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^{134}Xe is a candidate isotope for neutrinoless double beta decay (0νßß) search. In addition, the two-neutrino case (2νßß) allowed by the standard model of particle physics has not yet been observed. With the 656-kg natural xenon in the fiducial volume of the PandaX-4T detector, which contains 10.4% of ^{134}Xe, and its initial 94.9-day exposure, we have established the most stringent constraints on 2νßß and 0νßß of ^{134}Xe half-lives, with limits of 2.8×10^{22} yr and 3.0×10^{23} yr at 90% confidence level, respectively. The 2νßß (0νßß) limit surpasses the previously reported best result by a factor of 32 (2.7), highlighting the potential of large monolithic natural xenon detectors for double beta decay searches.
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OBJECTIVE: This study aims to assess how enhancing upper limb function on the affected side of stroke influences the gait of the lower limb. METHODS: Forty eligible stroke patients were randomly assigned to either a control group or a treatment group, with 20 patients in each group. Both groups underwent dynamic evaluation using artificial intelligence and computer vision before treatment. This evaluation focused on analyzing the range of motion of the shoulder and elbow during the gait cycle, as well as various gait parameters (such as step length, step speed, and percentage of stance phase) on the affected side. Following evaluation, the control group received routine rehabilitation treatment. RESULTS: The results indicated that there was no significant difference between the two groups before treatment. However, following treatment, there was a notable improvement in the motion of the shoulder and elbow joints on the affected side among patients in the treatment group (p<0.05), whereas the control group showed only slight improvement, which was not statistically significant (p>0.05). CONCLUSION: The improvement in upper limb function on the affected side also appears to positively influence gait recovery. However, it's important to note that the observation period was relatively short. Further studies are needed to confirm whether this effect is sustained over the long term.
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Inteligência Artificial , Terapia por Exercício , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Extremidade Superior , Humanos , Masculino , Feminino , Reabilitação do Acidente Vascular Cerebral/métodos , Pessoa de Meia-Idade , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/complicações , Extremidade Superior/fisiopatologia , Idoso , Terapia por Exercício/métodos , Marcha/fisiologia , Amplitude de Movimento Articular/fisiologia , Adulto , Recuperação de Função Fisiológica/fisiologia , Transtornos Neurológicos da Marcha/reabilitação , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologiaRESUMO
Gait adaptability is essential for stroke survivors to achieve efficient and safe community ambulation. However, conventional treadmill rehabilitation is only a repetitive practice of leg movement. This study compared the effects of augmented reality treadmill-based gait adaptation training with regular treadmill programs for patients with stroke. Forty patients with stroke (n = 40) were randomly assigned to the gait adaptation training {n = 20, age: 49.85 [standard deviation (SD) 8.44] years; onset of stroke: 107.80 (SD 48.31) days} and regular training [n = 20, age: 50.75 (SD 8.05) years, onset of stroke: 111.60 (SD 49.62) days] groups. Both groups completed three sessions of training per week for 5 weeks (15 sessions). The primary outcomes were the 10-m walk test and success rate of obstacle avoidance, while secondary outcomes included the Berg balance scale, component timed-up-and-go, and fall rate in a 6-month follow-up period. Assessments were performed before and after the intervention. The paired t-test was applied to compare the differences within groups and independent sample t-test was performed to compare the differences between groups. The 10-m walk test, success rate of obstacle avoidance, Berg balance scale, and component timed-up-and-go all significantly improved in the both groups (P < .001). The success rate of obstacle avoidance [P = .02, 95% confidence interval (CI): -21.07, -1.64], Berg Balance Scale (P = .02, 95% CI: -8.03, -0.67), 'turning around time' (P = .04, 95% CI: 0.08, 2.81), 'stand-to-sit' (P = .03, 95% CI: 0.16, 2.41) and 'total time' (P = .048, 95% CI: 0.04, 10.32) improved significantly in gait adaptation training group after intervention, while the 10-m walk test (P = .09, 95% CI: -0.17, 0.01), timed 'sit-to-stand' (P = .09, 95% CI: -0.14, 2.04), and 'linear walking' (P = .09, 95% CI: -0.27, 3.25) in gait adaptation training group did not show statistical difference compared to the regular training group. Total fall rate during the follow-up period was statistically decreased in the gait adaptation training group (P = .045). Both interventions improved mobility outcomes, with augmented reality treadmill-based gait adaptation indicating greater improvement in obstacle avoidance, balance, turning, and stand-to-sit. Augmented reality treadmill-based gait adaptation training emerges as an effective and promising intervention for patients with stroke in early rehabilitation.
