ABSTRACT
The collision reaction of H + O2 = OH + O is a pivotal step in combustion. To investigate the influence of singlet oxygen on this reaction, we computed potential energy surfaces (PESs) for all six lowest states using high-level ab initio methods and coupled them with embedded atom neural network (EANN) fitting. By integrating quasi-classical trajectory (QCT) with trajectory surface hopping (TSH) based on the fitted PESs, we simulated the dynamics of both ground- and excited-states to derive the reaction rate constants for the forward and reverse processes. The results reveal that the forward reaction facilitates radical generation, promoting combustion reactions. Furthermore, calculations of reverse reaction rate constants indicate that all electronic states ultimately yield ground-state oxygen, leading to radical deactivation and exerting an inhibitory effect on combustion processes.
ABSTRACT
Radical-radical reactions can generate two channels with high and low spins. In this work, ten radical-radical reactions with different spin channels and four radical-molecule reactions in hydrogen-oxygen combustion were systematically investigated from a theoretical perspective. The potential energy surface (PES) of radical-radical reactions reveals that the high- and low-spin states of the reactant are energetically degenerate and the two channels are energetically feasible. The difference in rate constants between the high- and low-spin channels gradually decreases as the temperature increases. Then, the kinetic parameters of the 14 bimolecular reactions in the hydrogen-oxygen mechanism of the University of California, San Diego (UCSD), were replaced to simulate the ignition delay time and laminar flame speed. The simulation results agree well with the available experimental findings, indicating the necessity of considering both high- and low-spin channels for kinetic simulation.
ABSTRACT
Type 2 alveolar epithelial cell (AEC2) senescence is crucial to the pathogenesis of pulmonary fibrosis (PF). The nicotinamide adenine dinucleotide (NAD+)-consuming enzyme cluster of differentiation 38 (CD38) is a marker of senescent cells and is highly expressed in AEC2s of patients with PF, thus rendering it a potential treatment target. Umbilical cord mesenchymal stem cell (MSC)-derived extracellular vesicles (MSC-EVs) have emerged as a cell-free treatment with clinical application prospects in antiaging and antifibrosis treatments. Herein, we constructed CD38 antigen receptor membrane-modified MSC-EVs (CD38-ARM-MSC-EVs) by transfecting MSCs with a lentivirus loaded with a CD38 antigen receptor-CD8 transmembrane fragment fusion plasmid to target AEC2s and alleviate PF. Compared with MSC-EVs, the CD38-ARM-MSC-EVs engineered in this study showed a higher expression of the CD38 antigen receptor and antifibrotic miRNAs and targeted senescent AEC2s cells highly expressing CD38 in vitro and in naturally aged mouse models after intraperitoneal administration. CD38-ARM-MSC-EVs effectively restored the NAD+ levels, reversed the epithelial-mesenchymal transition phenotype, and rejuvenated senescent A549 cells in vitro, thereby mitigating multiple age-associated phenotypes and alleviating PF in aged mice. Thus, this study provides a technology to engineer MSC-EVs and support our CD38-ARM-MSC-EVs to be developed as promising agents with high clinical potential against PF.
Subject(s)
Extracellular Vesicles , Mesenchymal Stem Cells , Pulmonary Fibrosis , Humans , Mice , Animals , Pulmonary Fibrosis/therapy , Pulmonary Fibrosis/metabolism , Alveolar Epithelial Cells , NAD/metabolism , Extracellular Vesicles/metabolism , Receptors, Antigen/metabolismABSTRACT
Cold atoms in an optical cavity have been widely used for quantum simulations of many-body physics, where the quantum control capability has been advancing rapidly in recent years. Here, we show the atom cavity system is universal for quantum optimization with arbitrary connectivity. We consider a single-mode cavity and develop a Raman coupling scheme by which the engineered quantum Hamiltonian for atoms directly encodes number partition problems. The programmability is introduced by placing the atoms at different positions in the cavity with optical tweezers. The number partition problem solution is encoded in the ground state of atomic qubits coupled through a photonic cavity mode, which can be reached by adiabatic quantum computing. We construct an explicit mapping for the 3-SAT and vertex cover problems to be efficiently encoded by the cavity system, which costs linear overhead in the number of atomic qubits. The atom cavity encoding is further extended to quadratic unconstrained binary optimization problems. The encoding protocol is optimal in the cost of atom number scaling with the number of binary degrees of freedom of the computation problem. Our theory implies the atom cavity system is a promising quantum optimization platform searching for practical quantum advantage.
