Photoelectron momentum distributions of triatomic CO_(2)molecules by circularly polarized attosecond pulses

Molecular-frame photoelectron momentum distributions(MF-PMDs)have been studied for imaging molecular structures.We investigate the MF-PMDs of CO_(2)molecules exposed to circularly polarized(CP)attosecond laser pulses bysolving the time-dependent Schrodinger equations based on the single-active-electron approximation frames.Results showthat high-frequency photons lead to photoelectron diffraction patterns,indicating molecular orbitals.These diffractionpatterns can be illustrated by the ultrafast photoionization models.However,for the driving pulses with 30 nm,a deviationbetween MF-PMDs and theoretically predicted results of the ultrafast photoionization models is produced because theCoulomb effect strongly influences the molecular photoionization.Meanwhile,the MF-PMDs rotate in the same directionas the helicity of driving laser pulses.Our results also demonstrate that the MF-PMDs in a CP laser pulse are the superpositionof those in the parallel and perpendicular linearly polarized cases.The simulations efficiently visualize molecularorbital geometries and structures by ultrafast photoelectron imaging.Furthermore,we determine the contribution of HOMOand HOMO-1 orbitals to ionization by varying the relative phase and the ratio of these two orbitals.

Laser-assisted XUV double ionization of helium atoms:Intensity dependence of joint angular distributions

We investigate the intensity effect of ultrashort assisting infrared laser pulse on the single-XUV-photon double ionization of helium atoms by solving full six-dimensional time-dependent Schrodinger equation with implement of finite element discrete variable representation.The studies of joint energy distributions and joint angular distributions of the two photoelectrons reveal the competition for ionized probabilities between the photoelectrons with odd parity and photoelectrons with even parity in single-XUV-photon double ionization process in the presence of weak infrared laser field,and such a competition can be modulated by changing the intensity of the weak assisting-IR laser pulses.The emission angles of the two photoelectrons can be adjusted by changing the laser parameters as well.We depict how the assisting-IR laser field enhances and/or enables the back-to-back and side-by-side emission of photoelectrons created in double ionization process.

Stent-assisted coiling of intracranial carotid ophthalmic segment aneurysm segment aneurysms:Long-term follow-up from a single center

Background:To evaluate the efficacy of stent-assisted coiling(SAC)for the treatment of carotid ophthalmic segment aneurysm segment aneurysms(OSAs)of the internal carotid artery(ICA)through detailed long-term follow-up of a large patient cohort.Methods:We retrospectively analyzed 88 consecutive patients with OSAs between January 2009 and January 2020 at our center.Angiographic results were evaluated using the modified Raymond grading system and clinical outcomes were evaluated using the mRS scale.The primary endpoints were major aneurysm recurrence and poor clinical outcomes for at least 18 months of follow-up.The patients were asked to attend clinical follow-up assessments and possibly undergo DSA or MR via telephone.Results:We enrolled 88 patients with 99 OSAs treated with coiling,of whom 76 were treated with SAC.The coiling procedures were successful in all 88 patients.Overall,complications occurred in 8 patients(9.1%).No procedure-related mortality was observed.67(76.1%)experienced immediate aneurysm occlusion at the end of the procedure.Long-term angiographic follow-up(18 months)was available in 45/88 aneurysms(51%)(average 18.7±5.2 months).Four patients continued their follow-up for 5 years after initial aneurysm treatment.After a clinical follow-up time of 28.7 months(range,12-51 months),85 patients(95.5%)achieved favorable clinical outcomes(mRS scores of 0-2).Conclusions:This study indicates that SAC treatment is a safe and effective therapeutic alternative for ruptured and unruptured OSAs.The procedural risks are low with relatively long-term effectiveness.

