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1.
Phys Rev Lett ; 132(17): 171001, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38728703

RESUMEN

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.

2.
Phys Rev Lett ; 129(22): 221301, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36493436

RESUMEN

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.


Asunto(s)
Electricidad , Electrones
3.
Phys Rev Lett ; 129(22): 221802, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36493447

RESUMEN

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.


Asunto(s)
Núcleo Celular , Fotones
4.
Phys Rev Lett ; 124(11): 111301, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-32242731

RESUMEN

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}.

5.
Zhonghua Gan Zang Bing Za Zhi ; 28(10): 816-819, 2020 Oct 20.
Artículo en Zh | MEDLINE | ID: mdl-33105923

RESUMEN

The micro-elimination strategy is an effective approach to rapidly reduce the incidence and mortality of specific populations infected with hepatitis C virus (HCV). This article combines the current status of hepatitis C prevention and treatment in Guizhou Province, and introduces the current domestic and foreign hepatitis C micro-elimination models. It is worth mentioning that the Guizhou Provincial Medical Quality Control Center for Infectious Diseases jointly formulated the "Guizhou Province Chronic Hepatitis C Health Education Standards" to improve the awareness of health care workers and patients about the disease, increase the screening rate, and increase the patients willingness to receive treatment and accomplish the World Health Organization's goal of eliminating hepatitis C threat by 2030.


Asunto(s)
Educación en Salud , Hepatitis C Crónica , China , Hepacivirus , Hepatitis C Crónica/epidemiología , Hepatitis C Crónica/prevención & control , Humanos , Organización Mundial de la Salud
6.
Phys Rev Lett ; 123(16): 161301, 2019 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-31702340

RESUMEN

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}.

7.
Artículo en Zh | MEDLINE | ID: mdl-31189244

RESUMEN

Objective: Evaluation of improving the occupational protective effect of nurses in cytotoxic drugs. Methods: The occupational hazards of cytotoxic drugs in Qingdao Central hospital were taken as samples. Compare the occupational hazards of cytotoxic drugs before and after improvement. Results: From Sept.2017 to Aug.2018, the number of occupational hazards of cytotoxic drugs decreased by 90.38%; Sharp injuries, drug spillovers, distribution errors and excessive air diffusivity were decreased by 70%~100%. Conclusion: Targeted occupational protection can significantly reduce the hazards of cytotoxic drugs and ensure the health of the medicinal staff.


Asunto(s)
Citotoxinas , Enfermeras y Enfermeros , Exposición Profesional , Humanos , Exposición Profesional/prevención & control , Seguridad
8.
Zhonghua Yan Ke Za Zhi ; 53(12): 941-946, 2017 Dec 11.
Artículo en Zh | MEDLINE | ID: mdl-29325387

RESUMEN

Objective: To report the clinical results of pediatric penetrating keratoplasty (PKP) in patients under 3 years old with congenital corneal opacity. Methods: Retrospective study. Sixteen eyes of 12 patients who were treated with PKP in Aier Eye Hospital Group from June 2009 to December 2016 were enrolled in this study. All the patients were diagnosed as congenital corneal opacities: 8 cases (11 eyes) with Peter's anomaly I, 2 cases (3 eyes) with sclerocornea, and 2 cases (2 eyes) with corneal dermoid tumor combined with iris synechia. Seven cases (7 eyes) were under 1 year old. Eight cases (10 eyes) could not follow the light. Only 1 case (2 eyes) received PKP with extracapsular cataract extraction, and the others only had PKP. Postoperative examinations were performed more frequently than in adults, and sometimes general anesthesia was needed. Results: The follow-up period was from 8 months to 6 years (33.17±22.60 months). The postoperative visual acuity improvement was found in all eyes from 1 week to 1 month after surgery except a 3-year-old patient with corneal dermoid tumor with serious esotropia. All the surgeries were successful without intraoperative complications. Graft rejection occurred in 4 cases (4 eyes). The graft of a 33-month-old patient became semitransparent. The grafts of 2 cases under 1 year old were clear after drug therapy. And the vision of a 3-year-old patient with Peter anomaly improved obviously, but immune rejection occurred 2 years after surgery. The second PKP was performed, but rejection occurred again. Secondary glaucoma was found in the other eye early after operation; anti-glaucoma surgery failed, and the graft became cloudy. Graft infection associated with loosened sutures was observed in one case (2 eyes) of sclerocornea, and the second PKP failed. Conclusions: For the patients with congenital corneal opacities, there is often a noticeable visual improvement after PKP. Good postoperative care, appropriate amblyopia treatment and timely examination are the keys to success. (Chin J Ophthalmol, 2017, 53: 941-946).


Asunto(s)
Enfermedades de la Córnea , Opacidad de la Córnea , Queratoplastia Penetrante , Preescolar , Enfermedades de la Córnea/cirugía , Opacidad de la Córnea/cirugía , Estudios de Seguimiento , Humanos , Lactante , Complicaciones Posoperatorias , Estudios Retrospectivos , Resultado del Tratamiento
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