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1.
BMC Plant Biol ; 24(1): 122, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373883

RESUMO

Prohexadione-Calcium (Pro-Ca) plays key roles in improving fruit quality and yield by regulating various aspects of plant growth. However, the effects of how Pro-Ca regulates the regulation of sugar and acid balance and its impact on the production of volatile aroma substances during fruit growth and development are poorly understood. In this study, the Pro-Ca solutions developed at concentrations of 200, 400, 600 and 800 mg·L-1 were sprayed on the entire "Chardonnay" grape tree 22, 42, 62 and 82 days after initial flowering. The values of endogenous hormones, sugar and acid content, enzyme activities and flavor content were then measured in grapes 45, 65, 85 and 105 days (ripeness stage) after the initial flowering. The results showed that Pro-Ca had significant effects on fruits during development, including reducing ABA content, increasing ZT, GA3 and IAA levels, promoting fruit ripening and enhancing enzymes, which are involved in sugar and acid synthesis. Consequently, these effects led to an increase in sugar and acid content in the berries. Particularly during the ripening phase, the application of 600 mg L-1 Pro-Ca resulted in an increase in soluble sugar content of 11.28% and a significant increase in citric acid and malic acid content of 97.80% and 68.86%, respectively. Additionally, Pro-Ca treatment enhanced both the variety and quantity of aroma compounds present in the berries, with the 600 mg·L-1 Pro-Ca treatment showcasing the most favorable impact on volatile aroma compounds in 'Chardonnay' grapes. The levels of aldehydes, esters, alcohols, phenols, acids, ketones, and terpenes were significantly higher under the 600 mg·L-1 Pro-Ca treatment compared to those of control with 51.46 - 423.85% increase. In conclusion, Pro-Ca can regulate the content of endogenous hormones and the activities of enzymes related to sugar and acid metabolism in fruit, thereby increasing the content of soluble sugar and organic acid in fruit and the diversity and concentration of fruit aroma substances. Among them, foliar spraying 600 mg · L-1 Pro-Ca has the best effect. In the future, we need to further understand the molecular mechanism of Pro-Ca in grape fruit to lay a solid foundation for quality improvement breeding.


Assuntos
Vitis , Vitis/metabolismo , Frutas , Cálcio/metabolismo , Açúcares/metabolismo , Melhoramento Vegetal , Carboidratos , Hormônios/metabolismo , Hormônios/farmacologia
2.
Opt Express ; 32(2): 2766-2773, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297797

RESUMO

In this study, a dual-interrogation (DI) method was used to suppress the light shift in the Rb 778 nm 5S1/2→5D5/2 two-photon transition optical frequency standard (2hν-OFS). The approach used an auxiliary system to calibrate the light shift of the primary system in real time to mitigate the absolute light shift and suppress the sensitivity of the system to the light power. Results show that after using the DI method, the absolute light shift and light-power sensitivity of the system were reduced by a factor of 10. The proposed method will improve the accuracy of the Rb 778 nm 2hν-OFS and increase the mid- and long-term stability. The method can also be applied to other vapor-cell atomic frequency standards that experience light shifts.