Serum Concentrations of Angiotensin, C-Reactive Protein, Interleukin-8, and Tumor Necrosis Factor-α in Train Driver Population

Train drivers are engaged in high-stress job. It may induce sleep, fatigue, and alertness loss at work, and endanger public safety. It’s unclear that cytokines of train driver would be influenced by their job. The research considers the hypothesis that stressful professions, such as train driver, influence the body’s immune system through the long-time and high-pressure working, and change production of neuro-immune factors. Using enzyme linked immunosorbent assay (ELISA), several neuro-immune factors were assayed among train drivers (N = 82) and health blood donors (N = 80) enrolled in the Yunnan Collaborative Innovation Center for Public Health and Disease Control. The concentrations of angiotensin, C-reactive protein (CRP), interleukin-8 (IL-8), and tumor necrosis factor-alpha (TNF-α) were determined. Kruskal-Wallis test and Dunn’s multiple comparisons test were performed for overall comparison between groups and for pairwise comparison, respectively. Statistical significance level was set at P < 0.05. The profession of train driving was not associated with significant increases or decreases in the systemic levels of inflammatory (CRP, IL-8, and TNF-α), but it was associated with the high expression of angiotensin in vivo. These findings suggest that the job of train driving may not be associated with significant alterations in systemic immune condition, but arouse the level of angiotensin.

Isoforskolin from Native Plant Coleus forskohlii of Yunnan, China Plays Multiple Biological Roles

Isoforskolin (ISOF) was isolated from Coleus forskohlii native to Yunnan in China. It is identified as one analog of diterpene forskolin (FSK) which comes from the Indian plant Coleus forskohlii. Researches found that the Yunnan native plant Coleus forskohlii contained rich ISOF but not FSK. ISOF was reported to activate adenylyl cyclase (AC) isoforms. The ophthalmologic and cardiovascular effects of ISOF were firstly reported in the 1990s. The researchers in Kunming, China, found ISOF could lower blood pressure and intraocular pressure. Recent researches found the respiratory tract effects of ISOF, and showed that ISOF significantly elevated cyclic adenosine monophosphate (cAMP) levels in rat lung homogenate, and relaxed the histamine-induced contraction of isolated guinea pig trachea and lung smooth muscle, isoforskolin pretreatment attenuates acute lung injury induced by lipopolysaccharide (LPS) in several models, lowered LPS-induced secretion of the inflammatory cytokine in human monocytes.

Interference effect of photoionization of hydrogen atoms by ultra-short and ultra-fast high-frequency chirped pulses

The photoionization of a hydrogen atom from its ground state with ultra-fast chirped pulses is investigated by numerically solving the time-dependent Schrodinger equation within length,velocity,and Kramers-Henneberger gauges.Converged results for all gauges for chirp-free pulses agree with the prediction of dynamic interference for ground state hydrogen atoms predicted recently by Jiang and Burgdorfer[Opt.Express 26,19921(2018)].In addition,we investigated photoelectron spectra of hydrogen atoms by chirped laser pulses,and showed that dynamic interference effect will be weaken for pulses with increasing linear chirp.Our numerical results can be understood and discussed in terms of an interplay of photoelectron wavepackets from first and second halves of laser enevelop,including the ac Stark energy level shift of the photoelectron final state and atomic stabilization effect at ultra-high intensities.

Hemodynamic analysis of intracranial aneurysms using phase-contrast magnetic resonance imaging and computational fluid dynamics

Additional hemodynamic parameters are highly desirable in the clinical management of intracranial aneurysm rupture as static medical images cannot demonstrate the blood flow within aneurysms. There are two ways of obtaining the hemodynamic information-by phase-contrast magnetic resonance imaging (PCMRI) and computational fluid dynamics (CFD). In this paper, we compared PCMRI and CFD in the analysis of a stable patient's specific aneurysm. The results showed that PCMRI and CFD are in good agreement with each other. An additional CFD study of two stable and two ruptured aneurysms revealed that ruptured aneurysms have a higher statistical average blood velocity, wall shear stress, and oscillatory shear index (OSI) within the aneurysm sac compared to those of stable aneurysms. Furthermore, for ruptured aneurysms, the OSI divides the positive and negative wall shear stress divergence at the aneurysm sac.

