Overall quality changes and deterioration mechanism of fragrant rapeseed oils during 6-Month storage

The strong-fragrant rapeseed oil (SFRO) is a popular rapeseed oil in China with a low refining degree only degumming with hot water, which remarkably affects its storage stability. The present study compared the overall changes of physical/chemical/nutrient quality of FROs at various temperatures, light wavelengths and headspace volumes. Results showed that red light (680 nm) had a most significant adverse effect on the overall quality of SFRO with the higher correlation coefficients to PV and TOTOX of 0.71 and 0.70, and lower correlation coefficients to chlorophyll and tocopherol of -0.95 and -0.53, respectively. Further studies revealed that red light accelerated the oxidation of fragrant rapeseed oils by degrading chlorophyll to initiate the photo-oxidation process and synthesize high amount of secondary oxidation products including aliphatic and aromatic oxidized compounds from linolenic acid. These findings provided a reference to control the deterioration of FROs by preventing the transmittance of red light.

Pan-Genomic Analysis Identifies the Chinese Strain as a New Subspecies of Xanthomonas fragariae

Xanthomonas fragariae is classified as a quarantine pathogen by the European and Mediterranean Plant Protection Organization. It commonly induces typical angular leaf spot (ALS) symptoms in strawberry leaves. X. fragariae strains from China (YL19, SHAQP01, and YLX21) exhibit ALS symptoms in leaves and more severe symptoms of dry cavity rot in strawberry crowns. Conversely, strains from other countries do not cause severe dry cavity rot symptoms in strawberries. After employing multilocus sequence analysis (MLSA), average nucleotide identity (ANI), and amino acid identity (AAI), we determined that Chinese strains of X. fragariae are genetically distinct from other strains and can be considered a new subspecies. Subsequent analysis of 63 X. fragariae genomes published at NCBI using IPGA and EDGAR3.0 revealed the pan-genomic profile, with 1,680 shared genes present in all 63 strains, including 71 virulence-related genes. Additionally, we identified 123 genes exclusive to all the Chinese strains, encompassing 12 virulence-related genes. The qRT-PCR analysis demonstrated that the expression of XopD, XopG1, CE8, GT2, and GH121 out of 12 virulence-related genes of Chinese strains (YL19) exhibited a constant increase in the early stages (6, 24, 54, and 96 hours postinoculation [hpi]) of strawberry leaf infected by YL19. So, the presence of XopD, XopG1, CE8, GT2, and GH121 in Chinese strains may play important roles in the early infection process of Chinese strains. These findings offer novel insights into comprehending the population structure and variation in the pathogenic capacity of X. fragariae.

Systemic Colonization of Xanthomonas fragariae Strain YL19 Causing Dry Cavity Rot of Strawberry Crown Tissue in China

Xanthomonas fragariae usually causes angular leaf spot (ALS) of strawberry, a serious bacterial disease in many strawberry-producing regions worldwide. Recently, a new strain of X. fragariae (YL19) was isolated from strawberry in China and has been shown to cause dry cavity rot in strawberry crown. In this study, we constructed a green fluorescent protein (GFP)-labeled Xf YL19 (YL19-GFP) to visualize the infection process and pathogen colonization in strawberries. Foliar inoculation of YL19-GFP resulted in the pathogen migrating from the leaves to the crown, whereas dip inoculation of wounded crowns or roots resulted in the migration of bacteria from the crowns or roots to the leaves. These two invasion types both resulted in the systematic spread of YL19-GFP, but inoculation of a wounded crown was more harmful to the strawberry plant than foliar inoculation. Results increased our understanding of the systemic invasion of X. fragariae, and the resultant crown cavity caused by Xf YL19.

