Filamentous Fungi-Derived Orsellinic Acid-Sesquiterpene Meroterpenoids: Fungal Sources, Chemical Structures, Bioactivities, and Biosynthesis.

Fungi-derived polyketide-terpenoid hybrids are important meroterpenoid natural products that possess diverse structure scaffolds with a broad spectrum of bioactivities. Herein, we focus on an ever-increasing group of meroterpenoids, orsellinic acid-sesquiterpene hybrids comprised of biosynthetic start unit orsellinic acid coupling to a farnesyl group or/and its modified cyclic products. The review entails the search of China National Knowledge Infrastructure (CNKI), Web of Science, Science Direct, Google Scholar, and PubMed databases up to June 2022. The key terms include "orsellinic acid", "sesquiterpene", "ascochlorin", "ascofuranone", and "Ascochyta viciae", which are combined with the structures of "ascochlorin" and "ascofuranone" drawn by the Reaxys and Scifinder databases. In our search, these orsellinic acid-sesquiterpene hybrids are mainly produced by filamentous fungi. Ascochlorin was the first compound reported in 1968 and isolated from filamentous fungus Ascochyta viciae (synonym: Acremonium egyptiacum; Acremonium sclerotigenum); to date, 71 molecules are discovered from various filamentous fungi inhabiting in a variety of ecological niches. As typical representatives of the hybrid molecules, the biosynthetic pathway of ascofuranone and ascochlorin are discussed. The group of meroterpenoid hybrids exhibits a broad arrange of bioactivities, as highlighted by targeting hDHODH (human dihydroorotate dehydrogenase) inhibition, antitrypanosomal, and antimicrobial activities. This review summarizes the findings related to the structures, fungal sources, bioactivities, and their biosynthesis from 1968 to June 2022.

Sirt1 inhibits renal tubular cell epithelial-mesenchymal transition through YY1 deacetylation in diabetic nephropathy.

Silent information regulator 1 (Sirt1) is a deacetylase, which plays an important role in the occurrence and development of diabetic nephropathy (DN). Our previous study shows that Yin yang 1 (YY1), a widely expressed zinc finger DNA/RNA-binding transcription factor, is a novel regulator of renal fibrosis in diabetic nephropathy. Since the activity of YY1 is regulated via acetylation and deacetylation modification, this study aimed to explore whether Sirt1-induced deacetylation of YY1 mediated high glucose (HG)-induced renal tubular epithelial-mesenchymal transition (EMT) and renal fibrosis in vivo and in vitro. We first confirmed that Sirt1 expression level was significantly decreased in the kidney of db/db mice and in HG-treated HK-2 cells. Diabetes-induced Sirt1 reduction enhanced the level of YY1 acetylation and renal tubular EMT. Then, we manipulated Sirt1 expression in vivo and in vitro by injecting resveratrol (50 mg·kg-1·d-1. ip) to db/db mice for 2 weeks or application of SRT1720 (2.5 µM) in HG-treated HK-2 cells, we found that activation of Sirt1 reversed the renal tubular EMT and YY1 acetylation induced by HG condition. On the contrary, Sirt1 was knocked down in db/m mice or EX527 (1 µM) was added in HK-2 cells, we found that inhibition of Sirt1 exacerbated renal fibrosis in diabetic mice and enhanced level of YY1 acetylation in HK-2 cells. Furthermore, knockdown of YY1 inhibited the ameliorating effect of resveratrol on renal tubular EMT and renal fibrosis in db/db mice. In conclusion, this study demonstrates that Sirt1 plays an important role in renal tubular EMT of DN through mediating deacetylation of YY1.

Quercetin improves nonalcoholic fatty liver by ameliorating inflammation, oxidative stress, and lipid metabolism in db/db mice.

