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1.
Molecules ; 29(10)2024 May 08.
Article in English | MEDLINE | ID: mdl-38792061

ABSTRACT

Schisandra sphenanthera Rehd. et Wils., as a traditional Chinese medicine, has important medicinal value. In the market, the availability of the fruit of S. sphenanthera mainly relies on wild picking, but many canes and leaves are discarded during wild collection, resulting in a waste of resources. The canes and leaves of S. sphenanthera contain various bioactive ingredients and can be used as spice, tea, and medicine and so present great utilization opportunities. Therefore, it is helpful to explore the effective components and biological activities of the canes and leaves to utilize S. sphenanthera fully. In this study, the response surface method with ultrasound was used to extract the total triterpenoids from the canes and leaves of S. sphenanthera at different stages. The content of total triterpenoids in the leaves at different stages was higher than that in the canes. The total triterpenoids in the canes and leaves had strong antioxidant and antibacterial abilities. At the same time, the antibacterial activity of the total triterpenoids against Bacillus subtilis and Pseudomonas aeruginosa was stronger than that against Staphylococcus aureus and Escherichia coli. This study provides the foundation for the development and utilization of the canes and leaves that would relieve the shortage of fruit resources of S. sphenanthera.


Subject(s)
Anti-Bacterial Agents , Plant Extracts , Plant Leaves , Schisandra , Triterpenes , Schisandra/chemistry , Triterpenes/chemistry , Triterpenes/pharmacology , Triterpenes/isolation & purification , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Plant Leaves/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Antioxidants/pharmacology , Antioxidants/chemistry , Microbial Sensitivity Tests , Fruit/chemistry
2.
PeerJ ; 12: e17240, 2024.
Article in English | MEDLINE | ID: mdl-38685939

ABSTRACT

Background: Schisandra sphenanthera Rehd. et Wils. is a plant used in traditional Chinese medicine (TCM). However, great differences exist in the content of active secondary metabolites in various parts of S. sphenanthera. Do microorganisms critically influence the accumulation of active components in different parts of S. sphenanthera? Methods: In this study, 16S/ITS amplicon sequencing analysis was applied to unravel microbial communities in rhizospheric soil and different parts of wild S. sphenanthera. At the same time, the active secondary metabolites in different parts were detected, and the correlation between the secondary metabolites and microorganisms was analyzed. Results: The major components identified in the essential oils were sesquiterpene and oxygenated sesquiterpenes. The contents of essential oil components in fruit were much higher than that in stem and leaf, and the dominant essential oil components were different in these parts. The dominant components of the three parts were γ-muurolene, δ-cadinol, and trans farnesol (stem); α-cadinol and neoisolongifolene-8-ol (leaf); isosapathulenol, α-santalol, cedrenol, and longiverbenone (fruit). The microbial amplicon sequences were taxonomically grouped into eight (bacteria) and seven (fungi) different phyla. Community diversity and composition analyses showed that different parts of S. sphenanthera had similar and unique microbial communities, and functional prediction analysis showed that the main functions of microorganisms were related to metabolism. Moreover, the accumulation of secondary metabolites in S. sphenanthera was closely related to the microbial community composition, especially bacteria. In endophytic bacteria, Staphylococcus and Hypomicrobium had negative effects on five secondary metabolites, among which γ-muurolene and trans farnesol were the dominant components in the stem. That is, the dominant components in stems were greatly affected by microorganisms. Our results provided a new opportunity to further understand the effects of microorganisms on the active secondary metabolites and provided a basis for further research on the sustainable utilization of S. sphenanthera.


