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Glyphodes pyloalis Walker (Lepidoptera: Pyralididae) is a common pest in sericulture and has developed resistance to different insecticides. However, the mechanisms involved in insecticide resistance of G. pyloalis are poorly understood. Here, we present the first whole-transcriptome analysis of differential expression genes in insecticide-resistant and susceptible G. pyloalis. Clustering and enrichment analysis of DEGs revealed several biological pathways and enriched Gene Ontology terms were related to detoxification or insecticide resistance. Genes involved in insecticide metabolic processes, including cytochrome P450, glutathione S-transferases and carboxylesterase, were identified in the larval midgut of G. pyloalis. Among them, CYP324A19, CYP304F17, CYP6AW1, CYP6AB10, GSTs5, and AChE-like were significantly increased after propoxur treatment, while CYP324A19, CCE001c, and AChE-like were significantly induced by phoxim, suggesting that these genes were involved in insecticide metabolism. Furthermore, the sequence variation analysis identified 21 single nucleotide polymorphisms within CYP9A20, CYP6AB47, and CYP6AW1. Our findings reveal many candidate genes related to insecticide resistance of G. pyloalis. These results provide novel insights into insecticide resistance and facilitate the development of insecticides with greater specificity to G. pyloalis.
The aim of the study was to investigate any association between extrauterine growth restriction (EUGR) and intestinal flora of <30-week-old preterm infants. A total of 59 preterm infants were assigned to EUGR (n=23) and non-EUGR (n=36) groups. Intestinal bacteria were compared by using high-throughput sequencing of bacterial rRNA. The total abundance of bacteria in 344 genera (7568 v. 13,760; P<0.0001) and 456 species (10,032 v. 18,240; P<0.0001) was significantly decreased in the EUGR group compared with the non-EUGR group. After application of a multivariate logistic model and adjusting for potential confounding factors, as well as false-discovery rate corrections, we found four bacterial genera with higher and one bacterial genus with lower abundance in the EUGR group compared with the control group. In addition, the EUGR group showed significantly increased abundances of six species (Streptococcus parasanguinis, Bacterium RB5FF6, two Klebsiella species and Microbacterium), but decreased frequencies of three species (one Acinetobacter species, Endosymbiont_of_Sphenophorus_lev and one Enterobacter_species) compared with the non-EUGR group. Taken together, there were significant changes in the intestinal microflora of preterm infants with EUGR compared to preterm infants without EUGR.
Athetis lepigone (Möschler) (Lepidoptera: Noctuidae) is a new outbreak pest in China. Consequently, it is unclear whether the emergence and spread of the outbreak of this pest are triggered by rapid in situ population size increases in each outbreak area, or by immigrants from a potential source area in China. In order to explore the outbreak process of this pest through a population genetics approach, we developed ten novel polymorphic expressed sequence tags (EST)-derived microsatellites. These new microsatellites had moderately high levels of polymorphism in the tested population. The number of alleles per locus ranged from 3 to 19, with an average of 8.6, and the expected heterozygosity ranged from 0.269 to 0.783. A preliminary population genetic analysis using these new microsatellites revealed a lack of population genetic structure in natural populations of A. lepigone. The estimates of recent migration rate revealed strong gene flow among populations. In conclusion, our study developed the first set of EST-microsatellite markers and shed a new light on the population genetic structure of this pest in China.
A new method, called Cloud of Points (COP) Reconstruction, is proposed in the present work to extend the meshfree method to simulate viscous flows. With the characters of viscous flows, the anisotropic COP structure is distributed in boundary layer. The proposed method can improve the anisotropic COP structure to isotropic COP structure and reduce the condition number of the least square coefficient matrix for conventional meshfree method. The values of the new reconstructed points are calculated by the Lagrange interpolation. The accuracy and the robustness of the presented meshfree solver are demonstrated on a number of standard test cases, including the functions with analytical gradients and the viscous flows past NACA0012 airfoil. The comparison of the simulation results with the experimental data and other numerical simulation data are also investigated.
This study aimed to examine the effectiveness of intratympanic methylprednisolone perfusion as salvage treatment for profound idiopathic sudden sensorineural hearing loss.