3.
Gastrointest Endosc ; 98(6): 893-900, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37423534

RESUMO

BACKGROUND AND AIMS: Studies on the effect of antireflux mucosectomy (ARMS) on laryngopharyngeal reflux disease (LPRD) are lacking. We conducted a multicenter retrospective study to explore the clinical efficacy of ARMS on LPRD. METHODS: We retrospectively analyzed the data of patients diagnosed with LPRD by oropharyngeal 24-hour Dx-pH monitoring who underwent ARMS. The effects of ARMS on LPRD were evaluated by comparing the 36-Item Short-Form Survey (SF-36), reflux symptom index (RSI), and 24-hour Dx-pH monitoring scores before and 1 year after surgery. Patients were divided into groups according to gastroesophageal flap valve (GEFV) grade to explore the effect of GEFV on prognosis. RESULTS: One hundred eighty-three patients were included in the study. The oropharyngeal pH monitoring results showed that the effective rate of ARMS was 72.1% (132/183). After surgery, the SF-36 score was higher (P = .000), RSI score was lower (P = .000), and the symptoms of constant throat clearing; difficulty swallowing food, liquids, and pills; coughing after eating or after lying down; troublesome or annoying cough; and breathing difficulties or choking episodes were significantly improved (P < .05). Upright reflux was dominant in GEFV grade I to III patients, and the SF-36, RSI, and upright Ryan index scores were significantly improved after surgery (P < .05). In GEFV grade IV patients, regurgitation was dominant in the supine position, and the above evaluation indexes were worse after surgery (P < .05). CONCLUSIONS: ARMS is effective for LPRD. The GEFV grade can predict the prognosis of surgery. ARMS is effective in GEFV grade I to III patients, but the effect is not exact in GEFV grade IV patients and may even be aggravated.


Assuntos
Refluxo Laringofaríngeo , Humanos , Refluxo Laringofaríngeo/etiologia , Estudos Retrospectivos , Estudos de Coortes , Endoscopia , Resultado do Tratamento
4.
Future Oncol ; 18(15): 1829-1838, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35179075

RESUMO

Aim: Older adult patients with nonmetastatic nasopharyngeal carcinoma (NPC) have poor outcomes relative to younger patients. The authors' group established a nomogram to predict the overall survival of older adults with NPC and inform patient management. Methods: Cases with NPC (n = 782) were enrolled in this study; clinical data in the Surveillance, Epidemiology, and End Results database from 2010 to 2015 served as the training cohort (n = 657), and patients from Jiangxi Cancer Hospital (n = 125) served as the external validation cohort. Results: Training and external validation cohort C-index, receiver operator characteristics curves and calibration curves showed that our nomogram has great predictive ability. Conclusions: Compared with tumor-node-metastasis staging, this nomogram can help clinicians better predict the prognosis of older adults with nonmetastatic NPC.


It is well known that more than 80% of newly diagnosed NPC patients are nonmetastatic. Older adult patients with nonmetastatic nasopharyngeal carcinoma have a poor chance of survival relative to younger patients. With the world's aging population, the treatment of older adults with nonmetastatic NPC has attracted more attention from clinicians. The use of the American Joint Committee on Cancer staging system alone has significant shortcomings in predicting survival outcomes. Therefore, the authors developed a predictive tool by combining more prognostic factors with a specific multivariable statistical model, including age, tumor stage, node stage and treatment type, which is helpful for clinicians to more accurately evaluate the prognosis of patients.


Assuntos
Neoplasias Nasofaríngeas , Nomogramas , Idoso , Humanos , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/terapia , Estadiamento de Neoplasias , Prognóstico , Programa de SEER
5.
J Integr Neurosci ; 20(2): 341-347, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34258932

RESUMO

A growing number of studies have demonstrated the role of quantitative electroencephalography in assessing brain function in neuro-intensive care units. Still, few studies have examined patients with large hemisphere infarction. Thirty patients with large hemisphere infarction were included in this preliminary study, and the patients were divided into the death group (twelve patients) and survival group (eighteen patients). Electroencephalography monitored the patients, and a computerized tomography inspection was performed. The quantitative electroencephalography of the alpha-beta/delta-theta ratio change index was calculated and used to predict the prognosis of early large hemisphere infarction patients. The relationship between three months modified Rankin Scale, and alpha-beta/delta-theta ratio change index was analyzed. The death group had negative changes for alpha-beta/delta-theta ratio change index (-0.0140 ± 0.0193), while there was an opposite trend in the survival group, the median is 0.004 (-0.0067, 0.0137). The death group's brain function decreased more severely and rapidly than the survival group (P = 0.004). The highest diagnostic value (AUC value 0.815, P < 0.001) was observed when the alpha-beta/delta-theta ratio change index dropped and exceeded -0.008. The area under the GCS curve was 0.674, but its predictive ability was low (P = 0.094). The correlation analysis result showed that the 3-month modified Rankin Scale was negatively correlated with the alpha-beta/delta-theta ratio change index (r = -0.489, P = 0.006). The alpha-beta/delta-theta ratio change index is considered an indicator for predicting the prognosis of large hemisphere infarction. Therefore, the alpha-beta/delta-theta ratio change index may be a reliable quantitative EEG parameter that predicts the early prognosis of patients with acute large hemispheric infarction.