Multiphase pathological processes involve in Type 2 diabetes (T2DM)-induced nonalcoholic fatty liver disease (NAFLD). However, the therapies are quite limited. In the present study, the hepatoprotective effects and underlying mechanisms of quercetin in T2DM-induced NAFLD were investigated. T2DM-induced NAFLD and quercetin treatment models were established in vivo and in vitro. The results revealed that quercetin alleviated serum transaminase levels and markedly reduced T2DM-induced histological alterations of livers. Additionally, quercetin restored superoxide dismutase, catalase, and glutathione content in livers. Not only that, quercetin markedly attenuated T2DM-induced production of interleukin 1 beta, interleukin 6, and TNF-α. Accompanied by the restoration of the increased serum total bile acid (p = .0001) and the decreased liver total bile acid (p = .0005), quercetin could reduce lipid accumulation in the liver of db/db mice. Further mechanism studies showed that farnesoid X receptor 1/Takeda G-protein-coupled receptor 5 signaling pathways was involved in quercetin regulation of lipid metabolism in T2DM-induced NAFLD. In high D-glucose and free fatty acid cocultured HepG2 cells model, quercetin eliminated lipid droplets and restored the upregulated total cholesterol and triglyceride levels. Similar to the findings in mice, quercetin could also activate farnesoid X receptor 1/Takeda G-protein-coupled receptor 5 signaling pathway. These findings suggested that quercetin might be a potentially effective drug for the treatment of T2DM-induced NAFLD.

[The Design of an ATR Probe for Online Monitoring of Biological Process].

The in situ biological process relays on a high performance attenuated total reflection (ATR) probe while ATR technique is a powerful tool for inline analysis. The basic principle and characteristic of the ATR technique was analyzed in this paper. A low cost and high throughout ATR probe was designed which can be inserted into the biological reactor directly with nondestructive and zero delay monitoring. It shows that the online ATR probe has a wide spectrum range, and the collected spectra has a high signal-to-noise ratio, which can be used in in-line quantitative analysis for biological process.

The prognostic value of ERCC1 expression in gastric cancer patients treated with platinum-based chemotherapy: a meta-analysis.

Numerous studies examined the association between excision repair complementation group 1 (ERCC1) expression and the prognosis of gastric cancer patients receiving platinum-based chemotherapy but yielded controversial results. We thus conducted a meta-analysis to quantitatively evaluate the prognostic value of ERCC1 expression in gastric cancer patients receiving platinum-based chemotherapy. A systematic literature search was performed to identify relevant studies in PubMed, Web of Science, Embase, Cochrane Library, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, and WanFang Database up to December 17, 2013. Pooled hazard ratios (HRs) or odds ratios (ORs) with 95 % confidence intervals (CIs) were estimated. Moreover, meta-regression analysis and subgroup analysis were conducted according to ethnicity, HR extraction, detection methods, survival analysis, and quality score. A total of 1,409 patients from 21 studies were subjected to final analysis. Positive/high ERCC1 expression was significantly associated with poorer overall survival (HR, 1.58; 95 % CI, 1.09-2.28), especially in Asians (HR, 1.81; 95 % CI, 1.20-2.73), and lower response rate (OR, 0.26; 95 % CI, 0.18-0.36), but not with clinicopathological features, such as gender (OR, 1.01; 95 % CI, 0.68-1.51), grade (OR, 0.66; 95 % CI, 0.43-1.01), and stage (OR, 1.05; 95 % CI, 0.58-1.90). This meta-analysis suggested that ERCC1 expression might be a useful biomarker to predict response and survival for gastric cancer patients receiving platinum-based chemotherapy, particularly in Asians.

AI-powered mental health communication: Examining the effects of affection expectations on health behavioral intentions.