A retrospective clinical study of 97 patients with unilateral profound idiopathic sudden sensorineural hearing loss was performed. In all, 83 patients who received salvage intratympanic methylprednisolone perfusion plus conventional treatment (except for steroids) as the second-line therapy were assigned to the study group, while 14 patients who received conventional treatment alone were assigned to the comparison group.
In the study group, treatments in patients with a shorter interval from disease onset to intratympanic methylprednisolone perfusion (up to 15 days) had significantly greater improvements in the overall effective rate and pure tone average compared with patients with a longer interval (over 15 days). For patients with a short interval from disease onset to intratympanic methylprednisolone perfusion, those in the study group had significantly greater improvements in the overall effective rate and pure tone average compared with those in the comparison group. In both the study and comparison groups, hearing improvements were greater at low frequencies than at medium and high frequencies.
The interval from disease onset to intratympanic methylprednisolone perfusion was the major factor affecting hearing recovery. Early second-line salvage intratympanic methylprednisolone perfusion significantly improved the degree of hearing recovery in profound idiopathic sudden sensorineural hearing loss patients after failure of systemic steroid treatment.
The interaction of a relativistic fireball with its ambient medium is described through two shocks: a reverse shock that propagates into the fireball, and a forward shock that propagates into the medium. We here study very early afterglows from the reverse and forward shocks in winds. An optical flash arises from both the relativistic reverse and forward shock while a radio flare is produced by the forward shock.
We investigate whether the circum-burst environment constrained by the absorption feature of GRB990705 could be consistent with the observed H-band afterglow. Two possible geometries of the afterglow-emitting regions are suggested: 1) afterglow emission produced by the impact of the fireball on the surrounding torus; 2)afterglow emission produced in the dense circum-burst medium inside the torus. In case 1), the faster decay at later time is attributed to the disappearance of the shock due to the counter-pressure in the hot torus illuminated by the burst and afterglow photons. For case 2), the circum-burst medium density is found to be very high (n ≳ 104 − 105cm−3).
This study aimed to investigate the long-term efficacy of intratympanic methylprednisolone perfusion treatment for intractable Ménière's disease.
A retrospective analysis of 17 intractable Ménière's disease patients treated with intratympanic methylprednisolone perfusion was performed. Treatment efficacy was evaluated according to the American Academy of Otolaryngology–Head and Neck Surgery criteria. Short and long-term control or improvement rates were calculated after 6 and 24 months, respectively.
Sixteen patients were followed for more than two years. Short- and long-term vertigo control rates were 94 per cent and 81 per cent, respectively; short- and long-term functional activity improvements were 94 per cent and 88 per cent, respectively. The pure tone average was 53 ± 14 dB before treatment, and 50 ± 16 dB at 6 months and 52 ± 20 dB at 24 months after intratympanic methylprednisolone perfusion. Tinnitus was controlled or improved in five patients over the two-year follow-up period.
Intratympanic methylprednisolone perfusion can effectively control vertigo and improve functional activity in intractable Ménière's disease patients with good hearing preservation. It may therefore be a viable alternative treatment for intractable Ménière's disease.
To determine risk factors for sporadic Vibrio parahaemolyticus gastroenteritis, we conducted a population-based case-control study in sentinel hospital surveillance areas of Shanghai and Jiangsu province, China. Seventy-one patients with diarrhoea and confirmed V. parahaemolyticus infections were enrolled, and they were matched with 142 controls for gender, age and residential area. From the multivariable analysis, V. parahaemolyticus infections were associated with antibiotics taken during the 4 weeks prior to illness [odds ratio (OR) 8·1, 95% confidence interval (CI) 1·2–56·4)], frequent eating out (OR 3·3, 95% CI 1·1–10·1), and shellfish consumption (OR 3·2, 95% CI 1·0–9·9), with population-attributable fractions of 0·09, 0·25, and 0·14, respectively. Protective factors included keeping the aquatic products refrigerated (OR 0·4, 95% CI 0·1–0·9) and pork consumption (OR 0·2, 95% CI 0·1–0·8). Further study of the association of V. parahaemolyticus gastroenteritis with prior antibiotic use and shellfish consumption is needed.