Chirp-dependent ionization of hydrogen atoms in the presence of super-intense laser pulses

We perform a theoretical study on dynamic interference in single photon ionization of ground state hydrogen atoms in the presence of a super-intense ultra-fast chirped laser pulse of different chirp types(equal-power and equal-FWHM laser pulses)by numerically solving the time-dependent Schrödinger equation in one dimension.We investigate the influences of peak intensity and chirp parameters on the instantaneous ionization rate and photoelectron yield,respectively.We also compare the photoelectron energy spectra for the ionization by the laser pulses with different chirp types.We find that the difference between the instantaneous ionization rates for the ionization of hydrogen atom driven by two different chirped laser pulses is originated from the difference in variation of vector potentials with time.

Relativistic electron scattering from freely movable proton/μ^+ in the presence of strong laser field

We have investigated the electron scattering from the freely movable spin-1/2 particle in the presence of a linearly polarized laser field in the first Born approximation.The laser-dressed state of electrons is described by a time-dependent wave function which is derived from a perturbation treatment.With the aids of numerical simulations, we explore the dependencies of the differential cross section on the laser field intensity as well as the electron-impact energy.Due to the mobility of the target, the differential cross section of this process is smaller than that of Mott scattering.

Atomic even-harmonic generation due to symmetry-breaking effects induced by spatially inhomogeneous field

We ab initio investigate the interaction between the hydrogen atom and the inhomogeneous field which is induced by resonant plasmons within a metal nanostructure.Same as normal laser pulse(homogeneous field), only odd-harmonic generation occurs when the bow-tie nanostructure is utilized.For the single nanotip case, the even-harmonic generation can be distinctly found in the harmonic emission spectrum.By investigating the symmetry and trajectories of different inhomogeneous fields, we demonstrate that the breaking symmetry of system can enable even high harmonic generations.

Manipulating Nonsequential Double Ionization of Argon Atoms via Orthogonal Two-Color Field

Using a three-dimensional classical ensemble model,we investigate the dependence of relative frequency and relative initial phase for nonsequential double ionization(NSDI)of atoms driven by orthogonal two-color(OTC)fields.Our findings reveal that the NSDI probability is clearly dependent on the relative initial phase of OTC fields at different relative frequencies.The inversion analysis results indicate that adjusting the relative frequency of OTC fields helps control returning probability and flight time of the first electron.Furthermore,manipulating the relative frequency at the same relative initial phases can vary the revisit time of the recolliding electron,leading that the emission direction of Ar^(2+)ions is explicitly dependent on the relative frequency.

Relation between Cardiac Injury and Elevated Levels of Inflammatory Biomarkers in Patients with Severe COVID-19

Background:Since early December 2019,coronavirus disease 2019(COVID-19)has emerged as a global pandemic and public health crisis.This study aims to explore the relationship between cardiac injury and infl ammatory biomarkers in patients with severe COVID-19.Methods:We collected data on 91 patients with a confi rmed diagnosis of severe COVID-19 from February 8 to March 31,2020.Demographic characteristics,clinical data,and in-hospital outcomes were compared.The relationship between cardiac injury and infl ammatory biomarkers was analyzed.Logistic regression was used to explore the independent risk factors for cardiac injury.Results:The mean age of all patients was 61 years±14 years.About half of the patients were male.Hypertension and coronary heart disease were more common in the cardiac injury group.The levels of infl ammatory biomarkers in patients who experienced cardiac injury were generally higher than the levels of those without cardiac injury,including interleukin-6,interleukin-2 receptor(IL-2R),procalcitonin,and high-sensitivity C-reactive protein.There were positive correlations between the levels of high-sensitivity troponin I and N-terminal prohormone of brain natriuretic peptide and the levels of infl ammatory biomarkers.Logistic regression shows that IL-2R(odds ratio 1.001,95%confi dence interval 1.000–1.002,P=0.045)and comorbidities(odds ratio 4.909,95%confi dence interval 1.231–19.579,P=0.024)are independent risk factors for cardiac injury in patients with severe COVID-19.Conclusion:High levels of infl ammatory biomarkers are associated with higher risk of cardiac injury in patients with severe COVID-19.IL-2R and comorbidities are predictors of cardiac injury.