OBJECTIVES: This study proposed and examined users' expectations of chatbots in mental health communication and compared them with human doctors. Focusing on the affective expectation, we aimed to unveil the impacts of changes in affection on individuals' expectations and behavioral intentions. METHODS: A 2 (chatbot vs. human doctor) x 2 (affective vs. neutral) online experiment (N = 364) was conducted. Participants were asked about their expectations towards communicating health with chatbots and human doctors, watched pre-recorded conversations, and answered questions about expectancy violation toward affection and willingness to further health actions. RESULTS: Individuals have higher expectations from human doctors in almost all aspects. Individuals' expectation of online chat with doctors is more likely to be violated compared with chatbots. Significant results are found on individuals' behavioral intentions, with a greater likelihood of switching to online chatbots when chatbots use an affective approach or doctors use a neutral tone. Individual's past experiences with chatbots play a key role in expectancy violations. CONCLUSION: Individuals have higher expectations of human doctors, but using an affective approach may better meet individuals' expectations toward chatbots and switch their behavioral intentions. PRACTICE IMPLICATIONS: Chatbots that meet expectations can be designed and applied to address mental health concerns.

The Discovery of Acremochlorins O-R from an Acremonium sp. through Integrated Genomic and Molecular Networking.

The fermentation of a soil-derived fungus Acremonium sp. led to the isolation of thirteen ascochlorin congeners through integrated genomic and Global Natural Product Social (GNPS) molecular networking. Among the isolated compounds, we identified two unusual bicyclic types, acremochlorins O (1) and P (2), as well as two linear types, acremochlorin Q (3) and R (4). Compounds 1 and 2 contain an unusual benzopyran moiety and are diastereoisomers of each other, the first reported for the ascochlorins. Additionally, we elucidated the structure of 5, a 4-chloro-5-methylbenzene-1,3-diol with a linear farnesyl side chain, and confirmed the presence of eight known ascochlorin analogs (6-13). The structures were determined by the detailed interpretation of 1D and 2D NMR spectroscopy, MS, and ECD calculations. Compounds 3 and 9 showed potent antibacterial activity against Staphylococcus aureus and Bacillus cereus, with MIC values ranging from 2 to 16 µg/mL.

[Research on Raman spectra quantitative analysis model of ethanol aqueous solution based on net analyte signal].

Raman spectroscopy technique could satisfy industrial field measurement requirements because of the advantages of rapidity and nondestructiveness. Thus, It has been widely used in a variety of quantitative and qualitative analysis fields. The volume ration of alcohol and water in alcoholic beverages, i. e. the ethanol content, is a key factor in the detection of the quality of wine products. The development of the detection system for quick, easy and real-time ethanol content measurement is of great significance for national production. In the present paper, net signal analysis method (NAS) was used in the ethanol content quantitative analysis of Raman spectra from the ethanol aqueous solution. The linear regression model was developed between the net signal of ethanol and its concentration. The results showed that the qualitative analysis method based on net signal analysis was superior to the traditional linear regression method such as the MLR method based on the feature peak intensity and the PLS model. It not only improved the prediction accuracy of the model but also enhanced the robustness of the model. Because the model established by the NAS-MLR method is simple and stable, it is possible to develop the portable measurement instruments in future.

Unsupervised domain adaptation for Covid-19 classification based on balanced slice Wasserstein distance.

Covid-19 has swept the world since 2020, taking millions of lives. In order to seek a rapid diagnosis of Covid-19, deep learning-based Covid-19 classification methods have been extensively developed. However, deep learning relies on many samples with high-quality labels, which is expensive. To this end, we propose a novel unsupervised domain adaptation method to process many different but related Covid-19 X-ray images. Unlike existing unsupervised domain adaptation methods that cannot handle conditional class distributions, we adopt a balanced Slice Wasserstein distance as the metric for unsupervised domain adaptation to solve this problem. Multiple standard datasets for domain adaptation and X-ray datasets of different Covid-19 are adopted to verify the effectiveness of our proposed method. Experimented by cross-adopting multiple datasets as source and target domains, respectively, our proposed method can effectively capture discriminative and domain-invariant representations with better data distribution matching.

Establishment of a nomogram for predicting prolonged mechanical ventilation in cardiovascular surgery patients.

