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Farmer training is important to improve weed management practices in tea cultivation. To explore the group characteristics of tea growers, we interviewed 354 growers in Guizhou Province, China. Sixty-one percent of the respondents planted tea for companies or cooperative groups, and 56% managed tea gardens larger than 10 ha. Self-employed tea growers tended to be older and smallholders, and to apply herbicides and conduct weed control less frequently (P < 0.05). Approximately 87% of the respondents conducted weed control two to four times yr−1, 83% spent between $200 and $2,000 ha−1 yr−1 for weed control, and 42% thought weed control costs would decrease by 5 years from this study. Twenty-eight species were mentioned by the respondents as being the most serious. According to canonical correspondence analysis, latitude, altitude, being self-employed or a member of a cooperative, having training experience in tea-garden weed management, and frequency and cost of weed control in tea gardens had significant (P < 0.05) influence on the composition of most troublesome weed species listed by respondents. Among the respondents, 60% had had farmer’s training on weed management in tea gardens. Of these, a significant number (P < 0.05) tended to think weed control costs would decrease, and a nonsignificant number (P > 0.05) tended to conduct weed control more frequently and have lower weed management costs in their tea gardens.
In this paper, the influence of strain rate on the mechanical behavior of high-strength low-alloy (HC420LA) steel were studied. Quasi-static and dynamic tensile experiments were performed with strain rates ranging from 0.001 to 500 s−1 at room temperature. The digital image correlation technique was used to obtain the full-field strain. The experimental results showed that HC420LA steel exhibited positive strain rate sensitivity. Based on experimental results, the modified Johnson–Cook (J–C) model was used to model the constitutive behavior of HC420LA steel. Predictions of the standard and modified J–C models were compared using standard statistical parameters. The modified J–C model showed better agreement with the experimental data. Then, numerical simulation of the representative tensile test at a strain rate of 100 s−1 was performed using the finite element code LS-DYNA. Good correlation between the experimental and numerical simulation results was achieved.
The following paper investigates the prevalence and characteristics of asymptomatic norovirus infection in the population living around oyster farm sites. Two consecutive surveys were conducted from January 2014 to December 2014 and 4549 stool samples were screened during the same time period. The total asymptomatic infection rate was 4.04% (184/4549). Norovirus infection rate was 5.20% in oyster farming population which was significantly higher compared with non-farming population where the infection rate was 3.65% (χ2 = 5.49, P < 0.05). A total of 184 NoV positive samples were identified by real time-quantitative polymerase chain reaction (RT-qPCR) and semi-nested RT-PCR and 136 sequences were obtained. The sequences were clustered into 14 genotypes. GI strains were clustered into six genotypes, including GI.2, GI.3, GI.5, GI.6, GI.8 and GI.9; while GII strains were clustered into GII.2, GII.3, GII.4, GII.5, GII.6, GII.8 and GII.13. GI.9 and GII.17 were the predominant and most prevalent genotypes, respectively. The GII.17 genotype replaced GII.4 becoming the dominant genotype in the oyster farming area in 2014. To sum up, long-term monitoring of asymptomatic infection is crucial for the detection of new variant strains and for identifying outbreaks during the early stage.
Kawasaki disease, which is characterised by systemic vasculitides accompanied by acute fever, is regularly treated by intravenous immunoglobulin to avoid lesion formation in the coronary artery; however, the mechanism of intravenous immunoglobulin therapy is unclear. Hence, we aimed to analyse the global expression profile of serum exosomal proteins before and after administering intravenous immunoglobulin.
Two-dimensional electrophoresis coupled with mass spectrometry analysis was used to identify the differentially expressed proteome of serum exosomes in patients with Kawasaki disease before and after intravenous immunoglobulin therapy.
Our analysis revealed 69 differential protein spots in the Kawasaki disease group with changes larger than 1.5-fold and 59 differential ones in patients after intravenous immunoglobulin therapy compared with the control group. Gene ontology analysis revealed that the acute-phase response disappeared, the functions of the complement system and innate immune response were enhanced, and the antibacterial humoral response pathway of corticosteroids and cardioprotection emerged after administration of intravenous immunoglobulin. Further, we showed that complement C3 and apolipoprotein A-IV levels increased before and decreased after intravenous immunoglobulin therapy and that the insulin-like growth factor-binding protein complex acid labile subunit displayed reverse alteration before and after intravenous immunoglobulin therapy. These observations might be potential indicators of intravenous immunoglobulin function.
Our results show the differential proteomic profile of serum exosomes of patients with Kawasaki disease before and after intravenous immunoglobulin therapy, such as complement C3, apolipoprotein A-IV, and insulin-like growth factor-binding protein complex acid labile subunit. These results may be useful in the identification of markers for monitoring intravenous immunoglobulin therapy in patients with Kawasaki disease.
