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1.
Plant Dis ; 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36724104

RESUMO

Paeoniae radix Rubra is a traditional Chinese herbal medicine, which has the effect of clearing heat and cooling blood, activating blood and removing stasis. It has become popular in the Chinese market in recent years due to its extremely high medicinal value and showy flower color. In May 2021, typical symptoms of root rot were observed in a field (35°7'12″ N, 103°58'48″ E) in Dingxi, Gansu province, China. Approximately 10% of the plants in the field had typical root rot symptoms, and the root of each affected plant is at least 5% severe. The roots of the naturally infected plants in the field discolored and decayed with black brown spots on the surface of the root bark, the root bark detached from the phloem,and some leaves were chlorosis, shrunken and smaller, and the branches were dead and underdeveloped. In the transverse section, the xylem was black diffusion and abnormal odor. Three diseased plants with typical symptoms were chosen at random and brought back to the lab. Small pieces cut from the margins of lesions were surface disinfested with 75% ethanol for 15 s, and 0.5% NaClO solution for 30 s, rinsed three times in sterile distilled water, dried on sterile filter paper, plaed onto potato dextrose agar (PDA), and incubated at 25 ± 1℃ for 7 days in the dark. The pure cultures were obtained by single-spore isolation. All isolates produced wavy on the surface, radial from the inside out, initially white or milky white to orange colonies with abundant black brown oily conidiomata pycnidia on PDA at 25 ± 1℃ after 15 days in the dark. The conidiomata pycnidia is spherical to irregularly spherical, 231.5 to 512.4 µm, initially transparent with age turning brown, with a dark brown internal conidial mass inside, and with a 13.1 to 45.4 µ m wide ostiole central. Young conidia (n=100) developed from conidiogenous cells, which were simple, tapering, hyaline, smooth, and 12.3 to 18.0 × 2.5 to 4.6 µm, 1.0 to 1.5 µm wide at apex. Mature conidia (n=100) were ellipsoid, apices tapering, subobtusely rounded, brown, and 6.5 to 11.0 × 4.1 to 7.5 µm. The morphological characteristics of the isolates were consistent with previous descriptions of the genus Coniella (Crous et al., 2014). A representation isolate CS-1 was deposited in the Institute of Plant Protection, Gansu Academy of Agricultural Sciences and used for further studies. To confirm the identity of the causal fungus, the internal transcribed spacer (ITS), 28S large subunit of nuclear ribosomal RNA (LSU) and partial translation elongation factor 1-alpha (TEF1-α) gene of the representative isolate CS-1 were amplified and sequenced using primers ITS1/ITS4 (White et al., 1990), LROR/LR7 (Chethan et al., 2017) and EF1-728F/EF1-986R (Carbone and Kohn, 1999), respectively, and deposited on GenBank with accession numbers OP824764 (ITS), OP824767 (LSU)/span>and OP903926 (TEF1-α). Blastn analysis of all sequences resulted in E-value of 0.0 (ITS and LSU) and nearly 0.0 (TEF1-α), with Query cover values of 90% to 99% identity with C. fragariae, confirming the hypothesis based on morphological features examination. To conduct a pathogenicity test, three root segments of healthy plants were wounded using sterilized needles and inoculated by pipetting 10 µL of conidial suspension (1×107 conidia/mL) onto each wound, and controls were inoculated with 10 µL sterile distilled water. These root segments were kept in a moist chamber at 25°C in the dark. The experiment was repeated three times. After 14 days, root rot symptoms were observed on all of the inoculated root segments and identical to those observed in the field, whereas control root segments did not develop symptoms. The pathogen was re-isolated from the lesions of inoculated root segments, fulfilling Koch's postulates. To the best of our knowledge, this is the first report of C. fragariae causing root rot on P. radix Rubra in China. This identification can aid in the selection of appropriate management measures for this disease.

2.
Microsyst Nanoeng ; 8: 93, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060526

RESUMO

Synchronization, as a unique phenomenon, has been extensively studied in biology, chaotic systems, nonlinear dynamics, quantum information, and other fields. Benefiting from the characteristics of frequency amplification, noise suppression, and stability improvement, synchronization has been gradually applied in sensing, communication, time keeping, and other applications. In the sensing field, synchronization provides a new strategy to improve the performance of sensors. However, the performance improvement is only effective within the synchronization range, and the narrow synchronization range has become a great challenge for the wide application of synchronization-enhanced sensing mechanism. Here, we propose a frequency automatic tracking system (FATS) to widen the synchronization range and track the periodic acceleration signals by adjusting the frequency of the readout oscillator in real time. In addition, a high-precision frequency measurement system and fast response control system based on FPGA (Field Programmable Gate Array) are built, and the tracking performance of the FATS for static and dynamic external signals is analyzed to obtain the optimal control parameters. Experimental results show that the proposed automatic tracking system is capable of static acceleration measurement, the synchronization range can be expanded to 975 Hz, and the relocking time is shortened to 93.4 ms at best. By selecting the optimal PID parameters, we achieve a faster relocking time to meet the requirements of low-frequency vibration measurements, such as seismic detection and tidal monitoring.

