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1.
Transl Lung Cancer Res ; 12(6): 1256-1263, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37425401

RESUMEN

Background: In recent years, osimertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), has been recommended as a first-line treatment for EGFR-mutant advanced non-small cell lung cancer (NSCLC). A phase III study (AENEAS) to assess the efficacy and safety of aumolertinib, another third-generation EGFR-TKI, vs. gefitinib as a first-line treatment in patients with locally advanced or metastatic NSCLC harboring EGFR mutations has also achieved positive results. Despite the improvements in progression-free survival (PFS) and overall survival (OS) of third- vs. first-generation EGFR-TKIs, combined treatment strategies to postpone drug resistance and further prolong survival benefits remain to be explored. Methods: We conducted a nonrandomized phase II trial (ChiCTR2000035140) of an oral multitarget antiangiogenic TKI (anlotinib) with third-generation EGFR-TKIs (osimertinib or aumolertinib) in untreated patients with EGFR mutation and advanced NSCLC. Anlotinib and the third-generation EGFR-TKIs were orally administrated (anlotinib at a dose of 12 mg once every other day and osimertinib at 80 mg once daily or aumolertinib at 110 mg once daily). The primary end point of the study was the objective response rate (ORR). Secondary endpoints included the disease control rate (DCR), OS, PFS, and safety of the combined treatment. Results: Enrollment was ceased due to treatment-related adverse events (trAEs) after 11 of 35 planned patients were treated. Among these 11 patients, two were lost to follow-up, and the treatment of five of the remaining nine patients was discontinued due to trAEs, including stomachache, rash, hyponatremia, pulmonary embolism, and interstitial pneumonia. AEs of grade 3 or worse were observed in five patients, but no treatment-related death occurred in these patients. Conclusions: Combining anlotinib and third-generation EGFR-TKIs in untreated EGFR-mutant patients with advanced NSCLC demonstrated significantly increased toxicity, suggesting that the combined treatment strategy was an inappropriate therapeutic choice in this setting.

2.
Inorg Chem ; 62(23): 8784-8788, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37253277

RESUMEN

Herein we report the structural change and radical generation of a cadmium-based metal-organic framework (Cd-MOF) induced by external electric fields. Under a weaker single electric field, different coordination modes of Cd-L lead to 3D → 2D structural change. Under stronger superposed electric fields, Cd-MOF was excited to produce a stable free radical. This study will provide a new avenue for the controlled assembly of MOFs.

3.
J Genet Genomics ; 50(5): 330-340, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36414223

RESUMEN

Multiple primary lung cancer (MPLC) is an increasingly prevalent subtype of lung cancer. According to recent genomic studies, the different lesions of a single MPLC patient exhibit functional similarities that may reflect evolutionary convergence. We perform whole-exome sequencing for a unique cohort of MPLC patients with multiple samples from each lesion found. Using our own and other relevant public data, evolutionary tree reconstruction reveals that cancer driver gene mutations occurred at the early trunk, indicating evolutionary contingency rather than adaptive convergence. Additionally, tumors from the same MPLC patient are as genetically diverse as those from different patients, while within-tumor genetic heterogeneity is significantly lower. Furthermore, the aberrant molecular functions enriched in mutated genes for a sample show a strong overlap with other samples from the same tumor, but not with samples from other tumors or other patients. Overall, there is no evidence of adaptive convergence during the evolution of MPLC. Most importantly, the similar between-tumor diversity and between-patient diversity suggest that personalized therapies may not adequately account for the genetic diversity among different tumors in an MPLC patient. To fully exploit the strategic value of precision medicine, targeted therapies should be designed and delivered on a per-lesion basis.