AIMS: This study aimed to develop a nomogram model for predicting prolonged mechanical ventilation (PMV) in patients undergoing cardiovascular surgery. METHODS AND RESULTS: In total, 693 patients undergoing cardiovascular surgery at an Affiliated Hospital of Nantong University between January 2018 and June 2020 were studied. Postoperative PMV was required in 147 patients (21.2%). Logistic regression analysis showed that delirium [odds ratio (OR), 3.063; 95% confidence interval (CI), 1.991-4.713; P < 0.001], intraoperative blood transfusion (OR, 2.489; 95% CI, 1.565-3.960; P < 0.001), obesity (OR, 2.789; 95% CI, 1.543-5.040; P = 0.001), postoperative serum creatinine level (mmol/L; OR, 1.012; 95% CI, 1.007-1.017; P < 0.001), postoperative serum albumin level (g/L; OR, 0.937; 95% CI, 0.902-0.973; P = 0.001), and postoperative total bilirubin level (µmol/L; OR, 1.020; 95% CI, 1.005-1.034; P = 0.008) were independent risk factors for PMV. The area under the receiver operating characteristic curve for our nomogram was found to be 0.770 (95% CI, 0.727-0.813). The goodness-of-fit test indicated that the model fitted the data well (χ2 = 12.480, P = 0.131). After the model was internally validated, the calibration plot demonstrated good performance of the nomogram, as supported by the Harrell concordance index of 0.760. Decision curve analysis demonstrated that the nomogram was clinically useful in identifying patients at risk for PMV. CONCLUSION: We established a new nomogram model that may provide an individual prediction of PMV. This model may provide nurses, social workers, physicians, and administrators with an accurate and objective assessment tool to identify patients at high risk for PMV after cardiovascular surgery.

Prediction model for delirium in patients with cardiovascular surgery: development and validation.

BACKGROUND: The aim of this study was to construct a nomogram model for discriminating the risk of delirium in patients undergoing cardiovascular surgery. METHODS: From January 2017 to June 2020, we collected data from 838 patients who underwent cardiovascular surgery at the Affiliated Hospital of Nantong University. Patients were randomly divided into a training set and a validation set at a 5:5 ratio. A nomogram model was established based on logistic regression. Discrimination and calibration were used to evaluate the predictive performance of the model. RESULTS: The incidence of delirium was 48.3%. A total of 389 patients were in the modelling group, and 449 patients were in the verification group. Logistic regression analysis showed that CPB duration (OR [Formula: see text] 1.004, 95% CI: 1.001-1.008, [Formula: see text] 0.018), postoperative serum sodium (OR [Formula: see text] 1.112, 95% CI: 1.049-1.178, [Formula: see text] 0.001), age (OR [Formula: see text] 1.027, 95% CI: 1.006-1.048, [Formula: see text] 0.011), and postoperative MV (OR [Formula: see text] 1.019, 95% CI: 1.008-1.030, [Formula: see text] 0.001) were independent risk factors. The results showed that AUC[Formula: see text] was 0.712 and that the 95% CI was 0.661-0.762. The Hosmer-Lemeshow goodness of fit test showed that the predicted results of the model were in good agreement with the actual situation ([Formula: see text] 6.200, [Formula: see text] 0.625). The results of verification showed that the AUC[Formula: see text] was 0.705, and the 95% CI was 0.657-0.752. The Hosmer-Lemeshow goodness of fit test results were [Formula: see text] 8.653 and [Formula: see text] 0.372, indicating that the predictive effect of the model is good. CONCLUSIONS: The establishment of the model provides accurate and objective assessment tools for medical staff to start preventing postoperative delirium in a purposeful and focused manner when a patient enters the CSICU after surgery.

Nonenzymatic Self-Assembly Access to Diverse ortho-Quinone Methide-Based Pseudonatural Products.

A nonenzymatic self-assembly program was introduced to explore diverse clavatol-based pseudonatural products (PNPs) in a marine-derived fungus. Intermolecular couplings of the chemoreactive ortho-quinone methide of clavatol with native acceptors led to 14 clavatol-based PNPs with five categories, and compounds 1, 2, 5-10, and 12 are new. In particular, 1 and 2 possessed an unprecedented oxa-angular tetracyclic scaffold with highly oxidized modification and exhibited cytotoxicity. Such a program is proven to be of great advantage in constructing bioactive PNPs.

