12 research outputs found
Quantum Computation and Quantum Simulation with Atomic and Solid State Systems.
Get PDFThe ability to manipulate individual quantum systems in a precise way has led to a new era of quantum technologies, including quantum computation and quantum simulation. In this thesis we present several new implementations of these quantum technologies.
We first aim at addressing current experimental challenges for quantum dot based quantum computing. We propose a systematic way to study the dynamics of nuclear spin, which is responsible for the short electron spin coherence time. Our calculation is based on diffusion model and is consistent with experiments. We also invent a novel protocol to realize high-fidelity ultrafast universal quantum gate in recently-developed quantum dot molecule system. Experimental realization of our protocol requires only a simple time engineering of optical pulses.
We then propose a new quantum state transfer scheme for Nitrogen-Vacancy center based quantum computer, which is applicable at room temperature. Our method accomplishes high fidelity robust quantum state transfer through uncontrolled thermal nitrogen spin chain between two remote NV registers.
Our next study helps building a hybrid quantum computer by entangling disparate systems using photonic links. The photons emitted from two types of system need to be matched in both frequency and pulse shape. We propose a simple method to match the emitted pulse shape from two qubit systems with different transition linewidths.
We then focus on quantum simulation with trapped ions. We show the possibility of observing a novel type of temperature driven structural phase transition in trapped ion chain, which originates from anharmonic interaction between different vibrational modes. Afterward, an experimental protocol to simulate a conceptually new state of matter, called time crystal, is proposed based on ions trapped in a ring trap.
Finally, we propose two new applications based on the recently developed trapped ion quantum simulator of spin models: (1) simulation of Haldane-Shastry model, which opens the way of experimental study to a remarkable theoretical model involving spin liquid ground state and fractional excitations (2) observation of prethermalization and dynamical phase transition, which are poorly understood non-equilibrium phenomena in closed quantum many-body system.PhDPhysicsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/99847/1/gzx_1.pd
Association between neutrophil-platelet ratio and 28-day mortality in patients with sepsis: a retrospective analysis based on MIMIC-IV database
No full textAbstract Background The immune system and inflammation are intimately linked to the pathophysiology of sepsis. The neutrophil‒platelet ratio (NPR), associated with inflammation and immunology, may be useful in predicting sepsis outcomes. According to earlier research, the NPR is linked to the prognosis of several diseases. This study aimed to investigate the connection between the NPR and unfavorable outcomes in patients with sepsis. Methods We retrieved patient clinical data from the Medical Information Mart for Intensive Care IV database (MIMIC-IV 2.2) based on the inclusion and exclusion criteria. The NPR quartile was used to divide the population into four groups. 28-day mortality was the main result, whereas 90-day mortality was the secondary result. The Cox regression model, Kaplan‒Meier survival curve, and limited cubic spline were used to examine the associations between the NPR and the negative outcomes of sepsis. Subgroup analysis was also conducted. At the same time, we used Latent Class Trajectory Model (LCTM) to assess the trajectory of NPR within six days of ICU admission, and to assess the relationship between NPR trajectory and mortality at 28 and 90 days. Results This study included 3339 patients. Quartile 4 had the greatest 28-day and 90-day mortality rates, according to the Cox regression model and Kaplan‒Meier survival curve. A J-shaped relationship between the NPR and mortality was found in restricted cubic spline investigations. This means higher and lower NPRs were linked to higher mortality, with NPR = 3.81 as the tipping point. A total of 434 patients were included in the trajectory analysis, and three trajectory patterns were identified. Patients with sepsis had an increased mortality rate in the slow-decline group compared with the stable development group. Conclusion The NPR has prognostic value for patients with sepsis, and there is a J-shaped relationship between the two variables. Patients with sepsis who have a slowly declining NPR have an increased mortality rate. Clinical trial Not applicable
Patterns of species richness in relation to temperature, taxonomy and spatial scale in eastern China
No full textFacile Fabrication of Cellulose Nanofibrils/Chitosan Beads as the Potential pH-Sensitive Drug Carriers
No full textIt is highly desirable to develop a safe, highly efficient, and biodegradable drug carrier with an enhanced drug transport efficiency. Cellulose nanofibrils (CNF) and chitosan (CS) composite hydrogels are promising candidate carriers with biological compatibility and non-cytotoxicity. Herein, the CNF/CS composite beads were prepared by dissolving cellulose and CS in LiBr molten salt hydrate and regenerating in ethanol. This preparation method is facile and efficient, and the obtained porous CNF/CS beads with the weight ratio of 8:2 exhibited a large specific surface area, uniform micro-nano-sized pores, strong mechanical property, and water absorption-resistance. Moreover, these beads as drug (tetracycline hydrochloride, TH) carriers showed a higher encapsulation efficiency (47.4%) at the TH concentration of 5 mg/mL in 24 h, and a higher drug loading rate (12.0%) than pure CNF and other CNF/CS beads prepared with different ratios. In addition, the TH releasing behavior of CNF/CS (8:2) beads fitted well into the zero-order, first-order, and Higuchi models under an acid condition, indicating that the drug release of these pH-sensitive beads was mainly affected by drug concentration under an acid condition. Therefore, these CNF/CS beads have great potential to be used as drug carriers for medical applications