Asunto(s)
Neoplasias Pulmonares , Neoplasias Primarias Múltiples , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patología , Neoplasias Primarias Múltiples/genética , Neoplasias Primarias Múltiples/patología , Neoplasias Primarias Múltiples/cirugía , Mutación
4.
J Cardiothorac Surg ; 17(1): 278, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36320014

RESUMEN

BACKGROUND: Synchronous multiple primary lung cancers associated with small non-dominant nodules are commonly encountered. However, the incidence, follow-up, and treatment of small non-dominant tumors have been but little studied. We explored the prevalence and management of small non-dominant tumors and factors associated with interval growth. METHODS: This observational, consecutive, retrospective single-center study enrolled patients diagnosed with synchronous multiple primary lung cancers and small non-dominant tumors (≤ 6 mm in diameter) who underwent resection of the dominant tumor. The incidence, follow-up, and management of small non-dominant tumors and predictors of nodule growth were analyzed. RESULTS: There were 88 patients (12% of all lung cancer patients) with pathological diagnoses of synchronous multiple primary lung cancers. A total of 131 (18%) patients were clinically diagnosed with at least one small (≤ 6 mm in diameter) multiple primary lung cancer non-dominant tumor. 94 patients with 125 small-nodule non-dominant tumors clinically diagnosed as multiple primary lung cancers were followed-up for at least 6 months. A total of 29 (29/125, 23.2%) evidenced small pulmonary nodules (≤ 6 mm in diameter) that exhibited interval growth on follow-up computed tomography (CT). On multivariate analysis, a part-solid nodule (compared to a pGGN) (OR 1.23; 95% CI 1.08-1.40) or a solid nodule (compared to a pGGN) (OR 3.50; 95% CI 1.94-6.30) predicted small nodule interval growth. CONCLUSION: We found a relatively high incidence of multiple primary lung cancers with small non-dominant tumors exhibiting interval growth on follow-up CT, suggesting that resection of non-dominant tumors at the time of dominant tumor resection, especially when the nodules are part-solid or solid, is the optimal treatment.


Asunto(s)
Neoplasias Pulmonares , Nódulos Pulmonares Múltiples , Neoplasias Primarias Múltiples , Nódulo Pulmonar Solitario , Humanos , Prevalencia , Estudios Retrospectivos , Nódulos Pulmonares Múltiples/patología , Neoplasias Pulmonares/patología , Nódulo Pulmonar Solitario/patología
5.
Molecules ; 27(21)2022 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-36364436

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal malignancies globally. Peptide-based tumor-targeted imaging is critical for ESCC imaging. In this study, we aim to identify a peptide-targeting IGF2BP2 that specifically binds to human ESCC for near-infrared imaging of esophageal cancer. Applying phage display techniques, we identified a peptide target for IGF2BP2 which was confirmed to be highly expressed in ESCC cell lines or tumor tissue and may serve as an imaging target for ESCC. We conjugated the peptide to the NIRF group, Cy5, and further evaluated the targeting efficacy of the probe at a cellular level and in animal tumor models. The Cy5 conjugated peptide (P12-Cy5) showed a high binding affinity to human ESCC cells in vitro. In vivo, optical imaging also validated the tumor-targeting ability of P12-Cy5 in KYSE-30-bearing subcutaneous ESCC tumor models. Furthermore, the results of biodistribution showed a significantly higher fluorescence intensity in tumors compared to scrambled peptide, which is consistent with in vivo observations. In summary, an IGF2BP2-targeted peptide was successfully identified. In vitro and in vivo experiments confirmed that P12-Cy5 has high affinity, specificity and tumor-targeting properties. Thus, P12-Cy5 is a prospective NIR probe for the imaging of ESCC.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Animales , Humanos , Carcinoma de Células Escamosas de Esófago/diagnóstico por imagen , Neoplasias Esofágicas/metabolismo , Distribución Tisular , Estudios Prospectivos , Línea Celular Tumoral , Péptidos/química , Proteínas de Unión al ARN/metabolismo
6.
Interact Cardiovasc Thorac Surg ; 34(5): 799-807, 2022 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-35015846