Assuntos
Ondas Encefálicas/fisiologia , Infarto Cerebral/diagnóstico , Infarto Cerebral/fisiopatologia , Eletroencefalografia/normas , Idoso , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Índice de Gravidade de Doença
6.
Bull Environ Contam Toxicol ; 107(3): 449-458, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33839798

RESUMO

Methylmercury presents potent neurotoxicity to humans. Fish consumption is the leading source of human exposure to methylmercury worldwide. However, the exposure source in Tibet remains poorly understood because of the scarcity of observational data on most Tibetan foods, although high mercury levels were recently detected in some traditional Tibetan medicines. Here, the results of field investigations show that the joint consumption of traditional Tibetan medicines (TTMs), fish, and rice constitutes a primary exposure pathway to methylmercury in Tibetans and that the probable daily intake of methylmercury is close to that for many coastal regions. People who are young and high-income may have higher methylmercury exposure levels mainly because of economic development and cultural exchanges among regions. Our analysis indicates that a large proportion of the Tibetan population are likely to face a high methylmercury exposure risk and that mercury-susceptible populations in Tibet should be attentive to consuming TTMs with fish.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Animais , Peixes , Contaminação de Alimentos/análise , Humanos , Medicina Tradicional Tibetana , Mercúrio/análise , Mercúrio/toxicidade , Compostos de Metilmercúrio/análise , Compostos de Metilmercúrio/toxicidade , Tibet
7.
J Acoust Soc Am ; 147(5): 3360, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32486772

RESUMO

In noisy environments, the acoustic wave is complicated and consists of the radiated wave, the incident wave, as well as its scattering wave. Double-layered pressure measurement is introduced to the boundary element method based near field acoustic holography to recover the free field quantities. First, the incoming and outgoing propagation waves are separated by exploring the propagation property of the two waves from their source to the field with the boundary integral equation. Subsequently, the scattering wave is filtered out by considering the boundary condition of the vibrating structure. Further, a measurement on an enclosing hologram is adopted to accurately reconstruct the distribution of normal velocity on the boundary. Two sets of the system of linear equations are built on the double-layered measurements. The Schur complement equation is then applied in conjunction with the Tikhonov regularization method to obtain an optimized reconstruction. Numerical examples are set up for two representative radiators impinged by incident waves. It is demonstrated that the free field normal velocity can be correctly reconstructed even if the signal-to-noise ratio is negative. An experiment is conducted for the cubic radiator to verify the accuracy and potential for the practical reconstruction in a noisy environment.