Microscale Humidity Sensor Based on Iron-Coated Elaters of Equisetum Spores
No full textHumidity sensors deeply influence human manufacturing production and daily life, while researchers generally focus on developing humidity sensors with higher stability, higher linearity, rapid response time, etc. Yet, few people discuss measuring humidity in the microenvironment by miniaturizing sensor size into a microscale, in which the existing humidity sensors are difficult to reach. Accordingly, this study proposes a methodology for measuring relative humidity in the microscale by utilizing the distinctive morphologies of Equisetum spores across a range of relative humidities between 50% and 90%. Equisetum spores are responsive to changes in ambient relative humidity and remain in their original activities even after iron sputtering, which aims to endow the sensor with magnetic properties. The test performed in this study demonstrated a response time of 3.3 s and a recovery time of 3.6 s. In the first application, we employed such microscale sensors to work in the channel of the microfluidic chip or the cell migration microchip, as an example of working in the microenvironment. COMSOL Multiphysics 6.2 software was also used to simulate the change in relative humidity in such microchannels. Secondly, such microscale sensors are combined with smartphone-based microscopy to measure the humidity of the skin. These microscale sensors pave the new way to sensing humidity in microenvironments
Engineering pulp foam with highly improved water stability and multifunctional properties by incorporation of natural rubber and montmorillonite
No full textConsidering the aim of carbon neutrality and reducing plastic pollution, lightweight porous materials with good thermal insulation and mechanical robustness derived from renewable resources are in high demand. Cellulose-based pulp foams (PFs) offer considerable potential applications in many fields; however, the cost-effective manufacturing of PFs with satisfactory properties remains challenging. Herein, we demonstrate a simple and low-cost strategy to prepare a novel pulp/natural rubber (PNR) foam by combining wood pulp fiber and natural rubber latex through wet foaming and oven drying, eliminating traditional freeze-drying and solvent exchange processes. The obtained PNR foam exhibited high porosity (98.4%-99.1%), low density (14.1–24.0 mg/cm3), and excellent water stability (without disintegration under magnetic stirring for 14 days). Moreover, montmorillonite (MMT) was easily incorporated into the PNR during the preparation process, improving the mechanical strength and heat insulation of the obtained PNR-MMT foam. The optimized PNR-MMT foam could be compressed more than ten times without losing its resilience, exhibiting a compressive strength of 2.7 MPa at 80% strain, five times higher than that of pristine PF. Moreover, the PNR-MMT foam exhibited excellent flame retardant, good “spill” oil absorption, and good antibacterial properties towards Escherichia coli and Bacillus subtilis. Overall, this study provides a facile, sustainable, and low-cost route for manufacturing PNR-MMT foams with high resilience, good thermal insulation, excellent flame retardancy, and strong antibacterial properties, thus highlighting their usage potential in a broad range of applications
Long-term efficacy and safety of tenofovir alafenamide, tenofovir disoproxil fumarate, and entecavir in treating hepatitis B virus-related acute-on-chronic liver failure: A 144-week data analysis
No full textBackground and aims: Antiviral therapy is essential for hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF). No data are available on the long-term prognosis or safety of tenofovir alafenamide (TAF), tenofovir disoproxil fumarate (TDF), or entecavir (ETV) in treating HBV-ACLF globally. This study was conducted to investigate the long-term efficacy and safety of the three nucleos(t)ide analogs in the treatment of HBV-ACLF. Methods: In this prospective, real-world cohort study, patients with HBV-ACLF were assigned to the TAF, TDF, and ETV groups. A total of 199 patients completed the 144-week follow-up. After propensity score matching (PSM), 44 patients remained in each group for further analysis of survival status, incidence of hepatocellular carcinoma (HCC), virological response, and liver and renal function indicators. Results: In the original cohort, HCC developed in one patient in each group. No serious drug-related adverse events were observed. In the PSM cohort, the 144-week survival rates were 56.82%, 75.00%, and 59.09% in the TAF, TDF, and ETV groups, respectively (P = 0.118). When stratified into noncirrhosis and cirrhosis subgroups at baseline, the survival rate of the ETV group was slightly lower than that of the TAF and TDF group in noncirrhosis patients (P = 0.338), and the survival rate of the TAF group was slightly lower than that of the TDF and ETV group in cirrhosis patients (P = 0.052), but the differences were not statistically significant. The long-term overall survival rates in the TAF, TDF, and ETV groups were comparable. After 144 weeks, no significant difference in the virological response rate or liver or renal function indicators was found among the three groups, except for the level of aspartate aminotransferase, which was significantly higher in the TDF group than in the ETV group at week 144 (P = 0.001). Conclusions: There were no significant differences in the survival rate, incidence of HCC, efficacy or safety associated with the use of these three nucleos(t)ide analogs in treating HBV-ACLF. Trial registration: ClinicalTrials.gov NCT03920618
