annual modulation (AM) effects on CDEX-1B data are performed, with 737.1 kg day exposure and 160 eVee threshold for TI analysis, and 1107.5 kg day exposure and 250 eVee threshold for AM analysis. The sensitive windows in m_{χ} are expanded by an order of magnitude to lower DM masses with Migdal effect incorporated. New limits on σ_{χN}^{SI} at 90% confidence level are derived as 2×10^{-32}∼7×10^{-35} cm^{2} for TI analysis at m_{χ}∼50-180 MeV/c^{2}, and 3×10^{-32}∼9×10^{-38} cm^{2} for AM analysis at m_{χ}∼75 MeV/c^{2}-3.0 GeV/c^{2}.

[Clinical analysis of the risk factors for No.12p LN metastasis in advanced gastric cancer].

Objective: To analyse the risk factors for periportal lymphnode (No.12p LN) in advanced gastric cancer. Methods: A retrospective analysis of 183 patients with advanced gastric cancer from January 2005 to December 2010, and all patients were underwent D2 lymphadenectomy in addition to No. 12p LN dissections. Potential clinicopathological factors that could influence No. 12p LN metastasis were statistically analyzed. Results: There were 18 cases (9.8%) with periportal lymphnode metastasis. A logistic regression analysis suggested that the Borrmann type (Ⅲ/Ⅳ versus Ⅰ/Ⅱ, P=0.008), tumor size (≥6 cm vs <6 cm, P=0.001), and depth of invasion (pT4 vs pT2/pT3, P=0.049) were associated with 9.5-, 8.5-, and 3.2-fold increases, respectively, for risk of No. 12p LN metastasis. A logistic regression analysis also showed that No. 5 (P=0.002) and No. 12a (P=0.002) LN metastasis were associated with 7.5- and 7.3-fold increases, respectively, for risk of No. 12p LN metastasis. In addition, significant differences in 5-year survival of patients with and without No. 12p LN metastasis were observed (11.1% vs 32.7%, P=0.042). Conclusions: Borrmann type, tumor size and depth of invasion are significant factors for identifying patients with No. 12p LN metastasis. Patients with No. 5 or No. 12a LN metastasis should be higher possibility of No.12p LN metastasis.

Limits on Light Weakly Interacting Massive Particles from the First 102.8 kg×day Data of the CDEX-10 Experiment.

We report the first results of a light weakly interacting massive particles (WIMPs) search from the CDEX-10 experiment with a 10 kg germanium detector array immersed in liquid nitrogen at the China Jinping Underground Laboratory with a physics data size of 102.8 kg day. At an analysis threshold of 160 eVee, improved limits of 8×10^{-42} and 3×10^{-36} cm^{2} at a 90% confidence level on spin-independent and spin-dependent WIMP-nucleon cross sections, respectively, at a WIMP mass (m_{χ}) of 5 GeV/c^{2} are achieved. The lower reach of m_{χ} is extended to 2 GeV/c^{2}.

A rare oesophageal inflammatory myofibroblastic tumour treated by endoscopy.

An inflammatory myofibroblastic tumour is a mesenchymal neoplasm that mostly involves the lung and rarely involves the oesophagus. Surgery has been most commonly used for the treatment of oesophageal inflammatory myofibroblastic tumours but there are no definite guidelines for their diagnosis and treatment. We describe the case of a 60-year-old woman presenting with dysphagia and poor appetite who was diagnosed with a submucosal oesophageal tumour by contrast enhanced computed tomography and ultrasonography endoscopy. She was treated successfully by endoscopic submucosal dissection with no complications. The final diagnosis was confirmed by pathological examination.

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 ß 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.

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.

The identification of the biological characteristics of human ovarian cancer stem cells.

OBJECTIVE: Identifying the biological characteristics of previously screened ovarian cancer cell line HO8910-derived stem cells. MATERIALS AND METHODS: The pre-screening of ovarian cancer cell line HO8910-derived stem cells were subcultured (HO8910 cells were used as a control group) in serum-free medium. Firstly, the capacities of forming spheroids and self-renewal were observed. Then ovarian cancer stem cells (CSCs) were seeded in medium containing serum and cultured to observe the changes in their ability to differentiate. The stem cell-specific markers were also tested. Secondly, we tested the sensitivity of stem cells to cisplatin, doxorubicin, and mitoxantrone using drug susceptibility test. Finally, we inoculated the ovarian CSCs after passaging from culturing in serum-free media to NOD/SCID (non-obese diabetic/severe combined immunodeficient mice) mice in order to observe the tumorigenicity in vivo. RESULTS: Ovarian CSCs cultured in serum-free medium are capable of forming stable passaged cells spheres and have strong ability of self-renewal and differentiation. Under the condition of serum-free medium culture, the expression levels of CDl33+, CD117+, ABCG2, Nanog, Oct4, and BCRP in ovarian cancer stem cell are significantly higher than the counterparts in HO8910 cells. With the increase of the ability of differentiation, the stem cell marker expression levels reduced. While the differentiation, potential marker-E-cadherin expression levels were significantly lower than the control group. With the increase of the ability to differentiate, E-cadherin expression level was increased. Ovarian CSCs have significant resistance to cisplatin, doxorubicin, and mitoxantrone. NOD/SCID nude mice experiments showed that ovarian cancer stem cell tumorigenicity was significantly higher than control cells and has a continuous tumorigenicity. CONCLUSIONS: Comparing ovarian CSCs derived from HO8910 to HO8910 cells, the stem cells have significantly enhanced abilities of self-renewal, differentiation, in vivo tumorigenicity, highly expressed stem cell genes, and multidrug resistance.

Flaps for the repair of bladder exstrophy.

From April 1986 to March 1992, flaps were used in the surgical treatment of 17 patients with congenital bladder exstrophy. Eleven of these patients had had surgery in other hospitals but all failed. Using the flap method for the repair all of them had procured a functional bladder except one who could not have a complete control of urination. The longest follow-up period was 3 years, and the renal and bladder functions were completely normal. The immediate result in 14 patients was good in the control of urination right after the removal of the catheter. The follow-up results were good in 16 cases. The flaps used included 8 types of skin flaps, fasciae and vascular pedicles. Provided with the central vascular supply, the new series of procedures were suitable for the treatment of a variety of exstrophy deformities.

[Agyrophilic nucleolar organizer region counts as related to bromodeoxyuridine incorporation scores in ovarian clear cell carcinoma cells].

The value of agyrophilic nucleolar organizer region (AgNOR) stain as potential technique for the estimation of cell kinetics was assessed in this study. The daily AgNOR counts and the scores of the proliferation-associated marker bromodeoxyuridine (BrdU) in a human ovarian carcinoma cell line-OCC1 for 10 days after subculture were determined. The correlation between AgNOR counts and BrdU incorporation scores was highly significant (r = 0.86, P less than 0.01). Therefore AgNOR counts offer a potential tool to provide cytokinetic information.