RESUMEN

OBJECTIVES: Uniportal video-assisted thoracoscopic surgery (UniVATS) is widely used as a minimally invasive thoracic operation. The goal of our study was to analyse the effect of long-term experience with the UniVATS lobectomy on the learning curve. METHODS: The learning curves were quantitatively evaluated by the unadjusted cumulative sum, and they were segmented using joinpoint linear regression analysis. The variables were compared between subgroups using trend analysis, and linear regression analysis was applied to correlate clinical characteristics at different stages of the learning curve with the duration of the operation. RESULTS: The learning curve for the UniVATS lobectomy can be divided into 3 phases of proficiency at ∼200-300 procedures, with a fourth phase as the number of procedures increases. The 1st-52nd, 52nd-156th, 156th-244th and 244th-538th procedures comprised the preliminary learning stage, preliminary proficiency stage, proficiency stage and advanced proficiency stage, respectively. Surgical outcomes and their variability between stages improved with increasing case numbers, with the most significant addition of an auxiliary operating port and conversions. In multivariable analysis, as stages progressed, influences other than surgical experience increased the operative time, with male and extensive pleural adhesions in the preliminary proficiency stage; male and incomplete pulmonary fissures in the proficiency stage; and male, extensive pleural adhesions and incomplete pulmonary fissures in the advanced proficiency stage. CONCLUSIONS: As the number of procedures increases, there may be 4 different proficiency stages in the UniVATS lobectomy learning curve. The surgeon enters the fourth stage at approximately the 244th procedure. Moreover, at stage 4, the perioperative indicators tend to stabilize, and influences other than surgical experience become more significant.


Asunto(s)
Curva de Aprendizaje , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/cirugía , Masculino , Neumonectomía/efectos adversos , Neumonectomía/métodos , Estudios Retrospectivos , Cirugía Torácica Asistida por Video/efectos adversos , Cirugía Torácica Asistida por Video/métodos
7.
Appl Microbiol Biotechnol ; 106(2): 743-754, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34982194

RESUMEN

Nitrite-dependent anaerobic methane oxidation (n-damo) acts as a crucial link between biogeochemical carbon and nitrogen cycles. Nevertheless, very few studies have characterized n-damo microorganisms in high-latitude permafrost regions. Therefore, this study investigated the vertical distribution and diversity of n-damo bacterial communities in soil from three forest types in the permafrost regions of the Daxing'an Mountains. A total of 11 and 8 operational taxonomic units (OTUs) of n-damo 16S rRNA and pmoA genes were observed, respectively. Remarkable spatial variations in n-damo bacteria community richness, diversity, and structure were observed at different soil depths. Moreover, the abundances of n-damo bacteria (16S rRNA and pmoA genes) varied between 1.55 × 104 to 1.47 × 105 and 1.31 × 103 to 3.11 × 104 copies g-1 dry soil (ds), as demonstrated by quantitative PCR analyses. 13CH4 stable isotope tracer assays indicated that the potential n-damo rates varied from 0 to 1.26 nmol g-1 day-1, with the middle layers (20-40 cm and 40-60 cm) exhibiting significantly higher values than the upper (0-20 cm) and deeper layers (80-100 cm) in all three forest types. Redundancy analyses (RDA) indicated that total organic carbon (TOC), nitrate (NO3--N), and nitrite (NO2--N) were key modulators of the distribution of n-damo bacterial communities. This study thus demonstrated the widespread occurrence of n-damo bacteria in cold and high-latitude regions of forest ecosystems and provided important insights into the global distribution of these bacteria. KEY POINTS: • This study detected n-damo bacteria in soil samples obtained from the permafrost region of three forest types in the Daxing'an Mountains. • The community composition of n-damo bacteria was mainly affected by soil depth and not forest type. • The abundances of n-damo bacteria first increased and then decreased at higher soil depths.