Efficacy and safety of artificial liver support system treatment for immune checkpoint inhibitors related liver failure in patients with hepatocellular carcinoma: Protocol for a randomized controlled clinical trial
No full textBackground: Immune checkpoint inhibitor-induced immune-mediated hepatitis (ICI-IMH) in patients with hepatocellular carcinoma (HCC) has been established to increase the risk of liver failure (LF). Given the accumulating evidence supporting the efficacy of artificial liver support systems (ALSS) in mitigating both IMH and LF, a single-center, non-blinded, randomized controlled clinical trial is proposed to investigate the efficacy and safety of ALSS for HCC patients with ICI-LF. Methods: and analysis: Sixty eligible participants will be enrolled in this trial and randomly assigned to one of two groups in a 1:1 ratio. In addition to standard pharmacological management, patients in the trial group will receive treatment with a double plasma molecular adsorption system (DPMAS) and low-volume plasma exchange (LPE) on three occasions, while patients in the control group will undergo PE three times. Patient assessments, including symptoms and laboratory tests, will be conducted at baseline, before and after the three ALSS treatments, and at 2, 4, 8, and 12 weeks post-enrollment. The primary outcome is the mortality rate at 12-week follow-up. Secondary outcomes include changes in the Model for End-Stage Liver Disease (MELD) score following ALSS treatment and the incidence of adverse events (AEs). Discussion: ICI-LF in HCC patients is associated with a high mortality rate and lacks effective treatment options. Our study aims to evaluate the efficacy and safety of ALSS for this patient population, comparing the effectiveness of two ALSS modalities (DPMAS + LPE vs. PE). Trial registration: This clinical trial has been registered on ClinicalTrials.gov with the identifier NCT05484908 (Release Date: July 30, 2022) (https://clinicaltrials.gov/study/NCT05484908)
Robust, Scalable, and Cost-Effective Surface Carbonized Pulp Foam for Highly Efficient Solar Steam Generation
No full textRecently,
a solar-driven evaporator has been applied in seawater
desalination, but the low stability, high cost, and complex fabrication
limit its further application. Herein, we report a novel, low-cost,
scalable, and easily fabricated pulp-natural rubber (PNR) foam with
a unique porous structure, which was directly used as a solar-driven
evaporator after facile surface carbonization. This surface carbonized
PNR (CPNR) foam without interface adhesion or modification was composed
of a top photothermal layer with light absorption ability and a bottom
hydrophilic foam layer with a porous and interconnected network structure.
Due to the strong light absorption ability (93.2%) of the carbonized
top layer, together with the low thermal conductivity (0.1 W m K–1) and good water adsorption performance (9.9 g g–1) of the bottom layer, the evaporation rate and evaporation
efficiency of the pulp foam evaporator under 1 sun of illumination
attained 1.62 kg m–2 h–1 and 98.09%,
respectively, which were much higher than those of most cellulose-based
solar-driven evaporators. Furthermore, the CPNR foam evaporator with
high cost-effectiveness presented high light-thermal conversion, heat
localization, and good salt rejection properties due to the unique
porous structure. Additionally, the CPNR foam evaporator exhibited
potential applications in the treatments of simulated sewage, metal
ion concentration, and seawater desalination. Its cost-effectiveness
was clearly higher than that of most reported evaporators as well.
Therefore, this novel, low-cost, and stable pulp foam evaporator demonstrated
here can be a very promising solution for water desalination and purification
Robust, Scalable, and Cost-Effective Surface Carbonized Pulp Foam for Highly Efficient Solar Steam Generation
No full textRecently,
a solar-driven evaporator has been applied in seawater
desalination, but the low stability, high cost, and complex fabrication
limit its further application. Herein, we report a novel, low-cost,
scalable, and easily fabricated pulp-natural rubber (PNR) foam with
a unique porous structure, which was directly used as a solar-driven
evaporator after facile surface carbonization. This surface carbonized
PNR (CPNR) foam without interface adhesion or modification was composed
of a top photothermal layer with light absorption ability and a bottom
hydrophilic foam layer with a porous and interconnected network structure.
Due to the strong light absorption ability (93.2%) of the carbonized
top layer, together with the low thermal conductivity (0.1 W m K–1) and good water adsorption performance (9.9 g g–1) of the bottom layer, the evaporation rate and evaporation
efficiency of the pulp foam evaporator under 1 sun of illumination
attained 1.62 kg m–2 h–1 and 98.09%,
respectively, which were much higher than those of most cellulose-based
solar-driven evaporators. Furthermore, the CPNR foam evaporator with
high cost-effectiveness presented high light-thermal conversion, heat
localization, and good salt rejection properties due to the unique
porous structure. Additionally, the CPNR foam evaporator exhibited
potential applications in the treatments of simulated sewage, metal
ion concentration, and seawater desalination. Its cost-effectiveness
was clearly higher than that of most reported evaporators as well.
Therefore, this novel, low-cost, and stable pulp foam evaporator demonstrated
here can be a very promising solution for water desalination and purification