ABSTRACT
Cancer heterogeneity has posed great challenges in exploring precise therapeutic strategies for cancer treatment. The identification of cancer subtypes aims to detect patients with distinct molecular profiles and thus could provide new clues on effective clinical therapies. While great efforts have been made, it remains challenging to develop powerful computational methods that can efficiently integrate multi-omics datasets for the task. In this paper, we propose a novel self-supervised learning model called Deep Multi-view Contrastive Learning (DMCL) for cancer subtype identification. Specifically, by incorporating the reconstruction loss, contrastive loss and clustering loss into a unified framework, our model simultaneously encodes the sample discriminative information into the extracted feature representations and well preserves the sample cluster structures in the embedded space. Moreover, DMCL is an end-to-end framework where the cancer subtypes could be directly obtained from the model outputs. We compare DMCL with eight alternatives ranging from classic cancer subtype identification methods to recently developed state-of-the-art systems on 10 widely used cancer multi-omics datasets as well as an integrated dataset, and the experimental results validate the superior performance of our method. We further conduct a case study on liver cancer and the analysis results indicate that different subtypes might have different responses to the selected chemotherapeutic drugs.
Subject(s)
Liver Neoplasms , Humans , Liver Neoplasms/genetics , Cluster Analysis , MultiomicsABSTRACT
The large-scale implementations of lithium iron phosphate (LFP) batteries for energy storage systems have been gaining attention around the world due to their quality of high technological maturity and flexible configuration. Unfortunately, the exponential production of LFP batteries is accompanied by an annual accumulation of spent batteries and a premature consumption of the lithium resource. Recycling souring critical battery materials such as Li2CO3 is essential to reduce the supply chain risk and achieve net carbon neutrality goals. During the recovery of Li2CO3, impurity removal is the most crucial step in the hydrometallurgy process of spent LiFePO4, which determines the purity of Li2CO3. By investigating and comparing the results of impurity elimination from the purified Li+-containing liquids with strong and weak alkalis under identical pH conditions, respectively, a strategy based on an alkali mixture has been proposed. The purified Li+-containing liquid was, thereafter, concentrated and sodium carbonate was added in order to precipitate Li2CO3. As a result, a high purity Li2CO3 (99.51%) of battery grade was obtained. LiFePO4 prepared with the recovered Li2CO3 and FePO4 as raw materials also displayed a comparative high capacity and stable cycle performance to the commercial product and further verified the electrochemical activity of the recovered materials.
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Background: To curb the spread of the coronavirus disease 2019 (COVID-19) epidemic, the Chinese government shut down Wuhan city from January 23rd to April 8th, 2020. The COVID-19 epidemic not only leads to widespread illness but also affects the diagnosis and treatment of hematopoietic stem-cell transplant (HSCT) recipients. Objective: To investigate the medical-seeking pattern and daily behavior changes in Hubei Province during the COVID-19 epidemic in Hubei Province during the lockdown. Methods: We conducted a multicenter, cross-sectional, web-based investigation among 325 HSCT recipients by online questionnaires in Hubei Province during the COVID-19 epidemic. Results: A total of 145 complete responses were collected both before and during the epidemic questionnaires. The participants from pre-epidemic group preferred to go to hospital (68.29%) when they experienced influenza-like symptoms. The majority of the patients elected to take oral drugs by themselves (40%) or consulted their attending physicians online or by telephone during the lockdown (23.33%). 64.83% had difficulties in purchasing drugs during the lockdown, which was significantly higher than the proportion of the pre-epidemic group (24.83%) (P < 0.05). The participants preferred to purchase drugs online (23.40%) and decrease or withdraw drugs (18.09%) during the epidemic. The number of participants received regular re-examinations during the epidemic decreased sharply. The proportion of wearing masks and isolating themselves at home increased significantly during the epidemic. No statistic difference was observed in the incidence of graft-versus-host disease (GVHD)complications in participants between the during the epidemic group and the pre-epidemic group. In our study, six patients were confirmed to have COVID-19, and half of them died due to COVID-19-related complications. Conclusion: The medical-seeking pattern and daily behavior of HSCT recipients changed during the lockdown; the methods of self-protection, online consultation and drug delivery can help patients receive necessary follow-up and reduce the occurrence of COVID-19.
