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A new species of Moniliformis, M. tupaia n. sp. is described using integrated morphological methods (light and scanning electron microscopy) and molecular techniques (sequencing and analysing the nuclear 18S, ITS, 28S regions and mitochondrial cox1 and cox2 genes), based on specimens collected from the intestine of the northern tree shrew Tupaia belangeri chinensis Anderson (Scandentia: Tupaiidae) in China. Phylogenetic analyses show that M. tupaia n. sp. is a sister to M. moniliformis in the genus Moniliformis, and also challenge the systematic status of Nephridiacanthus major. Moniliformis tupaia n. sp. represents the third Moniliformis species reported from China.
The role of Mn oxide in the abiotic formation of humic substances has been well demonstrated. However, information on the effect of crystal structure and surface-chemical characteristics of Mn oxide on this process is limited. In the present study, hexagonal and triclinic birnessites, synthesized in acidic and alkali media, were used to study the influence of the crystal-structure properties of birnessites on the oxidative polymerization of hydroquinone and to elucidate the catalytic mechanism of birnessites in the abiotic formation of humic-like polymers in hydroquinone-birnessite systems. The intermediate and final products formed in solution and solid-residue phases were identified by UV/Visible spectroscopy, atomic absorption spectrometry, Fourier-transform infrared spectroscopy, X-ray diffraction, solid-phase microextraction-gaschromatography-mas ss pectrometry, ion chromatography, and ultrafiltration. The degree of oxidative polymerization of hydroquinone wasenhanced with increase in the interlayer hydrated H+, the average oxidation state (AOS), and the specific surface area of birnessites. The nature of the functional groups of the humic-like polymers formed was, however, almost identical when hydroquinone was catalyzed by hexagonal and triclinic birnessites with similar AOS of Mn. The results indicated that crystal structure and surface-chemistry characteristics have significant influence on the oxidative activity of birnessites and the degree of polymerization of hydroquinone, but have little effect on the abiotic formation mechanism of humic-like polymers. The proposed oxidative polymerization pathway for hydroquinone isthat, asit approachesthe birnessite, it formsp recursor surface complexes. Asa strong oxidant, birnessite accepts an electron from hydroquinone, which is oxidized to 1,4-benzoquinone. The coupling, cleavage, polymerization, and decarboxylation reactionsaccompany the generation of 1,4-benzoquinone, lead to the release of CO2 and carboxylic acid fragments, the generation of rhodochrosite, and the ultimate formation of humic-like polymers. These findings are of fundamental significance in understanding the catalytic role of birnessite and the mechanism for the abiotic formation of humic substances in nature.
The formation of manganese (Mn) oxides is influenced by environmental conditions and, in some red soils, Mn oxides occur as coatings on the surface of kaolinite particles in the form of colloidal films or fine particles. The present study aimed to explore the types of formation mechanisms of Mn oxide minerals on the surface of kaolinite. Mn oxide minerals synthesized by reducing the Mn in KMnO4 with a divalent Mn salt (MnSO4) were examined using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effects of various initial molar ratios of Mn2+/Mn7+ (R = 1:0.67, 1:1, 1:2, and 1:4), cationic species (Na+ or Mg2+), synthesis temperatures (30, 60, and 110°C), and amount of added kaolinite (0.25, 0.5, 1.0, 2.0, and 5.0 g) on the formation of Mn oxides were studied. The results showed that Mn oxide mineral types were affected by the initial R value and the background cation. With decreases in the initial R value, the synthesized minerals transformed from cryptomelane to birnessite. The relative mass ratios of kaolinite to Mn oxide were calculated as 1:0.92, 1:0.63, 1:1.15, and 1:1.63. The sodium cation (Na+) had a greater role than Mg2+ in promoting the dissolution–recrystallization of birnessite to cryptomelane. The synthesis temperature had no effect on mineral types, but Mn content increased as temperature increased. When the amount of added kaolinite was increased from 0.25 to 5.0 g, Mn oxide minerals formed gradually and transformed from birnessite to cryptomelane. This work revealed a possible formation process and reaction mechanism on the surface of kaolinite particles in some red soils.
The burden of mental disorders is increasing worldwide, thus, affecting society and healthcare systems. This study investigated the independent influences of age, period and cohort on the global prevalence of mental disorders from 1990 to 2019; compared them by sex; and predicted the future burden of mental disorders in the next 25 years.