Clinical significance of simultaneous determination of serum tryptophan and tyrosine in patients with lung cancer.

BACKGROUND: To explore the clinical significance of serum tyrosine (Tyr) and tryptophan (Trp) in patients with lung cancer, we used a simple and efficient method of high-performance liquid chromatography with fluorescence detection (HPLC-FD) that simultaneously measured serum Trp and Tyr contents. METHODS: The concentrations of Tyr and Trp were measured simultaneously by HPLC-FD in the sera of 80 patients with lung cancer and 120 healthy controls. RESULTS: Trp concentrations were significantly lower in patients with lung cancer than in healthy controls (39.26±5.44 vs. 49.93±5.43 µmol/l, respectively; P<0.01), whereas in Tyr concentrations there were no differences with healthy controls (65.38±7.94 vs.66.40±8.55 µmol/l, respectively; P>0.05). In addition, patients in the adenocarcinoma group had significantly lower Trp and Tyr concentrations than those in squamous cell carcinoma group. There was no difference between the early stage and advanced stage of lung cancer. CONCLUSIONS: Determination of serum Trp and Tyr concentrations can be employed to assist the diagnosis of the histotypes of lung cancer and tumor stage. Tyr and Trp as indexes on the lung cancer diagnostic sensitivity, specificity were 54.9, 62.9% and 82.4, 92.1%, Trp is an important and special index for lung cancer diagnosis of which the specificity of diagnosis of lung cancer is more than 92%.

YAP mediates the interaction between the Hippo and PI3K/Akt pathways in mesangial cell proliferation in diabetic nephropathy.

AIMS: Glomerular mesangial cell (MC) proliferation is one of the main pathological changes in diabetic nephropathy (DN), but its mechanism needs further elaboration. The Hippo and PI3K/Akt signalling pathways are involved in the regulation of MC proliferation, but their relationship in hyperglycaemia-induced MC proliferation has not been reported. METHODS: We used db/db mice and high-glucose-cultured mesangial cells to generate a diabetic nephropathy model. An MST1-knockdown plasmid was used to identify whether the PI3K/Akt pathway is linked to the Hippo pathway through MST1. LY294002 and SC79 were used to verify the role of the PI3K/Akt signalling pathway in MC cells. RNA silencing and overexpression were performed by using YAP and PTEN-expression/knockdown plasmids to investigate the function of YAP and PTEN, respectively, in the Hippo and PI3K/Akt signalling pathways. RESULTS: By examining a potential feedback loop, we found decreased phosphorylation of MST1 and Lats1 and increased PI3K/Akt activation in db/db mice and high glucose-treated MCs, along with increased MC proliferation. The results of our gene silencing experiment proved PI3K/Akt-mediated intervention in the Hippo pathway and the regulatory effect of YAP on PI3K/Akt through PTEN. CONCLUSIONS: The Hippo pathway is inhibited under diabetic conditions, leading to YAP activation and promoting MC proliferation. The PI3K/Akt pathway is activated through the inhibitory effect of YAP on its repressor, PTEN. Finally, activation of the PI3K/Akt pathway inhibits the Hippo pathway, resulting in nuclear YAP accumulation and accelerating MC proliferation and DN formation.

Simultaneous determination of serum tryptophan metabolites in patients with systemic lupus erythematosus by high performance liquid chromatography with fluorescence detection.