Most knowledge regarding the effects of antidepressant drugs is at the receptor level, distal from the nervous system effects that mediate their clinical efficacy. Using functional magnetic resonance imaging (fMRI), this study investigated the effects of escitalopram, a selective serotonin reuptake inhibitor (SSRI), on resting-state brain function in patients with major depressive disorder (MDD).
Fourteen first-episode drug-naive MDD patients completed two fMRI scans before and after 8 weeks of escitalopram therapy. Scans were also acquired in 14 matched healthy subjects. Data were analyzed using the regional homogeneity (ReHo) approach.
Compared to controls, MDD patients before treatment demonstrated decreased ReHo in the frontal (right superior frontal gyrus), temporal (left middle and right inferior temporal gyri), parietal (right precuneus) and occipital (left superior occipital gyrus and right cuneus) cortices, and increased ReHo in the left dorsal medial prefrontal gyrus and left anterior lobe of the cerebellum. Compared to the unmedicated state, ReHo in the patients after treatment was decreased in the left dorsal medial prefrontal gyrus, the right insula and the bilateral thalamus, and increased in the right superior frontal gyrus. Compared to controls, patients after treatment displayed a ReHo decrease in the right precuneus and a ReHo increase in the left anterior lobe of the cerebellum.
Successful treatment with escitalopram may be associated with modulation of resting-state brain activity in regions within the fronto-limbic circuit. This study provides new insight into the effects of antidepressants on functional brain systems in MDD.
The transmission of haemorrhagic fever with renal syndrome (HFRS) is influenced by climatic, reservoir and environmental variables. The epidemiology of the disease was studied over a 6-year period in Changsha. Variables relating to climate, environment, rodent host distribution and disease occurrence were collected monthly and analysed using a time-series adjusted Poisson regression model. It was found that the density of the rodent host and multivariate El Niño Southern Oscillation index had the greatest effect on the transmission of HFRS with lags of 2–6 months. However, a number of climatic and environmental factors played important roles in affecting the density and transmission potential of the rodent host population. It was concluded that the measurement of a number of these variables could be used in disease surveillance to give useful advance warning of potential disease epidemics.
We report the first observation of ultraviolet lasing in ZnO powder and ZnO polycrystalline films grown on amorphous fused silica substrates. In the absence of any fabricated mirrors, laser action occurs in the closed loops formed by multiple optical scattering of light.
To investigate the performance of indirect computed tomography lymphography with iopamidol for detecting cervical lymph node metastases in a tongue VX2 carcinoma model.
Materials and methods:
A metastatic cervical lymph node model was created by implanting VX2 carcinoma suspension into the tongue submucosa of 21 rabbits. Computed tomography images were obtained 1, 3, 5, 10, 15 and 20 minutes after iopamidol injection, on days 11, 14, 21 (six rabbits each) and 28 (three rabbits) after carcinoma transplantation. Computed tomography lymphography was performed, and lymph node filling defects and enhancement characteristics evaluated.
Indirect computed tomography lymphography revealed bilateral enhancement of cervical lymph nodes in all animals, except for one animal imaged on day 28. There was significantly slower evacuation of contrast in metastatic than non-metastatic nodes. A total of 41 enhanced lymph nodes displayed an oval or round shape, or local filling defects. One lymph node with an oval shape was metastatic (one of 11, 9.1 per cent), while 21 nodes with filling defects were metastatic (21/30, 70 per cent). The sensitivity, specificity, accuracy, and positive and negative predictive values when using a filling defect diameter of 1.5 mm as a diagnostic criterion were 86.4, 78.9, 82.9, 82.6 and 83.3 per cent, respectively.
When using indirect computed tomography lymphography to detect metastatic lymph nodes, filling defects and slow evacuation of contrast agent are important diagnostic features.
An array of microdisks with diameter of about 9 μm and spacing of 50 μm has been fabricated by dry etching from a 50 Å/50 Å GaN/AlxGa1-xN (x∼ 0.07) multiple quantum well (MQW) structure grown by reactive molecular beam epitaxy. The as-grown MQWs and the microdisk structures have been studied by picosecond time-resolved photoluminescence (PL) spectroscopy. PL emission spectra and decay dynamics were measured at various temperatures and pump intensities. With respect to the original MQWs, we observe strong enhancement of the transition intensity and lifetime for both the intrinsic and barrier transitions. The intrinsic transition is excitonic at low temperatures and exhibits an approximate 10 fold increase in both lifetime and PL intensity upon formation of the microdisks. The exciton transition magnitude diminishes rapidly with increased temperature however, while the enhanced lifetime shows little change. At room temperature the dominant GaN well transition is found to be band-to-band in nature as evidenced by effective band gap shrinkage and band-filling effects seen within the PL spectrum. The implications of our results to III-Nitride microdisk lasers are discussed.