Even though absorber layers fabricated by different methods may yield comparable efficiencies and appear to be similar under conventional probes, such as low power Raman, PL, XRD, they could in fact be quite different in their microscopic structures. We have developed a novel nondestructive spectroscopy approach, high-power-high-temperature (HPHT) Raman spectroscopy, which is capable of revealing the microscopic structural variations of complex alloys like CZTSe over a large area. CZTSe films prepared by sputtering and co-evaporation methods were examined and compared in both lateral and depth directions. In general, high power (HP) illumination brought qualitatively different changes to the CZTSe samples, not only in the CZTSe Raman peaks but also in the secondary phases, which suggests that there is some subtle microscopic differences between the two types of samples. In addition, 2D Raman mapping revealed a larger spatial extension of the local heating effect caused by HP illumination in the sputtered film, which also indicates that two nominally similar films might have different thermal conductivities. High temperature (HT) measurement, which offers uniform heating as opposed to local heating with high power, further enhances the capability of the approach.
We propose amixed spectral method for heat transfer in unbounded domains, using generalised Hermite functions and Legendre polynomials. Some basic results on the mixed generalised Hermite-Legendre orthogonal approximation are established, which plays important roles in spectral methods for various problems defined on unbounded domains. As an example, the mixed generalised Hermite-Legendre spectral scheme is constructed for anisotropic heat transfer. Its convergence is proven, and some numerical results demonstrate the spectral accuracy of this approach.
A generalised Hermite spectral method for Fisher's equation in genetics with different asymptotic solution behaviour at infinities is proposed, involving a fully discrete scheme using a second order finite difference approximation in the time. The convergence and stability of the scheme are analysed, and some numerical results demonstrate its efficiency and substantiate our theoretical analysis.
Microtubule analysis is of significant value for a better understanding of normal and pathological cellular processes. Although immunofluorescence microscopic techniques have proven useful in the study of microtubules, comparative results commonly rely on a descriptive and subjective visual analysis. We developed an objective and quantitative method based on image processing and analysis of fluorescently labeled microtubular patterns in cultured cells. We used a multi-parameter approach by analyzing four quantifiable characteristics to compose our quantitative feature set. Then we interpreted specific changes in the parameters and revealed the contribution of each feature set using principal component analysis. In addition, we verified that different treatment groups could be clearly discriminated using principal components of the multi-parameter model. High predictive accuracy of four commonly used multi-classification methods confirmed our method. These results demonstrated the effectiveness and efficiency of our method in the analysis of microtubules in fluorescence images. Application of the analytical methods presented here provides information concerning the organization and modification of microtubules, and could aid in the further understanding of structural and functional aspects of microtubules under normal and pathological conditions.
This study investigated whether beginning nonnative learners of Chinese can use phonological and semantic information of radicals to learn the sounds and meanings of new Chinese characters. Thirty-four seventh- and eighth-grade American adolescents, who received intensive Chinese instruction for one semester, were taught 16 compound pseudocharacters paired with novel pictures over three learning trials. After each learning trial, students were asked to produce the sounds and meanings of pseudocharacters in which semantic transparency and phonetic regularity of radicals were manipulated. Results showed a facilitation effect of transparent semantic radicals in learning character meanings in early trials. There was a trend that students learned to read regular and transparent characters better than irregular and opaque characters. The ability to learn orthography–pronunciation association uniquely predicted Chinese word reading after controlling for semantic and phonetic radical knowledge. These findings suggest a predominant use of semantic strategies and the importance of orthography to phonology mappings in learning to read Chinese for beginning nonnative learners of Chinese.
Microtubules of cardiac myocytes depolymerize after a hypoxic insult or treatment with colchicine. However, little attention has been paid to quantifying changes in microtubule distribution when using fluorescent images. We converted fluorescence images of labeled microtubules in H9C2 cardiac myocytes to grayscale images, then filtered the images to remove any noise, and used grayscale histograms to quantify features of the images. The results show that parameters such as the mean, variance, skewness, kurtosis, energy, and entropy can be used to quantitatively describe the distribution of microtubules in cells. Quantitative characteristics of microtubule distribution were similar after culturing cells under hypoxic conditions or after treatment with colchicine. These results parallel those described for neonatal rat cardiac myocytes following ischemia and hypoxia. In addition, we provide a method for internal segmentation of the cells, which revealed that microtubular depolymerization was more evident near the cell membrane following hypoxia or colchicine treatment.