A point mutation in the gene encoding Mg-chelatase subunit I influences strawberry leaf color and metabolism

Magnesium chelatase catalyzes the insertion of magnesium into protoporphyrin IX, a vital step in chlorophyll biogenesis. The enzyme consists of three subunits, (Magnesium chelatase I subunit, CHLI), (Magnesium chelatase D subunit, CHLD) and (Magnesium chelatase H subunit, CHLH). The CHLI subunit is an ATPase that mediates catalysis. Previous studies on CHLI have mainly focused on model plant species, and its functions in other species have not been well described, especially with regard to leaf coloration and metabolism. In this study, we identified and characterized a CHLI mutant in strawberry species Fragaria pentaphylla. The mutant, noted as p240, exhibits yellow-green leaves and a low chlorophyll (Chl) level. RNA-seq identified a mutation in the 186th amino acid of the CHLI subunit, a base conserved in most photosynthetic organisms. Transient transformation of wild-type CHLI into p240 leaves complemented the mutant phenotype. Further mutants generated from RNA-interference (RNAi) and CRISPR/Cas9 gene editing recapitulated the mutant phenotype. Notably, heterozygous chli mutants accumulated more chlorophyll under low light conditions compared to high light conditions. Metabolite analysis of null mutants under high light conditions revealed substantial changes in both nitrogen and carbon metabolism. Further analysis indicated that mutation in Glu186 of CHLI does not affect its subcellular localization, nor the interaction between CHLI and CHLD. However, intramolecular interactions were impaired, leading to reduced ATPase and magnesium chelatase activity. These findings demonstrate that Glu186 plays a key role in enzyme function, affecting leaf coloration via the formation of the hexameric ring itself, and that manipulation of CHLI may be a means to improve strawberry plant fitness and photosynthetic efficiency under low light conditions.

[Effect of diurnal temperature range on the number of elderly inpatients with ischemic stroke in Hunan Province]

Objective: To study the effect of diurnal temperature range on the number of elderly inpatients with ischemic stroke in Hunan Province. Method: Demographic and disease data, meteorological data, air quality data, population, economic and health resource data of elderly inpatients with ischemic stroke were collected in 122 districts/counties of Hunan Province from January to December 2019. The relationships between the diurnal temperature range and the number of elderly inpatients with ischemic stroke were analyzed by using the distributed lag non-linear model, including the cumulative lag effect of the diurnal temperature range in different seasons, extremely high diurnal temperature range and extremely low diurnal temperature range. Results: In 2019, 152 875 person-times were admitted to the hospital for ischemic stroke in the elderly in Hunan Province. There was a non-linear relationship between the diurnal temperature range and the number of elderly patients with ischemic stroke, with different lag periods. In spring and winter, with the decrease in diurnal temperature range, the risk of admission of elderly patients with ischemic stroke increased (P_trend<0.001, P_trend=0.002);in summer, with the increase in diurnal temperature range, the risk of admission of elderly patients with ischemic stroke increased (P_trend=0.024);in autumn, the change in the diurnal temperature range would not cause a change in admission risk (P_trend=0.089). Except that the lag effect of the extremely low diurnal temperature range in autumn was not obvious, the lag effect occurred in other seasons under extremely low and extremely high diurnal temperature ranges. Conclusion: The high diurnal temperature range in summer and the low diurnal temperature range in spring and winter will increase the risk of admission of elderly patients with ischemic stroke, and the risk of admission of elderly patients with ischemic stroke will lag under the extremely low and extremely high diurnal temperature ranges in the above three seasons.

[Analysis of risk factors for readmission of pneumoconiosis patients in Hunan]

