The CDEX-1 1 kg Point-Contact Germanium Detector for Low Mass Dark Matter Searches

The CDEX Collaboration has been established for direct detection of light dark matter particles, using ultra-low energy threshold p-type point-contact germanium detectors, in China JinPing underground Laboratory (CJPL). The first 1 kg point-contact germanium detector with a sub-keV energy threshold has been tested in a passive shielding system located in CJPL. The outputs from both the point-contact p+ electrode and the outside n+ electrode make it possible to scan the lower energy range of less than 1 keV and at the same time to detect the higher energy range up to 3 MeV. The outputs from both p+ and n+ electrode may also provide a more powerful method for signal discrimination for dark matter experiment. Some key parameters, including energy resolution, dead time, decay times of internal X-rays, and system stability, have been tested and measured. The results show that the 1 kg point-contact germanium detector, together with its shielding system and electronics, can run smoothly with good performances. This detector system will be deployed for dark matter search experiments.Comment: 6 pages, 8 figure

A simulation study on the measurement of D0-D0bar mixing parameter y at BES-III

We established a method on measuring the \dzdzb mixing parameter $y$ for BESIII experiment at the BEPCII $e^+e^-$ collider. In this method, the doubly tagged $\psi(3770) \to D^0 \overline{D^0}$ events, with one $D$ decays to CP-eigenstates and the other $D$ decays semileptonically, are used to reconstruct the signals. Since this analysis requires good $e/\pi$ separation, a likelihood approach, which combines the $dE/dx$, time of flight and the electromagnetic shower detectors information, is used for particle identification. We estimate the sensitivity of the measurement of $y$ to be 0.007 based on a $20fb^{-1}$ fully simulated MC sample.Comment: 6 pages, 7 figure

End-to-End Quantum Vision Transformer: Towards Practical Quantum Speedup in Large-Scale Models

The field of quantum deep learning presents significant opportunities for advancing computational capabilities, yet it faces a major obstacle in the form of the "information loss problem" due to the inherent limitations of the necessary quantum tomography in scaling quantum deep neural networks. This paper introduces an end-to-end Quantum Vision Transformer (QViT), which incorporates an innovative quantum residual connection technique, to overcome these challenges and therefore optimize quantum computing processes in deep learning. Our thorough complexity analysis of the QViT reveals a theoretically exponential and empirically polynomial speedup, showcasing the model's efficiency and potential in quantum computing applications. We conducted extensive numerical tests on modern, large-scale transformers and datasets, establishing the QViT as a pioneering advancement in applying quantum deep neural networks in practical scenarios. Our work provides a comprehensive quantum deep learning paradigm, which not only demonstrates the versatility of current quantum linear algebra algorithms but also promises to enhance future research and development in quantum deep learning.Comment: 24pages, 10 figure

Jugular venous reflux and brain parenchyma volumes in elderly patients with mild cognitive impairment and Alzheimer's disease.

BACKGROUND: To determine whether or not jugular venous reflux (JVR) is associated with structural brain parenchyma changes in individuals with mild cognitive impairment (MCI) and Alzheimer's disease (AD). METHODS: 16 AD patients (mean (SD): 81.9 (5.8) years), 33 MCI patients (mean (SD): 81.4 (6.1) years) and 18 healthy elderly controls (mean (SD): 81.5 (3.4) years) underwent duplex ultrasonography and magnetic resonance imaging scans to quantify structural brain parenchyma changes. Normalized whole brain (WB), gray matter (GM) and white matter (WM) volumes were collected, together with CSF volume. RESULTS: JVR was strongly associated with increased normalized WB (p = 0.014) and GM (p = 0.002) volumes across all three subject groups. There was a trend towards increased WB and GM volumes, which was accompanied by decreased CSF volume, in the JVR-positive subjects in both the MCI and AD groups. When the MCI and AD subjects were aggregated together significant increases were observed in both normalized WB (p = 0.009) and GM (p = 0.003) volumes for the JVR-positive group. No corresponding increases were observed for the JVR-positive subjects in the control group. Through receiver operating characteristic analysis of the brain volumetric data it was possible to discriminate between the JVR-positive and negative AD subjects with reasonable accuracy (sensitivity = 71.4%; specificity = 88.9%; p = 0.007). CONCLUSIONS: JVR is associated with intracranial structural changes in MCI and AD patients, which result in increased WB and GM volumes. The neuropathology of this unexpected and counterintuitive finding requires further investigation, but may suggest that JVR retrogradely transmits venous hypertension into the brain and leads to brain tissues swelling due to vasogenic edema

