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1.
J Helminthol ; 96: e57, 2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35900158

RESUMEN

Steinernema populi n. sp. was recovered by baiting from beneath poplar trees in China. Morphological and molecular features provided evidence for placing the new species into the Kushidai clade. The new species is characterized by the following morphological features: third-stage infective juveniles (IJ) with a body length of 1095 (973-1172) µm, a distance from the anterior end to excretory pore of 77 (70-86) µm and a tail length of 64 (55-72) µm. The Body length/Tail length (c) ratio and Anterior end to Excretory pore/ Tail length × 100 (E%) of S. populi n. sp. are substantially greater than those of all other 'Feltiae-Kushidai-Monticolum' group members. The first-generation males can be recognized by a spicule length of 66 (57-77) µm and a gubernaculum length of 46 (38-60) µm. The new species is further characterized by sequences of the internal transcribed spacer and partial 28S regions of the ribosomal DNA. Phylogenetic analyses show that Steinernema akhursti and Steinernema kushidai are the closest relatives to S. populi n. sp.


Asunto(s)
Rabdítidos , Animales , China , ADN Ribosómico/genética , Masculino , Filogenia
2.
J Chem Phys ; 149(1): 014303, 2018 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-29981542

RESUMEN

Cheaper permanent magnetic nanostructures with magnetic properties equivalent to those of noble-metal or rare-earth nanomagnets have been experimentally developed for their potential applications in ultrahigh storage densities in magnetic memory. To date, their intrinsic magnetic properties are not well understood under the micro-level of local atomic arrangements and electronic structures. In this work, we performed theoretical investigations on the Co3W bulk, the clean surface, nanoclusters, and the Co|Co3W bilayers and superlattices for their geometrical structures, magnetic moments, and magnetic anisotropy energies (MAEs). We found that the Co3W nanostructures we constructed are stable and have the local minima in the energetic landscape, whose stabilities increase with increasing proportion of W and cluster size. The Co and W atoms in clusters are antiferromagnetically coupled, and their local magnetic moments decrease with increasing proportion of W. The breakdown of the Hund's third rule in W atoms observed in experiment can be interpreted as the competition between the intra-atomic spin-orbit coupling in W atoms and interatomic Co-W hybridizations. The highest MAE of about a few tens of meV is obtained in small cluster sizes, whereas it is an order of magnitude reduction in large cluster sizes. The magnetic systems of Co3W clean surface, Co|Co3W bilayer and superlattice can present large MAEs, and their easy-axes of magnetization are perpendicular to the (001) surface. Our calculated MAEs are of the same order of magnitude as that of the experimental measurements, and the electronic origin is revealed through the second-order perturbation method.

3.
J Chem Phys ; 148(7): 074701, 2018 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-29471644

RESUMEN

Magnetism and magnetic anisotropy energy (MAE) of the Ge3Mn5 bulk, free-standing surface, and Ge3Mn5(001)|Ge(111) thinfilms and superlattice have been systemically investigated by using the relativistic first-principles electronic structure calculations. For Ge3Mn5 adlayers on Ge(111) substrates within Mn1 termination, the direction of magnetization undergoes a transition from in-plane at 1 monolayer (ML) thickness (MAE = -0.50 meV/ML) to out-of-plane beginning at 3 ML thickness (nearly invariant MAE = 0.16 meV/ML). The surficial/interfacial MAE is extracted to be 1.23/-0.54 meV for Mn1-termination; the corresponding value is 0.19/1.03 meV for Mn2/Ge-termination; the interior MAE is averaged to be 0.09 meV per ML. For various Ge3Mn5 systems, the in-plane lattice expansion and/or interlayer distance contraction would enhance the out-of-plane MAE. Our theoretical magnetic moments and MAEs fit well with the experimental measurements. Finally, the origination of MAE is elucidated under the framework of second-order perturbation with the electronic structure analyses.

