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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.
A fast numerical method for unsteady aerodynamic calculation of 3D wing is established, which is suitable for the preliminary design. Based on the lifting-line method, the aerodynamic data of the 2D aerofoil obtained by the unsteady CFD simulation is used as the model input to solve the aerodynamic force of the 3D wing. Compared with the traditional steady lifting-line method, the augmented method adopts the unsteady Kutta-Jouowski (K-J) theorem to calculate the circulation and improve the accuracy of the method through the circulation correction. The pitching motion of 3D wing at different aspect ratio and reduction frequencies are studied. The results show that the aerodynamic forces obtained by the augmented lifting-line method have good agreement with the 3D unsteady CFD calculations. Compared with 3D CFD calculation, the calculation efficiency of the improved method is increased by more than 12 times. The improved method has extensive applicability and can be used to estimate the unsteady aerodynamic forces of 3D single or multiple wing configurations.
Clinical assessment for depression, to date, has relied heavily on patients’ retrospective report, which is liable to recall bias.
A number of mobile applications for ecological momentary assessment (EMA) of depressive disorder have been piloted, however, evidence regarding their validity and acceptance is limited.
In this study, we examined the association between Hamilton Rating Scale for Depression (HAM-D) and EMA of depressive symptoms via a smartphone application and demonstrated the level and determinants of utilization.
Our mobile phone application, iHOPE, would perform EMA of depression, anxiety, sleep and cognitive ability. Outpatients with depressive disorder were invited to use iHOPE for 8 weeks. Smartphone usage patterns and clinical characteristics were assessed.
We enrolled 59 outpatients with depression (38 [64.4%] women; mean [SD] age = 37.3 [13.9] years). In 8 weeks, participants interacted with iHOPE for an average of 10.8 (SD = 12.3) days; a trend of decreased frequency of use (P = 0.03) was observed. Scores of HAM-D at baseline was associated with, of the first 14 days, scores of PHQ-9 (P = 0.005), visual analogue scale of depression (P = 0.003) and anxiety.
EMA via mobile technology appears to be valid and feasible for Asian patients with depression. Mobile health has a potential for the assessment of depressive disorder in areas with limited awareness and resource for mental health conditions.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
High ambient temperatures affect animal production and welfare in tropical and sub-tropical regions of the world. Feed intake, growth rate, mortality, egg production, hatchability and other production traits related to the economic success of the poultry industry are adversely affected by severe heat stress. In general, heat stress induces the activity of the neuroendocrine system, resulting in activation of the hypothalamic-pituitary-adrenal (HPA) axis, and elevated corticosterone (CORT) concentrations, which affects metabolism and immune responses. These include negative regulation of metabolic hormones, antibody production and heterophil to lymphocyte (H/L) ratio. Heat stress increases mitochondrial activity, causing reactive species overproduction which disrupts the antioxidant balance, leading to oxidative stress damage of membranes, protein and DNA. Heat stress stimulates the central nervous system (CNS), which significantly reduces daily gain, feed intake and FCR in poultry. Consequently, from an animal husbandry perspective, intervention strategies to relieve heat stress conditions have been the focus of many published studies. This review describes the effect of high temperature on production, behavioural, biochemical and immune responses, including oxidative damage that occur during heat stress in poultry, in broilers and laying hens. Moreover, nutritional interventions to alleviate the negative consequence of heat stress is discussed.
Ortleppascaris sinensis (Nematoda: Ascaridida) is a dominant intestinal nematode of the captive Chinese alligator. However, the epidemiology, molecular ecology and population genetics of this parasite remain largely unexplored. In this study, the complete mitochondrial (mt) genome sequence of O. sinensis was first determined using a polymerase chain reaction (PCR)-based primer-walking strategy, and this is also the first sequencing of the complete mitochondrial genome of a member of the genus Ortleppascaris. The circular mitochondrial genome (13,828 bp) of O. sinensis contained 12 protein-coding, 22 transfer RNA and 2 ribosomal RNA genes, but lacked the ATP synthetase subunit 8 gene. Finally, phylogenetic analysis of mtDNAs indicated that the genus Ortleppascaris should be attributed to the family Heterocheilidae. It is necessary to sequence more mtNDAs of Ortleppascaris nematodes in the future to test and confirm our conclusion. The complete mitochondrial genome sequence of O. sinensis reported here should contribute to molecular diagnosis, epidemiological investigations and ecological studies of O. sinensis and other related Ascaridida nematodes.