Simulation of open quantum systems on universal quantum computers

The rapid development of quantum computers has enabled demonstrations of quantum advantages on various tasks. However, real quantum systems are always dissipative due to their inevitable interaction with the environment, and the resulting non-unitary dynamics make quantum simulation challenging with only unitary quantum gates. In this work, we present an innovative and scalable method to simulate open quantum systems using quantum computers. We define an adjoint density matrix as a counterpart of the true density matrix, which reduces to a mixed-unitary quantum channel and thus can be effectively sampled using quantum computers. This method has several benefits, including no need for auxiliary qubits and noteworthy scalability. Moreover, accurate long-time simulation can also be achieved as the adjoint density matrix and the true dissipated one converge to the same state. Finally, we present deployments of this theory in the dissipative quantum $XY$ model for the evolution of correlation and entropy with short-time dynamics and the disordered Heisenberg model for many-body localization with long-time dynamics. This work promotes the study of real-world many-body dynamics with quantum computers, highlighting the potential to demonstrate practical quantum advantages.Comment: 13 pages, 6 figure

Radix sophorae flavescentis versus other drugs or herbs for chronic hepatitis B

Background Hepatitis B virus (HBV) infection is a liver disease caused by hepatitis B virus, which may lead to serious complications such as cirrhosis and hepatocellular carcinoma. People with HBV infection may also have coinfections including HIV and other hepatitis viruses (hepatitis C or D), and coinfections may increase the risk of all-cause mortality. Chronic HBV infection increases morbidity, psychological stress, and it is an economic burden on people with chronic hepatitis B and their families. Radix Sophorae flavescentis, a herbal medicine, is administered mostly in combination with other drugs or herbs. It is believed that it decreases discomfort and prevents the replication of the virus in people with chronic hepatitis B. However, the benefits and harms of Radix Sophorae flavescentis on patient-centred outcomes are unknown, and its wide usage has never been established with rigorous review methodology. Objectives To assess the benefits and harms of Radix Sophorae flavescentis versus other drugs or herbs in people with chronic hepatitis B. Search methods We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE, Embase, and seven other databases to December 2018. We also searched the World Health Organization International Clinical Trials Registry Platform ( www.who.int/ictrp), ClinicalTrials.gov ( www.clinicaltrials.gov/), and the Chinese Clinical Trial Registry for ongoing or unpublished trials to December 2018. Selection criteria We included randomised clinical trials, irrespective of publication status, language, or blinding, comparing Radix Sophorae flavescentis versus other drugs or herbs for people with chronic hepatitis B. In addition to chronic hepatitis B, participants could also have had cirrhosis, hepatocellular carcinoma, or any other concomitant disease. We excluded polyherbal blends containing Radix Sophorae flavescentis. We allowed cointerventions when the cointerventions were administered equally to all intervention groups. Data collection and analysis Review authors in pairs individually retrieved data from published reports and after correspondence with investigators. Our primary outcomes were all-cause mortality, serious adverse events, and health-related quality of life. Our secondary outcomes were hepatitis B-related mortality, hepatitis B-related morbidity, and adverse events considered ’not to be serious’. We presented the meta-analysed results as risk ratios (RR) with 95% confidence intervals (CI). We assessed the risk of bias using domains with predefined definitions. We conducted Trial Sequential Analyses to control the risks of random errors. We used GRADE methodology to evaluate our certainty in the evidence (i.e. “the extent of our confidence that the estimates of the effect are correct or are adequate to support a particular decision or recommendation”). Main results We included 10 