Objective: To explore the risk factors of pneumoconiosis patients' re-admission to provide a scientific basis for improving the treatment effect of pneumoconiosis, reducing the rate of re-admission, and reducing the burden of disease. Methods: In June 2020, The clinical data of 470 patients with pneumoconiosis who had hospitalization records from February 8, 2014, to February 8, 2020, in the Hunan Provincial Occupational Disease Prevention and Treatment Institute were retrospectively analyzed. The patients' general data and emotional state at the first admission were collected through questionnaires and telephone follow-ups. The entire group of patients completed at least one follow-up, with readmission as the end event. First, the Kaplan-Meier method was used for univariate analysis. The multivariate COX regression model analysis was performed on meaningful variables to explore the risk factors that affect the patient's re-admission. Results: A total of 470 patients with pneumoconiosis were included in this study, with an average age of 55.88 years (34-81 years old) and all the participants were male. During the first admission, the number of participants diagnosed as stage III pneumoconiosis, with complications of COPD, fatty liver, or severe pulmonary diffusion dysfunction was 215 (45.74%) , 179 (38.09%) , 51 (10.85%) , and 44 (9.36%) , respectively. Six patients (1.28%) have had suicidal tendencies almost every day since they became ill. A total of 345 patients (73.40%) were re-admitted to the hospital. Multivariate Cox regression model analysis showed that compared with the suspected pneumoconiosis group, patients in the first, second, and third-stage pneumoconiosis groups had an increased risk of readmission (OR=2.43, 2.96, 2.35, P=0.000) . Compared with the age of 30-50 years old, 50-70 years old and ≥70 years old have an increased risk of readmission (OR=1.28, 2.32, P<0.05) . Patients with tricuspid regurgitation (OR=1.33, P<0.05) and elevated triglyceride level (>2.26 mmol/L) (OR=1.40, P<0.05) have increased risks of readmission. Compared with the normal group, patients with severe pulmonary diffusion dysfunction in pneumoconiosis have an increased risk of readmission (OR=1.96, P<0.05) . Compared with the normal group, pneumoconiosis patients in the suicidal group had an increased risk of re-admission to the hospital almost every day (OR=2.92, P<0.05) . Conclusion Age of onset, stage of pneumoconiosis, tricuspid regurgitation, high triglycerides, severe diffuse pulmonary dysfunction, and suicidal tendency are independent risk factors that affect the readmission of patients with pneumoconiosis. The management of chronic diseases and mental health of patients with pneumoconiosis should be strengthened to reduce the risk of readmission. Conclusion: Age of onset, stage of pneumoconiosis, tricuspid regurgitation, high triglycerides, severe diffuse pulmonary dysfunction, and suicidal tendency are independent risk factors that affect the readmission of patients with pneumoconiosis. The management of chronic diseases and the mental health of patients with pneumoconiosis should be strengthened to reduce the risk of readmission.

[Epidemiological characteristics of newly reported HIV-infected cases aged 50 years and above in Henan province, 1995-2020]

Objective: To analyze the epidemiological characteristics of newly reported HIV-infected cases aged 50 years and above in Henan province during 1995-2020, and to provide evidence for strategies on HIV/AIDS prevention and control. Methods: Information about newly reported HIV-infected cases aged 50 years and above in Henan between 1995 and 2020 were collected from the National Comprehensive HIV/AIDS Information System. The demographic and behavioral characteristics of HIV-infected cases aged ≥50 were analyzed, and the mixed linear model based on CD4⁺ T lymphocyte (CD4) counts back calculation was used to estimate the years, time and age of the HIV infection. Results: During 1995-2020, a total of 25 038 HIV-infected cases aged 50 years and above were newly reported, accounting for 25.8% (25 038/96 867) of the total number of newly reported HIV-infected cases in Henan. The proportion of newly reported cases over 50-years-old gradually increased from 4.5% (18/396) in 1995-2000 to 35.5% (9 666/27 239) in 2016-2020, with statistically significant difference (χ²=3 105.53, P<0.001). Among them, the proportion of HIV-infected cases aged 60 years and above were increasing year by year. The proportion of male cases were increasing along with ageing. The proportion of HIV-infected cases detected by medical institutions also showed an upward trend. The newly reported HIV-infected cases aged 50 years and above were mainly transmitted through sexual contact. The proportion of heterosexual transmission increased from 5.5% (1/18) in 1995-2000 to 86.2% (8 334/9 666) in 2016-2020, and the proportion of MSM-behavior-related transmission increased from 0.0% in 1995-2000 to 13.5% (1 304/9 666) in 2016-2020. The majority of cases had extra-marital and/or non-commercial heterosexual behavior (48.1%, 4 007/8 334) and the proportion showed an upward trend. The majority of male cases had commercial heterosexual behavior (54.9%, 3 169/5 775), and with increasing proportion along with the increase of age. The majority of female cases had extra-marital and/or non-commercial heterosexual behavior (62.5%, 1 600/2 559), with increasing proportion of extra-marital and/or non-commercial heterosexual behavior. The proportion of heterosexual behavior with spouse or stable sexual partners showed a downward trend. The estimations based on CD4 counts back calculation model showed that among the newly reported HIV-infected cases aged 50 years and above, the average age being infected was (54.8±10.2) years, with 33.8% (4 263/12 621) infected before 50. The interval between infection and diagnosis was (5.7±6.2) years, of which 52.6% (6 636/12 621) were infected for 5 years or longer and 34.7% (4 384/12 621) were in the last 3 years. There was no linear correlation trend in the composition of infection years among the newly reported HIV-infected cases over 50-years-old. Conclusions: In Henan, from 1995 to 2020, the number of newly reported HIV-infected cases aged 50 years and above was increasing and sexual transmission becoming the main transmission route. The increase of prevalence was mostly seen in 60-years-old men, low education level and detected mainly by medical institutions. For this age group, the focus of HIV/AIDS prevention and control should target on those who were transmitted through extra-marital and/or non-commercial heterosexual, commercial heterosexual and MSM behavior and it is necessary to strengthen the HIV testing and detection in this population and in the elderly floating group.