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Realidade Aumentada , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Pessoa de Meia-Idade , Caminhada , Acidente Vascular Cerebral/complicações , Marcha , Resultado do TratamentoRESUMO
We report a search for light dark matter produced through the cascading decay of η mesons, which are created as a result of inelastic collisions between cosmic rays and Earth's atmosphere. We introduce a new and general framework, publicly accessible, designed to address boosted dark matter specifically, with which a full and dedicated simulation including both elastic and quasielastic processes of Earth attenuation effect on the dark matter particles arriving at the detector is performed. In the PandaX-4T commissioning data of 0.63 tonne·year exposure, no significant excess over background is observed. The first constraints on the interaction between light dark matter generated in the atmosphere and nucleus through a light scalar mediator are obtained. The lowest excluded cross section is set at 5.9×10^{-37} cm^{2} for a dark matter mass of 0.1 MeV/c^{2} and mediator mass of 300 MeV/c^{2}. The lowest upper limit of η to the dark matter decay branching ratio is 1.6×10^{-7}.
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We report the search results of light dark matter through its interactions with shell electrons and nuclei, using the commissioning data from the PandaX-4T liquid xenon detector. Low energy events are selected to have an ionization-only signal between 60 to 200 photoelectrons, corresponding to a mean nuclear recoil energy from 0.77 to 2.54 keV and electronic recoil energy from 0.07 to 0.23 keV. With an effective exposure of 0.55 tonne·year, we set the most stringent limits within a mass range from 40 MeV/c^{2} to 10 GeV/c^{2} for pointlike dark matter-electron interaction, 100 MeV/c^{2} to 10 GeV/c^{2} for dark matter-electron interaction via a light mediator, and 3.2 to 4 GeV/c^{2} for dark matter-nucleon spin-independent interaction. For DM interaction with electrons, our limits are closing in on the parameter space predicted by the freeze-in and freeze-out mechanisms in the early Universe.
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Núcleo Celular , ElétronsRESUMO
We report results of a search for dark-matter-nucleon interactions via a dark mediator using optimized low-energy data from the PandaX-4T liquid xenon experiment. With the ionization-signal-only data and utilizing the Migdal effect, we set the most stringent limits on the cross section for dark matter masses ranging from 30 MeV/c^{2} to 2 GeV/c^{2}. Under the assumption that the dark mediator is a dark photon that decays into scalar dark matter pairs in the early Universe, we rule out significant parameter space of such thermal relic dark-matter model.
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A search for interactions from solar ^{8}B neutrinos elastically scattering off xenon nuclei using PandaX-4T commissioning data is reported. The energy threshold of this search is further lowered compared with the previous search for dark matter, with various techniques utilized to suppress the background that emerges from data with the lowered threshold. A blind analysis is performed on the data with an effective exposure of 0.48 tonne year, and no significant excess of events is observed. Among the results obtained using the neutrino-nucleus coherent scattering, our results give the best constraint on the solar ^{8}B neutrino flux. We further provide a more stringent limit on the cross section between dark matter and nucleon in the mass range from 3 to 9 GeV/c^{2}.
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This report introduces a young adult who has been in bed for more than ten years with end-stage hemophilic arthropathy. He didn't have access to factor VIII (FVIII) in the early stage of hemophilia due to the high costs of clotting replacement therapy. As a result, he is experiencing some difficulties, such as joint contracture, muscular atrophy, severe pain, and poor function of cardiopulmonary. He came to visit us for a comprehensive rehabilitation program, and, finally, he achieved the basic goal of self-care in daily life.
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Artrite , Hemofilia A , Artropatias , Masculino , Adulto Jovem , Humanos , Hemofilia A/complicações , Hemofilia A/terapia , Modalidades de Fisioterapia , Artropatias/complicações , Artropatias/diagnóstico por imagemRESUMO
We report a novel search for the cosmic-ray boosted dark matter using the 100 tonne·day full dataset of the PandaX-II detector located at the China Jinping Underground Laboratory. With the extra energy gained from the cosmic rays, sub-GeV dark matter particles can produce visible recoil signals in the detector. The diurnal modulations in rate and energy spectrum are utilized to further enhance the signal sensitivity. Our result excludes the dark matter-nucleon elastic scattering cross section between 10^{-31} and 10^{-28} cm^{2} for dark matter masses from 0.1 MeV/c^{2} to 0.1 GeV/c^{2}, with a large parameter space previously unexplored by experimental collaborations.