Rapid determination of hyaluronic acid concentration in fermentation broth with near-infrared spectroscopy

Hyaluronic acid(HA)concentration is an important parameter in fermentation process.Cur-rently,carbazole assay is widely used for HA content determination in routine analysis.However,this method is time-consuming,environment polluting and has the risk of microbial contarmi-nation,as well as the results lag behind fermentation process.This paper attempted the feasibility to predict the concentration of HA in fermentation broth by using near infrared(NIR)spec-troscopy in transmission mode.In this work,a total of 56 samples of fermentation broth from 7 batches were analyzed,which contained HA in the range of 2.35-9.69 g/L.Diferent data pre-processing methods were applied to construct calibration models.The final optimal model was obtained with first derivative using Savitzky-Golay smoothing(9 points window,second-order polynomial)and partial least squares(PLS)regression with leave-one-block out CrOsS validation.The correlation cofficient and Root Mean Square Error of prediction set is 0.98 and 0.43 g/L,respetively,which show the possibility of NIR as a rapid method for microanalysis and to be a promising tool for a rapid assay in HA fermentation.

<i>De novo</i>cavernous aneurysms development after contralateral parent artery occlusion—Two cases report

A 53-year-old woman developed a de novo aneurysm after contralateral internal carotid artery occlusion, and another 42-year-old woman developed a de novo aneurysm after contralateral vertebral artery occlusion. Both patients experienced a rapid development of de novo aneurysm formation, 6 and 9 months, respectively. The development of de novo aneurysm on the contralateral artery after parent artery occlusion showed that female and medium age may be contributory factors. In addition, the hemodynamic changes may be associated with the development of de novo aneurysm after contralateral parent artery occlusion.

Tunable spectral shift of high-order harmonic generation in atoms using a sinusoidally phase-modulated pulse

High-order harmonic generation(HHG)from an atom illuminated by a sinusoidally phase-modulated pulse is investigated by solving the time-dependent Schrödinger equation.The spectral shift that occurs in atomic HHG can be achieved easily using our laser pulse.It is shown that the photon energy of the generated harmonics is controllable within the range of 1 eV.The shift of the frequency peak position is rooted in the asymmetry of the rising and falling parts of the laser pulse.We also show that by varying the phase parameters in the frequency domain of the laser one can adjust and control the shift in atomic harmonic spectra.

Multiphoton Ionization of Potassium Atoms in Femtosecond Laser Fields

We study the multiphoton ionization of potassium atoms in 800 nm and 400 nm femtosecond laser fields.In the 800 nm laser field,the potassium atom absorbs three photons and emits one electron via one photon resonance with the 4p intermediate state with the help of the ac-Stark shift.The resonance feature is clearly shown as an Autler-Townes(AT) splitting and is mapped out in the electron kinetic energy spectrum.In a 400 nm laser field,although one photon resonance is possible with the 5p state,no splitting is observed.The different transition amplitudes between 4s-4p and 4s-5p explain the observed results.Due to the AT effect,an unexpected peak in the photoelectron energy spectrum that violates the dipole transition rule is observed.A preliminary explanation involving the spin-orbit interaction in the p state is given to account for this component.The observed ATsplitting in the electron kinetic energy distribution can be used as an effective method to calibrate the intensity of a laser field.