Subject(s)
COVID-19 , Hematopoietic Stem Cell Transplantation , Humans , COVID-19/epidemiology , SARS-CoV-2 , Transplant Recipients , Cross-Sectional Studies , Communicable Disease Control , China/epidemiology , Surveys and QuestionnairesABSTRACT
A quantum gas microscope plays an important role in cold-atom experiments, which provides a high-resolution imaging of the spatial distributions of cold atoms. Here we design, build and calibrate an integrated microscope for quantum gases with all the optical components fixed outside the vacuum chamber. It provides large numerical aperture (NA) of 0.75, as well as good optical access from side for atom loading in cold-atom experiments due to long working distance (7 mm fused silica+6 mm vacuum) of the microscope objective. We make a special design of the vacuum viewport with a T-shape window, to suppress the window flatness distortion introduced by the metal-glass binding process, and protect the high-resolution imaging from distortions due to unflattened window. The achieved Strehl ratio is 0.9204 using scanning-near-field microscopy (SNOM) fiber coupling incoherent light as point light source.
ABSTRACT
MYH9-related disorder (MYH9-RD) is autosomal dominant thrombocytopenia caused by mutations in the MYH9 gene, which codes for the non-muscle myosin-IIA heavy chain. We present a case of a 24-year-old Chinese man with MYH9-RD who was initially misdiagnosed with immune thrombocytopenia. Whole-exome sequencing and Sanger sequencing revealed a novel missense mutation in the MYH9 gene at the position of c.4550 G > T (p.G1517V) in exon 32. The same phenotype was observed in the proband, his mother, and his brother, in addition to macrothrombocytopenia and Dohle-like bodies in neutrophil granulocytes without non-hematologic manifestations. Following failed treatment with eltrombopag, avatrombopag, which was not mentioned before in the MYH9-RD treatment, was administered to the patient, and thrombocytopenia improved. In this case report, we present a novel pathogenic mutation and show the potential of avatrombopag for temporarily increasing the platelet count in patients with MYH9-RD.
Subject(s)
Hearing Loss, Sensorineural , Thrombocytopenia , Benzoates , Hearing Loss, Sensorineural/genetics , Humans , Hydrazines , Male , Molecular Motor Proteins/genetics , Mutation , Myosin Heavy Chains/genetics , Pyrazoles , Thiazoles , Thiophenes , Thrombocytopenia/congenital , Thrombocytopenia/diagnosis , Thrombocytopenia/drug therapy , Thrombocytopenia/genetics , Treatment FailureABSTRACT
Few therapies can reverse the proangiogenic activity of senescent mesenchymal stromal/stem cells (MSCs). In this study, we investigated the effects of rapamycin on the proangiogenic ability of senescent human umbilical cord MSCs (UCMSCs). An in vitro replicative senescent cell model was established in cultured UCMSCs. We found that late passage (P25 or later) UCMSCs (LP-UCMSCs) exhibited impaired proangiogenic abilities. Treatment of P25 UCMSCs with rapamycin (900 nM) reversed the senescent phenotype and notably enhanced the proangiogenic activity of senescent UCMSCs. In a nude mouse model of hindlimb ischemia, intramuscular injection of rapamycin-treated P25 UCMSCs into the ischemic limb significantly promoted neovascularization and ischemic limb salvage. We further analyzed the changes in the expression of angiogenesis-associated genes in rapamycin-primed MSCs and found higher expression of several genes related to angiogenesis, such as VEGFR2 and CTGF/CCN2, in primed cells than in unprimed MSCs. Taken together, our data demonstrate that rapamycin is a potential drug to restore the proangiogenic activity of senescent MSCs, which is of importance in treating ischemic diseases and tissue engineering.
