Numerical design of an efficient Ho^(3+)-doped InF3 fiber laser at~3.2μm

In this work,we theoretically unlock the potential of Ho^(3+)-doped InF3 fiber for efficient~3.2μm laser generation(from the ^(5)F_(4),^(5)S_(2)→^(5)F_(5) transition),by employing a novel dual-wavelength pumping scheme at 1150 nm and 980 nm,for the first time.Under clad-coupled 1150 nm pumping of 5 W,~3.2μm power of 3.6 W has been predicted with the optical-to-optical efficiency of 14.4%.Further efficient power scaling,however,is blocked by the output saturation with 980 nm pumping.To alleviate this behavior,the cascaded ^(5)I_(5)→^(5)I_(6) transition,targeting~3.9μm,has been activated simultaneously,therefore accelerating the population circulation between the laser upper level ^(5)F_(4),^(5)S_(2) and long-lived ^(5)I_(6) level under 980 nm pumping.As a result,enhanced~3.2μm power of 4.68 W has been obtained with optical-to-optical efficiency of 15.6%.Meanwhile the~3.9μm laser,yielding power of 2.76 W with optical-to-optical efficiency of 9.2%,is theoretically achievable as well with a moderate heat load,of which the performance is even better than the prior experimentally and theoretically reported Ho^(3+)-doped InF3 fiber lasers emitting at~3.9μm alone.This work demonstrates a versatile platform for laser generation at~3.2μm and~3.9μm,thus providing the new opportunities for many potential applications,e.g.,polymer processing,infrared countermeasures,and free-space communications.

Linearly Polarized Polarization-Maintaining Er^(3+)-Doped Fluoride Fiber Laser in the Mid-Infrared

We demonstrated the~2.8-μm and~3.5-μm linearly polarized continuous wave(CW)laser outputs from a polarization-maintaining(PM)Er^(3+)-doped fluoride fiber laser.By introducing a film polarizer into the cavity to select the laser polarization orientation,the~2.8-μm linearly polarized CW laser with a high polarization extinction ratio(PER)of~23 dB and maximum output power of 2.37 W was achieved under double-end pumping at 976 nm.By adding another 1981-nm pump source simultaneously,the~3.5-μm linearly polarized CW laser was also obtained,giving higher PER of~27 dB and maximum output power of 307 mW which is only limited by the available power of 1981-nm pump.To the best of our knowledge,this is the first report on a mid-infrared linearly polarized CW PM fiber laser in the>2.5-μm mid-infrared region.This work not only opens up opportunities for some new mid-infrared applications,but also provides a promising platform for developing high-stability and versatile mid-infrared laser sources.

Association of bone turnover biomarkers with severe intracranial and extracranial artery stenosis in type 2 diabetes mellitus patients

BACKGROUND Intracranial and extracranial artery stenosis is associated with cerebral infarction.Vascular calcification and atherosclerosis are the main causes of stenosis and major risk factors for cardiovascular and cerebrovascular events in patients with type 2 diabetes mellitus(T2DM).Bone turnover biomarkers(BTMs)are associated with vascular calcification,atherosclerosis,glucose,and lipid metabolism.AIM To investigate the association of circulating BTM levels with severe intracranial and extracranial artery stenosis in patients with T2DM.METHODS For this cross-sectional study including 257 T2DM patients,levels of the BTMs serum osteocalcin(OC),C-terminal cross-linked telopeptide of type I collagen(CTX),and procollagen type I N-peptide were measured by electrical chemiluminescent immunoassay,and artery stenosis was assessed by color Doppler and transcranial Doppler.Patients were grouped according to the existence and location(intracranial vs.extracranial)of artery stenosis.Correlations between BTM levels,previous stroke,stenosis location,and glucose and lipid metabolism were analyzed.RESULTS T2DM patients with severe artery stenosis had a higher frequency of previous stroke and levels of all three tested BTMs(all P<0.05)than patients without.Some differences in OC and CTX levels were observed according to the location of artery stenosis.Significant associations were also observed between BTM levels and some glucose and lipid homeostasis parameters.On multivariate logistic regression analysis,all BTMs were significant predictors of artery stenosis in T2DM patients with and without adjustment for confounding factors(all P<0.001),and receiver operating characteristic curve analysis demonstrated the ability of BTM levels to predict artery stenosis in T2DM patients.CONCLUSION BTM levels were found to be independent risk factors for severe intracranial and extracranial artery stenosis and were differentially associated with glucose and lipid metabolism in patients with T2DM.Therefore,BTMs may be promising biomarkers and potential therapeutic targets for artery stenosis.