Asunto(s)
Nitritos , Hielos Perennes , Anaerobiosis , Bacterias/genética , Ecosistema , Metano , Oxidación-Reducción , ARN Ribosómico 16S/genética
8.
Surg Endosc ; 36(6): 3994-4003, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34494149

RESUMEN

PURPOSE: Identifying the lymphatic drainage pathway is important for accurate lymph node (LN) dissection in esophageal cancer (EC). This study aimed to assess lymphatic drainage mapping in thoracic EC using near-infrared fluorescent (NIRF) imaging with indocyanine green (ICG) and identify its feasibility for intraoperative LN drainage visualization and dissection. METHODS: From November 2019 to August 2020, esophagectomy was performed using intraoperative NIRF navigation with ICG injected into the esophageal submucosa by endoscopy. All LNs were divided into four groups according to the NIRF status and presence of metastasis: NIRF+LN+, NIRF+LN-, NIRF-LN+, and NIRF-LN-. RESULTS: Regional LNs were detected in all 84 enrolled patients with thoracic EC. A total of 2164 LNs were removed, and the mean number of dissected LNs was 25.68 ± 12.00. NIRF+ LNs were observed in all patients and distributed at 19 LN stations, which formed lymphatic drainage maps. The top five LN stations of NIRF+ probability in upper thoracic EC were No. 7, 106ecR, 107, 1, and 106recL; in middle thoracic EC, they were No. 107, 7, 110, 1, and 105; and in lower thoracic EC, they were No. 107, 7, 110, 106recR, and 1. There were no cases of ICG-related adverse events or chylothorax. The 30-day mortality rate was 0%. Major complications included anastomotic fistula (7.14%), pneumonia (4.76%), pleural effusion (13.10%), atelectasis (3.75%), hoarseness (8.33%), and arrhythmia (4.76%). CONCLUSION: Regional LN mapping of thoracic EC was performed using ICG/NIRF imaging, which showed different preferred LN drainage stations in various anatomical locations of the thoracic esophagus. ICG/NIRF imaging is feasible for intraoperative LN drainage visualization and dissection. CLINICAL TRIAL REGISTRATION: The clinical trial registration number is NCT04173676 ( http://www. CLINICALTRIALS: gov/ ).


Asunto(s)
Neoplasias Esofágicas , Imagen Óptica , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Humanos , Verde de Indocianina , Escisión del Ganglio Linfático/métodos , Ganglios Linfáticos/patología , Imagen Óptica/métodos
9.
Saudi J Biol Sci ; 28(12): 7037-7045, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34867005

RESUMEN

In permafrost peatlands, the degradation of permafrost soil can raise soil temperature and alter moisture conditions, which increases the rate of loss of soil organic carbon (SOC). Here we selected three typical permafrost types that have very different active layer thicknesses but with soil originating from the same vegetation and which exist under comparable climatic conditions in the Da Xing'an mountain range: continuous permafrost, island permafrost, and island melting permafrost. To quantify the relative importance of control elements on SOC stabilization in these different permafrost types, we used correlation analysis to assess the relationship between organic carbon, physical and chemical properties and microorganisms, and explored the contribution of these factors to the accumulation of organic carbon. This study shows that the interaction between clay or silt, iron oxides and microorganisms have an important influence on the stability of organic carbon in permafrost peatlands.

10.
Chem Commun (Camb) ; 57(98): 13325-13328, 2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34816267

RESUMEN

The selective adsorption of APPT-Cd-MOF 1 for propyne, 2-butyne and phenylacetylene was confirmed by single-crystal analysis. In addition, the selective adsorption performance of Cd-MOF for C3H4/C3H6/C3H8 was investigated. The matching of the functionality and size/shape between porous materials and guest molecules clarified the specific recognition of 1 for linear alkyne molecules.