4.
J Anim Sci ; 93(1): 127-34, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25403191

RESUMEN

The aim of this study was to evaluate the effects of antibacterial peptide (ABP) sufficiency on cellular immune functions by determining the spleen cell cycle and apoptosis, peripheral blood T cell subsets, and T cell proliferation function in weaned piglets. A total of 90 piglets (Duroc × Landrace × Yorkshire) of both sexes were randomly allotted to 5 dietary treatments. Each treatment consisted of 3 replicates with 6 piglets per replicate. The dietary treatments consisted of the negative control (NC; basal diet), positive control (PC; basal diet supplemented with 400 mg/kg Astragalus polysaccharide), and ABP (basal diet mixed with 250, 500, and 1,000 mg/kg ABP). The experimental lasted for 28 d. Two piglets from each replicate were selected randomly for blood samples extraction from the jugular vein to obtain peripheral blood T cell subsets, and T cell proliferation function analysis was performed on d 32, 39, 46, and 53. Two piglets from each replicate were selected and euthanized to observe the spleen cell cycle and apoptosis on d 39 and 53. In ABP-sufficient piglets, the G0/G1 phase of the spleen cell cycle was much lower (P < 0.05) and the S and G2 + M phases and proliferation index (PI) were greater (P < 0.05) than in NC piglets. The percentage of apoptotic cells in the spleen significantly decreased under ABP sufficiency (P < 0.05). The proliferation function of peripheral blood T cells increased (P < 0.05) in ABP-sufficient piglets. Percentages of CD3 (+) and CD3 (+)CD4 (+) ratios (d 39, 46, and 53) and CD4 (+)CD8 (+) ratios (d 32, 39, 46, and 53) increased remarkably (P < 0.05) under ABP sufficiency compared with NC. These results suggest that ABP sufficiency could increase the T cell population and proliferation function of T cells and could induce decreased percentages of apoptotic cells. Overall, the cellular immune function was evidently improved in weaned piglets. We suggest optimal dosages of 500 mg/kg ABP for 4-wk addition and 1,000 mg/kg ABP for 2-wk addition.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/farmacología , Inmunidad Celular/inmunología , Sus scrofa/inmunología , Animales , Ciclo Celular/efectos de los fármacos , Dieta/veterinaria , Femenino , Inmunidad Celular/efectos de los fármacos , Activación de Linfocitos/efectos de los fármacos , Masculino , Polisacáridos , Bazo/efectos de los fármacos , Sus scrofa/metabolismo , Subgrupos de Linfocitos T/inmunología
5.
J Phys Chem A ; 118(10): 1936-47, 2014 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-24593697

RESUMEN

Using the density functional theory (DFT) under both frameworks of the local density approximation (LDA) and the generalized gradient approximation (GGA), we show that the anomalous magnetic moment of Tbn (n = 2-20, 22, 33) clusters found in recent experiment [J. Appl. Phys. 2010, 107, 09B526] is due to the antiferromagnetic or ferromagnetic couplings between Tb atoms in clusters. The local spin magnetic moment of Tb atoms is in the range 5.1-5.7 µ(B), which is faintly influenced by the cluster sizes, geometrical structures, and spin arrangements. Emphasis is made on the Tb13 cluster to eliminate the large magnetic discrepancy between the experiment and calculation. Geometrical evolution shows that the square-antiprism motif with one centered atom is competitive with the icosahedral motif for small Tb clusters n = 9-12, whereas the close packed icosahedral growth is clearly favored for large clusters n = 13-20, 22, 33. The clusters containing 4, 7, 10, 13, and 19 atoms are found to be more stable than their neighboring sizes, in agreement with the early mass spectral measurements. The electronic properties including the HOMO-LUMO energy gaps, ionization potentials, electron affinities, and electric dipole moments are calculated, and more importantly, the variational trends of the magnetic moment and electric dipole moment qualitatively fit well with the experimental observations.

