Eikenella corrodens isolated from pleural effusion:A case report

BACKGROUND The bacterium Eikenella,classified as a gram-negative member of the phylum Proteobacteria,is distinguished by its rarity,corrosive nature,facultative anaerobic properties,and conditional pathogenicity.It represents the sole species within its genus-Eikenella corrodens(E.corrodens)-and can be found colonizing both human and animal oral and nasopharyngeal regions.Additionally,it occasionally inhabits the gastrointestinal or urogenital tracts.However,its slow growth rate can be attributed to its high nutritional requirements.However,there is an uneven distribution of construction and diagnostic capacity in China which poses undeniable challenges for the clinical examination and analysis of this case,especially in the basic hospitals.CASE SUMMARY Here we presented a case of empyema associated with E.corrodens infection in a 67-year-old male patient without any previous history of infectious diseases in our primary hospital in Dongguan district of China.The patient was admitted due to recurrent worsening cough,sputum production,and dyspnea for 3 d,which had persisted for over 20 years.Moreover,the patient experienced a onehour episode of unconsciousness.Upon admission,immediate comprehensive examinations were conducted on the patient which subsequently led to his admission to the intensive care unit.Meanwhile,the patient presented with drowsiness and profuse sweating along with bilateral conjunctival edema observed during initiation of non-invasive ventilation,suggesting empyema.A significant amount of coffee-colored malodorous pleural fluid was drained during the procedure above and sent to the laboratory department for inspection.Finally,laboratory culture results confirmed the presence of E.corrodens infection in the pleural fluid sample.The patient received antimicrobial therapy until died on day 22 in the hospital.CONCLUSION In this report,we presented a case of empyema associated with E.corrodens infection.Multiple courses of morphological examination,viable culture analysis,and biochemical identification revealed its difficulties in detecting distinctive characteristics,as well as a detection model worth promoting.It’s just that there were still certain deficiencies in terms of morphological assessment,biochemical identification,and drug susceptibility testing.

Yinhuang granule alleviates carbon tetrachloride-induced liver fibrosis in mice and its mechanism

BACKGROUND Liver fibrosis is a formidable global medical challenge,with no effective clinical treatment currently available.Yinhuang granule(YHG)is a proprietary Chinese medicine comprising Scutellariae Radix and Lonicerae Japonicae Flos.It is frequently used for upper respiratory tract infections,pharyngitis,as well as acute and chronic tonsillitis.AIM To investigate the potential of YHG in alleviating carbon tetrachloride(CCl4)-induced liver fibrosis in mice.METHODS To induce a hepatic fibrosis model in mice,this study involved intraperitoneal injections of 2 mL/kg of CCl4 twice a week for 4 wk.Meanwhile,liver fibrosis mice in the low dose of YHG(0.4 g/kg)and high dose of YHG(0.8 g/kg)groups were orally administered YHG once a day for 4 wk.Serum alanine/aspartate aminotransferase(ALT/AST)activity and liver hydroxyproline content were detected.Sirius red and Masson's trichrome staining assay were conducted.Realtime polymerase chain reaction,western-blot and enzyme-linked immunosorbent assay were conducted.Liver glutathione content,superoxide dismutase activity level,reactive oxygen species and protein carbonylation amount were detected.RESULTS The administration of YHG ameliorated hepatocellular injury in CCl4-treated mice,as reflected by decreased serum ALT/AST activity and improved liver histological evaluation.YHG also attenuated liver fibrosis,evident through reduced liver hydroxyproline content,improvements in Sirius red and Masson's trichrome staining,and lowered serum hyaluronic acid levels.Furthermore,YHG hindered the activation of hepatic stellate cells(HSCs)and ameliorated oxidative stress injury and inflammation in liver from CCl4-treated mice.YHG prompted the nuclear accumulation of nuclear factor erythroid 2-related factor 2(Nrf2)and upregulated the expression of Nrf2-dependent downstream antioxidant genes.In addition,YHG promoted mitochondrial biogenesis in liver from CCl4-treated mice,as demonstrated by increased liver adenosine triphosphate content,mitochondrial DNA levels,and the expression of peroxisome proliferator-activated receptor gamma coactivator 1 alpha and nuclear respiratory factor 1.CONCLUSION YHG effectively attenuates CCl4-induced liver fibrosis in mice by inhibiting the activation of HSCs,reducing inflammation,alleviating liver oxidative stress damage through Nrf2 activation,and promoting liver mitochondrial biogenesis.