BACKGROUND: To provide a more comprehensive clinic marker of tryptophan (TRP) catabolism in patients with systemic lupus erythematosus (SLE), we developed a simple and efficient method that simultaneously measured serum TRP, kynurenine (KYN), and kynurenic acid (KYNA) using high performance liquid chromatography with fluorescence detection (HPLC-FD). METHODS: A simple and specific high performance liquid chromatography (HPLC) method was developed for simultaneously quantitative determination of TRP, KYN and KYNA with fluorescence detection (FD) using programmed wavelength and on-column fluorescence derivatization. Thirty patients with SLE and 80 healthy control subjects were analyzed for serum TRP metabolites using the assay we developed. The tryptophan breakdown index (TBI) and neuroprotective ratio (NPR) were calculated. RESULTS: The retention time of KYN, KYNA and TRP were 8.5 min, 13.7 min and 17.6 min, respectively. The linear range for TRP was 0.245-196 micromol/L, the limit of detection (LOD) was 0.001 micromol/L and average recovery was 103.71%. The linear range for KYN was 0.049-98 v/L, the LOD was 0.0245 micromol/L, and average recovery was 97.45%. The linear range for KYNA was 1.05-2093 nmol/L, the LOD was 0.05 nmol/L, and average recovery was 100.60%. Inter-day and intra-day relative standard deviations (SDs) were <5%. Phenylalanine, tyrosine, 5-hydroxytryptamine and creatinine did not interfere with the method. The results showed great differences in TRP, KYN and KYNA contents and TBI between patients with SLE and healthy controls, but little difference in NPR. CONCLUSIONS: The method is simple, fast, accurate, and meets the requirements for simultaneous determination of TRP, KYN and KYNA in serum.

[A path-length correction method on biochemical parameter nondestructive measuring of folium].

Vis/NIR spectroscopy technology is capable of analyzing the content of biochemical parameter in folium rapidly and nondestructively. In the process of spectrum analysis, the variations in path-length between different samples exist, with the random light scattering and leaf thickness perturbations, which influence the precision of quantitative analysis model. In order to resolve this problem, an improved path-length correction method based on Extended Multiplicative Scattering Correction is presented. In this paper, firstly the theory of EMSC algorithm is deduced. EMSC method incorporates both chemical terms and wavelength functions to help realize the efficient separation of path-length and interest concentration. Secondly two experiments were implemented to demonstrate the validity of the method. In Experiment 1, sixteen samples of different thickness but almost the same chlorophyll content were selected, and how the path-length affects the spectrum was compared, after EMSC preprocessing, the variable coefficient of spectrum could approach the repeatability error of spectrometer. In Experiment 2, thirty-two samples of different thickness and chlorophyll content were selected. PLS model established using cross validation was employed to evaluate the efficiency of the presented algorithm. Before the preprocessing, the root mean squared error of prediction is 3.9 SPAD with 5 principal components. After preprocessing, the predicted root mean squared error is 2.2 SPAD with 12 principal components. The results indicate that the improved EMSC preprocessing method could exactly eliminate the spectrum difference caused by the path-length variations between different foliums, enhance the sensitivity of concentration and spectral data, and increase the precision of calibrated model.

Effective Manipulation of Spin Dynamics by Polarization Electric Field in InGaN/GaN Quantum Wells at Room Temperature.

III-nitride wide bandgap semiconductors are favorable materials for developing room temperature spintronic devices. The effective manipulation of spin dynamics is a critical request to realize spin field-effect transistor (FET). In this work, the dependence of the spin relaxation time on external strain-induced polarization electric field is investigated in InGaN/GaN multiple quantum wells (MQWs) by time-resolved Kerr rotation spectroscopy. Owing to the almost canceled two different spin-orbit coupling (SOC), the spin relaxation time as long as 311 ps in the MQWs is obtained at room temperature, being much longer than that in bulk GaN. Furthermore, upon applying an external uniaxial strain, the spin relaxation time decreases sensitively, which originates from the breaking of the SU(2) symmetry. The extracted ratio of the SOC coefficients shows a linear dependence on the external strain, confirming the essential role of the polarization electric field. This effective manipulation of the spin relaxation time sheds light on GaN-based nonballistic spin FET working at room temperature.

Spin relaxation induced by interfacial effects in n-GaN/MgO/Co spin injectors.