3.
Sensors (Basel) ; 22(5)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35271120

RESUMO

Pressure sensors have important prospects in wind pressure monitoring of transmission line towers. Optical pressure sensors are more suitable for transmission line towers due to its anti-electromagnetic interference. However, the fiber pressure sensor is not a suitable choice due to expensive and bulky. In this paper, a compact optical Fabry-Pérot (FP) pressure sensor for wind pressure measurement was developed by MEMS technology. The pressure sensor consists of a MEMS sensing chip, a vertical-cavity surface-emitting laser (Vcsel), and a photodiode (PD). The sensing chip is combined with an FP cavity and a pressure sensing diaphragm which adopts the square film and is fabricated by Silicon on Insulator (SOI) wafer. To calibrate the pressure sensor, the experimental platform which consists of a digital pressure gauge, a pressure loading machine, a digital multimeter, and a laser driver was set up. The experimental results show that the sensitivity of the diaphragm is 117.5 nm/kPa. The measurement range and sensitivity of the pressure sensor are 0-700 Pa and 115 nA/kPa, respectively. The nonlinearity, repeatability, and hysteresis of the pressure sensor are 1.48%FS, 2.23%FS, and 1.59%FS, respectively, which lead to the pressure accuracy of 3.12%FS.

4.
Transl Cancer Res ; 9(1): 30-41, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35117155

RESUMO

BACKGROUND: To investigate the correlation between quantitative pharmacokinetic parameters and clinicopathological prognostic biomarkers including estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and MiB1 (Ki-67) in patients with breast cancer, the image histogram analysis was performed on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). METHODS: The reference region model (RRM) was used to calculate the quantitative permeability parameters, including reference region volume transfer constant (Ktrans,RR ), the rate constant of tissue of interest (Kep,TOI ), and the rate constant of reference region (Kep,RR ). Histogram analysis was performed to compare these parameters between ER/PR/HER2/Ki-67 positive and negative groups. The performance of the histogram parameters Ktrans,RR , Kep,TOI and Kep,RR in differential diagnosis of immunohistochemistry results was conducted by receiver operating characteristic (ROC) curve analysis. RESULTS: All the histogram metrics of Kep,TOI significantly differed between ER/PR positive and negative groups (P<0.05). However, Ktrans,RR and Kep,RR did not significantly differ between ER/PR positive and negative groups (P>0.05). The 10th percentile, energy, entropy and variance of Ktrans,RR , and almost all the histogram parameters of Kep,TOI except for variance significantly differed between HER2 positive and negative groups (all P<0.05). The energy of Ktrans,RR significantly differed between Ki-67 positive and negative groups (P<0.05). The skewness and energy of Kep,TOI showed the highest AUC of 0.977 and 0.879 in differentiating ER/PR status. The energy of Ktrans,RR presented the highest AUC in the differentiation of HER2 and Ki-67. CONCLUSIONS: Histogram analysis on quantitative pharmacokinetic breast parameters using DCE-MRI improves the performance in differentiation of histological phenotypes of breast cancer.

5.
Int J Inj Contr Saf Promot ; 25(4): 439-442, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29792558

RESUMO

Falls are the top one type in all unintentional injuries. In this study, we aim to explore the epidemiological characteristics of falls and assess the intervention effect. Our research had interviewed 2854 rural children in southwest China. Then, we used School-Family-Individual (SFI) comprehensive education model to conduct an intervention among 1506 children and follow up them for one year. The changes in injury knowledge and incidence rate before and after intervention were compared. We found the fall injury was 37.32% (178/477) and ranked top one in the total injuries. After intervention, the children's fall-injuries-related knowledge was significantly increased by 15.29 percent (P < 0.001). While falls incidence significantly decreased after- intervention (6.24% vs. 3.93%; P < 0.001). From the results we concluded that the falls rate was high and was the prior reason of all injuries. SFI intervention model can effectively reduce the incidence of the fall injury.