6.
J Chem Phys ; 139(20): 204307, 2013 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-24289354

RESUMEN

Theoretical understanding of the stability, ferromagnetism, and spin polarization of Mn5Ge3 clusters has been performed by using the density functional theory with generalized gradient approximation for exchange and correlation. The magnetic moments and magnetic anisotropy energy (MAE) have been calculated for both bulk and clusters, and the enhanced magnetic moment as well as the enlarged MAE have been identified in clusters. The most attractive achievement is that Mn5Ge3 clusters show a fine half-metallic character with large energy scales. The present results may have important implications for potential applications of small Mn5Ge3 clusters as both emerging spintronics and next-generation data-storage technologies.

7.
J Chem Phys ; 139(3): 034314, 2013 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-23883034

RESUMEN

Complementary to the recent experimental finding that the orbital magnetic moment is strongly quenched in small Fe clusters [M. Niemeyer, K. Hirsch, V. Zamudio-Bayer, A. Langenberg, M. Vogel, M. Kossick, C. Ebrecht, K. Egashira, A. Terasaki, T. Möller, B. v. Issendorff, and J. T. Lau, Phys. Rev. Lett. 108, 057201 (2012)], we provide the theoretical understanding of the spin and orbital moments as well as the electronic properties of neutral and cation Fen clusters (n = 2-20) by taking into account the effects of strong electronic correlation, spin-orbit coupling, and noncollinearity of inter-atomic magnetization. The generalized gradient approximation (GGA)+U method is used and its effluence on the magnetic moment is emphasized. We find that without inclusion of the Coulomb interaction U, the spin (orbital) moments have an average value between 2.69 and 3.50 µB/atom (0.04 and 0.08 µB/atom). With inclusion of U, the magnetic value is between 2.75 and 3.80 µB/atom (0.10 and 0.30 µB/atom), which provide an excellent agreement with the experimental measurements. Our results confirm that the spin moments are less quenched, while the orbital moments are strongly quenched in small Fe clusters. Both GGA and GGA+U functionals always yield collinear magnetic ground-state solutions for the fully relaxed Fe structures. Geometrical evolution, as a function of cluster size, illustrates that the icosahedral morphology competes with the hexagonal-antiprism morphology for large Fe clusters. In addition, the calculated trends of ionization potentials, electron affinities, fragment energies, and polarizabilities generally agree with respective experimental observations.

8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 85(4 Pt 2): 046403, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22680582

RESUMEN

An electron injection regime in laser wake-field acceleration, namely electron bow-wave injection, is investigated by two- and three-dimensional particle-in-cell simulation as well as analytical model. In this regime electrons in the intense electron bow wave behind the first bubble catch up with the bubble tail and are trapped by the bubble finally, resulting in considerable enhancement of the total trapped electron number. For example, with the increase of the laser intensity from 2 × 10(19) to 1 × 10(20) W/cm(2), the electron trapping changes from normal self-injection to bow-wave injection and the trapped electron number is enhanced by two orders of magnitude. An analytical model is proposed to explain the numerical observation.

9.
Intern Med J ; 41(6): 481-5, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20059597

RESUMEN

BACKGROUND/AIM: The clinical characteristics of POEMS (polyneuropathy, organomegaly, endocrinopathy, M-protein and skin changes) syndrome in China are largely unknown. This work thus studied the clinical manifestations of POEMS syndrome in China. METHODS: We retrospectively reviewed the medical records of 82 patients with POEMS syndrome in our hospital and made a comparison with those reported outside China. RESULTS: There were 82 patients. Forty (49%) were 45 years old or younger. Sensorimotor deficits were the common initial symptoms. The clinical manifestations are as follows: (i) peripheral neuropathy and abnormal electromyogram were seen in all patients (100%); (ii) organomegaly was present in 72 patients (88%); 61 of them (74%) had splenomegaly; (iii) endocrinopathy was present in 74 cases (90%); hypothyroidism was seen in 51 of 70 patients (73%); (iv) 60 patients (73%) had monoclonal plasmaproliferative disorder; only 22 of 40 (55%) had M-protein; (v) skin changes were seen in 71 patients (87%); (vi) 68 patients (83%) had oedema and effusions; of these, hydropericardium was seen in 23 patients (28%); (vii) 35 of 55 patients (64%) had abnormal electrocardiogram and only 21 of 46 (46%) had bone lesions in X-ray. CONCLUSIONS: POEMS syndrome in China has its own distinctive features, parts of which are commoner in the young people, the higher frequency of splenomegaly, hypothyroidism, hydropericardium and abnormal electrocardiogram, as well as the lower M-protein and bone lesions in X-ray.