randomised clinical trials with 898 participants. We judged all trials at high risk of bias. The trials covered oral capsules, intravenous infusion, intramuscular injection, and acupoint (a specifically chosen site of acupuncture) injection of Radix Sophorae flavescentis with a follow-up period from 1 to 12 months. The drugs being used as a comparator were lamivudine, adefovir, interferon, tiopronin, thymosin, or other Chinese herbs. Two trials included children up to 14 years old. Participants in one trial had cirrhosis in chronic hepatitis B. None of the trials reported all-cause mortality, health-related quality of life, serious adverse events, hepatitis B-related mortality, or morbidity. We are uncertain as to whether Radix Sophorae flavescentis has a beneficial or harmful effect on adverse events considered ’not to be serious’ (RR 0.86, 95% CI 0.42 to 1.75; I2 = 0%; 2 trials, 163 participants; very low-certainty evidence), as well as if it decreases or increases the proportion of participants with detectable HBV-DNA (RR 1.14, 95% CI 0.81 to 1.63; I2 = 92%; 8 trials, 719 participants; very low-certainty evidence). Radix Sophorae flavescentis showed a reduction in the proportion of participants with detectable hepatitis B virus e-antigen (HBeAg) (RR 0.86, 95% CI 0.75 to 0.98; I2 = 43%; 7 trials, 588 participants; very low-certainty evidence). Two of the 10 trials were not funded, and one received academic funding. The remaining seven trials provided no information on funding. The randomisation process in another 109 trials was insufficiently reported to ensure the inclusion of any of these studies in our review. Authors’ conclusions The included trials lacked data on all-cause mortality, health-related quality of life, serious adverse events, hepatitis-B related mortality, and hepatitis-B related morbidity. The evidence on the effect of Radix Sophorae flavescentis on the proportion of participants with adverse events considered ’not to be serious’ and on the proportion of participants with detectable HBV-DNA is still unclear. We advise caution regarding the results of Radix Sophorae flavescentis showing a reduction in the proportion of people with detectable HBeAg because the trials were at high risk of bias, because it is a non-validated surrogate outcome, and because of the very low certainty in the evidence. As we were unable to obtain information on a large number of studies regarding their trial design, we were deterred from including them in our review. Undisclosed funding may have influence on trial results and lead to poor design of the trial. In view of the wide usage of Radix Sophorae flavescentis, we need large, unbiased, high-quality placebo-controlled randomised trials assessing patient-centred outcomes.</p

The Association Between Post-stroke Depression, Aphasia, and Physical Independence in Stroke Patients at 3-Month Follow-Up

Objective: Few studies have examined the association between post-stroke depression (PSD), aphasia, and physical independence in Chinese patients. This study investigated the above association in stroke patients in China at 3-month follow-up.Methods: Altogether 270 patients within 14 days after ischemic stroke were recruited and followed up at 3 months. PSD, aphasia, and physical functional status were measured using the Stroke Aphasia Depression Questionnaire (SADQ), Western Aphasia Battery (WAB), and modified Rankin Scale (mRS), respectively. Patients with mRS total score &gt;2 were considered as having “physical dependence.”Results: Out of 248 patients at 3-month follow up, 119 (48%) were rated as having physical dependence. Multiple logistic regression analyses revealed that female (p = 0.04; OR = 2.2; 95% CI: 1.0–5.1), more severe stroke at admission (p &lt; 0.01; OR = 1.4; 95% CI: 1.3–1.5), and more severe PSD at 3 months (p = 0.01; OR = 1.05; 95% CI: 1.01–1.1) were independently associated with physical dependence at 3 months.Conclusions: Greater PSD and stroke severity were independently associated with physical dependence at 3 months after stroke. Aphasia was also associated with physical dependence but the relationship was not significant. Early and effective depression screening, treatment and stroke rehabilitation appear to be important to improve the physical outcome and reduce the burden of stroke survivors