Subject(s)
Schisandra , Schisandra/metabolism , Schisandra/chemistry , Soil Microbiology , Microbiota/genetics , Oils, Volatile/metabolism , Secondary Metabolism , Plant Stems/microbiology , Plant Stems/metabolism , Sesquiterpenes/metabolism , Bacteria/genetics , Bacteria/classification , Bacteria/metabolism
3.
Phys Rev E ; 108(5-2): 055305, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38115448

ABSTRACT

We provide an algorithm, i-SPin 2, for evolving general spin-s Gross-Pitaevskii or nonlinear Schrödinger systems carrying a variety of interactions, where the 2s+1 components of the "spinor" field represent the different spin-multiplicity states. We consider many nonrelativistic interactions up to quartic order in the Schrödinger field (both short and long range, and spin-dependent and spin-independent interactions), including explicit spin-orbit couplings. The algorithm allows for spatially varying external and/or self-generated vector potentials that couple to the spin density of the field. Our work can be used for scenarios ranging from laboratory systems such as spinor Bose-Einstein condensates (BECs), to cosmological or astrophysical systems such as self-interacting bosonic dark matter. As examples, we provide results for two different setups of spin-1 BECs that employ a varying magnetic field and spin-orbit coupling, respectively, and also collisions of spin-1 solitons in dark matter. Our symplectic algorithm is second-order accurate in time, and is extensible to the known higher-order-accurate methods.

4.
Sci Total Environ ; 902: 166172, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37562633

ABSTRACT

The global sulfur limit regulation mandates the use of 0.5 % low sulfur fuel oil (LSFO) to reduce emissions of sulfur oxides (SOx), nitrogen oxides (NOx), and particulate matter (PM). However, the addition of naphthalene (Nap) to LSFO to stabilize its quality has led to an increase in polycyclic aromatic hydrocarbons (PAHs), with Nap being the main pollutant. This study investigates the effects of Nap in ship exhaust by analyzing the emission concentrations of volatile organic compounds (VOCs) and Nap in the exhaust of 16 ships, including 2 container ships, 6 bulk carriers, 1 tanker, 2 ferries, 3 fishing vessels, and 2 harbor crafts, based on USEPA method TO-15A. The results show that the percentage of Nap emissions in the exhaust gases of the 16 ship engines ranged from 77 % to 97 % of the total volatile organic compound (TVOC). The Nap concentration in the exhaust of fishing vessels, tanker, and harbor craft exceeded the occupational exposure limit of 50,000 µg/m3, with fishing vessels having the highest TVOC and Nap concentrations. The enhanced Nap emission in the air degrades air quality in port cities and poses an obvious potential public health risk. While the benefits of the global sulfur cap are being secured, additional efforts should be made to reduce the undetected side effects. Alternative stabilizers of LSFO should be considered, or Nap emission control should be boosted to mitigate the potential negative impact on harbor air quality.

5.
World J Pediatr ; 19(12): 1139-1148, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36973599

ABSTRACT

BACKGROUND: Antibiotics are widely prescribed among children and pregnant women, but their safety profile is controversial. This study aimed to summarize and appraise current evidence for the potential impact of antibiotic exposure on pregnancy outcomes and children's health. METHODS: PubMed, Embase, Web of Science and the Cochrane Database of Systematic Reviews were searched from inception to June 2022. Meta-analyses of any study design comparing the impact of antibiotic exposure with nonexposure among children, pregnant women and prepregnant women on adverse health outcomes of children and pregnancy were retrieved. The quality of evidence was assessed by a Measurement Tool to Assess Systematic Reviews 2 (AMSTAR2) and the Grading of Recommendations, Assessment, Development and Evaluation (GRADE). Data were reanalyzed, and the credibility of the evidence was determined. RESULTS: Out of 2956 studies identified, 19 articles with 39 associations were included. Totally 19 of the associations (48.72%) were statistically significant with a P value ≤ 0.05, while only six were supported by highly suggestive evidence. Children with postnatal antibiotic exposure had a higher risk of developing asthma odds ratio (OR): 1.95, 95% confidence interval (CI): 1.76-2.17, wheezing (OR: 1.81, 95% CI 1.65-1.97) and allergic rhinoconjunctivitis (OR: 1.66, 95% CI 1.51-1.83), with prediction intervals excluding the nulls. Quality assessed by both AMSTAR2 and GRADE of included meta-analyses were very low in general. CONCLUSIONS: Antibiotic exposure in early life was associated with children's long-term health, especially in cases of allergic diseases. Prenatal exposure might also influence children's health in some aspects but requires more high-quality evidence. Potential adverse effects of antibiotics on pregnancy outcomes were not observed in our study. Studies with higher quality and better quantification of antibiotic exposure are needed in the future.