Subject(s)
Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Humans , Mice , Animals , Limb Salvage , Hindlimb , Neovascularization, Physiologic , Sirolimus/pharmacology , Sirolimus/therapeutic use , Ischemia/therapy , Ischemia/metabolism , Mesenchymal Stem Cells/metabolism , Neovascularization, Pathologic/metabolism , Mice, Nude , Cells, CulturedABSTRACT
We observe and study a special ground state of bosons with two spin states in an optical lattice: the spin-Mott insulator, a state that consists of repulsively bound pairs that is insulating for both spin and charge transport. Because of the pairing gap created by the interaction anisotropy, it can be prepared with low entropy and can serve as a starting point for adiabatic state preparation. We find that the stability of the spin-Mott state depends on the pairing energy, and observe two qualitatively different decay regimes, one of which exhibits protection by the gap.
ABSTRACT
(1) Background: Although there are extensive data on admission co-variates and outcomes of persons with coronavirus infectious disease-2019 (COVID-19) at diverse geographic sites, there are few, if any, subject-level comparisons between sites in regions and countries. We investigated differences in hospital admission co-variates and outcomes of hospitalized people with COVID-19 between Wuhan City, China and the New York City region, USA. (2) Methods: We retrospectively analyzed clinical data on 1859 hospitalized subjects with COVID-19 in Wuhan City, China, from 20 January to 4 April 2020. Data on 5700 hospitalized subjects with COVID-19 in the New York City region, USA, from 1 March to 4 April 2020 were extracted from an article by Richardson et al. Hospital admission co-variates (epidemiological, demographic, and laboratory co-variates) and outcomes (rate of intensive care unit [ICU] admission, invasive mechanical ventilation [IMV], major organ failure and death, and length of hospital stay) were compared between the cohorts. (3) Results: Wuhan subjects were younger, more likely female, less likely to have co-morbidities and fever, more likely to have a blood lymphocyte concentration > 1 × 109/L, and less likely to have abnormal liver and cardiac function tests compared with New York subjects. There were outcomes data on all Wuhan subjects and 2634 New York subjects. Wuhan subjects had higher blood nadir median lymphocyte concentrations and longer hospitalizations, and were less likely to receive IMV, ICU hospitalization, and interventions for kidney failure. Amongst subjects not receiving IMV, those in Wuhan were less likely to die compared with New York subjects. In contrast, risk of death was similar in subjects receiving IMV at both sites. (4) Conclusions: We found different hospital admission co-variates and outcomes between hospitalized persons with COVID-19 between Wuhan City and the New York region, which should be useful developing a comprehensive global understanding of the SARS-CoV-2 pandemic and COVID-19.
ABSTRACT
Ramping a physical parameter is one of the most common experimental protocols in studying a quantum system, and ramping dynamics has been widely used in preparing a quantum state and probing physical properties. Here, we present a novel method of probing quantum many-body correlation by ramping dynamics. We ramp a Hamiltonian parameter to the same target value from different initial values and with different velocities, and we show that the first-order correction on the finite ramping velocity is universal and path-independent, revealing a novel quantum many-body correlation function of the equilibrium phases at the target values. We term this method as the non-adiabatic linear response since this is the leading order correction beyond the adiabatic limit. We demonstrate this method experimentally by studying the Bose-Hubbard model with ultracold atoms in three-dimensional optical lattices. Unlike the conventional linear response that reveals whether the quasi-particle dispersion of a quantum phase is gapped or gapless, this probe is more sensitive to whether the quasi-particle lifetime is long enough such that the quantum phase possesses a well-defined quasi-particle description. In the Bose-Hubbard model, this non-adiabatic linear response is significant in the quantum critical regime where well-defined quasi-particles are absent. And in contrast, this response is vanishingly small in both superfluid and Mott insulators which possess well-defined quasi-particles. Because our proposal uses the most common experimental protocol, we envision that our method can find broad applications in probing various quantum systems.