Resolution of Symptoms after Parent Artery Occlusion Treatment for Giant Cavernous Carotid Artery Aneurysms

Background and Objective: Giant cavernous carotid artery aneurysms (CCAAs) often produce a variety of neurological deficits, primarily those related to ophthalmoplegia/paresis and headache. This study was designed to evaluate the resolution of symptoms after parent artery occlusion (PAO) treatment for giant CCAAs. Methods: We retrospectively reviewed a series of 17 consecutive giant CCAAs treated with PAO treatment. All patients were evaluated by balloon occlusion test (BOT) before treatment. Patients who could tolerate BOT were treated by PAO. The following outcomes were analyzed: angiographic assessment, evolution of symptoms and outcome at clinical follow-up using modified Rankin Scale (mRS). Results: A total number of 17 giant CCAAs were treated by PAO. The initial post-procedure and follow-up angiogram revealed complete occlusion in all patients, no new lesion was detected. Periprocedural infarcts occurred in 1 patient (5.9%). Procedure-related mortality and morbidity were 0% and 5.9%, respectively. At mean 31.8 months clinical follow-up, symptoms had disappeared in 7 (41.2%) of the patients, partially improved in 5 (29.4%), remained unchanged in 4 (23.5%) and worsened in 1 (5.9%) of cases. Sixteen (94.1%) patients presented a good clinical outcome (mRS 0 - 1). Conclusion: Most patients in our series improved or remained stable after PAO. The results of this study indicate that PAO can improve the outcome of those symptomatic giant CCAAs if BOT can be tolerated.

Electron vortex generations in photoionization of hydrogen atoms by circularly-polarized chirped attosecond pulses

By numerically solving the time-dependent Schr?dinger equation and employing the analytical perturbative model,we investigated the chirp-induced electron vortex in the photoionization of hydrogen atoms by a pair of counter-rotating circularly polarized chirped attosecond extremely ultraviolet pulses.We demonstrated that single-photon ionization of hydrogen atoms generates photoelectron momentum distributions(PMDs)with distinct helical vortex structures either with or without a time delay between two counter-rotating circularly polarized laser pulses.These structures are highly sensitive to both the time delay between the pulses and their chirp parameters.Our analytical model reveals that the splitting of vortex spirals is caused by the sign changing of the chirp-induced frequency-dependent time delay.We showed that to obtain the counterpart of the PMD under a pair of counter-rotating circularly polarized chirped pulses,both chirp parameters and ordering of pulses need to be reversed.

p-wave resonances in the exponential cosine screened Coulomb potential

We perform benchmark calculations of the p-wave resonances in the exponentially cosine screened Coulomb potential using the uniform complex-scaling generalized pseudo-spectral method.The present results show significant improvement in calculation accuracy compared to previous predictions and correct the misidentification of resonance electron configuration in previous works.It is found that the resonance states approximately follow an n^(2)-scaling law which is similar to the bound counterparts.The birth of a new resonance would distort the trajectory of an adjacent higher-lying resonance.

Efficacy and Safety of Antibiotics for the Treatment of Relapsing Fever:A Systematic Review and Network Meta-analysis

Relapsing fever is an acute infectious disease caused by a variety of relapsing fever-associated spirochetes,for which no optimal treatment has been developed.The purposes of this study were to compare the efficacy and safety of commonly used antibiotics for the treatment of relapsing fever using a network meta-analysis approach and to explore the advantages of each drug based on the current evidence.This study examined nine published studies involving 1416 patients with relapsing fever treated with penicillin,erythromycin,tetracycline,doxycycline,minocycline or chloramphenicol.The odds ratio(OR)and 95% confidence interval(CI)were used as influence indices for discontinuous data,and the efficacy and safety of drugs were ranked by the surface under the cumulative ranking(SUCRA)curve.The primary outcomes of this study were mortality and cure rates,and the secondary outcomes were the rates of Jarisch-Herxheimer reaction and relapse.Erythromycin(SUCRA,84.5%)was the most effective antibiotic for reducing mortality,whereas tetracycline was the most effective antibiotic for improving the cure rate(SUCRA,69.3%)and reducing the relapse rate(SUCRA,79.7%),and minocycline(SUCRA,66.4%)was the most effective antibiotic for reducing Jarisch-Herxheimer reactions.In addition,our network meta-analysis showed that tetracycline is superior to penicillin for improving the cure rate(OR,5.91;95%CI,2.21-15.81)and reducing the relapse rate(OR,0.16;95%CI,0.04-0.67).