6.
Sci Rep ; 13(1): 2526, 2023 Feb 13.
Article in English | MEDLINE | ID: mdl-36781905

ABSTRACT

Some of the most exotic properties of the quantum vacuum are predicted in ultrastrongly coupled photon-atom systems; one such property is quantum squeezing leading to suppressed quantum fluctuations of photons and atoms. This squeezing is unique because (1) it is realized in the ground state of the system and does not require external driving, and (2) the squeezing can be perfect in the sense that quantum fluctuations of certain observables are completely suppressed. Specifically, we investigate the ground state of the Dicke model, which describes atoms collectively coupled to a single photonic mode, and we found that the photon-atom fluctuation vanishes at the onset of the superradiant phase transition in the thermodynamic limit of an infinite number of atoms. Moreover, when a finite number of atoms is considered, the variance of the fluctuation around the critical point asymptotically converges to zero, as the number of atoms is increased. In contrast to the squeezed states of flying photons obtained using standard generation protocols with external driving, the squeezing obtained in the ground state of the ultrastrongly coupled photon-atom systems is resilient against unpredictable noise.

7.
Phys Rev Lett ; 129(18): 183602, 2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36374667

ABSTRACT

We map a quantum Rabi ring, consisting of N cavities arranged in a ring geometry, into an effective magnetic model containing the XY exchange and the Dzyaloshinskii-Moriya (DM) interactions. The analog of the latter is induced by an artificial magnetic field, which modulates photon hopping between nearest-neighbor cavities with a phase. This mapping facilitates the description and understanding of the different phases in the quantum optical model through simple arguments of competing magnetic interactions. For the square geometry (N=4) the rich phase diagram exhibits three superradiant phases denoted as ferro-superradiant, antiferro-superradiant, and chiral superradiant. In particular, the DM interaction is responsible for the chiral phase in which the energetically degenerate configurations of the order parameters are similar to the in-plane magnetizations of skyrmions with different helicities. The antiferro-superradiant phase is suppressed in the triangle geometry (N=3) as geometric frustration contributes to stabilize the chiral phase even for small values of the DM interaction. The chiral phases for odd and even N show a different scaling behavior close to the phase transition. The equivalent behavior on both systems opens the possibility of simulating chiral magnetism in a few-body quantum optical platform, as well as understanding one system using the insights gained from the other.

8.
Science ; 376(6599): 1305-1308, 2022 06 17.
Article in English | MEDLINE | ID: mdl-35709259

ABSTRACT

Ultracold atoms confined to periodic potentials have proven to be a powerful tool for quantum simulation of complex many-body systems. We confine fermions to one dimension to realize the Tomonaga-Luttinger liquid model, which describes the highly collective nature of their low-energy excitations. We use Bragg spectroscopy to directly excite either the spin or charge waves for various strengths of repulsive interaction. We observe that the velocity of the spin and charge excitations shift in opposite directions with increasing interaction, a hallmark of spin-charge separation. The excitation spectra are in quantitative agreement with the exact solution of the Yang-Gaudin model and the Tomonaga-Luttinger liquid theory. Furthermore, we identify effects of nonlinear corrections to this theory that arise from band curvature and back-scattering.

9.
Phys Rev Lett ; 127(6): 063602, 2021 Aug 06.
Article in English | MEDLINE | ID: mdl-34420322

ABSTRACT

The interplay of interactions, symmetries, and gauge fields usually leads to intriguing quantum many-body phases. To explore the nature of emerging phases, we study a quantum Rabi triangle system as an elementary building block for synthesizing an artificial magnetic field. We develop an analytical approach to study the rich phase diagram and the associated quantum criticality. Of particular interest is the emergence of a chiral-coherent phase, which breaks both the Z_{2} and the chiral symmetry. In this chiral phase, photons flow unidirectionally and the chirality can be tuned by the artificial gauge field, exhibiting a signature of broken time-reversal symmetry. The finite-frequency scaling analysis further confirms the associated phase transition to be in the universality class of the Dicke model. This model can simulate a broad range of physical phenomena of light-matter coupling systems, and may have an application in future developments of various quantum information technologies.