8.
Int J Syst Evol Microbiol ; 69(9): 2709-2716, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31310191

RESUMO

Moutai-flavour Daqu is an important starter to support growth of microorganisms in the fermented process of Moutai-flavour liquor. A novel thermophilic microorganism, designated strain FBKL4.011T, was isolated from Moutai-flavour Daqu samples collected from Guotai distillery in Renhuai, Guizhou province, south-west China. The strain could grow at 45-65 °C (optimum 45 °C). Based on polyphasic analysis, strain FBKL4.011T was affiliated to the genus Thermoflavimicrobium. It formed abundant pale-yellow aerial and substrate mycelium, bearing single endospores (7.0-10.0 µm diameter) on branched long sporophores (5.0 µm diameter). The cell-wall peptidoglycan contained meso-diaminopimelic acid; ribose, glucose and mannose were the primary whole-cell sugars. The major fatty acids were iso-C14 : 0, iso-C15 : 0, anteiso-C15 : 0 and iso-C16 : 0. The predominant menaquinone were MK-8 and MK-9. The polar phospholipids contained diphosphatidyl glycerol, phosphatidyl ethanolamine, one unidentified phospholipid and one unidentified lipid. The G+C content of the genome was 43.1 mol%. According to the 16S rRNA gene sequence analysis, strain FBKL4.011T was closely related to Thermoflavimicrobium dichotomicum JCM 9688T (95.3 % sequence similarity), and other members within the family Thermoactinomycetaceae (less than 93.0 % sequence similarity). The DNA-DNA hybridisation data showed low relatedness between strain FBKL4.011T and T. dichotomicum JCM 9688T, Laceyella sacchari KCTC 9790T, Laceyella tengchongensis YIM 10002T, Laceyella sediminis RHA1T(36.7±1.1 %, 30.0±1.2 %, 21.3±2.1 % % and 37.6±0.9 %, respectively). Based on data from the polyphasic analysis, strain FBKL4.011T is considered to represent a novel species of the genus Thermoflavimicrobium, for which the name Thermoflavimicrobium daqui sp. nov. is proposed. The type strain is FBKL4.011T(=KCTC 43036T=CICC 24504T).


Assuntos
Bebidas Alcoólicas/microbiologia , Bacillales/classificação , Filogenia , Bacillales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Esporos Bacterianos , Vitamina K 2/química
9.
Eur Radiol ; 29(6): 3036-3043, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30506217

RESUMO

OBJECTIVE: To investigate the value of prospectively ECG-triggered coronary CT angiography (CCTA) for lean patients with body mass index (BMI) ≤ 23 kg/m2 using 70 kVp and high-level volume-based adaptive statistical iterative reconstruction (ASiR-V) algorithm on a 16-cm wide-detector CT system for reducing both radiation and contrast doses in comparison with the conventional 100-kVp protocol. MATERIALS AND METHODS: Thirty patients (group A) were prospectively enrolled to undergo 70-kVp CCTA on a 16-cm wide-detector CT scanner with noise index (NI) of 36 HU and at weight-dependent contrast dose rate of 16 mg I/kg/s for 9-s injection. Images were reconstructed with 80% ASiR-V. Radiation dose, contrast dose, and image quality were statistically compared with 30 patients (group B) in database with matching BMI who underwent conventional 100-kVp CCTA with NI of 25 HU, and at 25 mg I/kg/s rate for 10-s injection and reconstructed with 60% ASiR-V. RESULTS: There was no significant difference in patient demographics between the two groups (all p > 0.05). The two groups also had similar mean CT values and contrast-noise ratio (CNR) and subjective image quality (all p > 0.05). However, group A with 70 kVp reduced the effective dose by 75.3% compared with group B (0.43 ± 0.20 mSv vs. 1.74 ± 1.01 mSv, p < 0.001), and required 42.4% less contrast dose than group B (22.46 ± 2.94 ml vs. 38.99 ± 5.10 ml, p < 0.001). CONCLUSIONS: Prospectively ECG-triggered CCTA using 70 kVp and high-level ASiR-V on a 16-cm wide-detector CT system provides diagnostic images with substantial reduction in both radiation and contrast doses for patients with BMI ≤ 23 kg/m2 compared to the conventional 100-kVp protocol. KEY POINTS: • 70-kVp CCTA produces excellent images at sub-millisievert radiation. • 70-kVp CCTA reduces both radiation and contrast doses over conventional protocol. • Achieving low-dose CCTA with combined low kVp and high-level ASIR-V.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Adulto , Idoso , Algoritmos , Índice de Massa Corporal , Protocolos Clínicos , Meios de Contraste/administração & dosagem , Eletrocardiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Cintilografia , Magreza
10.
J Comput Assist Tomogr ; 42(6): 906-911, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30119063