Hepatitis B virus infection in patients with Wilson disease:A large retrospective study

BACKGROUND Wilson disease(WD)is the most common genetic metabolic liver disease.Some studies have shown that comorbidities may have important effects on WD.Data on hepatitis B virus(HBV)infection in patients with WD are limited.AIM To investigate the prevalence and clinical impact of HBV infection in patients with WD.METHODS The clinical data of patients with WD were analyzed retrospectively,and the data of patients with concurrent WD and HBV infection were compared with those of patients with isolated WD.RESULTS Among a total of 915 WD patients recruited,the total prevalence of current and previous HBV infection was 2.1%[95%confidence interval(CI):1.2%-3.0%]and 9.2%(95%CI:7.3%-11.1%),respectively.The main finding of this study was the identification of 19 patients with concurrent WD and chronic hepatitis B(CHB)infection.The diagnosis of WD was missed in all but two patients with CHB infection.The mean delay in the diagnosis of WD in patients with concurrent WD and CHB infection was 32.5 mo,which was significantly longer than that in patients with isolated WD(10.5 mo).The rates of severe liver disease and mortality in patients with concurrent WD and CHB infection were significantly higher than those in patients with isolated WD(63.1%vs 19.3%,P=0.000 and 36.8%vs 4.1%,P<0.001,respectively).Binary logistic regression analysis revealed a significantly higher risk of severe liver disease at the diagnosis of WD in patients with current HBV infection[odds ratio(OR)=7.748;95%CI:2.890-20.774;P=0.000)]or previous HBV infection(OR=5.525;95%CI:3.159-8.739;P=0.000)than in patients with isolated WD.CONCLUSION The total prevalence of current HBV infection in patients with WD was 2.1%.The diagnosis of WD in CHB patients is usually missed.HBV infection is an independent risk factor for severe liver disease in WD patients.The diagnosis of WD should be ruled out in some patients with CHB infection.

Tongmai Yangxin Pill combined with metoprolol or metoprolol alone for the treatment of symptomatic premature ventricular complex:a multicenter,randomized,parallel-controlled clinical study

OBJECTIVE To investigate the effects of Tongmai Yangxin Pill(TMYXP)combined with metoprolol tartrate or metoprolol alone for the treatment of premature ventricular complex(PVC)in patients with symptomatic frequent PVC.METHODS A total of 584 patients with symptomatic frequent PVC were randomly assigned(in a 1:1 ratio)into two groups:study group[n=292,TMYXP(40 pills twice/day,orally)combined with metoprolol tartrate(25 mg twice/day,orally)]and control group[n=292,metoprolol tartrate(25 mg twice/day,orally)plus placebo pill(40 pills twice/day,orally)].The total treatment period was eight weeks.RESULTS After eight weeks of treatment,the total effective rate of reduction of PVC in the study group and the control group were 76.4%and 51.4%,respectively(P<0.001).TMYXP combined with metoprolol tartrate demonstrated a significantly greater reduction of the frequency of PVCs compared with the metoprolol tartrate alone(−4537 times/24 h vs.−3013 times/24 h,P<0.001).The study group also showed a better result compared with the control group with respect to PVC related symptoms.In terms of New York Heart Association classification improvement,the total effective rates were 21.9%in the study group and 12.4%in the control group(P<0.05).Both the study group and the control group exhibited improvements in echocardiographic indexes.Left ventricular ejection fraction was significantly improved in the study group compared with the control group(P<0.05).There was no significant difference in the incidence of adverse events between the two groups.CONCLUSIONS Compared with metoprolol tartrate alone,TMYXP combined with metoprolol tartrate could more effectively reduce the frequency of PVC and alleviated PVC related symptoms,and improve cardiac function in patients with symptomatic PVC.

In-situ hydrothermal synthesis of Ni−MoO_(2)heterostructure on porous bulk NiMo alloy for efficient hydrogen evolution reaction

The Ni−MoO_(2) heterostructure was synthesized in suit on porous bulk NiMo alloy by a facile powder metallurgy and hydrothermal method.The results of field emission scanning electron microscopy(SEM),field emission transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS)reveal that the as-prepared electrode possesses the heterostructure and a layer of Ni(OH)_(2) nanosheets is formed on the surface of Ni−MoO_(2) electrode simultaneously after hydrothermal treatment,which provides abundant interface and much active sites,as well as much active specific surface area.The results of hydrogen evolution reaction indicate that the Ni−MoO_(2) heterostructure electrode exhibits excellent catalytic performance,requiring only 41 mV overpotential to reach the current density of 10 mA/cm^(2).It also possesses a small Tafel slope of 52.7 mV/dec and long-term stability of electrolysis in alkaline medium.

Molecularly imprinted open porous membranes made from Pickering W/O HIPEs for selective adsorption and separation of methyl 4-hydroxybenzoate

In this study, novel molecularly imprinted open porous membranes（MIOPMs） were prepared using the Pickering HIPEs template method and molecular imprinting technology for selective adsorption and separation of methyl 4-hydroxybenzoate（M4HB）. The template M4 HB, functional monomers,crosslinker and plastifier 2-ethylhexyl acrylate（2-EHA） were contained in the oil phase. Hydrophobic silica nanoparticles（HNP-SiO2） were employed as a stabilizer to establish stable W/O Pickering HIPEs with nonionic surfactant sorbitantrioleate（Span 85）. The results of SEM and FTIR indicated that the optimal MIOPMs were prepared successfully and possessed open and interconnecting pores. Then, the MIOPMs were used as sorbents for M4 HB. The correlation coefficient（R^2） values for the Langmuir–Freundlich isotherm model and pseudo-second-order kinetic model fitting to the adsorption equilibrium and kinetic data respectively were all higher than 0.95. The maximum adsorption capacity and the time of rapid adsorption for MIOPM4 were 4.146 mg g^-1 and 100 min, respectively. In addition, the permeability separation factor of MIOPMs for M4 HB compared to a structurally related analog methyl2-hydroxybenzoate（M2HB） could reach 3.122.