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Cobalt imidazolate frameworks are classical electrocatalysts for the oxygen evolution reaction (OER) but suffer from the relatively low activity. Here, a non‐3d metal modulation strategy is presented for enhancing the OER activity of cobalt imidazolate frameworks. Two isomorphous frameworks [Co4(MO4)(eim)6] (M=Mo or W, Heim=2‐ethylimidazole) having Co(eim)3(MO4) units and high water stabilities were designed and synthesized. In different neutral media, the Mo‐modulated framework coated on a glassy carbon electrode shows the best OER performances (1 mA cm−2 at an overpotential of 210 mV in CO2‐saturated 0.5 m KHCO3 electrolyte and 2/10/22 mA cm−2 at overpotential of 388/490/570 mV in phosphate buffer solution) among non‐precious metal catalysts and even outperforms RuO2. Spectroscopic measurements and computational simulations revealed that the non‐3d metals modulate the electronic structure of Co for optimum reactant/product adsorption and tailor the energy of rate‐determining step to a more moderate value. Non‐3D for 3D: Introducing non‐3d metal oxide units into a cobalt imidazolate framework results in the drastic enhancement of electrocatalytic performance of the oxygen evolution reaction in neutral media. [ABSTRACT FROM AUTHOR]

Cobalt imidazolate frameworks are classical electrocatalysts for the oxygen evolution reaction (OER) but suffer from the relatively low activity. Here, a non‐3d metal modulation strategy is presented for enhancing the OER activity of cobalt imidazolate frameworks. Two isomorphous frameworks [Co4(MO4)(eim)6] (M=Mo or W, Heim=2‐ethylimidazole) having Co(eim)3(MO4) units and high water stabilities were designed and synthesized. In different neutral media, the Mo‐modulated framework coated on a glassy carbon electrode shows the best OER performances (1 mA cm−2 at an overpotential of 210 mV in CO2‐saturated 0.5 m KHCO3 electrolyte and 2/10/22 mA cm−2 at overpotential of 388/490/570 mV in phosphate buffer solution) among non‐precious metal catalysts and even outperforms RuO2. Spectroscopic measurements and computational simulations revealed that the non‐3d metals modulate the electronic structure of Co for optimum reactant/product adsorption and tailor the energy of rate‐determining step to a more moderate value. [ABSTRACT FROM AUTHOR]

(Nd,Pr)-Fe-B powders were mixed with Tb 13 Fe 81 B 6 powders to prepare sintered (Nd,Pr,Tb)-Fe-B magnetic materials. A little amount addition of Tb 13 Fe 81 B 6 powders leads to a faster increase of coercivity, and the coercivity increases from 14.95 kOe to 18.93 kOe at the mass ratio 9.7:0.3 of (Nd,Pr)-Fe-B and Tb 13 Fe 81 B 6 . For the mass ratio of Tb 13 Fe 81 B 6 more than 0.3 the coercivity increases nearly linearly. Both the remanence and the maximum energy product decrease slightly for a little amount addition of Tb 13 Fe 81 B 6 . The investigation by energy dispersive spectrometer shows that though there are dual main phases in the sintered magnets, the chemical compositions of main phase are much different from those of the master alloys due to the atomic diffusion. It is expected to improve the coercivity more largely by optimizing the element distribution in the sintered composite magnets. [ABSTRACT FROM AUTHOR]

In the present study, the magnetic domains and their evolution during magnetization process have been investigated for sintered Nd-Fe-B permanent magnets with Kerr microscopy. Observation of the magnetic domain evolution process during magnetization process shows that some domain walls were pinned at the grain boundary area under magnetic field up to 5 kOe. It is suggested that magnetic interaction between individual Nd2Fe14B grains contacting to each other leads to appearance of small closed domains near the grain boundary area, which are responsible for the pinning effect. [ABSTRACT FROM AUTHOR]

Ce-Fe-B rare-earth alloys are alternative to substitute partially for Nd-Fe-B permanent magnets for reducing the cost and the balance use of rare-earth elements. However, coercivity is rather low in Ce-Fe-B magnets, which partially ascribes to the instability of Ce 2 Fe 14 B phase and the low magnetocrystalline anisotropy. In this paper, magnetic properties are investigated in Ce 13-x Gd x Fe 81 B 6 ribbons via substituting of Gd for Ce. X-ray diffraction shows that a little amount of Gd substitution for Ce leads to an increase in the intensity of diffraction peak for main phase, which should be attributed to the improvement of the stability of R 2 Fe 14 B phase and the reduction in the amount of amorphous phase. Even though the magnetocrystalline anisotropy is lower in Gd 2 Fe 14 B than that in Ce 2 Fe 14 B, the coercivity increases to 5.88 kOe for a little amount of Gd substitution in Ce 12 Gd 1 Fe 81 B 6 ribbons. For Gd atomic percent more than 3% the coercivity decreases, and the remanence drops significantly. With the increase of Gd atomic percent, Curie temperature increases monotonically. Henkel plots indicate that Gd substitution for Ce could enhance the effect of exchange coupling, which owes to the increase of exchange coefficient in main phase as well as to the reduction in the amount of amorphous phase. These investigations show that a little amount substitution of Gd is beneficial to improve the magnetic properties without a significant drop of the remanence. [ABSTRACT FROM AUTHOR]