Methods
The age-specific and sex-specific incidence of mental disorders worldwide was analysed according to the general analysis strategy used in the Global Burden of Disease Study in 2019. The incidence and mortality trends of mental disorders from 1990 to 2019 were evaluated through joinpoint regression analysis. The influences of age, period and cohort on the incidence of mental disorders were evaluated with an age–period–cohort model.
Results
From 1990 to 2019, the sex-specific age-standardized incidence and disability-adjusted life years (DALY) rate decreased slightly. Joinpoint regression analysis from 1990 to 2019 indicated four turning points in the male DALY rate and five turning points in the female DALY rate. In analysis of age effects, the relative risk (RR) of incidence and the DALY rate in mental disorders in men and women generally showed an inverted U-shaped pattern with increasing age. In analysis of period effects, the incidence of mental disorders increased gradually over time, and showed a sub-peak in 2004 (RR, 1.006 for males; 95% CI, 1.000–1.012; 1.002 for women, 0.997–1.008). Analysis of cohort effects showed that the incidence and DALY rate decreased in successive birth cohorts. The incidence of mental disorders is expected to decline slightly over the next 25 years, but the number of cases is expected to increase.
Conclusions
Although the age-standardized burden of mental disorders has declined in the past 30 years, the number of new cases and deaths of mental disorders worldwide has increased, and will continue to increase in the near future. Therefore, relevant policies should be used to promote the prevention and management of known risk factors and strengthen the understanding of risk profiles and incidence modes of mental disorders, to help guide future research on control and prevention strategies.
Chronic total coronary occlusion is among the most complex coronary artery diseases. Elevated homocysteine is a risk factor for coronary artery diseases. However, few studies have assessed the relationship between homocysteine and chronic total coronary occlusion.
Methods:
1295 individuals from Southwest China were enrolled in the study. Chronic total coronary occlusion was defined as complete occlusion of coronary artery for more than three months. Homocysteine was divided into quartiles according to its level. Univariate and multivariate logistic regression models, receiver operating characteristic curves, and subgroup analysis were applied to assess the relationship between homocysteine and chronic total coronary occlusion.
Results:
Subjects in the higher homocysteine quartile had a higher rate of chronic total coronary occlusion (P < 0.001). After adjustment, the odds ratio for chronic total coronary occlusion in the highest quartile of homocysteine compared with the lowest was 1.918 (95% confidence interval 1.237–2.972). Homocysteine ≥ 15.2 μmol/L was considered an independent indicator of chronic total coronary occlusion (odds ratio 1.53, 95% confidence interval 1.05–2.23; P = 0.0265). The area under the receiver operating characteristic curve was 0.659 (95% confidence interval, 0.618–0.701; P < 0.001). Stronger associations were observed in elderly and in those with hypertension and diabetes.
Conclusions:
Elevated homocysteine is significantly associated with chronic total coronary occlusion, particularly in elderly and those with hypertension and diabetes.
Maternal syphilis not only seriously affects the quality of life of pregnant women themselves but also may cause various adverse pregnancy outcomes (APOs). This study aimed to analyse the association between the related factors and APOs in maternal syphilis. 7,030 pregnant women infected with syphilis in Henan Province between January 2016 and December 2022 were selected as participants. Information on their demographic and clinical characteristics, treatment status, and pregnancy outcomes was collected. Multivariate logistic regression models and chi-squared automatic interaction detector (CHAID) decision tree models were used to analyse the factors associated with APOs. The multivariate logistic regression results showed that the syphilis infection history (OR = 1.207, 95% CI, 1.035–1.409), the occurrence of abnormality during pregnancy (OR = 5.001, 95% CI, 4.203–5.951), not receiving standard treatment (OR = 1.370, 95% CI, 1.095–1.716), not receiving any treatment (OR = 1.313, 95% CI, 1.105–1.559), and a titre ≥1:8 at diagnosis (OR = 1.350, 95%CI, 1.079–1.690) and before delivery (OR = 1.985, 95%CI, 1.463–2.694) were risk factors. A total of six influencing factors of APOs in syphilis-infected women were screened using the CHAID decision tree model. Integrated prevention measures such as early screening, scientific eugenics assessment, and standard syphilis treatment are of great significance in reducing the incidence of APOs for pregnant women infected with syphilis.