11.
J Cardiothorac Surg ; 16(1): 288, 2021 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-34627298

RESUMEN

BACKGROUND AND PURPOSE: We previously developed a new surgical method, namely, single-port inflatable mediastinoscopy simultaneous laparoscopic-assisted radical esophagectomy. The purpose of this study was to evaluate the effect of carbon dioxide inflation on respiration and circulation using this approach. METHODS: From April 2018 to October 2020, 105 patients underwent this novel surgical approach. The changes in respiratory and circulatory functions were reported when the mediastinal pressure and pneumoperitoneum pressure were 10 and 12 mmHg, respectively. Data on blood loss, operative time, and postoperative complications were also collected. RESULTS: 104 patients completed the operation successfully, except for 1 patient who was converted to thoracotomy because of intraoperative injury. During the operation, respectively, the heart rate, mean arterial pressure, central venous pressure, peak airway pressure, end-expiratory partial pressure of carbon dioxide and partial pressure of carbon dioxide increased in an admissibility range. The pH and oxygenation index decreased 1 h after inflation, but these values were all within a safe and acceptable range and restored to the baseline level after CO2 elimination. Postoperative complications included anastomotic fistula (8.6%), pleural effusion that needed to be treated (8.6%), chylothorax (0.9%), pneumonia (7.6%), arrhythmia (3.8%) and postoperative hoarseness (18.2%). There were no cases of perioperative death. CONCLUSIONS: When the inflation pressure in the mediastinum and abdomen was 10 mmHg and 12 mmHg, respectively, the inflation of carbon dioxide from single-port inflatable mediastinoscopy simultaneous laparoscopic-assisted radical esophagectomy did not cause serious changes in respiratory and circulatory function or increase perioperative complications.


Asunto(s)
Neoplasias Esofágicas , Laparoscopía , Neoplasias Esofágicas/cirugía , Esofagectomía , Humanos , Mediastinoscopía , Respiración
12.
iScience ; 24(9): 103002, 2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34505012

RESUMEN

Urbanization is a pressing challenge for earth's humans because it is changing not only natural environments but also agricultural lands. Yet, the consequences of cropland loss on pest insect populations that largely depend on these habitats remain largely unclear. We used a 17-year data set to investigate the dynamics of three moth pest species (i.e., striped stem borer, yellow stem borer, and pink stem borer) and their driving forces across the largest mega-urban region of China. Total abundance of three pest species is declined by about 80%, which was strongly associated with cropland loss during rapid urbanization. Our findings indicate that not only the increasing conversion of natural areas to human-dominated landscapes but also that of agricultural lands to urban landscapes can be critical to insect populations. It is therefore essential to monitor and understand the insect dynamics in rapidly urbanizing regions, which are currently found in many developing countries worldwide.

13.
Front Microbiol ; 12: 802213, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35003032

RESUMEN

As a buffer layer for the energy and water exchange between atmosphere and permafrost, the active layer is sensitive to climate warming. Changes in the thermal state in active layer can alter soil organic carbon (SOC) dynamics. It is critical to identify the response of soil microbial communities to warming to better predict the regional carbon cycle under the background of global warming. Here, the active layer soils collected from a wetland-forest ecotone in the continuous permafrost region of Northeastern China were incubated at 5 and 15°C for 45 days. High-throughput sequencing of the 16S rRNA gene was used to examine the response of bacterial community structure to experimental warming. A total of 4148 OTUs were identified, which followed the order 15°C > 5°C > pre-incubated. Incubation temperature, soil layer and their interaction have significant effects on bacterial alpha diversity (Chao index). Bacterial communities under different temperature were clearly distinguished. Chloroflexi, Actinobacteria, Proteobacteria, and Acidobacteria accounted for more than 80% of the community abundance at the phylum level. Warming decreased the relative abundance of Chloroflexi and Acidobacteria, while Actinobacteria and Proteobacteria exhibited increasing trend. At family level, the abundance of norank_o__norank_c__AD3 and Ktedonobacteraceae decreased significantly with the increase of temperature, while Micrococcaccac increased. In addition, the amount of SOC mineralization were positively correlated with the relative abundances of most bacterial phyla and SOC content. SOC content was positively correlated with the relative abundance of most bacterial phyla. Results indicate that the SOC content was the primary explanatory variable and driver of microbial regulation for SOC mineralization. Our results provide a new perspective for understanding the microbial mechanisms that accelerates SOC decomposition under warming conditions in the forest-wetland ecotone of permafrost region.