Progress on traditional Chinese medicine in improving hepatic fibrosis through inhibiting oxidative stress

Hepatic fibrosis is a common pathological process that occurs in the development of various chronic liver diseases into cirrhosis and liver cancer,characterized by excessive deposition of the extracellular matrix.In the past,hepatic fibrosis was thought to be a static and irreversible pathological process.In recent years,with the rapid development of molecular biology and the continuous in-depth study of the liver at the microscopic level,more and more evidence has shown that hepatic fibrosis is a dynamic and reversible process.Therefore,it is particularly important to find an effective,simple,and inexpensive method for its prevention and treatment.Traditional Chinese medicine(TCM)occupies an important position in the treatment of hepatic fibrosis due to its advantages of low adverse reactions,low cost,and multi-target effectiveness.A large number of research results have shown that TCM monomers,single herbal extracts,and TCM formulas play important roles in the prevention and treatment of hepatic fibrosis.Oxidative stress(OS)is one of the key factors in the occurrence and development of hepatic fibrosis.Therefore,this article reviews the progress in the understanding of the mechanisms of TCM monomers,single herbal extracts,and TCM formulas in preventing and treating hepatic fibrosis by inhibiting OS in recent years,in order to provide a reference and basis for drug therapy of hepatic fibrosis.

Tuning composite solid-state electrolyte interface to improve the electrochemical performance of lithium-oxygen battery

Thin and flexible composite solid-state electrolyte(SSE) is considered to be a prospective candidate for lithium-oxygen(Li-O_(2)) batteries with the aim to address the problems of unsatisfied safety, terrible durability as well as inferior electrochemical performance. Herein, in order to improve the safety and durability, a succinonitrile(SN) modified composite SSE is proposed. In this SSE, SN is introduced for eliminating the boundary between ceramic particles, increasing the amorphous region of polymer and ensuring fast ionic transport. Subsequently, the symmetric battery based on the proposed SSE achieves a long cycle life of 3000 h. Moreover, the elaborate cathode interface through the SN participation effectively reduces the barriers to the combination between lithium ions and electrons, facilitating the corresponding electrochemical reactions.As a result, the solid-state Li-O_(2)battery based on this SSE and tuned cathode interface achieves improved electrochemical performance including large specific capacity over 12,000 m Ah g^(-1), enhanced rate capacity as well as stable cycle life of 54 cycles at room temperature. This ingenious design provides a new orientation for the evolution of solid-state Li-O_(2)batteries.

Electric and thermal transport properties of topological insulator candidate LiMgBi

We report the transport properties of a topological insulator candidate,LiMgBi.The electric resistivity of the title compound exhibits a metal-to-semiconductor-like transition at around 160 K and tends to saturation below 50 K.At low temperatures,the magnetoresistance is up to~260%at 9 T and a clear weak antilocalization effect is observed in the low magnetic-field region.The Hall measurement reveals that LiMgBi is a multiband system,where hole-type carriers(nh~1018 cm^(-3))play a major role in the transport process.Remarkably,LiMgBi possess a large Seebeck coefficient(~440μV/K)and a moderate thermal conductivity at room temperature,which indicate that LiMgBi is a promising candidate in thermoelectric applications.

中国长株潭城市群绿色基础设施对步行体力活动的影响机制研究

步行体力活动可以改善居民健康,探索绿色基础设施对步行体力活动的影响机制是建设健康城市环境的重要一环。本文以中国长株潭城市群绿色基础设施与居民步行体力活动的频率和强度为研究对象,通过识别城市群绿色基础设施的构成要素,分析步行体力活动的空间分布特征;进而构建城市群绿色基础设施指标体系,运用多元线性回归模型分析城市群绿色基础设施对居民步行体力活动频率和强度的影响机制。研究发现,长株潭城市群居民的步行体力活动轨迹主要分布在绿色基础设施的连接廊道和小型场地中。绿色基础设施的内部环境、外部环境与空间格局均对居民步行体力活动的影响存在差异。其中,外部环境指标中的居住密度、房价水平,内部环境指标中的公共厕所密度、城市广场密度、公交站点密度、绿地面积占比,以及空间格局指标中的最大斑块面积和斑块聚合度指数均与步行体力活动的频率和强度有显著相关性;外部环境指标中的土地利用混合度、日平均气温和内部环境指标中的水体面积占比仅与步行体力活动的强度有显著相关性,内部环境指标中的步道密度仅与步行体力活动的频率有显著相关性。最后,本文分别从外部环境、内部环境和空间格局三个方面提出城市群绿色基础设施的建设及更新策略,以期改善居民步行体力活动环境,充分发挥城市群绿色基础设施的生态和社会价值。