To investigate the association between folate levels and the risk of gestational diabetes mellitus (GDM) risk during the whole pregnancy.
Design:
In this retrospective cohort study of pregnant women, serum folate levels were measured before 24 gestational weeks (GW). GDM was diagnosed between 24th and 28th GW based on the criteria of the International Association of Diabetes and Pregnancy Study Groups. General linear models were performed to examine the association of serum folate with plasma glucose (i.e. linear regressions) and risk of GDM (i.e. log-binomial regressions) after controlling for confounders. Restricted cubic spline regression was conducted to test the dosage–response relationship between serum folate and the risk of GDM.
Setting:
A sigle, urban hospital in Shanghai, China.
Participants:
A total of 42 478 women who received antenatal care from April 2013 to March 2017 were included.
Results:
Consistent positive associations were observed between serum folate and plasma glucose levels (fasting, 1-h, 2-h). The adjusted relative risks (RR) and 95 % CI of GDM across serum folate quartiles were 1·00 (reference), 1·15 (95 % CI (1·04, 1·26)), 1·40 (95 % CI (1·27, 1·54)) and 1·54 (95 % CI (1·40, 1·69)), respectively (P-for-trend < 0·001). The positive association between serum folate and GDM remained when stratified by vitamin B12 (adequate v. deficient groups) and the GW of serum folate measurement (≤13 GW v. >13 GWs)
Conclusions:
The findings of this study may provide important evidence for the public health and clinical guidelines of pregnancy folate supplementation in terms of GDM prevention.
Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a severe and life-threatening complication, characterised by multi-organ failure and high short-term mortality. However, there is limited information on the impact of various comorbidities on HBV-ACLF in a large population. This study aimed to investigate the relationship between comorbidities, complications and mortality. In this retrospective observational study, we identified 2166 cases of HBV-ACLF hospitalised from January 2010 to March 2018. Demographic data from the patients, medical history, treatment, laboratory indices, comorbidities and complications were collected. The mortality rate in our study group was 47.37%. Type 2 diabetes mellitus was the most common comorbidity, followed by alcoholic liver disease. Spontaneous bacterial peritonitis, pneumonia and hepatic encephalopathy (HE) were common in these patients. Diabetes mellitus and hyperthyroidism are risk factors for death within 90 days, together with gastrointestinal bleeding and HE at admission, HE and hepatorenal syndrome during hospitalisation. Knowledge of risk factors can help identify HBV-ACLF patients with a poor prognosis for HBV-ACLF with comorbidities and complications.
We study the asymptotic behaviour of convective heat transfer for turbulent flows in high-porosity fluid-saturated media by two-dimensional high-resolution numerical simulation. The generalized Navier–Stokes equations for incompressible fluid flow and the heat transport equation in porous media at the representative element volume scale are solved by the lattice Boltzmann method, wherein the non-Darcian effects are taken into consideration. The asymptotic behaviour of the Nusselt number $N$ has been revealed for Rayleigh numbers $10^4\leq R\leq 10^{11}$ and Darcy numbers $10^{-6}\leq \xi \leq 10^6$: all the data for various Darcy numbers gradually collapse onto a unique line with increasing Rayleigh number. The asymptote can be well represented by $N=0.146\times R^{0.286}$ for $R>2\times 10^7$, which approaches the relationship for the Rayleigh–Bénard turbulent convection of free fluid flows. The transition can be characterized by a scaling analysis with $R^{}\xi ^{3/2}\sim 1$, below which, however, the data collapse onto the Darcy limit for porous media. The Reynolds number and the Nusselt number both increase with Darcy number above the onset of convection, whereas a premature saturation of the Nusselt number is observed in comparison with that of the Reynolds number. The counter-gradient heat transport by the large-scale flows is quantified, which compensates for the increase of the gradient heat transport with Darcy number. The heat transfer in high-porosity fluid-saturated media with a very small Darcy number $\xi \geq 10^{-6}$ can be comparable to that of free fluid flows for a sufficiently high Rayleigh number $R\geq 10^{11}$.