(Ce,Nd)-Fe-B sintered magnets were prepared by the addition of NdH x powders in Ce 9 Nd 4.5 Fe 80 B 6.5 powders. The coercivity is rather low in Ce 9 Nd 4.5 Fe 80 B 6.5 magnets, and Ce element prefers to distribute at the outer-layer of main phase (Ce,Nd) 2 Fe 14 B. The investigation of scanning electron microscope shows that the addition of NdH x powders leads to the increase of Nd content at grain outer-layer of main phase owing to the element diffusion. Magnetization reversal undergoes the nucleation of reversed domain wall at grain outer-later, and the addition of NdH x powders leads to the increase in the nucleation field of reversed domain, giving rise to the significant improvement of coercivity. The larger amount addition of NdH x powders leads to the increase in the amount of intergranular phase, resulting in the decreases of the remanence, the squareness of demagnetization curve and the maximum energy product. [ABSTRACT FROM AUTHOR]

A series of misch-metal (MM = 28.27 wt % La, 50.46 wt % Ce, 5.22 wt % Pr, 15.66 wt % Nd)-iron-boron isotropic ribbons with atomic formula (MM) 12+x Fe 82-x-y B 6+y (x = 0, 1, 2, 3, 4, y = 0, 0.5, 1, 1.5, 2) are prepared by melt spinning technique. A large energy product ( BH ) max of 12 MGOe is obtained with the composition of MM 13 Fe 81 B 6 at optimized processing. The ribbons with both coercivity larger than 10 kOe and ( BH ) max larger than 10 MGOe are achieved in a wide composition range. All the samples exhibit the tetragonal crystal structure. The magnetization and Henkel plot (δ M ) measurements indicate that the ribbons have a relatively homogeneous microstructure and strong exchange-coupling interactions. The average grain size of the ribbons is around 30 nm determined via Scherrer's formula. Meanwhile, the transmission electron microscope (TEM) image also verifies that the ribbons have a homogeneous nanoscale microstructure. In addition, the spin reorientation temperature T sr is investigated by ac susceptibility χ ac measurement. [ABSTRACT FROM AUTHOR]

High energy ball milling (HEBM) is employed to produce nano-sized grains and particles. In this paper, the structure and magnetic properties are investigated in PrCo5 alloy for HEBM in an ethanol milling medium. With the increase of milling time, the grain size reduces and the coercivity increases. For a milling time of less than 30 min, the hysteresis loop of the aligned sample is very different from that of the un-aligned sample and it does not show a large decrease in magnetization slope, indicating a relatively good alignment of easy axes in particles due to the fact that the texture is nearly well preserved. However, when the milling time is further prolonged, the textured structure deteriorates in the powders. Even though exchange coupling exists between grains within the particle, the magnetic properties are exchange-decoupled between particles and the dipolar interaction results in a negative value of δm in the whole range of the magnetic field. [ABSTRACT FROM AUTHOR]

In this paper, we derive the determinant representation of higher-order algebraic soliton solutions of the Gerdjikov–Ivanov equation by using the Darboux transformation and some limit technique. Based on the asymptotic balance between different algebraic terms, we obtain the asymptotic expressions of algebraic soliton solutions with the order 2 ≤ N ≤ 4. It turns out that all the asymptotic solitons have the same amplitudes, most of them are located in the parabolic curves and thus have the varying velocities with the rate O ( | t | − 1 2 ) (except that one pair of asymptotic solitons are located in the straight lines for the odd-order cases), and they exhibit the elastic interactions of the attractive type. In addition, we reveal that the transient rogue waves are generated in the soliton-interaction region and the peak value is exactly N times the amplitude of individual soliton. • The determinant representation of higher-order algebraic soliton solutions is obtained for the Gerdjikov–Ivanov equation. • The asymptotic analysis method is developed on the balance between different algebraic terms up to the subdominant level. • The asymptotic solitons exhibit the attractive interactions and most of them are located in the parabolic curves. • The transient rogue waves can be generated in the soliton-interaction region. [ABSTRACT FROM AUTHOR]