Spin relaxation, affected by interfacial effects, is a critical process for electrical spin injection and transport in semiconductor-based spintronics. In this work, the electrical spin injection into n-GaN via n-GaN/MgO/Co tunnel barrier was realized, and the interface-related spin relaxation was investigated by both electrical Hanle effect measurement and time-resolved Kerr rotation (TRKR) spectrum. It was found that the spin relaxation caused by interfacial random magnetostatic field was nearly equal to the intrinsic contributions at low temperature (less than 80 K) and could be suppressed by smoother n-GaN/Co interface. When the interfacial random magnetostatic field was suppressed, the spin relaxation time extracted from the electrical injection process was still shorter than that in bulk conduction band, which was attributed to Rashba spin-orbit coupling (SOC) induced by the interface band bending in the depletion region. Due to thermal activation, luckily, the spin relaxation induced by the interfacial Rashba SOC was suppressed at temperatures higher than 50 K. These results illustrate that (1) spin relaxation time could be as long as 300 ps for GaN and (2) the influences of interfacial effects could be engineered to further prolong spin relaxation time, both of which shed lights on GaN-based spintronic devices with direct and wide bandgap.

[Effects of different corn varieties on development and reproduction of Spodoptera frugiperda]. / 不同品种玉米对草地贪夜蛾生长发育及繁殖的影响.

To understand the damage capability of the invasive pest Spodoptera frugiperda on diffe-rent corn varieties in China, we evaluated survival fitness of S. frugiperda on three varieties of sweet corn (i.e., Suitian No.1, Zhengtian 68, and Huajintian No.1) and three varieties of waxy corn (i.e., Jingkenuo 2000, Guangheitiannuo, and Guangnuo No.1) by constructing life table for all populations. The correlation of biological parameters of S. frugiperda to the main nutrients and crude fiber content in corn leaves were analyzed. Results showed that the larva survival rate, pupal weight, and production of S. frugiperda on sweet corns were significantly higher than those on waxy corns. The intrinsic rate of increase (rm) of S. frugiperda on the sweet corns ranged from 0.1566 to 0.1843, and the net reproductive rate (R0) ranged from 187.97 to 353.35, being higher than those reared on the waxy corns (rm was from 0.0998 to 0.1465, and R0 was from 25.89 to 95.34). S. frugiperda reared on the sweet corns had higher population growth ability than those reared on the waxy corns. The content of main nutrients such as vitamin C, starch, soluble sugar, protein, fat, total amino acids, and crude fiber in the sweet corn leaves were higher than those in the waxy corn leaves. There were positive correlations between R0 of S. frugiperda to the contenst of vitamin C, starch, soluble sugar, protein, and crude fiber in corn leaves. The results indicated that S. frugiperda reared on the sweet corn leaves had higher survival fitness than those reared on the waxy corn leaves.

[Chlorophyll content nondestructive measurement method based on Vis/NIR spectroscopy].

In the present paper a method based on Vis/NIR spectral analysis technology was applied to the nondestructive measurement of plant chlorophyll content. Firstly, the Vis/NIR spectra in the wavelength range from 500 to 900 nm of the plant leaves were acquired from 35 samples by transmittance and reflectance method, and then three different mathematical treatments were used in original spectra data pretreatment to decrease the noise: moving average smoothing with the segment size 5, first Savitzky-Golay derivative, and wavelet transform (WT) way. Secondly, a total of 35 samples were examined in the test, in which 23 samples were selected randomly for model building and the other 12 for model prediction, then partial least squares (PLS) method was used to develop the quantitative analysis model for chlorophyll content with absorbance spectroscopy, and 7 principal components (PCs) were selected. Finally, this model was used to predict the chlorophyll content of 12 unknown leaf samples in prediction collection. The experiment result indicated that the better prediction performance was achieved with the correlation coefficient between the prediction values and the truth values being 0.93, and the root mean squared error of prediction is about 1.1 SPAD. It could be concluded that it is feasible to measure plant chlorophyll content based on visible/near infrared (Vis/NIR) spectroscopy. And it is also significant in realizing rapid and nondestructive measurement of chlorophyll content in the future.