We propose an experimentally feasible method for enhancing the atom-field coupling as well as the ratio between this coupling and dissipation (i.e., cooperativity) in an optical cavity. It exploits ...optical parametric amplification to exponentially enhance the atom-cavity interaction and, hence, the cooperativity of the system, with the squeezing-induced noise being completely eliminated. Consequently, the atom-cavity system can be driven from the weak-coupling regime to the strong-coupling regime for modest squeezing parameters, and even can achieve an effective cooperativity much larger than 100. Based on this, we further demonstrate the generation of steady-state nearly maximal quantum entanglement. The resulting entanglement infidelity (which quantifies the deviation of the actual state from a maximally entangled state) is exponentially smaller than the lower bound on the infidelities obtained in other dissipative entanglement preparations without applying squeezing. In principle, we can make an arbitrarily small infidelity. Our generic method for enhancing atom-cavity interaction and cooperativities can be implemented in a wide range of physical systems, and it can provide diverse applications for quantum information processing.
Bovine mycoplasmosis is an important infectious disease of cattle caused by
(
) which poses a serious threat to the breeding industry. Adhesin is involved in the initial process of
colonization, ...which is closely related to the infection, cell invasion, immune escape and virulence of this pathogenic microorganism. For the reason that
lacks a cell wall, its adhesin is predominantly located on the surface of the cell membrane. The adhesins of
are usually identified by adhesion and adhesion inhibition analysis, and more than 10 adhesins have been identified so far. These adhesins primarily bind to plasminogen, fibronectin, heparin and amyloid precursor-like protein-2 of host cells. This review aims to concisely summarize the current knowledge regarding the adhesins of
and their target proteins of the host cell. Additionally, the biological characteristics of the adhesin will be briefly analyzed.
Using a distinguishable-particle lattice model based on void-induced dynamics, we successfully reproduce the well-known linear relation between heat capacity and temperature at very low temperatures. ...The heat capacity is dominated by two-level systems formed due to the strong localization of voids to two neighboring sites, and can be exactly calculated in the limit of ultrastable glasses. Similar but weaker localization at higher temperatures accounts for glass transition. The result supports the conventional two-level tunneling picture by revealing how two-level systems emerge from random particle interactions, which also cause glass transition. Our approach provides a unified framework for relating microscopic dynamics of glasses at room and cryogenic temperatures.
By applying a distinguishable-particle lattice model previously demonstrated to exhibit glassy relaxation dynamics, we observe the emergence of two-level systems at very low temperature leading to a specific heat proportional to the temperature.
The tensile properties and deformed microstructures of Ti–5Al–1V–1Sn–1Zr-0.8Mo (Ti5111) alloy with a bimodal structure under different deformation temperatures are investigated. As the deformation ...temperature decreases from 0 °C to −196 °C, the tensile strength, and elongation of Ti5111 increase simultaneously. The distinguishing characteristic of the deformed structure is the presence of {101‾2}101‾1 deformation twins (DTs) at −196 °C. These DTs can improve the tensile elongation by twinning-induced plasticity (TWIP), and make additional grains amenable for dislocation slip by changing the local microstructure orientation, promoting homogeneous deformation and contribute toward a higher elongation at −196 °C than that at 0 °C. The enhanced tensile strength at −196 °C is attributed to the coupling influence of the higher stress of dislocation slip at cryogenic temperature and the deformation twins-induced grain refinement.
•Enhancement cryogenic tensile strength and elongation for Ti5111 was reported.•Enhancement cryogenic tensile strength and elongation attributed to the activation of DTs.•DTs may modify the hard orientation amenable for slip and refine the microstructure size.