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Compared with the signature of dark matter elastic scattering off nuclei, the absorption of fermionic dark matter by nuclei opens up a new searching channel for light dark matter with a characteristic monoenergetic signal. In this Letter, we explore the 95.0-day data from the PandaX-4T commissioning run and report the first dedicated searching results of the fermionic dark matter absorption signal through a neutral current process. No significant signal was found, and the lowest limit on the dark matter-nucleon interaction cross section is set to be 1.5×10^{-50} cm^{2} for a fermionic dark matter mass of 40 MeV/c^{2} with 90% confidence level.
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We report a search on sub-MeV fermionic dark matter absorbed by electrons with an outgoing active neutrino using the 0.63 tonne year exposure collected by the PandaX-4T liquid xenon experiment. No significant signals are observed over the expected background. The data are interpreted into limits to the effective couplings between such dark matter and the electron. For axial-vector or vector interactions, our sensitivity is competitive in comparison to existing astrophysical bounds on the decay of such a dark matter candidate into photon final states. In particular, we present the first direct detection limits for a vector (axial-vector) interaction which are the strongest in the mass range from 35 to 55 (25 to 45) keV/c^{2} in comparison to other astrophysical and cosmological constraints.
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We report the first dark matter search results using the commissioning data from PandaX-4T. Using a time projection chamber with 3.7 tonne of liquid xenon target and an exposure of 0.63 tonne·year, 1058 candidate events are identified within an approximate nuclear recoil energy window between 5 and 100 keV. No significant excess over background is observed. Our data set a stringent limit to the dark matter-nucleon spin-independent interactions, with a lowest excluded cross section (90% C.L.) of 3.8×10^{-47} cm^{2} at a dark matter mass of 40 GeV/c^{2}.
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We report constraints on light dark matter through its interactions with shell electrons in the PandaX-II liquid xenon detector with a total 46.9 tonnes/day exposure. To effectively search for these very low energy electron recoils, ionization-only signals are selected from the data. 1821 candidates are identified within an ionization signal range between 50 and 75 photoelectrons, corresponding to a mean electronic recoil energy from 0.08 to 0.15 keV. The 90% C.L. exclusion limit on the scattering cross section between the dark matter and electron is calculated with systematic uncertainties properly taken into account. Under the assumption of point interaction, we provide the world's most stringent limit within the dark matter mass range from 15 to 30 MeV/c^{2}, with the corresponding cross section from 2.5×10^{-37} to 3.1×10^{-38} cm^{2}.
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Compounds derived from natural products present satisfactory efficacy in disease prevention and treatment. The use of chemical substances in plants to promote healthhas increasingly attracted people's attention. Rutin, a typical flavonoid, is mainly found in various vegetables, fruits and Chinese herbal medicines. As a natural antioxidant, it features many pharmacological activities, such as anti-inflammation, anti-virus, anti-tumor, and prevention and treatment of cardiovascular and cerebrovascular diseases. However, the low bioavailability and poor water solubility limit its clinical application. In view of this, its structure is optimized and modified to afford rutin derivatives with good solubility, high bioavailability, stable metabolism and small toxic side effects. So far, a large number of rutin ethers, esters, and complexes have been synthesized and undergone activity testing. This paper reviews the structural modification of rutin in recent years, and the obtained derivatives have excellent properties and significant biological activity.
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Anti-Inflamatórios , Rutina , Antioxidantes , Disponibilidade Biológica , Humanos , SolubilidadeRESUMO
We search for nuclear recoil signals of dark matter models with a light mediator in PandaX-II, a direct detection experiment in the China Jinping underground laboratory. Using data collected in 2016 and 2017 runs, corresponding to a total exposure of 54 ton day, we set upper limits on the zero-momentum dark matter-nucleon cross section. These limits have a strong dependence on the mediator mass when it is comparable to or below the typical momentum transfer. We apply our results to constrain self-interacting dark matter models with a light mediator mixing with standard model particles, and set strong limits on the model parameter space for the dark matter mass ranging from 5 GeV to 10 TeV.