Identifying C2H4N4 structural isomers using fs-laser induced breakdown spectroscopy

Four C2H4N4 structural isomers are investigated with fs laser-induced breakdown spectroscopy. Plasma emissions, C I, Hα, the CN violet system (B2Σ+-X2Σ+, Δν = 0 sequence) and C2 swan system (d3Πg-a3Πu, Δν = 0 sequence) are measured. The temporal evolution of the characteristic emission intensity is obtained for each emission and their lifetimes are calculated. The lifetimes of the molecular emissions are much longer than those of the atomic emissions. Characteristic emission intensities and lifetime are correlated with the molecular structures of the four isomers to a certain extent. Plasma temperature is extracted by fitting the spectrum of the CN violet system, B2Σ+-X2Σ+; Δν = 0 sequence, and is weakly correlated with the molecular structures of the four isomers. Using the characteristic emission intensities as input, principal component analysis (PCA) and artificial neural network (ANN) analysis are performed and the individual isomers can be well identified with PCA or ANN.

CN and C2 formation mechanisms in fs-laser induced breakdown of nitromethane in Ar or N2 atmosphere

We investigate atomic and molecular emission of laser-ablated nitromethane in an Ar or N₂ buffer gas, with fs laser-induced breakdown spectroscopy. The electronic bands of CN, C₂, and NH molecules and the atomic transition lines of C I, N I, and Hα are identified. The time series of the emissions are obtained, and the formation mechanisms of CN and C₂ are deduced. The CN violet system, the B²Σ⁺-X²Σ⁺ (0-0) band, is chosen to extract plasma temperature from the experimental spectra.

[Study on the mechanism of serotype conversion of historical isolates of Shigella flexneri]

Objective: The serotype screening of Shigella flexneri from 1934 to 1965 preserved by the National Center for Medical Culture Collections was carried out, and the molecular characteristics of the serotype conversion strains were studied. Methods: Serotyping of Shigella flexneri in this study was conducted by slide agglutination and multiplex PCR, respectively. The gtrⅡ gene sequence alignment and pulsed field gel electrophoresis typing were performed on the serotype conversion strains. Results: Among the 255 strains of Shigella flexneri preserved in CMCC (B) from 1934 to 1965, 79 were carrying gtrⅡ gene, of which 19 strains and 1 strain were agglutinated with the Y serotype and X serotype, respectively, and furthermore, the multiplex PCR assays results showed serotypes 2a and 2b, respectively, and the strains were considered to have serotype conversion. The 20 strains carrying the gtrⅡ gene showed multiple nucleotide mutations. Besides 3 strains of 3 amino acid mutations, the amino acid sequences of the other 17 strains showed a stop codon in advance, resulting in functional inactivation of gtrⅡ. PFGE analysis revealed that the similarity between the serotype Y strain carrying the gtrⅡ gene and the serotype 2a strain was 75.8%-100%, and the similarity between the serotype X strain carrying the gtrⅡ gene and the serotype 2b strain was 81.6%-100%. Conclusion: Mutations in the gtrⅡ gene are more complicated in serotype-transforming Shigella flexneri serotype Y or X strains. Molecular typing suggests that the serotype-transforming Shigella flexneri serotype Y or X strains may be derived from the Shigella flexneri serotype 2a or 2b, and advance the serotype conversion to 1949.