Giardia duodenalis is a common zoonotic intestinal pathogen. It has been increasingly reported in humans and animals; however, genotyping information for G. duodenalis in captive animals is still limited. This study was conducted to assess the prevalence and multilocus genotyping of G. duodenalis in captive animals in zoological gardens in Shanghai, China. A total of 678 fresh fecal samples were randomly collected from captive animals including non-human primates (NHPs) (n = 190), herbivores (n = 190), carnivores (n = 151), birds (n = 138) and reptiles (n = 9) in a zoo and were examined for the presence of G. duodenalis using nested polymerase chain reaction (nested PCR). All G. duodenalis positive samples were assayed with PCR followed by sequencing at β-giardin (bg), glutamate dehydrogenase (gdh) and triose phosphate isomerase (tpi) genes. In this study, 42 specimens (6.2%) were tested G. duodenalis-positive of the 678 fecal samples examined based on a single locus. A total of 30 (4.4%), 30 (4.4%) and 22 (3.2%) specimens were successfully amplified and sequenced at gdh, tpi and bg loci, respectively. Assemblages A and B were identified with assemblage B dominating in NHPs. Sequence analysis demonstrated that one, two and five new isolates were identified at bg, gdh and tpi loci. DNA sequences and new assemblage-subtypes of zoonotic G. duodenalis assemblages A and B were identified in the current study. Our data indicate the occurrence and molecular diversity of G. duodenalis and the potential zoonotic transmission in captive animals in China.
Background: Antibiotic overuse has led to increasing rates of antibiotic resistant infections and unnecessary antibiotic costs. Clinical pharmacists can play a key role in optimizing appropriate use of antimicrobials and reducing antimicrobial resistance. However, the role of clinical pharmacists in antimicrobial stewardship is new and not well established in Viet Nam. Objective: We evaluated the use of clinical pharmacists for improved antimicrobial prescribing. Methods: We assembled an antibiotic stewardship program (ASP) team consisting of a clinical pharmacist and a specialist in infection prevention and control in a 60-bed medical intensive care unit (MICU) at Hue Central Hospital in central Viet Nam. During January–September 2018, the ASP team collected baseline antibiotic prescribing days of therapy (DOT) for all antibiotics administered in the MICU. Then, from October 2018 through June 2019, the ASP team reviewed daily positive clinical bacterial cultures and susceptibility results for all patients present in the MICU. They reviewed medical charts, including antimicrobial prescriptions, during week days and only if patient was still in the ICU at the time of ASP rounds. The team recommended changes to antibiotic therapy verbally to physicians and left the decision to change antibiotic therapy to their discretion. The ASP team documented whether their recommendations were accepted or rejected. Statistical significance was determined using the Student t test. Results: The ASP team reviewed 160 medical charts and made 169 ASP recommendations: 122 (72%) to continue current treatment; 24 (14%) to monitor drug levels or obtain diagnostic tests; 10 (6%) to discontinue therapy; 6 (4%) to de-escalate therapy; 5 (3%) to adjust doses; and 2 (1%) to broaden therapy. Only 8 of the recommended changes (5%) were declined by the clinicians. The average monthly DOT for all types of antibiotics declined significantly from 2,213 to 1,681 (24% decrease; P = .04). Reductions in DOT for the most common broad-spectrum antibiotics included colistin from 303 to 276 (P = .75); imipenem-cilastatin 434 to 248 (P = .06); doripenem 150 to 144 (P = .85). Piperacillin-tazobactam increased from 122 to 142 (P = 0.75). Conclusions: We demonstrated that daily review of cultures and antibiotic use decreased overall antibiotic prescribing. Given that few recommendations included discontinuation of therapy, ASP rounds likely raised awareness for clinicians to optimize antibiotic use.
The effects of macronutrient intake on obesity are controversial. This research aims to investigate the associations between macronutrient intake and new-onset overweight/obesity. The relationship between the consumption of carbohydrate and total fat and obesity was assessed by the multivariable Cox model in this 11-year cohort, which included 6612 adults (3291 men and 3321 women) who were free of overweight and obesity at baseline. The dietary intake was recorded using a 24-h recall method for three consecutive days. Moreover, substitution models were developed to distinguish the effects of macronutrient composition alteration from energy intake modification. During 7·5 person years (interquartile range 4·3, 10·8) of follow-up, 1807 participants became overweight or obese. After adjusting for risk factors, the hazard ratio (HR) of overweight/obesity in extreme quintiles of fat was 1·48 (quintile 5 v. quintile 1, 95 % CI 1·16, 1·89; Ptrend = 0·02) in women. Additionally, replacing 5 % of energy from carbohydrate with equivalent energy from fat was associated with an estimated 4·3 % (HR 1·043, 95 % CI 1·007, 1·081) increase in overweight/obesity in women. Moreover, dietary carbohydrate was inversely associated with overweight/obesity (quintile 5 v. quintile 1, HR 0·70, 95 % CI 0·55, 0·89; Ptrend = 0·02) in women. Total fat was related to a higher risk of overweight/obesity, whereas high carbohydrate intake was related to a lower risk of overweight/obesity in women, which was not observed in men.