ABSTRACT
Quantum critical behavior of many-body phase transitions is one of the most fascinating yet challenging questions in quantum physics. Here, we improved the band-mapping method to investigate the quantum phase transition from superfluid to Mott insulators, and we observed the critical behaviors of quantum phase transitions in both the dynamical steady-state-relaxation region and the phase-oscillation region. Based on various observables, two different values for the same quantum critical parameter are observed. This result is beyond a universal-scaling-law description of quantum phase transitions known as the Kibble-Zurek mechanism, and suggests that multiple quantum critical mechanisms are competing in many-body quantum phase transition experiments in inhomogeneous systems.
ABSTRACT
Stem cell senescence increases alongside the progressive functional declines that characterize aging. The effects of extracellular vesicles (EVs) are now attracting intense interest in the context of aging and age-related diseases. Here, we demonstrate that neonatal umbilical cord (UC) is a source of EVs derived from mesenchymal stem cells (MSC-EVs). These UC-produced MSC-EVs (UC-EVs) contain abundant anti-aging signals and rejuvenate senescing adult bone marrow-derived MSCs (AB-MSCs). UC-EV-rejuvenated AB-MSCs exhibited alleviated aging phenotypes and increased self-renewal capacity and telomere length. Mechanistically, UC-EVs rejuvenate AB-MSCs at least partially by transferring proliferating cell nuclear antigen (PCNA) into recipient AB-MSCs. When tested in therapeutic context, UC-EV-triggered rejuvenation enhanced the regenerative capacities of AB-MSCs in bone formation, wound healing, and angiogenesis. Intravenously injected UC-EVs conferred anti-aging phenotypes including decreased bone and kidney degeneration in aged mice. Our findings reveal that UC-EVs are of high translational value in anti-aging intervention.
Subject(s)
Extracellular Vesicles , Mesenchymal Stem Cells , Animals , Bone Marrow , Cellular Senescence , Mice , Proliferating Cell Nuclear AntigenABSTRACT
Mixed phenotype acute leukemia (MPAL) is a rare hematological malignancy that lacks consensus on optimal management. We report for the first time two cases of treatment-naïve B/myeloid MPAL patients treated with a novel chemo-free regimen using venetoclax combined with hypomethylating agents, which successfully induced complete remission with tolerable toxicities.
ABSTRACT
Patients with hematological malignancies with immunodeficiency are at high risk for SARS-CoV-2 infection. We retrospective summarized clinical characteristics of coronavirus disease 2019 (COVID-19) inpatients with hematological malignancies, shared treatment experiences, and analysis prognostic factors. Fourteen patients were enrolled. The median duration of viral shedding was 27.5 days in survivors. The median duration of time to death was 13 days in non-survivors. Non-survivors tend to present lower neutrophil count, more imaging finding of bilateral diffuse patch opacities, more undergoing intensive chemotherapy or immunosuppression. Laboratory and image findings were atypical and diverse. COVID-19 inpatients undergoing intensive chemotherapy or immunosuppression might have increased risk of death. The diagnostic value of specific antibody detection is limited. Therefore, adult COVID-19 inpatients with hematological malignancies present atypical, severe symptoms, decreased virus clearance ability, abnormal antibody response and poor outcome. During the epidemic, the pros and cons need to be carefully weighed while selecting the treatment methods.