RESUMO

OBJECTIVE: The aim of this study was to investigate radiation dose and image quality of coronary computed tomography (CT) angiography (CCTA) for patients with high heart rate variability (HRv) using 16-cm wide-detector CT scanner. METHODS: One hundred sixty-six patients with uncontrolled heart rate underwent CCTA on a 16-cm wide-detector CT system and were divided into 2 groups based on their HRv for analysis: group A (n = 95, HRv ≤10 beats/min [bpm]) and group B (n = 71, HRv >10 bpm). Images in both groups were reconstructed with motion correction algorithm. Subjective and objective image qualities were analyzed. RESULTS: There were no significant differences in age, body mass index, and heart rate (68.1 ± 11.4 vs 67.6 ± 12.3 bpm) between the 2 groups (P > 0.05). However, group B had significantly higher HRv than group A (33.5 ± 24.4 vs 7.8 ± 1.2 bpm, P < 0.001). All images were acceptable for clinical diagnosis. Compared with group A, image quality scores in group B decreased slightly (4.1 ± 0.5 vs 4.0 ± 0.6). However, the difference was not statistically significant. The mean effective doses were both relatively low at 2.2 ± 1.1 mSv in group A and 2.6 ± 1.4 mSv in group B. CONCLUSIONS: Single-heartbeat free-breathing CCTA can be performed for patients with high HRv using 16-cm wide-detector CT scanner to achieve diagnostic image quality with low radiation dose.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Frequência Cardíaca/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Angiografia por Tomografia Computadorizada/instrumentação , Angiografia Coronária/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Razão Sinal-Ruído
11.
BMC Cancer ; 17(1): 217, 2017 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-28347273

RESUMO

BACKGROUND: This study aimed to analyze the pattern of lymphogenous and hematogenous metastases in patients with stage IVb thymic carcinomas and identify prognostic factors for their survivals. METHODS: Between September 1978 and October 2014, 68 patients with pathologically confirmed stage IVb thymic carcinomas were treated at Fudan University Shanghai Cancer Center. Forty-three patients had lymph node involvement without distant metastases, and the remaining 25 patients had hematogenous metastases. Clinical-pathological characteristics, including age, sex, histologic subtype, tumor size, metastasis, treatment modalities, such as surgical resection, radiotherapy, and chemotherapy, and clinical outcomes, such as overall survival (OS) and progression free survival (PFS), were analyzed. RESULTS: The median follow-up time was 22 months (range, 1-126 months). The median OS of all patients with stage IVb thymic carcinomas was 30 months, and the 5-year overall survival rate was 25.1%. The median PFS was 11 months, and the 5-year PFS was 17.9%. Stage IVb patients with lymph node involvement had a better survival than those with distant metastasis (40 vs. 20 months, p = 0.002). Patients with myasthenia gravis had a worse prognosis (p = 0.033). Multivariate analysis identified metastatic status as an independent prognostic factor for OS in patients with stage IVb thymic carcinomas. CONCLUSIONS: Patients with lymph node involvement had a better survival than those with distant metastases. Much work remains to investigate the prognosis of patients with stage IVb thymic carcinomas and to explore different treatment strategies for patients with lymph node involvement and distant metastases.


Assuntos
Miastenia Gravis/patologia , Prognóstico , Timoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , Excisão de Linfonodo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/tratamento farmacológico , Miastenia Gravis/radioterapia , Miastenia Gravis/cirurgia , Estadiamento de Neoplasias , Timoma/tratamento farmacológico , Timoma/radioterapia , Timoma/cirurgia
12.
Indian J Microbiol ; 56(3): 353-60, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27407300