10.
Phys Rev Lett ; 127(2): 023002, 2021 Jul 09.
Article in English | MEDLINE | ID: mdl-34296904

ABSTRACT

Dynamical fermionization refers to the phenomenon in Tonks-Girardeau gases where, upon release from harmonic confinement, the gases' momentum density profile evolves asymptotically to that of an ideal Fermi gas in the initial trap. This phenomenon has been demonstrated theoretically in hardcore and anyonic Tonks-Girardeau gases and was recently experimentally observed in a strongly interacting Bose gas. We extend this study to a one-dimensional spinor gas of arbitrary spin in the strongly interacting regime and analytically prove that the total momentum distribution after the harmonic trap is turned off approaches that of a spinless ideal Fermi gas, while the asymptotic momentum distribution of each spin component takes the same shape of the initial real space density profile of that spin component. Our work demonstrates the rich physics arising from the interplay between the spin and the charge degrees of freedom in a spinor system.

11.
Sensors (Basel) ; 21(12)2021 Jun 08.
Article in English | MEDLINE | ID: mdl-34201187

ABSTRACT

Digital video forensics plays a vital role in judicial forensics, media reports, e-commerce, finance, and public security. Although many methods have been developed, there is currently no efficient solution to real-life videos with illumination noises and jitter noises. To solve this issue, we propose a detection method that adapts to brightness and jitter for video inter-frame forgery. For videos with severe brightness changes, we relax the brightness constancy constraint and adopt intensity normalization to propose a new optical flow algorithm. For videos with large jitter noises, we introduce motion entropy to detect the jitter and extract the stable feature of texture changes fraction for double-checking. Experimental results show that, compared with previous algorithms, the proposed method is more accurate and robust for videos with significant brightness variance or videos with heavy jitter on public benchmark datasets.


Subject(s)
Algorithms , Lighting , Motion , Video Recording
12.
Phys Rev Lett ; 125(19): 190401, 2020 Nov 06.
Article in English | MEDLINE | ID: mdl-33216574

ABSTRACT

At low temperature, collective excitations of one-dimensional (1D) interacting fermions exhibit spin-charge separation, a unique feature predicted by the Tomonaga-Luttinger liquid (TLL) theory, but a rigorous understanding remains challenging. Using the thermodynamic Bethe ansatz (TBA) formalism, we analytically derive universal properties of a 1D repulsive spin-1/2 Fermi gas with arbitrary interaction strength. We show how spin-charge separation emerges from the exact TBA formalism, and how it is disrupted by the interplay between the two degrees of freedom that brings us beyond the TLL paradigm. Based on the exact low-lying excitation spectra, we further evaluate the spin and charge dynamical structure factors (DSFs). The peaks of the DSFs exhibit distinguishable propagating velocities of spin and charge as functions of interaction strength, which can be observed by Bragg spectroscopy with ultracold atoms.

13.
Phys Rev Lett ; 125(19): 195303, 2020 Nov 06.
Article in English | MEDLINE | ID: mdl-33216592

ABSTRACT

The (pseudo)spin degrees of freedom greatly enriches the physics of cold atoms. This is particularly so for systems with high spins (i.e., spin quantum number larger than 1/2). For example, one can construct not only the rank-1 spin vector, but also the rank-2 spin tensor in high spin systems. Here we propose a simple scheme to couple the spin tensor and the center-of-mass orbital angular momentum in a spin-1 cold atom system and show that this leads to a new quantum phase of the matter: the spin-nematic vortex state that features vorticity in an SU(2) spin-nematic tensor subspace. Under proper conditions, such states are characterized by quantized topological numbers. Our work opens up new avenues of research in topological quantum matter with high spins.

14.
Phys Rev Lett ; 122(19): 193201, 2019 May 17.
Article in English | MEDLINE | ID: mdl-31144953

ABSTRACT

We propose a generalized Dicke model that supports a quantum tricritical point. We map out the phase diagram and investigate the critical behavior of the model through an exact low-energy effective Hamiltonian in the thermodynamic limit. As predicted by the Landau theory of phase transition, the order parameter shows nonuniversality at the tricritical point. Nevertheless, as a result of the separation of the classical and the quantum degrees of freedom, we find a universal relation between the excitation gap and the entanglement entropy for the entire critical line including the tricritical point. Here the universality is carried by the emergent quantum modes, whereas the order parameter is determined classically.