Subject(s)
COVID-19/prevention & control , Hematologic Neoplasms/therapy , Inpatients/statistics & numerical data , SARS-CoV-2/isolation & purification , Adolescent , Adult , Aged , COVID-19/epidemiology , COVID-19/virology , Female , Hematologic Neoplasms/diagnosis , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Outcome Assessment, Health Care/methods , Outcome Assessment, Health Care/statistics & numerical data , Prognosis , Retrospective Studies , Risk Factors , SARS-CoV-2/physiology , Young AdultABSTRACT
This study aimed to retrospectively evaluate the outcomes of adult patients with high-risk acute lymphoblastic leukemia (ALL) who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) with either total marrow and lymphoid irradiation (TMLI)-containing or non-TMLI conditioning regimen. Seventy adult patients with high-risk ALL who received allo-HSCT were enrolled in this study and divided into two groups based on the conditioning regimen type (TMLI group: n = 29 and non-TMLI group: n = 41). We noted significant statistical differences in the 1-year estimated cumulative incidence of relapse (25% vs. 46.5%, p = 0.018), the 1-year estimated overall survival (73.1% vs. 52.6%, p = 0.033) and disease-free survival (65.2% vs. 48.2%, p = 0.026) but found no considerable difference in transplant-related mortality (12% vs. 13.4%, p = 0.619) between patients in the TMLI and non-TMLI groups. The TMLI-containing regimen is safe and alternative for patients with high-risk ALL undergoing allo-HSCT.
Subject(s)
Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Adult , Bone Marrow , Graft vs Host Disease/epidemiology , Graft vs Host Disease/etiology , Humans , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Retrospective Studies , Transplantation ConditioningABSTRACT
The impact of cancer on outcome of persons with coronavirus disease 2019 (COVID-19) after infection with acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is controversial. We studied 1859 subjects with COVID-19 from seven centers in Wuhan, China, 65 of whom had cancer. We found having cancer was an independent risk factor for in-hospital death from COVID-19 in persons <65 years (hazard ratio [HR] = 2.45, 95% confidence interval [CI], 1.04, 5.76; P = 0.041) but not in those ≥65 years (HR = 1.12 [0.56, 2.24]; P = 0.740). It was also more common in those not in complete remission. Risks of in-hospital death were similar in subjects with solid cancers and those with hematological cancers. These data may help predict outcomes of persons with cancer and COVID-19.
Subject(s)
Coronavirus Infections/mortality , Neoplasms/complications , Pneumonia, Viral/mortality , Adult , Age Factors , Aged , Betacoronavirus , COVID-19 , China , Coronavirus Infections/complications , Female , Hospital Mortality , Humans , Male , Middle Aged , Neoplasms/mortality , Pandemics , Pneumonia, Viral/complications , Remission Induction , Risk Factors , SARS-CoV-2ABSTRACT
We studied 1859 subjects with confirmed COVID-19 from seven centers in Wuhan 1651 of whom recovered and 208 died. We interrogated diverse covariates for correlations with risk of death from COVID-19. In multi-variable Cox regression analyses increased hazards of in-hospital death were associated with several admission covariates: (1) older age (HR = 1.04; 95% Confidence Interval [CI], 1.03, 1.06 per year increase; P < 0.001); (2) smoking (HR = 1.84 [1.17, 2.92]; P = 0.009); (3) admission temperature per °C increase (HR = 1.32 [1.07, 1.64]; P = 0.009); (4) Log10 neutrophil-to-lymphocyte ratio (NLR; HR = 3.30 [2.10, 5.19]; P < 0.001); (5) platelets per 10 E + 9/L decrease (HR = 0.996 [0.994, 0.998]; P = 0.001); (6) activated partial thromboplastin (aPTT) per second increase (HR = 1.04 [1.02, 1.05]; P < 0.001); (7) Log10 D-dimer per mg/l increase (HR = 3.00 [2.17, 4.16]; P < 0.001); and (8) Log10 serum creatinine per µmol/L increase (HR = 4.55 [2.72, 7.62]; P < 0.001). In piecewise linear regression analyses Log10NLR the interval from ≥0.4 to ≤1.0 was significantly associated with an increased risk of death. Our data identify covariates associated with risk of in hospital death in persons with COVID-19.