RESUMO

This paper demonstrated a biocementation technology for chromium slag by strain GM-1, a calcifying ureolytic bacterium identified as Microbacterium, based on microbially induced calcium carbonate. The characterization of Microbacterium sp. GM-1 was assessed to know the growth curve in different concentrations of Cr(VI). Microbacterium sp. GM-1 was tolerant to a concentration of 120 mg/L Cr(VI). Chromium waste forms were prepared using chromium, sand, soil and bacterial culture. There we had three quality ratios (8:2:1; 8:1:1; 8:2:0.5) of material (chromium, sand and soil, respectively). Bacterial and control chromium waste forms were analyzed by thermal gravimetric analyzer. All bacterial forms (8:2:1; 8:1:1; 8:2:0.5 J) showed sharp weight loss near the decomposition temperature of calcium carbonate between 600 and 700 °C. It indicated that the efficient bacterial strain GM-1 had induced calcium carbonate precipitate during bioremediation process. A five step Cr(VI) sequential extraction was performed to evaluate its distribution pattern in chromium waste forms. The percentage of Cr(VI) was found to significantly be decreased in the exchangeable fraction of chromium waste forms and subsequently, that was markedly increased in carbonated fraction after biocementation by GM-1. Further, compressive strength test and leaching test were carried out. The results showed that chromium waste forms after biocementation had higher compressive strength and lower leaching toxicity. Additionally, the samples made of 8:1:1 (m/m/m) chromium + sand + soil were found to develop the highest compressive strength and stand the lowest concentration of Cr(VI) released into the environment.

13.
Ultrastruct Pathol ; 38(3): 211-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24625130

RESUMO

To investigate the effects of X-ray irradiation on the proliferation and apoptosis of MCF-7 breast cancer cells; MCF-7 breast cancer cells were irradiated with X-ray. After irradiation, morphological changes and growth inhibition rate of the irradiated cells were observed under an inverted microscope. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to assess the proliferation of the irradiated MCF-7 cells. Transmission electron microscope was used to observe the morphology and ultrastructure of the irradiated MCF-7 cells. Western blotting was used to analyze the expression level of apoptosis-related protein caspase-3. Our results showed, at 48 h after the irradiation (0 Gy and 8 Gy), cells oval in shape, cell shrinkage or swelling and partial formation of debris under inverted microscope; as well as cytoplasmic vacuolization or inspissation, increased electron density of cytoplasm, structural damage of organelles, blurred mitochondrial cristae and chromatin margination under transmission electron microscopy; the survival rate of MCF-7 cells in X-ray group was 17.3% lower than that in control group (0 Gy) (p < 0.001); while caspase-3 expression increased evidently in X-ray group compared with control group (0 Gy) (p < 0.05). In conclusion, X-ray irradiation can inhibit the proliferation of MCF-7 cells and induce apoptosis through increasing caspase-3 expression.


Assuntos
Apoptose/efeitos da radiação , Neoplasias da Mama/ultraestrutura , Proliferação de Células/efeitos da radiação , Raios X , Neoplasias da Mama/metabolismo , Caspase 3/metabolismo , Forma Celular/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Feminino , Humanos , Células MCF-7 , Microscopia Eletrônica de Transmissão , Fatores de Tempo
14.
Pest Manag Sci ; 80(3): 935-952, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37794312

RESUMO

Many species of the Tephritidae family are invasive and cause huge damage to agriculture and horticulture, owing to their reproductive characteristics. In this review, we have summarized the existing studies on the reproductive behavior of Tephritidae, particularly those regarding the genes and external factors that are associated with courtship, mating, and oviposition. Furthermore, we outline the issues that still need to be addressed in fruit fly reproduction research. The review highlights the implications for understanding the reproductive behavior of fruit flies and discusses methods for their integrated management and biological control. © 2023 Society of Chemical Industry.


Assuntos
Oviposição , Tephritidae , Animais , Feminino , Corte , Comportamento Sexual Animal , Reprodução , Drosophila
15.
Sci Total Environ ; 912: 168778, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38008313