Only 30% or fewer of individuals at clinical high risk (CHR) convert to full psychosis within 2 years. Efforts are thus underway to refine risk identification strategies to increase their predictive power. Our objective was to develop and validate the predictive accuracy and individualized risk components of a mobile app-based psychosis risk calculator (RC) in a CHR sample from the SHARP (ShangHai At Risk for Psychosis) program.
Method
In total, 400 CHR individuals were identified by the Chinese version of the Structured Interview for Prodromal Syndromes. In the first phase of 300 CHR individuals, 196 subjects (65.3%) who completed neurocognitive assessments and had at least a 2-year follow-up assessment were included in the construction of an RC for psychosis. In the second phase of the SHARP sample of 100 subjects, 93 with data integrity were included to validate the performance of the SHARP-RC.
Results
The SHARP-RC showed good discrimination of subsequent transition to psychosis with an AUC of 0.78 (p < 0.001). The individualized risk generated by the SHARP-RC provided a solid estimation of conversion in the independent validation sample, with an AUC of 0.80 (p = 0.003). A risk estimate of 20% or higher had excellent sensitivity (84%) and moderate specificity (63%) for the prediction of psychosis. The relative contribution of individual risk components can be simultaneously generated. The mobile app-based SHARP-RC was developed as a convenient tool for individualized psychosis risk appraisal.
Conclusions
The SHARP-RC provides a practical tool not only for assessing the probability that an individual at CHR will develop full psychosis, but also personal risk components that might be targeted in early intervention.
After MRI studies suggested the efficacy of ethyl-EPA in reducing the progressive brain atrophy in Huntington disease (HD), trials were conducted to test its efficacy as a treatment for HD. Trials that continued for 6 months did not find any significant improvement, urging discontinuation of the drug. However, trials that continued for 12 months indicated improvement of motor functions in these patients.
Methods:
We searched 12 electronic databases to find randomised clinical trials relevant to our inclusion criteria. After screening, only five papers were included. Continuous and binary variables were analysed to compute the pooled mean difference (MD) and risk ratio (RR), respectively. Quality effect model meta-analysis was used as a post hoc analysis for studies at 12 months.
Findings:
Meta-analysis indicated that ethyl-eicosapentaenoic acid (EPA) has no significant effect on any scale of HD at 6 months. At 12 months, two studies suggested significant improvements of the Total Motor Score and Total Motor Score–4 in both fixed and quality effect models [MD = −2.720, 95% CI (−4.76, –.68), p = 0.009; MD = −2.225, 95% CI (−3.842, −0.607), p = 0.007], respectively. Maximal chorea score showed significant results [MD = −1.013, 95% CI (−1.793, −0.233), p = 0.011] in only fixed-effect model, while no improvement was detected for Stroop colour naming test or symbol digit modality.
Conclusion:
Meta-analysis indicated a significant improvement of motor scores only after 12 months. These results should be interpreted cautiously because only two studies had assessed the efficacy of ethyl-EPA after 12 months with one of them having a 6-month open-label phase.
The High-degree Cubature Kalman Filter (HCKF) is proposed as a novel methodology based on the arbitrary degree spherical rule, which can achieve better performance than the traditional Kalman filter. However, it also has a large calculation burden when used in a high-dimension and high-degree of accuracy estimation system. The number of sampling points of an HCKF increases polynomially with increasing state-space dimensions, which further increases the calculation burden. The reduction of the number of the state-space dimensions is the main contribution of this study. A strategy for HCKF based on the partitioning of the state-space and orthogonal principle is introduced, referred to as the Multiple Robust HCKF (MRHCKF). It is shown that this technique can effectively reduce the calculation burden for the high-dimension system with robust performance. Numerical simulations are performed for the example of high-dimension relative position and attitude estimation to show that the proposed method can obtain nearly the same performance as the HCKF, while drastically reducing computational complexity.