A new approach is proposed to analyze Bremsstrahlung X-rays that are emitted from laser-produced plasmas (LPP) and are measured by a stack type spectrometer. This new method is based on a spectral tomographic reconstruction concept with the variational principle for optimization, without referring to the electron energy distribution of a plasma. This approach is applied to the analysis of some experimental data obtained at a few major laser facilities to demonstrate the applicability of the method. Slope temperatures of X-rays from LPP are determined with a two-temperature model, showing different spectral characteristics of X-rays depending on laser properties used in the experiments.
Eukaryote transcription is controlled by regulatory DNA sequences and transcription factors, so transcriptional control of gene plays a pivotal role in gene expression. In this study, we identified the region of the CYP6B6 gene promoter of Helicoverpa armigera which responds to the plant secondary toxicant 2-tridecanone. Transient transfection assay results from five of stepwise deletion fragments linked to the luciferase reporter gene revealed that the promoter activity of each CYP6B6 fragment was significantly higher than that of their basal activity after the Sf9 cells were treated with 2-tridecanone. Among all, the fragment spanning −373 to +405 bp of the CYP6B6 promoter showed an obviously 2-tridecanone inducibility (P<0.0001), which might have the 2-tridecanone responsive element based on promoter activity. Electrophoretic mobility shift assays revealed that the nuclear protein extracted from midgut of the 6th instar larva of H. armigera, reared on 10 mg 2-tridecanone per gram artificial diet for 48 h, could specifically bind to the active region from −373 to 21 bp of the CYP6B6 promoter. The combination feature also appeared when using a shorter fragment from −292 to −154 bp of the CYP6B6 promoter. Taken together, we found a 2-tridecanone core responsive region between −292 and −154 bp of the CYP6B6 promoter. This may lead us to a better understanding of transcriptional mechanism of P450 gene and provide very useful information for the pest control.
To exploit the potential application of the conductive polymers in incorporating with carbon-based materials, polypyrrole (PPY) nanotube and polyaniline (PANI) nanofiber were synthesized and the electrochemical properties were compared. The morphology, texture and chemical structure of PPY and PANI were tested employing SEM, TEM, FTIR and XPS. The results of electrochemical tests demonstrate that the specific capacitance of PPY nanotube is as high as 463 F/g at a current density of 0.3 A/g, much higher than that of PANI nanofiber (243 F/g). Furthermore, at a current density of 0.8 A/g, the capacitance of PPY nanotube is 172 F/g, higher than that of PANI nanofiber (104 F/g). Additionally, after the long-term charge-discharge test at a current density of 1.5 A/g, the preserved capacitance of PPY nanotube is still higher than that of PANI nanofiber (106.5 F/g vs. 75 F/g). The EIS measurement illustrates that the PPY nanotube shows lower contact interface resistance and shorter ion diffusion path than the PANI nanofiber. It suggests that the PPY nanotube is a promising material to be applied in supercapacitor rather than the PANI nanofiber, because of its extended internal cavity surface area and pore volume.
Thioredoxins (Trxs) are widely distributed, small proteins that function in redox regulation in a broad spectrum of cellular reactions. Experimental work with barley, wheat and a legume (Medicago truncatula) has established thioredoxin h (Trx h) as a central regulatory protein in seeds, reducing disulphide (S–S) groups of diverse seed proteins, including storage proteins, enzymes and enzyme inhibitors. Trxs appear to be particularly important in plants, as a large number of genes are present compared to mammalian organisms. In Arabidopsis thaliana there are approximately 20 different genes for classical Trxs, and large Trx gene families have also been found in cereals, such as rice, barley, wheat and sorghum. Extensive evidence indicates that adding Trx, reduced nicotinamide adenine dinucleotide phosphate (NADPH) and NADP-thioredoxin reductase (NTR) to cereal flour or seed preparations reduces disulphide (S–S) linkages of storage proteins. The early in vitro studies have been complemented with transgenic barley seed, overexpressing Trx h in protein bodies of the barley endosperm, which showed accelerated germination and early or enhanced expression of associated enzymes, i.e., α-amylase and pullulanase. Overexpression of Trx h levels in wheat was subsequently shown to (1) enhance protein solubility and digestibility, (2) reduce allergenicity of wheat gliadins, and (3) improve dough quality from poor-quality wheat flour. Most recently, we have demonstrated that down-regulation in wheat of Trx h9, a unique thioredoxin, leads to a reduction in the incidence of pre-harvest sprouting, demonstrated in several varieties over multiple generations with field-grown material. Yield and starch content were increased while baking quality in the high-gluten variety remained unchanged. These observations led to the intriguing question of how changes in the endosperm are communicated to the embryo. Studies of Trx h9, a membrane-associated Trx h that can move from cell to cell, provide suggestive evidence for a role of Trx h9 in intercellular communication of redox state.