Assuntos
Acidentes por Quedas/prevenção & controle , Acidentes por Quedas/estatística & dados numéricos , Educação em Saúde , Ferimentos e Lesões/epidemiologia , Adolescente , Criança , China/epidemiologia , Estudos de Coortes , Feminino , Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Incidência , Masculino , Jogos e Brinquedos/lesões , População Rural , Ferimentos e Lesões/etiologia , Ferimentos e Lesões/prevenção & controle
6.
J Plant Physiol ; 212: 115-124, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28314173

RESUMO

Root-knot nematodes (Meloidogyne spp.) cause serious threat to cucumber production. Cucumis metuliferus, a relative of cucumber, is reported to be resistant to Meloidogyne incognita, yet the underlying resistance mechanism remains unclear. In this study, the response of resistant C. metuliferus accession PI482443 following nematode infection was studied in comparison with susceptible C. sativus cv. Jinlv No.3. Roots of selected Cucumis seedings were analysed using histological and biochemical techniques. Transcriptome changes of the resistance reaction were investigated by RNA-seq. The results showed that penetration and development of the nematode in resistant plants were reduced when compared to susceptible plants. Infection of a resistant genotype with M. incognita resulted in a hypersensitive reaction. The induction of phenylalanine ammonia lyase and peroxidase activities after infection was greater in resistant than susceptible roots. Several of the most relevant genes for phenylpropanoid biosynthesis, plant hormone signal transduction, and the plant-pathogen interaction pathway that are involved in resistance to the nematode were significantly altered. The resistance in C. metuliferus PI482443 to M. incognita was associated with reduced nematode penetration, retardation of nematode development, and hypersensitive necrosis. The expression of genes resulting in the deposition of lignin, toxic compounds synthesis, cell wall reinforcement, suppression of nematode feeding and resistance protein accumulation, and activation of several transcription factors might all contribute to the resistance response to the pest. These results may lead to a better understanding of the resistance mechanism and aid in the identification of potential targets resistant to pests for cucumber improvement.


Assuntos
Cucumis/genética , Cucumis/parasitologia , Resistência à Doença/genética , Doenças das Plantas/parasitologia , Transcriptoma , Tylenchoidea/patogenicidade , Animais , Cucumis/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Genótipo , Interações Hospedeiro-Parasita/genética , Anotação de Sequência Molecular , Células Vegetais , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/enzimologia , Raízes de Plantas/parasitologia , Análise de Sequência de RNA , Transdução de Sinais , Fatores de Transcrição
7.
Iran J Parasitol ; 10(1): 122-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25904955

RESUMO

BACKGROUND: To analyze the characteristic performance of magnetic resonance spectroscopy (MRS) and susceptibility weighted imaging (SWI) in cerebral alveolar echinococcosis (CAE). METHODS: We retrospectively analyzed 10 clinical-identified CAE cases MR performance, and summarized the MRS and SWI performance of CAE. RESULTS: The 10 cases of CAE all had the history of primary HAE, among who 6 cases had single lesion (60%), while the rest 4 cases had multiple lesions (40%); and 4 cases were concomitant with lung metastases. MRI performance: T2WI lesions were coal-like low-signal shadow, with multiple small vesicles inside the lesions; MRS performance: NAA, Cho and Cr significantly reduced, an abnormally high and steep crest was found at 1.4 ppm; the phase diagram and strength diagram of SWI showed isointensity. CONCLUSION: The MRS and SWI of CAE could provide important supplemental information for the diagnosis of CAE, especially the abnormally high and steep crest at 1.4 ppm provide the reliable image basis for the diagnosis and differential diagnosis of CAE.

8.
Int J Environ Res Public Health ; 12(4): 3903-14, 2015 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-25856553

RESUMO

OBJECTIVE: To explore the effect of a school-family-individual (SFI) multi-level education intervention model on knowledge and attitudes about accidental injuries among school-aged children to improve injury prevention strategies and reduce the incidence of pediatric injuries. METHODS: The random sample of rural school-aged children were recruited by using a multistage, stratified, cluster sampling method in Zunyi, Southwest China from 2012 to 2014, and 2342 children were randomly divided into intervention and control groups. Then children answered a baseline survey to collect knowledge and attitude scores (KAS) of accidental injuries. In the intervention group, children, their parents/guardians and the school received a SFI multi-level education intervention, which included a children's injury-prevention poster at schools, an open letter about security instruction for parents/guardians and multiple-media health education (Microsoft PowerPoint lectures, videos, handbooks, etc.) to children. Children in the control group were given only handbook education. After 16 months, children answered a follow-up survey to collect data on accidental injury types and accidental injury-related KAS for comparing the intervention and control groups and baseline and follow-up data. RESULTS: The distribution of gender was not significantly different while age was different between the baseline and follow-up survey. At baseline, the mean KAS was lower for the intervention than control group (15.37 ± 3.40 and 18.35 ± 5.01; p < 0.001). At follow-up, the mean KAS was higher for the intervention than control group (21.16 ± 3.05 and 20.02 ± 3.40; p < 0.001). The increase in KAS in the intervention and control groups was significant (p < 0.001; KAS: 5.79 vs. 1.67) and suggested that children's injury-related KAS improved in the intervention group. Moreover, the KAS between the groups differed for most subtypes of incidental injuries (based on International Classification of Diseases 10, ICD-10) (p < 0.05). Before intervention, 350 children had reported their accident injury episodes, while after intervention 237 children had reported their accidental injury episodes in the follow-up survey. CONCLUSIONS: SFI multi-level education intervention could significantly increase KAS for accidental injuries, which should improve children's prevention-related knowledge and attitudes about such injuries. It should help children change their risk behaviors and reduce the incidence of accidental injuries. Our results highlight a new intervention model of injury prevention among school-aged children.