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We report new searches for solar axions and galactic axionlike dark matter particles, using the first low-background data from the PandaX-II experiment at China Jinping Underground Laboratory, corresponding to a total exposure of about 2.7×10^{4} kg day. No solar axion or galactic axionlike dark matter particle candidate has been identified. The upper limit on the axion-electron coupling (g_{Ae}) from the solar flux is found to be about 4.35×10^{-12} in the mass range from 10^{-5} to 1 keV/c^{2} with 90% confidence level, similar to the recent LUX result. We also report a new best limit from the ^{57}Fe deexcitation. On the other hand, the upper limit from the galactic axions is on the order of 10^{-13} in the mass range from 1 to 10 keV/c^{2} with 90% confidence level, slightly improved compared with the LUX.
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New constraints are presented on the spin-dependent weakly-interacting-massive-particle- (WIMP-)nucleon interaction from the PandaX-II experiment, using a data set corresponding to a total exposure of 3.3×10^{4} kg day. Assuming a standard axial-vector spin-dependent WIMP interaction with ^{129}Xe and ^{131}Xe nuclei, the most stringent upper limits on WIMP-neutron cross sections for WIMPs with masses above 10 GeV/c^{2} are set in all dark matter direct detection experiments. The minimum upper limit of 4.1×10^{-41} cm^{2} at 90% confidence level is obtained for a WIMP mass of 40 GeV/c^{2}. This represents more than a factor of 2 improvement on the best available limits at this and higher masses. These improved cross-section limits provide more stringent constraints on the effective WIMP-proton and WIMP-neutron couplings.
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We report a new search for weakly interacting massive particles (WIMPs) using the combined low background data sets acquired in 2016 and 2017 from the PandaX-II experiment in China. The latest data set contains a new exposure of 77.1 live days, with the background reduced to a level of 0.8×10^{-3} evt/kg/day, improved by a factor of 2.5 in comparison to the previous run in 2016. No excess events are found above the expected background. With a total exposure of 5.4×10^{4} kg day, the most stringent upper limit on the spin-independent WIMP-nucleon cross section is set for a WIMP with mass larger than 100 GeV/c^{2}, with the lowest 90% C.L. exclusion at 8.6×10^{-47} cm^{2} at 40 GeV/c^{2}.
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We report the weakly interacting massive particle (WIMP) dark matter search results using the first physics-run data of the PandaX-II 500 kg liquid xenon dual-phase time-projection chamber, operating at the China JinPing underground laboratory. No dark matter candidate is identified above background. In combination with the data set during the commissioning run, with a total exposure of 3.3×10^{4} kg day, the most stringent limit to the spin-independent interaction between the ordinary and WIMP dark matter is set for a range of dark matter mass between 5 and 1000 GeV/c^{2}. The best upper limit on the scattering cross section is found 2.5×10^{-46} cm^{2} for the WIMP mass 40 GeV/c^{2} at 90% confidence level.
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Background: Currently, the use of spinal cord electrical stimulations for patients with severe disorders of consciousness after traumatic brain injury remains limited, and long-term follow-up studies are even scarcer. To date, there have been few reports using near-infrared spectroscopy to evaluate the clinical effects and optimal parameters of spinal cord electrical stimulation for severe consciousness disorders. This report describes a case of a patient with severe disturbance of consciousness after traumatic brain injury who underwent spinal cord electrical stimulation implantation. Advanced near-infrared spectroscopy was employed to monitor and evaluate postoperative efficacy. The findings of this case report will provide a reference for the clinical treatment of severe consciousness disturbances. Methods: A patient diagnosed with a severe disturbance of consciousness following traumatic brain injury presented symptoms of coma and lack of voluntary activity. The treatment regimen included conventional approaches (medication combined with rehabilitation training) and adjustments to the spinal cord electrical stimulation parameters. Advanced functional near-infrared spectroscopy (fNIRS) was used to explore changes in brain functional connectivity strength and assess clinical efficacy. Results: The integration of conventional treatment and continuous modification of spinal cord electrical stimulation parameters, combined with fNIRS monitoring, demonstrated that conventional treatment and spinal cord electrical stimulation displayed a positive effect on increasing brain functional strength connection. The Glasgow Coma Scale(GCS) score significantly improved from the baseline. Optimal results were observed with spinal cord stimulation settings at 4.5 V amplitude, 210 µs pulse width, and 70 Hz frequency, operating from 8:00-20:00 in a cycling mode of 15 min on and 15 min off, where improvements in consciousness were markedly evident. Conclusions: Patients with severe disturbances of consciousness after traumatic brain injury recover slowly. Conventional treatment combined with spinal cord electrical stimulation can improve the degree of disturbance of consciousness and promote recovery from the condition.