There is little information about seed dormancy release and germination behaviour in Vitis amurensis, which is one of the most important wild Vitis species. This work aimed to investigate the dormancy release and germination characteristics and their variation in V. amurensis seed. Seed dormancy was released by: (1) stratification at 5, 10, 15, 20, 25 and 15/5°C, respectively; (2) stratification at 25°C followed by stratification at 5°C; (3) 5°C stratification before or after seed drying; and (4) stratification at a series of relative humidities (RHs) at 5 and 25°C. The freshly harvested and dormancy-released seeds were germinated at three fluctuating and four constant temperatures. In V. amurensis: (1) dormancy release could occur at temperature ≤ 25°C, but was maximal at 5°C for all varieties; (2) dormancy release and induction occurred simultaneously during stratification; (3) the rates of dormancy release and induction were dependent on temperature; (4) seed moisture content affected dormancy release with a temperature-dependent pattern; (5) seeds germinated better at fluctuating temperature than at constant temperature. However, the optimum condition for stratification and germination, the rates of dormancy release and induction, and the response of seeds to warm stratification, to drying and to germination temperature varied significantly among the V. amurensis varieties. Our data imply that seed dormancy and germination in V. amurensis not only have intra-species similarity, but also vary within species, which may be due to differences in environmental conditions at the original growth and cultivated sites.
An atomistic scheme is developed based on constructed n-body potential to investigate the glass-forming composition region and atomic configurations in Ni–Zr–Ti system. The glass-forming ranges derived from the n-body potentials through molecular dynamics simulations for the binary Ni–Zr, Ni–Ti, Zr–Ti, and ternary Ni–Zr–Ti systems turns out to be very compatible with theoretical studies and experimental observations. Moreover, the coordination numbers (CNs), microchemical inhomogeneity parameter, and Honeycutt and Anderson pair analysis are also computed to exam the local atomic configurations during crystal-to-amorphous phase transition. It is found that average total CNs of amorphous phases are significantly larger compared with those in solid solution counterparts, owing to the increased fractions of CNs from 13 to 16. A tendency in forming the chemical short-range orders also exists in binary and ternary metallic glasses in the Ni–Zr–Ti system and icosahedra-related atomic configurations play important role in forming those orders.
Particle beams with uniform and well-confined intensity distributions are desirable in some high power beam applications to prolong the target lifetime or to improve the beam utilization. Three kinds of elements had been proposed for the beam homogenizing, such as octupole, pole-piece magnet, and step-like nonlinear magnets. In this paper, the new type of elements called heteromorphic quadrupole and focus sextupole are proposed. The Gaussian-like multiparticle beam redistribution by the octupole, heteromophic quadrupole, step-like nonlinear magnets, and focus sextupole has been simulated by the POISSON and LEADS code. The best redistribution result is obtained by the focus sextupole, and one of the solutions of redistributing beam with big halo can be that of using the focus sextupole and the heteromorphic quadrupole.
The study of dislocation nucleation has gained increasing attentions recently primarily due to the advancement of small scale mechanical testing methods. Based on the classic Rice model of dislocation nucleation from a crack tip in which the dislocation core is modeled by a continuous slip field, a nonlinear finite element method can be formulated with the interplanar potential as the input, and the development of interplanar slip field can be solved from the resulting boundary value problems. The effects of geometric boundary conditions, loading patterns, etc. can be conveniently determined, as opposed to the time consuming molecular simulations. To validate the method, we compare the simulations results of homogeneous dislocation nucleation and heterogeneous dislocation nucleation from a two-dimensional crack tip to the literature results. As proposed by Rice and Beltz (J. Mech. Phys. Solids, 1994), the activation energy for dislocation nucleation from a three-dimensional crack tip depends on the finite thickness in the direction parallel to the crack tip, which has been successfully reproduced in the finite element simulation results reported here.
An n-body potential is first constructed for the Zr–Al system and proven to be realistic by reproducing a number of important properties of the system. Applying the constructed potential, molecular dynamics simulations, chemical short-range order (CSRO) calculation, and Honeycutt and Anderson (HA) pair analysis are carried out to study the Zr–Al metallic glasses. It is found that for the binary Zr–Al system, metallic glasses are energetically favored to be formed within composition range of 35–75 at.% Al. The calculation shows that the CSRO parameter is negative and could be up to −0.17, remarkably indicating that there exists a chemical short-range order in the Zr–Al metallic glasses. The HA pair analysis also reveals that there are diverse short-range packing units in the Zr–Al metallic glasses, in which icosahedra and icosahedra/face-centered cubic (fcc)-defect structures are predominant.