15.
Phys Rev Lett ; 122(11): 110402, 2019 Mar 22.
Article in English | MEDLINE | ID: mdl-30951335

ABSTRACT

By inducing a Raman transition using a pair of Gaussian and Laguerre-Gaussian laser beams, we realize a ^{87}Rb condensate whose orbital angular momentum (OAM) and its internal spin states are coupled. By varying the detuning and the coupling strength of the Raman transition, we experimentally map out the ground-state phase diagram of the system for the first time. The transitions between different phases feature a discontinuous jump of the OAM and the spin polarization, and hence are of first order. We demonstrate the hysteresis loop associated with such first-order phase transitions. The role of interatomic interaction is also elucidated. Our work paves the way to explore exotic quantum phases in the spin-orbital-angular-momentum coupled quantum gases.

16.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-776118

ABSTRACT

OBJECTIVE@#To evaluate the curative efficacy of self-made fine-tuning setting in the process of femoral distal implantation of intramedullary nail.@*METHODS@#From October 2015 to October 2017, 66 cases of femoral shaft fracture were treated with anterograde interlocking intramedullary nail including 45 males and 21 females with a mean age of(37.21±11.18) years old. Among them, 36 cases were treated with the manufacture's aiming device and self-made fine-tuning setting (research group), other 30 cases were treated with the manufacture's aiming device(control group). The mean operation time, the times of C-arm scan in surgery, the post-operation complications and the fracture union were observed and compared in two groups.@*RESULTS@#Sixty-two cases acquired 8 to 15 months with a mean time of 12.4 months follow-up visit. The post-operation complications and the fracture union between the two groups had no significant difference(>0.05), the mean operation time and the times of C-arm scan in surgery had statistically significant difference(<0.05).@*CONCLUSIONS@#Self-made fine-tuning setting in the process of femoral interblocking intramedullary nail could shorten operation time and reduce the the times of C-arm scan.


Subject(s)
Adult , Female , Humans , Male , Middle Aged , Bone Nails , Femoral Fractures , Fracture Fixation, Intramedullary , Operative Time , Postoperative Period , Treatment Outcome
17.
Phys Rev Lett ; 120(13): 130402, 2018 Mar 30.
Article in English | MEDLINE | ID: mdl-29694171

ABSTRACT

We present a flexible scheme to realize exact flat Landau levels on curved spherical geometry in a system of spinful cold atoms. This is achieved by applying the Floquet engineering of a magnetic quadrupole field to create a synthetic monopole field in real space. The system can be exactly mapped to the electron-monopole system on a sphere, thus realizing Haldane's spherical geometry for fractional quantum Hall physics. This method works for either bosons or fermions. We investigate the ground-state vortex pattern for an s-wave interacting atomic condensate by mapping this system to the classical Thompson's problem. The distortion and stability of the vortex pattern are further studied in the presence of dipolar interaction. Our scheme is compatible with the current experimental setup, and may serve as a promising route of investigating quantum Hall physics and exotic spinor vortex matter on curved space.

18.
Phys Rev Lett ; 118(8): 083603, 2017 Feb 24.
Article in English | MEDLINE | ID: mdl-28282161

ABSTRACT

We propose a scheme to simulate topological physics within a single degenerate cavity, whose modes are mapped to lattice sites. A crucial ingredient of the scheme is to construct a sharp boundary so that the open boundary condition can be implemented for this effective lattice system. In doing so, the topological properties of the system can manifest themselves on the edge states, which can be probed from the spectrum of an output cavity field. We demonstrate this with two examples: a static Su-Schrieffer-Heeger chain and a periodically driven Floquet topological insulator. Our work opens up new avenues to explore exotic photonic topological phases inside a single optical cavity.