We present stable isotope data (δ18O, δ13C) from a detrital rich stalagmite from Kapsia Cave, the Peloponnese, Greece. The cave is rich in archeological remains and there are reasons to believe that flooding of the cave has directly affected humans using the cave. Using a combination of U–Th and 14C dating to constrain a site-specific correction factor for (232Th/238U) detrital molar ratio, a linear age model was constructed. The age model shows that the stalagmite grew during the period from ca. 950 BC to ca. AD 830. The stable oxygen record from Kapsia indicates cyclical changes of close to 500 yr in precipitation amount, with rapid shifts towards wetter conditions followed by slowly developing aridity. Superimposed on this signal, wetter conditions are inferred around 850, 700, 500 and 400–100 BC, and around AD 160–300 and AD 770; and driest conditions are inferred to have occurred around 450 BC, AD 100–150 and AD 650. Detrital horizons in the stalagmite indicate that three major floods took place in the cave at 500 BC, 70 BC and AD 450. The stable carbon isotope record reflects changes in biological activity being a result of both climate and human activities.
The aim of the present study was to evaluate the effects of lutein and lycopene supplementation on carotid artery intima–media thickness (CAIMT) in subjects with subclinical atherosclerosis. A total of 144 subjects aged 45–68 years were recruited from local communities. All the subjects were randomly assigned to receive 20 mg lutein/d (n 48), 20 mg lutein/d+20 mg lycopene/d (n 48) or placebo (n 48) for 12 months. CAIMT was measured using Doppler ultrasonography at baseline and after 12 months, and serum lutein and lycopene concentrations were determined using HPLC. Serum lutein concentrations increased significantly from 0·34 to 1·96 μmol/l in the lutein group (P< 0·001) and from 0·35 to 1·66 μmol/l in the combination group (P< 0·001). Similarly, serum lycopene concentrations increased significantly from 0·18 to 0·71 μmol/l in the combination group at month 12 (P< 0·001), whereas no significant change was observed in the placebo group. The mean values of CAIMT decreased significantly by 0·035 mm (P= 0·042) and 0·073 mm (P< 0·001) in the lutein and combination groups at month 12, respectively. The change in CAIMT was inversely associated with the increase in serum lutein concentrations (P< 0·05) in both the active treatment groups and with that in serum lycopene concentrations (β = − 0·342, P= 0·031) in the combination group. Lutein and lycopene supplementation significantly increased the serum concentrations of lutein and lycopene with a decrease in CAIMT being associated with both concentrations. In addition, the combination of lutein and lycopene supplementation was more effective than lutein alone for protection against the development of CAIMT in Chinese subjects with subclinical atherosclerosis, and further studies are needed to confirm whether synergistic effects of lutein and lycopene exist.
The objective of the study was to determine the frequency of cerebral microbleeds (CMBs) by using phasesensitive imaging in patients with previous transient ischemic attack (TIA) or stroke who were receiving aspirin treatment.
We retrospectively analyzed 300 outpatients with ischemic cerebrovascular disease: 150 had been receiving aspirin treatment for >1 year (patients), and 150 controls had not previously received aspirin. Cerebral microbleeds were defined by a trained observer (blinded to clinical details) according to results of T2-weighted, T1-weighted, diffusion-weighted, and phase-sensitive magnetic resonance imaging (MRI). Numerous vascular risk factors including white matter hyperintensity (WMH), duration of aspirin treatment, age, hypertension or diabetes mellitus were investigated for a possible association with the presence of CMBs in the two groups.
The frequency of CMBs (60/150 (40%) vs 18/150 (12%); odds ratio 4.899, p <0.0001) and intracerebral hemorrhage (ICH)(42/150 (28%) vs 2/150 (1%); odds ratio 28.778, p <0.0001) were significantly higher in the patients than in the controls. Among patients, those using aspirin for >5 years(42/68 (62%) showed a higher frequency of CMBs than those receiving aspirin for ≤ 5 years(18/82 (22%); odds ratio 5.744, p<0.0001). WMH (p=0.020/0.030, 0.007/0.000) age (p=0.007/0.000) and hypertension (p=0.000/0.033), in patients and controls respectively, were each associated with CMBs.
There was a clear impact of aspirin treatment on CMBs associated with intracerebral hemorrhage in Chinese patients. The frequency of CMBs and hemorrhagic complications was higher in patients treated with long-term aspirin.
A hybrid flexible beam equation with harmonic
disturbance at the end where a rigid tip body is attached is
considered. A simple motor torque feedback control is designed
for which only the measured time-dependent angle of rotation and
its velocity are utilized. It is shown that this control can impel
the amplitude of the attached rigid tip body tending to zero as
time goes to infinity.
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