Abstract
Hybridizing collective spin excitations and a cavity with high cooperativity provides a new research subject in the field of cavity quantum electrodynamics and can also have potential ...applications to quantum information. Here we report an experimental study of cavity quantum electrodynamics with ferromagnetic magnons in a small yttrium-iron-garnet (YIG) sphere at both cryogenic and room temperatures. We observe for the first time a strong coupling of the same cavity mode to both a ferromagnetic-resonance (FMR) mode and a magnetostatic (MS) mode near FMR in the quantum limit. This is achieved at a temperature ~22 mK, where the average microwave photon number in the cavity is less than one. At room temperature, we also observe strong coupling of the cavity mode to the FMR mode in the same YIG sphere and find a slight increase of the damping rate of the FMR mode. These observations reveal the extraordinary robustness of the FMR mode against temperature. However, the MS mode becomes unobservable at room temperature in the measured transmission spectrum of the microwave cavity containing the YIG sphere. Our numerical simulations show that this is due to a drastic increase of the damping rate of the MS mode.
IMPORTANCE: Among all subtypes of breast cancer, triple-negative breast cancer has a relatively high relapse rate and poor outcome after standard treatment. Effective strategies to reduce the risk of ...relapse and death are needed. OBJECTIVE: To evaluate the efficacy and adverse effects of low-dose capecitabine maintenance after standard adjuvant chemotherapy in early-stage triple-negative breast cancer. DESIGN, SETTING, AND PARTICIPANTS: Randomized clinical trial conducted at 13 academic centers and clinical sites in China from April 2010 to December 2016 and final date of follow-up was April 30, 2020. Patients (n = 443) had early-stage triple-negative breast cancer and had completed standard adjuvant chemotherapy. INTERVENTIONS: Eligible patients were randomized 1:1 to receive capecitabine (n = 222) at a dose of 650 mg/m2 twice a day by mouth for 1 year without interruption or to observation (n = 221) after completion of standard adjuvant chemotherapy. MAIN OUTCOMES AND MEASURES: The primary end point was disease-free survival. Secondary end points included distant disease-free survival, overall survival, locoregional recurrence-free survival, and adverse events. RESULTS: Among 443 women who were randomized, 434 were included in the full analysis set (mean SD age, 46 9.9 years; T1/T2 stage, 93.1%; node-negative, 61.8%) (98.0% completed the trial). After a median follow-up of 61 months (interquartile range, 44-82), 94 events were observed, including 38 events (37 recurrences and 32 deaths) in the capecitabine group and 56 events (56 recurrences and 40 deaths) in the observation group. The estimated 5-year disease-free survival was 82.8% in the capecitabine group and 73.0% in the observation group (hazard ratio HR for risk of recurrence or death, 0.64 95% CI, 0.42-0.95; P = .03). In the capecitabine group vs the observation group, the estimated 5-year distant disease-free survival was 85.8% vs 75.8% (HR for risk of distant metastasis or death, 0.60 95% CI, 0.38-0.92; P = .02), the estimated 5-year overall survival was 85.5% vs 81.3% (HR for risk of death, 0.75 95% CI, 0.47-1.19; P = .22), and the estimated 5-year locoregional recurrence-free survival was 85.0% vs 80.8% (HR for risk of locoregional recurrence or death, 0.72 95% CI, 0.46-1.13; P = .15). The most common capecitabine-related adverse event was hand-foot syndrome (45.2%), with 7.7% of patients experiencing a grade 3 event. CONCLUSIONS AND RELEVANCE: Among women with early-stage triple-negative breast cancer who received standard adjuvant treatment, low-dose capecitabine maintenance therapy for 1 year, compared with observation, resulted in significantly improved 5-year disease-free survival. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01112826
A severe dust storm event originated from the Gobi Desert in Central and East
Asia during 2–7 May 2017. Based on Moderate Resolution Imaging
Spectroradiometer (MODIS) satellite products, hourly ...environmental monitoring
measurements from Chinese cities and East Asian meteorological observation
stations, and numerical simulations, we analysed the spatial and temporal
characteristics of this dust event as well as its associated impact on the
Asia-Pacific region. The maximum observed hourly PM10 (particulate
matter with an aerodynamic diameter ≤ 10 µm) concentration
was above 1000 µg m−3 in Beijing, Tianjin, Shijiazhuang,
Baoding, and Langfang and above 2000 µg m−3 in Erdos, Hohhot,
Baotou, and Alxa in northern China. This dust event affected over
8.35 million km2, or 87 % of the Chinese mainland, and significantly deteriorated air quality in 316 cities of
the 367 cities examined across China. The maximum surface wind speed during
the dust storm was 23–24 m s−1 in the Mongolian Gobi Desert and
20–22 m s−1 in central Inner Mongolia, indicating the potential
source regions of this dust event. Lidar-derived vertical dust profiles in
Beijing, Seoul, and Tokyo indicated dust aerosols were uplifted to an
altitude of 1.5–3.5 km, whereas simulations by the Weather Research and
Forecasting with Chemistry (WRF-Chem) model indicated 20.4 and 5.3 Tg of
aeolian dust being deposited respectively across continental Asia and the
North Pacific Ocean. According to forward trajectory analysis by the FLEXible
PARTicle dispersion (FLEXPART) model, the East Asian dust plume moved across
the North Pacific within a week. Dust concentrations decreased from the East
Asian continent across the Pacific Ocean from a magnitude of 103 to
10−5 µg m−3, while dust deposition intensity ranged from
104 to 10−1 mg m−2. This dust event was unusual due to its
impact on continental China, the Korean Peninsula, Japan, and the North
Pacific Ocean. Asian dust storms such as those observed in early May 2017 may
lead to wider climate forcing on a global scale.