19.
World J Gastroenterol ; 22(25): 5822-30, 2016 Jul 07.
Article in English | MEDLINE | ID: mdl-27433095

ABSTRACT

AIM: To investigate clarithromycin resistance positions 2142, 2143 and 2144 of the 23SrRNA gene in Helicobacter pylori (H. pylori) by nested-allele specific primer-polymerase chain reaction (nested-ASP-PCR). METHODS: The gastric tissue and saliva samples from 99 patients with positive results of the rapid urease test (RUT) were collected. The nested-ASP-PCR method was carried out with the external primers and inner allele-specific primers corresponding to the reference strain and clinical strains. Thirty gastric tissue and saliva samples were tested to determine the sensitivity of nested-ASP-PCR and ASP-PCR methods. Then, clarithromycin resistance was detected for 99 clinical samples by using different methods, including nested-ASP-PCR, bacterial culture and disk diffusion. RESULTS: The nested-ASP-PCR method was successfully established to test the resistance mutation points 2142, 2143 and 2144 of the 23SrRNA gene of H. pylori. Among 30 samples of gastric tissue and saliva, the H. pylori detection rate of nested-ASP-PCR was 90% and 83.33%, while the detection rate of ASP-PCR was just 63% and 56.67%. Especially in the saliva samples, nested-ASP-PCR showed much higher sensitivity in H. pylori detection and resistance mutation rates than ASP-PCR. In the 99 RUT-positive gastric tissue and saliva samples, the H. pylori-positive detection rate by nested-ASP-PCR was 87 (87.88%) and 67 (67.68%), in which there were 30 wild-type and 57 mutated strains in gastric tissue and 22 wild-type and 45 mutated strains in saliva. Genotype analysis showed that three-points mixed mutations were quite common, but different resistant strains were present in gastric mucosa and saliva. Compared to the high sensitivity shown by nested-ASP-PCR, the positive detection of bacterial culture with gastric tissue samples was 50 cases, in which only 26 drug-resistant strains were found through analyzing minimum inhibitory zone of clarithromycin. CONCLUSION: The nested-ASP-PCR assay showed higher detection sensitivity than ASP-PCR and drug sensitivity testing, which could be performed to evaluate clarithromycin resistance of H. pylori.


Subject(s)
Drug Resistance, Bacterial/genetics , Helicobacter pylori/genetics , RNA, Ribosomal, 23S/genetics , Alleles , Anti-Bacterial Agents/pharmacology , Clarithromycin/pharmacology , DNA Primers , Gastric Mucosa/microbiology , Helicobacter Infections/microbiology , Helicobacter pylori/drug effects , Helicobacter pylori/physiology , Humans , Mutation , Polymerase Chain Reaction , Saliva/microbiology
20.
Oncotarget ; 7(27): 41186-41202, 2016 Jul 05.
Article in English | MEDLINE | ID: mdl-27172792

ABSTRACT

Epithelial-to-mesenchymal transition is a critical process that increases the malignant potential of melanoma by facilitating invasion and dissemination of tumor cells. This study identified genes involved in the regulation of cellular invasion and evaluated whether they can be targeted to inhibit melanoma invasion. We identified Peroxidasin (PXDN), Netrin 4 (NTN4) and GLIS Family Zinc Finger 3 (GLIS3) genes consistently elevated in invasive mesenchymal-like melanoma cells. These genes and proteins were highly expressed in metastatic melanoma tumors, and gene silencing led to reduced melanoma invasion in vitro. Furthermore, migration of PXDN, NTN4 or GLIS3 siRNA transfected melanoma cells was inhibited following transplantation into the embryonic chicken neural tube compared to control siRNA transfected melanoma cells. Our study suggests that PXDN, NTN4 and GLIS3 play a functional role in promoting melanoma cellular invasion, and therapeutic approaches directed toward inhibiting the action of these proteins may reduce the incidence or progression of metastasis in melanoma patients.


Subject(s)
Biomarkers, Tumor/genetics , Cell Movement/genetics , Epithelial-Mesenchymal Transition/genetics , Melanoma/genetics , Melanoma/pathology , Skin Neoplasms/genetics , Skin Neoplasms/pathology , Animals , Cell Line, Tumor , Chick Embryo , Gene Expression Regulation, Neoplastic/drug effects , Genetic Association Studies , Humans , Molecular Targeted Therapy , Neoplasm Invasiveness , Neoplasm Metastasis , RNA, Small Interfering/pharmacology , Transcriptome/drug effects
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