14.
Talanta ; 209: 120548, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31892058

RESUMEN

It is very necessary to develop real-time, highly sensitive and selective fluorescent probes for hypochlorite (ClO-) in living cells owing to hypochlorite's important role in pathological and physiological processes and its short life. Herein, a pyrene Schiff's base derivative was successfully developed for real-time (within seconds), highly sensitive detecting ClO- with a low detection limit (5.7 nM) and wide pH range (4.0-11.0) based on nucleophilic addition and subsequent hydrolysis mechanism. The probe has aggregation-induced emission properties and emits yellow fluorescence (544 nm) in PBS solution, while it exhibits blue fluorescence in other organic solvents (426 nm (THF) - 460 nm (MeOH)). The probe can be used to response ClO- in A549 cells with low cytotoxicity, a good cell membranes penetration and good biocompatibility. Cell uptake experiment indicates that probe getting into the cells is energy-dependent and is not attributed to endocytosis. Moreover, the probe is successfully used in real water sample to detect ClO- and it can be expected to be applied to ClO- participated biological and pathological functions in biological systems.


Asunto(s)
Colorantes Fluorescentes/química , Ácido Hipocloroso/análisis , Pirenos/química , Bases de Schiff/química , Células A549 , Células HeLa , Humanos , Límite de Detección , Imagen Óptica/métodos
15.
Transl Cancer Res ; 9(8): 4976-4981, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35117859

RESUMEN

Minimally invasive esophagectomy (MIE) has been developed for decades. However, conventional MIE requires transthoracic surgery, which can increase the risk of many perioperative cardiopulmonary complications. Therefore, mediastinoscopy-assisted transhiatal esophagectomy has been proposed, but the traditional surgical methods have shortcomings, such as unclear vision, especially during the dissection of mediastinal lymph nodes (LNs). A new approach for mediastinal lymphadenectomy under single-port inflatable mediastinoscopy with one left-neck incision is proposed. There are three difficulties in this procedure. (I) LNs along the left recurrent laryngeal nerve (RLN). After establishing pneumomediastinum, esophagectomy is performed over the aortic arch to the level of the lower edge of the left main bronchus, and lymphadenectomy along the left RLN is also accomplished during this process. (II) LNs along the right RLN. At the level of the lower edge of the right subclavian artery (RSA), between the trachea and the esophagus, instruments are used to access the right RLN. Lymphadenectomy of up to 2 cm can be accomplished at the upper edge of the RSA. (III) Subcarinal LNs. Between the trachea and esophagus, the left and right main bronchi are exposed along the trailing edge of the trachea down to the carina, and lymphadenectomy can be performed here. The surgical procedure described here in detail is the first mediastinal lymphadenectomy under mediastinoscopy with one single left-neck incision.

16.
Chem Commun (Camb) ; 55(99): 14980-14983, 2019 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-31777874

RESUMEN

A ratiometric fluorescent probe for hydrazine based on a coumarin chalcone framework and a levulinic acid terminal group with a low detection limit (0.1 ppb, 0.003 µM), a large ratiometric fluorescence change (I465/I575, 1265-fold enhancement) and a wide pH work range (3.0-12.0) was developed. The mechanism analysis of the isolated hydrazine product characterized by NMR, HRMS and the crystal structure indicates that the levulinic acid group is firstly removed by deprotection and then the dihydropyrazole ring is formed due to the addition and subsequent cyclization reaction in the presence of hydrazine.