Background: Hepatitis E is caused by two viral genotype groups: human types and zoonotic types. Current understanding of the epidemiology of the zoonotic hepatitis E disease is founded largely on hospital-based studies. Methods: The epidemiology of hepatitis E was investigated in a community-based surveillance study conducted over one year in a rural city in eastern China with a registered population of 400,162. Results: The seroprevalence of hepatitis E in the cohort was 38%. The incidence of hepatitis E was 2.8/10,000 person-years. Totally 93.5% of the infections were attributed to genotype 4 and the rest, to genotype 1. Hepatitis E accounted for 28.4% (102/359) of the acute hepatitis cases and 68.9% (102/148) of the acute viral hepatitis cases in this area of China. The disease occurred sporadically with a higher prevalence during the cold season and in men, with the male-to-female ratio of 3∶1. Additionally, the incidence of hepatitis E increased with age. Hepatitis B virus carriers have an increased risk of contracting hepatitis E than the general population (OR = 2.5, 95%CI 1.5–4.2). Pre-existing immunity to hepatitis E lowered the risk (relative risk  = 0.34, 95% CI 0.21–0.55) and reduced the severity of the disease. Conclusions: Hepatitis E in the rural population of China is essentially that of a zoonosis due to the genotype 4 virus, the epidemiology of which is similar to that due to the other zoonotic genotype 3 virus. [ABSTRACT FROM AUTHOR]

Background Acceleromyography used to monitor the neuromuscular transmission function is available in infants and children. However, information on the so-called staircase phenomenon during the baseline stabilization period in this population is limited. Our objective was to assess the characteristics of such phenomenon in infants in acceleromyography. Methods Thirty infants were divided into three groups: group A (aged 1-5 months, n = 10), group B (aged 6-11 months, n = 10), and group C (aged 12-24 months, n = 10). Anesthesia was induced and maintained without neuromuscular blocking agents. Patients received a supramaximal stimulus followed by TOF measurements every 15 s over the course of 30 min with a TOF-Watch® SX. All data were collected in a notebook computer using the TOF-Watch® SX Monitor software through optical fibers. Results The evoked T1 responses in younger infants (group A) were significantly lower than those in older infants (groups B and C) from 0-20 min. In group A, the signals increased to the maximum value of 121 ± 15% that of the control at 7.25 min and decreased toward a plateau of 113 ± 18% at 30 min. In group B, the signal heights increased to the maximum value of 143 ± 14% at 9.5 min, then decreased slowly to 136 ± 10% at 19.5 min, finally reaching 116 ± 12% at 30 min. In group C, the mean values of T1 reached the maximum of 139 ± 19% that of control at 9.5 min and finally reached 126 ± 22% of control at 30 min. Conclusions The staircase effect presents in a shorter time course and at lower degrees in smaller infants. However, in older infants, staircase effect still presents in a long period and may influence the onset time and duration of twitch depression after muscle relaxants administration. [ABSTRACT FROM AUTHOR]

Background: There is an urgent need for a vaccine that is effective against the 2009 pandemic influenza A (H1N1) virus. Methods: A split-virus, inactivated candidate vaccine against the 2009 H1N1 virus was manufactured, and we evaluated its safety and immunogenicity in a randomized clinical trial. Subjects were between 3 and 77 years of age, stratified into four age groups. The immunization schedule consisted of two vaccinations, 21 days apart. Subjects were injected with placebo or with vaccine, with or without alum adjuvant, at doses of 7.5 μg, 15 μg, or 30 μg. Serologic analysis was performed at baseline and on days 21 and 35. Results: A total of 2200 subjects received one dose, and 2103 (95.6%) received the second dose, of vaccine or placebo. No severe adverse side effects associated with the vaccine were noted. In the nonadjuvanted-vaccine groups, injection-site or systemic reactions, most mild in nature, were noted in 5.5 to 15.9% of subjects. Among the subjects receiving 15 μg of nonadjuvanted vaccine, a hemagglutination-inhibition titer of 1:40 or more was achieved by day 21 in 74.5% of subjects between 3 and 11 years of age, 97.1% of subjects between 12 and 17 years, 97.1% of subjects between 18 and 60 years, and 79.1% of subjects 61 years of age or older; by day 35, the titer had been achieved in 98.1%, 100%, 97.1%, and 93.3% of subjects, respectively. The proportion with a titer of 1:40 or more was generally highest among the subjects receiving 30 μg of vaccine, with or without adjuvant. Vaccine without adjuvant was associated with fewer local reactions and greater immune responses than was vaccine with adjuvant. Conclusions: These data suggest that a single dose of 15 μg of hemagglutinin antigen without alum adjuvant induces a typically protective immune response in the majority of subjects between 12 and 60 years of age. Lesser immune responses were seen after a single dose of vaccine in younger and older subjects. (ClinicalTrials.gov number, NCT00975572.) N Engl J Med 2009;361:2414-23. [ABSTRACT FROM AUTHOR]