Assuntos
Prevenção de Acidentes/métodos , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Ferimentos e Lesões/psicologia , Adolescente , Criança , China , Feminino , Humanos , Masculino , Modelos Teóricos , Distribuição Aleatória , População Rural
9.
PLoS One ; 9(7): e102099, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25010712

RESUMO

OBJECTIVE: We aimed to investigate the patterns and risk factors of nonfatal injuries among rural mountain-area children in southwest China. METHODS: A stratified sampling method was used to recruit rural children aged 8 to 17 years (mainly 9-14 years) from 7 schools. Self-reported injuries during the past 12 months and relevant concerns were collected from June to December 2012 by using a structured questionnaire in a class interview. RESULTS: The mean age of the 2,854 children was 12.2 ± 1.5 years. The probability of annual injury was 16.7% (95% confidence interval [95% CI] 15.3-18.1%), with slightly higher injury risk for boys than girls (17.7% vs. 16.0%; P>0.05). The top 3 causes of injuries were falls (37.3%), animal-related incidents (20.6%), and burns (14.9%). The main injury risk factors included being involved in a violent episode (odds ratio [OR] 1.34, 95% CI 1.08-1.66, P = 0.007), maltreatment by parents or guardians (1.42, 1.17-1.72, P<0.001), and being from a single-child family (1.30, 1.10-1.66, P = 0.039). Older age was a protective factor (0.81, 0.76-0.87, P<0.001). CONCLUSIONS: The incidence of nonfatal injury among rural children was high, and falls were the leading cause. Younger children and boys from poor-care and poor-living environments were at increased risk of injury, which requires urgent attention. Injury prevention programs targeting these issues are needed in this mountain area and similar rural regions of China.


Assuntos
Ecossistema , Inquéritos Epidemiológicos , População Rural/estatística & dados numéricos , Instituições Acadêmicas/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Acidentes/estatística & dados numéricos , Adolescente , Criança , China/epidemiologia , Família , Feminino , Humanos , Incidência , Masculino , Fatores de Risco
10.
Neotrop. entomol ; 39(6): 967-976, nov.-dic. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-572479

RESUMO

The genetic diversity and genetic structure of three Chinese silkworm species Bombyx mori L., Antheraea pernyi Guérin-Meneville and Samia cynthia ricini Donovan were comparatively assessed based on RAPD markers. At the species level, A. pernyi and B. mori showed high levels of genetic diversity, whereas S. cynthia ricini showed low level of genetic diversity. However, at the strain level, A. pernyi had relatively highest genetic diversity and B. mori had lowest genetic diversity. Analysis of molecular variance (AMOVA) suggested that 60 percent and 72 percent of genetic variation resided within strains in A. pernyi and S. cynthia ricini, respectively, whereas only 16 percent of genetic variation occurred within strains in B. mori. In UPGMA dendrogram, individuals of A. pernyi and B. mori formed the strain-specific genetic clades, whereas those of S. cynthia ricini were distributed in a mixed way. The implications of these results for the conservation and utilization in breeding programs of three silkworm species are discussed.


Assuntos
Animais , Bombyx/classificação , Bombyx/genética , Variação Genética , China
11.
Neotrop Entomol ; 39(6): 967-76, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21271066

RESUMO

The genetic diversity and genetic structure of three Chinese silkworm species Bombyx mori L., Antheraea pernyi Guérin-Meneville and Samia cynthia ricini Donovan were comparatively assessed based on RAPD markers. At the species level, A. pernyi and B. mori showed high levels of genetic diversity, whereas S. cynthia ricini showed low level of genetic diversity. However, at the strain level, A. pernyi had relatively highest genetic diversity and B. mori had lowest genetic diversity. Analysis of molecular variance (AMOVA) suggested that 60% and 72% of genetic variation resided within strains in A. pernyi and S. cynthia ricini, respectively, whereas only 16% of genetic variation occurred within strains in B. mori. In UPGMA dendrogram, individuals of A. pernyi and B. mori formed the strain-specific genetic clades, whereas those of S. cynthia ricini were distributed in a mixed way. The implications of these results for the conservation and utilization in breeding programs of three silkworm species are discussed.


Assuntos
Bombyx/classificação , Bombyx/genética , Variação Genética , Animais , China
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