RESUMO

Drought is the driver for ecosystem production in semi-arid areas. However, the response mechanism of ecosystem productivity to drought remains largely unknown. In particular, it is still unclear whether drought limits the production via photosynthetic capacity or phenological process. Herein, we assess the effects of maximum seasonal photosynthesis, growing season length, and climate on the annual gross primary productivity (GPP) in vegetation areas of the Loess Plateau using multi-source remote sensing and climate data from 2001 to 2021. We found that maximum seasonal photosynthesis rather than growing season length dominates annual GPP, with above 90 % of the study area showing significant and positive correlation. GPP and maximum seasonal photosynthesis were positively correlated with self-calibrating Palmer Drought Severity Index (scPDSI), standardized precipitation and evapotranspiration index (SPEI) in >95 % of the study area. Structural equation model demonstrated that both drought indices contributed to the annual GPP by promoting the maximum seasonal photosynthesis. Total annual precipitation had a positive and significant effect on two drought indices, whereas the effects of temperature and radiation were not significant. Evidence from wood formation data also confirmed that low precipitation inhibited long-term carbon sequestration by decreasing the maximum growth rate in forests. Our findings suggest that drought limits ecosystem carbon sequestration by inhibiting vegetation photosynthetic capacity rather than phenology, providing a support for assessing the future dynamics of the terrestrial carbon cycle and guiding landscape management in semi-arid ecosystems.


Assuntos
Sequestro de Carbono , Ecossistema , Secas , Florestas , Estações do Ano , Fotossíntese , Mudança Climática
16.
Sci Total Environ ; 924: 171628, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38467256

RESUMO

Mass movements, driven by various non-linearly correlated factors, exhibit high randomness, posing vast difficulties for field observations and subsequent investigations into the underlying mechanisms. In this study 157 mass movement incidents (including collapses, slump and spalling) and their primary influencing factors were surveyed in a small catchment of the hilly and gully Loess Plateau, China, through intensive field investigations and remote sensing techniques. The spatial pattern of mass movement and its relation with the influencing factors were assessed, while the relative impact of different factors was studied using the canonical correlation analysis. Results showed that 1) Mass movements predominantly occurred on gully slopes steeper than 70°. Collapses were the main type of mass movement, accounting for 87.9 % of the number of samples. 2) With regard to the impact of individual factors, rainstorms (rainfall intensity >50 mm day-1) significantly enhanced the occurrence frequency, erosion area and erosion volume of mass movement. The occurrence frequency and erosion area / volume were highest at a soil dry bulk density of 1.34 g cm-3 and 1.54 g cm-3, respectively. Mass movement occurred most frequently on unvegetated or unrooted gully slopes, where the resisting effect of vegetation on mass movement was absent. Gully slopes with smooth rather than rugged profiles were also found to be typical areas of mass movement. The occurrence frequency of mass movement decreased with the elevated topographic wetness index (TWI) and distance to slope top and increased with the distance to channels. 3) For the relative impact of different factors, rainfall and shear strength were key factors facilitating and resisting the onset of mass movement, respectively, while topography exerted the greatest influence on the erosion area and volume. This study revealed the relative influence of different factors on occurrence and scale of mass movement, providing a useful reference for modelling and control of the problem.

17.
Front Microbiol ; 15: 1362089, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756732

RESUMO

Entomopathogenic fungi (EPF) are economical and environmentally friendly, forming an essential part of integrated pest management strategies. We screened six strains of Beauveria bassiana (B1-B6) (Hypocreales: Cordycipitaceae), of which B4 was the most virulent to Bactrocera dorsalis (Hendel) (Diptera: Tephritidae). We further assessed the biological characteristics of strain B4 and the environmental factors influencing its ability to infect B. dorsalis. We also evaluated the effects of B4 on two of the natural predators of B. dorsalis. We found that strain B4 was the most virulent to 3rd instar larvae, pupae, and adult B. dorsalis, causing mortality rates of 52.67, 61.33, and 90.67%, respectively. B4 was not toxic to B. dorsalis eggs. The optimum B4 effects on B. dorsalis were achieved at a relative humidity of 91-100% and a temperature of 25°C. Among the six insecticides commonly used for B. dorsalis control, 1.8% abamectin emulsifiable concentrate had the strongest inhibitory effect on B4 strain germination. B4 spraying affected both natural enemies (Amblyseius cucumeris and Anastatus japonicus), reducing the number of A. cucumeris and killing A. japonicus adults. We found a valuable strain of EPF (B4) that is virulent against many life stages of B. dorsalis and has great potential for the biological control of B. dorsalis. We also provide an important theoretical and practical base for developing a potential fungicide to control B. dorsalis.