17.
Artículo en Inglés | MEDLINE | ID: mdl-31434321

RESUMEN

With global warming, the large amount of greenhouse gas emissions released by permafrost degradation is important in the global carbon and nitrogen cycle. To study the feedback effect of greenhouse gases on climate change in permafrost regions, emissions of CO2, CH4, and N2O were continuously measured by using the static chamber-gas chromatograph method, in three forest soil ecosystems (Larix gmelinii, Pinus sylvestris var. mongolica, and Betula platyphylla) of the Daxing'an Mountains, northeast China, from May 2016 to April 2018. Their dynamic characteristics, as well as the key environmental affecting factors, were also analyzed. The results showed that the flux variation ranges of CO2, CH4, and N2O were 7.92 ± 1.30~650.93 ± 28.12 mg·m-2·h-1, -57.71 ± 4.65~32.51 ± 13.03 ug·m-2·h-1, and -3.87 ± 1.35~31.1 ± 2.92 ug·m-2·h-1, respectively. The three greenhouse gas fluxes showed significant seasonal variations, and differences in soil CO2 and CH4 fluxes between different forest types were significant. The calculation fluxes indicated that the permafrost soil of the Daxing'an Mountains may be a potential source of CO2 and N2O, and a sink of CH4. Each greenhouse gas was controlled using different key environmental factors. Based on the analysis of Q10 values and global warming potential, the obtained results demonstrated that greenhouse gas emissions from forest soil ecosystems in the permafrost region of the Daxing'an Mountains, northeast China, promote the global greenhouse effect.


Asunto(s)
Dióxido de Carbono/análisis , Bosques , Metano/análisis , Óxido Nitroso/análisis , Hielos Perennes/química , Suelo/química , China , Cambio Climático , Estaciones del Año
19.
J Pest Sci (2004) ; 92(2): 417-428, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30956648

RESUMEN

Rice planthoppers and associated virus diseases have become the most important pests threatening food security in China and other Asian countries, incurring costs of hundreds of millions of US dollars annually in rice losses, and in expensive, environmentally harmful, and often futile control efforts. The most economically damaging species, the brown planthopper, Nilaparvata lugens (Hemiptera: Delphacidae), cannot overwinter in temperate East Asia, and infestations there are initiated by several waves of windborne spring or summer migrants originating from tropical areas in Indochina. The interaction of these waves of migrants and synoptic weather patterns, driven by the semi-permanent western Pacific subtropical high-pressure (WPSH) system, is of critical importance in forecasting the timing and intensity of immigration events and determining the seriousness of subsequent planthopper build-up in the rice crop. We analysed a 26-year data set from a standardised light trap network in Southern China, showing that planthopper aerial transport and concentration processes are associated with the characteristics (strength and position) of the WPSH in the year concerned. Then, using N. lugens abundance in source areas and indices of WPSH intensity or related sea surface temperature anomalies, we developed a model to predict planthopper numbers immigrating into the key rice-growing area of the Lower Yangtze Valley. We also demonstrate that these WPSH-related climatic indices combined with early-season planthopper catches can be used to forecast, several months in advance, the severity of that season's N. lugens infestations (the correlation between model predictions and outcomes was 0.59), thus allowing time for effective control measures to be implemented.

20.
Inorg Chem ; 58(5): 2916-2920, 2019 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-30784270

RESUMEN

Four [Ag-Ag]2+ unit-encapsulated trimetallic cages 1-4 were synthesized from one new tripodal ligand L and silver salts in different solvent systems by a one-pot method. The formation of coordination cages occurred simultaneously with the condensation of amino groups and ketone. The remarkable structural feature of cages 1-4 is their spontaneous incorporation of [Ag-Ag]2+ cationic units. Moreover, the argentophilic interactions are modulated by the uncoordinated amino substituents. The study herein shows that modification and subtle changes of the cage structures could be realized by a one-pot synthetic method.

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