Background and purpose
Migraine is a complex and disabling neurological disorder, the exact neurological mechanisms of which remain unclear. The thalamus is considered to be the hub of the central ...processing and integration of nociceptive information, as well as the modulation of these processes.
Methods
A total of 48 migraineurs without aura (MWoAs) during the interictal phase and 48 age‐ and sex‐matched healthy controls underwent resting‐state functional magnetic resonance imaging scans. We utilized masked independent component analysis and seed‐based functional connectivity (FC) to investigate whether MWoAs exhibited abnormal FC between subregions in the thalamus and the cortex regions.
Results
The MWoAs showed significantly weaker FC between the anterior dorsal thalamic nucleus and left precuneus. Additionally, MWoAs exhibited significantly reduced FC between the ventral posterior nucleus (VPN) and left precuneus, right inferior parietal lobule (R‐IPL) and right middle frontal gyrus. Furthermore, the FC Z‐scores between the VPN and R‐IPL were negatively correlated with pain intensity in MWoAs. The disease duration of patients was negatively correlated with the FC Z‐scores between the VPN and R‐IPL.
Conclusion
These altered thalamocortical connectivity patterns may contribute to multisensory integration abnormalities, deficits in pain attention, cognitive evaluation and pain modulation. Pain sensitivity and disease duration are closely tied to abnormal FC between the VPN and R‐IPL. Remarkably, recurrent headache attacks might contribute to this maladaptive functional plasticity closely related to pain intensity.
Pituitary tumor-transforming gene-1 (PTTG1) is a proto-oncogene that promotes tumorigenesis and metastasis in numerous cell types and is overexpressed in a variety of human tumors. We have ...demonstrated that PTTG1 expression was up-regulated in both human prostate cancer specimens and prostate cancer cell lines. For a more direct assessment of the function of PTTG1 in prostate tumorigenesis, RNAi-mediated knockdown was used to selectively decrease PTTG1 expression in PC3 human prostate tumor cells. After three weeks of selection, colonies stably transfected with PTTG1-targeted RNAi (the knockdown PC3 cell line) or empty vector (the control PC3 cell line) were selected and expanded to investigate the role of PTTG1 expression in PC3 cell growth and invasion. Cell proliferation rate was significantly slower (28%) in the PTTG1 knockdown line after 6 days of growth as indicated by an MTT cell viability assay (P < 0.05). Similarly, a soft agar colony formation assay revealed significantly fewer (66.7%) PTTG1 knockdown PC3 cell colonies than control colonies after three weeks of growth. In addition, PTTG1 knockdown resulted in cell cycle arrest at G1 as indicated by fluorescence-activated cell sorting. The PTTG1 knockdown PC3 cell line also exhibited significantly reduced migration through Matrigel in a transwell assay of invasive potential, and down-regulation of PTTG1 could lead to increased sensitivity of these prostate cancer cells to a commonly used anticancer drug, taxol. Thus, PTTG1 expression is crucial for PC3 cell proliferation and invasion, and could be a promising new target for prostate cancer therapy.
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