Ultrasensitive polarization-dependent terahertz modulation in hybrid perovskites plasmoninduced transparency devices

Active control of metamaterial properties with high tunability of both resonant intensity and frequency is essential for advanced terahertz(THz) applications, ranging from spectroscopy and sensing to communications.Among varied metamaterials, plasmon-induced transparency(PIT) has enabled active control with giant sensitivity by embedding semiconducting materials. However, there is still a stringent challenge to achieve dynamic responses in both intensity and frequency modulation. Here, an anisotropic THz active metamaterial device with an ultrasensitive modulation feature is proposed and experimentally studied. A radiative-radiative-coupled PIT system is established, with a frequency shift of 0.26 THz in its sharp transparent windows by polarization rotation. Enabled by high charge-carrier mobility and longer diffusion lengths, we utilize a straightforwardly spincoated MAPbI3 film acting as a photoactive medium to endow the device with high sensitivity and ultrafast speed.When the device is pumped by an ultralow laser fluence, the PIT transmission windows at 0.86 and 1.12 THz demonstrate a significant reduction for two polarizations, respectively, with a full recovery time of 561 ps. In addition, we numerically prove the validity that the investigated resonator structure is sensitive to the optically induced conductivity. The hybrid system not only achieves resonant intensity and frequency modulations simultaneously, but also preserves the all-optical-induced switching merits with high sensitivity and speed, which enriches multifunctional subwavelength metamaterial devices at THz frequencies.

Ultrafast fiber lasers mode-locked by two-dimensional materials:review and prospect

The year 2019 marks the 10th anniversary of the first report of ultrafast fiber laser mode-locked by graphene.This result has had an important impact on ultrafast laser optics and continues to offer new horizons.Herein,we mainly review the linear and nonlinear photonic properties of two-dimensional(2D)materials,as well as their nonlinear applications in efficient passive mode-locking devices and ultrafast fiber lasers.Initial works and significant progress in this field,as well as new insights and challenges of 2D materials for ultrafast fiber lasers,are reviewed and analyzed.

Polarization-tunable nonlinear absorption patterns from saturated absorption to reverse saturated absorption in anisotropic GeS flake and an application of all-optical switching

Due to the unique anisotropic chemical and physical properties,two-dimensional(2D)layered materials such as IV-VI monochalcogenides with puckered honeycomb structure,have received considerable interest recently.Among the IV-VI layered MX(M=Ge,Sn;X=Se,S)compounds,germanium sulfide(Ge S)stands out for its strongest anisotropic thermal conductivities and figure-of-merit values.Additionally,the layer-independent direct energy bands(Eg^1.6 e V,E1~2.1 e V)of Ge S flake provide excellent insights into further applications as visible photodetectors.Herein,the polarization-tunable nonlinear absorption(NA)patterns of Ge S flake have been systematically investigated.Specifically both the polarization-dependent Raman spectroscopy and the linear absorption(LA)spectroscopy were employed to characterize the lattice orientation and absorption edges of the251-nm Ge S flake.Considering the low damage threshold of Ge S flake,the Ge S/graphene heterostructure was fabricated to increase the threshold without changing the nonlinear properties of Ge S.Our NA results demonstrated that a 600-nm femtosecond laser with different polarizations would excite the saturated-absorption(SA)effect along armchair and reversesaturated-absorption(RSA)effect along zigzag in the Ge S/graphene heterostructure.Moreover,the function of the polarization-based Ge S/graphene heterostructure all-optical switch was experimentally verified.Notably,thanks to the polarization-dependent NA patterns(SA/RSA)of Ge S,the"ON"and"OFF"states of the all-optical switch can be accomplished by high and low transmittance states of continuous-wave laser(532 nm,80 n W),whose state can be controlled by the polarization of femtosecond switching laser(600 nm,35 fs,500 Hz,12 GW cm-2).The ON/OFF ratio can achieve up to 17%by changing polarization,compared with the ratios of 3.0%by increasing the incident power of switching light in our experiment.The polarization-tunable absorption patterns introduced in this work open up real perspectives for the next-generation optoelectronic devices based on Ge S/graphene heterostructure.