Mid-infrared vertical cavity surface emitting lasers (VCSELs) using PbSe as the active material and broadband high reflectivity Pb1−xSrxSe/BaF 2 distributed Bragg reflectors (DBR) as bottom and top mirrors were grown by molecular beam epitaxy. By pulsed optical pumping, this first IV-VI semiconductor VCSEL operated up to 290K at a wavelength of 4.5 µm. Further optimization of such VCSELs could lead to room temperature continuos wave operation.
An analytical iterative algorithm for fast computation of
scattering from multiple conductive cylinders is developed. It takes account
of the independent 1st-order, coupling 2nd-order and higher-order
scattering of multiple objects. The 1st-order scattering, as
independent scattering of a single object self, is derived by using the
expansion of cylindrical waves in local coordinate of the object, which are
solved by the boundary conditions. Exciting by the 1st-order scattering
from one object, the 2nd-order scattering of multi-objects are
obtained iteratively using the addition theorem of Hankel function and the
boundary conditions. The same approach is applicable to calculations of the
3rd-order and higher order scattering. It is found that the phase
differences caused by the cylinder centers indicate the scattering wave
interferences of multi-objects. Comparison with numerical MoM results well
validates the analytical iterative algorithm, which significantly
accelerates the scattering computation for wide-band frequencies f and
overall azimuth angles θ over 360°. In order to depress the ringing effect
caused by the abrupt change of scattering field in computed region to zero
field in uncomputed region, the Hamming window is used to make gradual
change of the scattering field to zero. Using FFT and 2D spline
interpolation, discrete scattering data over the
plane yield uniform
discrete data over the X − Y plane. The image reconstruction is finally
performed for multiple conductive cylinders. The image can well identify the
positions and sizes of multi-objects.
The maintenance of a stable stem cell
population in the epidermis is important for robust regeneration
of the stratified epithelium. The population size is usually
regulated by cell secreted extracellular signalling molecules as
well as intracellular molecules. In this paper, a simple model
incorporating both levels of regulation is developed to examine
the balance between growth and differentiation for the stem cell
population. In particular, the dynamics of a known differentiation
regulator c-Myc, its threshold dependent differentiation, and
feedback regulation on maintaining a stable stem cell population
Cuprous oxide (Cu2O) films have been grown on single-crystal MgO(110) substrates by a chemical vapor deposition process in the temperature range 690–790 °C. X-ray diffraction measurements show that phase-pure, highly oriented Cu2O films form at these temperatures. The Cu2O films are observed to grow by an island-formation mechanism on this substrate. Films grown at 690 °C uniformly coat the substrate except for micropores between grains. However, at a growth temperature of 790 °C, an isolated, three-dimensional island morphology develops. Using a transmission electron microscopy and atomic force microscope, both dome- and hut-shaped islands are observed and are shown to be coherent and epitaxial. The isolated, coherent islands form under high mobility growth conditions where geometric strain relaxation occurs before misfit dislocation can be introduced. This rare observation for oxides is attributed to the relatively weak bonding of Cu2O, which also has a relatively low melting temperature.
Interfacial phenomena and microstructure in Ag–Si multilayers with a modulation period of 7.64 nm during annealing from 323 to 573 K were investigated by in situ x-ray diffraction and high-resolution transmission electron microscopy. Uphill and downhill diffusion were observed on annealing. The temperature dependence of the effective diffusion coefficient from 373 K (as to downhill diffusion regime) to 523 K was De = 2.02 × 10−20 exp(−0.24 eV/kBT) m2/s. Diffusion of silicon atoms along silver grain boundaries was proposed as the main diffusion mechanism. After annealing, continuous silver sublayers changed to nanometer-sized silver particles (about 4.5 nm) coated completely by amorphous silicon.