Theoretical Investigation on Hydrogen Abstraction by NO2 from Symmetric Ethers (CH3)2 xO ( x = 1-4)

Hydrogen abstractions by NO₂ from symmetric ethers are investigated to determine the rate constants and explore the effect of the functional group on rate constants at different reaction sites. The involved ethers are dimethyl ether (DME), diethyl ether (DEE), dipropyl ether (DPE), and dibutyl ether (DBE). The B3LYP method with a 6-31G(2df,p) basis set is employed to optimize the ground-state geometries and for frequency and intrinsic reaction coordinate calculations. The G4 method is used to calculate the electronic energies for the small ethers (DME and DEE). Given the heavy computational cost of the G4 method, the modified G4MP2 method is applied for larger ethers (DPE and DBE) and also for DME to verify the accuracy of the G4MP2 method by benchmarking with the G4 method. The high-pressure limit rate constants are calculated within the temperature range of 500-2000 K, with the asymmetrical Eckart tunneling correction as well as one-dimensional hindered rotor treatment. The calculated rate constants agree well with the literature data, and the branch ratio analysis suggests that the cis-HONO channel basically dominates the hydrogen abstraction reactions and shows a decrease at high temperatures, followed by HNO₂ and trans-HONO channels; in addition, the hydrogen abstraction at the C site adjacent to the ether bond (α reaction site) accounts for most of the reactions. Furthermore, the total rate constants of the ethers are compared to those of their half-structurally alkanes, and linear Bell-Evans-Polanyi correlations are observed.

[Study of the microwave emissivity characteristics of vegetation over the Northern Hemisphere]

The microwave emissivity is a function of structure, water content, and surface roughness, and all these factors have obvious seasonal variations. In the present study, the half-month averaged emissivities in summer and winter of 2003 over the vegetation of Northern Hemisphere were estimated using Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) combined with IGBP (International Geosphere-Biosphere Project labels) land classification data. Then the emissivities of vegetation land covers at different frequencies, the polarization and their seasonal variations were analyzed respectively. The results show that the emissivities of vegetation increase with the increase in frequencies, and decline with the frequency increasing over snow region. In summer, the vegetation emissivity at V-polarization of 89 GHz is larger than 0.944, and all emissivities are relatively stable and the RMSE of time series emissivity variation is less than 0.007 2. In winter, emissivities decrease over snow covered area, especially for higher frequencies. Furthermore, with the increase in vegetation density, the emissivities increase and emissivity polarization difference decreases.

[The relationship between the variation rate of MODIS land surface temperature and AMSR-E soil moisture and its application to downscaling]

Using AMSR-E soil moisture, MODIS land surface temperature (Ts) and vegetation index product, the authors discuss the relationship between the variation rate of land surface temperature and surface soil moisture. Selecting the plains region of central United States as the study area, the authors propose the distribution triangle of the variation rate of land surface temperature and soil moisture. In the present paper, temperature variation and vegetation index (TVVI), a new index containing the information of temperature variation and vegetation, is introduced. The authors prove that TVVI and soil moisture show a steady relationship of exponential function; and build a quantitative model of soil moisture(SM) and instantaneous surface temperature variation (VTs). The authors later achieve downscaling of AMSR-E soil moisture data, through the above stated functional relationships and high-resolution MODIS data. Comparison with measured data on ground surface indicates that this method of downscaling is of high precision

[Study of the microwave emissivity characteristics over different land cover types]