An n-body Ni–Nb–Ta potential is constructed to conduct molecular dynamics simulations using 129 solid solution models with various compositions. Comparing the relative stability of solid solutions versus their disordered counterparts, simulations determine two critical solid-solubility lines, which define a region in the composition triangle. If an alloy is located inside the defined region, a disordered state is energetically favored; if it is located outside, a crystalline solid solution is preserved. The region is therefore named as the metallic glass-forming region.
Commensurate BaTiO3/SrTiO3 superlattices were grown by reactive molecular-beam epitaxy on four different substrates: TiO2-terminated (001) SrTiO3, (101) DyScO3, (101) GdScO3, and (101) SmScO3. With the aid of reflection high-energy electron diffraction (RHEED), precise single-monolayer doses of BaO, SrO, and TiO2 were deposited sequentially to create commensurate BaTiO3/SrTiO3 superlattices with a variety of periodicities. X-ray diffraction (XRD) measurements exhibit clear superlattice peaks at the expected positions. The rocking curve full width half-maximum of the superlattices was as narrow as 7 arc s (0.002°). High-resolution transmission electron microscopy reveals nearly atomically abrupt interfaces. Temperature-dependent ultraviolet Raman and XRD were used to reveal the paraelectric-to-ferroelectric transition temperature (TC). Our results demonstrate the importance of finite size and strain effects on the TC of BaTiO3/SrTiO3 superlattices. In addition to probing finite size and strain effects, these heterostructures may be relevant for novel phonon devices, including mirrors, filters, and cavities for coherent phonon generation and control.
Glass-forming ability (GFA) in relation to microstructure evolution in the ternary Fe–Nb–B and Fe–Zr–B and quaternary Fe–(Nb,Zr)–B systems was systematically studied in a three-dimensional composition space. Through navigating, it was revealed that alloys with the optimum glass-forming ability (GFA) are coupled with composition regions surrounded by competing crystalline phases. Alloys Fe71Nb6B23, Fe77Zr4B19, and Fe71(Nb0.8Zr0.2)6B23 were illustrated to be the best glass formers in the ternary Fe–Nb–B and Fe–Zr–B systems and the quaternary Fe–(Nb,Zr)–B system, respectively, with a critical size for amorphous formation up to 2 mm. They were compared with the theoretical predictions on the basis of an efficient dense-packing model, and good agreements were obtained.
Ferroelectric domain patterning with an electron beam is demonstrated. Polarization of lead zirconate titanate thin films is shown to be reoriented in both positive and negative directions using piezoresponse force and scanning surface potential microscopy. Reorientation of the ferroelectric domains is a response to the electric field generated by an imbalance of electron emission and trapping at the surface. A threshold of 500 μC/cm2 and a saturation of 1500 μC/cm2 were identified. Regardless of beam energy, the polarization is reoriented negatively for beam currents less than 50 pA and positively for beam currents greater than 1 nA.
A tight-binding Ni–Hf potential is constructed by fitting some of the ground-state properties, such as the cohesive energy, lattice constants, and the elastic constants of some Ni–Hf alloys. The constructed potential is verified to be realistic by reproducing some static and dynamic properties of the system, such as the melting points and thermal expansion coefficients for the pure Ni and Hf as well as some of the equilibrium compounds, through molecular dynamics simulation. Applying the constructed potential, molecular dynamics simulations are performed to compare the relative stability of the face-centered-cubic (fcc)/hexagonal close-packed (hcp) solid solutions to their disordered counterparts as a function of solute concentration. It is found that the solid solutions become unstable and transform into the disordered states spontaneously, when the solute concentrations exceed the two critical solid solubilities, i.e., 25 at.% Ni for hcp Hf-rich solid solution and 18 at.% Hf for fcc Ni-based solid solution, respectively. This allows us to determine that the glass-forming ability/range of the Ni–Hf system is within 25–82 at.% Ni. Interestingly, simulations also reveal for the first time, that two mixed regions exist in which an amorphous phase coexists with a crystalline phase, and at about 18 at.% Ni, the hcp lattice turns into a new metastable phase identified to be face-centered orthorhombic structure.
Selective disassembly is an important issue in industrial and
mechanical engineering for environmentally conscious manufacturing.
This paper presents an intelligent selective disassembly approach based
on ant colony algorithms, which take inspiration from the behavior of
real ant colonies and are used to solve combinatorial optimization
problems. For diverse assemblies, the algorithm generates different
amounts of ants cooperating to find disassembly sequences for selected
components, minimizing the reorientation of assemblies and removal of
components. A candidate list that is composed of feasible disassembly
operations, which are derived from a disassembly matrix of products,
guides sequence construction in the implicit solution space and ensures
the geometric feasibility of sequences. Preliminary implementation
results show the effectiveness of the proposed method.