Saturated absorption of different layered Bi_2Se_3 films in the resonance zone

Here, we used the micro P-scan method to investigate the saturated absorption(SA) of different layered Bi_2Se_3 continuous films. Through resonance excitation, first, we studied the influence of the second surface state(SS) on SA. The second SS resonance excitation(～2.07 e V) resulted in a free carrier cross section that was 4 orders of magnitude larger than usual. At the same time, we found that the fast relaxation process of the massless Dirac electrons is much shorter than that of electrons in bulk states. Moreover, the second SS excitation resonance reduced the saturation intensity. Second, we studied the effect of the thickness on the SA properties of materials.The results showed that the saturation intensity was positively correlated to the thickness, the same as the modulation depth, and the thicker the Bi_2Se_3 film was, the less the second SS would influence it. This work demonstrated that by using Bi_2Se_3 as a saturable absorber through changing the thickness or excitation wavelength, a controllable SA could be achieved.

A convenient method to prepare random LA/CL copolymers from poly(L-lactide) and ε-caprolactone

Sequential addition of L-lactide(LA) followed by ε-caprolactone(CL), and simultaneous addition of both monomers, afforded random LA/CL copolymers in the presence of lanthanide aryloxides under mild conditions. Transesterification was proved to play a predominant role in random copolymer formation. Moreover, treatment of poly(L-lactide) with ε-CL led to random copolymer formation, which provides a new strategy not only to prepare random LA/CL copolymers, but also to directly modify PLLA.

Spherical contact mechanical analysis of roller cone drill bits journal bearing

Fang contact model is introduced to analyze stress of the spherical fixed ring journal bearing.Developed calculation programs in the MATLAB software which are utilized to calculate the contact characteristics of roller cone drill bits spherical fixed ring journal bearing.In addition,effects of external load,radius clearance values,and material parameter on the mechanics performance were investigated.The results show that the value of external load has a direct pronounced effect on the contact characteristics of journal bearing.There is a significant positive correlation between contact pressure and external load,radius clearance value,and the Young's modulus of material.However,there is an evident negative correlation between contact radius of journal bearing and radius clearance value,and the Young's modulus of material.The smaller radius clearance value of journal bearing is,the more centralized contact region will be,so the corresponding contact pressure will be higher.From the perspective of reducing friction and wear,we need select the materials which have high strength and good toughness.Not only might this can improve the wear resistance,it also effectively decreases the contact pressure.In this case,we can prolong the service life of roller cone drill bits journal bearing.

Soliton mode-locked fiber laser with high-quality MBE-grown Bi2Se3 film

In this work, a soliton mode-locked erbium-doped fiber laser(EDFL) with a high-quality molecular beam epitaxy(MBE)-grown topological insulator(TI) Bi2Se3 saturable absorber(SA) is reported.To fabricate the SA device, a 16-layer Bi2Se3 film was grown successfully on a 100 μm thick SiO2 substrate and sandwiched directly between two fiber ferrules.The TI-SA had a saturable absorption of 1.12% and a saturable influence of 160 MW/cm^2.After inserting the TI-SA into the unidirectional ring-cavity EDFL, self-starting mode-locked soliton pulse trains were obtained at a fundamental repetition rate of 19.352 MHz.The output central wavelength, pulse energy,pulse duration, and signal to noise ratio of the radio frequency spectrum were 1530 nm,18.5 p J, 1.08 ps, and 60d Bm, respectively.These results demonstrate that the MBE technique could provide a controllable and repeatable method for the fabrication of identical high-quality TI-SAs, which is critically important for ultra-fast pulse generation.

Temperature insensitive multi-channel light amplification systems on SOI platform

We present a theoretical analysis of a novel multi-channel light amplification photonic system on chip,where the nonlinear Raman amplification phenomenon in the silicon(Si)wire waveguide is considered.Particularly,a compact and temperature insensitive Mach–Zehnder interferometer filter working as demultiplexer is also exploited,allowing for the whole Si photonic system to be free from thermal interference.The propagation of the multi-channel pump and Stokes lights is described by a rigorous theoretical model that incorporates all relevant linear and nonlinear optical effects,including the intrinsic waveguide optical losses,first-and second-order frequency dispersion,self-phase and cross-phase modulation,phase shift and two-photon absorption,free-carriers dynamics,as well as the inter-pulse Raman interaction.Notably,to prevent excessive drift of the transmission window of the demultiplexer caused by ambient temperature variations and high thermo-optical coefficient of Si,an asymmetric waveguide width is adopted in the upper and lower arms of each Mach–Zehnder interferometer lattice cell.A Chebyshev half-band filter is utilized to achieve a flat pass-band transmission,achieving a temperature sensitivity of<1.4 pm=K and over 100 K temperature span.This all-Si amplifier shows a thermally robust behavior,which is desired by future Si-on-insulator(SOI)applications.