18.
Nat Commun ; 15(1): 4242, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762562

RESUMO

P-type Fe3CoSb12-based skutterudite thin films are successfully fabricated, exhibiting high thermoelectric performance, stability, and flexibility at medium-to-high temperatures, based on preparing custom target materials and employing advanced pulsed laser deposition techniques to address the bonding challenge between the thin films and high-temperature flexible polyimide substrates. Through the optimization of fabrication processing and nominal doping concentration of Ce, the thin films show a power factor of >100 µW m-1 K-2 and a ZT close to 0.6 at 653 K. After >2000 bending cycle tests at a radius of 4 mm, only a 6 % change in resistivity can be observed. Additionally, the assembled p-type Fe3CoSb12-based flexible device exhibits a power density of 135.7 µW cm-2 under a temperature difference of 100 K with the hot side at 623 K. This work fills a gap in the realization of flexible thermoelectric devices in the medium-to-high-temperature range and holds significant practical application value.

19.
Chemosphere ; 313: 137438, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36464020

RESUMO

Arsenic (As) is a toxic pollutant in the atmosphere. The atmospheric As concentration is high over the East Asian continent. At present, there is less research on the long-term trend of atmospheric arsenic pollution, which is not conducive to understanding its behavior. Total suspended particulate matter (TSP) samples were collected in Qingdao in autumn and winter from 2016 to 2020 to analyze total arsenic (TAs), As(V) and As(III). The interannual variation patterns, influencing factors and health risks of arsenic concentrations in aerosols were discussed. The results showed that As(V) is the dominant species of arsenic in aerosols. The average concentration of TAs gradually decreased and the proportion of As(III) increased during autumn and winter from 2016 to 2020. The levels of TAs, As(V) and As(III) in aerosols increased during the heating period and on polluted days. Negative correlation between TAs/TSP and TSP indicated that higher concentrations of TSP in the atmosphere would reduce the content of TAs in particulate matter. The increase of secondary aerosol particles played a dilution effect. Mobile source emissions, biomass and coal combustion were main sources of atmospheric arsenic. The distribution range of large potential sources of atmospheric arsenic decreased from 2016 to 2020, and concentrated, mainly in parts of Shandong province and its offshore areas. Local sources contributed the most to atmospheric arsenic pollution in Qingdao in autumn and winter. TAs, As(V) and As(III) posed a low non-carcinogenic risk and a negligible carcinogenic risk to adults and children. This study reveals the influence of strict air pollution control policies on the speciation and source of arsenic in aerosols.


Assuntos
Poluentes Atmosféricos , Arsênio , Criança , Humanos , Poluentes Atmosféricos/análise , Arsênio/análise , Material Particulado/análise , Estações do Ano , China , Aerossóis/análise , Monitoramento Ambiental
20.
Water Res ; 240: 120063, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37210969

RESUMO

This study reports, for the first time, the role of shoreward transport of organic matter (OM) from subsurface chlorophyll maximum (SCM) in triggering hypoxia off the Pearl River Estuary (PRE, an outstanding example of typical estuary-shelf systems) based on field measurements. Compared to frequently observed hypoxia driven by surface eutrophication and terrestrial OM during large river discharge, we demonstrate that the upslope-transported SCM played a critical role in forming offshore hypoxia during low river discharge. Together with the plume-sourced OM trapped below the surface plume front, upslope-transported OM originating from the SCM accumulated underneath the pycnocline and consumed dissolved oxygen (DO), enhancing the bottom hypoxia. The DO consumption induced by the SCM-associated OM was estimated to contribute ∼ 26% (±23%) of the DO depletion under the pycnocline. Based on coherent and consistent physical and biogeochemical evidence and reasoning, this study reveals the contribution of SCM to bottom hypoxia off the PRE, which is unreported and likely occurs in other coastal hypoxic systems.


Assuntos
Monitoramento Ambiental , Estuários , Humanos , Clorofila , Hipóxia , Oxigênio/análise , Rios
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