Combining density functional theory calculations and temperature programmed desorption (TPD) experiments, the adsorption behavior of various sulfur containing compounds, including C2H5SH, CH3SCH3, tetrahydrothiophene, thiophene, benzothiophene, dibenzothiophene, and their derivatives on the coordinately unsaturated sites of Mo27Sx model nanoparticles, are studied systematically. Sulfur molecules with aromaticity prefer flat adsorption than perpendicular adsorption. The adsorption of nonaromatic molecules is stronger than the perpendicular adsorption of aromatic molecules, but weaker than the flat adsorption of them. With gradual hydrogenation (HYD), the binding affinity in the perpendicular adsorption modes increases, while in flat adsorption modes it increases first, then decreases. Significant steric effects on the adsorption of dimethyldibenzothiophene were revealed in perpendicular adsorption modes. The steric effect, besides weakening adsorption, could also activate the S–C bonds through a compensation effect. Finally, by comparing the theoretical adsorption energies with the TPD results, we suggest that HYD and direct-desulfurization path may happen simultaneously, but on different active sites.
Si-TiN alloys are attractive for use as negative electrodes in Li-ion cells because of the high conductivity, low electrolyte reactivity, and thermal stability of TiN. Here it is shown that Si-TiN alloys with high Si content can surprisingly be made by simply ball milling Si and Ti powders in N2(g); a reaction not predicted by thermodynamics. This offers a low-cost and simple method of synthesizing these attractive materials. The resulting alloys have smaller grain sizes than Si-TiN made by ball milling Si and TiN directly, giving them high thermal stability and improved cycling characteristics in Li cells.
This paper proposes a detailed investigation on the new neural-based feed-forward PID direct force control (FNN-PID-DF) approach applied to a highly nonlinear 2-axes pneumatic artificial muscle (PAM) manipulator in order to ameliorate its force output performance. Founded on the novel inverse neural NARX model dynamically identified to learn well all nonlinear characteristics of the contact force dynamics of the 2-axes PAM-based manipulator, the novel proposed neural FNN-PID-DF force controller is innovatively implemented in order to directly force control the 2-axes PAM robot system used as a rehabilitation device subjected to internal systematic interactions and external contact force deviations. The performance of the experimental tests has proven the advantages and merits of the new force control method compared to the classical PID force control method. The new neural FNN-PID-DF force controller guides the wrist/hand of subject/patient to successfully generate the predefined desired force values.
This work designed a facile preparation for an SiO2/C composite as the anode material for lithium ion battery. Both SiO2 and carbon are amorphous. SiO2 and carbon are mixed uniformly. The SiO2/C composite shows high specific capacity, cycle stability, and rate capability in lithium ion battery charge–discharge test. A stable reversible capacity of 1024 mA h/g at the current density of 100 mA/g is reached. The capacity retains 83% after 100 cycles. The uniform mixture of SiO2 and carbon leads to reduced volume change during the lithiation and delithiation of SiO2, together with the amorphous nature of SiO2 explains the high cycling stability. The carbon coating is a key factor for the high capacity and stability due to the increased electrical conductivity and reduced volume change. The resistance of the solid electrolyte interface film and charge transfer resistance of the SiO2/C composite are much smaller than those of pure carbon, which is a direct proof of the improved conductivity of the material by the carbon coating.
The volatile compounds of crofton weed infested by cotton aphids and sprayed
with MeJA were collected and analyzed by the TCT-GC/MS technique. The
healthy weeds were controls. Seventeen volatiles identified from crofton
weed included green leaf odors, monoterpenes and sequiterpenes, and
oxo-compounds. Camphene, 2-carene, α-phellandrene, ρ-cymene, and
caryophyllene were the major volatiles and constituted about 77% of the
total volatile emissions from the control. In the aphid-infested weeds, no
new induced component was found. Among the terpenes, ρ-cymene increased
markedly in the infested weeds compared with the control, whereas all
sesquiterpenes decreased markedly. Levels of endogenous JA in leaves and
young stems of the aphid-infested weeds were markedly higher than in the
control, whereas both endogenous SA level and ABA level were not
significantly different. MeJA sprayed on crofton weed with the aphid
infestation had a similar effect on volatile emissions. It is suggested that
JA was one of the most important signals in crofton weed and could regulate
the emission of volatile compounds.