Asunto(s)
Glicoproteínas/fisiología , Síndrome POEMS/diagnóstico , Síndrome POEMS/etnología , Adolescente , Adulto , Anciano , China/etnología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome POEMS/clasificación , Estudios Retrospectivos , Enfermedades de la Piel/clasificación , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/etnología , Adulto Joven
10.
Rev Sci Instrum ; 78(11): 113503, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18052470

RESUMEN

A new multichannel HCN interferometer has been developed on HL-2A tokamak, which is characterized by two techniques: (1) the wave-guide HCN laser with cavity length of 6 m to increase the optical resource power and (2) high response room temperature waveguide Schottky diode detectors to obtain good beat signal. The space resolution is 7 cm by the use of focusing metal mirrors mounted on the vacuum chamber and a compensated optical system. In the 2006 experiment campaign, this new interferometer has been applied for plasma density profile and density sawtooth measurement.

11.
Zhongguo Yao Li Xue Bao ; 20(11): 1000-4, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11270964

RESUMEN

AIM: To evaluate the effects of tetrandrine (Tet) and nimodipine (Nim) on the morphine (Mor) withdrawal response in the isolated guinea pig ileum. METHODS: The withdrawal contracture was elicited by addition of naloxone (Nal) (1 mumol.L-1) to the isolated naive ileum incubated with Mor (3 mumol.L-1) at 37.5 degrees C for 4 h or to the ileum obtained from Mor-dependent guinea pig. RESULTS: When Nim (0.01, 0.05, and 0.1 mumol.L-1) or Tet (1, 10, and 50 mumol.L-1) was added 1 min before Nal in the naive ilea bathed in Krebs solution containing Mor, or when the ilea from Mor-dependent guinea pigs were incubated with Nim (0.01, 0.05, and 0.1 mumol.L-1) or Tet (1, 10, and 50 mumol.L-1) for 15 min, or when Nim (5 and 10 mg.kg-1, i.p.) or Tet (15 and 30 mg.kg-1, i.p.) was administered in vivo to Mor-dependent guinea pigs, the Nal-precipitated withdrawal contracture was significantly decreased in a dose-dependent manner. CONCLUSION: Tet and Nim, Ca2+ channel blockers, could inhibit the Nal-precipitated Mor withdrawal response in the isolated guinea pig ileum.


Asunto(s)
Alcaloides/farmacología , Bencilisoquinolinas , Bloqueadores de los Canales de Calcio/farmacología , Dependencia de Morfina/fisiopatología , Contracción Muscular/efectos de los fármacos , Animales , Cobayas , Íleon/efectos de los fármacos , Técnicas In Vitro , Masculino , Músculo Liso/efectos de los fármacos , Nimodipina/farmacología , Síndrome de Abstinencia a Sustancias/fisiopatología
12.
J Foot Ankle Surg ; 32(5): 490-8, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8252007

RESUMEN

The authors review pyrolytic carbon as a biomaterial. Its potential applications in bone and joint surgery are discussed. This manuscript includes work performed in the early 1980s through present day research.


Asunto(s)
Huesos/cirugía , Carbono , Articulaciones/cirugía , Prótesis e Implantes , Materiales Biocompatibles , Humanos , Prótesis Articulares
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