The microwave emissivity over land is very important for describing the characteristics of the lands, and it is also a key factor for retrieving the parameters of land and atmosphere. Different land covers have their emission behavior as a function of structure, water content, and surface roughness. In the present study the global land surface emissivities were calculated using six month (June, 2003-August, 2003, Dec, 2003-Feb, 2004) AMSR-E L2A brightness temperature, MODIS land surface temperature and the layered atmosphere temperature, and humidity and pressure profiles data retrieved from MODIS/Aqua under clear sky conditions. With the information of IGBP land cover types, "pure" pixels were used, which are defined when the fraction cover of each land type is larger than 85%. Then, the emissivity of sixteen land covers at different frequencies, polarization and their seasonal variation were analyzed respectively. The results show that the emissivity of vegetation including forests, grasslands and croplands is higher than that over bare soil, and the polarization difference of vegetation is smaller than that of bare soil. In summer, the emissivity of vegetation is relatively stable because it is in bloom, therefore the authors can use it as its emissivity in our microwave emissivity database over different land cover types. Furthermore, snow cover can heavily impact the change in land cover emissivity, especially in winter.

The selectivity of noise and coupling for coherence biresonance and array-enhanced coherence biresonance in coupled neural systems

The selectivity of noise and coupling for coherence biresonance (CBR) and array-enhanced coherence biresonance (AECBR) in coupled neural systems has been investigated. It is shown that, depending on the coupling strength and noise intensity, various coherence behaviors and phenomena are exhibited, including CBR, coherence resonance without tuning, AECBR and undamped signal transmission. There exist optimal coupling and noise regions for the occurrence of CBR and AECBR in the transmission of noise-induced oscillations (NIOs).

[Efficacy of ablendazole emulsion in treatment of 212 patients with cystic echinococcosis]

OBJECTIVE

To verify the efficacy of abendazole emulsion, a new formulation of abendazole, in treatment of human cystic echinococcosis.

METHODS

212 patients with liver cystic echinococcosis were treated orally with albendazole emulsion at a daily dose of 10 mg/kg or 12.5 mg/kg for 3 to 12 months or over one year. The therapeutic efficacy was mainly evaluated by image feature examined with B ultrasound examination, a short-term efficacy at the completion of treatment and a long-term efficacy followed-up for 1-4 years.

RESULTS

In 212 patients treated with albendazole emulsion at a daily dose of 10 mg/kg and 12.5 mg/kg, the average cure rate, improved rate and the rate of no avail were 74.5%, 99.1% and 0.9% respectively after termination of the treatment, and the average long-term rates were 83.1%, 89.3% and 0.6% respectively. Recurrence occurred in 18 patients(10.2%). The results indicated that the best efficacy was seen in patients treated with albendazole 12.5 mg/kg daily for 9 months. Better response was also found when the recurrent patients were re-treated with albendazole.

CONCLUSION

The efficacy of albendazole emulsion on patients with liver cystic echinococcosis is much better than that of albendazole tablet or capsule and mebendazole. Meanwhile, the efficacy of albendazole emulsion is stable with less adverse effects. The results suggest that albendazole emulsion could be the drug of choice for treatment of cystic hydatid disease.

[Preventive and therapeutic effects of hirudo on incipient acute tubular necrosis in rats]

Male Sprague-Dawley rats, weighing 180-250 g and depleted with water for 16 h, were injected with glycerol (im) to induce acute tubular necrosis, and then divided into groups given blood-activating and stasis-removing drug, Hirudo solution (GH) tap water (GW), verapamil (GV) and none (GSDW) in incipient stage separately. It was observed that levels of BUN increased at 24th and 48th h after administration of glycerol and levels of Bcr increased at 3rd, 24th and 48th h after injecting glycerol in GH were significantly lower than those increased in GW and GSDW (P less than 0.05-P less than 0.001), but roughly similar to those in GV (P greater than 0.05-P greater than 0.5). Renal histopathological damage under light microscope and electron-microscope in GH at 3rd and 24th h after administration of glycerol were also less severe than those in GW and GSDW. The results suggested that Hirudo could exert a preventive and therapeutic effects on incipient acute tubular necrosis induced by glycerol in rats.