A method for preparing 125I brachytherapy seeds is presented. Carbon bars were used as the substrates, on which a silver coating was deposited by electroless plating, and then, 125I was adsorbed by iodinating the silver coating so as to prepare source cores. The radioactive cores were sealed individually in the titanium capsule to fabricate the 125I brachytherapy seeds. Quality control checking of the encapsulated 125I seeds for dimension, leakage and surface contamination were performed. And the 125I seeds using carbon bar as the core substrate underwent computed tomography (CT) scan and X-ray imaging to determine the visualization. This paper provides valuable experiences and data for the preparation of 125I brachytherapy seeds. [ABSTRACT FROM AUTHOR]

The greater wax moth, Galleria mellonella Linnaeus (Lepidoptera: Galleriinae), is a ubiquitous pest of the honeybee, and poses a serious threat to the global honeybee industry. G. mellonella pheromone system is unusual compared to other lepidopterans and provides a unique olfactory model for pheromone perception. To better understand the olfactory mechanisms in G. mellonella, we conducted a transcriptomic analysis on the antennae of both male and female adults of G. mellonella using high-throughput sequencing and annotated gene families potentially involved in chemoreception. We annotated 46 unigenes coding for odorant receptors, 25 for ionotropic receptors, two for sensory neuron membrane proteins, 22 for odorant binding proteins and 20 for chemosensory proteins. Expressed primarily in antennae were all the 46 odorant receptor unigenes, nine of the 14 ionotropic receptor unigenes, and two of the 22 unigenes coding for odorant binding proteins, suggesting their putative roles in olfaction. The expression of some of the identified unigenes were sex-specific, suggesting that they may have important functions in the reproductive behavior of the insect. Identification of the candidate unigenes and initial analyses on their expression profiles should facilitate functional studies in the future on chemoreception mechanisms in this species and related lepidopteran moths. [ABSTRACT FROM AUTHOR]

Background: Severe hand, foot, and mouth disease (HFMD) is a common childhood illness caused by various enteroviruses. The disease has imposed increased burden on children younger than 5 years old. We aimed to determine the epidemiology, CNS complication, and etiology among severe HFMD patients, in Jiangsu, China.Methods: Epidemiological, clinical, and laboratory data of severe HFMD cases were extracted from 2009 to 2015. The CNS complication, annually severe illness rates, mortality rates, severity-PICU admission rates, severity-hospitalization rates, and so on were analyzed to assess the disease burden of severe HFMD. All analyses were stratified by time, region, population, CNS involvement and serotypes. The VP1 gene from EV-A71, CV-A16, CV-A6, CV-A10 and other enteroviruses isolates was amplified. Phylogenetic analysis was performed using MEGA5.0.Results: Seven thousand nine hundred ninety-four severe HFMD cases were reported, of them, 7224 cases were inpatients, 611 were PICU inpatients, and 68 were fatal. The average severe illness rate, mortality rate, severity-fatality rate, severity-PICU admission rate, and severity-hospitalization rate were 14.54, 0.12,8506, 76,430, and 903,700 per 1 million, respectively. The severe illness rate was the highest in the 12-23 months age group, and the greatest mortality rate was in the 6-11 months age group. Geographical difference in severe illness rate and mortality were found. Patients infected with EV-A71 were at a higher proportion in different CNS involvement even death. EV-A71, CV-A16 and other enteroviruses accounted for 79.14, 6.49, and 14.47%, respectively. A total of 14 non-EV-A71/ CV-A16 genotypes including CV-A2, CV-A4, CV-A 6, CV-A9, CV-A10, CV-B1, CV-B2, CV-B3, CV-B4, CV-B5, E-6, E-7, E-18, and EV-C96 were identified. Phylogentic analyses demonstrated that EV-A71 strains belonged to subgenotype C4a, while CV-A16 strains belonged to sub-genotype B1a and sub-genotype B1b of genotype B1. CV-A6 strains were assigned to genogroup F, and CV-A10 strains belonged to genogroup D.Conclusions: Future mitigation policies should take into account the age, region heterogeneities, CNS conditions and serotype of disease. Additional a more rigorous study between the mild and severe HFMD should be warranted to elucidate the difference epidemiology, pathogen spectrum and immunity patterns and to optimize interventions in the following study. [ABSTRACT FROM AUTHOR]